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1.
注塑件CAD建模与CAE智能处理的集成化研究 总被引:5,自引:2,他引:5
CAD/CAE技术的集成化研究是当前的一个研究热点,对于注塑件/模而言,CAD信息向CAE传输中存在信息丢失和少智能问题,而CAE的结果向CAD信息的反馈过程中也存在信息缺乏衔接和少智能化的问题,利用CBR(基于事件的推理)对工艺参数进行智能推理,然后结合推理出的参数值以及CAD中过滤出的信息,输入到CAE进行分析,对CAD中的特征信息与CAE后处理的信息进行合理的匹配,建立对后处理结果的缺陷解释专家系统。重点对工艺参数优选的CBR及后处理的专家解释系统和数据流的流动过程进行了深入的研究,提出CAD/CAE并行环思想,从而方便了注塑件特征造型与CAE智能处理的集成。 相似文献
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The injection molding process is a typical multi-phase batch process. As the filling and packing-holding phases share the same actuator, faults occurring in the actuators may cause serious impact on the performance and running time. Because these two phases are of crucial importance in relation to the final quality of the product, to solve this problem is essentially meaningful. This paper proposes iterative learning fault-tolerant control (ILTFC) in terms of common multi-phase batch processes and then applies it to the injection molding processes. To develop the ILFTC design, the multi-phase batch process is treated as a switched system composed of different dimensional subsystems and then converted to an equivalent two-dimensional (2D) switched fault-tolerant Rosser model. A hybrid fault-tolerant law is then designed based on an average dwell time method. Sufficient conditions and minimum running time guaranteeing the exponential stability under both normal and fault conditions are obtained. Under the proposed control law, the control performance and running time will restore to the previous level before actuator faults occur. The efficiency and merits of the proposed scheme is illustrated by an injection molding process, and results show that it can guarantee the stability and minimum running time whether the process is in normal operation or in case of actuator faults. 相似文献
3.
汪春梅 《自动化与仪器仪表》2012,(6):66-68
为了提高注塑机故障诊断效率,提高企业经济效益,解决诊断人员不足的问题,提出将远程故障诊断系统应用到注塑机故障诊断中。给出了远程诊断的系统框架,基于三层B/S结构的系统模式,采用将子时段PCA、小波包分析和案例推理相结合的技术作为系统的故障诊断技术,有效实现了注塑机的远程故障诊断。 相似文献
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A clonal selection programming (CSP)-based fault detection system is developed for performing induction machine fault detection and analysis. Four feature vectors are extracted from power spectra of machine vibration signals. The extracted features are inputs of an CSP-based classifier for fault identification and classification. In this paper, the proposed CSP-based machine fault diagnostic system has been intensively tested with unbalanced electrical faults and mechanical faults operating at different rotating speeds. The proposed system is not only able to detect electrical and mechanical faults correctly, but the rules generated is also very simple and compact and is easy for people to understand, This will be proved to be extremely useful for practical industrial applications. 相似文献
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Model predictive control of servo motor driven constant pump hydraulic system in injection molding process based on neurodynamic optimization简 总被引:3,自引:0,他引:3
In view of the high energy consumption and low response speed of the traditional hydraulic system for an injection molding machine, a servo motor driven constant pump hydraulic system is designed for a precision injection molding process, which uses a servo motor, a constant pump, and a pressure sensor, instead of a common motor, a constant pump, a pressure pro-portion valve, and a flow proportion valve. A model predictive control strategy based on neurodynamic optimization is proposed to control this new hydraulic system in the injection molding process. Simulation results showed that this control method has good control precision and quick response. 相似文献
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A light-weight software-implemented fault injection (SWIFI) testing approach is introduced, focusing on technical process faults and system faults. The reaction of automated production systems (aPSs) and their programmable logic controller (PLC) software to these faults is tested. In order to tailor the testing approach to the aPS domain in industrial practice, our test generation is based on a classification of possible deviations, i.e. a classification of possible technical process and system faults as the PLC perceives them. As a result, both specification and test execution become more efficient for practitioners. Furthermore, the test specification is tailored for execution on IEC 61131-3 programming environments. In this, the execution of test cases both against simulation or the real aPS, is enabled. 相似文献
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Tobias Müller Volker Piotter Klaus Plewa Markus Guttmann Hans-Joachim Ritzhaupt-Kleissl Juergen Hausselt 《Microsystem Technologies》2010,16(8-9):1419-1423
Powder injection molding is a preferred technology for the production of micro parts or microstructured parts. Derived from the well known thermoplastic injection molding technique it is suitable for a large-scale production of ceramic and metallic parts without final machining. To achieve good surface quality and control the part size and distortions is an important goal to allow mass production. This means that all process steps like part design adjusted for MIM/CIM-technology, appropriate choice of powder and binder components and injection molding simulation to design the sprue are required. Concerning the injection molding itself high quality mold inserts, high-precision injection molding with suitable molding machines like Battenfeld Microsystem50 or standard machine with special equipment like variotherm or evacuation of the molding tool and an adjusted debinding and sintering process have to be available. Results of producing micro parts by powder injection molding of ceramic feedstock will be presented. 相似文献
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为了提高Tennessee-Eastman(TE)过程的故障诊断准确率,本文研究一种学习型伪度量(learning pseudo metric,LPM)代替距离度量的案例检索方法,并建立了TE过程的案例推理(case-based reasoning,CBR)故障诊断模型.首先建立LPM度量准则并对LPM模型进行训练,其次度量目标案例与每一个源案例的相似度,从中检索与目标案例相似的同类案例,再采用多数重用原则从同类案例中决策出目标案例的解,最后通过TE过程的运行数据对该方法的性能进行测试,并与典型的CBR和BP(back-propagation)神经网络和支持向量机等方法进行对比,表明本文方法能有效提高故障诊断准确率,在实际化工过程中具有一定的推广应用价值. 相似文献
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《IEEE transactions on pattern analysis and machine intelligence》2006,32(11):849-867
The injection of faults has been widely used to evaluate fault tolerance mechanisms and to assess the impact of faults in computer systems. However, the injection of software faults is not as well understood as other classes of faults (e.g., hardware faults). In this paper, we analyze how software faults can be injected (emulated) in a source-code independent manner. We specifically address important emulation requirements such as fault representativeness and emulation accuracy. We start with the analysis of an extensive collection of real software faults. We observed that a large percentage of faults falls into well-defined classes and can be characterized in a very precise way, allowing accurate emulation of software faults through a small set of emulation operators. A new software fault injection technique (G-SWFIT) based on emulation operators derived from the field study is proposed. This technique consists of finding key programming structures at the machine code-level where high-level software faults can be emulated. The fault-emulation accuracy of this technique is shown. This work also includes a study on the key aspects that may impact the technique accuracy. The portability of the technique is also discussed and it is shown that a high degree of portability can be achieved 相似文献
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针对运载火箭系统众多,故障形式多样,出现故障难以准确定位的特点,研究了一种基于MIL-STD-1553B总线(下称1553B总线)的故障诊断和故障注入方法,采用故障树分析法确定失效故障链,实时诊断和预测系统故障;由于实际的系统故障数据较少,通过失效机理分析获得运载火箭的故障库,采用1553B总线对系统注入特定故障;在运载火箭地面故障诊断与注入系统中,原有的拓扑结构维持不变,故障诊断系统作为1553B总线监视器,故障注入系统作为1553B总线的远程终端,并与运载火箭的众多子系统互联,通过总线耦合器连接火箭外部的发射控制平台;最后通过基于实际工程型号开发的故障诊断平台和故障注入平台进行了测试,测试结果表明具有满意的故障覆盖率。 相似文献
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本文针对一类典型的注塑工业过程系统, 研究了注塑填充过程中产生的熔体流动速度最优跟踪控制问题,
提出了一种基于控制参数化的计算最优反馈控制器设计方法以实现注塑过程中熔融聚合物流动前沿位移的最优跟
踪控制, 进而达到改善注塑零件性能的高效生产目标. 首先, 面向注塑工艺复杂生产过程建立了动态过程系统数学
模型, 提出了注塑机内部熔融聚合物流动前沿位置的动态最优跟踪控制问题; 其次, 设计了一种多级反馈控制律, 通
过控制参数化方法将控制反馈核进行了参数化表示, 将控制器设计问题转化为一序列最优参数决策问题; 然后, 通
过状态灵敏度方程分析方法, 求解出了目标函数及约束条件关于决策变量参数梯度信息的显式表达式, 并基于所提
供的梯度信息结合序列二次规划算法进行了高效优化迭代求解; 最后, 通过实验仿真验证了本文所提出的最优反
馈控制器设计方法的可行性和有效性. 相似文献
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John Hunt 《Expert Systems》1997,14(1):15-23
Software debugging (the diagnosis and repair of faults in software) can be a difficult and time consuming problem. In many cases a problem which can take an inexperienced developer a long time to correct can be quickly identified and corrected by a more experienced one. This is often because they have seen that problem (or a similar one) before. In this paper we present a system (called WATSON) which automatically constructs an explanation of the fault and a repair strategy from a library of partial repair models. This system exploits Case Based Reasoning (CBR) technology to perform this construction. The paper introduces the concepts behind CBR before going on to describe the components of the WATSON system. It then illustrates, by example, how WATSON constructs a diagnosis and repair model from the case databases. 相似文献
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The resources allocated for software quality assurance and improvement have not increased with the ever-increasing need for
better software quality. A targeted software quality inspection can detect faulty modules and reduce the number of faults
occurring during operations. We present a software fault prediction modeling approach with case-based reasoning (CBR), a part
of the computational intelligence field focusing on automated reasoning processes. A CBR system functions as a software fault
prediction model by quantifying, for a module under development, the expected number of faults based on similar modules that
were previously developed. Such a system is composed of a similarity function, the number of nearest neighbor cases used for
fault prediction, and a solution algorithm. The selection of a particular similarity function and solution algorithm may affect
the performance accuracy of a CBR-based software fault prediction system. This paper presents an empirical study investigating
the effects of using three different similarity functions and two different solution algorithms on the prediction accuracy
of our CBR system. The influence of varying the number of nearest neighbor cases on the performance accuracy is also explored.
Moreover, the benefits of using metric-selection procedures for our CBR system is also evaluated. Case studies of a large
legacy telecommunications system are used for our analysis. It is observed that the CBR system using the Mahalanobis distance
similarity function and the inverse distance weighted solution algorithm yielded the best fault prediction. In addition, the
CBR models have better performance than models based on multiple linear regression.
Taghi M. Khoshgoftaar is a professor of the Department of Computer Science and Engineering, Florida Atlantic University and the Director of the
Empirical Software Engineering Laboratory. His research interests are in software engineering, software metrics, software
reliability and quality engineering, computational intelligence, computer performance evaluation, data mining, and statistical
modeling. He has published more than 200 refereed papers in these areas. He has been a principal investigator and project
leader in a number of projects with industry, government, and other research-sponsoring agencies. He is a member of the Association
for Computing Machinery, the IEEE Computer Society, and IEEE Reliability Society. He served as the general chair of the 1999
International Symposium on Software Reliability Engineering (ISSRE’99), and the general chair of the 2001 International Conference
on Engineering of Computer Based Systems. Also, he has served on technical program committees of various international conferences,
symposia, and workshops. He has served as North American editor of the Software Quality Journal, and is on the editorial boards
of the journals Empirical Software Engineering, Software Quality, and Fuzzy Systems.
Naeem Seliya received the M.S. degree in Computer Science from Florida Atlantic University, Boca Raton, FL, USA, in 2001. He is currently
a Ph.D. candidate in the Department of Computer Science and Engineering at Florida Atlantic University. His research interests
include software engineering, computational intelligence, data mining, software measurement, software reliability and quality
engineering, software architecture, computer data security, and network intrusion detection. He is a student member of the
IEEE Computer Society and the Association for Computing Machinery. 相似文献
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Romy Müller Laura Ullrich Ann‐Kathrin Dessel Amelie Bengsch Sebastian Heinze Tobias Müller Lukas Oehm 《人机工程学与制造业中的人性因素》2019,29(1):44-62
In the processing industry, frequent faults call for assistance in diagnosis, and case‐based reasoning (CBR) can provide solutions applied by other operators in the past. This study investigated whether salient case ratings promote an uncritical acceptance of solutions. In 2 experiments, subjects diagnosed faults with a simulated CBR system, and ratings were presented in graphical or verbal format. In most trials, the case with the highest rating provided the correct solution, while in catch‐trials, it did not. Graphical ratings were hypothesized to speed up solutions but discourage cross‐checking and lead to errors in catch‐trials. These hypotheses were not confirmed, even though Experiment 2 maximized the incentive of relying on case ratings. While graphical ratings led subjects to start with the most highly rated case, they did not impair situation analysis and accuracy. The results suggest that during fault diagnosis people are not easily misled into overtrusting a CBR system. 相似文献
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Ching-Piao Chen Ming-Tsan Chuang Yun-Hsiang Hsiao Yung-Kuang Yang Chih-Hung Tsai 《Expert systems with applications》2009,36(7):10752-10759
This paper deals with the application computer-aided engineering integrating with statistical technique to reduce warpage variation depended on injection molding process parameters during production of thin-shell plastic components. For this purpose, a number of Mold-Flow analyses are carried out by utilizing the combination of process parameters based on three level of L18 orthogonal array table. In the meantime, apply the design of experiments (DOE) approach to determine an optimal parameter setting. In addition, a side-by-side comparison of two different approaches of simulation and experimental is provided. In this study, regression models that link the controlled parameters and the targeted outputs are developed, and the identified models can be utilized to predict the warpage at various injection molding conditions. The melt temperature and the packing pressure are found to be the most significant factors in both the simulation and the experimental for an injection molding process of thin-shell plastic parts. 相似文献