基于时间延迟的多类型维修与经济生产批量联合优化研究

针对目前未能较好的综合考虑多维修类型与经济生产批量联合优化的问题，首先考虑多类型维修关系，基于时间延迟理论求出故障和缺陷次数的表达式；其次，在此基础上，综合考虑生产费用和维修费用的基础上，构建了多类型维修和经济生产批量联合优化模型，以单位时间内总费用最小为优化目标，获得最优检查间隔期和经济生产批量；最后，通过算例分析验证了模型的有效性，说明了第一类缺陷检查次数的多少对费用和经济生产批量影响不大。     

基于法律政策和检测性质的市县级食药检测机构整合探讨

本研究通过国家认证认可监督管理委员会发布的《2016年度检验检测服务业统计报告》相关数据,基于食品药品法律政策、检测性质、规模效应、检测能力建设等方面,对基层食品药品类检验检测资源整合路径进行论证分析。面对当前事业单位机构改革,本研究提出市县级食品药品类检验检测机构应进行跨行业、跨部门、跨层级优化整合的建议,建立以政府实验室为基础、市场检测为补充的食品药品安全检验检测资源配置模式,为实现基层食品药品安全监管现代化治理提供良好的检验检测技术服务支撑能力。     

Application and validation of a statistically derived risk-based sampling plan to improve efficiency of inspection and enforcement

The statistically derived risk-based sampling plan for surveillance sample assignments of chemical and biological hazards was designed using binomial probability distribution. The binomial statistics was applied to the past 3-year data to estimate a confidence interval and a sample size aiming to improve efficiency and effectiveness of the agency's sampling and inspectional activities. The accuracy of the statistical models and computed estimates were validated in the following years. The ranges of confidence interval and sample size appeared to be significantly influenced by a level of the violation rate of feed product samples, an acceptable error, a number of the analyzed samples, and a statistical significance level. The violation rates of feed products for target analytes (aflatoxins, fumonisins, Salmonella, and dioxin) in the validation data were lower than those of the average 3-year data in most feed products. Besides, the actual violation rates of the validation samples did not exactly fall within the anticipated range of the confidence interval estimates. Such a discrepancy is considered introduced by several factors such as sample size adequacy, skewed distribution of a target analyte in feed products, and unique analyte/product combination. The overall study results indicate that the risk-based plan of work would provide a more effective and efficient risk management tool to help improve the oversight of the feed industry and the compliance to feed safety standards.     

Integrated Inspection of QoM,QoP, and QoS for AOI Industries in Metaverses

With the rapid development of information technologies such as digital twin, extended reality, and blockchain, the hype around "metaverse" is increasing at astronomical speed. However, much attention has been paid to its entertainment and social functions. Considering the openness and interoperability of metaverses, the market of quality inspection promises explosive growth. In this paper, taking advantage of metaverses, we first propose the concept of Automated Quality Inspection (AutoQI), which performs integrated inspection covering the entire manufacturing process, including Quality of Materials, Quality of Manufacturing (QoM), Quality of Products, Quality of Processes (QoP), Quality of Systems, and Quality of Services (QoS). Based on the scenarios engineering theory, we discuss how to perform interactions between metaverses and the physical world for virtual design instruction and physical validation feedback. Then we introduce a bottom-up inspection device development workflow with productivity tools offered by metaverses, making development more effective and efficient than ever. As the core of quality inspection, we propose Quality Transformers to complete detection task, while federated learning is integrated to regulate data sharing. In summary, we point out the development directions of quality inspection under metaverse tide.      

Optimal load rating-based inspection planning of corroded steel girders using Markov decision process

Steel girder bridges are vulnerable to corrosion. To maintain their safety above a predefined target level, the load rating can be computed from the inspection results and guide the following maintenance actions. Optimizing inspection and maintenance based on load ratings has substantial practical and economic relevance. Load rating-based strategies can be categorized based on whether the inspection interval and replacement criteria are fixed or flexible. Existing studies focus on fixed inspection intervals throughout the service life. In general, their results are not optimal for inspection planning. To reduce life-cycle cost, aged steel girders may be inspected and repaired in an adaptive manner. To this end, a method based on Markov decision process (MDP) is proposed to compare the life-cycle cost of four load rating-based policies (i.e. uniform or adaptive non-uniform inspection interval, and fixed or adaptive replacement threshold). Load rating-based inspection planning is formulated as MDP and the optimal plans are obtained using dynamic programming. The conventional approach to discretize states cannot accurately approximate the non-stationary deterioration process, while state augmentation is successful in doing this but will increase computational cost. A comparison of two approaches is made to investigate their effects on life-cycle cost. A bridge girder under corrosion attack is used as an illustrative example. The results show that the load rating-based plan with an adaptive non-uniform inspection interval and fixed replacement threshold obtained using the state augmentation technique can be near-optimal.     

电力绝缘性能检测

通过绝缘介质的理论分析,阐述了电气设备绝缘检查通常的摇表检查,直流耐压及漏泄电流的测量,交流工频耐压,介质损失角的测量,在线检测等方法,以用来指导电气工程施工的安装和调试.     

Reliability analysis with nondestructive inspection

Nondestructive inspection tools are commonly used to inspect structures or structural components with resistance deterioration due to defect size growth. The quality of the tools is mainly defined by the rate of detecting a defect with defect size s, (s), and the accuracy in sizing a detected defect. The uncertainty of sizing a detected defect can be incorporated in limit state functions that include defect size, and a reliability evaluation can be carried out with the efficient first-order reliability method (FORM). The rate of detecting a defect can also be incorporated in the reliability evaluation of an inspected structure or structural component. This is done, in this paper, by introducing a standard normally distributed variate, Z, and defining a limit state function as a function of and (s). Advantages of using this limit state function, rather than using a limit state function based on the actual defect size and the critical defect size distributed according to the rate of detection curve, are discussed. It is shown that one only needs to use the mean rate of defect detection curve to consider the uncertainty in the rate of detection. The incorporation of the uncertainty in rate of detection for reliability updating analysis with inspection results, and for reliability-based selection of optimal inspection and maintenance schedule for resistance deteriorating structures are also presented. The proposed approach is illustrated by two examples in evaluating reliability with inspection information and in selecting an optimal inspection and maintenance schedule by minimizing the probability of time to failure before inspection and before the time at the end of remaining service life.     

南京市茶南基坑监测及成果分析

通过时南京市茶南基坑支护结构的深层水平位移、沉降、基坑水平位移、支撑轴力监测，得出了基坑周边水平位移及深层土体的水平位移随时间的变化曲线；周边建筑物的沉降随基坑开挖的变化关系；支撑轴力随时问的变化曲线。并时这些变化曲线进行了研究分析。     

谈回弹法检测混凝土抗压强度

本文就回弹法测强的意义、测试中技术要求、影响测强的因素等有关问题提出自己的看法和认识     

既有建筑玻璃幕墙玻璃的检测鉴定方法

玻璃为既有建筑幕墙的重点检查项,笔者根据工作经验和相关规范对玻璃的现场检测鉴定流程和要点进行了归纳和总结,有利于此类工作开展。