Symbolic Computation of Conserved Densities, Generalized Symmetries, and Recursion Operator

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EN55022-2006

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.。

计算机辅助几何设计含参数保形有理样条插值

计算机辅助几何设计含参数保形有理样条插值

计算机辅助几何设计含参数保形有理样条插值计算机辅助几何设计(Computer-Aided Geometric Design,简称 CAGD)是计算机科学、数学和工程的交叉学科,它的发展历程可以追溯到20世纪70年代。

CAGD主要是利用计算机帮助人们完成各种几何设计任务,如曲线拟合、曲面建模、数据可视化等等。

其中,参数保形有理样条插值是CAGD中的一种基本技术之一,下面我们将对其进行详细介绍。

一、CAGD简介计算机辅助几何设计是一种利用计算机技术进行几何建模、分析、验证和制造的方法。

CAGD的应用范围非常广泛,涵盖了工业设计、航空航天、汽车制造、医学医疗、艺术设计等领域。

通过CAGD的技术手段,可以在计算机上创建数学模型,并对其进行几何变换、仿真分析、优化求解等操作,从而提高设计效率和质量。

CAGD的发展历程可以追溯到20世纪70年代,当时计算机的性能和软件工具都比较有限,所以主要应用于科学计算和工程仿真领域。

随着计算机技术的飞速发展,CAGD的应用范围也越来越广泛,涌现出了许多优秀的方法和算法,如Bezier曲线、B样条曲线、NURBS曲面、三角网格模型等等。

二、参数保形有理样条插值有理样条曲线是一种常用的数学曲线,它可以用来表示各种形状的曲线和曲面。

和其他曲线表示方法相比,有理样条曲线具有重要的优点,如良好的几何性质、局部控制性能、优秀的逼近性能等等。

参数保形有理样条插值是有理样条曲线中的一种插值方法,它可以通过已知的插值点来构造一条参数保形的有理样条曲线。

插值问题是求解函数$f(x)$在一些已知点$x_i$处的函数值$f(x_i)$的问题。

对于一些简单的函数,这个问题可以直接求解。

但是对于复杂的函数,如曲线和曲面,这个问题并不容易解决。

在实际应用中,经常需要求解一条曲线通过已知点,并且曲线在每个插值点处具有特定的曲率、斜率等属性。

这个问题就可以通过参数保形有理样条插值方法来解决。

参数保形有理样条插值是一种基于控制点的插值方法。

在伪辛几何上构作新的带仲裁认证码

在伪辛几何上构作新的带仲裁认证码
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利用有限域上奇异辛几何构造一个新的带仲裁的认证码

利用有限域上奇异辛几何构造一个新的带仲裁的认证码


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参与者 :发方 ,收方 ,敌方和仲裁人 ,共有下面五种攻击:

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IEC-61854架空线.隔离层的要求和检验

IEC-61854架空线.隔离层的要求和检验

NORMEINTERNATIONALECEI IEC INTERNATIONALSTANDARD 61854Première éditionFirst edition1998-09Lignes aériennes –Exigences et essais applicables aux entretoisesOverhead lines –Requirements and tests for spacersCommission Electrotechnique InternationaleInternational Electrotechnical Commission Pour prix, voir catalogue en vigueurFor price, see current catalogue© IEC 1998 Droits de reproduction réservés Copyright - all rights reservedAucune partie de cette publication ne peut être reproduite niutilisée sous quelque forme que ce soit et par aucunprocédé, électronique ou mécanique, y compris la photo-copie et les microfilms, sans l'accord écrit de l'éditeur.No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical,including photocopying and microfilm, without permission in writing from the publisher.International Electrotechnical Commission 3, rue de Varembé Geneva, SwitzerlandTelefax: +41 22 919 0300e-mail: inmail@iec.ch IEC web site http: //www.iec.chCODE PRIX PRICE CODE X– 2 –61854 © CEI:1998SOMMAIREPages AVANT-PROPOS (6)Articles1Domaine d'application (8)2Références normatives (8)3Définitions (12)4Exigences générales (12)4.1Conception (12)4.2Matériaux (14)4.2.1Généralités (14)4.2.2Matériaux non métalliques (14)4.3Masse, dimensions et tolérances (14)4.4Protection contre la corrosion (14)4.5Aspect et finition de fabrication (14)4.6Marquage (14)4.7Consignes d'installation (14)5Assurance de la qualité (16)6Classification des essais (16)6.1Essais de type (16)6.1.1Généralités (16)6.1.2Application (16)6.2Essais sur échantillon (16)6.2.1Généralités (16)6.2.2Application (16)6.2.3Echantillonnage et critères de réception (18)6.3Essais individuels de série (18)6.3.1Généralités (18)6.3.2Application et critères de réception (18)6.4Tableau des essais à effectuer (18)7Méthodes d'essai (22)7.1Contrôle visuel (22)7.2Vérification des dimensions, des matériaux et de la masse (22)7.3Essai de protection contre la corrosion (22)7.3.1Composants revêtus par galvanisation à chaud (autres queles fils d'acier galvanisés toronnés) (22)7.3.2Produits en fer protégés contre la corrosion par des méthodes autresque la galvanisation à chaud (24)7.3.3Fils d'acier galvanisé toronnés (24)7.3.4Corrosion causée par des composants non métalliques (24)7.4Essais non destructifs (24)61854 © IEC:1998– 3 –CONTENTSPage FOREWORD (7)Clause1Scope (9)2Normative references (9)3Definitions (13)4General requirements (13)4.1Design (13)4.2Materials (15)4.2.1General (15)4.2.2Non-metallic materials (15)4.3Mass, dimensions and tolerances (15)4.4Protection against corrosion (15)4.5Manufacturing appearance and finish (15)4.6Marking (15)4.7Installation instructions (15)5Quality assurance (17)6Classification of tests (17)6.1Type tests (17)6.1.1General (17)6.1.2Application (17)6.2Sample tests (17)6.2.1General (17)6.2.2Application (17)6.2.3Sampling and acceptance criteria (19)6.3Routine tests (19)6.3.1General (19)6.3.2Application and acceptance criteria (19)6.4Table of tests to be applied (19)7Test methods (23)7.1Visual examination (23)7.2Verification of dimensions, materials and mass (23)7.3Corrosion protection test (23)7.3.1Hot dip galvanized components (other than stranded galvanizedsteel wires) (23)7.3.2Ferrous components protected from corrosion by methods other thanhot dip galvanizing (25)7.3.3Stranded galvanized steel wires (25)7.3.4Corrosion caused by non-metallic components (25)7.4Non-destructive tests (25)– 4 –61854 © CEI:1998 Articles Pages7.5Essais mécaniques (26)7.5.1Essais de glissement des pinces (26)7.5.1.1Essai de glissement longitudinal (26)7.5.1.2Essai de glissement en torsion (28)7.5.2Essai de boulon fusible (28)7.5.3Essai de serrage des boulons de pince (30)7.5.4Essais de courant de court-circuit simulé et essais de compressionet de traction (30)7.5.4.1Essai de courant de court-circuit simulé (30)7.5.4.2Essai de compression et de traction (32)7.5.5Caractérisation des propriétés élastiques et d'amortissement (32)7.5.6Essais de flexibilité (38)7.5.7Essais de fatigue (38)7.5.7.1Généralités (38)7.5.7.2Oscillation de sous-portée (40)7.5.7.3Vibrations éoliennes (40)7.6Essais de caractérisation des élastomères (42)7.6.1Généralités (42)7.6.2Essais (42)7.6.3Essai de résistance à l'ozone (46)7.7Essais électriques (46)7.7.1Essais d'effet couronne et de tension de perturbations radioélectriques..467.7.2Essai de résistance électrique (46)7.8Vérification du comportement vibratoire du système faisceau/entretoise (48)Annexe A (normative) Informations techniques minimales à convenirentre acheteur et fournisseur (64)Annexe B (informative) Forces de compression dans l'essai de courantde court-circuit simulé (66)Annexe C (informative) Caractérisation des propriétés élastiques et d'amortissementMéthode de détermination de la rigidité et de l'amortissement (70)Annexe D (informative) Contrôle du comportement vibratoire du systèmefaisceau/entretoise (74)Bibliographie (80)Figures (50)Tableau 1 – Essais sur les entretoises (20)Tableau 2 – Essais sur les élastomères (44)61854 © IEC:1998– 5 –Clause Page7.5Mechanical tests (27)7.5.1Clamp slip tests (27)7.5.1.1Longitudinal slip test (27)7.5.1.2Torsional slip test (29)7.5.2Breakaway bolt test (29)7.5.3Clamp bolt tightening test (31)7.5.4Simulated short-circuit current test and compression and tension tests (31)7.5.4.1Simulated short-circuit current test (31)7.5.4.2Compression and tension test (33)7.5.5Characterisation of the elastic and damping properties (33)7.5.6Flexibility tests (39)7.5.7Fatigue tests (39)7.5.7.1General (39)7.5.7.2Subspan oscillation (41)7.5.7.3Aeolian vibration (41)7.6Tests to characterise elastomers (43)7.6.1General (43)7.6.2Tests (43)7.6.3Ozone resistance test (47)7.7Electrical tests (47)7.7.1Corona and radio interference voltage (RIV) tests (47)7.7.2Electrical resistance test (47)7.8Verification of vibration behaviour of the bundle-spacer system (49)Annex A (normative) Minimum technical details to be agreed betweenpurchaser and supplier (65)Annex B (informative) Compressive forces in the simulated short-circuit current test (67)Annex C (informative) Characterisation of the elastic and damping propertiesStiffness-Damping Method (71)Annex D (informative) Verification of vibration behaviour of the bundle/spacer system (75)Bibliography (81)Figures (51)Table 1 – Tests on spacers (21)Table 2 – Tests on elastomers (45)– 6 –61854 © CEI:1998 COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE––––––––––LIGNES AÉRIENNES –EXIGENCES ET ESSAIS APPLICABLES AUX ENTRETOISESAVANT-PROPOS1)La CEI (Commission Electrotechnique Internationale) est une organisation mondiale de normalisation composéede l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a pour objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines de l'électricité et de l'électronique. A cet effet, la CEI, entre autres activités, publie des Normes internationales.Leur élaboration est confiée à des comités d'études, aux travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les organisations internationales, gouvernementales et non gouvernementales, en liaison avec la CEI, participent également aux travaux. La CEI collabore étroitement avec l'Organisation Internationale de Normalisation (ISO), selon des conditions fixées par accord entre les deux organisations.2)Les décisions ou accords officiels de la CEI concernant les questions techniques représentent, dans la mesuredu possible un accord international sur les sujets étudiés, étant donné que les Comités nationaux intéressés sont représentés dans chaque comité d’études.3)Les documents produits se présentent sous la forme de recommandations internationales. Ils sont publiéscomme normes, rapports techniques ou guides et agréés comme tels par les Comités nationaux.4)Dans le but d'encourager l'unification internationale, les Comités nationaux de la CEI s'engagent à appliquer defaçon transparente, dans toute la mesure possible, les Normes internationales de la CEI dans leurs normes nationales et régionales. Toute divergence entre la norme de la CEI et la norme nationale ou régionale correspondante doit être indiquée en termes clairs dans cette dernière.5)La CEI n’a fixé aucune procédure concernant le marquage comme indication d’approbation et sa responsabilitén’est pas engagée quand un matériel est déclaré conforme à l’une de ses normes.6) L’attention est attirée sur le fait que certains des éléments de la présente Norme internationale peuvent fairel’objet de droits de propriété intellectuelle ou de droits analogues. La CEI ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits de propriété et de ne pas avoir signalé leur existence.La Norme internationale CEI 61854 a été établie par le comité d'études 11 de la CEI: Lignes aériennes.Le texte de cette norme est issu des documents suivants:FDIS Rapport de vote11/141/FDIS11/143/RVDLe rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant abouti à l'approbation de cette norme.L’annexe A fait partie intégrante de cette norme.Les annexes B, C et D sont données uniquement à titre d’information.61854 © IEC:1998– 7 –INTERNATIONAL ELECTROTECHNICAL COMMISSION––––––––––OVERHEAD LINES –REQUIREMENTS AND TESTS FOR SPACERSFOREWORD1)The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprisingall national electrotechnical committees (IEC National Committees). The object of the IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, the IEC publishes International Standards. Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.2)The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, aninternational consensus of opinion on the relevant subjects since each technical committee has representation from all interested National Committees.3)The documents produced have the form of recommendations for international use and are published in the formof standards, technical reports or guides and they are accepted by the National Committees in that sense.4)In order to promote international unification, IEC National Committees undertake to apply IEC InternationalStandards transparently to the maximum extent possible in their national and regional standards. Any divergence between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the latter.5)The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for anyequipment declared to be in conformity with one of its standards.6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subjectof patent rights. The IEC shall not be held responsible for identifying any or all such patent rights. International Standard IEC 61854 has been prepared by IEC technical committee 11: Overhead lines.The text of this standard is based on the following documents:FDIS Report on voting11/141/FDIS11/143/RVDFull information on the voting for the approval of this standard can be found in the report on voting indicated in the above table.Annex A forms an integral part of this standard.Annexes B, C and D are for information only.– 8 –61854 © CEI:1998LIGNES AÉRIENNES –EXIGENCES ET ESSAIS APPLICABLES AUX ENTRETOISES1 Domaine d'applicationLa présente Norme internationale s'applique aux entretoises destinées aux faisceaux de conducteurs de lignes aériennes. Elle recouvre les entretoises rigides, les entretoises flexibles et les entretoises amortissantes.Elle ne s'applique pas aux espaceurs, aux écarteurs à anneaux et aux entretoises de mise à la terre.NOTE – La présente norme est applicable aux pratiques de conception de lignes et aux entretoises les plus couramment utilisées au moment de sa rédaction. Il peut exister d'autres entretoises auxquelles les essais spécifiques décrits dans la présente norme ne s'appliquent pas.Dans de nombreux cas, les procédures d'essai et les valeurs d'essai sont convenues entre l'acheteur et le fournisseur et sont énoncées dans le contrat d'approvisionnement. L'acheteur est le mieux à même d'évaluer les conditions de service prévues, qu'il convient d'utiliser comme base à la définition de la sévérité des essais.La liste des informations techniques minimales à convenir entre acheteur et fournisseur est fournie en annexe A.2 Références normativesLes documents normatifs suivants contiennent des dispositions qui, par suite de la référence qui y est faite, constituent des dispositions valables pour la présente Norme internationale. Au moment de la publication, les éditions indiquées étaient en vigueur. Tout document normatif est sujet à révision et les parties prenantes aux accords fondés sur la présente Norme internationale sont invitées à rechercher la possibilité d'appliquer les éditions les plus récentes des documents normatifs indiqués ci-après. Les membres de la CEI et de l'ISO possèdent le registre des Normes internationales en vigueur.CEI 60050(466):1990, Vocabulaire Electrotechnique International (VEI) – Chapitre 466: Lignes aériennesCEI 61284:1997, Lignes aériennes – Exigences et essais pour le matériel d'équipementCEI 60888:1987, Fils en acier zingué pour conducteurs câblésISO 34-1:1994, Caoutchouc vulcanisé ou thermoplastique – Détermination de la résistance au déchirement – Partie 1: Eprouvettes pantalon, angulaire et croissantISO 34-2:1996, Caoutchouc vulcanisé ou thermoplastique – Détermination de la résistance au déchirement – Partie 2: Petites éprouvettes (éprouvettes de Delft)ISO 37:1994, Caoutchouc vulcanisé ou thermoplastique – Détermination des caractéristiques de contrainte-déformation en traction61854 © IEC:1998– 9 –OVERHEAD LINES –REQUIREMENTS AND TESTS FOR SPACERS1 ScopeThis International Standard applies to spacers for conductor bundles of overhead lines. It covers rigid spacers, flexible spacers and spacer dampers.It does not apply to interphase spacers, hoop spacers and bonding spacers.NOTE – This standard is written to cover the line design practices and spacers most commonly used at the time of writing. There may be other spacers available for which the specific tests reported in this standard may not be applicable.In many cases, test procedures and test values are left to agreement between purchaser and supplier and are stated in the procurement contract. The purchaser is best able to evaluate the intended service conditions, which should be the basis for establishing the test severity.In annex A, the minimum technical details to be agreed between purchaser and supplier are listed.2 Normative referencesThe following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication of this standard, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.IEC 60050(466):1990, International Electrotechnical vocabulary (IEV) – Chapter 466: Overhead linesIEC 61284:1997, Overhead lines – Requirements and tests for fittingsIEC 60888:1987, Zinc-coated steel wires for stranded conductorsISO 34-1:1994, Rubber, vulcanized or thermoplastic – Determination of tear strength – Part 1: Trouser, angle and crescent test piecesISO 34-2:1996, Rubber, vulcanized or thermoplastic – Determination of tear strength – Part 2: Small (Delft) test piecesISO 37:1994, Rubber, vulcanized or thermoplastic – Determination of tensile stress-strain properties– 10 –61854 © CEI:1998 ISO 188:1982, Caoutchouc vulcanisé – Essais de résistance au vieillissement accéléré ou à la chaleurISO 812:1991, Caoutchouc vulcanisé – Détermination de la fragilité à basse températureISO 815:1991, Caoutchouc vulcanisé ou thermoplastique – Détermination de la déformation rémanente après compression aux températures ambiantes, élevées ou bassesISO 868:1985, Plastiques et ébonite – Détermination de la dureté par pénétration au moyen d'un duromètre (dureté Shore)ISO 1183:1987, Plastiques – Méthodes pour déterminer la masse volumique et la densitérelative des plastiques non alvéolairesISO 1431-1:1989, Caoutchouc vulcanisé ou thermoplastique – Résistance au craquelage par l'ozone – Partie 1: Essai sous allongement statiqueISO 1461,— Revêtements de galvanisation à chaud sur produits finis ferreux – Spécifications1) ISO 1817:1985, Caoutchouc vulcanisé – Détermination de l'action des liquidesISO 2781:1988, Caoutchouc vulcanisé – Détermination de la masse volumiqueISO 2859-1:1989, Règles d'échantillonnage pour les contrôles par attributs – Partie 1: Plans d'échantillonnage pour les contrôles lot par lot, indexés d'après le niveau de qualité acceptable (NQA)ISO 2859-2:1985, Règles d'échantillonnage pour les contrôles par attributs – Partie 2: Plans d'échantillonnage pour les contrôles de lots isolés, indexés d'après la qualité limite (QL)ISO 2921:1982, Caoutchouc vulcanisé – Détermination des caractéristiques à basse température – Méthode température-retrait (essai TR)ISO 3417:1991, Caoutchouc – Détermination des caractéristiques de vulcanisation à l'aide du rhéomètre à disque oscillantISO 3951:1989, Règles et tables d'échantillonnage pour les contrôles par mesures des pourcentages de non conformesISO 4649:1985, Caoutchouc – Détermination de la résistance à l'abrasion à l'aide d'un dispositif à tambour tournantISO 4662:1986, Caoutchouc – Détermination de la résilience de rebondissement des vulcanisats––––––––––1) A publierThis is a preview - click here to buy the full publication61854 © IEC:1998– 11 –ISO 188:1982, Rubber, vulcanized – Accelerated ageing or heat-resistance testsISO 812:1991, Rubber, vulcanized – Determination of low temperature brittlenessISO 815:1991, Rubber, vulcanized or thermoplastic – Determination of compression set at ambient, elevated or low temperaturesISO 868:1985, Plastics and ebonite – Determination of indentation hardness by means of a durometer (Shore hardness)ISO 1183:1987, Plastics – Methods for determining the density and relative density of non-cellular plasticsISO 1431-1:1989, Rubber, vulcanized or thermoplastic – Resistance to ozone cracking –Part 1: static strain testISO 1461, — Hot dip galvanized coatings on fabricated ferrous products – Specifications1)ISO 1817:1985, Rubber, vulcanized – Determination of the effect of liquidsISO 2781:1988, Rubber, vulcanized – Determination of densityISO 2859-1:1989, Sampling procedures for inspection by attributes – Part 1: Sampling plans indexed by acceptable quality level (AQL) for lot-by-lot inspectionISO 2859-2:1985, Sampling procedures for inspection by attributes – Part 2: Sampling plans indexed by limiting quality level (LQ) for isolated lot inspectionISO 2921:1982, Rubber, vulcanized – Determination of low temperature characteristics –Temperature-retraction procedure (TR test)ISO 3417:1991, Rubber – Measurement of vulcanization characteristics with the oscillating disc curemeterISO 3951:1989, Sampling procedures and charts for inspection by variables for percent nonconformingISO 4649:1985, Rubber – Determination of abrasion resistance using a rotating cylindrical drum deviceISO 4662:1986, Rubber – Determination of rebound resilience of vulcanizates–––––––––1) To be published.。

外文翻译---基于离散混沌映射的图像加密并行算法

外文翻译---基于离散混沌映射的图像加密并行算法
这种并行图像加密框架下,我们提出了一种新的算法,这是基于四个基本的转换。因此,我们将描述我们的算法之前,先介绍这些转换。
3.转换
3.1.A-转换
在A转换中,A代表加,能被形式化的定义如下:
a+b=c(1)
加法被定义为按位与操作
转换A有三个基本性质:
(2.1)a+a=0
(2.2)a+b=b+a(2)
(2.3)(a+b)+c=a+(b+c)
在并行模式计算时,许多的PE可以同时读取或写入相同的内存区域(即临界区),
这往往会导致意想不到的执行程序。因此,有必要在关键区域使用一些并行技术管理。
2.2.并行图像的加密框架
为了满足上述要求,我们提出了一个并行图像加密的框架,这是一个四个步骤的过程:
步骤1:整个图像被划分成若干块。
步骤2:每个PE负责确定数量块。一个区域内的像素可以充分使用有效的混乱和扩散进行操作加密。
附件C:译文
基于离散混沌映射的图像加密并行算法
摘要:
最近,针对图像加密提出了多种基于混沌的算法。然而,它们都无法在并行计算环境中有效工作。在本文中,我们提出了一个并行图像加密的框架。基于此框架内,一个使用离散柯尔莫哥洛夫流映射的新算法被提出。它符合所有并行图像加密算法的要求。此外,它是安全、快速的。这些特性使得它是一个很好的基于并行计算平台上的图像加密选择。
这个框架可以非常有效的实现整个图像的扩散。但是,它是不适合在并行计算环境中运行。这是因为当前像素的处理无法启动直到前一个像素已加密。即使有多个处理元素(PE),这种计算仍然是在一个串行模式下工作。此限制了其应用平台,因为许多基于FPGA / CPLD或者数字电路的设备可以支持并行处理。随着并行计算技术的应用,加密速度可以大大加快。

利用奇异酉几何构造新的带仲裁的认证码

利用奇异酉几何构造新的带仲裁的认证码
功 的概率分别记为 , s P, , 。 和 . 仲裁人 了解通信系统的全部但 不参与通信活动 , 只有 当发方与收方发生争执时, 才出面解 决争端 , 因此假定仲裁者总是诚实的. 文献 『 利用非奇异 辛几 何构造 了一个无仲 裁的认证码, 献f 6利用 非奇异酉几何 、非奇 2 1 文 31 — 异辛几何构造 了一系列带仲裁 的认证码, 文献f 利用奇异辛几何构造 了一个带仲 裁的认证码, 7 1 这 些结果极大地丰 富了有限典型群的几何学在认证码构造 方面的应用. 本文 利用奇异酉几何构造 了一个新的带仲裁 的认证码, 并计算 了这个码的参数与各种 攻击成功 的概率. 所有酉几何中的符号及计数公式见文献f . 8 1
设F。 日 是具有q个元素的有限域, 其中q 是素数幂. 定义F: q 的对合自同构, 面=a, 0 q 任意 取n q. ∈F 它是一个二阶自同构, 其不变域是F . q

I:I ) 0 l
/ 0

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解构主义美学对空间叙事的意义——以拉·维莱特公园为例

解构主义美学对空间叙事的意义——以拉·维莱特公园为例

accumulation of civilization, the number of spaces expressing rich spiritual content will also increase. For architects pursuing new architectural space design schemes, space narrative is undoubtedly a solution strategy. Tschumi uses the event-architecture theory in la Villette park to refer to the three parts of space, events and activities in the city through the three levels of point, line and plane. The narrative of space is well conveyed.Key words narrative space; deconstruction aesthetics; la Villette park; multiculturalism当今信息化技术发展迅速,相较于以往任何一个时代,人们受到的多样性数据冲击是前所未有的,对于空间的社会文化情感需求更加突出。

在此背景下,解构主义率先提出融合叙事领域的思想,伯纳德·屈米(Bernard Tschumi,以下简称“屈米”)作为先锋,其设计的拉·维莱特公园是建筑和景观领域运用叙事学进行创作的典例。

文章将以拉·维莱特公园设计方案为例,从建筑叙事学的视角分析该公园内建筑的形成过程与动因,剖析建筑师的思维轨迹及其作品的美学意义,从而使读者领会解构主义美学对当代空间叙事的积极作用,期望建筑师将构建更多元的人与场所的互动。

薛定谔—麦克斯韦尔方程径向解的存在性和多重性(英文)

薛定谔—麦克斯韦尔方程径向解的存在性和多重性(英文)

In 1887, the German physicist Erwin Schrödinger proposed a radial solution to the Maxwell-Schrödinger equation. This equation describes the behavior of an electron in an atom and is used to calculate its energy levels. The radial solution was found to be valid for all values of angular momentum quantum number l, which means that it can describe any type of atomic orbital.The existence and multiplicity of this radial solution has been studied extensively since then. It has been shown that there are infinitely many solutions for each value of l, with each one corresponding to a different energy level. Furthermore, these solutions can be divided into two categories: bound states and scattering states. Bound states have negative energies and correspond to electrons that are trapped within the atom; scattering states have positive energies and correspond to electrons that escape from the atom after being excited by external radiation or collisions with other particles.The existence and multiplicity of these solutions is important because they provide insight into how atoms interact with their environment through electromagnetic radiation or collisions with other particles. They also help us understand why certain elements form molecules when combined together, as well as why some elements remain stable while others decay over time due to radioactive processes such as alpha decay or beta decay.。

利用有限域上奇异辛几何构造具有仲裁的认证码

利用有限域上奇异辛几何构造具有仲裁的认证码
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基于辛几何构作一类新的带仲裁的认证码

基于辛几何构作一类新的带仲裁的认证码

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Nonlinear Dynamics and Systems Theory, 7(4) (2007) 399–408 Observer Design for a Class of

Nonlinear Dynamics and Systems Theory, 7(4) (2007) 399–408 Observer Design for a Class of

1
Introduction
We consider the problem of observer design for nonlinear single-input single-output systems. A particularly interesting class of design methods use differential geometric concepts. These design methods are based on various normal forms. In [19, 3], the observer canonical form consisting of a linear output map and linear dynamics driven by a nonlinear output injection is used. The resulting observer has exactly linear error dynamics, i.e., nonlinearities are compensated exactly. The approaches suggested in [13, 9, 10, 5] rely on the observability canonical form, which has significantly weaker existence conditions than the observer canonical form. In the observability canonical form, the observer is designed by a high-gain technique with a constant observer gain, i.e., the nonlinearities are not compensated but dominated by a linear part. For an implementation of the

TheColonialOriginsofComparativeDevelopment部分翻译

TheColonialOriginsofComparativeDevelopment部分翻译

V. 坚固性A.额外控制表4里2SLS(两阶段最小二乘法)结果的有效性依赖于假设:过去移民死亡率对当前经济表现没有直接影响。

虽然这个假设看起来合理(至少对我们来说),在这里,我们直接控制那些看起来可能与移民死亡率和经济成果相关联的变量,验证这些变量对我们的估计是否有影响,来进一步验证这个假设。

总的来说,我们发现列入这些变量时我们的结果变化得很少,而且很多在之前工作中得到重视的变量一旦制度影响被控制住,就会变得不显著。

La Porta等人(1999)强调了殖民地的起源(主要殖民国的身份)是当前制度的决定因素的重要性。

如David ndes(1998)强调,殖民地国家的身份也有影响,因为这可能在文化上产生了影响。

表5中的列(1)和列(2),我们加入了英国和法国的殖民虚拟变量(其他国家的殖民地是省略组)。

这对结果的影响很小。

而且,法国虚拟变量在第一阶段被估计为0,而英国虚拟变量是正的,轻微显著。

所以,就如La Porta等人(1998)建议的,英国殖民地看似有更好的制度,但是比起在不控制在制度发展对移民死亡率的影响的样本中,这种影响小的多也弱得多。

所以,看起来在其他研究中英国殖民地被发现本质上表现得更好,很大程度上因为英国殖民的是那些可以移民的地方,而且这使得英国殖民地继承了更好的制度。

为了进一步研究这个问题,列(3)和列(4)只为英国殖民地估计了我们的基本回归。

它们显示了这个25个英国殖民地的样本中,移民死亡率和制度间,制度和收入间的关系都与我们的基本样本非常相似。

例如制度对收入的影响的2SLS估计,在不控制latitude变量的情况下现在是1.07(s.e.=0.24),在控制的情况下为1.00(s.e.=0.22)。

这些结果证明了殖民者身份不是殖民模式和随后的制度发展的一个重要的决定因素。

Von Hayek(1960)和La Porta等人(1999)也强调了法律渊源的重要性。

在列(5)和列(6),我们控制了legal origin这个变量。

用数学来说我爱你英语作文

用数学来说我爱你英语作文

Mathematics,a language of universality and precision,can be used to express the most profound emotions,such as love.When we say I love you in English,we are conveying a message that is deeply personal and heartfelt.However,when we translate this into the language of mathematics,it takes on a different kind of beauty and depth. Heres how you might express I love you using mathematical concepts and symbols:1.The Infinity Symbol:The infinity symbol is a powerful representation of love because it suggests that the feeling is boundless and eternal.In a mathematical love letter,you could write,My love for you is like,it has no end.2.Piπ:Pi is an irrational number,which means it goes on forever without repeating.This could be a metaphor for the endless love one has for another.You might say,My love for you is likeπ,it continues infinitely without repeating.3.The Golden Ratioφ:The golden ratio,approximately1.618,is found in nature and is associated with beauty and balance.It could be used to express the harmony in a relationship.Our love is like the golden ratio,perfectly balanced and beautiful.4.The Pythagorean Theorem a²b²c²:This theorem is a fundamental principle in geometry and could be used to symbolize the foundation of a relationship.Just as a²b²c²,our love is the sum of our individual strengths,creating a strong bond.5.The Fibonacci Sequence:This sequence starts with0and1,and each subsequent number is the sum of the two preceding ones.It could represent the growth of love over time.Our love is like the Fibonacci sequence,growing and evolving with each passing day.6.Eulers Identity eiπ10:This equation is considered one of the most beautiful in mathematics.It combines five fundamental constants e,i,π,1,and0in a simple equation. Our love is an equation as beautiful as Eulers identity,a perfect balance of the complex and the simple.7.The Heart Curve r a1sinθ:This polar equation describes a shape that looks like a heart.Its a direct mathematical representation of love.Our love is like the heart curve,a perfect shape that is uniquely ours.8.The Lorenz Attractor:This is a set of chaotic solutions to the Lorenz system of differential equations,which can be visualized as a butterfly shape.It could symbolize the unpredictable yet beautiful nature of love.Our love is like the Lorenz Attractor, chaotic yet beautiful,always returning to the same beautiful pattern.In conclusion,while I love you in English is a straightforward declaration,using mathematics to express this sentiment adds a layer of complexity and depth that can make the message even more special and meaningful.Its a way to show that love is not just an emotion but also a fundamental part of the universe,as intricate and as infinite as the mathematics that describe it.。

人工智能6作业答案

人工智能6作业答案

人工智能有哪些主要的研究领域?
问题求解 机器学习 自然语言理解 专家系统 模式识别 计算机视觉 机器人学 搏弈 计算智能 人工生命
自动定理证明 自动程序设计 智能控制 智能检索 智能调度与指挥 智能决策支持系统 人工神经网络 数据挖掘和知识发现
第二章 作业
1、常用的知识表示方法都有哪些? 2、请把下列命题表示为谓词公式。
Kasparov • 2000:中科院计算所多主体环境MAGE知识发现系统
MSMiner
人工智能有哪些学派?各自认知观 是什么?
符号主义,又称为逻辑主义、心理学派、计算 机学派,其原理主要为物理符号系统假设和有 限合理性原理。 连接主义,又称为仿生学派、生理学派,其原 理主要为神经网络及神经网络间的连接机制与 学习算法。 行为主义,又称为进化主义、控制论学派,其 原理为控制论及感知-动作型控制系统。
第一章 作业及解答
1、什么是人工智能?发展过程中经历了哪些阶 段?每个阶段列举出其中有代表性的人物。
2、人工智能有哪些学派?各自认知观是什么?
3、人工智能有哪些主要的研究领域?
什么是人工智能?
人工智能(顾名思义):就是用人工的方法在计算 机上实现的智能。 人工智能(学科):人工智能是一门研究如何构造 智能机器或智能系统,使它能模拟、延伸、扩展人 类智能的学科。 人工智能(能力):智能机器所执行的通常与人类 智能有关的智能行为,如判断、推理、证明、识别、 感知、理解、设计、思考、规划、学习和问题求解 等思维活动。
◆ 英国的哲学家、自然科学家Bacon(培根)(1561-1626),系 统地给出了归纳法,强调了知识的作用,著名警句“知识就是力 量”。
◆ 德国数学家、哲学家Leibnitz(莱布尼茨)(1646-1716),把 形式逻辑符号化,从而能对人的思维进行运算和推理,做出了能 进行四则运算的手摇计算机。

()离散数学名词中英文对照

()离散数学名词中英文对照
中文名集合元素严格定义成员外延原理泛集全集空集子集文氏图并交相对补集绝对补集补集对偶性幂等律组合律交换律分配律同一律对合律求补律对偶原理有限集计算原理类幂集子类子集合命题命题计算语句复合子语句合取析取否定真值表重言式矛盾逻辑等价命题代数逻辑蕴涵关系有序对英文set中文名合成函数可逆函数一一对应内射满射双射基数度基数图论多重图顶点无序对边相邻的端点多重边环子图生成子图平凡图入射孤立点连通性通路长度简单通路圈回路连通的连通分支距离欧拉图欧拉链路哈密顿图哈密顿回路货郎行程问题完全图正则图偶图树图加权图同构图同构同胚的平面图英文名compositionfunctionelementinvertiblefunctionwelldefinedonetoonecorrespondencememberinjectiveprincipleofextensionsurjectiveuniversalsetbijectiveemptysetnullsetsubsetcardinalitycardinalnumbervenndiagramgraphtheoryunionmultigraphyintersectionvertixpointnodeunorderedpairrelativecomplementabsolutecomplementedgecomplementadjacentdualityendpointidempotentlawsmultipleedgeassociativelawsloopcommutativelawssubgraphdistributivelawsgeneratedsubgraphidentitylawstrivialgraphinvolutionlawsincidentcomplementlawsisolatedvertexprincipleofdualityconnectivityfinitesetwalkcountingprinciplelengthclasschaintrailpathpowersetsubclasscyclesubcollectionconnectedpropositionconnectedcomponentpropositioncalculusdistancestatementeuleriangraphcompoundeuleriantrailsubstatementhamilt

符号数学概念或为人类独有

符号数学概念或为人类独有

符号数学概念或为人类独有
近日刊登在美国《国家科学院院刊》上的一项新研究称,人类和非人类动物都拥有不通过计算而估计出一组物品数量的能力,但是符号数学的概念却是人类独有的。

这种估算能力依赖于一种近似数系统(ANS)的作用,之前有研究显示,ANS是数量表征的一个大的、更加普遍的系统的一部分。

并且科学家们指出,人类的数学能力可能与我们和动物共享的非语言数量感有联系,虽然人类和动物都具有估算一组物体的数量和尺寸而不需要计数或测量的能力,但是,人类在数学上有其独特的能力——只有人类能够学会符号数学的概念和操作。

为了探索人类是如何进化出正规数学能力的,美国埃默里大学心理系的Stella Lourenco及其同事们招募了65名大学生志愿者,让他们进行了一组非语言数量与尺寸估计任务,以及高等代数和几何的标准化测试。

研究结果显示,那些在数量估计任务上表现出色的受试者也在高等代数测试上表现突出,并且那些在估计相对尺寸任务上做得最好的受试者在几何测试上得到了最高分。

研究人员表示,即便在考虑到一般智力的差异之后,这种相关性仍然很强。

参与该研究的科学家指出,新研究成果揭示出数字精度促进了高等代数的独特变化,而累积面积精度则有助于几何学的独特进化。

这些结果是建立在不断增长的证据的基础之上的,即用于复杂算数和符号数学的神经回路是与数量和尺寸的粗糙估算表现相互联系的。

但是这组作者也指出,尚不清楚数学优秀是否以个人在估计方面的能力为基础,也不知道接触正规数学是否会改善非符号估计的能力。

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Willy Hereman, Jan A. Sanders, Jack Sayers, and Jing Ping Wang
This paper is dedicated to Ryan Sayers (1982-2003) Abstract. Algorithms for the symbolic computation of conserved densities, fluxes, generalized symmetries, and recursion operators for systems of nonlinear differential-difference equations are presented. In the algorithms we use discrete versions of the Fr´ echet and variational derivatives, as well as discrete Euler and homotopy operators. The algorithms are illustrated for prototypical nonlinear lattices, including the Kac-van Moerbeke (Volterra) and Toda lattices. Results are shown for the modified Volterra and Ablowitz-Ladik lattices.
c 2003 Willy ILLY HEREMAN, JAN A. SANDERS, JACK SAYERS, AND JING PING WANG
and both theories can be formulated in terms of complexes. The same applies for the formulation in terms of Lie algebra complexes in [W98]. This allows one to translate by analogy the existing algorithms immediately (although complications arise when there is explicit dependence on the space variable in the discrete case). One of the more useful tools following from the abstract theory is the homotopy operator, which is based on scaling vectorfields, and goes back to Poincar´ e in the continuous case. This operator allows one to directly integrate differential forms and can be straightforwardly implemented in computer algebra packages, since it reduces to integration over one scaling parameter. The discrete analogue as described in [HM02, MH02] does the corresponding job in the discrete case and we use it to compute fluxes. In this paper we do not explicitly use the abstract framework, yet, it has been a motivating force for the development of our algorithms. The algorithms in this paper can be implemented in any computer algebra system. Our Mathematica package InvariantsSymmetries.m [GH97b] computes densities and symmetries, and therefore aids in automated testing of complete integrability of semi-discrete lattices. Mathematica code to automatically compute recursion operators is still under development. The paper is organized as follows. In Section 2, we give key definitions and introduce the Kac-van Moerbeke (KvM) [KvM75], Toda [T81] and Ablowitz-Ladik (AL) lattices [AL75], which will be used as prototypical examples throughout the paper. The discrete higher Euler operators (variational derivatives) and the discrete homotopy operator are introduced in Section 3. These operators are applied in the construction of densities and fluxes in Section 5. The algorithm for higher-order symmetries is outlined in Section 6. The algorithms for scalar and matrix recursion operators are given in Section 7 and Section 8. The paper concludes with two more examples in Section 9. 2. Key Definitions and Prototypical Examples Definition 2.1. A nonlinear (autonomous) DDE is an equation of the form (2.1) ˙ n = F(..., un−1 , un , un+1 , ...), u where un and F are vector-valued functions with m components. The integer n corresponds to discretization in space; the dot denotes one derivative with respect to the continuous time variable (t). For simplicity, we will denote the components of un by (un , vn , wn , · · · ). For brevity, we write F(un ), although F typically depends on un and a finite number of its forward and backward shifts. We assume that F is polynomial with constant coefficients. If present, parameters are denoted by lower-case Greek letters. No restrictions are imposed on the level of the forward or backward shifts or the degree of nonlinearity in F. Example 2.2. The AL lattice [AL75], (2.2) u ˙n v ˙n = = (un+1 − 2un + un−1 ) + un vn (un+1 + un−1 ), −(vn+1 − 2vn + vn−1 ) − un vn (vn+1 + vn−1 ),
1991 Mathematics Subject Classification. Primary 37J35, 37K10; Secondary 35Q58, 37K05. Key words and phrases. Homotopy operators, conserved densities, fluxes, recursion operators, integrability, differential-difference, DDEs, semi-discrete lattices. This material is based upon work supported by the National Science Foundation under Grant No. CCR-9901929.
1. Introduction The study of complete integrability of nonlinear differential-difference equations (DDEs) largely parallels that of PDEs [AC91, ASY00, W98]. Indeed, as in the continuous case, the existence of sufficiently many conserved densities and generalized symmetries is a predictor for complete integrability. Based on the first few densities and symmetries a recursion operator (which maps symmetries to symmetries) can be constructed. The existence of a recursion operator, which allows one to generate an infinite sequence of symmetries, confirms complete integrability. There is a vast body of work on the complete integrability of DDEs. Consult e.g. [ASY00, HH03] for various approaches and references. In this article we describe algorithms to symbolically compute polynomial conservation laws, fluxes, generalized symmetries, and recursion operators for DDEs. The design of these algorithms heavily relies on related work for PDEs [GH97a, HG99, HGCM98] and work by Oevel et al [OZF93]. There exists a close analogy between the continuous and discrete (in space) cases. As shown in [HM02, MH02], this analogy can be completely formalized
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