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Total solar radiation received at various collector inclinations

Oladiran, M.T. (Elsevier Science Ltd, http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/description#description, NaN, 1994)

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Abstract:

Solar energy is finding wide application via several energy-saving devices and systems. Its use, especially in rural areas, can often be limited by the non-availability of complete information on insolation data. In this investigation, both the mean extraterrestrial and terrestrial radiations were calculated for three zones in Nigeria. These zones were assumed to be dependent mainly on the latitude, L. The isotropic model was employed for the computation of the diffuse and ground reflected components of radiation. Consequently, the total insolation was obtained for various inclinations of the collector surface. It was found that three solar energy seasons exist for each zone. For maximum total incident radiation, a different collector inclination is ideal for each solar energy season. However, for all year round applications, a fixed inclination varying between L and (L+10) degrees is recommended.

URI:

http://hdl.handle.net/10311/672

Files in this item: 1

Oladiran_AE_1994.pdf (1.391Mb)

Mean global radiation captured by inclined collectors at various surface azimuth angles in Nigeria

Oladiran, M.T. (Elsevier Science Ltd, http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/description#description, NaN, 1995)

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Abstract:

The use of solar energy is well established for low-grade thermal applications such as water heating and purification. In many of the solar systems, the collector surface located in the Northern Hemisphere faces the true south direction. However, there are occasions in which the radiation received by the collector at various orientations is desirable, such as a collector incorporated with a tracking system. The data for such situations are not available for several solar farms in Nigeria. Consequently, in this study, the average global radiation on flat surfaces was determined for three zones in Nigeria. The total insolation was obtained while the surface azimuth angle was varied between 0° and 75° at 15° intervals. The results are presented for three inclinations of the collector surface, namely L − 10, L, and L + 10 degrees respectively.

URI:

http://hdl.handle.net/10311/671

Files in this item: 1

Oladiran_AE_1995.pdf (1.847Mb)

Energy applications in Botswana

Oladiran, M.T. (Elsevier Science Ltd, http://www.elsevier.com/wps/find/journaldescription.cws_home/269/description#description, NaN, 1995)

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Abstract:	Botswana depends heavily on imported petroleum products for all premium applications. However, there is an abundant reserve of coal and other alternative sources of energy. This paper presents the energy trends and the various options for harnessing the resources. The importance of energy conservation is also discussed.
URI:	http://hdl.handle.net/10311/670

Files in this item: 1

Oladiran_ECM_1995.pdf (958.6Kb)

Some implications of driver training for road accidents in Gaborone

Oladiran, M.T.; Pheko, H. (Elsevier Science Ltd, http://journals.elsevier.com/00014575/accident-analysis-and-prevention/, NaN, 1995)

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Abstract:

In many African countries, including Botswana, the driving schools and instruction given to pupils are uncontrolled. Thus, this paper presents the results of an investigation into the level of professional training offered by the driving schools in Gaborone. A total of 400 randomly selected drivers completed questionnaires on their training, accident records, and L-tests. Male trainee drivers received more instruction than females, and there was some indication that the pass rate on L-tests was lower for female drivers. Also, the pickup van forms the majority of the national vehicle population. It accounts for almost 40% of the accidents but is presently not used for training in the commercial driving schools. It is concluded that the quality of professional instruction in driving schools needs improvement so that learners can be encouraged to take training from these institutes.

URI:

http://hdl.handle.net/10311/669

Files in this item: 1

Oladiran_AAP_1995.pdf (1.673Mb)

Management of waste oil in Botswana and the possibilities of energy recovery from waste oil

Ketlogetswe, C. (University of Botswana, NaN, 1998)

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Abstract:

Since independence, the economy of Botswana has been undergoing a rapid transition from one in which the majority of the people depend on traditional agriculture and pastoralism to one in which formal sector employment predominates. This is partly reflected by rapid increase in vehicle population. Because of these changes,the country started to experience environmental problems. Unfortunately from the time of independence until late eighties, the level of environmental awareness in the country was very low, and therefore waste minimisation and reduction of environmental impact procedures were never in place.To date, many organizations in the country still seem not to be committed to reducing and disposing their wastes in environmentally friendly manner. The need to reconcile development with environmental concern, thus sustainable development, is vital. For the country to achieve that, an introduction of an environmental impact assessment in Botswana is essential, and thus, the main thrust of the current investigation is to determine the level of concern about environmental problems posed by waste engine oil in various organizations in the country. Management of various organizations were interviewed on their methods of waste of engine oil disposal. It was found that the disposal of waste engine oil by many organizations is resulting in serious environmental problems.

URI:

http://hdl.handle.net/10311/675

Files in this item: 1

Ketlogetswe_BJT_1998.pdf (1.028Mb)

Domestic use of electrical energy from wind energy in Botswana

Dimitrova, J.; Slivkov, G. (University of Botswana, Faculty of Engineering and Technology, http://ajol.info/index.php/bjt, April NaN, 1998)

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Abstract:

This paper presents an examination of the possibility of using wind turbines generating electricity for households in the remote rural areas of Botswana. On the basis of theoretical consideration of the wind system generating electricity, and the power demands of a typical Botswana rural household, some types of possible advanced systems are recommended. Comparative information is given about the costs of solar (photovoltatic) and wind power systems. From an analysis of the magnitude and the distribution of the wind in Botswana, conclusions are made about the areas where the wind system for electricity generation could be used during the whole or part of the year.

URI:

http://hdl.handle.net/10311/664

Files in this item: 1

Dimitrova_BJT_1998.pdf (2.728Mb)

Management of waste oil in Botswana and the possibilities of energy recovery from waste oil

Ketlogetswe, C. (University of Botswana, Faculty of Engineering and Technology, http://ajol.info/index.php/bjt, April NaN, 1998)

[more]

[less]

Abstract:

Since independence, the economy of Botswana has been undergoing a rapid transition from one in which the majority of the people depend on traditional agriculture and pastoralism to one in which formal sector employment predominates. This is partly reflected by rapid increase in vehicle population. Because of these changes, the country started to experience environmental problems. Unfortunately from the time of independence until late eighties, the level of environmental awareness in the country was very low, and therefore waste minimisation and reduction of environmental impact procedures were never in place. To date, many organisations in the country still seem not to be committed to reducing and disposing their wastes in environmentally friendly manner. The need to reconcile development with environmental concern, thus sustainable development, is vital. For the country to achieve that, an introduction of environmental impact assessment in Botswana is essential, and thus, the main thrust of the current investigation is to determine the level of concern about environmental problems posed by waste engine oil in various organisations in the country. Management of various organisations were interviewed on their methods of waste engine oil disposal. It was found that the disposal of waste engine oil by many organizations is resulting in serious environmental problems.

URI:

http://hdl.handle.net/10311/659

Files in this item: 1

Ketlogetswe_BJT_1998.pdf (3.285Mb)

Fundamentals of coal gasification technology and its relevance to Botswana coal industry

Khartchenko, N.V.; Oladiran, M.T.; Douglass, G.W. (University of Botswana, http://www.ub.bw, NaN, 1999)

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Abstract:

Coal is plentiful in many parts of the world but its combustion can create severe environmental and aesthetic problems.In the past three decades, the cost of crude oil and natural gas has been unstable and the reserves of these fuels are exhaustible. Other non-conventional energy resources, for example, solar, wind and tidal energy are only making a small contribution to the energy mix in few countries. Consequently, coal still has an important role to play to satisfy the energy demand, especially when it can be converted before combustion to other less environmentally objectionable forms, e.g. coal gas/producer gas. This paper describes the basic principles of coal gasification process and compares the performance of different gasifiers. The fundamentals of the raw gas cleaning methods are presented and experience to date of coal gasification in Botswana is discussed.It seems certain that coal gasification in tanderm with combined cycle power plant will be a principal technique for electricity generation in the next century. The paper recommends that Botswana takes necessary actions to gain maximum advantage from these developments.

URI:

http://hdl.handle.net/10311/710

Files in this item: 1

Khartchenko_BJT_1999.pdf (1.810Mb)

Automobile pollution and the environment

Inambao, F.L.; Mosweu, M. (University of Botswana, NaN, 1999)

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Abstract:

It is widely recognised that air pollution caused by the global rapid increase of automobile traffic is a threat to the environment. With regard to automobiles there are three general areas of concern: urban pollution, especially in highly populated cities with high density of private transport, depletion of the ozone layer and pollution resulting in disturbance of natural environment. Several methods of effective control of automobile emsissions to meet current and future environmental demands are analyzed.

URI:

http://hdl.handle.net/10311/626

Files in this item: 1

Inambao_BJT_1999.pdf (951.9Kb)

Continuing professional development for practicing engineers in developing economies

Oladiran, M. T. (Institute of Electrical and Electronics Engineers (IEEE), http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=13, August NaN, 1999)

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Abstract:

This paper presents the results of an investigation to determine the level of continuing professional development (CPD) for engineers in developing countries. Questionnaires were administered randomly to engineers of different specialties. It was found that CPD for engineers in developing countries seems neglected. Experience and state of the art in the profession are, thus, not usually acquired in an organized fashion. Nevertheless, many of these engineers would support the introduction of continuing professional development at all levels of their careers.

URI:

http://hdl.handle.net/10311/666

Files in this item: 1

Oladiran_IEEETE_1999.pdf (763.3Kb)

PSPICE model of an open-circuit DC shunt machine

Kiravu, C.S.A.M. (University of Botswana, NaN, 2000)

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Abstract:

Computer models are used to replicate the essential performance features of a physical element using convenient modeling and simulation programs. Within SPICE, an acronym for the Simulation Program with Integrated-Circuit Emphasis, a model for the twin-depencence of the machine's open circuit generated e.m.f. on the time-independent flux and machine speed has not been investigated. This paper describes a steady state model of an open circuit DC shunt machine using PSPICE, the PC version of SPICE packaged within the OrCAD programming environment. The model is based on characterization of the generated e.m.f.as field current dependent polymial voltage source whose coeffecients are generated within MATHCAD by applying a linear regression fit on a set of experimental laboratory data points. The simulation results are displayed using the inbuilt graphic postprocessor within PSPICE called PROBE. This results show good replicative model validity within the laboratory range of exciting currents used in the simulative.

URI:

http://hdl.handle.net/10311/621

Files in this item: 1

Kiravu_BJT_2000.pdf (849.3Kb)

A practical model for development of viable engineering education institutions in Africa: with a focus on management and quality of engineering eduation

Mothibi, J.; Kutua, S. (University of Botswana, www.ub.bw, NaN, 2001)

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Abstract:

One of the critical elements that determine the competitiveness of nations is the population density of, and quality of its engineers. This view has been corroborated by researchers such as Biluch (1989), Garelli et al (1997), and Gharajedaghi (1986). Unfortunately most African countries are not performing well on this front. Engineering education institutions, entrusted with the task of improving the measures, find themselves in the uneviable position of attempting to operate in environments in which governments are continuously reducing funding to education in general. The objective of this paper is to develop conceptual models which can aid engineering institution overcome the financial constraints, increase throughput of engineers, and improve the quality of engineering education. The model is based on the cybernetics paradigm and is validated through structural and multiplicative corroboration.

URI:

http://hdl.handle.net/10311/825

Files in this item: 1

Mothibi_BJT_2001.pdf (725.3Kb)

A fourier method of determining the speed fluctuation coefficient of a general slider-crank mechanism

Uziak, J.; Foster, J.D.G. (University of Botswana, NaN, 2001)

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Abstract:

In this paper a method is presented which enables the solution of the equation of motion of the slider-crank mechanism. Expansion of functions into Fourier series is used in this method, whereby the solution of the equation is also Fourier series. This method enables also the determination of the coefficient of speed fluctuation of the slider-crank mechanism. The methods create the basis for an analysis of the influence of various factors, e.g. the working conditions or the construction parameters of the system, on the coefficient of speed fluctuation.

URI:

http://hdl.handle.net/10311/702

Files in this item: 1

Uziak_BJT_2001.pdf (999.6Kb)

Theoritical analysis of an offset single-stroke ram press for sunflower oil extraction

Loukanov, I. A.; Uziak, J. (International Symposium on Theory of Machines and Mechanisms (IFToMM), NaN, 2001)

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Abstract:

The single-stroke ram press machine is widely used for sunflower oil extraction in African countries. It is manually operated, low speed machine constructed on the basis of slider-crank mechanism. The paper presents a detailed theoritical analysis of the mechanism of the linkage system. The analysis is done for different positions of the driving lever (handle) nad other parameters, which influence the performance of the machine. Based on that analysis conclusions on the optimal performance of the mechanism are drawn.

URI:

http://hdl.handle.net/10311/667

Files in this item: 1

Loukanov_IFToMM_2001.pdf (993.1Kb)

Oxide of nitrogen in diesel engines: formation, effects and control

Inambao, F.L.; Mosweu, M. (University of Botswana, NaN, 2001)

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Abstract:

Diesel engines are used in heavy duty applications because of their high effeciency an reliability. However, oxides of nitrogen emissions remain a major concern. In diesel engines, fuel combustion is responsible for a major proportion of oxides of nitrogen emissions. Four sources of the oxides have been identified. The range of possible types of damage to environment and health, as well as effective methods for reduction of oxides of nitrogen, have been analysed.

URI:

http://hdl.handle.net/10311/620

Files in this item: 1

Inambao_BJT_2001.pdf (1.720Mb)

A fourier method of determining the speed fluctuation coefficient of a general slideer-crank mechanism

Uziak, J.; Foster, J.D.G. (University of Botswana, Faculty of Engineering and Technology, http://ajol.info/index.php/bjt, October NaN, 2001)

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Abstract:

In this paper a method is presented which enables the solution of the equation of motion of the slider-crank mechanism. Expansion of functions into Fourier series is used in this method, whereby the solution of the equation of motion is also obtained in the form of Fourier series. This method enables also the determination of the coefficient of speed fluctuation of the slider-crank mechanism. The method creates the basis for an analysis of the influence of various factors, e.g. the working conditions or the construction parameters of the system, on the coefficient of speed fluctuation.

URI:

http://hdl.handle.net/10311/665

Files in this item: 1

Uziak_BJT_2001.pdf (2.257Mb)

A practical model for development of viable engineering education institutions in Africa: With a focus on management and quality of engineering education

Mothibi, J.; Kutua, S. (University of Botswana, Faculty of Engineering and Technology, http://ajol.info/index.php/bjt, October NaN, 2001)

[more]

[less]

Abstract:

One of the critical elements that determine the competitiveness of nations is the population density of, and quality of, its engineers. This view has been corroborated by researchers such as Bilich (1989), Garelli et al (1997), and Gharajedaghi (1986). Unfortunately, most African countries are not performing well on this front. Engineering education institutions, entrusted with the task of improving these measures, find themselves in the unenviable position of attempting to operate in environments in which governments are continuously reducing funding to education in general. The objective of this paper is to develop a conceptual model which can aid engineering institutions overcome the financial constraints, increase throughput of engineers, and improve the quality of engineering education. The model is based on the cybernetics paradigm and is validated through structural and multiplicative corroboration.

URI:

http://hdl.handle.net/10311/663

Files in this item: 1

Mothibi_BJT_2001.pdf (3.126Mb)

Engineering education in Botswana

Foster, J. D. G. (Tempus Publications http://www.ijee.ie/, NaN, 2002)

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Abstract:

The economy of Botswana has grown rapidly since it became independent in 1966, but the population is only 1.7 million. Engineering construction projects are of large scale. The University of Botswana offers engineering degrees in four disciplines, under programs that cover ten semesters. The particular challenges to engineering education in Botswana, as well as the structure of the present and future University of Botswana programs, are described in this paper. Emphasis is placed on a wide range of student individual investigation and design work, and the benefits of a particular project to the student and the program are stated in an illustration.

URI:

http://hdl.handle.net/10311/704

Files in this item: 1

Uziak_IJEE_2002.pdf (769.0Kb)

Towards a systems approach to sustainable development

Kutua, S.; Mothibi, J. (University of Botswana, Faculty of Engineering and Technology, http://ajol.info/index.php/bjt, April NaN, 2003)

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Abstract:

“Sustainable development” as a concept was popularised by a 1987 report of the United Nations World Commission on Environment and Development. The report defined sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. However, from this definition, we cannot ascertain the central intuition of the notion of sustainable development. Failure to do this makes it difficult to derive methods that can be used to formulate effective intervention policies that can enable nations to attain sustainable development. This paper briefly reviews various schools of thought in popular literature on the notion of sustainable development, exposes their weaknesses and develops a holistic notion of sustainable development based on the systems approach.

URI:

http://hdl.handle.net/10311/660

Files in this item: 1

Kutua_BJT_2003.pdf (5.513Mb)

A review of mining taxation in selected SADC countries and Chile

Matshediso, I.B. (University of Botswana, http://www.ub.bw, NaN, 2004)

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Abstract:

Although most SADC countries have or were in the process of liberalizing their legislation and fiscal regimes some member states seemed to levy exorbitant tax rates. SADC members’ states need to note that in designing the optimum tax regime for their respective countries a balance will have to be struck between all the role-players including the investor, government and the community. It is imperative that the tax regimes are designed to provide stability over time and are transparent, easy to administer and internationally competitive. Mining investors view taxation systems as a cost of doing business in a particular country. The effects of taxes can influence company decisions. It is therefore of paramount importance for SADC governments to design tax regimes which will allow the mining sector to get a return on investments which is commensurate with the capital outlay and risk. It is equally important that the mining business should play a key role to the socio-economic developments of the host country in terms of job markets, secondary industries, hospital, schools, skills development and education. The taxation level in SADC countries should be both comparable and competitive with other countries with similar geological potential and this is currently not the case. Chile offered investors the best fiscal regime when compared to the twelve selected SADC countries.

URI:

http://hdl.handle.net/10311/1107

Files in this item: 1

Matshediso_BJT_2004.pdf (1.076Mb)

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