Abstract During the last decades, cities in sub-saharan Africa have undergone rapid urban growth due to increased population growth and high economic activities. This research explores the impacts of varying modelling settings including spatial extend and its location for the city of Nairobi using a cellular automata (CA) urban growth model (UGM). Our UGM used multi-temporal satellite-based data for classification of urban land-use of 1986, 2000 and 2010, road data, slope data and exclusion ...
Abstract. The mechanism behind the formation of alloyed ohmic contacts to p-type InP doped in the 1016 cm-3 range has been investigated. Techniques used for - characterising the contacts include the scanning electron microscope (SEM), specific contact resistance measurements, x-ray diffractometry (XRD), energy dispersive x-ray analysis (EDAX) and Auger electron spectroscopy (AES). Both temperature and time of annealing were varied during the study. The results obtained using our annealing pr...
ABSTRACT Schistose rocks from Okene-Lokoja area, SW Nigeria, consist of quartz-biotite schist, quartz muscovite schist, amphibole schist, and quartz schist. Major element compositions (oxide wt. %) of the schists together with their trace element contents (Ba. Ce. Cr. La. Li, Ni, Rb, Sr, V, Y, Zn, and Zr) are presented. The schists (excluding the quartzitic variety) are enriched in SiO,,K,O, Rb and Ba but depleted in total Fe, O. Mno. TiO,, MgO, Ni and Zn compared with rocks of similar compos...
Abstract The major lithostratigraphic units of the eastern Dahomey Basin are the Araromi, Ewekoro and Akinbo Formations. Field studies show that the Araromi and Akinbo Formations contain shaly facies, while the Ewekoro Formation contains essentially fossiliferous limestones. The Araromi shales are dark and bituminous, while those of the Akinbo are fissile and concretionary. Selected subsurface and outcrop samples of these lithotypes were analysed to ascertain their palaeodepositional environm...
Sleep specialists often conduct manual sleep stage scoring by visually inspecting the patient’s neurophysiological signals collected at sleep labs. This is, generally, a difficult, tedious and time-consuming task. The limitations of manual sleep stage scoring have escalated the demand for developing Automatic Sleep Stage Classification (ASSC) systems. Sleep stage classification refers to identifying the various stages of sleep and is a critical step in an effort to assist physicians in t...
ABSTRACT Three banana varieties (Omini Red, Cavendish and Cooking banana) were transversely cut into 10 mm slices, pretreated in sucrose solution of 52, 60 and 68°B and maintained at 25°C for 12 hours. Both fresh and pre-osmosed banana slices were subsequently oven-dried at 60°C for 72 hours. Adsorption isotherms of fresh and preosmosed oven-dried banana slices were determined at 20 and 40°C using gravimetric–static method. Suitability of eight sorption models in describing the adsorpt...
Abstract Clay bodies occur as lenses and interbeds within the predominantly shaley Akinbo Formation in the eastern Dahomey Basin. They are greenish to grayish, plastic, and in some places contain concretions. In order to assess their sedimentological significance as well as evaluate their potential as industrial raw materials, representative outcrop arid borehole samples .were subjected to mineralogical, chemical and physical characterisation. • • •, •, > l j . Mineralogical determin...
ABSTRACT The NaI(TI) gamma-ray spectrometer was employed to determine the concentration of the naturally occurring Potassium(K-40). Uranium(U-238) and Thorium(Th-232) vis-a-vis the radiogenic heat production in soil samples from Idi-Omo farmland area of Akinyele Local Government area of Oyo state. The farmland which is at Latitude 070 30' 26.3" and Longitude 003" 5 7' 2 1.9" covers an area of about 80,000 square meter, and is at an average elevation of 240m above mean sea level (msl). The s...
ABSTRACT The antimicrobial activities of two Nigerian medicinal plant commonly used as chewing sticks Zanthoxylum xanthoxyloides and Pseudocedrela kotschyi antimicrobial activities were investigated against 7clinical strains of Streptococcus mutans, Staphylococcus aureus ATCC 29213, Candida albicans, Candida tropicalis and Candida krusei ATCC 6825. The antibacterial and antifungal activities of the extracts were determined using the agar well diffusion and surface plate method respective...
ABSTRACT Anopheles gambiae, the major Afro-tropical malaria vector is resistant to pyrethroid insecticide and this is threatening the impact of malaria control efforts using insecticides. In this study, the major malaria vector species from stagnant water bodies and their susceptibility status to pyrethroid insecticide was determined in some areas of Lagos state, Nigeria. Anopheles larvae were sampled from three areas of Lagos, namely Akoka, Idiaraba and Okobaba and raised to adulthood in the...
ABSTRACT Aloe vera gel (AVG) extract is commonly used as a home remedy for some diseases, including diabetes mellitus. This study investigates the effects of pure Aloe vera (Aloe babardensis) gel on some biochemical, haematological and histological parameters in diabetic rats. The animals were divided into six groups of six rats each (n=6). Diabetes mellitus was experimentally induced in rats by intraperitoneal administration of a single dose of alloxan monohydrate (170 mg/kg BW.) following ...
Abstract Diurnal variation of vertical total electron content (VTEC) over Lagos, Nigeria (6.52° N, 3.399 E, dip latitude 3.03° S) during low solar activity period (2010) and a comparison with NeQuick-model-derived VTEC, are presented in this paper. VTEC generally increases from 0600 h LT and reaches its maximum value at approximately 1400 to 1700 h LT during all months considered. Our result shows that NeQuick model provide a good prediction during daytime and nighttime at Lagos, although s...
ABSTRACT While most universities in the developed world, by tradition, have research offices to handle research management, structures for the efficient coordination and strong governance of research are nascent within many Sub-Saharan African universities. In this paper we look at the organizational structures, policies and functions of research offices for supporting faculty research as well as their management operations in 5 selected Nigerian universities. The authors interviewed 20 part...
Abstract Data clustering has always been an important aspect of data mining. Extracting clusters from data could be very difficult especially when the features are large and the classes not clearly partitioned, hence the need for high-quality clustering techniques. The major shortcoming of various clustering techniques is that the number of clusters must be stated before the clustering starts. A recent successful work in clustering is the Clustering analysis based on Glowworm Swarm Optimizati...
ABSTRACT Nigeria aspires for qualitative education as well as economic prosperity in the year 2010. It is envisaged that there will be a high level of technological sophistication by the twenty-first century world wide. In order not to be left behind there is need for Nigeria to take steps in ensuring high technological advancement as well as having sustainable economic growth. The important role that mathematics plays in science and technology has ensured its inclusion as a compulsory subje...