Browsing Department of Mathematics and Computer Sciences by Issue Date
Now showing items 1-20 of 23
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Uniaxial stress dependence of the binding energy of shallow donor impurities in GaAs–(Ga,Al)As quantum dots
(IEEE Xplore, 2001-07)We have studied the effects of an uniaxial stress on the binding energy of a shallow donor impurity in a parallelepiped-shaped GaAs–(Ga,Al)As quantum dot. In the calculations we have used a variational technique within the ... -
The Effect of Uniaxial Stress on the Density of States of Shallow Donor Impurities in GaAs Quantum Wells
(IOP, 2002)We have calculated the density of impurity states (DOIS) as a function of applied uniaxial stress of shallow hydrogen donor impurity in a quantum well (QW). The calculations were carried out using a variational procedure ... -
Elimination of superimposed Multipath effects on Scintillations index on solar quiet ionosphere at Low Latitude over the Kenyan Airspace from a lone Positioned SCINDA system
(Proceedings of the 23rd International Technical Meeting of The Satellite Division of the Institute of Navigation (ION GNSS 2010), Portland, 2010-09)ABSTRACT In communication involving links between satellites and ground stations the most serious effects on transionospheric radio signals is scintillation. By using satellite Navigation Systems such as Global ... -
Total electron content of the ionosphere at two stations in EastAfrica during the 24–25October 2011 geomagnetic storm
(ELSELVIER, 2011-10-25)The equatorial ionosphere has been known to become highly disturbed and thus rendering space-based navigation unreliable during space weather events, such as geomagnetic storms. Modern navigation systems, such as the Global ... -
Charge Transport and Electrical Switching in Composite Biopolymers
(CC BY 3.0 license, 2011-11-14)Polymers are long chain macromolecules made up of many repeating units called monomers. They are found in nature and can also be made synthetically. Natural/bio polymers are considered to be environmental benign materials ... -
Comparison of GPS TEC variations with IRI-2007 TEC prediction at equatorial latitudes during a low solar activity (2009–2011) phase over the Kenyan region
(ELSELVIER, 2012)This work presents an analysis of the Total Electron Content (TEC) derived from the International GNSS Service (IGS) receivers at Malindi (mal2: 2.9oS, 40.1oE, dip −26.813o), Kasarani (rcmn: 36.89oE, 1.2oS, dip −23.970o), ... -
Using GPS-SCINDA observations to study the correlation between scintillation, total electron content enhancement and depletions over the Kenyan region
(CiteULike, 2012-02)This paper presents the first results of total electron content (TEC) depletions and enhancement associated with ionospheric irregularities in the low latitude region over Kenya. At the low latitude ionosphere the diurnal ... -
Comparison of GPSTECmeasurements with IRI-2007TEC prediction over the Kenyanregion during the descendingphase of solarcycle23
(ELSELVIER, 2012-03-01)This paper presents an analysis of the Total Electron Content (TEC) derived from the International GNSS Service receiver (formerly IGS) at Malindi (2.9°S, 40.1°E), Kenya for the periods 2004–2006 during the declining phase ... -
Characterization of ionospheric GPS Total Electron Content (GPS–TEC) in low latitude zone over the Kenyan region during a very low solar activity phase
(ELSELVIER, 2012-08)The ionosphere Total Electron Content (TEC), derived by analyzing dual frequency signals from the Global Positioning System (GPS) recorded from two stations in the Kenyan region is studied. We present the mean diurnal, ... -
Characterization of ionospheric GPS Total Electron Content (GPS–TEC) in low latitude zone over the Kenyan region during a very low solar activity phase
(Elsevier, 2012-08)The ionosphere Total Electron Content (TEC), derived by analyzing dual frequency signals from the Global Positioning System (GPS) recorded from two stations in the Kenyan region is studied. We present the mean diurnal, ... -
Solar activity dependence of total electron content derived from GPS observations over Mbarara
(ELSELVIER, 2012-08-15)Vertical total electroncontent (VTEC) observed at Mbarara (geographic co-ordinates: 0.60°S, 30.74°E; geomagnetic coordinates: 10.22°S, 102.36°E), Uganda, for the period 2001–2009 have been used to study the diurnal, seasonal ... -
Total electron content of the ionosphere at two stations in East Africa during the 24–25 October 2011 geomagnetic storm
(ELSELVIER, 2012-10)The equatorial ionosphere has been known to become highly disturbed and thus rendering space-based navigation unreliable during space weather events, such as geomagnetic storms. Modern navigation systems, such as the Global ... -
On the Steady MHD Poiseuille Flow between Two Infinite Parallel Porous Plates in an Inclined Magnetic Field
(American Journal of Computational and Applied Mathematics, 2013)In this paper, we examine the motion of a two dimensional steady flow of a viscous, electrically conducting, incompressible fluid flowing between two infinite parallel plates one of which is porous and under the influence ... -
Activation of Spent Bleaching Earth for Dehumidification Application
(wajbasarhives.webs.com, 2013-10)To circumvent the current pollution-prone disposal of the spent bleaching earth (SBE), an experimental program was conducted to recover the waste SBE and to use it for air dehumidification application. Waste SBE was obtained ... -
Comparison of GPS TEC variations with IRI-2007 TEC prediction at equatorial latitudes during a low solar activity (2009–2011) phase over the Kenyan region
(Elsevier, 2013-11-15)This work presents an analysis of the Total Electron Content (TEC) derived from the International GNSS Service (IGS) receivers at Malindi (mal2: 2.9oS, 40.1oE, dip −26.813o), Kasarani (rcmn: 36.89oE, 1.2oS, dip −23.970o), ... -
Dust-acoustic supersolitons in a three-species dusty plasma with kappa distributions
(Cambridge University Press, 2013-12) -
Assessment of existing improved cook stoves in Kenya
(www.injctr.com, 2014)This study made to explore the use of ICS in different parts of Kenya- to identify the types of ICS used; determine cooking practices of the people; ascertain the impact of the ICS on the peoples socio-economic ... -
Anisotropic Photophysical Properties of Highly Aligned Crystalline Structures of a Bulky Substituted Poly(thiophene)
(American Chemical Society, 2014)ABSTRACT: The photophysical properties of a phenylsubstituted poly(thiophene), poly(3-(2,5-dioctylphenyl)- thiophene) (PDOPT), were studied as a function of polarization and degree of orientation of the crystalline structure. ... -
The determinant of the relationship between the knowledge on HIV/AIDs and safety measures taken MSEsGikomba market,(Nairobi,Kenya
(http://scholarpublishing.org, 2014)Kenya is among the world’s nations affected by HIV/AIDS with the virus claiming 600 people per day. The most endangered are the young people of the age bracket of 15-49 years who own/managers and employees of the Micro ... -
Models and experiments for energy consumption and quality of green tea drying
(the Society of Chemical Industry and John Wiley & Sons Ltd., 2015)An experimental apparatus has been developed to evaluate the drying process of green tea leaves. Tea drying is an energy-intensive process which results in the removal of leaf moisture; it is essential to the quality of ...