Browsing by Author "Abdulkarim, Abubakar"

Now showing 1 - 10 of 10
  • Item
    Effect of Membership Functions and Data Size on the Performance of ANFIS-Based Model for Predicting Path Losses in the VHF and UHF Bands
    (Journal of Engineering Research (JER) - Kuwait University, 2021-10) Surajudeen-Bakinde, N. T.; Faruk, Nasir; Abdulkarim, Abubakar; Oloyede, Abdulkarim A.; Olawoyin, Lukman A.; Popoola, Segun I.; Sowande, Olugbenga; Adetiba, Emmanuel
    Today, the world is technology-driven and so of these technologies are driven using wireless systems. Signal coverage and quality of service are pertinent for network providers and path loss prediction is very important in the design and planning of these systems. However, the inefficiency of conventional propagation models, such as empirical, deterministic and theoretical models has been established in previous research works. The machine learning methods have recently been applied for prediction of path losses. The Adaptive Neuro-Fuzzy Inference System (ANFIS) technique is one of the machine learning techniques that has been successfully employed to predict path losses in different environments. However, the performance of the ANFIS-based models in terms of the computational complexity and accuracy depends on the selection of the appropriate system parameters. This paper, therefore, investigates the effect of number and shape of membership function (MF), and training data size on the performance of ANFIS model for predicting path losses in the VHF and UHF bands in built-up environments. Path loss propagation measurements were conducted in four cities of Nigeria over the cellular and broadcasting frequencies. A total of 17 broadcast transmission and cellular base stations were utilized for this study. From the results obtained, it can be concluded for the broadcasting bands that the generalized bell MF shows better performance with an average RMSE of 3.00 dB across all the routes, followed by gaussian, Pi, trapezoid and triangular MFs in that other with average RMSE values of 3.09 dB, 3.11 dB, 3.16 dB and 3.23 dB respectively. For the cellular systems, Triangular MF outperformed other MFs with the lowest average RMSE. The generalized bell MF was found to be suited for WCDMA band while triangular MF is most suited for GSM band. Furthermore, it can also be concluded that the higher the number of membership functions, the lower the RMSE, whereas, a decrease in the data size leads to a reduction in the RMSE values. The findings of this study would help researchers and network planners to make a more informed decision on choosing appropriate system parameters when modeling ANFIS models for path loss prediction.s
  • Item
    Effects of PV and Battery Storage Technologies on the Optimal Sizing of Renewable Energy Microgrid
    (Universiti Teknologi Malaysia (UTM), 2018-04-16) Abdulkarim, Abubakar; Abdelkaderer, S.M.; Morrow, D. J.; Amuda, S. A. Y.; Madugu, I.S.; Falade, A.J.; Saminu, Sani; Adediran, Y.A.
    This paper presents analyses of the model for the optimum design of standalone hybrid microgrid. The model is developed with the aim of optimizing system component sizing that can reliably satisfy isolated loads. The objective function is to minimize the annual cost of the plant while taking all constraints into consideration. Mixed integer linear programming technique is used to solve the optimization problem. By applying some approximations, the output power of the wind energy conversion system is expressed as a linear function of wind speed. Effects of different PV technologies and the rated power of each unit have been investigated. The results have shown the ability of the proposed model by reducing the cost of energy by 89.35%, 90.26%, 88.3530%, and 89.99% for AP120, ASE 300, KC120 and SAPC165 respectively. In the same way the carbon dioxide emission is reduced by 83%, 82.82%, 82.51% and 73.48 in the same order of the PV modules. Also, the optimal design is sensitive to the rated power of the WECS and SECS, while the benefit-to-cost ratio and payback period are sensitive to the storage technology.
  • Item
    Electroencephalogram (EEG) Based Imagined Speech Decoding and Recognition
    (institution of Applied Materials and Technology Society with the cooperation of Faculty of Engineering, Universitas Riau, Pekanbaru, Indonesia, 2021-05-25) Saminu, Sani; Guizhi, Xu; Zhang, Shuai; Isselmou, Abd El Kader; Jabire, Adamu Halilu; Karaye, Ibrahim Abdullahi; Ahmad, Isah Salim; Abdulkarim, Abubakar
    ĉe recent investigations and advances in imagined speech decoding and recognition has tremendously improved the decoding of speech directly from brain activity with the help of several neuroimaging techniques that assist us in exploring the neurological processes of imagined speech. ĉis development leads to assist people with disabilities to beneėt from neuroprosthetic devices that improve the life of those suffering from neurological disorders. ĉis paper presents the summary of recent progress in decoding imagined speech using Electroenceplography (EEG) signal, as this neuroimaging method enable us to monitor brain activity with high temporal resolution, it is very portable, low cost, and safer as compared to other methods. ĉerefore, it is a good candidate in investigating an imagined speech decoding from the human cortex which remains a challenging task. ĉe paper also reviews some recent techniques, challenges, future recommendations and possible solutions to improve prosthetic devices and the development of brain computer interface system (BCI).
  • Item
    Energy Consumption in Perpetual Wireless Sensor Networks
    (Zaria Journal of Electrical Engineering Technology, Department of Electrical Engineering, Ahmadu Bello University, Zaria, 2020-09-30) Abdulkarim, Oloyede; Lukman, Olawoyin; Faruk, Nasir; Abdulkarim, Abubakar; ABdulrahman, Otuoze
    Abstract: This paper investigates the amount of energy consumed in different configuration for perpetual wireless sensor networks. Wireless Sensor Networks (WSNs) represent an area of networking that become pivotal in many applications. The use of WSNs for the monitoring of environments, habitats as well as systems within industry and healthcare has made WSNs a crucial area of research within recent years. The principles behind WSNs involve the deployment of remote sensing and relay nodes, able to collect and transmit raw data for processing. Applications such as remote environmental monitoring present new challenges such as the prospect of developing networks that can operate perpetually to collect data for as long as possible. Simulation and theoretical analysis were done using the networking simulator DENSE. DENSE is presented to provide insight into what protocols and energy saving techniques can be employed to establish the possible feasibility of constructing PWSN. The results show that mesh is the most realistic due to its energy distribution and optimization over a large area for a great number of nodes; however, a small single hop based network can provide good result for energy consumption and packet success rates.
  • Item
    PERFORMANCE ANALYSIS OF TRANSMIT DIVERSITY CONFIGURATIONS BASED ON OSTBC ALAMOUTI’S EXTENSION
    (Department of Electrical Engineering, Ahmadu Bello University, Zaria, 2021-03) Saminu, Sani; Jabire, Adamu Halilu; Abdulkarim, Abubakar; Ahmed, Yusuf Kola; Iliyasu, Adamu Yau; Salisu, Sani; Karaye, Ibrahim Abdullahi; Ahmad, Isah Salim
    One of the diversity configurations is transmit diversity. It is employed to mitigate multipath fading channel in a time varying channels to improve wireless communication system and make it more reliable. This paper presents a review of diversity techniques and configurations with various signal processing techniques and space time coding system that are mostly employed, diversity combining schemes and analysis of diversity schemes is also exploited. We also proposed a robust space time coding scheme based on orthogonal design by extending the Alamouti’s space time block coding to a higher order diversity and evaluates its performance based on signal to noise ratio (SNR) and bit error rate (BER). The advantage of this transmit diversity is to simplify the hardware requirement by providing a cost effective solution in broadband wireless system with eliminating the need for adopting many antennas at the receiver side
  • Item
    Performance of Extended Alamouti’s Scheme Using Orthogonal Space Time Block Codes
    (Department of Electrical Engineering, Ahmadu Bello University, Zaria, 2020-09) Saminu, Sani; Jajere, Adamu Halilu; Abdulkarim, Abubakar; Ahmed, Yusuf Kola; Karaye, Ibrahim Abdullahi; Ahmad, Isah Salim
    In today’s communication system, satisfying users demand is very challenging and difficult due to the increase in multimedia and internet applications requirement within the limited radio spectrum coupled with multipath fading and interference. Signaling techniques that are robust and efficient need to be investigated and developed. Diversity techniques that used multiple antennas such as space time wireless technology has been proposed to improve the wireless communication in a multipath fading, interference, and signal scattering wireless links. This paper proposed an extended Alamouti’s scheme based on orthogonal space time block code (OSTBC). This proposed scheme is aimed to improve the wireless system efficiency in multipath fading links technique, also it improves the Multiple input multiple output (MIMO) Raleigh fading channel, and minimizes the bit error ratio (BER). The model is developed in MATLAB environment and performance of the model is analyzed in terms of BER vs Signal to Noise Ratio (SNR).
  • Item
    A Review on Optimal Siting and Sizing of D-STATCOM
    (Faculty of Engineering Universitas Riau, Pekanbaru, Indonesia, 2022-02) Wesley, Dansarki Nanly; Abdulkarim, Abubakar; Okorie, Patrick Ubeh; Jabire, Adamu Halilu; Saminu, Sani; Faruk, Nasir; Oloyode, Abdulkarim; Madugu, Ibrahim Sani; Lawan, A. U.; Rosma, Iswadi Hasyim
    The continuous demand for electrical energy by industries and domestic users have stressed the electricity consumption to a high level. Because most components of domestic and industrial systems are made of power electronics devices in their designs. In addition, modern electrical power distribution networks (DNs) are subjected to major disturbances. Consequently, today’s power system is laden with power quality problems such as excessive energy losses, voltage deviations, poor power factor (PF), voltage instability and reliability issues to mentioned just a few. To forestall these disturbances, Distribution Engineers have introduced the use of Custom Power Devices (CPDs) in order to reduce power losses so as improve power quality. Amongst CPDs, Distribution Static Compensator (D-STATCOM) proves most promising in minimizing power quality issues because it generates minimal harmonics, waste less power, has small size, high regulatory capability and cost effective. Researchers in recent years have focused on methodologies required for identifying the most suitable location and rating of D- STATCOM device based on divergent views. However, to date, only one author has so far reviewed a paper on this aspect of study. This paper discusses the latest study on appropriate installation and rating of D-STATCOM techniques for balanced and unbalanced radial distribution networks (UBRDNs). The paper has also provided a comprehensive literature study on the location of DSTATCOM in RDNs for power loss reduction and power quality enhancement. Comparative analyses of various techniques for development of DSTATCOM Objective functions and constraints; Merits and Demerits are presented.
  • Item
    Secure transmission in an unfriendly environment
    (Published by Elsevier BV, 2019-10-01) Lukman A, Olawoyin; Faruk, Nasir; Abdulkarim, Oloyede; Segun, Popoola; Temitayo, Adeniran; Bakinde, Surajudeen; Abdulkarim, Abubakar
    This work investigates and show the performance of destination assisted node in ensuring secure communication in a dual-hop broadcast system. The information transmission occurs between the transmitters which are assumed to be equipped with single antenna through a number of intermediate untrusted relays to the receiver in the presence of multiple passive eavesdroppers. This work assumes that there is no direct link between the transmitter and the receiver and hence, the relay node, receives either the information or noise signal at every transmission processes. Since the transmission occurs in a two-phase, the legitimate receiver is contributing a degrading noise to both the eavesdropper and relay node channels during the first phase while it receives information from the transmitter through the relay during the second phase. Simulation results are used to illustrate the performance of the proposed scheme.
  • Item
    State of the Art in Research on Optimum Design, Reliability and Control of Renewable Energy Microgrids
    (2018-10-01) Abdulkarim, Abubakar; Faruk, Nasir; Abdulkarim, Oloyede; LUkman A, Olawoyin; Segun, Popoola; Abdullateef, Ibrahim; Yinusa, Adeniran
    This paper has presented a comprehensive review in the area of microgrid from the design to implementation. The aim is to evaluate the current status, problems and research efforts toward realising functional microgrids in the power system. The expectations about microgrid are many; therefore the study is divided into three main sections. Recent advancements in the wind energy, solar energy and their future prediction are summarised. States of arts in optimum design of renewable energy microgrid are also investigated. In addition, critical literature review in the reliability analysis of microgrids consisting of renewable energy sources is also reported. Control of microgrids consisting renewable energy sources have been presented. Some examples of existing microgrids across the globe are critically reviewed. The work therefore recommends that energy planners and all stakeholders should consider environmental and regional difference in microgrids planning. Finally, future research areas and directions in these areas are highlighted.
  • Item
    A systematic review and Meta-data analysis on the applications of Deep Learning in Electrocardiogram.
    (Journal of Ambient Intelligence and Humanized Computing., 2022-01-15) Musa, Nehemiah; Gital, Abdulsalam Yau; Aljojo, Nahla; Haruna, Chiroma; Kayode, Adewole; Majeed, Hammed; Faruk, Nasir; Abdulkarim, Abubakar; Ifada, Emmanuel; Yusuf, Folawiyo; Abdulkarim, Oloyede; Lukman, Olawoyin; Sikiru, Ismaeel; Ibrahim, Katibi
    The success of deep learning over the traditional machine learning techniques in handling artificial intelligence application tasks such as image processing, computer vision, object detection, speech recognition, medical imaging and so on, has made deep learning the buzz word that dominates Artificial Intelligence applications. From the last decade, the applica- tions of deep learning in physiological signals such as electrocardiogram (ECG) have attracted a good number of research. However, previous surveys have not been able to provide a systematic comprehensive review including biometric ECG based systems of the applications of deep learning in ECG with respect to domain of applications. To address this gap, we conducted a systematic literature review on the applications of deep learning in ECG including biometric ECG based systems. The study analyzed systematically, 150 primary studies with evidence of the application of deep learning in ECG. The study shows that the applications of deep learning in ECG have been applied in different domains. We presented a new taxonomy of the domains of application of the deep learning in ECG. The paper also presented discussions on bio- metric ECG based systems and meta-data analysis of the studies based on the domain, area, task, deep learning models, dataset sources and preprocessing methods. Challenges and potential research opportunities were highlighted to enable novel research. We believe that this study will be useful to both new researchers and expert researchers who are seeking to add knowledge to the already existing body of knowledge in ECG signal processing using deep learning algorithm.