A design for EoL approach and metrics to favour closed-loop scenarios for products

Recently, environmentally conscious design and extended producer responsibility have become key aspects for companies that need to develop products that are sustainable along their whole life cycle. Design for End of Life (EoL) is a strategy that aims to reduce landfill waste through the implementation of closed-loop product life cycles. It is important to consider disassembly and EoL scenario management as early as the design phase. For these reasons, this paper presents an approach to help designers in the evaluation and subsequent improvement in product EoL performance. The method is based on four innovative EoL indices that compare different EoL scenarios for each product component. In this way, the designer can modify the product structure or the liaisons to maximise the reuse and remanufacture of components as well as material recycling. The presented case studies confirm the validity of the approach in helping designers during the redesign phase of goods and products to reduce the quantity of materials and industrial wastes sent to landfill.     

Should the fashion industry confront the sustainability challenge with 3D prototyping technology

Abstract

In this paper, coming out of a broader research project on how the digital prototype can be effectively integrated in the product development process of the clothing industry, the authors investigate the relationship between Corporate Social Responsibility (CSR) and Collective Actions on Sustainability and the environmental impact of the new model of fast and accelerating fashion. Extensive research was contacted with personal interviews and analysed primary data shows how new technology solutions like Product Lifecycle Management (PLM), 3D visualisation or 3D prototyping can work with and across supply chain partners to reduce the environmental footprint of their processes. The final phase of the paper involves the conceptualisation of a new apparel product development model, encompassing various digital tools which aim at addressing fit problems, extending the useful life of clothes and reducing the environmental impact of clothing in use through design and services.     

Integration of DFE and DFMA for the sustainable development of an automotive component

The recent developments in manufacturing organizations recognize sustainability as an important value addition for survival in the competitive scenario. The design engineers are in search of approaches for creating environmental conscious products. The purpose of this paper is to report a research carried out for ensuring sustainable product design by the integration of Design for Environment (DFE) and Design for Manufacture and Assembly (DFMA) methodologies. In this context, this paper reports a case study carried out in an automotive component. The candidate product is the charge alternator pulley. The existing pulley has been created using Computer Aided Design. Then sustainability analysis was conducted on the existing component for determining environmental impact. This is followed by the engineering analysis of the component using ANSYS. Then conceptual design changes were developed in the proposed product using DFMA concept. Then the environmental impact has been evaluated in terms of carbon footprint, energy consumption and air/water impacts on proposed product. It has been found that the optimized pulley design possesses minimal environmental impact. The result of the case study indicated that the integration of DFE and DFMA concept could initiate new developments in sustainable designs with minimal impact to the environment and it also reduces the product cost.     

Study on the initial velocity distribution of exhaled air from coughing and speaking

Increasing concerns about the spread of airborne pathogens such as severe acute respiratory syndrome (SARS) and novel swine-origin influenza A (H1N1) have attracted public attention to bioaerosols and protection against them. The airborne pathogens are likely to be expelled from coughing or speaking, so the physical data of the exhaled particles plays a key role in analyzing the pathway of airborne viruses. The objective of this study was to analyze the initial velocity and the angle of the exhaled airflow from coughing and speaking of 17 males and 9 females using Particle Image Velocimetry (PIV) and acrylic indoor chamber. The results showed that the average initial coughing velocity was 15.3 m/s for the males and 10.6 m/s for the females, while the average initial speaking velocity was 4.07 m/s and 2.31 m/s respectively. The angle of the exhaled air from coughing was around 38° for the males and 32° for the females, while that of the exhaled air from speaking was around 49° and 78° respectively. Also, the linear relation between the tested subject’s height and their coughing and speaking velocity was shown in this study.     

累积影响监测系统初步设计

累积影响监测和适应性管理是减少和改善累积影响评价不确定性的重要途径之一。文章初步探讨了累积影响监测的概念,提出了累积影响监测系统的设计原则,从内容、时空范围、监测指标、监测结果的表达、实施机构、实施程序等多方面对累积影响监测系统进行了初步探讨。     

Mitigation of operational failures via an economic framework of reliability,availability, and maintainability (RAM) during conceptual design

Abnormal process situation may lead to tremendous negative impact on sustainability, wellbeing of workers and adjacent communities, company's profit, and stability of supply chains. Failure of equipment and process subsystems are among the primary causes of abnormal situations. The conventional approach in handling failure-based abnormal situations has usually focused on operational strategies. Such an approach overlooks the critical role of process design in mitigating failure, while simultaneously considering the effects of such failure on process economic performance. The aim of this work is to introduce a systematic methodology that accounts for failure early enough during the conceptual design stages. Once a base-case design is developed, the methodology starts by identifying the sources of failure that are caused by reliability issues including equipment, operational procedures, and human errors for a given process system or subsystem. This allows for the identification of critical process subsystem(s) that are more failure-prone or cause greater downtime than other subsystems. Bayesian updating and Monte Carlo techniques are utilized to determine the appropriate distributions for the failure and repair scenario(s), respectively, in question. Markov analysis is used to determine the system availability. Next, the process revenue is described as a function of inherent availability. The effects of failures are incorporated into profitability calculations to establish an economic framework for trading off failure and profitability. In the proposed framework, the economic potential of alternative design scenarios is evaluated and an optimization formulation with the objective of maximizing incremental return on investment (IROI) is utilized to make a design decision. A case study on an ethylene plant is solved to demonstrate the applicability and value of the proposed approach.     

城市综合交通枢纽内消防“准安全区”设置原则和评估流程研究

由于使用功能的需要,综合交通枢纽中的交通换乘大厅常设计为高大空间结构。在实际工程中,该类高大空间建筑部位超出了现行防火规范关于防火分区面积和安全疏散距离的要求,通常采用性能化方法进行评估,在性能化评估中一般采用"准安全区"的理念。目前,"准安全区"的火灾安全仅依靠性能参数的比较论证,没有较为统一的设计准则。从不同的净空高度出发,综合考虑自然排烟口面积占地板面积的比例、相邻自然排烟口的间距和单个自然排烟口的面积等多种因素影响下的综合交通枢纽换乘大厅作为"准安全区"的设计要求,提出了"准安全区"设计原则和评估流程,研究成果可直接用于综合交通枢纽换乘大厅的设计与评估中,并对类似建筑具有指导意义。     

What humanlike errors do autonomous vehicles need to avoid to maximize safety?

Introduction: The final failure in the causal chain of events in 94% of crashes is driver error. It is assumed most crashes will be prevented by autonomous vehicles (AVs), but AVs will still crash if they make the same mistakes as humans. By identifying the distribution of crashes among various contributing factors, this study provides guidance on the roles AVs must perform and errors they must avoid to realize their safety potential. Method: Using the NMVCCS database, five categories of driver-related contributing factors were assigned to crashes: (1) sensing/perceiving (i.e., not recognizing hazards); (2) predicting (i.e., misjudging behavior of other vehicles); (3) planning/deciding (i.e., poor decision-making behind traffic law adherence and defensive driving); (4) execution/performance (i.e., inappropriate vehicle control); and (5) incapacitation (i.e., alcohol-impaired or otherwise incapacitated driver). Assuming AVs would have superior perception and be incapable of incapacitation, we determined how many crashes would persist beyond those with incapacitation or exclusively sensing/perceiving factors. Results: Thirty-three percent of crashes involved only sensing/perceiving factors (23%) or incapacitation (10%). If they could be prevented by AVs, 67% could remain, many with planning/deciding (41%), execution/performance (23%), and predicting (17%) factors. Crashes with planning/deciding factors often involved speeding (23%) or illegal maneuvers (15%). Conclusions: Errors in choosing evasive maneuvers, predicting actions of other road users, and traveling at speeds suitable for conditions will persist if designers program AVs to make errors similar to those of today’s human drivers. Planning/deciding factors, such as speeding and disobeying traffic laws, reflect driver preferences, and AV design philosophies will need to be consistent with safety rather than occupant preferences when they conflict. Practical applications: This study illustrates the complex roles AVs will have to perform and the risks arising from occupant preferences that AV designers and regulators must address if AVs will realize their potential to eliminate most crashes.     

A hybrid design methodology for structuring an Integrated Environmental Management System (IEMS) for shipping business

The International Safety Management (ISM) Code defines a broad framework for the safe management and operation of merchant ships, maintaining high standards of safety and environmental protection. On the other hand, ISO 14001:2004 provides a generic, worldwide environmental management standard that has been utilized by several industries. Both the ISM Code and ISO 14001:2004 have the practical goal of establishing a sustainable Integrated Environmental Management System (IEMS) for shipping businesses. This paper presents a hybrid design methodology that shows how requirements from both standards can be combined into a single execution scheme. Specifically, the Analytic Hierarchy Process (AHP) and Fuzzy Axiomatic Design (FAD) are used to structure an IEMS for ship management companies. This research provides decision aid to maritime executives in order to enhance the environmental performance in the shipping industry.     

The Controversy Over Natural Channel Design: Substantive Explanations and Potential Avenues for Resolution1

Lave, Rebecca, 2009. The Controversy Over Natural Channel Design: Substantive Explanations and Potential Avenues for Resolution. Journal of the American Water Resources Association (JAWRA) 45(6):1519‐1532. Abstract: The controversy over Natural Channel Design (NCD) has perplexed, and sometimes paralyzed, the stream restoration community in the United States for more than a decade. Despite the high level of energy expended by participants on both sides, the content of the discussion has not advanced significantly. The two sides seem to be talking past each other, rather than engaging in constructive conversation. This paper attempts to start that conversation. Based on five years of primarily social science research, this paper explains the key components of the NCD approach, evaluates a number of the most common objections raised by its critics, offers a brief explanation for the widespread use of NCD, and concludes with suggestions about how to bring the controversy to a close.