Preferred Language
Articles
/
nBiFx5cBVTCNdQwC8Zwm
The Role of Fear and Predator Dependent Refuge on a Stage Structure Prey-Predator System
...Show More Authors

The present paper investigates the role of fear and predator dependent refuge in the prey-predator system. The system describes the interaction between prey and a stage structure of predator that incorporates Holling II functional response. The predator splits into two compartments immature (juvenile) and mature (adult). The mature predators can hunt and reproduce but this capability is not found in the immature predators, the immature depend on their parents. The growth rate of prey decreases due to the existence of mature predators. The existence, uniqueness, and boundedness of the solution of the system are investigated. Three equilibrium points of the system are determined. The local stability of the system is studied. The global stability of the axial equilibrium point is discussed using the appropriate Lyapunov function, while the basin of attraction of the positive equilibrium point is investigated. The persistence constraints of the system are established. The local and Hopf bifurcation analyses of the system are examined. Lastly, numerical simulations are given to ensure the theoretical results with the help of Matlab program (version R2018b). It is found that the effect of fear plays a substantial role in the dynamic of the system. On the other hand, the refuge’s coefficient continuously affects the system. Furthermore, the variation of the refuge’s coefficient by utilizing different initial points leads to a change in the behavior of the system from stable to unstable and conversely.

Scopus Clarivate Crossref
View Publication
Publication Date
Thu Dec 30 2004
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Oil Removal from Wastewater of Al-Bezerqan Crude Oil Fields by Air Flotation
...Show More Authors

View Publication Preview PDF
Publication Date
Thu Jan 30 2020
Journal Name
Journal Of Engineering
Advanced Oxidation of Antibiotics Polluted Water Using Titanium Dioxide in Solar Photocatalysis Reactor
...Show More Authors

The aim of this study was to investigate antibiotic amoxicillin removal from syn­thetic pharmaceutical wastewater. Titanium dioxide (TiO2) was used in photocatalysis treatment method under natural solar irradiation in a tubular reactor. The photocatalytic removal efficiency was evaluated by the reduction in amoxicillin concentration. The effects of antibiotics concentration, TiO2 dose, irradiation time and the effect of pH were studied. The optimum conditions were found to be irradiation time 5 hr, catalyst dosage 0.6 g/L, flow rate 1 L/min and pH 5. The photocatalytic treatment was able to destruct the amoxicillin in 5 hr and induced an amoxicillin reduction of about 10% with 141.8 kJ/L accumulate

... Show More
View Publication Preview PDF
Crossref (14)
Crossref
Publication Date
Fri Mar 01 2019
Journal Name
Optical Fiber Technology
Highly sensitive measurement of surrounding refractive index using tapered trench–assisted multicore fiber
...Show More Authors

View Publication
Scopus (19)
Crossref (16)
Scopus Clarivate Crossref
Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Engineering
Behavior of Reinforced Concrete Deep Beams Strengthened with Carbon Fiber Reinforced Polymer Strips
...Show More Authors

This research is concerned to investigate the behavior of reinforced concrete (RC) deep beams strengthened with carbon fiber reinforced polymer (CFRP) strips. The experimental part of this research is carried out by testing seven RC deep beams having the same dimensions and steel reinforcement which have been divided into two groups according to the strengthening schemes. Group one was consisted of three deep beams strengthened with vertical U-wrapped CFRP strips. While, Group two was consisted of three deep beams strengthened with inclined CFRP strips oriented by 45o with the longitudinal axis of the beam. The remaining beam is kept unstrengthening as a reference beam. For each group, the variable considered

... Show More
View Publication Preview PDF
Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
Enhancement of NO2 gas sensing behavior for ZnS/PPy nanostructure by loading graphene
...Show More Authors

The pure ZnS and ZnS-Gr nanocomposite have been prepared
successfully by a novel method using chemical co-precipitation. Also
conductive polymer PPy nanotubes and ZnS-PPy nanocomposite
have been synthesized successfully by chemical route. The effect of
graphene on the characterization of ZnS has been investigated. X-ray
diffraction (XRD) study confirmed the formation of cubic and
hexagonal structure of ZnS-Gr. Dc-conductivity proves that ZnS and
ZnS-Gr have semiconductor behavior. The SEM proved that
formation of PPy nanotubes and the Gr nanosheet. The sensing
properties of ZnS-PPy/ZnS-Gr for NO2 gas was investigated as a
function of operating temperature and time under optimal condition.
The sensitivity,

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Aug 01 2015
Journal Name
Journal Of Engineering
Analytical Approach for Load Capacity of Large Diameter Bored Piles Using Field Data
...Show More Authors

An analytical approach based on field data was used to determine the strength capacity of large diameter bored type piles. Also the deformations and settlements were evaluated for both vertical and lateral loadings. The analytical predictions are compared to field data obtained from a proto-type test pile used at Tharthar –Tigris canal Bridge. They were found to be with acceptable agreement of 12% deviation.

               Following ASTM standards D1143M-07e1,2010, a test schedule of five loading cycles were proposed for vertical loads and series of cyclic loads to simulate horizontal loading .The load test results and analytical data of 1.95

... Show More
View Publication Preview PDF
Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Application of SWAT Model for Sediment Loads from Valleys Transmitted to Haditha Reservoir
...Show More Authors

This study included the extraction properties of spatial and morphological basins studied using the Soil and Water Assessment Tool (SWAT) model linked to (GIS) to find the amount of sediment and rates of flow that flows into the Haditha reservoir . The aim of this study is determine the amount of sediment coming from the valleys and flowing into the Haditha Dam reservoir for 25 years ago for the period (1985-2010) and its impact on design lifetime of the Haditha Dam reservoir and to determine the best ways to reduce the sediment transport. The result indicated that total amount of sediment coming from all valleys about (2.56 * 106 ton). The maximum annual total sediment load was about (488.22 * 103 ton) in year 1988

... Show More
View Publication Preview PDF
Publication Date
Fri Nov 29 2019
Journal Name
Iraqi Journal Of Physics
Gas Sensing of (SnO2)1-x(ZnO)x Composite Associating with Electrical Properties
...Show More Authors

Abstract

Semiconductor-based gas sensors were prepared, that use n-type tin oxide (SnO2) and  tin oxide: zinc oxide composite (SnO2)1-x(ZnO)x at different x ratios using pulse laser deposition at room temperature. The prepared thin films were examined to reach the optimum conditions for gas sensing applications, namely X-ray diffraction, Hall effect measurements, and direct current conductivity. It was found that the optimum crystallinity and maximum electron density, corresponding to the minimum charge carrier mobility, appeared at 10% ZnO ratio. This ratio appeared has the optimum NO2 gas sensitivity for 5% gas concentration at 300 °C working temperat

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Tue Mar 31 2015
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Performance of Corrosion Inhibitors Blend for Simulated Industrial Cooling Waters under Dynamic Conditions
...Show More Authors

   The inhibitive action of a blend of sodium nitrite/sodium hexametaphosphate (SN+SHMP) on corrosion of carbon steel in simulated cooling water systems (CWS) has been investigated by weight loss and electrochemical polarization technique. The effect of temperature, velocity, and salts concentrations on corrosion of carbon steel were studied in the absence and presence of mixed inhibiting blend. Also the effect of inhibitors blend concentrations (SN+SHMP), temperatures, and rotational velocity, i.e., Reynolds number (Re) on corrosion rate of carbon steel were investigated using Second-order Rotatable Design (Box-Wilson Design) in performing weight loss and corrosion potential approach. Electrochemical polarization measurements

... Show More
View Publication Preview PDF
Publication Date
Sat Aug 01 2020
Journal Name
Journal Of Engineering
Computation of Critical Submergence Depth to Avoid Surface Vortices at Vertical Pumps Intakes
...Show More Authors

The pumping station became widely used in many fields. Free surface vortices at intakes of pumps are not favorable. It may cause noise, excessive vibration, damage to the pumping structure, reduction in efficiency and flow for hydro-turbines, etc. One of the important problems encountered during the pump intake design is the depth of submergence and other design parameters to avoid strong free-surface vortices formation. This study aims to compute the critical submergence depth with some geometrical and hydraulic limitations by using Computational Fluid Dynamic (CFD) package. The mathematical model was validated with a laboratory model that had been conducted. The model of three intake pipes was investigated under five d

... Show More
View Publication Preview PDF
Crossref (3)
Crossref