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1.
为了对钢铁企业安全投资进行模糊综合评价,建立了钢铁企业安全投资的评价体系,确定各因素的权重。得出模糊综合评价矩阵,可对各因素进行评价分析;得出某钢铁企业安全投资现状分数为83.9分,等级为较好,需着重加强安全培训、劳保品、工业卫生等人因素方面的投资;在环境方面的投资较合理。  相似文献   
2.
ABSTRACT: Two dynamic programming models — one deterministic and one stochastic — that may be used to generate reservoir operating rules are compared. The deterministic model (DPR) consists of an algorithm that cycles through three components: a dynamic program, a regression analysis, and a simulation. In this model, the correlation between the general operating rules, defined by the regression analysis and evaluated in the simulation, and the optimal deterministic operation defined by the dynamic program is increased through an iterative process. The stochastic dynamic program (SDP) describes streamflows with a discrete lag-one Markov process. To test the usefulness of both models in generating reservoir operating rules, real-time reservoir operation simulation models are constructed for three hydrologically different sites. The rules generated by DPR and SDP are then applied in the operation simulation model and their performance is evaluated. For the test cases, the DPR generated rules are more effective in the operation of medium to very large reservoirs and the SDP generated rules are more effective for the operation of small reservoirs.  相似文献   
3.
中国可持续社会养老保险的综合评价体系和实证分析   总被引:8,自引:0,他引:8  
我国可持续社会养老保险的综合评价指标体系包括四个层次和三级子系统,内容涉及养老保险人数、机构设置、基金管理和代际平衡四个子目标。应用因子分析模糊综合评价方法对我国1990-2001年养老保险建设状况进行评价,本文认为基金管理,行政管理和代际失衡是影响我国可持续养老保险发展的主要因素。  相似文献   
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This paper analyzes the spatial cost efficiency of the Swedish legislation regarding waste disposal handling. We focus on the case of corrugated board and recognize that the different counties in Sweden possess different economic prerequisites in terms of waste paper recovery and utilization potential. We employ data for six corrugated board mills and 20 counties and a non-linear programming model to identify the least cost strategy for reaching the politically specified recycling target of a 65% recovery rate for corrugated board. That is, the total costs of recovering a minimum of 65% in each county are calculated and compared with the case when the country as a whole recovers 65% of all old corrugated board is collected but there exist no uniform target for each county. The conclusion is that from an efficiency point of view the recovery efforts should be concentrated to the highly populated and urbanized counties, and not be uniformly divided throughout the country. In the base case, the results suggest that the cost efficient county-specific recovery rates should range from 51 to 72%.  相似文献   
6.
太湖北部小流域沉积物重金属污染特征与评价   总被引:1,自引:0,他引:1  
孙恬  王延华  叶春  陈西 《中国环境科学》2020,40(5):2196-2203
近几十年来重金属的沉积记录、来源及污染水平受到了广泛关注.为探明太湖北部小流域重金属的污染来源和环境质量状况,本研究分析了柱状沉积物中8种重金属(Mn、Cr、Zn、Cu、As、Pb、Ni和Co)含量.运用主成分分析法判定污染源,富集因子法表征重金属富集特征,通过熵权模糊模型对沉积物中重金属污染状况进行评价.结果显示,所有重金属含量均较高,高低依次为Mn > Cr > Zn > Cu > As > Pb > Ni > Co.其中Mn含量最高,为380.06~767.69μg/g.沉积物重金属污染的主要贡献因子为交通排放、农业污染和煤炭燃烧.As的富集指数最大(2.89~15.61).其中77.59%的沉积层属于显著富集,受人类活动影响最为显著.熵权模糊综合评价结果表明,Cu(0.483)和As(0.352)的权重值最大,是沉积物中的首要污染物,且65.52%的沉积层重金属含量处于中度污染水平.  相似文献   
7.
目的通过地面环境试验研究气动热引起的瞬态高温环境对飞行器结构的影响。方法设计基于石英灯和离心机的瞬态高温-加速度复合试验系统,研究温度和加速度同步控制系统的结构和原理,分析无制冷装置环境下瞬态高温控制的难点,提出基于模糊PI控制器的温度控制策略。结果通过MATLAB仿真验证,设计的模糊PI控制器相比传统的PI控制器能够有效提高温度控制的动态性能与精确性。结论将基于模糊PI控制的瞬态加热控制策略应用于瞬态高温控制是可行、有效的,能为地面气动热模拟环境试验提供技术保障。  相似文献   
8.
本文构建S-T模型,运用集对分析理论(set pair analysis)构建基本模型,采用层次分析法并参考毒性当量因子确定各指标权重,应用三角模糊数(triangular fuzzy number)对差异度系数进行改进,基于加拿大沉积物环境质量标准,对沉积物中多环芳烃进行生态风险分级评价.结果表明,该模型考虑到化合物之间的相互作用因素并做模糊处理,对差异度系数进行改进体现沉积物中多环芳烃生态风险等级标准的模糊性,为持久性有机污染物生态风险分级评价提供了一种简便客观有效的方法.  相似文献   
9.
Air pollution monitoring programs aim to monitor pollutants and their probable adverse effects at various locations over concerned area. Either sensitivity of receptors/location or concentration of pollutants is used for prioritizing the monitoring locations. The exposure-based approach prioritizes the monitoring locations based on population density and/or location sensitivity. The hazard-based approach prioritizes the monitoring locations using intensity (concentrations) of air pollutants at various locations. Exposure and hazard-based approaches focus on frequency (probability of occurrence) and potential hazard (consequence of damage), respectively. Adverse effects should be measured only if receptors are exposed to these air pollutants. The existing methods of monitoring location prioritization do not consider both factors (hazard and exposure) at a time. Towards this, a risk-based approach has been proposed which combines both factors: exposure frequency (probability of occurrence/exposure) and potential hazard (consequence).This paper discusses the use of fuzzy synthetic evaluation technique in risk computation and prioritization of air pollution monitoring locations. To demonstrate the application, common air pollutants like CO, NOx, PM10 and SOx are used as hazard parameters. Fuzzy evaluation matrices for hazard parameters are established for different locations in the area. Similarly, fuzzy evaluation matrices for exposure parameters: population density, location and population sensitivity are also developed. Subsequently, fuzzy risk is determined at these locations using fuzzy compositional rules. Finally, these locations are prioritized based on defuzzified risk (crisp value of risk, defined as risk score) and the five most important monitoring locations are identified (out of 35 potential locations). These locations differ from the existing monitoring locations.  相似文献   
10.
An optimization model for land reservation was developed that explicitly selects parcels in the most compact or contiguous manner possible while meeting habitat requirements and a budget limitation. The model was used to compare the effects of an existing reserve network on future parcel spatial locations and total cost. Using habitat and land value data from Josephine County, Oregon, it was found that a system of existing reserves created by various policies and overseen by different agencies can decrease future reserve compactness and contiguity, and increase total cost. This work suggests that coordinated planning can result in more efficient conservation efforts for less cost.  相似文献   
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