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231.
Reliability analysis of modern large-scale systems is a challenging task which could benefit from the jointly exploitation of recent model-based approaches and simulation techniques to flexibly evaluate the system reliability performances and compare different design choices. In this context, RAMSAS, a model-based method which supports the reliability analysis of systems through simulation by combining the benefits of popular OMG modeling languages with wide adopted simulation and analysis environments, has been recently proposed. This paper shows the effectiveness of RAMSAS through a real case study concerning the reliability analysis of an Attitude Determination and Control System (ADCS) of a satellite.  相似文献   
232.
为了实现我厂空调系统节能降耗、方便管理、达到工艺要求、提高经济效益等目标,我们选用Johnson Controls(美国江森自控)之Metasys系统对厂区车间的空调进行自控设计。  相似文献   
233.
The advent of interactive digital platforms has led people to progressively interact on such platforms, urging organizations to create online communities to engage customers with them and with each other to enhance brand loyalty. This study attempts to investigate what motivates customers to engage in these brand communities. Through a questionnaire survey of 430 Facebook users, this study investigates whether and how the unique characteristics (information quality, system quality, virtual interactivity, and rewards) of online brand communities affect customer engagement. The consequent effect of customer engagement on brand loyalty is also examined. This study frames and empirically validates a model for engaging customers with online brand communities on Facebook, considering the moderating role of gender. The Stimulus-Organism-Response paradigm is solicited to justify the theoretical background of this study. The data were analyzed using structure equation modelling. Results reveal that each of the characteristics positively influences customer engagement, with information quality and virtual interactivity bearing the strongest influence. Customer engagement also exhibits a strong positive impact on brand loyalty. This results further reveal that gender gap in the online environment is declining as the impact of all the four characteristics of online brand communities on customer engagement was invariable across male and female members.  相似文献   
234.
本讨论了火箭布雷弹的空中运行规律及数学模型,以及求其数值解的方法。  相似文献   
235.
Recent advances in miniaturization of analytical systems and newly emerging technologies offer platforms with greater automation and multiplexing capabilities than traditional biological binding assays. Multiplexed bioanalytical techniques provide control agencies and food industries with new possibilities for improved, more efficient monitoring of food and environmental contaminants. This review deals with recent developments in planar-array and suspension-array technologies, and their applications in detecting pathogens, food allergens and adulterants, toxins, antibiotics and environmental contaminants.  相似文献   
236.
详细介绍服务器双机技术,分析双机热备技术的主要功能,并根据企业系统的需求,提出双机设计方案,并对系统中双机热备实现细节进行相应的阐述。  相似文献   
237.
江庆  陈臣  杨海明 《低温与超导》2011,39(11):53-55
介绍了某型烟气冷却器的设计思路,主要从结构的紧凑性、制冷系统的匹配等方面给予了阐述,通过实际应用说明了其设计的可行性,证明设计是成功的.  相似文献   
238.
以IaaS为切入点,对国内外IaaS发展状况及特点进行梳理,通过对比分析,总结我国包括IaaS在内的公共云服务发展面临的主要问题,提出推动公共云发展的具体建议,并简要介绍国内产业界为此进行的努力。  相似文献   
239.
In this article, we show the existence of intertwined basins of attraction for a class of prey-predator systems, which improves the extant results by deleting some crucial and hard testing conditions.  相似文献   
240.
A feedback control approach to damp the resonances of a guitar string is considered. A guitar string is tightly stretched and fastened at both its ends. This string is placed in a magnetic field and set to vibrations by passing current through it. A displacement sensor is placed such that the actuator and the sensor are collocated. The linear dynamics characterizing the input/output (supplied current/measured displacement) relationship is identified and a model is fit. It is observed that the model satisfies the negative imaginary condition. An Integral Resonant Controller (IRC) is designed, by exploiting the negative imaginary characteristics, to damp the first five modes of the string. Signal conditioning circuitry associated with the sensor could introduce significant time delays that destroy the negative imaginary property. Here, an IRC is designed even when the system does not exhibit negative imaginary characteristics. The effectiveness these control designs are experimentally validated.  相似文献   
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