Preferred Language
Articles
/
UhYwmIoBVTCNdQwC0aAE
Modelling and stability analysis of the competitional ecological model with harvesting
...Show More Authors

The interplay of predation, competition between species and harvesting is one of the most critical aspects of the environment. This paper involves exploring the dynamics of four species' interactions. The system includes two competitive prey and two predators; the first prey is preyed on by the first predator, with the former representing an additional food source for the latter. While the second prey is not exposed to predation but rather is exposed to the harvest. The existence of possible equilibria is found. Conditions of local and global stability for the equilibria are derived. To corroborate our findings, we constructed time series to illustrate the existence and the stability of equilibria numerically by varying the different values of the system's parameters. The results show that system movement could happen around the positive equilibria, if the system stability conditions are met.

Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jun 01 2014
Journal Name
Journal Of Engineering
Finite Element Analysis of Reinforced Concrete T-Beams with Multiple Web Openings under Impact Loading
...Show More Authors

Publication Date
Thu Sep 15 2022
Journal Name
Alustath Journal
Semantic Analysis of Proverbs: A Conversation Analysis
...Show More Authors

Proverbs are considered as a major source of ancient events and happenings. Similar to other past events related to life, proverbs have many important and famous values in people's life. This study will shed lights on the use of proverbs as short sentences based on long experiences. The aim of the study is to explicate the roles, and the importance of proverbs in our life and how they are used to convey thoughts to people throughout simple words with denotation. Thus, proverbs explicate the truth and experience of our grandfathers when directed for criticism. Few proverbs were used by writers to criticize, mimic and reprint their personalities. Hence, proverbs will achieve portions of the unique roles of understanding. The model to

... Show More
Crossref (2)
Crossref
Publication Date
Tue Jul 11 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Daniel's Model on the Achievement of Chemistry Among Fifth Grade Student
...Show More Authors

The aim of this research is to find out the influence of Daniel's model on the skills of the twenty-first century among the students of the scientific-fifth grade at the secondary and preparatory government morning schools for the academic year 2022- 2023. Two groups were chosen out of five groups for the fifth-scientific grade, one of which represents the experimental group that is taught by the Daniel model, and the other is the control group that is taught in the traditional method. The equivalence of the two research groups was verified with a set of variables. As for the research tool, a scale was developed by the researchers for the skills of the twenty-first century, in which they adopted the framework of the Partnership Organizat

... Show More
View Publication Preview PDF
Publication Date
Wed Jul 01 2020
Journal Name
Journal Of Physics: Conference Series
A Multilevel Approach for Stability Conditions in Fractional Time Diffusion Problems
...Show More Authors
Abstract<p>The Caputo definition of fractional derivatives introduces solution to the difficulties appears in the numerical treatment of differential equations due its consistency in differentiating constant functions. In the same time the memory and hereditary behaviors of the time fractional order derivatives (TFODE) still common in all definitions of fractional derivatives. The use of properties of companion matrices appears in reformulating multilevel schemes as generalized two level schemes is employed with the Gerschgorin disc theorems to prove stability condition. Caputo fractional derivatives with finite difference representations is considered. Moreover the effect of using the inverse operator which tr</p> ... Show More
View Publication
Scopus Crossref
Publication Date
Thu Dec 28 2017
Journal Name
Al-khwarizmi Engineering Journal
Aircraft Lateral-Directional Stability in Critical Cases via Lyapunov Exponent Criterion
...Show More Authors

Based on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 01 2014
Journal Name
Journal Of Water Resource And Protection
Evaluating Water Stability Indices from Water Treatment Plants in Baghdad City
...Show More Authors

View Publication
Crossref (42)
Crossref
Publication Date
Sat Mar 01 2008
Journal Name
Iraqi Journal Of Physics
Mathematical Model of Amplified Stimulated Raman Scattering and Fiber Raman Amplifier
...Show More Authors

The result of a developed mathematical model for predicting the design
parameters of the fiber Raman amplifier (FRA) are demonstrated. The amplification
parameters are tested at different pump power with different fiber length. Recently,
the FRA employed in optical communication system to increase the repeater distance
as will as the capacity of the communication systems. The output results show, that
high Raman gain can be achieved by high pumping power, long effective area that
need to be small for high Raman gain. High-stimulated Raman gain coefficient is
recommended for high Raman amplifier gain, the low attenuation of the pump and the
transmitted signal in the fiber lead to high Raman gain.

View Publication Preview PDF
Publication Date
Thu Feb 09 2023
Journal Name
Artificial Intelligence Review
Community detection model for dynamic networks based on hidden Markov model and evolutionary algorithm
...Show More Authors

Finding communities of connected individuals in complex networks is challenging, yet crucial for understanding different real-world societies and their interactions. Recently attention has turned to discover the dynamics of such communities. However, detecting accurate community structures that evolve over time adds additional challenges. Almost all the state-of-the-art algorithms are designed based on seemingly the same principle while treating the problem as a coupled optimization model to simultaneously identify community structures and their evolution over time. Unlike all these studies, the current work aims to individually consider this three measures, i.e. intra-community score, inter-community score, and evolution of community over

... Show More
View Publication
Scopus (17)
Crossref (10)
Scopus Clarivate Crossref
Publication Date
Tue Jul 21 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of systemic administration of Simvastatin on dental implant stability: A random clinical study
...Show More Authors

Background: the primary objective for many researches carried out in dental implantology was to reduce the period needed for functional implant loading, simvastatin (cholesterol lowering medication) had many pleiotropic effects, one of which was increasing bone density around titanium implants (1) and subsequently establishing faster osseointegrated dental implants (2,3). This study aims to reduce the period of time needed to establish secondary stability of dental implant measured in ISQ (Implant Stability Quotient) by investigating the effect of orally administered simvastatin on bone. Materials and methods: simvastatin tablets (40mg/day for three months) were administered orally for 11 healthy women aged (40-51) years old who received 1

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
International Journal Of Applied Science And Engineering
The effect of model scale, acceleration history, and soil condition on closed-ended pipe pile response under coupled static-dynamic loads
...Show More Authors

This paper analyzes the effect of scaling-up model and acceleration history on seismic response of closed-ended pipe pile using a finite element modeling approach and the findings of 1 g shaking table tests of a pile embedded in dry and saturated soils. A number of scaling laws were used to create the numerical modeling according to the data obtained from 1 g shake table tests performed in the laboratory. The current study found that the behaviors of the scaled models, in general have similar trends. From numerical modeling on both the dry and saturated sands, the normalized lateral displacement, bending moment, and vertical displacement of piles with scale factors of 2 and 35 are less than those of the pile with a scale factor of 1 and the

... Show More
Scopus (17)
Crossref (11)
Scopus Crossref