Electrical & Electronics Engineering

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Electrical & Electronics Engineering

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Generation of Random Numbers for Data Security Applications
(7th Annual Engineering Conference, 2006-06-28) Usman A.U; Ajiboye, Johnson Adegbenga
In this age of Electronic connectivity, the issue of data security is becoming more and more of great concern. The growth in computer systems and their interconnections via networks has increased the dependence of several organizations and individuals on information stored and communicated using these systems. Hence, there is need for data and resources to be well protected to guarantee its authenticity and to protect systems from network-based attacks. Cryptography and network security have matured, leading to the development of practical, readily available applications to enforce network security. This work covered a review of the concept of randomness with the stringent randomness requirement in data security systems giving particular attention to the Blum-Blum-Shub random number generator.
Performance Analysis of Statistical Time Division Multiplexing Systems
(Leonardo Electronic Journal of Practices and Technologies, 2010-01) Ajiboye, Johnson Adegbenga; Yinusa Ademola Adediran
Multiplexing is a way of accommodating many input sources of a low capacity over a high capacity outgoing channel. Statistical Time Division Multiplexing (STDM) is a technique that allows the number of users to be multiplexed over the channel more than the channel can afford. The STDM normally exploits unused time slots by the non-active users and allocates those slots for the active users. Therefore STDM is appropriate for bursty sources. In this way STDM normally utilizes channel bandwidth better than traditional Time Division Multiplexing (TDM). In this work, the statistical multiplexer is viewed as M/M/1queuing system and the performance is measured by comparing analytical results to simulation results using Matlab. The index used to determine the performance of the statistical multiplexer is the number of packets both in the system and the queue. Comparison of analytical results was also done between M/M/1 and M/M/2 and also between M/M/1 and M/D/1 queue systems. At high utilizations, M/M/2 performs better than M/M/1. M/D/1 also outperforms M/M1.
The Challenges Posed by Information Technology to Secretaries: A Study with Reference to Federal Polytechnic, Bida, Niger State, Nigeria
(The IUP Journal of Information Technology, 2012-12-01) Ajiboye, Johnson Adegbenga; Mary Adebola Ajiboye; Juliet Omozokpia
This study was conducted to identify the challenges of information technologies on secretaries in the Federal Polytechnic Bida, Niger State, Nigeria. The study was embarked upon to emphasize the importance or significance of secretaries as they face the challenges of the information technology in an ICT era. The research was carried out using 50 secretaries. The instrument used in the collection of data was a questionnaire and the data collected was analyzed using the SPSS software. From the analysis of data collected, it was found and concluded that among other things most secretaries lack necessary skills required for ICT in the modern office and most of them with just typing and shorthand skills are on the verge of losing their jobs. Although, it was discovered and concluded that secretaries will not be replaced by computers and that the ones with ICT skills are in high demand and with ample career opportunities in the modern office. It was then recommended that organizations should train and retrain their secretaries to be ICT-compliant and that the curriculum of secretarial study programs should be reviewed and widened to include ICT courses so as to give potential secretaries an ICT background.
Dynamic Spectrum Access (DSA) in Wireless Cognitive Radio Networks (WCRN)
(2013-02-01) Ajiboye, Johnson Adegbenga; Yinusa Ademola Adediran; Mary Adebola Ajiboye
Dynamic Spectrum Access (DSA) is a technology that senses the unused 'free' but allocated portion of the radio frequency spectrum on a non-interfering basis. These unused bands are also known as 'holes' or 'white spaces'. DSA also refers to the time-varying, flexible usage of parts of the radio spectrum under consideration of regulatory and technical restrictions. This type of spectrum access is due to the dynamic behavior that the Secondary User (SU) must employ in order to access the spectrum, while avoiding interfering with a Primary User (PU). Intelligent or Cognitive Radio (CR) is a platform on which the DSA can be implemented. CRs are radio systems that autonomously coordinate the usage of spectrum. They utilize radio spectrum when it is not being used by incumbent (primary) radio systems. Underutilized spectrum can be exploited with the concepts of DSA and CR. This paper reviews the techniques that can be deployed for DSA reliably in a Wireless Cognitive Radio Network (WCRN) and models of network architecture-based DSA in Cognitive Radio Networks (CRN).
Queue Behavior of Statistical Multiplexers
(The IUP Journal of Information Technology, 2013-03-01) Ajiboye, Johnson Adegbenga; Yinusa Ademola Adediran; Mary Adebola Ajiboye
In a statistical multiplexer, packets are assumed to be arriving at the multiplexer with the inter arrival times being Independent and Identically Distributed (IID). The service time is also IID. The inter arrival times are generated from the corresponding probability distribution. When a packet arrives to an empty or idle system, the packet is immediately served; otherwise, it is queued. In this paper, the queue behaviors in the multiplexer's buffer were examined. The results show that the average number of packets in the multiplexer queue increases in an exponential form with increase in utilization; and at high utilization, there is a dramatic increase in the number of packets in the multiplexer queue which may lead to packet loss when there is no sufficient buffering. Comparison of the simulation and analytical results for the mean number of packets in an M/M/I Multiplexer Queue reveals that results are within ±23% for offered load of up to 90%.
Harmonic Reduction Using Fractional Pitch Winding
(3rd Biennial Engineering Conference, Federal University of Technology, Minna. Nigeria, 2013-05-16) Enesi Asizehi Yahaya; Mark Nwohu; Henry Ohize; O. Imoru; Usman N. Galadima
The power source and the nonlinear loads on transmission line are major sources of harmonics and if these harmonics are not controlled, they could lead to heat loss, break down of machines and reducing the efficiency of any machine connected to the supply. The non-sinusoidal currents from the power source increase harmonic contents in the air gap of electrical machines with pole pitch winding which will lead to excessive losses, vibration and noise. This paper presents the use of fractional pitch winding technique for the stator of three phase motor for the purpose of suppressing harmonics. This is investigated between two windings of pole pitch and short-pitch and the results simulated using Emetor Electric Motor software.
Towards independent measurement of End to End Bit Error Rate in GSM network
(IEEE, 2014-09-29) Gbadamosi Safiu Abiodun,; A. M. Aibinu,; E. N Onwuka; O. C. Ugweje
This article introduces the trends of measuring bit error rate of GSM network independently of the service providers using a PC Based Software System. This paper further reveals the role of software defined radio (SDR) in achieving reception and transmission of signals at any carrier frequency using any standard and protocol which can be reprocessed immediately with the aid of the subject software operation of a PC. The results obtained from the reception and transmission of signals can used to estimate the Bit Error of the signal at that frequency. Thus the possibility and mechanisms of independent measurement of End to End Bit Error Rate have been presented in this paper.
Performance Analysis of Sequential Monte Carlo MCMC and PHD Filters on Multi-target Tracking in Video
(IEEE, 2014-10-21) Abdullahi Daniyan
The Bayesian approach to target tracking has proven to be successful in the tracking of multiple targets in various application contexts. This paper applies sequential Monte Carlo (SMC) filtering techniques such as the Markov Chain Monte Carlo particle filter (MCMC PF) and the SMC probability hypothesis density (PHD) filter as suboptimal Bayesian solutions to multi-target tracking (MTT) in video. The MCMC PF by virtue of its information-centric property, can automatically explore the posterior distribution at each sampling step making it possible to track multiple targets. In doing so, it propagates the full multi-target posterior. The SMC PHD filter however propagates only the first order moment of the multi-target posterior density thereby making it computationally less intensive. A comparison of both filters was carried out in tracking multiple human targets in a video scene demonstrating superior performance by the SMC PHD filter in a realistic scenario. The SMC PHD filter was seen to have higher performance than the MCMC PF in terms of the number of particles, the processing speed, and the tracking performance for multiple targets.
Non-intrusive noise reduction in GSM voice signal using non-parametric modeling technique
(International Engineering Conference (IEC), School of Engineering and Engineering Technology, FUT Minna, 2015-06-15) Gbadamosi Safiu Abiodun,; A. M. Aibinu,; O.C.Ugweje,; A. J Onumanyi ,; E. N Onwuka,; M. Aderinola
Noise degrades the quality and intelligibility of speech. It impedes speech clarity, coding, recognition and speaker identification. To mitigate noise effect and improve speech quality, we propose Non-parametric modeling technique along with a Non-intrusive signal denoising system based on short time Fourier transforms. This paper aims to establish only the idea behind our proposed algorithm, however, we present argument to justify that our results will reduce an end to end acoustic background noise; improve quality of speech for both the speaker and the listener and eventually increase throughput. Ultimately, users’ will be able to call and receive calls in a noisy environment while enjoying clarity of voice.
Permanent Split Capacitor (PSC) alternating current induction motor
(Leonardo Electronic Journal of Practices and Technologies, 2015-06-26) Yahaya Asizehi ENESI; Tola J. OMOKHAFE; James G. AMBAFI; Eugene O. AGBACHI
Single phase induction motors are found in various applications in which having correct value of the capacitor connected to the auxiliary winding enables the motor to function efficiently. This research aim is to investigate and obtain the value of the capacitor of a given input parameters of a specified permanent split capacitor (PSC) induction motor using MATLAB, which will in turn provide easy computation of the output parameters for the motor optimum efficiency. Electrical and mechanical characteristics of the PSC induction motor where obtained and analysed of which the study shows that the motor was reliable due to the absence of centrifugal switch. With the aid of MATLAB program the results were easily obtained, PSC induction motor capacitor value at optimum efficiency was also easily determined. The motor proved to have low starting torque, low starting current, higher efficiency, high pull out torque and high power factor. The characteristics of PSC induction motor analysed was limited to where higher starting torque is required only.
Split-phase motor running as capacitor starts motor and as capacitor run motor
(Leonardo Electronic Journal of Practices and Technologies, 2016-06-28) Yahaya Asizehi ENESI; Jacob TSADO; Mark NWOHU; Usman Abraham USMAN; Odu Ayo IMORU
In this paper, the input parameters of a single phase split-phase induction motor is taken to investigate and to study the output performance characteristics of capacitor start and capacitor run induction motor. The value of these input parameters are used in the design characteristics of capacitor run and capacitor start motor with each motor connected to rated or standard capacitor in series with auxiliary winding or starting winding respectively for the normal operational condition. The magnitude of capacitor that will develop maximum torque in capacitor start motor and capacitor run motor are investigated and determined by simulation. Each of these capacitors is connected to the auxiliary winding of split-phase motor thereby transforming it into capacitor start or capacitor run motor. The starting current and starting torque of the split-phase motor (SPM), capacitor run motor (CRM) and capacitor star motor (CSM) are compared for their suitability in their operational performance and applications
Evaluation of Speech Quality Based on QoS Key Performance Index (KPI): A Survey.
(International Engineering Conference (IEC), 2017-06-13) Gbadamosi Safiu Abiodun,; Maliki D.
The utmost contest between cellular operators have left the customers highly selective with the quality of speech based on the quality of service (QoS) experienced. In order to quantitatively and qualify the network performance based on speech quality, different key performance indicators (KPI) used, are classified to aid data collection independently of the cellular providers. In this paper, a survey of different techniques of KPI data collection methods that are used to reduce impairment as its affect speech are discussed and classified according to their operational mode. It provides a detailed report about the perceptuality of speech quality and its statistical expectation of the network. Each of these techniques has its advantages and disadvantages as applied to underscore the network performance from a user’s point of view. These techniques evaluate degradation caused by various impairments in cellular networks. It is our hope that, if user get hold of these applications, it will go a long way to keep cellular operators on their toes.
Data association using game theory for multi-target tracking in passive bistatic radar
(IEEE, 2017-06-20) Yu Gong; Abdullahi Daniyan; Abdulrazaq Aldowesh; Sangarapillai Lambotharan
We investigate a game theoretic data association technique for multi-target tracking (MTT) with varying number of targets in a real passive bi-static radar (PBR) environment. The radar measurements were obtained through a PBR developed using National Instrument (NI) Universal Software Radio Peripheral (USRP). We considered the problem of associating target state-estimates-to-tracks for varying number of targets. We use the sequential Monte Carlo probability hypothesis density (SMC-PHD) filter to perform the multi-target tracking in order to obtain the target state estimates and model the interaction between target tracks as a game. Experimental results using this real radar data demonstrate effectiveness of the game theoretic data association for multiple target tracking.
An improved resampling approach for particle filters in tracking
(IEEE, 2017-11-06) Yu Gong; Sangarapillai Lambotharan; Abdullahi Daniyan
Resampling is an essential step in particle filtering (PF) methods in order to avoid degeneracy. Systematic resampling is one of a number of resampling techniques commonly used due to some of its desirable properties such as ease of implementation and low computational complexity. However, it has a tendency of resampling very low weight particles especially when a large number of resampled particles are required which may affect state estimation. In this paper, we propose an improved version of the systematic resampling technique which addresses this problem and demonstrate performance improvement.
MANAGEMENT OF ELECTRIC POWER IN NIGERIA
(International Conference on Information Systems and Management Science, 2018) Ajiboye, Johnson Adegbenga; Mary Adebola Ajiboye; Misra Sanjay
Development of Non-Parametric Noise Reduction Algorithm for GSM Voice Signal
(ABUAD Journal of Engineering Research and Development (AJERD), 2018-12-31) Gbadamosi, Safiu Abiodun,; AIBINU, Musa Abiodun ,; ONUMANYI, Adeiza James
Speech enhancement in Global System for Mobile communication (GSM) is an area of engineering that study different kinds of techniques used in enhancing GSM voice signals. The presence of noise in GSM degrades the quality and intelligible of speech which impedes speaker identification and sound clarity. In this paper, non-parametric noise reduction algorithm which incorporates an adaptive threshold technique is proposed to estimate the adaptive threshold value as a function of first and second order statistics of the voice signal. It uses the cumulative value of minimum mean and maximum standard deviation value and minimum (mean and standard deviation) to minimize the effect of impairments introduced by background noise and GSM channels. The algorithm was implemented in MATLAB environment. The results obtained indicate correlation coefficients of 53.93% and 45.52% for maximum and minimum threshold value at 2.95 standard deviation of noise and 77.93% and 75.83% for maximum and minimum threshold value at 0.25 standard deviation of noise, respectively. Evaluation of the proposed algorithm was performed on real noisy voice signal and a correlation of 92.15% and 89.24% was achieved for both maximum and minimum threshold values with mean square error of 0.0011% and 0.00033%, respectively. These results have proven the efficiency of the proposed algorithm. The threshold values have satisfied perfect noise reduction when the mean and standard deviation values are selected properly
Electromagnetic field analysis of a single-phase induction motor based on finite element method
(3rd International Engineering Conference (IEC 2019) Federal University of Technology, Minna, Nigeria, 2019-05-06) Omokhafe J. Tola; Edwin A. Umoh; Enesi A. Yahaya; Chika Idoko; Ayo Imoru
Electric motors are critical components of Electric drives systems, and their performance efficiency has consequences for the fidelity of electric drives and control. This paper presents an analysis of the electromagnetic field of a single-phase induction motor based on two-dimensional finite element method. The developed model of the machine was used to study its performance characteristics at different speed conditions, a view to affirm the accuracy of the specifications of the motor. The motor losses were analyzed and the transient results revealed the losses and a start-up time of 0.07 second with low pulsation at steady state. This implies the specifications are accurate. Therefore, the developed model has possibilities of applications in power system generating systems and industrial plants.
Promoting an IoT-based waste-bin management system in higher institution
(Journal of Science, Technology, Mathematics and Education (JOSTMED), 2019-12-13) Gbadamosi Safiu Abiodun; Galadima Nuhu Usman
The accumulation of waste around faculty and hostels in higher institutions has become a great sense of concern to both staff and students. Often time the scene of the dumb sites is characterized by unpleasant smell and germs that can be harmful to the health status of both staff and students. To maintain the waste collection and proper waste disposal, we propose an IoT-based waste-bin management system. The IoT-based waste-bin management system employed the use of cloud server (Thingspeak) capable of computing, analysing and presenting a graphical representation of waste with the aid of an ultrasonic sensor through the microcontroller unit embedded with WiFi module. The ultrasonic sensor monitors the waste in respect to the time difference between the emitted and receipted wave of the sensor at a frequency of 40 kHz from a distance of 2 cm to 400 cm. The microcontroller samples, digitized and processed the sensor data before being sent over the network to the cloud server. The result obtained is a graphical representation of the status of the waste viewed from both the liquid crystal display (LCD) and the web interface. The graph varies from 25% to approximately 75% filled value of the waste-bin. The system can be used for proper monitoring and for future decisive actions on amount of waste generated. The device is easy to implement due to its cost-effectiveness.
Building Upon NB-IoT Networks: A Roadmap Towards 5G New Radio Networks
(IEEE, 2020-10-13) Gbadamosi, Safiu Abiodun,; Hancke, Petrus Gerhard; Abu-Mahfouz Adnan M.
Narrowband Internet of Things (NB-IoT) is a type of low-power wide-area (LPWA) technology standardized by the 3rd-Generation Partnership Project (3GPP) and based on long-term evolution (LTE) functionalities. NB-IoT has attracted significant interest from the research community due to its support for massive machine-type communication (mMTC) and various IoT use cases that have stringent specifications in terms of connectivity, energy efficiency, reachability, reliability, and latency. However, as the capacity requirements for different IoT use cases continue to grow, the various functionalities of the LTE evolved packet core (EPC) system may become overladen and inevitably suboptimal. Several research efforts are ongoing to meet these challenges; consequently, we present an overview of these efforts, mainly focusing on the Open System Interconnection (OSI) layer of the NB-IoT framework. We present an optimized architecture of the LTE EPC functionalities, as well as further discussion about the 3GPP NB-IoT standardization and its releases. Furthermore, the possible 5G architectural design for NB-IoT integration, the enabling technologies required for 5G NB-IoT, the 5G NR coexistence with NB-IoT, and the potential architectural deployment schemes of NB-IoT with cellular networks are introduced. In this article, a description of cloud-assisted relay with backscatter communication, a comprehensive review of the technical performance properties and channel communication characteristics from the perspective of the physical (PHY) and medium-access control (MAC) layer of NB-IoT, with a focus on 5G, are presented. The different limitations associated with simulating these systems are also discussed. The enabling market for NB-IoT, the benefits for a few use cases, and possible critical challenges related to their deployment are also included. Finally, present challenges and open research directions on the PHY and MAC properties, as well as the strengths, weaknesses, opportunities, and threats (SWOT) analysis of NB-IoT, are presented to foster the prospective research activities
Pulse Width Modulation Analysis of Five-Level Inverter- Fed Permanent Magnet Synchronous Motors for Electric Vehicle Applications
(International Journal of Robotics and Control Systems, 2021-11-21) Omokhafe J. Tola; Edwin A. Umoh; Edwin A. Umoh
n recent times, intense research has been focused on the performance enhancement of permanent magnet synchronous motors (PMSM) for electric vehicle (EV) applications to reduce their torque and current ripples. Permanent magnet synchronous motors are widely used in electric vehicle systems due to their high efficiency and high torque density. To have a good dynamic and transient response, an appropriate inverter topology is required. In this paper, a five-level inverter fed PMSM for electric vehicle applications, realized via co-simulation in an electromagnetic suite environment with a reduced stator winding current of PMSM via the use of in-phase disposition (PD) pulse width modulation (PWM) techniques as the control strategy is presented. The proposed topology minimizes the total harmonic distortion (THD) in the inverter circuit and the motor fed and also improves the torque ripples and the steady-state flux when compared to conventional PWM techniques. A good dynamic response was achieved with less than 10A stator winding current, zero percent overshoot, and 0.02 second settling time synchronization. Thus, the stator currents are relatively low when compared to the conventional PWM. This topology contribution to the open problem of evolving strategies that can enhance the performance of electric drive systems used in unmanned aerial vehicles (UAV), mechatronics, and robotic systems