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191.
计算机决策支持系统已经比较成熟地应用于许多行业,但在生态工业园建设管理中尚未得到应用。本文结合生态工业园建设管理的特点,分析了生态工业园决策支持系统开发的功能要求,提出了一种基于GIS、数据仓库、数据挖掘以及联机分析技术,并结合专家系统的生态工业园智能决策支持系统的框架,探讨了决策支持系统在生态工业园建设管理中的发展前景。  相似文献   
192.
水质污染总量的合理分配研究   总被引:1,自引:0,他引:1  
水质污染总量削减分配的目的应该是实现各种资源的合理组合和高效利用.本文利用运筹学中的DEA方法,对企业的经济、管理及排污三个方面的素质进行了评价,进而形成企业素质综合指数.企业素质综合指数为我们确定总量控制对象和总量削减分配权重提供了必要的依据.  相似文献   
193.
Risk analysis for production processes in the petrochemical industry is an important procedure for consequence prediction and investigation of accidents. The analyzer must grasp the correlations between the possible causes and consequences. From the potential cause and effect found in risk analysis reports, complete clarification should be obtained. Therefore, this study presents a method for assisting accident consequence prediction and investigation in the petrochemical industry based on risk analysis reports using natural language processing technology. First, a hazard and operability (HAZOP) historical data table is established by filling over 7200 HAZOP analysis data points. Both the causes and consequences in the table are classified into 20 categories each using the Latent Dirichlet Allocation (LDA) models. The LDA clustering results are assigned classification for the cause and consequence topics to the cause and consequences of the HAZOP analysis data. Based on part-of-speech (POS) tagging, all the words in each cause and consequence record are divided into subject and action words. Next, the word combinations of subject and action words with a higher occurrence are considered the key phrases for describing and representing the corresponding cause and consequence topic classifications. The Apriori algorithm is used to determine the frequent item sets, acquire the association rules, and calculate the association degree to obtain the sort order; it can highlight general trends in relational cause and consequence topics. According to the results, the most likely cause of the consequence and the most likely consequence that the cause may lead to are identified. Finally, a visual interface is developed to present the data for the consequence prediction and cause investigation of accidents. The results reveal that the quantity and quality of historic data are important factors that may influence the results. This method can contribute to predicting the accident evolution trend of an abnormal situation, taking preventive measures in advance, improving the accuracy of early warning, and supporting emergency response measures.  相似文献   
194.
Collecting municipal solid waste (MSW) is a major and expensive task for local waste management authorities, thus efficient MSW collection is a necessity. This study presents a procedure for developing an aggregate indicator (AI) to assess MSW collection efficiency based on multiple factors. The applicabilities of various key performance indicators (KPIs) are evaluated based on five selection criteria, and five KPIs are chosen to form the AI. The relative efficiencies of local MSW collection services are analyzed by the data envelopment analysis (DEA) method. A set of common weights for all five KPIs is then generated based on DEA results and four selection rules by modifying a previous approach. Finally, the proposed AI is applied to assess the MSW collection services provided by 307 local governments in Taiwan, and associated results are compared and discussed.  相似文献   
195.
The Suzhou Creek Rehabilitation Project (SCRP) is one of the largest water-related environmental rehabilitation schemes ever undertaken in the vicinity of Shanghai, China. This paper details the development and application of a River Environmental Decision Support System (REDSS) for scientific planning and decision-making on the Suzhou Creek project, and illustrates the flexibility of the REDSS framework. We developed the following components: (1) a GIS-based analysis employing Component technology; (2) a "data mart" for multi-dimensional, multi-level, integrated, dynamic, and flexible data querying; and (3) a set of hydrodynamic and water quality models which can simulate complex tidal river networks. In addition, we detail how a water quality assessment model is embedded into the REDSS by employing an Identification Index Method. With the REDSS, all GIS and non-GIS components are integrated seamlessly and data from different sources can be queried simultaneously. This allows for various scenarios to be simulated and analyzed in advance to predict and assess the effects of proposed engineering and management measures. Generated information can thus support effective decisions. All operations of the REDSS can be implemented conveniently through user-friendly interfaces. The function of the REDSS framework is demonstrated through an application to Suzhou Creek. Because the REDSS characteristics are quite general, it may be applied in different geographic regions.  相似文献   
196.
Recent policy changes within the Common Agricultural Policy have led to a shift from a solely production-led agriculture towards the promotion of multi-functionality. Conversely, the removal of production-led supports would indicate that an increased concentration on production efficiencies would seem a critical strategy for a country's future competitiveness. This paper explores the relationship between the 'multi-functional' farming attitude desired by policy makers and its effect on technical efficiency within Scottish dairy farming. Technical efficiency scores are calculated by applying the non-parametric data envelopment analysis technique and then measured against causes of inefficiency. Amongst these explanatory factors is a constructed score of multi-functionality. This research finds that, amongst other factors, a multi-functional attitude has a significant positive effect on technical efficiency. Consequently, this seems to validate the promotion of a multi-functional approach to farming currently being championed by policy-makers.  相似文献   
197.
Managing diffuse water pollution from agricultural land continues to be one of the more intractable challenges for environmental policy. The advent of the Water Framework Directive places the onus on EU member states to identify reasons why water bodies fail or are at risk of failure to meet good ecological status. In such cases, programmes of measures are to be enacted to mitigate the causes at least cost. Failing this, users may ultimately be faced with the full costs of pollution. This paper considers the scope for measures that address nitrogen and phosphorus pollution at source. Specifically the paper relates the diffuse pollution problem to the extent of over application of nitrogen and phosphorus. Data envelopment analysis applied to English cereal and dairy farmers, provides an indication of resource use and evidence of over application. This inefficiency provides a potential basis for either a least cost abatement approach using effective information and advice, or alternatively a pollution charge.  相似文献   
198.
The importance of riparian vegetation to support stream function and provide riparian bird habitat in semiarid landscapes suggests that standardized assessment tools that include vegetation criteria to evaluate stream health could also be used to assess habitat conditions for riparian-dependent birds. We first evaluated the ability of two visual assessments of woody vegetation in the riparian zone (corridor width and height) to describe variation in the obligate riparian bird ensemble along 19 streams in eastern Oregon. Overall species richness and the abundances of three species all correlated significantly with both, but width was more important than height. We then examined the utility of the riparian zone criteria in three standardized and commonly used rapid visual riparian assessment protocols—the USDI BLM Proper Functioning Condition (PFC) assessment, the USDA NRCS Stream Visual Assessment Protocol (SVAP), and the U.S. EPA Habitat Assessment Field Data Sheet (HAFDS)—to assess potential riparian bird habitat. Based on the degree of correlation of bird species richness with assessment ratings, we found that PFC does not assess obligate riparian bird habitat condition, SVAP provides a coarse estimate, and HAFDS provides the best assessment. We recommend quantitative measures of woody vegetation for all assessments and that all protocols incorporate woody vegetation height. Given that rapid assessments may be the only source of information for thousands of kilometers of streams in the western United States, incorporating simple vegetation measurements is a critical step in evaluating the status of riparian bird habitat and provides a tool for tracking changes in vegetation condition resulting from management decisions.  相似文献   
199.
十二五"期间全国PM_(10)浓度陡增导致了达标城市比例降低,影响了《国家环境保护"十二五"规划》空气质量指标的完成。通过对PM_(10)浓度时间和空间变化分析,得出《环境空气质量标准》(GB3095-2012)的逐步实施对全国PM_(10)浓度的异常变化有着显著影响。新标准的发布施行,促进了PM_(10)监测仪器和方法更新升级,大幅收严了监测数据统计的有效性,提升了监测数据的质量控制水平,从主观和客观上更加有效的提高了监测数据的精度。  相似文献   
200.
为了揭示有关长江研究的热点与发展动态,以Web of Science数据库为资料来源,利用文献计量学方法及TDA软件,对1900~2012年长江研究文献的发文量、国家、机构、作者、期刊、学科、关键词进行数据统计与分析。结果表明:(1)长江研究大致分为3个阶段:初步发展时期;探索时期;快速发展时期;(2)中国发表的关于长江研究的论文最多,国外主要国家及机构来自美国、日本、澳大利亚;(3)中国科学院是国内长江研究的主要机构;(4)国内外十分关注地质学、环境科学、水资源和气象学的研究。  相似文献   
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