Tarek Al-Hawari

Quality assurance and accreditation of engineering education in Jordan

This paper provides a study of the quality assurance and accreditation in the Jordanian higher education sector and focuses mainly on engineering education. It presents engineering education, accreditation and quality assurance in Jordan and considers the Jordan University of Science and Technology (JUST) for a case study. The study highlights the efforts undertaken by the faculty of engineering at JUST concerning quality assurance and accreditation. Three engineering departments were accorded substantial equivalency status by the Accreditation Board of Engineering and Technology in 2009. Various measures of quality improvement, including curricula development, laboratories improvement, computer facilities, e-learning, and other supporting services are also discussed. Further assessment of the current situation is made through two surveys, targeting engineering instructors and students. Finally, the paper draws conclusions and proposes recommendations to enhance the quality of engineering education at JUST and other Jordanian educational institutions.

IMPACT OF ASSIGNMENT, INVENTORY POLICIES AND DEMAND PATTERNS ON SUPPLY CHAIN PERFORMANCE

A simulation model is built to analyse the performance of a four-level/three-product supply chain composed of a retailer, distributor, manufacturer and supplier. The effects of assignment policies; preferred, cyclical and random, were analysed in combination with various factors such as inventory policies; continuous review (r, Q) and periodic review (T, S), and different demand patterns. On-hand inventory and percentage of satisfied customers at various levels of the SC are used as key performance indicators. In (T, 5) systems, it is found that imposing an upper limit on S in some SC levels due to the assumption that an order is shipped as a whole in one trip would greatly influence results. Consequently, an increase in T not associated with a sufficient increase in S would decrease inventory levels that would lead to shortages between orders. In (r, Q) systems, the results show clearly how the effect of increasing Q in one level is transformed to upstream and downstream levels. Upstream levels are all negatively affected, while downstream levels maintain the same levels of inventory without any noticeable trends. ANOVA results show that at low demand rates inventory policies are the most significant, then demand patterns while the assignment policies are mostly insignificant. At high demand rates the assignment policy factor becomes significant as well as the other two factors. Sensitivity analysis performed shows the robustness of the results under varying conditions.

A software application for E-Kanban-based WIP control in the aluminium industry

In this paper, a software application for an E-Kanban inventory control system is developed to track work-in-process (WIP) inventory and finished goods in an aluminium factory. The current paper work system is replaced with an E-Kanban system that will minimise the errors prone paper forms as well as data entry requirements. Results show that manufacturing lead time and WIP have been reduced by an average of 88% and 50%, respectively. Accountability measure has been built into the system to identify the errors. Reports about any order can be generated and managers can make decisions based on real-time information.

Simulation-Based Analysis and Productivity Improvement of a Fully Automatic Bottle-Filling Production System: A Practical Case Study

In this paper, a simulation study was carried out to improve the productivity of a fully automatic bottle-filling production system. An in-depth analysis of the system was performed in an attempt to increase its throughput and overall productivity. A simulation model was developed for the current system to ascertain its limitations and problems. The relevant performance measures are analyzed and a set of changes and improvements to the actual system were proposed. Furthermore, an optimization study on the relevant parameters was conducted in order to find the values that lead to increased productivity and throughput. In addition, downtime analysis was performed using statistical techniques to optimize uptime and reduce machine failures. Simple actions were suggested which can lead to considerable increase in efficiency, productivity and profitability of the system.

A software application for the selection of temperature measuring sensors using the analytic hierarchy process

This study presents a software application that applies the Analytic Hierarchy Process (AHP) to objectively select the best temperature sensors. Three industrial applications and seven sensor alternatives are considered. The developed application performs the selection process in a computerised, easy-to-use graphical user interface. The underlying decision method ranks temperature sensors with scores resulting from the synthesis of relative preferences of each alternative at different levels considering independent evaluation criteria. Pair-wise relative comparison matrices collected from experts are embedded and are retrieved according to user specifications. A case study is conducted which involves selecting the best sensor for an automotive catalytic converter. The thermocouple is found to be the most preferred sensor with the largest score of 0.37849, the second ranked sensor is the RTD with a score of 0.34589, and the least preferred sensor is the thermister with a score of 0.27560. Sensitivity analysis shows that the selection of the best sensor is dependent on the relative weights of the criteria as well as the chosen application. AHP is shown to provide a quantitative evaluation method which is simpler, easier and more organised than subjective opinions.

2D laser scanner selection using fuzzy logic

Research highlights? Fuzzy logic is used as a multi-criteria selection tool of 2D laser scanners. ? Selection criteria are identified and classified into static and dynamic based on their dependency on the application. ? The ability of fuzzy logic to deal with quantitative as well as qualitative factors is shown. Laser scanners are widely used today in many fields. This paper presents a multi-criteria decision-making selection process of these sensors for different applications using a fuzzy logic approach. Factors affecting the selection process are divided into dynamic and static ones based on their dependency on the application considered. Fuzzy sets and fuzzy rules are used to translate implicit and vague expert opinions provided in linguistic terminology into assessment ratings for different types of laser scanners based on the established factors. The laser scanner with the highest overall assessment rating is chosen as the best alternative for an application. Three laser scanner models from different manufacturers are compared using this method for a shape detection application and the best alternative is found. Results show that the fuzzy logic approach can easily deal with both qualitative and quantitative data and can identify quantitatively the best laser scanner for an application. Fuzzy logic enhances the understanding of the different factors that are the base for any comparison. Moreover, this approach reduces the effect of bias and subjective judgments made by the decision makers.

Development and evaluation of a Basestock-CONWIP pull production control strategy in balanced assembly systems

Abstract In this study, a new pull production control strategy called Basestock-Constant Work-in-Process (B-CONWIP) is proposed. It is used to control the flow of materials and information in balanced assembly production systems. This proposed control strategy uses one type of authorization cards called CONWIP card that limits the work-in-process (WIP) in the whole system. It has been applied in a single-product and a mixed-product assembly system balanced by two efficient Genetic algorithms introduced in literature. The performance of this control strategy is compared with another pull production control strategy called Basestock Kanban CONWIP (BK-CONWIP), which is a very promising production control strategy found in literature. The proposed strategy has two control parameters, CONWIP authorization cards and basestock levels while BK-CONWIP has three control parameters Kanban authorization cards, CONWIP authorization cards and basestock levels. The comparison is based on three performance measures average system WIP, percentage of satisfied customer demand (service level) and WIP variation between workstations. The performance of the proposed strategy B-CONWIP and BK-CONWIP is mainly similar in both types of assembly systems when mean demand rates are low with respect to mean service rates with the proposed strategy being easier to control and optimize. On the other hand, when mean demand rates are high with respect to mean service rates; B-CONWIP is preferable if service level is more important, while BK-CONWIP is preferable if WIP level is more important. Regarding WIP variation, it mainly depends on the efficiency of the balancing approach. The more efficient the balancing approach, the less WIP variation. Treating demand as lost instead of backordered results in decreased average system WIP and does not affect service levels in both PCSs. It is also shown that S-KDP is more flexible in dealing with situations of variable product mixes than d -KDP because control parameters can be used by any product which minimizes the effect of the unbalanced systems.

A Simulation Model for Performance Improvement of Triage-Based Emergency Care

Abstract— The paper presents a discrete event simulation model to evaluate the performance in an emergency department. Following evaluation of current state of emergency care, the study proposes establishing a general medicine clinic within or next to the emergency department such that patients with low emergency priorities can be directed to the clinic where they can see a non emergency physician. Results obtained from testing the proposed model illustrate performance advantage with respect to urgent classified cases ranging from 19.27% to 24.36% reduction in waiting time compared to it in the traditional emergency department system.

USING EXPANDED REAL OPTIONS ANALYSIS TO EVALUATE CAPACITY EXPANSION DECISIONS UNDER UNCERTAINTY IN THE CONSTRUCTION MATERIAL INDUSTRY

Capacity expansion generally requires large capital expenditure on illiquid assets. Therefore, decisions to enlarge capacity must support the organisation’s strategic objectives and provide valuable input for the budgeting process. This paper applies an expanded form of Real Options Analysis (ROA) to generate and evaluate capacity expansion strategies under uncertainty in the construction material industry. ROA is applied to different expansion strategies associated with different demand scenarios. Evaluating a wider variety of strategies can reduce risk and sponsor decisions that maximise the firm’s value. The case study shows that the execution of a lead expansion strategy with 10-year intervals under a 50 per cent demand satisfaction scenario produces superior results.

Selection of shielding gas by adaptive AHP decision model

Shielding gas selection in welding processes has major implications on the welding strategy. Selecting the appropriate gas is a multi-criteria decision making MCDM problem. Therefore, it is important to identify the criteria in the selection process. This study proposes a strategic justification tool for decision makers to select the most appropriate shielding gas based on the analytic hierarchy process AHP framework. The AHP method proposed ranks four of the most common shielding gases based on multi level criteria and the application at hand. The ranks are based on homogenous and independent evaluation criteria. The stability of the preference ranking was tested for robustness by sensitivity analysis. The process was effective in spotting the best shielding gas with the highest overall efficiency. The best shielding gas found was argon, followed by gas blend argon-helium, next came helium, and lastly carbon dioxide with overall weights of 0.315, 0.284, 0.22, 0.181, respectively.