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991.
Yiping Wang Na Chen Binfeng Yun Yiping Cui 《Photonics Technology Letters, IEEE》2007,19(16):1242-1244
A measurement method has been developed to determine the full-field deformation of a simply supported plane plate under transverse load. The method utilizes strain information provided by a set of four fiber Bragg grating sensors mounted on the plate in a way that all sensors measure strains along one certain direction. The sensors were interrogated using a wavelength swept fiber laser. Utilizing the strain information and the first four terms of Navier solution of simply supported rectangular plate, the necessary parameters for determining the deflection could be computed. By substituting the values of x- and -y- coordinates of each position on the rectangle plate, the full-field deformation information can be obtained. Single-point loading tests were experimentally performed to verify the accuracy of the method. 相似文献
992.
职业建筑师制度是建筑生产方式的产物.建筑服务的内容和标准程序是各国职业建筑师体系的重要内容。通过对比我国与国际上通行的几个职业体系,文章提出我国建筑师职能的全程化、全面化、专业化和建筑制度的透明化、合理化的改革方向.以及建筑制度创新的必要性。 相似文献
993.
浅谈火灾调查的边缘化趋势 总被引:1,自引:0,他引:1
从火灾调查实际工作状态出发,提出火灾调查存在地位边缘化的趋势,并在分析边缘化趋势原因的基础上提出了相应的对策,供火灾调查同仁探讨。 相似文献
994.
A Subcarriers Allocation Scheme for Cognitive Radio Systems Based on Multi-Carrier Modulation 总被引:1,自引:0,他引:1
Tao Luo Tao Jiang Weidong Xiang Hsiao-Hwa Chen 《Wireless Communications, IEEE Transactions on》2008,7(9):3335-3340
Cognitive radio (CR) is a dynamic spectrum access technology as a solution to spectrum under-utilization problem in some licensed bands. Operating over an exceedingly wide spectrum, CR systems usually adopt multi-carrier modulation (MCM) to implement flexible channelization. Consequently, efficient channel allocation scheme becomes extremely important to an MCM based CR (MCM-CR) system. In this paper, a maximum likelihood detection model is developed to detect the presence and locations of licensed users (LUs) signals in the frequency domain. Performance of the detection model, including the optimal detection region, detection probability and false alarm probability, is analyzed. A one-order two-state Markovian chain model is proposed to predict channel status information. In particular, a novel subcarrier allocation scheme for MCM-CR systems is proposed, taking into account the confidence of channel estimation, quality of services (QoS) of rental users (RUs) and throughput. To validate the analytical results, simulations have been conducted to show effectiveness of the proposed scheme. 相似文献
995.
重构在框架开发中的研究与应用 总被引:2,自引:0,他引:2
框架和应用能够通过重构相互促进,应用和框架的并行开发可以加速框架的开发过程.从框架与应用的中间层,框架与应用的接口的结构和形式等方面,对此过程中的重构方法进行了讨论,提出了几种适应于框架与应用并行开发的重构手段. 相似文献
996.
997.
分析了电力行业煤炭采购垄断的弊端。提出要用市场手段和改革的作法解决电煤供需的问题,探索发展多种形式的煤炭资源配置方式,提高能源经济运行的质量。 相似文献
998.
Gregory S. Ho Chen Huang Emily A. Carter 《Current Opinion in Solid State & Materials Science》2007,11(5-6):57-61
Orbital-free density functional theory (OF-DFT) can be made to scale linearly with sample size, allowing thousands of atoms to be treated explicitly with quantum mechanics. State-of-the-art kinetic energy density functionals and ion–electron pseudopotentials are used to obtain accurate structural property predictions for nanoparticles, nanowires, extended surfaces, and nanoindentation of simple metals. 相似文献
999.
活性污泥数学模型入流组分测定及应用 总被引:2,自引:0,他引:2
阐述了活性污泥1号模型人流组分的分析方法,并用这些方法测定了西安市城市污水水质。实验结果表明测定方法操作简单、准确可靠,能为利用模型进行污水处理厂的设计、模拟及管理提供入流组分分析依据, 相似文献
1000.
Optical Splitting Trees for High-Precision Monocular Imaging 总被引:1,自引:0,他引:1
McGuire M. Matusik W. Pfister H. Chen B. Hughes J.F. Nayar S.K. 《Computer Graphics and Applications, IEEE》2007,27(2):32-42
In this article, we consider the design of monocular multiview optical systems that form optical splitting trees, where the optical path topology takes the shape of a tree because of recursive beam splitting. Designing optical splitting trees is challenging when it requires many views with specific spectral properties. We introduce a manual design paradigm for optical splitting trees and a computer-assisted design tool to create efficient splitting-tree cameras. The tool accepts as input a specification for each view and a set of weights describing the user's relative affinity for efficiency, measurement accuracy, and economy. An optimizer then searches for a design that maximizes these weighted priorities. Our tool's output is a splitting-tree design that implements the input specification and an analysis of the efficiency of each root-to-leaf path. Automatically designed trees appear comparable to those designed by hand; we even show some cases where they are superior. With the help of the optimizer, the system demonstrates high dynamic range, focusing, matting, and hybrid imaging implemented on a single, reconfigurable camera containing eight sensors 相似文献