Preferred Language
Articles
/
joe-221
Numerical Investigation Using Harmonic and Transient Analysis To Rotor Dynamics
...Show More Authors

The rotor dynamics generally deals with vibration of rotating structures. For designing rotors of a high speeds, basically its important to take into account the rotor dynamics characteristics. The modeling features for rotor and bearings support flexibility are described in this paper, by taking these characteristics of rotor dynamics features into standard Finite Element Approach (FEA) model. Transient and harmonic analysis procedures have been found by ANSYS, the idea has been presented to deal with critical speed calculation. This papers shows how elements BEAM188 and COMBI214 are used to represent the shaft and bearings, the dynamic stiffness and damping coefficients of journal bearings as a matrices have been found with the variation of rotation speed of the rotor which are vary with eccentricity of journal with bearings and this eccentricity is a function of Sommerfeld number, the first critical speed analysis has been done from Campbell diagram, the critical speed it is the speed at which resonance case happen, the unbalance response analysis has been done with changing the unbalance mass then finding the maximum response of the rotor for each unbalance mass case, by Campbell diagram plot recognizing the stability of the system and find the line of un stability, above and down this line the system is stable and if speed lies on this line the system is unstable, the main reason of analysis of rotor dynamics is to help Engineers to characterize the lateral dynamics characteristics of a given design with Campbell diagram plot, can find the critical speed, the unbalance response and the system stability .

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Feb 01 2021
Journal Name
Meta Gene
Association analysis of FTO gene polymorphisms rs9939609 and obesity risk among the adults: A systematic review and meta-analysis
...Show More Authors

View Publication
Scopus (16)
Scopus
Publication Date
Sat Jun 01 2024
Journal Name
Results In Engineering
Thermodynamic modeling and performance analysis of photovoltaic-thermal collectors integrated with phase change materials: Comprehensive energy and exergy analysis
...Show More Authors

View Publication
Scopus (23)
Crossref (10)
Scopus Crossref
Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Using game theory models to determine the profit maximization policies for PepsiCo and Coca Cola in Baghdad
...Show More Authors

(Use of models of game theory in determining the policies to maximize profits for the Pepsi Cola and Coca-Cola in the province of Baghdad)

Due to the importance of the theory of games especially theories of oligopoly in the study of the reality of competition among companies or governments and others the researcher linked theories of oligopoly to Econometrics to include all the policies used by companies after these theories were based on price and quantity only the researcher applied these theories to data taken from Pepsi Cola and Coca-Cola In Baghdad Steps of the solution where stated for the models proposed and solutions where found to be balance points is for the two companies according to the princi

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Using financial ratio to compare performance of the commercial and the Islamic banks Listed on Palestine Exchange
...Show More Authors

        The research aimed to compare the performance of the commercial and the  Islamic banks listed in the Palestinian's Stock Exchange .To achieve the objectives of the study we selected all  the commercial and the Islamic banks listed in the Palestinian Stock Exchange  to obtain the necessary data for the analysis process during the period of (2009-2013) .the comparison based on the performance indicators ( liquidity rate, profitability rate ,the activity rate and the market rate).

        a statistical method was used to analyze the date to find the performance differences between the commercial banks,

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Jan 01 2022
Journal Name
Geotechnical Engineering And Sustainable Construction
Dynamic Response of Slender Reinforced Concrete Columns Strengthened by Using CFRP and Circularization Subjected to Seismic Excitation
...Show More Authors

View Publication
Crossref
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Dynamic algorithm (DRBLTS) and potentially weighted (WBP) to estimate hippocampal regression parameters using a techniqueBootstrap (comparative study)
...Show More Authors

Bootstrap is one of an important re-sampling technique which has given the attention of  researches recently. The presence of outliers in the original data set may cause serious problem to the classical bootstrap when the percentage of outliers are higher than the original one. Many methods are proposed to overcome this problem such  Dynamic Robust Bootstrap for LTS (DRBLTS) and Weighted Bootstrap with Probability (WBP). This paper try to show the accuracy of parameters estimation by comparison the results of both methods. The bias , MSE and RMSE are considered. The criterion of the accuracy is based on the RMSE value since the method that provide us RMSE value smaller than other is con

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2017
Journal Name
Pakistan Journal Of Biotechnology
Fragmentation of gallbladder stones using transformer streptococcus salivarius and measuring of RNA expression to cholesterol lowering genes
...Show More Authors

Recently, gallbladder stones have been contained bile salt saturated a proximal 70 % cholesterol. This led us to investigate how can use transformer Streptococcus salivarius with plasmid pMG36bsh to fragment cholesterol of gallstones in vitro. Total mRNA of S. salivarius was produced using easy-spinTM, total RNA extraction kit and PCR cDNA-RT to observe the change after percent pMG36bsh vector and prepare S. salivarius have two copies from bsh genes (cgh, bsh) to fragment gallstone in bacterial culture. Our data shows increase bacterial bsh expression help to reduce gallstones concentration in culture when bile salt presented as stimulating agent for the association bsh genes were 77% compare with wild type has the reducing concentration ra

... Show More
View Publication Preview PDF
Scopus (1)
Scopus
Publication Date
Sat Dec 31 2022
Journal Name
Mathematical Modelling Of Engineering Problems
Investigation of Energy Efficient Clustering Algorithms in WSNs: A Review
...Show More Authors

In recent years, Wireless Sensor Networks (WSNs) are attracting more attention in many fields as they are extensively used in a wide range of applications, such as environment monitoring, the Internet of Things, industrial operation control, electric distribution, and the oil industry. One of the major concerns in these networks is the limited energy sources. Clustering and routing algorithms represent one of the critical issues that directly contribute to power consumption in WSNs. Therefore, optimization techniques and routing protocols for such networks have to be studied and developed. This paper focuses on the most recent studies and algorithms that handle energy-efficiency clustering and routing in WSNs. In addition, the prime

... Show More
View Publication
Scopus (9)
Crossref (2)
Scopus Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Aip Conference Proceedings
Investigation hydraulic performance of splash fills packing in cooling tower
...Show More Authors

Heat is one of the most energy forms emitted to atmosphere by industrial processes. Water is considered to be the best material to reduce heat energy since its available in nature in abundance and has the ability to absorb heat efficiently. Cooling towers are ideal alternatives to re-cool hot water instead of throwing it especially in places that lack natural water resources or when there are environmental precautions because water with high temperature would be harmful to the ecosystem when it recycled to natural resources such as rivers and lakes. Also, cooling towers considered economically feasible when using west water. This paper interests with hydraulic characteristics of a counter flow wet cooling tower which was investigated experi

... Show More
View Publication
Scopus (6)
Crossref (3)
Scopus Crossref
Publication Date
Tue Mar 28 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Phytochemical Investigation of Alkaloids in the Iraqi Echinops heterophyllus (Compositae)
...Show More Authors

Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms . They are a large family of compounds synthesized by plants in addition to the bacteria, fungi, and animals,  they often have pharmacological effects. The aim of this study is to isolate and identified alkaloids in a newly studied, wild Iraqi plant named

... Show More
View Publication Preview PDF
Crossref (5)
Crossref