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181.
武器装备远程维修决策支援系统设计与开发 总被引:1,自引:1,他引:0
介绍了在网络技术环境下武器装备远程维修决策支援系统的设计与开发方案,简述了系统中的数据处理流程:数据源层、数据采集、数据仓库层、远程传输层、决策分析层、应用层等,介绍了系统的功能模块以及功能模块的功能、应用对象等。 相似文献
182.
武器装备备件维修任务预测 总被引:2,自引:1,他引:1
在对备件的寿命分布类型进行分析的基础上,建立了服从各种分布的备件维修任务预测模型,并从装备可靠性、装备部署数量、装备的复杂程度及装备工作强度4个方面进行了仿真分析。 相似文献
183.
污水生物处理系统中内源过程的研究进展 总被引:4,自引:0,他引:4
污水生物处理系统的内源过程涉及到一系列微生物学、生态学机制和过程,因而对处理系统的各个方面都有重要影响.然而-目前对内源过程的认识还相当有限.本文首先在总结现有知识的基础上对污水生物处理系统中的内源过程作了定义,并对其区分为细胞和群落两个水平-随后,分别对内源过程中的细胞维持、解偶联、程序化细胞死亡、饥饿状态、高等微生物捕食等过程作了综述,总结了其在污水生物处理领域的研究进展.此外.文章还概述了细胞维持能量和细胞衰减速率的测定方法及其研究进展和存在的问题.本文的目的是通过综述现有的知识,推动对污水生物处理系统中内源过程研究的进一步发展. 相似文献
184.
185.
针对LGH-01型空气质量连续自动监测系统在大庆市空气质量自动监测站的有关维护运行问题,总结出一些有效的工作经验和操作方法供大家参考。 相似文献
186.
随着太湖流域、滇池等地蓝藻水华加剧,地表水生物毒性指标作为判断水质安全的一个重要指标,将越来越受到重视.本文通过笔者的实际工作经验出发,结合镇江某水质自动站的特点,提出一些在设备运行过程中需要注意的要点和相关建议,确保生物毒性在线监测系统更加可靠及稳定的运行,在水质在线监测预警体系中发挥更有效的作用. 相似文献
187.
Layer of protection analysis (LOPA) is a widely used method to support process safety in the chemical industries. In the LOPA, the process is classified into many layers, one of such layers considers the basic process control system (BPCS) which commonly uses PID controllers. This kind of controllers cannot deal with constraints. For this reason, the main purpose of this work is to provide a framework to enhance the control layer in the LOPA, which consists of a model predictive control (MPC) with safety features. These features include: sublayers in the controller system (such as real time optimization, target calculation, and MPC), safety constraints, and guarantee of stability by adopting an Infinite Horizon MPC (IHMPC). Here, we propose an approach for control-inspired view to process safety, replacing the BPCS by an Advanced Process Control System (APCS). Moving forward with these concepts, first, a literature review emphasizes the content, showing two perspectives for the APCS. The APCS is designed for two varieties of controllers, a basic IHMPC and IHMPC with zone control to compare the performance. In this framework, the first sublayer consists of a real time optimization (RTO) structure, that calculates the optimal operating condition for the process controller, which computes the control action. Besides, RTO has an additional constraint called the safety index, based on the protection of process operational. RTO and basic IHMPC communicate directly, while for IHMPC with zone control there is an inner sublayer called Target Calculation, it computes a feasible target to the controller, working as another safety strategy in APCS. After that, we demonstrate both structures applied to a CSTR reactor. From the case study, we compared both controllers, and evaluated the effect that the safety index constraint causes in the setpoints, outputs, and control actions. The use of safety constraint in RTO proved to be a safe strategy for the control layer, as well as IHMPC with zone control presented a safer profile than basic IHMPC. Furthermore, the results show that safety constraint affect the economic goal, decreasing its value. 相似文献
188.
Blowout Preventer (BOP) has maintained its function as a safety barrier and the last line of defence against oil and gas spills since its development in the early 1900s. However, as drilling and exploration activities move further offshore, challenges pertaining to reliable operation of the subsea BOP systems continue to be a source of concern for stakeholders in the industry. In spite of recent advancements in reliability analysis of safety instrumented systems (SISs), the research on reliability assessment of BOP is still lacking in some regards. There are gaps in the literature with respect to the incorporation of preventive maintenance (PM) strategies as well as dynamic operating conditions into BOP reliability analysis. To address these gaps, this paper develops an advanced analysis method using stochastic Petri nets (SPN) to estimate the reliability of subsea BOP systems subject to condition-based maintenance (CBM) with different failure modes. The BOP system is divided into five subsystems which are connected in series with each other and categorised into degrading and binary units. The performance of the BOP system in terms of availability, reliability and mean-time-between failures (MTBF) is obtained and analysed. A sensitivity analysis is also performed to evaluate the effect of fault coverage factor and redundancy design on system performance. The results show that both the fault coverage factor and redundancy have significant impact on the BOP's reliability, availability and MTBF. 相似文献
189.
作为一种高效清洁的能源,燃气已经成为城市能源中的重要一员,燃气管网破坏亦成为城市所面临的重大安全隐患。城市埋地燃气管网的破坏风险,往往受到多种影响因素的共同作用。通过分析常州市埋地燃气管网破坏的影响因素,确定了地面沉降、地裂缝、城市内涝、土壤腐蚀等4个风险评价因子。运用MATLAB中的人工神经网络工具,通过人工神经网络计算,优化了模型网络结构,建立了常州市埋地燃气管网破坏风险预测的人工神经网络模型。分析计算结果,并为常州市埋地燃气管网的安全防护提供了建议。 相似文献
190.
Promoting equity in water access: the limits of fairness of a rural water programme in semi‐arid Mozambique
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Bridging the water infrastructure gap has become a major policy concern. In rural areas of Africa, access to water is as much constrained by territorial coverage as it is by the poor conditions of water points due to the difficulty in mobilizing communities for repairs. This paper examines the equity considerations of a rural water and sanitation programme in a district of Mozambique, and their impacts on the achievement of the programme's objectives. Our analysis underlines the contradictions in the conceptualization of equity in the design, planning and implementation of the programme. Even an explicitly pro‐poor strategy can fall short of delivering equity. Our findings stress the fact that overlooking local perception of equity can have a direct impact on the ability of a community to ensure the maintenance of their water points. They call for a careful definition of equity in the design of water programmes, as well as closer attention to this criterion as a precondition to achieving the long‐term objective of the programme. 相似文献