Diagnosis of Multiple Fixture Faults in Multiple-Station Manufacturing Processes Based on State Space Approach

Dimensional quality is one of the most critical challenges in industries, which uses the multistage manufacturing process (MMP) such as assembly and machining for automotive and aerospace industries.According to investigations, fixture faults accounted for 72% of all the dimensional faults. Previous studies focused on only one fault or multiple faults occurred in one station or one fault in multiple stations, but these cases rarely appear in the real manufacturing. This paper presents a method for diagnosis of multiple fixture faults in the multi-station manufacturing process. The proposed method is based on the state space model of the MMP processes, which carries the information of the fixture layout geometry and sensor position. To identify the root cause, three continuous steps were used: a) development of the state space model and the construction of the statistics variables on offline mode, b) measurement of the coordinate measuring machines data on online mode and calculation of the statistics variables, and c) diagnostic algorithm for identifying the root cause. The presented paper integrates the state space model of the manufacturing processes and hypothesis test considering the impact of the measure noises. A case study verifies the proposed method.     

A New Approach of TPM Construction Based on J2810

Trusted platform model （TPM） is special-purpose integrated circuits （ICs） built into a variety of platforms to enable strong user authentication and machine attestation-essential to prevent inappropriate access to confidential and sensitive information and to protect against compromised networks. Existing TPM products have some limitations. This paper adopts J2810TPM Single Chip cryptogram MCU produced by Jetway Company to construct typical TPM after comparing existing TPM products. Finally, an improved construction approach of TPM based on J2810 is proposed.     

Adaptive Lattice Filter Based Approach to Fault Detection in the Absence of a System Model

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A Potential Approach of Internet Worm Propagation Based on P2P

Various kinds of active worms have been plunging into the network flows, which make the Internet security problem more serious. Our research on a potential propagation approach of active worms, P2P-based propagation approach, is given in this paper. To measure the propagating performance of our approach, the SEI （Susceptible-Exposed-Infected） propagation model is presented. It proves that with the idea of pure P2P architecture, worms can be hidden in the early stage of propagation, and then infect most of the hosts in a shorter period. By comparing our SEI propagation model with the Simple Epidemic Model, we observe that the size of a worm is a significant parameter which can affect the propagating performance. When the size of the worm becomes large, our approach can still show an excellent propagating performance.     

A Review of the Application of Computer Vision to the Inspection and Assessment of Textiles Apparent Properties

IntroductionComputervision,alsocalledmachinevision,isthekindoftechnologyusedfortheidentification,trailing,measurementandevaluation,etc.,oftheobjectsthroughthesubstitutionofcameraandcomputerforhumanvision.Stimulatedbyboththerapidprogressofthecomputerindustryandthedevelopmentofvariousdisciplinesofartificialintelligence,suchasimageanalysis,parallelprocessingandneuralnetwork,etc.,computervisionsystemsarebecomingmoreandmorepracticableandbeingusedintheresearchofagreatdealofcomplicatedvisionprocess,h…     

Novel Approach to the Design of Optoelectronic Heterostructures Based on Indium and Copper Sulfides

1 Results Heterostructures,based on ternary CuInS(Se2) chalcogenides and related binary compounds (Cu2-xCh,CuCh,In2Ch3 and InCh; Ch=S,Se) are considered appear to be a matter of choice for producing promising optoelectronic devices.In the present work we propose and consider a very simple way for the formation of sulfide and selenide heterostructures.The main idea is assumes a novel two-stage method of synthesis and nonstoichiometry control for heterostructures of InxS(Se)1-x/Si,CuInS(Se)2/Si and InxS1-x/SiO2.At the first step the hete rostructure is synthesized and its crystallochemical and morphological features are determined.At the second step the fine adjusting of the film nonstoichiometry and its properties to the desired values is realized.K     

Testing Cross-Talk Induced Delay Faults in Digital Circuit Based on Transient Current Analysis

The delay fault induced by cross-talk effect is one of the difficult problems in the fault diagnosis of digital circuit. An intelligent fault diagnosis based on IDDT testing and support vector machines （SVM） classifier was proposed in this paper. Firstly, the fault model induced by cross-talk effect and the IDDT testing method were analyzed, and then a delay fault localization method based on SVM was presented. The fault features of the sampled signals were extracted by wavelet packet decomposition and served as input parameters of SVM classifier to classify the different fault types. The simulation results illustrate that the method presented is accurate and effective, reaches a high diagnosis rate above 95%.     

Fast ZPinch, A New Approach for Promising Fusion Energy

The basic concept of fast Zpinch, and late progress in fast Zpinch plasma research as HEDP and ICF research, especially as an approach for high yield lowcost fusion energy research, are summarized in this paper. The possible technical challenges of fast Zpinchdriven ICF as fusion energy and it application prospect are discussed.     

A New Detection Approach Based on the Maximum Entropy Model

The maximum entropy model was introduced and a new intrusion detection approach based on the maximum entropy model was proposed. The vector space model was adopted for data presentation. The minimal entropy partitioning method was utilized for attribute diseretization. Experiments on the KDD CUP 1999 standard data set were designed and the experimental results were shown. The receiver operating eharaeteristie（ROC） curve analysis approach was utilized to analyze the experimental results. The analysis results show that the proposed approach is comparable to those based on support vector maehine（SVM） and outperforms those based on C4.5 and Naive Bayes classifiers. According to the overall evaluation result, the proposed approach is a little better than those based on SVM.     

弹性波的反射与折射

在Ｈｏｏｋｅ定律基础上研究了各向同性介质中波在自由面的反射及在两种介质分界面上的反射与折射。得出反射液、折射波的性质与入射波的种类、两种介质的性质及入射角的关系。     

弹性波技术在煤巷锚杆支护检测中的应用

根据弹性波法的检测原理及特点,提出利用弹性波技术进行锚杆支护监测.该方法的原理:当锚杆头受到瞬态力激振后,引锚杆头质点振动,并以应力波的形状向锚杆底部传播.在锚杆、混凝土砂浆和围岩所组成的体系中,在锚杆端部发射一定频率的震动作为波源.具有监测周期短,费用低,并可实现三维空间连续、动态监测等特点.     

瞬态瑞利波分析方法在探测地质体结构中的应用

介绍了探测地质体结构的一般方法,重点介绍了爆破地震波的特征及地震波的探测方法.又对最近发展起来的面波勘探技术做了分析,重点论述了瞬态瑞利波频散特性及其应用.在此基础上,实验了一种可以控制的爆破地震波震源,该震源利用水介质的均匀性及各向同性、不可压缩等特点,减少了爆炸冲击波对周围岩体介质的损坏,又保持了爆炸波功率大,能够提供尖锐的脉冲信号,频域范围大的特点,从而改变了爆破地震波震源不能重复和难以总结其规律的状况.利用瑞利波探测技术和可控爆源,对茅坪滑坡体进行了地质体结构探测,并对其地质体的分层特性做了详细分析,与钻孔勘探结果和挖竖井探测结果比较,二者有较好的一致性.说明结合瞬态瑞利波分析方法,该可控震源在地质体结构探测中有实际的应用价值.     

大坝观测资料分析中谐波温度因子的改进及应用

首先从物理,数学的角度,论述了大坝观测资料回归计算模型中谐波温度因子的起源;之后,对其进行了改进,以考虑气温随机项的影响;最后通过对谐波温度因子系数的分析,给出了确定观测效应量滞后于气温时间的计算公式,实际应用表明,改进后不但计算精度有所提高,而且温度分量与时效分量分配也更加合理;同时,应用本文提出的方法可以比较精确地计算出观测效应应量滞后于气温的时间,这些都为正确评价大坝工作性态提供了良好的参考。     

浅谈信号监测网络结构设置及故障处理

本文对信号集中监测网络结构、常见故障进行了分析,同时结合现场实践经验提出一些处理方法,希望通过这些经验帮助维修人员快速、准确地判断信号集中监测通道故障并及时处理,从而保证集中监测系统的良好运用。     

关门山面板堆石坝现场弹性波试验研究

采用击板法和爆破法结合，成功地在关门山水库工地进行了堆石休内弹性波现场测试和坝体脉动观测，得到了坝体的自振特性和坝体内弹性波速分布及相应的经验公式；在与国外同类试验成果以及室内大型动三轴仪试验成果的广泛比较后，给出堆石材料动力变形参数职值的经验范围。     

高密度电法的延时性勘探研究

描述了高密度电阻率法延时性勘探的基本思想,对矿山排土场进行高密度电阻率法延时性的实际勘探.对比高密度电阻率法延时性勘探的成果资料,对电阻率随时间的变化进行工程与环境解释.结果表明高密度电阻率法延时性勘探对于解决未饱和区域水的流动、水位的变化、化学污染物的扩张和堤坝的渗漏等具有较高的准确性.     

超声波法探测混凝土内部缺陷原理及应用

超声波法是混凝土无损检测的主要方法之一。它通过测量超声脉冲波在混凝土中的传播速度、首波幅度和接收信号主频率等声学参数,并根据这些参数及其相对变化,判定混凝土中的缺陷情况（如混凝土内部空洞和不密实区的位置和范围、裂缝深度、表面损伤层厚度、不同时间浇筑的混凝土结合面质量、灌注桩和钢管混凝土等缺陷）。本文应用超声波对测法对北京某立交桥墩缺陷状况进行检测,准确得到异常点分布区域并确定混凝土不密实区域的空间位置。     

导爆管爆轰及药膜脱离分析

本文着重论述了导爆管管壁中超前传播的弹性波的传播特性及对薄膜炸药的剥离作用。指出该弹性波为超声波,它加强了对药膜的剥离。此波到达管壁与膜体分界面时发生反射和折射,使药膜受力变形而粉碎,在药腱与管内空气界面又产生霍普金斯效应等。几种因素的综合效应,形成了爆轰的气固相混合炸药。     

基于DSP的电力系统分散励磁控制及其动模试验

为了解决电力系统励磁控制实际应用中的问题,利用先进的数字信号处理(DSP)技术,结合理论研究,探索了先进的控制手段对于电力系统安全稳定运行性能的改善情况,介绍了改进后的分散非线性励磁控制规律、基于DSP的控制器电路设计和相关的软件算法以及动模试验情况。动模试验结果表明,基于DSP的新型励磁控制器的软硬件完全满足电力系统实时控制的要求,新的分散非线性励磁控制(DNEC)与传统的比例积分微分的PID控制相比对于改善系统的稳定性具有更优的控制性能。