ENGINEERING MATHEMATICS EDUCATION WITH COMPUTER ALGEBRA: THE MATLAB ALTERNATIVE

Computer algebra systems have become an important tool for many engineering and technical professionals. There is a growing need to incorporate such tools into the education of such professionals. This paper discusses these systems and their role within engineering mathematics in higher education. Some advantages and problems associated with computer algebra are highlighted and illustrated using MATLAB

Neural Network Control of a Laboratory Magnetic Levitator

Magnetic levitation (maglev) systems are nowadays employed in applications ranging from non-contact bearings and vibration isolation of sensitive machinery to high-speed passenger trains. In this chapter a mathematical model of a laboratory maglev system was derived using the Lagrangian approach. A linear pole-placement controller was designed on the basis of specifications on peak overshoot and settling time. A 3-layer feed-forward Artificial Neural Network (ANN) controller comprising 3-input nodes, a 5-neuron hidden layer, and 1-neuron output layer was trained using the linear state feedback controller with a random reference signal. Simulations to investigate the robustness of the ANN control scheme with respect to parameter variations, reference step input magnitude variations, and sinusoidal input tracking were carried out using SIMULINK. The obtained simulation results show that the ANN controller is robust with respect to good positioning accuracy

Assessment of Wind Power Potential and Wind Electricity Generation Using WECS of Two Sites in South West, Nigeria

The study was used to analyze the wind characteristics of Shaki (08.40’ N; 03.23’ E; Altitude 457.0 m; Air density 1.1723 kg/m3) and Iseyin (07.58’ N; 03.36’ E; Altitude 330.0 m; Air density 1.1869 kg/m3), two local sites in Oyo State, Nigeria. 21 years monthly mean wind speeds at 10 m height obtained from the Nigeria meteorological department were employed together with the Weibull 2-parameter distribution and other statistics to carry out monthly, seasonal and whole years’ analyses of the sites’ wind profiles for electricity generation. It was found that the whole data spread ranged between 0.9 and 9.1 m/s for the two sites while the 21 years’ average ranged between 3.2 and 5.1 m/s and 2.9 and 4.7 m/s for Shaki and Iseyin sites respectively. Three wind energy conversion systems were employed with the results and it was discovered that, the sites have capacity to generate MWh to GWh of electricity at an average cost/kWh of between € (0.025 and 0.049) and that a turbine with technical parameters of cut-in, cut-out and rated wind speeds of 3.0, 25 and 11.6 m/s is appropriate for the sites

Root Locus-Based Magnetic Levitation System Stabilization: An Undergraduate Control System Design Approach

The subject of control system design has evolved considerably over the years. Although several design techniques and strategies have been adopted to realize control systems that meet a predetermined set of performance criteria, the fundamental problem remains that of developing controllers to adjust the performance characteristics of a dynamic system in order to obtain a desired output behavior. The dynamic behavior of a magnetic levitation system (MLS) of a ferromagnetic ball is compensated in this paper. Consolidating the exposure of undergraduate students to the rudiments of control system design, the paper employs the classical root locus technique to stabilize the system. A combination of analytical and software-based methods is used to design proportional-derivative and phase-lead compensators based on the linearized model of the system. Complete details of the design approach, from modeling and analysis of the plant to computing the values of the controller parameters, are shown. MATLAB scripts for plotting root loci and simulating the system are provided

Voltage Collapse and the Nigerian National Grid

A modern electric power system network (PSN) is typically a large and complex engineering system whose healthy existence is crucial to industrial and socio-economic development of Nations. Voltage instability and collapse contribute to large extent to system collapse or blackouts and it is one of the major concerns for today’s electric power system operations. The Nigerian National grid (NNG) experiences on an average of thirty-five (35) system collapse every year over the past ten (10) years. This paper presents an overview and classification of system collapse on the NNG. Keywords — Voltage collapse, Voltage instability, and Nigerian National Grid (NNG

Constitutive Modeling of Wind Energy Potential of Selected Sites in Nigeria: A Pre-Assessment Model

In this chapter, the authors present the result of a study carried out to develop a pre-assessment model that can be used to carry out a preliminary study on the availability of wind energy resources of a site. 21 years’ (1987 – 2007) monthly average wind speeds for 18 locations in Nigeria were used to create the simple constitutive model. The locations span across the six geopolitical zones of the nation with three stations from each zone. Various statistical procedures were employed in the development of the model. The outcome gave an empirical model, which if employed, will lead to determining the mod- est range of wind energy potential of a site. Further, the results from this model were compared with those from the well-established two-parameter Weibull statistical distribution function and found to be reasonably adequate. Thus with this model, decision on site selection for complete assessment can be made without much rigour

Assessment of wind energy potential of two sites in North-East, Nigeria

The study is used to assess the wind energy potential of Maiduguri and Potiskum, two sites in North-East, Nigeria. 21 years (1987e2007) monthly mean wind data at 10 m height were assessed from the Nigeria Meteorological department and subjected to 2-parameter Weibull and other statistical analyzes. The result showed that average monthly mean wind speed variation for Potiskum ranged from 3.90 to 5.85 m/s, while for Maiduguri, it ranged from 4.35 to 6.33 m/s. Seasonally, data variation between the dry and wet seasons revealed that, the mean wind speed variation for Potiskum ranged from 4.46 (for dry) to 5.16 m/s (for wet), while for Maiduguri it ranged from 5.10 (dry) to 5.59 m/s (wet). The wind power density variation based on the Weibull analysis ranged from 102.54 to 300.15 W/m2 for Potiskum and it ranged from 114.77 to 360.04 W/m2 for Maiduguri respectively. Moreover, Maiduguri was found to be the better of the sites in terms of monthly and seasonal variation of mean wind speed, but they both can be suitable for stand alone and medium scale wind power generation

Differences in the epidemiology of theileriosis on smallholder dairy farms in contrasting agro-ecological and grazing strata of highland Kenya

A prospective cohort study was conducted in five purposively-sampled agro-ecological zone (AEZ)-grazing system strata in Murang’a District, Kenya, between March 1995 and June 1996. The study strata were selected based on a preliminary characterization study to represent the widest range of risks to East Coast fever (ECF) in the District and included zero-grazing and open-grazing farms. In total, 225 calves from 188 smallholder farms were examined from birth to 6 months of age and visited within the first 2 weeks of life and thereafter at bi-weekly intervals for up to 14 visits. The purpose of the study was to characterize the differences in epidemiology (risks of infection, morbidity and mortality) and potential control of ECF between the selected strata. Evidence of Theileria parva infection was assessed by increased antibody levels as measured in an indirect ELISA assay by the percent positivity (PP) of serum samples relative to a strong positive reference serum. Sero-conversion risks of T. parva were highest in the open-grazing strata. Antibody prevalence in adult cattle and ECF morbidity and mortality risks were also highest in open-grazing strata. While different, all five AEZ-grazing strata were considered to be endemically unstable for ECF. East Coast fever challenge was low in all zero-grazing strata and this challenge is likely to remain low due to continuing intensification of smallholder farming in the central highlands. In the open-grazing strata, there was higher challenge and a greater impact of ECF. ILRI publication no.: 99017

Wind Profile Characteristics and Econometrics Analysis of Wind Power Generation of a Site in Sokoto State, Nigeria

This study assessed the viability of wind electricity production at a local meteorological site in Sokoto State, Nigeria. 21 years monthly mean wind speed data at 10 m height obtained from the Nigerian meteorological station were employed to carry out monthly, seasonal, yearly and whole years wind profile characteristics. The data were subjected to the Weibull 2-parameter and other statistical analyses. The econometrics analysis of wind electricity generation from the site was also studied using three wind turbine models of AV 928, V90 and SWT-3.6-107. The outcome showed that the wind speed data ranged from 2.4 to 12.1 m/s while the modal wind speed range was from 6.9 to 9.0 m/s. 98% of the data were found to be greater than 3.0 m/s and better potential exist for wind power generation in the dry season than in the wet. It was also discovered that potential exist for electricity generation of between 60.0MWh and 1.5GWh per month and between 2.1 and 10.8GWh per annum. The least cost of generating 1kWh of wind electricity with the turbine models at the site is estimated to be € 0.014