Browsing by Title
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Mazonde, I.N.; Malete, J.; Sugarman, J. (SRA International Publications. http://www.srainternational.org, NaN, 2007)[more][less]
Abstract: It is globally expected that universities will ensure that policies guiding researchers’ conduct are in place and adhered to. This expectation is not waived in developing countries. Successful implementation of an ethics policy is facilitated by an appropriate national regulatory framework on which to base the argument for compliance. However, it is possible to implement such policies even when a regulatory framework is absent. The University of Botswana implemented a program to increase awareness of research ethics and to manage allegations of research misconduct through a needs assessment and seminars on the Responsible Conduct of Research (RCR). This paper describes this problem, and the success of the program initiated to address it. This program serves as a model for other research institutions in the developing world that may encounter similar challenges. URI: http://hdl.handle.net/10311/634 Files in this item: 1
Mazonde_JRA_2007.pdf (1.666Mb) -
Uys, P.; Kiravu, C.; Mothibi, J. (Emerald http://www.emeraldinsight.com, NaN, 2004)[more][less]
Abstract: This paper reports on the process of developing a blended online engineering course at the Faculty of Engineering and Technology of the University of Botswana. It presents the actual development process in terms of its management, the University's preferred pedagogical approach to student-centred learning and the consequent technological choices and deployment. In that regard, the paper will demonstrate the development of the Electrical principles course (EEB211) focusing attention on what was done, how and what result was achieved. This paper will be a useful reference for all those staff expected to develop their online courses alongside their normal face-to-face lectures. URI: http://hdl.handle.net/10311/460 Files in this item: 1
Uys_CWIS_2004.pdf (702.2Kb) -
Aranibar, J.N.; Anderson, I.C.; Ringrose, S.; Macko, S.A. (Elsvier, www.elsevier.com, NaN, 2003)[more][less]
Abstract: Cyanobacterial soil crusts may be important in arid and semi-arid ecosystems because of their ability to fix atmospheric nitrogen (N2). These crusts are very sensitive to trampling by animals, and their destruction can decrease ecosystem N inputs, affecting the productivity of the region. The objective of this study was to quantify the nitrogen-fixing activity in soil crusts during the wet season in southern African ecosystems using in situ acetylene reduction assays. The average acetylene reduction rates for each site ranged from 88 to 535 nmol m-2 h-1, were highly variable, and were lower than previously reported for other arid areas. All soil samples showed acetylene reduction activity; however, soils with crusts supported higher rates than did "non-crusty" soils under litter, moss, or sand. High values of 15N natural abundance (delta15N) indicated that processes other than N fixation were more important in the crusts than N fixation. For example, coupled and ammonia volatilization or atmospheric deposition of 15N-enriched nitrate or ammonium may have caused shifts in delta15N within the soil crusts. The estimated annual N fixation rates ranged from 8 to 44 g N ha-1 year-1, orders of magnitude lower than values estimated in other studies. The anomalous wet conditions experienced during the year of the study may have increased the temporal availability of soil mineral N and decreased N fixation rates. However, the presence of N fixation activity in all crusts analysed and their ability to survive at high temperature and after long dry periods may provide ecosystem resilience, facilitating ecosystem recovery after severe droughts. URI: http://hdl.handle.net/10311/983 Files in this item: 1
Ringrose_Importance_of_Nitrogen_2003.pdf (2.069Mb) -
Ali, M.M.; Kaelo, P. (Elsevier Ltd. www.elevier.com/locate/amc, NaN, 2008)[more][less]
Abstract: Particle swarm optimization algorithm has recently gained much attention in the global optimization research community. As a result, a few variants of the algorithm have been suggested. In this paper, we study the efficiency and robustness of a number of particle swarm optimization algorithms and identify the cause for their slow convergence. We then propose some modifications in the position update rule of particle swarm optimization algorithm in order to make the convergence faster. These modifications result in two new versions of the particle swarm optimization algorithm. A numerical study is carried out using a set of 54 test problems some of which are inspired by practical applications. Results show that the new algorithms are much more robust and efficient than some existing particle swarm optimization algorithms. A comparison of the new algorithms with the differential evolution algorithm is also made. URI: http://hdl.handle.net/10311/178 Files in this item: 2
Ali_Kaelo_AMC_2008.pdf (3.814Mb)license.txt (1.998Kb) -
Litchev, A.I.; Yanev, K.M. (University of Botswana, NaN, 1999)[more][less]
Abstract: Electromagnets are essentials for the operation of relays, contactors and other electromagnetic apparatus and take part in driving control and protective circuits of industrial processes and power systems. Performance of each electromagnet affects the driving time and the stability of operation of such circuits. This paper examines the improvement of the performance of AC electromagnets by using two diodes. The theoritical analysis lead to expressions for calculating the maximum, average and minimum values of coil-currents. Due to the electromagnetic processes in the coil, the current becomes pulsating but unidirectional and better force-gap characteristics are achieved. Consideration are made for reduction of the mass ferromagnetic and copper materials in the electromagnets and for decreasing teh responding time. URI: http://hdl.handle.net/10311/683 Files in this item: 1
Litchev_BJT_1999.pdf (924.8Kb) -
Sahu, B.K.; Mathur, S.; Kemsley, B. (University of Botswana, NaN, 2004)[more][less]
Abstract: The national road network continues to play a fundamental and catalytic role in the promotion of social and economic development of Botswana. However, a combination of adverse climatic and geological factors, such as scarcity of conventional road building materials, near absence of a non saline surface water, and climatic extremes have dictated the need for innovative engineering approaches to highway design, construction and maintenance. In recent years application of fly ash has been considered in road construction with great interest. Fly ash is a pozzolanic material, which in the presence of water combines with lime to produce a cementetious material with excellent structural properties. Attempts have, therefore, been made at Botswana Roads Department in collaboration with University of Botswana to explore the feasibility of utilizing fly ash alone to improve the physical and strength characteristics of locally available non-standard marginal materials. The results indicate that with the addition of fly ash plasticity dereases while California Bearing Ration (CBR) increases for calcrete and other locally available marginal materials for road construction. With appropriate amount of fly ash and an adequate curing the material can be improved to meet the requirement of base and sub-base coarse. URI: http://hdl.handle.net/10311/644 Files in this item: 1
Sahu_BJT_2004.pdf (606.5Kb) -
Pansiri, N.O. (Elsevier Ltd. http://www.sciencedirect.com, July NaN, 2008)[more][less]
Abstract: This paper is part of a study that assessed the level of commitment of primary schools of remote area dwellers (RADs) to basic education between October 2004 and April 2005. The research question focused on the level of commitment of schools to universal basic education, school–community partnership in school governance and parental involvement in the way the curriculum was delivered. Questionnaire and interviews were used. The results show a significant relationship between teachers’ perceptions and variables such as district, qualifications, age, location, and experience. There is consistency between teachers’ perceptions and children's academic performance. It has been found that learner achievement in RADs schools is low and that parents are not actively involved in their children's education due to the policy environment and school management practices. URI: http://hdl.handle.net/10311/521 Files in this item: 1
Pansiri_IJED_2008.pdf (1.181Mb) -
Ogwu, F.J.; Talib, M.; Aderounmu, G.A. (Science Publications, http://www.scipub.org/scipub/c4p.php?j_id=JCS, NaN, 2007)[more][less]
Abstract: This study presents a technique for improving the quality of service (QoS) guarantee in an ATM network. In the proposed model, it was assumed that high priority traffic have been allocated a switch resource to guarantee a given QoS and low priority cells are allowed to enter the buffer, to improve the exploitation of reserved resources. The proposed technique was backed up with an exact analytical model for evaluating the cell loss probability of high and low priority cells. The performance of the proposed model was evaluated using C++ programming language. The results of the simulation shows that the loss probability of both high and low cells reduces as the buffer capacity increase and that the performance of high priority cell is better than that of low priority cell. URI: http://hdl.handle.net/10311/818 Files in this item: 1
Ogwu_JCS11_2007.pdf (556.8Kb) -
Ngowi, A.B. (Elsevier, NaN, 1997)[more][less]
Abstract: The traditional developed earth as one of the most important construction materials by taking cognizance of the strength requirements, durability of resulting structures and the environmental concern in processing and using the material. Overthe years, however, modern earth construction has replaced the traditional methods. Unfortunately,these methods are also accompanied by high energy consumption and environmental degradation.This paper examines the methods of improving earth construction in two major villages in Botswana.Tests with different stabilizers showed that only certain proportions were effective and it was concluded that the traditional earth construction may be improved by using certain ratios of cement and lime as stabilizers. URI: http://hdl.handle.net/10311/606 Files in this item: 1
Ngowi_CBM_1997.pdf (968.2Kb) -
Molomo, M.G. (Pula: Botswana Journal of African Studies, NaN, 2000)[more][less]
Abstract: Electoral systems are manipulative instruments that determine how elections are won and lost. Botswana is widely regarded as a frontrunner in democratic politics, but the electoral system that it operates has been wanting in some respects. Tthe First-past-the-post system has helped to consolidate democratic practice, and also provides for an effective link between Members of Parliament and their constituencies, but empirical evidence suggests that it is the least democratic electoral system. Its winner-take-all practic distorts electoral outcomes, and often produces minority governments. The article proceeds to discuss proportional representation (PR) and semi-proportional representation, and outlines their strengths and weaknesses. The paper concludes that since both the FPTP system and PR systems have inherent limitations, the best system would be one that draws on the best aspects of each system. The anicle recommends a variation of the Mixed-Member Proportionality system. URI: http://hdl.handle.net/10311/900 Files in this item: 1
Molomo2_PBJAS_2000.pdf (880.6Kb) -
Mwikisa, P. (University of Botswana, Department of English, http://www.ub.bw, NaN, 2008)[more][less]
Abstract: The paper offers a reading of Shakespeare's the Tempest, Othelo and Titus Andronicus that sees the plays' black characters as disporic protagonists seeking alternative constructions of difference from those that are demanded by the dominant white patriarchal culture. The paper deploys two fairly well-known strategies for non-canonical readings of canonical texts. Firstly, the apocryphal approach offers an account of the significance of the fact that details of the origins of the black characters in the plays seem suppressed. Secondly, drawing on post colonial discourse of the body, the paper reads the characters themselves as texts or spaces in which conflicting discourses can be written and read.I argue that reading the plays this way helps us to understand the struggles of diasporic characters as they attempt to inscribe their presence in the dominant cultures of the west and also to see in their struggles reflections of the trajectory of texts from marginalized communities in the era of global multinational capitalism. URI: http://hdl.handle.net/10311/853 Files in this item: 1
Mwikisa_MJLL_2008.pdf (3.718Mb) -
Kiker, G.; Munoz-Carpena, R.; Wolski, P.; Cathey, A.; Gaughan, A.; Kim, J. (Inderscience, http://www.inderscience.com, NaN, 2008)[more][less]
Abstract: In this paper, we present a review and conceptual design to integrate hydrological/ecological models, global uncertainty and sensitivity analysis, integrative modelling and decision analysis for complex and adaptive transboundary challenges. The research uses the transboundary issues within the Okavango River basin, a shared water resource among the nations of Angola, Namibia and Botswana, as an example for constructing these integrated tools. The objective of this paper is to present a design that integrates a set of tools that builds systematically on past basin modelling research to incorporate the inherent uncertainty within the system and its application for answering practical management questions. URI: http://hdl.handle.net/10311/864 Files in this item: 1
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Sebudubudu, D. (Made Plain Commucation, NaN, 2008)[more][less]
Abstract: Botswana has since 1965 held nine successive multi-party elections, making it Africa's longest running democracy. Although elections are high tension events, they have not sparked violence in Botswana- a rare feature in the African continent. This chapter provides an assessment on how the Independent Electoral Commission (IEC) contributes to the national integrity system of the country. This chapter examines the role and structure of the commission; the resources it accounts for; its mechanisms for redress, as well as its relationship with other national integrity pillars. The aim of this assessment is to provide an overview of the laws that establish and govern the commission, and the practical situation. URI: http://hdl.handle.net/10311/592 Files in this item: 1
Sebudubudu_TACB_2008.pdf (1.331Mb) -
Ringrose, S.; Vanderpost, C.; Matheson, W.; Wolski, P.; Huntsman-Mapila, P.; Murray-Hudson, M.; Jellema, A. (Elsevier Ltd; www.elsevier.com/locate/jaridenv, January NaN, 2007)[more][less]
Abstract: This work seeks to determine whether riparian woody plant variables respond to drying and salinity regimes in the semi-arid distal Okavango Delta, northern Botswana. Structural and compositional variables were obtained from 47 field sites. Mapping using satellite imagery illustrated differences in the character of riparian zones in terms of species composition and provided data on flood frequency. Salinity data plots show increases downstream. Results imply that woody plant variables respond to desiccation-driven change due to water-table lowering (reduced recharge) and increased salinization through distinct changes in tree and shrub height, plant density and species richness. In the wetter, intermediate distributaries, key biotic indicators of ecosystem change comprise structural variables such as decreases in canopy cover per cent and tree height and increases of shrub height, which are indicative of mainly ground-water declines. Biotic indicators in the less frequently flooded receiver channels comprise plant density and species richness increases involving mainly brackish ground-water-tolerant and dryland species which are indicative of both ground-water declines and/or salinization. These indicators could provide useful parameters for use in long- and short-term monitoring aimed at assessing desiccation-driven change in different parts of the Okavango Delta and possibly other semi-arid wetlands. The indicators are important as a less-expensive alternative to drilling as a means of verifying ground-water declines and/or salinization. URI: http://hdl.handle.net/10311/161 Files in this item: 2
license.txt (1.998Kb)Ringrose_et_al_JAE_07.pdf (1.322Mb) -
Malumbela, G.; Moyo, P.; Alexander, M. (Elsevier http://www.elsevier.com/locate/conbuiltmat, NaN, 2011)[more][less]
Abstract: Corrosion crack widths are often used by structural engineers in the field to predict level of steel corrosion as well as residual load-bearing capacities of corroding RC structures. This paper presents further work on this matter but with focus on corrosion crack patterns and how they affect rate of crack widening. It is based on results from a research where 17 quasi-full-scale (153 254 3000 mm) RC beams were corroded under various levels of sustained loads. The rate of widening of corrosion crack widths was found to be very much dependent on crack patterns. Deformation of cover concrete under each crack pattern was discussed. It was found that at maximum crack widths below 0.6 mm, the majority of beams exhibited nearly similar crack patterns as well as rate of widening of corrosion cracks. A mass loss of steel of 1% corresponded to a maximum crack width between 0.14 and 0.22 mm. At large crack widths (>0.6 mm), various beams exhibited very different rates of crack widening. It was shown that at crack widths above 0.6 mm, to be conservative an increase in mass loss of steel of 1% corresponded to corrosion crack widening of 0.02 mm. URI: http://hdl.handle.net/10311/676 Files in this item: 1
Malumbela1_CBM_2010.pdf (1.399Mb) -
Banda, A.; Mubyana-John, T.; Taylor, J.E. (Global Science Books, http://www.globalsciencebooks.info/, NaN, 2011)[more][less]
Abstract: The influence of burning on soil microbial dehydrogenase activity, nitrogen content and fungal population along the Boro route in the Okavango Delta was assessed in the flood and dry seasons. Soil samples from the burnt plots and the adjacent control un-burnt plots were cultured on agar plates using dilution methods. Fusarium spp. were dominant while Aspergillus species were low in burnt plots. The other fungi such as Drechslera sp., Exophiala jeanselmmei, Penicillium compactum and Chrysosporium merdarium were only in the burnt plots as compared to unburnt control plots. However, fungal diversity and soil dehydrogenase activity reduced after 6 months of burning showing significant increase in Chrysosporium merdarium in almost all the burnt plots. The influence of burning on soil nitrogen was insignificant instead flooding had a stronger influence on nitrogen content than burning. The results indicate that burning increased fungal diversity and biomass, however, reduces overall microbial enzyme activity after burning without influencing soil nitrogen and pH. URI: http://hdl.handle.net/10311/919 Files in this item: 1
Mbuyana_AJPSB_2011.pdf (220.0Kb) -
Phibion, O.S. (IJSRE, http://www.ijsre.com, June NaN, 2012)[more][less]
Abstract: This article examines choral contests in Botswana’s music education. Choral contests have been conducted for many years in Botswana and predate the introduction of formal music teaching in schools. These early contests were often annual choral competitions (tonic sol-fa notation) and were organized through the Botswana Teachers Union or community organizations such as churches. These early choral competitions in fact laid a foundation for formal music teaching in schools. Data for this study was collected through the researcher’s participatory observation as a college choir conductor, a community choir conductor and a competition adjudicator. Rather than empirical research, this article is based on a critical argument about issues the author has experienced. At the time of writing this article, there has been very little to no documentation of Botswana choral music. URI: http://hdl.handle.net/10311/1037 Files in this item: 1
Phibion_IJSRE_2012.pdf (1.046Mb) -
Magogwe, J.M. (University of Botswana, Department of English, http://www.ub.bw, NaN, 2008)[more][less]
Abstract: This research seeks to examine the role that context or learning situation plays in strategy choice by comparing the strategy patterns of a private English medium secondary and a government secondary school in Botswana. More specifically, the main ofjectives of this study are to, firstly, investigate whether the type of school influences the choice of language learning strategies of its students: secondly, to find out whether private English medium secondary school students use more strategies than government secondary school in Botswana: and, thirdly, to explore the role played by gender on the choice of language learning strategies. Form four students from oneprivete English medium senior secondary school and one government senior secondary completed the strategy inventory for language learning (SIILL). The data was analysed using descriptive statistics to calculate means and standard deviations of strategies and inferential statistics such as ANOVA to establish the relationships between group and individual strategies. The findinds of this study showed that the choice of strategies was not greatly influenced by the type of school from which the student came. However, this study found that government school students relied more on the use of dictionaries. On the other hand, private English medium students volunteered to look for conversation partners in order to get practice in speaking English. In relation to gender, the findings of this studyconfirmed other previous findings that female students use more language learning strategies than do male students. URI: http://hdl.handle.net/10311/859 Files in this item: 1
Magogwe_MJLL_2008.pdf (3.125Mb) -
Mubyana, T.; Krah, M.; Totolo, O.; Bonyongo, M. (Journal of Arid Environments. http://www.elsevier.com/wps/find/journaldescription.cws_home/622855/description#description, NaN, 2003)[more][less]
Abstract: The effect of flooding on soil total nitrogen, phosphorus and microbial population in different vegetation zones (floodplain, island and woodland) and profile depth (0?1, 0?5, 2?0, 3?0, 4?0 and 5?0m) of the Okavango Delta was studied from February to July 1999. Total nitrogen significantly differed with soil profile depth, moisture regime and months. In the woodlands, insignificant total nitrogen was detected at all depths except at 0?1m, where 0?03% and 1?17% were detected in February and March, respectively. In the island samples, only 0?05% was detected at 4m in February. Nitrogen in the floodplain samples was concentrated in the A1 horizon where 0?12%, 0?61% and 0?03% were detected in February, March, and May, respectively. Organic phosphorus significantly differed with vegetation zone but not with months and depth. Although organic phosphorus was low (0?02–0?52%) at all sites, it was liberally distributed throughout the profiles. On the island, actinomycetes were only detected up to 2m in February and up to 3m in July. Fungi concentrated in the top 0?5m (103–105). In both the floodplain and island samples, bacteria concentrated in the upper 3m. However, after May, populations decreased significantly. In the floodplain, significant actinomycetes populations were only detected in the upper 0?5m. Generally, organic phosphorus showed positive correlations with fungal populations. This study indicates that these soils are low in total nitrogen and phosphorus. URI: http://hdl.handle.net/10311/293 Files in this item: 1
Influence of seasonal flooding.pdf (3.953Mb) -
Dikinya, O.; Hinz, C.; Aylmore, L.G. (Csiro, http://www.publish.csiro.au/nid/84.htm, NaN, 2007)[more][less]
Abstract: The paper examines the effects of electrolyte concentration and sodium adsorption ration (SAR) on the relative saturated hydraulic conductivity (RHC) and the ionic behaviour of calcium (Ca) and sodium (Na) ions in the Na-Ca echange complex. Batch binary exchange and saturated column transport experiments were carried out to quantify these effects using agricultural Balkuling soil and mining residue. Generally, RHC has been found to decrease with time, with increasing SAR and with decreasing electrolyte concentration. The more rapid decrease in RHC in the mining residue, particularly at the lowest concentration (1 mmol/L), was consistent at all SAR values. The decreases in RHC were likely to be caused by partial blocking of pores by dispersed clay particles, as evidenced by the appearance of suspended clay particles in the effluent during leaching. Significant differences in RHC were abserved in the passage of fronts of decreasing electrolyte concentration for CaCl2 and SAR 15 solutions through the soil columns. These differences were attributable to structural alterations (slaking) of the media and the nature of the particles released and mobilised within the porous structure at a given point in the column. Measurements at the critical threshold concentration and turbidity increase in SAR to 15 is initially accompained by erractic RHC, presumably due to the break up of soilaggregates under the increased swelling forces. The less coherent mining residue soil was substantially more vulnerable to blockage of pores than the Balkuling soil in which clay particles are likely to be more readily mobilised, and hence available to re-deposit and occlude the matrix pores. URI: http://hdl.handle.net/10311/312 Files in this item: 1