Volume 14 No. 2https://repository.sustech.edu/handle/123456789/165652024-03-29T04:39:00Z2024-03-29T04:39:00ZModeling of mortality rate of heterotrophic bacteria due to chromium in waste stabilization pondMayo , Masoud Gamiel Ahmed Adli,A. W.https://repository.sustech.edu/handle/123456789/165672017-07-11T07:03:42Z2013-01-01T00:00:00ZModeling of mortality rate of heterotrophic bacteria due to chromium in waste stabilization pond
Mayo , Masoud Gamiel Ahmed Adli,A. W.
Bacteria play an important role in oxidation and stabilization of organic and inorganic matter in wastewater treatment plant. This paper presents the development of mathematical model to study the effect of chromium on heterotrophic bacteria in waste stabilization pond. The governing equation of the model is based on the Haldane equation. The model developed reflects the mortality rate of heterotrophic bacteria at variable pH and concentration of chromium. To verify the computed results a series of laboratory experiments has been carried out, the predicted mortality rate was obtained from these models and compared with experimental data. The correlation coefficient R2 was 0.87.
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2013-01-01T00:00:00ZExperimental Investigations of Rheological Properties of Nile Blend Waxy CrudeMohyadinn , Maysara Eissahttps://repository.sustech.edu/handle/123456789/165662017-07-11T07:04:00Z2013-01-01T00:00:00ZExperimental Investigations of Rheological Properties of Nile Blend Waxy Crude
Mohyadinn , Maysara Eissa
In this paper, laboratory work has been carried out using samples of Sudanese crude (Nile blend) in order to describe its rheological behavior at different flow and thermal conditions, and hence, identifying the temperature dependency of these properties. The rheological properties of Nile blend have been measured using a reliable viscometer connected to a water bath to allow simulating of the pipeline flow temperature. The rheological properties of Nile blend have been correlated with temperatures at different heating treatment conditions. The developed correlations can be utilized in prediction of pressure profiles along Higlig-PortSudan pipeline during its operation condition. The outcome of this paper is useful in performing hydraulic calculations of Higlieg-PortSudan pipeline under non-isothermal operation.
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2013-01-01T00:00:00ZGeoelectric investigation of groundwater potential in Khor Abu Habil drainage basinMohamed , Abd Elhakam EtayebDahab , Mohammed, A.H .Yagoub , Abbas M.https://repository.sustech.edu/handle/123456789/165682017-07-11T07:03:23Z2013-01-01T00:00:00ZGeoelectric investigation of groundwater potential in Khor Abu Habil drainage basin
Mohamed , Abd Elhakam Etayeb; Dahab , Mohammed, A.H .; Yagoub , Abbas M.
Geoelectric investigation for groundwater in Abu Habil water shed, northern Kordofan and it’s environ was done using the Vertical Electrical Sounding (VES) method. Twenty two vertical electrical soundings data were acquired within the locations in the study area Borehole data were also acquired. Electrical resistivity methods are frequently used as investigation tool in groundwater exploration to obtain, details about the location, depth and apparent resistivity of the subsurface layers. Schlumberger Vertical Electrical Sounding (V.E.S) measurements were conducted using a portable ABEM SAS1000 instrument. The acquired data cover a wide range of resisitvity values from 3.0 ?m to more than 5500?m, which generally reflects the variation of resistivity within the sediments and the basement complex. However, the interpretation of vertical electrical sounding is presented in the form of geoelectrical sections. The general trend of these geological sections is east – west and north – south. The depth to the basement and structural contour maps are constructed on the basis of present VES interpretation. The present work can be correlated to previous gravity research which shows low gravity anomalies in Kordofan Province that indicate presence of thick sediments. The aquifer mostly sandstone and, sand with gravel, which is associated with intermediate resistivity range between (25 to 60 ?m) and, the average static water level of about 72 meters in the study area. The study reflects the existence of relatively thick sediments, whereas the thickness does not exceed 25 m in the southwest.
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2013-01-01T00:00:00ZOptimal Speed Control for Direct Current Motors Using Linear Quadratic RegulatorAhmed, Aamir Hashim Obeidhttps://repository.sustech.edu/handle/123456789/165722017-07-11T07:06:10Z2013-01-01T00:00:00ZOptimal Speed Control for Direct Current Motors Using Linear Quadratic Regulator
Ahmed, Aamir Hashim Obeid
Direct Current (DC) motors have been extensively used in many industrial applications. Therefore, the control of the speed of a DC motor is an important issue and has been studied since the early decades in the last century. This paper presents a comparison of time response specification between conventional Proportional-Integral-Derivatives (PID) controller and Linear Quadratic Regulator (LQR) for a speed control of a separately excited DC motor. The goal is to determine which control strategy delivers better performance with respect to DC motor’s speed. Performance of these controllers has been verified through simulation using MATLAB/SIMULINK software package. According to the simulation results, liner quadratic regulator method gives the better performance, such as settling time, steady state error and overshoot compared to conventional PID controller. This shows the superiority of liner quadratic regulator method over conventional PID controller.
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2013-01-01T00:00:00Z