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31.
The ergodic theory and particularly the individual ergodic theorem were studied in many structures. Recently the individual ergodic theorem has been proved for MV-algebras of fuzzy sets (Riečan in Czech Math J 50(125):673–680, 2000; Riečan and Neubrunn in Integral, measure, and ordering. Kluwer, Dordrecht, 1997) and even in general MV-algebras (Jurečková in Int J Theor Phys 39:757–764, 2000). The notion of almost everywhere equality of observables was introduced by Riečan and Jurečková (Int J Theor Phys 44:1587–1597, 2005). They proved that the limit of Cesaro means is an invariant observable for P-observables. In Lendelová (Int J Theor Phys 45(5):915–923, 2006c) showed that the assumption of P-observable can be omitted. In this paper we prove the individual ergodic theorem on family of IF-events and show that each P {\mathcal{P}} -preserving transformation in this family can be expressed by two corresponding P\flat,P\sharp {\mathcal{P}}^\flat,{\mathcal{P}}^\sharp -preserving transformations in tribe T. {\mathcal{T}}.  相似文献   
32.
Product development processes comprise highly creative and knowledge-intensive tasks that involve extensive information exchange and communication among geographically distributed teams. Due to the geographical and institutional separation between the different systems involved in the product lifecycle, product knowledge sharing is becoming a key issue in the information systems of extended enterprises. This paper addresses the issue and challenges of product knowledge traceability during the product development. The aim of this research effort is to enhance the sharing and use of product knowledge acquired during the development process using traceability information.A standardized approach is proposed to trace and share product knowledge and key constructs to support traceability during the product development process are identified and formalized. This research effort is based on the premise that an important step towards achieving product knowledge sharing is providing traceability across various product knowledge elements that are used in product development phases, i.e. design and manufacturing. Two disjointed but complementary case studies illustrating the benefit of traceability are presented. The potential role of traceability is described, first to support the decision making process during engineering change management (ECM), and second to support product-oriented modelling for knowledge sharing and exchanging to meet the quality requirements. The proposed approach has been implemented using the MEGA Suite tool and applied to each of the case studies and could be integrated to PLM systems currently in use.  相似文献   
33.
分析了连铸机改造前和高效改造后新老系统在控制上的特点 ,着重介绍了改造后控制系统硬件和软件特点 ,该系统投运后不仅解决了本连铸机的自动控制 ,而且完成了连铸 热送 轧钢生产线的顺利贯通。  相似文献   
34.
Web service compositions are becoming more and more complex, involving numerous interacting ad-hoc services. These services are often implemented as business processes themselves. By analysing such complex web service compositions one is able to better understand, control and eventually re-design them. Our contribution to this problem is a mining algorithm, based on a statistical technique to discover composite web service patterns from execution logs. Our approach is characterised by a “local” pattern’s discovery that covers partial results through a dynamic programming algorithm. Those locally discovered patterns are then composed iteratively until the composite Web service is discovered. The analysis of the disparities between the discovered model and the initial ad-hoc composite model (delta-analysis) enables initial design gaps to be detected and thus to re-engineer the initial Web service composition.  相似文献   
35.
The present work numerically investigates two-dimensional (2-D) solidification transport phenomena (EM-STP) during continuous casting (CC) process in the absence and the presence of static magnetic fields (SMFs), based on a unified numerical model. For the purpose of controlling vortexes, the electromagnetic brake (EMBR) effects of various SMFs under the given depth of submerged entry nozzle (SEN) and the same casting velocity V0 are investigated. ANSYS software is used to analyze the SMFs that applied to the EMCC process, and then a data-conversion program based on the principle of linear interpolation proposed previously is used to deal with the issue of data-format-matching between FEM and FVM. The simulation results indicate that, an appropriate SMF can effectively suppress the bulk liquid flow in CC-process of steel plate, and with increase of the intensity of applied magnetic fields, the vortexes become weaker and the oscillating amplitude of impinging jet decreases. Based on the knowledge gained from the EMCC-STP analysis and by comparing the results with the applied magnetic fields with those without magnetic fields, it is found that a SMF with |Bmax|=55×10-3 T can meet the need of braking, and consequently improve the quality of casting by reducing the penetration of non-metallic inclusions, as well as avoiding breakout, macro-segregation and crack ultimately.  相似文献   
36.
传统的Web服务框架不支持基于QoS的查询,不能满足用户对服务性能的要求。在传统的SOA框架上增加了QoS代理中心,并提出了两阶段的服务匹配算法。为了克服QoS动态变化的特点,通过QoS代理监控并记录以往运行的服务反馈的QoS值,来综合计算服务的QoS值。给出QoS记录权重随时间衰减因子,并描述了算法。实验表明该方法具有一定的可行性。  相似文献   
37.
制造业绿色发展战略评价   总被引:1,自引:0,他引:1  
制造业在将资源转变为产品的过程中及产品使用和处理过程中,产生的废弃物对环境的影响比较严重,可持续发展能力不强.企业为了生存和发展,适应内外环境变化,赢得竞争优势的关键在于制定一个适合制造业发展的绿色发展战略.本文在阐述绿色发展战略评价的目的和内容的基础上,建立了将制造业的绿色发展战略的技术评价及经济评价相结合的评价理论体系、程序和方法.  相似文献   
38.
以跨学科架构分析与认识城市规划设计空间   总被引:1,自引:1,他引:1  
在城市设计过程中 ,需要首先对设计的对象进行形象化的分析和研究 ,从而形成关于城市环境空间设计的规定性、指导性导则 .为此 ,在城市规划设计中不同领域的人基于各自的学科领域知识及应用背景以不同的角度去审视分析城市空间 ,从而提供城市空间不同层次不同角度的参考信息 .要形成城市设计空间全面、形象、准确、具体的认识 ,以利于城市设计从整体上去把握城市空间 ,这就需要进行多种信息资料整合 ,首先面临的就是从跨学科的角度去认识和把握城市空间 ,将原有信息在跨学科的领域分析中得到更大的发挥 .通过城市可视视觉景观分析、城市光环境分析及城市风环境分析 ,对在不同层面上所提供的城市环境空间信息进行分析 ,从而探讨基于多学科的信息整合、信息再生、信息处理与分析所面临的机遇与挑战 .  相似文献   
39.
The sign languages used by deaf communities around the world represent a linguistic challenge that natural-language researchers in AI have only recently begun to take up. This challenge is particularly relevant to research in Machine Translation (MT), as natural sign languages have evolved in deaf communities into efficient modes of gestural communication, which differ from English not only in modality but in grammatical structure, exploiting a higher dimensionality of spatial expression. In this paper we describe Zardoz, an on-going AI research system that tackles the cross-modal MT problem, translating English text into fluid sign language. The paper presents an architectural overview of Zardoz, describing its central blackboard organization, the nature of its interlingual representation, and the major components which interact through this blackboard both to analyze the verbal input and generate the corresponding gestural output in one of a number of sign variants.  相似文献   
40.
青藏高原腹地的雷电物理特征   总被引:4,自引:5,他引:4  
通过利用大气平均电场仪和快、慢电场变化仪等仪器设备对青藏高原腹地那曲地区的雷电物理特征进行了分析。发现高原雷暴天气过程中发生的闪电与低海拔地区的相比存在许多的特殊性。这些特殊性主要表现在:闪电在短时间内可以引起较大的电场变化,接近±50kV/m;在一次雷暴天 气过程中的短时强降水可以改变大气平均电场的极性,存在着多个FEAWP过程。较多的地闪只有一次回击,占总地闪数的36.3%,地闪回击数最多的可达到17次,平均为4.11次。地闪中正地闪比率较高可以达到32%。对于负地闪继后回击的电场幅度与首次回击的比与其他地区相比非常高,其平均值为1.42,其中最大值为11.64,最小值为0.17。占总数62%的地闪的连续电流发生在首次回击之后,其持续时间绝大多数在60-160ms之间。  相似文献   
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