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941.
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   
942.
外语磨蚀有七大影响因素,文章通过定量和定性分析,探究了存在于高职生中的英语磨蚀现象及其影响因素,阐述了高职英语教学减少和防止英语磨蚀的相应对策。  相似文献   
943.
In this paper, we introduce a new Bayesian approach to explain some market anomalies during financial crises and subsequent recovery. We assume that the earnings shock of an asset follows a random walk model with and without drift to incorporate the impact of financial crises. We further assume the earning shock follows an exponential family distribution to accommodate symmetric as well as asymmetric information. By using this model setting, we develop some properties on the expected earnings shock and its volatility, and establish properties of investor behavior on the stock price and its volatility during financial crises and the subsequent recovery. Thereafter, we develop properties to explain excess volatility, short-term underreaction, long-term overreaction, and their magnitude effects during financial crises and the subsequent recovery. We also explain why behavioral finance theory could be used to explain many of the asset pricing anomalies, but traditional asset pricing models cannot achieve this aim.  相似文献   
944.
This study investigates the impact of low-cost carriers (LCCs) on Saudi Arabia's tourism demand. It also provides an understanding of the relationship between air transport development and tourism development in the Gulf region. The Box–Jenkins SARIMA-X models were employed to model and forecast international tourist arrivals to Saudi Arabia, using monthly international tourist arrivals to Saudi Arabia from July 2010 to December 2015. The forecasting models were significantly accurate, with lower values of MAPE, MAP, and RMSE. The findings suggest that an increase in airline capacity, religious travel, and airline competition are associated with the increasing international tourist arrivals to Saudi Arabia. This also indicates that there is a positive relationship between air transport development and tourism development. Further aviation liberalisation in the Gulf region is discussed to give opportunities for the region's LCCs to increase their share of the increasing air travel demand, thereby enhancing tourism development.  相似文献   
945.
The study used quarterly panel data of 6 years from 2010 to 2015 of all companies listed on both Vietnamese stock markets including the Ho Chi Minh City Stock Exchange and Ha Noi Stock Exchange, and on three leading industries consisting of insurance-banking, foodstuff, and real estate to explore the relationship among four key financial ratios and stock trading volume. Two models, fixed effects model (FEM) and random effects model (REM), with robust standard errors, were applied for this study. The key findings showed that earnings before tax on sales, debt on owner’s equity, and owner’s equity on total assets significantly influenced trading volume.  相似文献   
946.
采用离子球模型研究了强耦合氢等离子体中杂质Be3+的原子结构和光谱性质随离子球大小的变化规律.结果表明,强耦合等离子体的屏蔽效应对其中的原子结构和光谱影响很大,而且不同模型给出的结果有很大的差别;在离子球模型下,类氢的轨道电离能随着屏蔽效应的增强而单调减小,轨道的简并度解除,但是随着屏蔽效应的增强,轨道将二次简并,轨道能级关于角动量发生发转;不同主量子数n两能级之间辐射的光谱随着屏蔽效应的增强先红移而后蓝移,在非相对论情况下,屏蔽效应引起同n轨道能级劈裂,辐射出新的光谱,该光谱随着等离子体效应的增强先蓝移后红移,经过再次简并后继续蓝移,直到不再辐射出光谱为止;轨道之间的重叠积分由于等离子体屏蔽效应先减小而后增大,从而振子强度随着等离子体屏蔽效应的增强先减小而后增大.目前的计算数据与可查的数据非常符合.  相似文献   
947.
利用广西1978—2012年地区生产总值、银行贷款和银行存款的时间序列数据,建立了三者之间动态关系的向量自回归模型(VAR)。研究结果显示:银行贷款和银行存款对地区经济增长有促进作用,并且银行贷款的影响大于银行存款的影响;在10%的显著水平上,地区生产总值与银行贷款构成双向Granger因果关系;在5%的显著水平上,银行存款与地区生产总值之间只存在单向Granger因果关系。据此,提出了广西金融改革发展的政策建议。  相似文献   
948.
捷克福利体系由社会保险、家庭政策和社会救助三部分组成。通过对转型期捷克福利体系三个组成部分实施的改革进行分析得出结论:尽管捷克福利模式没有实施养老金私有化等自由主义倾向明显的改革措施,但总体上仍然向着盎格鲁撒克逊自由主义福利模式转变,国家责任逐渐减少,市场力量逐步增强。结合捷克改革过程中的经验提出对中国养老金改革的一点建议。  相似文献   
949.
The relative importance of permanent versus cyclical shocks to GDP has been found to depend on the presence or absence of a single break in mean growth. We estimate unobserved components models conditional on a trend break having occurred in any specified quarter and use the Bayesian model averaging to combine the conditional estimates. We estimate a break occurred around 2006:1. Allowing for a break significantly reduces estimates of trend variance. However, enough spread remains in the posterior distribution to indicate that available data does not definitively settle the question of the relative importance of trend versus cycle.  相似文献   
950.
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