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61.
Abstract

Standard No. EN 15831:2004 provides 2 methods of calculating insulation: parallel and serial. The parallel method is similar to the global one defined in Standard No. ISO 9920:2007. Standards No. EN 342:2004, EN 14058:2004 and EN 13537:2002 refer to the methods defined in Standard No. EN ISO 15831:2004 for testing cold protective clothing or equipment. However, it is necessary to consider several issues, e.g., referring to measuring human subjects, when using the serial method. With one zone, there is no serial-parallel issue as the results are the same, while more zones increase the difference in insulation value between the methods. If insulation is evenly distributed, differences between the serial and parallel method are relatively small and proportional. However, with more insulation layers overlapping in heavy cold protective ensembles, the serial method produces higher insulation values than the parallel one and human studies. Therefore, the parallel method is recommended for standard testing.  相似文献   
62.
论证限期治理是可诉的具体行政行为,探讨限期治理及其行政处罚的主体适格问题,通过对相关法律规范的剖析和质疑,澄清多种模糊认识,并提出一些建设性意见。  相似文献   
63.
基于建筑全生命周期这个主线,建筑可持续发展视角下供应链协调与社会责任共担机理研究,以绿色建筑供应链运行效率为导向,以既有建筑节能改造效率为切入点,以产业链过程中各主体行为规律为基础,采用“总-分-合”的基本研究思路模式,聚焦了“主导企业驱动下绿色建筑供应链协调机理与策略、既有建筑节能改造主体社会责任共担机理、建筑废弃物再生利用产业链主体社会责任共担机理”等三部分核心内容,初步形成建筑可持续发展视角下供应链协调与社会责任共担机理的理论体系。本成果采用“总-分-合”的思路模式,基于循环经济理念和主体行为策略视角,遵循研究的学理逻辑,以研究生学位论文为基础,开展“主导企业驱动下绿色建筑供应链协调机理与策略、既有建筑节能改造主体社会责任共担机理、建筑废弃物再生利用产业链主体社会责任共担机理”3个子课题研究,从系统整体概况实施全面研究规划着手,构架了总括、绿色建筑供应链协调机理、既有建筑节能改造主体社会责任共担、建筑废弃物再生利用社会责任共担、总结等五大模块及上中下三大篇共12章的系统体系。  相似文献   
64.
本文首先从环境容量利用权产生的社会背景和自然科学基础出发,指出环境容量利用权是一种新型无形财产权,是对环境生态功能的商品化,兼具公权与私权属性.然后,本文深入探讨了环境容量利用权的权利构造,指出环境容量利用权的主体不限于排污者,而是一般主体,但要成为具体的环境容量利用权主体还需受到一定的公法管制;环境容量利用权的客体就是环境容量,通过环境容量所依附的物质载体的空间范围、利用环境容量的期限、所利用的环境容量的数量、所排放污染物的种类等参数可使环境容量具有确定性;环境容量利用权的核心权能是排污和收益,环境容量利用权的功能定位是利用而非支配或控制环境容量,一般不具有占有和排他权能,通过排污保证正常的生产活动是间接收益,而通过交易获取经济利益则是直接收益.最后,本文简要分析了环境容量利用权在中国的实现机制.  相似文献   
65.
人类生存环境是可持续发展的基石 ,其命运如何 ,取决于主体自我约束意识的成熟程度 ,因而 ,它是哲学必须面对的课题  相似文献   
66.
Urban open space provides a number of valuable services to urban populations, including recreational opportunities, aesthetic enjoyment, environmental functions, and may also be associated with existence values. In separate meta-analyses of the contingent valuation (CV) and hedonic pricing (HP) literature we examine which physical, socio-economic, and study characteristics determine the value of open space. The dependent variable in the CV meta-regression is defined as the value of open space per hectare per year in 2003 US$, and in the HP model as the percentage change in house price for a 10 m decrease in distance to open space. Using a multi-level modelling approach we find in both the CV and HP analyses that there is a positive and significant relationship between the value of urban open space and population density, indicating that scarcity and crowdedness matter, and that the value of open space does not vary significantly with income. Further, urban parks are more highly valued than other types of urban open space (forests, agricultural and undeveloped land) and methodological differences in study design have a large influence on estimated values from both CV and HP. We also find important regional differences in preferences for urban open space, which suggests that the potential for transferring estimated values between regions is likely to be limited.  相似文献   
67.
当前有关流域生态补偿的研究和实践探索,均倾向于从责任分配视角来设定流域生态补偿的适用条件。然而,从责任分配视角来界定流域生态补偿之适用条件面临着诸多困境。以水质控制目标作为适用条件的地方立法和以超过Ⅲ类水质标准作为流域生态补偿适用条件之观点,均限缩了流域生态补偿的适用范围,导致了补偿义务主体与受偿主体之间法律关系的混乱,并背离了流域生态补偿的本质和基本功能预设。无论从流域生态补偿的功能定位出发,还是基于该制度构建的正当性基础和可行性考量,均应从权利确认而非责任分配视角来明晰流域生态补偿之适用条件。首先,流域生态补偿的基本功能是流域生态利益正向供给激励,受偿主体的权利确认与保障是这一制度构建的重心。从责任分配的角度来界定流域生态补偿之适用条件,将导致其基本功能的偏离;其次,"最少受惠者的最大利益"原则是流域生态补偿制度构建的正当性基础,流域生态补偿的本质是对"最少受惠者"发展权的弥补。从责任分配视角界定流域生态补偿之适用条件遮蔽了流域生态补偿法律关系中的"最少受惠者";再次,受益主体的非特定性意味着从权利确认视角来界定流域生态补偿之适用条件将更具有可行性。从权利确认视角来看,流域生态补偿的适用条件应包括:有生态增益行为、非有责主体、不问主观动机与现实损害后果。  相似文献   
68.
Is there a common metals demand curve?   总被引:1,自引:0,他引:1  
Previous studies have identified a single, stable and strong correlation between the price of metals and their consumption, such that low priced metals are always used in large amounts and visa versa. Some have interpreted this as evidence that metals share a common demand curve so that a single price elasticity of demand exists. This paper reviews and tests this hypothesis against a number of other possible explanations, including the idea that the relationship is an empirical curiosity. Modifications to the demand curve were tested by allowing metals to have different intercepts and price elasticities. The results from this analysis suggest that metals do not share a common demand curve and that the correlation identified between the price of metals and their level of consumption is an empirical curiosity. As such, the singular price elasticities published in past papers should not be used for assessing future rates of metals substitution.  相似文献   
69.
ABSTRACT: Increasing block-rate prices for irrigation water were implemented during 1989 in a 10,000-acre irrigation district in California's San Joaquin Valley. The program motivated improvements in irrigation practices that reduced the volume of water delivered to farm fields and the volume of drain water collected in on-farm drainage systems. The ratio of net crop water requirements to field deliveries increased from 0.65 in 1988 to 0.73 in 1989. The volume of drain water collected at a subset of 20 drainage systems was reduced by 351.1 acre-feet (11.5 percent). Estimated loads of salt, boron, and selenium were reduced by 2,407 tons (11.0 percent), 3.33 tons (11.0 percent), and 0.07 tons (9.2 percent).  相似文献   
70.
ABSTRACT: Pricing policy in water allocation has become of more concern as some areas find water is indeed a scarce resource. Demand estimates, where the quantity purchased-value in use relationships are of concern, have been made in other studies for residential, industrial, and agricultural uses in many areas of the country. The price-quantity relations for water use in commercial firms are estimated and discussed for several different types of stores in this study. A derived demand model is used to estimate commercial demand in the Miami, Florida, area. The price elasticity was generally low (inelastic) for all groups studied except for department stores. This group was found to have an elastic demand for water at all prices above $0.93 per thousand gallons purchased per month, where the mean price for this part of the sample was $1.24. The major implication of the study is that commercial establishments may be responsive to price changes over the long run, much as has already been shown for other types of user groups in other studies.  相似文献   
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