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101.
通过对压套零件的冲压工艺分析,省去外缘修边工序。外缘翻边时,利用板料的塑性平面各向异性在拉深件凸缘处产生的凸耳,翻边后形成图纸要求的凸、凹R50mm的外形尺寸,成功地用四套模具生产出摩托车离合器压套零件,降低了模具成本,提高了材料利用率。  相似文献   
102.
自行车D型中轴棍结构复杂,制造精度要求高。此文从材料选择、坯料制造、设备选型等方面阐述了D型中轴棍冷挤压成形工艺;对冷挤压模具结构及工作原理、凹模芯的设计及加工也做了详细介绍。  相似文献   
103.
Traditional approaches to the siting of potentially hazardous but regionally necessary facilities are often ineffective and lead to drawn-out legal disputes ultimately satisfactory to none of the parties. Research at MIT over the last decade has indicated five factors that may solve the siting puzzle. Application of these principles do not guarantee that a decision will not be disputed but may enhance the possibility of a wise and durable agreement.  相似文献   
104.
ABSTRACT

In 2009 the Desertec Industrial Initiative (DII) was founded by several, predominant German enterprises. The objective of DII was to organise the conditions for the realisation of the Desertec idea, which aimed to both (a) supply Europe, in a large-scale manner, with electricity produced in solar power plants in North Africa and the Arabic peninsula and (b) contribute to the self-supply of the Middle East North Africa region (MENA). Protagonists of the desert energy idea saw this megatechnic project as a starting point for a new trans-Mediterranean EU-MENA union, critics in contrast as a neo-colonial project. Disputes over the adequate interpretation and implementation of the Desertec idea broke out from the beginning. In 2014/2015, the media talked of the failure of DII and of the Desertec concept. The majority of the members left DII at the end of 2014. On the other hand, in some MENA countries renewables are playing a crucial role in securing the future of the energy sector. This paper analyses the development of DII and the Desertec idea by using concepts from Social Studies in Technology, and especially by the multi-level perspective approach in Transition Studies. It shows how the interplay of different factors, such as technological developments, entrepreneurial performances and political processes, lead to internal conflicts and the non-realisation – up to now – of related large-scale energy projects. As an important aspect of the paper, different understandings of the future of our energy supply and of North–South relations are presented in detail.  相似文献   
105.
膜技术在水处理中的应用前景   总被引:1,自引:0,他引:1  
介绍了膜分离技术的定义,种类,膜技术的应用领域及国内发展动态。  相似文献   
106.
气候变化对我国水文水资源系统的影响研究   总被引:2,自引:0,他引:2  
旨在介绍气候变化对我国水文水资源系统影响研究的进展、方法、技术及其优缺点,并分析气候变暖对我国水文水资源系统的影响结果,同时提出自己的一些建议。  相似文献   
107.
区域大气污染物总量控制技术与示范研究   总被引:7,自引:4,他引:3  
分析了我国的大气环境问题和特征,剖析了大气污染的成因;重点介绍了区域大气污染物总量控制技术研究中,大气污染物排放清单的编制技术,多尺度的空气质量模拟技术,基于现代控制理论的大气环境容量优化技术,基于环境容量和排放绩效的总量分配技术,多种总量监控方法,科学有效的总量控制管理机制和规则等的关键技术、技术突破、主要研究与理论创新及成果的应用与示范;紧密结合国家空气环境质量管理和大气污染控制的需要,提出了我国大气环境管理、政策和大气环境科学研究的建议.   相似文献   
108.
This essay examines the potential of Heidegger's phenomenology as a foundation for environmental communication theory, emphasizing his critiques of modern science, technology, humanism, and metaphysics. A phenomenological approach to environmental communication provides resources for recognizing metaphysical assumptions that endanger both humans and nature. The Hanford nuclear reservation serves as an illustrative text, exemplifying Heidegger's reading of nuclear energy as a culmination of both Western metaphysics and the instrumental stance that he calls “enframing.” In Heidegger's view, the ordering and control accomplished through enframing obscures the mutually constitutive relationship between humans and nature, and in doing so, diminishes the possibilities for authentic human existence. The chapter examines how both representational and constitutive models of communication contribute to those conditions, and adopts a set of concepts from Heidegger's phenomenology as a foundation for an alternative, “bounded constitutive” model.  相似文献   
109.
While it is widely known that sustainable development is the only sound and viable pathway for humankind’s future, its attainment remains elusive despite intensive efforts and some successes. The current industrial society approach based on product and process innovation in a variety of fields is not providing the expected results in addressing this important issue. In an attempt to carry out this unavoidable task, Osaka University’s Research Institute for Sustainability Science (RISS) introduces an integral and dynamic innovation system where technology plays a key role in fulfilling societal functions. This innovation system adopts a highly solution-driven approach that makes use of backcasting techniques based on long-term visions and mid-term strategic goals. Since technology management is the key to propelling effective innovation towards sustainability, we propose a technology transition management through the interaction of technology push, demand pull and institutional design, along with eight transition principles. RISS will develop this innovation system based on these three components and through the design of dynamic scenarios and their roadmaps.  相似文献   
110.
在阐述了阿特拉津的污染现状和危害基础上,探讨了国内外常规生物处理技术及深度处理:膜处理、高级氧化、催化还原、吸附等技术对阿特拉津的去除研究进展,并总结对比了各种处理技术的优缺点。  相似文献   
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