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The aim of this study is to determine the effect of altering the distance between the light source and the surface of the restorative material (DLR) on the depth of composite cure with a range of low to high light intensity with different types of light cure units. This in vitro study compared the depth of cure obtained with five quartz tungsten halogen and light-emitting diode curing units at different exposure times and light tip-resin composite distances. Resin composite specimens (Tetric Ceram, A3; diameter 4 mm, height 6 mm) were exposed from 1-, 2-, 3-, 4-, and 5- mm distance. The depth of cure determined using the scrape test ISO 4049. Light intensity was also measured at each separation distance for each light. The depth of cure was generally found to decrease as the separation distance increased for all lights at the various cure times. the effect of increasing the separation distance was less than anticipated. The depth of cure was also related to the light output. Depth of composite cure was directly related to intensity and duration of light exposure and inversely related to distance of the light source from the surface for halogen and plasma lights. However, the effect of increasing the separation distance up to 15 mm was less than expected. Altering the separation distance in order to modify the polymerisation characteristics is unlikely to be effective.

An effective management and application of ICT is very important in education nowadays. ICT and e-learning platform plays an important part in the successful implementation of distance, collaborative and e learning for the higher education learners. This approach in the teaching and learning process with the application of ICT culture would create intelligence, academic excellence and quality work life of working adult learners. A good higher education system is required for overall prosperity of a nation. A tremendous growth in the higher education sector had made the administration of higher education institutions complex. Many researches reveal that the integration of ICT helps to reduce the complexity and enhance the overall administration of higher education. This study has been undertaken to identify the various functional areas to which ICT is deployed for information administration in higher education institutions and to find the current extent of usage of ICT in all these functional areas pertaining to information administration. The various factors that contribute to these functional areas were identified. A theoretical model was derived and validated.

Beekeeping is among the livelihood diversification strategies likely affected by climate variability. The variation in temperature and rainfall influence forage phenology impacting on honey production in arid and semi-arid lands (ASALs) in Kenya. The study focused on the relationship between rainfall variability on honey production among the pastoral communities. Rainfall variability was exhibited in the study area in some circumstances drought was experienced annually. On average, 19 plant species were recorded that the bees prefer in the study area. Rainfall variability has significant positive correlation (r=0.423;p=0.00) on the effect on plant phenology thus altering flowering periods of many of the forage plants, changing the foraging behaviour of bees resulting to decrease in honey production. The findings of this study indicate that variation in rainfall has had an adverse effect on honey production and therefore there is need to incorporate land management strategies that will improve honey production in ASALs for sustainable livelihoods among pastoral communities in the context of climate variability.

Nowadays, classroom attendance of a student is a very important task and if taken manually wastes a lot of time. There are many automatic methods available for this purpose i.e., biometric attendance. All these methods waste time, waiting in a queue to detect their thumb, palm, face or iris in front of the scanning device. This paper describes the efficient algorithm that automatically marks attendance without any human intervention and waste of time. The algorithm works with images of multiple faces. Firstly, the images are captured by using a camera placed on the top of the blackboard. The captured images are processed for noise removal using a median filter. Then the faces are detected using the detection algorithm. Lastly, the detected face is recognized by comparing the faces in the database and the attendance is marked. A Graphical User Interface (GUI) is designed for calculating the percentage of the match of faces.

Concrete is the major construction material which plays a vital role in the development of current civilization. Construction and demolition waste is one among the various types of waste materials which can be reused in concrete production. Construction wastes are obtained during construction, renovation and demolition of a building. Dumping of these wastes to landfill causes serious environmental issues. The major factor that affects the quality of recycled coarse aggregate which is obtained from construction and demolition waste is the large amount of cement mortar that remains on the surface of it. Hence, it is essential to determine the properties of concrete containing construction and demolition waste as recycled coarse aggregate (RCA). The objective of this study is to develop the equations in order to predict compressive strength of concrete for different cement content with varying water cement ratio using RCA.

The paper considers the problem of designing ESP curriculum for postgraduate students. The role and potential of ESP teaching has a state meaning for Ukraine and many other countries. The key point in ESP teaching is curriculum design. To design a curriculum, the paper determines the postgraduate students’ needs and formulates certain objectives and tasks for postgraduate ESP study. Four content modules are elaborated involving language materials and four types of speech activity.

The present paper deals with the problem of estimating the finite population variance using two-phase sampling scheme in the presence of random non-response. In this paper, we have suggested some families of factor-type estimators of population variance utilizing the information on an auxiliary variable with unknown population variance. The properties of the suggested families of estimators have been discussed in detail. The optimum estimators of the suggested families have also been pioneered out. The theoretical results have been demonstrated through some real data sets. A simulation study has also been carried out to support the theoretical results.

This study is aimed at estimating the sedimentary thickness of the Upper Benue Trough (Nigeria) as revealed by the Aeromagnetic data using the Spectral Analysis and Euler Deconvolution techniques. The area investigated covers from 090 00’ - 100 00’N and from 110 30’ - 120 30’E. An average sediment thickness of 3.98km was estimated which could favour hydrocarbon accumulation and maturation. There is a NE-SW increase in sedimentary thickness which varied from 2.2km to around 5.2km; it is thickest in the NE region. Verification was performed using the Euler deconvolution method which revealed clusters of Euler depth solutions within the low magnetic zones of interest (between 2km and above 3km). Combining both methods implies that a sedimentary depth of up to 4km (to 5km) could be possible especially in the Yola, Mayo Balewa and Bubila regions which thus increase the probability of hydrocarbon maturation and entrapment in these areas.

In this work, we simulate the global solar radiation received by a horizontal surface and vertical surfaces of different orientations on the ground from theoretical models considering the diffusion and absorption of solar radiation through the atmospheric layer. We have to generate results of the global radiation by the model of Liu and Jordan for thermal systems optimization, particularly in the field of the building in the city of Ouagadougou. This work shows that the solar radiation on a surface, in addition to the seasonal variability, also varies according to the orientation and the inclination of the sun. Thus, in the case of buildings, for example, exposing the large surfaces of the building according to the southern orientation will be avoided in favor of the northern orientation. It is also necessary to consider the scenario of use of the building to situate it in space and time in order to minimize the thermal contributions.

Corrosion inhibition of ethanol stem extract of Costus lucanusianus (ESECL) was studied on mild steel and aluminium by weight loss method. The constituents of the extract identified by Gas Chromatography-Mass Spectroscopy (GC-MS) were forty one (41) compounds with 13-Octadecenal, (Z)-(14.39 %) and 9-Octadecenoic acid, 12-hydroxy-, methyl ester, [R-(Z)]- (11.49 %) as the major compounds. Weight loss method revealed that as the concentration of inhibitor increased, the corrosion rate decreased and inhibition efficiency increased. Maximum corrosion inhibition efficiencies of 91% and 85% were obtained in 1 g/l concentration at low temperatures for mild steel and aluminium, respectively. The adsorption followed physisorption mechanism. Positive values of ?H suggested that the process was endothermic, and negative values of ?S suggested a decrease in the disorderliness of the system from thermodynamic approach. The adsorption model showed that Freundlich adsorption isotherm was the best fit for the process.