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
Thu Jan 04 2018
Journal Name
Journal Of Global Pharma Technology
A First Record and Developmental Stages of an Exotic Species Cochlicellabarbara (Linnaeus, 1758) (Gastropoda-Cochicellidae) in Iraq Baghdad
...Show More Authors

The aim of this study is to highlight this species of gastropoda Cochlicellabarbara( Linnaeus, 1758), which is recorded for the first time in Iraq, which is an exotic animal in this country. It is a terrestrial Molluscan, the study for three months (February, March and April) 2017. In garden houses in Baghdad Al-Karkh, we studied the development stages from the egg to the adult, they lay a hundred of eggs in about (15-20) eggs in each gelatinous sac, the shell with 7 whorls and about 10 mm in length.

Publication Date
Wed Mar 15 2023
Journal Name
Journal Of Tikrit University For Humanities
The Egyptian-Chinese Consensus at the Bandung Conference and Its Impact on Strengthening Relations between Them in 1955
...Show More Authors

كان المؤتمر الآسيوي الأفريقي الأول الذي عُقد في مدينة باندونغ الاندونيسية عام 1955 هو المؤتمر هو الأول الذي اجتمعت فيه الدول الآسيوية والأفريقية بعد الحرب العالمية الثانية. كان مؤتمر باندونغ بمثابة نقطة الانطلاق نحو تأسيس حركة عدم الانحياز، والتي كانت مصر أحد أبرز أقطابها. شهد المؤتمر تقاربا في الآراء ووجهات النظر بين جمهورية مصر العربية وجمهورية الصين الشعبية، لا سيّما وإن الحكومة المصرية كانت قد تبنت س

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Dec 01 2013
Journal Name
Journal
The Effects Of Pbl On Understanding Of Thermodynamics, Group Work And Self-Directed Learning Skills Among Physics Undergraduates
...Show More Authors

The aim of this study is to compare the effects of three methods: problem-based learning (PBL), PBL with lecture method, and conventional teaching on the understanding of thermodynamics, group work and self-directed learning skills among physics undergraduates. The actual sample size comprises of 122 students, who were selected randomly from the Physics Department, College of Education in Iraq, for academic year 2011-2012. In this study, the pre and posttest were done and the instruments were administered to the students for data collection. Inferential statistics were employed to analyze data. The independent variables were the PBL, the PBL with lecture method, and the conventional teaching. Dependent variables of statistical analysis were

... Show More
Publication Date
Sat Nov 10 2018
Journal Name
Oriental Journal Of Chemistry
New Series of Substituted Heterocyclics Derived from α , β – Unsaturated Ketone and Their Cytotoxic Activity Tumor Cell Lines
...Show More Authors

The aldol condensation of 2-acetylnaphthalene with 9-anthracene carboxaldehyde afforded α, β-unsaturated keton (1) . New heterocyclic compounds containing: cyclohexenone[2], indazole[3], pyrimidinethion [4], thiazolo fused pyrimidine[5], isoxazoline[6], substituted pyrazoline[7]a-d and pyrimidinone[8] rings system were synthesized from α, β-unsaturated keton[1]. Cyclization of [1] with ethylacetoacetate gave the mentioned heterocycle cyclohexanone [2]. The cyclo condensation of [2] with hydrazine gave the new indazole derivative [3]. furthermore, the reation of [1]with thiourea gives thiopyrmidine derivative [4]. The cyclo condensation of [4] with chloroacetic acid gave the fused rings [5]. Then reacted compound[1] with hydroxy

... Show More
View Publication Preview PDF
Crossref (1)
Clarivate Crossref
Publication Date
Wed Mar 01 2017
Journal Name
Journal Of Al-nahrain University-science
Cytological Effects of Mutagenic Agents and NaCl on Mitotic Division in Two Iraqi Rice (Oryza sativa L.) Genotypes
...Show More Authors

This study was carried out to determine the effects of NaCl (0.00, 50, 100, 150, 180 or 200) mM and two different types of mutagens chemical mutagen ethyl methyl sulphonate (EMS) at 0.5% and physical mutagen UV-B irradiation (40 min time exposure), on mitotic division in two Iraqi rice genotypes Amber 33 (A33) and Amber Baghdad (AB). Different concentrations of NaCl were used. Mitotic index (MI %) was decreased significantly by increasing NaCl concentration, however the highest mitotic index was recorded in mutated genotypes with EMS and UV-B. Different abnormal chromosomes were noticed in mutated plants. Results showed high percentage of abnormal chromosomes in EMS mutated genotypes. In addition no significant differences between genotypes

... Show More
View Publication
Crossref
Publication Date
Fri Mar 06 2026
Journal Name
Journal Of Baghdad College Of Dentistry
An Impairment of Salivary Gland Function in Rheumatoid Arthritis: Association with Change in Salivary Biomarkers and Disease Activity
...Show More Authors

Background: Rheumatoid arthritis is a chronic inflammatory autoimmune disease characterized by joint inflammation, involvement of exocrine salivary and lacrimal glands may occur as extra-articular mani¬festations in this disease. This study aimed to provide evidence of altered in function and composition of salivary gland in patients with rheumatoid arthritis by determine salivary flow rate and some biochemical parameters(total protein, amylase, peroxidase) and to investigate the relationship between disease activity and changes in function and composition of salivary gland. Materials and Methods: Fifty five patients with RA (7 males and 48 females) were enrolled in this study with age range (20-69) years. The patients were separated int

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 02 2019
Journal Name
Journal Of Educational And Psychological Researches
The Vision and Reality of Quality Standards in College Of Education / Ibn Al-Haytham from university teachers' perspective
...Show More Authors

The problem of research is that the colleges of education in general and the College of Education in particular continue to follow traditional administrative patterns and that there is a complaint that the educational outputs do not match the aspirations of the society and its future directions. The aim of the research is to identify the reality of quality assurance standards in the college and to create a future vision for these standards to apply them. The researcher has designed a questionnaire based on the responses of the research sample which consisted of a group of university teachers to identify the quality assurance standards. The findings revealed that it is necessary to find a clear approach to apply the standards of quality i

... Show More
View Publication Preview PDF
Publication Date
Fri Mar 06 2026
Journal Name
Journal Of Physical Education
Consecutive Case Study of Detraining On Some Functional, Physical, Body and Compound Skills Variables In Advance Basketball Players
...Show More Authors

View Publication
Publication Date
Wed Jun 15 2022
Journal Name
Malaysian Journal Of Science
STUDY THE RELATIONSHIP BETWEEN BREMSSTRAHLUNG DOSE RATE AND THE ENERGY OF BETA RAY FOR DIFFERENT TYPES OF SHIELD
...Show More Authors

The dose rate for bremsstrahlung radiation from beta particles with energy (1.710) MeV and (2.28) MeV which comes from (32P and 90Y) beta source respectively have been calculated through six materials (polyethylene, wood, aluminum, iron, tungsten and lead) for first shielding material with thickness (x=1) mm which are putting between beta sources and second shield (polyethylene, aluminum and lead) with thickness (1, 2 &4) mm have been calculated. The distance between beta source and second shield is constant (D=1) cm. This dose rate was found by program called Rad Pro Calculator (version 3.26). The results of dose rate of beta particles were plotted as a function to the atomic number (Z) for first shield materials for each

... Show More
Preview PDF
Publication Date
Sat Oct 01 2022
Journal Name
Baghdad Science Journal
Genotypes Diversity and Virulence Factor screening of Trichomonas vaginalis Isolated from Pregnant Women in Mosul (North of Iraq)
...Show More Authors

Trichomonas vaginalis is a causative agent of trichomoniasis , one of the most common non-viral sexually transmitted disease (STD) over all the world, especially in immunocompromised women such as pregnant. Wet smear and Giemsa stain are the current methods used in hospital to diagnosis trichomoniasis. DNA based diagnosis is still to be validated to diagnose the local isolates, the objective of the present study was to compare the conventional methods of disease diagnosis with the DNA-based method to diagnose Trichomonas incidence in local isolates. In the present study, 105 samples were collected from outpatient women (18-45 years) of Maternity hospital in Mosul who showed a classical presentation of Trichomonas

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (1)
Scopus Clarivate Crossref