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1.
本文从设备管理工作中最为基本的设备采购及设备建档两个方面探讨了如何将GB/T15481-2000《检测和校准实验室能力的通用要求》用于指导检测实验室的设备管理实际工作。  相似文献   
2.
通信网络设计是数字化变电站系统设计的核心内容之一,直接关系到数据传输的实时性和变电站各种功能的实现。文中提出了利用网络仿真平台对变电站通信网络进行设计的构想,分析了在数字化变电站不同的发展阶段,通信网络设计的主要内容和网络仿真平台的主要功能及意义,介绍了其结构和仿真流程,重点讨论了仿真模型、仿真内核、通信分析器等开发过程中需要解决的几个关键问题。  相似文献   
3.
OMAPL138和FPGA的合并单元设计方案   总被引:1,自引:0,他引:1  
提出了一种基于ARM9+DSP双核处理器OMAPL-138和FPGA的合并单元设计方案。给出了该方案的原理框图,以及具体的程序流程图,并在CCS开发环境下完成了软件编程,实现了合并单元按照IEC61850标准规定的格式进行数字量以太网传输。实验结果证明了该设计方案的可行性与正确性,为合并单元的设计提供了一种新的思路。  相似文献   
4.
基于IEC61131-3标准设计一个可编程逻辑控制器(PLC)编辑模块,并给出了主要数据结构和算法的设计。通过测试表明用户界面友好,操作简单,对后续开发具指导意义。  相似文献   
5.
ECU是工程机械电控系统的核心部件,目前国内中高端ECU市场基本被国外厂商所垄断。设计了一款基于XC2287M微控制器的工程机械智能ECU,采用CODESYS软PLC作为编程平台,支持IEC 61131-3定义的5种标准PLC语言进行编程。所设计的ECU拥有丰富的I/O资源和完善的安全保护机制,能够广泛应用于各种工程机械控制系统,打破国外厂商对ECU市场的垄断。  相似文献   
6.
本文分析了工业信息安全威胁和需求,对目前工业信息安全规范做了简要概述,重点介绍了IEC62443工业控制系统信息安全规范,并分析主要国际标准组织对工业信息安全的应对思路,同时对其他国际标准组织或行业协会制定的工业信息安全规范做了简要介绍。  相似文献   
7.
基于IEC 61850的状态监测通信方案应用   总被引:1,自引:1,他引:0  
结合状态监测数据通信,介绍了基于IEC 61850的状态监测建模设计,分析了通信方案中可选的4种模型(数据模型、文件传输模型、报告模型、日志模型),提出了满足要求的合理状态监测通信方案,并对其进行了测试。所选方案将投入智能水电厂工程应用。  相似文献   
8.
Standardisation initiatives (ISO and IEC) try to answer the problem of managing heterogeneous information, scattered within organizations, by formalising the knowledge related to products technical data. While the product is the centred object from which, along its lifecycle, all enterprise systems, either inside a single enterprise or between cooperating networked enterprises, have a specific view, we may consider it as active as far as it participates to the decisions making by providing knowledge about itself. This paper proposes a novel approach, postulating that the product, represented by its technical data, may be considered as interoperable per se with the many applications involved in manufacturing enterprises as far as it embeds knowledge about itself, as it stores all its technical data, provided that these are embedded on a common model. The matter of this approach is to formalise of all technical data and concepts contributing to the definition of a Product Ontology, embedded into the product itself and making it interoperable with applications, minimising loss of semantics.  相似文献   
9.
The objective of this paper is to reduce the development time of a PLC (Programmable Logic Controller) by automating the task of code generation. For this purpose, we applied t-MPSG (Timed-Message Based Part State Graph). The t-MPSG is an extended finite state automata used to model and generate an execution module for a real-time shop floor controller system. In our proposed method, t-MPSG is used to model the formal specification of the controller system that can be translated into textual structure. After the verification of the t-MPSG model, it can be used as an input to the plc-builder tool. The plc-builder tool is an extended version of a conventional MPSG simulator. It can be used to translate the textual structure of the t-MPSG into an IEC standard PLC code. Finally, the generated code can be downloaded to a PLC emulator or a PLC device for the purpose of simulation and execution. The similarity in the hierarchical structure of the t-MPSG and the IEC standard PLC program has made it convenient to transform from one form to another. Furthermore, an illustration of the methodology to auto-generate IEC standard PLC code using t-MPSG is explained with a suitable example. Recommended by Editorial Board member Young Soo Suh under the direction of Editor Jae Weon Choi. This work was partially supported by Defense Acquisition Program Administration and Agency for Defense Development under the contract (UD080042AD). Devinder Thapa is a Postdoc Research Fellow in the Department of Industrial & information systems at Ajou University, Korea. He completed his Ph.D. from Ajou University in Industrial and Information Systems Engineering. His area of research is related to manufacturing automation and intelligent decision support systems. Chang Mok Park is a Professor in the Department of Technology & Systems Management at Induk Institute of Technology. He completed his Ph.D. in 2002 from Ajou University in Industrial Engineering. His research interest is related to manufacturing optimization, discrete event system simulation and signal analysis. Sang C. Park is an Associate Professor in the Department of Industrial & Information Systems Engineering at Ajou University. He received his B.S., M.S., and Ph.D. degrees from KAIST in 1994, 1996, and 2000, respectively, all in Industrial Engineering. His research interests include geometric algorithms in CAD/CAM, process planning, engineering knowledge management, and discrete event system simulation. Gi-Nam Wang is the Head and a Professor in the Department of Industrial & Information Systems Engineering at Ajou University, Korea. He completed his Ph.D. in 1992 from Texas A&M University, in Industrial Engineering. He has worked as Visiting Professor at University of Texas at Austin during 2000–2001. His area of research is related to Intelligent Information & manufacturing systems, system integration & automation, e-Business solutions and image processing.  相似文献   
10.
Efficient identity-based GQ multisignatures   总被引:1,自引:0,他引:1  
ISO/IEC 14888 specifies a variety of digital signature mechanisms to sign messages of arbitrary length. These schemes can be applied to provide entity authentication, data origin authentication, non-repudiation, and data integrity verification. ISO/IEC 14888 consists of three parts under the general title Information technology—Security techniques—Digital signatures. Part II, or ISO/IEC 14888-2 specifies the general structure and the fundamental procedures for the generation and verification of an identity-based signature (IBS) mechanism for messages of arbitrary length. Particularly, the IBS scheme of Guillou and Quisquater (GQ) is described in Clauses 6–8. In this paper, an efficient identity-based multisignature (IBMS) scheme is proposed for the GQ IBS scheme, which allows multiple users using the ISO/IEC 14888-2 standard GQ scheme to generate multisignatures. The scheme is efficient in the sense that both the length and the verification time of the multisignatures are fixed. The proposed ID-based multisignature scheme is also secure against forgeability under adaptive chosen-message attack and adaptive chosen-identity attack in random oracle model.  相似文献   
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