基于事故树分析的水泵断轴事故的危险评价

基于事故致因理论建立水泵断轴事故模型,将水泵断轴事故危险源分为工作应力超负荷、工作强度超负荷、泵轴维护正确三类,提出基于事故树分析法的水泵断轴危险性专项评价方法。通过对最小割集和最小径集的分析可知,对水泵断轴影响最大的是作用时间过长、次数过多、承受应力过大、对中不符合要求、装配过紧或过松、形位公差过大。对水泵断轴事故的预防提出建议,对水泵运行时间进行合理分配,正确合理地装配水泵并且时刻关注水泵的运行状态。     

基于模糊事故树的溃坝风险评估与管理

将模糊理论引入到溃坝事故树的编制中,首先介绍了事故树分析法,分析了模糊集理论、基本事件模糊数的三角归一化方法及其模糊重要度;然后给出了基于模糊事故树的溃坝风险评估与管理步骤和流程图;最后以某土石坝溃坝为例,对各基本事件进行了模糊重要度求解,找出了对溃坝影响较大的基本事件,确定了降低溃坝发生概率的方法。     

模糊数学法在水环境质量评价中的应用——以滦河迁安段为例

在自然科学或社会科学研究中，存在着许多定义不很严格或者说具有模糊性的概念。这里所谓的模糊性，主要是指客观事物的差异在中间过渡中的不分明性。这些通常是本来就属于模糊的概念，为处理这些模糊概念而进行的种种努力，催生了模糊数学。通过对环境质量指标的综合分析，确定了模糊综合评价方法，并将其应用到滦河迁安段水环境质量评价中。结果表明，该方法较传统的方法能提供更多的信息，从而提高了评价结果的科学性。     

南水北调东线工程输水系统运行风险研究

南水北调东线工程输水系统涉及堤防漫堤、渗透和失稳三种失事模式。分析了输水系统的风险机制,识别出系统的风险来自外来荷载、内部结构、运行管理等三方面,参考我国大坝安全评价和堤防工程设计规范等,建立了风险评价基准。采用层次-模糊分析法计算了输水河道运行综合风险概率;以河段长度为参数,通过聚类分析,得出了输水河道失事后果等级。在此基础上,根据风险评价基准,算出了各输水河道的风险等级。结果表明:高水河风险为低,中运河、胶东输水干线风险为中等,里运河等8段输水河道风险为较低。     

Performance Assessment of a Water Delivery Canal to Improve Agricultural Water Distribution

The performance of an irrigation water delivery canal located in northern Iran, which supplies water to 5,514 ha of paddy fields through ten secondary canals, was investigated. Throughout the rice growing season in the region, two performance measures, the measure of adequacy (P_A) and the measure of equity (P_E), were calculated for the system. It was observed that the canal, in its current physical and operational condition, is unable to distribute available water among all upstream and downstream users adequately. While 46.7?% of the total area is experiencing significant water scarcity, the amount of water received by 51.4?% of the area is approximately three times more than required. To improve the performance of the canal, structural and non-structural modifications were proposed and assessed using the SOBEK hydrodynamic model. The results showed that implementing the proposed modifications would decrease the measure of equity by 71.7?%, meaning that the overall performance of the canal could be reasonably improved.

     

大伙房输水工程TBM3施工段施工风险评估

大伙房水库输水工程TBM3施工段查梁子段,地质条件较为复杂,TBM能否顺利通过存在较大的风险,为此对工程提前进行了风险评估和施工预案准备。结果表明,在对围岩软弱破碎带、断层及含水地带采取相应的处理措施后,采用TBM施工比钻爆法更能适应不良地质条件下不同围岩的掘进要求。     

低压管道输水工程附属设施的质量评定

农田低压输水管道工程的附属设施是保证管道系统安全、正常运行的重要设施,但长期缺乏质量检验评定依据,影响了其健康快速发展。根据多年实践经验,对给水栓、进排气阀、安全阀、量水装置等附属设备和交叉建筑物、镇墩、防淤堵设施等附属建筑物给出了其质量检验内容和方法,仅供有关部门参考。     

A Novel Method for Agricultural Drought Risk Assessment

Climate change, increased temperatures and imbalanced precipitation distributions will potentially increase the local drought risk in certain areas. Drought assessment can identify the hidden dangers of drought and provide a theoretical basis for disaster prevention and mitigation. In this paper, a new agricultural drought risk assessment method proposed from the perspective of grain yield. The first principal components of precipitation, temperature, humidity and soil moisture represent hazard factors. The sensitive yield, which represents the sensitivity, was separated from the grain yield using a regression method. Additionally, the trend component of the grain yield represents the adaptive capacity, and the crop planting area represents exposure. Based on these definitions, the concepts of unit drought risk and regional drought risk are proposed. Four cities in Heilongjiang Province, which has the highest grain yield of any province in China, were used as application examples, and the spatial and temporal variation in the agricultural drought risk were analyzed. Application example show that the method for evaluating agricultural drought presented in this paper is reasonable in a statistical sense. The process for calculating sensitivity and adaptability shows that this method is suitable for arid and semi-arid areas, where grain yield is sensitive to hazard factors, and areas where grain yield has a certain trend.

     

河流水质综合评价的输水渠道模型

采用输水渠道模型对广东省第三大水系——鉴江水系中下游河段不同水质类别的水资源量进行演示计算，为区域水资源量与质的综合评价提出一种新的思路。     

Risk Assessment of Factors Influencing Non-Revenue Water Using Bayesian Networks and Fuzzy Logic

This paper aims to initially, identify effective factors of Non Revenue Water (NRW) and its three major components: apparent losses, real losses and non-revenue authorized consumptions in water distribution networks. In the next step, they should be ranked according to their potential in the reduction of the amount of NRW. Besides, incidence of each NRW components imposes some special economic and social impacts. In the present study, by considering data scarcity and uncertainty of the available data and information, risk assessment of NRW and its components has been done through two stages. The first stage is initiated by designing a questionnaire so as to collect data and information about 41 identified parameters in part of Tehran Water and Wastewater Company as the research pilot. Then, in order to demonstrate the probability relationships between factors influencing NRW components, Bayesian Network (BN) is used. At the end of this stage, the parameters are prioritized in terms of their impact. Through the following stage, consequences of NRW components existence are identified and fuzzified, to consider their uncertainty. After that, based on the risk definition and Fuzzy Inference Systems )FIS( concept, fuzzified probability and consequences are combined and NRW components’ risk is calculated. In this study, the calculated risk of NRW components in the study area are “Moderately High” and equal to 7.05, 6.95 and 6.4 for apparent loss, real loss and non-revenue authorized consumptions, respectively which means that decision makers and managers of this district should take serious actions to reduce the amount of risk.     

大伙房水库输水工程可调水量分析

浑江流域人均水资源占有量为4216m^3，每公顷水资源占有量为7.42万m^3，是水资源较为丰富的流域，可以考虑实施大伙房水库输水工程，把浑江丰富的水资源调往辽河中下游缺水地区。     

高坝风险分析的事件树法

新世纪一批高坝将要在我国开工建设,这对我国的水电能源及国民经济的发展有着不可估量的作用,而高坝建设中,安全性是需要首先保证的。目前对高坝的风险分析方法有主观概率法、客观概率法等。从系统工程的角度出发,采用事件树方法对高坝的风险进行了探索研究,并给出了算例以说明该方法的有效性和实用性。     

基于证据理论和可变模糊集的地下水环境风险评价

地下水系统的高维性和不确定性,给地下水环境风险评价带来较多困难,为提高评价的准确性和合理性,实现地下水的科学管理,该文将DS证据理论应用到地下水环境风险评价中,同时利用可变模糊集理论来构造证据理论基本信任分配,实现了客观合理的证据建模,最后利用经典组合原理进行证据组合。以希尼尔水库周边区域为例,地下水环境风险为中等时的信任区间为[0,0.33],似然区间为[0,0.35],不确定大小为0.02,根据判断规则,确定研究区地下水环境风险等级为中等。结果表明,该方法能够较好地融合地下水环境各方面信息以及处理风险评价中的不确定性,实现了地下水环境风险的准确评价。     

Assessment of River Water Quality Based on Theory of Variable Fuzzy Sets and Fuzzy Binary Comparison Method

There has been an increasing need for the proper evaluation of river water quality in order to safeguard public health and to protect the valuable fresh water resources. In order to overcome the own limitations of the traditional evaluations which can only use a point value instead of an interval for grading standards, on the basis of the fuzzy binary comparison method (FBCM) and the theory of variable fuzzy sets (VFS), an integrated variable fuzzy evaluation model (VFEM) is proposed for the assessment of river water quality in this paper. This model possesses the preciseness of the algorithm and operability in practice, can well solve the grading standards which are interval form. In order to explore and compare the present method with other traditional methods, two cases studies in the Three Gorges and Tseng-Wen River are made. The results show that the proposed VFEM method can convey water cleanliness to certain degree by using the eigenvector of level H, which is much stricter in the superior level, and that it can improve the veracity for the assessment of water quality.     

基于模糊综合评判法的洪水灾害风险评估

通过对洪水灾害评价指标危险性、暴露性、易损性以及防灾减灾能力4因子的分析,用模糊综合评判法构建了洪水灾害风险评估模型,利用该模型对湖州市下辖区县进行了风险评估,给出各区县的风险指标。并分析了各区县的风险类型和风险程度,为今后制定防洪规划、合理分配防洪减灾力量提供了科学依据。     

输水隧洞衬砌结构数值分析

衬砌设计作为隧洞设计中的重要环节,对保护隧洞长期稳定有重要作用,在初步拟定衬砌尺寸的基础上,通过理正软件对Ⅲ类、Ⅳ类和Ⅴ类围岩洞段典型断面的衬砌进行受力特性和配筋面积计算,并与Phase2的计算结果进行对比,理正计算得到的截面内侧和外侧所需配筋面积均比Phase2计算得到的截面所需总配筋面积小。     

胶东调水工程输水管道施工质量安全监控方法

胶东调水工程为全区域用水提供丰富的水资源,为保证输水管道输送效能,需要监控输水管道施工质量,保证调水工程顺利输送水资源。但由于传统监控方法拟定的监控指标单一,导致管道施工质量安全监控数据与实际数据不一致。文章对胶东调水工程,提出了全新的输水管道施工质量安全监控方法。该方法利用水域概化图模型,评价胶东地区调水工程水网连通度;通过计算输水管道冻胀参数与排水减压参数,获取施工实际指标;拟定三级监控指标,实现输水管道施工质量安全监控。实验测试结果表明:与两种传统监控方法相比,此次提出的监控方法,在多级监控指标的帮助下,其监控数据与实际施工数据保持一致。由此可见,此次提出的监控方法,能够有效掌握施工质量。     

上海市暴雨的模糊风险评价

暴雨或大暴雨是许多城市常见的一种自然灾害现象。采用模糊数学中的信息扩散方法，建立了用于暴雨模糊风险分析的模型，并以上海市近20年来的暴雨资料为例进行计算，计算结果证明了该模型的简便可行性，为今后上海市的暴雨灾害防治工作提供一定参考。     

基于模糊证据推理的南水北调工程突发事件风险评价

突发事件风险因子具有不确定性和模糊性。选取模糊正态分布函数改进了信度结构模型,结合证据推理方法构建了模糊证据推理评价模型,在此基础上,运用不变权重次约束模型对关键风险源进行诊断。以南水北调中线工程为例,构建了五等级风险模糊评价模型,在优选确定南水北调工程突发事件风险指标体系基础上,运用提出的模糊证据推理模型对南水北调中线工程突发事件风险进行评价,并进行了关键风险源诊断,研究结果与实际情况相符。     

穿越高速公路输水工程中盾构法的应用

在输水隧洞穿越八达岭高速公路时,为了保证路面下沉控制在一定的范围内,且保证地下管线的安全,采用盾构法施工方法。在穿越高速路时采用盾构隧道内注浆加固措施,提前进行地面雷达探测并保证施工的连续性;严格控制掘进土压力、掘进速度和出土量;严格控制盾尾同步注浆、二次补注浆和盾构掘进轴线,并采用合理的监控量测与应急预案。确保了输水工程高质量穿越八达岭高速公路,该方法和施工过程对于该类施工具有很好的示范和借鉴作用。