Physics Research Papers/Topics

Move-Biased Monte Carlo Simulation Method for Protein Native Structure Prediction

ABSTRACT Proteins are polymers of Amino Acid (AA) which are constructed after translation of genetic code in DNA of organisms, and have functionality that depends on their Native Structure (NS). Experimental methods for protein NS determination are complicated, expensive and timeconsuming. Consequently, Computational Methods (CM), including Monte Carlo (MC), aim to circumvent these challenges. However, the MC is complex and inconsistent in NS Prediction (NSP). This study was designed to deve...

INVESTIGATING THE DYNAMICS AND DRIVERS OF EXTREME RAINFALL IN GHANA

ABSTRACT Daily rainfall data from Ghana Meteorological Agency (GMet) rain gauge network was analysed to identify extreme rainfall events in Ghana. The data was first processed in order to remove all errors in the observational time series prior to analysis. The data was then analysed by excluding all rainfall events, which fell below a pre-determined threshold in order to identify extreme rainfall event days and non-extreme event days. Inter-annual variability and trends of annual precipitati...

QUANTUM DOT SOLAR CELLS

ABSTRACT In this thesis, hot carrier relaxation dynamics in semiconductor quantum dots and quantum well structures have been investigated as the basis for improving on the efficiency of conventional solar cells to values between 40% and 60% beyond the Shockley and Queisser detailed balance limit of 30% hitherto. Two schemes have been employed to obtain the shift in efficiency: The first is multiple exciton generation which occurs in semiconductor quantum dots. The output current as a function...

Spectroscopic Studies of Some Selected Anti-Malarial Herbal Plants Sample Combined With Multivariate Data Analysis

ABSTRACT Two spectroscopic techniques: Laser-Induced Fluorescence (LIF) and Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) spectroscopy and soil analysis were used to study and classify Anti-Malarial Herbal plants (AMHPs) from four locations (Abrafo, Jukwa, Nfuom and Akotokyere) in the Cape Coast metropolis. Deconvoluted peaks from the LIF spectra of the AMHPs samples showed compounds such as berberine, quercetin, flavanols presents in all the AMHPs samples. Principal com...

VALIDATION OF PLANNED RADIATION ABSORBED DOSE FOR BREAST CANCER TREATMENT USING RADIOMETRIC FILM DOSIMETER

ABSTRACT The essential role of radiotherapy is to ensure detection and treatment of breast cancers using appropriate doses, these seem not to harm patients under review. Unintended detriments in the treatment and the risk of secondary cancers are mostly associated with delivering much higher doses than planned dose. This study focused on using phantoms for the determination, and comparison of planned doses with actual doses delivered to the breast, during radiation treatment. Adelaide phantom...

WAVELENGTH MODULATION ABSORPTION SPECTROSCOPY WITH 2f SIGNAL DETECTION: APPLICATION TO MOLECULAR OXYGEN DETECTION

ABSTRACT Wavelength modulation spectroscopy using second harmonic (2f) signals is one of the modulation techniques in absorption spectroscopy used to improve the absorption signal by noise reduction. This second harmonic (2f) signal has been simulated using MATLAB, a new approach based on numerical integration, to investigate the influence of normalized modulation amplitude, m and the optimal 2f signal was found to occur at m = 2.1. Experimentally, free molecular oxygen gas was measured at th...

DEVELOPMENT OF DOAS REMOTE SENSING SYSTEM FOR GROUND-BASED MEASUREMENTS OF TRACE GAS EMISSIONS IN AN INDUSTRIAL AREA

ABSTRACT A DOAS system has been developed and deployed to determine horizontal concentrations of such pollutants as NO2, SO2 and O3 in Bologna, Italy and Tema, Ghana. Measurements were conducted in Italy during the winter season of March 2005 and in Ghana during the dry harmattan season in January 2008 and raining seasons in July and August 2008. Their average lineof-sight concentrations were determined by measuring the scattered solar radiation through three optical windows in the zenith and...

A FIBRE OPTICAL SYSTEM FOR REFLECTANCE MEASUREMENT OF PLANE SURFACES

ABSTRACT A simple fibre optical design for reflectance measurements of plane surfaces has been developed and tested. The reflectance system was standardized with a PF10-03-P01-Plane mirror. Average reflectance from the plane mirror was 99.7%, 99.5% and 70.0% for the 1310 nm, 850 nm LED sources and 632.8 nm He-Ne laser respectively. Average reflectance decreased with decreasing wavelength. Steel and aluminium metal plates showed different trends in average reflectance values. The microscope sl...

MEASUREMENT OF ABSORBED DOSE TO ORGANS AT RISK IN HIGH DOSE RATE BRACHYTHERAPY OF THE CERVIX

ABSTRACT Radiation dose to bladder and rectum in the treatment of cervical cancer using high dose rate brachytherapy is a limiting factor to the delivery of the prescribed dose to the target. The objective of this study is to determine absorbed dose to the bladder and rectum (organs at risk) in the treatment of cervical cancer using multisource high dose rate brachytherapy treatment system in order to establish an in-vivo dosimetric and quality assurance protocol for patient treatment. A phan...

DYNAMIC ANALYSIS OF THE WEST AFRICAN MONSOON AND ITS VARIABILITY OVER GHANA

ABSTRACT In this study, the International Center for Theoretical Physics’ Region l Climate Model Version 4 (RegCM4) is used over the period 1998-2010, to study the dynamics of rainfall over West Africa. The study also attempts to understand the West African Monsoon (WAM) circulation and its characteristics. Global Precipitation Climatology Project precipitation (GPCP), Tropical Rainfa ll Measuring Mission (TRMM), global atmospheric reanalysis (ERA-Interim, ERAINT), RegCM4 winds and National...

ESTIMATION OF GLOBAL SOLAR RADIATION IN SELECTED SYNOPTIC STATIONS IN GHANA

ABSTRACT The global solar radiation potential of eight Synoptic Meteorological Stations in Ghana was reported in this study. Five stations were selected from the Northern belt, mostly made up of Sudan Savanna and Guinea Savanna regions of Ghana and the other three stations were selected from the Middle belt, mainly Deciduous Forest and Coastal Savanna regions of Ghana. AngstromPrescott Sunshine Hour Model was employed to estimate the global solar radiation for these stations. The daily sunshi...

ENERGY-ECONOMIC ANALYSIS OF POWER PLANT CARBON DIOXIDE CAPTURE AND PIPELINE TRANSPORT IN TEXAS GULF COAST

ABSTRACT  The total investment cost of a pipeline network to transport carbon dioxide (CO2) from power plants for enhanced-oil-recovery (EOR) in oil fields in Texas Gulf Coast as CO2 mitigation has been estimated. The impact of the CO2capture and transport on power generation cost, including the benefits of atmospheric CO2mitigation has also been determined. 14 power plants comprising 55.7% of installed capacity in Texas Gulf Coast were selected. Geographical-information system was used ...

Comparison Of Three Numerical Methods For Estimating Weibull Parameters Using Weibull Distribution Model In Nigeria

There is a crucial need in Nigeria to enhance the development of wind technology in order to boost our energy supply. Adequate knowledge about the wind speed distribution becomes very essential in the establishment of Wind Energy Conversion Systems (WECS). Weibull Probability Density Function (PDF) with two parameters is widely accepted and is commonly used for modelling, characterizing and predicting wind resource and wind power, as well as assessing optimum performance of WECS. Therefore, i...

CONSTRUCTION OF SOLAR CELL

Abstract: A solar cell or photovoltaic is a device  which directly converts photon or solar light or sunlight into electricity. Radiation (Light shining) on the solar cell produces both a current and a voltage which create  electric power in most solar panel. This process requires a Material Medium in which the absorption of photon raises an electron to a higher energy state, and the motion of this excited energy electron from the solar cell into an external circuit. The electron then dissi...


211 - 224 Of 224 Results