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An analysis of the delay-dependent HIV-1 protease inhibitor model

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International Journal of Biomathematics 2018年第3期11卷 1-22页

作者： m. Divya m. Pitchaimani Ramanujan Institute for Advanced Study in mathematics University of madras Tarnilnadu 600005 India

In this paper, we have studied about the sensitivity analysis of the human immunodeficiency virus （HIV） protease inhibitor （PI） model and estimated the length of the delay. We have fabricated an HIV PI model accompanied with humoral immunity. Stability analysis of the constructed model about its steady states has been deliberated. We have evaluated some numerical simulations for PI model with humoral immunity by using the existing patient data.

关键词： HIV dynamics treatment delay differential equations sensitivity stability

Spherical Logistic Distribution

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Communications in mathematics and Statistics 2020年第2期8卷 151-166页

作者： m.moghimbeygi m.Golalizadeh Department of Statistics Tarbiat Modares UniversityTehranIran

some of the spherical distributions can be constructed through proper transformation of the densities on *** the logistic density on the Euclidean space has similar behavior to the normal distribution,it is of interest to extend it for spherical *** this paper,we introduce spherical logistic distribution on the unit sphere and then study relevant statistical inferences including parameters estimation through method of moments and maximum likelihood *** is shown that the spherical logistic distribution is a multimodal distribution with the marginal logistic density *** density has rotational symmetry property and this plays a key role to drive some important results related to first two *** investigate the proposed density in more details,some simulation studies along with analyzing real-life data are also considered.

关键词： Bessel function Logistic density Bimodality Spherical distribution Rotational symmetry

Superconducting State Parameters of NbxTaymoz Superconductors

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Chinese Physics Letters 2010年第2期27卷 195-198页

作者： Aditya m. Vora Humanities and Social Science Department S. T. B. S. College of Diploma Engineering Opp. Spinning Mill Varachha Road Surat 395 006 Gujarat India

We present screening dependence theoretical investigations of the superconducting state parameters, i.e. electron-phonon coupling strength λ, Coulomb pseudopotential μ＊, transition temperature TC, isotope effect exponent α, and effective interaction strength N0V, of some BmG superconductors, namely Nb0.45Ta0.45mo0.10, Nb0.30Ta0.40mo0.30, Nb0.40Ta0.30mo0.30, Nb0.30Ta0.30mo0.40 and Nb0.15Ta0.15mo0.70 by employing the well-known empty core model potential of Ashcroft for the first time. Five local field correction functions proposed by Hartree, Taylor, Ichimaru-Utsumi, Farid et al. and Sarkar et al. are used in the present investigation to study the screening influence on the aforesaid superconducting properties. The transition temperature TC obtained from the H-local field correction function is found to be in an excellent agreement with the available theoretical data. Also, the present results are found to be in qualitative agreement with other such earlier reported data, which confirms the superconducting phase in the superconductors.

关键词： Superconductivity

Borescopic particle image velocimetry in bubbling gas-solid fluidized beds

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Particuology 2019年第2期17卷 66-75页

作者： m. Banaei R. Dellaert N.G. Deen J.A.m. Kuipers m. van Sint Annaland multiphase Reactors Group Department of Chemical Engineering & Chemistry Eindhoven University of Technology P.O. Box 513 5600 MB Eindhoven The Netherlands Dutch Polymer Institute (DPI) P.O. Box 902 5600 AX Eindhoven The Netherlands multiphase and Reactive Flows Group. Department of mechanical Engineering Eindhoven University of Technology P.O. Box 513 5600 MB Eindhoven The Netherlands

In this work, the borescopic particle image velocimetry (BPIV) technique was applied to a bubbling gas-solid fluidized bed, and the results were compared with published positron emission particle tracking (PEPT) measurement data. Before performing the experiments, the sensitivity of the BPIV results to the illumination power, light reflectivity of the particles, and location of the borescope was also investigated. The BPIV and PEPT results were in fair agreement;however, some discrepancies were *** difference between the two sets of results were mainly caused by the intrusiveness of BPIV, the fact that the local solids volume fraction was not accounted for in the BPIV analysis, and the intrinsic differences of these two methods. Therefore, measurement of the local solids volume fraction with the borescope is highly recommended for further development of the BPIV method, which will also enable measureme nt of the local solids mass fluxes in side dense gas-solid fluidized beds.

关键词： Borescopic particle image velocimetry Gas-solid bubbling fluidized bed Solid velocity profile Experimental investigation Hydrodynamics

Double sampling derivatives and truncation error estimates

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Applied mathematics(A Journal of Chinese Universities) 2018年第2期33卷 209-224页

作者： Rashad m.Asharabi Aisha m.Al-Hayzea Department of mathematics College of Arts and Sciences Najran University

This paper investigates double sampling series derivatives for bivariate functions defined on R2 that are in the Bernstein space. For this sampling series, we estimate some of the pointwise and uniform bounds when the function satisfies some decay conditions. The truncated series of this formula allow us to approximate any order of partial derivatives for function from Bernstein space using only a finite number of samples from the function itself. This sampling formula will be useful in the approximation theory and its applications, especially after having the truncation error well-established. Examples with tables and figures are given at the end of the paper to illustrate the advantages of this formula.

关键词： double sampling series truncation error bounds convergence rate

Spectral Solutions of Linear and Nonlinear BVPs Using Certain Jacobi Polynomials Generalizing Third- and Fourth-Kinds of Chebyshev Polynomials

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Computer modeling in Engineering & Sciences 2021年第3期126卷 955-989页

作者： W.m.Abd-Elhameed Asmaa m.Alkenedri Department of mathematics Faculty of ScienceCairo UniversityGizaEgypt Department of mathematics College of ScienceUniversity of JeddahJeddahSaudi Arabia

This paper is dedicated to implementing and presenting numerical algorithms for solving some linear and nonlinear even-order two-point boundary value *** this purpose,we establish new explicit formulas for the high-order derivatives of certain two classes of Jacobi polynomials in terms of their corresponding Jacobi *** two classes generalize the two celebrated non-symmetric classes of polynomials,namely,Chebyshev polynomials of third-and *** idea of the derivation of such formulas is essentially based on making use of the power series representations and inversion formulas of these classes of *** derived formulas serve in converting the even-order linear differential equations with their boundary conditions into linear systems that can be efficiently ***,and based on the first-order derivatives formula of certain Jacobi polynomials,the operational matrix of derivatives is extracted and employed to present another algorithm to treat both linear and nonlinear two-point boundary value problems based on the application of the collocation *** analysis of the proposed expansions is *** numerical examples are included to demonstrate the validity and applicability of the proposed algorithms.

关键词： Jacobi polynomials high-order boundary value problems Galerkin method collocation method connection problem convergence analysis

some OSCILLATION CRITERIA FOR SECOND ORDER NONLINEAR FUNCTIONAL ORDINARY DIFFERENTIAL EQUATIONS

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Acta mathematica Scientia 2007年第3期27卷 602-610页

作者： E.m.E.Zayed m.A.El-moneam mathematics Department Faculty of ScienceZagazig UniversityZagazigEgypt

The main objective of this article is to study the oscillatory behavior of the solutions of the following nonlinear functional differential equations（a（t）x＇（t））＇＋δ1p（t）x＇（t）＋δ2q（t）f（x（g（t））） = 0,for 0 ≤ to≤ t, where 51 = ：El and δ±1. The functions p,q,g ： [t0, ∞） → R, f ： R → are continuous, a（t）〉 0,p（t） ≥0,q（t）〉 0 for t ≥ to,lirn g（t） = ∞, and q is not identically zero on any subinterval of [to, ∞）. moreover, the functions q（t）, g（t）, and a（t） are continuously differentiable.

关键词： Oscillatory and nonoscillatory solutions nonlinear functional differential equations

Optimization of hole-boring radiation pressure acceleration of ion beams for fusion ignition

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matter and Radiation at Extremes 2018年第1期3卷 28-39页

作者： S.m.Weng Z.m.Sheng m.murakami m.Chen m.Liu H.C.Wang T.Yuan J.Zhang Key Laboratory for Laser Plasmas(moE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUK Institute of Laser Engineering Osaka UniversityOsaka 565-0871Japan

In contrast to ion beams produced by conventional accelerators,ion beams accelerated by ultrashort intense laser pulses have advantages of ultrashort bunch duration and ultrahigh density,which are achieved in compact ***,it is still challenging to simultaneously enhance their quality and yield for practical applications such as fast ion ignition of inertial confinement *** with other mechanisms of laser-driven ion acceleration,the hole-boring radiation pressure acceleration has a special advantage in generating high-fluence ion beams suitable for the creation of high energy density state of *** this paper,we present a review on some theoretical and numerical studies of the hole-boring radiation pressure *** we discuss the typical field structure associated with this mechanism,its intrinsic feature of oscillations,and the underling *** we will review some recently proposed schemes to enhance the beam quality and the efficiency in the hole-boring radiation pressure acceleration,such as matching laser intensity profile with target density profile,and using two-ion-species *** on this,we propose an integrated scheme for efficient high-quality hole-boring radiation pressure acceleration,in which the longitudinal density profile of a composite target as well as the laser transverse intensity profile are tailored according to the matching condition.

关键词： Laser-driven ion acceleration Radiation pressure acceleration Fast ignition Inertial confinement fusion High energy density Hole boring

Effect of Al powder and silica sol on the structure and mechanical properties of Al_2O_3-ZrO_2 foams

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Acta metallurgica Sinica(English Letters) 2010年第4期23卷 241-247页

作者： H.Sharifi m.Divandari A.Khavandi m.H.Idris School of materials and metallurgical Engineering Iran University of Science and Technology Department of material Engineering Faculty of Mechanical EngineeringUniversti Teknologi Malaysia

Polymeric sponge replication method is one of the common ways for ceramic foam production. The existence of central triangular voids in the struts results in a decrease of mechanical properties limiting their applications. To remove this defect, some additives consisting of Al powder particles and silica sol are added to ceramic slurries consisting of Al2O3 and ZrO2 （partially stabilized zirconia）. With increasing temperature for pyrolyzing and sintering of raw materials, first the Al powder and then the glass phase which consisted of melted Al2O3, ZrO2 and SiO2 was soaked into hollow struts. SEm investigations showed that the center of foam struts were free of hollows. XRD considerations depicted that a ZrO2 phase with tetragonal crystallographic structure is present in the produced foam which could be the reason of improved toughness and mechanical properties. Compressive strength of foams increased significantly due to the decrease of closed porosity. The Weibull statistical study showed remarkable increasing of the Weibull module and its value for foams with 10, 20 and 30 ppi was 5.91, 6.06 and 6.53 respectively.

关键词： Ceramic foam Processing Strut structure Al2O3-ZrO2 Weibull modulus