ABSTRACT The access to a restricted area within a premise is normally done through a manual system of keys and locks. This has been automated through the use of personal identification number (PIN) or passwords and smartcard technology. However, such systems are faced with a number of limitations such as losing a smartcard, forgetting a PIN, duplication of keys and impersonation. Thus, the use of an authentication system such as biometric verification techniques has become an effective altern...
ABSTRACT Digital processors are built from very large scale integration circuits and the software to design them is only available to the manufacturers themselves. There is a need to design a central processing unit using large, medium and small scale integration circuits which can be used as a teaching aid in computer architecture and design. In this thesis a simulation model of a digital processor is designed using arithmetic logic unit, control unit and registers as building blocks with th...
ABSTRACT There is a rapid increase in demand for energy worldwide and one of the most promising approaches to resolve this crisis is through use of photovoltaic technologies. Dye sensitized solar cells (DSSC) are attractive candidates in this regard. This is because the materials they use are of low cost and non-toxic. Niobium pentoxide (Nb2O5) thin films have been stable as photo anode for DSSC. Methods that are used to deposit niobium pentoxide thin films include hydrothermal method, solgel...
ABSTRACT Thin film semiconductors of SnxSey and aluminum doped ZnO are potential candidates for the development of future generation improved efficiency and low cost solar cell devices. This is due to their high absorption co-efficient and good optical properties in the visible region of the solar spectrum. Optical characterization of the two thin films under varied composition and deposition conditions was done by optimizing them for an improved solar cell. Deposition of both SnxSey and ZnO:...
ABSTRACT Air pollution is a major factor of consideration in the evaluation of quality of life and as an environmental issue in urban areas. Among the urban air pollutants, carbon monoxide (CO) is one of the most prevalent and having serious health as well as environmental effects. The availability of accurate information about its concentrations, variations and location is vital in the determination of urban air pollution. A number of devices for carbon monoxide monitoring have been designed...
ABSTRACT Indium Selenide (InxSey) has shown great advantages over the conventionally used Ge2Sb2Te5 as a phase change memory material (PCM). It has been established that the electrical resistivity of Indium-Selenide based memory cell can be varied by a factor of 105 related with the degree of crystallization as compared with 103 for Ge2Sb2Te5. It is this wider change of electrical resistivity and higher electrical resistivity that has attracted great attention to Indium-Selenide based phase ...
ABSTRACT Thin films for solar cell application have been found to be unstable when used in extreme weather conditions. Therefore there is a quest for the study of effects on light soaking and exposure to outdoor conditions on SnxSey/ZnO:Sn solar cell. A p-n junction thin film solar cell was prepared using SnSe as the absorber layer and ZnO:Sn as a window layer. Tin selenide thin films were prepared at different ratios using pure tin pellets and selenium powder. The glass tube containing mixe...
ABSTRACT Various elements and compounds have been studied to fabricate thin film semiconductors for the solar cell applications. Apart from the materials used in the cell fabrication, the performance of solar cell also depends on the technique used and deposition parameters.In this research,the performance of the p-n junction solar cell is improved by depositing thin films at optimized deposition temperature. The optical and electrical behavior of thin films was analyzedundervariedchemical co...
As the future size of phase change random access memory is scaled down, its reliability in data retention, archival life and power consumption is often disturbed by problems such as elemental segregation and compositional variation caused by repetitive phase transformation. These phenomena are closely related to the crystallization kinetics under various environments. The crystallization kinetics at low temperature and slow transition rates of SnxSey thin films have been investigated usi...
Abstract Thin films of SnO2:Al and ZnO: Al were deposited under different deposition parameters. Effect of substrate temperature, Carrier gas pressure, substrate to nozzle distance and doping percentages were investigated to obtain optimum conditions for deposition of p-SnO2:Al for LED applications. Optimized film of SnO2:Al was deposited at temperature of 408 o C, nozzle substrate distance of 4.75 cm, carrier gas pressure of 1.88 bars and aluminium doping atomic percent of 5.37 %. Solid spec...
ABSTRACT The recent power sector reform in Nigeria has thrown up enormous challenges in this sector, ranging from the construction of more power stations, construction of new transmission lines and substations. The existing network of 8-plants and 26 bus-bars expanded to the proposed network of 16 generating plants with 49 bus-bars. This network expansion requires reappraisal for power evacuation capabilities, relay systems setting and establishment of stability margins for adverse system fa...
ABSTRACT This work analysed the current state of power system in Nigeria with emphasis on distribution system using Akwa Ibom Distribution System as a case study. The components of the study system were analyzed. This work adopted the analytical and simulation approach to reliability and stability assessment. Analysing the system the way it is shows that the system was not reliable and stable. The outcome gotten from the base state of the system confirmed this. The results for the current st...
ABSTRACT The basic idea deals with detecting the voltage collapse ahead of time to provide the operators a lead time for remedial actions and for possible prevention of blackouts. To detect cases of voltage collapse, pattern recognition in conjunction with power system simulator for engineering (PSSE) program was created and then deployed in Nigeria 330KV integrated power system to develop Regularized Least Squares Classification (RLSC) as well as Classification and Regression Trees (CART) h...
ABSTRACT The goal of this project was to design a data logging interface using wireless network principle in order to facilitate the process of monitoring physical parameters such as temperature, pressure, humidity, e.tc in the environment. There is a growing desire to find an efficient and cost effective means to monitor these physical parameters, especially at home and industries. The absence of a means to monitor these quantities in an environment has led to so many inadequacies. The meth...
ABSTRACT The word “vote” means to choose from a list, to elect or to determine. The main goal of voting (in a scenario involving the students of a given tertiary institution), is to come up with student-leaders of the students’ choice.Most tertiary institutions, FUTO not an exception have problems when it comes to voting. Some of the problems involved include rigging votes during election, insecure or inaccessible polling arena, inexperienced personnel and so on because voting in these...