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Influence of Mathematics in The Desertion of Higher Education
Get PDFIn the present work the different models of university desertion are analyzed, identifying the factors that have influence in the continuation of the studies of the students. These factors are essentials to defining what will be understood by university desertion and to elaborate the profile of the deserter. In the case of the Universidad de Las Américas (Quito, Ecuador), the main factors that influence the desertion are corroborated with those that have been established according to the existing bibliography and a descriptive study of these data is carried out, in order to elaborate indicators that allow us to predict the behavior of the student population with a higher risk of dropping out. An analysis is made relating the area of Mathematics and the desertion, seeing how this area influences the possibility of a student dropping out.
 
A Parametric Approach for Solving Interval–Valued fractional Continuous Static Games
Get PDFThe aim of this paper is to show that a parametric approach can be used to solve fractional continuous static games with interval-valued in the objective function and in the constraints. In this game, cooperation among all the players is possible, and each player helps the others up to the point of disadvantage to himself, so we use the Pareto-minimal solution concept to solve this type of game. The Dinkelbach method is used to transform fractional continuous static games into non- fractional continuous static games. Moreover, an algorithm with the corresponding flowchart to explain the suggested approach is introduced. Finally, a numerical example to illustrate the algorithm’s steps is given
Almost Paracontact 3-Submersions
Get PDFIn this paper, we discuss some geometric properties of Riemannian submersions whose total space is an almost paracontact manifold with 3-structure. The study is focused on the transference of structures, the geometry of the fibres and sectional curvature tensor
Spectroscopy and Conductivity Studies of Polyvinyl Alcohol (PVA)/Polypyrrol (Ppy) Nanocomposite with Various Chloride Metals to Improved Properties of the Polymers
Get PDFPolyvinyl alcohol- polypyrrole (PVA-PPy) nanocomposites with metal chlorides (FeCl3, NiCl2, CuCl2 and ZnCl2) have been synthesized by chemical oxidative polymerization method. These synthesized nanocomposites are characterized by using FTIR, X-ray diffraction, Transition electron microscope (TEM) and Conductivity measurement. TEM exhibit that all of the composites have uniform sizes and morphologies. The diameter of PVA/PPy nanocompsite is 58nm when the metals added to the PVA/PPy the diameters becomes smaller. The variation of electrical conductivity (log ?) with 1000/T for PVA/PPy nanocomposite with metal chlorides revealed that the increase in conductivity s at temperature (393K) with added metals can be attributed to the creation of induced charge carriers in PVA/PPy matri
Study on MHD Cylindrical Couette Flow and Rheological Properties of Some Magnetic Suspensions
Get PDFThe study of magnetic suspensions (MS) and magnetic field effects on their rheological properties is of evident practical importance due to its ability to orient and change their physical properties, especially their viscosity, by magnetic fields. This research presents the effect of a uniform magnetic field on the flow of MS in the annular region between two concentric cylinders. The motion of the fluid is due to the rotation of the inner cylinder with a constant angular velocity. An exact solution of the governing equations is obtained in the form of modified Bessel functions of the first and second kinds. The torque, which must be applied to the inner cylinder in order to maintain the rotation, is also calculated. The results show that as the magnetic parameter increases, the velocity profile decreases, while the torque increases due to the effect of magnetic force against the flow direction.
In order to model the magnetoviscous effects, experiments were performed for different shear rates and different magnetic field strengths by using specially designed rheometers. The studied samples are iron oxide-water-glycerol system, ferrofluid nanoparticles, MAG DX biocompatible ferrofluid. The theoretical analysis is based on Giesekus model for MS. This model gives more accurate results and takes into account the effects of viscoelastic shear thinning characteristics. It is found that a magnetic field increases the viscosity of all suspensions under consideration. Finally, new proposed correlation for the viscosity of MS as a function of both shear rate and magnetic field has been suggested
Structural And Vibrational Studies on Isomers of Antiviral Ribavirin Drug in Gas and Aqueous Environmental by Using The SQM Approach
Get PDFFive stable isomers of antiviral ribavirin agent were theoretically determined in gas and aqueous solution by using the hybrid B3LYP/6-31G* method. Here, the solvent effects were studied with the self consistent reaction field (SCRF) methodology employing the polarized continuum (PCM) and the universal solvation model (SM). Structural, electronic and topological properties were reported for all isomers while the vibrational analyses were performed only for those two polymorphic structures experimentally observed in the solid phase by X-ray diffraction. Calculations have evidenced that C2 correspond to the polymorphic V1 structure while C5 to the polymorphic V2 structure. The high dipole moment values predicted for C2 and C5 in both media could probably explain their presences in the solid. Experimental available IR and Raman spectra of ribavirin in the solid state and normal internal coordinates were employed together with the scaled quantum mechanical force field (SQMFF) approach to perform the complete vibrational assignments in both media. Here, the 81 vibration modes expected for C2 and C5 in both media were completely assigned. The frontier orbitals studies reveal that C5 is the less reactive in both media. Here, the gap value observed for C5 is in agreement with the value recently reported for ribavirin by using B3LYP/6-311++G** calculations
Exact Solution of a Linear Difference Equation in a Finite Number of Steps
Get PDFAn exact solution of a linear difference equation in a finite number of steps has been obtained. This refutes the conventional wisdom that a simple iterative method for solving a system of linear algebraic equations is approximate. The nilpotency of the iteration matrix is the necessary and sufficient condition for getting an exact solution. The examples of iterative equations providing an exact solution to the simplest algebraic system are presented
A Solution Algorithm for Interval Transportation Problems via Time-Cost Tradeoff
Get PDFIn this paper, an algorithm for solving interval time-cost tradeoff transportation problemsis presented. In this problem, all the demands are defined as intervalto determine more realistic duration and cost. Mathematical methods can be used to convert the time-cost tradeoff problems to linear programming, integer programming, dynamic programming, goal programming or multi-objective linear programming problems for determining the optimum duration and cost. Using this approach, the algorithm is developed converting interval time-cost tradeoff transportation problem to the linear programming problem by taking into consideration of decision maker (DM)
Some Generalizations of Green’s Relations in Rings and Modules
Get PDFIn semigroups theory Green’s relations, introduced by J. Green, are a very important and useful tool for developing the semigroup theory. They characterise the element of a semigroup or a ring in terms of the principal ideals they generate. In contrast to early semigroup theory , where, as we have seen, ideas from ring’s were applied to semigroups, Green’s relation’s have also been applied to ring’s (Hollings, 2014). In ring theory Green’s relation’s are introduced by (Petro,2002) In this paper at first we generalize Green’s relations in rings. After this we notice that there exist an one to one correspondence between the ideals of a ring and this type of new relations we introduced.Then we compare them with Green’s relations in rings. At last we define some new relations in module theory, which mimic Green’s relations in rings, as an attempt to get tools in studying modules. 
Green's Relations in Rings and Completely Simple Rings
Get PDFIn this paper we prove that which of Green's relations and in rings preserve the minimality of quasi-ideal. By this it is possible to show the structure of the classes generated by the above relations which have a minimal quasi ideal. For the completely simple rings we show that they are generated by the union of zero with a -class. Also we emphasize that a completely simple ring coincides with the union of zero with a -class if and only if it is a division ring