污水处理SCADA系统中的GSM通讯

针对污水处理系统的特点与要求,探讨了SCADA系统中使用的GSM无线通讯网络,对其典型的两种数据传输模式(利用PPP协议拨号上网的GPRS无线数据分组业务及GSM短消息业务)分析了数据传输方式、通讯流程及两种模式的优缺点。并在上海松江东西部地区分别实现了这两种传输方式,效果良好。     

基于B—P神经网络优化算法的城市环境空气中PM10浓度预测模型

将B—P神经网络应用于西安市环境空气中P10浓度预测,对网络结构和算法进行了优化,建立了PM10浓度预测模型。经验证模型精确度比较高,PM10日平均浓度绝对误差0．015～0．020mg／m^3,相对误差在-20％～20％范围内。     

An environmental pressure index proposal for urban development planning based on the analytic network process

This paper introduces a new approach to prioritize urban planning projects according to their environmental pressure in an efficient and reliable way. It is based on the combination of three procedures: (i) the use of environmental pressure indicators, (ii) the aggregation of the indicators in an Environmental Pressure Index by means of the Analytic Network Process method (ANP) and (iii) the interpretation of the information obtained from the experts during the decision-making process.The method has been applied to a proposal for urban development of La Carlota airport in Caracas (Venezuela). There are three options which are currently under evaluation. They include a Health Club, a Residential Area and a Theme Park. After a selection process the experts chose the following environmental pressure indicators as ANP criteria for the project life cycle: used land area, population density, energy consumption, water consumption and waste generation. By using goal-oriented questionnaires designed by the authors, the experts determined the importance of the criteria, the relationships among criteria, and the relationships between the criteria and the urban development alternatives.The resulting data showed that water consumption is the most important environmental pressure factor, and the Theme Park project is by far the urban development alternative which exerts the least environmental pressure on the area. The participating experts coincided in appreciating the technique proposed in this paper is useful and, for ranking ordering these alternatives, an improvement from traditional techniques such as environmental impact studies, life-cycle analysis, etc.     

一种用于电力通信的自适应Adhoc协议

针对电网通信的智能化监测应用需要,提出了一种用于电力通信的Adhoc自适应预约按需传输多址接入协议,该协议在接入阶段可以根据业务量动态调整接入策略;在传输阶段可以无冲突的发送分组.针对该协议的吞吐量和平均时延性能进行了仿真分析.分析结果表明：协议能提高信道利用率、降低接入时延,可用于现代电力通信网络,以上研究结果对Adhoe在电力通信的工程中应用有较好参考意义.     

基于贝叶斯网络的高速动车组运营故障分析

为研究影响高速动车组正常运行的各故障因素间的因果关系，分析其耦合强度，将故障因素分为人、机、环3类，从系统角度又将机器因素分为5个子系统。人、机、环3类共识别27个故障因素；使用K2算法生成贝叶斯网络结构，引入扩展因果效应算法确定节点优先次序作为K2算法的先验知识，采用EM算法学习贝叶斯网络参数，构建基于贝叶斯网络的高速动车组运营故障分析模型；以209个CRH详细故障报告为例，对故障因素的故障发生概率进行排序并分析因素间的影响强度和灵敏度。结果表明:牵引供电系统故障发生概率较高；车门系统故障、牵引变流器故障易由内部零件故障引起，外界异物击打对受电弓影响较大；人、环因素更易引起多故障耦合；环境因素对牵引供电系统表现出较高的灵敏度。贝叶斯网络在分析高速动车组运营系统故障问题上具有可行性，分析结果有助于提升运营单位的管控能力。     

Model reduction via principal component truncation for the optimal design of atmospheric monitoring networks

A numerically efficient methodology for the optimal design of monitoring networks aiming at the surveillance of accidental atmospheric release is proposed in this paper. In a realistic context, the design of such a network requires the knowledge of a database of potential dispersion accidents occurring in the domain of the study. An objective function measures the ability of a potential network to provide measurements in order to reconstruct any accidental plume taken from the database. In the optimisation of such cost functions with respect to networks, most of the computational time is spent in the evaluation of the function, especially if the accidents database is large. In this paper we show how to optimally reduce this database and how this affects the design via a mathematical expansion in the cost function. We introduce methods based on principal component analysis, which are rigorous when the cost function is of least-squares type. These methods are then tested and validated with success on the design of a radionuclides monitoring network to be deployed over France. This is the so-called Descartes network which will be operated by the French Institute for Radiation and Nuclear Safety. These techniques are then applied on Descartes to solve several issues that are computationally demanding, but are also of more general interest, such as: how should one sequentially deploy the stations of the network? How is affected the optimal network when other European potential radiological sources are taken into account?     

An Evaluation of Qualitative Indexes of Physical Habitat Applied to Agricultural Streams in Ten U.S. States1

Hughes, Robert M., Alan T. Herlihy, and Philip R. Kaufmann, 2010. An Evaluation of Qualitative Indexes of Physical Habitat Applied to Agricultural Streams in Ten U.S. States. Journal of the American Water Resources Association (JAWRA) 46(4): 792-806. DOI: 10.1111/j.1752-1688.2010.00455.x Abstract: Assessment of stream physical habitat condition is important for evaluating stream quality globally. However, the diversity of metrics and methods for assessing physical habitat condition confounds comparisons among practitioners. We surveyed 51 previously sampled stream sites (0.0-6.3 m wide) located in regions of row-crop agriculture in Oregon, California, North Dakota, South Dakota, Nebraska, Iowa, Minnesota, Pennsylvania, Maryland, and West Virginia to evaluate the comparability of four indexes of physical habitat condition relative to each other. We also compared the indexes to previously calculated indexes of fish and macroinvertebrate condition. The physical habitat indexes included the Stream Visual Assessment Protocol Version 2 of the Natural Resources Conservation Service, the qualitative habitat evaluation index of the Ohio Environmental Protection Agency, the rapid bioassessment protocol of the United States Environmental Protection Agency (USEPA), and a qualitative physical habitat index based on USEPA quantitative physical habitat measurements. All four indexes were highly correlated with each other, but low-to-moderately correlated with biotic index scores for fish and macroinvertebrate assemblages. Moderately high correlations occurred between some macroinvertebrate biotic index scores and quantitative metrics. We conclude that additional research is needed to increase the predictive and diagnostic capabilities of qualitative physical habitat indexes.     

协定水污染物间接排放标准的法律问题探究

以协商的方式确定水污染物间接排放标准的规定打破了人们对标准确定性、强制性的传统认识。协定标准的优势在于充分利用污水处理厂的污水处理能力,减轻企业的污水处理负担,使企业可以集中力量搞生产。协定标准具有灵活性和优越性,应充分利用。通过对协定标准概念和重要性的分析,指出协定标准存在效力不确定、缺少对协定范围的限制等问题,造成协定标准在实践中通常被忽视或者滥用。并从明确协定标准的范围、加强排污企业的管理和协定标准的监督等方面,进一步提出了限制和完善水污染物间接排放标准的建议。     

基于STPA和模糊BN的装配式建筑吊装施工安全风险分析*

为有效评估装配式建筑吊装施工中的安全风险状态,识别关键风险因素,运用系统理论过程分析方法(STPA)构建吊装施工过程中的控制反馈结构,识别导致危险的不安全控制行为,确定不安全控制行为的致因因素;基于风险因素间的关联关系构建贝叶斯网络（BN）模型,推理计算装配式建筑吊装施工安全风险状态概率,并结合反向诊断推理分析影响安全事故的风险因素;通过敏感性分析,识别装配式建筑吊装施工安全中的关键风险因素。结果表明:装配式建筑吊装施工安全风险处于低风险状态;起重机械超负荷运行、现场安全管理不到位和吊索吊具存在缺陷等因素是影响装配式建筑吊装施工安全风险的关键风险因素。     

基于改进K-means和CNN的储罐罐底点蚀诊断模型*

为解决储罐罐底点蚀问题,提出基于改进K-means和CNN的储罐罐底点蚀诊断模型,在传统聚类基础上引入肘部法则,保证k值选取3的准确性,将原始声发射信号特征参数和聚类后的类别信息输入模型进行训练,系统预测准确率高达99%。研究结果表明:该模型能够及时发现点蚀现象,指导管理者确定储罐开罐检查时间顺序,避免点蚀穿孔造成的人力、物力损失,降低储罐运行风险,保障储罐运行安全,研究结果可为罐底点蚀诊断提供技术支撑。