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971.
《International Journal of Sustainable Engineering》2013,6(4):250-260
Reverse logistics play a significantly increased role in supply chains. Producers are incorporating reverse logistics into their supply chain design because of governmental legislation, economic benefits from product recovery, and customers' demands for better environmental practices. Motivated producers face two main challenges in reverse logistics network design: (1) how do you build product recovery activities into traditional forward logistics networks? and (2) how do you manage the impact of uncertainty in the reverse logistics supply chain? Moreover, producers need to consider many tradeoffs leading to efficient network design. Published case studies have discussed these tradeoffs, and we describe a framework to evaluate these tradeoff considerations. We then apply the framework to three new case studies: medical device refurbishing, municipal e‐waste recycling, and carpet fibre recycling. 相似文献
972.
《International Journal of Sustainable Engineering》2013,6(1):16-23
Traditional supply chain design is merely based on the open loop or forward flow of materials, neglecting reverse flow for recovery of materials despite the recent concerns of customers and governments about environmental and production cost reductions. New supply chain design should be closed loop which implements traditional supply chain concepts with reverse flow or a material recovery system to reduce production cost and enhance customer satisfaction about environmental consciousness and to meet legal requirements. In our research, we designed a closed-loop supply chain which consists of recovery options such as collection centres and remanufacturing plants (reverse flow) in addition to traditional supply chain tiers (forward flow), and tried to find the best location for these facilities in a discrete space based on decision makers' opinions. Since there are uncertainties about decision parameters in an uncapacitated facility location problem, we implemented the fuzzy TOPSIS method to solve the location decision problem and find the best place to locate a remanufacturing facility. 相似文献
973.
《International Journal of Sustainable Engineering》2013,6(3):236-250
Over the last three decades, new concepts, strategies, frameworks and systems have been developed to tackle the sustainable development issue. This paper reviews the challenges, perspectives and recent advances in support of sustainable production operations decision-making. The aim of this review is to provide a holistic understanding of advanced scientific analysis methodologies for the evaluation of sustainability, to provide efficient decision support. Over 100 publications have been analysed, and a characterisation of state-of-the-art sustainability analysis methodologies has been produced, which includes life cycle assessment and multi-criteria decision analysis (MCDA), along with their applications to three key areas of production operations: sustainable design, sustainable manufacture and sustainable supply chain management. Distribution of existing work is discussed and future research directions are elicited from the literature. The paper finds three trends in supporting sustainable production operations decisions: (a) sustainability analysis has moved to whole life cycle assessment from single-stage assessment, (b) sustainability analysis has shifted away from single criterion to MCDA and (c) sustainability analysis has evolved from stand-alone approaches to integrated systematic methodologies. The paper concludes that integrated sustainability analysis can provide more efficient and effective support to complex decision-making in sustainable production operations. 相似文献
974.
基于差异进化支持向量机的坑外土体沉降预测 总被引:1,自引:0,他引:1
就用支持向量机(SVM)预测基坑外土体沉降而言,通过差异进化(DE)算法构造适合的决策函数十分重要。在确定坑外土体沉降函数的基本形式下,进行参数反演。后将得到的解析式作为SVM的决策函数,再进行核函数转换,从而使SVM的曲线拟合更加快速,预测更加准确。对大连地铁湾家车站基坑坑外土体的沉降数据的分析及预测的结果表明,使用SVM-DE算法在计算数据量、计算消耗时间和预测精度方面优于2种方法单独使用。 相似文献
975.
新型带弹簧支撑抗冲击研究及其在泥石流拦挡坝中的应用 总被引:1,自引:0,他引:1
为了使结构或构件能够更好地承受住泥石流、爆炸等冲击荷载,设计出一种新型带弹簧的支撑(件)。运用显式动力分析方法,对冲击载荷作用下的这种支撑进行数值模拟,计算得到新型支撑的动力响应,并与普通支撑进行对比分析。结果表明,新型支撑能更好地防止冲击荷载作用下的结构过早发生塑性变形。另外,在泥石流防治结构中,引入这种新型支撑,设计出新型泥石流拦挡坝。运用有限元软件ls-dyna对新型泥石流拦挡坝进行大块石冲击模拟,并与普通重力式拦挡坝进行对比分析,得出新型拦挡坝坝底应力远小于普通泥石流拦挡坝的应力。研究结果表明,新型带弹簧支撑及新型泥石流拦挡坝的抗冲击效果非常明显。 相似文献
976.
The extent of wetland in New Zealand has decreased by approximately 90% since European settlement began in 1840. Remaining
wetlands continue to be threatened by drainage, weeds, and pest invasion. This article presents a rapid method for broad-scale
mapping and prioritising palustrine and estuarine wetlands for conservation. Classes of wetland (lacustrine, estuarine, riverine,
marine, and palustrine) were mapped using Landsat ETM+ imagery and centre-points of palustrine and estuarine sites as ancillary
data. The results shown are for the Manawatu–Wanganui region, which was found to have 3060 ha of palustrine and 250 ha of
estuarine wetlands. To set conservation priorities, landscape indicators were computed from a land-cover map and a digital
terrain model. Four global indicators were used (representativeness, area, surrounding naturalness, and connectivity), and
each was assigned a value to score wetland sites in the region. The final score is an additive function that weights the relative
importance of each indicator (i.e., multicriteria decision analysis). The whole process of mapping and ranking wetlands in
the Manawatu–Wanganui region took only 6 weeks. The rapid methodology means that consistent wetland inventories and ranking
can now actually be produced at reasonable cost, and conservation resources may therefore be better targeted. With complete
inventories and priority lists of wetlands, managers will be able to plan for conservation without having to wait for the
collection of detailed biologic information, which may now also be prioritised. 相似文献
977.
针对煤层瓦斯含量与其影响因素之间存在着复杂的非线性关系,建立了基于主成分分析和支持向量回归机的煤层瓦斯含量预测模型。该模型有效地解决了小样本、非线性预测的问题,并发挥了主成分分析法消除输入变量间相关性的优点,减少了输入变量个数,提高了预测精度和收敛速度。通过实证分析,该模型的预测精度高,能够直接用于煤矿现场预测煤层瓦斯含量。 相似文献
978.
王成武 《中国安全科学学报》2011,21(4)
为对室内轰燃进行准确预测,针对室内轰燃样本的不足在一定程度上制约了其应用,为此运用SVM技术构建室内轰燃预测的数学模型。在小样本条件下,应用工具软件LIBSVM进行仿真,并将SVM模型预测结果和人工神经网络预测结果进行对比。结果显示,SVM技术能较好地解决小样本和模型预测精确度之间的矛盾,SVM模型其预测精度及可行性高于神经网络模型。实例表明,由于室内火灾受多种因素影响,传统的预测方法存在一定的局限性,而SVM模型预测法预测的结果与试验结果比较一致。 相似文献
979.
为修订中国大陆《职业病目录》提供参考意见,通过循证决策分析,比较中国香港特别行政区职业病名单和中国大陆《职业病目录》的异同点和优劣势,探讨香港职业病名单制度实践经验。结果表明,两地职业病名单在立法程序、地位与作用、分类方法存在一致性,在列举方式、法律依据、制定机构、分类及覆盖范围方面有所不同。特别是中国大陆生物因素所致职业病及职业性肌肉骨骼疾病覆盖范围较窄。在修订《职业病目录》时,应根据社会经济发展需求,结合社会保障能力,逐渐扩大职业病覆盖范围,以适应职业病防治工作的需求。 相似文献
980.
周伟兴 《中国安全生产科学技术》2012,8(8):205-208
简单介绍了海洋石油多功能支持平台的基本情况,总结了多功能支持平台现有的三种安全管理工具,分别是工作许可证、工作安全风险分析(JSA)和"五想五不干"行为安全观察卡;同时结合海洋石油多功能支持平台自身特点,分析了如何做好平台的安全教育培训、安全检查和班组安全建设以及应急演练等安全管理工作;通过增强全员的安全意识、及时消除事故隐患及增强基层的安全管理和加强平台的应急反应能力,提高海洋石油多功能支持平台的安全管理水平,以期达到海洋石油平台安全、健康、和谐发展的目的,可供同行借鉴和参考。 相似文献