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制造网格中资源管理系统研究 总被引：7，自引：0，他引：7
为实现制造业的资源共享和协同工作, 以开放网格服务架构(OGSA)为系统框架, 以GT3(Globus Toolkit 3.0)为开发工具, 提出了制造网格的概念. 然而, 由于制造资源的复杂性、多样性、特殊性和分散性, 制造网格中的资源管理问题明显比其他网格应用项目困难得多. 因此, 开发了制造网格信息服务(MGIS), 该服务通过有效集成检测查询服务(MDS)和各种类型的资源封装模板, 实现了制造资源的远程封装、注册、发现和监控. 同时, MGIS与GRAM(globus resource allocation manager)共同构建了制造网格的资源管理系统, 解决了制约制造网格应用的瓶颈问题. 最后, 给出了该系统的应用框架, 并通过制造网格试验床中的一个具体应用实例说明了其实际应用过程. 相似文献
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马海珠 《浙江教育学院学报》2004,(5):1-5,22
应用构象统计方法和改进的侧基旋转异构态模型,推导了对称取代基链的均方回转半径特征比《S2》/2xl2公式,可研究聚二甲基硅烷链的柔顺性,根据特征比与链长的关系,得到聚二甲基硅烷链长链特征比值0.94,结果还与聚二甲基硅氧烷链前期计算值作了比较. 相似文献
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基于多Agent的自动工艺实现模型 总被引：2，自引：0，他引：2
近年来 ,产品各个加工过程的集成已经成为研究和工业生产的焦点 .本文提出了一种基于多Agent的自动工艺模型 ,使各个模块更能协调工作 ,达到资源、信息充分共享 相似文献
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Resources publication and discovery in manufacturing grid 总被引：3，自引：0，他引：3
TAO Fei HU Ye-fa DING Yu-feng SHENG Bu-yun ZHOU Zu-de 《浙江大学学报(A卷英文版)》2006,7(10):1676-1682
INTRODUCTION Manufacturing Grid (MGrid) is a new concept proposed to meet the practical demands in the manufacturing industry and is a new technology enabling broad geographical distribution of all sorts of manufacturing resources through the Internet or other specific nets, using grid technology. With the MGrid platform, we can realize common sharing of manufacturing resources including human resources, equipment resources, material resources, applicable software systems, etc., and can … 相似文献
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通过模式进行CIM到PIM的模型转换 总被引：1，自引：0，他引：1
Model driven architecture （MDA） is an evolutionary step in software development. Model transformation forms a key part of MDA. The transformation from computation independent model （CIM） to platform independent model （PIM） is the first step of the transformation. This paper proposes an approach for this transformation with pattern. In this approach, we take advantage of ＂reuse＂ from various standpoints. Feature model is used to describe the requirement of the application. This can help us bring ＂reuse＂ into effect at requirement level. Moreover we use pattern to transform CIM to PIM. This can help us bring ＂reuse＂ into effect at development level. Meanwhile, pattern was divided into four hierarchies. Different hierarchies of pattern are used to help us utilize reuse at different phase of development. From another standpoint, feature model describes the problem of a domain while pattern describe the problem across domains. This can help us reuse the element in and across domains. Finally, the detailed process of the transformation is given. 相似文献
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Based on an analysis of the relationship between electronic business (EB) and collaborative product commerce (CPC), the conception of CPC is illustrated rigorously. Development and classification of manufacturing systems are summarized. System features and goals on each stage of a manufacturing system are investigated. In particular, goals and feature characteristics of CPC manufacturing system are discussed. A figure of relationship between the feature and goal of a CPC manufacturing system is given. A model of CPC manufacturing systems based on a set of five elements including goal, feature, topology, view, and process is proposed. Furthermore, four models of 3D function analysis for PFV, PTV, PTG, and PFG are established. 相似文献
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随着物联网技术的快速发展,窄带物联网NB-IoT拥有广阔的应用前景。目前国内高校的NB-IoT实验室建设相对滞后,为适应“新工科”建设需求,培养新兴物联网技术方面具有创新实践能力、工程应用能力的人才,在建设NB-IoT实验室过程中融入OBE教育理念,构建了多层次、递进式实践教学体系,设计了培养以“问题为导向”的基本技能、以“任务为驱动”的综合实践和以“课题为背景”的工程实践与创新能力的3级课程教学体系。从NB-IoT 3层网络结构模型进行实验室建设,结合实验课程体系模块化设计与实践,建设完整的NB-IoT实验室与课程体系,取得很好的应用成效。 相似文献
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In this paper,a fabrication scheduling problem concerning the production of components at a single manufacturing facility was studied,in which the manufactured components are subsequently assembled into a finite number of end products. Each product was assumed to comprise a common component to all jobs and a unique component to itself.Common operations were processed in batches and each batch required a setup time.A product is completed when both its two operations have been processed and are available.The optimality criterion considered was the minimization of weighted flow time.For this scheduling problem,the optimal schedules were described in a weignted shortest processing time first(WSPT)order and two algorithms were constructed corresponding to the batch availability and item availability,respectively. 相似文献
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Design of general multivariable process controllers is an attractive and practical alternative to optimizing design by evolutionary algorithms （EAs） since it can be formulated as an optimization problem. A closed-loop particle swarm optimization （CLPSO） algorithm is proposed by mapping PSO elements into the closed-loop system based on control theories. At each time step, a proportional integral （PI） controller is used to calculate an updated inertia weight for each particle in swarms from its last fitness. With this modification, limitations caused by a uniform inertia weight for the whole population are avoided, and the particles have enough diversity. After the effectiveness, efficiency and robustness are tested by benchmark functions, CLPSO is applied to design a multivariable proportional-integral-derivative （PID） controller for a solvent dehydration tower in a chemical plant and has improved its performances. 相似文献
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Representations of contemporary rapid prototyping (RP) technologies may not be able to manage and share data processing information based on network. This paper presents a new approach, together with its technical implementation, to solve this problem, and discusses web-based study on RP data processing tecihniques. At present STL files produced by 3D modeling systems contain triangular facet representation of surfaces and have become standard data inputs of RP and manufacturing systems. The paper proposes algorithms for correcting common errors, and optimizes the algorithm of gaps or hole errors leading to open loops in the data structure based on analyses of the rules and errors in the STL file. In addition, effectiveness of the approach is demonstrated by a simple model view example of STL files based on Java 3D technology. 相似文献
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As the idea of simulated annealing （SA） is introduced into the fitness function, an improved genetic algorithm （GA） is proposed to perform the optimal design of a pressure vessel which aims to attain the minimum weight under burst pressure constraint. The actual burst pressure is calculated using the arc-length and restart analysis in finite element analysis （FEA）. A penalty function in the fitness function is proposed to deal with the constrained problem. The effects of the population size and the number of generations in the GA on the weight and burst pressure of the vessel are explored. The optimization results using the proposed GA are also compared with those using the simple GA and the conventional Monte Carlo method. 相似文献
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The selective laser sintering (SLS) technique is introduced. A new type of rapid prototyping material (PCP1) has been developed, which can be used to produce precision casting mould directly and rapidly from a CAD model by the selective sintering of successive layers of PCP1 with a laser beam. In comparison with conventional manufacturing methods, prominent features of this technique include high forming rate, low development cost and good flexibility. The rapid manufacturing process of precision casting mould based on SLS is discussed. 相似文献
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SU Cheng-li WANG Shu-qing 《浙江大学学报(A卷英文版)》2006,7(10):1723-1732
INTRODUCTION In recent years, research on nonlinear model predictive control has attracted significant attention because most practical processes are nonlinear. In industry process control, model predictive controllers based on linear models (LMPC) are often used to control nonlinear systems. When the operating con- ditions undergo significant changes, the performance of LMPC can deteriorate drastically. Under such conditions, predictive control based on nonlinear models (NMPC) shoul… 相似文献
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肖冰 《福建工程学院学报》2014,(2):136-140
为解决目前制造企业面临的“用工荒”难题,需要深入分析影响新生代农民工就业选择行为的影响因素,从而便于找出针对性解决办法。基于对297位新生代农民工的调查数据,运用Logistic模型对新生代农民工城市就业选择行为的影响因素进行了回归分析。基于研究结果,针对性提出了提升中小制造企业就业吸引力的政策建议。 相似文献
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Traditional lapped transform domain excision techniques obtain good performance at the expense of increased processing delay. Extension of transform domain filtering techniques to the lapped biorthogonal transform domain can help solve the problem. By incorporating biorthogonality into the lapped transforms, more flexibility is obtained in the design of windows. Thus transform bases with better stopband attenuation can be generated by designing windows, but not by increasing the overlapping factor. In this paper, a new modulated lapped biorthogonal transform (MLBT) with optimized windows is introduced for efficient compression of multi-tone interfering signal energy. The bit error rate (BER) performance of the receiver employing the proposed MLBT excision technique is analyzed and compared with that of the lapped transform domain excision-based receivers. Simulation results demonstrate the improved performance and increased robustness of the proposed technique. 相似文献
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产品数据模型是产品数据管理中信息集成的基础，本提出了基于产品对象的数据管理方式，在此基础上描述了PDM中的面向对象的产品数据模型。根据产品数据模型提出了基于产品对象的通用数据、设计数据、制造数据3棵树组织产品数据的方法，为现在并行产品设计方式提供了有力的支持。 相似文献
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PAN Peng LU Yan-sheng 《浙江大学学报(A卷英文版)》2007,8(4):529-537
The problem of continuously monitoring multiple K-nearest neighbor (K-NN) queries with dynamic object and query dataset is valuable for many location-based applications. A practical method is to partition the data space into grid cells, with both object and query table being indexed by this grid structure, while solving the problem by periodically joining cells of objects with queries having their influence regions intersecting the cells. In the worst case, all cells of objects will be accessed once. Object and query cache strategies are proposed to further reduce the I/O cost. With object cache strategy, queries remaining static in current processing cycle seldom need I/O cost, they can be returned quickly. The main I/O cost comes from moving queries, the query cache strategy is used to restrict their search-regions, which uses current results of queries in the main memory buffer. The queries can share not only the accessing of object pages, but also their influence regions. Theoretical analysis of the expected I/O cost is presented, with the I/O cost being about 40% that of the SEA-CNN method in the experiment results. 相似文献