In this paper, a discretization of a three-dimensional fractional-order prey-predator model has been investigated with Holling type III functional response. All its fixed points are determined; also, their local stability is investigated. We extend the discretized system to an optimal control problem to get the optimal harvesting amount. For this, the discrete-time Pontryagin’s maximum principle is used. Finally, numerical simulation results are given to confirm the theoretical outputs as well as to solve the optimality problem.
The effect of three high temperatures for five exposure periods on the developments of larvae, pupae and adults of Trogoderma granarium (Everts) and their biological performance were investigated. The results revealed that the percent of mortality was increased as the temperature and the exposure period increased, e. g. exposing last instar larvae to 45°C for 6 hrs caused 100% death of this stage, while exposing adults (1-3) days old to the same temperature and exposure time resulted in that these adults did not able to survive more than 24 hrs.; in addition, the results showed that the ability of reproduction of adults was depended on the temperature, duration of exposure and the sex.
The biological activity of vitex agnus castus L. was tested which including the following extracts: essential oil extract, methanol extract, (70%), ethanol extract( 70%), flavonoid extract and volatile oils extract were tested against many types of bacteria which are Staphylococus aureus , Bacillus pumilus, Escerichia coli,
Pseudomonas, Enterobacter and Streptococcus sp., The results of this study showed difference activity of these extracts .The flavonoid extract considers the best activities which gave inhibition zone (20) mm on E. coli, Pseudomonas ; Staphylococus aureus of (15) mm on Bacillus pumilus and (9) mm on Streptococcus sp. Ethanol extract gave inhibition zone (15) mm on Staphylococus aureus, (11) mm on Streptococcus sp. (
In this paper we estimate the coefficients and scale parameter in linear regression model depending on the residuals are of type 1 of extreme value distribution for the largest values . This can be regard as an improvement for the studies with the smallest values . We study two estimation methods ( OLS & MLE ) where we resort to Newton – Raphson (NR) and Fisher Scoring methods to get MLE estimate because the difficulty of using the usual approach with MLE . The relative efficiency criterion is considered beside to the statistical inference procedures for the extreme value regression model of type 1 for largest values . Confidence interval , hypothesis testing for both scale parameter and regression coefficients
... Show MoreIn the present work, the magnetic dipole and electric quadrupole moments for some sodium isotopes have been calculated using the shell model, considering the effect of the two-body effective interactions and the single-particle potentials. These isotopes are; 21Na (3/2+), 23Na (3/2+), 25Na (5/2+), 26Na (3+), 27Na (5/2+), 28Na (1+) and, 29Na (3/2+). The one-body transition density matrix elements (OBDM) have been calculated using the (USDA, USDB, HBUMSD and W) two-body effective interactions carried out in the sd-shell model space. The sd shell model space consists of the active 2s1/2, 1d5/2,
... Show MoreResearch Objectives: The research aims to highlight the approach of Imam Al-Qaradawi in contemporary jurisprudence in the recent issues of the jurisprudence of minorities, and mentioning the foundations of jurisprudence of minorities, along with some of the practical applications of Imam Al-Qaradawi.
Study Methodology: The researcher applied the inductive, analytical and comparative approach by tracking the scientific material related to the subject of the study from the books of Al-Qaradawi in the first place, then by comparing the legal provisions with what had been stated in the four schools of jurisprudence.
Findings: The interest and need of Muslim minorities in non-
... Show MorePilots are trained using computerized flight simulators. A flight simulator is a training system where pilots can acquire flying skills without need to practice on a real airplane. Simulators are used by professional pilots to practice flying strategies under emergency or hazardous conditions, or to train on new aircraft types. In this study a framework for flight simulation is presented and the layout of an implemented program is described. The calculations were based on simple theoretical approach. The implementation was based on utilizing some of utilities supported by ActiveX, DirectX and OpenGL written in Visual C++. The main design consideration is to build a simple flight simulation program can operate without need to high computer e
... Show MoreThe objective of this research is employ the special cases of function trapezoid in the composition of fuzzy sets to make decision within the framework of the theory of games traditional to determine the best strategy for the mobile phone networks in the province of Baghdad and Basra, has been the adoption of different periods of the functions belonging to see the change happening in the matrix matches and the impact that the strategies and decision-making available to each player and the impact on societ
... Show MoreBackground: Tumor necrosis factor-alpha (TNF-α) and interleukins play important roles in the pathogenesis of rheumatoid arthritis (RA). Genetic research has been employed to find many of the missing connections between genetic risk variations and causal genetic components. Objective: The goal of this study is to look at the genetic variations of TNF-α and interleukins in Iraqi RA patients and see how they relate to disease severity or response to biological therapy. Method: Using specific keywords, the authors conducted a systematic and comprehensive search to identify relevant Iraqi studies examining the genetic variations of TNF-α and interleukins in Iraqi RA patients and how they relate to disease severity or response to biolo
... Show MoreThis study describes the preparation of new series of tetra-dentate N2O2 dinuclear complexes (Cr3+, Co2+, Cu2+) of the Schiff base derived from condensation of 1-Hydroxy-naphthalene-2-carbaldehyde with 2-amino-5-(2-hydroxy-phenyl)-1,3,4-thiadiazole. The structures of the ligands were identified using IR, UV-Vis , mass, elemental analysis and 1H-NMR techniques. All prepared complexes have been characterized by conductance measurement, magnetic susceptibility, electronic spectra, infrared spectrum, theromgravimatric analysis (TGA) and metal analysis by atomic absorption. From stoichiometry of metal to ligand and all measurements show a octahedral geometry proposed for all complexes of the (Cr3+, Co2+, Cu2+). conductivity measurement shows t
... Show MoreThis study describes the preparation of new series of tetra-dentate N2O2 dinuclear complexes (Cr3+, Co2+, Cu2+) of the Schiff base derived from condensation of 1-Hydroxy-naphthalene-2-carbaldehyde with 2-amino-5-(2-hydroxy-phenyl)-1,3,4-thiadiazole. The structures of the ligands were identified using IR, UV-Vis , mass, elemental analysis and 1H-NMR techniques. All prepared complexes have been characterized by conductance measurement, magnetic susceptibility, electronic spectra, infrared spectrum, theromgravimatric analysis (TGA) and metal analysis by atomic absorption. From stoichiometry of metal to ligand and all measurements show a octahedral geometry proposed for all
... Show More