Browsing by Title
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Cao, Y.; Allameh, S.; Sethiaraj, S. (Elsevier, NaN, 2006)[more][less]
Abstract: This paper presents the results of nanoindentation experimental studies of the contact-induced deformation in Au and Ag thin films. The paper examines the effects of film thickness and substrate deformation restraint on the mechanical properties of electron beam (e-beam) deposited Au and Ag films. Following a brief description of film microstructure, surface topography, and contact-induced pile-up deformation, film mechanical properties (hardness and Young’s modulus) were determined using nanoindentation techniques. The indentation size effects (ISE) observed in films with different thicknesses were explained using a mechanism-based strain gradient (MSG) theory. The intrinsic film yield strengths and hardnesses extracted from the MSG theory are shown to exhibit classical Hall–Petch dependence on the inverse square root of the average film grain size. Displacement bursts were also found to occur in Ag films at indentation load levels of 100 N. These were attributed to the initial onset of dislocation slip activity, when the shear stress exceeds the estimated theoretical shear strengths of the materials. URI: http://hdl.handle.net/10311/537 Files in this item: 1
Nanoindentation measurements.pdf (1.173Mb) -
Chilisa, B. (Taylor & Francis, http://www.tandf.co.uk/journals, NaN, 2002)[more][less]
Abstract: The article critiques pregnancy policies in the education systems in sub-Saharan Africa. Policies discussed are divided into expulsion, re-entry and continuation policies. Arguing from the standpoint of theories of oppression, it is postulated that expulsion policies symbolise direct violence against girls who become pregnant and are more common in those countries with poor human rights records. Continuation and re-entry policies are prevalent in countries that have ratified the Convention on the Elimination of all Forms of Discrimination Against Women and the Convention on the Rights of Children. It is argued that re-entry policies also violate girl mothers’ right to education through a retreat ideology that requires temporary withdrawal of the pregnant girl from school. Moreover, gender inequalities are built into the policies and supported by traditional and institutional ideologies that make re-entry of the girl mother into the school difficult. The Botswana re-entry policy is reviewed to illustrate difficulties in the readmission of girl mothers to school. URI: http://hdl.handle.net/10311/1040 Files in this item: 1
Chilisa_GE_2002.pdf (1.431Mb) -
Chilisa, B. (Routledge, http://www.informaworld.com, March NaN, 2002)[more][less]
Abstract: The article critiques pregnancy policies in the education systems in sub-Saharan Africa. Policies discussed are divided into expulsion, re-entry and continuation policies. Arguing from the standpoint of theories of oppression, it is postulated that expulsion policies symbolise direct violence against girls who become pregnant and are more common in those countries with poor human rights records. Continuation and re-entry policies are prevalent in countries that have ratified the Convention on the Elimination of all Forms of Discrimination Against Women and the Convention on the Rights of Children. It is argued that re-entry policies also violate girl mothers' right to education through a retreat ideology that requires temporary withdrawal of the pregnant girl from school. Moreover, gender inequalities are built into the policies and supported by traditional and institutional ideologies that make re-entry of the girl mother into the school difficult. The Botswana re-entry policy is reviewed to illustrate difficulties in the readmission of girl mothers to school. URI: http://hdl.handle.net/10311/835 Files in this item: 1
Chilisa_GE_2002.pdf (789.0Kb) -
Meck, M.L.; Masamba, W.R.L.; Atlhopheng, J.; Ringrose, S. (Elsevier Science Ltd, http://www.elsevier.com/locate/pce, NaN, 2011)[more][less]
Abstract: The objective of the study was to investigate the role played by the natural environment in protecting the transboundary Save River from the impacts of metals derived from phosphate mining at Dorowa. The study is a follow up study from a previous one that noted that there is natural attenuation at Dorowa. Water and sediment samples were collected in the Save River and the streams that drain the Dorowa dumps. Inductively coupled plasma mass spectrometry (ICP–MS) was used to analyze the cations (Na+, K+, Ca2+, Mg2+, Cu2+, Co2+, Fe2+, Ni2+, Zn2+, Pb2+, Sn2+, Mn2+, Cd2+) in the samples. Major anions Cl , SO2 4 and NO 3 were analyzed by standard chromatography whilst CO2 3 and HCO 3 were determined by titration. pH was measured on site. Geochemical modeling of the water composition was conducted with Visual Minteq. The results show that natural attenuation is being achieved through precipitation of solids from the water and subsequent deposition onto the sediments. Six of the metals are almost completely precipitated (Cu 99.99%, Fe 99.39%, Ni 91.24%, Pb 99.87%, Sn 99.99% and Zn 88.66%). However Mn, Co and Cd remain in solution. Thus the natural environment is protecting the Save River which is a transboundary river from the impacts of mining through precipitation of the metals. Users downstream of Dorowa mine are therefore not being affected by mining pollution. This study demonstrates that besides being a legitimate and important user of water, the natural environment can also play a significant role in protecting water quality by attenuating metals naturally. By analyzing costs incurred in several places where alternative methods are employed to remediate metal related pollution the study concludes that natural remediation at Dorowa is saving the nation in environmental costs. Therefore the paper advocates for appreciation of the role that the natural environment plays in protecting ecosystems from the impact of human developments and environmental costs. Subsequently, this calls for recognition of natural environment’s role in water resources management for the sustenance of ecosystems and peoples livelihoods. URI: http://hdl.handle.net/10311/963 Files in this item: 1
Atlhopheng_PCE_2011.pdf (630.3Kb) -
Murty, V.R.K.; Karunakara, N. (Elsevier, www.elsevier.com/locate/radmeas, NaN, 2008)[more][less]
Abstract: Studies on concentrations of primordial radionuclides in soil samples of Botswana were carried out. Measurements were made by gamma spectrometry employing a 41% relative efficiency HPGe detector. The activity of 226Ra was found to vary in the range 6.1–97.4 Bq kg 1 with a mean value of 34.8 Bq kg 1, 232Th in 7.4–110.0 Bq kg 1 with a mean value of 41.8 Bq kg 1 and that of 40K between 33.5 and 1085.7 Bq kg 1 with a mean value of 432.7 Bq kg 1 in surface soils. Existence of strong correlations in the distributions of these radionuclides indicates that an individual result for any one of the radionuclide is a good predictor of the concentration of the other. The mean value of effective dose, due to the 238U series, 232Th series and 40K in soil, was 0.07 mSV. The results of the present study are compared with the literature values reported for other normal background regions of the world and discussed. URI: http://hdl.handle.net/10311/493 Files in this item: 1
Murty2008SoilSamples.pdf (782.0Kb) -
Hambira, W.L. (Elsevier, http://www.elsevier.com/wps/find/journaldescription.cws_home/413/description#description, NaN, 2007)[more][less]
Abstract: Natural Resource Accounting (NRA) has become an important environmental/natural resources management tool in recent years. It provides information on stocks of a resource available at a particular point in time and what activities the resource is being used for. The conventional System of National Income Accounts (SNA) normally does not capture the cost of depletion, degradation or pollution of natural resources. This encourages unsustainable use of natural resources since the costs are not reflected when assessing the country’s economic performance or development progress. NRA is thus an attempt to integrate environmental issues into the conventional national accounts. The water sector is one sector that could greatly benefit from this natural resource management tool. Botswana has adopted NRA as a natural resource management tool and has so far developed accounts for minerals, livestock and water. The focus of this paper is on Water Accounting (WA) in relation to Integrated Water Resources Management (IWRM). IWRM is concerned with coordinated development and management of water in order to maximise economic and social welfare without compromising the sustainability of ecosystems. WA helps fill data gaps since it provides the required information for IWRM to be achieved. The aim of this paper therefore is to evaluate the Water Accounts of Botswana Report of 2006 to determine the extent to which it can contribute to integrated water resources management. The paper is based on literature review and the results show that: the available water stocks vary depending on rainfall patterns, well fields are over utilised, there has been growth in consumption, and more than 80% of the waste water produced is not being put to use. These results calls for changes in policies, role of institutions and practices pertaining to water resources management which is what IWRM is all about hence the paper concludes that indeed WA can contribute to the realisation of IWRM. URI: http://hdl.handle.net/10311/283 Files in this item: 1
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Batibo, H.M.; Kopi, M.M. (University of Botswana, Department of English, http://www.ub.bw, NaN, 2008)[more][less]
Abstract: The aim of this study is to investigate sex-related euphemisms in Setswana. Although sex matters, as embarrassing phenomena, are not usually talked about in Setswana communities, they have recently been brought to the open by the incidence of the HIV/AIDS pandemic. The assumption in this study is therefore that, with more open discourse of sex-related matters in Botswana, more euphemisms have been created to camouflage the embarrassing nature of the various referents in this field. The sex-related matters include private parts, sexual activities, sexual secretions, sexual diseases and related phenomena. This study describes the nature, origin, and types of these euphemisms and considers their place and role in the social interaction of the people of Botswana. URI: http://hdl.handle.net/10311/852 Files in this item: 1
Batibo_MJLL_2008.pdf (2.902Mb) -
Malumbela, G.; Sebusang, N. (Faculty of Engineering and Technology, University of Botswana, www.ub.bw, April NaN, 2011)[more][less]
Abstract: Concrete is the widely used construction material worldwide. Therefore, for structural safety as well as to provide economic design, it is essential to understand well, its performance. Whilst in most developed countries extensive research has been done to characterise concrete, little is known about the performance of concrete in Botswana. This paper reviews previous work carried out in other countries to assess performance of their concrete. Focus is on influence of aggregate type. It is shown from the review that there is great need to study influence of aggregate on performance of concrete in Botswana, particularly comprehensive strength. A brief description of the needed research is outlined. URI: http://hdl.handle.net/10311/889 Files in this item: 1
Malumbela_BJT_2011.pdf (934.5Kb) -
Cailteux, J.L.H.; Kampunzu, A.B.; Lerouge, C. (Elsevier www.elsevier.com/locate/gr, NaN, 2007)[more][less]
Abstract: Rocks of the Neoproterozoic Mwashya Subgroup (former Upper Mwashya) form the uppermost sedimentary unit of the Roan Group. Based on new field and drill hole observations, the Mwashya is subdivided into three formations: (1) Kamoya, characterized by dolomitic silty shales/ siltstones/sandstones and containing a regional marker (the “Conglomerate de Mwashya” bed or complex); (2) Kafubu, formed by finely bedded black carbonaceous shales; and (3) Kanzadi, marked by feldspathic sandstones. Rocks of the Mwashya Subgroup are overlain by the Sturtian age Grand Conglomérat diamictite (equivalent to the Varianto/Brazil and Chuos/Namibia diamictites), and conformably overlie rocks of the Kansuki Formation (former Lower Mwashya), a carbonate unit containing volcaniclastic beds. New geochemical data confirm the continental rift context of this magmatism, which is contemporaneous with rift-related volcanism of the Askevold Formation (Nosib Group, Namibia). A gradational lithological transition between rocks of the Kansuki and the underlying Kanwangungu Formations, and similar petrological composition of these two formations, support the hypothesis that the Kansuki is the uppermost unit of the carbonate-dominated Dipeta/Kanwangungu sequence, and does not form part of the Mwashya Subgroup. Base metal deposits, mostly hosted in rocks of the Kansuki Formation, include weakly disseminated early-stage low-grade Cu–Co mineralisation, which was reworked and enriched, or initially deposited, by metamorphic fluids associated with the Lufilian orogenic event. URI: http://hdl.handle.net/10311/399 Files in this item: 1
Kampunzu2007Neoproterozoic Mwashya.pdf (2.801Mb) -
Masoso, O.T. (Elsevier http://www.linkinghub.elsevier.com/retrieve/pii/S0378778808000923, NaN, 2008)[more][less]
Abstract: This paper presents the findings of a case study with building simulation using EnergyPlus dynamic thermal simulation software, in which wall insulation was varied together with cooling set-point temperature in a hot and dry climate of Botswana. Against the established norm that adding wall insulation reduces annual fuel consumption, it is shown in this paper that this is not always the case: there are instances where adding wall insulation directly increases annual fuel consumption. Initial cost of insulation aside, as the cooling set-point temperature is gradually increased, the building switches from an ‘‘insulation reduces cooling load’’ to an ‘‘insulation increases cooling load’’ behaviour. In other words, the well established knowledge that ‘‘the lower the u-value the better’’ gets overridden by ‘‘the higher the u-value the better’’. We termed this a ‘‘point of thermal inflexion’’. Simple graphical demonstration of the existence of this point is presented in the paper. According to the findings, design engineers and building economics related professionals who quantify investment on insulation can get disastrous results if they assume that all buildings behave pro-insulation since a building may behave anti-insulation. URI: http://hdl.handle.net/10311/673 Files in this item: 1
Masoso_EB_2008.pdf (867.2Kb) -
Chilisa, B. (National Council on Measurement in Education. http://www3.interscience.wiley.com, December NaN, 1999)[more][less]
Abstract: The study briefly looks at the new developments in the national examination system in Botswana. With this new system, the government opted for a criterion-referenced testing (CRT) model for primary and junior secondary schooling national examinations. URI: http://hdl.handle.net/10311/1009 Files in this item: 1
Chilisa_EMIP_1999.pdf (365.9Kb) -
Marobela, M. (Emerald Group Publications, www.emeraldinsight.com, NaN, 2006)[more][less]
Abstract: Capitalist transformation of the public sector is global phenomenon that affects many countries. This paper seeks to examine recent public sector reforms introduced by the Government of Botswana to improve civil service performance. The underlying political philosophy behind the change in the public sector is explored by relating neoliberal ideology which is driving the reform agenda to the discourse of new public management (NPM) URI: http://hdl.handle.net/10311/858 Files in this item: 1
marobela_IJSE35_2006.pdf (1.480Mb) -
Ntshwene, K.; Kashiwagi, J.; Kashiwagi, D. (Royal Institute of Chartered Surveyors http://www.rics.org/site/download_feed.aspx?fileID=5042&fileExtension=PDF, NaN, 2009)[more][less]
Abstract: The traditional contracting/delivery system in Botswana, introduced by the US, UK, and European educators, consultants, and practitioners, has not been working well in Botswana. The poor project delivery system results have forced the organization of a new group, the Government Implementation Coordination Group (GICO) to attempt to solve the problems. In the fall of 2008, the University of Botswana (UB), through the US State Department sponsored Fulbright program, brought professor Kashiwagi, and the best value Performance Information Procurement System (PIPS) technology, the Information Measurement Theory (IMT), and the Industry Structure Analysis to the UB project management section. This paper proposes that the client’s professional representative requires a new, more effective role. The role includes using performance information, transforming the client’s expectations into a design/construction intent by using expert vendors, ensuring the vendors manage and minimize the risk that they do not control, outsourcing the technical responsibilities, and doing quality assurance instead of quality control. This paradigm will minimize project risk, maximize project value, and increase the professionalism of project management, construction management, and quantity surveyors. These concepts will be tested on three test projects in Botswana. URI: http://hdl.handle.net/10311/473 Files in this item: 1
Ntshwene_COBRA_2009.pdf (1.344Mb) -
Makgala, Christian John (Routledge (Taylor and Francis) http://www.routledge.com, NaN, 2006)[more][less]
Abstract: This article is a modest sketch of the historical background to the phenomenon of xenophobia, with which policymakers in Botswana are grappling in the early twenty-first century. It is not, however, a historical treatise on xenophobia. Furthermore, it is acknowledged that scholarship on xenophobia is recent, being a post-liberation development in Southern Africa. URI: http://hdl.handle.net/10311/510 Files in this item: 1
Makgala_AHR_2006.pdf (1.805Mb) -
Aranibar, J.N.; Otter, L.; Macko, S.A.; Feral, C.J.W.; Epstein, H.E.; Dowty, P.R.; Eckardt, F.; Shugart, H.H.; Swap, R.J. (Blackwell Publishing, January 1, 2004)[more][less]
Abstract: Nitrogen (N) cycling was analyzed in the Kalahari region of southern Africa, where a strong precipitation gradient (from 978 to 230mm mean annual precipitation) is the main variable affecting vegetation. The region is underlain by a homogeneous soil substrate, the Kalahari sands, and provides the opportunity to analyze climate effects on nutrient cycling. Soil and plant N pools, 15N natural abundance (d15N), and soil NO emissions were measured to indicate patterns of N cycling along a precipitation gradient. The importance of biogenic N2 fixation associated with vascular plants was estimated with foliar d15N and the basal area of leguminous plants. Soil and plant N was more 15N enriched in arid than in humid areas, and the relation was steeper in samples collected during wet than during dry years. This indicates a strong effect of annual precipitation variability on N cycling. Soil organic carbon and C/N decreased with aridity, and soil N was influenced by plant functional types. Biogenic N2 fixation associated with vascular plants was more important in humid areas. Nitrogen fixation associated with trees and shrubs was almost absent in arid areas, even though Mimosoideae species dominate. Soil NO emissions increased with temperature and moisture and were therefore estimated to be lower in drier areas. The isotopic pattern observed in the Kalahari (15N enrichment with aridity) agrees with the lower soil organic matter, soil C/N, and N2 fixation found in arid areas. However, the estimated NO emissions would cause an opposite pattern in d15N, suggesting that other processes, such as internal recycling and ammonia volatilization, may also affect isotopic signatures. This study indicates that spatial, and mainly temporal, variability of precipitation play a key role on N cycling and isotopic signatures in the soil–plant system. URI: http://hdl.handle.net/10311/577 Files in this item: 1
ARANIBAR2004NITROGEN CYCLING.pdf (2.135Mb) -
Kamwendo, G. H. (Nordic Association of African Studies. http://www.njas.helsinki.fi, NaN, 2006)[more][less]
Abstract: In 1994, South Africans of all races and political parties took part in the first democratic elections. The election and inauguration of Nelson Mandela as the first black president marked the beginning of a new era - an era of democracy. The new era has, among other things, witnessed reforms in language planning. The current paper is a critique of South Africa's language planning efforts during the first decade of democracy i.e. 1994-2004. URI: http://hdl.handle.net/10311/1097 Files in this item: 1
kamwendo_NJAS_2006.pdf (108.8Kb) -
Akpabio, E.; Mustapha-Lambe, K. (Brill academic publishers, NaN, 2008)[more][less]
Abstract: From the viewpoint of the cultural imperialism hypothesis and its complications, the overall aim of this study was to find out if foreign films still had a stranglehold on Nigerian audience members. The findings indicate that a majority of respondents watch and have a favorable attitude towards Nigerian home video films. However, in terms of preference between local and foreign films, a small percentage indicated preference for the former. The study concludes that the high squality of production of American films accounts for the favorable views held by respondents, even though it is apparent that these and other foreign productions no longer have a captive market in Nigeria. URI: http://hdl.handle.net/10311/463 Files in this item: 1
Akpabio_pgdt_2008.pdf (1.184Mb) -
Abegaz, B.M.; Ngadjui, B.T.; Bezabih, M.; Mdee, L.K. (International Union of Pure and Applied Chemistry. http://www.iupac.org/publications/pac/, NaN, 1999)[more][less]
Abstract: Marketed plants are an important but a vulnerable group of plants whose investigations as well as conservation should be considered with priority. The chemistry, and in some cases biological activities of novel iso¯avonoids, nor-lignans, anthracene and naphthalene derivatives and poly prenylated ¯avonoids isolated and characterized from Hagenia abyssinica, Salsola somalensis, Hypoxis spp., Taverniera abyssinica, Aloe spp., Bulbine capitata, Rhamnus prinoides and Dorstenia spp. are discussed. URI: http://hdl.handle.net/10311/289 Files in this item: 1
Novel natural products.pdf (4.533Mb) -
Nedović-Budić, Z.; Knaap, G.; Budhathoki, R.N.; Cavrić, B. (Urban and Regional Information Systems Association, http://www.urisa.org/, NaN, 2009)[more][less]
Abstract: This paper presents an assessment of the regional capacity in implementing geographic information systems (GIS) and databases. We draw on a Web survey to determine the availability and assembly of spatial data at the metropolitan level in the United States. Information was sought from 388 planning organizations and regional agencies located in 349 metropolitan areas. Based on 116 responses (30 percent response rate), we generate descriptive statistics and run a regression model addressing the following aspects of the regional GIS capacity: data (contents, update, and assembly); technology (compatibility of software and data formats, data access, and the use of standards); people (staff, leadership commitment and support, regional communication and cooperation); policy (data sharing, funding, rules and responsibilities, and mandates/programs); and context (urban and regional issues and affluence). Although the survey reveals only a snapshot of a dynamic and evolving phenomenon, the results indicate that the status of metropolitan GIS in the United States may not be matching what is technically feasible. While the capacity is getting better over time, the process is relatively slow and the challenges of creating the base for building the National Spatial Data Infrastructure (NSDI) are persistent. Future research and practice should place more emphasis on the relationship between the NSDI and its installed base. Nurturing of networks and compatibilities among organizational entities at various levels, local and regional in particular, should be given priority in devising policies and programs for a useful and sustainable spatial data infrastructure. URI: http://hdl.handle.net/10311/1022 Files in this item: 1
cavric2009BUILDINGBLOCKS.pdf (2.681Mb) -
Kaelo, P.; Ali, M.M. (Elsevier; www.elsevier.com/locate/ejor, NaN, 2006)[more][less]
Abstract: Modifications in mutation and localization in acceptance rule are suggested to the differential evolution algorithm for global optimization. Numerical experiments indicate that the resulting algorithms are considerably better than the original differential evolution algorithm. Therefore, they offer a reasonable alternative to many currently available stochastic algorithms, especially for problems requiring 'direct search type' methods. Numerical study is carried out using a set of 50 test problems many of which are inspired by practical applications. URI: http://hdl.handle.net/10311/64 Files in this item: 2
kaelo_EJOP_2006.pdf (1.708Mb)license.txt (1.998Kb)