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joe-221
Numerical Investigation Using Harmonic and Transient Analysis To Rotor Dynamics
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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 .

 

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Publication Date
Wed Mar 01 2023
Journal Name
Accounting And Financial Sciences Journal
The Extent to which the Quality of Accounting Information Systems Contributes to Reducing Material
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This research dealt with shedding light on the nature of material misrepresentations, in addition to knowing the extent to which the quality of accounting information systems contributes to reducing material misrepresentations On the theoretical side, a number of sources were relied upon in dealing with the research problem and presentation of the topic, while in the practical side, it was relied on the questionnaire form, where the research sample was (accountants and auditors), where 50 forms were distributed and 50 were received, and the data was analyzed and hypotheses tested through the program Statistical spss to show the relationship between the variables. The research reached a number of conclusions, the most important of which is t

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Publication Date
Wed Sep 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Risk Assessment Due to Population Exposure to Lead Particles Emitted from Domestic Electrical Generators
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Portable and stationary electrical generators became quite popular in Iraq soon after the shortage in national electrical
energy after 2003. Multi step risk assessment process is used in this study in the assessment of risks caused by
contamination of indoor air by lead particles emitted from domestic electrical generators. Two portable electrical
generators are tested under controlled indoor conditions (Radial LG (0.9 keV) fueled with benzene and oil and TigMax
(3 keV), fueled with benzene only). Lead particles in air were sampled by using portable dust sampler (Sniffer, L-30).
The atmospheric particulate sampling process is carried out in a flat located in the first floor of a three stories building
located in Baghdad

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Publication Date
Mon Jan 01 2024
Journal Name
Pharmaceutical Sciences Asia
Effect of sub-minimum inhibitory concentrations of ceftriaxone on the Pseudomonas aeruginosa adhesion to human oral mucosal epithelial cells and biofilm formation to polystyrene in vitro
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Publication Date
Tue Jan 01 2019
Journal Name
Journal Of Human Sport And Exercise - 2019 - Spring Conferences Of Sports Science
Effect of taking some of dietary supplements according to special forces exercises to develop some physical abilities, speed and accuracy smash shot for badminton young players
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Set dietary program for some of dietary supplements and training for badminton young players, and identifying effect of taking some of the dietary supplementary for badminton young players. The research population :( badminton young players group (Arminian club). For age group (16-18) years the sample is divided in to two experimental groups within each group (6) players, and two for the exploratory experiment which was within the research sample, they were divided in to two groups, the first group take some of the dietary supplements (multivitamin creating) .the set exercises by the researchers in the main part of the training unit and the second group (amino acids, vitamins) and the set exercises by the researcher. The scientific approach

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Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
The analysis of time series considers one of the mathematical and statistical methods in explanation of the nature phenomena and its manner in a specific time period.
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The analysis of time series considers one of the mathematical and statistical methods in explanation of the nature phenomena and its manner in a specific time period.

Because the studying of time series can get by building, analysis the models and then forecasting gives the priority for the practicing in different fields, therefore the identification and selection of the model is of great importance in spite of its difficulties.

The selection of a standard methods has the ability for estimation the errors in the estimated the parameters for the model, and there will be a balance between the suitability and the simplicity of the model.

In the analysis of d

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Publication Date
Mon Feb 23 2026
Journal Name
Modern Sport
Comparison of the speed of hospitalization according to the training load of some physiological and biochemical variables of badminton players and runner800 m youth
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It is necessary to use the means of recovery and other means that help to get rid of the effects of fatigue, as the game of badminton and the effectiveness of running 800 meters fall within the mixed system with the superiority of the anaerobic system by more than the air system, so requires the development of energy systems In proportion to the time of the match for badminton players and their travels and high performance and ability to tolerate the high level of lactic acid in the muscles and blood and increase the pain associated with the fatigue that occurs during the performance. In light of the physical and physiological processes of these actions N it should seek through training programs to develop your endurance and wind energy sys

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Publication Date
Wed Jan 01 2025
Journal Name
Aip Conference Proceedings
Synthesis and evaluation of chalcone derivatives for antimicrobial and antioxidant activities using microwave-assisted methodology
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Publication Date
Tue Jun 20 2023
Journal Name
Baghdad Science Journal
Synthesis and Evaluation of Platinum Nanoparticles Using F. Carica Fruit Extract and Their Antimicrobial Activities
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Abstract

In this manuscript, a simple new method for the green synthesis of platinum nanoparticles (Pt NPs) utilizing F. carica Fig extract as reducing agent for antimicrobial activities was reported. Simultaneously, the microstructural and morphological features of the synthesized Pt NPs were thoroughly investigated. In particular, the attained Pt NPs exhibited spherical shape with diameter range of 5-30 nm and root mean square of 9.48 nm using Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM), respectively. Additionally, the final product (Pt NPs) was screened as antifungal and antibacterial agent against Candida and Aspergillus species as well as Gram-positive Staphyllococcus aureus and G

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Publication Date
Tue Jun 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Phosphorus Removal from Water and Waste Water by Chemical Precipitation Using Alum and Calcium Chloride
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Phosphorus is usually the limiting nutrient for eutrophication in inland receiving waters; therefore, phosphorus concentrations must be controlled. In the present study, a series of jar test was conducted to evaluate the optimum pH, dosage and performance parameters for coagulants alum and calcium chloride. Phosphorus removal by alum was found to be highly pH dependent with an optimum pH of 5.7-6. At this pH an alum dosage of 80 mg/l removed 83 % of the total phosphorus. Better removal was achieved when the solution was buffered at pH = 6. Phosphorus removal was not affected by varying the slow mixing period; this is due to the fact that the reaction is relatively fast.
The dosage of calcium chloride and pH of solution play an importa

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Publication Date
Thu Jun 01 2023
Journal Name
Baghdad Science Journal
Design and construction of anair pollution detection system using a laser beam and absorption spectroscopy
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Air pollution is one of the important problems facing Iraq. Air pollution is the result of uncontrolled emissions from factories, car exhaust electric generators, and oil refineries and often reaches unacceptable limits by international standards. These pollutants can greatly affect human health and regular population activities. For this reason, there is an urgent need for effective devices to monitor the molecular concentration of air pollutants in cities and urban areas. In this research, an optical system has been built consisting of aHelium-Neonlaser,5mWand at 632.8 nm, a glass cell with a defined size, and a power meter(Gentec-E-model: uno) where a scattering of the laser beam occurs due to air pollution. Two pollutants were examin

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