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The modern helicopters are designed with maximum serviceability and long life expectancy to ensure minimum life cycle cost. The purpose of this paper is to present a framework to incorporate the customer requirements on reliability and maintainability (R&M) parameters into the design and development phase of a contemporary helicopter, and to discuss the way to capture operational data to establish and improve the R&M parameters to reduce life cycle cost.

From the analysis, it is established that the reliability and maintainability cost is the major contributor to the life cost. The significant reliability and maintainability parameters which influence R&M cost are identified from analysis. The operational and design data of a contemporary helicopter are collected, compiled and analyzed to establish and improve the reliability and maintainability parameters.

The process depicted in the paper is followed for a contemporary helicopter and substantial amount of life cycle cost reduction is observed with improvement of R&M parameters.

The benefits of this methodology not only reduce life cycle cost but also improve the availability/serviceability through less failure and less time for scheduled maintenance. The methodologies also provide the reliability trends indicating potential area for design improvement.

The proposed approach assists asset managers to reduce the life cycle costs through improvement of R&M parameters.

Companies face the critical reliability problem of products due to the development of outsourcing. This study intends to provide some feasible solutions for a company to improve the reliability level of products.

The paper considers the reward and reliability decisions regarding a product made with two complementary components from two different suppliers: high-capable and low-capable. Two kinds of reliability improvement incentives (normal incentive and cost-sharing incentive) through which a manufacturer provides a reward and shares the reliability improvement cost with a supplier are discussed. As the Stackelberg leader, the manufacturer determines the strategy, while the suppliers are responsible for determining its reliability. Using a game-theoretic framework, four different contract scenarios are addressed. We develop analytical methods to better understand how the manufacturer decides the incentive mechanism to be used for the suppliers.

The results show that cost-sharing contracts do not always lead to a higher reliability level and more enormous profits. Setting a target reliability level is better for the manufacturer. The cost-sharing contract is beneficial for a high-capable supplier even though it does not directly participate in that kind of mechanism. A low-capable supplier gains more profit when the manufacturer provides incentive mechanisms that do not specify a target reliability level.

This paper investigates the reliability improvement mechanism used for complementary products and focuses on identifying the optimal decisions when demand is influenced by the gap between the product's failure rate and the standard failure rate.

Provides a comprehensive and evaluative account of product reliability across a number of different dimensions. Through utilizing secondary sources of data and supported by some preliminary qualitative research findings, attempts to decompose those elements which have a direct relevance to product reliability improvement. To this end, provides a conceptual framework which can be integrated within the whole business interaction entities to enable reliability to be adequately considered throughout the life cycle phases.

System reliability optimisation in today’s world is critical to ensuring customer satisfaction, businesses competitiveness, secure and uninterrupted delivery of services and safety of operations. Among many systems configurations, complex systems are the most difficult to model for reliability optimisation. The purpose of this paper is to assess the performance of a novel optimisation methodology of the authors, developed to address the difficulties in the context of a gas carrying system (GCS) exhibiting dual failure modes and high initial reliability.

The minimum cut sets involving components of the system were obtained using the fault tree approach, and their reliability constituted into criteria which were maximised and the associated cost of improving their reliabilities minimised. Pareto optimal generic components and system reliabilities were subsequently obtained.

The results indicate that the optimisation methodology could improve the system’s reliability even from an initially high one, granted that the feasibility factor for improving a component’s reliability was very high. The results obtained, in spite of the size (41 objective functions and 18 decision variables), the complexity (dual failure modes) and the high initial reliability values provide confidence in the optimisation model and methodology and demonstrate their applicability to systems exhibiting multiple failure modes.

The GCS was assumed either failed or operational, its parameters precisely determined, and non-repairable. The components failure rates were exponentially distributed and failure modes independent. A single weight vector representing expression of preference in which components reliabilities were weighted higher than cost was used due to the stability of the optimisation model to weight variations.

The high initial reliability values imply that reliability improvement interventions may not be a critical requirement for the GCS. The high levels could be sustained through planned and systematic inspection and maintenance activities. Even so, purely from an analytical stand point, the results nevertheless show that there was some room for reliability improvement however marginal that is. The improvement may be secured by: use of components with comparable levels of reliability to those achieved; use of redundancy techniques to achieve the desired levels of improvement in reliability; or redesigning of the components.

The novelty of this work is in the use of a reliability optimisation model and methodology that focuses on a system’s minimum cut sets as criteria to be optimised in order to optimise the system’s reliability, and the specific application to a complex system exhibiting dual failure modes and high component reliabilities.

The purpose of this paper is to develop an approach for quantifying the operational value of IT‐enabled reliability improvement in a supplier network.

Specifically, the paper investigates an e‐procurement scenario involving emergency material purchases where web services provide for real‐time response, a dynamic supplier set, and the ability to perform cross‐enterprise purchase processes in an inter‐operable fashion. The paper proposes engineering reliability models for three network configurations as a basis for quantifying the value of web services, and develops a numerical illustration to both test its usefulness and to derive preliminary insights into supplier network design in this environment.

This research finds that a stand‐by model is descriptive of reliability in networks where suppliers are identified and managed using web services, and that this approach quantifies operational improvement in this type of e‐procurement system. The research also finds that the benefit derived from using web services for emergency purchases depends on the characteristics of the supply network itself, specifically the failure frequency of the existing suppliers and the time to restore operation after a failure occurs.

These findings are important to information system managers when assessing the financial and technical benefits of real‐time and dynamic information technologies, as well as supply chain managers seeking to implement a dynamically configured supply network. Future research directions include extensions of the reliability models, data acquisition for specifying their parameter values, and investigation into the usefulness of this approach in hardware decisions of web services applications in business.

Define, measure, analyze, improve and control (DMAIC) and define, measure, analyze, design and verify (DMADV) are two Six Sigma methodologies that improve quality in a process or product. In general, if the product design improvement in reliability cannot satisfy the failure‐free performance of Six Sigma, the DMADV process is used to create or redesign new product designs. However, the original function may be affected, and the product development cycle time may be enhanced due to a redesigned process. This paper aims to propose a new procedure to combine the reliability parameter and critical to quality (CTQ) to improve a product's reliability and to reduce the number of engineering changes without redesigning.

The study influences the failure parameter to find out the mean time to failure (MTTF) tree and utilizes the DMAIC process for improvement. It is important to maintain the function while improving time. This study looks at a cold cathode fluorescent lamp (CCFL) case.

The CCFL case uses the DMAIC process finds that important root cause improvement can increase MTTF twofold.

The paper provides useful information on product reliability improvement using the DMAIC process.

In the last 20 years, e-waste has become a serious issue resulting from an overwhelming amount of electronics consumption. However, there has been limited research on how to decrease such waste in a structured manner. Toward study was to use a simulation methodology to investigate the dynamics of upfront investment in reliability enhancement promoted by performance-based contracting (PBC), based on the number of spare parts and duration of the contract.

The present research first details the relevant mathematical equations and uses game theory to demonstrate the utility for supplier and buyer relationships. Next, the effects of reliability enhancement, spare partsPBC are analyzed using a BlockSim simulation model.

The results indicate strong relationships among system design cost, reliability, availability and service cost. The authors found that investment in reliability increases system availability while reducing total service costs. Furthermore, increasing the spare parts inventory was determined to have less influence on the readiness of highly reliable systems. The findings support the notion that PBC reduces e-waste by increasing system availability, incentivizing upfront investment in reliability growth.

Recognition of these findings in the context of buyer–supplier relationships will help managers better understand the value of upfront reliability investment, reducing maintenance, repair and overhaul requirements, avoiding the need to plan for extra spare parts and minimizing volume and the resulting e-waste.

This study also clarifies the uncertainty associated with upfront investment and provides potential incentives for suppliers.

The main contribution of this study is its use of PBC for e-waste reduction, highlighting the effects of upfront investment in reliability enhancement. The authors applied a game theory model to illustrate the relationship between incentives and upfront investment and demonstrate how increased levels of spare parts can be counterproductive to achieving readiness, reducing inventory and consequent e-waste.

In the public sector, Training and Experience (T & E) exams assess prior experience and are one of the most often used methods for selecting job applicants. This study uses a KSA approach, where raters judge the quality of job relevant prior experience, not its duration or quantity. It was hypothesized that an additional rater and a consensus meeting between raters would increase reliability and validity.

T & E and supervisory ratings were obtained over a 12-year period for 166 candidates seeking promotion to a budget analyst position. Validity was measured by the correlation between T & E scores and supervisory ratings. Consensus was required only for T & E scores differing by a specific amount (hybrid consensus).

Intraclass reliability was 0.73, 0.84, and 0.95 in the one-rater, two-rater, and hybrid consensus conditions with each coefficient greater than the next (p < 0.05) showing the benefit of multiple raters and consensus for reliability. Validity was significant at 0.21, 0.26, and 0.251 for each rating condition, respectively (two-tail test; p < 0.01). Validity was greater in the two-rater condition than in the one-rater condition (one-tail test; p < 0.05). Consensus did not improve validity beyond that of two raters. For consensus T & Es (n=76), two raters improved validity (one-tail test; p < 0.05), moving from 0.112 to 0.231 but not reliability; consensus improved reliability (two-tail test; p < 0.05) but not validity.

There has been a vacuum in T & E research for close to 20 years. Validity data are difficult to obtain but critical for meta-analysis. T & Es showed validity. Use of two raters improved validity but consensus did not increase the gain.

Reliability is a major quality characteristic which has grown in importance as products/systems have become ever more sophisticated. Neglecting it could spell great losses in terms of patronage, revenue, and even lives. The purpose of this paper is to present a multi‐criteria optimisation model and methodology for the Pareto optimal assignment of reliability to the components of a series‐parallel system in order to maximise its reliability.

The subsystems' reliabilities are maximised independently but simultaneously in order to maximise the overall system reliability, while a penalty function modelling cost of reliability improvement is minimised. The resultant continuous and nonlinear optimisation problem is scalarised by a convex combination of the criteria and the MATLAB Optimisation Toolbox is used to generate the solutions.

The results for an illustrative example problem extracted from the literature show that: higher reliabilities could be assigned to the components, in order to achieve or exceed target system reliability; cost increased sharply with slight improvements in the component reliabilities, and the model was stable under the weighting scheme used.

The novelty of this work is in: the multi‐criteria optimisation view taken of the design problem; the focus on the subsystems' reliabilities and cost as the criteria to be optimised; the use of the two aforementioned qualities for the purpose of Pareto assignment of component reliabilities in a system's design; and the use of the model and methodology in the context of series‐parallel systems.

This paper is focused at studying the current state of research involving the four dimensions of defect management strategy, i.e. software defect analysis, software quality, software reliability and software development cost/effort.

The methodology developed by Kitchenham (2007) is followed in planning, conducting and reporting of the systematic review. Out of 625 research papers, nearly 100 primary studies related to our research domain are considered. The study attempted to find the various techniques, metrics, data sets and performance validation measures used by researchers.

The study revealed the need for integrating the four dimensions of defect management and studying its effect on software performance. This integrated approach can lead to optimal use of resources in software development process.

There are many dimensions in defect management studies. The authors have considered only vital few based on the practical experiences of software engineers. Most of the research work cited in this review used public data repositories to validate their methodology and there is a need to apply these research methods on real datasets from industry to realize the actual potential of these techniques.

The authors believe that this paper provides a comprehensive insight into the various aspects of state-of-the-art research in software defect management. The authors feel that this is the only research article that delves into the four facets namely software defect analysis, software quality, software reliability and software development cost/effort.