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Approximate analytical solutions and mean energies of stationary schrodinger equation for general molecular potential

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Chinese Physics B 2021年第7期30卷 116-131页

作者： eyube e s Rawen B O Ibrahim N Department of Physics School of Physical SciencesModibbo Adama University of TechnologyP M B 2076 YolaAdamawa StateNigeria Directorate of Basic and Remedial studies Abubakar Tafawa Balewa University(ATBU)P M B 750001BauchiBauchi StateNigeria Department of Physics Faculty of ScienceP M B 1069MaiduguriBorno StateNigeria

The schrodinger equation is solved with general molecular potential via the improved quantization *** for bound state energy eigenvalues,radial eigenfunctions,mean kinetic energy,and potential energy are obtained in compact *** modeling the centrifugal term of the effective potential,a Pekeris-like approximation scheme is ***,we use the Hellmann–Feynman theorem to derive the relation for expectation *** state energy eigenvalues,wave functions and meanenergies of Woods–saxon potential,Morse potential,Mobius squared and Tietz–Hua oscillators are deduced from the general molecular *** addition,we use our equations to compute the bound state energy eigenvalues and expectation values for four diatomic molecules viz.H_(2),CO,HF,and O_(2).Results obtained are in perfect agreement with the data available from the literature for the potentials and *** also show that as the vibrational quantum number increases,the mean kinetic energy for the system in a Tietz–Hua potential increases slowly to a threshold value and then *** in a Morse potential,the mean kinetic energy increases linearly with vibrational quantum number increasing.

关键词： general molecular potential schrodinger equation improved quantization rule

exact solutions of Kolmogorov-Petrovskii-Piskunov equation Using the Modified simple equation Method

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Acta Mathematicae Applicatae sinica 2014年第3期30卷 749-754页

作者： e.M.e.Zayed s.A.Hoda Ibrahim Mathematics Department Faculty of ScienceZagazig University

The modified simple equation method is employed to find the exact solutions of the nonlinear Kolmogorov-Petrovskii-Piskunov （KPP） equation. When certain parameters of the equations are chosen to be special values, the solitary wave solutions are derived from the exact solutions. It is shown that the modified simple equation method provides an effective and powerful mathematical tool for solving nonlinear evolution equations in mathematical physics.

关键词： modified simple equation method Kolmogorov-Petrovskii-Piskunov equation exact solutions solitary wave solutions

Numerical investigation of Reynolds number and scaling effects in microchannels flows

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Journal of Hydrodynamics 2017年第4期29卷 647-658页

作者： s.A.si salah e.G.Filali s.Djellouli Faculty of Mechanical and Process engineering Houari Boumedienne University

Compared with conventional channels, experiments of microchannel often exhibit some controversial findings and sometimes even opposite trends, most notably the effects of the Reynolds number and the scaled channel height on the Poiseuille number. The experimental method has still been constrained by two key facts, firstly the current ability to machine microstructures and secondly the limitation of measurement of parameters related to the Poiseuille number. As a consequence, numerical method was adopted in this study in order to analyze a flow in two-dimensional rectangular microchannels using water as working fluid. Results are obtained by the solution of the steady laminar incompressible Navier-stokes equations using control volume finite element method（CVFeM） without pressure correction. The computation was made for channel height ranging from 50 ？m to 4.58 ？m and Reynolds number varying from 0.4 to 1 600. The effect of Reynolds number and channel heights on flow characteristics was investigated. The results showed that the Poiseuille numbers agree fairly well with the experimental measurements proving that there is no scale effect at small channel height. This scaling effect has been confirmed by two additional simulations being carried out at channel heights of 2.5 ？m and 0.5 ？m, respectively and the range of Reynolds number was extended from 0.01 up to 1 600. This study confirm that the conventional analysis approach can be employed with confidence for predicting flow behavior in microchannels when coupled with carefully matched entrance and boundary conditions in the dimensional range considered here.

关键词： Rectangular microchannel Poiseuille number control volume finite element method(CVFeM) laminar flow minichannels

Mid/far-infrared photo-detectors based on graphene asymmetric quantum wells

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Chinese Physics B 2016年第9期25卷 573-580页

作者： e Ben salem R Chaabani s Jaziri Institut Preparatoire aux etudes d'Ingenieurs de Tunis 2 Rue Jawaher Lel Nahrou Monfleury 1089 Tunisie Laboratoire de Physique de la Matiere Condensee Departement de Physique Faculte des Sciences de Tunis Campus Universitaire 2092 Tunisie Departement de Physique Faculte des Sciences de Bizerte Jarzouna 7021 Bizerte

We conducted a theoretical study on the electronic properties of a single-layer graphene asymmetric quantum *** of energy levels is limited by electron–hole conversion at the barrier interfaces and free-electron ***–hole conversion at the barrier interfaces can be controlled by introducing an asymmetry between barriers and taking into account the effect of the interactions of the graphene sheet with the *** interaction with the substrate induces an effective mass to carriers,allowing observation of Fabry–P′erot resonances under normal incidence and extinction of Klein *** asymmetry,between barriers creates a transmission gap between confined states and free-electron continuum,allowing the large graphene asymmetric quantum well to be exploited as a photo-detector operating at mid-and far-infrared frequency regimes.

关键词： graphene quantum wells reflection coefficient photo-detector

Power Prediction of VLsI Circuits Using Machine Learning

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Computers, Materials & Continua 2023年第1期74卷 2161-2177页

作者： e.Poovannan s.Karthik Department of eCe College of Engineering and TechnologySRM Institute of Science and TechnologyVadapalani CampusChennai600026TNIndia

The difference between circuit design stage and time requirements has broadened with the increasing complexity of the circuit.A big database is needed to undertake important analytical work like statistical method,heat research,and IR-drop research that results in extended running *** unit focuses on the assessment of test *** of the enormous number of successful designs for currentmodels and the unnecessary time required for every test,maximum energy ratings with all tests cannot be ***,test safety is important for producing trustworthy findings to avoid loss of output and harm to the ***,effective power assessment is only possible in a limited sample of pre-selected ***,a key objective is to find the experiments that might give the worst situations again for testing *** offers a machine-based circuit power estimation(MLCPe)system for the selection of *** distinct techniques of predicting are ***,to find testings with power dissipation,it forecasts the behavior of ***,the changemovement and energy data are linked to the semiconductor design,identifying small problem *** types of algorithms are *** particular,the methods *** findings show great accuracy and efficiency in *** enables such methods suitable for selecting the worst scenario.

关键词： Power estimation Machine learning circuit simulation VLsI implementation

Maximal Abelian subalgebras of the Hyperfinite Factor,entropy and ergodic Theory

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Acta Mathematica sinica,english series 2003年第3期19卷 599-604页

作者： s.NesHVeYeV e.sTORMeR DepartmentofMathematics UniversityofOsloP.O.Box1053BlindernN-0316OsloNonway

Given a free ergodic action of a discrete abelian group G on a measure space (X, 7), the crossed product LX (X, 7)p G contains two distinguished maximal abelian subalgebras. We discuss what kind of information about t... 详细信息

关键词： Hyperfinite facter Maximal abelian subalgebra Dynamical system entropy

AUTOMATIC AUGMeNTeD GALeRKIN ALGORITHMs FOR FReDHOLM INTeGRAL eQUATIONs OF THe FIRsT KIND

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Acta Mathematica scientia 1997年第1期17卷 69-84页

作者： s.Abbasbandy e.Babolian Institute of Mathematics Teacher Training University Tehran 15614 IRAN

In recent papers, Babolian & Delves [2] and Belward[3] described a Chebyshev series method for the solution of first kind integral equations. The expansion coefficients of the solution are determined as the solution of a mathematical programming *** method involves two regularization parameters, Cf and r, but values assigned to these parameters are heuristic in nature. essah & Delves[7] described an algorithm for setting these parameters automatically, but it has some difficulties. In this paper we describe three iterative algorithms for computing these parameters for singular and non-singular first kind integral equations. We give also error estimates which are cheap to compute. Finally, we give a number of numerical examples showing that these algorithms work well in practice.

关键词： Fredholm integral equations Galerkin method Regularization parameters error estimation Ill-Posed problems Product of chebyshev series

To optimize splice joint between different PCF-based devices and sMF transmission medium

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Chinese Optics Letters 2009年第3期7卷 246-250页

作者： Faramarz e.seraji s.Farsinezhad Optical Communication Group Iran Telecom Research Center electrical engineering Department Semnan University

An analysis of splice loss between photonic crystal fibers （PCFs） and conventional single-mode fibers （sMFs） is presented at bending and straight conditions, by using scalar effective index method （seIM）, vectorial effective index method （VeIM）, and finite-difference frequency domain （FDFD） methods. It is shown that when there is a slight bending at the vicinity of splice joint, the spot size increases sharply at higher frequencies. On the basis of the obtained results, a mechanism to optimize the splice loss between PCFs and conventional sMFs, both with any geometry, is suggested. The results can be utilized for PCF- based devices to be jointed to sMF as a transmission medium.

关键词： Frequency domain analysis Photonic crystal fibers

Use of virtual reality in underground roof fall hazard assessment and risk mitigation

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International Journal of Mining science and Technology 2019年第4期29卷 603-607页

作者： e.Isleyen H.s.Duzgun Department of Mining engineering Colorado School of Mines

Virtual reality(VR)simulations are some of the alternative practice environments for safety *** gain experience under the most realistic conditions without being exposed to any real *** reality also serves as a tool to expedite the decision-making process where quick decisions and actions are necessities for a safe *** example of such a situation in underground mines is the failure risks in a tunnel face after *** support systems must be installed based on the stand-up time to ensure the safe access of personnel and equipment to the working ***,a competent person inspects the area to identify risks and determines the required support ***,training of a competent person requires large amount of time and *** study presents virtual reality simulations developed for improving the assessment of the roof fall hazards and taking necessary measures for mitigating the risk related to roof *** virtual reality simulation involves decision-making tasks for a particular scenario in which participants can experience creating a safe working environment in a timely ***,they are asked to identify the potential hazard in a tunnel after blasting,namely,rock fall,wedge failure or groundwater *** the hazard identification is successful,participants are requested to install rock bolts as a safety measure by selecting the bolt pattern(*** length and spacing).Finally,participants evaluate the roof fall hazard by viewing displacements around the opening,before and after the support *** study illustrates the benefits of VR in safety training as well as enhancing the decision-making process to enhance safety.

关键词： Virtual reality Hazard assessment Tunneling