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Doubly Periodic Functions And Floquet Theorem, Nafya H. Mohammed Journal, Nazaneen Q.M. Saeed Apr 2025

Doubly Periodic Functions And Floquet Theorem, Nafya H. Mohammed Journal, Nazaneen Q.M. Saeed

Sultan Qaboos University Journal For Science

In complex analysis, an elliptic function is a meromorphic function that is periodic in two directions. Just as a periodic function of a real variable is defined by its values on an interval, an elliptic function is determined by its values on a fundamental parallelogram, which then repeat in a lattice. Such a doubly periodic function cannot be holomorphic, as it would then be a bounded entire function, and by Liouville's theorem every such function must be constant. Historically, elliptic functions were first discovered by Niels Henrik Abel as inverse functions of elliptic integrals, and their theory was improved by …

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Effects Of Thermal Stratification And Anisotropic Porous Material In A Symmetrically Heated Vertical Channel, Basant K. Jha, Muhammad K. Musa, Abiodun O. Ajibade Apr 2025

Effects Of Thermal Stratification And Anisotropic Porous Material In A Symmetrically Heated Vertical Channel, Basant K. Jha, Muhammad K. Musa, Abiodun O. Ajibade

Sultan Qaboos University Journal For Science

The coexistence in nature of thermally stratified fluids and directionally inclined porous structures abound in geophysical fluid flow. Despite their important applications especially in underground flow, their combined effects on natural convection have not been intensively investigated. This article aims to investigate a fully developed time dependent natural convection of viscous incompressible stably stratified fluid in the presence of anisotropic porous material. The semi analytical solutions of the governing equations for the temperature and velocity fields are obtained using the Laplace Transform Technique, Riemann Sum Approximation and D’Alembert Methods. The choice of the D’Alembert Method is to provide a systematic …

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A Statistical Analysis On Forecasting Prices Of Some Important Food Commodities In Bangladesh, Mohammad Abdullah Al-Mamun, Sheikh Mohammad Sayem, Khondaker Mohammad Mostafizur Rahman, Mohammad Zakir Hossain Apr 2025

A Statistical Analysis On Forecasting Prices Of Some Important Food Commodities In Bangladesh, Mohammad Abdullah Al-Mamun, Sheikh Mohammad Sayem, Khondaker Mohammad Mostafizur Rahman, Mohammad Zakir Hossain

Sultan Qaboos University Journal For Science

This paper investigates the best possible forecasting price models for three important agricultural products in Bangladesh namely potato, onion and garlic using time-series and secondary data from January 2000 to December 2014. The main objective of this paper is to find out the appropriate time series models using some of the latest selection criteria that could describe the best price patterns of the above mentioned three crops. To forecast the prices of the crops, the ARIMA models were used, based on model selection criteria and error statistics among the competing models. The overall findings of the study indicate that the …

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Dimension Reduction And Relaxation Of Johnson’S Method For Two Machines Flow Shop Scheduling Problem, Mekonnen Redi, Mohammad Ikram Apr 2025

Dimension Reduction And Relaxation Of Johnson’S Method For Two Machines Flow Shop Scheduling Problem, Mekonnen Redi, Mohammad Ikram

Sultan Qaboos University Journal For Science

The traditional dimensionality reduction methods can be generally classified into Feature Extraction (FE) and Feature Selection (FS) approaches. The classical FE algorithms are generally classified into linear and nonlinear algorithms. Linear algorithms such as Principal Component Analysis (PCA) aim to project high dimensional data to a lower-dimensional space by linear transformations according to certain criteria. The central idea of PCA is to reduce the dimensionality of the data set consisting of a large number of variables. In this paper, PCA was used to reduce the dimension of flow shop scheduling problems. This mathematical procedure transforms a number of (possibly) correlated …

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Behavior Of Small Variable Mass Particle In Electromagnetic Copenhagen Problem, Abdullah A. Ansari Apr 2025

Behavior Of Small Variable Mass Particle In Electromagnetic Copenhagen Problem, Abdullah A. Ansari

Sultan Qaboos University Journal For Science

The paper presents the behavior of the motion properties of the variable mass test particle (third body), moving under the influence of the two equal primaries having electromagnetic dipoles. These primaries move on the same circular path around their common center of mass in the same plane. We have determined the equations of motion of the test particle whose mass varies according to Jean's law. Using the system of equations of motion we have evaluated the locations of equilibrium points, their movements and basins of the attracting domain. Finally, we examine the stability of these equilibrium points, all of which …

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Finite Element Convergence Analysis Of A Schwarz Alternating Method For Nonlinear Elliptic Pdes, Messaoud Boulbrachene Apr 2025

Finite Element Convergence Analysis Of A Schwarz Alternating Method For Nonlinear Elliptic Pdes, Messaoud Boulbrachene

Sultan Qaboos University Journal For Science

In this paper, we prove uniform convergence of the standard finite element method for a Schwarz alternating procedure for nonlinear elliptic partial differential equations in the context of linear subdomain problems and nonmatching grids. The method stands on the combination of the convergence of linear Schwarz sequences with standard finite element L-error estimate for linear problems.

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Zero-Hopf Bifurcation In The Generalized Stretch-Twist-Fold Flow, Niazy H. Hussein, Azad I. Amen Apr 2025

Zero-Hopf Bifurcation In The Generalized Stretch-Twist-Fold Flow, Niazy H. Hussein, Azad I. Amen

Sultan Qaboos University Journal For Science

A zero-Hopf equilibrium in a three-dimensional system is an isolated equilibrium point which has a zero eigenvalue and a simple pair of purely imaginary eigenvalues. In general, for such an equilibrium, there is no theory for finding when some periodic solutions are bifurcated by perturbing the parameters of the system. In this work, we describe the values of the parameters for which a zero-Hopf equilibrium occurs at the equilibrium points in the generalized stretch-twist-fold flow. Thus, only one condition for parameters of the generalized stretch-twist-fold flow introduced in a system (Eq. 1) is found for which the equilibrium point is …

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Eventually Pointed Principally Ordered Regular Semigroups, G.A. Pinto Apr 2025

Eventually Pointed Principally Ordered Regular Semigroups, G.A. Pinto

Sultan Qaboos University Journal For Science

An ordered regular semigroup, , is said to be principally ordered if for every there exists . A principally ordered regular semigroup is pointed if for every element, we have . Here we investigate those principally ordered regular semigroups that are eventually pointed in the sense that for all there exists a positive integer, , such that . Necessary and sufficient conditions for an eventually pointed principally ordered regular semigroup to be naturally ordered and to be completely simple are obtained. We describe the subalgebra of generated by a pair of comparable idempotents and such that .

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Connected Components Of The Hurwitz Space For The Symmetric Group Of Degree 7, Haval M. Mohammed Salih, University Of Raparian, College Of Basic Education, Department Of Mathematic, Ranya, Kurdistan Region Of Iraq Apr 2025

Connected Components Of The Hurwitz Space For The Symmetric Group Of Degree 7, Haval M. Mohammed Salih, University Of Raparian, College Of Basic Education, Department Of Mathematic, Ranya, Kurdistan Region Of Iraq

Sultan Qaboos University Journal For Science

The Hurwitz space is the space of genus covers of the Riemann sphere with branch points and the monodromy group . Let be the symmetric group . In this paper, we enumerate the connected components of . Our approach uses computational tools, relying on the computer algebra system GAP and the MAPCLASS package, to find the connected components of . This work gives us the complete classification of primitive genus zero symmetric group of degree seven.

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Two Groups 2^3.〖Psl〗_2 (7) And 2^3:〖Psl〗_2 (7) Of Order 1344, Mehmet Koca, Ramazan Koc, Nazife O.Koca Apr 2025

Two Groups 2^3.〖Psl〗_2 (7) And 2^3:〖Psl〗_2 (7) Of Order 1344, Mehmet Koca, Ramazan Koc, Nazife O.Koca

Sultan Qaboos University Journal For Science

No abstract provided.

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An Overview Survey Of Recent Routing Protocols For Underwater Wireless Sensor Networks, Al-Salti Faiza A., Al-Zeidi Nasser M., Day Khaled, Arafeh Bassel, Touzene Abderezak Apr 2025

An Overview Survey Of Recent Routing Protocols For Underwater Wireless Sensor Networks, Al-Salti Faiza A., Al-Zeidi Nasser M., Day Khaled, Arafeh Bassel, Touzene Abderezak

Sultan Qaboos University Journal For Science

With the recent advances in underwater sensor devices and technologies, underwater wireless sensor networks (UWSNs) enable a variety of applications such as underwater exploration and monitoring, disaster prevention, and military surveillance and reconnaissance. However, these kinds of networks faces a number of challenges induced by the nature of the underwater environment and its influence on the physical media. Therefore, new routing protocols are proposed specifically for such networks to mitigate these challenges. This paper surveys some of the recent routing protocols for UWSNs. Specifically, the idea of each protocol is presented as well as its advantages and disadvantages. Furthermore, the …

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Initial And Boundary Value Problems For Fractional Differential Equations Involving Atangana-Baleanu Derivative, Al-Musalhi Fatma S., Al-Salti Nasser S., 2fracdiff Research Group, Sultan Qaboos University, Muscat, Sultanate Of Oman, Karimov Erkinjon, Institute Of Mathematics, Uzbekistan Academy Of Sciences, Tashkent 170, Uzbekistan Apr 2025

Initial And Boundary Value Problems For Fractional Differential Equations Involving Atangana-Baleanu Derivative, Al-Musalhi Fatma S., Al-Salti Nasser S., 2fracdiff Research Group, Sultan Qaboos University, Muscat, Sultanate Of Oman, Karimov Erkinjon, Institute Of Mathematics, Uzbekistan Academy Of Sciences, Tashkent 170, Uzbekistan

Sultan Qaboos University Journal For Science

In the present work, an initial value problem involving the Atangana-Baleanu derivative is considered. An explicit solution of the given problem in integral form is obtained by using the Laplace transform. The use of the given initial value problem is illustrated by considering a boundary value problem in which the solution is expressed in the form of a series expansion using an orthogonal basis obtained by separation of variables. Some examples are also given to illustrate the obtained results.

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A One-Dimensional Model Of Thermo-Electroelasticity In Extended Thermodynamics, Moustafa Saber Abou-Dina, Ahmed Ahmed F. Ghaleb Apr 2025

A One-Dimensional Model Of Thermo-Electroelasticity In Extended Thermodynamics, Moustafa Saber Abou-Dina, Ahmed Ahmed F. Ghaleb

Sultan Qaboos University Journal For Science

The subject of thermo-electroelasticity involves many complications due to the multiple ways in which the mechanical, thermal and electric fields can interact, some of these involving non-linearities. In extended thermodynamics, an additional difficulty arises due to the requirement of finiteness of the speed of propagation of the thermal disturbances. This implies, as may be observed in the extensive literature on the subject, a re-visiting of the basic postulates of thermodynamics, ultimately leading to the desired generalization. There are only a few nonlinear models dealing with this subject. In order to consider general nonlinear models, it is necessary to study linear …

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The Mathematical Modelling Of A Fixed Source Of Dust, Khaled S.M. Al-Mashrafi Apr 2025

The Mathematical Modelling Of A Fixed Source Of Dust, Khaled S.M. Al-Mashrafi

Sultan Qaboos University Journal For Science

A mathematical model for the diffusion of dust particles emitted from a fixed source is investigated using the atmospheric diffusion equation. This model poses an initial boundary value problem with a second order linear partial differential equation. The steady state case of this problem when the uniform source is situated at ground level was examined by Sharan et al. [1]. The solution of the unsteady case in closed form for a time dependent source is derived. Two special cases, in which the source function of time is explicitly given and special values of the diffusion parameters are taken, are examined …

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Numerical Simulations Of A Delay Model For Immune System-Tumor Interaction, Mohamed A. Hajji, Qasem Al-Mdallal Apr 2025

Numerical Simulations Of A Delay Model For Immune System-Tumor Interaction, Mohamed A. Hajji, Qasem Al-Mdallal

Sultan Qaboos University Journal For Science

In this paper we consider a system of delay differential equations as a model for the dynamics of tumor-immune system interaction. We carry out a stability analysis of the proposed model. In particular, we show that the system can have up to two steady states: the tumor free steady state, which always exist, and the tumor persistent steady state, which exists only when the relative rate of increase of the tumor cells exceeds the ratio between the natural proliferation rate and the relative death rate of the effector cells. We also determine an upper bound for the delay, such that …

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A New Second Order Approximation For Fractional Derivatives With Applications, Haniffa M.Nasir, Kamel Nafa Apr 2025

A New Second Order Approximation For Fractional Derivatives With Applications, Haniffa M.Nasir, Kamel Nafa

Sultan Qaboos University Journal For Science

We propose a generalized theory to construct higher order Grünwald type approximations for fractional derivatives. We use this generalization to simplify the proofs of orders for existing approximation forms for the fractional derivative. We also construct a set of higher order Grünwald type approximations for fractional derivatives in terms of a general real sequence and its generating function. From this, a second order approximation with shift is shown to be useful in approximating steady state problems and time dependent fractional diffusion problems. Stability and convergence for a Crank-Nicolson type scheme for this second order approximation are analyzed and are supported …

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Heat Transfer In Fe3o4-H2o Nanofluid Contained In A Triangular Cavity Under A Sloping Magnetic Field, Mohammad M.Rahman Apr 2025

Heat Transfer In Fe3o4-H2o Nanofluid Contained In A Triangular Cavity Under A Sloping Magnetic Field, Mohammad M.Rahman

Sultan Qaboos University Journal For Science

Numerical simulation is performed to explore the convective heat transfer characteristics of Fe3O4-H2O nanofluid contained in a right-angle triangular cavity considering three types of thermal boundary conditions at the bottom wall. No heat is allowed to escape through the insulated vertical wall, whereas the inclined wall is kept colder than the bottom one. A sloping magnetic field whose strength is unvarying acts upon the cavity. The physical model is converted to the mathematical form through coupled highly nonlinear partial differential equations. These equations are then transformed into the non-dimensional form with the help of a group of transformations of variables. …

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Development Of A Mathematical Model For Simulation Of Macroalgae Farming In The Coastal Areas, Abdolmajid Lababpour Apr 2025

Development Of A Mathematical Model For Simulation Of Macroalgae Farming In The Coastal Areas, Abdolmajid Lababpour

Sultan Qaboos University Journal For Science

A mathematical model consisting of a system of three coupled partial differential equations (PDEs) was proposed to estimate the concentrations of nitrogen, phosphorous and macroalgae biomass in coastal open waters. However, some simplifying assumptions were used in the model to cope with the complexity of real conditions. For the macroalgae biomass, the system works as a batch mode, while input and output were accounted for nitrogen and phosphorous. The MATLAB pdepe feature, applying the finite element method was used in model solving and the simulation of model equations. The program was split into four functions that included the solver and …

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Inequalities Concerning The Growth Of Polynomials, Bashir A.Zargar, Ahmad W.Manzoor Apr 2025

Inequalities Concerning The Growth Of Polynomials, Bashir A.Zargar, Ahmad W.Manzoor

Sultan Qaboos University Journal For Science

In this paper we consider a polynomial having no zeros in the disk . We investigate the dependence of on and obtain a refinement of a famous result due to Rivilin ([5], [7]). Our results not only generalize some polynomial inequalities but also refine a result by Aziz [1].

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Approximation Properties Of De La Vallée-Poussin Sums In Morrey Spaces, Ahmed Kinj, Mohammad Ali, Suleiman Mahmoud Apr 2025

Approximation Properties Of De La Vallée-Poussin Sums In Morrey Spaces, Ahmed Kinj, Mohammad Ali, Suleiman Mahmoud

Sultan Qaboos University Journal For Science

In this paper, we investigate the problem of the deviation of a function from its de la Vallée-Poussin sums of Fourier series in Morrey spaces defined on the unite circle in terms of the best approximation to . Moreover, approximation properties of de la Vallée-Poussin sums of Faber series in Morrey-Smirnov classes of analytic functions, defined on a simply connected domain bounded by a curve satisfying Dini's smoothness condition are obtained.

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An Evaluation Of The Mathematics Foundation Course In Sultan Qaboos University: Does High School Performance Matter?, Mohammad Mazharul Islam, Asma Al-Ghassani, Ahmed Y.S. Al-Hadhrami Apr 2025

An Evaluation Of The Mathematics Foundation Course In Sultan Qaboos University: Does High School Performance Matter?, Mohammad Mazharul Islam, Asma Al-Ghassani, Ahmed Y.S. Al-Hadhrami

Sultan Qaboos University Journal For Science

Although the mathematics foundation program was introduced in Sultan Qaboos University (SQU) half a decade ago, there has been no evaluation or assessment of the program. The aim of this study was to evaluate the students’ performance in the Mathematics foundation course in SQU and to examine the predictive value of a student’s high school performance for success in the math foundation course. The study considered a sample of 551 students who took the math course (MATH2107) during 2014 Spring semester. More than 95% of the students were admitted to SQU with a high school score of 80 and above. …

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Finite Element Approximation Of Variational Inequalities: An Algorithmic Approach, Messaoud Boulbrachene Apr 2025

Finite Element Approximation Of Variational Inequalities: An Algorithmic Approach, Messaoud Boulbrachene

Sultan Qaboos University Journal For Science

In this paper, we introduce a new method to analyze the convergence of the standard finite element method for elliptic variational inequalities with noncoercive operators (VI). The method consists of combining the so-called Bensoussan-Lions algorithm with the characterization of the solution, in both the continuous and discrete contexts, as fixed point of contraction. Optimal error estimates are then derived, first between the continuous algorithm and its finite element counterpart, and then between the true solution and the approximate solution.

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Connected Components Of H_(R,G)^A (G), Haval M. Mohammed Salih Apr 2025

Connected Components Of H_(R,G)^A (G), Haval M. Mohammed Salih

Sultan Qaboos University Journal For Science

The Hurwitz space is the space of genus g covers of the Riemann sphere with branch points and the monodromy group . In this paper, we enumerate the connected components of the Hurwitz spaces for a finite primitive group of degree 7 and genus zero except . We achieve this with the aid of the computer algebra system GAP and the MAPCLASS package.

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Teaching Statistics To Engineering Students – An Australian Experience Of Using Educational Technologies, Shahjahan Khan, Department Of Mathematics And Statistics, College Of Science, Sultan Qaboos University, Oman, Mohammad Mrk Khadem, Sujan Piya Apr 2025

Teaching Statistics To Engineering Students – An Australian Experience Of Using Educational Technologies, Shahjahan Khan, Department Of Mathematics And Statistics, College Of Science, Sultan Qaboos University, Oman, Mohammad Mrk Khadem, Sujan Piya

Sultan Qaboos University Journal For Science

Engineers require scientific methods whereby models are developed to explain real phenomena. Model building, data collection, data analysis, and data interpretation form the very core of any sound engineering practice. Therefore statistical methodologies are vital components in engineering curricula and engineers should have the ability to think statistically when dealing with data. They should learn how to design and conduct well-planned experiments to improve the efficiency of the process and the quality of products, and must learn to deal with data, and interpret results produced as a part of their data analysis skills. Statistical methods are vital in engineering practices …

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Incidence Matrices Of Directed Graphs Of Groups And Their Up-Down Pregroups, Wadhah S. Jassim Apr 2025

Incidence Matrices Of Directed Graphs Of Groups And Their Up-Down Pregroups, Wadhah S. Jassim

Sultan Qaboos University Journal For Science

The aim of this work is to give a definition of the incidence matrices of the directed graph of groups, construct an up-down pregroup of the incidence matrices of the directed graph of groups and then give an algorithm for the up-down pregroup of the directed graph of groups.

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Theorems On Fixed Points For Asymptotically Regular Sequences And Maps In, Mohammad S. Khan, Pankaj K. Jhade Apr 2025

Theorems On Fixed Points For Asymptotically Regular Sequences And Maps In, Mohammad S. Khan, Pankaj K. Jhade

Sultan Qaboos University Journal For Science

In this paper, we present some fixed point theorems for asymptotically regular sequences and asymptotically regular maps in complete

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Finite Dimensional Chebyshev Subspaces Of Lo, Aref K. Kamal Apr 2025

Finite Dimensional Chebyshev Subspaces Of Lo, Aref K. Kamal

Sultan Qaboos University Journal For Science

If A is a subset of the normed linear space X, then A is said to be proximinal in X if for each xÎX there is a point y0ÎA such that the distance between x and A; d(x, A) = inf{||x-y||: yÎA}= ||x­-y0||. The element y0 is called a best approximation for x from A. If for each xÎX, the best approximation for x from A is unique then the subset A is called a Chebyshev subset of X. In this paper the author studies the existence of finite dimensional Chebyshev subspaces of Lo.

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Combined Effects Of Hall Current And Heat Transfer On Peristaltic Transport Of A Nanofluid In A Vertical Tapered Channel Through A Porous Medium, Ahmed I. Abdellateef, Syed Z. Ul Haque Apr 2025

Combined Effects Of Hall Current And Heat Transfer On Peristaltic Transport Of A Nanofluid In A Vertical Tapered Channel Through A Porous Medium, Ahmed I. Abdellateef, Syed Z. Ul Haque

Sultan Qaboos University Journal For Science

The influences of Hall currents and heat transfer on peristaltic transport of a nanofluid in a vertical porous tapered channel through a porous medium are investigated theoretically and graphically under the assumptions of low Reynolds number and long wavelength and the flow investigated is in a wavy frame of reference. Analytical solutions are obtained for temperature, axial velocity, stream function and pressure gradient. Graphical results are sketched for various embedded parameters.

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Global Dynamics And Sensitivity Analysis Of A Vector-Host-Reservoir Model, Ibrahim M. Elmojtaba, Santanu Biswas, Joydev Chattopadhyay Apr 2025

Global Dynamics And Sensitivity Analysis Of A Vector-Host-Reservoir Model, Ibrahim M. Elmojtaba, Santanu Biswas, Joydev Chattopadhyay

Sultan Qaboos University Journal For Science

The role of animal reservoir in the disease dynamics is not yet properly studied. In the present investigation a mathematical model of a vector-host-reservoir is proposed and analyzed to observe the global dynamics of the disease. We observe that the disease free equilibrium is globally asymptotically stable if the basic reproduction number ( ) is less than unity whereas unique positive equilibrium is globally asymptotically stable if and transcritical bifurcation occurs at . Our numerical result suggests that the biting rate plays an important role for the propagation of the disease and the recovery rate has not such important contribution …

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4d Pyritohedral Symmetry, Nazife O. Koca, Amal J.H. Al Qanobi, Mehmet Koca Apr 2025

4d Pyritohedral Symmetry, Nazife O. Koca, Amal J.H. Al Qanobi, Mehmet Koca

Sultan Qaboos University Journal For Science

We describe an extension of the pyritohedral symmetry in 3D to 4-dimensional Euclidean space and construct the group elements of the 4D pyritohedral group of order 576 in terms of quaternions. It turns out that it is a maximal subgroup of both the rank-4 Coxeter groups W (F4) and W (H4), implying that it is a group relevant to the crystallographic as well as quasicrystallographic structures in 4-dimensions. We derive the vertices of the 24 pseudoicosahedra, 24 tetrahedra and the 96 triangular pyramids forming the facets of the pseudo snub 24-cell. It turns out that the relevant lattice is the …

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