PURKH (E-Journals)
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Geothermal Heat Pump Potential and Prospect for Energy Efficient, Sustainable Development, and the Environment
Get PDFSome emphasis has recently been put on the utilisation of the ambient energy from ground source and other renewable energy sources in order to stimulate alternative energy sources for heating and cooling of buildings. Exploitation of renewable energy sources and particularly ground heat in buildings can significantly contribute towards reducing dependency on fossil fuels. This section highlights the potential energy saving that could be achieved through use of ground energy source. This study highlights the energy problem and the possible saving that can be achieved through the use of ground sources energy. Also, this study clarifies the background of the study, highlights the potential energy saving that could be achieved through use of ground energy source and describes the objectives, approach and scope of the thesis. It also focuses on the optimisation and improvement of the operation conditions of the heat cycles and performances of the GSHP. It was recommended that GSHPs are extendable to more comprehensive applications combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors. Therefore, an approach is needed to integrate renewable energies in a way to meet high building performance. However, because renewable energy sources are stochastic and geographically diffuse, their ability to match demand is determined either by the utilisation of a greater capture area than that occupied by the community to be supplied or the reduction of the community’s energy demands to a level commensuratable with the locally available renewable resources
The The Use of Recycled Aggregates and Used Tyres As Replacement of Natural Aggregates for Flood Wall
No full textWaste materials that are not biodegradable often cause disposal problem and environmental pollution. The use of recycled aggregates (RA) as replacement natural aggregates (NA) in concrete is a sustainable industry alternative. However, there is lack of use of RA as a substitute to NA as a structural material in the construction industry, and this is more so in its application as a construction material to build flood wall to retain water. Thus, this project has been carried out in the laboratory to test the compressive strength, workability and permeability strength of the formulated RA and design a flood wall model using RA to demonstrate its uses in retaining water. The aggregates used in the investigation comprises of 80% used aggregates and 20% recycled tires as replacement of the coarse and fine aggregates for structure material for flood wall. Suitability of concrete using the used aggregates and vehicle tires to cast concrete in the flood wall model has shown positive results. It is suggested that other than its application in flood wall, the concrete using used aggregates and used vehicle tires to replace natural aggregate can also be used in lightweight structures and in construction where lower strength of concrete can be applied
Annual Reviewer Acknowledgement
No full textThe Editorial team of the journal would like to thank the following reviewers for their work in refereeing manuscripts during 201
Cross-Layer Design of Dynamic Link Prediction Power Control Algorithm in Wireless Ad hoc Networks
Get PDFIn wireless communication era, Dynamic Link Prediction based Cross-Layer Power Control Algorithm (DLP-CLPCA) in wireless ad hoc networks provides a joint solution for the power consumption protocol as well as nodes link availability. The Conventional design of ad-hoc network protocols is built on the standard OSI model which has failed to relate with RSS problems, whereas the physical, datalink, network and transport layer has been influenced. Due to this, the early unavailability of nodes occurs and frequent route break during the transmission. To overcome the constraint, developed the Dynamic Link Prediction based Cross-Layer Power Control Protocol to forecast the route earlier maximizes the link availability and create the optimum routing path during the transmission. The proposed link prediction algorithm is implemented in NS-2 simulator with the performance metrics as throughput, delay and energy consumption as a parameter values
Investigation of the Current-Voltage Characteristics of CdS/CdTe-Based Solar Cells Using Model Calculations
Get PDFCdTe can be grown as n-type or p-type although the p-type can also be formed by converting n-CdTe to p-CdTe through the well known CdCl2 treatment, which is an important step taken to improve the conversion efficiency of CdTe solar cells. However, the assumption by most researchers is that CdTe is always a p-type material and so can only form a p-n junction with its n-CdS counterpart. This is not always the case as n-n heterojunction + Schottky junction can be formed when an n-CdTe is involved, with group I metals such as Au and Cu as back metal contact. In this work, p-n junction model and Schottky junction model are presented. In order to verify the junction type formed by various CdS/CdTe-based solar cells reported in the literature, current-voltage data of these experimental results are simulated with the junction models using MATLAB programming platform and compared so as to find out the junction model that best describes each experimental result. Diode parameters such as ideality factor, barrier height, and series resistance were adjusted during the simulation. The junction models are found to be in good agreement with some of the experimental results
An Infusion Model for The Adoption of Social Media in Nigerian Tertiary Institution
Get PDFThis study aims to understand the trend of social media adoption among youths especially undergraduates of Nigerian tertiary institutions. This study used a questionnaire for identifying the various social media platforms. Also, the study formulated a polynomial function for estimating the number of students who will adopt the use of social media platforms based on the number of years after the year of social media adoption. The results of the study show that the social media platform adopted by Nigerian undergraduate students include: Facebook, Twitter, Instagram, SnapChat, WhatsApp, LinkedIn, WeChat, ResearchGate, Academia and Line. The results show that the most commonly used platforms are: Facebook, SnapChat, Twitter and Instagram while the earliest adopted platforms include: Facebook in 2007, Twitter in 2009 including Instagram and WhatsApp in 2010. The results showed that the infusion model for the adoption of social media was formulated, using a polynomial function with the best fit of the cumulative frequency distribution of the number of users each year. He studies concluded that using the polynomial function of social media infusion, the total number of future adopters of social media can be estimated from the number of years from the year of the adoption of the platform
Diabetic Retinopathy Detection & Segmentation using Color Image Processing
Get PDFDiabetic Retinopathy has become a serious issue in the recent past being one of the primary causes for the loss of vision in diabetic patient. The primary motive of this project is to develop an automated technique for the detection of diabetic retinopathy using fundus images. This project involves the processing of the fundus images especially for the detection of diabetic retinopathy which is confirmed by the presence of microaneurysms, exudates, etc. Here, a novel approach has been adopted to perform image segmentation of all these visible stages in case of diabetic retinopathy and not only determine the stage of diabetic retinopathy but also give some more insights related to the disease. This project is completely done by utilizing the tools of Color Image Processing Viz. Segmentation technique, CLAHE technique, morphological operations, etc. Later, a comparative test was performed to test the correctness of the algorithm using various Diabetic Retinopathy Fundus Images & Normal Fundus Images. The algorithm seems to be at par with other approaches used in the modern world today to solve the problem of Diabetic Retinopathy and enables speedy diagnosis by doctors.  
Cyber Physical Systems: The Role of Machine Learning and Cyber Security in Present and Future
Get PDFToday’s technology are changing very rapidly and making an important place in the heart of humans. For example, when internet connected things after connect with other devices, they make a big system which solve complex problems and make people life easier and longer to live. One of biggest/ popular revolution of technology is “Cyber Physical System”. Cyber Physical systems (CPSs) are the systems/ mechanism which are controlled and monitored remotely. CPSs system work with connecting other systems through Internet and its users (by computer-based algorithms). In near future in Industry 4.0 revolution, the uses of cyber physical systems will be on top position. Using such systems give invitation to attackers for performing attacks. But, an attacker can harm a physical and cyber space easily, i.e., affecting physical processes will affect computations (also efficiency of CPS systems). For example, nuclear facilities were affected in 2010 (in Iran) by poplar attack “Stuxnet”. Also, an attacker can control a medical device remotely which will be affected the condition of patients (also will leak private information of patient/ hospital employee). Such serious concerns are being highlighted in this article using machine learning and cyber security frequently (time to time) or an alternative schedule. Maintaining such system is really a difficult task, so if do we can save a lot of energies and unwanted attacks, etc., in overall. Hence, this article is being written with considering future serious concerns and challenges with CPSs, and listing out of such critical issues one by one (in detail)
Spherical Shock Waves of Variable Energy in A Radiating Atmosphere
Get PDFThis paper presents power series similarity solutions for spherical shock waves of variable energy propagating in a radiating gas, taking into consideration the Rosseland’s radiative diffusion model. These similarity solutions are obtained for an energy input , where is the energy released up to time t and is a functional constant. The effects of radiation-parameter are explored on the pressure, the density, the particle velocity and the heat flux of radiation just behind the spherical shock front. The results provided a clear picture of whether and how the radiation flux affects the distribution of the flow variables in the region behind the spherical shock waves
Mixing of Ejected Material in Supernova Remnant Cas A
Get PDFCas A is the well known supernova remnant and detailed observational data have been accumulated. In particular, recent observations suggest that the element distributions for silicon (Si) and iron (Fe) are very peculiar: Fe locates in front of Si. On the other hand, the distribution has not been well studied in connection with supernova remnants. Therefore, we investigate the formation of the remnant of Cas A. Hydrodynamical calculations are performed from the beginning of explosion to the present stage. Before the explosion, models of circumstellar matter are constructed, where the matter is assumed to be ejected from a progenitor. As the supernova simulation of explosion, two dimensional hydrodynamical calculations are performed. It is found that the Rayleigh-Taylor instability is developed from the boundary between hydrogen and helium layers.The instability between Si and Fe layers is not grown enough to induce the observed matter mixing if only the mass loss is included during the red super giant stage. We suggest that an instability at the boundary between Si and Fe layers ascribed to the mass loss during the Wolf-Rayet stage could explain the observations