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51.
The purpose of this study is to analyze the cost structure of a sample of Italian wastecollection firms in order to assess economies of scale and density and, therefore, definethe optimal size of the firms. A total and a variable translog cost function were estimated using panel data for a sample of 30 firms operating at the provincial level over the period 1991–1995.The empirical evidence suggests that franchised monopoly, rather than side-by-sidecompetition, is the most efficient form of production organization in the waste collection industry. Further, the majority of firms are not operating at optimal scale.  相似文献   
52.
死刑制度的存废与死刑制度的取向一直是中国理论与立法界争论的热点问题之一,中国现行的死刑制度的存在有其一定的合理性,但在限制和废除死刑的国际趋势下,中国在刑事立法上是否也应该全面废除死刑制度。本文以此为视角,对这一问题进行粗浅的探讨。  相似文献   
53.
电子废弃物循环利用技术现状   总被引:1,自引:0,他引:1  
电子废弃物是一种宝贵的二次资源,但是如果处理不当将会造成资源浪费和严重的环境污染.介绍了电子废弃物的特点,以及国内外电子废弃物的处理技术现状.  相似文献   
54.
通过建立基于费用流的废纸动态回收网络模型并求解,解决废纸在运输网络中流动的路径问题,避免了经典运输问题无法直接体现转运和路径选择的问题,最后通过一个模拟算例验证了模型的优越性。  相似文献   
55.
This study investigates the coverage of solid waste management on 1142 websites maintained by companies, news media and non‐governmental organizations to validate an automated approach to content and language analysis. First, a frequency analysis of waste management terms sheds light on the breadth and depth of their environmental discourses, revealing that corporate and media attention to waste management is small compared with that of non‐governmental organizations. Second, an investigation of their attitudes toward waste management suggests that companies avoid negative information in environmental communication, unlike news media or non‐governmental organizations. Ultimately, an automated tool for ontology building is employed to gain insights into companies' shared understanding of waste management. The ontology obtained indicates that companies conceptualize waste management as a business process rather than framing it from an ecological perspective, which is in line with findings from previous research. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.  相似文献   
56.
给出了轮胎平均使用年限和轮胎报废量计算方法。依据统计数据计算,我国汽车和摩托车外胎使用年限平均为1.9年和2.7年。测算废汽车和摩托车外胎重量为10 kg和1 kg左右。2011~2015年全国及各省市废轮胎产生量逐年增加,废汽车外胎占废轮胎总量的90%以上,是废轮胎回收的重点。  相似文献   
57.
This paper addresses the problem of designing a household waste collection system for rural insular areas using a barge for transportation, based on a novel mixed integer programming model that simultaneously integrates decisions of waste collection sites selection within the islands to be served, visit schedule for each selected collection site, and multi-period vehicle routing. An application to a real-world instance consisting of small rural islands located in the south of Chile shows the effectiveness and complexity of the model, along with the advantages of using a waste compactor instead of transporting the waste using bins onboard a barge.  相似文献   
58.
晏殊《珠玉词》之艺术特色,前人公认为风流闲雅,这一风格的形成主要得益于清新淡雅的意象、华美明丽的色彩、珠圆玉润的声韵、和谐动听的词调。  相似文献   
59.
白色污染已经成为当今环境保护领域里的大问题。国家为此制定了一系列的政策法规,各级地方政府也出台了“禁白”措施,但效果不尽人意。本文对“白色污染”的发生和对策进行了探讨,认为“禁白”不是最好的治理办法,应该在回收和再利用方面作努力。  相似文献   
60.
The nutritional habits of UK consumers have become a cause for concern with an increasing number of people suffering from diseases related to nutrition. The way in which food is prepared may contribute to the nutritional content of the diet. Traditional methods of cooking and eating are being influenced by increased ownership of domestic appliances. This study aimed to carry out a cross sectional study of people living on Merseyside to determine the ownership and use of small kitchen domestic appliances in relation to the possible consequences the appliances may have on the nutrient intake of the individual. An opportunistic sample of 276 female adults aged 25–70 years was recruited from amongst university staff and community groups within Merseyside. Data were collected using a self‐completion questionnaire consisting of questions concerning personal details, the ownership and use of domestic appliances that may influence nutrient intake. The Liverpool John Moores University Ethics Committee granted ethical approval. Microwave ovens, electric toasters and grills were owned by 80% of the population. Coffee makers, handheld electric food mixers, sandwich makers, blenders and food processors although owned by over 45% were used by the majority only once a week or less. Newer items such as a bread maker were owned by 9% who were significantly more likely to have a professional occupation. Those with unskilled occupations were significantly more likely to own a deep fat fryer and least likely to own a food processor. Those aged 25–34 years were significantly least likely to own a handheld food mixer. Households comprised of couples with or without children were significantly more likely to own sandwich makers, bread makers, food processors and handheld food mixers. No difference in the use of the appliances was found with occupational group or age. A large percentage of people own a variety of domestic appliances, the use of which may have a beneficial effect on their nutrient intake, however, it is of concern that those in the lower socio‐economic group were more likely to own appliances that will have a negative effect on their diet.  相似文献   
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