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71.
Decisions on soil remediation are one of the most difficult management issues of municipal and state agencies. The assessment of contamination is uncertain, the costs of remediation are high, and the impacts on the environment are multiple. This paper presents a general, transparent, and consistent method for decision making among the remediation alternatives. Soil washing, phytoremediation, and no remediation are exemplarily considered. Multi-criteria utility functions including (a) the cost of remediation (b) the impact on human health and agricultural productivity, and (c) the economic gain after remediation are constructed using probability density functions representing contamination for all site coordinates. Herewith, the probability of different types of (i) correct decisions such as a hit or a true rejection and (ii) erroneous decisions such as a false alarm or miss are examined. The decision theoretic model is applied to a case study on heavy metal contaminated soil. This case study reveals the non-linear structure of multi-criteria-decision making. The case study shows that the geostatistical uncertainties of the log-normal distributed soil contamination must be taken into account: When uncertainties are not considered and the utilities are assessed according to the estimated value for a spatial unit, only few (N=26) spatial units result where the utility score of the alternative soil washing are higher than the utility score to the no remediation alternative. However, when taking into account geostatistical uncertainties of the log-normal soil distribution this number is about ten times greater (N=237). Furthermore, the use of 'maximizing expected utility' as decision rule is critical in that it may lead to a high probability of misses.  相似文献   
72.
本文引入资源和环境因素,以城镇化综合指数为期望产出,运用SBM方向性距离函数测算了2010—2020年长江经济带112个地级市(州)的绿色城镇化效率,并采用空间面板模型和地理探测器对绿色城镇化效率的影响因素进行实证分析。结果表明:长江经济带绿色城镇化效率整体水平不高,下游地区绿色城镇化效率高于上游和中游地区,资源消耗和环境污染是效率损失的主要来源;绿色城镇化效率表现出较为明显的热点—次热点—次冷点—冷点自东向西的带状分布格局,存在显著的空间正相关性。政府财政支出对绿色城镇化效率产生负向影响,外商直接投资和产业结构对提升绿色城镇化效率有显著的促进作用,且三者的影响具有地区差异性;市场力因素有利于绿色城镇化效率的提高。邻近城市间绿色城镇化效率的空间溢出效应明显,且空间溢出效应是长江经济带绿色城镇化效率空间差异的最主要因素,各因素的影响具有协同增强的作用。  相似文献   
73.
Carbonnier G 《Disasters》2006,30(4):402-416
The tendency today to privatise many activities hitherto considered the exclusive preserve of the state has given rise to sharp debate. The specific nature of humanitarian emergencies elucidates in particularly stark contrast some of the main challenges connected to the privatisation and outsourcing of essential public services, such as the provision of drinking water and health care. Privatising the realms of defence and security, which are at the very core of state prerogative, raises several legal and humanitarian concerns. This article focuses on the roles and responsibilities of the various parties involved in armed conflicts, especially those of private companies engaged in security, intelligence and interrogation work, and in the provision of water supply and health services. It highlights the need for humanitarian and development actors to grasp better the potential risks and opportunities related to privatisation and outsourcing with a view to supplying effective protection and assistance to communities affected by war.  相似文献   
74.
主体功能区划通过主体功能划分的方式将开发和保护结合,自然资源开发利用复杂化过程中资源利用与目标实现之间亟需实现基本的定量核算关系。本文从自然资源可持续利用角度,试图探讨建立初步的主体功能核算关系,通过核算框架进行生产、生活、生态主体功能概算与比较。以京津冀主体功能区与水资源为例,对所设立的核算关系进行了验证与应用,并构造绝对与相对量指标量化京津冀主体功能量、功能水资源投入量与效率,进行了异空间尺度与异质性功能的比较,为以主体功能实现最大化为目标的资源优化配置提供量化工具。结果显示:①利用生态服务价值测算的当量因子法与水足迹测算的投入产出法,刻画了水资源对于地区主体功能的支撑作用。②利用功能总量与单位功能水资源投入量指标完成了异质性功能在异质性空间上规模、结构、相应水资源效率的比较。基于算例结果得到以下结论:①本文构建的自然资源-主体功能核算关系框架能够有效衔接主体功能规划,定量核算能有效反映与评价资源对区域功能目标、经济开发活动的支撑作用。②区域资源配置存在相对功能实现的效率差异,可根据资源投入与功能产出之间的关系引导实现功能最大化目标的资源配置。合理、有效的量化手段能够推进主体功能制度的落实,也有助于当前中国空间规划体系编制与落实的实际指导效果。  相似文献   
75.
With several industrial applications of fluidized bed technology recently commercialized worldwide, it becomes essential to develop safe operation methods for fluidized bed reaction systems (FBRSs) to prevent any influence on their process values, which lead to accidents. To preventing any disaster or malfunction in an FBRS, an emergency shutdown system (ESD) is initiated, closing the reaction system in case of any abnormality by effectively isolating the flammable gas. However, an ESD is also prone to the “inactivation problem,” in which in the case of failure it initiates the emergency shutdown, even when the operating conditions of the reaction system are abnormal. It is also vulnerable to a “malfunction problem,” where the emergency shutdown is performed even when the operating conditions of the reaction system are normal. In this study, these problems were solved by investigating a reaction system through the monitoring of appropriate parameters and setting up of trigger levels, which reflect the uniqueness of an FBRS using an ESD. The parameters were identified by analyzing the scenario leading to an accident. The trigger levels were determined as the points at which the loss is smaller in the presence of an ESD, as compared to the value of the loss function in the presence or absence of an ESD. Furthermore, the ESD design model was applied as a case study in the ammoxidation process of propylene. The results showed that an ESD can prevent an approximately 8 billion yen of loss due to accidents in plant operations, against an investment of 200 million yen.  相似文献   
76.
Abstract

A sudden increase in serum creatinine after paraquat intoxication has been reported in several clinical studies. However, this dramatic change of creatinine may be possibly due to an interconversion of creatine-creatinine in relation to paraquat toxicity. In order to investigate the creatine-creatinine relationship, a liquid chromatography tandem mass spectrometry in combination with electrospray ionization was developed and validated for simultaneous determination of creatine and creatinine in the serum. The chromatographic separation was achieved on a Gemini® C6-Phenyl column with a gradient elution consisting of 0.1% formic acid in ultrapure water and methanol as the mobile phase. The method yielded suitable levels of specificity and selectivity, and calibration curves of creatine and creatinine in serum were linear over the concentration range of 0.5–200?µg mL?1. The limit of quantification of both compounds was 0.5?µg mL?1, and the method was accurate within the recovery range of 96.23–102.75%, indicating the robustness of the method. The method was successfully applied to toxicological samples from paraquat-intoxicated patients, and the concentrations of creatine and creatinine were quantified. High creatine concentrations in serum samples were observed which may lead to high serum creatinine despite normal kidney function as creatine is converted to creatinine in proportion to its concentration.  相似文献   
77.
Objective: The objective of this article was the construction of injury risk functions (IRFs) for front row occupants in oblique frontal crashes and a comparison to IRF of nonoblique frontal crashes from the same data set.

Method: Crashes of modern vehicles from GIDAS (German In-Depth Accident Study) were used as the basis for the construction of a logistic injury risk model. Static deformation, measured via displaced voxels on the postcrash vehicles, was used to calculate the energy dissipated in the crash. This measure of accident severity was termed objective equivalent speed (oEES) because it does not depend on the accident reconstruction and thus eliminates reconstruction biases like impact direction and vehicle model year. Imputation from property damage cases was used to describe underrepresented low-severity crashes―a known shortcoming of GIDAS. Binary logistic regression was used to relate the stimuli (oEES) to the binary outcome variable (injured or not injured).

Results: IRFs for the oblique frontal impact and nonoblique frontal impact were computed for the Maximum Abbreviated Injury Scale (MAIS) 2+ and 3+ levels for adults (18–64 years). For a given stimulus, the probability of injury for a belted driver was higher in oblique crashes than in nonoblique frontal crashes. For the 25% injury risk at MAIS 2+ level, the corresponding stimulus for oblique crashes was 40 km/h but it was 64 km/h for nonoblique frontal crashes.

Conclusions: The risk of obtaining MAIS 2+ injuries is significantly higher in oblique crashes than in nonoblique crashes. In the real world, most MAIS 2+ injuries occur in an oEES range from 30 to 60 km/h.  相似文献   

78.
为促进安全管理,提高效率与效果,对基于情感思维的安全管理进行研究,将情感思维融于安全管理,基于情感思维的定义、内涵及功能,具体分析安全管理中情感思维的功能及其功能综合作用,建立安全管理中情感思维功能作用理论模型;根据该理论模型分析情感思维驱动力及强化作用及其对安全目标实现的影响;建立基于情感思维的安全管理设计模式,最后提出优化安全管理的措施与方法,以促进安全管理的实施。研究表明:基于情感思维的安全管理研究,能较好地体现安全管理人本原理,发挥情感的能动作用,将理性融入其中与情感进行平衡,实现安全管理的优化。  相似文献   
79.
为了精确有效地提取声波法检测气井环空液位的回波周期,在分析环空中测试波的传播特征及基音周期检测的基础上,提出1种基于检测信号短时自相关函数(ACF)及平均幅度差函数(AMDF)的液面回波周期提取方法;利用自主搭建的室内模拟实验系统开展了不同初始环空压力下环空液位检测实验;对检测信号进行中心削波处理并计算ACF/AMDF,提取出液面回波周期并与理论计算值对比分析;同时分析了现场环空液位检测信号,提取其回波周期。研究结果表明:提出的新方法能有效地用于提取环空液面回波周期;室内实验中,该方法最大误差绝对值为1.54%;该方法能够有效抑制液面回波信号中的随机噪声及接箍反射波等,处理后的信号曲线在回波周期处峰值更加突出、集中,而在其他位置更加平滑,提高了对液面回波周期特征的辨识能力。  相似文献   
80.
阐述了水生态健康的内涵与意义,从江苏省率先在太湖流域开展水生态环境功能分区管理的顶层设计,构建以水生态健康指标为核心的水生态健康评估技术体系,地方对照水生态环境功能区划的水生态分级管控目标开展的应用与实践结果等3个方面,回顾了江苏省太湖流域水生态健康评估工作的主要进展,提出了完善水生态健康评估技术体系和推进流域水生态健康评估工作的建议。  相似文献   
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