Preferred Language
Articles
/
GBbUtYkBVTCNdQwCgYzr
Stability and bifurcation of a prey-predator system incorporating fear and refuge
...Show More Authors

It is proposed and studied a prey-predator system with a Holling type II functional response that merges predation fear with a predator-dependent prey's refuge. Understanding the impact of fear and refuge on the system's dynamic behavior is one of the objectives. All conceivable steady-states are investigated for their stability. The persistence condition of the system has been established. Local bifurcation analysis is performed in the Sotomayor sense. Extensive numerical simulation with varied parameters was used to explore the system's global dynamics. A limit cycle and a point attractor are the two types of attractors in the system. It's also interesting to note that the system exhibits bi-stability between these 2 types of attractors. Fear also has a destabilizing effect on the dynamics of the system.

Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Dec 09 2022
Journal Name
Scientific Research Journal Of Economics And Business Management
The Effect of Public Spending on the Monetary Sterilization Factor in the Iraqi Economy for the Period 2005-2021
...Show More Authors

Monetary sterilization policies are one of the modern trends of monetary policy in rentier countries, specifically to confront the positive shocks in foreign assets flowing into the national economy and the impact of these shocks on monetary and real variables. And that the Central Bank contains these emergency increases in foreign exchange with the aim of avoiding the impact of this increase on the official local currency through its three main monetary tools, which are the rediscount rate, the legal reserve, and open market operations. As well as the relationship between the central bank and the objective of external balance, which is reflected in the balance of payments balance, the central bank resorts to managing the exchange rate

... Show More
View Publication Preview PDF
Publication Date
Tue May 28 2019
Journal Name
Al-khwarizmi Engineering Journal
Heuristic D* Algorithm Based on Particle Swarm Optimization for Path Planning of Two-Link Robot Arm in Dynamic Environment
...Show More Authors

 Finding a path solution in a dynamic environment represents a challenge for the robotics researchers, furthermore, it is the main issue for autonomous robots and manipulators since nowadays the world is looking forward to this challenge. The collision free path for robot in an environment with moving obstacles such as different objects, humans, animals or other robots is considered as an actual problem that needs to be solved.  In addition, the local minima and sharp edges are the most common problems in all path planning algorithms. The main objective of this work is to overcome these problems by demonstrating the robot path planning and obstacle avoidance using D star (D*) algorithm based on Particle Swarm Optimization (PSO)

... Show More
View Publication Preview PDF
Crossref (7)
Crossref
Publication Date
Sun Feb 28 2021
Journal Name
Journal Of Economics And Administrative Sciences
Effects of Macroeconomic Variables on Gross Domestic Product in Saudi Arabia using ARDL model for the period 1993-2019
...Show More Authors

 

This paper analyses the relationship between selected macroeconomic variables and gross domestic product (GDP) in Saudi Arabia for the period 1993-2019. Specifically, it measures the effects of interest rate, oil price, inflation rate, budget deficit and money supply on the GDP of Saudi Arabia. The method employs in this paper is based on a descriptive analysis approach and ARDL model through the Bounds testing approach to cointegration. The results of the research reveal that the budget deficit, oil price and money supply have positive significant effects on GDP, while other variables have no effects on GDP and turned out to be insignificant. The findings suggest that both fiscal and monetary policies should be fo

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jan 01 2014
Journal Name
Journal Of The College Of Languages (jcl)
The Influence of Manipulating the Virtual Library in Comparison with the Individual Learning via Computer Use in English Language
...Show More Authors

The study aims at investigating the effectiveness of the Virtual Library Technology, in developing the achievement of the English Language Skills in the Center of Development and Continuous Education, in comparison with the individual learning via personal computer to investigate the students' attitude towards the use of both approaches. The population of the study includes the participants in the English Language course arranged in the Center. The sample includes 60 students who were randomly chosen from the whole population (participants in English Courses for the year 2009-2010). The sample is randomly chosen and divided into two experimental groups. The first group has learned through classroom technology; while the other group has l

... Show More
View Publication Preview PDF
Publication Date
Tue Mar 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
The Bayesian Estimation for The Shape Parameter of The Power Function Distribution (PFD-I) to Use Hyper Prior Functions
...Show More Authors

The objective of this study is to examine the properties of Bayes estimators of the shape parameter of the Power Function Distribution (PFD-I), by using two different prior distributions for the parameter θ and different loss functions that were compared with the maximum likelihood estimators. In many practical applications, we may have two different prior information about the prior distribution for the shape parameter of the Power Function Distribution, which influences the parameter estimation. So, we used two different kinds of conjugate priors of shape parameter θ of the <

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Statistical quality control charts for measuring educational service quality at Albaha University, Saudi Arabia, from the viewpoint of students
...Show More Authors

تم استخدام خرائط ضبط الجودة الإحصائية لتقييم جودة الخدمة التعليمية في جامعة الباحة،  ويهدف هذا البحث إلى استخدام خرائط ضبط الجودة الإحصائية لقياس مستوى الجودة وفجوة الجودة بين توقعات الطلبة وإدراكاتهم لمستوى الخدمة الذي تقدمه جامعة الباحة. حيث تم اختيار عينة من 200 طالب وطالبة عشوائيا باستخدام العشوائية العنقودية من 4 كليات خلال الفترة 01 – 30/2015م، وجمعت البيانات من خلال استبيان جودة الخدمة الذي يقيس ت

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Dec 24 2018
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FAUNISTIC REVIEW OF THE GENUS CHAITOPHORUS KOCH, 1854 (APHIDIDAE, CHAITOPHORINAE, CHAITOPHORINI) WITH NEW RECORD SPECIES FOR IRAQ APHID FAUNA
...Show More Authors

    A faunistic review of the genus Chaitophorus Koch, 1854, including four species in Iraq is given; the distribution data of each species and their hosts have been recorded. In this investigation the poplar leaf aphid Ch. populialbae (Boyer de Fonscolombe, 1841) is recorded here for the first time in Iraq on popular trees Populus euphratica Oliv. during the period from November 2016 to April 2017 in Baghdad province.

 

    A brief description for apterous viviparous female of this species is given; and a  key to the species of the genus Chaitophorus is constricted.

View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Wed Jun 24 2020
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
NEW RECORD OF BRACHYDISTOMUM MICROSCELIS (YAMAGUTI, 1933) (TREMATODA, DICROCOELIIDAE) FROM HOUSE SPARROWPASSER DOMESTICUS BIBLICUS HARTERT, 1904 IN BAGHDAD, IRAQ
...Show More Authors

A total of 30 specimens of house sparrow Passer domesticus biblicus Hartert, 1904 (15 females and 15 males) were collected from gardens of some houses in Baghdad city; all birds were dissected to identify the parasites in vesicle, gizzard, intestine, gall bladder and caecum. One species of trematodes Brachydistomum microscelis (Yamaguti, 1933) was found in the gall bladder and two species of cestodes Anonchotaenia globata (von Linstow, 1879) and Raillietina tetragona (Molin, 1858) were found in the small intestine of house sparrow. Morphologic and morphometric measurements were considered.

   The genus Brachydistomum Travassos, 1944 is being recorded for the first time in Iraq in the gall bladder of house sparr

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Engineering
An An Accurate Estimation of Shear Wave Velocity Using Well Logging Data for Khasib Carbonate Reservoir - Amara Oil Field
...Show More Authors

   

Shear and compressional wave velocities, coupled with other petrophysical data, are vital in determining the dynamic modules magnitude in geomechanical studies and hydrocarbon reservoir characterization. But, due to field practices and high running cost, shear wave velocity may not available in all wells. In this paper, a statistical multivariate regression method is presented to predict the shear wave velocity for Khasib formation - Amara oil fields located in South- East of Iraq using well log compressional wave velocity, neutron porosity and density. The accuracy of the proposed correlation have been compared to other correlations. The results show that, the presented model provides accurate

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Mar 31 2018
Journal Name
Journal Of Engineering
Effect of Using Extra Fins on the Pin Fin Classic Geometry for Enhancement Heat Sink Performance using EGM Method
...Show More Authors

In the present study, the effect of new cross-section fin geometries on overall thermal/fluid performance had been investigated. The cross-section included the base original geometry of (triangular, square, circular, and elliptical pin fins) by adding exterior extra fins along the sides of the origin fins. The present extra fins include rectangular extra fin of 2 mm (height) and 4 mm (width) and triangular extra fin of 2 mm (base) 4 mm (height). The use of entropy generation minimization method (EGM) allows the combined effect of thermal resistance and pressure drop to be assessed through the simultaneous interaction with the heat sink. A general dimensionless expression for the entropy generation rate is obtained by con

... Show More
View Publication Preview PDF
Crossref (4)
Crossref