四川沙坪水电站如何做好PMC的探讨

四川沙坪水电站是我院承接的第一个PMC项目，经过半年多的筹建，建设管理项目部于2006年3月24日正式挂牌。本文以该项目PMC为背景，探讨如何做好PMC。     

工业PC标准开放体系结构数控系统在卧式加工中心上的应用

使用工业PC标准开放体系结构数控系统，进行卧式加工中心电气控制系统的设计，调试及C＋＋语言PMC软件开发，指出NC主机－伺服系统－机床强电－操作面板－手轮－网络－通讯各部分的总体结构，硬件接线方法，模块化的PMC软件开发方法及机电整合调试步骤。     

On conditional diagnosability and reliability of the BC networks

An n-dimensional bijective connection network (in brief, BC network), denoted by X _n , is an n-regular graph with 2 ⁿ nodes and n2 ^n?1 edges. Hypercubes, crossed cubes, twisted cubes, and Möbius cubes all belong to the class of BC networks (Fan and He in Chin. J. Comput. 26(1):84–90, [2003]). We prove that the super connectivity of X _n is 2n?2 for n≥3 and the conditional diagnosability of X _n is 4n?7 for n≥5. As a corollary of this result, we obtain the super connectivity and conditional diagnosability of the hypercubes, twisted cubes, crossed cubes, and Möbius cubes.     

PMC串行通讯接口板的设计

PMC串行接口板是应用在CompactPCI系统载板上和智能板上的小型板卡,它能实现四路RS-232／422通信接口,且支持HDLC／字符同步／异步通信协议。文介绍了PMC接口板的硬件设计原理,指出通过使用CPLD编程来实现发送时钟方向的改变,与以往方法相比,既节省了芯片和PCB空间,又具有灵活性。最后,通过软件调试,证明该串口工作可靠准确。     

Conditional diagnosability of hypermesh optical multiprocessor systems under the PMC model

The hypermeshes are a family of promising optical interconnection topologies for multiprocessor systems. In this paper, the conditional diagnosability of the hypermesh optical multiprocessor systems, under the PMC model, is determined. We derive that the conditional diagnosability of k ⁿ -hypermesh is 4n(k?1)?4k+1, where n≥3 and k≥5. This result shows that the hypermesh optical multiprocessor systems possess strong self-diagnosing abilities.     

多机系统调试诊断关键技术与方法研究

多机系统规模和复杂度的增加，给测试人员带来了新的挑战。分析了多机系统调试阶段和运行阶段便于测试和诊断的软硬件技术，提出了一种基于边界扫描技术的层次化调试网络结构，给出了通过笛卡儿乘积构造（t,k）-可诊断系统的方法以及通过预处理降低诊断难度、加快诊断速度的思想。     

基于PMC标准的四路通用DA板设计实现

本文介绍了一种基于PMC背板标准的四通道通用DA板的设计,采用了Xilinx公司的Spartan3和PLX公司的PCI9656芯片。基于PMC背板标准的设计,使得板卡的应用更加灵活,既可以单独使用,也可以作为母板的一个功能扩展。FPGA增强了DA板对数据进行回放的灵活性,而PCI9656提供了64bit/66M的PCI接口,可以用来进行高速数据交换。通过DA板,可实现对处理后数据的四路模拟输出。     

PMC备份号恢复及CNC系统的通信方法探究

介绍FANUC 0i系列CNC系统实现PMC备份与恢复的方法及其重要性,结合PMC备份与恢复的理论与实践.阐述CNC系统三种通信方法的优缺点,目的在于使数控机床操作工及雏修工程师具备基本的维修知识和技能,及时排除机床故障,合理使用CNC数控设备,使企业获得更高的经济效益.     

Fault diagnosis using partial syndromes: a modified Hopfield neural network approach

This paper presents a modified Hopfield neural network (HNN) for solving the system-level fault diagnosis problem which aims at identifying the set of faulty nodes. This problem has been extensively studied in the last three decades. Nevertheless, identifying the set of all faulty nodes using only partial syndromes, i.e. when some of the testing or comparison outcomes are missing prior to initiating the diagnosis phase, remains an outstanding research issue. The new HNN-based diagnosis algorithm does not require any prior learning or knowledge about the system, nor about any faulty situation, hence providing a better generalisation performance. Results from a thorough simulation study demonstrate the effectiveness of the HNN-based fault diagnosis algorithm in terms of diagnosis correctness, diagnosis latency and diagnosis scalability, for randomly generated diagnosable systems of different sizes and under various fault scenarios. We have also conducted extensive simulations using partial syndromes. Simulations showed that the HNN-based diagnosis performed efficiently, i.e. diagnosis correctness was around 99% when at most half of the test or comparison outcomes are missing, making it a viable alternative to existing diagnosis algorithms.     

曲轴磨床磨削进给和砂轮修整控制的研究与实现

通过研究曲轴曲拐径磨床磨削进给和砂轮修整的工艺过程,对磨床进行数控系统改造,用PLC和NC相结合的方式在不改变原来PLC程序的前提下实现了砂轮修整和磨削进给的控制。