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Comparative study of vibration analysis in rotary shafts between Rayleigh's and Dunkerley's methods
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The importance of vibrations in rotating rotors in engineering applications has been examined, as has the best approach to interpreting vibration data. The most extensively used analytical approaches for rotating shaft vibration analysis have been investigated. In this research, a detailed study was made of the Rayleigh and Dunkerley methods due to their importance in the special calculations to find the amplitude of vibrations in the rotation system. The multi-node method was used to calculate both Dunkerley's and Rayleigh's methods. An experimental platform was built to study the vibrations that occur in the rotating shafts, and the results were compared with theoretical calculations and with different distances of the bearings. It proved that there is very little error between the experimental and theoretical results. The vibration signal from the sensors was analyzed using the LABVIEW program. Rayleigh's method was compared to the exact method, and it was considered the most accurate method. It was found that it made very little difference, up to about 0.06%. As for the Dunkerley method, the difference between it and the proper method is about 4%, which is acceptable. Then a comparison was made between Rayleigh's and Dunkerley's methods, and it was found that Dunkerley's method is the most appropriate in the calculations.

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Publication Date
Tue Dec 30 2025
Journal Name
Journal Of Baghdad College Of Dentistry
A Comparison of the Effectiveness of Reciprocating System with Continuous Rotary Systems in Non-Surgical Endodontic Retreatment (An In vitro study)
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Background: Optimal root canal retreatment was required safe and efficient removal of filling material from root canal. The aim of this in vitro study was to compare the efficacy of reciprocating and continuous motion of four retreatment systems in removal of root canal filling material. Materials and Methods: Forty distal roots of the mandibular first molars teeth were used in this study, these roots were embedded in cold clear acrylic,roots were instrumented using crown down technique and rotary ProTaper systemize Sx to size F2 ,instrumentation were done with copiousirrigation of 2.5% sodium hypochlorite and 17% buffered solution of EDTA was used as final irrigant followed by distilledwater, roots were obturated with AH26 sealer and Prota

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Publication Date
Sat Jun 01 2024
Journal Name
University Of Thi-qar Journal Of Agricultural Research
A comparative histological, histometrical and hormonal study between the ovary and uterus of non-pregnant and pregnant local breed cat (Catus felius)
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Samples of the ovary and uterus of local breed cats used to investigate the histological, histometrical and hormonal features. The paraffin embedding technique was used for processing of tissue that stained by hematoxyline and eosin stain, and massons trichrom stain. Ovary of at proestrus or oestrus phases composed of outer cortex that covered by cuboidal germinal epithelium and inner medulla. Tunica albuginea composed of a thin layer of characterized by fusiform stromal cells. The cortex content groups of Oogonial cells, numerous primordial follicles, little primary, secondary and tertiary follicles in addition for 1-2 follicular cysts and mature corpus letium. In pregnant cat the thickness of ovarian cortex was significantly incre

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Publication Date
Mon Jun 01 2015
Journal Name
Journal Of The College Of Languages (jcl)
An Analysis of Textual Themes in M.A Theses and Ph. D. Dissertations Written by Iraqi EFL Learners
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The present study investigates the realization and significance of textual themes in the organizational structure of M.A theses and Ph.D. dissertations, namely: the abstracts, introductions and conclusions, since in such parts the students depend on their own expressions, styles and constructions to express different viewpoints, plans, inferences, etc. The study also investigates the similarities and differences between M.A theses and Ph.D. dissertations concerning the use of textual themes;it sets out to conduct a detailed analysis of textual themes used in such texts. In conducting such an analysis, the study adopts Halliday's (1994) approach of textual themes. The results of such an analysis have clearly shown that, in spite of the di

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Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Analysis of the causal relationship between the gross fixed capital formation and gross domestic product for the agricultural sector for the period 1980 -2010
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Despite Iraq's possession of the energies material, human and agricultural resources and great economic but that contribution of the agricultural sector in the total gross fixed capital formation and gross domestic product in the Iraqi economy remained low and declining continuously since the nineties of the last century, as well as the inability of agricultural production to meet the country's needs of food . The food gap increased strategic food crops until it reached 1049 thousand tons in 2010. On this basis, there is a need to study and analysis the behavior of the function of  gross fixed capital format

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Publication Date
Tue Dec 30 2025
Journal Name
Revista Iberoamericana De Psicología Del Ejercicio Y El Deporte, Issn 1886-8576, Vol. 17, Nº. 6, 2022, Págs. 408-412
A Comparative Study In (resilience And Immunity) Psychological And The Level Of Skillful Performance In Some Ball Skills In Rhythmic Gymnastics Between Students Of The Second And Third Stages
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Autorías: Nuha Mohsin Dhahi, Muhammad Hamza Shihab. Localización: Revista iberoamericana de psicología del ejercicio y el deporte. Nº. 6, 2022. Artículo de Revista en Dialnet.

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Publication Date
Wed Oct 17 2018
Journal Name
Journal Of Economics And Administrative Sciences
comparison between the methods estimate nonparametric and semiparametric transfer function model in time series the Using simulation
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 The transfer function model the basic concepts in the time series. This model is used in the case of multivariate time series. As for the design of this model, it depends on the available data in the time series and other information in the series so when the representation of the transfer function model depends on the representation of the data In this research, the transfer function has been estimated using the style nonparametric represented in two method  local linear regression and cubic smoothing spline method The method of semi-parametric represented use semiparametric single index model, With four proposals, , That the goal of this research is comparing the capabilities of the above mentioned m

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Publication Date
Tue Jan 01 2019
Journal Name
Journal Of The College Of Languages (jcl)
A Critical Discourse Analysis of Hate Speech
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Online communication on social networks has become a never-given-up way of expressing and sharing views and opinions within the realm of all topics on earth, and that is that! A basis essential in this is the limits at which "freedom of expression" should not be trespassed so as not to fall into the expression of "hate speech". These two ends make a base in the UN regulations pertaining to human rights: One is free to express, but not to hate by expression. Hereunder, a Critical Discourse Analysis in terms of Fairclough's dialectical-relational approach (2001) is made of Facebook posts (being made by common people, and not of official nature)  targeting Islam and Muslims. This is made so as to recognize these instances of "speech" a

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Publication Date
Tue Dec 30 2025
Journal Name
Al–bahith Al–a'alami
Convincing methods in designing infographic content analytical study
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The research aims to reveal the recent trends used in providing information and to know the persuasive methods used in designing the content of the infographic as well as the nature of persuasive design methods and the topics presented by the infographic in the research sample.   The researcher used the survey method, specifically the survey, by using the content analysis method to analyze the infographic material from the sample selected from the press and news sites that are the subject of the research, based on the method of what was said? How was it said? The researcher relied on the intentional sample, and this sample depends on the researcher selecting the vocabulary of the sample based on experiences and evaluating the c

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Publication Date
Sat Jan 01 2022
Journal Name
Materials Today: Proceedings
Comparative study between the individual, dual and triple addition of (SF), (TGP) and (PVA) for improving Local Plaster of Paris (LPOP) properties
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Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
Comparative Development between the Asian Tiger Crisis and the Mortgage Crisis
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Financial crisis is one of the topics that have attracted the interest of researchers in recently. The research focused on the issue of the crisis of the Asian Tigers and the mortgage crisis and comparing them in terms of causes and repercussions. It may meet most of the financial crises in many of its causes, factors, roots and results in the advanced and the developing countries. This crisis has its own pattern and its causes and nature and it is characterized by a crisis of cash liquidity and the collapse of many banks and declare bankruptcy and a sharp decline in stock prices and indices of the stock market and so far the common denominators among the causes but does not mean this There are differences between the financial c

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