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991.
In this work, design for environment (DfE) methodologies have been used as a tool for the development of a more sustainable supply chain. In particular by combining life‐cycle assessment (LCA) techniques and by using the quality function deployment (QFD) multi‐criteria matrices, an ‘environmental compromise’ can be reached. In this work, the QFD matrices have been developed in a new way using an iterative process that involves the whole supply chain starting from the product life‐cycle, taking into consideration the machines that make the product and their components. This methodology is compatible with the requirements of the various stakeholders, suppliers, manufacturers and clients, involved in the supply chain. To assess the validity of the proposed approach a specific supply chain was studied concerning packaging systems for liquid food substances (beverage cartons). Firstly all the stages which are most critical from the environmental point of view in the supply chain of packaging systems were identified and assessed. The starting point for the analysis of environmental aspects and impacts which characterise the supply chain was LCA, which proved to be useful for the identification and the environmental assessment of the various stages in a packaging system. Through the use of ‘iterative QFD’ it is possible to arrive at a definition of the engineering characteristics of all the machinery which is involved in the supply chain. In particular in this work the authors have tried to identify the critical points in the design of those machines which either make the beverage cartons or are involved in the filling process.  相似文献   
992.
Construction practices tend to have an adverse impact on the environment through their contribution to CO2 emission, increased waste and energy consumption. The United Arab Emirates (UAE) has launched many initiatives to encourage green design over the past years and to work towards a sustainable community. Nonetheless, such initiatives require a considerable amount of time to penetrate the professional psyche and showcase real results that are easily utilised by the construction community. The aim of this research was to study the current degree of use of Green Design Parameters (GDPs) in the UAE construction projects and to identify the main constraints that hinder their application. To achieve the study's objective, a survey was designed and distributed to engineering design professionals in different consulting and contracting companies in the seven emirates of the UAE. Feedback from 112 projects was examined and statistically analysed. The analysis showed a degree of awareness and use of some key GDPs. Moreover, the data showed no correlation between the degree of using GDPs in a project and its cost and schedule. Not surprisingly, the lack of knowledge about green parameters and the lack of trust in recycled materials are the main constraints that featured in the responses.  相似文献   
993.
The pharmaceutical industry traditionally uses complex batch-type processes in the manufacture of medicines, although the production of specific medicines by continuous processes is currently envisaged. Due to the diversity of these processes, it is difficult to define a general set of waste prevention guidelines that would apply to all drug manufacturing. The most applicable methods of prevention can, however, be delineated for each of the five steps in the pharmaceutical manufacturing, i.e. (i) research and development, (ii) chemical synthesis, (iii) natural product extraction, (iv) fermentation and (v) product formulation. Waste streams generally arise from cleaning and sterilising equipment, chemical spills, rejected by-products and the processes themselves. Prevention mainly involves waste reduction by materials substitution, process modification/optimisation, waste stream segregation and solvent waste recycling. These measures are assessed and lead to guidelines for waste minimisation methods according to the waste streams under scrutiny.  相似文献   
994.
Traditional research into sustainable design has typically focused on reducing the environmental impact of products during the manufacture and disposal stages of a products' lifecycle. The last decade, however, has seen an explosion of research into understanding and moderating user behaviour during the use phase of a products' lifecycle; often the most resource-intensive phase. One of the biggest factors that affects behaviour is a users cultural context; however, the effect of cultural context on design for sustainable behaviour has had little exploration in this relatively new research field.  相似文献   
995.
Design for Sustainable Behaviour (DfSB) is a maturing research area concerned with the application of design strategies to influence consumer behaviour during a products use phase towards more sustainable action. However, current DfSB research has focussed on strategy selection with little research into understanding the real-world impact of the behaviour changing interventions debated. This article presents the results of an extensive literature review of one specific DfSB strategy, feedback – a user agentive performance indicator. These findings exemplify the considerations and limitations of this particular approach to behaviour change, drawing on empirical research conducted by a breadth of authors, including two of the only medium-term case studies in the field of DfSB. Considerations discussed include the frequency, duration and accuracy of feedback; the selection of metrics and the presentation medium and mode; the use of ambience and the location of the installation. Limitations of feedback include the need for additional information and comparisons; the issue with multiple users; technical issues; relegation to background technology and the potential rebound effects. This article provides insights to both improve the effectiveness of future feedback design efforts and also to help facilitate discussion on feedbacks position as a strategy within DfSB.  相似文献   
996.
基于气旋分离和滤筒过滤的除尘原理,采用气旋分离作为一级除尘分离大颗粒粉尘,滤筒过滤作为二级除尘去除细颗粒物,设计并构建了适用于抛光打磨车间的便携式除尘器试验模型,并对其运行性能参数进行测试。结果表明:除尘器处理风量为117~179 m3/h,漏风率和设备阻力随处理风量的增加而升高,漏风率控制在3.52%以内,设备阻力最小为163 Pa,最大为393 Pa;除尘效率随风量的增大而发生轻微降低,该便携式除尘器的最高除尘效率达99.63%。  相似文献   
997.
In order to facilitate water resources decisions, it is important that accurate and informative hydrometric data are collected. Combining information theory with multi‐objective optimization has led to methods of optimizing the information content provided by hydrometric networks; however, there is no available study on the effects of spatial scale and data limitation on these methods. Herein, a dual entropy multi‐objective optimization (DEMO) and a transinformation (TI) analysis were done to recommend optimal locations for additional hydrometric stations in the Madawaska Watershed. This analysis was designed to be comparative to a similar study conducted on the Ottawa River Basin which encompasses the Madawaska Watershed to allow for an investigation of the spatial scale effects in this type of network design. This study concludes that TI analysis is not adversely affected by scaling; however, the DEMO analysis is sensitive to the placement of potential station locations and the size of the study area. This study also examines the benefit of including nearby stations when the area of interest does not have a sufficient number of existing hydrometric stations for analysis. It is shown that these stations can provide useful information because their inclusion in the analysis increased the average TI in the watershed. Recommendations were made as to the ideal locations of additional stations in the Madawaska Watershed hydrometric network.  相似文献   
998.
The aim of this paper is to inform urban design practice through deeper understanding and analysis of the social dynamics of public outdoor space in ethnically diverse neighbourhoods. We hypothesise that findings from ethnographic research can provide a resource that improves cultural literacy and supports social justice in professional practice. The primary method is a meta-synthesis literature review of 24 ethnographic research papers, all of which explore some dimensions of public open space use and values in UK urban contexts characterised by ethnic and racial diversity. We summarise thematic understandings and significance of neighbourhood places of shared activity, parks, spaces of passing-by and of retreat. We evaluate the implications for intercultural social dynamics, exploring the spatial and temporal dimensions of conviviality and racism in public open space. We then argue that it is possible to develop principles for urban design practice informed by this work, and propose four for discussion: maximising straightforward participation, legitimising diversity of activity, designing in micro-retreats of nearby quietness and addressing structural inequalities of open space provision. We conclude that ethnographic research can provide detailed insights into the use of the public realm and also inform a more nuanced understanding of outdoor sociality relevant for an increasingly diverse society. The challenge is two-fold: for ethnographers to become less cautious in engaging with decisions and priorities regarding how cities change, and for urban designers to explicitly embed informed understandings of difference into their broad desire for inclusive public space.  相似文献   
999.
An axial symmetry augmented vertical axis wind turbine, which is suitable for arbitrary wind directions, is proposed in this paper. In order to improve the power generation ability of the S-type vertical axis wind turbine, a set of so-called “collection-shield boards” are installed symmetrically around the rotating S-type rotor. The flow fields around this type of wind turbine are numerically simulated with the aid of CFD method. The optimized design of geometrical parameters of the rotor and collection-shield boards is conducted by using the orthogonal design method. The obtained results suggest that the power output of the optimized augmented wind turbine can reach nearly three times higher than that of the conventional S-type vertical axis wind turbine.  相似文献   
1000.
本研究以无锡市A~2O-MBR(Anaeroxic Anoxic Oxic-Membrane Bio-Reactor,A~2O-MBR)工艺、CAST(Cyclic Activated Sludge System,CAST)工艺和氧化沟工艺3种不同工艺的污泥泥质为对象,通过试验测定7种污泥泥质参数,分析不同污泥泥质参数间相关性.并通过主成分分析发现含固率、胞外聚合物(Extracellular Polymeric Substances,EPS)蛋白质和多糖是影响污泥脱水性能的主要因素.通过均匀设计实验探究不同药剂投配比对污泥毛细吸水时间及有机物含量的影响,并采用统计分析软件(Statistical Product and Service Solutions,SPSS)构建污泥脱水药剂线性回归模型,得到线性方程:含固率=2.5049-0.0261X_1-2.28×10~(-3)X_2;有机物=40.5728-0.1894X_1+0.2264X_2.通过验证试验发现,此线性方程残差低于3.0,可用于指导实际工程中药剂投配比.  相似文献   
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