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911.
In case of large data matrices comparative evaluations of objects/regions with the technique of Hasse diagrams may be troublesome due to a messy system of lines in the graphical representation. Here fuzzy clustering leads to useful simplifications because regions with slightly different pollution pattern are grouped together. However, fuzzy clustering implies to introduce a threshold value for the membership of an object to a cluster and to select the best number of clusters. Therefore many arbitrarities evolve. Within the systematic study presented here we found that some objects are very stable against variations of the threshold value and the number of cluster whereas other objects behaves different. According to their behaviour we investigated a classification of the objects. Formal Concept Analysis shows that in some cases specific pollution pattern imply the membership to one of these classes. For example objects which are characterized by high Pb-, Zn-concentration and moderate S-concentration imply a high stability against variants of the clustering process. Further implications are described in the paper.  相似文献   
912.
This paper suggests a number of benefits in identifying urban and regional planners as a public in public participation programs of water resources planning studies. A perspective on public participation is presented. Recent trends and developing concepts are identified: emphasis on the need to coordinate urban and regional planning activities with water resources planning, increasing system complexity, the goals and objectives orientation of planning, planning for multi-objectives, the evaluation of a broader range of alternatives, and the consideration of water alternatives as only one set of measures to further society's aspirations. One way to assist in capitalizing on these trends is to seek out participation of those in other planning efforts who are involved in planning but on a different level. Because of their intimate knowledge of an areas history, growth and development, political climate, local perceptions of needs and desires, and major problems and issues they are able to contribute a great deal of insight in making the water resources planning effort more responsive at the local level. The paper describes one of the first major efforts at working-level public-planner contact which was carried out as part of the Susquehanna River Basin Study. A regional survey team comprised of an engineer and an economist from a federal agency and a state water resources planner met informally with planners, city managers, and local planning commissions to discuss issues related to water resources and the growth and development of local areas. This effort while only part of the overall public participation program yielded a number of benefits and if expanded and refined would be a very useful experience in other studies.  相似文献   
913.
In France and the United States it has been shown that strong linkages exist between vegetation and alluvial landforms within homogeneous river stretches characterized by geomorphological processes, flood duration, flood magnitude, flood frequency, and sediment size. Furthermore, perturbations induced by man (such as embankments and damming) have been shown to have an effect on both succession and plant distribution patterns. Yet, in numerous cases it is not possible to find either the communities or the plants whose presence might be predicted by reference to the river section characteristics (such as straight, braided, anastomosed, or meandering channels) or by reference to perturbation effects well known in piedmont valleys (such as variations of the water-table depth, variations of magnitude, and frequency and duration of floods). Unexpected species, new communities, and even new successional sequences are often observed. The presence of new alluvial forms explains these differences. An “artificial” substratum generated by an old human perturbation (limited in the time) has been established in the past; consequently, the natural distribution patterns of water and matter flows have been disturbed. Archive research has enabled a classification of abandoned systems that were commonly used during the 16th, 17th, 18th, and 19th centuries on European floodplains. Several case studies were chosen in order to illustrate and explain the importance of stream corridor history. The example of the Isère River valley, downstream from Albertville, is chosen to highlight the heterogeneity of the vegetation mosaïc pattern outside the dikes. The historical reconstruction explains the role of the additional disturbances that cause deviation from the system evolution patterns.  相似文献   
914.
As industrial operations expand, major incidents continue to affect people, damage facilities, and impact the environment. In the last 20 years, about 50% of these incidents occurred in facilities that had implemented some form of Process Safety Management (PSM) and 50% came about in smaller facilities that did not include such planning (Demichela et al., 2004). The objective of this article is to use PSM principles to create practical recommendations at the regional level, to complement those previously developed for singular facilities. This article compares Strathcona County Emergency Service (SCES) in Alberta with Technical Standards & Safety Authority (TSSA) in Ontario, with respect to safety, facility licensing, permit requirements, risk assessment procedures and land use planning aspects to determine PSM enhancements for SCES. Furthermore, for a better overview, two supplemental provincial organisations in Alberta, namely Alberta Boiler Safety Association (ABSA) and Safety Codes Council (SCC), were also considered. We proposed that SCES could develop more detailed facility-specific licensing procedures, auditing, and inspection. SCES could also provide details of accredited organisations that carry out inspections and audits on their behalf. When reviewing the quantitative risk assessment processes for SCES and TSSA, we recommend that SCES should update their probability data sources used in their cumulative risk assessment study. Based on the authors’ experience and gathered data, the use of additional facility practices such as safety management system, internal audits, and checklists can enhance incident prevention.  相似文献   
915.
为探究评估城市区域的火灾综合风险,提出空间聚类和层次分析法对深圳市盐田区2011年至2019年火灾数据进行建模分析。运用DBSCAN聚类模型对火灾地点进行分类,结合层次分析法构建火灾风险评估验证模型,探讨聚类结果、火灾场景、火灾原因构建系统层次结构模型,综合得出风险评估结果。通过将聚类区域还原至百度地图,结合场景信息及层次分析法指标值对模型的有效性进行验证。结果表明:由于各区区域功能及地理位置不同,区域火灾风险值有明显差异,模型计算出的4个区域结果与实际火灾情况具有一致性。  相似文献   
916.
为了综合判断区域工业行业的环境影响和经济效益,分别定义了工业环境影响评判系数和工业环境经济系数,建立了相应的数学模型,并以西安市为例进行研究.研究结果表明:电力、热力的生产和供应业以及造纸及纸制品业对西安市的环境影响最大,环境影响系数分别为0.332 2和0.304 6;环境经济系数较差的依次为黑色金属矿采选业、有色金属矿采选业、造纸及纸制品业、电力及热力的生产和供应业,环境经济系数分别为151.650 0、34.798 3、19.652 0、8.032 2.环境影响与经济效益评判模型的建立为区域环境管理和产业结构调整提供了依据.  相似文献   
917.
污染物排放强度反映了单位新创造经济价值的环境负荷大小。运用均方差赋权法对连云港市各县区的工业废水量、化学需氧量、氨氮、二氧化硫、烟尘、工业粉尘和工业固体废物等7种主要污染物排放强度的区域差异进行了评价;然后分别将各县区污染物排放强度的最小数值作为各地区污染物排放强度目标值,计算各县区的污染物排放强度降低潜力。结果表明,七种主要污染物排放强度综合评价的全市平均水平为1.30,市区污染物排放强度明显比县域的小;主要污染物排放强度减排潜力具有显著的区域间差异与区域内差异。最后从增加环境保护投资、改善能源使用结构、调整和优化产业结构和大力发展循环经济等方面提出了促进污染物排放强度降低的一些建议。  相似文献   
918.
北京及周边地区夏季大气颗粒物区域污染特征   总被引:9,自引:4,他引:5  
本地排放和区域传输共同影响着北京及周边地区的空气质量.2007年8月在北京清华大学、密云水库、河北任丘和内蒙古商都采集颗粒物样品并获得了PM2.5质量浓度和TSP中22种无机元素的时空分布特征. 4个观测点PM2.5质量浓度高低顺序为任丘>清华>密云>商都.二次污染元素S和一次污染元素Zn、Pb、Cu、As、Sb、Ni、Cd、In、Se在任丘的PM中含量最高,表明该观测点受人为源影响最为显著,其较弱的日变化幅度表明高浓度PM主要由本地源贡献;商都地区污染元素浓度随时间变化波动最为剧烈,受气象条件导致的传输影响较大;清华和密云的S、Pb、Cd、In、As、Zn的相关系数均大于0.70,其来源具有一定相似性;在锯齿型污染过程的开始和结束,密云各元素浓度值达到和区域背景点商都观测期间最低值相近的水平,表明密云可以表征西北洁净空气的区域特征; PM峰值阶段,整个地区高浓度硫酸盐的均匀分布(约10 μg/m3)证实了锯齿型区域污染的二次性本质.结合元素富集因子的不同分布特征讨论了各地区PM的可能来源及相互影响  相似文献   
919.
依据区域可持续发展的内涵,针对区域整体提出了一套简便的、操作性强的、定量的模糊层次分析法评价模式,使评价结果显得更加科学、合理,帮助削定和选择维护该区域及周围环境良性循环和经济可持续发展的最佳行动方案,为区域开发规划的制订与调整以及区域环境管理提供一定的理论依据。  相似文献   
920.
延吉市综合环境承载力研究   总被引:2,自引:0,他引:2  
环境承载力对于指导人类社会经济活动,协调人类发展与环境的关系具有十分重要而迫切的理论与现实意义。本世纪是城市飞速发展的世纪,环境问题是城市问题的主题和核心。近年来延吉市的经济增长呈现了良好的态势,但是环境污染和生态破坏问题却日益威胁到了经济与社会环境的协调发展。以延吉市为研究对象,结合环境规划的需要,从理论上阐述了环境承载力的概念,通过建立指标体系,应用环境承栽力的计量模型,对延吉市2006年、2007年综合环境承栽力进行了初步分析,研究表明,延吉市综合环境承载力处于可持续状态并趋于最优值(Qk=0.475)。  相似文献   
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