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341.
Min-Yuan Cheng Yi-Hsu Ju Yu-Wei Wu Sylviana Sutanto 《International Journal of Green Energy》2016,13(15):1599-1607
Nowadays, biodiesel is used as one of the alternative renewable energy due to the increasing energy demand. However, optimum production of biodiesel still requires a huge number of expensive and time-consuming laboratory tests. To address the problem, this research develops a novel Genetic Algorithm-based Evolutionary Support Vector Machine (GA-ESIM). The GA-ESIM is an Artificial Intelligence (AI)-based tool that combines K-means Chaotic Genetic Algorithm (KCGA) and Evolutionary Support Vector Machine Inference Model (ESIM). The ESIM is utilized as a supervised learning technique to establish a highly accurate prediction model between the input--output of biodiesel mixture properties; and the KCGA is used to perform the simulation to obtain the optimum mixture properties based on the prediction model. A real biodiesel experimental data is provided to validate the GA-ESIM performance. Our simulation results demonstrate that the GA-ESIM establishes a prediction model with better accuracy than other AI-based tool and thus obtains the mixture properties with the biodiesel yield of 99.9%, higher than the best experimental data record, 97.4%. 相似文献
342.
Anneleen Kenis 《环境政策》2016,25(6):949-970
Grassroots environmental movements have recently started to question the focus on sustainable consumption as a main strategy to tackle climate change. They prefer to address individuals as citizens rather than as consumers, and focus on collective rather than individual change. Two prominent movements in this regard are Transition Towns and Climate Justice Action. While both movements criticise conventional approaches, they put forward entirely different strategies for what has to happen instead. Based on extensive qualitative research, this article analyses how these movements manifest themselves in Flanders (Belgium). The focus is on their different accounts of how and why collective practices have to be built, and the place they attribute to ‘the political’ in this. The analysis reveals the existence of two different forms of ecological citizenship: one communitarian, the other agonistic. 相似文献
343.
Nicolas Tchertchian Dominique Millet Pierre Alain Yvars 《International Journal of Sustainable Engineering》2016,9(4):277-290
The tendency towards a homogenous mode of development modelled on that of Western countries means that sustainable development has become increasingly urgent. It is necessary to thoroughly redefine products and their expected performances in such a way that the consequences are compatible with sustainable development. In the domain of product design, this means that it is no longer sufficient to use assessment tools “after the fact” to check the impact of products whose functional unit (FU) was defined prior to production; it is now necessary to rethink the definition of the FU itself. This article aims to present an approach based on a combination of life cycle analysis methods and problem-solving by constraint satisfaction. This original approach makes it possible to vary the design of the different dimensions of the FUs of a complex system and thus to make it easier to identify the best architecture along with the best functional definition of the system. In this study, the EcoCSP approach is applied to define the functional performances of an ecological passenger ferry. The complexity of couplings between subsystems and the sheer number of those subsystems mean that the designer has to use “intelligent” tools. These simulate a great number of scenarios and help him/her to fine-tune the system and make the right technological choices with regard to the right functional specifications. 相似文献
344.
S. Alvandi W. Li M. Schönemann C. Herrmann 《International Journal of Sustainable Engineering》2016,9(6):354-362
Value stream mapping (VSM) is a well-accepted tool within lean manufacturing concept which is often used for analysing and designing the flow of materials and information required to manufacture a product. However, the analysis is static and single product oriented, which fails to cope with either the variation of production plan or a multi-product environment. In addition, the environmental impact of a manufacturing system is highly associated with the dynamic consumption of energy and resources. Despite the recent integration of VSM with simulation or environmental studies (in the domain of energy efficiency), still neglected is the dynamic assessment of all the resources involved in a multi-product production environment. This paper presents a methodology for modelling multi-product manufacturing systems with dynamic material, energy and information flows with the aim to generate economic and environmental value stream maps (E2VSM). The proposed methodology is validated with an industrial case. 相似文献
345.
Justina Catarino João Henriques Anabela Maia 《International Journal of Sustainable Engineering》2016,9(1):35-46
The activities developed within an eco-efficiency project in mineral industries located in the largest area for marble extraction in Portugal, in Alentejo region, in the Estremoz – Borba and Vila Viçosa anticline are presented in this paper. The project was designed to apply the sustainability concept in seven companies of marble extraction and transformation. The adopted strategy used new cleaner production models together with sustainable value (SV) improvement, leading to the rationalization of the industrial process, the involvement of economic agents and the orientation of the management of production processes towards eco-efficiency. The challenge was to have the mineral industry managing efficiently the resources on which the business depends, according to sustainability principles. Different opportunities for improvement, related to the minimization of materials, water and energy use, were identified in the companies. Some proposals mainly related to social improvement and small and medium-sized enterprise competitiveness benefits were also selected and discussed. This approach allows the integration of sustainability at company's and region's levels by combining in the entrepreneurial activity the creation of wealth together with the environment protection and the achieving of social benefits. Highlights: The involvement of different stakeholders in the project (Eco-efficiency in Portuguese companies of marble sector) was positive in the discussion and search of solutions for companies. It is possible to involve marble extraction and processing companies in eco-efficiency improvement towards sustainability. Companies from the marble sector improved environmental and social performance and reduced the costs of their production processes by applying SV methodology. 相似文献
346.
资源与环境约束加剧的大背景下,在"生态门槛"内实现社会福利最大化的可持续发展模式是未来城市发展的必然选择。从生态福利绩效视角出发,选取人均生态足迹和人类发展指数构建城市可持续发展评价指标体系,并采用DEA方法计算二者的投入产出效率,对上海市1999~2012年可持续发展水平进行多维度、动态化的实证分析。研究发现:1上海市人类发展指数、人均生态足迹与经济发展同步增长,但人均生态足迹水平大于生态承载能力,处于严重"生态赤字"状态,并不断恶化;2上海市多数年份的生态福利绩效处于DEA无效状态,且2005年以来进入规模收益递减通道。最后提出政策建议。 相似文献
347.
The study focuses on evaluating factors that farmers consider relevant in adopting cassava production in five semi-arid zone
of West African countries. The study is based on primary data randomly collected as part of collaborative study of cassava
in semiarid zones of Africa (COSCASSA) village level survey from five West African countries namely: Nigeria, Ghana, Chad,
Niger and Burkina Faso. This study models effects of farm, farmer and technology specific factors on the decision of semi
arid farmers to adopt cassava into their farming system. By way of threshold decision models—Probit and Logit models, the
estimation of each country and the pooled data adoption models reveal different adoption models for the countries considered.
For each country, different variables appeared as major adoption shifters. Comparatively, the adoption models for Nigeria
and whole region appear to have the highest significance variables, being seven in number. This is followed by Chad (6), Ghana
(4), and Burkina Faso and Niger with three each. For the variables considered, distance to nearby urban market appears a major
adoption shifter in all the country, except for Niger. This is closely followed by contact with extension, variety, pest/disease
resistance and livestock feeds, which appear significant in four of the countries. Membership of cooperative societies appears
as the least adoption predictor, which is only significant in Chad republic. The study therefore recognizes the importance
of varietial characteristics and farmers’ characteristics in acceptance of cassava as a major root tuber crop in the semi
arid region of West Africa.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
348.
349.
This paper analyzes the United Nations Organization's Kyoto Protocol nations to address two questions. First, what are the environmental production efficiency rankings of these nations? Second, is there a relationship between a nation's ratification status and its environmental production efficiency ranking? Our findings suggest that the nations that have ratified the Kyoto Protocol are more likely to be environmentally production efficient as compared to the nations that have not ratified the Protocol. 相似文献
350.
论我国国际河流可持续开发利用的问题与法律对策 总被引:1,自引:0,他引:1
中国是世界上国际河流最多的国家之一,在国际河流的开发利用方面采取了一定的措施并取得了一定的成绩,但是在国际河流的可持续开发利用中仍存在不少问题,需要完善相关的国际与国内法律制度并采取其他有效的措施予以解决。从中国国际河流的概况出发,阐述对其进行可持续的开发利用在促进中国经济发展、加强民族团结以及保障国防安全等方面的重大意义,进而分析中国国际河流在可持续开发利用中存在的问题,包括立法缺失、保障措施缺位、管理机构缺乏等,最后从完善可持续开发利用的前提要素、确立可持续开发利用的基本原则、完善可持续开发利用的立法以及积极参与可持续开发利用的国际合作等方面提出解决上述问题的对策思考,以促进和保障我国国际河流可持续开发利用的实现. 相似文献