燃气输配管网可靠性的故障树分析

对引起管网失效的各个因素进行系统分析，建立了燃气输配管网失效故障树，对该故障树进行了定性和定量分析。     

埋地燃气管道的风险评估技术

阐述了我国进行燃气管道风险评估面临的挑战。用改进的故障树法建立埋地燃气管道阴极保护的风险评估模型，将风险评估模型的结果与现场实测、开挖结果相比较，二者基本一致。该风险评估模型为管道的安全运行及防腐系统的修复工作提供了科学依据。     

集中空调系统的可靠性分析

运用系统可靠性理论,结合集中空调系统的功能特点,建立了可靠性数学模型。在空调系统各组成单元故障模式分析的基础上,分别建立了集中空调系统和制冷系统的故障树。采用最小割集分析法确定了导致制冷系统失效的主要因素,提出了改善集中空调系统可靠性的途径。     

旧有建筑安全隐患及故障树分析方法

旧有建筑在许多方面存在安全隐患,运用定性和定量的方法分析旧有建筑安全隐患是城市防灾的重要课题之一。故障树分析方法在许多工业领域的成功运用,为它用于旧有建筑安全事故隐患分析提供了可能性。运用该方法分析了旧有建筑火灾隐患,并对旧有建筑安全评价的发展方向做出预测。     

精细化尺度下的城市绿地建设公众 参与途径——以柏林、伦敦“植树计划” 为例

绿地空间具有减缓城市热岛效应、调节微气候、减轻噪声、改善城市居民身心健康、增加生物多样性等诸多优点。城市绿地建设是城市可持续发展的基础,不能仅依靠“自上而下”的上层规划来进行,同时应关注社会公平性、经济效益、市民意愿等因素,从精细化尺度贯彻公众参与制度,真正实现市民共建的“人民城市”。对公众参与政策的起源与发展情况进行简要介绍,并探讨在城市绿地建设中不同阶段的公众参与方式。以柏林、伦敦的“植树计划”政策为例,从资金来源、公众参与方式、参与形式、参与层次、计划成效几方面,比较分析2个城市植树计划的公众参与模式与深度及优点与不足,以对中国绿地建设提供借鉴。最后,针对我国公众参与绿地建设存在的问题,提出精细化构建制度法规保障体系、精细化资金来源途径,以及搭建精细化参与渠道三方面的启示与建议。     

Remediation of groundwater contaminated with MTBE and benzene: the potential of vertical-flow soil filter systems

Field investigations on the treatment of MTBE and benzene from contaminated groundwater in pilot or full-scale constructed wetlands are lacking hugely. The aim of this study was to develop a biological treatment technology that can be operated in an economic, reliable and robust mode over a long period of time. Two pilot-scale vertical-flow soil filter eco-technologies, a roughing filter (RF) and a polishing filter (PF) with plants (willows), were operated independently in a single-stage configuration and coupled together in a multi-stage (RF + PF) configuration to investigate the MTBE and benzene removal performances. Both filters were loaded with groundwater from a refinery site contaminated with MTBE and benzene as the main contaminants, with a mean concentration of 2970 ± 816 and 13,966 ± 1998 μg L⁻¹, respectively. Four different hydraulic loading rates (HLRs) with a stepwise increment of 60, 120, 240 and 480 L m⁻² d⁻¹ were applied over a period of 388 days in the single-stage operation. At the highest HLR of 480 L m⁻² d⁻¹, the mean concentrations of MTBE and benzene were found to be 550 ± 133 and 65 ± 123 μg L⁻¹ in the effluent of the RF. In the effluent of the PF system, respective mean MTBE and benzene concentrations of 49 ± 77 and 0.5 ± 0.2 μg L⁻¹ were obtained, which were well below the relevant MTBE and benzene limit values of 200 and 1 μg L⁻¹ for drinking water quality. But a dynamic fluctuation in the effluent MTBE concentration showed a lack of stability in regards to the increase in the measured values by nearly 10%, which were higher than the limit value. Therefore, both (RF + PF) filters were combined in a multi-stage configuration and the combined system proved to be more stable and effective with a highly efficient reduction of the MTBE and benzene concentrations in the effluent. Nearly 70% of MTBE and 98% of benzene were eliminated from the influent groundwater by the first vertical filter (RF) and the remaining amount was almost completely diminished (∼100% reduction) after passing through the second filter (PF), with a mean MTBE and benzene concentration of 5 ± 10 and 0.6 ± 0.2 μg L⁻¹ in the final effluent. The emission rate of volatile organic compounds mass into the air from the systems was less than 1% of the inflow mass loading rate. The results obtained in this study not only demonstrate the feasibility of vertical-flow soil filter systems for treating groundwater contaminated with MTBE and benzene, but can also be considered a major step forward towards their application under full-scale conditions for commercial purposes in the oil and gas industries.     

仓储某型云爆弹失效分析与实验研究

云爆弹是新一代轻型系列武器中的面毁伤武器,采用失效树分析方法,确定了仓储某型云爆弹的失效模式,研究了主要失效因素,并通过试验验证了硝酸异丙酯对推进剂的安定性能和燃烧性能以及对电火工品的影响。发现硝酸异丙酯渗漏后会降低推进剂的储存安定性,影响推进剂的燃烧规律并会溶解溶胀电火工品,导致其失封。     

火箭漏电故障诊断技术研究

基于集对分析理论和故障树的相关知识,研究了火箭(LV)测试及发射过程中的一类新的漏电故障诊断技术。在火箭漏电故障原因的各种可能组合方式构造火箭漏电故障树的基础上,引入中间状态概率的概念。基于集对分析联系数理论确立了漏电故障因素的重要度模型,对系统底事件和顶事件的失效概率进行分析,从而确立了火箭漏电故障诊断的新方法。该方法成功应用于火箭控制系统漏电故障诊断的工程实例表明:该方法能及时诊断火箭系统的漏电故障原因,采取合理的措施有效地排除故障,具有良好的更新能力和应用前景。     

某型自行火炮综合电气系统故障诊断专家系统

针对某自行火炮综合电气系统维修保障现状,在分析电气系统结构、原理和特点的基础上,综合故障现象,提出采用故障树分析方法开发故障诊断专家系统。介绍故障诊断专家系统组成结构,通过研究电气系统结构和故障机理掌握原理性的知识,以及从专家处获取启发式的经验诊断知识构建知识库,并采用正向推理机制,开发综合电气系统故障诊断专家系统。结果表明,该方法能提高电气系统的维修保障水平,辅助维修人员快速完成复杂维修事务。     

轻型鱼雷实航中航程和航速异常现象分析及解决措施

为了解决航程不足和航速阶跃式跳变问题,对轻型鱼雷在实航中出现的航速和航程异常现象进行了分析并绘制了故障树。综合动力、自导、供电等系统,从全雷供电切换、能量守恒和噪声分析以及全雷转矩平衡等方面入手,对现象的成因和过程进行了深入分析,并得出了航程偏短主要是由于配气阀座、体之间的燃气泄漏造成的以及电源切换是航速阶跃式跳变的原因结论,这些故障通过采取相应的措施能够得到解决。