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521.
基于覆盖水量的监测点优化选址法的缺陷与改进   总被引:1,自引:0,他引:1  
研究了给水管网水质监测点选址的方法,分析了覆盖水量法存在的缺陷,针对这一缺陷,提出了一种基于覆盖水量指数的改进方法,在评价节点的代表性时,该方法同时考虑了总覆盖水量和覆盖水量时间分布对节点代表性的影响,提高了管网水质监测点优化选择的准确度和监测数据的代表性.为了提高优化问题求解的速度,采用了遗传算法求解水质监测点优化选址问题,并将此两类方法应用于2个案例管网.对于案例中的管网,采用布设7个监测点,可有效监控所有95个节点中85%以上的管网水量.同时,实际案例管网的应用表明,与覆盖水量法相比,覆盖水量指数法的计算结果具有更好的代表性,基于此建立的给水管网在线监测网络能够更好地代表管网的水质情况.  相似文献   
522.
危险品道路运输量逐年增加,运输过程中一旦发生泄漏就会给人类安全健康、自然环境和社会带来巨大的危害.提出了危险品运输应急支持系统的设计构想,并从决策支持系统(DSS)中数据库和模型库两方面进行了分析,同时利用ALOHA和ArcGIS初步实现了系统的功能,为应急辅助决策提供一定的指导.  相似文献   
523.
公共场所事故以人群聚集为条件,人群风险的控制和减缓不同于一般工业危险源风险,不确定性和随机性大,风险触发因子较多,难以控制.将人群聚集风险影响因子归结为心理扰动因素和物理扰动因素两大类,并用综合扰动强度表示两者之和.通过对公共场所内火灾、爆炸、中毒、结构失效以及人群拥挤踩踏5类事故统计资料的分析表明,5个影响因子满足林德伯格条件,依据中心极限定理,综合扰动强度可以近似用1个正态分布加以描述.以火灾事故发生的研究作为基础,推广到其余4个因子,通过李雅普诺夫定理得出公共场所中综合扰动强度的概率密度函数,并通过傅立叶级数将其表征为多个余弦函数的线性组合,并根据统计资料进行了实例分析.最终该方法可以通过某一类型公共场所的事故发生次数,得到统计平均意义下,该场所周边环境存在的各种扰动因素对聚集人群影响的大小.  相似文献   
524.
Government interventions have been identified as important for energy systems change, because they can either facilitate or hinder transitions toward more sustainable energy systems. This article analyses how bioenergy options have been framed in Finnish policy strategies and how the framing has changed over time. The empirical material includes the content of 15 government programmes and nine national energy/climate strategies. On the basis of this assessment, both the link between bioenergy framings in strategies and the actual transformation of Finnish bioenergy systems are explored.On the basis of bioenergy framings, the development of energy policy can be divided into three phases: support for domestic energy sources in 1979-1991, support for wood- and industry-based bioenergy in 1992-1998, and diversified bioenergy in the context of climate change in 1999-2010. For two decades, primarily wood-based bioenergy was supported despite alternative technological developments occurring elsewhere. After the turn of the millennium, the importance of climate policy increased and alternative bioenergy sources were raised on the government policy agenda, also resulting in some new policy instruments. Rather than adopting a visionary outlook to guide system transformation, climate and energy policy has strengthened those technological options that have been selected elsewhere. If public policies are to enhance the shift toward low-carbon, sustainable energy systems, they would need to be more comprehensive, be more consistent over time, and emphasise energy use more.  相似文献   
525.
介绍了专家系统在火电厂湿法烟气脱硫系统中的作用,利用ACCESS建立了湿法烟气脱硫专家系统的知识库;以Visual Basic 6.0语言为开发工具,对湿法烟气脱硫专家系统软件进行了开发,该软件具有专家帮助功能、故障诊断功能、工艺仿真功能、知识库管理功能等。  相似文献   
526.
为分析ISC3模式中参变量的相对重要性及各参变量对模式预测结果的影响程度,采用2000年北京市全年气象统计资料,利用ISC3模拟火电厂高架点源排放,对应用广泛的ISC3空气质量模式进行了误差和灵敏度分析,结果表明:高架点源预测过程中,源强、风速、混合层高度和稳定度类型对模拟结果影响较显著,且为全程影响;排放温度、排放速度和环境温度在近距离影响较显著,对于远距离影响较小。  相似文献   
527.
流域水资源丰富度评价的MFP模型及应用   总被引:1,自引:0,他引:1  
水资源系统与许多因素有关,如各种水资源量、人口、社会经济发展指标等,它们共同组成了一个典型的复杂非线性系统。以最大流原理为基础,导出了描述水资源系统的信息动力学演化方程,建立了水资源评价的信息动力学模型,运用信息动力学模型建立了评价标准。该模型无需人为给定参数,客观性强,操作简便。最后运用理论模型对辽西沿海诸河流域水资源丰富度进行评价分析,得到各流域的丰富度状况,并与其它模型评定结果做出了比较,结果表明该方法具有较好的合理性和可操作性。由于该模型从一定程度上体现了水资源丰富度系统的演化动力学机理和水资源系统时空演变特性。因此,不仅在评价上有较大的优越性,在水资源丰富度发展变化状态的预测上也具有潜力。  相似文献   
528.
Today, energy occupies a pivotal position around which all socio-economic activities revolve. No energy means no life, and supply of energy in a cheap, plentiful, long-sustainable and environmentally safe form is a boon for everyone. In the light of rising cost of oil and fears of its exhaustion coupled with increased pollution, the governments worldwide are deliberating and making huge strides to promote renewable energy sources such as wind. Integration of wind machines with the diesel plants is pursued widely to reduce dependence on fossil-fuel-produced energy and to reduce the release of carbon gases that cause global climate change. The literature indicates that commercial/residential buildings in the Kingdom of Saudi Arabia (KSA) consume an estimated 10–40% of the total electric energy generated. The aim of this study is to analyse wind-speed data of Dhahran (East-Coast, KSA) to assess the economic feasibility of utilising autonomous hybrid wind–diesel power systems to meet the electrical load of 100 typical residential buildings (with annual electrical energy demand of 3512 MWh). The monthly average wind speeds range from 3.3 to 5.6 m/s. The hybrid systems simulated consist of different combinations of 600 kW commercial wind machines supplemented with diesel generators. The National Renewable Energy Laboratory's hybrid optimisation model for electric renewables software was employed to perform the techno-economic analysis.

The simulation results indicate that for a hybrid system comprising 600 kW wind capacity together with a 1.0 MW diesel system (two 500 kW units), the wind penetration (at 50 m hub-height, with 0% annual capacity shortage) is 26%. The cost of generating energy (COE, $/kWh) from this hybrid wind–diesel system was found to be 0.070 $/kWh (assuming diesel fuel price of 0.1 $/l). The study exhibits that for a given hybrid configuration, the number of operational hours of diesel generator sets (gensets) decreases with an increase in the wind-farm capacity. Concurrently, emphasis has also been placed on wind penetration, un-met load, effect of hub-height on energy production and COE, excess electricity generation, percentage fuel savings and reduction in carbon emissions (relative to diesel-only situation) of different hybrid systems, cost breakdown of wind–diesel systems, COE of different hybrid systems, etc.  相似文献   
529.
In this work, design for environment (DfE) methodologies have been used as a tool for the development of a more sustainable supply chain. In particular by combining life‐cycle assessment (LCA) techniques and by using the quality function deployment (QFD) multi‐criteria matrices, an ‘environmental compromise’ can be reached. In this work, the QFD matrices have been developed in a new way using an iterative process that involves the whole supply chain starting from the product life‐cycle, taking into consideration the machines that make the product and their components. This methodology is compatible with the requirements of the various stakeholders, suppliers, manufacturers and clients, involved in the supply chain. To assess the validity of the proposed approach a specific supply chain was studied concerning packaging systems for liquid food substances (beverage cartons). Firstly all the stages which are most critical from the environmental point of view in the supply chain of packaging systems were identified and assessed. The starting point for the analysis of environmental aspects and impacts which characterise the supply chain was LCA, which proved to be useful for the identification and the environmental assessment of the various stages in a packaging system. Through the use of ‘iterative QFD’ it is possible to arrive at a definition of the engineering characteristics of all the machinery which is involved in the supply chain. In particular in this work the authors have tried to identify the critical points in the design of those machines which either make the beverage cartons or are involved in the filling process.  相似文献   
530.
The role of energy in the present world is critical in terms of both economical development and environmental impact. Renewable energy sources are considered essential in addressing these challenges. As a result, a growing number of organisations have been adopting hybrid renewable energy system (HRES) to reduce their environmental impact and sometimes take advantage of various incentives. When a HRES is being planned, the ability to model a HRES can provide an organisation with numerous benefits including the capability of optimising sub-systems, predicting performances and carrying out sensitivity analysis. In this paper, we present a comprehensive system dynamics model of HRES and combined heating and power (CHP) generator. Data from a manufacturing company using HRES and CHP generator are used to validate the model and discuss important findings. The results illustrate that the components of a HRES can have conflicting effects on cost and environmental benefits; thus, there is a need for an organisation to make trade-off decisions. The model can be a platform to further simulate and study the composition and operating strategies of organisations that are venturing to adopt new or additional HRESs.  相似文献   
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