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Khalid Yahya

    Khalid Yahya

    Renewable energies are the best solutions to reduce CO2 emissions and supply reliable electricity. This study aims to find the best combination of various components considering economic, environmental, and technical factors together. The... more
    Renewable energies are the best solutions to reduce CO2 emissions and supply reliable electricity. This study aims to find the best combination of various components considering economic, environmental, and technical factors together. The most important consideration factors are the limitation of using PV panels due to the land constraints and applying CO2 penalties where diesel generators and the grid are generating electricity. Findings show that providing electricity by hybrid systems would be useful even in the well-provided electricity regions by the grid with the least blackouts. The best combination of the proposed components, including PV, bio generator, diesel generator, batteries, and grid for the case study region where the load demand is 890 kWh/day and peak load is 167.2 kW, would be an off-grid hybrid system including PV, bio generator, diesel generator, and battery. The optimization results show an NPC (present value of the costs of investment and operation of a syste...
    This study presents the use of a vision-based fuzzy-PID lane-keeping control system for the simulation of a single-track bicycle model. The lane-keeping system (LKS) processes images to identify the lateral deviation of the vehicle from... more
    This study presents the use of a vision-based fuzzy-PID lane-keeping control system for the simulation of a single-track bicycle model. The lane-keeping system (LKS) processes images to identify the lateral deviation of the vehicle from the desired reference track and generates a steering control command to correct the deviation. The LKS was compared to other lane-keeping control methods, such as Ziegler–Nichols proportional derivative (PD) and model predictive control (MPC), in terms of response time and settling time. The fuzzy-PID controller had the best performance, with fewer oscillations and a faster response time compared to the other methods. The PD controller was not as robust under various conditions due to changing parameters, while the MPC was not accurate enough due to similar reasons. However, the fuzzy-PID controller showed the best performance, with a maximum lateral deviation of 2 cm, a settling time of 12 s, and Kp and Kd values of 0.01 and 0.06, respectively. Over...
    Multi-level inverters (MLIs) have been widely used in recent years due to their various advantages in industrial and grid-connected applications. Traditional MLI topologies are being hampered by the rapid surge of renewable energy systems... more
    Multi-level inverters (MLIs) have been widely used in recent years due to their various advantages in industrial and grid-connected applications. Traditional MLI topologies are being hampered by the rapid surge of renewable energy systems (RES) as a result of performance difficulties such as poor power reliability, an economically unviable structure, and a lack of efficiency. These difficulties are due to the traditional MLI topologies’ inability to keep up with the increasing demand for RES. Because of concerns about performance and limitations posed by classic MLI topologies, researchers have found themselves driven to the idea of building innovative hybrid MLI topologies. This study provides a comprehensive analysis of multilevel inverter systems that are wired into the main power supply. Grid-connected inverter types and their configurations are discussed in depth in this review. Diverse multi-level inverter topologies, as well as the different approaches, are divided into vario...
    This paper presents a simple mathematical and Simulink model of a two-phase hybrid stepper motor, where ignoring the permeance space harmonics of the hybrid stepper motor is regarded as the main physical assumption in this article.... more
    This paper presents a simple mathematical and Simulink model of a two-phase hybrid stepper motor, where ignoring the permeance space harmonics of the hybrid stepper motor is regarded as the main physical assumption in this article. Moreover, the dq transformation method is adopted as the main mathematical approach for the derivation of the proposed model, where simple voltages, currents, and torque equations are obtained and used to build the proposed Simulink and circuit model of the stepper motor. The validity and the effectiveness of the proposed model are examined by comparing its results with the results collected from the Simulink model in the library of Matlab. The obtained simulation results showed that the proposed model achieved a high simplicity and high accuracy when compared with conventional models.
    Given the massive potentials of 5G communication networks and their foreseeable evolution, what should there be in 6G that is not in 5G or its long-term evolution? 6G communication networks are estimated to integrate the terrestrial,... more
    Given the massive potentials of 5G communication networks and their foreseeable evolution, what should there be in 6G that is not in 5G or its long-term evolution? 6G communication networks are estimated to integrate the terrestrial, aerial, and maritime communications into a forceful network which would be faster, more reliable, and can support a massive number of devices with ultra-low latency requirements. This article presents a complete overview of potential 6G communication networks. The major contribution of this study is to present a broad overview of key performance indicators (KPIs) of 6G networks that cover the latest manufacturing progress in the environment of the principal areas of research application, and challenges.
    Wireless Power Transfer (WPT) technology can transfer electrical energy from a transmitter to a receiver wirelessly. Due to its many advantages, WPT technology is a more adequate and suitable solution for many industrial applications... more
    Wireless Power Transfer (WPT) technology can transfer electrical energy from a transmitter to a receiver wirelessly. Due to its many advantages, WPT technology is a more adequate and suitable solution for many industrial applications compared to the power transfer by wires. Using WPT technology will reduce the annoyance of wires, improve the power transfer mechanisms. Recently, the WPT gain enormous attention to charging the on-board batteries of the Electric Vehicle (EV). Several well-known car manufacturing companies start efforts to adopt WPT technology and enhance its features. Therefore, WPT can be achieved through the affordable inductive coupling between two coils named a transmitter and a receiver coil. In EV charging applications, transmitter coils are located underneath the road, and receiver coils are installed in the EV. The inductive WPT of resonant type is generally applied to medium-high power transfer applications like EV charging because it achieves better energy ef...
    The rapid advancements in smart grid (SG) technology extend a large number of applications including vehicle charging, smart buildings, and smart cities through the efficient use of advanced communication architecture. However, the... more
    The rapid advancements in smart grid (SG) technology extend a large number of applications including vehicle charging, smart buildings, and smart cities through the efficient use of advanced communication architecture. However, the underlying public channel leads these services to be vulnerable to many threats. Recently, some security schemes were proposed to counter these threats. However, the insecurities of some of these schemes against key compromise impersonation (KCI) and related attacks or compromise on efficiency calls for a secure and efficient authentication scheme for SG infrastructure. A new scheme to secure SG communication is presented in this article to provide a direct device-to-device authentication among smart meter and neighborhood area network gateway. Designed specifically to resists KCI and related attacks, the proposed scheme is more secure and completes the authentication procedure by using the least communication cost as compared with related schemes, which is evident through security and efficiency comparisons.
    Recently, in 2019, Kumar et al. (IEEE Transactions on Smart Grid 10.4 (2018): 4349–4359) proposed an ECC based lightweight authentication and Key agreement scheme (LAKA) to secure the communication among a smart meter (SM) and a... more
    Recently, in 2019, Kumar et al. (IEEE Transactions on Smart Grid 10.4 (2018): 4349–4359) proposed an ECC based lightweight authentication and Key agreement scheme (LAKA) to secure the communication among a smart meter (SM) and a neighbourhood area network (NAN) gateway. The LAKA scheme was proved as secure and efficient as per the comparisons performed by Kumar et al. Specifically, it was argued through security analysis that LAKA provides anonymity and resistance to related attacks. However, the specific analysis in this paper contradicts their claim and it is shown here that in addition to ephemeral secret leakage attack and lack of untraceability, the LAKA is also vulnerable to stolen verifier attack.
    Although Libya has a massive potential of renewable energy (RE) resources particularly solar energy, the country suffers from a shortage of electrical energy and experiences frequent blackouts. The dominant preventive action taken by the... more
    Although Libya has a massive potential of renewable energy (RE) resources particularly solar energy, the country suffers from a shortage of electrical energy and experiences frequent blackouts. The dominant preventive action taken by the grid operator is to shed loads. The main two reasons for the limited RE projects are the highly subsidized electricity tariff and the absence of clear energy legislation. As a solution for the electrical energy deficit, this paper proposes the grid-connected photovoltaic (GCPV) power systems to be installed as distributed generations. The case study is based on a 1 MWp GCPV system designed for Benina International Airport (BIA) in Benghazi. Besides satisfying the electrical demand of the airport, the system can also export its energy directly to the electrical grid where the residential and commercial loads. The analysis was carried out by using PVSyst software. Four PV technologies were simulated for the installation for the sake of performance comparison under Benghazi's weather condition. It was concluded that cadmium telluride (CdTe) outperforms other technologies with 4.79 kWh/kWp/day of produced energy and a performance ratio (PR) of 78.11%. The project can be a successful showcase clean energy producer and a business model which can encourage the individuals and the governmental utilities to implement the solar PV technology for both electricity demand satisfaction as well as a profitable investment.
    Researchers have found many similarities between the 2003 severe acute respiratory syndrome (SARS) virus and SARS-CoV-19 through existing data that reveal the SARS's cause. Artificial intelligence (AI) learning models can be created... more
    Researchers have found many similarities between the 2003 severe acute respiratory syndrome (SARS) virus and SARS-CoV-19 through existing data that reveal the SARS's cause. Artificial intelligence (AI) learning models can be created to predict drug structures that can be used to treat COVID-19. Despite the effectively demonstrated repurposed drugs, more repurposed drugs should be recognized. Furthermore, technological advancements have been helpful in the battle against COVID-19. Machine intelligence technology can support this procedure by rapidly determining adequate and effective drugs against COVID-19 and by overcoming any barrier between a large number of repurposed drugs, laboratory/clinical testing, and final drug authorization. This paper reviews the proposed vaccines and medicines for SARS-CoV-2 and the current application of AI in drug repurposing for COVID-19 treatment.
    Machine learning techniques will contribution to making Internet of Things (IoT) applications that are considered the most significant sources of new data in the coming future more intelligent, where the systems will be able to access raw... more
    Machine learning techniques will contribution to making Internet of Things (IoT) applications that are considered the most significant sources of new data in the coming future more intelligent, where the systems will be able to access raw data from different resources over the network and analyze this information in order to extract knowledge. This study focuses on supervised machine learning techniques that is considered the main pillar of the IoT smart data analysis. This study includes reviews and discussions of substantial issues related to supervised machine learning techniques, highlighting the advantages and limitations of each algorithm, and discusses the research trends and recommendations for further study.
    The mobile cloud computing (MCC) refers to an infrastructure that integrates cloud computing and mobile computing, and it has changed a great deal, the service provisioning of applications, which requires to get the data processed after... more
    The mobile cloud computing (MCC) refers to an infrastructure that integrates cloud computing and mobile computing, and it has changed a great deal, the service provisioning of applications, which requires to get the data processed after collection from vast sensor and Internet-of-Things-based network. The ever increasing number of handheld mobile gadgets has exacerbated the need for robust and efficient authenticated key agreements. We could witness a number of MCC-based multiserver authentication schemes lately to foster the secure adaptation of the technology; however, the demonstrated solutions are either insecure or employing too costly bilinear pairing operations for implementation. In view of limitations, as illustrated in previous studies, we propose a novel pairing-free multiserver authentication protocol for MCC environment based on an elliptic curve cryptosystem that is not only efficient, but also free from security loopholes as demonstrated. The performance evaluation section discusses and distinguishes the findings among latest studies. The strength of the contributed scheme is proved theoretically under formal security model.
    The advancements in the internet of things (IoT) require specialized security protocols to provide unbreakable security along with computation and communication efficiencies. Moreover, user privacy and anonymity has emerged as an integral... more
    The advancements in the internet of things (IoT) require specialized security protocols to provide unbreakable security along with computation and communication efficiencies. Moreover, user privacy and anonymity has emerged as an integral part, along with other security requirements. Unfortunately, many recent authentication schemes to secure IoT-based systems were either proved as vulnerable to different attacks or prey of inefficiencies. Some of these schemes suffer from a faulty design that happened mainly owing to undue emphasis on privacy and anonymity alongside performance efficiency. This article aims to show the design faults by analyzing a very recent hash functions-based authentication scheme for cloud-based IoT systems with misunderstood privacy cum efficiency tradeoff owing to an unadorned design flaw, which is also present in many other such schemes. Precisely, it is proved in this article that the scheme of Wazid et al. cannot provide mutual authentication and key agre...
    An application of phase-angle-difference based algorithm with percentage differential relays is presented in this paper. In the situation where the transformer differential relay is under magnetizing inrush current, the algorithm will be... more
    An application of phase-angle-difference based algorithm with percentage differential relays is presented in this paper. In the situation where the transformer differential relay is under magnetizing inrush current, the algorithm will be utilized to block the process. In this study, the technique is modeled and implemented using Simulink integrated with MATLAB. The real circuit model of power transformer and current transformers are considered in the simulation model. The results confirmed the effectiveness of the technique in different operation modes; such as, magnetizing inrush currents, current transformers saturation and internal transformer faults.
    This paper evaluates the impact of multi-5G small cell systems on the energy efficiency (EE) in a Fifth Generation (5G) of cellular networks. Both the proposed model and the analysis of the EE in this study take into account (i) the path... more
    This paper evaluates the impact of multi-5G small cell systems on the energy efficiency (EE) in a Fifth Generation (5G) of cellular networks. Both the proposed model and the analysis of the EE in this study take into account (i) the path losses, fading, and shadowing that affect the received signal at the user equipment (UE) within the same cell, and (ii) the interference effects of adjacent cells. In addition, the concepts of new technologies such as large MIMO in millimeter range communication have also been considered. The simulation results show that the interference from adjacent cells can degrade the EE of a multi-cell cellular network. With the high interference the number of bits that will be transferred per joule of energy is 1.29 Mb/J with a 0.25 GHz bandwidth and 16 transmit antennas. While, with a 1 GHz bandwidth the transfer rate increases to 5.17 Mb/J. Whereas, with 64 transmit antennas the EE improved to 5.17 Mb/J with a 0.25 GHz BW and 20.70 Mb/J with a 1 GHz BW. The...
    Since about 1980, a new generation has appeared approximately every decade. Mobile phones started with first-generation (1G), then the successful second generation (2G), and then mixed successful auctions since the launch of 3G. According... more
    Since about 1980, a new generation has appeared approximately every decade. Mobile phones started with first-generation (1G), then the successful second generation (2G), and then mixed successful auctions since the launch of 3G. According to business terms, 1G and 2G were providing voice and gradually include data (3G is unsuccessful, 4G is very successful). Today, we are seeing a stir over what 5G will provide. Key expectations currently being discussed include an ultra-high 20 Gb/s bit rate, an ultra-low latency of just 1 millisecond, and a very high capacity. Given the enormous potential of 5G communication networks and their expected evolution, what should 6G include that is not part of 5G or its long-term evolution? 6G communication networks should deliver improved range and data speeds, as well as the ability to connect users from anywhere. This article details possible 6G communication networks. More specifically, the primary influence of this research is to deliver a complet...
    In this paper, perturb and observe (P&O) algorithm is presented to grab the maximum power point from Thermoelectric Generator (TEG) sources. The main contribution of this study relies on estimating the output power of TEG by using... more
    In this paper, perturb and observe (P&O) algorithm is presented to grab the maximum power point from Thermoelectric Generator (TEG) sources. The main contribution of this study relies on estimating the output power of TEG by using Kalman filter to readjust the characteristics of TEG with respect to operating conditions. In the real applications, there is a disturbance appears on the power curve due to the heat distribution on the TEG surfaces. For smooth implementation of the maximum power point tracking (MPPT) algorithm and to overcome the disturbance, Kalman filter is used. It is estimate the output power curve which paves the way for MPPT to be implemented easily in the microcontroller. The feasibility of the proposed harvesting system verified experimentally.
    Thermoelectric generators (TEGs) and their applications have gained momentum for their ability to use waste thermal energy. More contemporary technology must offer more exceptional energy-efficient applications at a lower cost. New... more
    Thermoelectric generators (TEGs) and their applications have gained momentum for their ability to use waste thermal energy. More contemporary technology must offer more exceptional energy-efficient applications at a lower cost. New technology must also have an ability to generate electric power through the conversion of wasted heat. The TEG has demonstrated its efficiency and how it can offer increased potential by adding an MPPT algorithm to increase the power flow while decreasing the cost of operation. The limitations can be offset by the use of lower cost manufacturing materials and automated systems in the TEG units. It is also important to note the cost per watt found in using a thermoelectric generator is estimated to be $1/W for an installed device. To achieve this goal, the optimum operating point should be monitored by DC to DC converters. The DC to DC converters should also be driven through a generated pulse using an MPPT algorithm.
    Machine learning techniques will contribution towards making Internet of Things (IoT) symmetric applications among the most significant sources of new data in the future. In this context, network systems are endowed with the capacity to... more
    Machine learning techniques will contribution towards making Internet of Things (IoT) symmetric applications among the most significant sources of new data in the future. In this context, network systems are endowed with the capacity to access varieties of experimental symmetric data across a plethora of network devices, study the data information, obtain knowledge, and make informed decisions based on the dataset at its disposal. This study is limited to supervised and unsupervised machine learning (ML) techniques, regarded as the bedrock of the IoT smart data analysis. This study includes reviews and discussions of substantial issues related to supervised and unsupervised machine learning techniques, highlighting the advantages and limitations of each algorithm, and discusses the research trends and recommendations for further study.