The article emphasizes that 3D stochastic positive linear system with delays is asymptotically stable and depends on the sum of the system matrices and at the same time independent on the values and numbers of the delays. Moreover, the asymptotic stability test of this system with delays can be abridged to the check of its corresponding 2D stochastic positive linear systems without delays. Many theorems were applied to prove that asymptotic stability for 3D stochastic positive linear systems with delays are equivalent to 2D stochastic positive linear systems without delays. The efficiency of the given methods is illustrated on some numerical examples. HIGHLIGHTS Various theorems were applied to prove the asymptotic stability of 3D stochastic positive linear system with delays. Moreover, this system can be reduced to 2D stochastic positive linear system without delays Asymptotic stability of 3D stochastic positive linear systems with delays depends on the summation of system matrices and independent on numbers and values of delays for that system The principal minors and the coefficients for characteristic polynomials of 3D stochastic linear systems were applied to demonstrate the asymptotic stability when they are all positive
Cams are considered as one of the most important mechanical components that depends the contact action to do its job and suffer a lot of with drawbacks to be predicted and overcame in the design process. this work aims to investigate the induced cam contact and the maximum shear stress energy or (von misses) stresses during the course of action analytically using Hertz contact stress equation and the principal stress formulations to find the maximum stress value and its position beneath the contacting surfaces. The experimental investigation adopted two dimensions photoelastic technique to analyze cam stresses under a plane polarized light. The problem has been numerically simulated using Ansys software version 15 as FE
... Show MoreA two-dimensional computational study had been performed regarding aerodynamic forces and pressures affecting a cambered inverted airfoil, CLARK-Y smoothed with ground effects by solving the Reynolds-averaged Navier-Stokes equations, using the commercial software COMSOL Multiphysics 5.0 solver. Turbulence effects are modeled using the Menter shear-stress transport (SST) two-equation model. The negative lift (down-force), drag forces and pressures surface were predicted through the simulation of wings over inverted wings in different parameters namely; varying incidences i.e. angles of attack of the airfoils, varying the ride hide from the ground covering various force regions, two-dimensional cross-section of the inverted front wings to be
... Show More40 blood sample were taken from children infected with kala-azar at age less than ten years, who were admitted to El-Eskan child hospital, and central health laboratory in Baghdad. At the same time 15 sample collected from healthy child for comparing. During research estimated immunoglobulins level ( IgG, IgM, IgA) and (IFAT) IFAT test recorded a higher indicate antibodies level witch was synergistic with infected severity, the stander level of antibodies arrange between 1/16, 1/32 and 1/64 that means it graduate from the lowest one 1/16 into the highest one 1/64 within groups. During infectious the IgG ,IgM level recorded the higher level (2012.9 mg/dl) and (154.3 mg/dl) compared to the control group (874.3 mg/dl),
... Show MoreThe aim of the present study is to compare the biochemical action of the three vaccines taken in Iraq: Pfizer Biontech, AstraZeneca Oxford and Sinopharm based on biochemical parameters. Seventy COVID-19 Iraqi patients ( males and females ) were participated in the present study and classified into 7 groups : Gc : COVID-19 patients ( without vaccine ) , Gp1: COVID-19 patients took one dose of Pfizer Biontech, Gp2 : COVID-19 patients took two doses of Pfizer Biontech, Ga1 : patients took one dose of AstraZeneca Oxford vaccine , Ga2: patients took two doses of AstraZeneca Oxford vaccine , Gs1 : patients took one dose of Sinopharm vaccine and Gs2:
... Show MoreIn this study, a predicated formula is been proposed to find the shear strength of non-prismatic beams with or without openings. It depends on the contributions of concrete shear strength considering the beam depth variation and existing openings, shear steel reinforcements and defines the critical shear section, the effect of diagonal shear reinforcement, the effect of inclined tensile steel reinforcement, and the compression chord influence. The verification of the proposed formula has been conducted on the experimental test results of 26 non-prismatic beams with or without openings at the same loading conditions. The results reflect that the predicted formula finds the shear capacity of non-prismatic beams with openings, it is co
... Show MoreIn this paper, the process for finding an approximate solution of nonlinear three-dimensional (3D) Volterra type integral operator equation (N3D-VIOE) in R3 is introduced. The modelling of the majorant function (MF) with the modified Newton method (MNM) is employed to convert N3D-VIOE to the linear 3D Volterra type integral operator equation (L3D-VIOE). The method of trapezoidal rule (TR) and collocation points are utilized to determine the approximate solution of L3D-VIOE by dealing with the linear form of the algebraic system. The existence of the approximate solution and its uniqueness are proved, and illustrative examples are provided to show the accuracy and efficiency of the model.
Mathematical Subject Classificat
... Show MoreThis study investigates the analytical approach of web reinforcement techniques, including high-strength concrete and laced reinforcement, to enrich improvement for the structural behavior of these beams. The analysis compares an unmodified cellular beam (LB1) with a web-reinforced beam (LB2), including the improvements in load-carrying capacity. The study considers the effects of reinforcement on critical design limit states, such as flexural strength, Vierendeel bending, web post-buckling, and shear resistance. The outcomes reveal significant enhancements in LB2’s structural behavior, with over a 100% increase in flexural strength and local axial force capacity and a 165% increase