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On the Stability of Four Dimensional Lotka-Volterra Prey-Predator System
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The aim of this work is to study a modified version of the four-dimensional Lotka-Volterra model. In this model, all of the four species grow logistically. This model has at most sixteen possible equilibrium points. Five of them always exist without any restriction on the parameters of the model, while the existence of the other points is subject to the fulfillment of some necessary and sufficient conditions. Eight of the points of equilibrium are unstable and the rest are locally asymptotically stable under certain conditions, In addition, a basin of attraction found for each point that can be asymptotically locally stable. Conditions are provided to ensure that all solutions are bounded. Finally, numerical simulations are given to verify and support the obtained theoretical results.

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Publication Date
Fri Sep 15 2023
Journal Name
Al-academy
Four Women: The E. Cassirer’s Theory and Its Analytical Potential for Understanding Iraqi Symbolic Painting by J. Saleem
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Based on the theoretical ideas of E. Cassirer, a methodology is developed and an analysis of the painting work by J. Saleem, a representative of modern Iraqi painting, is carried out. While comparing the artistic programme of J. Saleem and the views of E. Cassirer, the methodological potential of the theory of the symbol for the art criticism analysis of the regional painting is clarified. Comparative analysis with the inclusion of the works of B. Buffet, B. Turetsky, J. Miro helps to see the multiple meanings of the same cultural symbol in thematically similar works of different years, created in different socio-cultural circumstances. The article shows that for regions with a shorter history (France, Russia, Spain, etc.), which have lo

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Publication Date
Tue Jun 12 2018
Journal Name
المجلة العراقية لبحوث السوق وحماية المستهلك
BIOLOGICAL ASPECTS AND PREDATORY EFFICIENY OF PREDATOR Chilocorus bipustulatus (L.) COLEOPTERA :COCCINELLIDAE ON DATE PALM SCALE Parlatoria blanchardi (T.) DIASPIDIDAE: HOMOPTERA UNDER LABORATORY CONDITIONS.
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Laboratory studies were conducted at the biological control unit, college of Agriculture, University of Baghdad to evaluate some biological aspects of the predator Chilocorus bipustulatus (Coleoptera: Coccinellidae), which is considered one of the most important predators on many insect pests, especially the scale insect, Parlatoria blanchardi, (Homoptera: Diaspididae) on date palms. The results showed that biological parameters of the predator were varied according to different degree of temperature. Egg incubation period was significantly different and reached to 7.5 and 5.44 day at 25 and 30°C respectively, Fertility was the same 100% at both temperature degrees. Larval growth periods were 17.41 and 16.12 day as well as the mortality du

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Publication Date
Mon May 09 2022
Journal Name
International Academic Journal Of Economics
Analysis of the Relationship between Fiscal Policy Shocks and Monetary Stability in Iraq's Economy for the Period 1990-2018
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The research aims to measure the impact of positive and negative fiscal policy shocks on monetary stability in Iraq, which represents monetary stability as an indicator of real and price stability. Fiscal policy shocks are quantitative changes in public spending and public revenue affecting the output and price cycle, and fiscal policy despite the accompanying time gaps, but it remains a policy Influential and has a significant degree of impact on economic growth and development in developing countries. The fiscal policy represents a numerical translation of the economic and social objectives planned in the state's general budget tool consistent with the GDP cycle. The economic and social goals stem from the core of the functions and the ma

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
The dynamics of two harmful phytoplankton and herbivorous zooplankton system
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In this paper, a mathematical model consisting of the two harmful
phytoplankton interacting with a herbivorous zooplankton is proposed and studied.
The existence of all possible equilibrium points is carried out. The dynamical
behaviors of the model system around biologically feasible equilibrium points are
studied. Suitable Lyapunov functions are used to construct the basins of attractions
of those points. Conditions for which the proposed model persists are established.
The occurrence of local bifurcation and a Hopf bifurcation are investigated. Finally,
to confirm our obtained analytical results and specify the vital parameters, numerical
simulations are used for a hypothetical set of parameter values.

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Publication Date
Sat Jun 15 2019
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Some Factors Affecting The Stability Of Rutin In Buffered Aqueous Extract Of The Plant Alhagi Graecorum
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The flavonoid rutin is the main content of the a queous extract of
the Iraqi plant Alhagi graecorum (family Leguminosae) which was
given to patients with different dental diseases and gave successful
results In this investigation , the amount of rutin is determined and was
found to be 4mg/100gm of the dried plant and it is equivalent to
4mg/500ml (0.8mg/100ml) of the mouthwash formula which was
prepared in this study This study reported for the first time the expiration date of rutin
in the prepared formula and was found to be 2.1 years. It also reported
for the first time that the ionic strength, buffer type and buffer concentration had no effect on the hydrolysis of rutin. Photochemical decomposition of

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Publication Date
Mon Dec 11 2017
Journal Name
Al-khwarizmi Engineering Journal
Study the Characterization of Adding Polymer-Surfactant Agent on the Drag Reduction Phenomena in Pipeline Flow System
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  Abstract    

In this study, the effect of carboxylic methyl cellulose (CMC), and sodium dodcyl benzene sulfonate (SDBS) as an aqueous solution on the drag reduction was investigated. Different concentrations of (CMC) and (SDBS) such as (50, 100, 150, 200, 250, 300, 350, 400, 450, and 500 ppm) were used to analyze the aqueous solution properties, including surface tension, conductivity, and shear viscosity. The optimum four concentrations (i.e., 50, 100, 200, and 300 ppm) of fluid properties were utilized to find their effect on the drag reduction. Two different PVC pipe diameters (i.e., 1" and 3/4") were used in this work. The  results showed that blending CMC with SDBS gives

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Publication Date
Fri Jan 10 2025
Journal Name
Sciences Journal Of Physical Education
The effect of skill exercises according to the Keller model on attentional control and learning the shooting skills from stability and movement of basketball for female students
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Publication Date
Wed Jun 01 2022
Journal Name
Journal Of The College Of Languages (jcl)
The passive As a grammatical phenomenon in four selected textbooks: Das Passiv Als grammatisches Phӓnomen in vier ausgewӓhlten Lehrwerken
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The research work is "The passive voice as a grammatical phenomenon in four selected textbooks". The research deals with the grammatical phenomenon passive in German. The research consists of two parts, the theoretical and the empirical part. The present research work is divided into 3 sections:

The first section includes the definition of passive, passive types, process passive, state passive, passive with modal verbs, and other types of passive. The second section provides illustrations of the four selected textbooks. The third chapter presents the passive voice in textbooks, namely German language teaching for foreigners by Dora Schulz and Heinz Griesbach, Delfin von Aufderstrasse H. and others, Em von Balme, M. and others and

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Publication Date
Mon May 11 2020
Journal Name
Baghdad Science Journal
Proposing Robust LAD-Atan Penalty of Regression Model Estimation for High Dimensional Data
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         The issue of penalized regression model has received considerable critical attention to variable selection. It plays an essential role in dealing with high dimensional data. Arctangent denoted by the Atan penalty has been used in both estimation and variable selection as an efficient method recently. However, the Atan penalty is very sensitive to outliers in response to variables or heavy-tailed error distribution. While the least absolute deviation is a good method to get robustness in regression estimation. The specific objective of this research is to propose a robust Atan estimator from combining these two ideas at once. Simulation experiments and real data applications show that the proposed LAD-Atan estimator

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Publication Date
Mon May 11 2020
Journal Name
Baghdad Science Journal
Proposing Robust LAD-Atan Penalty of Regression Model Estimation for High Dimensional Data
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         The issue of penalized regression model has received considerable critical attention to variable selection. It plays an essential role in dealing with high dimensional data. Arctangent denoted by the Atan penalty has been used in both estimation and variable selection as an efficient method recently. However, the Atan penalty is very sensitive to outliers in response to variables or heavy-tailed error distribution. While the least absolute deviation is a good method to get robustness in regression estimation. The specific objective of this research is to propose a robust Atan estimator from combining these two ideas at once. Simulation experiments and real data applications show that the p

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