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Articles 421 - 450 of 11790
Full-Text Articles in Physical Sciences and Mathematics
Another Characterization Of Warped Product Submanifolds Of Nearly Cosymplectic Manifolds, Ali H. Alkhaldi, Abid Kamal
Another Characterization Of Warped Product Submanifolds Of Nearly Cosymplectic Manifolds, Ali H. Alkhaldi, Abid Kamal
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we study warped product pseudo-slant submanifolds of nearly cosymplectic manifolds. First, we derive the integrability conditions of the distributions and then, we investigate the geometry of the leaves of both distributions. Also, we prove a characterization theorem for a pseudo-slant submanifold to be locally a warped product manifold.
Soret Effect On Transient Mhd Convective Flow Past A Semi-Infinite Vertical Porous Plate With Heat Sink And Chemical Reaction, K. Choudhury, N. Ahmed
Soret Effect On Transient Mhd Convective Flow Past A Semi-Infinite Vertical Porous Plate With Heat Sink And Chemical Reaction, K. Choudhury, N. Ahmed
Applications and Applied Mathematics: An International Journal (AAM)
This problem concerns with an analytical study of heat and mass transfer on unsteady MHD convective flow past a semi-infinite porous vertical plate in presence of thermal diffusion, heat sink and chemical reaction. A uniform magnetic field is imposed transversely to the plate. The governing equations are solved by perturbation technique. The expressions for the velocity, temperature and concentration fields as well as transport properties are obtained in non-dimensional form. The influence of the physical parameters like magnetic field parameter, Schmidt number, Prandtl number, heat sink parameter, chemical reaction parameter and Soret number on these fields is discussed through graphs …
Almost Periodic Functions In Quantum Calculus, Martin Bohner, Jaqueline Godoy Mesquita
Almost Periodic Functions In Quantum Calculus, Martin Bohner, Jaqueline Godoy Mesquita
Mathematics and Statistics Faculty Research & Creative Works
In this article, we introduce the concepts of Bochner and Bohr almost periodic functions in quantum calculus and show that both concepts are equivalent. Also, we present a correspondence between almost periodic functions defined in quantum calculus and N0, proving several important properties for this class of functions. We investigate the existence of almost periodic solutions of linear and nonlinear q-difference equations. Finally, we provide some examples of almost periodic functions in quantum calculus.
Energy Demand And Water Footprint Study Of An Agricultural Machinery Industry, Mantoam E,J., Mesfin Mekonnen, T.L. Romanelli
Energy Demand And Water Footprint Study Of An Agricultural Machinery Industry, Mantoam E,J., Mesfin Mekonnen, T.L. Romanelli
Daugherty Water for Food Global Institute: Faculty Publications
The intensification of agricultural production systems demands power, supplied by agricultural machinery, besides more agricultural inputs such as fertilizers, pesticides and seeds. Agricultural mechanization provides increase in the global production of food, fiber and bioenergy; and it brought economic benefits to producers, but causing larger energy consumption. Energy embodiment in agricultural machinery has been done in earlier studies, but data usually are from car industry. This study aimed to determine the energy demand and water footprint in a plant that assembles five types of agricultural machinery from a multinational manufacturer located in Piracicaba municipality in Sao Paulo state, Brazil. That …
H2 Oxidation Over Supported Au Nanoparticle Catalysts: Evidence For Heterolytic H2 Activation At The Metal-Support Interface, Todd N. Whittaker, K. B. Sravan Kumar, Christine Peterson, Meagan N. Pollock, L. C. Grabow, Bert D. Chandler
H2 Oxidation Over Supported Au Nanoparticle Catalysts: Evidence For Heterolytic H2 Activation At The Metal-Support Interface, Todd N. Whittaker, K. B. Sravan Kumar, Christine Peterson, Meagan N. Pollock, L. C. Grabow, Bert D. Chandler
Chemistry Faculty Research
Water adsorbed at the metal-support interface (MSI) plays an important role in multiple reactions. Due to its importance in CO preferential oxidation (PrOx), we examined H2 oxidation kinetics in the presence of water over Au/TiO2 and Au/Al2O3 catalysts, reaching the following mechanistic conclusions: (i) O2 activation follows a similar mechanism to that proposed in CO oxidation catalysis; (ii) weakly adsorbed H2O is a strong reaction inhibitor; (iii) fast H2 activation occurs at the MSI, and (iv) H2 activation kinetics are inconsistent with traditional dissociative H2 chemisorption on metals. Density …
Properties Of The Secondary Hochschild Homology, Jacob Laubacher
Properties Of The Secondary Hochschild Homology, Jacob Laubacher
Faculty Creative and Scholarly Works
Abstract. In this paper we study properties of the secondary Hochschild homology of the triple (A, B, ε) with coefficients in M. We establish a type of Morita equivalence between two triples and show that H•((A, B, ε);M) is invariant under this equivalence. We also prove the existence of an exact sequence which connects the usual and the secondary Hochschild homologies in low dimension, allowing one to perform easy computations. The functoriality of H•((A, B, ε);M) is also discussed.
Transient Solution Of An M/M/1 Retrial Queue With Reneging From Orbit, A. Azhagappan, E. Veeramani, W. Monica, K. Sonabharathi
Transient Solution Of An M/M/1 Retrial Queue With Reneging From Orbit, A. Azhagappan, E. Veeramani, W. Monica, K. Sonabharathi
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, the transient behavior of an M/M/1 retrial queueing model is analyzed where the customers in the orbit possess the reneging behavior. There is no waiting room in the system for the arrivals. If the server is not free when the occurrence of an arrival, the arriving customer moves to the waiting group, known as orbit and retries for his service. If the server is idle when an arrival occurs (either coming from outside the queueing system or from the waiting group), the arrival immediately gets the service and leaves the system. Each individual customer in the orbit, …
An M^X/G(A,B)/1 Queue With Breakdown And Delay Time To Two Phase Repair Under Multiple Vacation, G. Ayyappan, M. Nirmala
An M^X/G(A,B)/1 Queue With Breakdown And Delay Time To Two Phase Repair Under Multiple Vacation, G. Ayyappan, M. Nirmala
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we consider an Mx /G(a,b)/1 queue with active breakdown and delay time to two phase repair under multiple vacation policy. A batch of customers arrive according to a compound Poisson process. The server serves the customers according to the “General Bulk Service Rule” (GBSR) and the service time follows a general (arbitrary) distribution. The server is unreliable and it may breakdown at any instance. As the result of breakdown, the service is suspended, the server waits for the repair to start and this waiting time is called as „delay time‟ and is assumed to follow general …
Fibonacci And Lucas Differential Equations, Esra Erkus-Duman, Hakan Ciftci
Fibonacci And Lucas Differential Equations, Esra Erkus-Duman, Hakan Ciftci
Applications and Applied Mathematics: An International Journal (AAM)
The second-order linear hypergeometric differential equation and the hypergeometric function play a central role in many areas of mathematics and physics. The purpose of this paper is to obtain differential equations and the hypergeometric forms of the Fibonacci and the Lucas polynomials. We also write again these polynomials by means of Olver’s hypergeometric functions. In addition, we present some relations between these polynomials and the other well-known functions.
Approximate Analytical Solutions Of Space-Fractional Telegraph Equations By Sumudu Adomian Decomposition Method, Hasib Khan, Cemil Tunç, Rahmat A. Khan, Akhtyar G. Shirzoi, Aziz Khan
Approximate Analytical Solutions Of Space-Fractional Telegraph Equations By Sumudu Adomian Decomposition Method, Hasib Khan, Cemil Tunç, Rahmat A. Khan, Akhtyar G. Shirzoi, Aziz Khan
Applications and Applied Mathematics: An International Journal (AAM)
The main goal in this work is to establish a new and efficient analytical scheme for space fractional telegraph equation (FTE) by means of fractional Sumudu decomposition method (SDM). The fractional SDM gives us an approximate convergent series solution. The stability of the analytical scheme is also studied. The approximate solutions obtained by SDM show that the approach is easy to implement and computationally very much attractive. Further, some numerical examples are presented to illustrate the accuracy and stability for linear and nonlinear cases.
Thermoelastic Stress Analysis Of A Functionally Graded Transversely Isotropic Hollow Cylinder In Elliptical Coordinates, Tara Dhakate, Vinod Varghese, Lalsingh Khalsa
Thermoelastic Stress Analysis Of A Functionally Graded Transversely Isotropic Hollow Cylinder In Elliptical Coordinates, Tara Dhakate, Vinod Varghese, Lalsingh Khalsa
Applications and Applied Mathematics: An International Journal (AAM)
This paper is concerned with the axisymmetric thermoelastic problem to investigate the influence of nonlinear heat conduction equation, displacement functions and thermal stresses of a functionally graded transversely isotropic hollow cylinder that is presented in the elliptical coordinate system. The method of integral transform technique is used to produce an exact solution of the heat conduction equation in which sources are generated according to a linear function of the temperature. An explicit exact solution of the governing thermoelastic equation is proposed when material properties are power-law functions with the exponential form of the radial coordinate. Numerical calculations are also carried …
Quasi-Linearization Method With Rational Legendre Collocation Method For Solving Mhd Flow Over A Stretching Sheet With Variable Thickness And Slip Velocity Which Embedded In A Porous Medium, M. M. Khader
Applications and Applied Mathematics: An International Journal (AAM)
The quasi-linearization method (QLM) and the rational Legendre functions are introduced here to present the numerical solution for the Newtonian fluid flow past an impermeable stretching sheet which embedded in a porous medium with a power-law surface velocity, variable thickness and slip velocity. Firstly, due to the high nonlinearity which yielded from the ordinary differential equation which describes the proposed physical problem, we construct a sequence of linear ODEs by using the QLM, hence the resulted equations become a system of linear algebraic equations. The comparison with the available results in the literature review proves that the obtained results via …
Η-Ricci Soliton On 3-Dimensional F-Kenmotsu Manifolds, S. K. Hui, S. K. Yadav, S. K. Chaubey
Η-Ricci Soliton On 3-Dimensional F-Kenmotsu Manifolds, S. K. Hui, S. K. Yadav, S. K. Chaubey
Applications and Applied Mathematics: An International Journal (AAM)
The object of the present paper is to carry out η-Ricci soliton on 3-dimensional regularf-Kenmotsu manifold and we turn up some geometrical results. Furthermore we bring out the curvature conditions for which η-Ricci soliton on such manifolds are shrinking, steady or expanding. We wind up by considering examples of existence of shrinking and expanding η-Ricci soliton on 3-dimensional regularf-Kenmotsu manifolds.
Global Range Restricted Gmres For Linear Systems With Multiple Right Hand Sides, Mostafa Eslami
Global Range Restricted Gmres For Linear Systems With Multiple Right Hand Sides, Mostafa Eslami
Applications and Applied Mathematics: An International Journal (AAM)
This work concerns the solution of non-symmetric, sparse linear systems with multiple right hand sides by iterative methods. Herein a global version of the range restricted generalized minimal residual method (RRGMRES) is proposed for solving this sort of problems. Numerical results confirm that this new algorithm is applicable.
Non-Existence Of Hopf Real Hypersurfaces In Complex Quadric With Recurrent Ricci Tensor, Pooja Bansal, Mohammad H. Shahid
Non-Existence Of Hopf Real Hypersurfaces In Complex Quadric With Recurrent Ricci Tensor, Pooja Bansal, Mohammad H. Shahid
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we first introduce the notion of recurrent Ricci tensor which is the generalization of parallel Ricci tensor in the complex quadric Qm = SOm+2 /SOm SO2. After then, we investigate real hypersurfaces of the complex quadric Qm with the condition of recurrent Ricci tensor and give the glimpse of full classification with this condition.
Similarity Analysis Of Three Dimensional Nanofluid Flow By Deductive Group Theoretic Method, Hemangini Shukla, Hema C. Surati, M. G. Timol
Similarity Analysis Of Three Dimensional Nanofluid Flow By Deductive Group Theoretic Method, Hemangini Shukla, Hema C. Surati, M. G. Timol
Applications and Applied Mathematics: An International Journal (AAM)
The objective of this paper is to obtain similarity solution of three-dimensional nanofluid flow over flat surface stretched continuously in two lateral directions. Two independent variables from governing equations are reduced by applying deductive two parameter group theoretical method. Partial differential equations with boundary conditions are converted into ordinary differential equations with appropriate boundary conditions. Obtained equations are solved for temperature and velocity. The effect of nanoparticles volume fraction on temperature and velocity profile is investigated.
An Investigatiozn On Prime And Semiprime Fuzzy Hyperideals In Po-Ternary Semihypergroups, Aakif F. Talee, M. Y. Abbasi, S. A. Khan
An Investigatiozn On Prime And Semiprime Fuzzy Hyperideals In Po-Ternary Semihypergroups, Aakif F. Talee, M. Y. Abbasi, S. A. Khan
Applications and Applied Mathematics: An International Journal (AAM)
The aim of this paper is to apply the concept of fuzzification on prime hyperideals and semiprime hyperideals in po-ternary semihypergroups and look for some of their related characteristics. Moreover, a number of characterizations for intra-regular po-ternary semihypergroups had been given by using the concept of fuzzy hyperideals.
Fractional Order Thermoelastic Thick Circular Plate With Two Temperatures In Frequency Domain, Parveen Lata
Fractional Order Thermoelastic Thick Circular Plate With Two Temperatures In Frequency Domain, Parveen Lata
Applications and Applied Mathematics: An International Journal (AAM)
The present investigation is concerned with thermomechanical interactions in the fractional theory of thermoelasticity for a homogeneous isotropic thick circular plate in the light of two-temperature thermoelasticity theory in frequency domain. The upper and lower surfaces of the thick plate are traction free and subjected to an axisymmetric heat supply. The solution is found by using Hankel transform technique and a direct approach without the use of potential functions. The analytical expressions of displacement components, stresses, conductive temperature, temperature change and cubic dilatation are computed in transformed domain. Numerical inversion technique has been applied to obtain the results in the …
Analysis Of Batch Arrival Bulk Service Queue With Multiple Vacation Closedown Essential And Optional Repair, G. Ayyappan, T. Deepa
Analysis Of Batch Arrival Bulk Service Queue With Multiple Vacation Closedown Essential And Optional Repair, G. Ayyappan, T. Deepa
Applications and Applied Mathematics: An International Journal (AAM)
The objective of this paper is to analyze an queueing model with multiple vacation, closedown, essential and optional repair. Whenever the queue size is less than , the server starts closedown and then goes to multiple vacation. This process continues until at least customer is waiting in the queue. Breakdown may occur with probability when the server is busy. After finishing a batch of service, if the server gets breakdown with a probability , the server will be sent for repair. After the completion of the first essential repair, the server is sent to the second optional repair with probability …
On Chaplygin’S Method For First Order Neutral Differential Equation, Mamta Kumari, Y. S. Valaulikar
On Chaplygin’S Method For First Order Neutral Differential Equation, Mamta Kumari, Y. S. Valaulikar
Applications and Applied Mathematics: An International Journal (AAM)
In this paper we discuss the existence of a solution of a first order neutral differential equation with piecewise constant argument. We extend the method of Chaplygin’s sequence to obtain two sided bounds for the solution. These bounds are in the form of sequences of functions which are solutions of associated linear neutral differential equations with piecewise constant argument. This construction of monotonic sequences of upper and lower functions approximate, with increasing accuracy, the desired solution of the neutral differential equation with piecewise constant argument. Further we show that these sequences converge uniformly and monotonically to the unique solution of …
Numerical Studies For Mhd Flow And Gradient Heat Transport Past A Stretching Sheet With Radiation And Heat Production Via Dtm, Khadijah M. Abualnaja
Numerical Studies For Mhd Flow And Gradient Heat Transport Past A Stretching Sheet With Radiation And Heat Production Via Dtm, Khadijah M. Abualnaja
Applications and Applied Mathematics: An International Journal (AAM)
This paper presents a numerically study for the effect of the internal heat generation, magnetic field and thermal radiation effects on the flow and gradient heat transfer of a Newtonian fluid over a stretching sheet. By using a similarity transformation, the governing PDEs can be transformed into a coupled non-linear system of ODEs with variable coefficients. Numerical solutions for these equations subject to appropriate boundary conditions are obtained by using the differential transformation method (DTM). The effects of various physical parameters such as viscosity parameter, the suction parameter, the radiation parameter, internal heat generation or absorption parameter and the Prandtl …
Mathematica Program To Compute Klein Gordon Equation For Generic Black Holes, Brant Smith
Mathematica Program To Compute Klein Gordon Equation For Generic Black Holes, Brant Smith
Physics Capstone Projects
The goal of this project is to develop a program that will compute the Klein Gordon equation for generic Black Holes through the program Mathematica. This program will be available on Utah State websites for public usage. This project focuses on an understanding of General Relativity and more concretely on theoretical aspects of Black Holes. Developing the program begins with computing the Laplace equation in flat space to understand what it means to have empty space without a Black Hole. The Klein Gordon equation for a Schwarzschild Black Hole is then solved to show what happens once a static, non-rotating …
Batch Arrival Bulk Service Queue With Unreliable Server, Second Optional Service, Two Different Vacations And Restricted Admissibility Policy, G. Ayyappan, R. Supraja
Batch Arrival Bulk Service Queue With Unreliable Server, Second Optional Service, Two Different Vacations And Restricted Admissibility Policy, G. Ayyappan, R. Supraja
Applications and Applied Mathematics: An International Journal (AAM)
This paper is concerned with batch arrival queue with an additional second optional service to a batch of customers with dissimilar service rate where the idea of restricted admissibility of arriving batch of customers is also introduced. The server may take two different vacations (i) Emergency vacation-during service the server may go for vacation to an emergency call and after completion of the vacation, the server continues the remaining service to a batch of customers. (ii) Bernoulli vacation-after completion of first essential or second optional service, the server may take a vacation or may remain in the system to serve …
The Circular Restricted Four-Body Problem With Triaxial Primaries And Variable Infinitesimal Mass, Abdullah A. Ansari
The Circular Restricted Four-Body Problem With Triaxial Primaries And Variable Infinitesimal Mass, Abdullah A. Ansari
Applications and Applied Mathematics: An International Journal (AAM)
This paper investigates the circular restricted four-body problem in which three primaries are taken as triaxial rigid body which are placed at the vertices of an equilateral triangle and the fourth infinitesimal body is varying its mass with time. We used the Jeans law to determine equations of motion and then evaluated the Jacobi integral. In the next section, we have performed the computational work to draw the graphs of the equilibrium points in different planes, zero velocity curves, surfaces and the Newton-Raphson basins of attraction with the variations of the triaxiality parameters. Finally, we have examined the linear stability …
The Basins Of Convergence In The Planar Restricted Four-Body Problem With Variable Mass, Amit Mittal, Monika Arora, Md S. Suraj, Rajiv Aggarwal
The Basins Of Convergence In The Planar Restricted Four-Body Problem With Variable Mass, Amit Mittal, Monika Arora, Md S. Suraj, Rajiv Aggarwal
Applications and Applied Mathematics: An International Journal (AAM)
We have studied the existence, location and stability of the libration points in the model of restricted four-body problem (R4BP) with variable mass. It is assumed that three primaries, one dominant primary and the other two with equal masses, are always forming an equilateral triangle. We have determined the equations of motion of the above mentioned problem for the fourth body which is an infinitesimal mass. The libration points have been determined numerically for different values of the parameters considered. It is found that there are eight or ten libration points out of which six are non-collinear and two or …
Learning-Based Analysis On The Exploitability Of Security Vulnerabilities, Adam Bliss
Learning-Based Analysis On The Exploitability Of Security Vulnerabilities, Adam Bliss
Computer Science and Computer Engineering Undergraduate Honors Theses
The purpose of this thesis is to develop a tool that uses machine learning techniques to make predictions about whether or not a given vulnerability will be exploited. Such a tool could help organizations such as electric utilities to prioritize their security patching operations. Three different models, based on a deep neural network, a random forest, and a support vector machine respectively, are designed and implemented. Training data for these models is compiled from a variety of sources, including the National Vulnerability Database published by NIST and the Exploit Database published by Offensive Security. Extensive experiments are conducted, including testing …
Assessment Of Drinking Water/Aquifer Vulnerability To Contamination By Natural Manganese And Anthropogenic Chemicals In The U.S., Ryan Kelly
Sustainability and Social Justice
Aquifers in the U.S. store groundwater used by many Americans every day for drinking eating, bathing and cleaning. These underground sources of water are vital to life and may be subject to contamination from both natural and anthropogenic pollution, including manganese (Mn) – especially shallow aquifers (<100 feet to bedrock). Natural sources of Mn are found in soils, surficial deposits, and bedrock, while anthropogenic contamination derives from landfills, waste facilities, or industries that use toxic materials. Pollutants like Mn raise concern because there is no policy in place to enforce regulation of Mn levels in water supplies based on limited information about health effects. Yet studies have shown elevated levels of Mn intake can lead to adverse human health effects. This study uses ArcMap to identify potential sources of Mn and/or toxics contamination in shallow U.S. aquifers based on geologic characteristics of a given aquifer source and proximity to waste sites. The results show approximately 2 million Americans may be at risk of consuming water with natural Mn contamination, and of those 2 million, close to 1.7 million are also vulnerable to additional toxics from anthropogenic waste. …100>
A New Generation Of Functional Polyisobutylenes For Advanced Applications, Corey M. Parada
A New Generation Of Functional Polyisobutylenes For Advanced Applications, Corey M. Parada
Dissertations
Polyisobutylene (PIB) is a fully saturated, aliphatic polymer of high commercial importance due to its superior gas barrier properties and high chemical/oxidative stability. One commercial end-use for PIB is in insulated glass windows (IGU), where it acts as a gas/moisture barrier and sealant. Under certain adverse conditions, catastrophic failure of the PIB sealant may result in aesthetic and functional failure of the IGU, which necessitates replacement of the unit. Thus, there exists a need to improve current generations of thermoplastic PIB sealants to be able to withstand the harsh environments found in current real-world applications.
In the first project, we …
Polyhedral Oligomeric Silsesquioxane-Phosphate Glass Matrix Nanocomposites With Additional Chapter On Phosphate Glass-Poly(Ethylene Terephthalate) Matrix Composites, Kyoungtae Kim
Dissertations
Preparation and characterization of tin fluorophosphate glass (Pglass) matrix nanocomposites incorporating polyhedral oligomeric silsesquioxane (POSS) were investigated on the structural, thermal, morphological, mechanical, and rheological properties. Various processes including synthesis, extrusion and sintering processes were applied to prepare the nanocomposite samples. Another application of POSS with hydrophobic functional groups on the well-structured nanoscale silicate cage with three silanol groups was investigated to present the feasibility to use POSS molecule as a coating material on the surface of the hydrophilic inorganic glass. In addition, Poly(ethylene terephthalate) polymer matrix composites incorporating Pglass was studied to present the benefits of the Pglass with …
Effect Of Network Structure On Free Volume And Gas Transport Properties Of Thiol-Ene And Epoxy-Amine Networks, Ramesh Krishnan Ramakrishnan
Effect Of Network Structure On Free Volume And Gas Transport Properties Of Thiol-Ene And Epoxy-Amine Networks, Ramesh Krishnan Ramakrishnan
Dissertations
Network parameters such as cross-link density or intermolecular interactions were used as effective parameters to control polymer chain packing or free volume and thereby control the mass transport properties of networks.
A series of polyethylene glycol (PEG) based thiol-ene elastomeric networks having a broad range of molecular weight between cross-links, Mc, (inverse of cross-link density) was prepared. The specific volume of the networks was studied as a function of temperature and pressure using high pressure dilatometry, and the obtained PVT data was fit using Simha-Somcynsky equation of state (S-S eos) analysis. Fractional free volume, quantified through S-S eos …