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‘Design for Remanufacture’ or DfRem, is an area of remanufacturing research that has received relatively high levels of interest in recent years, due to the recognition that a product’s design may have a high impact on remanufacturing efficiency. However, the overall volume of literature dedicated to DfRem is low and there is still much to learn about the subject. The purpose of this literature review is to collate the current body of literature and establish a contemporary understanding of DfRem through analysing the trends, agreements and conflicts of opinion in the field. Much of the DfRem literature to date is focused upon the investigation of remanufacturing problems associated with product design, and the subsequent development of design methods and tools, either specifically developed to aid DfRem or as adaptations of existing design methods. These methods and tools vary in purpose and intended use but all largely remain within the academic realm to date. Within the literature there is widespread agreement that any approach to DfRem must consider both product and process, yet the ‘design for X’ definition of the task continues to spark debate. The key problems and issues that future DfRem research should address have been identified in this paper, from both within the literature and from the current gaps in the literature. Some key recommendations for future research include the need for ‘lifecycle thinking’ within design method development and the need for greater exploration into the organisational factors affecting DfRem integration into the design process, from the perspectives of the OEM and designer.  相似文献   

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粮食与营养安全研究评述及展望   总被引:1,自引:0,他引:1  
当前国际粮食安全局势堪忧,大多数发展中国家饥饿、营养素缺乏与营养过剩三重困境并存,实现全球粮食安全与营养安全的双重目标任重道远。本文梳理了95篇文献,旨在理清粮食与营养安全的发展脉络及演变规律,提出中国未来粮食与营养安全的研究重点。首先对全球粮食与营养安全的概念演变进行回顾,指出粮食安全概念由谷物供给总量安全到所有食物数量安全、再到食物质量与营养安全与可持续内涵的动态演化,由单一可供应维度向可供应、可获得性、可利用性、稳定性、可持续性多维度不断拓展。随后,从宏观国家层面梳理中国粮食与营养需求分析及预测、粮食生产能力和进口能力的相关研究,从微观家庭及个人层面评述收入、市场、城镇化、农户农业生产对食物消费及营养的影响。最后,基于未来城乡居民营养均衡发展目标,对中国粮食与营养安全研究的主要趋势和未来研究重点作出展望,指出未来展开对农业生产多样性、作物种植结构调整及作物营养强化,城镇化与市场建设的影响,城市中低收入人群和农村贫困人口营养问题的研究具有重大意义。  相似文献   

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Under the Clean Water Act (CWA), the EPA is responsible for protecting the chemical, physical, and biological integrity of the nation’s waters. Toxic contaminants in bottom sediments of the nation’s lakes, rivers, wetlands and coastal water create the potential for continued environmental degradation, even where water column contaminant levels comply with established water quality criteria. In response, EPA has developed an Agency-wide Contaminated Sediment Strategy to address the problem of contaminated sediments. One key feature of this strategy is the development of Sediment Quality Guidelines (SQGs). SQGs would be used to assess the extent of sediment contamination, or to implement measures designed to limit or prevent additional contamination. A number of specific technical approaches for the development of SQGs that are based on theoretical and empirical foundations have been proposed, including effects-based correlative approaches, equilibrium partitioning, and consensus using a combination of approaches. While each have their own advantages and limitations, any SQG must consider the bio-availability of contaminants in the sediment and the ecological realism associated with the implementation. Therefore, it is clear that the implementation of any SQG will incorporate biological testing. Based on the current state of the science, EPA will likely proceed with the establishment of formal SQGs which will rely heavily on the equilibrium partitioning (EqP) approach. There are a number of significant research needs that will need to be addressed as the EqP approach is implemented, including sediment quality modeling, sediment toxicity identification evaluations, studies that address bio-availability, studies that address the relative importance of exposure via sediment ingestion or ingestion of contaminated benthos, toxicological demonstrations of applicability of any SQGs, field verification, extension of the non-ionic mixture models to non-PAH compounds, and the establishment of toxicological databases (with benthic organisms) for standard toxicity endpoints.  相似文献   

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再制造工程是一种末端产品的资源化利用方式。阐述了再制造工程的内涵、在全生命周期中的地位及国内外发展现状,分析了再制造所能够带来的巨大的资源效益、经济效益、社会效益和环境效益,得出结论:再制造工程是末端产品进行资源化处理的最佳利用方式。  相似文献   

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In this overview the current knowledge of the relationship between an increased nuchal translucency (NT) measurement and fetal heart structure and function in chromosomally normal fetuses is reviewed. Relevant pathophysiological theories behind the increased NT are discussed. Fetuses with an increased NT have an increased risk for congenital heart disease (CHD) with no particular bias for one form of CHD over another. This risk increases with increasing NT measurement. Although the NT measurement is only a modestly effective screening tool for all CHD when used alone, it may indeed be effective in identifying specific CHD “likely to benefit” from prenatal diagnosis. The combination of an increased NT, tricuspid regurgitation and an abnormal ductus venosus (DV) Doppler flow profile, is a strong marker for CHD. A fetal echocardiogram should be performed at 20 weeks' gestation in fetuses with an NT ≥ 95th percentile but < 99th percentile. When the NT measurement is ≥ 99th percentile, or when tricuspid regurgitation and/or an abnormal DV flow pattern is found along with the increased NT, an earlier echocardiogram is indicated, followed by a repeat scan at around 20 weeks' gestation. The resultant increased demand for early fetal echocardiography and sonographers with this special expertise needs to be planned and provided for. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

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This report reviews the literature of sequential or within-event precipitation sampler construction and includes a limited survey of their applications. Collection apparatus have been classified as manually segmenting samplers, linked collection vessels, automatically segmenting samplers and continuous monitors (Robertson et. al., U.S. EPA Report, 1980). Design criteria for an ideal collector are discussed.  相似文献   

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2016 marked the 25th anniversary of the Protocol on Environmental Protection to the Antarctic Treaty. Terrestrial ice-free areas constitute approximately 0.18% of Antarctica, but represent the most biologically active, historically rich, and environmentally sensitive sites. Antarctic soils are easily disturbed and environmental legacies of human activities are scattered across the continent; many are remnants of the 1950s-1980s when environmental protection was less comprehensive than today. Adoption of the Environmental Protocol in 1991 represented an important and proactive shift in Antarctic governance, securing environmental protection as a fundamental tenet of the Treaty System. Twenty five years on standards of environmental management have greatly improved, yet environmental pressures are compounding. Shortcomings in the implementation of the Environmental Protocol exist due to disparities in cultural values, operational realities, and inconsistent environmental impact assessments among governments and National Antarctic Programs. Non-native species management remains underdeveloped; and there is inadequate representation of all biogeographic regions within the Protected Area system; therefore jeopardizing conservation of Antarctic biodiversity and the integrity of the soil environment. Fundamental improvements are required to address the current shortcomings and ensure effective environmental protection for the next 25 years, including: (1) increased multinational and multidisciplinary collaboration to answer targeted research questions addressing contemporary management challenges, (2) effective communication of science to policy makers and environmental managers to inform decision- making, and (3) making the mandate of long-term monitoring of the terrestrial environment a high priority for all governments signatory to the Antarctic Treaty.  相似文献   

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频繁的千年尺度气候波动是冰期气候的典型特征.末次冰期时,南极和格陵兰在千年尺度呈现出反相位的温度变化:当格陵兰气候处于暖期时南极缓慢降温,当格陵兰处于冷期时南极缓慢升温.这种南北极遥相关现象被称为Bipolar Seesaw.Bipolar Seesaw对气候的影响是全球性的,并且Bipolar Seesaw背后的物理...  相似文献   

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1 IntroductionDuringthepastfewyears,membraneseparationshavebecomemorewidelyused,andreplacedsomeoftheconventionalconcentrationt?..  相似文献   

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We report a case of severe Clostridium welchii infection following amniocentesis with septicaemia, haemolysis, DIC, pulmonary oedema and renal failure. Full recovery occurred following aggressive conservative management using antibiotics, endometrial curettage and intensive monitoring. The patient retained her uterus and had a successful pregnancy two years later although caesarean section for uterine rupture was required. Conservative management with conservation of the uterus and ovaries may be a safe and effective option in the management of severe Clostridium infections, using antibiotics, endometrial curettage and multidisciplinary team input. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

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The concept of innovation has been used in a wide range of contexts and the theoretical development has proven to be extremely valuable to provide important insights into intra-market competition, strategy and regulatory policy. The automotive industry offers a fertile terrain for progress of the uncompleted theory building process of innovation, especially with the introduction of alternative fuels and alternative powertrain technologies.This paper investigates the concept of innovation in the context of the modern automotive industry, by focusing on the notion of regulatory innovation of alternative fuels and alternative powertrain technologies. For the purpose of analysing this issue, special attention is given to the concepts of radical and incremental innovation, which are applied to existing alternative fuels and alternative powertrain technologies, including hybrids, biofuels and hydrogen power. The article explores these three categories looking at representative case studies: the Brazilian ethanol experience with biofuels, the development of the Toyota hybrid vehicle and the technological development of hydrogen fuel cells. These categories have been selected because they represent the most important advances in cleaner production for the automotive industry.  相似文献   

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Advanced paternal age (APA) is associated with infertility and other reproductive risks. Studies looking at APA and outcomes have used different paternal age cut-offs, which has complicated systematic evaluations of reproductive risk associated with paternal aging. This review of the literature suggests that the impact of paternal aging on adverse reproductive outcomes is small, but significant. Studies suggest the incidence of paternal age effect disorders attributed to de novo autosomal dominant mutations is less than 0.5%. Other risks associated with APA include infertility, miscarriage, birth defects, poor neurodevelopmental outcomes, and childhood cancer. Although the increasing prevalence of APA has mirrored the rise in maternal age, this topic has not received similar attention. In this review, we summarize the available literature on the reproductive risks associated with APA to provide a framework for comprehensive genetic counseling and evidence-based management of APA pregnancies.  相似文献   

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