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831.
Abstract

In this article, the convective heat transfer coefficients of various agricultural products were investigated under open sun drying conditions. Data obtained from open sun drying experiments for eight agricultural products, namely, mulberry, strawberry, apple, garlic, potato, pumpkin, eggplant, and onion were used to determine values of convective heat transfer coefficient. The value of convective heat transfer coefficient was determined as 1.861 W/m2°C for mulberry, 6.691 W/m2°C for strawberry, 11.323 W/m2°C for apple, 1.136 W/m2°C for garlic, 8.224 W/m2°C for potato, 8.613 W/m2°C for pumpkin, 6.981 W/m2°C for eggplant, and 6.767 W/m2°C for onion. The experimental error in terms of percent uncertainty was also calculated.  相似文献   
832.
An appropriate logistics network is an important element of the infrastructure of any product recovery company. Small and medium enterprises (SMEs) constitute a major fraction of the product recovery industry with a different business objective and scale of operation from those of original equipment manufacturers. This paper addresses the network design issues for SMEs involved in product recovery activities. A mathematical formulation is presented in an SME context and a subsequent simulation model is developed. A genetic algorithm approach is presented for optimising the network for a single product scenario.  相似文献   
833.
This paper proposes an optimum system design method that especially considers product lifecycles and aims to help designers make effective decisions during the product design phase. By considering and estimating all lifecycle factors of cost and environmental impact in addition to the product performance, this method facilitates development of optimum design solutions that incorporate requirements pertaining to the product's entire lifecycle. Furthermore, quantitative estimation of lifecycle factors enables the numerical expression of optimum solutions, rather than depending primarily on experiment and designer intuition. To demonstrate the effectiveness of the proposed method, this paper develops an optimum system design method for a milling machine as an example of a machine product designed for long term use. The lifecycle cost and the lifecycle environmental impact are generally expressed as the summation of each value during manufacturing phase, usage phase, disposal phase and recycling phase. In this example model, Eco-indicator 99 is used to evaluate environmental impact. In the proposed lifecycle design optimisation method, the relationships among the product performance, the lifecycle cost and the lifecycle environmental impact are evaluated as a multi-objective optimisation problem. Analysis of the obtained Pareto optimum solution sets subsequently enables designers to pursue breakthrough product design solutions.  相似文献   
834.
Many businesses are recognising that environmental consciousness is an important concept for survival in today's highly competitive market. This paper presents a project in which quality function deployment (QFD) for environment (QFDE) has been applied to an Indian rotary switch manufacturing organisation to enable environmentally conscious design at the early stage of product development. QFDE consists of four phases. QFDE phases I and II are concerned with the identification of the rotary switch parts that are important in enhancing environmental consciousness. QFDE phases III and IV are concerned with the evaluation of the effect of design improvement on environmental quality requirements. The results obtained from the case study revealed that QFDE could be applied in the early stage of rotary switch product development as it identified the vital components from an environmental perspective and enabled the options for design improvement to be effectively evaluated. The managerial implications of the case study have also been presented.  相似文献   
835.
Recovery of used products has become a field of rapidly growing importance in reverse supply chain management. Product recovery includes collection, inspection/separation, disassembly, reconditioning/reuse, remanufacturing, and recycling. In real time situations, the collection of end‐of‐life (EoL) products from the customer and their return to the manufacturer is tedious and time consuming. Reduced product life cycles have increased the rate of product returns and disposals. Owing to shortened product economic life cycles, the recovery of value from EoL products is becoming a necessity. Companies have realised the value that they could recover by remanufacturing or recycling EoL products. Researchers have developed various models for product recovery network design, optimal inventory, production planning and control, remanufacturing, recycling, disposal, etc. The main purpose of this paper is to review the literature on EoL product recovery and inventory management issues in reverse supply chains and to outline some future directions for research on these issues.  相似文献   
836.
To slow down the increasing environmental degradation, design for sustainable behaviour (DfSB) has emerged in sustainable design aiming to promote behavioural change through design innovations to reduce environmental and social impacts from the demand side or consumer side. This paper presents a practice-based journey to investigate the process and results of the application of social-psychological theories into sustainable design. Focusing on the behaviour-related impacts of products and services during the use stage, a Design Behaviour Intervention Model (DBIM) is developed through the analysis and synthesis of the social-psychological theories and behaviour-changing strategies. The DBIM indicates that an in-depth study of consumer behaviour is the preliminary step in DfSB, which determines the application of design strategies and potentially the effectiveness of design interventions. A case study is presented to demonstrate the application of the model. The results show that consumer behaviour insights offer rich resources to assist designers in sustainable design innovation. Product-based design suggestions and a proposed solution highlight that the application of DBIM coupled with consumer involvement throughout the design process could produce desirable and sustainable patterns of household fridge use. Finally, the structured consideration of behavioural change and their possible application in DfSB are discussed.  相似文献   
837.
本文通过对济南市电磁辐射污染源、电磁辐射环境的调查、评价与分析 ,基本查清电磁辐射污染源的污染状况、布局以及对大环境的影响情况 ,初步得出济南市的电磁辐射环境基本是清洁的结论。  相似文献   
838.
极限与分配--再论环境法的本位   总被引:9,自引:0,他引:9  
环境问题是人类活动及其影响超出环境承受能力的极限所造成的后果。解决环境问题最根本的办法是分配,即把有限的环境资源在人类广泛的欲求之间做“相持而长”的分配。这种资源分配不同于收益分配,它体现的基本精神是义务。把体现义务精神的分配方法引入环境立法,必然导致环境法由传统的权利本位转变为义务本位。环境法不得不采用资源分配的办法,以义务为本位,这是由环境这种特殊的物质条件所决定的。  相似文献   
839.
以禾友化工有限公司清洁生产审计为例,根据市场的需要,适时的实施产品转型的策略,在提高资源的利用效率、降低生产成本和能耗、降污等方面产生明显的效果,进而提高了经济效益和环境效益。  相似文献   
840.
利用经济学上的“投入—产出”分析方法 ,结合气候变化对农业产量影响的计算机模拟系统 ,研究了当气候变化影响农业生产和产量时 ,江苏省农业产值的变化及与农业部门相联系的国民经济各个部门产出量的变化。考虑江苏省的经济发展速度和产业结构 ,预测了未来不同气候变化情景下 ,为使经济发展达到预期目标 ,社会需对各经济部门追加的资金投入量及各经济部门之间相互投入量的变化 ,提出了适应气候变化的相应对策。研究结果反映了国民经济各部门之间及部门与整体的相互联系 ,从而对制定区域经济平衡发展规划提供了理论依据和建议。  相似文献   
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