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131.
谢颖 《科技与企业》2014,(14):150-151
针对国内外电厂对缆式线型感温的设计要求,突出了线型感温探测的重要性。从光纤感温探测的原理开始,对整套系统进行了结构性研究。主要研究了系统结构、探测光缆、控制器等组件。结合拉曼散射原理,剖析温度变化引起探测光缆的吸收和反吸收效应;强调了光学感温探测系统的应用优势和安装条件等。最后结合实体项目,分析对比了传统感温电缆和光学感温探测系统在实际工程应用中的优缺点,并提出了优化方案,以提高火灾报警系统的工作效率。  相似文献   
132.
针对民航市场对客舱宽带卫星通信的迫切需求,提出了一种基于Ka频段高通量卫星的双模解决方案。研究了系统设计的诸多方面,包括卫星资源选择、网络结构、技术体制和适航性。详细介绍了机载设备的组成和双模工作原理,分析了几个与设计实现密切相关的技术指标。方案设计和技术指标分析结果对实际工程应用有一定的参考价值。  相似文献   
133.
Incident evaluations show that bystanders tend to help: they do not wait for professionals to arrive, but act as required by the situation at hand. In the present study, we investigated how safety awareness (induced before an accident happened) and providing a course of action by emergency services affect helping behavior after witnessing a virtual accident with two victims. The main task of the participants was to arrive at a job interview in time. Safety awareness was manipulated by the specific organization they went to: either promoting safe traffic or healthy living. The results show that all participants were inclined to help. Participants who were primed towards safe traffic more often called the emergency number, but talked to the victim less often. Participants who had received specific courses of action moved the victim less often. In all, the results clearly indicate the value of effective risk communication (before an event occurs) and crisis communication (after an event has occurred), as both types of information improve the quality of actual helping behavior at the scene.  相似文献   
134.
We discuss the theoretical rationale for central bank communication about future policy rates, either as part of inflation targeting or in the form of forward guidance. We also summarize both actual central bank communication about future policy rates and empirical evidence on the effectiveness of these types of communication. We argue that there is a disconnect between the theory and practice of forward guidance, as theory assumes commitment on the part of the central bank, while in practice central banks generally do not commit. Future theoretical research on forward guidance should therefore take the absence of commitment by central banks into account.  相似文献   
135.
冷链物流“最后一公里”的品质配送,对于实现全程冷链以及提升企业形象有着重要的意义。为了实现冷链物流的快速配送,本文提出了一种基于复杂网络的“最后一公里”物流配送区域划分方法。该方法构建了现实生活中物流配送的复杂网络模型,然后基于两阶段的LinkRank社区发现算法实现了物流配送区域的划分,最后建立了一套完善的物流配送体系。该体系明确了配送中转站以及配送点所覆盖的区域,这些区域所包含的社区物流关系紧密、易于配送。本文通过案例研究,验证了方法的有效性,最终方案可有效提高“最后一公里”的配送效率和降低物流成本。  相似文献   
136.
DSGE pileups     
The sampling distribution of estimators for DSGE structural parameters tends to be non-normal and/or pile up on the boundary of the theoretically admissible parameter space. This calls into question both the reliability of asymptotic approximations and the presumption of correct specification. This paper seeks to develop a conceptual framework for understanding how these phenomena arise, and to provide pragmatic methods for dealing with them in practice. The results are presented in three examples and a medium scale DSGE model.  相似文献   
137.
I consider the possibility that respondents to the Survey of Professional Forecasters round their probability forecasts of the event that real output will decline in the future, as well as their reported output growth probability distributions. I make various plausible assumptions about respondents’ rounding practices, and show how these impinge upon the apparent mismatch between probability forecasts of a decline in output and the probabilities of this event implied by the annual output growth histograms. I find that rounding accounts for about a quarter of the inconsistent pairs of forecasts.  相似文献   
138.
139.
The communication that Destination Management Organizations (DMOs) address to destination stakeholders plays a central role in attracting attention and resources for sustainable destination development and disclosing the efforts made to be a sustainable territory. There has been extensive analysis on the role of official tourism websites that addresses both DMO's internal and external stakeholders. However, less exploration is available on the relationship between the contents disclosed through tourism websites and the strategic positioning of the destination. This study empirically examines that link with a focus on ‘green/sustainable/responsible' travel. Results show a positive association between the orientation to sustainability in online communication and both sustainable regulation of the tourism sector and tourism development. In contrast, there is no significant association with destination size, tourism maturity and pricing policies.  相似文献   
140.
International Communication plays an important role in our society. Agenda setting theory emerges from communications studies and focuses on mass media influence on setting political agenda.The theory explains the correlation between the rate at which media cover a story and the extent that people think that this story is important. The media has become a strong barrier of communication between families and the outside world.  相似文献   
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