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High performance Peer to Peer Distributed Computing with Application to Obstacle Problem

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Sennheiser ew 系列无线麦克风系统用户手册说明书

Sennheiser ew 系列无线麦克风系统用户手册说明书

The ew 322 G3 consists of the same components as ew 312 G3but with a compact cardioid clip-on microphone.The ew 352 G3 consists of the same components as ew 312 G3but with a headworn cardioid microphone.FEATURESSturdy metal housing(transmitter and receiver)42 MHz bandwidth: 1,680 tunable UHF frequencies for interference-free reception20 frequency banks with up to 24 compatible frequenciesEthernet port for connecting to theWireless Systems Manager (WSM) software for control via computer High-quality true diversity receptionPilot tone squelch for eliminating RF inter- ference when transmitter is turned off Automatic frequency scan feature searches for available frequencies Enhanced AF frequency rangeIncreased range for audio sensitivity Wireless synchronization of transmitter parameter from receiverUser-friendly menu operation with more control optionsIlluminated graphic display, receiver also shows transmitter settingsAuto-Lock function avoids accidental changing of settingsHDX compander for crystal-clear sound Transmitter feature battery indicatation in 4 steps, also shown on receiver display Programmable Mute function Integrated Equalizer and Soundcheck modeContacts for recharging BA 2015 accupack directly in the transmitter Wide range of accessories adapts the system to any requirementThe ew 312 G3 is a wireless microphone set, consisting of a True Diversityreceiver, a bodyworn transmitter, a compact omni directional clip-on micropho-ne plus accessories.The bodypack transmitter features charging contacts for the optional recharge-able battery. Sync up the bodypack to the receiver wirelessly with the new wireless sync. Backlit graphic displays make them easy to read under all lighting conditions.ew 300 Setsew 312 G3 Presentation Set ew 322 G3 Presentation Set ew 352 G3 Head Setew 335/345/365 G3 Vocal SetsFEATURESew 335 G3/ew 345 G3/ew 365 G3 Vocal SetsSee above mentioned list of features plus Programmable Mute switch, easyaccessableHandheld transmitter with easy-exchangeable microphone heads from evolution series The ew 335 G3 is a wireless microphone set, consisting of a True Diversity receiver, a handheld transmitter with e 835 microphone head plus accessories. It is versatile for every style of music and presentations. A wireless link from receiver to the transmitter allows synchronization of frequencies for easy setup. Backlit graphic displays make them easy to read under all lighting conditions. The ew 345 G3 consists of the same components as ew 335 G3but with an e 845 microphone head.The ew 365 G3consists of the same components as ew 335 G3but with an e 865 microphone head.ARCHITECT’S SPECIFICATIONSew 312 G3 Presentation SetComplete plug & play wireless microphone set with clip-on microphone (condenser, omni-directional) from Sennheiser evolution series for multi-purpose application. The devices shall have metal housings for rugged use. 42 MHz bandwidth with 1,680 tunable frequencies. 20 banks with up to 24 compatible frequencies, 1 bank for individual selectable frequencies, scan function and wireless synchronization to the transmitter for easy setup. HDX compander delivers high-quality sound performance. All parameters of transmitter and receiver can be monitored and controlled via Wireless Systems Manager (WSM) software from PC. The transmitter shall have a sensitivity range of 48 dB. The receiver offers a maximum output level of +18 dBu (+6 dB gain). True Diversity and pilot tone squelch for interference-free reception. Charging contacts on transmitter for recharging BA 2015 accupack directly in the transmitter shall be available. 3-step battery + LowBattery indication on transmitter and receiver shall give reliable information on operation time.Menu operation, auto-lock function and illuminated graphic displays on transmitter and receiver for user-friendly operation.A RF Mute function on transmitter and receiver allows offline settings.An easy accessable Mute switch on the transmitter can be programmed for AF on/off, RF on/off.A suitable Remote Mute Switch option also allows push-to-talk and push-to-muteAn equalizer and soundcheck mode is inte g rated in the receiver.ew 322 G3 Presentation SetComplete plug & play wireless microphone set with clip-on microphone (electret, cardioid) from Sennheiser evolution series for multi-purpose application. Further discription see paragraph ew 312 G3.ew 352 G3 Head SetComplete plug & play wireless microphone set with headworn microphone (condenser, cardioid) for hands-free application. Further discription see paragraph ew 312 G3.ew 335 G3 Vocal SetComplete plug & play wireless microphone set with easy-exchangeable e 835 microphone head (dynamic, cardioid) from Sennheiser evolution series for multi-purpose application. Further discription see paragraph ew 312 G3.ew 345 G3 Vocal SetComplete plug & play wireless microphone set with easy-exchangeable e 845 microphone head (dynamic, supercardioid) from Sennheiser evolution series for multi-pur p ose application. Further discription see paragraph ew 312 G3.ew 365 G3 Vocal SetComplete plug & play wireless microphone set with easy-exchangeable e 865 microphone head (electret-condenser, supercardioid) from Sennheiser evolution series for multi-purpose application. Further discription see paragraph ew 312 G3.SySTEMRF frequency range ................................................516.....865 MHzTransmission/receiving frequencies ...................1,680Frequency banks ..................................................... 20 (factory presets)6 (user presets)Presets .......................................................................24 max.Switching bandwidth .............................................42 MHzCompander ...............................................................HDXSignal-to-noise ratio ..............................................> 115 dB(A)THD, total harmonic distortion ............................< 0.9 %RECEIvERAF Frequency response..........................................25…18,000 HzAntenna connectors ...............................................BNC, 50 OhmAudio outputs .......................................................... X LR: +18 dBu max6.3 mm jack: +10 dBu maxDimensions ...............................................................212 x 202 x 43 mmWeight .......................................................................980 gTRANSMITTERRF output power .....................................................10/30 mW switchableOperating time ........................................................typ. 8hInput voltage range ................................................1.8 v lineInput voltage range ................................................2.4 v lineDimensions ...............................................................82 x 64 x 24 mmWeight .......................................................................~ 160 gMICROPHONETransducer; Microphone type ...............................permanent polarizedAF sensitivity ...........................................................1.6 mv/PaFrequency response ...............................................80.....18,000 HzPick-up pattern ........................................................omni-directionalContinued on page 5EM 300Modulation ...............................................................wideband FMRF frequency range ................................................ 516 – 558, 566 – 608, 626 – 668, 734 –776, 780 – 822, 823 – 865 MHz Transmission/receiving frequencies ...................1,680, tuneable in steps of 25 kHzReceiving frequencies ............................................ 1,680 frequencies, tuneable in steps of 25 kHz20 frequency banks, each with up to 24 factory-preset channels,intermodulation-free20 frequency banks with up to 24 user programmable channelsSwitching bandwidth .............................................42 MHzNominal/peak deviation .......................................±24 kHz/±48 kHzReceiver principle ....................................................true diversitySensitivity (with HDX, peak deviation) .............< 2 μv for 52 dBA rms S/NAdjacent channel rejection ...................................typ. ≥ 75 dBIntermodulation attenuation ...............................typ. ≥ 70 dBBlocking .....................................................................≥ 75 dBSquelch ...................................................................... O ff, 5 to 25 dBμv, adjustable in steps of 2 dBPilot tone squelch ...................................................can be switched offAntenna inputs .......................................................2 BNC socketsCompander system .................................................Sennheiser HDXEQ presets (switchable, affect the line and monitor outputs):Preset 1: “Flat”Preset 2: “Low Cut” ................................................–3 dB at 180 HzPreset 3: “Low Cut/High boost” .......................... –3 dB at 180 Hz+6 dB at 10 kHzPreset 4: “High Boost” ...........................................+6 dB at 10 kHzS/N ratio (1 mv, peak deviation) ........................≥ 115 dBATHD .............................................................................≤ 0.9 %AF output voltage (at peak deviation,1 kHz AF) .................................................................. ¼” (6.3 mm) jack socket (unbalanced): +12 dBuXLR socket (balanced): +18 dBuAdjustment range of audio output level ........... 48 dB, adjustable in steps of 3 dB +6 dB gain reserveTemperature range .................................................–10 °C to +55 °CPower supply............................................................12 vPower consumption:...............................................350 mADimensions ...............................................................approx. 202 x 212 x 43 mmWeight (incl. batteries) .........................................approx. 980 gIn compliance with .................................................. C E, FCC, ETS 300422, ETS 300445MAINS UNITInput voltage............................................................100 to 240 v~, 50/60 HzPower/current consumption ................................max. 120 mAOutput voltage ........................................................12 vSecondary output current .....................................400 mATemperature range .................................................–10 °C to +40 °CIn compliance with .................................................. C E, FCC, IC, ETS 300422, ETS 300445Continued on page 6SK 300 and SKM 300Modulation ...............................................................wideband FMRF frequency range ................................................ 516 – 558, 566 – 608, 626 – 668, 734 –776, 780 – 822, 823 – 865 MHz Transmission/receiving frequencies ...................1,680, tuneable in steps of 25 kHzReceiving frequencies ............................................ 1,680 frequencies, tuneable in steps of 25 kHz20 frequency banks, each with up to 24 factory-preset channels, intermodulation-free6 frequency banks with up to 24 user programmable channelsSwitching bandwidth .............................................42 MHzNominal/peak deviation .......................................±24 kHz/±48 kHzFrequency stability .................................................≤ ±15 ppmRF output power at 50 O......................................typ. 10/30 mW, switchablePilot tone squelch ...................................................can be switched offAF characteristicsCompander system .................................................Sennheiser HDXAF frequency responseSK ................................................................................ m icrophone: 80 –18,000 Hzline: 25 –18,000 HzSKM ............................................................................80 –18,000 HzS/N ratio (1 mv, peak deviation) ........................≥ 115 dBATHD .............................................................................≤ 0.9 %Max. input voltage (SK) microphone/line ........3 vrmsInput impedance (SK) microphone/line ...........40 k O, unbalanced/1 M OInput capacitance (SK) ..........................................switchableAdjustment range of input sensitivity .............. S K: 60 dB, adjustable in steps of 3 dBSKM: 48 dB, adjustable in steps of 6 dBIn compliance with .................................................. C E, FCC, IC, ETS 300422, ETS 300445OvERALL DEvICETemperature range .................................................−10 °C to + 55 °CPower supply ........................................................... 2 AA size batteries, 1.5 v orBA 2015 accupackNominal voltage .....................................................2.4 vCurrent consumption: at nominal voltage ........typ. 180 mA (30 mW)with switched-off transmitter .............................≤ 25 μAOperating time .......................................................typ. 8 hrsDimensions ............................................................... S K: approx. 82 x 64 x 24 mmSKM: approx. Ø 50 x 265 mmWeight (incl. batteries) ......................................... S K: approx. 160 gSKM: approx. 450 gIn compliance with .................................................. C E, FCC, IC, ETS 300422, ETS 300445Continued on page 7Microphones (SK 300)ME 2ME 3-ew ME 4Microphone type .............................condenser condenser condenserSensitivity .........................................20 mv/Pa 1.6 mv/Pa40 mv/PaPick-up pattern ................................omni-directional cardioid cardioidMax. SPL ............................................130 dB SPL150 dB SPL120 dB SPL Microphone heads (SKM 300)MMD 835-1MMD 845-1MMK 865-1Radio microphone type .................dynamic dynamic condenserSensitivity ......................................... 2.1 mv/Pa 1.6 mv/Pa 1.6 mv/PaPick-up pattern ................................cardioid super-cardioid cardioid/super-cardioid,switchableMax. SPL ............................................154 dB SPL154 dB SPL152 dB SPL Frequency response .......................80.....18,000 Hz80.....18,000 Hz80.....18,000 HzDELIVERY INCLUDES for ew 312 / ew 322 / ew 352 G31 EM 300 G3 rack-mount receiver1 SK 300 G3 bodypack transmitter1 ME2 clip-on microphone (omni-directional) or1 ME 4 clip-on microphone (cardioid) or1 ME 3-ew headset microphone (cardioid)1 GA 3 rack mount1 NT2 power supply unit2 Antennas2 AA batteries1 Instruction manualDELIVERY INCLUDES for ew 335 / ew 345 / ew 365 G31 S KM 300-835 handheld transmitterwith cardioid dynamic head or1 S KM 300-845 handheld transmitterwith super-cardioid dynamic head or1 S KM 300-865 handheld transmitterwith super-cardioid condenser head1 EM 300 G3 rack receiver1 MZQ 1 microphone clip1 NT2 power supply unit2 Antennas1 GA 3 Rack mount kit2 AA batteries1 Instruction ManualPOLAR PATTERN0510152025dB30°30°60°60°90°90°120°150°120°150°0°180°125 Hz 250 Hz 500 Hz 1000 Hz2000 Hz 4000 Hz 8000 Hz 16000 HzMMD 835-1MME 865-1MMD 845-10510152025dB30°30°60°60°90°90°120°150°120°150°0°180°125 Hz 250 Hz 500 Hz 1000 Hz2000 Hz 4000 Hz 8000 Hz 16000 Hz0510152025dB30°30°60°60°90°90°120°150°120°150°0°180°125 Hz 250 Hz 500 Hz 1000 Hz2000 Hz 4000 Hz 8000 Hz 16000 HzME 3-ewME 4-ew0510152025dB30°30°60°60°90°90°120°150°120°150°0°180°125 Hz 250 Hz 500 Hz 1000 Hz2000 Hz 4000 Hz 8000 Hz 16000 Hz0510152025dB30°30°60°60°90°90°120°150°120°150°0°180°125 Hz 250 Hz 500 Hz 1000 Hz2000 Hz 4000 Hz 8000 Hz 16000 HzPRODUCT VARIANTSew 312 G3 Presentation Set Cat. No. ew 312 G3-A-EU 516 – 558 MHz 503112 ew 312 G3-A-US 516 – 558 MHz 503330 ew 312 G3-G-EU 566 – 608 MHz 503331 ew 312 G3-G-US 566 – 608 MHz 503332 ew 312 G3-B-EU 526 – 668 MHz 503333 ew 312 G3-B-US 526 – 668 MHz 503334 ew 312 G3-C-EU 734 –776 MHz 503335 ew 312 G3-C-US 734 –776 MHz 503336 ew 312 G3-D-EU 780 – 822 MHz 503337 ew 312 G3-D-EU-X 780 – 822 MHz 503338 ew 312 G3-D-UK 780 – 822 MHz 503339 ew 312 G3-E-EU 823 – 865 MHz 503340 ew 312 G3-E-EU-X 823 – 865 MHz 503341 ew 312 G3-E-UK 823 – 865 MHz 503342 ew 312 G3-GB 606 – 648 MHz 504649 ew 322 G3 Presentation Set Cat. No. ew 322 G3-E-UK 823 – 865 MHz 503357 ew 322 G3-A-EU 516 – 558 MHz 503113 ew 322 G3-A-US 516 – 558 MHz 503345 ew 322 G3-G-EU 566 – 608 MHz 503346 ew 322 G3-G-US 566 – 608 MHz 503347 ew 322 G3-B-EU 626 – 668 MHz 503348 ew 322 G3-B-US 626 – 668 MHz 503349 ew 322 G3-C-EU 734 –776 MHz 503350 ew 322 G3-C-US 734 –776 MHz 503351 ew 322 G3-D-EU 780 – 822 MHz 503352 ew 322 G3-D-EU-X 780 – 822 MHz 503353 ew 322 G3-D-UK 780 – 822 MHz 503354 ew 322 G3-E-EU 823 – 865 MHz 503355 ew 322 G3-E-EU-X 823 – 865 MHz 503356 ew 322 G3-GB 606 – 648 MHz 504650 ew 352 G3 Presentation Set Cat. No. ew 352 G3-A-EU 516 – 558 MHz 503114 ew 352 G3-A-US 516 – 558 MHz 503360 ew 352 G3-G-EU 566 – 608 MHz 503361 ew 352 G3-G-US 566 – 608 MHz 503362 ew 352 G3-B-EU 526 – 668 MHz 503363 ew 352 G3-B-US 526 – 668 MHz 503364 ew 352 G3-C-EU 734 –776 MHz 503365 ew 352 G3-C-US 734 –776 MHz 503366 ew 352 G3-D-EU 780 – 822 MHz 503367 ew 352 G3-D-EU-X 780 – 822 MHz 503368 ew 352 G3-D-UK 780 – 822 MHz 503369 ew 352 G3-E-EU 823 – 865 MHz 503370 ew 352 G3-E-EU-X 823 – 865 MHz 503371 ew 352 G3-E-UK 823 – 865 MHz 503372 ew 352 G3-GB 606 – 648 MHz 504651ew 335 G3 Vocal Set Cat. No. ew 335 G3-A-EU 516 – 558 MHz 503115 ew 335 G3-A-US 516 – 558 MHz 503375 ew 335 G3-G-EU 566 – 608 MHz 503376 ew 335 G3-G-US 566 – 608 MHz 503377 ew 335 G3-B-EU 526 – 668 MHz 503378 ew 335 G3-B-US 526 – 668 MHz 503379 ew 335 G3-C-EU 734 –776 MHz 503380 ew 335 G3-C-US 734 –776 MHz 503381 ew 335 G3-D-EU 780 – 822 MHz 503382 ew 335 G3-D-EU-X780 – 822 MHz 503383 ew 335 G3-D-UK 780 – 822 MHz 503384 ew 335 G3-E-EU 823 – 865 MHz 503385 ew 335 G3-E-EU-X823 – 865 MHz 503386 ew 335 G3-E-UK 823 – 865 MHz 503387 ew 335 G3-GB 606 – 648 MHz 504652 ew 345 G3 Vocal Set Cat. No. ew 345 G3-A-EU 516 – 558 MHz 503116 ew 345 G3-A-US 516 – 558 MHz 503390 ew 345 G3-G-EU 566 – 608 MHz 503391 ew 345 G3-G-US 566 – 608 MHz 503392 ew 345 G3-B-EU 526 – 668 MHz 503393 ew 345 G3-B-US 526 – 668 MHz 503394 ew 345 G3-C-EU 734 –776 MHz 503395 ew 345 G3-C-US 734 –776 MHz 503396 ew 345 G3-D-EU 780 – 822 MHz 503397 ew 345 G3-D-EU-X780 – 822 MHz 503398 ew 345 G3-D-UK 780 – 822 MHz 503399 ew 345 G3-E-EU 823 – 865 MHz 503400 ew 345 G3-E-EU-X823 – 865 MHz 503401 ew 345 G3-E-UK 823 – 865 MHz 503402 ew 345 G3-GB 606 – 648 MHz 504653 ew 365 G3 Vocal Set Cat. No. ew 365 G3-A-EU 516 – 558 MHz 503117 ew 365 G3-A-US 516 – 558 MHz 503405 ew 365 G3-G-EU 566 – 608 MHz 503406 ew 365 G3-G-US 566 – 608 MHz 503407 ew 365 G3-B-EU 526 – 668 MHz 503408 ew 365 G3-B-US 526 – 668 MHz 503409 ew 365 G3-C-EU 734 –776 MHz 503410 ew 365 G3-C-US 734 –776 MHz 503411 ew 365 G3-D-EU 780 – 822 MHz 503412 ew 365 G3-D-EU-X780 – 822 MHz 503413 ew 365 G3-D-UK 780 – 822 MHz 503414 ew 365 G3-E-EU 823 – 865 MHz 503415 ew 365 G3-E-EU-X823 – 865 MHz 503416 ew 365 G3-E-UK 823 – 865 MHz 503417 ew 365 G3-GB 606 – 648 MHz 504654RECOMMENDED ACCESSORIESCat. No. ME 4-ew – Clip-on microphone,cardioid, black 503156 AM 2 – Antenna Mount kit 009912 CC 3 – System Case 503168L 2015 – Charging unit 009928 BA 2015 – Rechargeable battery pack 009950 ASA 1 – Active antenna splitter 503165 NT 1-1 – plug-in mains unit forASA 1 & L 2015 E U: 503158US: 503873UK: 503874 NT 3-1 – Plug-in mains unit for L 2015 E U: 503159US: 503876UK: 503877 A 1031-U – Antenna 004645A 2003-UHF – Directional Antenna 003658 AB 3 – Antenna booster 505550 Ear Set 1-ew – Ear-worn microphone,omni, black 504232 Ear Set 1-ew-3 – Ear-worn microphone,omni, beige 504237 Ear Set 4-ew – Ear-worn microphone,cardioid, black 504236 Ear Set 4-ew-3 – Ear-worn microphone,cardioid, beige 504234 MKE 1-ew – Clip-on microphone,omni-directional, black 502876 MKE 1-ew-1 – Clip-on microphone,omni, white 502877 MKE 1-ew-2 – Clip-on microphone,omni, brown 502878 MKE 1-ew-3 – Clip-on microphone, beige 502879 MKE 2-ew Gold – Clip-on microphone,omni, black 009831 MKE 2-ew-3 Gold – Clip-on microphone,omni, beige 009832 MKE 40-ew – Clip-on microphone,cardioid, black 500527Cat. No. HSP 4-ew – Headworn microphone,cardioid, black 009864 HSP 4-ew-3 – Headworn microphone,cardioid, beige 009867 HSP 2-ew – Headworn microphone,omni, black 009866 HSP 2-ew-3 – Headworn microphone,omni, beige 009872 CI 1 – Instrument cable 503163ew 335 / ew 345 / ew 365 G3 Vocal SetsMMD 835-1 – evolution microphone head 502575 MMD 845-1 – evolution microphone head 502576 MME 865-1 – evolution microphone head 502581 MZW 1 – Windshield 004839 KEN 2 – Identification rings 530195 LA 2 – Charging adapter forhandheld microphones 503162 CC 3 – System case 503168Sennheiser electronic GmbH & Co. KG Am Labor 1, 30900 Wedemark, Germany 0 4 / 1 3 S e n n h e i s e r i s a r e g i s t e r e d t r a d e m a r k o f S e n n h e i s e r e l e c t r o n i c G m b H & C o . K G . w w w . s e n n h e i s e r . c o m . C o p y r i g h t ©0 4 / 2 0 1 3 . A l l r i g h t s r e s e r v e d . E r r o r s a n d o m i s s i o n s e x c e p t e d .Contact your local Service Partner:。

HCDP英文版判断题

HCDP英文版判断题

1. a device can be assigned an IP address 192.168.13.175,with the mask being 255.255.255.240True FalseFalse2.an ospf hello message carries a list of known neighborsTrue FalseTrue3.only router-LSAs and Network-LSAs are involved in intra-area route calculationsTrue FalseTrue4.only one BGP process can be configured on a routerTrue FalseTrue5.an ip-prefix-filter is used to filter ip prefixes and data packetsTrue FalseFalse6.RSTP has all functions that STP has and it is backward compatible with STP.True FalseTrue7.TO enable an eudemon in routing mode to work like a router,you need to assign ip addressesto interfaces and enable dynamic or static routing protocols on the eudemon.True FalseTrue8.The eudemon that is working in transparent mode detects processes data at layer 2.Itsinterfaces are not configured with ip addresses.True FalseTrue9.When an eudemon is working in composite mode,some of its interfaces are configured withip addresses (Layer 3 interfaces) and the other interfaces are not configured with ip addresses(Layer 2 interafces). To enable dual-system hot backup on an eudemon,you can configure the eudemon to work in composite mode.True FalseTrue10.Two Eudemons in dual-system hot backup can be working in active-active mode oractive-standby mode.True FalseTrue11.The eudemon supports load balancing between multiple uplinks.True FalseTrue12.Different virtual firewall instances on an Eudemon must be configured with the same securitypolicy.True FalseFalse13.The firewall can be working in routing mode, transparent mode,or composite mode. Thedefault mode is the composite mode.True FalseFalse14.Virtual firewalls on the Eudemon are not allowed to access each other by default unless asecurity policy is specified.True FalseTrue15.IP addresses added to the blacklist of the Eudemon cannot be deleted.True FalseFalse16.You cannot set an aging time for the blacklist of the Eudemon.True FalseFalse17.The Eudemon generates a blacklist upon detecting an attack.True FalseFalse18.The Eudemon can control traffic and connections based on IP addresses.True FalseTrue19.The firewall does not use security rules to filter packets exchanged between interfaces in thesame zone.True FalseTruework address translation (NAT) translates only IP address information.True FalseFalse21.IP unnumbered is to borrow an IP address from an interface.If an interface has multiple IPaddresses,all its IP addresses will be borrowed and the primary address will continue after these IP addresses are borrowed.True FalseFalse22.When two Eudemon are working in dual-system hot backup mode,their session tables arebacked up in real time.True FalseTrue23.After an interface on a firewall is added to a zone, the interface belongs to the zone.True FalseTrue24.Status detection is an advanced communication filtering mechanism.It checks the applicationlayer protocol and monitors the status of the connection-based application layer protocol.For all connections,the status information about each connection is maintained by ASPF and is used to dynamically determine whether to permit or deny data packets to firewalls.True FalseTrue25.The NAT multi-instance function on the Eudemon independently maintains a NAT table foreach instance to provide address translation services for instances.True FalseTrue26.The IPSec function on the Eudemon supports NAT traversal.True FalseTrue27.The NAT function enabled on the Eudemon does not greatly affect system performance.True FalseTrue28.The Eudemon does not support port mapping.True FalseFalse29.In a Land attack,the source address and destination address of an SYN packet are both the IPaddress of the attacked object or a loopback address.True FalseTrue30.The association between the IDS and firewall requires that the IDS be directly connected tothe firewall.True FalseFalse31.Security policies for the firewall are applied to interzones but not to interfaces.True FalseTrue32.The multi-channel protocol is used to establish at least two channels(sessions) forcommunications or services.True FalseTrue33.ICMP packets are sent in a smurf attack and UDP packets are sent in a Fraggle attack.True FalseTrun34.The urgent pointer in the flag field of an IPv4 packet header is generally used for 00B datatransmission.True FalseTrue35.A firewall filters packets exchanged between zones but does not filter packets exchangedbetween intefaces in the same zone.True FalseTrue36.Two Eudemon in dual-system hot backup mode can be working in active-active mode oractive-standby mode.True FalseTrue37.Two Eudemon in dual-system hot backup mode use Huawei Redundancy Protocol(HRP) toback up key information (such as configuration commands and session status) between the active and standby devices.True FalseTrue38.The Eudemon uses the blacklist technology to associate with an NIP IDS.True FalseTrue39.Qos provides services of different qualities to meet various applicationrequirements,including dedicated bandwidth, decreased packet loss ratio,short packet transmission delay, and decreased delay and jitter.True FalseTrue40.In traffic shaping,the packet whose transmission rate exceeds the rate limit will be discardedor re-markedTrue FalseFalse41.WFQ can effectively control the delay and jitter by means of configuring weights for differentservices.True FalseTrue42.Congestion occurs when a link or node is carrying so much data that its quality of servicedeteriorates.True FalseTrue43.Most fields in IP headers of packets in the same data flow are identical,You can compressthese fields to improve the link transmission.True FalseTrue44.The variation in packet delay is called jitter.True FalseTrue45.The end-to-end delay is the sum of transmission delays,processing delays,and queuing delaysalong the packet forwarding path.True FalseTrue46.The data transmission rate depends on the bandwidth.True FalseTrue47.Packet loss occurs only on the packet receiverTrue FalseFalse48.Based on specific rules,traffic classification identifies packets having the same characteristics,Traffic classification is the prerequisite and basis for differentiated services.True FalseTrue49.Congestion management provides means to manage and control traffic when trafficcongestion occurs.True FalseTrue50.The traditional packet loss policy uses the Tail-Drop method.True FalseTrue51.The IP packet has a special field to mark the Qos. For example,the last 6 bits in the Tos field ofan IPv4 packet mark the DSCP value.True FalseFalse52.In traffic shaping, the packet whose transmission rate exceeds the rate limit will be discardedor re-marked.True FalseFalse53.WFQ can effectively control the delay and jitter by means of configuring weights for differentservices.True FalseTrue54.Congestion occurs when a link or node is carrying so much data that its quality of servicedeteriorates.True FalseTrue55.Most fields in IP headers of packets in the same data flow are identical. You can compressthese fields to improve the link transmission efficiency.True FalseTrueplex traffic classification matches packets with rules and then takes actions to matchingpackets.True FalseTrue57.Traffic shaping usually buffers packets that need to be dropped by traffic policing by means ofbuffer and token bucket.True FalseTrue58.In traffic policing using two token buckets,tokens are put into the CBS bucket at thecommitted information rate(CIR),The peak burst size(PBS) bucket is filled in only after the CBS bucket is full.True FalseTrue59.The interface IP address and virtual IP address configured for VRRP must not be identical.True FalseFalse60.A VRRP virtual router can have one or more IP addresses.True FalseTrue61.The virtual router uses a virtual MAC address but not the actual MAC address of the interfaceto respond to an ARP request.True FalseTrue62.A VRRP backup group is able to track the status of an interface. If the interface configuredwith a VRRP backup group fails or any interface on the router fails,the VRRP backup group providesTrue FalseTrue63.By using VRRP, the backup router in a VRRP backup group immediately becomes the masterrouter after detecting a fault and instructs its attached hosts to perform a master/slave switchover accordingly. This ensures that services will recover within a short period of time.True FalseFalse64.The reliability of a product or a system is generally evaluated with the two indicators of Meantime to repair (MTTR) and mean time between failures(MTBF).True FalseTrue65.BFD detects the link status immediately after a BFD session is set up .if BFD parameters aremodified or deleted at one end of the BFD session,the other end will consider such a modification or deletion as a fault and services will be then affected, Therefore,exercise caution when modifying or deleting BFD parameters.True FalseFalse66.One CV packet per second is generated on the ingress LSR of the LSP and receivd by theegress LSR, this generation rate is low and allows no adjustment,hence,the CV packet is usually used for checking the availability of a common LSP.True FalseTrue67.BFD packets are classified into control packets and echo packets.True FalseTrue68.A BFD session is set up following the three-way handshake during which parameters for theBFD session are negotiated. After the BFD session is set up,modifying the detection time parameters does not take effect.True FalseFalse69.The NSF function takes effect only after the GR function is enabled on two directly connectedrouters that use static routes for communication between users in different network segments.True FalseFalse70.During the GR of dynamic routing protocols(such as OSPF and BGP)neighbor relationshipsremain unchanged.True FalseFalse71.BFD is a common fast detection technology,It implements the fast switchover function onlywhen collaborating with other fast switchoverTrue FalseTrue72.BFD (a fast detection technology) enabled on a device quickly identifies a fault and reportsthe fault to the appropriate protocol modele after detecting a master/slave switchover on the neighboring devic,this causes the protocol module to quit the GR. AS such,BFD and GR cannot be used together.True FalseFalse73.In OSPF,the process of calculating shortest path tree can be divided into two phases,calculatetransit node first,then calculate stub network.True FalseFalse74.In the process of calculating SPF tree,the cost from a node to root node equals to metriclisted in the Router LSA generated by the node.True FalseFalse75.BGP is an exterior gateway protocol,which runs among Ass,It focuses on routes control andselection of optimal routes rather than discovery and calculation of routes.True FalseTrue76.OSPF supports the combination of a group of network segments.Such a group is also calledan area.In other words,an area is a set of network segments.True FalseTrue77.The value of ospf dr-priority ranges from 0 to 255 and the default value is 64.True FalseFalse78.A broadcast and an NBMA network.each having two or more routers,must both have a DRand a BDR.True FalseFalse79.The vlink-peer command is used to specify a peer IP address for setting up a virtual link.True FalseFalse80.Different types of networks cannot establish an adjacency in the Full state.True FalseFalse81.Different network segments can be in the same OSPF area and the same network segmentcan be in different OSPF areas.True FalseFalse82.OSPF supports two authentication modes:area authentication and interfaceauthentication.The two authentication modes cannot be configured at the same time.True FalseFalse83.Each router running OSPF has a router ID,A router ID is a 32-bit integer and uniquelyidentifies a router,Hence,even of routers in different Ass,the router IDs must be different.True FalseFalse84.The most remarkable characteristic of OSPF is that OSPF supports the link-state algorithm.True FalseTrue85.OSPF directly runs over the IP protocol,Its IP protocol number is 89True FalseTrue86.If the Router Priority of a router is set to 0,this router cannot be elected as a DR or a BDR.True FalseTrue87.On a non-broadcast network,OSPF has two operating modes:NBMA and P2MPTrue FalseTrue88.By default,the cost of an OSPF interface is related to interface bandwidth.The algorithm forcalculating the cost is:True FalseTrue89.On a broadcast network or an NBMA network,not all neighbors need to set upadjacencies.Therefore,the concept about the adjacency is applicable to only the broadcast network or the NBMA network.True FalseFalse90.The NBMA mode requires all the routers in the network to be fully connected:otherwise,itdoes not function.True FalseFalse91.When two routers exchange LSDB information by exchanging DD packets,a master/slaverelationship is established between the two routers,The router with a larger router ID is the master.True FalseTrue92.If both the ospf cost and bandwidth-reference commands are configured on an interface.thevalue set in the ospf cost command is used as the cost of the interface.True FalseFalse93.The bandwidth-reference parameter is measured in Mbit/sTrue FalseTrue94.The asbr-summary command only contains the not-advertise parameter but not theadvertise parameter.True FalseTrue95.Each DD packet has a DD sequence number for packet acknowledgment.A DD sequencenumber is two-byte long.True FalseTrue96.On a broadcast network or an NBMA network,a router with a higher Router Priority is electedas a DR.True FalseFalse97.The LS Sequence Number field is used to detect expired and duplicate LSAs,This field is asigned 32-bit integer and therefore the minimum LS Sequence Number is 0x80000000True FalseFalse98.The LSAs with the same LS Sequence Number and LS age are the same LSA.True FalseFalse99.ABRs of a Stub area do not flood type-5 and type-4 LSAs to the stub area.Therefore,the stubarea does not have the external AS routing capability.ABRs of the stub area advertise a default route to the stub area to guide packet forwarding to the external of the AS.True FalseTrue100.The ABR in a Totally Stubby area will not advertise Type-3,Type-4,and Type-5 LSAs to the Totally Stubby area.Instead,the ABR will advertise a default route to the Totally Stubby area to guide forwarding of packets destined for other areas.True FalseTrue101.The ABR of an NSSA will not advertise Type-4 and Type-5 LSAs to an NSSA but can import external routes into the NSSA.True FalseTrue102.Different from a Stub area,an NSSA supports Type-5 LSAs.True FalseFalse103.ABRs advertise link status information about connected non-backbone areas to the backbone area.The backbone area then advertises the routing information about the backbone area cannot be advertised to non-backbone ares.True FalseFalse104.Type 2-external routes always take precedence over type 1-external routes True FalseFalse105.The import-route limit command is used to set the maximum number of external routers that can be imported into an OSPF process.True FalseTrue106.An Autonomous System (AS) is a set of routers under a single technical administration,using the same routing policy.True FalseTrue107.BGP peers are automatically discovered by exchanging multicast packets.True FalseFalse108.The router ID configured in the system view takes precedence over the router ID configured in the BGP view.True FalseFalse109.A failure in establishing a BGP peer relationship can be addressed by checking the TCP connectivity and BGP peer configurations.True FalseTrue110.In BGP,performing MD5 authentication between BGP peers can protect them from Dos attacks.True FalseTrue111.In the VRP,by default,the routes imported by BGP are not automatically summarized.True FalseTrue112.Based on BGP route selection rules,a local route that is automatically summarized takes precedence over a local route that is manually summarized.True FalseFalse113.Once a BGP connection is established,a BGP speaker advertises all the optimal routes in the BGP routing table to its BGP peer.True FalseTrue114.Whatever changes occur in the BGP routing table,a BGP speaker advertises all the optimal routes in the BGP routing table to its BGP peerTrue FalseFalse115.In the VRP,by default,a BGP router automatically retransmits an Update packet to its BGP peer after the outbound routing policy of the BGP peer changes.True FalseTrue116.IGP routes can be installed into the BGP routing table by running either the network or import-route command.True FalseTrue117.In the VRP,by default,a BGP router does not automatically send a Refresh to request its BGP peer to retransmit an Update packet after the inbound routing policy of the BGP peer changes.True FalseFalseing the peer connect-interface command to establish multiple peer relationships between two routers connected through multiple links is recommended.True FalseTrue119.Based on BGP route selection rules,the route with the lowest local-preference is preferred.True FalseFalse120.Based on BGP route selection rules,the route with the smallest MED value is preferred.True FalseTrue121.The origin attribute of the BGP route that is imported by using the network command is IGP True FalseTrue122.The BGP community attribute is a well-known mandatory attribute.True FalseFalse123.An ACL is used to match routing information or data packet addresses so as to filter out the unmatched routing information or data packets.True FalseTrue124.The system can perform ACL rule matching only based on the configuration order of rules.True FalseFalse125.Generally,the performance of an IP-prefix-filter is higher than that of an ACL.True FalseTrue126.An AS-path-filter is used to filter as-path attributes of BGP routes.The as-path attribute is actually a character string defined by using a regular expression.True FalseTrue127.Default routes between routers are a low-cost solution.this is because using default routes requires less system resources than maintaining a complete routing table.True FalseTrue128.An AS-path-filter uses the regular expression[0-9]+$ to indicate all as-path attributes.True FalseFalse129.Regular expressions can be used in both the community-filter and AS-path-filter to define the attribute mode used for route filteringTrue FalseTrue130.Route filtering can filter not only routing information but also link-status information.True FalseFalse131.For link-status routing protocols,filtering routes in the inbound direction actually cannot block the transmission of link-status information.the filtering effect is that routes cannot be injected into the local routing table but neighbors can still receive complete route status information and calculate complete routes.True FalseTrue132.All routing protocols can deliver default routes,supporting both forcible delivery and non-forcible delivery.True FalseFalse133.IF different routing protocols run on different networks and these networks need to share routing information,route importing can be usedTrue FalseTrue134.The route selection tool route-policy can filter and set BGP attributes based on pre-defined conditions.therefore,this tool is commonly used to define policies for BGP peers and often used in routeTrue FalseTrue135.When importing routes discovered by other routing protocols,a routing protocol may need to import only the routes that meet the conditions and set attributes of the imported routes to meet the requirement of the protocol,In such a case,a route-policy can be created.True FalseTrue136.Policy-based routing and routing policy affect the forwarding of data packets in different ways:A routing policy mainly controls packet forwarding,According to the routing policy,packets can be forwarded with no need to use a routing table:policy-based routing mainly controls the importing,advertising,and receiving of routing information so as to affect the forwarding of data packets.True FalseFalse137.The unicast and multicast technologies are both outstanding in solving the problem of one source and multiple destinations for efficient P2MP data transmission.True FalseFalse138.The IGMP protocol runs between a host and its directly connected multicast router.True FalseTrueyer 3 switch has layer 2 capability as well as layer 3 routing capabilityTrue FalseTrue140.STP distributes configuration message by sending BPDU packet to each other True FalseTrue141.A switching network has been enabled with STP protocol.To provide fast access speed to the file server for most of the users,the switch that is directly connected with file server is configured as the root bridgeTrue FalseTrue142.IF loop exists and STP is not enabled,the switch will not operate normally True FalseTrue143.RSTP adopts fast convergence mechanism,So,there is no forward delay interval in RSTP True FalseFalse144.Two switches are directly connected to each other and they are working in full duplex mode.By default,RSTP will consider the link between the switches as point-to-point linkTrue FalseTrue145.In RSTP network environment,a port can be set as edge port when it is directly connected with terminalTrue FalseTrue146.In a switching network that runs RSTP,the topology change notification message will not be sent when the switch detects that the Alternate port is faile.True FalseTrue147.VLANs isolate broadcast domains,eliminates broadcast storms,and enhances information securityTrue FalseTrue148.Before establishing a network,we must create VLANs,the users that do not need to communicate with each other should be added to the same VLAN for isolationTrue FalseFalse149.The port isolation function can isolate the ports on the same switchTrue FalseTrue150.When configuring VLAN mapping,you must set the priority of outer VLAN ID True FalseFalse151.On a switch running GVRP,each interface is considered as a participant.the participants can exchange informationTrue FalseTrue152.A switching network has been enabled with STP protocol,To provide fast access speed to the file server for most of the users,the switch that is directly connected with file server isconfigured as the root bridgeTrue FalseTrue153.When configuring VLAN mapping,you must set the priority of outer VLAN ID True FalseFalse154.QinQ provides a simplified layer 2 VPN tunnelTrue FalseTrue155.The STP protocol cannot prevent MAC address table flapping caused by loops on the layer 2 networkTrue FalseFalse156.According to the MSTP protocol,each MST instance calculates an independent spanning tree by using the RSTP algorithmTrue FalseTrue157.The traditional antivirus system prevents viruese on each node separately and may fail to prevent many security threatsTrue FalseTrue158.NAC is an end-to-end security solution.it protects network security from user terminals instead of network devicesTrue FalseTrue159.If 802.1x authentication is enabled on an interface,MAC address authentication (enabled by the mac-authen enable command) and direct authentication(enabled by the direct-authen enable command) cannot be enabled on the interfaceTrue FalseTrue160.The option field in DHCP messages uses the CLV modeTrue FalseTrue161.The option field in DHCP messages has a fixed length of four bytesTrue FalseFalse162.If only some devices on a network run MPLS (MPLS domain is encapsulated in the IP packet header),labels are generated only for direct routes of devices running bels are not generated for the routes originated from other devices running IP protocolsTrue FalseTrue163.The core of the MPLS technology is label switching.True FalseTrue164.In MPLS VPN configuration,you can choose from various types of routing protocols to configure between PEs and CEs.any type of routes can be imported to a VPN instance by using the import commandTrue FalseTrue165.VRF refers to VPN instance.It is an entity that a PE maintains for its directly connected site True FalseTrue166.On an MPLS VPN network,CEs and PEs can use the same routing protocol or different routing protocols to exchange routing information,the routing protocols are independent from one anotherTrue FalseTrue。

CCF推荐的国际学术会议和期刊目录修订版发布

CCF推荐的国际学术会议和期刊目录修订版发布

CCF推荐的国际学术会议和期刊目录修订版发布CCF(China Computer Federation中国计算机学会)于2010年8月发布了第一版推荐的国际学术会议和期刊目录，一年来，经过业内专家的反馈和修订，于日前推出了修订版，现将修订版予以发布。

本次修订对上一版内容进行了充实，一些会议和期刊的分类排行进行了调整，目录包括：计算机科学理论、计算机体系结构与高性能计算、计算机图形学与多媒体、计算机网络、交叉学科、人工智能与模式识别、软件工程/系统软件/程序设计语言、数据库/数据挖掘/内容检索、网络与信息安全、综合刊物等方向的国际学术会议及期刊目录，供国内高校和科研单位作为学术评价的参考依据。

目录中，刊物和会议分为A、B、C三档。

A类表示国际上极少数的顶级刊物和会议，鼓励我国学者去突破；B类是指国际上著名和非常重要的会议、刊物，代表该领域的较高水平，鼓励国内同行投稿；C类指国际上重要、为国际学术界所认可的会议和刊物。

这些分类目录每年将学术界的反馈和意见，进行修订，并逐步增加研究方向。

中国计算机学会推荐国际学术刊物（网络/信息安全）一、 A类序号刊物简称刊物全称出版社网址1. TIFS IEEE Transactions on Information Forensics andSecurity IEEE /organizations/society/sp/tifs.html2. TDSC IEEE Transactions on Dependable and Secure ComputingIEEE /tdsc/3. TISSEC ACM Transactions on Information and SystemSecurity ACM /二、 B类序号刊物简称刊物全称出版社网址1. Journal of Cryptology Springer /jofc/jofc.html2. Journal of Computer SecurityIOS Press /jcs/3. IEEE Security & Privacy IEEE/security/4. Computers &Security Elsevier http://www.elsevier.nl/inca/publications/store/4/0/5/8/7/7/5. JISecJournal of Internet Security NahumGoldmann. /JiSec/index.asp6. Designs, Codes andCryptography Springer /east/home/math/numbers?SGWID=5 -10048-70-35730330-07. IET Information Security IET /IET-IFS8. EURASIP Journal on InformationSecurity Hindawi /journals/is三、C类序号刊物简称刊物全称出版社网址1. CISDA Computational Intelligence for Security and DefenseApplications IEEE /2. CLSR Computer Law and SecurityReports Elsevier /science/journal/026736493. Information Management & Computer Security MCB UniversityPress /info/journals/imcs/imcs.jsp4. Information Security TechnicalReport Elsevier /locate/istr中国计算机学会推荐国际学术会议（网络/信息安全方向）一、A类序号会议简称会议全称出版社网址1. S&PIEEE Symposium on Security and Privacy IEEE /TC/SP-Index.html2. CCSACM Conference on Computer and Communications Security ACM /sigs/sigsac/ccs/3. CRYPTO International Cryptology Conference Springer-Verlag /conferences/二、B类序号会议简称会议全称出版社网址1. SecurityUSENIX Security Symposium USENIX /events/2. NDSSISOC Network and Distributed System Security Symposium Internet Society /isoc/conferences/ndss/3. EurocryptAnnual International Conference on the Theory and Applications of Cryptographic Techniques Springer /conferences/eurocrypt2009/4. IH Workshop on Information Hiding Springer-Verlag /~rja14/ihws.html5. ESORICSEuropean Symposium on Research in Computer Security Springer-Verlag as.fr/%7Eesorics/6. RAIDInternational Symposium on Recent Advances in Intrusion Detection Springer-Verlag /7. ACSACAnnual Computer Security Applications ConferenceIEEE /8. DSNThe International Conference on Dependable Systems and Networks IEEE/IFIP /9. CSFWIEEE Computer Security Foundations Workshop /CSFWweb/10. TCC Theory of Cryptography Conference Springer-Verlag /~tcc08/11. ASIACRYPT Annual International Conference on the Theory and Application of Cryptology and Information Security Springer-Verlag /conferences/ 12. PKC International Workshop on Practice and Theory in Public Key Cryptography Springer-Verlag /workshops/pkc2008/三、 C类序号会议简称会议全称出版社网址1. SecureCommInternational Conference on Security and Privacy in Communication Networks ACM /2. ASIACCSACM Symposium on Information, Computer and Communications Security ACM .tw/asiaccs/3. ACNSApplied Cryptography and Network Security Springer-Verlag /acns_home/4. NSPWNew Security Paradigms Workshop ACM /current/5. FC Financial Cryptography Springer-Verlag http://fc08.ifca.ai/6. SACACM Symposium on Applied Computing ACM /conferences/sac/ 7. ICICS International Conference on Information and Communications Security Springer /ICICS06/8. ISC Information Security Conference Springer /9. ICISCInternational Conference on Information Security and Cryptology Springer /10. FSE Fast Software Encryption Springer http://fse2008.epfl.ch/11. WiSe ACM Workshop on Wireless Security ACM /~adrian/wise2004/12. SASN ACM Workshop on Security of Ad-Hoc and Sensor Networks ACM /~szhu/SASN2006/13. WORM ACM Workshop on Rapid Malcode ACM /~farnam/worm2006.html14. DRM ACM Workshop on Digital Rights Management ACM /~drm2007/15. SEC IFIP International Information Security Conference Springer http://sec2008.dti.unimi.it/16. IWIAIEEE International Information Assurance Workshop IEEE /17. IAWIEEE SMC Information Assurance Workshop IEEE /workshop18. SACMATACM Symposium on Access Control Models and Technologies ACM /19. CHESWorkshop on Cryptographic Hardware and Embedded Systems Springer /20. CT-RSA RSA Conference, Cryptographers' Track Springer /21. DIMVA SIG SIDAR Conference on Detection of Intrusions and Malware and Vulnerability Assessment IEEE /dimva200622. SRUTI Steps to Reducing Unwanted Traffic on the Internet USENIX /events/23. HotSecUSENIX Workshop on Hot Topics in Security USENIX /events/ 24. HotBots USENIX Workshop on Hot Topics in Understanding Botnets USENIX /event/hotbots07/tech/25. ACM MM&SEC ACM Multimedia and Security Workshop ACM。

5G基站纳秒级时间同步技术分析

5G基站纳秒级时间同步技术分析

通信网络技术基站纳秒级时间同步技术分析高衡，王显，郑硕超（三维通信股份有限公司，浙江杭州网络中，各个基站之间需要精确的时间同步，以确保网络正常运行和提供高质量的服务。

因此，需要纳秒级时间同步技术，保证数据可以进行准确的传递，并且不会出现时间上的差异。

文章总结了基站纳米级时间同步的关键技术，分别是信号传输技术、信号测量技术及信号网络的性能和可靠性，使5G基站；纳秒级时间同步；信号调节Analysis of Nanosecond Time Synchronization Technology for 5G Base StationsGAO Heng, WANG Xian, ZHENG Shuochao(Sunwave Communications Co., Ltd., HangzhouG networks, precise time synchronization is required between base stations to ensure the normalhigh-quality services. This requires球导航卫星的定时功能是至关重要的一环。

这项技GLONASS、等）提供的定时信号，以确保基站之间的高精1所示，通过分析全球导航系统，可以找出最优的定时基站使用全球卫星导航系统的信号，这些系统由一系列卫星组成，通过向地面发送定时信号来提供全球范围的导航和定位服务。

基站需要将来自卫星系统的定时信号转化为纳米级别的时间同步，要求基站具备高度精密的时钟同步技术，以确保信号的准确传输和接收。

为保持信号的精度，基站使用先进的信号传输技术，通过适应性调整以应对信号传输应基站之间可能存在的时延差异，从而实现更精确的时间同步。

为进一步优化基站的时间同步，卫星可能会发送辅助的定时信号，帮助基站更精确地校准其本地时钟。

同步卫星双向定时技术在间同步中的意义在于可以实现双向的时间信息传递，使基站和卫星之间能够共同调整地优化时间同步。

人力资源管理PERFORMANC部分（英文课件）（已处理）

人力资源管理PERFORMANC部分（英文课件）（已处理）

Performance Management and Appraisal Main points Performance and performance management 360-Degree feedback Methods of individual performance appraisal Balanced scorecard Problems of PM and performance interview Performance Performance Organizational performance Individual performance OP NIP Criteria of performance What constitute the PMS Corporate level –the balanced scorecard Individual level – the performance appraisal Integrated process- linkage of the above with HRM practices such as setting goals training and development of employees pay benefits changes in job and organization design Performance Management System PMS focuses on creating and maintaining core competence at the organizational and individual level PMS maintains a strategic perspective on the interactions of various levers of change on peoples behavior Individual performance appraisal PA means evaluating an employees current or past performance relative to hisher performance standards Objectives of performance appraisal To motivate staff reward feedback To develop staff To provide essential mgt information eg Assessing overall training and development needs Capability and knowledge management 绩效管理和传统绩效考核的区别传统的绩效考核 1 事后控制2 自上而下没有反馈3 以人力资源部为主4 薪酬奖金绩效管理和传统绩效考核的区别 Choice of Raters Supervisor Advantages connected with promotion reward punishment stand at a higher point Disadvantagespsychological load due to connection with Reward Payment short of training for appraisal de-motivate employee if not appropriate Peer Advantages comprehensive real Disadvantages far away from truth due to competitiveness or afraid of hurting a friend Subordinate Advantages Help manager develop managerial skills balanced the managers power Disadvantages dare not tell the truth of hisher boss for fear of dismissal do not understand hisher boss work Self Advantages comprehensive not much stress good for improvement Disadvantages overestimate 90 think they are above average can not be the basis for promotion and incentive Customer Advantages objective good for customer-orientation Disadvantages NO uniform standard time cost energy cost Expert For high-level manager Cost is too high Points of 360 Degree Feedback Main objective develop not evaluate Key Criteria KPI related to organizational performance Train evaluators Quick feedback and communication Effective goal setting SMART Goal P157 Specific Absolute terms satisfactory completion Measurable Quantitative terms Attainable Challenging but not too difficult encourage employees participation Relevant Consistent with organizational objectives Timely reflect deadlines and milestones Employee comparison systems Graphic rating scales Behavior observation scales Behaviorally anchored rating scales Management-by-objectives Strengths Low cost Practical Time efficient Eliminates some rating errors Aids decision making Weaknesses Accuracy and fairness questionable Failto direct or monitor behavior Cross-departmental comparisons difficult Firms performance appraisals Balanced score card 创建人 Balanced score card 以财务性数据为主的绩效管理体系平衡计分卡的优缺点 Rating errors --Halo effect --Leniency--Strictness--Central tendency--Primacy--Recency--Contrast effects 1 Halo effect P169 Halo effect is where an evaluation on one dimension influences evaluation on all the others Lack of conscientiousness Vague performance standards 2 Leniency P169 Leniency problem is the process of evaluating someone too easily 3 Strictness P169 Error of strictness is the process of evaluating someone too harshly Political Lack of conscientiousness Vague performance standards 4 Central tendency P169 Error of central tendency is the process of evaluating all the employees about average on all dimensions Administrative procedures Poorly defined scales 5 Primacy bias Primacy bias is the bias of giving the first information greater weight Cannot observe all aspects of employees job performance Categorizing employees by type of person 6 Recency bias Recency bias gives more weight to the last information Memory decay Failure to document job performance throughout appraisal period 7 Contrast effects If a criterion is notclear or a ranking system is used contrast effects will occur How to avoid appraisal problems Training the raters Developing appraisal criteria from documented job analysis Choosing the right appraisal tools BARS for service industry Increasing times of appraisal formal and informal Inviting subordinate participation Diary-keepingThe Appraisal Interview Types of interview TYPE Performance is satisfactory----employee is promotable satisfactory---- Not promotable Unsatisfactory----correctable OBJECTIVE Make development plans Maintain performance Plan correction Principle of interview Assembling the data Informing the employee at least one week earlier Enough time during the interview A quiet but not closed room Let employee relaxed Encourage the person to talk Help employee to improve his performance Dont get personal Be specific and direct Get agreement on how things will be improved and by when Process ofPerformance Management 案例一摩托罗拉绩效管理企业产品服务企业管理人力资源管理人力资源管理绩效管理摩托罗拉给绩效管理下的定义是绩效管理是一个不断进行的沟通过程案例一摩托罗拉绩效管理沟通内容 1 员工应该完成的工作2员工所做的工作如何为组织的目标实现做贡献3用具体的内容描述怎样才算把工作做好4员工和主管怎样才能共同努力帮助员工改进绩效5 如何衡量绩效6确定影响绩效的障碍并将其克服案例一摩托罗拉绩效管理一绩效计划在这个部分里主管与员工就下列问题达成一致1 员工应该做什么2 工作应该做多好3 为什么要做该项工作4 什么时候要做该项工作5 其他相关的问题环境能力职业前途培训等绩效目标业务目标business goals行为标准behavior standard 案例一摩托罗拉绩效管理二持续不断的绩效沟通强调全年的沟通和全通道的沟通 1 沟通是一个双向的过程目的是追踪绩效的进展确定障碍为双方提供所需信息2防止问题的出现或及时解决问题前瞻性 3定期或非定期正式或非正式就某一问题专门对话 4在这个过程中也要形成必要的文字记录必要时经主管和员工双方签字认可案例一摩托罗拉绩效管理三事实的收集观察和记录 1收集与绩效有关的资讯2记录好的以及不好的行为收集资讯全面好的不好的都要记录而且要形成书面文件必要的要经主管与员工签字认可以上两个过程一般在二三季度完成进入四季度也就进入了绩效管理的收关阶段到了检验一年绩效的时候了案例一摩托罗拉绩效管理四绩效评估会议摩托罗拉的绩效评估会议是非常讲究效率的一般集中一个时间所有的主管集中在一起进行全年的绩效评估它主要包括以下四个方面1做好准备工作员工自我评估2对员工的绩效达成共识根据事实而不是印象3评出绩效的级别4不仅是评估员工而且是解决问题的机会最终形成书面的讨论结果并以面谈沟通的形式告知员工考核结束不是说绩效管理就到此为止还有一个非常重要的诊断过程案例一摩托罗拉绩效管理五绩效诊断和提高这个过程是用来诊断绩效管理系统的有效性用来改进和提高员工绩效主要包括以下四个方面1确定绩效缺陷及原因2通过指导解决问题3绩效不只是员工的责任4应该不断进行 10个方面的工具衡量1我有针对我工作的具体明确的目标2这些目标具有挑战性但合理不太难也不太容易3我认为这些目标它对我有意义4我明白我的绩效达到目标是如何评估的5我觉得那些绩效标准是恰当的因为它们测量的是我应该做的事情6在达到目标方面我做的如何我能得到及时的反馈7我觉得我得到足够的培训使我能得到及时准确的反馈8公司给我提供了足够的资源例如钱仪器帮手等使我达到目标成为可能9当我达到目标时我得到赞赏和认可10奖励体系是公平的我因为自己的成功而得到奖励案例二罗芸与老马的绩效考核分歧飞宴航空食品公司服务于航空公司和其他订购盒饭和西餐的单位雇佣厨房人员采购全部原料提供给客户不搞分包制罗芸ＭＢＡ毕业公司总部四年的职能性管理工作担任飞宴航空食品公司地区经理近一年负责管理１０家供应站点每站有一个主任负责一定范围内的客户销售和服务老马供应站主任主任主要负责计划编制预算监控分管指定客户的销售服务员等活动资格最老只念过一年大专从厨房代班长干起三年前上任善于搞关系铁杆客户没有流失的客户部下经指点和培养得到提升作其他地区的经理但是不良饮食带来了健康问题请假３个月给罗打电话的次数超过了其他９位的总数好邀功案例二罗芸与老马的绩效考核分歧机会罗芸需要副手一名即地区副经理老马公开说他资格最老业绩好非他莫属罗芸觉得两人的管理风格太悬殊老马的行为会激怒地区和公司的工作人员绩效考评１０分制１０分为最优７－９良好５－６合格中等３－４较差１－２最差结果虽然老马一年的工作不错但是罗给了６分理由不注意卫生病假３个月案例二罗芸与老马的绩效考核分歧思考１罗对老马的绩效考评是否合理需要改进的地方２预计老马的反应如何罗怎样处理３如果你是老马对罗的结果采取怎样的态度和做法为什么案例二罗芸与老马的绩效考核分歧启示完整的绩效管理过程包括绩效计划绩效沟通绩效考核和绩效反馈四个方面１绩效计划绩效管理的起点上级和员工共同讨论达成一致２绩效沟通上下沟通预防或解决实现绩效可能发生的问题３绩效考核确定主题和方法作出评价４绩效反馈绩效周期结束上下级的绩效面谈告诉结果和不足一起制定改进计划案例中没有共同绩效计划缺乏全面评价的根据没有绩效沟通主观地考核不能公正公平和合理 Strengths Combine the benefits of critical incidents and quantitative rating Useful for directing and monitoring behavior Weaknesses Research has not substantiated its superiority over other methods Choosing one indicative behavior Time consuming to develop Behaviorally Anchored Rating Scales Goal Setting Planning Evaluation Management-By-Objectives Strengths Directing and monitoring behavior Performance standards are objective Practical and inexpensive Employee participation Weaknesses Does notspecify behaviors Focus on short-term Factors outside workers control Standards vary User acceptance Management-By-Objectives Financial indexes 1970s 1980s Product quality 1990s Satisfactory of customers Recent Balanced score card on managerial and competitive ability 指标构成核心构想财务衡量指标非财务衡量指标顾客满意度企业必须通过创新与学习持续改善企业内部运作过程获得最大化的客户满意才能获得不凡的财务收益罗伯特·S ·卡普兰和大卫· P ·诺顿内部流程创新与学习平衡记分卡是哈佛大学财会学教授罗伯特·S ·卡普兰和复兴方案公司总裁大卫· P ·诺顿在积累了大量实践经验的基础上建立的一套革命性管理系统目标考量财务面我们在股东眼里的表现目标考量客户面我们在客户眼里的表现目标考量内部运营面什么是关键成功因素什么业务流程是最优目标考量学习与成长面我们能保持创新变化和不断提高使命和策略飞行高度飞行速度耗油量以收益为基础的财务数字仅能够衡量过去决策的结果却无法评估未来的绩效表现容易误导企业未来发展方向当财务指标为企业绩效评估的唯一指标时容易使经营者过分注重短期财务结果急功近利有强烈动机操纵报表上的数字而不愿就企业长期策略目标进行资本投资由于不重视非财务性指标的评估致使企业竞争力下降原本强劲的财务数字有可能逐渐恶化财务性数据发生的根本原因不做深入的分析和调查片面的指标收集难以推动整体绩效的改善客户面内部流程财务性指标非财务性指标销售收入利润总额资金回笼现金流量成本支出全自动双缸单缸 xxxxxxxx xxxx xxx xxxxx xxxx xxx xxxxx xxxx 学习与成长面以公司竞争战略为出发点全面动态地评估有效防止次优化行为提出具体的改进目标对信息系统的灵敏性要求高对企业管理基础的要求比较高优点缺点罗克沃特公司是一家全球性的工程建筑公司的全资资公司在水下工程建筑业中处于全球领先地位高级管理团队把公司的愿景和战略转化为平衡计分卡愿景作为受顾客欢迎的供货商我们应成为行业领导者战略提供需要的服务顾客满意持续改进员工素质提高股东预期实现资本报酬率现金流项目盈利性业绩可靠性财务层面客户层面内部层面学习成长金钱的价值竞争性价格无争吵的关系表现优异的专业人员创新塑造顾客需要中标率品质服务安全损失控制良好的项目管理持续改进产品和服务创新得到授权的员工罗克沃特的战略目标 Human Resource Management 资本报酬率现金流项目盈利性利润预测可靠性销售储备财务层面客户层面内部层面创新与学习价格指数顾客排名调查顾客满意度指数市场份额与顾客讨论新工作的小时数投标成功率返工安全事件指数项目业绩指数项目终止周期新服务收入所占比例提高指数员工态度调查员工合理化建议数员工人均收益罗克沃特的平衡计分卡评估 Human Resource Management Causesof Halo Effect Highest lowest Highest lowest Causes of Leniency strictness Errors 1 2 3 4 5 Causes of Central Tendency Error 1 2 3 45 Stereotyping 1 23 4 5Similarity Causes of primacy bias Causes of Recency Error 1 2 3 45 P167 KPI Appraisal method Process of appraisal Appraisal interview Compensation Training Development Raters training Organizational strategy Results What Behavior How Performance Behaviors and results of jobs related to the organizational goals Quantity CostFinancial Quality Timing Behavior 合格率错误率投诉支出费用总额实际费用和预算的对比增长率利润率生产率产品数量处理零件的数量接听电话会见客户销售额利润限期胜任特征关键行为 P FSOME Skill Motivation Environment Opportunity Performance Factors influencing performance External Factors Internal Factors 绩效管理 1 控制方式事前事中及事后 2 沟通方式自上而下和自下而上结合反馈充足 3 公司各个部门都是绩效管理主体全员参加 4 薪酬福利晋升培训等人力资源相关领域u 行政使用 l 补偿 l 晋升 l 解雇 l 降职 l 临时解雇开发使用 l 识别优势 l 识别成长领域 l 开发计划 l 培训和职业生涯计划绩效管理 Strategic Plan Effective Performance Appraisal System Direct Behavior Correct Behavior Monitor Behavior Input Into Employment Decisions Perceived Fair And Accurate Process Improved Job Performance Improved Employment Decisions Minimized Litigation And Job Dissatisfaction Competitive Advantage Importance of Performance appraisal Supervisors Employee Subordinates Customers Self-rating Outside observers Peer 360 Degree Feedback 360 Degree Feedback systems are used most often as feedback devices Companies considering the use of 360-degree ratings for evaluative purposes shouldproceed cautiously --Appraised by the immediate supervisor--Self-ratings--Using peer appraisals--Appraised by customers--Appraised by subordinates--Rating committees Basic Appraisal Methods 1 Mike Winkle 2 Robert King3 Sally Morris4 Fred Taft Mike Robert Sally Fred MikeRobert Sally Fred Alternation Ranking Paired Comparison A B C D E 5 15 70 Forced Distribution EX --Exceptional WD --With distinction HS-- High standard RI --Room for improvement NA --unacceptable Employee Comparison Systems Ranking Methods Unsatisfactory Satisfactory Outstanding Quantity of work Qualityof work Dependability Graphic Rating Scale P160 Traits and a range of Performance Strengths Low cost Practical Single form applicable to all or most jobs in organization Weaknesses Accuracy questionable Fail to direct behavior Nonspecific job performance feedback Graphic Rating Scale P160 almost neveralmost always 1 2 3 4 5 ___1 Sets clear priorities for multiple goals ___2 Coaches subordinates effectively ___3 Breaks projects into doable components ___4 Develops subordinatesknowledge and skills ___5 Listens to employees concerns ___6 Seeksdecision input from subordinates Behavioral Observation Scale---Critical incident method Strengths Useful for directing and monitoringbehavior Useful for providing specific feedback WeaknessesTime-consuming to develop Behavioral Observation Scales EffectiveIneffective Group member has read all agreed-upon material Group memberparticipates in discussions though not always prepared Group member doeslittle work and offers no valuable ideas or feedback 5 4 3 2 1 Qualityof Group Member Input Behaviorally anchored rating scales BARS。

3gpp协议

3gpp协议

3GPP TR 36.942 V9.0.1(2010-04)Technical Report3rd Generation Partnership Project;Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA);Radio Frequency (RF) system scenarios(Release 9)The present document has been developed within the 3rd Generation Partnership Project (3GPP TM ) and may be further elaborated for the purposes of 3GPP.The present document has not been subject to any approval process by the 3GPP Organizational Partners and shall not be implemented.This Specification is provided for future development work within 3GPP only. The Organizational Partners accept no liability for any use of this Specification. Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organizational Partners' Publications Offices.KeywordsLTE, Radio3GPPPostal address3GPP support office address650 Route des Lucioles - Sophia AntipolisValbonne - FRANCETel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16InternetCopyright NotificationNo part may be reproduced except as authorized by written permission.The copyright and the foregoing restriction extend to reproduction in all media.© 2010, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC).All rights reserved.UMTS™ is a Trade Mark of ETSI registered for the benefit of its members3GPP™ is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational PartnersLTE™ is a Trade Mark of ETSI currently being registered for the benefit of i ts Members and of the 3GPP Organizational Partners GSM® and the GSM logo are registered and owned by the GSM AssociationContentsForeword (6)1Scope (7)2References (7)3Definitions, symbols and abbreviations (8)3.1Definitions (8)3.2Symbols (8)3.3Abbreviations (8)4General assumptions (9)4.1Interference scenarios (10)4.2Antenna Models (10)4.2.1BS antennas (10)4.2.1.1BS antenna radiation pattern (11)4.2.1.2BS antenna heights and antenna gains for macro cells (11)4.2.2UE antennas (12)4.2.3MIMO antenna Characteristics (12)4.3Cell definitions (12)4.4Cell layouts (12)4.4.1Single operator cell layouts (12)4.4.1.1Macro cellular deployment (12)4.4.2Multi operator / Multi layer cell layouts (12)4.4.2.1Uncoordinated macro cellular deployment (13)4.4.2.2Coordinated macro cellular deployment (13)4.5Propagation conditions and channel models (14)4.5.1Received signal (14)4.5.2Macro cell propagation model – Urban Area (14)4.5.3Macro cell propagation model – Rural Area (15)4.6Base-station model (15)4.7UE model (17)4.8RRM models (18)4.8.1Measurement models (18)4.8.2Modelling of the functions (18)4.9Link level simulation assumptions (18)4.10System simulation assumptions (18)4.10.1System loading (18)5Methodology description (18)5.1Methodology for co-existence simulations (18)5.1.1Simulation assumptions for co-existence simulations (18)5.1.1.1Scheduler (18)5.1.1.2Simulated services (19)5.1.1.3ACIR value and granularity (19)5.1.1.4.1Uplink Asymmetrical Bandwidths ACIR (Aggressor with larger bandwidth) (19)5.1.1.4.2Uplink Asymmetrical Bandwidths ACIR (Aggressor with smaller bandwidth) (22)5.1.1.4Frequency re-use and interference mitigation schemes for E-UTRA (22)5.1.1.5CQI estimation (23)5.1.1.6Power control modelling for E-UTRA and 3.84 Mcps TDD UTRA (23)5.1.1.7SIR target requirements for simulated services (23)5.1.1.8Number of required snapshots (23)5.1.1.9Simulation output (23)5.1.2Simulation description (24)5.1.2.1Downlink E-UTRA interferer UTRA victim (24)5.1.2.2Downlink E-UTRA interferer E-UTRA victim (24)5.1.1.1Uplink E-UTRA interferer UTRA victim (24)5.1.2.4Uplink E-UTRA interferer E-UTRA victim (25)6System scenarios (25)6.1Co-existence scenarios (26)7Results (26)7.1Radio reception and transmission (26)7.1.1FDD coexistence simulation results (26)7.1.1.1ACIR downlink 5MHz E-UTRA interferer – UTRA victim (26)7.1.1.2ACIR downlink 10MHz E-UTRA interferer – 10MHz E-UTRA victim (27)7.1.1.3ACIR uplink 5MHz E-UTRA interferer – UTRA victim (29)7.1.1.4ACIR uplink 10MHz E-UTRA interferer – 10MHz E-UTRA victim (31)7.1.2TDD coexistence simulation results (34)7.1.2.1ACIR downlink 5MHz E-UTRA interferer – UTRA 3.84 Mcps TDD victim (34)7.1.2.2ACIR downlink 10MHz E-UTRA interferer – 10MHz E-UTRA TDD victim (36)7.1.2.3ACIR downlink 1.6 MHz E-UTRA interferer – UTRA 1.28 Mcps TDD victim (38)7.1.2.4ACIR uplink 5MHz E-UTRA interferer – UTRA 3.84 Mcps TDD victim (41)7.1.2.5ACIR uplink 10MHz E-UTRA interferer – 10MHz E-UTRA TDD victim (43)7.1.2.6ACIR uplink 10MHz E-UTRA interferer – 10MHz E-UTRA TDD victim (LCR frame structurebased) (45)7.1.2.7ACIR downlink 10MHz E-UTRA interferer – 10MHz E-UTRA TDD victim (LCR framestructure based) (46)7.1.3Additional coexistence simulation results (48)7.1.3.1ACIR downlink E-UTRA interferer – GSM victim (48)7.1.3.2ACIR uplink E-UTRA interferer – GSM victim (50)7.1.3.3Asymmetric coexistence 20 MHz and 5 MHz E-UTRA (51)7.1.3.4Impact of cell range and simulation frequency on ACIR (53)7.1.3.5Uplink Asymmetric coexistence TDD E-UTRA to TDD E-UTRA (54)7.1.4Base station blocking simulation results (56)7.2RRM (58)8Rationales for co-existence requirements (58)8.1BS and UE ACLR (58)8.1.1Requirements for E-UTRA – UTRA co-existence (58)8.1.2Requirements for E-UTRA – E-UTRA co-existence (59)9Deployment aspects (59)9.1UE power distribution (59)9.1.1Simulation results (60)10Multi-carrier BS requirements (62)10.1Unwanted emission requirements for multi-carrier BS (62)10.1.1General (62)10.1.2Multi-carrier BS of different E-UTRA channel bandwidths (63)10.1.3Multi-carrier BS of E-UTRA and UTRA (63)10.2Receiver requirements for multi-carrier BS (64)10.2.1General (64)10.2.2Test principles for a multi-carrier BS of equal or different E-UTRA channel bandwidths (65)11Rationale for unwanted emission specifications (65)11.1Out of band Emissions (65)11.1.1Operating band unwanted emission requirements for E-UTRA BS (spectrum emission mask) (65)11.1.2ACLR requirements for E-UTRA BS (67)11.2Spurious emissions (69)11.2.1BS Spurious emissions (69)11.2.2General spurious emissions requirements for E-UTRA BS (69)11.2.3Specification of BS Spurious emissions outside the operating band (70)11.2.4Additional spurious emissions requirements (71)Annex A (informative): Link Level Performance Model (71)A.1Description (71)A.2Modelling of Link Adaptation (73)A.3UTRA 3.84 Mcps TDD HSDPA Link Level Performance (75)A.4Link Level Performance for E-UTRA TDD (LCR TDD frame structure based) (76)Annex B (informative): Smart Antenna Model for UTRA 1.28 Mcps TDD (79)B.1Description (79)Annex C (informative): Change history (83)ForewordThis Technical Report has been produced by the 3rd Generation Partnership Project (3GPP).The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows:Version x.y.zwhere:x the first digit:1 presented to TSG for information;2 presented to TSG for approval;3 or greater indicates TSG approved document under change control.y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc.z the third digit is incremented when editorial only changes have been incorporated in the document.1 ScopeDuring the E-UTRA standards development, the physical layer parameters will be decided using system scenarios, together with implementation issues, reflecting the environments that E-UTRA will be designed to operate in.2 ReferencesThe following documents contain provisions which, through reference in this text, constitute provisions of the present document.•References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.•For a specific reference, subsequent revisions do not apply.•For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (includinga GSM document), a non-specific reference implicitly refers to the latest version of that document in the sameRelease as the present document.[1] 3GPP TR 25.896, “Feasibility Study for Enhanced Uplink for UTRA FDD”[2] 3GPP TR 25.816, “UMTS 900 MHz Work Item Technical Report”[3] 3GPP TR 25.942, “Radio Frequency (RF) system scenarios”[4] 3GPP TR 25.814, “Physical Layer Aspects for Evolved UTRA”[5] 3GPP TR 30.03, “Selection procedures for the choice of radio transmission technologies of theUMTS”[6] R4-051146, “Some operators’ requirements for prioritization of performance requirements work inRAN WG4”, RAN4#37[7] 3GPP TR 25.951, “FDD Base Station (BS) classification”[8] 3GPP TR 25.895, ”Analysis of higher chip rates for UTRA TDD evolution.”[9] R4-070235, “Analysis of co-existence simulation results”, RAN4#42[10] R4-070084, “Coexistence Simulation Results for 5MHz E-UTRA -> UTRA FDD Uplink withRevised Simulation Assumptions”, RAN4#42[11] R4-070034, “Additional simulation results on 5 MHz LTE to WCDMA FDD UL co-existencestudies”, RAN4#42[12] R4-070262, “Simulation results on 5 MHz LTE to WCDMA FDD UL co-existence studies withrevised simulation assumptions”, RAN4#42[13] R4-070263, “Proposal on LTE ACLR requirements for UE”, RAN4#42[14] R4-061288, “Downlink LTE 900 (Rural Macro) with Downlink GSM900 (Rural Macro) Co-existence Simulation Results”, RAN4#41[15] R4-070391, “LTE 900 - GSM 900 Downlink Coexistence”, RAN4#42bis[16] R4-061304, “LTE 900 - GSM 900 Uplink Simulation Results”, RAN4#41[17] R4-070390, “LTE 900 - GSM 900 Uplink Simulation Results”, RAN4#42bis[18] R4-070392 “LTE-LTE Coexistence with asymmetrical bandwidth”, RAN4#42bis[19] 3GPP TS 36.104, ”Base Station (BS) radio transmission and reception”[20] 3GPP TS 25.104, ”Base Station (BS) radio transmission and reception (FDD)”[21] 3GPP TS 36.141, ”Base Station (BS) conformance testing”[22] Recommendation ITU-R SM.329-10, “Unwanted emissions in the spurious domain”[23] “International Telecommunications Union Radio Regulations”, Edition 2004, Volume 1 – Articles,ITU, December 2004.[24] “Adjacent Band Compatibility between UMTS and Other Services in the 2 GHz Band”, ERCReport 65, Menton, May 1999, revised in Helsinki, November 1999.[25] “Title 47 of the Code of Federal Regulations (CFR)”, Federal Communications Commission.[26] R4-070337, "Impact of second adjacent channel ACLR/ACS on ACIR" (Nokia SiemensNetworks).[27] R4-070430, "UE ACS and BS ACLRs" (Fujitsu ).[28] R4-070264, "Proposal on LTE ACLR requirements for Node B" (NTT DoCoMo).[29] Recommendation ITU-R M.1580-1, “Generic unwanted emission characteristics of base stationsusing the terrestrial radio interfaces of IMT-2000”.[30] Report ITU-R M.2039, “Characteristics of terrestrial IMT-2000 systems for frequencysharing/interference analyses”.[31] E TSI EN 301 908-3 V2.2.1 (2003-10), “Electromagnetic compatibility and Radio spectrumMatters (ERM); Base Stations (BS), Repeaters and User Equipment (UE) for IMT-2000 Third-Generation cellular networks; Part 3: Harmonized EN for IMT-2000, CDMA Direct Spread(UTRA FDD) (BS) covering essential requirements of article 3.2 of the R&TTE Directive”.3 Definitions, symbols and abbreviations3.1 Definitions3.2 Symbols3.3 AbbreviationsFor the purposes of the present document, the following abbreviations apply:ACIR Adjacent Channel Interference RatioACLR Adjacent Channel Leakage power RatioACS Adjacent Channel SelectivityAMC Adaptive Modulation and CodingAWGN Additive White Gaussian NoiseBS Base StationCDF Cumulative Distribution FunctionDL DownlinkFDD Frequency Division DuplexMC Monte-CarloMCL Minimum Coupling LossMCS Modulation and Coding SchemePC Power ControlPSD Power Spectral DensityRX ReceiverTDD Time Division DuplexTX TransmitterUE User EquipmentUL Uplink4 General assumptionsThe present document discusses system scenarios for E-UTRA operation primarily with respect to the radio transmission and reception including the RRM aspects. To develop the E-UTRA standard, all the relevant scenarios need to be considered for the various aspects of operation and the most critical cases identified. The process may then be iterated to arrive at final parameters that meet both service and implementation requirements.The E-UTRA system is intended to be operated in the same frequency bands specified for UTRA. In order to limit the number of frequency bands to be simulated in the various simulation scenarios a mapping of frequency bands to two simulation frequencies (900 MHz and 2000 MHz) is applied. When using the macro cell propagation model ofTR25.942 [3], the frequency contributes to the path loss by 21*log10(f). The maximum path loss difference between the lowest/highest frequencies per E-UTRA frequency band and corresponding simulation frequency is shown in tables 4.1 and 4.2.Table 4.1: Simulation frequencies for FDD mode E-UTRA frequency bandsTable 4.2: Simulation frequencies for TDD mode E-UTRA frequency bandsIt can be observed that the difference of path loss between simulation frequency and operating frequency (except bands 7, 11 and 38) is in the worst case less than 0.8 dB for the downlink and less the 1,5 dB for the uplink. Hence the mapping of operating frequency to simulation frequency will provide valid results.The validity of simulations performed at 2 GHz for the 2.6 GHz bands 7 and 38 was already analyzed in TR 25.810. Considering the expected higher antenna gain in the 2.6 GHz band the difference in path loss is in the order of 1 dB what is comparable to the other frequency bands.4.1 Interference scenariosThis chapter should cover how the interference scenarios could occur e.g. BS-BS, UE-BS etc.4.2 Antenna ModelsThis chapter contains the various antenna models for BS and UE4.2.1 BS antennas4.2.1.1 BS antenna radiation patternThe BS antenna radiation pattern to be used for each sector in 3-sector cell sites is plotted in Figure 4.1. The pattern is identical to those defined in [1], [2] and [4]:()23min 12, where 180180m dB A A θθθθ⎡⎤⎛⎫⎢⎥=--≤≤ ⎪⎢⎥⎝⎭⎣⎦,dB 3θ is the 3dB beam width which corresponds to 65 degrees, and dB A m 20= is the maximum attenuationFigure 4.1: Antenna Pattern for 3-Sector Cells4.2.1.2 BS antenna heights and antenna gains for macro cellsAntenna heights and gains for macro cells are given in table 4.3.Table 4.3: Antenna height and gain for Macro Cells4.2.2 UE antennasFor UE antennas, a omni-directional radiation pattern with antenna gain 0dBi is assumed [2], [3], [4].4.2.3 MIMO antenna Characteristicsxxxx4.3 Cell definitionsThis chapter contain the cell properties e.g. cell range, cell type (omni, sector), MIMO cell definitions etc.4.4 Cell layoutsThis chapter contains different cell layouts in form of e.g. single operator, multi-operator and multi layer cell layouts(e.g. macro-micro etc).4.4.1 Single operator cell layouts4.4.1.1 Macro cellular deploymentBase stations with 3 sectors per site are placed on a hexagonal grid with distance of 3*R, where R is the cell radius (see Figure 4.2), with wrap around. The number of sites shall be equal to or higher than 19. [2] [4].Figure 4.2: Single operator cell layout4.4.2 Multi operator / Multi layer cell layouts4.4.2.1 Uncoordinated macro cellular deploymentFor uncoordinated network simulations, identical cell layouts for each network shall be applied, with worst case shift between sites. Second network’s sites are located at the first network’s cell edge, as shown in Figure 4.3 [2].Figure 4.3: Multi operator cell layout - uncoordinated operation4.4.2.2 Coordinated macro cellular deploymentFor coordinated network simulations, co-location of sites is assumed; hence identical cell layouts for each network shall be applied [2].Figure 4.4: Multi operator cell layout - coordinated operation4.5 Propagation conditions and channel modelsThis chapter contains the definition of channel models, propagation conditions for various environments e.g. urban, suburban etc.For each environment a propagation model is used to evaluate the propagation pathloss due to the distance. Propagation models are adopted from [3] and [4] and presented in the following clauses.4.5.1 Received signalAn important parameter to be defined is the minimum coupling loss (MCL). MCL is the parameter describing the minimum loss in signal between BS and UE or UE and UE in the worst case and is defined as the minimum distance loss including antenna gains measured between antenna connectors. MCL values are adopted from [3] and [7] as follows:Table 4.4: Minimum Coupling LossesWith the above definition, the received power in downlink and uplink can be expressed as [3]: RX_PWR = TX_PWR – Max (pathloss – G_TX – G_RX, MCL) where:RX_PWR is the received signal power TX_PWR is the transmitted signal power G_TX is the transmitter antenna gain G_RX is the receiver antenna gain4.5.2 Macro cell propagation model – Urban AreaMacro cell propagation model for urban area is applicable for scenarios in urban and suburban areas outside the high rise core where the buildings are of nearly uniform height [3]:80dB (f)log 21(Dhb)log 18(R)log Dhb)104(140L 1010103+⋅+⋅-⋅⋅⋅-⋅=-where:R is the base station-UE separation in kilometres f is the carrier frequency in MHzDhb is the base station antenna height in metres, measured from the average rooftop levelConsidering a carrier frequency of 900MHz and a base station antenna height of 15 metres above average rooftop level, the propagation model is given by the following formula [4]:(R)37,6log 120,9L 10+=where:R is the base station-UE separation in kilometresConsidering a carrier frequency of 2000MHz and a base station antenna height of 15 metres above average rooftop level, the propagation model is given by the following formula:(R)37,6log 128,1L 10+=where:R is the base station-UE separation in kilometresAfter L is calculated, log-normally distributed shadowing (LogF) with standard deviation of 10dB should be added [2], [3]. A Shadowing correlation factor of 0.5 for the shadowing between sites (regardless aggressing or victim system) and of 1 between sectors of the same site shall be used The pathloss is given by the following formula:LogF L acro Pathloss_m +=NOTE 1: L shall in no circumstances be less than free space loss. This model is valid for NLOS case only anddescribes worse case propagation NOTE 2: The pathloss model is valid for a range of Dhb from 0 to 50 metres.NOTE 3: This model is designed mainly for distance from few hundred meters to kilometres. This model is notvery accurate for short distances. NOTE 4: The mean building height is equal to the sum of mobile antenna height (1,5m) and 10,5m Δh m = [5]. NOTE 5: Some downlink simulations in this TR were performed without shadowing correlation, however it wasreported this has a negligible impact on the simulation results.4.5.3 Macro cell propagation model – Rural AreaFor rural area, the Hata model was used in the work item UMTS900[2], this model can be reused:L (R)= 69.55 +26.16log 10(f)–13.82log 10(Hb)+[44.9-6.55log 10(Hb)]log(R) – 4.78(Log 10 (f))2+18.33 log 10 (f) -40.94 where:R is the base station-UE separation in kilometres f is the carrier frequency in MHzHb is the base station antenna height above ground in metresConsidering a carrier frequency of 900MHz and a base station antenna height of 45 meters above ground the propagation model is given by the following formula:(R)34,1log 5,95L 10+=where:R is the base station-UE separation in kilometresAfter L is calculated, log-normally distributed shadowing (LogF) with standard deviation of 10dB should be added [2], [3]. A Shadowing correlation factor of 0.5 for the shadowing between sites (regardless aggressing or victim system) and of 1 between sectors of the same site shall be used. The pathloss is given by the following formula:LogF L acro Pathloss_m +=NOTE 1: L shall in no circumstances be less than free space loss. This model is valid for NLOS case only anddescribes worse case propagation NOTE 2: This model is designed mainly for distance from few hundred meters to kilometres. This model is notvery accurate for short distances.4.6 Base-station modelThis chapter covers the fundamental BS properties e.g. output power, dynamic range, noise floor etc.Reference UTRA FDD base station parameters are given in Table 4.5.Table 4.5: UTRA FDD reference base station parameters（wcdma）Reference base station parameters for UTRA 1.28Mcps TDD are given in Table 4.5a.Table 4.5a: Reference base station for UTRA 1.28Mcps TDD（td-scdma）Reference UTRA 3.84 Mcps TDD base station parameters are given in Table 4.5b.Table 4.5b: Reference base station for UTRA 3.84Mcps TDD（td-cdma）Reference E-UTRA FDD and E-UTRA TDD base station parameters are given in Table 4.6.Table 4.6: E-UTRA FDD and E-UTRA TDD reference base station parametersReference base station parameters for E-UTRA TDD (LCR TDD frame structure based) are given in Table 4.6a.Table 4.6a: Reference base station for E-UTRA TDD (LCR TDD frame structure based)（td-lte）4.7 UE modelThis chapter covers the fundamental UE properties e.g. output power, dynamic range, noise floor etc. Reference UTRA FDD parameters are given in Table 4.7.Table 4.7: UTRA FDD reference UE parametersfor simulation alignment purpose, a Noise Figure of 9 dB will be used.Reference UTRA 1.28 Mcps TDD parameters are given in Table 4.7aTable 4.7a: Reference UE for UTRA 1.28 Mcps TDDReference UTRA 3.84 Mcps TDD UE parameters are given in Table 4.7b.Table 4.7b: UTRA 3.84 Mcps TDD reference UE parametersfor simulation alignment purpose, a Noise Figure of 9 dB will be used.Reference E-UTRA FDD and E-UTRA TDD UE parameters are given in Table 4.8.Table 4.8: E-UTRA FDD and E-UTRA TDD reference UE parametersHowever, for simulation alignment purpose, a Noise Figure of 9 dB will be used. Reference E-UTRA TDD UE (LCR TDD frame structure based) parameters are given in Table 4.8a.Table 4.8a: Reference UE for EUTRA TDD (LCR TDD frame structure based)4.8 RRM modelsThis chapter contains models that are necessary to study the RRM aspects e.g.4.8.1 Measurement modelsxxxx4.8.2 Modelling of the functionsxxxx4.9 Link level simulation assumptionsThis chapter covers Layer 1 aspects and assumptions (e.g. number of HARQ retransmissions) etc.4.10 System simulation assumptionsThis chapter contains system simulation assumptions e.g. Eb/No values for different services, activity factor for voice, power control steps, performance measures (system throughput, grade of service), confidence interval etc.4.10.1 System loadingxxxx5 Methodology descriptionThis chapter describes the methods used for various study items e.g. deterministic analysis for BS-BS interference, Monte-Carlo simulations and dynamic type of simulations for RRM.5.1 Methodology for co-existence simulationsSimulations to investigate the mutual interference impact of E-UTRA, UTRA and GERAN are based on snapshots were users are randomly placed in a predefined deployment scenario (Monte-Carlo approach). Assumptions or E-UTRA in this chapter are based on the physical layer (OFDMA DL and SC-FDMA UL) as described in the E-UTRA study item report [4]. It must be noted that actual E-UTRA physical layer specification of frequency resource block is different regarding number ofsub-carriers per resource block (12 instead of 25 specified in [4]) and regarding the size of a resource block (180 kHz instead of 375 kHz in [4]). However, this has no impact on the results and conclusions of the present document.5.1.1 Simulation assumptions for co-existence simulations5.1.1.1 SchedulerFor initial E-UTRA coexistence simulations Round Robin scheduler shall be used.5.1.1.2 Simulated servicesWhen using Round Robin scheduler, full buffer traffic shall be simulated. For E-UTRA downlink, one frequency resource block for one user shall be used. The E-UTRA system shall be maximum loaded, i.e. 24 frequency resource blocks in 10 MHz bandwidth and 12 frequency resource blocks in 5 MHz bandwidth respectively. For E-UTRA uplink, the number of allocated frequency resource blocks for one user is 4 for 5 MHz bandwidth and 8 for 10 MHz bandwidth respectively.For the 5 MHz TDD UTRA victim using 3.84 Mcps TDD, Enhanced Uplink providing data service shall be used where 1 UE shall occupy 1 Resource Unit (code x timeslot). Here the number of UE per timeslot is set to 3 UEs/timeslot.Other services, e.g. constant bit rate services are FFS.5.1.1.3 ACIR value and granularityFor downlink a common ACIR for all frequency resource blocks to calculate inter-system shall be used. Frequency resource block specific ACIR is FFS.For uplink it is assumed that the ACIR is dominated by the UE ACLR. The ACLR model is described in table 5.1 and table 5.2Table 5.1: ACLR model for 5MHz E-UTRA interferer and UTRAvictim, 4 RBs per UETable 5.2: ACLR model for E-UTRA interferer and 10MHz E-UTRA victimNote: This ACLR models are agreed for the purpose of co-existence simulations. ACLR/ACS requirements need to be discussedseparately.5.1.1.4.1 Uplink Asymmetrical Bandwidths ACIR (Aggressor withlarger bandwidth)Since the uplink ACLR of the aggressor is measured in the aggressor’s bandwidth, for uplink asymmetrical bandwidth coexistence, a victim UE with a smaller bandwidth than that of the aggressor will receive a fraction of the interference power caused by the aggressor’s ACLR. For two victim UEs falling within the 1st ACLR of the aggressor, the victim UE closer in frequency to the aggressor will experience higher interference than one that is further away in frequency. The difference in interference depends on the power spectral density (PSD) within the aggressor’s 1st ACLR bandwidth. For simplicity, it is assumed that the PSD is flat across the aggressor’s ACLR bandwidth. Hence, the ACLR can be relaxed (or increased) by the factor, F ACLR:F ACLR = 10 × LOG10(B Aggressor/B Victim)Where, B Aggressor and B Victim are the E-UTRA aggressor and victim bandwidths respectively.20 MHz E-UTRA 5 MHz E-UTRAFigure 5.1: 20 MHz E-UTRA UE aggressor to 5 MHz E-UTRA UEvictims20 MHz E-UTRA 10 MHz E-UTRAFigure 5.2: 20 MHz E-UTRA UE aggressor to 10 MHz E-UTRAUE victimsIn Table 5.2, the aggressor UE that is non adjacent to the victim UE, the victim UE will experience an interference due to an ACLR of 43 + X –F ACLR. For the case where the aggressor UE is adjacent to the victim UEs, consider the scenarios in Figure 5.1, 5.2 and 5.3, where a 20 MHz E-UTRA aggressor is adjacent to 3 victim UEs of 5 MHz, 10 MHz and 15 MHz E-UTRA systems respectively.In Figure 5.1, all the UEs in the 5 MHz E-UTRA system will be affected by an ACLR of 30 + X - F ACLR. For the 10 MHz E-UTRA victims in Figure 5.2, two UEs will be affected by an ACLR of 30 + X - F ACLR whilst 1 UE will be affected by a less severe ACLR of 43 + X- F ACLR . In the 15 MHz E-UTRA victim as shown in Figure 5.3, the UE next to the band edge will be affected by an ACLR of 30 + X - F ACLR whilst the UE farthest from the band edge will be affected by an ACLR of 43 + X - F ACLR. The victim UE of the 15 MHz E-UTRA occupying the centre RB (2nd from band edge) is affected by 1/3 ACLR of 30 + X - F ACLR and 2/3 ACLR of 43 + X - F ACLR. This gives an ACLR of 34 + X - F ACLR.Using a similar approach for 15 MHz, 10 MHz and 5 MHz aggressor with a victim of smaller system bandwidth, the ACLR affecting each of the 3 victim UEs can be determined. This is summarised in Table 5.2A. Here the value Y is defined for victim UE, where ACLR = Y + X - F ACLR. UE1 is the UE adjacent to the aggressor, UE2 is located at the centre and UE3 is furthest away from the aggressor.。

极限交换机VDX6740和VDX6740T产品介绍说明书

极限交换机VDX6740和VDX6740T产品介绍说明书
VDX 674 0 T-1G Sw it ch
The VDX 674 0 T-1G ( Fig ure 3) offers 4 8 10 0 0 BA SE-T p ort s and t w o 4 0 Gb E QSFP+ p ort s. Each 4 0 Gb E p ort can b e b roken out int o four ind ep end ent 10 Gb E SFP+ p ort s, p rovid ing an ad d it ional eig ht 10 Gb E SFP+ p ort s for up link. A ll 4 8 10 0 0 BA SE-T p ort s can b e up g rad ed t o 4 8 10 GBA SE-T p ort s via t he Cap acit y on Dem and (CoD) soft w are license. Tw o 4 0 Gb E p ort s are enab led as p art of t he b ase license. The ad d it ional t w o 4 0 Gb E p ort s can b e up g rad ed via t he Port s on Dem and ( PoD) soft w are license.
- Meet s t od ay?s ap p licat ion d em and s w it h high perform ance and low latency
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Dat a Sheet

微秒基于双频同步的时钟同步模块说明书

微秒基于双频同步的时钟同步模块说明书

1Features•Two independent clock channels•Frequency and Phase Sync over Packet Networks •Frequency accuracy performance for WCDMA-FDD, GSM, LTE-FDD and femtocell applications •Frequency performance for ITU-T G.823 and G.824 synchronization interface, as well as G.8261 PNT PEC and CES interfaces•Phase Synchronization performance forWCDMA-TDD, Mobile WiMAX, TD-SCDMA and CDMA2000 applications•Client holdover and reference switching between multiple Servers•Server, client and boundary clock operation•Any input clock rate from 1kHz to 750MHz •Automatic hitless reference switching and digital holdover on reference fail•Digital PLLs filter jitter at 5.2 Hz, 14 Hz, 28 Hz, 56 Hz, 112 Hz, 224 Hz, 448 Hz or 896 Hz•Operates from a single crystal resonator or clock oscillator•Electrical phase alignment to input 1 Hz frame pulse with associated reference clock (ref/sync pairing)•Programmable synthesizers •Any output clock rate from 1Hz to 750MHz •Low output jitter for 10G PHYs•Six LVPECL outputs and six LVCMOS outputs•Field programmable via SPI/I 2C interfaceApplications•OTN muxponders and transponders •10Gigabit line cards•Synchronous Ethernet, SONET/SDH, Fibre Channel, XAUIMarch 2014Figure 1 - Functional Block DiagramZL30367Dual Channel IEEE 1588 & SynchronousEthernet Clock Line Card TranslatorShort Form Data SheetOrdering Information:ZL30367GDG2144 Pin LBGATraysPb Free Tin/Silver/Copper-40o C to +85o CPackage size: 13 x 13 mmDetailed FeaturesGeneral•Two independent clock channels•Operates from a single crystal resonator or clock oscillator•Configurable via SPI or I2C interfaceTime Synchronization Algorithm•External algorithm controls software digital PLL to adjust frequency & phase alignment•Frequency, Phase and Time Synchronization over IP, MPLS and Ethernet Packet Networks•Frequency accuracy performance for WCDMA-FDD, GSM, LTE-FDD and femtocell applications, with target performance less than ± 15 ppb.•Frequency performance for ITU-T G.823 and G.824 synchronization interface, as well as G.8261 PNT EEC, PNT PEC and CES interface specifications.•Phase Synchronization performance for WCDMA-TDD, Mobile WiMAX, TD-SCDMA and CDMA2000 applications with target performance less than ± 1 s phase alignment.•Time Synchronization for UTC-traceability and GPS replacement.•Client reference switching between multiple Servers•Client holdover when Server packet connectivity is lostElectrical Clock Inputs•Nine input references configurable as single ended or differential and two singled ended input references •Synchronize to any clock rate from 1kHz to 750MHz on differential inputs•Synchronize to any clock rate from 1kHz to 177.75MHz on singled-ended inputs•Synchronize to sync pulse and clock pair•Flexible input reference monitoring automatically disqualifies references based on frequency and phase irregularities•LOS•Single cycle monitor•Precise frequency monitor•Coarse frequency monitor•Guard soak timer•Per input clock delay compensationElectrical Clock Engine•Flexible two-stage architecture translates between arbitrary data rates, line coding rates and FEC rates •Internal state machine automatically controls mode of operation (free-run, locked, holdover)•Automatic hitless reference switching and digital holdover on reference fail•Physical-to-physical reference switching•Physical-to-packet reference switching•Packet-to-physical reference switching•Packet-to-packet reference switching•Selectable phase slope limiting•Supports ITU-T G.823, G.824 and G.8261 for 2048kbit/s and 1544kbit/s interfacesElectrical Clock Generation•Three programmable synthesizers•Six LVPECL outputs•Two LVPECL outputs per synthesizer•Generate any clock rate from 1Hz to 750MHz•Low output jitter for 10G PHYs•Meets OC-192, STM-64, 1 GbE & 10 GbE interface jitter requirements•Six LVCMOS outputs•Two LVCMOS outputs per synthesizer•Generate any clock rate from 1 Hz to 177.75MHz•Programmable output advancement/delay to accommodate trace delays or compensate for system routing paths•Outputs may be disabled to save powerAPI Software•Interfaces to 1588-capable PHY and switches with integrated timestamping•Abstraction layer for independence from OS and CPU, from embedded SoC to home-grown•Fits into centralized, highly integrated pizza box architectures as well as distributed architectures with multiple line cards and timing cardsInformation relating to products and services furnished herein by Microsemi Corporation or its subsidiaries (collectively “Microsemi”) is believed to be reliable. However, Microsemi assumes no liability for errors that may appear in this publication, or for liability otherwise arising from the application or use of any suchinformation, product or service or for any infringement of patents or other intellectual property rights owned by third parties which may result from such application or use. Neither the supply of such information or purchase of product or service conveys any license, either express or implied, under patents or other intellectual property rights owned by Microsemi or licensed from third parties by Microsemi, whatsoever. Purchasers of products are also hereby notified that the use of product in certain ways or in combination with Microsemi, or non-Microsemi furnished goods or services may infringe patents or other intellectual property rights owned by Microsemi.This publication is issued to provide information only and (unless agreed by Microsemi in writing) may not be used, applied or reproduced for any purpose nor form part of any order or contract nor to be regarded as a representation relating to the products or services concerned. The products, their specifications, services and other information appearing in this publication are subject to change by Microsemi without notice. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specific piece of equipment. It is the user’s responsibility to fully determine the performance and suitability of any equipment using such information and to ensure that any publication or data used is up to date and has not been superseded.Manufacturing does not necessarily include testing of all functions or parameters. These products are not suitable for use in any medical and other products whose failure to perform may result in significant injury or death to the user. All products and materials are sold and services provided subject to Microsemi’s conditions of sale which are available on request.Purchase of Microsemi’s I 2C components conveys a license under the Philips I 2C Patent rights to use these components in an I 2C System, provided that the system conforms to the I 2C Standard Specification as defined by Philips.Microsemi, ZL, and combinations thereof, VoiceEdge, VoicePort, SLAC, ISLIC, ISLAC and VoicePath are trademarks of Microsemi Corporation.TECHNICAL DOCUMENTATION - NOT FOR RESALEFor more information about all Microsemi productsvisit our Web Site at/timing-and-synchronization。

学术英语课后答案 unit1

学术英语课后答案 unit1

学术英语理工教师手册Unit 1 Choosing a TopicI Teaching ObjectivesIn this unit , you will learn how to:1.choose a particular topic for your research2.formulate a research question3.write a working title for your research essay4.enhance your language skills related with reading and listening materials presented in this unit II. Teaching Procedures1.Deciding on a topicTask 1Answers may vary.Task 21 No, because they all seem like a subject rather than a topic, a subject which cannot be addressed even by a whole book, let alone by a1500-wordessay.2Each of them can be broken down into various and more specific aspects. For example, cancer can be classified into breast cancer, lung cancer, liver cancer and so on. Breast cancer can have such specific topics for research as causes for breast cancer, effects of breast cancer and prevention or diagnosis of breast cancer.3 Actually the topics of each field are endless. Take breast cancer for example, we can have the topics like:Why Women Suffer from Breast Cancer More Than Men?A New Way to Find Breast TumorsSome Risks of Getting Breast Cancer in Daily LifeBreast Cancer and Its Direct Biological ImpactBreast Cancer—the Symptoms & DiagnosisBreastfeeding and Breast CancerTask 31 Text 1 illustrates how hackers or unauthorized users use one way or another to get inside a computer, while Text2 describes the various electronic threats a computer may face.2 Both focus on the vulnerability of a computer.3 Text 1 analyzes the ways of computer hackers, while Text 2 describes security problems of a computer.4 Text 1: The way hackers “get inside” a computerText 2: Electronic threats a computer facesYes, I think they are interesting, important, manageable and adequate.Task 41Lecture1:Ten Commandments of Computer EthicsLecture 2:How to Deal with Computer HackersLecture 3:How I Begin to Develop Computer Applications2Answersmay vary.Task 5Answers may vary.2 Formulating a research questionTask 1Text 3Research question 1: How many types of cloud services are there and what are they? Research question 2: What is green computing?Research question 3: What are advantages of the cloud computing?Text 4Research question 1: What is the Web 3.0?Research question 2: What are advantages and disadvantages of the cloud computing? Research question 3: What security benefits can the cloud computing provide?Task 22 Topic2: Threats of Artificial IntelligenceResearch questions:1) What are the threats of artificial intelligence?2) How can human beings control those threats?3) What are the difficulties to control those threats?3 Topic3: The Potentials of NanotechnologyResearch questions:1) What are its potentials in medicine?2) What are its potentials in space exploration?3) What are its potentials in communications?4 Topic4: Global Warming and Its EffectsResearch questions:1) How does it affect the pattern of climates?2) How does it affect economic activities?3) How does it affect human behavior?Task 3Answers may vary.3 Writing a working titleTask 1Answers may vary.Task 21 Lecture 4 is about the security problems of cloud computing, while Lecture 5 is about the definition and nature of cloud computing, hence it is more elementary than Lecture 4.2 The four all focus on cloud computing. Although Lecture 4 and Text 4 address the same topic, the former is less optimistic while the latter has more confidence in the security of cloud computing. Text3 illustrates the various advantages of cloud computing.3 Lecture 4: Cloud Computing SecurityLecture 5: What Is Cloud Computing?Task 3Answers may vary.4 Enhancing your academic languageReading: Text 11.Match the words with their definitions.1g 2a 3e 4b 5c 6d 7j 8f 9h 10i2. Complete the following expressions or sentences by using the target words listed below with the help of the Chinese in brackets. Change the form if necessary.1 symbolic 2distributed 3site 4complex 5identify6fairly 7straightforward 8capability 9target 10attempt11process 12parameter 13interpretation 14technical15range 16exploit 17networking 18involve19 instance 20specification 21accompany 22predictable 23profile3. Read the sentences in the box. Pay attention to the parts in bold.Now complete the paragraph by translating the Chinese in brackets. You may refer to the expressions and the sentence patterns listed above.ranging from（从……到）arise from some misunderstandings（来自于对……误解）leaves a lot of problems unsolved（留下很多问题没有得到解决）opens a path for（打开了通道）requires a different frame of mind（需要有新的思想）4.Translate the following sentences from Text 1 into Chinese.1) 有些人声称黑客是那些超越知识疆界而不造成危害的好人（或即使造成危害，但并非故意而为），而“骇客”才是真正的坏人。

操作系统概念课后答案

操作系统概念课后答案

操作系统概念课后答案操作系统概念课后答案【篇一：操作系统概念第七版答案(含编程代码)】> chapter 11.1 in a multiprogramming and time-sharing environment, several users share the system simultaneously. this situation can result in various security problems. a. what are two such problems?b. can we ensure the same degree of security in a time-shared machine as in a dedicated machine? explain your answer.answer:a. stealing or copying one’s programs or data; using system resources (cpu, memory, disk space, peripherals) without proper accounting.b. probably not, since any protection scheme devised by humans can inevitably be broken by a human, and the more complex the scheme, the more difficult it is to feel confident of its correct implementation.1.2 the issue of resource utilization shows up in different forms in different types of operating systems. list what resources must be managedcarefully in the following settings: a. mainframe or minicomputer systems b. workstations connected to serversc. handheld computersanswer:a. mainframes:memory and cpu resources, storage, network bandwidth.b. workstations: memory and cpu resoucesc. handheld computers: power consumption, memory resources.1.3 under what circumstances would a user be better off using a timesharing system rather than a pc or single-user workstation?answer: when there are few other users, the task is large, and the hardware is fast, time-sharingmakes sense. the full power of the system can be brought to bear o n the user’s problem. the problemcan be solved faster than on a personal computer. another case occurs when lots of other users need resources at the same time.a personal computer is best when the job is small enough to be executed reasonably on it and when performance is sufficient to execute the prog ram to the user’s satisfaction.1.4 which of the functionalities listed below need to be supported by the operating system for the following two settings: (a) handheld devices and (b) real-time systems. a. batch programmingb. virtual memoryc. time sharinganswer: for real-time systems, the operating system needs to support virtual memoryand time sharing in a fair manner. for handheld systems,the operating system needs to provide virtual memory, but does not need to provide time-sharing. batch programming is not necessary in both settings.1.5 describe the differences between symmetric and asymmetric multiprocessing.what are three advantages and one disadvantage of multiprocessor systems?answer: symmetric multiprocessing treats all processors as equals, and i/o can be processed on any cpu. asymmetric multiprocessing has one master cpu and the remainder cpus are slaves. the master distributes tasks among the slaves, and i/o isusually done by the master only.multiprocessors can save money by not duplicating power supplies,housings, and peripherals. they can execute programs more quickly and can have increased reliability. they are also more complex in both hardware and software than uniprocessor systems.1.6 how do clustered systems differ from multiprocessor systems? what is required for two machines belonging to a cluster to cooperate to provide a highly available service?answer: clustered systems are typically constructed by combining multiple computers into a single system to perform a computational task distributed across the cluster. multiprocessor systems on the other hand could be a single physical entity comprising of multiple cpus. a clustered system is less tightly coupled than a multiprocessorsystem.clustered systems communicate using messages, while processors in a multiprocessor system could communicate using shared memory.in order for twomachines to provide a highly available service, the state on the two machines should be replicated and should be consistently updated. when one of the machines fail, the other could then take-over the functionality of the failed machine.1.7 distinguish between the client-server and peer-to-peer models of distributed systems.answer: the client-server model firmly distinguishes the roles of the client and server. under this model, the client requests services that are provided by the server. the peer-to-peer model doesn’t have such strict roles. in fact, all n odes in the system are considered peers and thus may act as either clients or servers - or both. a node may request a service from another peer, or thenode may in fact provide such a service to other peers in the system.for example, let’s consider a syst em of nodes tha t share cooking recipes.under the client-server model, all recipes are stored with the server. if a client wishes to access a recipe, it must request the recipe from the specified server. using the peer-to-peer model, a peer node could ask other peer nodes for the specified recipe.the node (or perhaps nodes) with the requested recipe could provide it to the requesting node. notice how each peer may act as both a client (i.e. it may request recipes) and as a server (it may provide recipes.)1.8 consider a computing cluster consisting of twonodes running adatabase.describe two ways in which the cluster software can manage access to the data on the disk. discuss the benefits and disadvantages of each.answer: consider the following two alternatives: asymmetric clustering and parallel clustering. with asymmetric clustering, one host runs the database application with the other host simply monitoring it. if the server fails, the monitoring host becomes the active server. this is appropriate for providing redundancy. however, it does not utilize the potential processing power of both hosts. with parallel clustering, the database application can run in parallel on both hosts. the difficulty implementing parallel clusters is providing some form of distributed locking mechanism for files on the shared disk.1.9 how are network computers different from traditional personal computers? describe some usage scenarios in which it is advantageous to use network computers.answer: a network computer relies on a centralized computerfor most of its services. it can therefore have a minimal operating system to manage its resources. a personal computer on the other hand has to be capable of providing all of the required functionality in a standalonemanner without relying on a centralized manner. scenarios where administrative costs are high and where sharing leads to more efficient use of resources are precisely those settings where network computers are preferred.1.10 what is the purpose of interrupts? what are the differences between a trap and an interrupt? can traps be generated intentionally by a user program? if so, for what purpose?answer: an interrupt is a hardware-generated change-of-flow within the system. an interrupt handler is summoned to deal with the cause of the interrupt; control is then returned to the interrupted context and instruction. a trap is a software-generated interrupt. an interrupt can be used to signal the completion of an i/o to obviate the need for device polling. a trap can be used to call operating system routines or to catch arithmetic errors.1.11 direct memory access is used for high-speed i/o devices in order to avoid increasing the cpu′s execution load.a. how does the cpu interface with the device to coordinate the transfer?b. how does the cpu know when the memory operations are complete?c. the cpu is allowed to execute other programs while the dma controller istransferring data. does this process interfere with the execution of the user programs? if so, describe what forms ofinterference are caused.answer: the cpu can initiate a dma operation by writing values into special registers that can be independently accessed by the device.the device initiates the corresponding operation once it receives a command from the cpu. when the device is finished with its operation, it interrupts the cpu to indicate the completion of the operation.both the device and the cpu can be accessing memory simultaneously.the memory controller provides access to the memory bus in a fair manner to these two entities.a cpu might therefore be unable to issue memory operationsat peak speeds since it has to compete with the device in order to obtain access to the memory bus.1.12 some computer systems do not provide a privilegedmode of operation in hardware. is it possible to construct a secure operating system for these computer systems? give arguments both that it is and that it is not possible.answer: an operating system for a machine of this type would need to remain in control (or monitor mode) at all times. this could be accomplished by two methods:a. software interpretation of all user programs (like some basic,java, and lisp systems, for example). the software interpreter would provide, in software, what the hardware does not provide.b. require meant that all programs be written in high-level languages so that all object code is compiler-produced. the compiler would generate (either in-line or by function calls) the protection checks that the hardware is missing.1.13 give two reasons why caches are useful.what problems do they solve? what problems do they cause? if a cache can be made as large as the device for which it is caching (forinstance, a cache as large as a disk), why not make it that large and eliminate the device?answer: caches are useful when two or more components need to exchange data, and the components perform transfers at differing speeds.caches solve the transfer problem by providing a buffer of intermediate speed between the components. if the fast device finds the data it needs in the cache, it need not wait for the slower device. the data in the cache must be kept consistent with the data in the components. if a omponent has a data value change, and the datum is also in the cache, the cache must also be updated. this is especially a problem on multiprocessor systemswhere more than one process may be accessing adatum.acomponent may be eliminated by an equal-sized cache, but only if: (a) the cache and the component have equivalent state-saving capacity (that is,if the component retains its datawhen electricity is removed, the cache must retain data as well), and (b) the cache is affordable, because faster storage tends to be more expensive.1.14 discuss, with examples, how the problem of maintaining coherence of cached data manifests itself in the following processing environments:a. single-processor systemsb. multiprocessor systemsc. distributed systemsanswer: in single-processor systems, the memory needs to be updated when a processor issues updates to cached values. these updates can be performed immediately or in a lazy manner. in amultiprocessor system,different processors might becaching the same memory location in its local caches. when updates are made, the other cached locations need to be invalidated or updated. in distributed systems, consistency of cached memory values is not an issue. however, consistency problems might arise when a client caches file data.1.15 describe a mechanism for enforcing memory protectionin order to prevent a program from modifying the memory associated with other programs.answer: the processor could keep track of what locations are associated with each process and limit access to locations that are outside of a program’s extent. information regarding the exten t of a program’s memory could be maintained by using base and limits registers and by performinga check for every memory access.1.16 what network configuration would best suit the following environments? a. a dormitory floorb. a university campusc. a stated. a nationanswer:a. a dormitory floor - a lan.b. a university campus - a lan, possible a wan for very large campuses.c. a state - awan.d. a nation - a wan.1.17 define the essential properties of the following types of operating systems: a. batchb. interactivec. time sharingd. real timee. networkf. parallelg. distributedh. clusteredi. handheld【篇二：操作系统概念_第六版_重点部分_中文答案-】urposes of an operating system?1 to provide an environment for a computer user to execute programs on computer hardware in a convenient and ef?cient manner.2 to allocate the separate resources of the computer as needed to solve the problem given. the allocation process should be as fair and ef?cient as possible.3 as a control program it serves two major functions: (1) supervision of the execution of user programs to prevent errors and improper use of the computer, and (2) manage- ment of the operation and control of i/o devices.环境提供者，为计算机用户提供一个环境，使得能够在计算机硬件上方便、高效的执行程序? 资源分配者，为解决问题按需分配计算机的资源，资源分配需尽可能公平、高效 ? 控制程序监控用户程序的执行，防止出错和对计算机的不正当使用管理i/o 设备的运行和控制1.6 define the essential properties of the following types of operating systems: a. batchb. interactivec. time sharingd. real timee. networkf. distributeda. batch. jobs with similar needs are batched together andrun through the computer as a group by an operator or automatic job sequencer. performance is increased by attempting to keep cpu and i/o devices busy at all times through buffering, off-line operation, spooling, and multiprogramming. batch is good for executing large jobs that need little interaction; it can be submitted and picked up later.b. interactive. this system is composed of many short transactions where the results of the next transactionmay be unpredictable. response time needs to be short (seconds) since the user submits and waits for the result.c. time sharing.thissystemsuses cpu scheduling and multiprogramming to provide economical interactive use of a system. the cpu switches rapidly from one user toanother. instead of having a job de?ned by spooled card images, each program readsits next control card from the terminal, and output is normally printed immediately to the screen.d. real time. often used in a dedicated application, this system reads information from sensors and must respond withina ?xed amount of time to ensure correct perfor- mance.e. network.f. distributed.this system distributes computation among several physical processors. the processors do not share memory or a clock. instead, each processor has its own local memory. they communicate with each other through various communication lines, such as a high-speed bus or telephone line.a. batch相似需求的job分批、成组的在计算机上执行，job由操作员或自动job程序装置装载；可以通过采用buffering, off-line operation, spooling, multiprogramming 等技术使cpu 和 i/o不停忙来提高性能批处理适合于需要极少用户交互的job。

peer-to-peervide...

peer-to-peervide...

PEER-TO-PEER VIDEO ON DEMAND:CHALLENGES AND SOLUTIONS Vijay S.Pai∗,Yung Ryn Choe†,Jagadeesh Dyaberi,Derek Schuff,Karthik KannanPurdue UniversityWest Lafayette,IN47907ABSTRACTThe challenges and solutions required for peer-to-peer video-on-demand(P2P V oD)provided by afixed provider such as a cable company are fundamentally different from those seen in traditional P2P networks or client-server V oD solutions.Un-like traditional P2P networks,the end nodes(set top boxes with DVR capabilities)are largely under control of the system provider.Consequently,issues like churn and free-loading are less substantial.Unlike client-server solutions,there is always a readily-available resource of peer nodes able to contribute even if they are not using the VoD service!This paper explores requirements for efficient preloading of V oD movie data onto numerous customer set-top boxes. This research is currently exploring mathematical program-ming algorithms that minimize uplink traffic,given a pop-ularity model for various pieces of content and information about storage and bandwidth capacity constraints at the cus-tomer nodes.Given the complex non-linear nature of P2P interactions,these mathematical programs require non-linear optimization approaches or heuristic solutions.However, even heuristic solutions would likely provide substantial ad-vantages over simple dynamic allocation.Index Terms—Video-on-demand,mathematical pro-gramming1.INTRODUCTIONAs systems such as voice,video,and data communication merge onto a single IP-network delivery platform,users are likely to benefit with a greater number of choices and more content control at their disposal[1].Given the numerous ad-vantages of doing so,cable companies have made significant investments in systems that seek to deliver high-bandwidth digital content(e.g.,Video-On-Demand service for full length,high-definition movies)to consumers.However in the current unicast data delivery model,all the movie data is streamed from the regional or national-level video hubs to the requesting viewers.This unicast data delivery model puts a considerable amount of strain on the regional/national servers ∗This work is supported in part by the National Science Foundation under Grant F-0532448and CCF-0621457.†Currently at Sandia Livermore National Labs and on the uplink connection between the local community switch and the local video hubs.The uplinks between the communities and the server hubs thus become the bottleneck in determining the total number of concurrent viewers,and increasing this number will only lead to more usable systems for the users and greater potential revenue for the network providers.2.PROPOSED SOLUTION AND CHALLENGES The viewers in this environment are users of set-top boxes provided by the networks.Although set-top boxes can store viewer-selected content through resources such as DVR,they are essentially largely under control of the system provider. Thus,the system provider may use their resources as a way of extending the capabilities of the network.A feasible solution to reduce uplink load and extend the network is to use P2P communication among set-top boxes in a community.This approach could exploit any unused bandwidth in the com-munity network and any unused capacity in the user set-top boxes.In our previous work we modified the BitTorrent proto-col to enable peers(set-top boxes)to stream data to each other[2].Our results showed that with a modified piece-picker policy,data demand on the server is reduced by upto 70-90%when compared to simple unicast delivery model, thus validating the use of P2P communication for streaming. Our system was evaluated with a single movie with no con-straints placed on the piece-popularity,as this is most similar to the existing BitTorrentfile swarm model[3].However, using individual swarms for videos would mismanage and/or underutilize the potential resources available in a network of set-top boxes.We now plan to further our research into P2P communi-cation for video content delivery by extending our system to consider the streaming of all movies available from the V oD provider.We have identified several research problems that arise by considering an extended system.First,porting a traditional P2P model into a environment that is largely centrally-controlled would underutilize the re-sources.If end nodes are entirely responsible for making de-cisions about which content to store based on their own on-demand viewing,the system will not be increasing its capabil-ities whenever end nodes are idle.This is a substantial issue in situations like home V oD where we would expect idleness for most of the day followed by a brief period of high activity in the evening and early night.Instead,the system should try to preload desired data onto the set-top boxes and thus make all set-top boxes active participants in the P2P network even if they are not consuming P2P resources.Second,the issue of set-top box capacity becomes a con-cern when we consider all the content available from the provider(which can reach thousands of movies).The total capacity among all the set-top boxes in a community is far less than the capacity needed to store all the movies,so only a subset of the total content can be stored in the community. Further,if the movies are encoded in high-definition,capacity becomes an even bigger constraint.Third,bandwidth is closely tied with capacity as both must be considered jointly to maximize overall streaming ef-ficiency.This is a concern as all networks currently exhibit substantial asymmetry between the uplink and downlink bi-trates at any given end node(typically about an order of mag-nitude).If each end node has an uplink of1Mbps,it would require six sources simultaneously contributing data to satisfy a single request for a HD-quality streaming movie encoded at6Mbps;each of these sources would be fully saturating its uplink.This issue now relates back to capacity,because offloading a substantial amount of streaming traffic onto the P2P network requires that enough copies of the data exist in the network to account for the asymmetry in uplink and down-link rates.This requires replication,which reduces the effec-tive aggregate capacity in the network and makes the subset of content that can be stored in the network an even smaller fraction of the total.Because the P2P network can only store a subset of the data content available,any preloading solution must intelli-gent choose which data to load and replicate.An effective decision would require an understanding of the popularity of different pieces of content,as the greatest benefits would arise from replicating the most popular content.At the same time, the high demand for these most popular videos would require extensive replication to be able to support as many simultane-ous requests as are likely to arrive.We are currently exploring different intelligent capacity allocation policies using mathematical models that would seek to maximize the streaming availability and efficiency within the community network.Putting together capacity and bandwidth constraints,we are developing mathemati-cal programming models that build up a“presence matrix”of pieces of content by carefully considering capacity con-straints(making sure that no given node is assigned too much data)and bandwidth constraints(making sure that no node’s uplink is overly strained by heavily replicating the most pop-ular pieces of content and distributing the popular content across different sets of nodes so that no node is particularly more demanded than others)while optimizing for an objec-tive function.The current objective function is to minimize the aggregate bandwidth demand at the servers.3.SUMMARY AND FUTURE WORK Although P2P V oD offers substantial performance challenges, intelligent preloading algorithms should enable effective uti-lization of system resources to allow scalability beyond the saturation point of the current client-server model.Conse-quently,this should be an important area for short-term and long-term contributions.Future work must consider the robustness and security of the proposed P2P delivery model.One of the biggest is-sues in traditional P2P research is churn:Nodes come and go randomly which changes the network dynamics.Capacity and bandwidth can change instantaneously and the network should be able to adapt to the change.Although less than a traditional P2P system,a set-top box network can still expe-rience churn caused by power failures or users turning off the power on their node;additionally,a set-top box is in a state of“virtual churn”if its uplink is being used entirely for other purposes at a given time.We would like to explore robust-ness and resilience against churn in the system.Additionally, using set-top boxes to make decisions and serve data intro-duces an increased possibility of malicious users looking to manipulate the system to their own advantage.It is thus also important to protect content and detect and prevent harmful activity.Although cable companies may deploy a setup like this for V oD,they can use it to gain additional benefits in other domains as data traffic is also carried on the same network as videos.Thus,the infrastructure that results from these efforts may benefit other applications.For example,this peer-to-peer setup may also act as a cache for Web content or blocks of other commonly-accessedfiles,allowing a general reduc-tion in uplink traffic from non-V oD sources as well.Such efforts may be important when dealing with high-bandwidth events such as software updates that affect all end-users at once.4.REFERENCES[1]Yih-Farn Chen et al.,“When is P2P Technology Bene-ficial for IPTV Services,”in Proceedings of the17th In-ternational Workshop on Network and Operating System Support for Digital Audio and Video,May2007.[2]Yung Ryn Choe,Derek L.Schuff,Jagadeesh M.Dyaberi,and Vijay S.Pai,“Improving vod server efficiency with bittorrent,”in MULTIMEDIA’07:Proceedings of the 15th international conference on Multimedia,New York, NY,USA,2007,pp.117–126,ACM.[3]Clive Thompson,“The BitTorrent Effect,”Wired Maga-zine,January2005.。

以制度创新引领城市更新

以制度创新引领城市更新

以制度创新引领城市更新+U R B A N R E G E N E R A T IO N L E D B Y 丨N S T IT U T IO N A L IN N O V A T IO N 王世福易智康WANG Shifu;YI Zhikang【摘要】城市更新反映了一座城市的治理能力，是一整套有关建成环境维育和再开发的制度体系。

回顾城市更新的内涵发展与制度变迁历程，制度创新决定着城市更新的模式与质量，引领着 城市更新的创新实践。

我国从快速城市化走向深度城市化，应对城市问题的复杂性，维护建成环 境的持续高品质，保障城市再开发的公共性，提 高城市更新的善治性，成为新时期城市更新的制 度建设需求。

当前中国城市更新模式存在“房地 产化”的路径依赖、更新实施的系统性目标缺失、更新管理的协同性难以建立等制度困境，对 此，本文提出了补齐短板、面向建成环境高品质 维育的制度建立，强调善治、面向可持续再开发 的制度完善等思考，并对未来城市更新的制度创新做了综合性的展望。

【关键詞】城市更新；制度创新；建成环境；维 育；善治ABSTRACT: U rb a n r e g e n e r a ti o n is a se t o f in s titu tio n a l sy s te m s a s s o c ia te d w ith the m a in te n a n c e an d re d e v e lo p m e n t o f th e b u ilt environm ent,representing the governance capacity o f a city.A fter review ing the developm ent and institutional changes o f urban regeneration,this paper argues that institutional innovation determines the m odel and quality o f urban regeneration and leads to the transform ation o f urban regeneration. As urbanization in C hina is m oving into a new stage,the urban regeneration institution urgently needs to be improved to respond to the complexity o f urban issu es,m aintenance o f a hig h-q u ality environm ent,the public good o f redevelopm ent, and good governance.However,urban regeneration is facing m any institutional d ifficu lties,such as over-reliance on real estate developm ent,lack of integrity and system aticness in land developm ent,and in su fficien t co o rd in atio n.A cco rd in g ly,thep a p e r p o in ts o u t th a t th e u rb an re g e n e ra tio ninstitution should reinforce weak links and focus onmaintenance o f the high-quality built environm ent,and due attention should be paid to good governanceand su stain ab le re d e v e lo p m e n t.In a d d itio n,itmakes a comprehensive outlook on the institutionalinnovation o f urban regeneration.K E Y W O R D S:urban reg en eratio n;institutionalinnovation;built environm ent;m aintenance;goodgovernance1引言经过自改革开放以来的城市快速发展，中国2019年常住人口城镇化率已超过了60%.中国的城市化发展已经从快速城市化转向深度城市化阶段.城市建设的土地资源约束日益趋紧.发展重点从增量用地转向存量用地.城市更新将成为城市迈向高质量发展的新动能.深刻影响着城市经济社会和空间结构的转型。

2024年6月英语六级试卷

2024年6月英语六级试卷

2024年6月英语六级试卷一、写作（15%）Directions: For this part, you are allowed 30 minutes to write an essay on the topic "The Impact of Artificial Intelligence on Employment". You should write at least 150 words but no more than 200 words.二、听力理解（35%）Section A.Directions: In this section, you will hear three news reports. At the end of each news report, you will hear two or three questions. Both the news report and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D).News Report 1.Questions 1 - 2 are based on the news report you have just heard.1. A) The development of a new energy source.B) The discovery of a new species.C) A major breakthrough in medical research.D) An environmental protection project.2. A) It has been widely applied in hospitals.B) It is still in the experimental stage.C) It has caused some ethical debates.D) It is too expensive for general use.News Report 2.Questions 3 - 4 are based on the news report you have just heard.3. A) To promote international trade.B) To attract more tourists.C) To improve transportation infrastructure.D) To enhance cultural exchanges.4. A) By building more high - speed railways.B) By offering more favorable policies.C) By strengthening cooperation with neighboring countries.D) By developing new tourism products.News Report 3.Questions 5 - 7 are based on the news report you have just heard.5. A) A decrease in the number of students studying abroad.B) An increase in the quality of domestic education.C) Changes in the trend of overseas study.D) Problems faced by international students.6. A) The high cost of living abroad.B) The fierce competition in the job market.C) The improvement of domestic education resources.D) The influence of the global economic situation.7. A) They are more likely to choose Asian countries.B) They tend to focus on high - tech fields.C) They are more interested in short - term study programs.D) They prefer to study in their own countries.Section B.Directions: In this section, you will hear two long conversations. At the end of each conversation, you will hear four questions. Both the conversation and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D).Conversation 1.Questions 8 - 11 are based on the conversation you have just heard.8. A) She is preparing for an exam.B) She is looking for a part - time job.C) She is writing a research paper.D) She is planning a trip.9. A) In the library.B) In the cafeteria.C) In the dormitory.D) In the classroom.10. A) It requires a lot of reading.B) It has a strict time limit.C) It needs to be done in groups.D) It involves field research.11. A) Help her find relevant materials.B) Give her some advice on writing.C) Join her study group.D) Share his own experience.Conversation 2.Questions 12 - 15 are based on the conversation you have just heard.12. A) A new movie.B) A best - selling book.C) A popular TV show.D) A famous actor.13. A) The interesting plot.B) The excellent acting.C) The beautiful scenery.D) The profound theme.14. A) He has seen it many times.B) He doesn't like it at all.C) He thinks it's just so - so.D) He hasn't seen it yet.15. A) Watch it together this weekend.B) Recommend some other movies.C) Discuss the story in detail.D) Buy the DVD of the movie.Section C.Directions: In this section, you will hear three passages. At the end of each passage, you will hear three or four questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D).Passage 1.Questions 16 - 18 are based on the passage you have just heard.16. A) The origin of language.B) The development of language.C) The importance of language in communication.D) The differences between languages.17. A) By imitating the sounds of nature.B) By using gestures and facial expressions.C) By making up random sounds.D) By combining existing words.18. A) It helps people express complex ideas.B) It enables people to communicate across cultures.C) It reflects the creativity of human beings.D) It is constantly evolving.Passage 2.Questions 19 - 22 are based on the passage you have just heard.19. A) How to choose a suitable career.B) The factors influencing career choices.C) The importance of career planning.D) Different types of careers.20. A) Personal interests.B) Family expectations.C) Social status.D) Economic benefits.21. A) They are more likely to be satisfied with their jobs.B) They can earn more money.C) They can get promoted more easily.D) They are less likely to change their jobs.22. A) Do some internships.B) Take career assessment tests.C) Consult career counselors.D) Follow the advice of parents.Passage 3.Questions 23 - 25 are based on the passage you have just heard.23. A) The history of modern architecture.B) The characteristics of different architectural styles.C) The influence of architecture on people's lives.D) The development of sustainable architecture.24. A) It is more energy - efficient.B) It is more beautiful.C) It is more expensive.D) It is more difficult to construct.25. A) Using recycled materials.B) Designing more open spaces.C) Incorporating natural elements.D) Adopting new construction techniques.三、阅读理解（35%）Section A.Directions: In this section, there is a passage with ten blanks. You are required to select one word for each blank from a list of choices givenin a word bank following the passage. Read the passage through carefully before making your choices. Each choice in the bank is identified by a letter. Please mark the corresponding letter for each item on Answer Sheet 2. You may not use any of the words in the bank more than once.The Internet has become an integral part of our daily lives. It has_(26)_ the way we communicate, learn, work, and entertain ourselves. With just a few clicks, we can access a vast amount of information from all over the world. However, this convenience also comes with some _(27)_. One of the major concerns is the issue of privacy. When we use the Internet, we often leave behind a digital _(28)_ that can be used by others for various purposes. For example, companies may collect our personal information to target us with advertisements. Another problem is the spread of false information. In the age of social media, anyone can _(29)_ information without proper verification, which can lead to misunderstandings and even social unrest. To address these issues, governments and Internet companies need to work together. Governments should _(30)_ laws to protect users' privacy and regulate the spread of false information. Internet companies, on the other hand, should take _(31)_ measures to ensure the security of users' data and promote the authenticity of information.Word Bank:A) transformed.B) challenges.C) footprint.D) publish.E) enforce.F) responsible.G) limited.H) access.I) privacy.J) awareness.Section B.Directions: In this section, you will read several passages. Each passage is followed by several questions based on its content. You are to choose the best answer to each question from the four choices marked A), B), C) and D).Passage 1.Questions 32 - 36 are based on the following passage.The concept of "green jobs" has gained increasing attention in recent years. Green jobs are those that contribute to environmental protection and sustainable development. These jobs can be found in various sectors, suchas renewable energy, energy - efficient building, and waste management. The growth of green jobs is driven by several factors. Firstly, the increasing awareness of environmental issues has led to a greater demand for environmentally - friendly products and services. Secondly, government policies and incentives play an important role. Many governments around the world are providing subsidies and tax breaks to encourage the developmentof green industries. Thirdly, technological advancements have made it possible to develop more efficient and cost - effective green technologies.However, the development of green jobs also faces some challenges. One of the challenges is the lack of trained personnel. Since green jobs often require specialized knowledge and skills, there is a shortage of workers who are qualified to fill these positions. Another challenge is the high cost of some green technologies, which may limit their widespread adoption.32. What are green jobs according to the passage?A) Jobs that are related to plants and forests.B) Jobs that are only available in the environmental protection department.C) Jobs that contribute to environmental protection and sustainable development.D) Jobs that require workers to wear green uniforms.33. What drives the growth of green jobs?A) Only the increasing awareness of environmental issues.B) The increasing awareness of environmental issues, governmentpolicies and incentives, and technological advancements.C) Only government policies and incentives.D) Only technological advancements.34. What is one of the challenges faced by the development of green jobs?A) There are too many trained personnel.B) The lack of trained personnel.C) The low cost of green technologies.D) The over - adoption of green technologies.35. Which of the following sectors may not have green jobs?A) Renewable energy.B) Energy - efficient building.C) Traditional coal mining.D) Waste management.36. What can be inferred from the passage about green jobs?A) They are not very important for the future.B) They will develop without any difficulties.C) They have both opportunities and challenges.D) They are only popular in developed countries.Passage 2.Questions 37 - 41 are based on the following passage.In the digital age, e - books have become increasingly popular. They offer several advantages over traditional printed books. For one thing, e - books are more convenient. You can carry a whole library of e - books on a single device, such as a tablet or an e - reader. This means you can have access to a wide range of reading materials wherever you are. For another, e - books are often cheaper than their printed counterparts. Publishers can save on the cost of printing and distribution, and these savings can be passed on to the consumers.However, e - books also have some disadvantages. One problem is that reading e - books for a long time may cause eye strain. The backlit screens of e - readers and tablets can be tiring on the eyes, especially in low - light conditions. Another issue is that some people simply prefer the feelof a physical book in their hands. The texture of the paper, the smell of the ink, and the act of turning the pages all contribute to the reading experience for these people.37. What are the advantages of e - books?A) They are more expensive.B) They are less convenient.C) They are more convenient and often cheaper.D) They are only available on one device.38. Why are e - books often cheaper?A) Because publishers don't want to make money.B) Because publishers can save on the cost of printing and distribution.C) Because e - books are of lower quality.D) Because the government subsidizes e - books.39. What is one of the disadvantages of e - books?A) They can't be read on any device.B) They may cause eye strain.C) They are always more expensive than printed books.D) They have no page - turning function.40. Who may not like e - books according to the passage?A) People who like to read a lot.B) People who care about the cost.C) People who prefer the feel of a physical book.D) People who are always on the go.41. What can be concluded from the passage about e - books?A) They will completely replace printed books in the future.B) They are not as good as printed books in any aspect.C) They have both pros and cons.D) They are only suitable for young people.Section C.Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on Answer Sheet 2.Passage 1.Questions 42 - 46 are based on the following passage.The sharing economy has emerged as a new economic model in recent years. It is based on the idea of sharing under - utilized resources, such as cars, houses, and tools. Platforms like Uber and Airbnb have become very popular, allowing people to earn extra income by sharing their assets.One of the main benefits of the sharing economy is that it can make more efficient use of resources. For example, instead of having a large number of cars sitting idle in parking lots, they can be used by others through car - sharing services. This can also reduce the need for new production, which is beneficial for the environment. Another advantage is that it can provide more affordable options for consumers. For instance, staying in an Airbnb accommodation is often cheaper than a hotel.However, the sharing economy also faces some challenges. One issue is the lack of regulation. Since it is a relatively new model, there are not enough laws and regulations to ensure fair competition and protect consumers. For example, some Uber drivers may not have proper insurance, which can pose a risk to passengers. Another problem is the quality control. It can be difficult to ensure the quality of shared resources, such as the cleanliness and safety of an Airbnb rental.42. What is the sharing economy based on?A) Buying new resources.B) Sharing under - utilized resources.C) Producing more resources.D) Wasting resources.43. What are the benefits of the sharing economy?A) It can make resources less efficient.B) It can only provide expensive options for consumers.C) It can make more efficient use of resources and provide more affordable options for consumers.D) It has no benefits at all.44. What are the challenges faced by the sharing economy?A) The over - regulation.B) The lack of regulation and quality control.C) The too - strict quality control.D) The high cost of production.45. Why is the lack of regulation a problem in the sharing economy?A) Because it ensures fair competition.B) Because it protects consumers.C) Because there are not enough laws and regulations to ensure fair competition and protect consumers.D) Because it makes the sharing economy too popular.46. What can be inferred about the sharing economy from the passage?A) It will disappear soon.B) It has both positive and negative aspects.C) It is only suitable for developed countries.D) It is a perfect economic model.Passage 2.Questions 47 - 50 are based on the following passage.Cultural heritage is an important part of a nation's identity. It includes historical buildings, artworks, traditions, and languages. Protecting cultural heritage is not only important for preserving anation's past but also for its future development.One of the ways to protect cultural heritage is through restoration. Restoration projects can bring old historical buildings back to life, allowing people to experience the past. For example, the restoration of the Forbidden City in China has made it a popular tourist destination, attracting millions of visitors every year. Another way is through education. By teaching people about their cultural heritage, they can develop a sense of pride and ownership, and be more likely to protect it.However, protecting cultural heritage also faces some challenges. One challenge is the lack of funds. Restoration projects can be very expensive, and many countries may not have enough money to carry out large - scale restoration work. Another challenge is the impact of modernization. As cities develop, some historical buildings may be demolished to make way for new construction.47. What is cultural heritage according to the passage?A) Only historical buildings.B) Only artworks.C) Historical buildings, artworks, traditions, and languages.D) Only modern buildings.48. Why is protecting cultural heritage important?A) Only for preserving a nation's past.B) Only for a nation's future development.C) For both preserving a nation's past and its future development.D) For no particular reason.49. What are the ways to protect cultural heritage?A) Only through restoration.B) Only through education.C) Through restoration and education.D) Through demolition.50. What are the challenges faced by protecting cultural heritage?A) The lack of funds and the impact of modernization.B) The over - abundance of funds and the lack.。

计算机网络原理习题讲解

计算机网络原理习题讲解

Chapter I1. What is the difference between a host and an end system? List the types of endsystems. Is a Web server an end system?2. What is a client program? What is a server program? Does a server program requestand receive services from a client program?3. List six access technologies. Classify each one as residential access, companyaccess, or mobile access.4. Dial-up modems, HFC, and DSL are all used for residential access. For each ofthese access technologies, provide a range of transmission rates and comment on whether the transmission rate is shared or dedicated.5. Describe the most popular wireless Internet access technologies today. Compareand contrast them.6. What advantage does a circuit-switched network have over a packet-switchednetwork? What advantages does TDM have over FDM in a circuit-switched network?7. Consider sending a packet from a source host to a destination host over a fixedroute. List the delay components in the end-to-end delay. Which of these delays are constant and which are variable?8. How long does it take a packet of length 2,000 bytes to propagate over a linkof distance 2,000 km, propagation speed 8102⨯ m/s, and transmission rate 2 Mbps? More generally, how long does it take a packet of length L to propagate over a link of distance d, propagation speed s, and transmission rate R bps? Does this delay depend on packet length? Does this delay depend on transmission rate?9. What are the five layers in the Internet protocol stack? What are the principalresponsibilities of each of these layers?10. Which layers in the Internet protocol stack does a router process? Which layersdoes a link-layer switch process? Which layers does a host process?11. What is an application-layer message? A transport-layer segment? A network-layerdatagram? A link-layer frame?12. This elementary problem begins to explore propagation delay and transmissiondelay, two central concepts in data networking. Consider two hosts, A and B, connected by a single link of rate R bps. Suppose that the two hosts are separated by m meters, and suppose the propagation speed along the link is s meters/sec. Host A is to send a packet of size L bits to Host B.a. Express the propagation delay, prop d , in terms of m and s.b. Determine the transmission time of the packet,trans d , in terms of L and R.c. Ignoring processing and queuing delays, obtain an expression for the end-to-end delay.d. Suppose Host A begins to transmit the packet at time t = 0. At time trans d t =,where is the last bit of the packet?e. Suppose prop d is greater than trans d . At time t = trans d ,where is the first bit of the packet?f. Suppose prop d is less than trans d . At time t = trans d , where is the first bit of the packet?g. Suppose 8105.2⨯=s , L = 100bits, and R = 28 kbps. Find the distance m so that prop d equals trans d .13. In modern packet-switched networks, the source host segments long,application-layer messages (for example, an image or a music file) into smaller packets and sends the packets into the network. The receiver then reassembles the packets back into the original message. We refer to this process as message segmentation. Figure 1.24 illustrates the end-to-end transport of a message with and without message segmentation. Consider a message that is 6108⨯ bits long that is to be sent from source to destination in Figure 1.24. Suppose each link in the figure is 2 Mbps. Ignore propagation, queuing, and processing delays.a. Consider sending the message from source to destination without message segmentation. How long does it take to move the message from the source host to the first packet switch? Keeping in mind that each switch uses store-and-forward packet switching, what is the total time to move the message from source host to destination host?b. Now suppose that the message is segmented into 4,000 packets, with each packet being 2,000 bits long. How long does it take to move the first packet from source host to the first switch? When the first packet is being sent from the first switch to the second switch, the second packet is being sent from the source host to the first switch. At what time will the second packet be fully received at the first switch?c. How long does it take to move the file from source host to destination hostwhen message segmentation is used? Compare this result with your answer in part(a) and comment.d. Discuss the drawbacks of message segmentation.14.下列说法中,正确的是( )。

极限网络ExtremeSwitching X450-G2系列产品数据表说明书

极限网络ExtremeSwitching X450-G2系列产品数据表说明书

Data SheetExtremeSwitching ™ X450-G2 SeriesScalable advanced aggregation switch with ExtremeXOS® modular operating system.The ExtremeSwitching X450-G2 series is based on Extreme Networks revolutionary ExtremeXOS, a highly resilient OS that provides continuous uptime, manageability and operational efficiency. Each switch offers the same high-performance, nonblocking hardware technology, in the Extreme Networks tradition of simplifying network deployments through the use of common hardware and software throughout the network.The X450-G2 switches are effective campus edge switches with IEEE802.3at PoEplus. The X450-G2 series is also an option for DSLAM or CMTS aggregation, or for active Ethernet access.Comprehensive Security Management• Role-based policy and host integrity enforcement, and identity management• Universal Port Dynamic Security Profiles to provide fine granular security policies in the network • Threat detection and response instrumentation to react to network intrusion with CLEAR-Flow Security Rules Engine • Denial of Service (DoS) protection and IP security against man-in-the-middle and DoS attacks to harden the network infrastructure • Role-based Policy enables support for policy profiles to secure and provision network resources based upon the role the user or device plays within the network.HighlightsPerformance• 48-port or 24-port Gigabit Ethernet models• 4 ports of SFP+ 10GbE/1GbE or 4 ports of SFP 1GbE on front faceplate • All configurations Non-blocking full duplex• Copper and PoE-Plus models • Built-in 21Gbps stacking ports on rear panel for all models (SummitStack-V84)• Optional SummitStack-V 40 Gbps stacking across two 10Gb front- panel portsFeatures• Secure Network Accessthrough Rolebased policy or Identity Management • Front-to-Back airflow • Modular PoE power supplies• 850W of PoE-Plus budget with 1 PSU • 1440W of PoE-Plus Budget with 2 PSUs• Y .1731 OAM Measurements in hardware for accuracy • Energy Efficient Ethernet – IEEE 802.3az• Hot-swappable fan tray and PoEpower suppliesFlexible Port ConfigurationAll models come equipped with either 4 ports of SFP+ 10 GbE or 4 ports of SFP 1GbE resident on the faceplate of each model.High-Performance StackingUp to eight X450-G2 switches can be stacked usingtwo different methods of stacking: SummitStack-V, and SummitStack-V84. Each X450-G2 unit comes equipped with 2 ports of 21 Gigabit stacking ports via a QSFP interface. Standard passive 40Gb copper cables can be used for stacking X450-G2s together. SUMMITSTACK-V — Flexible Stacking Over10 Gigabit EthernetExtremeXOS supports the SummitStack-V capability using 2 of the native 10 GbE ports on the faceplate as stacking ports, enabling the use of standard cabling and optics technologies used for 10 GbE SFP+. SummitStack-V provides long-distance stacking connectivity of up to 40 km while reducing the cable complexity of implementing a stacking solution. SummitStack-V is compatible withX440-G2, X450-G2 and X460-G2 switches with 10Gb uplinks, as well as X480, X670, X670V, X670-G2 and X770 switches. SummitStack-V enabled 10 GbE ports must be physically direct-connected with all switches running the same version of ExtremeXOS.SUMMITSTACK-V84 — High-Speed Stacking Over Dedicated Stacking PortsThe X450-G2 also supports high-speed 84 Gbps stacking, which is ideal for demanding applications where a high volume of traffic traverses through the stacking links,yet bandwidth is not compromised through stacking. SummitStack-V84 is supported over passive copper QSFP cables (up to 7m). SummitStack-V84 is only supported on X450-G2 switches running the same version of ExtremeXOS.NOTE: SummitStack-V84 is NOT interoperable with SummitStack-V80 Intelligent SwitchingThe X450-G2 Series supports sophisticated and intelligent Layer 2 switching, as well as Layer 3 IPv4/IPv6 routing including policy-based switching/routing, Provider Bridges, bidirectional ingress and egress Access Control Lists, and bandwidth control by 8 Kbps granularity both for ingress and egress.IEEE 802.3AT PoE-PlusIEEE 802.3af Power over Ethernet has been widely usedin the campus enterprise edge network for Ethernet-powered devices such as wireless access points, Voiceover IP phones, and security cameras. Ethernet port extenders such as Extreme Networks ReachNXT™ 100-8t can also utilize PoE, making installation and management easier and reducing maintenance costs. The newer IEEE 802.3at PoEplus standard expands upon Power over Ethernet by increasing the power limit up to 30 watts, and by standardizing power negotiation by using LLDP. TheX450-G2 supports IEEE 802.3at PoE-plus and supports standards-compliant PoE devices today and into the future. Role-Based PolicyUtilizing ExtremeManagement Policy Management, the role-based policy framework empowers a network administrator to define distinct roles or profiles that represent industry specific operational groups that may exist in an education or a business environment (e.g., administrator, teacher, student, guest). Each defined role is granted individualized access to specific network services and applications and these access privileges remain associated with users as they move across both wired and wireless network access points. Users can be authenticated via IEEE 802.1X, MAC address, or web authentication, and then assigned a pre-defined operational role. Network operations can be seamlessly tailored to meet business-oriented requirements by providing each role with individualized access to network services and applications, thus aligning network resource utilization with business goals and priorities.Audio Video BridgingThe X450-G2 series supports IEEE 802.1 Audio Video Bridging (AVB) to enable reliable, real-time audio/video transmission over Ethernet. AVB technology delivers the quality of service required for today’s high-definition and time-sensitive multimedia streams.Ordering NotesThe X450-G2 base switches do not ship with fan trays —these must be ordered separately. The X450-G2 PoE switches support modular power supplies and these must be ordered separately. The non-PoE X450-G2 switches have a fixed internal power supply so a power supply does not need to be ordered separately.SpecificationsPerformance and Scale• Less than 4 microsecond latency (64-byte)• Layer 2/MAC Addresses: 68K • IPv4 LPM Entries: 16K• IPv6 LPM (64-bit) Entries: 8K • IPv6 LPM (128-bit) Entries: 256• 4094 VLAN/VMANs• 9216 Byte Max Packet Size (Jumbo Frame)• 128 load sharing trunks, up to 32 members per trunk • 1,024 ingress bandwidth meters•Ingress and egress bandwidth policing/rate limiting per flow/ACL• 8 QoS egress queues/port• Egress bandwidth rate shaping per egress queue andper port*Includes stacking ports.• Rate Limiting Granularity: 8 Kbps• All ports Full Duplex - half duplex operation is not supported• Policy Capabilities • Policy Profiles: 63• Rules per Profile: Up to 1464• Authenticated Policy Users per Switch: Up to 6,144• Authenticated Policy Users per Port: Up to 6,144• Unique Permit/Deny Rules per switch: 1464• MAC Rules: 512• IPv4 Rules: 1280• IPv6 Rules: 256• L2 Rules: 184• Rate Limiting: Per Class of ServiceNOTE: Policy and rule limits here reflect support available in EXOS 22.4.External PortsPhysicalNOTE: Switch weights include installed fan module. PoE switches do not include PSUs.* Please refer to the Summit Family Switches Hardware Installation Guide for packaged weight and dimensions.LED Indicators• Per port status LED including power status • System Status LEDs: management, fan and power • 7 segment display of stack numberPowerThe Non-PoE SwitchesCPU/Memory• 64-bit MIPS Processor, 1 GHz clock, dual core • 1GB ECC DDR3 DRAM • 4GB eMMC Flash • 4MB packet bufferPoE Power Supply Units (Only Front-to-Back Supplies Are Supported)† - The power supplies will continue to operate +- 10% of the rated input to accommodate temporary loss of input voltage regulationPoE-Plus Power BudgetEnvironmental Specifications• EN/ETSI 300 019-2-1 v2.1.2 - Class 1.2 Storage • EN/ETSI 300 019-2-2 v2.1.2 - Class 2.3 Transportation • EN/ETSI 300 019-2-3 v2.1.2 - Class 3.1e Operational • EN/ETSI 300 753 (1997-10) - Acoustic Noise • ASTM D3580 Random Vibration Unpackaged 1.5 GEnvironmental Compliance• EU RoHS: 2011/65/EU • EU WEEE: 2012/19/EU • China RoHS: SJ/T 11363-2006• T aiwan RoHS: CNS 15663 (2013.7)Operating Conditions• T emp: 0° C to 50° C (32° F to 122° F)• Humidity: 10% to 95% relative humidity, non-condensing • Altitude: 0 to 5,000 meters (16,404 feet) – PoE switches• Altitude: 0 to 2,000 meters (6,562 feet) – non- PoE switches• Shock (half sine): 30 m/s2 (3 G), 11 ms, 6 shocks • Random vibration: 3 to 500 Hz at 1.5 G rmsPackaging and Storing Specifications• T emp: -40° C to 70° C (-40° F to 158° F)• Humidity: 10% to 95% relative humidity, non-condensing • Packaged Shock (half sine): 180 m/s2 (18 G), 6 ms, 600 shocks• Packaged Vibration: 5 to 62 Hz at velocity 5 mm/s, 62 to 500 Hz at 0.2 G• Packaged Random Vibration: 5 to 20 Hz at 1.0 ASD w/–3 dB/oct. from 20 to 200 Hz• Packaged Drop Height: 14 drops minimum on sides and corners at 42 inches (<15 kg box)Regulatory and Safety• North American ITE• UL 60950-1 2nd edition A2:2014, Listed Device (U.S.)• CSA 22.2 No. 60950-1 2nd edition 2014 (Canada)• EN 60825-1:2007/IEC 60825-1:2007 Class 1(Lasers Safety)• CDRH Letter of Approval (US FDA Approval)• European ITE• EN 60950-1:2006+A11:2009+A1:2010+A12:2011+A2:2013 2nd Ed.• EN 60825-1:2007/IEC 60825-1:2007 Class 1(Lasers Safety)• 2014/35/EU Low Voltage Directive• International ITE• CB Report & Certificate per IEC 60950-1 :2005+A1:2009+A2:2013 + National Differences• AS/NZS 60950-1 (Australia /New Zealand)EMI/EMC Standards• North American EMC for ITE• FCC CFR 47 part 15 Class A (USA)• ICES-003 Class A (Canada)• European EMC Standards• EN 55032: 2015 Class A• EN 55024: 2010• EN 61000-3-2: 2014 (Harmonics)• EN 61000-3-3: 2013 (Flicker)• EN 300 386 v1.6.1 (EMC T elecommunications)• 2014/30/EU EMC Directive• International EMC Certifications• CISPR 32:2015, Class A (International Emissions)• AS/NZS CISPR32: 2015• CISPR 24:2010 Class A (International Immunity)• IEC 61000-4-2:2008/EN 61000-4-2:2009Electrostatic Discharge, 8kV Contact, 15 kV Air,Criteria B• IEC 61000-4-3:2010/EN 61000-4-3:2006 +A1:2008+A2:2010 Radiated Immunity 10V/m, Criteria A• IEC 61000-4-4:2012. / EN 61000-4-4:2012 Transient Burst, 1 kV, Criteria A• IEC 61000-4-5:2014 /EN 61000-4-5:2014 Surge, 1 kV L-L, 2 kV L-G, Level 3, Criteria B• IEC 61000-4-6:2013/EN 61000-4-6:2014 ConductedImmunity, 0.15-80 MHz, 10Vrms, 80%AM (1kHz)Criteria A• IEC/EN 61000-4-11:2004 Power Dips & Interruptions, >30%, 25 periods, Criteria CCountry Specific• VCCI Class A (Japan Emissions)• ACMA RCM (Australia Emissions)• CCC Mark• KCC Mark, EMC Approval (Korea)Telecom Standards• CE 2.0 CompliantIEEE 802.3 Media Access Standards • IEEE 802.3ab 1000BASE-T• IEEE 802.3z 1000BASE-X• IEEE 802.3ae 10GBASE-X• IEEE 802.3at PoE Plus• IEEE 802.3az (EEE)Fan and Acoustic Noise* Sound Pressure is presented for comparison per ISO 7779**Declared Sound Power is presented in accordance with ISO-7779, ISO 9296 per ETSI/EN 300 753AccessoriesModular Fan Tray for All x450-G2 Switches• X460/X450-G2 fan module FB• Front-to-back airflow fan module for X460/X450-G2 series switchesExternal Redundant Power Supplies forNon-PoE SwitchesAll X450-G2 series non-PoE switches ship with one fixed internal power supply. If redundancy is required, an external RPS can be attached to the switch.Modular Power Supplies for PoE X450-2 Switches• STK-RPS-150PS• 150 watt non-PoE redundant power supply for X450-G2 switches• EPS-C2• External Power System Chassis 2. Accepts up to three 750W AC PoE PSU 48V power supplies.Accepts up to 5 EPS-CBL-2x7 or up to 1 EPS-CBL-2x9 cables.• EPS-CBL-2x7• External Power System Cable (1M) that connects EPS to any X440 or X450-G2 non-PoE switch forproviding redundant DC power.• 750W AC PSU• AC Power Supply module for EPS-C2 Chassis Redundant Power SupplyThe STK-RPS-150PS can be rack mounted into the two slotRPS chassis STK-RPS-150CH2 where the power supplies are horizontally mounted or the eight slot RPS chassis STK-RPS-150CH8 where the power supplies are vertically mounted.All X450-G2 series PoE switches support modular power supplies and do NOT ship with a power supply. Either a 715 watt or 1100 watt power supply needs to be added.Only front-to-back power supplies and fans are certified for use in the X450-G2 PoE switches.• 715W PoE AC PSU FB• 715W PoE AC PSU with front-to-back airflow is compatible with X450-G2-24p/48p switches andprovides 500 watts of PoE-plus power budget perone supply. When two PSUs are installed, the totalPoE-plus power budget becomes 1031 watts.• 1100W PoE AC PSU FB• 1100W PoE AC PSU with front-to-back airflow is compatible with X450-G2-24p/48p switches andprovides 850 watts of PoE-plus power budget perone supply. When two PSUs are installed, the totalPoE-plus power budget becomes 1440 watts.*Optional: Redundant or Additive Power Supply ordered separately**Required: First Power Supply ordered separatelyOrdered EmptyShipped EmptyOrdered Empty Shipped Empty*Ordering InformationOrdering Information (cont.)/contact Phone +1-408-579-2800 ©2017 Extreme Networks, Inc. All rights reserved. Extreme Networks and the Extreme Networks logo are trademarks or registered trademarks of Extreme Networks, Inc. in the United States and/or other countries. All other names are the property of their respective owners. For additional information on Extreme Networks Trademarks please see /company/legal/trademarks. Specifications and product availability are subject to change without notice. 9718-1217-1911Ordering Information (cont.)NOTE: PoE Power Supplies and fan tray MUST be ordered separately. Only non-PoE switches ships with a fixed internal power supply1 1Gb Mode Only2 Supported configuration is to populate every other SFP+ port in system, with a maximum of half the 10Gb SFP+ ports configured with 10GBASE-T transceivers. An adjacent SFP+ port should remain unused for every 10GBASE-T SFP+ installed.。

peerpresure英文解释

peerpresure英文解释

Peer pressure refers to the influence that peers, individuals of the same age or social group, have on an individual. It can manifest in various forms, including direct pressure, indirect pressure, and self-induced pressure. Peer pressure has been a prevalent phenomenon in society, particularly among adolescents and young adults, and it can have both positive and negative effects on individuals.1. Direct pressureDirect pressure is the most str本人ghtforward form of peer pressure. It occurs when an individual is directly influenced or coerced by their peers to engage in cert本人n behaviors or activities. This can include anything from trying drugs or alcohol to engaging in risky or illegal activities. Direct pressure can be difficult to resist, especially for those who desire acceptance and validation from their peers.2. Indirect pressureIndirect pressure is more subtle and occurs when an individual feels the need to conform to the behaviors and attitudes of their peers in order to be accepted. This can manifest in theform of changing one's appearance, beliefs, or interests to fit in with a cert本人n social group. Indirect pressure can be just as powerful as direct pressure, as individuals may feel the need to conform in order to avoid social exclusion.3. Self-induced pressureSelf-induced pressure occurs when an individual internalizes the expectations and norms of their peer group, leading them to put pressure on themselves to conform. This can stem from a desire to be successful, popular, or accepted within their social circle. Self-induced pressure can be particularly challenging to ovee, as it requires individuals to confront and challenge their own beliefs and attitudes.Peer pressure can have both positive and negative effects on individuals, depending on the nature of the influence and the behaviors involved. Positive peer pressure can encourage individuals to engage in healthy and productive activities, such as participating in sports or pursuing academic success. On the other hand, negative peer pressure can lead to detrimental behaviors, such as substance abuse, delinquency, or risky sexual activity.4. Positive effectsPositive peer pressure can foster a sense of belonging and connection within a social group, leading individuals to engage in activities that promote personal growth and development. For example, peers may encourage one another to pursue academic excellence, participate inmunity service, or adopt healthy lifestyle habits. Positive peer pressure can also contribute to the development of valuable social skills, such as cooperation,munication, and teamwork.5. Negative effectsNegative peer pressure, on the other hand, can have detrimental effects on an individual's well-being and future prospects. It can lead to the experimentation and use of drugs and alcohol, participation in criminal activities, or engagement in unsafe sexual behaviors. Negative peer pressure can also contribute to the development of low self-esteem, feelings of isolation, and mental health issues. In extreme cases, it can even result in long-term negative consequences, such as addiction, legal trouble, or academic f本人lure.6. Strategies for coping with peer pressureCoping with peer pressure can be challenging, but there are strategies that individuals can use to resist negative influences and make positive choices. One approach is to develop a strong sense of self-confidence and self-assertion, allowing individuals to stand up for their values and beliefs in the face of peer pressure. Building a supportive network of friends and family members can also provide individuals with the encouragement and validation they need to resist negative influences.7. Additionally, developing strong decision-making and critical thinking skills can help individuals evaluate the potential consequences of their actions and make informed choices. Learning to assert oneself andmunicate effectively can also enable individuals to express their boundaries and resist unwanted pressure from their peers. Finally, seeking guidance from trusted adults, such as parents, teachers, or mentors, can provide individuals with valuable insight and support in navigating peer pressure situations.In conclusion, peer pressure is a pervasive influence that canhave both positive and negative effects on individuals. It can manifest in various forms, including direct pressure, indirect pressure, and self-induced pressure, and can lead to a range of behaviors and oues. By developing strong self-confidence, assertiveness, and decision-making skills, individuals can resist negative peer pressure and make positive choices that contribute to their personal growth and well-being.。

辱虐管理研究的_特征_过程_结果_理论框架_李爱梅

辱虐管理研究的_特征_过程_结果_理论框架_李爱梅

心理科学进展 2013, Vol. 21, No. 11, 1901–1912 Advances in Psychological ScienceDOI: 10.3724/SP.J.1042.2013.019011901·主编特邀 (Editor-In-Chief Invited·辱虐管理研究的“ 特征 -过程 -结果” 理论框架 *李爱梅华涛高文(暨南大学管理学院 , 广州 510632摘要近年来 , 辱虐管理成为领导行为研究的重要主题 , 它是指下属对领导持续表现出的言语或非言语敌意行为的感知。

一方面 , 主管特征、下属特征、上下级关系特征和环境特征是影响辱虐管理的重要前因变量 ; 另一方面 , 辱虐管理也会导致自我导向的、组织导向的和人际导向的负性结果以及溢出效应等。

其中认知因素与情绪因素的交互作用是辱虐管理产生负性后果的心理机制。

未来研究应进一步探讨各特征变量的交互作用及对辱虐管理的影响 , 开展组织中辱虐管理的跨层次和两面性研究 , 考察中国情境下辱虐管理的实践后果及作用机制。

关键词辱虐管理 ; 组织公民行为 ; 情绪耗竭 ; 溢出效应分类号B849:C931 引言传统的领导理论大都研究建设性的、有效的和成功的领导 , 很少关注负性的、破坏性的领导行为及其对组织和成员可能产生的消极影响。

随着安然公司等国际大企业的弊案频频发生 , 2007年第 18期《领导季刊》 (Leadership Quarterly把“ 破坏性领导” 作为研究专题 , 人们对负性领导的破坏性给予了关注 (领导季刊 ,2007。

不同的研究者根据研究侧重点提出了不同的概念 , 如暴君行为 (petty tyranny (Ashforth, 1994, 欺凌 (bullying (Einarsen, 1999, 主管损害 (supervisor undermining (Duffy, Ganster, & Pagon, 2002, 毒性领导 (toxic leadership (Lipman-Blumen, 2006, 主管侵犯 (supervisor aggression (Schat, Frone, & Kelloway, 2006, 破坏性领导(destructive leadership (Einarsen, Aasland, & Skogstad, 2007, 但是大部分研究者都使用了辱虐管理 (abusive supervision (Tepper, 2000 这一概念。

高等学校英语应用能力考试A级模拟试卷1(附答案)

高等学校英语应用能力考试A级模拟试卷1(附答案)

高等学校英语应用能力考试A级真题模拟卷1Part I Listening Comprehension (15minutes)Directions：This part is to test your listening ability。

It consists of 3 sections。

Section ADirections：This section is to test your ability to understand short dialogues。

There are 5 recorded dialogues in it. After each dialogue, there is a recorded question。

Thedialogues and questions will be spoken only once. When you hear a question，youshould decide on the correct answer from the 4 choices marked A)，B），C）and D）given in your test paper。

Then you should mark the corresponding letter on theAnswer Sheet with a single line through the center.1. A。

She met with traffic jam。

B。

The road was wet。

C. Her car was broken。

D。

She forgot the time.2。

A。

During dinner。

B. Before dinner。

C. Right after dinner. D。

Tomorrow.3。

A。

Nothing. B. Hot coffee。

C。

Ice cream。

D. Tea.4。

导入设备介绍 导入保护REG615标准配置A说明书

导入设备介绍 导入保护REG615标准配置A说明书

—G U I DEFO R M S PECI FI C ATI ONInterconnection Protection REG615std configuration ANumerical interconnection protectionin medium-voltage networksThe relay is intended for protection, control, measurement and supervision of interconnection points of distributed generation units in utility and industrial power distribution systems.Mechanical and construction details• The relay shall have compact dimensions not exceeding 4U in height. The depth of the relay shall, without any additional raising frame, not exceed 160 mm when flush mounted so as not to foul with other equipment mounted inside the cabinet.• The weight of the relay must not exceed 5 kgs to permit use of optimized sheet metal thickness in construction of panels.• The relay shall support flush, semi-flush, rack and wall mounting options.• As flush mounted, the relay shall meet the IP54 ingress protect ion requirements on the front side and IP20 on the rear side and connection terminals.• To facilitate quick unit replacement, the relay design shall be of draw-out type with secure current transformer (CT) shorting . It shall be possible to quickly replace a faulty unit with a less than 30 minutes.• To prevent unauthorized detachment of the relay plug-in unit, the relay shall be provided with an integrated seal.• The relay shall have a graphical display with at least 7 rows of characters and up to 20 characters per row.Protection functionsDistributed Power Generation Units (DPGU):• In distributed power generation applications where the power generation units (PGU) are connected to the grid, the PGUs are required to comply with grid connection requirements (grid codes) including system stability, reactive power support, transient recovery and voltage-frequency regulations. The grid codes require the distributed PGUs to remain connected even during network disturbances to ensure grid stability and reliability and thus avoiding a grid collapse. To enable the connection of distributed power generation units to the grid the relay shall include the following protection functions:-To determine whether and when to disconnect a distributed generation unit from the grid during network disturbances, the relay shall have three-stage low-voltage ride-through protection 27RT) with a user-definable Low-Voltage Ride-Through (LVRT) curve, to comply with local or national grid cod e requirements.-To ensure power system stability, the relay shall have directional reactive power and undervoltage protection (32Q,27) and monitor the reactive power flow to prevent a power system voltage collapse in the event of a network fault.-To detect islanding or loss-of-mains conditions of distributed generation units, the relay shall have vector shift protection (78V). The function shall continuously measure the voltage cycle shift in terms of the phase angle, which shall be settable between 2 and 30 degrees with 1 degree resolution.-The relay shall support the combined and parallel use of multiple protection functions to detect loss-of-mains conditions. The relay shall to minimize the non-detectable zone , support the combination of vector shift protection (78V) and frequency rate-of-change protection (81R), or other user-definable combinations of passive detecting techniques such as overvoltage, undervoltage, overfrequency, underfrequency, rate-of-change of frequency and voltage unbalance.-The relay must have three-stage frequency protection, including at least overfrequency (81O), underfrequency (81U) and frequency rate-of-change (81R) protection with rate-of-rise or rate-of-fall freely selectable for each stage.2 Other protection functions:• The relay shall have non-directional overcurrent(50) and earth -fault (50N) protection.• The relay shall have three-stage directionalovercurrent and earth-fault protection (67/67N)with voltage memory and positive and negative-sequence voltage polarization. I0 and Ushall bederived either from the phase voltages and currents or from the measured neutral current and residual voltage.• In compensated, unearthed and high-resistance earthed networks, the relay shall be able to detect transient, intermittent and continuous earth faults.• The relay shall have two-stage negative-sequence overcurrent protection (46) settable between 0.01and 5 times In , definite time (DT) and inversedefinite minimum time (IDMT) characteristics, supporting both IEC and ANSI/IEEE operating curves.• The relay shall have comprehensive voltage protection functionality, including at least overvoltage (59), undervoltage (27), positive-sequence undervoltage (47U+), negative-sequence overvoltage(47O-) and residual overvoltage (59G) protection with multiple stages.• The relay shall have three-phase thermal overload protection (49F).• The relay shall have a three-phase inrush detector (68) to avoid tripping during magnetizing inrush conditions. It shall be possible to selectively block the overcurrent and earth-fault protection stages when the ratio of the 2nd harmonic component to the fundamental component exceeds the set value.• To protect the generator and turbine from the harmful effect of excessive power/motoring, the relay shall have two stage reverse power/ directional overpower protection (32R/32O). It shall be possible to use positive-sequence components for calculating power, which makes the determination of power insensitive to the possible asymmetry in currents or voltages and corresponds to the real load of the generator’s prime mover . The protection function shall have a settable power angle between -90 to +90 degrees and an adjustable power setting range of 1 % to 200 %.• The relay shall have circuit breaker failure protection (51BF/5 1NBF) including independent timers for repeated tripping of the same breaker and backup tripping of the upstream breaker. The function shall allow higher selectivity by avoiding tripping of the upstream breaker if the repeated tripping of the breaker closest to the fault is successful.• The relay shall have arc protection based on simultaneous detection of current and light. During maintenance work at the substation, it shall be possible to change the operation criteria to light only via a binary input.Inputs and outputs• The relay shall have 12 binary inputs and 9 binary outputs and all of them freely configurable. Optionally, it must be possible to add 4 more binary inputs and 1 more binary output.• To enable direct tripping of the circuit breaker, the relay must have 2 double-pole power output relays with integrated trip-circuit supervision (TCS). The two power output relays shall be rated to make and carry 30 A for 0.5 s with a breaking capacity of ≥1 A (L/R<40 ms).• To enable fast direct tripping of the circuit breaker, the relay must have 3 optional high-speed binary outputs with an operate time of ≤ 1 ms. The binary output contacts shall be rated to make and carry 30 A for 0.5 s with a breaking capacity of ≥1 A(L/R<40 ms).• The threshold voltage of the relay’s binary inputs shall be set table to 16...176 V DC.• The relay shall be equipped with inputs for detecting temperature using resistance temperature detector (RTD) sensors. At least 2 inputs shall be required. It shall be possible to include the ambient temperature measured from an external temperature sensor in thermal modeling of the three-phase thermal protection for feeders.• The relay shall support the commonly used sensor types Pt100, Pt250 ,Ni100, Ni120, Ni250 and Cu10 with 2-wire or 3-wire connection with common ground.• The phase current inputs and the residual current input of the relay shall be rated 1/5 A. The selection of 1 A or 5 A shall be software based.• For applications requiring sensitive earth fault protection the relay shall offer an optional 0.2/1 A residual current input. The selection of 0.2 A or 1 A shall be software based.3Measurements, alarms and reporting• The relay shall have three-phase current and voltage measurement (fundamental or RMS-based as selectable options) with an accuracy of ±0.5% and zero, negative and positive-sequence current and voltage measurement functionality with an accuracy of ±1% within the range of ±2Hz of the nominal frequency.• To collect sequence-of-events (SoE) information, the relay must include a non-volatile memory with a capacity of storing at least 1024 event codes with associated time stamps.• The relay must support the storage of at least 128 fault records in the relay’s non-volatile memory.• The fault record values must at least include phase currents, phase voltages, zero, negative and positive-sequence currents and voltages, and the active setting group.• The relay shall have a disturbance recorder supporting a sampling frequency of 32 samples per cycle and featuring up to 12 analog and 64 binary signal channels.• The relay’s disturbance recorder shall support not less than 6 three-second recordings at 32 samples per cycle for 12 analog channels and 64 binary channels.• The relay shall support up to 100 disturbance recordings.• The relay must have a load profile recorder for phase currents and voltages supporting up to 12 selectable load quantities and more than 1 year of recording length. The load profile recorder output shall be in COMTRADE format.• The relay shall include a motor runtime counter for calculating and presenting the accumulated operation time of a machine. The function shall alert the operator via a warning and an alarm when the accumulated operation time exceeds the set munication• The relay must support IEC 61850 Edition 1 and Edition 2.• The relay must support, besides IEC 61850, simultaneous communication using one of the following communication protocols: Modbus® (RTU-ASCII/TCP), IEC 60870-5-103 orDNP3 (serial/TCP).• The relay must have an Ethernet port (RJ45) on the front for local parametrization and data retrieval.• The relay shall support up to five IEC 61850 (MMS) clients simultaneously.• The relay must have two fiber-optic Ethernet ports with HSR and PRP-1.• The relay shall have a third Ethernet port for providing connectivity of any other Ethernet device to an IEC 61850 station bus inside a switchgear bay.• The relay must support IEC 61850 GOOSE messaging and meet the performance requirements for tripping applications (<10 ms) as defined by the IEC 61850 standard.• The relay shall have support for sharing analog values like temperature, resistance, tap positions using IEC 61850 GOOSE messaging.• The relay must support IEEE 1588 v2 for high-accuracy time synchronization (< 4 μs) in Ethernet-based applications. The relay shall also support the SNTP (Simple Network Time Protocol ) and IRIG-B (Inter-Range Instrumentation Group - Time Code Format B) time synchronization methods.• The relay must support IEC 61850-9-2LE with IEEE 1588 v2 for accurate time synchronization.Engineering and configurability• The relay must have 6 independent settings groups for the relevant protection settings (start value, operate time). It must be possible to change protection setting values from one setting group to another in less than 20 ms from the binary input activation.• The relay must have a web browser-based human-machine interface (WHMI) with secured communication (TLS) and shall provide the following functions:-Programmable LEDs and event lists-System supervision-Parameter settings-Measurement display-Disturbance records-Phasor diagram-Single-line diagram (SLD)-Importing and exporting of parameters• When a protection function is disabled or removed from the configuration, neither the relay nor the programming tool shall show the function-related settings.• The relay HMI and engineering tool shall have multilingual support.• The relay HMI and engineering tool shall support IEC and ANSI protection function codes.• The relay shall have at least 11 freely configurable and programmable two-color LEDs.• The relay must have at least 10 user-configurable local HMI views including measurements and SLDs.• The relay shall have a graphical configuration tool for the complete relay application including multi-level logic programming support, timers and flip-flops.• The relay configuration tool must include online visualization of the relay application state.• It must be possible to keep the relay configuration tool up-to- date using an online update functionality.• The relay configuration tool shall support viewing of relay events, fault records and visualization of disturbance recordings.• The relay configuration tool must include the complete relay documentation including operation and technical details.• The relay configuration tool must include functionality for comparing the archived configuration to the configuration in the relay.• The relay configuration tool must allow configuration of IEC 61850 vertical and horizontal communication including GOOSE and sampled values.• The relay configuration tool must supportimporting and exporting of valid IEC 61850 files (ICD, CID, SCD, IID).• The relay configuration tool must be compatiblewith earlier relay versions.Type tests and other compliance requirements• The relay shall have an operational temperaturerange of -25 … +55°C and transport/storage temperature range of -40...+85°C.• The relay must fulfill the mechanical test requirements according to IEC 60255-21-1, -2 and-3, Class 2 for vibration, shock, bump and seismic compliance.• The relay’s maximum DC auxiliary power consumption shall be less than 20 W (all inputs activated and over the full supply range).• The relay must have an IEC 61850 Edition 2certificate from an accredited Level A testing laboratory.• The relay must fulfill the electromagnetic compatibility (EMC) test requirements accordingto IEC 60255-26.• The relay must be tested according to the requirements of the IEC or an equivalent standard. Additional informationFor more information, please contact your local ABB representative or visit our website at:/substationautomation/mediumvoltage1MRS758551B©Copyright218ABB.Allrightsreserved.—The information in this document is subject to change without notice and should not be construed as a commitment by ABB. ABB assumes no responsibility for any errors that may appear in this document. ABB is a registered trademark of the ABB Group. All other brand or product names mentioned in this document may be trademarks or registered trademarks of their respective holders.—/mediumvoltage。

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1 2 3 4 5
Goal
Protocol
Environment
Experiments
Conclusions 6
HOTP2P 2010, April 23, 2010.
2. Self-adaptive protocol (cont’d)
Cactus is an event based framework:
Our modifications to Cactus → improve protocol performance/facilitate reconfiguration:
Concurrent handler execution (multicore machines). Eliminate unnecessary copies between layers (use pointers) Operation for micro-protocol removing.
File sharing, video, ... Recent advances in microprocessor architecture and high bandwith network → new applications like distributed HPC computing/computing on the Internet.
Great challenges
Scalability, Heterogeneity, Volatility, Existing protocols, TCP, UDP not well suited to HPC.
1 2 3 4 5
Goal
Protocol
Environment
Micro-protocols implement a functionnality (sample)
Communication: Synchronous, Asynchronous. Fragmentation: FixeSize, Resize. Reliability: Retransmission, PositiveAck, NegativeAck, DuplicateAck. Order : LossyFifo, ReliableFifo. Congestion control: NewReno TCP Congestion Control.
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Goal
Protocol
Environment
Experiments
Conclusions 7
HOTP2P 2010, April 23, 2010.
2. Self-adaptive protocol (cont’d)
P2PSAP protocol architecture
Manages session opening an closure Captures context information Reconfigures data channel/coordinates peers API ~~~~~~~~~~~ Transfers data between peers Transport layer
HOTP2P 2010, April 23, 2010.
2. Self-adaptive protocol (cont’d)
Protocol composition framework → deployment of architecture
Hierarchical model (stack of protocols), x-kernel, APPIA frameworks. Nonhierarchical model (no order), Coyote and ADAPTIVE frame’ks. Hybrid model (combo), XQoS and Cactus frameworks → CTP.
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Goal
Protocol
Environment
Experiments
Conclusions 11
HOTP2P 2010, April 23, 2010.
3. Environment
Direct communication between peers Reduced set of communication operations: - only send and receive operations (P2P_send and P2P_receive).
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Goal
Protocol
Environment
Experiments
Conclusions 4
HOTP2P 2010, April 23, 2010.
2. Self-adaptive protocol
Micro-protocols
Introduced in x-kernel Approach to design self-adaptive communication protocols
Composition of micro-protocols → protocol
Reuse code, facilitate design, configure dynamically.
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Goal
Protocol
Environment
Experiments
Conclusions 5
~~~~~~~~~~~ Physical layer
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Goal
Protocol
Environment
Experiments
Conclusions 8
HOTP2P 2010, April 23, 2010.
2. Self-adaptive protocol (cont’d)
Communication adaptation rules
Reconfiguration mechanism
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Goal
Protocol
Environment
Experiments
Conclusions 10
HOTP2P 2010, April 23, 2010.
2. Self-adaptive protocol (cont’d)
Example of scenario
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Goal
Protocol
Environment
Experiments
Conclusions 12
HOTP2P 2010, April 23, 2010.
3. Environment (cont’d)
P2PDC Environment architecture
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Goal
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Asynchronous Unreliable Com.
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Asynchronous Unreliable Com.
4 5
Goal
Protocol
Environment
Experiments
Conclusions 9
HOTP2P 2010, April 23, 2010.
2. Self-adaptive protocol (cont’d)
High performance Peer to Peer Distributed Computing with Application to Obstacle Problem
D. EL BAZ (LAAS-CNRS, Toulouse France) Coauthors : T. T. NGUYEN, P. SPITERI, G. JOURJON, M. CHAU funded by
Events: state changes, e.g. arrival of messages.
Micro-protocols structured as a collection of event handlers:
Event handler : procedure like segments of codes bound to events. When an event occurs all handlers bound to that event are executed.
Self-adaptive protocol:
based on Cactus framework uses micro-protocols chooses dynamicaly the most appropriate communication mode in function of elements of context from network level and choices at application level.
Experiments
Conclusions 3
HOTP2P 2010, April 23, 2010.
1. Goal (cont’d)
High performance peer to peer computing:
Task parallel model, distributed iterative methods. Direct communications between peers. Applications: numerical simulation & optimization.
HOTP2P 2010, April 23, 2010.
Outline
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