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81.
Repetitive testing is a fairly common practice in the final testing stage of a chip manufacturing. Decisions on setting initial lot size and the number of testing repetitions are crucial to the effectiveness of the testing process. The task of setting optimal parameters for a testing process is often difficult in practical situations due to uncertainties in both incoming product yield and testing equipment condition during the testing process. In this paper, we investigate a repetitive testing process where the testing equipment may shift randomly from an in-control state to an inferior state during the testing process which, correspondingly, results in different testing errors. We develop a quantitative model that helps us to find optimal test parameters that maximizes system performance. Based on the model, we performed extensive numerical experiments to test the effects of incoming product defective rate, testing equipment shift rate, especially, type II testing errors on decision and system performance. We find that test equipment condition may significantly affect the optimal decisions on the number of test repetitive and initial testing batch size. Further, we find that, while a small type II testing error may have negligible negative effect of system performance, the effect increases as the error or the incoming product yield increases. The results of this research may potentially provide practitioners with insights and a quantitative tool for designing an efficient repetitive testing process. 相似文献
82.
《Analytical letters》2012,45(1):111-123
ABSTRACT Although diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) is mainly used for powdered solid samples, it was found to be highly effective for the analysis of certain gemstones. Small amounts of oils and resins used to fill cracks and fissures in substandard (included) emeralds and rubies could be detected. Because of their very low levels, these organic adulterants can be difficult to detect by measurement of the infrared transmittance spectrum. Rubies have a significantly larger “window-of-detection” for organic clarifying agents than do emeralds. In some cases the spectral information was sufficient to identify the oil or polymer resin. Emeralds that were treated over 20 years ago are still easily identified. The position of the emerald or ruby in the sample holder can affect the intensity of C-H and O-H stretching frequencies as well as those brands characteristic to the gemstones. 相似文献
83.
《Optimization》2012,61(3-4):287-301
Stochastic linear programming (SLP) models involve multivariate integrals. Although in the discretely distributed case these integrals become sums they typically contain a large amount of terms. The purpose of this paper is twofold:On the one hand we discuss the usage of bounds concerning integrals for constructing SLP algorithms and secondly we point out the role of bounds-based algorithms for solving SLP problems. The conceptual considerations are demonstrated in the last section by computational results. The tests have been carried out by utilizing SLP-IOR, our model management system for SLP 相似文献
84.
To accurately model software failure process with software reliability growth models, incorporating testing effort has shown to be important. In fact, testing effort allocation is also a difficult issue, and it directly affects the software release time when a reliability criteria has to be met. However, with an increasing number of parameters involved in these models, the uncertainty of parameters estimated from the failure data could greatly affect the decision. Hence, it is of importance to study the impact of these model parameters. In this paper, sensitivity of the software release time is investigated through various methods, including one-factor-at-a-time approach, design of experiments and global sensitivity analysis. It is shown that the results from the first two methods may not be accurate enough for the case of complex nonlinear model. Global sensitivity analysis performs better due to the consideration of the global parameter space. The limitations of different approaches are also discussed. Finally, to avoid further excessive adjustment of software release time, interval estimation is recommended for use and it can be obtained based on the results from global sensitivity analysis. 相似文献
85.
针对某机载惯导设备在外场的测试需求,设计了以PC-104为显示、控制和数据处理核心,并扩展程控数字表、多通道矩阵板,构建了原位测试仪的硬件电路。根据系统的功能要求和硬件电路特性,利用LabWindows/CVI虚拟仪器平台编制了人机接口界面和测试程序,控制硬件电路对某惯导设备的静态电阻和在线电压进行测试,并接收、分析、处理惯导原位工作时输出的实时串行数据,完成对惯导设备的静态测试和动态性能监测,实现对某机载惯导设备原位测试过程的自动化和测试结果管理的智能化,提高了测试效率和测试精度。该仪器通过改变或控制测试仪器的类别,可实现对多路信号多种性能指标的测试。应用结果表明,该测试仪具有性能稳定、操作简便、应用领域广、通用性强等特点。 相似文献
86.
87.
While the developments of additive manufacturing (AM) techniques have been remarkable thus far, they are still significantly limited by the range of printable, functional material systems that meet the requirements of a broad range of industries; including the health care, manufacturing, packaging, aerospace, and automotive industries. Furthermore, with the rising demand for sustainable developments, this review broadly gives the reader a good overview of existing AM techniques; with more focus on the extrusion-based technologies (fused deposition modeling and direct ink writing) due to their scalability, cost efficiency and wider range of material processability. It then goes on to identify the innovative materials and recent research activities that may support the sustainable development of extrusion-based techniques for functional and multifunctional (4D printing) part and product fabrication. 相似文献
88.
针对基于VXI总线的某型制导武器通用自动测试系统存在的测试效率难以提升、通用化和小型化程度不够、测试技术标准化和信息化水平不高等问题,提出基于PXI总线的某新型制导武器通用自动测试系统的总体设计技术方案,通过采用新型高速仪器总线、合成仪器、TPS可移植等技术,以及软硬件平台模块化、专测组件通用化等设计思想,实现了系统组件标准配置、测试信息网络传输、程序软件移植使用、资源扩展方便快捷的设计初衷,使系统形成跨平台通用化与互操作能力,是现阶段精确制导武器通用自动测试系统较为理想的系统平台解决方案,经新研系统实际试用证明,该设计方案切实可行,能大幅提升多型制导武器通用测试效率,提高部队测试保障能力。 相似文献
89.
90.
微功率无线通信是高级量测体系(AMI)的主要通信方式之一。各厂家的通信模块性能不一,测试技术尚未形成统一的规范。设计了微功率无线通信的测试系统,由射频性能测试系统和协议一致性分析系统组成。系统采用屏蔽测试箱、多功能电磁波小室、综合测试分析仪、误码分析仪、标准协议信号源等模块组成,屏蔽箱对800MHz频率以下的无线电信号有超过70dB 的抑制,可以提供相对纯净的无线电暗室环境,减少外界无线电波的干扰。测试频率范围为30MHz~1GHz,提供66个测试频点,测试频率误差小于2ppm,误码测试精度小于0.001%,功率测试精度(闭环)为5%(0.2dB)。实现了在实验室情况下对微功率无线网络性能的全面测试和评估,具备很好可操作性、便利性和可复现性。 相似文献