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Article
Publication date: 5 March 2018

Benoit Delinchant, Guillaume Mandil and Frédéric Wurtz

Life cycle analysis (LCA) is more and more used in the context of electromagnetic product design. But it is often used to check a design solution regarding environmental…

Abstract

Purpose

Life cycle analysis (LCA) is more and more used in the context of electromagnetic product design. But it is often used to check a design solution regarding environmental impacts after technical and economical choices. This paper aims to investigate life cycle impact optimization (LCIO) and compare it with the classical life cycle cost optimization (LCCO).

Design/methodology/approach

First, a model of a dry-type transformer using different materials for windings and the magnetic core is presented. LCCO, which is a mixed continuous-discrete, multi-objective technico-economic optimization, is done using both deterministic and genetic algorithms. LCCO results and optimization performances are analyzed, and an LCA is presented for a set of optimal solutions. The final part is dedicated to LCIO, where the paper shows that these optimal solutions are close to those obtained with LCCO.

Findings

This paper investigated LCIO using an environmental impacts model that has been introduced in the optimization framework Component Architecture for the Design of Engineering Systems. The paper shows how a mixed continuous-discrete, multi-objective technico-economic optimization can be done using an efficient deterministic optimization algorithm such as Sequential Quadratic Programming. Thanks to the technico-economic-environmental model and the efficient optimization algorithm, both LCCO and LCIO were performed separately and together. It has been shown that optimal solutions are similar, leading to the conclusion that only one modeling is required (economic or environmental) but on the life cycle.

Originality/value

The classical sequential methodology of design is improved here by the use of a model of calculation of the environmental impacts allowing the optimization. This original optimization allowed the authors to show that an analysis of the life cycle from an economic point of view or from an environmental point of view led to quasi-equivalent technical solutions. The key is to take into account the life cycle of the product.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 37 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 8 May 2007

Andrea Pelzeter

The purpose of this paper is to demonstrate that the result of an optimisation via life cycle costs (LCC) depends on the assumptions made throughout the process of calculating LCC.

Abstract

Purpose

The purpose of this paper is to demonstrate that the result of an optimisation via life cycle costs (LCC) depends on the assumptions made throughout the process of calculating LCC.

Design/methodology/approach

A framework is used to structure the assumptions made in the process of calculating LCC. These include the following three pairs: technical versus economic life‐span, static versus dynamic calculation method or costs only versus income minus costs. In a broader sense, these LCC are referred to as the life cycle economy (LCE). Two case studies form the basis for the LCC calculations. Using different assumptions, the LCC of virtual design variations of these buildings are compared to each other.

Findings

The rankings drawn from the calculations differ according to the chosen calculation method, i.e. the chosen variation for the optimisation of a building is not consistent.

Research limitations/implications

This is essentially an exploratory study and the prognosis of future cash flow in relation to certain design variations requires further research.

Practical implications

The credibility of life cycle costing should improve with a greater transparency of assumptions in the context of the outlined framework.

Originality/value

All players in facilities management who support their decisions with LCC will benefit from this quantification of the impact of different calculation methods. The extension of LCC to LCE will help planners, investors and owners of real estate in evaluating building options with respect to quality, image, flexibility or comfort.

Details

Journal of Facilities Management, vol. 5 no. 2
Type: Research Article
ISSN: 1472-5967

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Article
Publication date: 7 March 2016

Sreedhar Karunakaran

The purpose of this paper is to eliminate the wastes and inefficient procedures in the maintenance organization of aircraft so as to reduce its downtime and increase…

Abstract

Purpose

The purpose of this paper is to eliminate the wastes and inefficient procedures in the maintenance organization of aircraft so as to reduce its downtime and increase mission availability.

Design/methodology/approach

Customized lean Six Sigma (LSS) was applied at the task level and servicing cycle level to reduce the task content, cycle length and resources in servicing. The loading of the servicing facility was simulated through a simulation program developed from a statistical analysis of historical data for validating/simulating/determining optimum loading of servicing facility with refined tasks, reduced cycle length and resources. In simulation, the optimum combination of manpower, resources and infrastructure at the facility level was determined through sensitive analysis and design of experiments (DoE).

Findings

Optimization at the task level and its re-organization at the servicing cycle level reduced the cycle length by 55-68 per cent and manpower resources by 26 per cent. This further reduced facility-level manpower by 25 to 40 per cent, capacity requirements by more than 33 per cent and annual aircraft downtime by 78 per cent. The approach reduced the average number of aircraft undergoing servicing at each airbase at any time from 2.35 to just 0.76 and increased the mission availability to 20 per cent.

Originality/value

The hallmark of the paper has been the design of LSS approach from structured historical data and its validation through innovative simulation. The multi-pronged bottom-up approach practically bundles all wastes resident in the maintenance organization. The paper provides cursory approach to lean practitioners in the elimination of wastes in the maintenance of capital assets like aircraft.

Details

International Journal of Lean Six Sigma, vol. 7 no. 1
Type: Research Article
ISSN: 2040-4166

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Article
Publication date: 7 March 2016

Laxman Yadu Waghmode and Rajkumar Bhimgonda Patil

Reliability analysis is required to identify the components or subsystems with low reliability for a given designed performance. Life cycle cost analysis helps understand…

Abstract

Purpose

Reliability analysis is required to identify the components or subsystems with low reliability for a given designed performance. Life cycle cost analysis helps understand the cost implications over the entire life span of a product. The purpose of this paper is to present a case study describing reliability analysis and life cycle cost optimization of a band saw cutting machine manufactured and used in India.

Design/methodology/approach

The data required for reliability analysis is collected from the manufacturer and users of band saw cutting machine. The parameters of failure distribution have been estimated by using ReliaSoft’s Weibull++6 software. The life cycle cost is divided into various cost elements such as acquisition cost, operation cost, failure cost, support cost and net salvage value.

Findings

The results of the analysis show that the components such as band wheel bearing, guide roller bearing, limit switch, carbide pad, hydraulic cylinder oil seal, control panel dial, control panel and solenoid valve are critical from reliability and life cycle cost analysis perspective.

Originality/value

With certain design changes it is found that the reliability of the system is increased by 15.85 percent while the life cycle cost is reduced by 22.09 percent. The study also shows that the reliability analysis is useful for deciding maintenance intervals.

Details

International Journal of Quality & Reliability Management, vol. 33 no. 3
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 1 December 1995

Biren Prasad

Continuous improvement is a cyclic process of product and processoptimization over a product life cycle. Optimization is beyond qualityand reliability management …

Abstract

Continuous improvement is a cyclic process of product and process optimization over a product life cycle. Optimization is beyond quality and reliability management – meaning, an organization is keeping in constant touch with new technological advances and frequently employs the applicable technologies to improve an existing product. Cycling means that an organization is continually exploring new frontiers in manufacturing technologies. The latest advances in related fields such as computers and systems are reviewed regularly for possible inclusion in the produced and process optimization cycle. Today, there is no single unique structure or process that defines “continuous improvement”, or, in a larger sense, what is described here as product and process optimization (PPO). Outlines a new structured approach to product and process optimization which includes, in addition to change management, three sets of metrics and measurements. PPO is a function of lifecycle management. There are three aspects of lifecycle management applicable to manu‐facturing and service industries: managing reprocessing, restructuring or re‐engineering change; managing continuity; and managing revision change.

Details

International Journal of Quality & Reliability Management, vol. 12 no. 9
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 13 August 2018

Hussan Saed Al-Chalabi

The purpose of this paper is to develop a practical economic replacement decision model to identify the economic lifetime of the ventilation system used by Trafikverket in…

Abstract

Purpose

The purpose of this paper is to develop a practical economic replacement decision model to identify the economic lifetime of the ventilation system used by Trafikverket in its Stockholm tunnels.

Design/methodology/approach

The proposed data-driven optimisation model considers operating and maintenance costs, purchase price and system resale value for a ventilation system consisting of 121 fans. The study identified data quality problems in Trafikverket’s MAXIMO database.

Findings

It is found that the absolute economic replacement time (ERT) of the ventilation system is 108 months but for a range of 100–120 months, the total cost remains almost constant. Sensitivity and regression analysis showed that the operating cost has the largest impact on the ERT.

Originality/value

The results are promising; the company has the possibility of significantly reducing the LCC of the ventilation system by optimising its lifetime. In addition, the proposed model can be used for other systems with repairable components, making it applicable, useful and implementable within Trafikverket more generally.

Details

Journal of Quality in Maintenance Engineering, vol. 24 no. 3
Type: Research Article
ISSN: 1355-2511

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Article
Publication date: 5 February 2018

Chanchal Ghosh, J. Maiti, Mahmood Shafiee and K.G. Kumaraswamy

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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

Details

International Journal of Quality & Reliability Management, vol. 35 no. 2
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 21 March 2008

Eric Korpi and Timo Ala‐Risku

Despite existing life cycle costing (LCC) method descriptions and practicable suggestions for conducting LCC analyses, no systematic analyses on actual implementations of…

Abstract

Purpose

Despite existing life cycle costing (LCC) method descriptions and practicable suggestions for conducting LCC analyses, no systematic analyses on actual implementations of LCC methods exist. This paper aims to review reports on LCC applications to provide an overview of LCC uses and implementation feasibility.

Design/methodology/approach

A review of LCC cases reported in academic and practitioner literature. Case reports were compared against one another and against the defining articles in the field.

Findings

Most of the reported LCC applications were far from ideal. Compared to the methods suggested in the literature many of the case study applications: covered fewer parts of the whole life cycle, estimated the costs on a lower level of detail, used cost estimation methods based on expert opinion rather than statistical methods, and were content with deterministic estimates of life cycle costs instead of using sensitivity analyses.

Research limitations/implications

This review is limited to reported LCC applications only. Further research is encouraged in the form of a field‐based multiple‐case study to reveal context‐specific dimensions of LCC analysis and implementation challenges in more detail.

Practical implications

This review highlights the difficulty of conducting a reliable LCC analysis, and points out typical problems that should be carefully considered before drawing conclusions from the LCC analysis.

Originality/value

First systematic analysis of LCC applications that gives directions for further research on the LCC concept.

Details

Managerial Auditing Journal, vol. 23 no. 3
Type: Research Article
ISSN: 0268-6902

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Article
Publication date: 18 October 2011

Ying Nan Yang and Mohan M. Kumaraswamy

This paper aims to present approaches towards improving some specific infrastructure maintenance principles, strategies, models and practices, based on a recent study of…

Abstract

Purpose

This paper aims to present approaches towards improving some specific infrastructure maintenance principles, strategies, models and practices, based on a recent study of bridge management systems in Hong Kong. A specific goal is to develop better informed and more systematic approaches to condition assessment, deterioration forecasting, and maintenance decision making over the lifecycle of the built asset.

Design/methodology/approach

Improved performance prediction and decision‐making approaches are developed and presented based on a research exercise to formulate a maintenance management framework for concrete bridge elements in Hong Kong. This includes for example, the presentation of decision‐making approaches for optimizing inspection intervals on bridge expansion joints.

Findings

The findings show that judicious integration is needed in incorporating valuable elements of, and lessons learned from, previous practice with proposed new strategies/ principles, models and practices for specific scenarios.

Practical implications

Based on the findings, practitioners' understandings can be deepened as regards the barriers to improving condition assessment, deterioration forecasting, and maintenance decision making over the lifecycle of the built asset. Furthermore, the results also provide useful information for developing strategies and practices to improve currently used infrastructure management systems.

Originality/value

Major obstacles are overcome in developing better informed and more systematic approaches as above, and in extending current knowledge on condition assessment, performance prediction and decision‐making models by utilizing more pertinent data and addressing some barriers in practical implementation.

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Article
Publication date: 13 April 2018

Filipa Salvado, Nuno Marques de Almeida and Alvaro Vale e Azevedo

Stakeholders of the Architecture, Engineering and Construction (AEC) sector require information on the buildings economic performance throughout its life cycle. This…

Abstract

Purpose

Stakeholders of the Architecture, Engineering and Construction (AEC) sector require information on the buildings economic performance throughout its life cycle. This information is neither readily available nor always accurate because building management (BM) professionals still face difficulties to fully incorporate the life cycle cost (LCC) concept into their daily practice. The purpose of this paper is to identify and contribute to solving these difficulties.

Design/methodology/approach

This paper provides a background knowledge review and set the ground for a structured research roadmap and a management framework that highlight the links and limitations to be addressed within and between LCC and BM. A six-stage method was used for developing conceptual frameworks targeting six goals: establishing a point of departure; mapping sources of information; literature research; notion deconstruction and conceptual categorization; overview of the applicable background knowledge; and structuring of a framework for LCC-informed decisions in BM.

Findings

Management solutions for the built context are necessarily connected with LCC and BM current concepts such as asset management, project, program and portfolio management, facility management and data management. These management approaches highlight the importance of incorporating life cycle concepts and promote LCC effective application within the AEC sector.

Originality/value

This paper identifies and discusses current limitations on the information availability for the economic performance of buildings throughout its life cycle. This work also identifies LCC-related topics that need to be further explored or addressed by both the scientific community and practitioners to overcome these limitations and facilitate the integration of the LCC concept into BM activities.

Details

Built Environment Project and Asset Management, vol. 8 no. 2
Type: Research Article
ISSN: 2044-124X

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