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21.
循环经济理论的国内外实践 总被引:45,自引:0,他引:45
循环经济理论是上个世纪末环境革命的产物。循环经济要求以“减量化(Reduce)、再使用(Reuse)、再循环(Recycle)”的3R原则为社会经济活动的准则。在发达国家,循环经济正在形成一股潮流与趋势,从物质层面、体制层面、价值层面全方位地改变着社会经济的运行。本文概略地介绍了循环经济的起源、内涵及国内外的成功实践,并介绍了我国生态工业园区的建设情况。 相似文献
22.
根据挤扩多盘桩桩土效应及土体极限承载力的理论分析和试验研究的成果,对挤扩多盘桩土体极限承载力的多种影响因素进行了定性或定量的分析,为进一步综合考虑各项因素进行挤扩多盘桩基础设计,提供了理论依据。 相似文献
23.
符五久 《东华理工学院学报》1994,(1):75-79
本文用电介质热力学理论导出了等压等容过程中,处在居里点附近的单电畴铁电体的热力学量.应用这些热力学量计算了由两个等温和两个等电压过程组成的铁电体循环的效率.结果表明,该循环的效率就是卡诺效率. 相似文献
24.
邱越 《武汉理工大学学报(社会科学版)》2005,18(3):410-416
运用产品生命周期理论详细分析了《楚天都市报》在导入期、成长期及成熟期三个不同发展阶段的创新作为。分析表明,在不同的发展阶段,媒体必须根据社会和市场的需求,找准定位,求索创新,才能在激烈的竞争中不断发展壮大。 相似文献
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26.
基于1980-2016年中国第一产业、第二产业(工业、建筑业)和第三产业的年度电力消费数据,采用H-P滤波技术对中国电力消费的趋势成分和波动成分轨迹进行刻画,运用马尔科夫区制转移[MS(n)-AR(p)]模型分析中国电力消费周期在各区制间的动态转移过程,识别改革开放以来中国电力消费周期的路径演化特征,在此基础上预测未来5年中国电力消费周期的区制分布情况。研究发现:(1)中国电力消费增长率的波动程度自2003年明显缩窄,且从2007年开始进入下行周期。(2)中国电力消费周期具有较强的稳定性,不易向着其收缩期和扩张期跨越。且中国电力消费处于"低速增长区制"的年份往往对应着中国经济发展相对趋缓的大环境。(3)2014-2015年中国电力消费向其收缩期转移的迹象明显,但预测结果表明,未来5年中国电力消费整体上将继续保持稳定增长的趋势。 相似文献
27.
Kathryn Nethercott 《Child & Family Social Work》2017,22(2):751-761
Legislation within England states that local authorities should provide services for all those families in need. However, research has identified that regardless of the introduction of strategies to identify need and enhance family support, ongoing barriers to services adhere. Taking a social constructionist approach, this study explored professionals' experiences of the use of the Common Assessment Framework form. Data were collected in four different local authorities in two phases. Forty‐one professionals from a variety of agencies took part in semi‐structured interviews. Data were analyzed thematically. Findings demonstrate that the professionals experienced difficulties in working through the Common Assessment Framework process, for example, in completing the form and engaging families. This situation led to the more experienced and knowledgeable professionals utilising creative ways to successfully navigate the ‘referral process’. Such creative working practices included the terminology used to complete the form and how the process was ‘sold’ to parents, so that they could be in a better position to engage parents and complete the Common Assessment Framework form. Because of this, more experienced professionals seem to be able to accelerate the referral process in order to access much needed support services for children and young people. 相似文献
28.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states. 相似文献
29.
剩余收益模型(Residual Income Model,RIM)是评估公司权益价值的经典模型,特别地,奥尔森系列剩余收益模型由于可以利用历史财务与会计数据而得到广泛运用。本文在一般剩余收益模型的基础上,运用规范研究、逻辑推理等方法,基于产品生命周期理论,即项目处于产品生命周期的不同阶段时,其净资产收益率不同,在增长期的净资产收益率持续上升,衰退期的净资产收益率持续下降,而成熟期的净资产收益率则围绕行业平均水平波动,从理论上就项目投资价值的评估构建了多阶段剩余收益项目决策模型,并就所构建的多阶段剩余收益项目决策模型进行参数赋值分析。研究结果表明该新构建的决策模型具有较好的理论和运用价值,可以作为一种有效的项目投资决策模型。本文的研究一是拓展了剩余收益模型的应用,从主要用于对公司权益价值的估值拓展至对项目投资决策的评估;二是有利于寻求项目投资决策的价值最大化。 相似文献
30.
Can Carbon Nanomaterials Improve CZTS Photovoltaic Devices? Evaluation of Performance and Impacts Using Integrated Life‐Cycle Assessment and Decision Analysis 下载免费PDF全文
In emergent photovoltaics, nanoscale materials hold promise for optimizing device characteristics; however, the related impacts remain uncertain, resulting in challenges to decisions on strategic investment in technology innovation. We integrate multi‐criteria decision analysis (MCDA) and life‐cycle assessment (LCA) results (LCA‐MCDA) as a method of incorporating values of a hypothetical federal acquisition manager into the assessment of risks and benefits of emerging photovoltaic materials. Specifically, we compare adoption of copper zinc tin sulfide (CZTS) devices with molybdenum back contacts to alternative devices employing graphite or graphene instead of molybdenum. LCA impact results are interpreted alongside benefits of substitution including cost reductions and performance improvements through application of multi‐attribute utility theory. To assess the role of uncertainty we apply Monte Carlo simulation and sensitivity analysis. We find that graphene or graphite back contacts outperform molybdenum under most scenarios and assumptions. The use of decision analysis clarifies potential advantages of adopting graphite as a back contact while emphasizing the importance of mitigating conventional impacts of graphene production processes if graphene is used in emerging CZTS devices. Our research further demonstrates that a combination of LCA and MCDA increases the usability of LCA in assessing product sustainability. In particular, this approach identifies the most influential assumptions and data gaps in the analysis and the areas in which either engineering controls or further data collection may be necessary. 相似文献