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181.
Yunhui Shi Bo Wen Wenpeng Ding Na Qi Baocai Yin 《Multimedia Tools and Applications》2014,70(3):2125-2137
The benefit of using the geometry image to represent an arbitrary 3D mesh is that the 3D mesh can be re-sampled as a completely regular structure and coded efficiently by common image compression methods. For geometry image-based 3D mesh compression, we need to code the normal-map images while coding geometry images to improve the subjective quality and realistic effects of the reconstructed model. In traditional methods, a geometry image and a normal-map image are coded independently. However a strong correlation exists between these two kinds of images, because both of them are generated from the same 3D mesh and share the same parameterization. In this paper we propose a predictive coding framework, in which the normal-map image is predicted based on the geometric correlation between them. Additionally we utilize the strong geometric correlation among three components of normal-map image to improve the predicting accuracy. The experimental results show the proposed coding framework improves the coding efficiency of normal-map image, meanwhile the realistic effect of a 3D mesh is significantly enhanced. 相似文献
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网络安全已经成为了社会热点问题之一.针对网络的安全性和可靠性等问题,从计算机网络安全的定义、存在的问题和防范措施等方面入手,提出了一些看法.只有真正提升网络安全的防范能力,建设安全、稳定的计算机系统,才能满足个人和社会对网络的需要,从而实现安全利用计算机网络信息的目标. 相似文献
184.
针对机龄较长的A320飞机多次重复出现DEU B或DEU B 300 RH等故障信息,难以排除故障,本文将研究空客排故手册TSM和图解目录手册IPC中的排故信息,以及编码译码计算机软件和硬件的情况,判断故障的原因,彻底解决这一故障,提高航空器的可靠性,控制维修成本。最终,在大量研究之后,发现是编码译码计算机在互换性和混装性方面出了问题,并经过系统设备优化升级、手册修改等措施,取得了预期的效果。 相似文献
185.
Zhengtao Ding 《Asian journal of control》2014,16(2):335-344
This paper deals with observer designs for a proposed mathematical model of circadian rhythms which exist in almost every living organism. A 7th order model for mammalian circadian rhythms which captures the main dynamic features is considered in this paper. A recent result of one‐sided Lipschitz observer design in the literature is applied to this mammalian model to show a possibility of reducing measurements for circadian models in system biology. The mammalian model presented may contain an uncertainty parameter. An adaptive design of the Lipschitz observer is then applied to deal with this case. Besides detailed designs of both observers, detailed analysis is also performed for nonlinear functions in the mammalian model to show that the Lipschitz observers can indeed be applied. Several simulation studies of the proposed observers are carried out with the results shown in this paper. 相似文献
186.
Silyl‐crosslinked urethane elastomer modifying epoxy resin has drawn much interest. Here the triethoxysilyl‐terminated polycaprolactone elastomer (PCL‐TESi) modifying diglycidylether of bisphenol A epoxy resins (DGEBA) system was chosen, and then the effect of the type of curing agent on the phase structure of the studied epoxy resin system was investigated. The modified systems were obtained with different phase structures by varying the formulations of the curing agent. It was experimentally shown that with the addition of aminosilane (KBE‐9103), the crosslinked density was greatly increased. The cured system also showed from SEM and TEM analysis that addition of KBE‐9103 increased the compatibility between the PCL‐TESi and DGEBA, which made the ductility of the system decrease, but also indicated from TEM that addition of much KBE‐9103 made the reacted silicone particles coagulate each other. The state of phase separation from TEM in the cured system was theoretically explained. These would serve the deeper studies of the mechanism of silyl‐crosslinked urethane elastomer modifying epoxy resin in the future. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 611–619, 2005 相似文献
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丁宝星 《网络安全技术与应用》2014,(5):143-143
随着现代社会的进步,科学技术取得了飞速发展,计算机网络得到了大量普及,极大地促进了社会生产和人们生活水平的提高,对社会的整体发展起着至关重要的作用.本次研究将从网络维护、管理的意义和应注意的问题出发,对网络网络维护与管理相关策略进行深入分析和探究. 相似文献
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