Numerical Solution of SIR Model using Differential Transformation Method and Variational Iteration Method

Abstrac

Development and testing of a graphical FORTRAN learning tool for novice programmers

To address the difficulties associated with computer programming, this article first looks at some reasons why students, especially engineering students, find programming such a daunting prospect, and it proposes a programming learning tool managed by a Deterministic Finite Automaton (DFA). The DFA machine used a graphical environment provided by Simulink to teach the FOR-mula TRANslator (FORTRAN) programming language to science students. The proposed programming learning tool and the traditional method of teaching were compared and evaluated. The results of evaluation indicated that there was an improvement in learning effectiveness of the proposed learning tool

MEASUREMENT OF RADIATION DOSE IN SELECTED CEMENT STORES IN ABEOKUTA, OGUN STATE, USING GM SURVEY METER

Measurements were carried out using a Geiger Muller Survey Meter and a Global Positioning System (GPS) to find  the outdoor absorbed dose rates in selected cement stores in Abeokuta, Ogun State, Nigeria. The outdoor  absorbed dose rates  (control sites 10m away from cement depot) ranged from 400 nGy/hr) (Sapon) to 740 nGy/hr (Adatan) with the mean 554.7 ± 0.08 nGy/hr  and the indoor absorbed dose rate (store) ranged from 740 nGy/hr  (Lafenwa1&2) to 1240 nGy/hr (Isale-Ake) with the mean 909.3 ± 16 nGy/hr. The corresponding annual effective dose rates for the control sites ranged from 1.13 mSv/yr (sapon) to 2.09 mSv/yr (Adatan) with the mean 1.57 ± 0.32  mSv/yr, while it ranged from 2.45 mSv/yr (Lafenwa1&2) to 4.11 mSv/yr (Isale ake) for the cement depots  with the mean 3.01 ± 0.52 mSv/yr. It has been revealed from this study that cement may enhance exposure to radiation, since the value of the absorbed dose rates in the stores are higher than thoseof the control sites. The values for the annual effective dose calculated are higher than 1mSv/yr. &nbsp

ABSORBED DOSE RATES ABOVE SOILS AND ROCK OUTCROPS IN SELECTED AREAS OF ABEOKUTA, NIGERIA

Outdoor absorbed dose rates were measured in selected areas of Abeokuta in Nigeria; some with rock outcrops and others with soil overburden. Measurements were carried out using a Geiger Muller Survey Meter and a Global Positioning System (GPS). Result shows absorbed dose rates ranged from 1.0 x 103 to 1.3 x 103 nGy/hr among the rock outcrop areas and from 0.6 x 103 to 0.8 x 103 nGy/hr among the soil -covered areas. The average absorbed dose rate was 1180 ±3 nGy/hr for the rock outcrop areas and 689 ±3 nGy/hr for the soil -covered areas and assuming 0.4 occupancy factor, the corresponding average annual effective dose rates were calculated to be 2.89 ± 0.01 mSv/yr for the rock outcrop areas and 1.69 ± 0.01 mSv/yr for the soil –covered areas based on occupancy factor of 0.4. The mean annual effective dose rates for both the rock outcrop and soil covered areas were  found to be higher than 1mSv/yr, the recommended dose limit for the public.     &nbsp

IMPLEMENTATION OF THE ROOT BISECTION COMPUTATIONAL PHYSICS METHOD FOR THE DETERMINATION OF ROOTS OF NON-LINEAR EQUATIONS USING JAVA

Advancement in programming and language development has made possible improved efficiency and accuracy in solving numerical problems and hence the numerical computation of physical problems as used in Computational Physics. Hitherto, languages such as Basic, Fortran, C, among others, have commonly been employed in solving numerical problems. In this work, Java, a modern object oriented language was deployed in solving some physical problems, specifically, determination of roots of non-linear equations using the Root-Bisection Method. A comparison between results obtained showed faster convergence and greater accuracy using Java than as obtained using Fortran.     &nbsp

GEOELECTRIC PARAMETERS AND ELEMENTAL COMPOSITIONS OF THE TOP SOIL OF CAMP AREA, ABEOKUTA, SOUTH WESTERN NIGERIA

Vertical Electrical Sounding (VES) and elemental composition surveys were carried out at twenty-two (22) sites atª¤? Camp Area, Alabata Road, Abeokuta, Southwestern Nigeria. This was with a view to determining depth to water«¤??bearing zones and extent of soil contamination thereby saving residents not just the pain of recurrent losses incurred for investing in dry wells, but also not to invest in contaminated waters. The study area is underlain by associated rock suites which includes pegmatite and quartz veins. Field data obtained was modeled and interpreted to obtain the geophysical parameters of the area and delineate the groundwater potential zones. Soil samples were also collected at the 22 VES points, at depths of 10 cm and 100 cm; the Global Positioning Satellite (GPS) equipment was used to obtain the geographical position of each sample point. Determination of the elemental composition of soil samples collected at the 10 cm and 100 cm depths was made using Atomic Absorption Spectrophotometer. Two heavy metals (Pb, and Cr), five major elements (K, Ca, N, P and Mg) and five trace elements (Zn, Mn, Cu, Al and Fe) were detected. It was observed that the values, representing the amount of the heavy metals, the major elements, and the trace elements were far less, mostly insignificant, at the 100 cm depth representing about the interface between the first and second layers in majority of the VES stations sampled, than at the 10 cm depth, representing the topsoil of the first layer. The implication of this is that the elements are not strictly domiciled within the area studied but may be due to runoffs as the area slopes down. Moreover, going by the values at the 100 cm depth, the elements may not be capable of percolating into the underground water zones in the area of study, and thus might not have contaminated the underground water. Thus, at the current level, the underground water can be adjudged safe for human consumption.ª¤

COMPARISON OF ACTIVITY CONCENTRATIONS OF NATURAL RADIONUCLIDES IN SOILS COLLECTED AT DIFFERENT DEPTHS OF SELECTED HAND-DUG WELLS IN ABEOKUTA

This study was aimed at measuring and comparing the activity concentration of soil samples collected from some selected hand – dug wells with their corresponding depths of collection in Abeokuta metropolis. Total of twenty (20) soil samples were collected from hand-dug wells in five sites (Obada, Adigbe, Kuto, Olorunsogo, and Obantoko) within Abeokuta with four (4) soil samples from each hand-dug well at the surface, (0.0m) through to 2.25m depth. Gamma ray spectroscopy with High Purity Germanium (HPGe) detector was used for the measurements. The average activity concentrations obtained for the three natural radionuclides 226Ra, 232Th and 40K in Bq/Kg are 34.31 ± 2.01, 128.73 ± 4.41 and 152.31 ± 2.59 respectively at depth 0.00 m (surface), 23.00 ± 1.61, 68.39 ± 3.24 and 191.08 ± 3.11 respectively at depth 0.75 m, 31.52 ± 2.21, 145.37± 4.95 and 375.56 ± 5.50 respectively at 1.50 m and lastly 28.57±1.70, 95.61 ± 3.71 and 181.10 ± 3.94 respectively at 2.25 m depth. The world average activity concentrations for 226Ra, 232Th and 40K are given to be 35 Bqkg-1, 30 Bqkg-1 and 400 Bqkg-1 respectively (UNSCEAR 2000). 232Th showed  higher average values than the world’s average while averages of 226Ra and 40K were lower but most of the activity concentration values obtained in some of the locations are higher than the world’s average values, especially 226Raand 232Th in the soil samples.

Investigation and Comparison of Heat Generated by Coloured Metallic Plates in Response to the Emissive and Absobtion Power of the Surfaces of the Coloured Plate

A colour test was carried out to determine the rates of absorption and emission of infrared radiation by coloured hollowed metallic plates which result in increase in temprature of the holllowed plates at maximum radiation of 750 Wm-2 at Abeokuta 7.198305 and Longitude 3.439533 during the month of March 2013. Five hollow metallic plates of different paint colours (black, green, red, blue and white) were exposed to sunlight simultaneously and the temperature generated in each plate was recorded using a data logger. A wooden box that was divided into five cavities was constructed and lagged with wood shavings to provide insulation and the five coloured hollowed metallic plates of dimension d=4h were inserted in it. The choice dimension d=4h is to minimise shading of the inside of the plate (d is the diameter of each of the plates and h is the height) the top of the plates were covered with a 5 mm thick glass. The top cover plates were securely laid tightly to both the wooden box and the tip of the plates to prevent heat loss to the surrounding and also from crossing from one plate to another.  This arraignment is similar to that of a flat plate collector and calorimeter experiment. The centre of each of the plate was connected to five probes of a data logger and the temperature of changes inside the plates are logged and recorded

Optimum Angle of Inclination for a Fixed Stand-Alone Photovoltaic: A Review

The optimum angle of tilt for PV system is very important for best performance in the generation of power and other related use of photovoltaic. This work, reviews the best angle of inclination for a stand-alone photovoltaic panel. The consideration of various studies has been looked at in line with some models. It was observed that the yearly fixed angle of tilt is close to or same as the latitude for a given location, although this may not be appropriate for use in other locations. The annual optimal angle of tilt of some locations were closely related in value i.e. 20.50o, 20.50o, 21.50o, 20.20o, 21.30o and 22.40o. The best electrical performance for the PV system was observed to be above 1598kWh/m2 at20o inclination facing south. Hencethe value of the optimum angle of tilt for best electrical performance of an array of stand-alone PV system could vary between 0o and 90o depending on the location latitude

Relationship between CD4 count and quality of life over time among HIV patients in Uganda: A cohort study

© 2015 Mwesigire et al. Background: Immunological markers (CD4 count) are used in developing countries to decide on initiation of antiretroviral therapy and monitor HIV/AIDS disease progression. HIV is an incurable chronic illness, making quality of life paramount. The direct relationship between quality of life and CD4 count is unclear. The purpose of this study is to determine the relationship between change in CD4 count and quality of life measures in a Ugandan cohort of people living with HIV. Methods: We prospectively assessed quality of life among 1274 HIV patients attending an HIV clinic within a national referral hospital over a period of 6months. Quality of life was measured using an objective measure, the Medical Outcomes Study HIV health survey summarized as Physical Health Score and Mental Health Score and a subjective measure, the Global Person Generated Index. Generalized estimating equations were used to analyze the data. The primary predictor variable was change in CD4 count, and the outcome was quality of life scores. We controlled for sociodemographic characteristics, clinical factors and behavioral factors. Twenty in-depth interviews were conducted to assess patient perception of quality of life and factors influencing quality of life. Results: Of the 1274 patients enrolled 1159 had CD4 count at baseline and six months and 586 (51%) received antiretroviral therapy. There was no association found between change in CD4 count and quality of life scores at univariate and multivariate analysis among the study participants whether on or not on antiretroviral therapy. Participants perceived quality of life as happiness and well-being, influenced by economic status, psychosocial factors, and health status. Conclusions: Clinicians and policy makers cannot rely on change in immunological markers to predict quality of life in this era of initiating antiretroviral therapy among relatively healthy patients. In addition to monitoring immunological markers, socioeconomic and psychosocial factors should be underscored in management of HIV patients