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991.
郭明星 《计算机光盘软件与应用》2010,(16)
本文介绍了以太环网原理、组网方式及特点,并着重介绍了以太环网在城域网中的组网方式及应用配置、以太环网的优越性. 相似文献
992.
郭艳蕊 《计算机光盘软件与应用》2010,(14)
高职高专教育已经成为当前教育的一个主流,国家一直鼓励发展高职高专职业技术教育.在计算机教育教学过程中应该采取适合自己院校发展的手段,从而适应职业教育的需要.本文从八个方面分别阐述了高职高专计算机教育的教学手段. 相似文献
993.
国志强 《计算机光盘软件与应用》2010,(9):152-152
本文主要叙述了利用.net和vba实现计算机公共基础自动阅卷系统功能的设计思路和实现过程,解决了无纸化考试问题,提高阅卷效率。 相似文献
994.
本文就远程教学中出现的流媒体技术做了简要说明,并对Windows Media软件中包含的3个组件进行了重点说明。对利用该组件进行课件采集、制作,Media服务器配置,Media Player功能等做了详细介绍,同时也描述了Windows Media的发展前景。 相似文献
995.
996.
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
997.
Lei Guo Xingwei Wang Qingyang Song Weigang Hou Fei Yang 《Information Sciences》2008,178(18):3635-3644
With the development of intelligent optical networks and the general multi-protocol label switching (GMPLS) technique, the seamless convergence between IP network and optical network is no longer be a dream but a practical reality. Similar to the Internet, current optical networks have been divided into multiple domains each of which has its own network provider and management policy. Therefore, the development of multi-domain optical networks will be the trend of new-generation intelligent optical networks, and GMPLS-based survivability for multi-domain optical networks will become a hot topic of research in the future. This paper provides a comprehensive review of the existing survivable schemes in multi-domain optical networks and analyzes the shortcomings of current research. Based on previous studies, we present possible challenges and propose new ideas to design efficient survivable schemes to guide the future work of researchers in multi-domain optical networks. 相似文献
998.
999.
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
1000.
Yi?GongEmail author Wei?Chen Long?Zhang Yun?Zeng Qunsheng?Peng 《The Visual computer》2008,24(2):95-103
In this paper we introduce an approximate image-space approach for real-time rendering of deformable translucent models by
flattening the geometry and lighting information of objects into textures to calculate multi-scattering in texture spaces.
We decompose the process into two stages, called the gathering and scattering corresponding to the computations for incident and exident irradiance respectively. We derive a simplified illumination model
for the gathering of the incident irradiance, which is amenable for deformable models using two auxiliary textures. In the scattering stage,
we adopt two modes for efficient accomplishment of the view-dependent scattering. Our approach is implemented by fully exploiting the capabilities of graphics processing units (GPUs). It achieves visually
plausible results and real-time frame rates for deformable models on commodity desktop PCs. 相似文献