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51.
非畅流流域跨界水污染纠纷管理模型研究   总被引:4,自引:0,他引:4       下载免费PDF全文
结合我国流域的非畅流特点,提出了流域各地区作为独立决策单元、污染物人为调控和地区间污染物间接不影响等几个基本假设,构建了我国流域跨界水污染描述模型.分析了我国目前正在执行的污染物削减指令配额模型的优缺点,提出用行政、税收、排污权交易等手段解决我国日益严重的流域跨界水污染纠纷问题,为此建立了合作协调模型、税收宏观调控模型、排污权交易宏观调控模型.通过对淮河流域跨界水污染纠纷的具体应用分析了各种管理模型的资源利用效率.最后,通过各种管理模型的对比分析,指出选择合适的管理模型应与流域的实际情况相匹配.  相似文献   
52.
流域跨界水污染纠纷税收调控管理模型研究   总被引:3,自引:1,他引:3  
在分析我国目前的指令配额管理模型和排污收费制度存在的诸多问题的基础上,提出用税收手段解决我国日益严重的流域跨界水污染纠纷的思路。结合我国流域的非畅流特点,提出了污染物人工调控和污染物间接不影响等几个基本假定,构建了流域跨界水污染结构描述模型。建立了流域跨界水污染税收调控Stackelberg博弈模型,并用理想点法求解出博弈模型的数值解。通过淮河流域的实证分析,得出税收调控管理模型明显优于指令配额管理模型的结论。最后分析了影响税收调控管理模型实施效果的诸多因素。  相似文献   
53.
基于主体不平等的跨国界河流水资源分配的破产博弈研究   总被引:1,自引:0,他引:1  
基于破产理论和讨价还价博弈,构建水资源分配的破产博弈模型。借鉴国际水法,构建主体在水资源分配谈判中的议价能力评价指标体系,将议价能力运用到破产博弈模型中,突出主体在水资源分配中的不平等性,减少水资源分配量与贡献、需求量和对水资源依赖程度的非对称性;结合主体的谈判破裂点,根据主体满意度函数的联动函数寻找水资源分配的最优解,使分配能同时满足个体理性和集体理性,并对澜沧江-湄公河流域进行实例研究。  相似文献   
54.
以我国2011-2016年A股制造业上市公司为研究样本,本文采用面板回归模型实证检验了企业水信息披露对企业价值的影响以及异质机构投资者在二者关系中的调节作用。结果表明:目前企业水信息披露水平整体较低,其对企业价值有显著的负向影响;在该影响中,机构投资者整体有显著的正向调节作用,压力抵制型机构投资者有显著的负向调节作用,而压力敏感型机构投资者无显著的调节作用。  相似文献   
55.
The aim of this study was to develop a modified quantitative microbial risk assessment (QMRA) framework that could be applied as a decision support tool to choose between alternative drinking water interventions in the developing context. The impact of different household water treatment (HWT) interventions on the overall incidence of diarrheal disease and disability adjusted life years (DALYs) was estimated, without relying on source water pathogen concentration as the starting point for the analysis. A framework was developed and a software tool constructed and then implemented for an illustrative case study for Nepal based on published scientific data. Coagulation combined with free chlorine disinfection provided the greatest estimated health gains in the short term; however, when long‐term compliance was incorporated into the calculations, the preferred intervention was porous ceramic filtration. The model demonstrates how the QMRA framework can be used to integrate evidence from different studies to inform management decisions, and in particular to prioritize the next best intervention with respect to estimated reduction in diarrheal incidence. This study only considered HWT interventions; it is recognized that a systematic consideration of sanitation, recreation, and drinking water pathways is important for effective management of waterborne transmission of pathogens, and the approach could be expanded to consider the broader water‐related context.  相似文献   
56.
Abstract

A central objective of empirical research on treatment response is to inform treatment choice. Unfortunately, researchers commonly use concepts of statistical inference whose foundations are distant from the problem of treatment choice. It has been particularly common to use hypothesis tests to compare treatments. Wald’s development of statistical decision theory provides a coherent frequentist framework for use of sample data on treatment response to make treatment decisions. A body of recent research applies statistical decision theory to characterize uniformly satisfactory treatment choices, in the sense of maximum loss relative to optimal decisions (also known as maximum regret). This article describes the basic ideas and findings, which provide an appealing practical alternative to use of hypothesis tests. For simplicity, the article focuses on medical treatment with evidence from classical randomized clinical trials. The ideas apply generally, encompassing use of observational data and treatment choice in nonmedical contexts.  相似文献   
57.
The aim of this study is to measure and describe symptoms of eating disorders among females in treatment for drug addiction in Norway. Previous clinical and epidemiological studies have revealed coprevalence between eating disorders and substance use or abuse. However, few studies have measured eating disorders in drug-using samples and even fewer within the context of drug treatment. In this study, 29 females with drug use disorder in residential treatment were tested with the Eating Disorder Inventory–2. A subgroup of 9 females (31%) with significant symptoms of eating disorders was identified. The characteristics of this group and possible clinical consequences are discussed.  相似文献   
58.
Parents with substance use disorders (SUD) require treatment and support in order to provide children with appropriate care and protection. Using the 2012 National Child Abuse and Neglect Data System (NCANDS), this paper analysed 464 313 substantiated child maltreatment reports to determine (i) the proportion and characteristics of reports involving substance abuse; and (ii) the child and caregiver/perpetrator (C/P) characteristics that predicted referral to treatment as recorded in service plans. Findings indicate that 12% (N = 53 234) of maltreatment reports involved C/P SUD. Yet, of those reports, only (19%) (N = 10 088) were referred to substance abuse treatment as part of their service plan, indicating a large gap between those who need treatment and those who receive it. This finding is important given that parental SUD is consistently linked to poorer child outcomes. Amongst other variables, reports indicate that C/P with co‐occurring emotional disturbance were three times more likely to be referred to treatment for SUD as part of service plans. Additional research is needed regarding the characteristics that distinguish C/P who receive referrals for SUD treatment in substantiated cases of child maltreatment.  相似文献   
59.
This paper investigates differential customer racial reaction to negative and positive publicity related to professional athletes. In terms of negative publicity, it analyzes the effect of mention in the Mitchell Report on the price of baseball cards. In regards to positive publicity, it considers the impact of having been identified as a member of the United States Olympic or national team. After controlling for player productivity with performance statistics, the effects of being mentioned in the Mitchell Report are isolated within regression analysis to draw conclusions concerning customer racial attitudes toward the steroids scandal. Similar analysis is conducted to see the impact of being seen as a baseball representative of the United States. Regression results are consistent with the conclusion that negative publicity devalues the cards of nonWhite players but not of White players. Positive publicity, however, increases the value of a player's card regardless of ethnicity.  相似文献   
60.
沙水游戏包括玩沙游戏、玩水游戏、沙水结合的游戏。沙水游戏在幼儿科学教育中的价值主要体现在激发幼儿对自然界的好奇心,培养其专注度;激发其探究欲望,培养其探究能力;积累科学经验和感性认识,促进科学认知发展;帮助建立正确的科学前概念等方面。因此,应该积极利用沙水游戏来开展幼儿科学教育。  相似文献   
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