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51.
Due to the advantages of being able to function under harsh environmental conditions and serving as a distributed condition information source in a networked monitoring system, the fibre Bragg grating (FBG) sensor network has attracted considerable attention for equipment online condition monitoring. To provide an overall conditional view of the mechanical equipment operation, a networked service-oriented condition monitoring framework based on FBG sensing is proposed, together with an intelligent matching method for supporting monitoring service management. In the novel framework, three classes of progressive service matching approaches, including service-chain knowledge database service matching, multi-objective constrained service matching and workflow-driven human-interactive service matching, are developed and integrated with an enhanced particle swarm optimisation (PSO) algorithm as well as a workflow-driven mechanism. Moreover, the manufacturing domain ontology, FBG sensor network structure and monitoring object are considered to facilitate the automatic matching of condition monitoring services to overcome the limitations of traditional service processing methods. The experimental results demonstrate that FBG monitoring services can be selected intelligently, and the developed condition monitoring system can be re-built rapidly as new equipment joins the framework. The effectiveness of the service matching method is also verified by implementing a prototype system together with its performance analysis.  相似文献   
52.
大国的经济外交时代已然到来,而外商直接投资在中国实现工业化和经济发展的过程中起着至关重要的作用。因此,应从中国自身的区域一体化协议的发展特点出发,将外商直接投资因素包含到制定区域经济一体化的战略过程中去,在此基础上研究并制定适合中国的区域一体化协议发展战略,主要是:有选择地开展与发达国家的区域一体化谈判,加强与西亚地区的区域经济合作和在区域一体化协议中重点突出服务业投资自由化。  相似文献   
53.
Noticeable and comprehensible eco-labels are needed to promote sustainable products. So far, researchers have mostly studied consumers' evaluations of eco-labels, without analyzing eco-label's visual complexity. Through two experimental studies this paper proposes that consumers' evaluations of sustainable products increase when zoom-in feature provided in online stores, and they are labelled through eco-labels that have high design and low feature complexity due to increased perceptual fluency. The findings demonstrate that while design complexity increases consumer product evaluations due to increased perceptual fluency, feature complexity increases - instead of decreases – consumers' evaluations due to conceptual – and not perceptual – fluency. Consequently, it is advised to design and adapt eco-labels easy-to-understand, visually eye-catching and highly visible (i.e., in large size) to enhance ease of processing and increase product evaluations.  相似文献   
54.
This paper examines how movie producers recruit directors in the preproduction phase as mutual choices in a two-sided matching model. It conceptualizes that movie attributes and filmmaker characteristics determine the matching outcomes (“who directed which movie”) and in turn indirectly affect movie box office. We exploit a dataset of 4,807 feature films from 1990 to 2010 to examine empirically the complementarities between the movie/producer side and the director side in terms of movie budget, filmmaker track records and social relations. A series of simulations suggest that social relations facilitate positive assortative matching. Further simulation analyses are conducted to quantify the financial implications of movie–director mismatches, as well as the indirect effects of production budget and producer characteristics. The simulation results show that: a) the financial implications of having a mismatched director can be substantial; and b) the indirect effect of production budget and producer characteristics affect movie box office in an interactive manner. These findings can help filmmakers to better understand the financial impacts of movie–director choices and make more informed decisions at the early phase of preproduction.  相似文献   
55.
The European economic integration leads to increasing mobilityof factors, thereby threatening the stability of social transferprograms. This article investigates the possibility to achieveby means of voluntary matching grants both the optimal allocationof factors and the optimal level of redistribution in the presenceof factor mobility. We use a fiscal competition model a la Wildasin(1991) in which states differ in their technologies and preferencesfor redistribution. We first investigate a simple process inwhich the federal authority progressively raises the matchinggrants to the district choosing the lowest transfer and alldistricts respond optimally to the resulting change in transfersall around. This process is shown to increase efficiency ofboth production and redistribution. However, it does not guaranteethat all districts gain, nor that an efficient level of redistributionis attained. Assuming complete information among districts,we derive the willingness of each district to match the contributionof other districts and we show that the aggregate willingnessto pay for matching rates converges to zero when both the efficientlevel of redistribution and the efficient allocation of factorsare achieved. We then describe an adjustment process for thematching rates that will lead districts to the efficient outcomeand guarantee that everyone will gain. (JEL Classification:H23, H70)  相似文献   
56.
Abstract. During the last decade, many Western economies reformed their welfare systems with the aim of activating welfare recipients by increasing welfare‐to‐work programmes (WTWP) and job‐search enforcement. We evaluate the short‐term effects of three important German WTWP implemented after a major reform in January 2005 (‘Hartz IV’), namely short training, further training with a planned duration of up to three months and public workfare programmes (‘One‐Euro‐Jobs’). Our analysis is based on a combination of a large‐scale survey and administrative data that is rich with respect to individual, household, agency level and regional information. We use this richness of the data to base the econometric evaluation on a selection‐on‐observables approach. We find that short‐term training programmes, on average, increase their participants' employment perspectives. There is also considerable effect heterogeneity across different subgroups of participants that could be exploited to improve the allocation of welfare recipients to the specific programmes and thus increase overall programme effectiveness.  相似文献   
57.
利用UG参数化特征造型技术进行涡旋盘设计,在分析涡旋压缩机工作原理的基础上,对涡旋盘参数化建模进行了研究。在UG软件环境下利用参数化建模技术完成了涡旋压缩机实体模型并进行了运动仿真,模型完全满足参数化设计的要求,为涡旋压缩机系列化设计提供了条件。从而提高了产品设计的质量,降低了设计人员的劳动强度。  相似文献   
58.
SIFT算法是众多图像匹配算法中被广泛应用的一种,其具有良好的尺度、光照和空间旋转不变等特征。文章介绍了SIFT算法的4个主要步骤,并将该算法应用到多色二值压缩算法中,提高了压缩效率,缩小了压缩后的存储空间。  相似文献   
59.
地域文化是期刊美术工作者可以深度挖掘的艺术宝藏。文章以《农村新技术》杂志为例,分析了期刊美术设计引入地域文化的重要性,并从突出地方特色、抓典型、求真实等方面作了较全面的论述,说明引入地域文化资源和自然资源对构筑农业科技期刊特色品牌、扩大期刊的知名度和传播力、提升中华文化的世界影响力之意义重大。  相似文献   
60.
随着经济的高速发展,人口的增加,以及建筑用地的短缺,近年来高层建筑的数量飞速增长,建筑高度和层数不断增加,因此高层建筑火灾发生概率也相应增高。由于高层建筑防火、灭火工作比低层建筑复杂、困难,一旦发生火灾,人员伤亡和财产损失都极为严重。因此,如何解决高层建筑的火灾防控已成为一个社会性的难题。文章列举了高层建筑典型火灾案例,分析了高层建筑火灾的特点,提出了高层建筑火灾防范的技术措施。  相似文献   
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