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51.
山东改造工程旧房质量检测   总被引:5,自引:4,他引:1  
马心俐 《山西建筑》2007,33(22):89-90
结合某成品仓库改作商业用房的工程实例,对该建筑进行了详细的检测与分析,并根据结果提出了针对性的加固方案,并对加固效果进行了探讨,为工程改造提供了依据,可供类似工程借鉴。  相似文献   
52.
H9000 V4.0计算机监控系统技术特点概要   总被引:8,自引:3,他引:5  
为了满足三峡右岸电站的应用需要,在H9000 V3.0计算机监控系统的基础上研制开发了H9000 V4.0系统,改进和完善了原系统已有功能,开发了新功能,进一步提高了系统的性能指标和可靠性指标。文中主要介绍H9000 V4.0系统的设计原则,以及数据采集、人机联系、报表定制、Web信息发布、历史数据管理等主要新功能。  相似文献   
53.
复合功能原理方案特征建模及其求解过程研究   总被引:4,自引:1,他引:3  
研制了驱动、传动和分离等典型功能原理方案解的知识库,建立了复合功能产品原理解的特征模型,提出了复合功能原理求解的通用进`生平注解和接口匹配并行的策略,进而提出原理解接口特征的嵌套结构及其匹配进程,开发了一个复合功能产品原理方案求解的计算机支持平台,进行了实例验证。  相似文献   
54.
An optimal control problem with nonsmooth performance criterion described by a system of ordinary differential equations is considered. Necessary first-order optimality conditions are obtained.  相似文献   
55.
In this paper, we present the theory for calculating Raman line shapes as functions of the Fermi energy and finite temperatures in zinc blende, n-type GaAs for donor densities between 1016 cm−3 and 1019 cm−3. Compared to other theories, this theory is unique in two respects: 1) the many-body effects are treated self-consistently and 2) the theory is valid at room temperature for arbitrary values of the ratio R = (Q2/α), where Q is the magnitude of the normalized wave vector and α is the normalized frequency used in the Raman measurements. These calculations solve the charge neutrality equation self-consistently for a two-band model of GaAs at 300 K that includes the effects of high carrier concentrations and dopant densities on the perturbed densities of states used to calculate the Fermi energy as a function of temperature. The results are then applied to obtain the carrier concentrations from Fermi energies in the context of line shapes in Raman spectra due to the coupling between longitudinal optical phonons and plasmons. Raman measurements have been proposed as a non-destructive method for wafer acceptance tests of carrier density in semiconductor epilayers. The interpretation of Raman spectra to determine the majority electron density in n-type semiconductors requires an interdisciplinary effort involving experiments, theory, and computer-based simulations and visualizations of the theoretical calculations.  相似文献   
56.
The paper considers vulnerable multi-state series-parallel systems operating under influence of external impacts. Both the external impacts and internal failures affect system survivability, which is determined as the probability of meeting a given demand. The external impacts are characterized by several destructive factors affecting the system or its parts simultaneously.In order to increase the system's survivability a multilevel protection against the destructive factors can be applied to its subsystems. In such systems, the protected subsystems can be destroyed only if all of the levels of their protection are destroyed.The paper presents an algorithm for evaluating the survivability of series-parallel systems with arbitrary configuration of multilevel protection against multiple destructive factor impacts. The algorithm is based on a composition of Boolean and the Universal Generating Function techniques.Illustrative examples are presented.  相似文献   
57.
大变量逻辑函数最佳覆盖问题研究   总被引:2,自引:0,他引:2  
逻辑函数的最佳覆盖,一直是逻辑综合领域的关键环节。尤其是大变量逻辑函数最佳覆盖,对复杂的逻辑综合更为重要,但也更加困难。本文在对逻辑覆盖算法研究的基础上,提出了适合大变量逻辑函数最佳覆盖的Beister改进算法。经过大量算题的测试表明,改进的列覆盖算法在时间复杂度和选择效果方面均优于Beister算法。  相似文献   
58.
In this paper, the spatial resolutions at different directions of bistatic synthetic aperture radar (BiSAR) have been derived from the ambiguity function. Compared with monostatic signal to noise ratio, BiSAR's resolutions of a fixed point target are varying with slow time since BiSAR system is space-variant. Constraints for the assumption of space-invariant bistatic topology are proposed in the paper. Moreover, under the assumption of invariance, the change of resolutions at different point in the image scene is taken into account, and we have specified two key parameters that affect resolutions directly and analyzed the way how they influence on the resolutions.  相似文献   
59.
Magnesiumandmagnesiumalloyshavebeenin vestigatedashydrogenstoragematerialsforseveralde cadesbecausefarmorehydrogenbyweightcanbestoredinthemthaninmostoftheothercurrentlyknownhydrogenstoragealloys .Moreover ,thehighnaturalabundanceofMg ,itslightmassandenviron mentalcompatibilitypotentiallymakemagnesiumoneofthemostprospectivecandidatesforfuturehydrogenstoragematerials .Unfortunately ,thepracticalappli cationofMganditsalloyshasbeenlimitedonlytocertainstoragedevicebecauseoftheirpoorhydriding dehydr…  相似文献   
60.
This paper presents an application of digital signal processing to data acquired by the radio imaging method (RIM) that was adopted to measure moisture distribution inside the human body. RIM was originally developed for the mining industry; we are applying the method to a biomedical measurement because of its simplicity, economy, and safety. When a two‐dimensional image was constructed from the measured data, the method provided insufficient resolution because the wavelength of the measurement medium, a weak electromagnetic wave in a VHF band, was longer than human tissues. We built and measured a phantom, a model simulating the human body, consisting of two water tanks representing large internal organs. A digital equalizer was applied to the measured values as a weight function, and images were reconstructed that corresponded to the original shape of the two water tanks. As a result, a two‐dimensional image containing two individual peaks corresponding to the original two small water tanks was constructed. The result suggests the method was applicable to biomedical measurement by the assistance of digital signal processing. This technique may be applicable to home‐based medical care and other situations in which safety, simplicity, and economy are important.  相似文献   
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