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131.
A triple-objective optimal sizing method based on a dynamic strategy is presented for an islanded hybrid energy microgrid, consisting of wind turbine, solar photovoltaic, battery energy storage system and diesel generator. The dynamic strategy is given based on a dynamic complementary coordination between two different master-slave control modes for maximum renewable energy utilization. Combined with the proposed strategy, NSGA-II-based optimization program is applied to the sizing optimization problem with triple different objectives including the minimization of annualized system cost, the minimization of loss of power supply probability and the maximization of utilization ratio of renewable energy generation. The sizing results and the proposed strategy are both compared and analyzed to validate the proposed method in a real case of an islanded hybrid energy microgrid on Dong’ao Island, China. 相似文献
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133.
Niedzielski P 《Environmental monitoring and assessment》2006,118(1-3):231-246
This paper presents the results of the determination of arsenic, antimony and selenium concentrations of inorganic speciation
in surface water samples from Gniezno city (western Poland) and its neighborhood. The concentration of elements were up to
1.85 ng/ml for arsenic, 1.61 ng/ml for antimony and 0.45 ng/ml for selenium (detection limits: 0.04 ng/ml for As and Sb and
0.03 ng/ml for Se). A variety of concentrations for the determined elements has been obtained in waters from Gniezno city’s
neighborhood and in water from down-town reservoirs which are under strong anthropogenic pressure. 相似文献
134.
通过对典型发电与高压输变电工程工频电磁场的现场检测,阐明了发电与高压输变电工程的工频电磁场现状.在此基础上,根据科学界关于极低频电磁场对人体短期和长期效应研究的明确结论,介绍了发电与高压输变电工程的工频电磁场暴露对人体健康的影响.同时,从卫生安全的角度提出了防止和减少工频电磁场影响的综合防护措施,其中包括:慎重选址,合理设计,适当个体防护和必要的警示标识.另外,扼要地介绍了工频电磁场的有关卫生标准和测量方法. 相似文献
135.
Toward knowledge structuring of sustainability science based on ontology engineering 总被引:1,自引:1,他引:0
Terukazu Kumazawa Osamu Saito Kouji Kozaki Takanori Matsui Riichiro Mizoguchi 《Sustainability Science》2009,4(1):99-116
In sustainability science (SS), it is difficult to identify what needs to be solved, and it is also not clear how to solve the problems that are identified. There has been no consensus on the underlying question of “What is structuring knowledge in SS?” This paper focuses on knowledge structuring accompanied by supporting of thinking. It addresses the key challenges associated with knowledge structuring in SS, identifies the requirements for the structuring of knowledge, proposes a reference model, and develops an ontology-based mapping tool as a solution to one layer of the reference model. First, we identify the important requirements for SS knowledge structuring. Second, we develop a reference model composed of five layers based on three of the requirements. Third, we develop an ontology-based mapping tool at Layer 2 of the reference model for meeting the two major challenges for SS, namely, identifying what problems should be addressed in SS itself and proposing solutions for those problems. The tool is designed to store and retrieve information regarding SS, to provide access to a prototype ontology for SS, and to create multiple maps of conceptual chains depending on a user’s interests and perspectives. Finally, we assess whether the developed tool successfully realizes the targeted part of the reference model for SS by examining the tool’s conformity to the reference model, as well as its usability, effectiveness, and constraints. Although several issues were identified in the prototype ontology and the mapping tool, the study concluded that the mapping tool is useful enough to facilitate the function of Layer 2. In particular, the mapping tool can support thinking about SS from the viewpoint of: (a) finding new potentials and risks of technological countermeasures studied in SS; (b) helping users to get a more comprehensive picture of problems and their potential solutions; and (c) providing an effective opportunity to come up with new ideas that might not be thought of without such a tool. 相似文献
136.
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138.
系统动力学方法在城市生活垃圾产生系统的应用 总被引:6,自引:0,他引:6
准确预测城市生活垃圾产生量是构建与运行生活垃圾管理系统的首要条件. 我国大部分城市生活垃圾的历史统计数据稀缺,传统预测方法往往难以得到要求精度的预测结果. 在系统地分析生活垃圾产生量影响因素及因素间互动关系的基础上,建立了基于VENSIM软件的系统动力学模型,并将该模型应用于深圳市城市生活垃圾产生系统. 结果表明:运用系统动力学方法可以较好地进行城市生活垃圾产生量预测,解决了数据稀缺条件下城市生活垃圾产生量的精确预测问题,为处理处置工艺的选择和规模的确定提供了数据支撑,同时可以在垃圾产生量预测的基础上进行不同政策下系统的行为模拟. 相似文献
139.
The amount of solid waste in the vicinity of the river Ganga increased rapidly during the festive days of Ardh-Kumbh. The
initial amount of solid waste was 775.0 kg, observed on 30th January 2004 in the Har Ki Pauri area, which increased to 4,550.0 kg
on the main bathing day of 4th May 2004, showing nearly a six-fold increase. The total amount of solid waste collected during
nine days of observations was 23,865.0 kg. The rate of solid waste generation fell sharply during the following week, after
the main bathing day, and was found to be 1,155.0 kg, which is still about 14.90% higher than the initial value. 相似文献
140.
酒店主要产品服务经济-能源-环境系统分析 总被引:4,自引:0,他引:4
利用投入产出分析方法和能耗寿命周期分析方法相结台。建立了主要产品中间生产和最终服务经济-能源-环境系统投入产出综合计算模型;对国内有代表性的八家酒店主要产品服务系统进行了计算与综合分析:结果显示酒店之间投入产出指标值量大相差2倍以上。具有巨大的改进潜力;酒店内部餐饮服务系统是传统的线性开放式经济发展模式的突出代表。应进行蕾业规模调整、合理配置能源种类和消耗比例、重点实施清洁生产。 相似文献