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1.
A novel image sequence-based risk behavior detection method to achieve high-precision risk behavior detection for power maintenance personnel is proposed in this paper. In this method, the original image sequence data is first separated from the foreground and background. Then, the free anchor frame detection method is used in the foreground image to detect the personnel and correct their direction. Finally, human posture nodes are extracted from each frame of the image sequence, which are then used to identify the abnormal behavior of the human. Simulation experiment results demonstrate that the proposed algorithm has significant advantages in terms of the accuracy of human posture node detection and risk behavior identification.  相似文献   
2.
针对一种煤矿用本安型缺水传感器在现场安装及维护难度大,以及抽采泵供水状态下管道内有水但传感器检测显示为无水,或抽采泵停止工作时传感器检测显示有水问题,分析原产品中磁体及探头感应装置结构。改进其结构形式,并优化安装,使检测稳定可靠。实现抽采泵管道用缺水传感器的可靠性设计和轻量化设计。  相似文献   
3.
随着现代化进程的加快,电气设备接地装置的应用越来越广泛,从安全的角度考虑,其运行和维护受到了全社会的广泛关注,如何介绍应用当中存在的安全隐患成为当前关注的主要内容。本文系统概括的分析了电气设备接地装置的运行和维护情况,为其安全应用提供一定的参考。  相似文献   
4.
国家电网公司信息化程度越来越高,单机运维审计系统产生的数据量日益增多,对海量数据高效率存储分析性能严重下降,系统稳定性降低。为满足国家电网当前对运维审计系统数据存储分析以及系统稳定性的需求,在Hadoop开源架构的基础上,本文提出基于Hadoop集群的海量数据分布式存储方法和基于Heartbeat的心跳检测技术,实现基于Hadoop的电力运维审计系统。〖JP2〗实验测试结果表明,基于Hadoop的电力运维审计系统相比单机系统可用性提高了8.42%,大大提升了存储分析海量数据的性能,具有系统工作稳定和服务不间断等优势。  相似文献   
5.
文章针对乌鲁木齐机场多普勒天气雷达(以下简称ADWR)2009~2019年发生的故障次数、故障分布以及备件更换情况,逐年统计故障率,深入分析了ADWR系统性能,总结出运行维护中的经验,就如何更好地提高雷达业务运行指标提出建议,以提高ADWR雷达的维护、维修能力,建立有针对性的备件管理,为科学的业务运行管理提供依据。  相似文献   
6.
新冠肺炎确诊患者粪便病毒检测呈阳性,意味着新冠病毒可能会通过气溶胶的方式进行传播,使得生活排水系统的卫生安全问题时隔17年后再次摆在人们面前。以保障人的健康为出发点,从基础研究、排水机理、系统设计、施工监管、维护管理等多方面提出了提升生活排水系统卫生安全性能的关键问题,以期从全生命周期内切断排水系统可能传播病毒的隐形途径,切实保障居民居家健康。  相似文献   
7.
Despite a substantial literature suggests that computer-mediated communication impact individuals’ various psychosocial factors, relatively few studies have elucidated the underlying mechanism behind these associations. Building upon self-disclosure theory and previous studies, the principal purpose of this present research is to systematically explore the relationships among microblog utilization, online self-disclosure, friendship maintenance, and perceived life satisfaction. A web-based survey was implemented using a total of 426 university students in Northwestern China. Structural equation modeling reveals that intensity of microblog use is positively associated with these students’ friendship maintenance and life satisfaction. Additionally, online self-disclosure plays the crucial mediatory role in the relationships between microblog use, quality of relationships, and gratification with life. The results imply that as microbloggers disclosure their inner thoughts or emotional states with other users online, they could foster their friendship maintenance and obtain greater life satisfaction. However, contrary to the expectation, students’ friendship maintenance is not discovered to be a significant predictor of the sense of life satisfaction in the online environment. Overall, these obtained outcomes of the empirical work could offer new insights into the deep comprehending of the social psychological process of microblogging among younger generation in the new media context.  相似文献   
8.
任伟 《山东煤炭科技》2020,(1):24-25,28,30
为了提高综采工作面端头超前应力区顶板稳定性,降低顶板支护费用,对8309工作面端头应力区提出了耦合让均压支护技术,控制了端头应力区顶板下沉、破碎现象,可降低支护成本费用320元/m。  相似文献   
9.
ABSTRACT

In this paper, we consider the problem of constraint management in Linear Periodic (LP) systems using Reference Governors (RG). First, we introduce the periodic-invariant maximal output admissible sets for LP systems. We extend the earlier results in the literature to Lyapunov stable LP systems with output constraints, which arise in RG applications. We show that, while the invariant sets for these systems may not be finitely determined, a finitely-determined inner approximation, which is periodically invariant, can be obtained by constraint tightening. We then analyze the geometric and algebraic relationship between these sets and show that these sets are related via simple transformations, implying that it suffices to compute only one of them for real-time applications. This greatly reduces the memory burden of RG (or other similar constraint management strategies), at the expense of an increase in processing requirements. We present a thorough analysis of this trade-off. In the second part of this paper, we present two RG formulations, and discuss their properties and algorithms for their computation. Numerical simulations demonstrate the efficacy of the approach.  相似文献   
10.
This paper deals with degradation processes whose onset is triggered at a random time and which stay hidden until they are discovered through inspection or when they begin to show symptoms. This is applicable in many healthcare and industrial scenarios, for example, in the modeling of breast cancer or termite infestation. In our model, we assume that symptoms appear after hitting a random critical threshold and that inspections may have a sensitivity less than one as well as a nonzero false positive rate. The expected cost of repair is derived, and the inspection rate is optimized for a cycle (which lasts from degradation-free to repaired state). This gives results for three cases: the first is for a finite observation period with no degradation recurrence, the second for infinite time horizon allowing recurrence. In the third case, we derive an upper bound for the expected cost in a given constant time period. Finally, the model is applied to determine the optimal strategy for breast cancer screening with regard to the effects of different parametrizations.  相似文献   
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