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101.
FMM人工神经网络在模式识别和分类中具有独特的优势,D—S证据理论在多传感器决策融合上具有优势。提出了一种FMM神经网络与D—S证据理论相结合的多传感器数据融合目标识别方法,给出计算机仿真结果,表明该方法可以克服单一传感器ATR系统的局限性,提高对目标的识别率和系统的容错性。 相似文献
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中国教育和体育的改革、素质教育、“健康第一”教育思想的确定,推动着学校体育的发展。上海交通大学开展了高校体育战略和跨越式发展的理论研究,并进行了长达6年多时间的体育课程体系整体性、立体化运作模式的改革实践,构建了纵向理论指导体系,进行了横向四条主线的一系列改革研究,走上了一条高校体育改革、创新、发展的新路。 相似文献
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以神农湖大桥为背景,对大桥的方案构思、总体设计,以及索塔、主梁、斜拉索、锚固构造等主要结构进行介绍.接着,介绍了基于CATIA的索塔BIM正向设计过程,包括:索塔外形、锚固构造在设计过程中对参数化的运用,并简要说明了三维空间索塔结构二维图纸的表达方法.然后,对桥梁结构进行了整体静力分析和局部分析.结果表明,桥梁结构设计合理,验算结果满足要求.最后,介绍了该桥的施工方案.其研究成果可为同类桥梁的设计、计算提供建议和参考. 相似文献
105.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(7):992-1015
We set out to answer the question: At what hitch angle does it become impossible for a vehicle and trailer to continue to backing up without getting into a jackknife? Jackknifing during backing up of trailers occurs when the hitch angle increases to a point such that the vehicle and trailer fold together about the hitch point like a jackknife. If the backward motion is continued, the jackknife effect progressively worsens, until the vehicle and trailer are in physical contact with each other. Jackknifing can result in traffic disruptions and wasted time, and can potentially cause damage or personal injury. Our goal is to analytically determine the ‘critical hitch angle’ (θcr), the hitch angle threshold beyond which a continued reverse motion causes an inescapable jackknifing. In this paper, we provide a formal definition of θcr for slow backing up of vehicle–trailer systems on a level solid surface, beyond which the vehicle must stop backing up and revert to forward motion in order to escape from jackknifing. The critical hitch angle is sub-categorised into Absolute (θcr, a) and Directional (θcr, d) critical hitch angles depending on the operating constraints and vehicle steering objectives. One solution for θcr is posed as a numerical solution to the steady-state conditions of the dynamic equations. The effects of such hitch angle limitations are demonstrated through simulation. Also, a warning system making use of the θcr is proposed. Such warning systems can assist drivers in avoiding jackknifing while backing up a vehicle–trailer system. 相似文献
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随着信息技术的飞速发展,企业信息化也进入了一个新的阶段.如何有效地整合信息资源为客户实现一站式服务是每个企业信息化研究的主题.本文根据调研某国际货运有限公司的信息化现状和需求,提出了一个可行性的解决方案,对未来实施进行了概要设计的描述. 相似文献
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ABSTRACTThe main purpose of this study is to examine how market participants take risks, in other words, what their risk attitude/preference is, and how their risk attitude could be related to the shipping freight and other markets. To address them, we calibrated the risk attitude of participants in shipping freight markets from 2007 to 2013, and provided an example of the application of risk attitude. For market participants, risk attitude/preference has an important role in understanding shipping freight markets and managing risks under uncertainty. However, risk attitude is not directly observable. To achieve this, we applied a framework that consists of structural model and calibration with market data. We interpreted risk attitude and confirmed that a structural break occurred around 2008 for the calibrated risk attitude parameter. The average risk attitude of market participants tended to be more risk-averse after 2010. We conducted an additional analysis to provide an example of the application of calibrated risk attitude, using structural equation modeling to calculate a latent variable that reflected other commodity markets. We compared the risk attitude parameter and the latent variable, and clarified the relationship between the risk attitude parameter and commodity markets. 相似文献