Adnan Mukattash

Crashing PERT networks using mathematical programming

Abstract The paper introduces and develops a method for investigating the application of mathematical programming to the concept of crashing in Program Evaluation and Review Technique (PERT). The main objective is the minimization of the pessimistic time estimate in PERT networks by investing additional amounts of money in the activities on the critical path. The constructed mathematical model, which is built in terms of additional amounts of money that must be invested, shows that minimizing the pessimistic time decreases project duration and, at the same time, reduces its variance. The result of applying the model showed that the probability of realizing the terminal node is increased.

Design and analysis of production control scheme for Kanban-based JIT environment

Abstract This paper aims at designing production control scheme for Kanban-based just-in-time (JIT) environment. Synchronization mechanism for a single-stage single-product Kanban-controlled production line is developed, in such a way that yields a feasible operating cost as well as a feasible average of work-in-progress (WIP). The Kanban production line is formulated as ( M / M / s : GD / ∞ / ∞ ) queuing model. A new approach for analyzing the queue model is discussed. An operating cost model is then developed to determine the unknown parameters of the system. Numerical examples are used to demonstrate the computations of different system parameters. Avenue for future research is also indicated.

Heuristic approaches for part assignment in cell formation

Since the cell formation problem is considered to be a complex and multi-criteria problem, then no single algorithm can provide all the promised benefits. To gain more benefits of the cell formation, three heuristic procedures are developed in this paper to give the designer more flexibility to generate cells. Given a cell formation solution, the heuristics are designed to assign parts to the cells in the presence of alternative process plans, multiple alternative (parallel) machines, or when processing times are taken into consideration.

A modified revised P-median approach to cell formation

The point of weakness of the revised P-median approach for solving the cell configuration, problem using cluster analysis, is that the optimal number of cells might not be achieved by this approach. The optimal number of cells is the solution, which gives the minimum sum of the number of voids inside the diagonal blocks and number of the ones outside the blocks. This paper presents a modified approach to overcome the point of weakness of the revised P-median approach, by specifying the number of cells in advance, and by controlling the cell size, with lower and/or upper bounds of machines inside the cell.

Decomposition analysis of electricity use in the Jordanian industrial sector

This paper is focused on the electricity demand of the industrial sector in Jordan, since it is responsible for about 24.15% of the total electricity consumption in the country. Analyses of the changes in energy demand for the years 2008–2013 and the factors affecting this demand are investigated in this study. The modified Laspeyers factor decomposition approach is used to give a more precise estimate of how changes in industrial production, structural, and efficiency effects contributed to the changes in electricity demand. The Jordanian industrial sector was disaggregated into twenty two sub-sectors according to International Standard Industrial Classification of All Economic Activities (ISIC). A major finding of this paper is that although increased industrial production caused energy demand to increase between 1998 and 2005, significant improvements in energy efficiency and structural shift have contributed to reducing the rate of this increase.

Critical analysis of modified grouping efficacy measure; new weighted modified grouping efficiency measure

Abstract Different grouping efficiency measures have been used to evaluate block-diagonal forms in group technology. One of the well-known measures is grouping efficacy. Many grouping efficiency measures were developed in the literature are based on or derived from grouping efficacy. One of these measures is called modified grouping efficacy (MGE). The limitation of MGE measure is that the case of zero efficiency can’t be determined. Moreover, the efficiency of the system is close to zero or very low compared with other measures in the case, where the number of voids is greater than number of exceptions inside the cell. To overcome these limitations, a new measure called weighted modified grouping efficacy is developed in this paper. This measure is tested against some problems from the literature and the results demonstrate the ability of this measure to be used in the evaluation of all types of Structure data.

Potential CO2 reduction through restructuring the Jordanian utility sector

This study attempts to predict the potential CO2 reduction due to pre-proposed future restructuring scenarios toward clean generation technologies for the Jordanian utility sector. The calculation is based on CO2 emission for unit electricity generated and the changing type of fuel percentages for electricity generation in Jordan. It was found that such restructuring will significantly contribute to undermine the global greenhouse gases emissions. The potential CO2 reductions by gradually introducing energy sources substitutions for electricity generation in Jordan are in a range of 1413−12,170 million kg for different suggested scenarios by year 2028.