Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Cycle time


A Novel Recursive Heuristic Algorithm for Straight and U-Shaped Assembly Line Balancing with Fuzzy Processing Time

Samah. A. Aufy; AllaEldin. H. Kassam

Engineering and Technology Journal, 2021, Volume 39, Issue 3, Pages 477-487
DOI: 10.30684/etj.2021.168127

The paper aims to address the straight and U–type assembly line balancing problems by developing a novel recursive heuristic algorithm based on the idea of the depth of search. The dynamic fuzzy processing time (DFPT) model is employed to represent uncertainty and ambiguity related to the processing time in the actual production systems. The novel algorithm, the minimum cycle time objective is considered for a set of imposed considerers. They are arranged in an appropriate strategy in which three-stages are proposed and presented as a solution approach. Finally, the validity of the developed solution approach is evaluated through a tested numerical example conducted over a test problem taken from literature to assess its performance. This study proofs their ability and efficiency in assisting decision-making by determining the contribution proportion for significant assignment variables represented by skill level, work stability, type layout, and priority rule

Examining Rebalancing Considers of the Mixed-Model Assembly Line Type-II for the Straight and U-shaped Layout Using the Taguchi Method

Samah. A. Aufy; AllaEldin. H. Kassam; Ghanim A. Ismeal

Engineering and Technology Journal, 2021, Volume 39, Issue 2, Pages 280-294
DOI: 10.30684/etj.2021.168111

Facing the increasingly competitive market environment, assembly lines are gained attention because of the assembly process expenditure consumes more than 20 % of the manufacturing cost, and also improve its products to meet demand. In this paper, an attempt has been made to develop worker-task assigned to workstation heuristic (W-TAWH) approach for solving mixed-model assembly line balancing problem (M-MALBP), in which the assembly tasks have to be assigned to workstations, and each workstation needs to select only one of the available operators to perform the assigned tasks corresponding to the straight and U-shaped assembly lines with the objective minimum cycle time. The performance of the developed approach was evaluated and validated through applying the practical case in the Dayla State Company for Electrical Industries (DSCEI) particularly in the electric transformer factory (ETF). Taguchi method was used to evaluate the contribution of each one of the considerations in the assembly line are solution approach, layout, sequence vector (SV), and workstation numbers. All results proved the stated considerations have impact significant in any trying to re-balance the assembly line.

Evaluation The Performance of Al-Thawra At-Grade Intersection Using The HCS2000 Computer Package

Ali Majeed K.Al-Ubadiy; Zeena Tariq Al-Azzawi; Nawal Dawood S

Engineering and Technology Journal, 2010, Volume 28, Issue 15, Pages 5088-5101

Al-Thawra signalized intersection is one of the most important intersections in AL-Hilla city because it relates the Governorates: Baghdad, Najaf, Kerbala and Babel, and serves of about 21000000 passages of vehicles yearly. The excessive traffic volumes, during the peak periods (at morning and evening), of vehicles that entering the
intersection increase traffic density, reduce travel speed, increase travel time, and increase the delay values. The delay values are reflected by McTrans Center, University of Florida {Highway Capacity Manual (HCM2000)} to an indicator named LEVEL OF SERVICE (LOS). The operational analysis of the existing conditions of this intersection
by the Highway Capacity Software (HCS2000) indicates that the LOS of it equal to (F) with an intersection delay value of 263.7 sec./vehicle and a degree of saturation exceeds 1.5. Therefore, and because of the reasons above, it is important to improve the performance of Al-Thawra Intersection by separate the conflicting traffic movements
with an overpass bridge. The traffic survey shows that the high traffic volume of through movement of the North-South direction (Baghdad-60St.) has the major effect on the intersection. Therefore, the North-South is the suitable direction to construct the suggested bridge overpass to separate the through traffic of this direction (from Baghdad
to Najaf {60 St.} and vice versa) from the other movements of the intersection. The results indicate that the intersection LOS equal (C) with a cycle time of (58) sec. and an intersection delay of (22.8) (sec./veh.) at the object year 2027.