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81.
82.
季艳 《计算机光盘软件与应用》2010,(10):177-177
Coreldraw的教学比较注重实际操作能力,与传统科目的教学不同,它更应该以学生为教学的中心。所以在教学过程中要注意教学方式的改变。本文就coreldraw教学中如何做到以学生为中心做简单论述。 相似文献
83.
纪树立 《计算机光盘软件与应用》2010,(12)
任务驱动教学法是建立在建构主义学习理论基础上的教学模式,将知识的学习放置于具体问题解决上来,通过学生自身或小组协作,来完成任务.在学习计算机编程的课程时,使用任务驱动法教学,可以大大提高教学效果,同时又能培养一种良好的团队精神,体现以学生的全面发展为中心的教育思想. 相似文献
84.
On Controllability of Switched Linear Systems 总被引:1,自引:0,他引:1
Zhijian Ji Long Wang Xiaoxia Guo 《Automatic Control, IEEE Transactions on》2008,53(3):796-801
This paper investigates the number of switchings and design of switching sequences for controllability of switched linear systems. Two related results are established. One is a new constructive approach to designing switching sequences. The controllable state set of each switching sequence designed via the approach coincides with the controllable subspace of switched linear systems. The other is a well-estimated value for the minimum number of switchings required for controllability. Each state in the controllable subspace can be steered to origin within this value of switching times. 相似文献
85.
An application of MODIS data to snow cover monitoring in a pastoral area: A case study in Northern Xinjiang, China 总被引:3,自引:0,他引:3
Tian Gang Liang Xing Yuan Liu Wen Long Li Zheng Gang Guo Ji Zhou Ren 《Remote sensing of environment》2008,112(4):1514-1526
Snow is an important land cover on the earth's surface. It is characterized by its changing nature. Monitoring snow cover extent plays a significant role in dynamic studies and prevention of snow-caused disasters in pastoral areas. Using NASA EOS Terra/MODIS snow cover products and in situ observation data during the four snow seasons from November 1 to March 31 of year 2001 to 2005 in northern Xinjiang area, the accuracy of MODIS snow cover mapping algorithm under varied snow depth and land cover types was analyzed. The overall accuracy of MODIS daily snow cover mapping algorithm in clear sky condition is high at 98.5%; snow agreement reaches 98.2%, and ranges from 77.8% to 100% over the 4-year period for individual sites. Snow depth (SD) is one of the major factors affecting the accuracy of MODIS snow cover maps. MODIS does not identify any snow for SD less than 0.5 cm. The overall accuracy increases with snow depth if SD is equal to or greater than 3 cm, and decreases for SD below 3 cm. Land cover has an important influence in the accuracy of MODIS snow cover maps. The use of MOD10A1 snow cover products is severely affected by cloud cover. The 8-day composite products of MOD10A2 can effectively minimize the effect of cloud cover in most cases. Cloud cover in excess of 10% occurs on 99% of the MOD10A1 products and 14.7% of the MOD10A2 products analyzed during the four snow seasons. User-defined multiple day composite images based on MOD10A1, with flexibilities of selecting composite period, starting and ending date and composite sequence of MOD10A1 products, have an advantage in effectively monitoring snow cover extent for regional snow-caused disasters in pastoral areas. 相似文献
86.
Motion capture cannot generate cartoon‐style animation directly. We emulate the rubber‐like exaggerations common in traditional character animation as a means of converting motion capture data into cartoon‐like movement. We achieve this using trajectory‐based motion exaggeration while allowing the violation of link‐length constraints. We extend this technique to obtain smooth, rubber‐like motion by dividing the original links into shorter sub‐links and computing the positions of joints using Bézier curve interpolation and a mass‐spring simulation. This method is fast enough to be used in real time. 相似文献
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As an important technology for predictive maintenance, failure prognosis has attracted more and more attentions in recent
years. Real-time reliability prediction is one effective solution to failure prognosis. Considering a dynamic system that
is composed of normal, deteriorating and unreliable components, this paper proposes an integrated approach to perform real-time
reliability prediction for such a class of systems. For a deteriorating component, the degradation is modeled by a time-varying
fault process which is a linear or approximately linear function of time. The behavior of an unreliable component is described
by a random variable which has two possible values corresponding to the operating and malfunction conditions of this component.
The whole proposed approach contains three algorithms. A modified interacting multiple model particle filter is adopted to
estimate the dynamic system’s state variables and the unmeasurable time-varying fault. An exponential smoothing algorithm
named the Holt’s method is used to predict the fault process. In the end, the system’s reliability is predicted in real time
by use of the Monte Carlo strategy. The proposed approach can effectively predict the impending failure of a dynamic system,
which is verified by computer simulations based on a three-vessel water tank system. 相似文献