Imad Alsyouf

Selecting the most efficient maintenance approach using fuzzy multiple criteria decision making

We assess the most popular maintenance approaches, i.e. strategies, policies, or philosophies, using a fuzzy multiple criteria decision making (MCDM) evaluation methodology. We illustrate with two examples how the suggested evaluation methodology identifies the most informative approach. Using the fuzzy MCDM, it would be possible to select in advance, the most informative (efficient) maintenance approach. Consequently, this leads to less planned replacements, and failures would be reduced to approximately zero and higher utilization of component life can be achieved. Thus, the maintenance department could contribute more to the business objectives throughout participating effectively in adding value to the production activities.

Enhancing a company's profitability and competitiveness using integrated vibration-based maintenance: A case study

In this paper a model is developed for identifying, monitoring and improving the economic impact of vibration-based maintenance (VBM). This model provides an additional possibility of identifying w ...

Improving Effectiveness of Manufacturing Systems using Total Quality Maintenance

In manufacturing systems intelligent techniques are being used to integrate and interpret data from multiple sensors to predict tool wear and tool life. Less attention is devoted to developments of integrated condition monitoring systems, which enable the user to evaluate a multi‐variant system based on the data collected from, e.g. maintenance, quality, production, etc. In this paper we discussed different approaches of how to keep availability, quality and productivity at high levels. Also, we proposed a new approach for an expert system concept, which is characterised by using a total quality maintenance (TQMain) concept; having a common database, and a continuously improved knowledge base with an intelligent inference engine. It can enhance data reliability, decision making certainty, remove the redundancy in monitoring systems, and allow the user to detect and eliminate reasons behind variations through effective diagnosis and prognosis. This will enhance the performance‐efficiency, availability and quality rate, i.e. overall equipment effectiveness of the manufacturing systems.

Design and implementation of a Lean Six Sigma framework for process improvement: A case study

The purpose of this paper is to develop a Lean Six Sigma framework according to the Six Sigma systemic process improvement methodology; Define, Measure, Analyze, Improve and Control (DMAIC). It was implemented and verified at one engineering company in UAE. The results show that the process “Make-to-Order (MTO) projects” has a long lead-time. The main causes of the long lead-time are the subcontractors, the customers, and the company-implemented procedures. Using the framework, it was possible to identify the most significant reason for the long lead-time, analyze the root-cause(s), suggest three relevant solutions and select the most preferred one. Using the framework methodology the user will have a systematic approach for continues improvement. The originality of this methodology was evident in integrating and using tools related to lean-production, six-sigma, balanced scorecard, simulation and cost benefit analysis. The framework allows the user identify the process problem(s) and solve them effectively.

Improving reliability of repairable systems using preventive maintenance and time-between-failures monitoring

The purpose of this article is to investigate how to assess the rate of occurrence of failure (ROCOF) of a multi-component repairable system and improve its reliability. A procedure was developed and tested on closed-circuit television dome cameras operated in an airport in the United Arab Emirates. Optimum replacement times for critical components were calculated, and then a practical preventive maintenance schema was suggested to reduce the overall cost. Finally, a control chart was developed to monitor the time between failures (TBFs) on the basis of the calculated ROCOF. The results of the case study show that optimising the maintenance renewal intervals generated a saving of approximately 77% in maintenance costs, reduced the ROCOF by approximately 94%, and increased the level of planned maintenance by approximately 97%. Furthermore, monitoring the TBFs of repairable systems could detect changes that might lead to failures over time, thus improving the reliability and ensuring the effectiveness of preventive maintenance. [Received 12 April 2015; Revised 27 December 2015; Revised 3 March 2016; Accepted 18 March 2016]

Mishandled baggage problem: Causes and improvement suggestions

The purpose of this paper is to identify the causes of mishandled baggage and suggest effective solutions. This study is conducted at one of the international airports in UAE, at the baggage handling department. We used a procedure that consists of five phases based on six sigma methodology: Define, Measure, Analyze, Improve and Control. Each phase has several steps using relevant engineering tools. Both qualitative and quantitative data were collected and analyzed. Consequently, four main problems were identified: lack of adequate training, long working shift, conveyor system breakdown, and falling bag. It was possible to identify the critical causes for these problems, suggest relevant solutions and select the most preferred ones. The suggested procedure enables the decision maker to measure the performance with respect to the set target. Thus, it will be possible to handle the challenges and reduce the mishandled baggage problem and improve the performance and competitiveness.

A multi-criteria decision-making framework for assessing the quality and cost of facility layout alternatives: a case study

The paper presents a multi-phase framework for assessing the quality and cost of facility layout alternatives. The framework utilizes life-cycle cost analysis (LCCA) and multi-criteria decision-making (MCDM) to account for economical and qualitative aspects. Life-cycle considerations include costs of development, investment, construction or production, usage, and scrapping. A test of the proposed framework was performed at the Swedish Mail Terminal in the town of Alvesta, a part of Posten Sweden AB. The terminal has several space, machine, and operational constraints. Three layout alternatives were developed and evaluated using the suggested framework. Although the selected layout alternative has the highest implementation cost, it yields a 9 per cent better total life-cycle cost than the closest alternative based on a ten year life-cycle length. The originality of this approach is evident in addressing both quantitative and qualitative facility planning issues such as economical and non-economical aspects, using both LCCA and MCDM methodologies. The approach proposed in this paper is not only valuable in this case study, but it can also be generally applied in other similar decision situations.

Using Lean Six Sigma to improve mobile order fulfilment process in a telecom service sector

Abstract This study proposes and follows a specific and systematic framework for implementing Lean Six Sigma (LSS) methodology in a telecom company in order to improve customer satisfaction by minimizing the company’s response time to customer requirements. The goal of this study was achieved by utilizing several LSS tools under five phases of the DMAIC methodology. Unlike previous studies in the telecom sector that used only qualitative method, in this study, both qualitative and quantitative methods were utilized to draw meaningful conclusions. As a result of the implementation of the LSS methodology, the average order fulfilment lead time for sales orders (SO) and value-added service (VAS) orders was reduced from 10.3 to 5.9 days and from 1.5 to 0.5 days, respectively. The reduction in lead time resulted in an increase in the sigma level for SO and VAS orders from 0.44 to 1.26 and from 0.73 to 2.66, respectively. These improvements were expected to lead to a financial benefit in savings of over

Green Traveling Purchaser Problem model: A bi-objective optimization approach

600,000 per year in operational costs, enhancements to customer experience and an increase in revenue generating opportunities. Moreover, this article enriches the existing literature on the application of LSS concept in the service industry, and helps the company to speed up the response to customer requirements.

A multi-objective optimization of maintenance policies using weighted comprehensive criterion method (WCCM)

The green traveling purchaser problem (GTPP) is a generalization of the Traveling Purchaser Problem which consists of selecting suppliers, allocating orders and choosing the best routes, while minimizing the purchasing and traveling costs and CO2 emissions. The two objective functions pertaining to minimization of CO2 emissions and purchasing costs are in some cases conflicting and are thus considered separately. This paper presents an exact method to solve the proposed bi-objective optimization model where the bi-objective mathematical model is transformed into a single objective function model using the weighted comprehensive criterion method. The model is solved using branch and cut algorithm in MATLAB software. Computational experiments were carried out using two random instances, and the results show that the algorithm gives the bi-objective Pareto optimal solutions with significant difference in computation times when the speed is constant or varies between the routes. Using different weighting factors, this model can be considered as a decision making tool that allows decision makers to use the solution that fits the most with their organizations strategy.