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81.
随着社会的发展,信息和文化资源大多来自于图书和网络,而高校图书馆有着丰富的藏书和网络资源,因此,高校图书馆网络资源的共建共享就是科学文化发展的必然结果。那么如何实现网络资源的共建共享,网络资源的共建共享又存在哪些问题,又该如何解决,本文在这里就简单的浅谈一下高校图书馆的资源共享。  相似文献   
82.
This paper deals with the efficient computation of solutions of robust nonlinear model predictive control problems that are formulated using multi-stage stochastic programming via the generation of a scenario tree. Such a formulation makes it possible to consider explicitly the concept of recourse, which is inherent to any receding horizon approach, but it results in large-scale optimization problems. One possibility to solve these problems in an efficient manner is to decompose the large-scale optimization problem into several subproblems that are iteratively modified and repeatedly solved until a solution to the original problem is achieved. In this paper we review the most common methods used for such decomposition and apply them to solve robust nonlinear model predictive control problems in a distributed fashion. We also propose a novel method to reduce the number of iterations of the coordination algorithm needed for the decomposition methods to converge. The performance of the different approaches is evaluated in extensive simulation studies of two nonlinear case studies.  相似文献   
83.
Evidence suggests that transient visual information, such as animations, may be more challenging to learn than static visualizations. However, when a procedural-manipulative task is involved, our evolved embodied cognition seems to reverse this transitory challenge. Hence, for object manipulative tasks, instructional animations may be more suitable than statics. We investigated this argument further by comparing animations with statics using a Lego task shown to university students, by examining three potential moderators of effectiveness: (a) the environment of manipulation (virtual or physical), (b) the quality of visual information (focused or unfocused), and (c) the presence of hands (no hands or with hands). In Experiment 1 we found an advantage of animation over statics, and no differences among the environments. In Experiment 2, we again observed an animation advantage, a small advantage of focused static information compared to unfocused static information, and a positive effect of not showing the hands.  相似文献   
84.
In the thin-film transistor liquid crystal display (TFT-LCD) manufacturing, the development of models to determine product mix and capacity allocation for a multi-stage, multi-site, and multi-generation company is very important. As rapid advancement of the electronic-paper display (EPD) technology, it is a trend of the coexistence of heterogeneous products involving LCD and EPD products. In the case we investigated, the TFT-LCD company merged an EPD company and incorporated their electro-phoretic technologies into their company. Notably, the manufacturing processes of the EPD products do not incorporate the process steps of liquid crystal injection and attachment of color filters. Consequently, to minimize the total cost, it is essential to decide the appropriate product mix and capacity allocation with considerations of the resource consumption of LCD and EPD products simultaneously. In this paper, we present mathematical models to determine product mix and capacity allocation, which involve three subsystems for TFT-LCD process with consideration of net demand, inventory level, yield rates, cost, margin, outsourcing allocation, cycle time, and panel conversion rate. To demonstrate the applicability of the proposed models, we present a real-world case taken from a TFT-LCD company located in the Science-Based Industrial Park at Hsinchu, Taiwan and perform sensitivity analysis to investigate the effect on the optimal solution.  相似文献   
85.
该文对矿用可移动式救生舱进行了分类,对比了各自的优缺点,指出国内厂家和高校均以硬体式救生舱作为主要研究对象;随后着重对此种救生舱的总体构成进行了说明,介绍了过渡舱、生活舱和设备舱的具体功能和内部设备;最后论述了几种固定和安放方式的利弊,指出在实际应用中,应根据所在巷道的地质特点合理选择安置方案。  相似文献   
86.
This study presents a methodology to assess suitability of a site for small scale concentrated solar power (CSP) systems for its energy conversion efficiency and make‐up water requirement. Energy conversion efficiency of CSPs relies not only on the level of direct solar radiation but also on the performance of the cooling system. Regions with high solar potential have to deal with heat rejection at elevated temperatures which causes reduced energy conversion efficiencies due to high condenser temperatures. It is desirable to utilize wet cooling systems as they can achieve temperatures lower than the dry bulb temperature by evaporative cooling. On the other hand, such regions usually lack water resources which deteriorate the sustainable nature of CSP applications. This study combines various available models for both solar resource estimation and cooling systems' performance considering (i) the influence of ambient temperatures, and (ii) the influence of humidity levels. These models are integrated together to analyze the use of dry or wet cooling systems in terms of overall energy output and water consumption at a selected site in northern Cyprus. The model inputs consist of only annual hourly surface weather data and the location of the site of interest. The results show that dry cooling unit at northern Cyprus is capable of saving water about 18.7 ton/MWh while it produces 27% less energy compared to the wet cooling alternative for the representative annual weather data. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
87.
《Planning》2015,(4)
耐盐菌可提高作物产量  相似文献   
88.
《Planning》2015,(4)
以颐红水蜜桃为试材进行果实套袋试验,探讨套袋对果实外观、品质、病虫害、产值的影响。结果表明:套袋果可明显改善果实外观色泽和内在品质,减少病虫果,提高商品果率,增加产值。  相似文献   
89.
《Planning》2015,(3)
目的 评估腹腔脏器病变患者术前经腹超声检查报告并分析超声漏诊及误诊的原因。方法 通过病理工作站导出2013年3月1日至8月31日因腹腔脏器(肝脏、胆囊、胆管、胰腺、脾脏、肾脏、肾上腺和阑尾)病变于北京协和医院进行手术治疗的住院患者病理资料,评估相应超声报告,记录漏、误诊报告信息,分析漏、误诊原因。结果 共评估超声报告1081份,漏、误诊报告58份(5.37%,58/1081),其中肝脏病变6例(5.77%,6/104),均为误诊;胆囊和胆管病变6例(1.30%,6/462),漏诊5例、误诊1例;胰腺病变14例(19.72%,14/71),均为漏诊;肾脏和肾上腺病变20例(6.47%,20/309),漏诊11例、误诊9例;阑尾病变12例(16.00%,12/75),漏诊11例、误诊1例。漏诊结节样病变最大径平均值显著低于误诊病变(P=0.001)。结论 不同腹腔脏器病变因性质、部位、体积以及超声本身的局限性等原因导致超声漏诊或误诊,超声医师在临床工作中应做到全面、仔细、谨慎,了解各腹腔脏器病变的自身特点以及超声显像的局限性,不断积累经验,尽可能避免不必要的错误。  相似文献   
90.
论文从硬件设备、软件服务、数据资源和任务调度等几个方面对美国海军在开发构建全舰计算环境基础设施过程中标准化的设计方法进行深入分析。通过采用标准化的计算、显示、存储等硬件资源并进行整合,提升硬件资源的利用效率和共用水平;开发各个层次的公共应用功能软件并形成标准化的服务,将软件和硬件解耦,达到应用与数据分离,使得基于TSCEI的信息化装备的构建更加快速灵活,开放性更好,可扩展性及升级能力大为增强。标准化在 TSCEI的推行和实施中起着至关重要的作用。标准化设计方法对构建我军新型信息基础设施具有较重要的借鉴作用。  相似文献   
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