Preferred Language
Articles
/
bsj-1295
Oscillations of First Order Linear Delay Differential Equations with positive and negative coefficients
...Show More Authors

Oscillation criteria are obtained for all solutions of the first-order linear delay differential equations with positive and negative coefficients where we established some sufficient conditions so that every solution of (1.1) oscillate. This paper generalized the results in [11]. Some examples are considered to illustrate our main results.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Jul 21 2022
Journal Name
Energies
Dynamic Characteristics and Demonstration of an Integrated Linear Engine Generator with Alternative Electrical Machines
...Show More Authors

A linear engine generator with a compact double-acting free piston mechanism allows for full integration of the combustion engine and generator, which provides an alternative chemical-to-electrical energy converter with a higher volumetric power density for the electrification of automobiles, trains, and ships. This paper aims to analyse the performance of the integrated engine with alternative permanent magnet linear tubular electrical machine topologies using a coupled dynamic model in Siemens Simcenter software. Two types of alternative generator configurations are compared, namely long translator-short stator and short translator-long stator linear machines. The dynamic models of the linear engine and linear generator, validated

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Mon Nov 01 2021
Journal Name
Chaos, Solitons & Fractals
Dynamic analysis of a harvested fractional-order biological system with its discretization
...Show More Authors

View Publication
Scopus (26)
Crossref (19)
Scopus Clarivate Crossref
Publication Date
Mon May 01 2017
Journal Name
Applied Mathematics And Computation
Reconstruction of time-dependent coefficients from heat moments
...Show More Authors

View Publication
Scopus (32)
Crossref (16)
Scopus Clarivate Crossref
Publication Date
Sun Sep 01 2019
Journal Name
Baghdad Science Journal
Symmetric and Positive Definite Broyden Update for Unconstrained Optimization
...Show More Authors

Broyden update is one of the one-rank updates which solves the unconstrained optimization problem but this update does not guarantee the positive definite and the symmetric property of Hessian matrix.

In this paper the guarantee of positive definite and symmetric property for the Hessian matrix will be established by updating the vector  which represents the difference between the next gradient and the current gradient of the objective function assumed to be twice continuous and differentiable .Numerical results are reported to compare the proposed method with the Broyden method under standard problems.

View Publication Preview PDF
Scopus (10)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sat Mar 21 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Hosting Events and its Positive Impact on the City
...Show More Authors

Abstract : This research is a field study of international cities that hosted various events of which (Sports, Exhibitions, Scientific, Cultural) and other events, these positive impacts on the city driven by such hosts were identified. The research goal was to support hosting events to improve the hostess city and to draw future plans for further developments and to invest event’s hosting to strengthen the city’s value according to a strategic vision that looks for the future the most important conclusions are Entering events hosting is a part of urban development strategies and The most important recommendations are coordination between hosting event activities and its facilities with the infrastructure structure of the host city, its

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Mon Jan 01 2024
Journal Name
Aip Conference Proceedings
Negative skin friction evaluation and mitigation: A review study
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Thu Oct 06 2022
Journal Name
Advances In Systems Science And Applications
Stability and Bifurcation of a Delay Cancer Model in the Polluted Environment
...Show More Authors

It is well known that the spread of cancer or tumor growth increases in polluted environments. In this paper, the dynamic behavior of the cancer model in the polluted environment is studied taking into consideration the delay in clearance of the environment from their contamination. The set of differential equations that simulates this epidemic model is formulated. The existence, uniqueness, and the bound of the solution are discussed. The local and global stability conditions of disease-free and endemic equilibrium points are investigated. The occurrence of the Hopf bifurcation around the endemic equilibrium point is proved. The stability and direction of the periodic dynamics are studied. Finally, the paper is ended with a numerical simul

... Show More
View Publication
Scopus (2)
Scopus
Publication Date
Fri Apr 01 2016
Journal Name
Communications In Nonlinear Science And Numerical Simulation
Simultaneous determination of time and space-dependent coefficients in a parabolic equation
...Show More Authors

View Publication
Scopus (22)
Crossref (11)
Scopus Clarivate Crossref
Publication Date
Mon Mar 01 2021
Journal Name
Iraqi Journal Of Physics
Linear and Non-Linear Optical Properties for Organic Semiconductor (CuPc) Thin Films
...Show More Authors

Thin films of CuPc of various thicknesses (150,300 and 450) nm have been deposited using pulsed laser deposition technique at room temperature. The study showed that the spectra of the optical absorption of the thin films of the CuPc  are two bands of absorption one in the visible region at about 635 nm, referred to as Q-band, and the second in ultra-violet region where B-band is located at 330 nm. CuPc thin films were found to have direct band gap with values around (1.81 and 3.14 (eV respectively. The vibrational studies were carried out using Fourier transform infrared spectroscopy (FT-IR). Finally, From open and closed aperture Z-scan data non-linear absorption coefficient and non-linear refractive index have been calculated res

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Mar 18 2016
Journal Name
International Journal Of Basic And Applied Sciences
Analytic and numerical solution for duffing equations
...Show More Authors

<p>Daftardar Gejji and Hossein Jafari have proposed a new iterative method for solving many of the linear and nonlinear equations namely (DJM). This method proved already the effectiveness in solved many of the ordinary differential equations, partial differential equations and integral equations. The main aim from this paper is to propose the Daftardar-Jafari method (DJM) to solve the Duffing equations and to find the exact solution and numerical solutions. The proposed (DJM) is very effective and reliable, and the solution is obtained in the series form with easily computed components. The software used for the calculations in this study was MATHEMATICA<sup>®</sup> 9.0.</p>

View Publication
Crossref (17)
Crossref