Ranking environmental projects model based on multicriteria decision-making and the weight sensitivity analysis

With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects （alternatives） for obtaining the best environmental quality and economic benefits is an important problem for the decision makers. The purpose of this paper is to develop a decision-making model to rank a finite number of alternatives with several and sometimes conflicting criteria. A model for ranking the projects of municipal sewage treatment plants is proposed by using exports＇ information and the data of the real projects. And, the ranking result is given based on the PROMETHEE method. Furthermore, by means of the concept of the weight stability intervals （WSI）, the sensitivity of the ranking results to the size of criteria values and the change of weights value of criteria are discussed. The result shows that some criteria, such as “proportion of benefit to project cost”, will influence the ranking result of alternatives very strong while others not. The influence are not only from the value of criterion but also from the changing the weight of criterion. So, some criteria such as “proportion of benefit to project cost” are key critera for ranking the projects. Decision makers must be cautious to them.

Weight Determining of Factors Influencing Grain Output Based on Entropy Weight Method

This article selects 8 main factors(the number of rural employees,total power of agricultural machinery,effective irrigation area of crops,growing area of grain crops,fertilizer consumption,electricity consumption in rural areas,area affected and area covered) as the factors influencing grain output,and offers the method of determining weight of factors influencing grain output using entropy weight method.According to the relevant data in the period 1985-2005,we analyze the weight of factors influencing grain output in China by example.The results show that the electricity consumption in rural areas has the greatest impact on grain output,followed by total power of agricultural machinery,fertilizer consumption and area covered.To increase grain output,we must enhance the degree of mechanization,free people from the former process of direct cultivation,strengthen water conservancy construction,and do a good job in disaster prevention and mitigation.

Benefit allocation model of distributed photovoltaic power generation vehicle shed and energy storage charging pile based on integrated weighting-Shapley method

In this study,to develop a benefit-allocation model,in-depth analysis of a distributed photovoltaic-powergeneration carport and energy-storage charging-pile project was performed;the model was developed using Shapley integrated-empowerment benefit-distribution method.First,through literature survey and expert interview to identify the risk factors at various stages of the project,a dynamic risk-factor indicator system is developed.Second,to obtain a more meaningful risk-calculation result,the subjective and objective weights are combined,the weights of the risk factors at each stage are determined by the expert scoring method and entropy weight method,and the interest distribution model based on multi-dimensional risk factors is established.Finally,an example is used to verify the rationality of the method for the benefit distribution of the charging-pile project.The results of the example indicate that the limitations of the Shapley method can be reasonably avoided,and the applicability of the model for the benefit distribution of the charging-pile project is verified.

SEMI-WEIGHT FUNCTION METHOD ON COMPUTATION OF STRESS INTENSITY FACTORS IN DISSIMILAR MATERIALS

Semi_weight function method is developed to solve the plane problem of two bonded dissimilar materials containing a crack along the bond. From equilibrium equation, stress and strain relationship, conditions of continuity across interface and free crack surface, the stress and displacement fields were obtained. The eigenvalue of these fields is lambda. Semi_weight functions were obtained as virtual displacement and stress fields with eigenvalue?_lambda. Integral expression of fracture parameters, K Ⅰ and K Ⅱ, were obtained from reciprocal work theorem with semi_weight functions and approximate displacement and stress values on any integral path around crack tip. The calculation results of applications show that the semi_weight function method is a simple, convenient and high precision calculation method.

A WEIGHTED RESIDUAL METHOD FOR ELASTIC-PLASTIC ANALYSIS NEAR A CRACK TIP AND THE CALCULATION OF THE PLASTIC STRESS INTENSITY FACTORS

In this paper, a weighted residual method for the elastic-plastic analysis near a crack tip is systematically given by taking the model of power-law hardening under plane strain condition as a sample. The elastic-plastic solutions of the crack lip field and an approach based on the superposition of the nonlinear finite element method on the complete solution in the whole crack body field, to calculate the plastic stress intensity factors, are also developed. Therefore, a complete analvsis based on the calculation both for the crack tip field and for the whole crack body field is provided.

Weight Function Method for Stress Intensity Factor of Internal Surface Semi-elliptical Crack in Elliptical Holes

The hatches for inspecting are usually designed with elliptical holes in airplane structures, so computation of the stress intensity factor of three dimensional crack at elliptical holes is pivotal for damage tolerance analysis of these structures. In this paper, weight function is derived for a two dimensional through cracks at elliptical holes by applying a compounding method. Stress intensity factor formulas for an internal surface semi-elliptical crack in elliptical holes are obtained wing the three dimensional weight function method. Stress intensity factors for an internal surface semi-elliptical crack in elliptical holes under remote tension are computed. At the same time, research on how radius of curvature for elliptical holes affect stress intensity factors was conducted. Stress intensity factors decrease when radius of curvature increases. Some results and conclusions which are of practical value are given.

Tide forecasting method based on dynamic weight distribution for operational evaluation

Through analysis of operational evaluation factors for tide forecasting, the relationship between the evaluation factors and the weights of forecasters was examined. A tide forecasting method based on dynamic weight distribution for operational evaluation was developed, and multiple-forecaster synchronous forecasting was realized while avoiding the instability cased by only one forecaster. Weights were distributed to the forecasters according to each one＇s forecast precision. An evaluation criterion for the professional level of the forecasters was also built. The eligibility rates of forecast results demonstrate the skill of the forecasters and the stability of their forecasts. With the developed tide forecasting method, the precision and reasonableness of tide forecasting are improved. The application of the present method to tide forecasting at the Huangpu Park tidal station demonstrates the validity of the method.

基于DEMATEL-ISM方法的水电站机组检修作业安全事故致因链分析

针对水电站机组检修作业种类和危险因素多、安全事故频发等问题,通过文献挖掘与专家访谈方式,对水电站机组检修作业安全影响因素类别进行了划分。基于DEMATEL-ISM方法,构建了安全事故致因多层次递阶ISM模型来确定事故致因因素层级,通过剖析事故致因因素的中心度和权重,挖掘关键致因因素和推求事故致因链的路径权重,厘定关键致因链。采用该模型对某水电站致因链进行了分析,结果表明,安全检查不到位为关键致因因素,“安全检查不到位→违规作业→设备的问题→粉尘、油漆等有害物质”为关键致因链。

区域创新发展能力评价与空间差异测度

区域创新发展能力是区域经济在发展过程中获取竞争优势的重要影响因素,文章从区域创新发展规模、区域创新发展条件、区域创新发展活力、区域创新发展环境四个子系统筛选出20个可观测指标构建区域创新发展能力评价指标体系,应用面板数据熵权法对我国31个省份2014—2019年创新发展能力进行综合评价,利用泰尔指数和莫兰指数对创新发展能力空间差异特征进行分析,并为区域创新发展能力实现协同发展提供参考。

阜阳市幸福河湖评价及障碍因子识别

从水资源供给、水资源利用、水环境治理、水生态环境、水经济发展5个方面出发,选取15个指标建立了幸福河湖评价指标体系。基于熵权法和TOPSIS模型对阜阳市2012—2021年的幸福河湖情况进行了综合评价,采用障碍度模型识别了影响阜阳市幸福河湖的障碍因子。结果表明:阜阳市的幸福河湖建设情况在2012—2021年呈逐步增长趋势,影响幸福河湖的主要因素是水资源量、水资源利用及水生态环境情况。据此,结合阜阳市的水资源对经济发展的承载能力等方面,提出了优化阜阳市幸福河湖建设的建议。

基于Rasch模型的船舶舾装效率影响要素分析

针对现有提高舾装效率的研究局限于某一环节,缺乏全面系统性分析,难以客观准确评价各因素影响程度的问题,基于实地考察、专家访谈、问卷调查等方法,综合考虑舾装作业离散型特征,从策划和实施2个阶段分析涉及设计、设备、计划以及人机料法环等8个方面的38个影响舾装效率的因素,采用Vague集-熵权法进行主客观评估,筛选出28个关键因素,并采用Rasch模型方法对影响舾装效率的多重要素进行影响程度定量分析。研究发现:策划阶段对舾装效率的影响程度较大,其中因不可控要素供应链受阻是影响最大的要素。研究表明企业应对策划阶段重点改进;实施阶段对舾装效率影响较小,企业无需投入过多资源改进。

湖北省城市雨涝灾害韧性的时空演变及障碍因子

为探讨湖北省城市雨涝灾害韧性的时空演变及障碍因子,构建包含经济、社会、基础设施和生态环境4维度韧性评价指标体系,采用组合权重TOPSIS法测度韧性水平,结合GIS空间分析方法探究其时空演变特征,运用障碍度模型对评价结果进行障碍因子诊断。研究结果表明:湖北省城市雨涝灾害韧性整体呈上升趋势,各城市间韧性指数差异程度有所减小,韧性水平趋向均衡化发展;湖北省城市雨涝灾害韧性呈现“东西强、中间弱”空间分布格局,全局不存在显著的空间集聚性;单位面积泵站数量、万人在校大学生数、公共安全财政投入比、排水管道密度和人均GDP是制约湖北省城市雨涝灾害韧性的5大主要障碍因子。研究结果可为湖北省制定区域洪涝灾害管理政策及韧性城市规划提供参考。

黄河流域发展质量综合评估及其主要障碍因子识别

为了给高质量建设现代化黄河流域提供数据佐证和学理支撑,设置包括2个子系统(生态保护和高质量发展)共7个维度(资源利用、环境治理、环境质量、创新发展、协调发展、开放发展、共享发展)的黄河流域发展质量评价指标体系,采用反熵值法计算指标权重及各子系统综合指数,采用生态位适宜度模型评估2011—2020年黄河流域发展质量,采用修正的耦合协调度模型和相对发展度模型分析黄河流域生态保护与高质量发展耦合协调状况,采用障碍度模型识别黄河流域发展质量的主要障碍因子。结果表明:1)2011—2020年黄河流域发展质量整体上稳步上升,但研究时段末仍相对较低,还有较大提升空间;2)从黄河流域发展质量各维度生态位适宜度看,环境治理、资源利用达到中等适宜,协调发展和环境质量为低度适宜,共享发展属于低度不适宜,创新发展和开放发展属于中等不适宜;3)黄河流域生态保护与高质量发展耦合协调等级已由勉强协调上升到初级协调,二者一直处于生态保护领先的失衡或严重失衡状态;4)在发展质量的7个维度中,共享发展处于核心地位,开放发展、创新发展、协调发展是高质量发展子系统的短板,资源利用、环境质量是生态保护子系统的弱项。在评价指标中,技术市场成交额占GDP比重、人均进出口值、外资开放度、自然保护区面积占总面积比例、农业产业劳动生产率、城市土地节约利用水平、工业固体废弃物综合利用率是黄河流域发展质量的主要障碍因子。

基于DEMATEL和熵权法的生鲜食品网购决策影响因素研究

随着电子商务生活化的普及,生鲜行业也日趋电商化。生鲜电商企业面对日益增长的市场规模的同时也面临着日益激烈的行业竞争。生鲜电商企业通过识别客户购买决策的影响因素并进行重要性排序,可以有的放矢地改进工作,进而可以提高消费者完成购买的转化率、促进商家的商品销量。通过构建影响客户网购生鲜食品决策的指标体系,采用DEMATEL方法确定各影响要素的地位及其因果关系。为了克服DEMATEL法专家评价主观的局限性,使用客观赋权的熵权法计算出熵权值,利用乘法合成法进行组合赋权,通过组合权重排序分析得出电商平台信誉度、电商平台知名度、售后服务完善度、电商平台管理规范度、生鲜食品品质、生鲜食品品牌知名度、配送的保鲜度、配送快捷性是影响消费者网购生鲜食品决策的重要因素。因此,生鲜电商商家可以从选择优质的第三方平台、优化店铺服务流程、建立生鲜食品质量保证体系等方面加以改进,进一步提升网络消费者生鲜食品的购买转化。

基于AHP-DEMATEL模型的装配式钢结构建筑施工安全风险分析

针对我国装配式钢结构建筑施工过程中存在的安全风险问题,文章从人为、管理、技术、环境四个方面构建了风险影响因素指标体系,通过运用AHP-DEMATEL法计算出组合权重,并对各风险因素的权重进行排序,得到影响施工安全的关键因素并提出针对性建议。研究结果表明,现场管理人员能力、钢构件的吊装施工、钢结构施工图纸设计以及钢构件的拼装焊接等是影响装配式钢结构建筑施工安全的关键因素。

生态脆弱性与城镇化水平时空耦合及其交互影响因素——以湖南省为例

协调生态建设与城镇化是实现区域可持续发展的保证,对科学引导城镇化并实现高质量发展具有重大意义。为探究我国中部地区生态环境脆弱程度与城镇化水平整体进程之间的关系,以湖南省为例,各县区为评价单元,基于生态敏感性-生态恢复力-生态压力度模型构建生态脆弱性评价指标体系,通过人口-经济-社会-空间模型构建城镇化水平评价指标体系,通过耦合协调度模型多维度测算湖南省2000—2020年生态脆弱性和城镇化水平的空间耦合关系,并运用双变量空间自相关、时空地理加权回归模型探究其交互影响效应。结果表明:(1)研究期间,湖南省生态脆弱程度呈先加重后减轻的趋势,以长株潭为核心重度脆弱区,向南北方向扩散,形成南北地区脆弱程度高、中西部生态脆弱程度低的格局;(2)城镇化水平差异较大,总体呈现上升的趋势,高水平城镇化区域从2000年以各地级市行政中心向外发散的散点式布局,到2020形成以长株潭为核心高值区,东部整体较高,西部偏低的空间分布格局;(3)湖南省严重失调区县明显减少,基本协调区县明显增加的趋势,且城镇化水平是制约湖南省生态环境与城镇化均衡高质量发展的主要因素。(4)交互作用结果表明,城镇化发展导致地区生态脆弱程度加深,而地区生态状况又反向制约城镇化水平可持续、高质量发展。研究表明,湖南省需着力推进生态环境建设和城镇化水平的健康发展,缓解城镇化发展和生态环境的矛盾,以期实现区域城镇化与生态协同发展。

城市地面塌陷灾害风险评估研究

随着城市化进程不断加快,城市地下空间安全问题引起广泛关注。本文以影响地下空间安全的典型灾害-地面塌陷为例,开展可能性风险评估研究,为降低地面塌陷灾害损失提供理论支撑。城市地面塌陷成因复杂,为了保证评价过程和结果的客观全面,通过调研对塌陷引发因素进行了总结,从管道因素、病害体因素、环境因素三个方面建立风险发生可能性评价指标体系,并使用AHP-熵权法-灰色关联法组合评价,建立地面塌陷风险评价模型。将该模型应用于郑州市典型地下空洞工程案例进行评估分析,结果表明:地面塌陷风险评价结果与实测结果相符,证明了评估模型的科学性,同时为城市地面塌陷预防提供了决策参考。

城市景观水体水质时空分布特征及其评价方法适用性研究

为探究城市景观湖泊水质特征及其水质评价的适用性方法,以兴庆湖为研究对象,选取5个采样点,根据2018年1月至2020年9月水体逐月pH值及TP、NH_(3)-N、DO、COD浓度监测值,采用单因子评价法、综合水质指数评估法、水质健康综合评估法和熵权-TOPSIS法对兴庆湖水质进行评价。结果表明:兴庆湖水质指标存在时空分布差异,水体进入兴庆湖后,除氨氮外,其他水质指标值增大;pH值春夏两季高于秋冬两季,TP质量浓度夏秋两季高于春冬两季,COD、NH_(3)-N质量浓度秋冬季高于春夏季;4种水质评价方法对兴庆湖水质评价结果有差异,经综合比较分析,熵权-TOPSIS法不受指标数量、数据分布等的限制,减少了主观因素的影响,能准确反映水体水质情况。

考虑冻融侵蚀型物源的不同流域单元泥石流易发性评价——以藏东贡觉地区为例

在全球气候变暖背景下,高原山区潜在泥石流暴发的概率将增大,定量评估泥石流易发性是区域减灾防灾的先行手段。基于现场调查和研究结果,首次计算了藏东贡觉地区的冻融侵蚀强度(DR)。选取物源条件和地形条件,采用加权信息量法评价了藏东贡觉地区泥石流的易发性,以四组流量阈值划分的不同流域单元作为评价单元对比分析了易发性评价结果。结果显示,四组易发性评价结果差异明显,随着流域单元划分数量的降低(流量阈值增大),研究区中风险区面积逐渐增大,高~极高风险区面积先增大后降低。受试者特征曲线(ROC)验证结果表明,使用G2组(流量阈值5000)划分得到的流域单元模型评估效果更好,AUC值为0.895,高易发区、极高易发区面积占全区约34.1%。八个评价因子中,冻融侵蚀强度(DR)、地形特征指数(TCI)和平面曲率(Pl_cv)是泥石流易发程度贡献率较大的三个因子。考虑冻融侵蚀型物源和地形水文因子建立的泥石流易发性评价模型,为冻融侵蚀现象明显的藏东地区泥石流易发性评价提供了新的方法和思路,对指导地方防灾减灾具有重要实践意义。

光热电站太阳能典型气象年的气象要素权重取值分析

影响光热电站(CSP)性能的各气象要素主要有水平面总辐射(GHI)、法向直接辐射(DNI)、温度及风速,各气象要素的权重因子赋值不同会导致典型气象年(TMY)结果的差异。本文以西北某地区多年实测辐射数据以及长系列卫星辐射数据为研究基础数据,分别采用Sandia、SolarGIS及CSWD的分析方法,采用随机赋值法,得出我国西北某地区光热电站典型年太阳能资源分析DNI、GHI、风速、温度的权重取值如下:采用Sandia方法时,分别为0.6、0.2、0.1及0.1;采用SolarGIS方法时,分别为0.7、0.1、0.1及0.1;采用CSWD方法时,分别为0.6、0.1、0.2及0.1。本文的研究结果将为太阳能光热电站的高效利用及推广提供一定的借鉴。