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A numerical study of some modified differential evolution algorithms

Kaelo, P.; Ali, M.M. (Elsevier; www.elsevier.com/locate/ejor, NaN, 2006)

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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)

On semi-parallel lightlike hypersurfaces of indefinite Kenmotsu manifolds

Massamba, F. (Birkhäuser Basel. http://www.springerlink.com/content/107580/?p=1930c3cc1de944feae211b785b3b42a4&pi=0, NaN, 2009)

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Abstract:

We study semi-parallel lightlike hypersurfaces of an indefinite Kenmotsu manifold, tangent to the structure vector field. Some Theorems on parallel and semi-parallel vector field, geodesibility of lightlike hypersurfaces are obtained. The geometrical configuration of such lightlike hypersurfaces is established. We prove that, in totally contact umbilical lightlike hypersurfaces of an indefinite Kenmotsu manifold which has constant φ-holomorphic sectional curvature c, tangent to the structure vector field and such that its distribution is parallel, the parallelism and semi-parallelism notions are equivalent.

URI:

http://hdl.handle.net/10311/539

Files in this item: 1

On semi-parallel.pdf (1.027Mb)

Renewable energy education in Botswana: needs, status and proposed training programs

Jain, P.K.; Lungu, E.M.; Mogotsi, B. (Elsevier Science Ltd. http://www.sciencedirect.com/science/journal/09601481, January NaN, 2002)

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Abstract:

Lack of trained manpower for repair and maintenance of solar energy devices in Botswana has resulted in failure of devices, loss of revenue, and dwindling of consumer faith in solar technologies. The government of Botswana commissioned a study to assess the needs for trained manpower in New and Renewable Sources of Energy (NRSE) technologies, to identify the required training programs and their levels, and the facilities that need to be upgraded and/or created for the implementation of such training programs at the existing technical and educational institutions within the country. The paper presents the findings of the study, and the recommendations made. The study proposed seven training programs at progressively increasing skills and expertise levels that include two certificate courses in each of the solar water heating and photovoltaic technologies for maintenance personnel, a national craft certificate program in solar energy technologies, a higher diploma in energy technologies for supervisory personnel, and a short course for upper management personnel in decision-making positions in order to raise their skills in the procurement of equipment and services, and to provide overall effective leadership. A short course to upgrade the skills of the present maintenance personnel to alleviate the immediate problems is also proposed. Required upgrading of existing technical training facilities, the creation of new facilities and estimated budgetary requirements constitute some of the recommendations. The recommendations have gone through various channels of discussions, and have been accepted in principle. The report is currently under consideration for implementation by relevant government departments.

URI:

http://hdl.handle.net/10311/137

Files in this item: 2

license.txt (1.998Kb)

Renewable energ ... osed training programs.pdf (1.461Mb)

Screen integrable lightlike hypersurfacesof indefinite sasakian manifolds

Massamba, F. (Birkhäuser Basel. http://www.springerlink.com/content/110963/?p=c42ba01ff0bd482b81a3ebdf3b649c9a&pi=0, NaN, 2009)

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Abstract:	We investigate lightlike hypersurfaces of indefinite Sasakian manifolds, tangent to the structure vector field and whose screen distribution is integrable. We prove some results on parallel vector fields and on a leaf of the integrable distribution D0? h i of this class. A theorem on a geometrical configuration of the screen distribution is obtained. We show that any totally contact umbilical leaf of a screen integrable distribution of a lightlike hypersurface is an extrinsic sphere.
Description:	The mathematical symbols may not come as they are in the abstract.
URI:	http://hdl.handle.net/10311/689

Files in this item: 1

Screen Integrable Lightlike.pdf (1.251Mb)

Stochastic models for sunshine duration and solar irradiation

Jain, P.K.; Lungu, E.M. (Elsevier Science Ltd: http://www.elsevier.com/wps/find/journaldescription.cws_home/969/description#description, NaN, 2002)

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Abstract:

Abstract Harmonic analysis of sunshine duration and solar irradiation measured at Sebele, Botswana is carried out. The data used consists of the monthly averages and the Julian-days averages of sunshine duration and solar irradiation sequences. This study involves splitting the time series into deterministic and stochastic components, and determining the proportion of the variance explained by each component. The stochastic component is analyzed for persistence using the Box and Jenkins technique. It is found that the stochastic component for monthly averages solar radiation series is best described by the second-order autoregressive Markov process, while that for Julian-days averages series has no memory.

URI:

http://hdl.handle.net/10311/138

Files in this item: 2

license.txt (1.998Kb)

Stocastic model ... and solar irradiation.pdf (614.0Kb)

String Homology of a Product of Spheres and the Witt Algebra

Gatsinzi, J-B.; Kwashira, R. (Nova Science Publishers, Inc.; www.novapublishers.com; reprinted with permission from Nova Science Publishers, Inc., NaN, 2007)

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Abstract:	Let X be a finite product of even dimensional spheres, we show that the string homology of X contains a finite product of copies of the Witt Lie algebra.
URI:	http://hdl.handle.net/10311/162

Files in this item: 1

gatsinzi-kwashira1.pdf (139.6Kb)

A study of pulsatile blood flow modeled as a power low fluid in a constricted tube

Prakash, J.; Ogulu, A. (Elsevier; www.elsevier.com/locate/ichmt, July NaN, 2007)

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Abstract:	A mathematical model for the pulsatile blood flow in a small vessel in a cardiovascular system with a mild stenosis is analyzed. Blood is modeled as a power low fluid and the differential approximation for the heat flux is invoked in the energy equation. The effect of heat transfer on the velocity is computed and discussed.
URI:	http://hdl.handle.net/10311/226

Files in this item: 2

license.txt (1.998Kb)

Prakash_ICHMT_2007.pdf (772.9Kb)

Teachers’ experiences with an adapted IGCSE physics syllabus in Botswana

Koosimile, A.T. (Elsevier, www.elsevier.com/locate/ijedudev, NaN, 2005)

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Abstract:

This paper focuses on teachers’ experiences with implementing a modified International General Certificate of Secondary Education (IGCSE) physics syllabus in Botswana. The syllabus, characterised by a new organisational and pedagogic paradigm, is a significant shift from the traditional ‘‘teacher-proof’’ syllabus to one that is flexible, nonprescriptive and student-centred. Through data from discussions and interviews with teachers, it emerged that policy statements on the nature of the syllabus were contradictory and confusing to guide both the adoption and implementation of the syllabus. It also emerged that teachers accorded the core curriculum component of the syllabus a lower priority and status than the extended curriculum component. The findings also reveal that considerable overlaps in the core and extended curriculum components of the syllabus blurred the distinction between the two as well as weakening prospect of fidelity of adoption and implementation. The resulting ‘innovation gap’ invariably means that the ideals of the syllabus and the associated paradigm shifts are possibly not realised in teaching in Botswana. The findings generally underscore the importance of clear guidance and policy statements on any new syllabus, and indeed, a new curriculum. Possible directions in future research would be to investigate innovation gaps that might be manifest in teaching.

URI:

http://hdl.handle.net/10311/499

Files in this item: 1

Koosimile2005ICGSEphysics.pdf (1.142Mb)

Thermal analysis and annealing temperature dependence of electrical properties in Sn10Sb20Se70 glassy semiconductor

Kumar, P.; Thangaraj, R.; Sathiaraj, T.S. (Springer Netherlands, NaN, 2008)

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Abstract:	The melt-quenched Sn10Sb20Se70 sample in the bulk form was used to prepare films on well-cleaned glass substrates by thermal evaporation method. The activation energy for glass transition (apparent) and crystallization has been analyzed by using the Kissinger formulation. The X-ray diffraction study shows the crystallization of Sb2Se3 phase in the major proportion as compared to the SnSe2 phase. The SEM images film of the show the appearance of spherical globules upon annealing below the glass transition temperature. The effect of annealing temperature on the electrical and optical properties has been studied. A linear fit between DE and Eo is observed, indicating the validity of Meyer–Neldel rule with the change in the annealing temperature.
Description:	some mathematical symbols may not come as they are in the title and abstract.
URI:	http://hdl.handle.net/10311/691

Files in this item: 1

Thermal analysis.pdf (949.2Kb)

Vector measures of bounded semivariation and associated convolution operators

Saab, P.; Robdera, M.A. (Glasgow Mathematical Journal Trust, http://journals.cambridge.org/action/displayJournal?jid=GMJ, NaN, 2011)

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Abstract:	Let G be a compact metrizable abelian group, and let X be a Banach space. We characterize convolution operators associated with a regular Borel X-valued measure of bounded semivariation that are compact (resp; weakly compact) from L1(G), the space of integrable functions on G into L1(G)ˇ⊗X, the injective tensor product of L1(G) and X. Along the way we prove a Fourier Convergence theorem for vector measures of relatively compact range that are absolutely continuous with respect to the Haar measure.
Description:	the symbols on the abstract may differ from the original script
URI:	http://hdl.handle.net/10311/1004

Files in this item: 1

Saab_GMJ_2012.pdf (83.98Kb)

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