This paper is concerned with a Holling-II stage-structured predator-prey system in which predators are divided into an immature and mature predators. The aim is to explore the impact of the prey's fear caused by the dread of mature predators in a prey-predator model including intraspecific competitions and prey shelters. The theoretical study includes the local and global stability analysis for the three equilibrium points of the system and shows the prey's fear may lead to improving the stability at the positive equilibrium point. A numerical analysis is given to ensure the accuracy of the theoretical outcomes and to testify the conditions of stability of the system near the non-trivial equilibrium points.
The current paper aims to identify potential factors associated with employees’ intentions to leave information and communication technology companies in Iraq. There is evident variability in the literature regarding these factors; hence, a factor analysis approach was employed to identify these factors within the surveyed environment. Due to the difficulty in precisely delineating the size of the research population, a purposive sampling method was employed to reach an appropriate number of respondents within the aforementioned companies. A total of 288 employees responded to the survey conducted via Google Forms. The test results revealed the presence of five primary factors associated with employees’ intentions to leave, name
... Show MoreThe determination of manganese (II) using flow injection analysis with chemiluminescence detection was investigated. Mn2+ in sample solutions injected into a carrier stream of sodium bismuthate (NaBiO3) were oxidised to form MnO4- ions which were capable of producing luminescence after reaction with luminol/KOH in a flow cell. The linear range of the system is from 20 to 80 mg/L with a detection limit 8 mg/L. The proposed system is suitable for determination of Mn2+ in steel alloys after dissolution, filtration and dilution at a rate of approximately 60 samples per hour with a relative standard deviation (RSD)1.2%. Statistical comparison between the proposed system and standard spectrophotometric method revealed that there is no signific
... Show MoreResearchers often equate database accounting models in general and the Resources-Events-Agents (REA) accounting model in particular with events accounting as proposed by Sorter (1969). In fact, REA accounting, database accounting, and events accounting are very different. Because REA accounting has become a popular topic in AIS research, it is important to agree on exactly what is meant by certain ideas, both in concept and in historical origin. This article clarifies the analyzing framework of REA accounting model and highlights the differences between the terms events accounting, database accounting, semantically-modeled accounting, and REA accounting. It als
... Show MoreThe current theoretical research targeted to construct a model of terrorist personality and its differentiation from psychopathic personality . Several assumptions or theories of perspectives of psychopathic personality have been compared with the terrorist personality studies that concerned . The suggested theoretical model is interrupting the terrorist personality . The conclusions , discussions are mentioned. Finally, recommendation is suggested .
Music and singing are always associated with the movement of society and the emergence of cultural and artistic activities other.
The social and political transformations of the 1930s helped to disseminate the study Music and music in the city of Baghdad and across Iraq This is the beginning of a new era of musical art alongside other arts.
While achieving musical arts A new step was advanced by publishing a technical study among the younger generation they were looking for to contribute to the musical field On the other hand, the city of Baghdad during the period of research many musical and musical performances Egyptian teams have provided many artistic activities and events which have had a significant impact on the development
Atheists have spread in the modern era, so that atheism has become a bad phenomenon in the world in general and in Islamic societies in particular, so the research aims to study the individual and social effects left by atheism on the atheists themselves, and the research included multiple axes: atheism linguistically and idiomatically, atheism in the Qur’an Noble and Modern (and Contemporary) Atheism Statistics: and the reasons for atheism: Studying the phenomenon of atheism in Iraq as a model, then studying the effects of atheism: on the individual first, then atheism and its impact on society, then the conclusion, recommendations, sources and references
The tourism industry has become, currently, an art, an industry and a science. It is also one of the components that make up touristic regions. Tourist attractions are no longer the exclusive visits of museums and archeological sites, but also involve other service facilities. It is, therefore, imperative that the authorities should become aware of the degradation of tourist resorts and prevent them from getting worse. Moreover, the authorities should take a set of decisions concerning the protection of the urban aspect with its historical, social, and environmental dimensions, as well as, adapting it to the modern requirements that can bring comfort to the citizens and tourists at physical and psychological levels.
This work aims to analyze a three-dimensional discrete-time biological system, a prey-predator model with a constant harvesting amount. The stage structure lies in the predator species. This analysis is done by finding all possible equilibria and investigating their stability. In order to get an optimal harvesting strategy, we suppose that harvesting is to be a non-constant rate. Finally, numerical simulations are given to confirm the outcome of mathematical analysis.
Wellbore instability is a significant problem faced during drilling operations and causes loss of circulation, caving, stuck pipe, and well kick or blowout. These problems take extra time to treat and increase the Nonproductive Time (NPT). This paper aims to review the factors that influence the stability of wellbores and know the methods that have been reached to reduce them. Based on a current survey, the factors that affect the stability of the wellbore are far-field stress, rock mechanical properties, natural fractures, pore pressure, wellbore trajectory, drilling fluid chemicals, mobile formations, naturally over-pressured shale collapse, mud weight, temperature, and time. Also, the most suitable ways to reduce well
... Show MoreIn this paper, a Cournot oligopoly with isoelastic demand function and constant marginal cost is considered. The local stability conditions of the Cournot equilibrium are determined for four models with different decision mechanisms. In the first model, firms adjust their outputs using the best reply response with naive expectations. The second model is a generalization of the first one, where firms have adaptive expectations. Meanwhile, the third and fourth models adopt the bounded rationality and local monopolistic approximation, respectively. The results show that, in the case of identical firms, the Cournot equilibrium is always stable when the firms adopt the local monopolistic approximation mechanism.