136 resultados para TSP module


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提出贪心遗传算法。通过构建“基因库”形成好的“基因片断”,从而生成高性能的初始种群;依据贪心选择的原则指导遗传操作,实施贪心交叉操作和贪心变异操作;移民操作向种群引进新的遗传物质,克服了封闭竞争缺点,并且可以避免早熟收敛。贪心遗传算法可以大大加快搜索的速度,仿真结果表明算法是十分有效和实用的。

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气溶胶对气候和人类的健康都有重要影响。因此,研究大气总悬浮颗粒物(TSP)的化学组成和物理特性对更深入地了解气溶胶对气候和人类健康的影响具有重要意义。贵阳是中国受燃煤污染比较严重的城市之一,大气中高含量的SO2是其最明显的特征。尽管最近几年空气质量有所改善,但是该区的大气污染问题还比较严重,空气质量仍然不容乐观。我们于2005年1月1日到2005年12月31日在中科院地球化学研究所内全年采集总悬浮颗粒物(TSP)样品,分析测试了其主要无机离子(F-、Cl-、SO42-、NO3-、NH4+、K+、Na+、Ca2+和Mg2+)的化学性质,并结合当地的气象参数(温度,风速,降雨量和相对湿度)系统地研究了TSP及其水溶性无机离子的季节变化特征。本论文的主要结论有: 1. TSP的浓度变化范围为36.91~313.44µg/m3,年均值106.60µg/m3;各离子摩尔浓度的大小顺序为:SO42-> NH4+> Ca2+ > NO3-> K+ > Na+ > Cl- > Mg2+ > F-;SO42- (23.04±12.16µg/m3)和NH4+(3.05±2.23µg/m3)是最主要的离子,分别占总离子摩尔数的37%和30%。TSP及其组分都有明显的季节变化,TSP、Cl-、SO42-、NO3-、NH4+、K+、Na+、Ca2+和Mg2+浓度的冬/夏比值分别为:1.29、5.23、1.35、2.37、1.73、1.22、1.84、1.23和1.02。 2. 温度对TSP及其水溶性无机组分的影响呈现一定的季节变化模式,冬天随温度的升高TSP及其水溶无机组分的浓度也升高,夏天随温度的升高TSP及其水溶性无机组分的浓度降低。但是从全年来看,温度与TSP及其水溶性无机组分之间有弱的负相关性,即随温度的升高,TSP及其水溶性无机组分的浓度有不同程度的下降。相对湿度与TSP及其水溶性无机组分之间存在明显的负相关关系,即随大气相对湿度的增加,TSP及其水溶性无机组分的浓度下降。在相对湿度与TSP及其水溶性无机组分浓度的日变化图中表现为相对湿度的波谷与TSP及其水溶无机组分的浓度的波峰相对应。风速与TSP及其水溶无机组分的浓度之间呈现弱的负相关性。在贵阳,风速对TSP及其水溶无机组分的影响主要表现为扩散作用和稀释作用,由风速导致的尘土再悬浮作用并不明显。雨量对TSP及其水溶性无机组分的影响主要是湿清除作用,具体表现为无雨天TSP及其水溶性无机组分的浓度较雨天高。影响TSP、Ca2+、Mg2+和F-的主要气象参数是相对湿度(RH)和风速,影响SO42-、NO3-、NH4+和Cl-的主要气象参数是温度。 3. 贵阳大气总悬浮颗粒物(TSP)总体偏酸性,TSP水溶液pH值的年均值为6.27±0.41,与总阴离子与总阳离子的当量比Q的年平均值为0.82一致;TSP中高含量的SO42-是贵阳的TSP显酸性的主要原因。 4. NH4+与SO42-和NO3-的相关系数(R)分别为0.85和0.65,NH4+与SO42-的摩尔比值为0.8,说明贵阳TSP中的NH4+主要以(NH4)2SO4的形式存在。Ca2+和Mg2+有较好的相关性(R=0.72)和相似的变化特征,说明二者可能有共同的来源。 5. 2005年贵阳TSP中SO42-/ Ca2+的平均值为13.64,几乎是干净大陆SO42-/ Ca2+的本底值的20倍,说明贵阳的大气污染主要是人为因素所致。NO3-/SO42-的平均值为0.15,说明固定源对贵阳气溶胶的贡献比移动源(通常指交通工具所排放的尾气)对气溶胶的贡献大;

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A time averaged two-dimensional fluid model including an electromagnetic module with self-consistent power deposition was developed to simulate the transport of a low pressure radio frequency inductively coupled plasma source. Comparsions with experiment and previous simulation results show, that the fluid model is feasible in a certain range of gas pressure. In addition, the effects of gas pressure and power input have been discussed.

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本文利用挤铸造方法结合热压的方法制备了Al_(18)B_4O_(33)w/Al和SiCw/Al复合材料,实现了对增强体取向的调整。利用SEM在位观测、MTS宏观拉伸等实验方法研究了复合材料的细观结构、细观损伤演化规律和材料的宏观性能。通过理论分析、数值计算,结合实验的方法,定量地讨论了材料性能和其微观结构参数之间的关系,定性地总结了短纤维增强金属基复合材料的细观损伤演化规律。经过分析和实验,阐明了热挤压对短纤维增强金属基复合材料增强体空间取向性(取向密度)的影响;讨论了在短纤维增强金属基复合材料中宏观应变和基体、增强体应变的关系;并且进一步研究了密排、多取向群体短纤维增强体的应变,在材料处于弹性和塑性阶段的演化规律;提出了利用增强体轴向应变和材料宏观应变在该方向的分量之比值λ_f来描述增强体增强效果,给出了λ_f在材料承载过程中的演化规律;总结了短纤维增强金属基复合材料的性能(弹性模量)和晶须空间取向之间的关系;利用修正了的混合定律比较好地预测了短纤维增强金属基复合材料的弹性模量;并且进一步预测了短纤维增强金属基复合材料的弹塑性性能。

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According to the experimental results and the characteristics of the pressure-sensitive fractured formation, a transient flow model is developed for the deep naturally-fractured reservoirs with different outer boundary conditions. The finite element equations for the model are derived. After generating the unstructured grids in the solution regions, the finite element method is used to calculate the pressure type curves for the pressure-sensitive fractured reservoir with different outer boundaries, such as the infinite boundary, circle boundary and combined linear boundaries, and the characteristics of the type curves are comparatively analyzed. The effects on the pressure curves caused by pressure sensitivity module and the effective radius combined parameter are determined, and the method for calculating the pressure-sensitive reservoir parameters is introduced. By analyzing the real field case in the high temperature and pressure reservoir, the perfect results show that the transient flow model for the pressure-sensitive fractured reservoir in this paper is correct.

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A new approach based on the gated integration technique is proposed for the accurate measurement of the autocorrelation function of speckle intensities scattered from a random phase screen. The Boxcar used for this technique in the acquisition of the speckle intensity data integrates the photoelectric signal during its sampling gate open, and it repeats the sampling by a preset number, in. The average analog of the in samplings output by the Boxcar enhances the signal-to-noise ratio by root m, because the repeated sampling and the average make the useful speckle signals stable, while the randomly varied photoelectric noise is suppressed by 1/ root m. In the experiment, we use an analog-to-digital converter module to synchronize all the actions such as the stepped movement of the phase screen, the repeated sampling, the readout of the averaged output of the Boxcar, etc. The experimental results show that speckle signals are better recovered from contaminated signals, and the autocorrelation function with the secondary maximum is obtained, indicating that the accuracy of the measurement of the autocorrelation function is greatly improved by the gated integration technique. (C) 2006 Elsevier Ltd. All rights reserved.

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根据固体激光器抽运的技术要求,设计了一种具有水冷装置的大功率半导体激光器二维阵列模块,并对半导体激光器热沉和致冷系统的热流进行了分析。在不同占空比下,对该模块进行了测试与分析。该模块的中心波长为810nm,光谱半峰全宽(FWHM)为2.5nm,工作电流为110A(200μs,10%占空比),循环水温为15℃时输出峰值功率为280W。结果表明,该封装结构在占空比小于5%时器件工作特性良好,在10%占空比F也可正常工作。利用该模块可以组合成多种几何结构、功率更高的半导体激光器组件。

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Based on birefringence, a building-block stacking technique is suggested in this paper. A solid-state optical morphological processor module is thus developed, which is an integration of a beam array generator submodule, an optical connector submodule, and a Pockels readout optical modulator. It is shown that the technique is compact in construction, simple for fabrication, and insensitive to the environment.

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We present, for the first time to our knowledge, a generalized lookahead logic algorithm for number conversion from signed-digit to complement representation. By properly encoding the signed-digits, all the operations are performed by binary logic, and unified logical expressions can be obtained for conversion from modified-signed-digit (MSD) to 2's complement, trinary signed-digit (TSD) to 3's complement, and quarternary signed-digit (QSD) to 4's complement. For optical implementation, a parallel logical array module using an electron-trapping device is employed and experimental results are shown. This optical module is suitable for implementing complex logic functions in the form of the sum of the product. The algorithm and architecture are compatible with a general-purpose optoelectronic computing system. (C) 2001 Society of Photo-Optical Instrumentation Engineers.

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We propose a novel structure of planar optical configuration for implementation of the space-to-time conversion for femtosecond pulse shaping. The previous apparatuses of femtosecond pulse shaping are 4f Fourier-transforming type system that is usually large, expensive, difficult to align. The planar integration of free-space optical systems on solid substrates is an optical module with the attractive advantages of compact, reliable and robust. This apparatus is analyzed in details and the design of the particular lens for femtosecond pulse shaping based on planar optics is presented. (c) 2006 Elsevier GmbH. All rights reserved.

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提出一种精确检测光刻机激光干涉仪测量系统非正交性的新方法。将对准标记曝光到硅片表面并进行显影;利用光学对准系统测量曝光到硅片上的对准标记理论曝光位置与实际读取位置的偏差;由推导的位置偏差与非正交因子、坐标轴尺度比例、过程引入误差的线性模型,根据最小二乘原理计算出干涉仪测量系统的非正交性。实验结果表明,利用该方法使用同一硅片在不同旋转角下进行测量,干涉仪测量系统非正交因子的测量重复精度优于0.01 μrad,坐标轴尺度比例的测量重复精度优于0.7×10-6。使用不同的硅片进行测量,非正交因子的测量再现性优于

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从靶场反射镜架模块的机械结构设计布局所需几何空间的角度出发,根据大口径、列阵器件的特殊要求,给出符合“神光Ⅲ”装置总体技术要求的ICF靶场光束口径与列阵间隔之间的关系,得出靶场△纵、△横应满足的公式.