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《Simulation Modelling Practice and Theory》2012,20(10):2189-2205
To encourage the adoption of solar power as well as new technological improvements in solar industry, state and federal governments have employed various kinds of incentives over the past decades, such as rebates, tax return opportunities, and Net Metering credits. At the same time, however, the governments concern regulations to avoid highly steep growth of solar energy without considering necessary supporting structure such as storage components, which will increase the electricity price and threaten the stability of existing transmission systems. The goal of this research is to develop a decision support tool to analyze the effectiveness of various policies (both incentives as well as regulations) on the proper growth rate of distributed photovoltaic (PV) systems avoiding the instability of the transition system or steep rising of the electricity price. To this end, we propose a hybrid two-level simulation modeling framework, which is significantly more detailed than the simplified structures commonly used in most policy evaluations. The lower-level model concerns the calculation of PV system payback period of individual household based on hourly electricity generation (PV) and consumptions, incentive levels, PV module price, and hourly electricity price (grid). The higher-level model, running on a weekly basis for 20 years, concerns the household adoption behaviors of the PV systems influenced by various factors, including payback period, household income, word-of-mouth effect and advertisement effect. Agent-based and system dynamics modeling techniques are leveraged in both levels. The proposed models have been developed for residential areas at two different regions in the US based on real data, which have been used to illustrate the impact of policies in different regions. 相似文献
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英国对食品安全责任主体法律责任立法的借鉴研究 总被引:1,自引:0,他引:1
我国食品安全事故之所以屡禁不止,一个重要原因就是对食品生产经营者处罚力度过轻甚至对有些行为没有规定相应和相当的处罚。《中华人民共和国食品安全法》从颁布实施4 年多的效果来看,法律中仍存在不少问题。食品安全问题并不是我国独有的社会现象,英国在第一次工业革命时期也经历了食品安全从混乱到有秩的过程,这与其食品安全立法的逐渐完备有着密切关系,值得我国借鉴。本文通过对英国食品安全立法的演变历史研究,探讨了我国相关立法的借鉴之处,并提出3 项立法修订建议,达到强化我国食品安全责任主体法律责任,改善我国食品安全现状的目的。 相似文献
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《Journal of Great Lakes research》2020,46(5):1459-1468
Lake Tana is the most important freshwater lake in Ethiopia. Besides pressures on water quality resulting from urbanization and deforestation, the invasion of the exotic water hyacinth (Eichhornia crassipes) poses new threats to the ecosystem. Water hyacinth, endemic to South America, is widely considered as the world’s worst aquatic invasive weed. In 2011, the weed appeared on the northern shores of Lake Tana, expanding in south-eastern direction. The lake area affected by water hyacinth was last estimated in 2015 at 34,500 ha, which equals 16% of the total lake surface. In this research, the benefits of water hyacinth control and eradication for the rural population inhabiting the northern and north-eastern villages bordering Lake Tana, are investigated. In the area, the population largely depends on farming and fishing. An assessment of the total economic benefit of eradication was conducted. The stakeholder-centered approach led to measuring the willingness to contribute in labor and cash terms. Results showed smallholders in the study are willing to contribute over half-a-million euros annually. Costs of management actions can be weighed to the benefits, where further research is needed on the impact on other stakeholder groups. Moreover, wetland management should advance to explore multiple pathways in an integrated approach: water hyacinth control, water hyacinth utilization and sustainable waste water management. 相似文献
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以美国、加拿大、英国、澳大利亚、新西兰及中国为研究对象,通过对2008-2010年食品召回数据和信息进行分析,得到不同国家近年来食品召回的特点、变化和趋势。进一步比较研究表明:发达国家同样面临食品召回的严峻形势,但是监管有序;美国2009年爆发的沙门氏菌污染导致食品召回激增问题,该问题在加拿大和英国同时显现,表明贸易全球化下食品安全风险向更大范围蔓延和转移的趋势将成常态;发达国家的企业自愿召回比例接近百分之百,并呈普遍现象;引起食品召回的主要原因除了传统的黄曲霉毒素和沙门氏菌以外,标签问题等新的风险有快速上升趋势;中国由于缺乏规范统一的食品召回信息发布平台,所以召回信息数据少,不能真实反映实际状况。基于此,本文提出中国食品召回可以借鉴发达国家做法的4点建议。 相似文献
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从1995年《食品卫生法》首次赋予保健食品法律地位,到如今《食品安全法》的颁布实施,我国保健食品不断发展,与保健食品相关的法律法规和标准也越来越多。为了理顺保健食品法规体系和标准体系的发展脉络,本文以《保健食品注册管理办法(试行)》为核心,按照申请与审批、原料与辅料、标签与说明、实验与检验、生产经营管理、再注册等方面已经颁布的法律、法规、规章和标准进行系统阐述,总结我国保健食品的法规体系和标准体系现状。 相似文献