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Impact of Electronic Publishing in Higher Education Library Services in Nigeria
Ikoro Francisca Mgbechikwere,
Diugo Divinefavour Nkwachi
Issue:
Volume 9, Issue 1, February 2021
Pages:
1-6
Received:
29 July 2020
Accepted:
19 August 2020
Published:
4 January 2021
Abstract: In this fast-changing world, Academic library users seem to have less time for accumulating reading and learning materials. Reading the whole book, articles, and sourcing information traditionally has become a problem. It has become essential for library professionals to provide information to the users within the shortest possible time through electronic resources using the appropriate information and communication technologies [ICTs]. Electronic publishing has become common in knowledge acquisition and it is complimenting printed versions. Besides the web-based resources, there is also much non-network electronic publishing such as Encyclopedias/ Dictionaries/ Directories in CD Rom and DVD, technical and reference publications accessible through mobile phones and other electronic devices. This paper discusses the impact of electronic publishing on academic library services to its users. It conceptualizes the term electronic publishing, identifies the impact of electronic publishing on library services as user satisfaction, mobility and flexibility of information sources, encouraging collaborative work, maintenance and accuracy of publishing works, increased information sources in the library collection, adds value to library services, etc. The paper outlined some benefits and problems of electronic publishing in today's library services. It also discussed the findings observed. The paper is an opinion paper; it investigates the topic using observation research method and available library resources. The significance of this study shows that electronic publishing has come to stay. It will continue to complement the traditional method of library services even become more preferred and relevant in information resources and services rendered in academic libraries.
Abstract: In this fast-changing world, Academic library users seem to have less time for accumulating reading and learning materials. Reading the whole book, articles, and sourcing information traditionally has become a problem. It has become essential for library professionals to provide information to the users within the shortest possible time through ele...
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Techno-economic Feasibility Analysis of an Off-grid Hybrid Renewable Energy System for Rural Electrification
Jamil Ahmed,
Khanji Harijan,
Pervez Hameed Shaikh,
Amjad Ali Lashari
Issue:
Volume 9, Issue 1, February 2021
Pages:
7-15
Received:
16 December 2020
Accepted:
31 December 2020
Published:
12 January 2021
Abstract: The demand for electricity in remote rural areas is a major obstacle to their development. The extension of the grid network to remote rural areas has been identified as a difficult topography for complex constructions and enormous investments. The development of off-grid renewable energy generation technologies offers the opportunity for tackling these challenges. This study provides a techno-economic feasibility analysis of an off-grid hybrid renewable energy system for a rural village of district Kech, Balochistan, Pakistan. The proposed hybrid system integrates the different combinations of the wind turbine, solar PV modules, and battery backups to meet the required electric load demand. The hybrid system is modeled and optimized through a powerful simulation software Hybrid Optimized Model for Electric Renewable (HOMER-Pro). The optimized configuration of the hybrid system consists of wind turbines (12kW), solar PV (103kW), 224 lead-acid batteries (72.4Ah each), and 29.1 kW converters. The simulation results show that the proposed system can meet the power requirements of 197.74kWh/day primary demand load with 27.87kW peak load. This system configuration has the Net Present Cost (NPC) of $127,345 and Cost of Energy (COE) of 0.137$/kWh with a 100% renewable fraction. Furthermore, the results of the present study are compared with the literature and have resulted in a cost-effective hybrid renewable energy system with a low COE.
Abstract: The demand for electricity in remote rural areas is a major obstacle to their development. The extension of the grid network to remote rural areas has been identified as a difficult topography for complex constructions and enormous investments. The development of off-grid renewable energy generation technologies offers the opportunity for tackling ...
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A Single Channel IGBT Gate Drivers for Medium Voltage Converters
Sokchea Am,
Phok Chrin,
Bunthern Kim,
Lim Phing
Issue:
Volume 9, Issue 1, February 2021
Pages:
16-25
Received:
5 February 2021
Accepted:
14 February 2021
Published:
26 February 2021
Abstract: This article treats the gate driver system for IGBT modules in Medium-Voltage (MV) applications. The study focuses principally on two functions of an IGBT gate driver: an impulse signal transmission and a power transmission. For each function, the suitable topology is proposed. Then, for safety and device's protection reason, all gate driver functions must sustain the high and very high galvanic insulation voltage capabilities. For low-cost design, the insulation system can be achieved with the help of the insulating material in a pot core planar transformer. Therefore, for each function, the optimized design of a pot-core transformer and its associated electronics components is performed with the help of a virtual prototyping tool (a genetic algorithm: GA code in MATLABTM). The first section focuses on optimization design of a selected topology for an impulse signal transmission function. A bi-objective (maximize the output voltage vout and minimize the input current imos) problem of this function that leads to a Pareto front is presented. Several Pareto fronts’ results are obtained assuming different insulation layers thickness. The second part focuses on optimization design of a selected topology for a power transmission function. Maximize the converter efficiency (ηcon) and minimize the output power (Pout) are considered as a bi-objective. Thus, numerous Pareto fronts’ results are achieved for a few different insulation thicknesses. Finally, the prototype of a single channel IGBT gate driver is invented to validate the proposed design.
Abstract: This article treats the gate driver system for IGBT modules in Medium-Voltage (MV) applications. The study focuses principally on two functions of an IGBT gate driver: an impulse signal transmission and a power transmission. For each function, the suitable topology is proposed. Then, for safety and device's protection reason, all gate driver functi...
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Efficient Power Utilization Control Scheme for Hybrid Distribution Generation Grid
Mohamed M. A. Mahfouz,
Mohammed Alsumiri,
Raed Althomali
Issue:
Volume 9, Issue 1, February 2021
Pages:
26-32
Received:
16 February 2021
Accepted:
1 March 2021
Published:
4 March 2021
Abstract: Micro Grids (MGs) are well described as distribution systems with integrated distributed energy resources, i.e. photovoltaic (PV) and wind power generation systems. MGs can improve the quality of power by maintaining voltage levels and reducing the cost of energy supply. Despite the obvious advantages of distributed generation, technical operating and controlling challenges related to MGs are immense to maintain voltage and frequency stabilities during variable loading and emergency condition. This paper proposes an efficient an overhaul maximum power conditioning control system of micro grid feeds from PV modules and wind turbine. The PV power system utilizes two-stage energy conversion system topology, i.e. a DC/DC chopper circuit and voltage source inverter (VSI) that satisfies the MG technical requirements. For the proposed PV maximum power point tracking (MPPT), the boost chopper duty cycle is being adjusted to set the PV panel operating point to a maximum power point. Whereas for the proposed wind turbine, the pitch angle controller is developed to force the wind turbine to reaches its optimal operation at low and medium wind speeds. During high wind speeds, the pitch angle is changed to minimize the aerodynamic power. The dynamic model and control of the investigated MG for both transient and steady states operations are illustrated. Furthermore, the control strategies for maintaining the maximum energy conversion and to obtain voltage stability under multiple operating conditions are presented.
Abstract: Micro Grids (MGs) are well described as distribution systems with integrated distributed energy resources, i.e. photovoltaic (PV) and wind power generation systems. MGs can improve the quality of power by maintaining voltage levels and reducing the cost of energy supply. Despite the obvious advantages of distributed generation, technical operating ...
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