https://repository.sustech.edu/handle/123456789/16557 2026-04-08T04:16:18Z 2026-04-08T04:16:18Z Abosinaina , Abdelrahim Mobarak Salih ,Sabir Mohamed https://repository.sustech.edu/handle/123456789/16564 2017-07-11T06:57:20Z 2012-01-01T00:00:00Z

Soba Upper- Draught Hoff-Mann Kiln Temperature Distribution Abosinaina , Abdelrahim Mobarak; Salih ,Sabir Mohamed This study aimed to convert the operation of Soba circular kiln, the top-fired one, with the suction of hot gases up-wards (upper- draught kiln), to the way of suction of heat down-wards (down-draught kiln) in order to draw and distribute the high concentrated quantity of heat at the kiln top-crown down- wards to the bottom of the kiln, and allover of it as much as possible. Suction-pipes of special specifications was used to link between the bottom of the kiln and the main exhaust suction-pipes system in order to draw the hot gases concentrated at the kiln top-crown, down-wards to the bottom of the kiln. Extensive field work and laboratory studies had been carried out during this study achieved a consistent results and finding lead to a good high quantity and quality of fired red bricks. article

2012-01-01T00:00:00Z Haroun , Ahmed E. Loghman , Adil H. A. Mahmoud , Salma Y. M . https://repository.sustech.edu/handle/123456789/16561 2017-07-11T06:59:00Z 2012-01-01T00:00:00Z

Scheduling Problem under Constrained Resources: A Historical Review of Solution Methods and Computer Application Haroun , Ahmed E.; Loghman , Adil H. A.; Mahmoud , Salma Y. M . In construction projects, project execution time is a major concern of the involved stakeholders (client, contractors and consultants). Optimization of project scheduling through time control is considered as a critical factor in project management. Many studies were carried out and many models and software packages were developed since the fifties and till now, but no clear cut methods, to optimize resources while satisfying different constraints were found. The importance of the subject stemmed from the fact that project time completion affects the overall project cost. Considering the most two widely applied scheduling methods: Critical Path method (CPM) and Program Evaluation and Review Technique (PERT), it is found that negligence of handling limitation of resources is evident in most cases. On the other hand, a resource leveling technique which is used to reduce the sharp variations in the resource demand histogram cannot handle the issue of1 minimizing project duration since it is used when there are enough resources. So the leveling process is accomplished by shifting only the non-critical activities within their floats. This paper show a number of heuristics and models to solve scheduling problem of projects subjected to limited resources. Different heuristic methods applied in past studies were examined in order to be tested and applied in a simple example, as a pilot study, so as to be used in real complex projects. article

2012-01-01T00:00:00Z Ahmed , Masoud Gamiel Elhassan , Basheir M. Bashar , K. E . https://repository.sustech.edu/handle/123456789/16562 2017-07-11T06:59:23Z 2012-01-01T00:00:00Z

Modeling Of Oil Spill Trajectory and Fate in Sudanese Red Sea Coastal Water Ahmed , Masoud Gamiel; Elhassan , Basheir M.; Bashar , K. E . Prediction and simulation of the trajectory and weathering of marine oil spills are essential to the development of pollution response and contingency plans, and the evaluation of environmental impact assessments. In this study, SL Ross Trajectory and fate modeling was applied to identify the shortest time for oil to reach Bashayer Red Sea shoreline in order to model the worst case scenarios. Four different scenarios were tested out, two for winter and two for summer. Results showed that in winter the spill movement is towards south and southwest while it moves to the northwest in summer. In both cases the spill will contact Bashayer Marine Terminal (BMT) shoreline within 4 hours in winter and 6 hours in summer rely on the combined effect of wind and tidal current. It was also shown that between 47.7 to 64% of the oil remain on the surface after 10 hours of spill. article

2012-01-01T00:00:00Z Ahmed, Aamir Hashim Obeid https://repository.sustech.edu/handle/123456789/16563 2017-07-11T06:59:38Z 2012-01-01T00:00:00Z

Performance Comparison of Sliding Mode Control and Conventional PI Controller for Speed Control of Separately Excited Direct Current Motors Ahmed, Aamir Hashim Obeid Direct Current (DC) motors have been used extensively in industry mainly because of the simple strategies required to achieve good performance in speed or position control applications. This paper addresses controlling of speed of a separately excited DC motor which remains among the vital issues. A separately excited DC motor is generally controlled by Proportional plus Integral (PI) controller. PI controller is simple but sensitive to parameter variations and external disturbance. Due to the robustness of Sliding Mode Control (SMC), especially against parameters variations and external disturbances, and also its ability in controlling linear and nonlinear systems; a separately excited DC motor sliding mode speed controller technique is proposed in this paper. Performance of these controllers has been verified through simulation results using MATLAB/SIMULINK software. The simulation results showed that SMC was a superior controller than PI controller for speed control of a separately excited DC motor. article

2012-01-01T00:00:00Z