Novel Model of HIV-AIDS Epidemics with Vaccination | Chapter 3 | Research and Applications Towards Mathematics and Computer Science Vol. 8

The principles of the HIV-AIDS epidemics and the relations of susceptible, HIV infected, AIDS, and immunized subpopulation will be established. We would like to develop a general mathematical modeling for HIV - AIDS with Vaccination to understand the spread of the aids virus and to predict the number of infected individuals during a certain period in a population. Further we expand the research to special cases with no vaccinations. We will investigate the model in special case when the removal subset of the population is empty, or there is no recovery in this epidemic. We also can consider the total infected number is equal to the sum of the HIV infected and the number of AIDS infected. As a result, we can use SIR Monte Carlo simulation method in SIR case to verify the Validity of the HIV-AIDS model.

Author(s) Details:

Reza R. Ahangar,
Mathematics Department, Texas A & M University Kingsville, United States.

Please see the link here: https://stm.bookpi.org/RATMCS-V8/article/view/13070

Microspheres Transport in a Viscous Fluid Induced by an External Oscillator Field | Chapter 2 | Research and Applications Towards Mathematics and Computer Science Vol. 8

The movement of nano/micro-particles in a viscous media has recently received attention due to its diverse applications in applied science and engineering. In the current chapter, the interactions of a two-solid microspheres system in Stokes ow at low Reynolds number power by an external oscillator field is studied analytically. A conducting microsphere moves under the action of an external field, and the other nonconducting sphere moves due to the induced ow oscillation generated by the motion of the active sphere. The governing equation in the vector form for the two-sphere system is formulated and solved asymptotically using the two-timing method. For illustrations, by applying a simple oscillatory external FIeld, the results show that no collisions occur between two spheres as the system moves in a circular motion with a fixed separation distance, and that its trajectory was found to be inversely proportional to the frequency of the external field.

Author(s) Details:

M. M. Al-Hatmi,
Department of Basic Science, College of Applied and Health Sciences, A' Sharqiyah University, Oman.

Please see the link here: https://stm.bookpi.org/RATMCS-V8/article/view/13069

Cross-Multiplication Method in Computing Determinants of n ×n Matrices | Chapter 1 | Research and Applications Towards Mathematics and Computer Science Vol. 8

The determinant is one of the interesting and essential topics in matrix algebra for its applications and representation utility. In this paper, a novel, straightforward, and symmetry-based technique for manually computing the determinant of any n X n matrix is developed. The method is derived from Dodgson’s condensation method which involves the computation of determinants of four adjacent entries within the interior submatrix of a given matrix. By strategically applying elementary row (column) operations and the definition and properties of determinants, the new method proceeds without assigning an interior submatrix by fixing the nonzero first entries of two adjacent rows as pivot elements in computing the determinants of succeeding four entries. The process suggests a symmetric butterfly movement coined cross-multiplication, yields a more streamlined algorithm that is generalized through formulas, and employs a smaller number of operations and succeeding matrices than the existing methods.

Author(s) Details:

Judel Villas Protacio,
College of Education, Arts and Sciences, Capiz State University, Pontevedra, Capiz 5802, Philippines

Please see the link here: https://stm.bookpi.org/RATMCS-V8/article/view/13067

Study about Effective Metal Shield(s) of High Voltage Distribution Cable Lines | Chapter 9 | Theory and Applications of Engineering Research Vol. 4

This chapter introduces a certain improvement, from the standpoint of applicability the methodology that enables the analysis of complex electric circuits with an arbitrarily large number of inductively coupled elements whose relevant data are uncertain or completely unknown. In practice, such circuits are spontaneously formed by HV and EHV cable lines that pass through urban and/or suburban areas. The pulsating magnetic field created by currents in the phase conductor(s) of these lines induces voltages and currents in their metal shields and all surrounding metal installations typical for these areas. Each of the induced currents creates its own magnetic field which acts in such a way that reduces all other induced currents including currents in the phase conductor(s) of the inducing cable line. The problem arises because of the fact that these installations are, as a rule, situated under the surface of the ground, and because of that, their constructive characteristics and spatial positions are the most frequently uncertain or completely unknown. In many cases, even the total number of these installations is unknown. Because of that, the problem of determining the effects of the interaction between the mentioned cable lines and surrounding metal installations was for a long time considered practically unsolvable. Only recently was developed the methodology that is based on the test measurements of currents appearing in two phase conductors of the considered cable line during a simulated ground fault in the supplied substation. Their values are utilized to compensate for the deficiency of all relevant but unknown data concerning the surrounding metal installations. It was done by introducing an equivalent cable shield substituting, from the standpoint of inductive influence, all surrounding metal installations. Here is shown that this equivalent shield is determined in such a way that it becomes identical to the actual cable line shield but only with a changed value of its longitudinal resistance. When this parameter is determined for single-core cable(s) belonging to a certain cable line it becomes possible to determine the actual reduction factor, inductive influence during a ground fault as well as during normal operation, and sequence impedance of the considered cable line by using a standard and well-known calculation procedures.

Author(s) Details:

Ljubivoje M. Popovic,
J. P. Elektrodistribucija-Beograd, Elektroprivreda Srbije, Masarikova 1-3, 11000 Beograd, Serbia.

Please see the link here: https://stm.bookpi.org/TAER-V4/article/view/13133

Enhancing Load Frequency Control in a Four-Area Power System Network with an Optimal ANN Controller | Chapter 8 | Theory and Applications of Engineering Research Vol. 4

This research describes an optimal artificial neural network (ANN) controller for load frequency control (LFC) of a four-area interconnected power system with non-linearity. Automatic load frequency control is the main area of concern in the operation of an interconnected power system. A feed forward neural network with multi-layers and Bayesian regularization backpropagation (BRB) training function is used. This controller is designed on the basis of optimal control theory to overcome the problem of load frequency control as load changes in the power system. The system comprises of transfer function models of two thermal units, one nuclear unit and one hydro unit. To accommodate for non-linearity, the model integrates the generation rate constraint (GRC) of distinct units. The typical system parameters obtained from IEEE press power engineering series and EPRI books. The network training is based on the data collected from the optimal controller for different perturbations or step load changes. As the inputs are applied to the network, the outputs are compared to the target values, and the supervised learning rule is used. The robustness, effectiveness, and performance of the proposed optimal ANN controller for a step load change and random load change in the system is simulated through using MATLAB-Simulink. The time response characteristics are compared with that obtained from the proportional, integral and derivative (PID) controller and non-linear autoregressive-moving average (NARMA-L2) controller. The results show that the algorithm developed for proposed controller has a superiority in accuracy as compared to other two controllers. The proposed controller performs satisfactorily under random step load changes and thus desirable dynamic control of the system is achieved.

Author(s) Details:

Basavarajappa Sokke Rameshappa,
Department of Electrical and Electronics Engineering, Bapuji Institute of Engineering and Technology, Davanagere Visvesvaraya Technological University, Belagavi, Karnataka, India.

Nagaraj Mudakapla Shadaksharappa,
Department of Electrical and Electronics Engineering, Bapuji Institute of Engineering and Technology, Davanagere Visvesvaraya Technological University, Belagavi, Karnataka, India.

Please see the link here: https://stm.bookpi.org/TAER-V4/article/view/13102

Exploring Spray Nozzle Performance through Computational Fluid Dynamics with Pulse-Width Modulation | Chapter 7 | Theory and Applications of Engineering Research Vol. 4

This study investigates the effect frequency has on the spray distribution characteristics by determining whether CFD can be used to study pulsed spray nozzles and simulate a spray nozzle that is pulsed at various frequencies. Computational fluid dynamics (CFD) is a useful tool used by engineers in many industries to study fluid flow. A relatively new industry to adopt the use of CFD is the agricultural industry. A spray nozzle commonly used in agricultural spraying, the Teejet 110-degree nozzle , was simulated. A method was developed to pulse the spray. A user-defined function was used to define the velocity at the inlet of the nozzle to pulse the spray. The domain was then extended to allow the examination of a slice 20 inches below the nozzle. The simulation results were compared to experimental results collected from a sprayer testbed. The effect of frequency was then investigated by changing the frequency of the pulses. Results from these studies show that a user-defined function can be used to pulse the spray. Spray nozzles can be modeled using CFD, but the accuracy of the findings is highly dependent on the available computing power. Increasing the pulse frequency produces a more concentrated spray in the direction of the spray plume's center. The simulations were carried out using a commercial code (CD-Adapco, 2019). Further investigation is necessary to acquire that lower frequencies may provide better results. The lower frequencies provide a more uniform spray distribution which would provide more even coverage during the spraying process.

Author(s) Details:

Zachary Chapman,
Mechanical Engineering Department, South Dakota State University, Brookings, SD, USA.

Jeffrey Doom,
Mechanical Engineering Department, South Dakota State University, Brookings, SD, USA.

Please see the link here: https://stm.bookpi.org/TAER-V4/article/view/13101

Computational Fluid Dynamics Studies on the Impact of Viscosity and flow rate of Dope Solution in Hollow Fiber Ultra Filtration Membrane Formation | Chapter 6 | Theory and Applications of Engineering Research Vol. 4

The performance of the polymeric membranes depends on morphology and its strength. The pressure-driven membrane separation process required good structural strength and desired flux. But these parameters depend on the formation of the right size pores, the number of pores & their distribution, and even wall thickness in surface and cross-sectional morphologies of the membrane. The desired values of the above decide the structural stability and permeate flux of hollow fibre membrane(HFM). Obtaining the desired membrane morphology yields the preferred strength and performance. In general, the characteristics of membranes derived from the flow rate of the dope solution, the shear rate, the composition of dope solutions, and the mass flux rate between solvent and non-solvent at the coagulant bath during the spinning process. So, a steady state simulation performed using the Computational Fluid Dynamics (CFD) tool to understand the fluid flow behavior inside the angular spinneret and the results correlated with the physio-structural parameters such as strength, morphology, burst pressure of the hollow fiber Ultra Filtration (UF) membrane and its formation. The study on the flow behavior of dope solution inside the spinneret carried by various the power-law index value (0.3 < n <0.7) and the dope solution flow rate (0.1< Q <1.2 mL/min). The flow profiles at the exit of 75o angular spinneret gave the delightful result of why the fiber membrane unable to withstand the high-pressure application. Also, it is exbound that the shear induced flow rate is struggle to drive some power-law index fluids and resulted in bulk flow at some spot of exit of the spinneret and leaves the hollow fiber membrane to form uneven wall thickness. The dope flow rate and the power-law index values need to be optimized to understand the formation of UF membrane morphology.

Author(s) Details:

Suresh K.,
Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, India.

Selvam K.,
Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, India.

Karunanithi B.,
Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamil Nadu, India.

Please see the link here: https://stm.bookpi.org/TAER-V4/article/view/13100