10 resultados para performance testing
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
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。
Resumo:
基于矢量折射定理,研究了透射光束通过双棱镜实现微弧度量级偏转的设计原理,解决了星间激光通信精跟瞄检测的难题。推导了正交双棱镜实现光束偏转的精确公式,提出以水平张角和垂直张角表达光束视场,并说明了单棱镜实现光束偏转的一般情况。根据设计指标和计算结果确定了棱镜的主要参量,进而对光束的偏转结果进行了数值模拟。最后的实验结果与模拟结果基本一致。结果表明:取棱镜棱角α为4°时,棱镜每旋转1’,透射光束变化约1μrad;分别控制双棱镜在其最小偏向角一侧小角度偏转,可以实现光束在水平方向和垂直方向500μ范围内的精确扫
Resumo:
介绍了FM-index压缩查询技术,详细阐述了FM—index的工作流程,描述了实现计算字符串在压缩文本中出现次数的算法。对FM-index的源代码在Linux平台上进行了测试,从测试结果分析了使用FM-index进行压缩查询的优点和不足。最后给出了加快FM-index压缩速度的一个并行化算法的初步设计思路。
Resumo:
性能是Web应用程序成功的要素之一 ,性能测试则是保证这一要素的重要手段 但由于Internet及Web用户的不确定性 ,Web应用程序的性能测试难于传统Client/Server的测试 比较了 3种主要的Web性能测试方法 ;提出了一种简单可行的、通用的方法———模拟驱动的自动负载测试方法 关键的步骤有 :根据系统使用方式和客户端各种特征的分布信息来确定测试负载、设计测试用例 ;利用测试工具开发相应的测试脚本 ;运行测试用例模拟不同类型用户的典型行为 ;收集被测程序的性能数据 结合实例详述了该方法 ,并给出了测试计划的模板
Resumo:
The optical constants of two cyanine dye films that we prepared were measured with a RAP-1-type (RAP is rotating analyzer and polarizer) spectroscopic ellipsometer. Toward making a simplified model for the wafers of a recordable compact disk (CD-R), we give their optimization designs developed with the cyanine dye films. in addition, the dynamic storage performances of two sample disks were tested by our dynamic storage testing system. Measurement results of the sample disks were obtained to test and verify our film designs. (C) 2000 Optical Society of America. OCIS codes: 160.4890, 160.4760, 210.4810.
Resumo:
2-(9-Carbazole)-ethyl-chloroformate (CEOC), a novel pre-column fluorescence derivatization reagent, has been developed for the analysis of aromatic amines. Taking five monocyclic aromatic amines (o-toluidine, aniline, 3,4-dimethylaniline, N-ethyl-p-toluidine, and p-phenylenediamine) as testing compounds, derivatization conditions such as pH of borate buffer, reaction time and fluorescent tagging reagent concentration have been investigated. By a one-step procedure, CEOC reacts readily with the aromatic amines to form stable derivatives with excitation and emission wavelengths, respectively, at 293 and 360 nm. This derivatization reaction could be finished within 20 min even at room temperature. The peak shapes of the derivatized aromatic amines can be improved greatly without any addition of competition amines into the mobile phase. Furthermore, this method can offer excellent quantitative precision with high tolerance of the matrix of samples. (C) 2003 Elsevier B.V. All rights reserved.
Resumo:
2-(9-Carbazole)-ethyl-chloroformate (CEOC), a novel pre-column fluorescence labeling reagent, has been synthesized and applied for the derivatization of phenols. Taken phenol, p-chlorophenol, 2,5-dimethylphenol, 2,4-dichlorophenol and 1,4-dihydroxybenzene as testing standards, the effects of derivatization conditions, such as pH of borate buffer, reaction time and fluorescent tagging reagent concentration, have been systematically studied. Under the optimized conditions, CEOC reacts readily with the phenols to form stable derivatives with excitation and emission wavelengths, respectively, at 293 and 360 nm. The single step derivatization reaction could be finished within 20 min even at room temperature. Such a method has been successfully applied to the analysis of phenols in printing ink by high-performance liquid chromatography. (c) 2005 Elsevier B.V. All rights reserved.