ABSTRACT This study presents a comparative study of two controllers for position and speed control of DC servomotor. PID controller is the most usually used for the position control in DC servomotor. However, the PID controller has some disadvantages such as: the high starting overshoot, slow response for unexpected disturbance and high sensitivity to the controller gain. So, the reasonably design PID controller with computational optimization approach method is proposed to overcome the disad...
General Introduction Concrete is a composite material consisting of aggregates enclosed in a matrix of cement paste including possible pozzolans, has two major components, cement paste and aggregates. The strength of concrete depends upon the strength of these components, their deformation properties, and the adhesion between the paste and aggregate surface [ 1 ]. In recent years, the construction industry has shown significant interest in the use of high strength concrete (HSC), in applica...
Abstract A finite time thermodynamic modelling and simulation of irreversible Otto cycle engines has been developed taking into account the variability of specific heats for working fluid due to temperature variation. The effect of three different parameters on the engine was discussed, which are: the internal irreversibility, the heat losses and the friction losses. A program was developed by using MATLAB software to perform the necessary calculations of thermodynamic model. According to t...
Abstract Temperature rise is of much concern in the short and long term operations of induction machine, the most useful industrial work icon. This work examines induction machines mean temperatures at the different core parts of the machine. The system’s thermal network is developed, the algebraic and differential equations for the proposed models are solved so as to ascertain the thermal performances of the machine under steady and transient conditions. The lumped parameter thermal method...
ABSTRACT It is generally known that the major causes of failure in asphalt pavement is fatigue cracking and rutting deformation, caused by excessive horizontal tensile strain at the bottom of the asphalt layer and vertical compressive strain on top of the subgrade due to repeated traffic loading. In the design of asphalt pavement, it is necessary to investigate these critical strains and design against them. This study was conducted to develop a simplified layered elastic analysis and design ...
ABSTRACT The purpose of this work is to make a contribution to the “Abuja grand design” by proposing a strategy that would facilitate making Abuja feature as a “modern city”. This proposal is entitled “Policy and Regulatory Framework for Fiber Optic Backbone in Abuja”. The main import of the strategy is to network every home and business in Abuja with fiber optics. The city fiber network would serve as a broadband communication medium to provide essentially unlimited and open comm...
ABSTRACT A model of Intelligent Mobile Learning System (IMLS) Using Multi-Agents has been developed and tested in the course of the project reported in this thesis. The IMLS was tailored to match the peculiarities of developing countries especially in terms of limited communications infrastructure and unsteady power supply. Mobile devices communicating over wireless networks are used to provide interaction between learners and teachers anywhere, anytime. In addition to the MultiAgent based IM...
Abstract Deltaic lateritic soils of the Niger delta region of Nigeria differ markedly fiom the other lateritic soils because of some mode of formation related peculiarities. As the most widely used soil materials for road earthworks in the entire region, their continual exploitation based on properties of the more matured and widely studied lateritic soils of the hinterland has met with mixed degrees of failure and success. In this study, samples of this soil material fiom different locations...
ABSTRACT One of the research challenges in cellular networks is the design of an efficient model that can reduce callblocking probability and improve the quality of service (QoS) provided to mobile users. One most important parameter for assessing the quality of service (QoS) in a network is the probability of dropped calls, which has so far not been deeply studied within the context of established cellular networks. Call/packet dropping refers to the event described as the termination of cal...
ABSTRACT The assumed deflection shapes used in the approximate methods such asin the Rayleigh–Ritz method were normally formulated by inspection andsometimes by trial and error, until recently, when a systematic method ofconstructing such a function in the form of characteristic orthogonal polynomials(COPs) was developed in 1985. However, vibrational analyses of plates with all edges free or clamped are much more complicated. This project aims at establishing particular expressions for the ...
ABSTRACT Effective management of large amount and different types of data encountered in daily operations is a major challenge facing academic institutions. Traditional paper based operation is not only costly, but also ineffective. Based on the requirements of the Student Records Office, a student information management system (SIMS) is designed and implemented for Digital Bridge Institute (DBI) in this work. The system is developed to provide DBI with a means to effectively manage its infor...
ABSTRACT The research was conducted to study the possibility of utilizing the waste bricks abundantly available in most parts of Gwer-West Local Government Area of Benue State, particularly Naka, the Local Government capital, as coarse aggregates in structural concrete. Trial mixes were prepared using the crushed burnt bricks known also as brick bats as coarse aggregates only, mixture of crushed bricks and river washed gravel as well as using river washed gravel from River Benue only at varyi...
ABSTRACT With the rise of internet and the explosion of data sources, more and more companies are facing new challenges are facing new challenges that were previously very rare. Those problems concern the storage and the usability of set of data so big and often growing so fast that the usual tools were no more adapted. Moreover the multiplication of data sources and types lead to the problem of storing data that should be considered as unstructured in fixed and structured data models provide...
ABSTRACT For accurate and high rate of lung cancer detection using image processing, an effective preprocessing technique is required. A quality preprocessing technique is necessary to ensure effective removal of noise that interferes with the features of the image and hence improves lung cancer detection rate and accuracy. In this research, an Improved Gaussian Filter (IGF) technique was developed for effective lung image preprocessing. For image segmentation, Otsu thresholding method was us...
Abstract Jatropha Biodiesel was tested in a single cylinder direct-injection, water cooled diesel engine to investigate the operational parameters of a small capacity diesel engine under five engine loads, constant speed test. The jatropha oil is used as a non edible oil to produce the biodiesel. The investigated blends were B0, B25, B50, B75 and B100, where (B#) denotes bio-diesel fuel volume percentage in diesel oil. The jatropha biodiesel was prepared locally in Sudan, specifications of wh...