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941.
Microstructures, Reaction Kinetics and Properties of Reaction Between Magnesium and Silica Glass
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In earlier calculation models,the stiffness centers in frame-shear wall structures have been located by the structural torsion stiffness.However,the results are illogical owing to the difference between the distortion character and the shears distribute mechanism of the frames and shear walls.In this paper,a new formula for calculating story stiffness is introduced,which can consider the stiffness of the frames and shear walls at the same time.The structural stiffness centers,the torsion eccentric distances and torsion effect are calculated,and the stiffness of elements is considered also.It is shown that the concept of the presented stiffness model is clear and the results are reasonable,which can be used to calculate the appreciative torsion effect. 相似文献
942.
According to the investigations of urban barrier free facilities, there have been lots of progresses in constructions of barrier free in cities recently. But there are no systematic barrier free facilities in these cities, which would restrict the function and effect of urban barrier free facilities for the handicapped and the elder. This paper puts forward that there should be a development from the urban barrier free facilities to the urban barrier free environment. There are two parts in the barrier free environment,that is the hardy environment and soft environment. Finally,an in-series connection two-core model of barrier free environment has been designed and discussed. 相似文献
943.
944.
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946.
The datum line and mainly three profile height parameters of surface roughness are briefly introduced and the operation principle and system structure of AFM. IPC - 208B with high-resolution, which was successfully developed by Chongqing University, are described in detail, and the emphasis is laid on its application on the nanometer scale surface roughness. Taking stainless steel for example, its micro-structure was observed, and the surface data were analyzed and transacted by special evaluator and the values of three profile height parameters were obtained. Finally the experimental results are briefly analyzed. 相似文献
947.
Valuation based on the bill of quantifies will change the existing valuation mode of tender and bidding. For the standardized management of tender and bidding for power projects and the inteUigentized information management of power enterprises, it is an inevitable trend of reform to apply the valuation mode based on the bill of quantifies. According to the characteristics of power projects, this paper expounds the working process of the valuation mode based on the bill of quantities and analyzes the goal and function need of the tender and bidding management system. Considering the calculation procedure of the valuation and the quote strategy of quantities bill, the composition of fees for the valuation is settled and the calculation method is designed. To establish the management system of tender and bidding with a valuation based on the bill of quantities is beneficial for the costing reform of power projects and the perfection of the tender and bidding market. Therefore it is of great significance to spread the new management mode of project costing with a valuation based on the bill of quantities. 相似文献
948.
949.
SUN Xiao-lan 《保鲜与加工》2007,(4):97-101
Based on by typical coding schemes such as EZW,SPIHT, EBCOT,3D-IEZW,3D-SPIHT and 3D-ESCOT,a context model(3D-OWNER) of wavelet coefficients is proposed,which makes use of partial order,self-similarity between subbands of wavelet coefficients and the correlation of neighboring wavelet coefficients.Experimental results show that the model can achieve higher PSNR than 3D-ESCOT. 相似文献
950.
为降低建筑能耗影响因素间复杂相关性对模型性能的影响,建立了一种基于KPCA-WLSSVM的建筑能耗预测模型。利用核主元分析(KPCA)对输入变量进行数据压缩,消除变量之间的相关性,简化模型结构;进一步采用加权最小二乘支持向量机(WLSSVM)方法建立建筑能耗预测模型,同时结合一种新型混沌粒子群-模拟退火混合优化(CPSO-SA)算法对模型参数进行优化,以提高模型的预测性能及泛化能力。通过将KPCA-WLSSVM模型方法应用于某办公建筑能耗的预测中,并与WLSSVM、LSSVM及RBFNN模型相比,实验结果表明,KPCA-WLSSVM模型方法能有效提高建筑能耗预测精度。 相似文献