Modelling Dynamic Responses of Clamped Non-Uniformly Prestressed Bernoulli-Euler Beams on Variable Elastic Foundations.
Publication Date: 05/03/2025
DOI: 10.52589/AJMSS-SRIJ0ROR
Author(s):
S. A. Jimoh, T. O. Awodola, B. B. Awe, Okoubi Elizabeth.
Volume/Issue:
Volume 8
,
Issue 1
(2025)
Abstract:
This paper examines the dynamic response of a non-uniformly prestressed Bernoulli-Euler beam with clamped-clamped boundary conditions, resting on a variable bi-parametric foundation. The governing equation is a fourth-order partial differential equation with variable and singular coefficients. The primary objective is to derive an analytical solution for this class of dynamic problems. To achieve this, the Galerkin method is applied, utilizing a series representation of the Heaviside function to reduce the equation to a system of second-order ordinary differential equations with variable coefficients. These reduced equations are further simplified using two approaches: (i) the Laplace transform technique, combined with convolution theory, to address problems involving moving forces, and (ii) finite element analysis, integrated with the Newmark method, to solve analytically intractable moving mass problems with harmonic behaviour.
We begin by solving the moving force problem using the finite element method and validate its accuracy by comparing the results with analytical solutions. The numerical solution obtained from the finite element analysis demonstrates strong agreement with the analytical solution, confirming the method’s reliability for tackling more complex moving mass problems that lack closed-form solutions. Finally, we generate displacement response curves for both moving distributed force and moving mass models at different time instances t, providing a comprehensive representation of the system's dynamic behaviour.
Keywords:
Bernoulli-Euler beam, Prestressed, Clamped-Clamped, Newmark method, Bi-parametric foundation.
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Computation of Regular Transitive p-Groups of Order p^n for n>1.
Publication Date: 17/03/2025
DOI: 10.52589/AJMSS-PFTQ2TML
Author(s):
Hamidu A. Adamu, Jeltene B. Naphtali, Mohammad S. Audu.
Volume/Issue:
Volume 8
,
Issue 1
(2025)
Abstract:
Regular elementary group of order a power of primes were computed in regard to suitable algorithms underlined. These was achieved in respct to the designated GAP computation. It was observed that such groups had abelian centralizer and non trivial. The prime order of the groups were for p=5 and p=11. Further the ismorphism classes of such groups were determined upto the order.
Keywords:
Regular elementary abelian groups, transitive groups, isomorphism classes.
No. of Downloads:
0
View: 98
Queuing Theory and its Application to the Optimum Number of ATM Machines Needed to Reduce Waiting Time of Customers in the Queue.
Publication Date: 11/03/2025
DOI: 10.52589/AJMSS-IU8RVUTA
Author(s):
Encho Leo Tanyam, Okolo Abraham, Ayendoh Terrence Sama, O. C. Asogwa.
Volume/Issue:
Volume 8
,
Issue 1
(2025)
Abstract:
Time spent by customers to access a service from banks with single ATM facility is increasingly a major source of concern and justification on the rationale of such waiting. This also imposes a potential threat to customers’ services. In Cameroon, most commercial banks having a single ATM machine with large number of customers have cases where customers may not be attended to on time. The consequences of keeping customers in a queue for too long in order to get service can seriously affect business growth. In this study, the single server queuing models was used to analyze service efficiency of the Credit Communautaire D'Afrique (Community Credit of Africa) (CCA) bank at commercial Avenue Bamenda, Cameroon. Primary data was collected through observation and questionnaire methods at the bank over a ten days period to determine how to minimize the waiting time, expected service time, inter-arrival time and traffic intensity of customers in a queue. An M/M/1 method was considered where the arrival and service time of the customer were both exponentially distributed and with the implementation of a first come first serve. The result showed that increasing the number of ATM machines will reduce the waiting time of customers, overutilization of ATM and provide an optimal satisfaction of customers.
Keywords:
Queue theory, M/M/1, waiting time, arrival rate service time, ATM and Customer Satisfaction.
No. of Downloads:
0
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A Comparative Analysis of Bootstrap and Maximum Likelihood Estimation Methods for Assessing Reliability Index.
Publication Date: 10/03/2025
DOI: 10.52589/AJMSS-6SOFLRUI
Author(s):
Imasuen Kennedy (Ph.D.), George Obed Samuel.
Volume/Issue:
Volume 8
,
Issue 1
(2025)
Abstract:
This study compares bootstrap and maximum likelihood estimation methods for assessing the reliability index using scores from the 2022 National Business and Technical Examination Board (NABTEB) Economics examination. Cronbach's Alpha reliability statistic was applied across various sample sizes (50, 100, 200, 500, 1000, and greater than 1000) to assess measurement reliability. Five confidence interval (CI) estimation methods were utilized: Wald, Profile Likelihood, Bootstrap Percentile, Bias-Corrected and Accelerated (BCa), and Studentized. Findings reveal that SE decreases as sample size increases, demonstrating greater precision with larger samples. The Wald confidence interval, though effective for large samples, proved unreliable for small ones due to its assumption of normality. The Profile Likelihood confidence interval, slightly wider than the Wald confidence interval, better accounted for non-normality. The Bootstrap Percentile confidence interval, a nonparametric approach, provided robust estimates when population distribution assumptions were violated. The BCa method improved accuracy by adjusting for bias and skewness, while the Studentized confidence interval offered conservative estimates, accounting for sample variability. Reliability estimates also increased with sample size. It was therefore recommended that for large samples, use Wald CI; for small samples or skewed data, opt for Profile Likelihood or Bootstrap CIs.
Keywords:
Sample size, Standard error, Confidence intervals, Reliability, Bootstrap.
No. of Downloads:
0
View: 172
