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951.
为研究不同楼梯类型的行人疏散效果,改进传统社会力模型,模拟4种常见梯形中行人的疏散过程,并通过总疏散时间和平均疏散速度指标以及微观速度密度分布图分析其疏散效果中存在的内在物理机制。研究表明:从安全和高效疏散角度上看,在限定空间中,单跑无平台梯形布局有利于低密度人群下人员的快速疏散;在中、高密度人群中,双分梯形的分流特点更有利于人员安全、快速疏散。从微观密度、速度分布图可看到这4种梯形在人员疏散过程中均易造成人员聚集拥堵,但发生事故风险的位置不同。单跑有、无平台梯形在楼梯上端和下端均易发生拥堵,且此时速度值大,发生事故的风险高;双分与双跑梯形在楼梯与平台的转角处易发生拥堵。 相似文献
952.
《International Journal of Sustainable Engineering》2013,6(3):199-207
Environmentally conscious product development, eco-design or design for environment is the methodology trying to introduce environmental requirements into product design. The first step of this process is the gathering of customer requirements for a structured product development procedure, such as quality function deployment (QFD). The problem is that environmental requirements are usually unspoken by the customers. This paper describes a methodology for uncovering such requirements by using environmental default questions in an elaboration process. This leads to an increased customer environmental awareness, and it generates a comprehensive list of requirements suitable for use in a subsequent QFD process. The effects of the elaboration process are demonstrated in one case study. 相似文献
953.
954.
结合Ⅱ类无烟煤的特点,分析探讨了针对低挥发分循环流化床20t/h无烟煤锅炉的节能设计,其中采用较高炉膛及较低空截面气速,在密相区布置合适数量的埋管受热面等环保技术措施。 相似文献
955.
以轴向支撑连接方式,利用自制的加热炉对约束钢梁进行了升—降温全过程的试验研究。重点研究了钢梁的跨中挠度随温度变化的规律,以及梁端不同轴向支撑刚度和钢柱不同轴压比条件下约束钢梁的屈曲模式及其梁端轴向支撑的破坏形态。基于ANSYS有限元软件,采用温度场和结构耦合中的间接法,对升-降温全过程中的约束钢梁进行了有限元分析。数值计算结果与试验结果吻合较好,验证了有限元模型和参数设置的合理性。根据对比分析,讨论了我国现行钢结构防火技术规范中存在的关键问题,特别提出了钢结构抗火设计应有的内涵,为钢结构抗火研究提供了新的思路。 相似文献
956.
《International Journal of Sustainable Engineering》2013,6(4):287-297
Research suggests that to allow for sustainable development, consumption patterns must be changed. Individual behaviour is central to society's impact on the environment. However, due to the complexity of environmental issues, much of the political debate and technology development is inaccessible to consumers and based on the values, interpretations and priorities of experts. User‐centred, user‐involved and participatory processes are fundamental in design disciplines such as interaction design and participatory design. Research into the possibilities for cross‐pollination of design for sustainability and user‐centred design has distinguished several strategies for design‐led behavioural change. The strategies differ with regard to the levels of control and responsibility that users are left with, ranging from empowerment through information about consequences of behaviour to blocking behaviour or forcing sustainable practices upon individuals. By considering technological behaviour‐steering strategies in the light of science and technology studies and theory on technological mediation, the paper addresses the ethical issues that arise and discusses how designers can contribute to more sustainable consumption patterns without compromising quality of life, individual freedom and democratic rights. 相似文献
957.
958.
《International Journal of Sustainable Engineering》2013,6(3):202-213
One of the key features of environmentally conscious manufacturing has been the efforts to promote product recycling and remanufacturing. Efficient material re‐utilisation through product disassembly to retrieve the desired parts and/or subassemblies is one rational approach. This is because it can promote the conservation of both material and energy resources whilst concurrently reducing environmental impact. However, because manufactured products may be made from many components, disassembly load becomes a critical factor that may obstruct the recovery of materials. Accordingly, it is essential to develop a practical method for deriving a disassembly plan to decrease such load, and to endow a certain value to the product at the end of its life cycle. With this understanding, the authors have developed a practical procedure to produce an adaptive disassembly strategy. The authors have applied a meta‐heuristic method known as genetic programming (GP) as a search engine to derive the adaptive disassembly sequence together with a multi‐objective optimisation method termed MOON2R. The authors have also proposed a hierarchical sequencing method to cope with large/complex products and added several ideas to increase the applicability associated with the interests in disassembly of hazardous and/or valuable parts, and alternative disassembly actions. Through numerical experiments, the authors examined the effectiveness of the proposed approach by showing its support for relevant planning and design decisions for product recycling and remanufacturing from various viewpoints. 相似文献
959.
《International Journal of Sustainable Engineering》2013,6(5):353-364
AbstractWith the advancements in technology and increase in demand for eco-efficient products, manufacturers are focusing on sustainable development of products. Enticing a huge demand over the recent years, sustainable development of Information and Communication Technology (ICT) products are a subject of interest for most practitioners and academicians. A number of factors are found to influence the sustainable development of ICT products. It is necessary to identify the most important factors and determine the dependencies of factors among themselves. In this regard, a case study has been conducted in the context of sustainable development of tablet devices. The most influential factors have been identified from literature and with experts input. The factor dependencies are established using Total Interpretive Structural Modelling (TISM) methodology. MICMAC analysis is used to classify the factors based on their ability to influence other factors. The output of TISM forms the input for MICMAC analysis. From the study, it was found that the factors, ‘Customer pressure’, ‘Government regulations’, ‘Competitiveness’, ‘Organization initiative’ and ‘Technological advancements’ are the most driving factors. Factors ‘Environmental impact’, ‘Energy efficiency’ and ‘Opportunities to upgrade’ were found to be dependent. 相似文献
960.
《International Journal of Sustainable Engineering》2013,6(3):163-172
To advance the area of design for sustainable behaviour (DfSB), a common behaviour terminology is needed to enable comparisons of studies across application areas. Thus, the map of pathways of sustainable behaviour was created with the aim of charting different paths that users can follow to reduce environmental impact when interacting with artefacts. The construction of the map results from a comparative analysis of sustainable behaviours identified in previous studies in conjunction with a review of existing behaviour classifications. The proposed map of pathways gives a comprehensive overview of all artefact-related resource-consuming usage behaviours, organised according to a design perspective and divided with regard to aspects of use and obtainment, primary and secondary artefact, duration and type of effort. Through design, the user can be encouraged to take any of the five identified paths: choice of artefact, changed use, maintenance and repair, mediated use and regulated artefact. Using the map in a DfSB process can guide the exploration phase and highlight potential design opportunities when choosing target behaviour. If adopted by the DfSB community, the united typology of the map also provides means necessary to make rigorous comparisons and develop the field and its tools. 相似文献