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4.3 Game-theoretic solutions for resource allocation and tracking
(UDRC, 2018-10-10) Anastasios Deligiannis, Abdullahi Daniyan, Gaia Rossetti, Sangarapillai Lambotharan, Jordi Barr
A 3-Person Non-Zero-Sum Game for Sachet Water Companies
(Asian Research Journal of Mathematics, 2022-06-24) Nyor, N.; Muazu, M. I.; Somma Samuel Abu
The business of Sachet water (popularly called pure water) in Nigeria is often competitive due to the high demand for Sachet water by the populace. This is so because sachet water is the most affordable form of pure drinking water in Nigeria. As such, Sachet Water Firms that want to succeed in an ever increasing competitive market need to have the knowledge of Game Theory to identify which strategy will yield better profit independent of the strategy adopted by other competitors. This paper is aimed to investigate and determine the equilibrium point for three Sachet Water Firms using the Nash Equilibrium Method as it provides a systematic approach for deciding the best strategy in competitive situation. The result showed two Nash Equilibriums (promo, promo) and (stay-put, stay-put) with their respective payoffs of (82; 82; 82) and (147; 147; 147).
A 3-step block hybrid backward differentiation formulae (bhbdf) for the solution of general second order ordinary differential equation
(New Trends in Mathematical Sciences, 2021-07-12) Hussaini Alhassan; Muhammad Raihanatu
In this paper, the block hybrid Backward Differentiation formulae (BHBDF) for the step number k=3 is developed using power series as basis function for the solution of general second order ordinary differential equation. The idea of interpolation and collocation of the power series at some selected grid and off- grid points gave rise to continuous schemes which were further evaluated at those points to produce discrete schemes combined together to form block methods. Numerical problems were solved with the proposed methods and were found to perform effectively.
A 4-STAGE RUNGE-KUTTA TYPE METHOD FOR SOLUTION OF STIFF ORDINARY DIFFERENTIAL EQUATIONS
(Pan-American Journal of Mathematics, 2024) RAIHANATU MUHAMMAD; ABDULMALIK OYEDEJI
In this paper, a 2 step implicit block hybrid linear multistep method was reformulated into a 4-stage block hybrid Runge-Kutta Type Method via the butcher analysis. The method can be used to solve first order stiff ordinary differential equations. A numerical example solved with the proposed method showed a better result in comparison with an existing method
A Backward Diffrention Formula For Third-Order Inttial or Boundary Values Problems Using Collocation Method
(Islamic Azad University,Rasht ', Iran, 2021-09-19) AbdGafar Tunde Tiamiyu; Abosede Temilade Cole; Khadeejah James Audu
We propose a new self-starting sixth-order hybrid block linear multistep method using backward differentiation formula for direct solution of third-order differential equations with either initial conditions or boundary conditions. The method used collocation and interpolation techniques with three off-step points and five-step points, choosing power series as the basis function. The convergence of the method is established, and three numerical experiments of initial and boundary value problems are used to demonstrate the efficiency of the proposed method. The numerical results in Tables and Figures show the efficiency of the method. Furthermore, the numerical method outperformed the results from existing literature in terms of accuracy as evident in the results of absolute errors produced
A COMPARATIVE ANALYSIS OF GRILLAGE METHOD AND BEAM LINE ANALYSIS OF A REINFORCED CONCRETE WAFFLE BRIDGE DECK
(2023) Adamu, H. N.; Abbas B.A.; Abubakar, M.; Yusuf, A.; Kolo, D.N.; Shehu, M.
The analysis of a reinforced concrete waffle bridge deck using Chanchaga Bridge as a case study was carried out with the aid of computer programme written in MATLAB. The bridge deck which is a beam bridge was idealized to be a waffle slab. A mathematical model of the bridge was developed using the method of grillages because very complex shapes of problem domain with prescribed conditions can be handled easily using the method. The bridge deck was modelled as interconnection of grid elements. The analysis was carried out using direct stiffness matrix method. The nodal displacements and the resulting static internal forces; shear forces, bending moments and twisting moments of each grid element were determined using the matrix. The results obtained using the method of grillages were then compared with beam line analysis and the former method gave a 10% decrease in forces which will result in the reduction of overall design and materials by 10%.
A Comparison of Code Maintainability in Agile Environment
(IUP Journal of Information Technology, 2016-06-01) Mary Adebola Ajiboye; Matthew Sunday Abolarin; Ajiboye, Johnson Adegbenga
The demand for quick delivery of quality software is becoming high among software clients due to the fast changing technology in the dynamic world. Agile software development meets this demand and has gained appropriate and wide acceptance among software practitioners. However, the quality of such software is greatly impacted by its maintainability. Unfortunately, existing works focused only on the flexibility aspect of maintainability without paying attention to timely delivery. In this work, maintainability as a function of time to correct codes was examined among various categories of software developers. Deliberate errors, ranging from two to nine, were introduced into sets of agile codes written in python programming language and given to 100 programmers, each in the groups of individual junior, individual expert, random, expert pairs, junior pairs and junior expert pairs. The results revealed that random pair programmers spent the highest time of 21.88 min/bug on the average, while individual experts spent the least time of 16.26 min/bug.
A delay-aware spectrum handoff scheme for prioritized time-critical industrial applications with channel selection strategy
(Elsevier, Computer Communications, 2019-05-11) Oyewobi S. Stephen; Gerhard P. Hancke; Adnan M. Abu-Mahfouz; Adeiza Onumanyi
Cognitive radio has emerged as an enabling technology in the realization of a spectrum-efficient and delaysensitive industrial wireless communication where nodes are capable of responding in real-time. However, particularly for time-critical industrial applications, because of the link-varying channel capacity, the random arrival of a primary user (PU), and the significant delay caused by spectrum handoff (SH), it is challenging to realize a seamless real-time response which results in a quality of service (QoS) degradation. Therefore, the objectives of this paper is to increase spectrum utilization efficiency by allocating channel based on the priority of a user QoS requirements, to reduce SH delay, to minimize latency by preventing avoidable SHs, and to provide real-time response. To achieve an effective spectrum utilization, we proposed an integrated preemptive/non-preemptive priority scheme to allocate channels according to the priority of user QoS requirements. On the other hand, to avoid significant SH delays and substantial latency resulting from random PU arrival, a unified spectrum sensing technique was developed by integrating proactive sensing and the likelihood estimation technique to differentiate between a hidden and a co-existence PU, and to estimate the mean value of the busy and the idle periods of a channel respectively. Similarly, to prevent poor quality channel selection, a channel selection technique that jointly combines a reward system that uses metrics, e.g. interference range, and availability of a common channel to ranks a set of potential target channels, and a cost function that optimizes the probability of selecting the channel with the best characteristics as candidate channels for opportunistic transmission and for handoffs was developed. The simulation results show a significant performance gain of the delay-PritSHS in terms of number of SHs, Latency, as well as throughput for time-critical industrial applications in comparison to other schemes.
A Fundamental Review of Trends in Perovskite Solar Cells Based on Introduction of Buffer Layers to Enhance Stability
(JOURNAL OF SCIENCE TECHNOLOGY AND EDUCATION, 2020) J. Y. Jiya; J. S. Enaburekhan; M. T. Jimoh; E. C. Egwim
Perovskite solar cells (PSCs), as photo-electric conversion devices, exhibit adequate power conversion efficiency (PCE) and low processing cost and have thus become one of the most promising devices to replace conventional silicon-based solar cells thereby addressing current prevailing energy issues. Despite rapid progress in the perovskite solar cell efficiency, there have been concerns about issues which could affect the measurement accuracy and/or practical applications of these devices, amongst which are stability, scaling up (large area devices), and possible environmental effects related to the use of lead-based active material. Current PSCs use nonbiodegradable petroleum-based polymer substrates, discarding of which will aggravate environmental pollution. In this study, a review of the fundamentals and progress in the perovskite solar cell (PSC) is discussed. The processing cost of metal electrode deposition in PSC is very costly, hence, the replacement of the metal electrode by some other low-cost counter electrode is discussed.
A Hybrid Web Caching Design Model for Internet-Content Delivery
(Covenant Journal, 2016) Alfa, A. A., Ogwueleka, F. N., Dogo, E. M., & Sanjay, M.
The need for online contents (or resources) to be shared and distributed in a large and sophisticated networks of users, geographical dispersed location of servers and their clients, time taken to fulfil clients requests pose major challenge. Therefore the choice of suitable architecture for Internet-based content delivery (ICD) technologies readily comes to mind. To achieve this, Akamai and Gnutella Web technologies are extensively reviewed to identify their strengths and weakness because of their popularity across the world for delivering contents. This new design for Internet-based content distribution is called AkaGnu because of the extra layer (Gnutella network) inserted into Akamai architecture, which provides greater Internet edge over each technology deployed independently. The paper presents a new ICD technology that performs better than Akamaisystem as a result of new features and behaviours introduced that reduce network traffic, more clients Internet connectivity, increase file sharing, improved speed of contents deliveries, and enhanced network security.
A Mathematical Model of a Yellow Fever Dynamics with Vaccination
(Journal of the Nigerian Association of Mathematical Physics, 2015-11) F. A. Oguntolu; N. I. Akinwande; S. A. Somma; F. Y. Eguda; T. T. Ashezua
In this paper, a mathematical model describing the dynamics of yellow fever epidemics, which involves the interactions of two principal communities of Hosts (Humans) and vectors (mosquitoes) is considered. The existence and uniqueness of solutions of the model were examined by actual solution. We conduct local stability analysis for the model. The results show that it is stable under certain conditions. The system of equations describing the phenomenon was solved analytically using parameter-expanding method coupled with direct integration. The results are presented graphically and discussed. It is discovered that improvement in Vaccination strategies will eradicate the epidemics.
A protocol for setting dose reference level for medical radiography in Nigeria: A Review
(BAYERO UNIVERSITY, KANO, NIGERIA, 2010-02-10) OLARINOYE, OYELEKE; SHARIFAT I
Patients’ dose audit reports in some Nigerian hospitals had shown large inter- and intra-hospital variations for the same radiological examinations. They have thus presented the need, to have a national standard for radiological diagnostic procedures and set dose limits for individual x-ray examination centers in Nigeria. These will go a long way in reducing inter- and intra-hospital dose range factors, thus reducing doses to as low as reasonably achievable and consistent with clinical objectives of the examinations. In establishing a national dose limit for medical radiological examinations, there is a need to have a national dose survey. This paper suggests a Reasonable and easy procedure for achieving a national radiological dose survey. Due to its simplicity of measurement, the use of entrance surface dose as the dose parameter to be used for setting the dose limit as recommended by the European Union and the International Atomic Energy Agency (IAEA) is also suggested. ESD can be measured directly through the use of solid state detectors, or indirectly by measuring free air exposure which can later be converted to ESD using standard formula. The methods of measuring the entrance surface dose and how to derive the dose limit from them are also highlighted.
A review of coating tin oxide electron transport layer for optimizing the performance of perovskite solar cells
(Chemistry of Inorganic Materials Volume 6, August 2025, 100100, 2025-04-10) YUSUF Abubakar Sadiq; Ahmad Alhaji Abubakar; Isah Kimpa Mohammed; Umaru Ahmadu; Kasim Uthman Isah
Perovskite solar cells (PSCs) have recently emerged as a transformative technology in the photovoltaic sector, drawing considerable attention due to their rapid advancements in power conversion efficiency (PCE), which now exceeds 26.7 %. This efficiency level places them in direct competition with conventional silicon-based solar cells. A key element in ensuring the high performance of PSCs is the charge transport layer (CTL), particularly the electron transport layer (ETL). The ETL plays a crucial role by efficiently collecting photo-generated electrons from the perovskite layer and transferring them to the transparent conductive oxide electrode. Among the ma- terials used for ETLs, tin oxide (SnO 2) stands out for its wide band gap, excellent optical transparency, superior carrier mobility, and remarkable chemical stability. Additionally, SnO2 can be deposited at low temperatures, making it ideal for mass production and adaptable for applications such as flexible devices. Despite its inherent advantages, the overall performance and quality of the ETL, and thus the device itself, are heavily influenced by the fabrication process. This study reviews recent approaches to fabricating SnO 2 ETLs in PSCs, with a focus on optimizing efficiency and long-term stability
A Sensor-Based Data Acquisition System for Soil Parameters to Determine Suitable Crops
(2023) Abisoye, B. O.; Dogo, E. M.; Umar, B. U.; Mamman, I. Z.
Soil parameters monitoring is significant in sustainable crop and food production. The standard strategy of soil parameters monitoring in developing and underdeveloped nations uses manual labor, resulting in wrong decisions in soil management. Inaccurate measurements due to sensor miscalibration or low sensor quality can lead to incorrect soil management decisions and negatively impact crop yield and environmental sustainability. Due to the mentioned challenges, this work aims to develop a Sensor-based Data Acquisition System for Soil Parameters that will enable users to observe various soil parameters like temperature, humidity, water level and soil pH. The system was developed using the combination of hardware and software components. The hardware component comprises of sensory and processing parts. The study calibrates sensors using known pH, moisture, and temperature values for specific crops to grow in Nigeria. The system will aid farmers in determining suitable crops for their farmland and increasing crop yield. The system collects data through a network of sensors installed in the soil and wirelessly transmits the data to a cloud-based server. The collected data is then analyzed and visualized in through a web-based dashboard, providing farmers with information about the state of their soil. The performance evaluation of the system was carried out using response time and accuracy. The average response time of the system was 4 seconds, and the percentage error for temperature and humidity readings when compared to weather forecast readings were 8.20% and 5.08%, respectively. The results show that the proposed system can provide accurate and reliable measurements of soil parameters and can be easily deployed and operated by small-scale farmers. Using this system can result in improved crop yields, reduced wastage, and better overall efficiency in agricultural operations.
A Sixth Order Implicit Hybrid Backward Differentiation Formulae (HBDF) for Block Solution of Ordinary Differential Equations
(American Journal of Mathematics and Statistics, 2012) Muhammad R; Yahaya.Y.A
The Hybrid Backward Differentiation Formula (HBDF) for case K=5 was reformulated into continuous form using the idea of multistep collocation. Multistep Collocation is a continuous finite difference (CFD) approximation method by the idea of interpolation and collocation. The hybrid 5-step Backward Differentiation Formula (BDF) and additional methods of order (6,6,6,6,6,)𝑇𝑇 were obtained from the same continuous scheme and assembled into a block matrix equation which was applied to provide the solutions of IVPs over non-overlapping intervals.The continous form was im-mediately employed as block methods for direct solution of Ordinary Differential Equation (𝑦𝑦′=𝑓𝑓(𝑥𝑥,𝑦𝑦)). Some benefits of this study are, the proposed block methods will be self starting and does not call for special predictor to estimate 𝑦𝑦’ in the integrators and all the discrete methods obtained will be evaluated from a single continuous formula and its derivatives at various grids and off grid points. These study results help to speed up computation, also the requirement of a starting value and the overlap of solution model which are normally associated with conventional Linear Multistep Methods were elimi-nated by this approach. In conclusion, a convergence analysis of the derived hybrid schemes to establish their effectiveness and reliability was presented. Numerical example carried out on stiff problem further substantiates their performance.
A Spectrum Management Strategy for Visible Light Communications Using an Adaptive Threshold Approach
(SATNAC 2021 conference, 2021-11-24) Oyewobi S. Stephen; K. Djouani; A. Kurien
The accessibility of network resources is the primary criteria used to perform handover in existing handover strategies in communication systems. Moreover, the access technique approach implemented in visible light communications (VLC) which utilizes the availability of the channel as the sole criteria for handover instead of the capacity of the channel to support QoE of nodes leads to frequent handovers and poor QoE performance. In this work, the use of adaptive threshold-fixing is proposed to dynamically fix the trigger threshold for handover to match the minimum QoE constraints of the VLC node. Therefore, a node will remain in its current channel as long as the minimum QoE requirements are supported by the present channel. Hence, nodes will only handover if the current channel does not support the least QoE constraints of specific node applications and new channels with better QoE are available. To achieve this, the proposed algorithm dynamically adjusts the handover triggering threshold based on link information extracted from channel at discrete time to meet the minimum QoE constraints of node applications instead of switching to a new available channel. The proposed alogorithm is implemented using Monte Carlo simulations of different VLC scenarios and is compared with a reactive spectrum handoff strategy. Simulations results of the proposed strategies demonstrate a significant reduction of spectrum handoffs while maintaining better throughput for node applications.
A THIRD REFINEMENT OF JACOBI METHOD FOR SOLUTIONS TO SYSTEM OF LINEAR EQUATIONS
(Federal University, Dutsin Ma, Nigeria, 2023-10-15) Khadeejah James Audu; James Nkereuwem Essien; Abraham Baba Zhiri; Aliyu Rasheed Taiwo
Solving linear systems of equations stands as one of the fundamental challenges in linear algebra, given their prevalence across various fields. The demand for an efficient and rapid method capable of addressing diverse linear systems remains evident. In scenarios involving large and sparse systems, iterative techniques come into play to deliver solutions. This research paper contributes by introducing a refinement to the existing Jacobi method, referred to as the "Third Refinement of Jacobi Method." This novel iterative approach exhibits its validity when applied to coefficient matrices exhibiting characteristics such as symmetry, positive definiteness, strict diagonal dominance, and 𝑀 -matrix properties. Importantly, the proposed method significantly reduces the spectral radius, thereby curtailing the number of iterations and substantially enhancing the rate of convergence. Numerical experiments were conducted to assess its performance against the original Jacobi method, the second refinement of Jacobi, and the Gauss-Seidel method. The outcomes underscore the "Third Refinement of Jacobi" method's potential to enhance the efficiency of linear system solving, thereby making it a valuable addition to the toolkit of numerical methodologies in scientific and engineering domains.
Abandoned Building Projects: Source of Environmental Degradation
(Journal of Environmental Research and Policies, 2008) Lawal, Lateef Ademola; Goshi, Sarah K.
Buildings irrespective of size, form and function have an effect on observers and also on the physical environment. This effect could either be positive or negative. The issue of abandoned buildings in Nigeria is not a new phenomenon. Depending on how one looks at it, it represents a failure in that a specific goal has not been achieved. This paper examines abandoned buildings as sources of environmental degradation. It highlights factors that responsible for abandoned buildings as largely man-made, such as insufficient budget provision for the project and litigation among others. It presents findings on some of the abandoned buildings in Minna, Niger State, Nigeria. The paper recommends reclaiming of titles by the government on the one hand, and periodic evaluation of distressed properties with a view to determining and preventing abandonment of buildings on the other.
Academic Discipline Differences and how it affects the Information Seeking Behavior of Information Users
(Sri Lanka Technological Campus in Collaboration with the department of Library and Information SCience, University of Kelaniya SRi Lanka, the department of library and information science universty of Kerala India, and the National science library and resource centre (NSLRC) of the National Science Foundation (NSF) SRi Lanka, 2021-08-23) Goshie, Rhoda Wusa
This paper is on the academic discipline differences and how it affects the information seeking behavior of information users. It gave the concept of an academic discipline or field of study as a branch of knowledge, taught and researched as part of higher education by the university faculties and learned societies to which they belong and the academic journals in which they publish research. Information- seeking behavior on the other hand is a more specific concept of information behavior. It specifically focuses on searching, finding, and retrieving information. The paper explained the biglan classification scheme. It also highlighted the problem statement such as lack of reading material on this subject on graduate students, especially in Africa. The paper went further to review the researches and related studies on the subject matter and also gave recommendation and conclusions which all emanates from the research
Adaptive Interference Avoidance and Mode Selection Scheme for D2D-Enabled Small Cells in 5G-IIoT Networks
(IEEE, 2024-02-10) Gbadamosi, Safiu Abiodun,; Hancke, Gerhard Petrus; Abu-Mahfouz Adnan M.
Small cell (SC) and device-to-device (D2D) communications can fulfill high-speed wireless communication in indoor industrial Internet-of-Things (IIoT) services and cell-edge devices. However, controlling interference is crucial for optimizing resource sharing (RS). To address this, we present an adaptive interference avoidance and mode selection (MS) framework that incorporates MS, channel gain factor (CGF), and power-allocation (PA) techniques to reduce reuse interference and increase the data rate of IIoT applications for 5G D2D-enabled SC networks. Our proposed approach employs a two-phase RS algorithm that minimizes the system’s computational complexity while maximizing the network sum rate. First, we adaptively determine the D2D user mode for each cell based on the D2D pair channel gain ratios of the cellular and reuse mode. We compute the CGF for each cell with a D2D pair in reuse mode (RM) to select the reuse partner. Then we determine the optimal distributed power for the D2D users and IoTuser equipment using the Lagrangian dual decomposition method to maximize the network sum rate while limiting the interference power. The simulation results indicate that our proposed approach can maximize system throughput and signal-to-interference plus noise ratio, reducing signaling overhead compared to other algorithms