强夯处理红粘土沉降试验研究

红粘土作为高填方体的底层地基,处理其沉降和不均匀性沉降是高填方工程研究的重点。以某机场红粘土高填地基的处理为例,通过沉降分析和方案比选开展强夯处理试验研究。根据场区内不同覆土厚度,采用不同能级进行强夯处理试验确定了合理的施工工艺和参数。通过施工中沉降观测,施工后地基土的物理力学指标试验、载荷试验和工后沉降观测,强夯处理取得了良好的效果,满足设计要求。指导大面积施工时,在质量、造价、工期上都取得了成功。     

嵌入式软件GUI自动化测试平台研究

为实现嵌入式软件的GUI自动化测试,本文对嵌入式软件GUI自动化测试现状深入分析,提出了一种无侵入式的GUI自动化测试框架,利用图像采集与信息识别技术实现测试用例结果判断;利用键盘鼠标模拟技术模拟测试用例执行的人机交互;利用脚本语言嵌入技术实现用例编辑与转换、利用嵌入式软件GUI测试自动化控制技术实现用例的自动驱动与执行。在此基础上,设计并研发了嵌入式软件GUI自动化测试平台,能够方便、有效的实现无侵入式的嵌入式GUI自动化测试。     

基于超声波和云测试的油井液面测试系统研究

针对目前油井液面深度测试系统测量范围小、误差大、稳定性低的缺点,提出了基于声波法测动液面原理,利用时间序列分析技术、新息自适应卡尔曼滤波技术来实时检测回波信号,进而实现对油井液面深度的高精度测量和噪声处理;选用FPGA和云测试技术成功实现了油井液面深度测量系统的远程化和网络化。基于云测试的油井液面远程监测系统目前已在油田生产现场通过测试,测试结果表明,系统稳定,算法实时、高效,动液面深度测量误差小,测量精度高,能满足实际工程应用。     

基于单神经元PID控制器的压电陶瓷控制方法

卫星地面综合测试是卫星研制过程中的重要环节,对系统功能验证及性能评估具有重要作用。传统的卫星地面综合测试系统存在研制周期长、投入较大、自动化流程不够完整、可重用性较差等不足。而北斗导航卫星地面综合测试系统采用分布式、高实时性、可配置、多主机的集成体系结构,是集计算机通讯、实时控制、实时数据处理、事后分析等功能于一体的测试系统,适用于从卫星总装集成到发射各个阶段的电气测试。通过卫星系统级的各项接口、功能、性能指标测试,表明该系统满足支持系统论证、状态确认、问题排查等测试需求,有力支撑了北斗导航卫星的成功发射和在轨运行。     

Large-aperture double-focus laser collimator for PAT performance testing of inter-satellite laser communication terminal

A laser collimator is necessary for testing and verification of the pointing, acquisition and tracking (PAT) performance of inter-satellite laser communication terminals on the ground. The laser collimator must have a large clear aperture to fit the PAT performance testing system. The PAT subsystem has a large field of view for the acquisition and a high angular accuracy for the fine tracking. To resolve the conflict between large field of view and fine angular resolution, a large-aperture double-focus laser collimator is proposed and its optical design and mechanical structure are described. The collimator mainly consists of a primary lens, a reflector, a beam-splitting plate, a secondary lens, two compensating lenses, two imaging sensors and a laser. The primary lens directly forms the long focal length arm of the collimator. The combination of the primary lens and the secondary lens form the short focal length arm of the collimator. The collimator has an angular resolution <0.75 μrad and a 10 mrad field of view. For the collimator, the incident beam is focused on the two imaging sensors by its two arms, and the beam emitted from the laser is collimated and transmitted. The collimator is combined with an optical scanner and a fine beam deflector to test and verify the PAT performance of the inter-satellite laser communication terminal in a full physical manner.     

Comparative analysis on thermal non-destructive testing imagery applying Candid Covariance-Free Incremental Principal Component Thermography (CCIPCT)

Thermal and infrared imagery creates considerable developments in Non-Destructive Testing (NDT) area. Here, a thermography method for NDT specimens inspection is addressed by applying a technique for computation of eigen-decomposition which refers as Candid Covariance-Free Incremental Principal Component Thermography (CCIPCT). The proposed approach uses a shorter computational alternative to estimate covariance matrix and Singular Value Decomposition (SVD) to obtain the result of Principal Component Thermography (PCT) and ultimately segments the defects in the specimens applying color based K-medoids clustering approach. The problem of computational expenses for high-dimensional thermal image acquisition is also investigated. Three types of specimens (CFRP, Plexiglas and Aluminium) have been used for comparative benchmarking. The results conclusively indicate the promising performance and demonstrate a confirmation for the outlined properties.     

星上电缆自动导通绝缘测试仪的设计与开发

星上电缆在航天器系统工程中起到了传递能量和信息的关键作用,并且其上天后具有不可修复性,这就决定了它在电性能检测方面必须做到高质量与高可靠。本文针对传统人工方式进行导通绝缘测试时工作强度大、检测效率低下和可信度低等缺点,设计并开发了一种星上电缆自动导通绝缘测试仪。该仪器基于模块化设计的思想采用中央控制器对各个模块单元进行控制来分别实现测试通道自动切换、测试电压的供给、星上电缆导通绝缘电阻的数据采集、通讯、存储和显示。实践结果表明,星上电缆自动导通绝缘测试仪一方面可以提高电缆导通绝缘测试的可靠性,增强质量控制;另一方面,可以提高效率,节省生产周期,降低劳动强度。     

Testing methods for nanoindentation property of the cuticle of bovine hoof wall and dung beetle’s foreleg femur

Natural biomaterials have extensively been researched since their distinguished properties adapting to their living surroundings. The cuticle surfaces of bovine hoof and dung beetle directly contact soil when they move on soft ground or in soil. Their surface materials and structures can provide some information for designing soil-engaging components of soft terrain-machines. While, it is difficult to measure their mechanical properties since the cuticle of the bovine hoof wall and dung beetle are very thin. Nanoindenter provides a powerful tool for examining the mechanical properties such as reduced modulus and hardness in nano-scale. The testing methods for nanoindentation properties of the cuticle of the bovine hoof wall and dung beetle (Copris ochus Motschulsky) were discussed in this work.     

A Noninvasive, on Wafer Method to Determine the Intrinsic Stress of a Polymer Layer

The method described in this paper allows an investigator to determine the intrinsic stress of a polymer layer in a way that does not result in damage to devices or test structures. The method requires that a small area of the polymer be released from the substrate to form a diaphragm. The diaphragm is stimulated with acoustic white noise and the diaphragm movement is monitored with a laser vibrometer. The first few resonance frequencies of the diaphragm are obtained using a laser vibrometer and then those frequencies are used to calculate the membrane intrinsic bi-axial tension.     

Flexible software reliability growth model with testing effort dependent learning process

A lot of importance has been attached to the testing phase of the Software Development Life Cycle (SDLC). It is during this phase it is checked whether the software product meets user requirements or not. Any discrepancies that are identified are removed. But testing needs to be monitored to increase its effectiveness. Software Reliability Growth Models (SRGMs) that specify mathematical relationships between the failure phenomenon and time have proved useful. SRGMs that include factors that affect failure process are more realistic and useful. Software fault detection and removal during the testing phase of SDLC depend on how testing resources (test cases, manpower and time) are used and also on previously identified faults. With this motivation a Non-Homogeneous Poisson Process (NHPP) based SRGM is proposed in this paper which is flexible enough to describe various software failure/reliability curves. Both testing efforts and time dependent fault detection rate (FDR) are considered for software reliability modeling. The time lag between fault identification and removal has also been depicted. The applicability of our model is shown by validating it on software failure data sets obtained from different real software development projects. The comparisons with established models in terms of goodness of fit, the Akaike Information Criterion (AIC), Mean of Squared Errors (MSE), etc. have been presented.