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911.
Gül Tekin Temur 《International Journal of Sustainable Engineering》2017,10(6):358-383
Many developing countries such as Turkey are still making an effort on building an infrastructure for waste of electrical and electronic equipment (WEEE) reverse logistic network design (RLND) processes. It is obvious that policies/laws/regulations related to WEEE management provide a sustainable framework for implementation in the RLND. The question is here: Does the implementation of WEEE directives make sense in terms of reducing the total cost of the network in the long term? This study aims to compare regulatory and non-regulatory situations of WEEE RLND in developing countries by formulating two models named as ‘regulatory’ and ‘non-regulatory’. Model 1 is considered as sustainable with economic, environmental and social goals, and the quotas imposed by the environmental directive are taken into consideration as the data of product return amount. In Model 2, only economic goal is considered, and product return amount is forecasted using Artificial Neural Network (ANN). A case study is conducted in a recycling company in order to evaluate performance of the proposed models. This study contributes to the relevant literature by (1) comparing the regulatory and non-regulatory situations RL models explicitly and (2) proposing ANN model to forecast EEE product return or WEEE quantity for non-regulatory situation. 相似文献
912.
Maria Calero-Pastor Fabrice Mathieux Daniel Brissaud Jo Dewulf 《International Journal of Sustainable Engineering》2017,10(6):313-325
The design of heating, ventilation and air conditioning systems is still a challenging engineering task which requires experienced and informed decision-making. These systems have a great energy-saving potential at the system level rather than at the level of the individual products of which they are composed. European environmental product policies have been very useful in facilitating a homogeneous rating scheme which can be used to compare the energy performance of different products that provide the same service. This paper proposes a simplified design method which uses the performance of components that are regulated by European product policies to obtain the overall performance of heating systems in residential buildings. It is a flexible method and allows different product configurations to be assessed so as to optimise the system performance during the design phase. The method is tested on a real case study with domestic hot water and space heating systems. The case study shows the potential for improving the heating systems according to the performance levels of its products currently available in the market. Results of the domestic hot water system show that upgrading its storage tank to the maximum energy class (A+) could bring the highest energy savings ( 4162 kWh/y). 相似文献
913.
This paper investigates the extent and the nature of how the urban planning literature has addressed climate change adaptation. It presents a longitudinal study of 157 peer-reviewed articles published from 2000 to 2013 in the leading urban planning and design journals whose selection considered earlier empirical studies that ranked them these journals. The findings reveal that the years 2006–07 represent a turning point, after which climate change studies appear more prominently and consistently in the urban planning and design literature; however, the majority of these studies address climate change mitigation rather than adaptation. Most adaptation studies deal with governance, social learning, and vulnerability assessments, while paying little attention to physical planning and urban design interventions. This paper identifies four gaps that pertain to the lack of interdisciplinary linkages, the absence of knowledge transfer, the presence of scale conflict, and the dearth of participatory research methods. It then advocates for the advancement of participatory and collaborative action research to meet the multifaceted challenges of climate change. 相似文献
914.
Belinda McFadgen Dave Huitema 《Journal of Environmental Planning and Management》2017,60(10):1765-1784
Environmental changes are increasing the need to understand complex cross-scale feedbacks in social–ecological systems. However, consistent conceptualisation of learning associated with environmental governance is lacking, and research mainly centres on individual variables. This paper identifies a typology of such learning, and theorises about configurations of variables. Focusing on experimentation as an intervention geared towards learning, it proposes a definition of policy experiment. A theoretical framework is presented, summarising a typology of experiments based on learning-related variables embedded in design choices, and reflected in institutional rule aggregations. The framework facilitates systematic analysis of real-world cases and testing of hypotheses on the effects of different types of experiment on learning. A case study demonstrates application of the framework. Results suggest future research paths that include attention to additional relevant variables. The findings have relevance for scholars interested in experimentation and learning, and environmental policy-makers considering experimentation to assess policy innovations. 相似文献
915.
The concentration addition (CA) and the independent action (IA) models are widely used for predicting mixture toxicity based on its composition and individual component dose–response profiles. However, the prediction based on these models may be inaccurate due to interaction among mixture components. In this work, the nature and prevalence of non-additive effects were explored for binary, ternary and quaternary mixtures composed of hydrophobic organic compounds (HOCs). The toxicity of each individual component and mixture was determined using the Vibrio fischeri bioluminescence inhibition assay. For each combination of chemicals specified by the 2n factorial design, the percent deviation of the predicted toxic effect from the measured value was used to characterize mixtures as synergistic (positive deviation) and antagonistic (negative deviation). An arbitrary classification scheme was proposed based on the magnitude of deviation (d) as: additive (10%, class-I) and moderately (10 < d 30%, class-II), highly (30 < d 50%, class-III) and very highly (>50%, class-IV) antagonistic/synergistic. Naphthalene, n-butanol, o-xylene, catechol and p-cresol led to synergism in mixtures while 1, 2, 4-trimethylbenzene and 1, 3-dimethylnaphthalene contributed to antagonism. Most of the mixtures depicted additive or antagonistic effect. Synergism was prominent in some of the mixtures, such as, pulp and paper, textile dyes, and a mixture composed of polynuclear aromatic hydrocarbons. The organic chemical industry mixture depicted the highest abundance of antagonism and least synergism. Mixture toxicity was found to depend on partition coefficient, molecular connectivity index and relative concentration of the components. 相似文献
916.
917.
918.
热-力耦合作用对建筑结构火灾安全的影响 总被引:4,自引:3,他引:1
结构火灾安全可以避免建筑物在火灾中坍塌.火灾热环境影响建筑结构的响应,传统的标准火灾环境有一定的局限性,不能完全适用于若干真实火灾场景.因此有必要开展真实火灾环境下建筑结构的热-力响应特性研究,发展有效的工程工具来设计经济安全的结构.近来,性能化的结构火灾安全设计评估方法和相应技术发展迅速,该文给出一种综合考虑热-力耦合作用的结构火灾安全设计评估方法及相应流程.首先通过建筑和燃料特性来预测可能的火灾热环境特性,然后再分析构件和结构的热响应和力学响应特性来判定结构是否会失效,以及可以降低热和力影响的预防失效措施.该文通过案例分析将该方法应用于某中庭钢结构屋顶的防火保护,得到经济合理的防火涂层设计,满足有关防火规范的安全等价要求. 相似文献
919.
Evaluation of oasis ecosystem risk by reliability theory in an arid area: A case study in the Shiyang River Basin, China 总被引:2,自引:0,他引:2
Ecosystem risk is a new concept in understanding environmental problems. It is important to study and develop quantitative methods for regional ecosystem risk analysis. In this study, some new indicators and methods for measuring oasis ecosystem risk were established using reliability theory. These indicators are linked to water resource, which is the key restricting factor in arid area oasis ecosystems. They have clear meanings and can also be compared in different arid area oases. A case study in the Liangzhou oasis of the Shiyang River Basin in China shows how to calculate these ecosystem risk indicators. The results of the case study are as follows: the reliability indicator, risk indicator, stability indicator, and integrated loss indicator of the Liangzhou oasis are 0.686, 0.314, 0.743, and 0.301, respectively. This means that the reliability degree of the oasis's ecosystem safety is 68.6%; the degree of risk that it is unsafe is 31.4%; the stability degree is 74.3%; and 30.1% of the oasis's area is supported by over-exploiting underground water and damaging the lower reaches of the ecosystem. This result can be used as a guide in controlling and managing ecosystem risk in the research area. 相似文献
920.
Elsa T.A. Berthet Cécile Barnaud Nathalie Girard Julie Labatut Guillaume Martin 《Journal of Environmental Planning and Management》2016,59(2):280-301
Facing contemporary environmental crisis implies fostering agroecological innovations that take into account local ecological regulations and rely on multiple stakeholders' innovation capacities. This paper draws on two fields of literature that remain unconnected so far: participatory approaches and design sciences. It proposes an analysis grid to support a reflexive analysis of cases of implementation of three participatory design methods: ComMod (Companion Modelling for concerted management of natural resources), Forage Rummy (simulation-based board game for designing farming systems) and KCP (collective design workshops to foster innovation). This analysis highlights key features of the methods in view of agroecological innovation challenges, focusing on knowledge management and organisation for exploration. 相似文献