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JJG (沪) 39-1996 公称口径15mm水表(试行)

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基本信息
标准名称:公称口径15mm水表(试行)
发布日期:
实施日期:2005-10-28
首发日期:
作废日期:
出版日期:
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所属分类: 综合 计量 声学计量 计量学和测量 物理现象 声学和声学测量 有关声学的其他标准
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【英文标准名称】:Industrialcommunicationnetworks-Fieldbusspecifications-Part5-19:Applicationlayerservicedefinition-Type19elements
【原文标准名称】:工业通信网络.现场总线规范.第5-19部分:应用层协议规范.19型元件
【标准号】:IEC61158-5-19-2010
【标准状态】:现行
【国别】:国际
【发布日期】:2010-08
【实施或试行日期】:
【发布单位】:国际电工委员会(IX-IEC)
【起草单位】:IEC/SC65C
【标准类型】:()
【标准水平】:()
【中文主题词】:总线系统;总线(数据处理);电路网络;通信;控制设备;控制系统;控制工艺学;数据通信;数据链层;数据连接系统;数据处理;数据设备;数据传送;定义;数字数据;数字工程;数字信号;电子数据处理;电气工程;电子仪器;电子系统;现场总线;制导系统;工业设施;信息交换;信息处理;信息技术;接口;接口(数据处理);链路层;开放系统互连;OSI;物理层;过程控制;过程控制工程;过程控制系统;协议规范;协议;信号;传输媒质;传输协议
【英文主题词】:Bussystems;Buses(dataprocessing);Circuitnetworks;Communication;Controlequipment;Controlsystems;Controltechnology;Datacommunication;Datalinklayers;Datalinksystem;Dataprocessing;Dataservices;Datatransfer;Definitions;Digitaldata;Digitalengineering;Digitalsignals;EDP;Electricalengineering;Electronicinstruments;Electronicsystems;Fieldbus;Guidancesystems;Industrialfacilities;Informationinterchange;Informationprocessing;Informationtechnology;Interfaces;Interfaces(dataprocessing);Linklayers;Opensystemsinterconnection;OSI;Physicallayers;Processcontrol;Processcontrolengineering;Processcontrolsystems;Protocolspecification;Protocols;Signals;Transmissionmedia;Transmissionprotocol
【摘要】:Thefieldbusapplicationlayer(FAL)providesuserprogramswithameanstoaccessthefieldbuscommunicationenvironment.Inthisrespect,theFALcanbeviewedasa“windowbetweencorrespondingapplicationprograms.”Thisstandardprovidescommonelementsforbasictime-criticalandnon-time-criticalmessagingcommunicationsbetweenapplicationprogramsinanautomationenvironmentandmaterialspecifictoType19fieldbus.Theterm“time-critical”isusedtorepresentthepresenceofatime-window,withinwhichoneormorespecifiedactionsarerequiredtobecompletedwithsomedefinedlevelofcertainty.Failuretocompletespecifiedactionswithinthetimewindowrisksfailureoftheapplicationsrequestingtheactions,withattendantrisktoequipment,plantandpossiblyhumanlife.Thisstandarddefinesinanabstractwaytheexternallyvisibleserviceprovidedbythefieldbusapplicationlayerintermsofa)anabstractmodelfordefiningapplicationresources(objects)capableofbeingmanipulatedbyusersviatheuseoftheFALservice,b)theprimitiveactionsandeventsoftheservice;c)theparametersassociatedwitheachprimitiveactionandevent,andtheformwhichtheytake;andd)theinterrelationshipbetweentheseactionsandevents,andtheirvalidsequences.Thepurposeofthisstandardistodefinetheservicesprovidedtoa)theFALuserattheboundarybetweentheuserandtheapplicationlayerofthefieldbusreferencemodel,andb)SystemsManagementattheboundarybetweentheapplicationlayerandSystemsManagementofthefieldbusreferencemodel.Thisstandardspecifiesthestructureandservicesofthefieldbusapplicationlayer,inconformancewiththeOSIBasicReferenceModel(ISO/IEC7498)andtheOSIapplicationlayerstructure(ISO/IEC9545).FALservicesandprotocolsareprovidedbyFALapplication-entities(AE)containedwithintheapplicationprocesses.TheFALAEiscomposedofasetofobject-orientedapplicationserviceelements(ASEs)andalayermanagemententity(LME)thatmanagestheAE.TheASEsprovidecommunicationservicesthatoperateonasetofrelatedapplicationprocessobject(APO)classes.OneoftheFALASEsisamanagementASEthatprovidesacommonsetofservicesforthemanagementoftheinstancesofFALclasses.Althoughtheseservicesspecify,fromtheperspectiveofapplications,howrequestandresponsesareissuedanddelivered,theydonotincludeaspecificationofwhattherequestingandrespondingapplicationsaretodowiththem.Thatis,thebehavioralaspectsoftheapplicationsarenotspecified;onlyadefinitionofwhatrequestsandresponsestheycansend/receiveisspecified.ThispermitsgreaterflexibilitytotheFALusersinstandardizingsuchobjectbehavior.Inadditiontotheseservices,somesupportingservicesarealsodefinedinthisstandardtoprovideaccesstotheFALtocontrolcertainaspectsofitsoperation.
【中国标准分类号】:M11
【国际标准分类号】:25_04_40;35_100_70;35_110
【页数】:38P.;A4
【正文语种】:英语