1116 research outputs found
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One-step fourth derivative block integrator for the numerical solution of singularly perturbed third-order boundary value problems
No full textThird-order singularly perturbed problems are common models that are prevalent in applied mathematics and engineering. They model physical phenomenon in fluid dynamics, optimal control, reaction-diffusion processes and many other fields. A one-step fourth derivative block integrator is derived in this work to numerically solve general singularly perturbed third-order problems in ordinary differential equations with prescribed initial or boundary conditions. The derivation of this block of integrators was achieved via the collocation technique where a shifted Chebyshev polynomial of the first kind is used as the trial solution. The characteristics of the method are shown and the numerical examples shows an excellent performance in terms of accuracy of this block method as compared to existing methods already in literature
Effects of Relaxation Times from the Bloch Equations on Age Related Changes in White and Grey Matter
No full textThis research work presented the analytical method of using T1 and T2 relaxation rates of white matter and grey matter to distinguish the passage of time on human organs. A time dependent model equation evolved from the Bloch Nuclear Magnetic Resonance equation was solved under the influence of the radio frequency magnetic field [rfB1(x, t) ̸= 0] and in the absence of radio frequency magnetic field [rfB1(x, t) = 0]. The general solution was considered in three cases. Analysis of the solutions obtained revealed that the rate of decrease of the white matter was faster than that of the grey matter. Between 100 and 400 seconds the difference is more noticeable
Stock Option Price Computation under Economic Recession-Induced Stochastic Volatility Heston Model
No full textWe present a model for an option pricing with economic recession-induced stochastic volatility in a univariate Heston setting. The recession-induced volatility concept of Bankole and Ugbebor is extended to the Heston model to account for uncertainty effect of recession on option returns on an underlying stock asset in a recessed economy. The model formulated is subjectto two economic states which allows regime switching based on the economic state under consideration. The characteristic function for the model is derived and subjected to fast Fourier transform method of Carr and Madan for option price computation. The numerical integration approximations based on Trapezoidal rule and Simpson’s rule is applied and simulation of themodel is carried out to obtain European-type call option prices. The option prices obtained following the assumptions and modifications incorporated, shows significant improvement on the existing Heston model especially with the economic recession parameters inclusion
Common Fixed Point Results for Asymptotic Quasi-Contraction Mappings in Quasi-Metric Spaces
No full textIn this article, two new classes of pairs {T, f} consisting of an asymptotic quasi-contraction T with respect to a map f are introduced. The existence and uniqueness of the common fixed point of such pairs {T, f} is then established in the context of a quasi-metric space X, when T and f are weakly compatible. The theorems obtained rely on some conditions on the orbit OT ,f (x, ∞) of T at points x ∈ X with respect to f, and are in fact, improvements of previously known results in the literature of metric-types. An example is given to validate the results obtained
Diphtheria Disease Transmission Dynamics In Low Vaccine Coverage Setting
No full textDiphtheria is a severely infectious respiratory disease which transmits through droplets and preventable by periodic vaccine programs. In this paper, A six (6) Compartmental model (S, E, IA, IS, Q, R) is presented to undersee the behaviour of diphtheria disease transmission within a group of people with low or zero vaccine coverage and immunity gaps. This research explores epidemiology and mathematically well-posed model. The reproduction number was analysed using the Next Generation Matrix, we underscored that a single infected individual can trigger an outbreak, and further investigation indicates that the disease will subside if the reproduction number (R0) is less than 1, and vice versa if R0 exceeds 1. The model captures disease mitigating strategies like maternally derived immunity, vaccination, Quarantine, and asymptomatic carriers to assess how contagious the disease is and what interventions might be most effective. To validate theoretical model predictions, we conducted numerical simulations using MATLAB 2021a software. Relevant and informative model Simulations are displayed in the full text
Variable exponent Picone identity and p(x) sub-Laplacian first eigenvalue for general vector fields
No full textPicone identity is a powerful tool for proving qualitative properties of differential operators with ubiquitous applications in the analysis of partial differential equations, so generalizing it for different types of differential equations has become a desired venture. p(x)-Laplacian is a non-homogeneous quasilinear partial differential operator arising from various mathematical model with non-standard growth. However, in this paper, we establish a new generalized nonlinear variable exponent Picone identities for p(x)-sub-Laplacian. As applications we prove uniqueness, simplicity, monotonicity and isolatedness of the first nontrivial Dirichlet eigenvalue of p(x)-sub-Laplacian with respect to the general vector fields. Further applications yield Hardy type inequalities and Caccioppoli estimates with variable exponents
Factors Influencing Adoption of Building Management System in Commercial Buildings in Lagos State, Nigeria
No full textAgainst the backdrop of increasing technological innovation and rising demand for sustainability in the built environment, there is a clear need to explore the application of Building Management System BMS in the Nigerian real estate sector. Accordingly, this paper examined the concept of adopting Building Management System (BMS) in commercial buildings in Lagos State, Nigeria with a view to assessing performance on SDG 11 (Sustainable cities and communities) where issues around resilience in buildings is hosted. The study administered one hundred and eighteen questionnaires to facility managers of commercial buildings that have adopted BMS in five local government areas in Lagos State. The data were processed using the principal component (factor) analysis and regression correlation analysis tool. It was found that a range of social and cost factors influenced the adoption of BMS in the study area. Specifically, level of occupant comfort and ease of use of the system were the most significant factor while implementation cost and extent of energy savings also strongly influenced BMS adoption in the study area. The chapter offers suggestions on strategies to improve adoption of BMS and recommends awareness campaigns and the introduction of promotional incentives to the public on BMS
Urban Fragility and the Aspiration for a Resilient City: Some Reflections on Jos Metropolis, Nigeria
No full textUrban fragility is a phenomenon that is conditioned by an accumulation of risks factors leading to crises, disruptions and destructions of varying scales in urban areas. Urban resilience seeks to mitigate fragility or counter its effects. It is on this theoretical footing that this empirical study is conducted in Jos metropolis in north central Nigeria, a location that has over the years accumulated devastating risks factors in spite of efforts to achieve resilience. Accordingly, the study undertakes an analysis of the scale of urban fragility along with the initiatives taken to improve resilience and mitigate the effects of fragilities in Jos metropolis. To this end, a wide range of secondary source material pertaining to nature and sources of fragilities and their impacts on humans, properties and supply of services was collected and combined with observations and lived experience for critical analysis. The analysis confirms that locational exposure of Jos to natural disasters in form of rainstorms and flash floods, as well as the absence of mitigation strategies, was responsible for fragilities leading to deaths, loss of property and disruptions of the supply of utility services on a seasonal basis. Other fragilities resulting from poor local governance, environmental degradation and overstretching of resources also produce environmental and socioeconomic impacts. It is concluded that human activities and the absence of adequate regulations at the city level expose the urban population to hazards. Further analysis suggests that resilient initiatives were tailored at improving urban governance, the institutional framework and the legal as well as regulatory mechanisms. While these efforts quite aligned with resilient intentions, they were, however, affected by inconsistencies and delayed implementation. Appropriate recommendations for upturning this situation in Jos metropolis are offered in the study
Gender Discrimination in the Rental Housing Market: Conceptual Ideas and Empirical Evidence from Lagos, Nigeria
No full textThis study examines the complex issues surrounding gender discrimination in the rental housing market in Lagos, Nigeria. It investigates the reasons for gender preferences alongside the immediate reactions and responses of female tenants who experienced rental housing discrimination, which frequently manifests as higher rent demands, unfavourable lease terms and outright denial of housing, among others. The mixed methods study used instruments that were tested for reliability and validity, with copies of the questionnaire being served to real-estate practitioners and interviews conducted with female tenants to develop evidence-based policy recommendations for addressing gender discrimination and promoting equitable access to rental housing in Lagos State. Thus, the study makes an important contribution to the discourse of gender discrimination. Given the cultural roots of such discrimination, the study suggests the need for an awareness campaign targeting diverse actors within the housing market. The study noted that the Nigerian government has enacted laws to protect women's rights in housing, implementation remains a challenge. Therefore, promoting gender equality in housing requires the concerted efforts of government and the collective resistance of civil-society organisations and the private sector
Robotic Technologies and Automation in Construction: A Systematic Review
No full textThe global construction industry is experiencing a high rate of disruption arising from the deployment of emerging robotic technologies and process automation. This study investigates research trends in robotic technologies and automation in the construction industry. Using topic-specific keywords to organise and summarise pertinent studies, the study undertook a systematic literature review and meta-analysis of robotic technologies and automation in construction. A systematic search of the databases of Scopus, Web of Science, and Dimensions was conducted, with a total of 9,515 journal articles retrieved from them. Based on inclusion and exclusion criteria, a total of 51 research papers met the parameters for meta analysis and systematic review. Data relating to the research papers' demography and to robotic technologies as well as automation in construction were mined, with a quantitative meta-analysis performed on them. The results show a spread of research efforts across Europe, Asia and America, with an increase in research output between 2019 and 2023. The results further show that construction gantry systems, bricklaying robots and 3D concrete printers are the most studied robotic technologies and automation processes in the sector. The study concludes that there is still a paucity of research on robotic technologies and automation in construction. The study therefore recommends further research on robotic technologies and automation in construction, especially with regard to their appropriate application and deployment in construction projects across Africa