7,641 research outputs found

    Evaluation of facilities performance on students’ satisfaction in Northern Nigerian Universities

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    Performance evaluation of academic facilities of HEIs is very critical to educational effectiveness. Presently, there is limited or no research/data in Nigeria to assess how extensively the use of or lack of academic facilities benchmarking practices. The aim of this research was to develop a facilities performance framework for HEIs academic facilities in order to serve as a reference model for policy makers while designing HEIs facilities standard targeted towards improving facilities performance for enhanced student satisfaction. Quantitative research approach using survey design was adopted. Data was collected using closed-ended questionnaires distributed to a sample of 1000 student randomly selected from three universities in the northern Nigeria out of which 735 were considered valid for the analysis. Research questions were answered by testing the proposed research hypothesis which were developed for the research. The descriptive analyses were conducted using the Statistical Package for Social Science Software (SPSS version 23) while the inferential statistics were analyzed using a Partial Least Squares Structural Equation Modelling software (SmartPLS version 3.0). Overall, the result found that facilities performance significantly influenced student satisfaction. The R-square value indicated that performance of the HEIs component facilities explained 63 percent of the variance in students’ satisfaction. Furthermore, it was found that 66.7 percent of the performance of HEIs components facilities was explained by the performance of both physical and non-physical facilities that constitutes the HEIs academic facilities. The implication of this results points to the importance of including students’ feedback in the facilities management aspect of HEIs. This is for the fact that students’satisfaction was shown to be significantly related to the condition of the university facilities. It is recommended that future research should focus on identifying students satisfaction with academic facilities in the HEIs using experience as a measure of facilities performance to promote the concept of best practices benchmarking for the institutions to esterblished quality facilities in their institutions

    Development and optimization of zeolite synthesis route from natural koalin for adsorption of dyes

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    Synthesis of zeolite using kaolin as the main source of alumina and silica has been identified as a novel zeolite production process, which could reduce the cost of using the synthetic reagents and the high energy consumption. A low grade kaolin was used for studying the most suitable synthesis route and operating parameters for producing a high yield and pure phase zeolite. The study adopted the alkaline activation and microwave assisted heating as modification techniques of the conventional hydrothermal synthesis process. Calcination and crystallization proceses were identified as the bottleneck operations within the process. Hence, this study employed 2k factorial design of experiment to study the relationship of metakaolinization temperature of 600 – 800 oC with calcination time of 1 – 5 hours. And that of crystallization time of 9 – 16 hours with aging treatment time of 12 – 36 hours. Central Composite Design (CCD) is used for optimization with axial and center point for factors evaluation towards the responses; yield percent (%) and crystallinity (%) for crystallization process. Based on the Response Surface Methodology (RSM), with desirability value of 98.67 %, the significant parametric aging condition is 27 hours and crystallization time is 9 hours were suggested to yield an optimum product for 80.47 yield percent and 76.92 crystallinity. Three confirmation runs were performed based on the suggested optimum parameter and the calculated error value was found to be below 10 %. The synthesized zeolite-A from the confirmation runs was characterized through XRD. The results were then corroborated with the analytical results from SEM, BET and FTIR. The activity of the synthesized zeolite A was confirmed by a structural refinement analysis, that identified the product as a member of the cubic crystalline systems, belonging to a Fm3c space group with lattice cubic structure values where

    Directive ultra wideband antenna for medical applications

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    Since the acceptance of unlicensed band of Ultra-Wideband (UWB) technology in the range between 3.1 and 10.6 GHz, the realization of low-cost UWB wireless systems is considered a fundamental research goal both for military and commercial applications. The possible use and benefits of UWB technology are significant among its potential applications, high-resolution radar and short-range ultra-high speed data transmission. However, one of the most critical challenging task of the UWB system is the designing of a compact size antenna that possess a good gain and high directivity. Thus, the aim of this project is to design and develop a directive and miniaturized antenna for UWB applications. The antenna is designed and fabricated on a Flame Retardant (FR4) laminated substrate with dielectric constant, Ô‘r of 4.3 and thickness of 1.6mm. Several numbers of antennas have been carried out throughout the completion of the project. Firstly, an antenna with slots on radiator has been designed. Subsequently, Ground Defected Structure (DGS) is implemented. For increasing bandwidth and impedance matching of the first antenna, thus an antenna with compact dimension of 25Ă—45mm2 has been resulted. Finally, a reflector structure with the distance of 18mm is added for directivity and gain enhancement. The antenna with reflector has been fabricated using etching technique and being measured for the reflection coefficient. As the result, by applying reflector, the directivity and gain of the antenna has increased significantly, from 5.81dBi to 7.06dBi. This showed 21.52% gain improvement of the proposed antenna by implementing reflector. Therefore, the proposed antenna which has compact size and high gain is seen as a suitable candidate for the use of UWB applications

    A robust digital image watermarking using repetition codes against common attacks

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    Digital watermarking is hiding the information inside a digital media to protect for such documents against malicious intentions to change such documents or even claim the rights of such documents. Currently the capability of repetition codes on various attacks in not sufficiently studied. In this project, a robust frequency domain watermarking scheme has been implemented using Discrete Cosine Transform (DCT). The idea of this scheme is to embed an encoded watermark using repetition code (3, 1) inside the cover image pixels based on Discrete Cosine Transform (DCT) embedding technique. The proposed methods have undergone several simulation attacks tests in order to check up and compare their robustness against various attacks, like salt and pepper, speckle, compress, Gaussian, image contrast, resizing and cropping attack. The robustness of the watermarking scheme has been calculated using Peak Signal-To-Noise Ratio (PSNR), Mean Squared Error (MSE) and Normalized Correlations (NC). In our experiments, the results show that the robustness of a watermark with repetition codes is much better than without repetition code

    Design a photovoltaic system based on maximum power point tracking under partial shading

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    Photovoltaic systems have been given special attention given their long-term potential advantages. Solar panels can produce maximum power at specific operating points called maximum power points (MPP). Solar panels must work at this particular stage in order to ensure that solar panels produce maximum power and maximize efficiency. The performance of the solar photovoltaic unit is strongly affected by the level of radiation, heat and partial shading condition. The partial shedding condition is one of vectors that can affect the PV cell performance. To overcome on this problem, this project proposes photovoltaic system based on maximum power point tracking of partial shading condition. The MPPT algorithm has many methods like P&O and PSO. P&O it had limitation that is not capable to cover the multi-peaks curves. Beside that the PSO method is more effective in partial shading condition. The voltage and current of MSX60 PV module are subjected to various insolation conditions. The Particle Swarm Optimization (PSO) algorithm based MPPT has been implemented to track maximum power partial shading condition. So, in normal condition the power reach 245 W which is higher than the power under partial shading condition that reach 100 W. The PV module is designed using MATLAB/SIMULINK. The accurateness of this simulator is verified with PV module, the result is practiced during normal condition and under partial shading condition meanwhile, multiple curves of I-V and P-V will produce during normal condition and partial shading condition

    Design and economic analysis of solar home system for urban areas of Mogadishu using homer software

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    In this century of enhanced progress by various spaces, some African states are still challenging lack of energy due to scarcity in some places. The most used energy (generation of electricity) is hydropower because heat and fuel are still on some scale. This problem comes about in less efficiency and financial decay of some nations such as Somalia which is among the country at very high speed in progress, the grid lines from distant places are stack and they are rare matched to the required of power in all areas of the nation, especially in remote or urban areas where each household needs electricity utilization instead of utilizing local, conventional and lighting at domestic. This issue can be illuminated utilizing other elective sources of renewable energy for provincial electrification such as Photovoltaic systems. Hence, this project basically focuses on the design of SHS that incorporate financial assessment and utilize of an individual SHS of 200W, so that the satisfaction of the people and the targets of the country can be effectively achieved. Under this project, the dedicated on the investigation of power utilization based on single house household family SHS has been taking a case study of one village in Mogadishu Somalia named Heliwaa placed in Benaadir region. The survey was conducted by assessing the average major load conditions for consecutive hours per day based on photovoltaic capacity. The purpose of this study was achieved the optimal size of the photovoltaic panel and the battery capacity that can be used to power the home. Ultimately, designed project and cost will be compared to other private sector electricity cost, it means which one is more reliable and economically for electricity generation. Therefore according to, the findings the cost of energy is 2.614 in $/KWh which is lower than the private sector. This was considered optimum solution. In this project the design and simulation tasks was achieved through the assistance of HOMER software. The electrification and economics information on combination of photovoltaic systems, in the form of SHS and other renewable energy like stand-alone systems, to provide a reliable and economic system

    Resonant states in double and triple quantum wells

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    The full set of resonant states in double and triple quantum well/barrier structures is investigated. This includes bound, anti-bound and normal resonant states which are all eigensolutions of Schrodinger's equation with generalized outgoing wave boundary conditions. The transformation of resonant states and their transitions between different subgroups as well as the role of each subgroup in observables, such as the quantum transmission, is analyzed. The quantum well potentials are modeled by Dirac delta functions; therefore, as part of this study, the well-known problem of bound states in delta-like potentials is also revisited.Comment: 10 pages, 11 figure

    Looking Inwards for Sustainability: Nigerian Cities and Building Demolition-waste or wealth?

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    Cities could generally be described as sustainable before the replacement of manual labour with machines known as the industrial revolution of the 18th century in Europe. Nevertheless, the Industrial Revolution has been associated with environmental degradation and other negative impacts. The trend continued for two centuries until it was realised that there is a limit to the capacity of the earth to withstand such impacts. The damage to the earth needs to be halted by choice or forced by natural consequences. The idea of pursuing economic development with minimum negative socio-economic and environmental impacts comes to be known as Sustainability. The built environment becomes at the centre of the sustainability agenda due to the enormous negative impact to the environment. Moreover, it was reported that 90% of all materials resources ever extracted might be used in the built environment. Unfortunately, many of these materials, including 10% unused are discarded as wastes. In the UK example, 90-120 million tonnes of construction and demolition (C&D) waste is generated annually. This makes C&D wastes even more critical to the sustainability agenda; and in search for solution, in the words of Janine Benyus, it may even involve the urban westerners learning from the wisdom of the preindustrial societies that have been living in harmony with the nature. In the preindustrial community of Kano in Nigeria, there is virtually zero C&D waste; rather it is merchandise. The different categories of the stakeholders were interviewed to establish how the system works, the conditions that led to its emergence, and limitations. It was discovered that the end-of-life management of buildings in Kano is a naturally evolved industrial ecology analogous to the natural ecological system, whereby the bye-product of one process becomes the raw material for another with no waste. Furthermore, a conceptual model of the system was developed using the biomorphic adaptation of the shell of an African snail. It was therefore argued that sustainability practices are inherent within the African traditions rather than to be learnt from outside
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