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1.
城市生态安全多层次灰色综合评价   总被引:3,自引:1,他引:2  
从城市生态安全的基本内涵出发,根据压力(pressure)-状态(state)-响应(response)模型,从生态系统压力、生态系统状况、生态系统响应3方面构建一个4层次的城市生态安全评价指标体系,运用灰色系统理论,构建了城市生态安全多层次灰色综合评价模型,并结合实例进行计算。评价结果与实际情况基本相符,表明该模型能有效地利用评价指标的信息,所给出的综合评价值既能用于描述所评价城市的生态安全状况,亦可对不同城市的生态安全状况进行比较,对更加科学合理地评价城市生态安全状况具有参考价值。  相似文献   

2.
基于PSR(压力-状态-响应)模型构建城市生态安全评价指标体系,采用层次分析法确定各指标权重,对2001-2007年北京城市生态安全现状进行评价.结果表明,2001-2007年北京市处于"较不安全"状态,其上要影响因素为较大水资源压力和亟须改善的空气质量.评价结果与实际情况基本相符合,表明本研究建立的城市生态安全评价指标体系和评价方法可行.  相似文献   

3.
老工业城市面临资源过度开采带来的生态环境破坏问题,生态安全评价与预测有助于改善环境质量,提高生态系统稳定性。基于压力-状态-响应(Pressure-State-Response, PSR)模型构建生态安全评价指标体系,综合使用熵权法和层次分析法确定指标权重,运用综合指数模型对宁夏石嘴山市2010—2020年进行生态安全评价,并通过障碍度模型分析限制石嘴山市发展的制约因素,使用灰色预测GM(1, 1)模型对石嘴山市未来几年生态安全状态进行预测。结果显示:石嘴山市生态安全由2010年的“恶劣”逐渐转变为2020年的“临界安全”。目前,制约石嘴山市生态发展的主要因素有工业废气排放总量、一般工业固体废物综合利用率、化肥施用量和能源消耗量。石嘴山市未来几年生态安全状态将继续呈现好转,其状态将由“临界安全”逐渐转换为“较安全”。  相似文献   

4.
为了分析土地利用变化影响下的城市生态安全水平的动态变化,选择中部快速城市化地区的郑州市为研究区域,研究时间为1992—2009年。在分析郑州市主要生态安全问题的基础上,以GIS和RS为平台,基于PSR(压力-状态-响应)模型,选择能够反映郑州市生态安全状况的人文社会环境压力指标、自然生态环境状态指标、人文环境响应指标,拟定了具有区域特色的郑州市生态安全综合评价指标体系;运用生态安全综合评价模型计算了研究区1992年、2001年、2009年的区域生态安全指数,进一步分析了研究区的生态安全状况。结果表明:1)郑州市生态安全总体水平不高,以临界安全等级为主,较安全状态区域所占比重不大;2)从时间动态上看,近17年来郑州市生态安全指数中未发生变化类、增加类、减小类面积所占比例分别为72.72%、12.25%、15.53%,生态安全指数增加类的面积小于减小类的面积,表明郑州市的生态安全整体水平在往不安全的方向发展;3)从空间分布上看,近17年来区域生态安全水平变化的空间差异较为明显,金水区、管城区、中原区、惠济区的周边,以及市区和中牟县北部沿黄滩涂生态安全指数以减小类型为主,而二七区、荥阳市西南部山区及其北部沿黄部分区域生态安全指数以增加类型为主。研究表明,评价模型能够实现像元、区域、整体不同尺度的评价。  相似文献   

5.
以铜川市为例进行城市生态安全评价和指标分析,采用压力-状态-响应模型和层次分析法构建出含有项目、因素、指标的铜川市生态安全评价体系。通过生态不安全指数定量表示城市的生态安全状况,对铜川市2014-2016年的生态安全状况进行了综合评价,并计算分析了各指标对城市总体生态不安全指数的贡献度。结果表明,铜川市的生态安全处于“临界安全”状态,并呈现逐渐向好的发展趋势。人均灌溉农田面积、地表水环境质量、环境空气质量和环保投资占GDP比例对铜川市生态不安全指数贡献度较大,应给予重视。  相似文献   

6.
李德记 《安全》2015,(4):41-45
采用层次分析法确定评价指标因素的相对权重,以灰色关联分析得出参评数据序列与标准数据序列之间的关联度,其中关联度最大值所对应的标准安全等级,即为乳化炸药生产线的安全等级。结果表明,基于灰色关联和层次分析法适用于乳化炸药生产线的安全评价。  相似文献   

7.
针对常州市生态环境现状,利用"压力-状态-响应(P-S-R)"理论,构建基于城市资源环境压力、资源环境状态和人文环境响应3个类别的城市生态安全评价模型,以常州市2000—2007年发展过程中的人口,经济、环境等相关指标建立的城市生态安全评价体系进行评价,结果表明:常州市的城市生态安全总体水平在中等偏下,多数城市生态指标处于较低水平,影响常州城市生态安全整体水平的提高。利用P-S-R模型对于常州市城市生态建设和城市发展规划具有一定的参考价值。  相似文献   

8.
基于DPSIR模型的区域水安全评价研究   总被引:1,自引:1,他引:0  
为了对区域水安全状况进行有效评价,采用"驱动力-压力-状态-影响-响应"模型,选取27项指标,构建区域水安全评价指标体系,通过层次分析法与熵值法确定评价指标在满足主客观条件下的组合权重,运用综合指数法模型,对2004-2008年广东省水安全状况进行了动态评价.结果表明,广东省水安全水平逐年提高,但总体水平不高,处于警戒状态,存在较大的不安全隐患.虽然响应指标在水安全方面起重要的作用,使系统存在的状态都处于上升的趋势,但系统驱动力、压力强度仍然较大,说明广东省水安全水平的提高很大程度上是依赖对环境的治理和投入.  相似文献   

9.
为保证大型泵站的安全运行,构建了一套完整的大型泵站运行安全综合评价体系,确定大型泵站运行的安全等级,明确安全管理要点,指导开展检修、维修等工作。首先,基于事故致因理论,结合大型泵站运行特点从“人员-设备-环境-管理”方面识别出20个评价指标;然后,运用决策与实验室法和网络层次分析法确定各评价指标权重;最后,运用灰色关联度分析法构建大型泵站运行安全综合评价体系,并以南水北调中线某大型泵站为例进行了实例计算。结果表明:大型泵站运行安全管理工作的重点为金结机电运行情况、金结机电缺陷情况、维保实施情况等;南水北调中线某大型泵站运行安全等级为1级,处于安全状态。  相似文献   

10.
湿地是世界上具有独特结构与功能的生态系统,黑河流域湿地生态系统健康与安全对我国西北干旱区生态网络建设具有重要意义。选取黑河中游典型的城市湿地——张掖北郊湿地为研究区,基于"压力—状态—响应"框架模型,构建湿地生态安全评价指标体系,并运用层次分析法确定各指标权重,以综合指数法对湿地生态安全性进行了综合评价。研究结果表明:张掖北郊湿地生态安全综合指数为0.580,处于中度安全状态;生态系统的主要服务功能尚能发挥,但个别生态压力已超出生态系统的承载能力,显示出湿地的保护和管理存在不足。  相似文献   

11.
在分析500kV变电站主变压器消防系统的现状,比较3类消防系统优缺点的基础上,详细论述了主变排油注氮装置的结构组成、工作原理、参数计算、控制系统设计以及需要注意的事项等,为下一步排油注氮装置的推广应用打下基础.  相似文献   

12.
为克服传统危险与可操作性(HAZOP)定性分析方法在复杂操作、间歇作业等过程中使用的局限性,提出在传统HAZOP定性分析方法的基础上结合What-if(故障假设)方法,对人的不安全行为和操作规程不完备所导致的风险后果分析作出补充。详细说明其技术原理、工作流程等使用细节,系统阐述该方法与传统HAZOP定性分析方法的区别,并在某延迟焦化装置的除焦操作的风险分析中应用。经分析,识别出在“给水-泡焦”节点,有“操作规程错误”场景2项,“操作规程不具体”场景1项,不存在“操作人员未按操作规程执行”场景。研究结果表明:本文方法有效且具有较好效果,可以广泛应用于操作规程/作业指导书审查、作业过程隐患排查等方面,帮助企业开展操作层面的风险识别与管理,提升企业的生产安全水平。  相似文献   

13.
为了研究原位煤体渗透性的各向异性特征,以山西潞安常村矿3号煤层圆柱试样为对象,利用TCQT-Ⅲ型低渗煤层气相驱替增产试验装置,对煤样进行加载,并以氮气注入压力2.0 MPa的条件下,分析垂直层理和平行层理2个方向的煤体变形和渗透率变化特征。实验结果表明:煤样在加载过程中,平行和垂直层理煤样渗透率均随着有效应力的增大而减小,平行层理方向的渗透率始终大于垂直层理方向,应力加载初期渗透率急剧下降,最后逐渐趋于平缓;径向应变的增加量与渗透率呈正相关性,且平行层理相关性大于垂直层理;沿平行层理方向的裂隙度大于沿垂直层理方向,沿垂直层理方向的应变量大于沿平行层理方向;应变增加量均随有效应力的增加而逐渐减小。研究结果可为煤层井网布置及优化提供参考。  相似文献   

14.
Introduction: Pedestrian fatalities in the United States increased 45.5% between 2009 and 2017. More than 85% of those additional pedestrian fatalities occurred at night. Method: We examine Fatality Analysis Reporting System (FARS) data for fatal pedestrian crashes that occurred in the dark between 2002 and 2017. Within-variable and before/after examinations of crashes in terms of infrastructure, user, vehicle, and situational characteristics are performed with one-way analysis of variance (ANOVA) and two-sample t-tests. We model changes in crash characteristic proportions between 2002–2009 and 2010–2017 using linear regressions and test for autocorrelation with Breusch-Godfrey tests. Results: The increase in fatal nighttime pedestrian crashes is most strongly correlated with infrastructure factors: non-intersection unmarked locations (saw 80.8% of additional fatalities); 40–45 mph roads (54.6%); five-lane roads (40.7%); urban (99.7%); and arterials (81.1%). In addition, SUVs were involved in 39.7% of additional fatalities, overrepresenting their share of the fleet. Increased pedestrian alcohol and drug involvement warrant further investigation. The age of pedestrians killed increased more (18.1%) than the national average (3.2%). Conclusions: By identifying factors related to the increase in nighttime pedestrian fatalities, this work constitutes a vital first step in making our streets safer for pedestrians. Practical Applications: More research is needed to understand the efficacy of different solutions, but this paper provides guidance for such future research. Engineering solutions such as road diets or traffic calming may be used to improve identified infrastructure issues by reducing vehicle speeds and road widths. Rethinking vehicle design, especially high front profiles, may improve vehicle issues. However, the problems giving rise to these pedestrian fatalities are likely a result of not only engineering issues but also interrelated social and political factors. Solutions may be correspondingly comprehensive, employing non-linear, systems-based approaches such as Safe Systems.  相似文献   

15.
Footedness is a personal quality like handedness. Footedness may be associated with moving ability during mounting, dismounting, and jumping movements. Occupational accidents have occurred during movement at different working levels, during the use of access and exit systems, and during the mounting of vehicles. Aging can also affect accident risk and body laterality. For example, falling accidents on stairs are common among the elderly. One reason for accidents may be that the structure of the access system or stair system is unsuitable for individual moving patterns depending partly on body laterality. Footedness and the way the feet are used may be contradictory to the demands of the moving situation, especially during uncommon or rapid situations. This contradiction may trigger disturbance during moving. The aims of this pilot study were (a) to review the literature briefly and (b) to describe the use of the dominant and nondominant foot by farmers and the elderly when mounting a tractor and stairs, respectively. The study also gives ideas for future studies based on both (a) and (b).  相似文献   

16.
为了减少滑坡造成的损失,提高滑坡预测的准确性,通过搭建灾害模拟平台获得滑坡的实验数据,在获得多组模拟实验数据后,分析各变量的特性。首先,通过层次分析(Analytic Hierarchy Process,AHP)算法,对滑坡进行危险度划分;然后,通过支持向量机(Support Vector Machine,SVM)建立模型,遗传算法(Genetic Algorithm,GA)再优化SVM参数,提出1种层次分析法与GA-SVM相耦合的模型。研究结果表明:AHP方法划分后的数据,通过GA与SVM结合建立的模型精度较好,实验预测结果与实际结果较为吻合,与单一SVM相比,精度更高,结果更好,更加适用于多变量的复杂非线性滑坡预警。  相似文献   

17.
Leadership theories have shifted over the last few decades from a focus on managerial functions and economic leader–follower exchanges toward greater focus on the interpersonal dynamics occurring within the leadership process. Theories such as transformational, ethical, authentic, and other “newer genre” theories were created to address neglected topics such as leader vision and inspirational messages, transparency, emotional effects, morality, individualized attention, and intellectual stimulation. Critiques of these theories, however, have been raised. In this paper, we address five of those critiques and argue for the validity and practical effectiveness of the new genre theories. Further, we describe how newer genre leadership research should be viewed as a performative epistemology, entailing a process of co‐creation involving scholars and practitioners. Finally, from this view, we provide general ideas for leader development. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

18.
Occupational Safety and Health in Finland   总被引:1,自引:0,他引:1  
In Finland, occupational safety is the responsibility of the employer, while the occupational safety and health laws are enforced by the Labour Inspection Service, an organization of the state. The Labour Inspection is divided in 11 administrative districts, and it employs 360 professionals. They are mandated to carry out site visits without prearranged appointments to inspect safe work situations, working hours, construction safety, or any aspect of accident risks. The inspectors are also mandated to verify the existence of sufficient occupational health services as prescribed by the Occupational Health Services Act for all employees. The occupational health services are typically provided by enterprise-owned medical departments, by mutually owned health care centers, by private practitioners, or by municipal health care centers. The latter are required by law to provide all services as prescribed by the legislation to anyone who comes to the facility. This situation is prevalent in the countryside, where there are very few private caregiving centers. Declaring occupational accidents and disease cases is mandatory, and the Inspection districts examine all accidents to establish causes and consequences, and to initiate prosecution in case of criminal negligence. Labour Inspection Districts are also notified of the new occupational disease cases as they are declared to insurance companies. Insurance for occupational disease, accidents, and death is an obligation of the employer, although they can choose the insurance company. The medical confidentiality between the workers and their occupational health care providers is very strict. Official statistics are maintained by the state Statistics Finland organization, and they may be used, for example, for research purposes by scientific institutes like the Finnish Institute of Occupational Health. Construction industry accounts for 25% of all fatal accidents (120 cases per 1 million working hours), followed by mechanical, wood, metal, machinery, and pulp and paper industry (10% each of fatal accidents) with rates ranging from 100–160 cases per 1 million working hours. There are some 5,000 occupational disease cases per year (rate 22/10,000 employed). The major disease categories include repetitive strain injuries (1,300 cases), respiratory allergies (600 cases), occupational skin diseases (1,000 cases), and 900 cases of noise-caused hearing loss. In 1998, 589 cases of asbestos-related diseases were reported.  相似文献   

19.
森林地表火蔓延模拟方法及其计算机实现   总被引:6,自引:1,他引:5  
杜飞  候遵泽  刘家琦 《火灾科学》2001,10(4):204-208
进行了森林火蔓延的研究,对传统的经验公式和模型进行改进,明显发现改进的模型有更好的结果,用计算机巧妙准确地实现了模拟模型,在风力不是特别大,地形变化不是特别剧烈时,该模型有较高精度;并结合火蔓延的主要因素(气象因子、气候、地形等),进行系统分析,写出算地,编制实现地表火蔓延的预测预报计算机系统软件。这对于有效的组织扑救、减少火灾损失、计算森林火灾的损失评估有重要意义。  相似文献   

20.
公路隧道火灾逃生疏散研究   总被引:2,自引:1,他引:1  
以苍岭隧道为背景,首先采用经验计算理论和计算软件building EXODUS相结合的方式,从被困人员的安全疏散时间、高温烟气的影响、隧道横通道的利用率以及人员的疏散行为特性进行了研究。结果表明:中小规模火灾情况下的安全疏散时间控制在8 min之内,高温烟气影响不大,但横通道的利用率不平均,且人员疏散路线相对集中。然后对存在的逃生疏散问题提出针对性建议以及其他相关建议,旨在为更大程度降低事故的严重性和经济财产损失。  相似文献   

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