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41.
Water Network Synthesis Using Mutation-Enhanced Particle Swarm Optimization   总被引:2,自引:0,他引:2  
Different techniques for the synthesis of industrial water reuse/recycle networks have been developed in recent process integration research. These tools range from graphical pinch analysis approaches to mathematical programming models. The latter have the advantage of being flexible enough to incorporate various water network constraints, but in many cases these are often non-linear, thus making the identification of global optima difficult. Recent work has demonstrated the effectiveness of metaheuristic algorithms such as particle swarm optimization (PSO), for finding good solutions these problems. This work describes the use of a modified PSO for solving mixed integer non-linear programming (MINLP) models for water network synthesis. By incorporating a mutation operator for the binary variables in the model, the algorithm is able to escape sub-optimal network topologies and proceed towards better solutions than can be found with ordinary PSO. Two case studies involving water recycle/reuse are used to demonstrate the new design methodology.  相似文献   
42.
重点论述社会主义市场经济条件下的企业全员安全管理的概念、特点和基本要求,企业开展全员安全管理的重要性,应遵循的原则和实施措施。  相似文献   
43.
The work highlights the difficulties of using standard sampling and statistical techniques to investigate regional phenomena and presents an integrated approach combining small-scale sampling with broad-scale observations to provide input into a modeling exercise. It is suggested that such approaches are vital if landscape- and regional-scale processes are to be understood and managed. The way in which the problem is perceived (holistically or piecemeal) affects the way treatments are designed and their effectiveness: past approaches have failed to integrate the various scales and processes involved. Effective solutions require an integrated holistic response.  相似文献   
44.
空间功能识别是确定国土空间规划空间开发保护格局的关键环节,理论和实践意义重大。基于土地利用和地表覆盖现状、精细化DEM、地形单元等基础地理信息,水、生态、环境、灾害等专题数据,社会统计数据等多元信息,利用空间分析、多元统计、计量模型、基于规则的分类模型等技术方法,从多元信息综合集成和自动分类识别的角度,研究构建了一套市县国土空间规划空间主导功能识别的关键技术与方法,并对榆林市域进行空间功能分区。研究表明:本文方法有效将地理实体单元、功能评价指标综合于统一的地域单元,保证了空间功能分类识别的准确性;通过自动分类算法建模,实现空间功能识别的自动化,提高了国土空间规划的客观性和工作效率。  相似文献   
45.
酒泉地区城镇类型较多,城镇体系中的许多关系需要统筹协调,本文侧重从城镇的规模和空间关系分析,城乡一体化和区一发展,基础产业和环境建设等三个角度,探讨了区域城市可持续发展问题。  相似文献   
46.
National authorities in many countries aim at having climate change adaptation mainstreamed into existing policy domains in order to achieve coherence and synergies, and to avoid mal-adaptation. Because of local variations in climate change impacts, the lion's share of climate adaptation work will have to take place at the local level. This means also that the mainstreaming process needs to occur locally. This article examines the mainstreaming of climate change adaptation into existing sectors in five Norwegian municipalities. Applying theories of mainstreaming and policy integration we find that policy development is slower, but perhaps more robust in the municipalities that have chosen a horizontal, cross-sectoral approach to mainstreaming than in the municipalities that have chosen a vertical sector approach to mainstreaming.  相似文献   
47.
通过分析重庆市环境监察现场执法业务应用需求,结合现有的信息化现状及信息技术发展趋势,设计了“一个平台、一个中心、两个体系”的系统总体架构,提出了“移动端防控、链路安全、内网和服务器防护”的网络传输和信息安全系统设计,采用VPN专网,有效解决了符合三级等保安全的移动设备的传输网络,采用虚拟化的云服务平台,研发了市-区两级的重庆市环境监察移动执法系统,并在市局、涪陵和九龙坡区试点应用,取得了很好的应用效果。  相似文献   
48.
This paper develops a methodology for integrating a land-use forecasting model with an event scale, rainfall-runoff model in support of improving land-use policy formulation at the watershed scale. The models selected for integration are loosely coupled, structured upon a common GIS platform that facilitates data exchange. The hydrologic model HEC-HMS is calibrated for a specific storm event that occurred within central Washington State. The land-use forecasting model, What If? is implemented to forecast future spatial distributions of low-density residential land-uses under low and high population growth estimates. Forecasted land-use distribution patterns for the years 2015, 2025, and 2050 are then used as land-use data input for the calibrated hydrologic model, keeping all other parameters constant. Impacts to the stream discharge hydrograph are predicted as the study area becomes increasingly developed as forecasted by What If?. The initial results of this integration process demonstrate the synergy that can be generated through the linkage of the selected models. The ability to quantifiably forecast the potential hydrologic implications of proposed land-use policies before their implementation offers land-use decision-makers a valuable tool for discerning which proposed land-use alternatives will be effective at minimizing storm water runoff.  相似文献   
49.
长三角一体化高质量发展对于中国经济行稳致远有着不言而喻的重要意义。为了科学全面认识新时代长三角一体化高质量发展中存在的问题,厘清未来的发展出路,邀请来自不同领域的相关专家就长三角一体化高质量发展中的区域协调、产业协同、交通组织、城镇体系演变、跨区合作、要素配置、流域统筹、一体化路径、绿色低碳发展等研究前沿进行访谈。访谈结果表明:长三角作为我国经济发展最活跃、开放程度最高、创新能力最强的区域,其发展中仍然存在内部发展不平衡、区间交通割裂、行政壁垒尚存、流域生态协作不健全、产业协同发展不足、绿色经济体系较弱等突出问题。长三角在中国乃至世界发展格局中的战略地位,需要综合各学科各专业的理论知识,从不同视角持续关注长三角一体化高质量发展的重大科学命题。紧扣“一体化”和“高质量”,长三角一体化首先要创新机制缩小区域内部发展差异,强化综合交通一体化的基础支撑,更要突破行政边界的制约;其次要创新机制体制来保障生产要素的有效流动与配置,通过价值链、产业链、创新链的融合发展来夯实一体化;再次要促进土地要素向长三角集中使用,提高长三角地区土地承载能力,为长三角区域一体化高质量发展提供充足的土地要素保证;然后要优化人口就业空间结构,加强城际间环境污染联防联治,强化大江大河等重大流域的省际统筹与合作,共同提升长三角的生态系统服务功能,推动绿色一体化发展;最后更要贯彻五大新发展理念,通过科研突破与市场机制来实现低碳发展,在创新驱动引领下打造流空间世界级枢纽,以实现长三角区域一体化高质量发展的新局面。以上观点为长三角区域一体化高质量发展提供科学可行的理论和决策支持。  相似文献   
50.
This paper introduces the problems of a market-driven waste management strategy in the UK and the momentum towards developing markets for recycled materials. It focuses on the demand side barriers and principally the need for market stimulation in the end uses for recyclables. The important role, which small- and medium-sized manufacturing enterprises (SMEs) have to play in developing existing markets for recyclate, is discussed. SMEs also have the potential to contribute to the radical new approach of identifying and developing a broad range of new, more diverse and higher value uses for recyclate. If these enterprises are to be engaged effectively then regional action is essential. The paper then reports on research work focusing on SMEs that has taken place as a component of the CWMRE (Creating Welsh Markets for REcyclate) market development initiative in Wales. As a foundation for this, a series of semi-structured interviews with SMEs has been conducted with those operating in sectors that are known to have the potential to provide novel applications for secondary materials or to have the potential for material displacement. Some of the barriers and corresponding needs within the case study companies involved are discussed. The implications of these findings for a regional market development programme are considered and in particular how these case studies support the need to engage SMEs in the use of secondary materials.  相似文献   
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