Search results

The paper presents an efficient methodology that was developed for the reliability prediction and the failure mode effects and criticality analysis (FMECA) of electronic devices using fuzzy logic.

The reliability prediction is based on the general features and characteristics of the MIL‐HDBK‐217FN2 technical document and a derating plan for the system design is developed in order to maintain low components’ failure rates. These failure rates are used in the FMECA, which uses fuzzy sets to represent the respective parameters. A fuzzy failure mode risk index is introduced that gives priority to the criticality of the components for the system operation, while a knowledge base is developed to identify the rules governing the fuzzy inputs and output. The fuzzy inference module is Mamdani type and uses the min‐max implication‐aggregation.

A typical power electronic device such as a switched mode power supply was analyzed and the appropriate reliability indices were estimated using the stress factors of the derating plan. The fuzzy failure mode risk indices were calculated and compared with the respective indices calculated by the conventional FMECA.

Further research efforts are needed for the application of fuzzy modeling techniques in the area of reliability assessment of electronic devices. These research efforts can be concentrated in certain applications that have practical value.

Practical applications can use a fuzzy FMECA modeling instead of the classical FMECA one, in order to obtain a more accurate analysis.

Fuzzy modeling of FMECA is described which can calculate fuzzy failure mode risk indices.

In electronics assembly, the losses of electronic components throughout the surface‐mounting process (including kitting and setup) are hard to trace. This affects accurate material planning and manufacturing costing. This paper aims to investigate this issue and to generate a suitable mixture of strategies for the relevant causes.

The project is executed by an undergraduate manufacturing engineering student and several company engineers over a period of ten weeks. Define, measure, analyze, improve, and control (DMAIC) approach delineates the project stages. The solutions devised must be in agreement with lean philosophies and practices currently upheld in the company.

Component losses stem from multiple sources and are complicated by inherent information inaccuracies. A right mixture of strategies is envisaged on analysis on these sources. An average 18 percent of decrement in component losses in monetary value is achieved in the initial 16 weeks of the improvement phase.

The DMAIC approach induces a focused, systematic and thorough study on the selected area. For the limitations, this study is based on a single industrial case. The evidence may be anecdotal and idiosyncratic to the electronics assembly industry. The final solutions which emerged need to factor in the organization current maturities in Lean and Six Sigma concepts.

Component loss is a common problem faced by electronics assembly industries. In this paper, the nature of the problem and the related investigation are extensively illustrated in the context of the case study. As many electronics assembly industries have embarked on Lean or Lean Six Sigma journeys, the savings and data accuracy improvement achieved in this case study provide valuable benchmarks.

The issues related to electronic component losses have not been reported in established literature to date. This is also the first reported success case study of applying DMAIC to address these issues in a lean company.

The global electronic equipment industry has evolved into one of the most innovative technology-based business sectors to transpire in the last three decades. Much of its success has been attributed to effective supply chain management. The purpose of this paper is to provide an examination of external risk factors associated with the industry’s key suppliers through the creation of Bayesian networks which can be used to benchmark external risks among these suppliers.

The study sample consists of the suppliers to seven of the leading global electronic equipment companies. Bayesian networks are used as a methodology for examining the supplier external risk profiles of the study sample.

The results of this study show that Bayesian networks can be effectively used to assist managers in making decisions regarding current and prospective suppliers with respect to their potential impact on supply chains as illustrated through their corresponding external risk profiles.

A limitation to the use of Bayesian networks for modeling external risk profiles is the proper identification of risk events and risk categories that can impact a supply chain.

The methodology used in this study can be adopted by managers to assist them in making decisions regarding current or prospective suppliers vis-à-vis their corresponding external risk profiles.

As part of a comprehensive supplier risk management program, companies along with their suppliers can develop specific strategies and tactics to minimize the effects of supply chain external risk events.

The purpose of this paper is to present an update of and the latest results from work on a project aimed at monitoring electronic products during the whole life cycle with embedded wireless components.

Business processes of the electronic manufacturing supply chain were analysed. A business case and the system opportunities for life cycle monitoring, based on embedded wireless components system were developed. Radio frequency identification (RFID) assembly technology was adapted for the integration of components into a multi‐layer printed circuit board (PCB).

By storing product‐related information into electronic products, tracing of components, monitoring of processes, operations and costs, environmentally optimised recycling can be enhanced.

The research undertaken so far relates to the embedding of RFID tags into PCBs. Wireless components with more processing power will be used in the next project phase.

The paper details how wireless components can be embedded into multi‐layer PCBs and how a business case for a life cycle monitoring system can be established.

The purpose of this paper is to compare various features of modular repair inventory flow in large maintenance organizations such as the Indian army with those of basic multi‐echelon repair inventory model METRIC.

Two models are selected and validated with user trials for a period of six months. A few performance measures for multi‐echelon repair inventory systems (MERIS) have also been identified using questionnaires. These two models are compared with the base model using developed performance measures and finally the most preferred model is identified which may replace the existing model. Finally, some recommendations are made for future researchers working in the area of multi‐echelon repair inventory systems.

The action research (AR)‐based approach has been used to solve a problem which is interactive and aims at developing a holistic understanding. A crisp codification scheme has also been suggested for a multi‐echelon repair inventory environment.

The paper demonstrates identification of inadequacies in the existing model of certain organizations and develops a number of alternate models with the prime objective of reducing the total number of echelons, using an AR‐based approach.

On the basis of empirical studies, the purpose of this paper is to identify and analyse product properties that affect performance of end‐of‐life systems for electrical and electronic equipment (EEE).

The research was carried out as case studies of end‐of‐life management of EEE. Case A focused on disassembly of computer screens and TV‐sets, whereas Case B addressed logistics systems for recycling of various types of EEE. Data collection methods include interviews, on‐site visits and observations, video recording, and studies of documents.

In total, nine product properties that affect performance of end‐of‐life systems for EEE are identified. The properties relate to three different product levels: the product assortment, the product structure, and the component levels. A model is presented which indicates that choices made and decisions taken in the product development process affect the end‐of‐life system performance. Application of modular product architectures and component standardisation are suggested as relevant design strategies during product development.

The implications for managers are that the findings presented in this paper provide strengthened arguments that modular product architectures and component standardisation are favourable approaches to apply in product development. Complementary to the benefits for manufacturing and logistics also end‐of‐life system performance will improve when these approaches are applied.

Previous research has indicated some product properties that are supposed to influence performance of end‐of‐life systems. These properties originate primarily from conceptual discussions rather than empirical studies. This paper adds to current understanding by presenting empirically‐based insights regarding which specific product properties affect performance.

This paper aims to present a review carried out under DEFRA‐funded project WRT208, describing: the composition of WEEE, current treatment technologies, emerging technologies and research.

This paper summarises the output from the first part of the project. It provides information on the composition of WEEE and an extensive survey of technologies relevant to materials recycling from WEEE. A series of further papers will be published from this research project.

WEEE has been identified as one of the fastest growing sources of waste in the EU, and is estimated to be increasing by 16‐28 per cent every five years. Within each sector a complex set of heterogeneous secondary wastes is created. Although treatment requirements are complicated, the sources from any one sector possess many common characteristics. However, there exist huge variations in the nature of electronic wastes between sectors, and treatment regimes appropriate for one cannot be readily transferred to another.

A very large number of treatment technologies are available, both established and emerging, that singly and in combination could address the specific needs of each sector. However, no single set of treatment methods can be applied universally.

This paper is the first part of work leading to the development of technical strategies and methodologies for reprocessing WEEE into primary and secondary products, and where possible the recovery of higher added‐value components and materials.

The purpose of this paper is to provide an overview on the e‐waste topic, highlight the economic arguments for dumping e‐waste in developing countries and examine the issues around the e‐waste problems in Nigeria.

The methodology adopted is based on a review of existing literature, personal observation and interviews.

Electronic waste, or e‐waste, has emerged as a major problem in quite a number of developing countries, as well as an opportunity for development and economic growth. As a result of its high toxic content, it creates problems of environmental pollution and is a hazard to human health when not handled properly. However, there is a huge demand for good quality, second‐hand equipment in developing countries and there seem to be strong economic arguments for exporting scrap electronic and electrical equipment to those countries. The e‐waste trade has grown in Nigeria, causing several socio‐economic problems.

The paper contributes to the growing body of knowledge on e‐waste in developing countries, especially Nigeria. It provides insight into the economic arguments that encourage the continuance of the e‐waste problem.

This is a large and complex subject and one which cannot be treated comprehensively and in depth in the course of a short lecture such as this. However, an attempt will be made to acquaint you with the main series of specifications and standards which are employed in the UK to shape and govern the design of aerospace vehicles and to say something about their purpose, broad classification and genesis.