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EN55022-2006

认证之家 EUROPEAN STANDARDEN 55022 NORME EUROPÉENNEEUROPÄISCHE NORM September 2006CENELECEuropean Committee for Electrotechnical StandardizationComité Européen de Normalisation ElectrotechniqueEuropäisches Komitee für Elektrotechnische NormungCentral Secretariat: rue de Stassart 35, B - 1050 Brussels© 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.Ref. No. EN 55022:2006 E ICS 33.100.10Supersedes EN 55022:1998 + A1:2000 + A2:2003English versionInformation technology equipment -Radio disturbance characteristics -Limits and methods of measurement(CISPR 22:2005, modified)Appareils de traitement de l'information - Caractéristiques des perturbationsradioélectriques -Limites et méthodes de mesure(CISPR 22:2005, modifiée)Einrichtungen der Informationstechnik - Funkstöreigenschaften - Grenzwerte und Messverfahren (CISPR 22:2005, modifiziert)This European Standard was approved by CENELEC on 2005-09-13. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions.CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.EN 55022:2006– 2 –ForewordThe text of the International Standard CISPR 22:2003 as well as A1:2004 and CISPR/I/136/FDIS (Amendment 3) and CISPR/I/128/CDV (Amendment 2, fragment 17), prepared by CISPR SC I "Electromagnetic compatibility of information technology equipment, multimedia equipment and receivers", together with the common modifications prepared by the Technical Committee CENELEC TC 210, Electromagnetic compatibility (EMC), was submitted to the CENELEC Unique Acceptance Procedure for acceptance as a European Standard.In addition, the text of CISPR/I/135A/FDIS (future A2, fragment 1) to CISPR 22:2003, also prepared by CISPR SC I "Electromagnetic compatibility of information technology equipment, multimedia equipment and receivers", was submitted to the CENELEC formal vote as prAD to prEN 55022:2005, with the intention of the two documents being merged and ratified together as a new edition of EN 55022.During the period of voting on these CENELEC drafts, the amendments CISPR/I/135A/FDIS and CISPR/I/136/FDIS (Amendments 2 and 3 respectively) made to CISPR 22:2003, resulted in the publication of a new (fifth) edition of CISPR 22, in accordance with IEC rules. The resulting CISPR 22:2005 was published in April 2005.This resulting version of EN 55022, which was ratified on 2005-09-13, is therefore identical to CISPR 22:2005 except for the common modifications that were included in the document submitted to the CENELEC Unique Acceptance Procedure. The common modifications include CISPR/I/128/CDV, as this draft was not implemented in the unamended CISPR 22:2005.This European Standard supersedes EN 55022:1998 and its amendments A1:2000 and A2:2003.The following dates were fixed:–latest date by which the EN has to be implementedat national level by publication of an identicalnational standard or by endorsement (dop) 2007-04-01–latest date by which the national standards conflictingwith the EN have to be withdrawn (dow) 2009-10-01This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association and covers essential requirements of EC Directives 89/336/EEC, 2004/108/EC and 1999/5/EC. See Annex ZZ.__________– 3 – EN 55022:2006CONTENTS INTRODUCTION (6)1Scope and object (7)2Normative references (7)3Definitions (8)4Classification of ITE (9)4.1Class B ITE (9)4.2Class A ITE (10)5Limits for conducted disturbance at mains terminals and telecommunication ports (10)5.1Limits of mains terminal disturbance voltage (10)5.2Limits of conducted common mode (asymmetric mode) disturbanceat telecommunication ports (11)6Limits for radiated disturbance (11)7Interpretation of CISPR radio disturbance limit (12)7.1Significance of a CISPR limit (12)7.2Application of limits in tests for conformity of equipment in series production (12)8General measurement conditions (13)8.1Ambient noise (13)8.2General arrangement (14)8.3EUT arrangement (16)8.4Operation of the EUT (18)8.5Operation of multifunction equipment (19)9Method of measurement of conducted disturbance at mains terminals and telecommunication ports (20)9.1Measurement detectors (20)9.2Measuring receivers (20)9.3Artificial mains network (AMN) (20)9.4Ground reference plane (21)9.5EUT arrangement (21)9.6Measurement of disturbances at telecommunication ports (23)9.7Recording of measurements (27)10Method of measurement of radiated disturbance (27)10.1Measurement detectors (27)10.2Measuring receivers (27)10.3Antenna (27)10.4Measurement site (28)10.5EUT arrangement (29)10.6Recording of measurements (29)10.7Measurement in the presence of high ambient signals (30)10.8User installation testing (30)11Measurement uncertainty (30)EN 55022:2006– 4 –Annex A (normative) Site attenuation measurements of alternative test sites (41)Annex B (normative) Decision tree for peak detector measurements (47)Annex C (normative) Possible test set-ups for common mode measurements (48)Annex D (informative) Schematic diagrams of examples of impedance stabilization networks (ISN) (55)Annex E (informative) Parameters of signals at telecommunication ports (64)Annex F (informative) Rationale for disturbance measurements and methods (67)Annex ZA (normative) Normative references to international publications with their corresponding European publications (75)Annex ZZ (informative) Coverage of Essential Requirements of EC Directives (76)Bibliography (74)Figure 1 – Test site (31)Figure 2 – Minimum alternative measurement site (32)Figure 3 – Minimum size of metal ground plane (32)Figure 4 – Example test arrangement for tabletop equipment (conducted and radiated emissions) (plan view) (33)Figure 5 – Example test arrangement for tabletop equipment (conducted emission measurement – alternative 1a) (34)Figure 6 – Example test arrangement for tabletop equipment (conducted emission measurement – alternative 1b) (34)Figure 7 – Example test arrangement for tabletop equipment (conducted emission measurement – alternative 2) (35)Figure 8 – Example test arrangement for floor-standing equipment (conductedemission measurement) (36)Figure 9 – Example test arrangement for combinations of equipment (conductedemission measurement) (37)Figure 10 – Example test arrangement for tabletop equipment (radiated emission measurement) (37)Figure 11 – Example test arrangement for floor-standing equipment (radiated emission measurement) (38)Figure 12 – Example test arrangement for floor-standing equipment with vertical riserand overhead cables (radiated and conducted emission measurement) (39)Figure 13 – Example test arrangement for combinations of equipment (radiatedemission measurement) (40)Figure A.1 – Typical antenna positions for alternate site NSA measurements (44)Figure A.2 – Antenna positions for alternate site measurements for minimumrecommended volume (45)Figure B.1 – Decision tree for peak detector measurements (47)Figure C.1 – Using CDNs described in IEC 61000-4-6 as CDN/ISNs (49)Figure C.2 – Using a 150 Ω load to the outside surface of the shield ("in situCDN/ISN") (50)Figure C.3 – Using a combination of current probe and capacitive voltage probe (50)Figure C.4 – Using no shield connection to ground and no ISN (51)Figure C.5 – Calibration fixture (53)Figure C.6 – Flowchart for selecting test method (54)Figure D.1 − ISN for use with unscreened single balanced pairs (55)– 5 – EN 55022:2006 Figure D.2 − ISN with high longitudinal conversion loss (LCL) for use with either oneor two unscreened balanced pairs (56)Figure D.3 − ISN with high longitudinal conversion loss (LCL) for use with one, two,three, or four unscreened balanced pairs (57)Figure D.4 − ISN, including a 50 Ω source matching network at the voltage measuringport, for use with two unscreened balanced pairs (58)Figure D.5 − ISN for use with two unscreened balanced pairs (59)Figure D.6 − ISN, including a 50 Ω source matching network at the voltage measuringport, for use with four unscreened balanced pairs (60)Figure D.7 − ISN for use with four unscreened balanced pairs (61)Figure D.8 − ISN for use with coaxial cables, employing an internal common modechoke created by bifilar winding an insulated centre-conductor wire and an insulatedscreen-conductor wire on a common magnetic core (for example, a ferrite toroid) (61)Figure D.9 − ISN for use with coaxial cables, employing an internal common modechoke created by miniature coaxial cable (miniature semi-rigid solid copper screen or miniature double-braided screen coaxial cable) wound on ferrite toroids (62)Figure D.10 − ISN for use with multi-conductor screened cables, employing an internal common mode choke created by bifilar winding multiple insulated signal wires and an insulated screen-conductor wire on a common magnetic core (for example, a ferrite toroid) (62)Figure D.11 − ISN for use with multi-conductor screened cables, employing an internal common mode choke created by winding a multi-conductor screened cable on ferrite toroids (63)Figure F.1 – Basic circuit for considering the limits with defined TCM impedance of 150 Ω..70 Figure F.2 – Basic circuit for the measurement with unknown TCM impedance (70)Figure F.3 – Impedance layout of the components used in Figure C.2 (72)Figure F.4 – Basic test set-up to measure combined impedance of the 150 Ω and ferrites (73)Table 1 – Limits for conducted disturbance at the mains ports of class A ITE (10)Table 2 – Limits for conducted disturbance at the mains ports of class B ITE (11)Table 3 – Limits of conducted common mode (asymmetric mode) disturbanceat telecommunication ports in the frequency range 0,15 MHz to 30 MHz for class A equipment (11)Table 4 – Limits of conducted common mode (asymmetric mode) disturbance at telecommunication ports in the frequency range 0,15 MHz to 30 MHz for class B equipment (11)Table 5 – Limits for radiated disturbance of class A ITE at a measuring distance of10 m (12)Table 6 – Limits for radiated disturbance of class B ITE at a measuring distance of10 m (12)Table 7 – Acronyms used in figures (31)Table A.1 – Normalized site attenuation (A N (dB)) for recommended geometries with broadband antennas (43)Table F.1 – Summary of advantages and disadvantages of the methods described inAnnex C (68)EN 55022:2006– 6 –INTRODUCTIONThe scope is extended to the whole radio-frequency range from 9 kHz to 400 GHz, but limits are formulated only in restricted frequency bands, which is considered sufficient to reach adequate emission levels to protect radio broadcast and telecommunication services, and to allow other apparatus to operate as intended at reasonable distance.– 7 – EN 55022:2006 INFORMATION TECHNOLOGY EQUIPMENT –RADIO DISTURBANCE CHARACTERISTICS –LIMITS AND METHODS OF MEASUREMENT1 Scope and objectThis International Standard applies to ITE as defined in 3.1.Procedures are given for the measurement of the levels of spurious signals generated by the ITE and limits are specified for the frequency range 9 kHz to 400 GHz for both class A and class B equipment. No measurements need be performed at frequencies where no limits are specified.The intention of this publication is to establish uniform requirements for the radio disturbance level of the equipment contained in the scope, to fix limits of disturbance, to describe methods of measurement and to standardize operating conditions and interpretation of results.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.IEC 60083:1997, Plugs and socket-outlets for domestic and similar general use standardized in member countries of IECIEC 61000-4-6:2003, Electromagnetic compatibility (EMC) – Part 4-6: Testing and measurement techniques – Immunity to conducted disturbances, induced by radio-frequency fieldsCISPR 11:2003, Industrial, scientific, and medical (ISM) radio-frequency equipment – Electro-magnetic disturbance characteristics – Limits and methods of measurementCISPR 13:2001, Sound and television broadcast receivers and associated equipment – Radio disturbance characteristics – Limits and methods of measurementCISPR 16-1-1:2003, Specification for radio disturbance and immunity measuring apparatus and methods – Part 1-1: Radio disturbance and immunity measuring apparatus – Measuring apparatusCISPR 16-1-2:2003, Specification for radio disturbance and immunity measuring apparatus and methods – Part 1-2: Radio disturbance and immunity measuring apparatus – Ancillary equipment – Conducted disturbances 1Amendment 1 (2004)___________1There exists a consolidated edition 1.1 (2004) including edition 1.0 and its Amendment 1.EN 55022:2006– 8 –CISPR 16-1-4:2004, Specification for radio disturbance and immunity measuring apparatus and methods – Part 1-4: Radio disturbance and immunity measuring apparatus – Ancillary equipment – Radiated disturbancesCISPR 16-4-2:2003, Specification for radio disturbance and immunity measuring apparatus and methods – Part 4-2: Uncertainties, statistics and limit modelling – Uncertainty in EMC measurements3 DefinitionsFor the purposes of this document the following definitions apply:3.1information technology equipment (ITE)any equipment:a) which has a primary function of either (or a combination of) entry, storage, display,retrieval, transmission, processing, switching, or control, of data and of telecommuni-cation messages and which may be equipped with one or more terminal ports typically operated for information transfer;b) with a rated supply voltage not exceeding 600 V.It includes, for example, data processing equipment, office machines, electronic business equipment and telecommunication equipment.Any equipment (or part of the ITE equipment) which has a primary function of radio trans-mission and/or reception according to the ITU Radio Regulations are excluded from the scope of this publication.NOTE Any equipment which has a function of radio transmission and/or reception according to the definitions of the ITU Radio Regulations should fulfil the national radio regulations, whether or not this publication is also valid. Equipment, for which all disturbance requirements in the frequency range are explicitly formulated in other IEC or CISPR publications, are excluded from the scope of this publication.3.2equipment under test (EUT)representative ITE or functionally interactive group of ITE (system) which includes one or more host unit(s) and is used for evaluation purposes3.3host unitpart of an ITE system or unit that provides the mechanical housing for modules, which may contain radio-frequency sources, and may provide power distribution to other ITE. Power distribution may be a.c., d.c., or both between the host unit(s) and modules or other ITE3.4modulepart of an ITE which provides a function and may contain radio-frequency sources3.5identical modules and ITEmodules and ITE produced in quantity and within normal manufacturing tolerances to a given manufacturing specification– 9 – EN 55022:20063.6telecommunications/network portpoint of connection for voice, data and signalling transfers intended to interconnect widely-dispersed systems via such means as direct connection to multi-user telecommunications networks (e.g. public switched telecommunications networks (PSTN) integrated services digital networks (ISDN), x-type digital subscriber lines (xDSL), etc.), local area networks (e.g. Ethernet, Token Ring, etc.) and similar networksNOTE A port generally intended for interconnection of components of an ITE system under test (e.g. RS-232, IEEE Standard 1284 (parallel printer), Universal Serial Bus (USB), IEEE Standard 1394 (“Fire Wire”), etc.) and used in accordance with its functional specifications (e.g. for the maximum length of cable connected to it), is not considered to be a telecommunications/network port under this definition.3.7multifunction equipmentinformation technology equipment in which two or more functions subject to this standard and/or to other standards are provided in the same unitNOTE Examples of information technology equipment include–a personal computer provided with a telecommunication function and/or broadcast reception function; – a personal computer provided with a measuring function, etc.3.8total common mode impedanceTCM impedanceimpedance between the cable attached to the EUT port under test and the reference ground planeNOTE The complete cable is seen as one wire of the circuit, the ground plane as the other wire of the circuit. The TCM wave is the transmission mode of electrical energy, which can lead to radiation of electrical energy if the cable is exposed in the real application. Vice versa, this is also the dominant mode, which results from exposition of the cable to external electromagnetic fields.3.9arrangementphysical layout of the EUT that includes connected peripherals/associated equipment within the test area3.10configurationmode of operation and other operational conditions of the EUT3.11associated equipmentAEequipment needed to maintain the data traffic on the cable attached to the EUT port under test and (or) to maintain the normal operation of the EUT during the test. The associated equipment may be physically located outside the test areaNOTE The AE can be another ITE, a traffic simulator or a connection to a network. The AE can be situated close to the measurement set-up, outside the measurement room or be represented by the connection to a network. AE should not have any appreciable influence on the test results.4 Classification of ITE4.1 Class B ITEClass B ITE is a category of apparatus which satisfies the class B ITE disturbance limits. ITE is subdivided into two categories denoted class A ITE and class B ITE.EN 55022:2006 – 10 – Class B ITE is intended primarily for use in the domestic environment and may include:– equipment with no fixed place of use; for example, portable equipment powered by built-inbatteries;– telecommunication terminal equipment powered by a telecommunication network; – personal computers and auxiliary connected equipment.NOTE The domestic environment is an environment where the use of broadcast radio and television receivers may be expected within a distance of 10 m of the apparatus concerned.4.2 Class A ITE WarningThis is a class A product. In a domestic environment this product may cause radio inter-ference in which case the user may be required to take adequate measures.5 Limits for conducted disturbance at mains terminalsand telecommunication portsThe equipment under test (EUT) shall meet the limits in Tables 1 and 3 or 2 and 4, as appli-cable, including the average limit and the quasi-peak limit when using, respectively, an average detector receiver and quasi-peak detector receiver and measured in accordance with the methods described in Clause 9. Either the voltage limits or the current limits in Table 3 or 4, as applicable, shall be met except for the measurement method of C.1.3 where both limits shall be met. If the average limit is met when using a quasi-peak detector receiver, the EUT shall be deemed to meet both limits and measurement with the average detector receiver is unnecessary.If the reading of the measuring receiver shows fluctuations close to the limit, the reading shall be observed for at least 15 s at each measurement frequency; the higher reading shall be recorded with the exception of any brief isolated high reading which shall be ignored.5.1 Limits of mains terminal disturbance voltageTable 1 – Limits for conducted disturbance at the mains portsof class A ITE Limits dB(μV) Frequency rangeMHzQuasi-peak Average 0,15 to 0,5079 66 0,50 to 30 73 60NOTE The lower limit shall apply at the transition frequency.Class A ITE is a category of all other ITE which satisfies the class A ITE limits but not the class B ITE limits. The following warning shall be included in the instructions for use:Table 2 – Limits for conducted disturbance at the mains portsof class B ITE Limits dB(μV) Frequency rangeMHzQuasi-peak Average 0,15 to 0,5066 to 56 56 to 46 0,50 to 556 46 5 to 30 60 50NOTE 1 The lower limit shall apply at the transition frequencies.NOTE 2 The limit decreases linearly with the logarithm of the frequency in therange 0,15 MHz to 0,50 MHz.5.2 Limits of conducted common mode (asymmetric mode) disturbanceat telecommunication ports 2)Table 3 – Limits of conducted common mode (asymmetric mode) disturbanceat telecommunication ports in the frequency range 0,15 MHz to 30 MHzfor class A equipment Voltage limits dB (μV) Current limits dB (μA) Frequency rangeMHzQuasi-peak Average Quasi-peak Average0,15 to 0,597 to 87 84 to 74 53 to 43 40 to 30 0,5 to 30 87 74 43 30 NOTE 1 The limits decrease linearly with the logarithm of the frequency in the range 0,15 MHz to 0,5 MHz.NOTE 2 The current and voltage disturbance limits are derived for use with an impedance stabilization network (ISN) which presents a common mode (asymmetric mode) impedance of 150 Ω to the telecommunication port under test (conversion factor is 20 log 10 150 / I = 44 dB).Table 4 – Limits of conducted common mode (asymmetric mode) disturbanceat telecommunication ports in the frequency range 0,15 MHz to 30 MHzfor class B equipment Voltage limits dB(μV) Current limits dB(μA) Frequency rangeMHzQuasi-peak Average Quasi-peakAverage 0,15 to 0,584 to 74 74 to 64 40 to 30 30 to 20 0,5 to 30 74 64 30 20 NOTE 1 The limits decrease linearly with the logarithm of the frequency in the range 0,15 MHz to 0,5 MHz.NOTE 2 The current and voltage disturbance limits are derived for use with an impedance stabilization network (ISN) which presents a common mode (asymmetric mode) impedance of 150 Ω to the telecommunication port under test (conversion factor is 20 log 10 150 / I = 44 dB).6 Limits for radiated disturbanceThe EUT shall meet the limits of Table 5 or Table 6 when measured at the measuring distance R in accordance with the methods described in Clause 10. If the reading on the measuring receiver shows fluctuations close to the limit, the reading shall be observed for at least 15 s at each measurement frequency; the highest reading shall be recorded, with the exception of any brief isolated high reading, which shall be ignored.___________2) See 3.6.Table 5 – Limits for radiated disturbance of class A ITE at a measuring distance of 10 mFrequency rangeMHz Quasi-peak limits dB(μV/m)30 to 230 40230 to 1 000 47NOTE 1 The lower limit shall apply at the transition frequency.NOTE 2 Additional provisions may be required for cases where interference occurs.Table 6 – Limits for radiated disturbance of class B ITEat a measuring distance of 10 mFrequency rangeMHz Quasi-peak limits dB(μV/m)30 to 230 30230 to 1 000 37NOTE 1 The lower limit shall apply at the transition frequency.NOTE 2 Additional provisions may be required for cases where interferenceoccurs.7 Interpretation of CISPR radio disturbance limit7.1 Significance of a CISPR limit7.1.1 A CISPR limit is a limit which is recommended to national authorities for incorporation in national publications, relevant legal regulations and official specifications. It is also recom-mended that international organizations use these limits.7.1.2The significance of the limits for equipment shall be that, on a statistical basis, at least 80 % of the mass-produced equipment complies with the limits with at least 80 % confidence.7.2 Application of limits in tests for conformity of equipment in series production7.2.1Tests shall be made:7.2.1.1Either on a sample of equipment of the type using the statistical method of evaluation set out in 7.2.3.7.2.1.2Or, for simplicity's sake, on one equipment only.7.2.2Subsequent tests are necessary from time to time on equipment taken at random from production, especially in the case referred to in 7.2.1.2.7.2.3Statistically assessed compliance with limits shall be made as follows:This test shall be performed on a sample of not less than five and not more than 12 items of the type. If, in exceptional circumstances, five items are not available, a sample of four or three shall be used. Compliance is judged from the following relationship:x kS +≤n L wherex is the arithmetic mean of the measured value of n items in the sample()S n x x n 2n 211=−−∑x n is the value of the individual itemL is the appropriate limitk is the factor derived from tables of the non-central t -distribution which assures with 80 %confidence that 80 % of the type is below the limit; the value of k depends on the sample size n and is stated below.The quantities x n , x , S n and L are expressed logarithmically: dB(μV), dB(μV/m) or dB(pW). n3 4 5 6 7 8 9 10 11 12 k 2,04 1,69 1,52 1,42 1,35 1,30 1,27 1,24 1,21 1,207.2.4 The banning of sales, or the withdrawal of a type approval, as a result of a dispute shall be considered only after tests have been carried out using the statistical method of evaluation in accordance with 7.2.1.1.8 General measurement conditions8.1 Ambient noiseA test site shall permit disturbances from the EUT to be distinguished from ambient noise. The suitability of the site in this respect can be determined by measuring the ambient noise levels with the EUT inoperative and ensuring that the noise level is at least 6 dB below the limits specified in Clauses 5 and 6.If at certain frequency bands the ambient noise is not 6 dB below the specified limit, the methods shown in 10.5 may be used to show compliance of the EUT to the specified limits. It is not necessary that the ambient noise level be 6 dB below the specified limit where both ambient noise and source disturbance combined do not exceed the specified limit. In this case the source emanation is considered to satisfy the specified limit. Where the combined ambient noise and source disturbance exceed the specified limit, the EUT shall not be judged to fail the specified limit unless it is demonstrated that, at any measurement frequency for which the limit is exceeded, two conditions are met:a) the ambient noise level is at least 6 dB below the source disturbance plus ambient noiselevel;b) the ambient noise level is at least 4,8 dB below the specified limit.。

middlebury 数据集评估指标 -回复

middlebury 数据集评估指标-回复Middlebury数据集评估指标是用于评估计算机视觉算法性能的一组标准，由Middlebury大学的Daniel Scharstein和Richard Szeliski开发。

该数据集广泛应用于光流估计、立体匹配和场景重建等计算机视觉任务的评估中，被视为此领域内的基准。

1. 数据集介绍：Middlebury数据集包含多个具有挑战性的场景，例如室内、室外、自然景观等，涵盖了多个光照条件和物体形状。

数据集提供了带有像素级标注的参考结果，用于评估算法的准确性和鲁棒性。

每个数据集都有一对输入图像，通常包括参考图像和未知图像（待估计结果）。

标注结果可以用于计算误差度量指标，评估算法的性能表现。

2. 评估指标：Middlebury数据集评估算法的性能使用一组常用的指标，包括平均角误差、平均端点误差和光流场密度。

- 平均角误差（Average Angular Error）：该指标用于评估光流估计算法的精度。

它计算了估计光流向量与真实光流向量之间的角度。

通过对每个像素处角度误差的平均值进行计算，可得到整个图像的平均角误差。

- 平均端点误差（Average Endpoint Error）：该指标用于评估立体匹配算法和视觉里程计算法等任务的性能。

它测量了估计像素位置与真实位置之间的欧氏距离。

通过对每个像素处误差的平均值进行计算，可得到整个图像的平均端点误差。

- 光流场密度（Flow Field Density）：该指标用于评估光流估计算法的有效性。

它表示在光流场中存在有效光流向量的比例。

对于给定的图像，该值可以帮助衡量算法在各个区域的光流估计能力，以及是否存在无效的或噪声影响的光流向量。

3. 评估过程：针对Middlebury数据集，评估算法的过程可以分为以下几个步骤：- 数据准备：选择合适的数据集以及标注结果，确保数据集的多样性和代表性。

对于相应任务，例如光流估计，需要选择光流场标注的参考结果。

求解不定信赖域子问题的显示欧拉方法

求解不定信赖域子问题的显示欧拉方法
李琳俊;王希云
【期刊名称】《宁夏师范学院学报》
【年(卷),期】2016(037)006
【摘要】对于Hessian阵为不定矩阵的情形,通过修改Cholesky分解对其修正,再用显式欧拉法解新的信赖域子问题,提出解不定信赖域子问题的显示欧拉方法.通过将此方法与修正分段割线法、精确求解法的数值结果对比,说明新算法有效可行,拓宽了对不定信赖域子问题的研究.
【总页数】6页(P14-19)
【作者】李琳俊;王希云
【作者单位】太原科技大学应用科学学院,山西太原030024;太原科技大学应用科学学院,山西太原030024
【正文语种】中文
【中图分类】O221
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2.一种改进的求解信赖域子问题的欧拉切线法 [J], 贾新辉;王希云;李琳俊
3.求解不定信赖域子问题的Adams四阶方法 [J], 李琳俊;王英慧;王希云
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lsb隐写的数学建模

lsb隐写的数学建模摘要：1.LSB 隐写术的概述2.LSB 隐写术的数学模型3.LSB 隐写术在图像和音频处理中的应用4.LSB 隐写术的优缺点分析5.总结正文：1.LSB 隐写术的概述LSB（Least Significant Bit，最低有效位）隐写术是一种常见的数字隐写技术，其主要思想是将秘密信息的每个比特替换到原始文件中数据的最低有效位。

由于这种替换对原始文件的影响非常小，所以难以察觉。

LSB 隐写术广泛应用于图像、音频等多媒体文件的隐藏信息传递。

2.LSB 隐写术的数学模型LSB 隐写术的数学模型主要包括两个部分：一是将秘密信息编码到原始文件中，二是从原始文件中解码出秘密信息。

（1）编码部分：设原始文件的长度为N，秘密信息的长度为M，则秘密信息可以表示为一个长度为M 的二进制序列。

将这个二进制序列按照LSB 的顺序嵌入到原始文件中，得到一个新的文件。

这里需要解决的问题是如何将秘密信息的每个比特与原始文件的数据进行替换，使得替换后的文件在视觉或听觉上与原始文件差别不大。

（2）解码部分：在接收端，需要从原始文件中提取出秘密信息。

这可以通过特定的算法实现，例如在图像处理中，可以采用基于像素的分析方法；在音频处理中，可以采用基于音频信号处理的方法。

3.LSB 隐写术在图像和音频处理中的应用（1）在图像处理中的应用：LSB 隐写术在图像处理中的主要步骤包括：将秘密信息编码到原始图像中，以及从原始图像中解码出秘密信息。

编码过程中，可以将秘密信息的每个比特替换到原始图像的每个像素的LSB 中。

解码过程中，可以通过分析原始图像的像素值来提取出秘密信息。

（2）在音频处理中的应用：LSB 隐写术在音频处理中的原理与图像处理类似。

编码过程中，可以将秘密信息的每个比特替换到原始音频信号的每个采样点的LSB 中。

解码过程中，可以通过分析原始音频信号的采样值来提取出秘密信息。

4.LSB 隐写术的优缺点分析优点：（1）隐蔽性强：由于LSB 隐写术是将秘密信息隐藏在原始文件的最低有效位中，所以难以察觉。

groupnorm作用 -回复

groupnorm作用-回复"GroupNorm作用"是一个广泛的主题，涉及多个领域，从计算机科学到社会科学。

在这篇文章中，我们将逐步回答关于GroupNorm作用的问题，并对其在不同领域的应用进行梳理。

我们将通过以下步骤进行讨论：1. 引言- 解释GroupNorm是什么以及它的原理。

- 简要介绍GroupNorm在计算机科学、心理学和社会科学领域的应用。

2. 计算机科学领域- 解释GroupNorm在计算机视觉中的作用。

- 讨论GroupNorm如何改善深度学习模型的训练和收敛性能。

- 举例说明GroupNorm在图像分类、目标检测和语义分割等任务中的效果。

3. 心理学领域- 讨论GroupNorm在心理学中的应用。

- 解释GroupNorm如何帮助研究人员更好地理解群体行为和个体之间的差异。

- 介绍GroupNorm在实验设计和数据分析中的作用。

4. 社会科学领域- 探讨GroupNorm在社会科学中的作用。

- 讨论GroupNorm如何帮助解释和理解群体动力和社会规范的形成。

- 举例说明GroupNorm如何应用于研究团队合作、社会网络和文化变迁等方面。

5. 结论- 总结GroupNorm的作用及其在不同领域的应用。

- 强调GroupNorm的潜力和未来发展方向。

在这篇文章中，我们将从不同领域的角度对GroupNorm进行全面而深入的讨论。

通过理解和应用GroupNorm，我们可以更好地理解群体行为和个体差异，提高深度学习模型的性能，解释和预测社会动态。

希望读者通过本文能够对GroupNorm有更深入的了解，并了解其在不同领域的应用前景。

matlab计算超边度

matlab计算超边度【最新版】目录1.MATLAB 简介2.超边度的定义3.MATLAB 计算超边度的方法4.超边度的应用5.总结正文1.MATLAB 简介MATLAB（Matrix Laboratory）是一款广泛应用于科学计算、数据分析和可视化的编程语言。

它拥有强大的矩阵计算能力，可以方便地处理和分析大量数据。

在网络科学领域，MATLAB 被广泛用于研究复杂网络的结构和性质。

2.超边度的定义超边度（Superdegree）是网络科学中一个重要的概念，用于描述网络节点的连接程度。

超边度是指一个节点的邻居节点的平均度数。

具体计算公式为：超边度 = Σ(邻居节点的度数) / 邻居节点数。

超边度可以反映网络中节点的重要性和稳定性，对于理解网络的拓扑结构和功能具有重要意义。

3.MATLAB 计算超边度的方法在 MATLAB 中，可以通过以下步骤计算超边度：(1) 读取网络数据：可以使用 MATLAB 内置的图形处理工具读取网络数据，例如读取 Pajek 格式或 GML 格式的数据文件。

(2) 计算邻接矩阵：根据网络数据，创建一个邻接矩阵，用于表示网络中节点之间的连接关系。

(3) 计算节点度数：对邻接矩阵进行遍历，计算每个节点的度数（即连接该节点的边数）。

(4) 计算超边度：根据节点度数和邻居节点数，计算每个节点的超边度。

4.超边度的应用超边度在网络科学中有广泛的应用，例如：(1) 识别网络中的关键节点：具有较高超边度的节点往往是网络中的关键节点，对这些节点进行干预可以有效地破坏网络的结构和功能。

(2) 分析网络的稳定性：超边度可以用于评估网络的稳定性，具有较低超边度的网络往往更加稳定。

(3) 预测网络的演化：超边度可以用于预测网络的演化趋势，随着网络规模的增大，超边度往往会减小。

5.总结MATLAB 作为一种强大的科学计算工具，可以方便地用于计算网络中的超边度。

聚类研究sim指标

Sim（Similarity）指标是一种衡量聚类效果的重要指标，通常用于评估聚类算法的性能。

Sim 指标可以通过计算同一聚类中的样本之间的相似度来衡量聚类的质量。

Sim指标越高，说明聚类效果越好。

Sim指标的计算方法如下：Sim(C,C)=1n∑i=1n∑j=1nCijC.i=Cj=1n∑i=1n∑j=1nCij(i,j)Cij=1n∑k=1n∑l=1nCikCil(k,l)Cij=CikCil(i,j)k=l=其中，Cij表示聚类中心C和样本i之间的距离，C表示聚类中心集合，C表示样本集合。

Sim(C,C)表示聚类中心之间的相似度，通过求平均值得到一个平均相似度，即可用于衡量聚类效果。

聚类分析是一个将数据分成几个簇的过程，其中每个簇都由一组相似的样本组成。

因此，为了更好地理解和应用Sim指标，我们需要理解以下两个方面：一、样本间的相似性样本间的相似性是衡量聚类效果的重要因素之一。

在聚类分析中，我们通常使用距离度量来衡量样本间的相似性。

距离度量越小，样本间的相似性越高。

常用的距离度量方法包括欧氏距离、曼哈顿距离等。

Sim指标正是基于样本间的距离度量来衡量聚类效果的。

二、聚类效果的评价Sim指标作为聚类效果的评价指标之一，需要与其他评价指标一起使用。

常用的评价指标还包括轮廓系数、切合度指数等。

通过综合使用多种评价指标，我们可以全面了解聚类算法的性能。

同时，我们也需要注意聚类效果的评估需要考虑不同的应用场景和数据集。

例如，在医学研究中，聚类分析可能更多地关注疾病类型的分类；而在市场研究中，可能更多地关注消费者行为的分析。

因此，我们需要在具体应用场景下选择合适的评价指标和方法。

总的来说，Sim指标作为衡量聚类效果的重要指标之一，其计算方法简单易懂。

同时，与其他评价指标一起使用可以更好地了解聚类算法的性能和适用性。

然而，需要注意的是Sim指标并不能完全代表聚类分析的质量，因此我们需要综合考虑其他因素来进行评估和选择合适的算法。

非负矩阵分解的复杂网络社团检测方法

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非负矩阵分解的复杂网络社团检测方法
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纹理物体缺陷的视觉检测算法研究--优秀毕业论文

摘要
在竞争激烈的工业自动化生产过程中，机器视觉对产品质量的把关起着举足轻重的作用，机器视觉在缺陷检测技术方面的应用也逐渐普遍起来。与常规的检测技术相比，自动化的视觉检测系统更加经济、快捷、高效与安全。纹理物体在工业生产中广泛存在，像用于半导体装配和封装底板和发光二极管，现代化电子系统中的印制电路板，以及纺织行业中的布匹和织物等都可认为是含有纹理特征的物体。本论文主要致力于纹理物体的缺陷检测技术研究，为纹理物体的自动化检测提供高效而可靠的检测算法。纹理是描述图像内容的重要特征，纹理分析也已经被成功的应用与纹理分割和纹理分类当中。本研究提出了一种基于纹理分析技术和参考比较方式的缺陷检测算法。这种算法能容忍物体变形引起的图像配准误差，对纹理的影响也具有鲁棒性。本算法旨在为检测出的缺陷区域提供丰富而重要的物理意义，如缺陷区域的大小、形状、亮度对比度及空间分布等。同时，在参考图像可行的情况下，本算法可用于同质纹理物体和非同质纹理物体的检测，对非纹理物体的检测也可取得不错的效果。在整个检测过程中，我们采用了可调控金字塔的纹理分析和重构技术。与传统的小波纹理分析技术不同，我们在小波域中加入处理物体变形和纹理影响的容忍度控制算法，来实现容忍物体变形和对纹理影响鲁棒的目的。最后可调控金字塔的重构保证了缺陷区域物理意义恢复的准确性。实验阶段，我们检测了一系列具有实际应用价值的图像。实验结果表明本文提出的纹理物体缺陷检测算法具有高效性和易于实现性。关键字: 缺陷检测；纹理；物体变形；可调控金字塔；重构
Keywords: defect detection, texture, object distortion, steerable pyramid, reconstruction
II

BUILDINGINFORMATIONMODELING

Building Information ModelingIntroductionBuilding Information Modeling (BIM) is a process that involves the creation and management of digital representations of physical and functional characteristics of buildings. BIM provides a collaborative platform for architects, engineers, contractors, and other stakeholders involved in the construction industry to work together on a virtual model of a building, enabling better coordination, communication, and visualization throughout the entire lifecycle of the project.Benefits of BIMBIM offers several benefits compared to traditional 2D drafting and design methods:1.Improved collaboration: BIM allows differentdisciplines to work together on a shared model, reducing conflicts and improving coordination between teams. This collaboration leads to improved efficiency and reducederrors during construction.2.Visualization and simulation: BIM enables thecreation of realistic 3D models that can be visualized and simulated before construction begins. This allowsstakeholders to better understand the design, identifypotential issues, and make informed decisions before costly construction mistakes occur.3.Clash detection: BIM software can automatically detect clashes or conflicts between different elements of the design, such as MEP systems and structural components. This helps to identify and resolve clashes early in the design phase, reducing the need for costly rework during construction.4.Improved communication: BIM facilitates better communication between project teams through the use of a centralized database. All stakeholders have access to the most up-to-date information, reducing misunderstandings and improving decision-making.5.Efficient cost estimation: BIM software can generate accurate quantity takeoffs and cost estimates based on the 3D model, reducing the time and effort required for manual calculations. This helps to improve the accuracy of cost estimation and reduce the risk of cost overruns.BIM ProcessThe BIM process typically consists of the following key steps:1.Conceptualization and design: The first step in the BIM process is to create a conceptual design of the building using BIM software. This involves defining the basic architectural and structural elements of the building.2.Collaborative modeling: After the conceptual design is complete, different disciplines, such as architects, engineers, and contractors, collaborate on the model to addfurther details. This includes the addition of MEP systems, structural elements, and other building components.3.Clash detection and coordination: Once the modelis complete, it is checked for clashes and conflicts usingclash detection software. Any clashes or conflicts areresolved, and coordination between different disciplines is ensured to avoid errors during construction.4.Construction documentation: The BIM model isused to generate construction documentation, includingdetailed drawings and specifications. These documents are used by contractors during the construction phase.5.Construction and facility management: Duringthe construction phase, the BIM model is used to monitor the progress of the project and support decision-making.After construction, the BIM model serves as a valuableresource for facility management, allowing for efficientoperation and maintenance of the building.BIM ToolsThere are several BIM software tools available in the market that support the creation and management of BIM models. Some popular BIM tools include:•Autodesk Revit•ArchiCAD•Bentley MicroStation•Tekla StructuresThese tools provide a wide range of features and functionalities, including 3D modeling, clash detection, cost estimation, and construction documentation generation. The choice of the BIM tool depends on the specific requirements of the project and the preferences of the project team.ConclusionBuilding Information Modeling (BIM) has revolutionized the construction industry by improving collaboration, communication, and visualization throughout the entire project lifecycle. BIM enables stakeholders to work together on a shared model, detect and resolve clashes early, and generate accurate construction documentation. By embracing BIM and leveraging the power of BIM software tools, construction professionals can improve the efficiency, quality, and sustainability of their projects.。

ig数学_normsdist函数_解释说明以及概述

ig数学normsdist函数解释说明以及概述1. 引言1.1 概述本文旨在深入介绍和解释IG数学中的normsdist函数，并对其定义和概述进行说明。

我们将详细探讨该函数的用途、计算方法和公式推导，并通过金融风险管理中的应用案例分析加深理解。

最后，对normsdist函数进行总结评价，并展望其未来发展趋势。

1.2 文章结构本文共分为五个主要部分。

首先是引言部分，对整篇文章进行概述和介绍。

接下来是normsdist函数的定义与用途，包括普通分布函数的介绍、normsdist函数的定义与特点以及它在实际应用中的作用。

第三部分是normsdist函数的计算方法与公式推导，将详细解释该函数的数学原理、计算方法以及相关公式的推导过程。

第四部分是normsdist函数在金融风险管理中的应用案例分析，包括金融风险管理概述、具体应用场景举例以及相关案例分析和结果讨论。

最后一部分是结论与展望，总结对normsdist函数的评价，并展望未来研究方向和发展趋势。

1.3 目的本文的目的在于全面解释和概述normsdist函数，并揭示其在金融风险管理中的重要性和应用价值。

通过对normsdist函数的介绍、计算方法的详解、公式推导过程以及具体应用案例的分析，读者可以更好地理解该函数，掌握其运用方法，并将其应用于实际问题中。

同时，本文也希望能为未来对normsdist函数进行深入研究和发展的学者提供参考和借鉴。

2. normsdist函数的定义与用途：2.1 普通分布函数的介绍：普通分布是统计学中最常见的概率分布之一，也被称为高斯分布或正态分布。

它具有对称、钟形曲线的特点，其参数由均值和标准差确定。

2.2 normsdist函数的定义与特点：normsdist函数是Excel中的一个数学函数，它用于计算给定值的标准正态累积分布（cumulative distribution）值。

标准正态累积分布是指在均值为0、标准差为1的条件下，随机变量小于等于给定值的概率。

stable diffusion室内建筑语义表

稳定扩散室内建筑语义表是指在建筑设计和室内装饰中，设计师和装饰师通过运用稳定扩散的原理，结合建筑空间和室内功能需求，对建筑语义进行梳理和设计的过程。

稳定扩散的概念源自于建筑学和室内设计领域，强调在室内环境中，通过合理的布局、材料运用和光线设计等手段，使得建筑空间的语义能够得到稳定而平衡的扩散，从而给人以舒适、和谐的感受。

在建筑学中，室内空间的语义非常重要，它不仅仅关乎于功能性的满足，更涉及到人们对空间的感知、理解和情感体验。

稳定扩散室内建筑语义表的设计，旨在创造出一个能够平衡传达建筑语义的空间环境，使人们在其中能够得到舒适和愉悦的体验。

稳定扩散室内建筑语义表需要考虑空间的功能性需求。

在室内设计中，功能性是首要考虑的因素，因为空间的设计最终要为人们的生活、工作和娱乐提供便利和舒适。

在稳定扩散的理念下，设计师需要充分考虑到空间的使用需求，合理布局各个功能区域，确保其功能性得到最大的发挥。

稳定扩散室内建筑语义表还需要考虑空间的材料运用和装饰手法。

不同的材料和装饰手法会对空间的语义产生不同的影响，稳定扩散的设计理念要求设计师在材料和装饰的选择上要小心谨慎，确保它们能够融入空间，稳定而适度地扩散建筑的语义。

另外，光线设计也是稳定扩散室内建筑语义表中至关重要的一环。

光线不仅能够照亮空间，更能够影响人们对空间的感知和情感体验。

在稳定扩散的设计理念下，设计师需要考虑到光线的颜色、亮度和角度等因素，确保光线能够稳定扩散在空间中，为人们营造出舒适、和谐的环境。

稳定扩分室内建筑语义表是建筑设计和室内装饰中非常重要的一环。

通过合理布局、材料运用、装饰手法和光线设计等手段，使得建筑空间的语义能够稳定而平衡地扩散，为人们创造出舒适、和谐的室内环境。

希望设计师和装饰师们在日常的设计工作中能够充分重视稳定扩散室内建筑语义表，为人们创造出更加美好的生活空间。

在稳定扩散室内建筑语义表的设计中，建筑师和设计师需要充分考虑到空间的整体氛围和情感体验。

sentrality翻译

sentrality翻译sentrality（中文译为中心性）是一种用于衡量网络中节点重要性的概念。

在网络分析中，中心性指标可以衡量节点在网络中的中心位置和影响力。

以下是一些关于sentrality的用法和中英文对照例句：1. Degree centrality（度中心性）：衡量节点在网络中的连接程度。

Example: The degree centrality of a node is calculated by counting the number of edges it has.（节点的度中心性通过计算其拥有的边的数量来衡量。

）2. Betweenness centrality（介数中心性）：衡量节点在网络中的桥梁作用。

Example: A node with high betweenness centrality is likely to control the flow of information between different clusters in the network.（具有高介数中心性的节点很可能控制网络中不同群集之间的信息流动。

）3. Closeness centrality（接近中心性）：衡量节点与其他节点之间的距离。

Example: A node with high closeness centrality can quickly reach other nodes in the network, indicating its importance in spreading information efficiently.（具有高接近中心性的节点可以快速到达网络中的其他节点，这表明它在有效传播信息方面的重要性。

）4. Eigenvector centrality（特征向量中心性）：衡量节点与其他重要节点的关联程度。

Example: Eigenvector centrality assigns higher scores to nodes that are connected to other nodes with high centrality.（特征向量中心性将更高的分数分配给与具有高中心性的其他节点相连的节点。

normalization对模型的作用 -回复

normalization对模型的作用-回复【normalization对模型的作用】一篇1500-2000字文章正文：当我们构建机器学习模型时，数据预处理是非常重要的一个步骤。

数据规范化（Normalization）是其中的一种常用方法，用于将不同范围的数据转换为统一的标准范围。

在这篇文章中，我们将一步一步回答Normalization对模型的作用。

首先，让我们了解一下为什么需要数据规范化。

在机器学习中，我们经常会遇到不同特征的数据范围差异很大的情况。

例如，一个特征的值范围在0到1之间，而另一个特征的值范围在100到1000之间。

如果不对这些特征进行统一的处理，会导致模型对于那些数值较大的特征更为敏感，从而影响模型的性能。

因此，Normalization的主要目标是将数据转换为具有统一范围的值。

下面我们将详细讨论Normalization对模型的几个重要作用。

首先，Normalization可以帮助加速模型的收敛速度。

在训练机器学习模型时，通常使用优化算法来最小化损失函数。

这些算法通常将学习速率与梯度相乘来决定每一步的更新量。

如果不对输入数据进行规范化，数值较大的特征将会对模型的学习速度产生较大的影响，可能导致较慢的模型收敛。

通过对数据进行Normalization，可以使特征的值都处于较小的范围内，从而更好地控制学习速率，加速模型的收敛。

其次，Normalization可以提高模型的性能。

在一些机器学习算法中，例如K最近邻算法（K Nearest Neighbors）和支持向量机（Support Vector Machines），特征的尺度会直接影响到模型的距离计算或者决策边界的定义。

如果输入数据的特征尺度不统一，模型可能会偏好那些值范围较大的特征，而忽略那些值范围较小的特征。

通过对数据进行Normalization，可以确保所有特征都在相似的尺度下进行计算，减少了尺度差异可能导致的偏差，从而提高了模型的性能。

土木工程项目管理建筑信息模型BIM外文翻译文献

文献信息文献标题：Exploitation and Benefits of BIM in Construction Project Management（建筑信息模型（BIM）在建设工程项目管理中的开发与效益）文献作者：Peter Mesároš，Tomáš Mandičák文献出处：《IOP Conference Series: Materials Science and Engineering. IOP Publishing》,2017,245(6):062056.字数统计：英文2319单词，12930字符；中文3709汉字外文文献Exploitation and Benefits of BIM in Construction ProjectManagementAbstract BIM is increasingly getting into the awareness in construction industry. BIM is the process of creating and data managing of the building during its life cycle. BIM became a part of management tools in modern construction companies. Construction projects have a number of participants. It means difficulty process of construction project management and a serious requirement for processing the huge amount of information including design, construction, time and cost parameters, economic efficiency and sustainability. Progressive information and communication technologies support cost management and management of construction project. One of them is Building Information Modelling. Aim of the paper is to examine the impact of BIM exploitation and benefits on construction project management in Slovak companies.1.IntroductionThe exploitation of progressive technologies in the construction project management represents a greater potential each day. The possibility of using new technologies in construction project management (especially for cost management,cost reducing, design of buildings, drawing and planning of construction projects generally) is steadily increasing by developing of new software solutions. According to Mesároš et al., cost management is therefore an essential condition for the effective management of construction projects. In fact, the cost reducing is not the only one benefit of exploitation progressive technology. According to other researchers, it is nowadays necessary to analyse the other benefits that new technologies bring in every area. In construction project management, BIM technology is one of the possible and available solutions for the above mentioned tasks.BIM (Building Information Modelling) therefore was generally mentioned and defined in a number of publications, conferences and workshops. Other authors ware talking about BIM like the term that is increasingly getting into the awareness in construction industry. The first mention of the BIM concept was recorded in 2002. Very often, the concept of BIM is perceived as a computer program or a 3D model that is only part of it. BIM concept has several definitions. Building information modelling is the process of creating and data managing about the building model during its life cycle. According to National Institute of Building Science, information obtained through information modelling are crucial for effective and accurate design of construction documents, construction planning, cost estimating and predicting traffic building. Information modelling thus not only creates a 3D model, but 4D (time), 5D (cost) and XD model. In addition, it is possible to say that BIM is the tool for managing relations between the participants a construction project. BIM is currently the most common denomination for a new way of approaching the design, construction and maintenance of buildings.Due to the overview of available resources and of the discussion of BIM, it may seem that we shall all was said about BIM and that this tool is often used. There is a question whether this is actually true. Do the construction companies really use this tool as spoken about? And what is perception of construction companies on BIM tool? What are benefits of exploitation of BIM? There are only a few questions, that are necessary discusses in BIM topic. That is basic of this research problem, what was formulated to these research questions:▪What are benefits of BIM using?▪What is perception of this benefits by construction companies?▪What is exploitation level of BIM in construction companies?▪What is impact on the biggest benefit of BIM using?There are some questions that is necessary to find the answers, when we are analysing the issue of BIM in selected market or environment in construction project management.2.Literature reviewThe issue of BIM is devoted to a series of authors. In terms of the status of basic research questions it is the right to talk primarily about research aimed on benefits of using BIM technology. According a lot of studies and investigations, cost reducing is one of the biggest benefit of BIM exploitation. Next benefits was set as time reducing, productivity increasing and more. One of the biggest benefit of BIM exploitation in construction project are cost reducing and control. It represents 60 % of respondents in their research.The other authors were talking about benefits in their investigation too. They mentioned s mainly budget aspect and design aspect as main benefit.Between mainly benefits of BIM exploitation it can be possible include time reducing and cost reducing in construction project management. It confirmed research realised by Ian and Damian. In addition to the above benefits, the authors mentioned the saving of human resources.Other research study confirmed savings of project cost by using of BIM. The biggest benefit is time reducing in schedule preparing trough BIM technology. This research described possibilities of measurement in the issue of BIM exploitation and benefits. The main area of investigation for measurement of BIM benefits was specified. Between main area it was selected by research results especially area: changes to processes, IT investments to supported improvements, business performance improvements and improved profit and ROI. Overview of selected researches and investigation is more detailed described in table 1.Table 1. Overview of selected researches and investigation on benefits of BIM exploitationBased on a lot of researches and literature resources about benefits of BIM, the list of main benefits was done for purposes of this research:▪cost reducing in construction project management▪time reducing in project documentation,▪time reducing for the entire lifecycle of the construction project, including the design phase,▪faster access to information and relevant documents all participants of construction project,▪increasing of employee productivity,▪increasing of financial control,▪support and facilitate of decision-making,▪increasing the quality of the documents, the elimination of error documentation,▪elimination of errors in the construction process – increasing of construction quality,▪increasing revenues from contracts.3.Methodology3.1.Research questions and aimsBased on the evaluation of the current state of art, basic research questions were raised:▪What are benefits of BIM using?▪What is perception of this benefits by construction companies?▪What is exploitation level of BIM in construction companies?▪What is impact on the biggest benefit of BIM using?The subject of research was Slovak construction industry. Construction project management and BIM exploitation in Slovakia is not well researched, despite frequent discussions on this issue.Based on the determination of research questions, the research objectives have been set. Main objective of this research was to analyze and quantify the benefits of BIM using in terms of Slovak construction project management. Another aim of research was to examine the exploitation of BIM tool is in Slovak construction industry. Based on this aims of research, the partial aim was set: answer to the question “what is impact of the biggest benefit of BIM using on construction project management”.3.2.Data collection and research sampleData collection was conducted by the questionnaire. Questionnaire was designed and distributed in electronic form. Questionnaire was produced by online platform FORMEES in electronic form. The research sample was approached by e-mail with the request to participate in the research. Total were interviewed 1276 of respondents(construction companies in Slovakia). It participated in the questionnaire survey 85 respondents. It represents a return of 6.66%. Generally, it is possible to return to the level of 4.31% is considered as good. Research sample is more described in Table 2.Table 2. Research sample3.3.Data processing methodData were evaluated based on several statistical methods through software STATISTICA version 12. When processing the results of research conducted within the research, mostly descriptive and inductive statistics were used. When evaluating the results of the research areas, importance index was used on the basis of which the ranking of benefits of using BIM technology has been compiled. This importance index was used by Mutesi and Kyakula in research of ICT benefits in construction industry.Index importance is determined by the relationship Ii = (Σ wi. F XI) 100 / 5n, wherein:Ii - Importance indexwi - weight is based on the Likert scale (1-5) (the weight given to response; I =1, 2, 3, 4 or 5 is response frequency = very weak/low)F XI- Response raten - Number of respondentsDue to the nature of the problem and the main objective of the paper appropriatestatistical methods that can detect and analyses relationships between research groups -Kruskal-Wallis test was selected. To determine the answer was used “Likert scale ranging” from 1 to 5 on the basis of fixed values the arithmetic average of the values has been done for the selected area under consideration. It means performance of companies. 1 - is very low performance and 5 - is the very high performance. This data was comparison with cost reducing indicator and profit.4.Discussion and resultsThe issue of use of BIM technology as already outlined, it is current topic. This research had among others to answer to the question: How BIM is used in the Slovak construction industry. This state is shown in Figure 1.Figure 1. Exploitation of BIM technology in construction project management in SlovakiaIn spite of often discusses of BIM technology, it is using in a low rate. Only 24.71 % respondents are using BIM technology in construction project management. It is very low value. A lot of construction companies do not use BIM technology. These companies try the quantifying benefits of BIM exploitation. All results are in Table 3.Table 3.Ranking of BIM benefits in Slovak construction project managementThe biggest benefit of BIM exploitation presents cost reducing in construction project management. It achieved 89.34% importance index. In comparison with other research in other countries, that´s not surprising. The second biggest benefit of use of BIM technology represents increasing the quality of the documents and elimination of error in documentation. Importance index of this benefit is on level of 87.56%. Other benefits are increasing of financial control, time reducing in project documentation, faster access to information and relevant documents all participants of construction project, faster access to information and relevant documents all participants of construction project, elimination of errors in the construction process – increasing of construction quality and time reducing for the entire lifecycle of the construction project, including the design phase. All of these benefits achieved more than 50%. Next benefits didn't achieve more than 50%. This ranking of benefits shown main advantages and quantifying these advantages based on Slovak construction companies. This ranking shows the biggest benefit of BIM exploitation. It is very necessary explores the impact BIM exploitation to cost reducing. Next figures describes impact rate of BIM exploitation to cost reducing.Figure 2. Impact rate of BIM exploitation to cost reducing in construction project management inSlovakiaThis research confirmed impact BIM to cost reducing. Companies used BIM technology achieved bigger impact rate than companies don't use BIM technology. BIM technology has impact to cost reducing. This is often reason, why this companies want to implement BIM technology.5.ConclusionsBIM technology offered a lot of functionality and it ́s very helpful tool in construction project management. Cost management is very important part of construction project management. Accurate and information based cost management may have a serious impact on the success of construction project. BIM technology has a lot of functionality, includes cost management too. Research tried to provide the answers to benefits of BIM technology. Ranking of benefits was based on Slovak construction companies. As examined, quality of documentation and cost reducing are the biggest benefit of BIM technology.中文译文建筑信息模型（BIM）在建设工程项目管理中的开发与效益摘要建筑信息模型（BIM）越来越受到建筑业的重视。

数据通信原理实验指导书

实验一编码与译码一、实验学时：2学时二、实验类型：验证型三、实验仪器：安装Matlab软件的PC机一台四、实验目的：用MATLAB仿真技术实现信源编译码、过失操纵编译码,并计算误码率。

在那个实验中咱们将观看到二进制信息是如何进行编码的。

咱们将要紧了解：1．目前用于数字通信的基带码型2．过失操纵编译码五、实验内容：1．经常使用基带码型（1）利用MATLAB 函数wave_gen 来产生代表二进制序列的波形,函数wave_gen 的格式是：wave_gen(二进制码元,‘码型’,Rb)此处Rb 是二进制码元速度,单位为比特/秒（bps）。

产生如下的二进制序列：>> b = [1 0 1 0 1 1];利用Rb=1000bps 的单极性不归零码产生代表b的波形且显示波形x，填写图1-1：>> x = wave_gen(b,‘unipolar_nrz’,1000);>> waveplot(x)（2）用如下码型重复步骤（1）（提示：能够键入“help wave_gen”来获取帮忙），并做出相应的记录：a 双极性不归零码b 单极性归零码c 双极性归零码d 曼彻斯特码(manchester)x 10-3x 10-3图1-1 单极性不归零码图1-2双极性不归零码x 10-3x 10-32．过失操纵编译码（1）利用MATLAB 函数encode 来对二进制序列进行过失操纵编码, 函数encode 的格式是：A ．code = encode(msg,n,k,'linear/fmt',genmat)B ．code = encode(msg,n,k,'cyclic/fmt',genpoly)C ．code = encode(msg,n,k,'hamming/fmt',prim_poly)其中A ．用于产生线性分组码，B ．用于产生循环码，C ．用于产生hamming 码，msg 为待编码二进制序列，n 为码字长度，k 为分组msg 长度，genmat 为生成矩阵，维数为k*n ，genpoly 为生成多项式,缺省情形下为cyclpoly(n,k)。

空间句法的量化指标

空间句法的量化指标空间句法（Spatial Syntax）的量化指标主要用于描述和分析城市空间结构的特征和模式。

以下是一些常用的空间句法量化指标：1. 道路密度（Road Density）：指城市道路网络的密集程度，可通过计算单位面积内的道路长度来衡量。

2. 连通度（Connectivity）：指城市道路网络中的连通性程度，常用指标包括连接数（Connectivity Degree）、网络密度（Network Density）和平均最短路径长度（Average Shortest Path Length）等。

3. 可达性（Accessibility）：指城市不同区域的可达性程度，包括正向可达性（从某一区域到其他区域的便利程度）和反向可达性（从其他区域到某一区域的便利程度）。

4. 中心度（Centrality）：指城市空间中的中心程度，常用指标包括中心性（Centrality Degree）和中心距离（Centrality Distance）等。

5. 自由度（Integration）：指城市空间中的自由流动程度，包括自由度指数（Integration Index）和自由度梯度（Integration Gradient）等。

6. 分形维度（Fractal Dimension）：指城市空间形态的复杂程度，可通过计算城市边界、街道网络或建筑物形态的分形维度来衡量。

7. 线性维度（Linear Dimension）：指城市线性要素（如道路、河流等）的长度量化指标，包括总长度、平均长度和线性密度等。

8. 笑脸指数（Smile Index）：用于评估城市公共空间的多样性和流动性，从而衡量城市的活力和吸引力。

需要注意的是，以上仅列举了一些常见的空间句法量化指标，具体的指标选择和计算方法可能会因研究目的和所采用的空间分析工具而有所差异。

networkx中模块度的计算函数

在进行网络分析时，模块度的计算是一个非常重要的指标，它可以帮助我们衡量网络中社区结构的紧密程度。

而在Python中，常常使用networkx库来进行复杂网络的分析和可视化。

在本文中，我将会对networkx中模块度的计算函数进行全面评估，并根据此撰写一篇有价值的文章。

让我们来了解一下模块度的基本概念。

模块度是用来描述网络中节点聚集在一起形成社区的程度，它的取值范围在-1到1之间。

当模块度为1时，表示网络中的社区结构非常好，节点之间的连接紧密；而当模块度为0或负值时，则表示社区结构不够紧密，节点之间的连接不够明显。

在networkx库中，有一个非常重要的模块度计算函数是munity.modularity`。

这个函数可以根据网络的拓扑结构和节点的分配情况，来计算网络的模块度。

在具体的实践中，我们可以使用这个函数来评估网络中社区结构的优劣，帮助我们更好地理解网络的内部联系和节点的分布情况。

接下来，让我们来具体了解一下如何在networkx中使用munity.modularity`函数来计算模块度。

我们需要使用`networkx`库加载网络数据，并构建网络对象。

我们可以使用munity.modularity`函数来计算网络的模块度。

在这个过程中，我们需要注意对网络的节点进行正确的分配，以确保结果的准确性和可靠性。

我们可以根据计算得到的模块度值，来对网络的社区结构进行评估和分析。

在实际操作中，munity.modularity`函数还可以与其他网络分析的函数和算法进行结合使用，来帮助我们更好地理解网络中节点的分布情况和社区结构。

通过使用这个函数，我们可以更深入地了解网络的内部联系和节点的聚集情况，从而为网络分析和社交网络挖掘等领域提供更加可靠的数据支持。

在总结本文时，我们可以看到，在Python的networkx库中，模块度的计算函数munity.modularity`是一个非常重要并且有价值的工具。

它可以帮助我们更好地理解网络的社区结构，评估社区的聚集程度，为网络分析和社交网络挖掘等领域提供重要的数据支持。

tdnn s-norm计算方法

tdnn s-norm计算方法
TDNN（Time Delay Neural Network）是一种用于处理时间序列数据的神经网络架构。

而S-Norm（Semantic Norm）是一种用于计算语义相似度的方法。

两者并不直接相关，可能存在误解。

1. TDNN计算方法：在TDNN中，输入序列通过一组不同大小的窗口（即时间延迟）滑动，通过卷积操作提取时序信息。

TDNN的计算方法可以分为以下步骤：
- 输入序列经过一组不同大小窗口的卷积层。

- 卷积层的输出经过非线性激活函数，如ReLU。

- 池化层对卷积层的输出进行池化操作，如最大池化或平均池化。

- 池化层的输出经过全连接层进行分类或回归等后续任务。

2. S-Norm计算方法：S-Norm是一种用于计算语义相似度的方法，主要用于衡量两个语义向量之间的相似度。

通常，S-Norm计算方法遵循以下步骤：
- 计算两个语义向量之间的余弦相似度。

- 将余弦相似度映射到[0,1]的范围内。

- 可能使用其他方法进行后处理，如线性变换。

需要注意的是，TDNN和S-Norm是两个不同的概念和方法，分别用于不同的应用领域。