Papers by Mohammed Almahdi Alsharif
Improving sustainability on university campuses in Saudi Arabia : an assessment of organisational and decision-related opportunities and barriers
Sustainability is a very broad term which encompasses a variety of principles, concepts and pract... more Sustainability is a very broad term which encompasses a variety of principles, concepts and practices -the majority of which are concerned with reducing negative impacts on the natural environmentand encouraging the more judicious and careful utilization of natural resources. For the purposes of this thesis the main aspects of sustainability being focused on, in the context of university campuses, relate primarily to organisational and infrastructural/ technological change -particularly with regard to energy efficiency and the organisation's overall carbon footpri nt. The decision-making approaches associated with (and ramifications of) those changes are also of central interest. To a lesserextent, but still incorporated as part of the research study, is the important issue of social engagement in the adoption of pro-environmental practices at HEIs in Saudi Arabia. The central aim of this PhD is to explore the extent to which planning and action on sustainability by Facilities a...
International Journal of Medical Research and Health Sciences, 2020
Background: Globally, Hepatocellular carcinoma (HCC) is the third leading cause of cancer related... more Background: Globally, Hepatocellular carcinoma (HCC) is the third leading cause of cancer related mortality. There are many reported causes of HCC including chronic hepatitis B virus (HBV), hepatitis C virus (HCV) infection, primary autoimmune hepatitis, hemochromatosis, Budd-Chiari syndrome, and chronic alcohol consumption, which mostly result in liver cirrhosis. Fibrosis and cirrhosis are typically antecedents of HCC. Lack of population awareness may be by itself risk factors for disease and its sequalae. Aim: To assess the general population awareness regarding hepatocellular carcinoma and its risk factors in Southern region, southern of Saudi Arabia. Methodology: A descriptive cross-sectional survey was used targeting all population in Southern region, Saudi Arabia. The study was conducted during the period from February 2020 to May 2020. Data were collected using structured questionnaire included person’s socio-demographic data, Participants’ awareness regarding HCC. The questi...
International Journal Of Community Medicine And Public Health, 2021
When any loss of the tooth structure happens, it’s restoration using different filling materials ... more When any loss of the tooth structure happens, it’s restoration using different filling materials is essential to compensate for the defective parts. Among the most commonly used dental restorative materials, dental amalgam & composite resins prevail. We have searched the relevant studies that compared composite resins and amalgam restorations to review them in different aspects including the clinical, economic, biocompatibility and patients’ perspectives. Regarding the clinical perspective, most of the reviewed investigations showed that composite resin restorations were associated with higher failure rates and developed dental caries more than restorations made by the amalgam alloys. There were no significant differences noticed between the two materials regarding the side effects as both caused nearly similar neurological and renal affection. Based on the findings from previous studies, we could only notice that some studies reported that microalbuminuria may be associated with co...
Journal of Computer Networks and Communications, 2015
Two main concerns for designing a wireless system are more network capacity and less energy consu... more Two main concerns for designing a wireless system are more network capacity and less energy consumption. Recently, distributed antenna system (DAS) has received considerable attention due to its potential to provide higher spectral efficiency (SE) and uniform coverage for cellular networks. In this regard, this paper compares the performance of DAS with centralized antenna system (CAS) in LTE-A system in terms of energy efficiency (EE), where practical restrictions such as out-of-cell interference, path loss, and small scale fading are taken into account. Furthermore, the EE and system power consumption are investigated under three different cell-load scenarios (high, moderate, and low load) where different numbers of antennas are activated and remaining of antennas are under sleep mode. Finally, based on the tradeoff between power-saving and EE, two optimal DAS antenna deployments are proposed for low and moderate cell-load scenarios. The results reveal that DAS considerably outper...
EURASIP Journal on Wireless Communications and Networking, 2015
Cellular network operators are always seeking to increase the area of coverage of their networks,... more Cellular network operators are always seeking to increase the area of coverage of their networks, open up new markets and provide services to potential customers in remote rural areas. However, increased energy consumption, operator energy cost and the potential environmental impact of increased greenhouse gas emissions and the exhaustion of non-renewable energy resources (fossil fuel) pose major challenges to cellular network operators. The specific power supply needs for rural base stations (BSs) such as cost-effectiveness, efficiency, sustainability and reliability can be satisfied by taking advantage of the technological advances in renewable energy. This study investigates the possibility of decreasing both operational expenditure (OPEX) and greenhouse gas emissions with guaranteed sustainability and reliability for rural BSs using a solar photovoltaic/diesel generator hybrid power system. Three key aspects have been investigated: (i) energy yield, (ii) economic factors and (iii) greenhouse gas emissions. The results showed major benefits for mobile operators in terms of both environmental conservation and OPEX reduction, with an average annual OPEX savings of 43% to 47% based on the characteristics of solar radiation exposure in Malaysia. Finally, the paper compares the feasibility of using the proposed approach in a four-season country and compares the results against results obtained in Malaysia, which is a country with a tropical climate.
Cooperation Management Among Base Stations Based on Cells Switch-Off for a Green LTE Cellular Network
Wireless Personal Communications, 2014
The sudden increase in subscribers and demand for high-speed data has prompted cellular operators... more The sudden increase in subscribers and demand for high-speed data has prompted cellular operators to increase the number of base stations to fulfill the needs of mobile subscribers. This increase has subsequently increased the overall energy consumption, operational costs and carbon footprint of cellular networks. Accordingly, improving the energy efficiency of wireless networks has become a compelling challenge for researchers, vendors, and mobile operators, not only to reduce the operational costs, but to also reduce the environmental effects. The focus is on creating green cellular networks at base stations because base stations consume most of the energy. In this paper, we investigate how much energy is saved based on a Long Term Evolution (LTE) network by reducing the number and size of active macro-cells according to traffic load conditions. The proposed methodology is simulated on a set of real-sized LTE networks. The simulation results show that there are savings of up to 48 % in terms of both energy savings and operational expenditure with a 90 % cell coverage condition.
Journal of Computer Networks and Communications, 2013
Energy efficiency in cellular networks has received significant attention from both academia and ... more Energy efficiency in cellular networks has received significant attention from both academia and industry because of the importance of reducing the operational expenditures and maintaining the profitability of cellular networks, in addition to making these networks “greener.” Because the base station is the primary energy consumer in the network, efforts have been made to study base station energy consumption and to find ways to improve energy efficiency. In this paper, we present a brief review of the techniques that have been used recently to improve energy efficiency, such as energy-efficient power amplifier techniques, time-domain techniques, cell switching, management of the physical layer through multiple-input multiple-output (MIMO) management, heterogeneous network architectures based on Micro-Pico-Femtocells, cell zooming, and relay techniques. In addition, this paper discusses the advantages and disadvantages of each technique to contribute to a better understanding of eac...
Energy-efficient subcarrier optimization scheme based on particle swarm for green radio wireless networks
2013 IEEE 11th Malaysia International Conference on Communications (MICC), 2013
The growing awareness towards energy efficient cellular networks has paved way for new technologi... more The growing awareness towards energy efficient cellular networks has paved way for new technologies to enable design towards green cellular networks. According to technical analysts, the base stations are the most energy intensive element in a typical cellular network. Saving power in base stations is therefore the primary focus in green cellular networks. The main goal of designing green base stations is for saving energy and reducing power consumption while guaranteeing service and coverage for users and ensuring the capability of base station for evolution. One cannot ignore the amount of energy that is wasted due to the lack of efficient utilization of resources. This was the main motivation behind this study. This paper aims to exploit the dynamic traffic load conditions to improve the downlink energy consumption by achieving optimal balancing between the number of subcarriers and dynamic traffic load conditions. Particle Swarm Optimization (PSO) has been adopted to optimize the subcarriers under the condition of maximum traffic load while guaranteeing the QOS under the constraint of minimal power per subcarrier. Simulation results show that the annual energy savings that achieved by this approach only for one base station up to 130 kWh. Hence, in a large area with thousands of base stations or even more, the aggregate energy savings could be substantial as well as the annual OPEX saving.
Classification, Recent Advances and Research Challenges in Energy Efficient Cellular Networks
Wireless Personal Communications, 2013
There is a growing interest in improving the energy efficiency of communication networks to reduc... more There is a growing interest in improving the energy efficiency of communication networks to reduce operational expenditures, to maintain profitability and to make cellular networks greener. The revolution of green cellular networks has received significant attention from researchers, vendors, cellular service providers and governments, all of whom play important roles in the success of green networking technology. This paper aims to present a comprehensive overview on current green techniques for wireless networks, highlighting the energy savings that can be achieved by each technique, as well as the challenges faced by these techniques. Additionally, we present a summary of the essential research projects that have recently emerged for green mobile networks and display them as open research issues, thus providing researchers interested in pursuing this vision with the latest update.
Cell-Coverage-Area Optimization Based on Particle Swarm Optimization (PSO) for Green Macro Long-Term Evolution (LTE) Cellular Networks
Bio-Inspired Computation in Telecommunications, 2015
Abstract Energy efficiency (EE) in cellular networks is a growing concern for cellular operators ... more Abstract Energy efficiency (EE) in cellular networks is a growing concern for cellular operators regarding maintaining profitability and reducing their overall environmental impact. Because evolved Node Bs (eNBs) for long-term evolution wireless cellular networks are deployed to accommodate peak traffic, they are underutilized most of the time, especially under low-traffic conditions. Hence, switching eNBs on/off in accordance with traffic-pattern variations is considered an effective method of improving EE in cellular networks. However, two main concerns of network operators when applying this technique are coverage issues and securing radio service for the entire area in response to the increased size of some cells to provide coverage for cell areas that are switched off. This study focuses on the parameters that affect coverage to find a balance between cellular network energy consumption and cell-coverage area. To achieve this goal, particle swarm optimization, a bio-inspired computational method, has been adopted in this study to maximize the cell-coverage area under constraints for the transmission power of the eNB (Ptx), the total antenna gain (G), the bandwidth (BW), the signal-to-interference-plus-noise ratio (SINR), and shadow fading (σ). The results show that this method can achieve daily energy savings of up to 34.77, while guaranteeing full coverage within the cell area.
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Papers by Mohammed Almahdi Alsharif