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621.
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   
622.
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   
623.
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   
624.
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   
625.
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   
626.
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   
627.
对于富水地层中深埋圆形巷道,为研究多种因素影响下巷道围岩塑性区范围和洞周位移的变化规律,对巷道围岩进行了弹塑性理论分析。对围岩应力场和渗流场进行耦合分析,基于统一强度理论和非关联流动法则,推导出多种因素影响下深埋圆形巷道围岩应力、位移和塑性区半径的解析计算式。结合工程实例进行计算分析,结果表明:中间主应力参数、围岩侧压系数、初始孔隙水压和剪胀角对围岩塑性区径向位移和塑性区范围均有显著影响,但影响规律各不相同;考虑中间主应力作用时,其他各因素的影响效应减弱。综合考虑以上各因素对围岩稳定性的影响,计算结果更加接近工程实际情况。  相似文献   
628.
分析了离子液体的脱氮原理,并按阴离子类型对其进行了分类,着重介绍了各类离子液体在油品非加氢脱氮中的应用。相对于其他非加氢脱氮技术,离子液体脱氮技术具有选择性高、化学及热稳定性高、操作工艺简单、易回收、污染少、脱氮率高等优点。进一步提高离子液体的重复使用性、稳定性、选择性和降低其生产成本是该领域今后研究工作的主要目标。  相似文献   
629.
The effects of feed strength, hydraulic residence time (HRT), and operational temperatures on soluble microbial product (SMP) production were investigated, to gain insights into the production mechanism. A carrier anaerobic baffled reactor (CABR) treating dilute wastewater was operated under a wide range of operational conditions, namely, feed strengths of 300-600 mg/L, HRTs of 9- 18 h, and temperatures of 10-28℃. Generally, SMP production increased with increasing feed strength and decreasing temperature. At high temperature (28℃), SMP production increased with decreasing HRT. As the temperature was decreased to 18 and 10℃, the SMP production was at its peak for 12 h HRT. Therefore, temperature could be an important determinant of SMP production along with HRT. A higher SMP to soluble chemical oxygen demand (SCOD) ratio was found at high temperature and long HRT because of complete volatile fatty acid degradation. SMP accounted for 50%-75% of the SCOD in the last chamber of the CABR. As a secondary metabolite, some SMP could be consumed at lower feed strength.  相似文献   
630.
综合考虑舰船装备系统的复杂性和海洋环境的严酷性,提出了一种基于关键产品把控的舰船装备环境适应性设计对策分析方法.该方法在分析装备环境适应性设计基本要求的基础上,提出了按产品层次逐级进行环境适应性分析,根据其对上一级产品或整个装备系统功能的影响,层层剥离出环境适应性关键产品,通过识别环境适应性薄弱环节,消除环境适应性风险或隐患,建立了环境适应性设计关注点、环境要求、影响因素、薄弱环节、控制措施、具体方法等之间的映射关系,形成了环境适应性设计解决对策,建立了基于关键产品把控的舰船装备环境适应性设计对策分析方法,给出了方法应用示例.该方法为舰船以及其他装备开展环境适应性设计提供了一种可行的借鉴方法.  相似文献   
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