Fatigue failure is almost considered as the predominant problem affecting automotive parts under dynamic loading condition. Thus, more understanding of crack behavior during fatigue can strongly help in finding the proper mechanism to avoid the final fracture and extent the service life of components. The main goal of this paper is to study the fracture behavior of low carbon steel which is used mostly in automotive industry. For this purpose, the fractography of samples subjected to high and low stress levels in fatigue test then was evaluated and analyzed. Hardness and tensile tests were carried out to determine the properties of used steel. Also, the samples were characterized by microstructure test and XRD analysis to examine the constitute phases. The fatigue test (S-N curve) was done at stress ratio (R= -1), and the fracture examination was perform using Scanning Electron Microscope (SEM). The results of microstructure and XRD analysis were indicating that the Ferrite and a little amount of pearlite are the dominant phases of this steel. Whereas, the fractography observations reveal that the void coalescence ductile fracture is the main failure mode in samples with high stress level, while the ductile fracture (void coalescence) with Transgranular Cleavage fracture was noticed in low stress fatigue mode for this alloy.
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La question de la violence et de l'agressivité porte une importance remarquable dans l’esprit de Jean Genet qui estime le crime en le considérant comme beau. Il lui donne une valeur suprême. Il le glorifie avec ses personnages criminels. Le langage théâtral genétien est violent qui conduit à la fin à l’acte agressif, le crime et la mort. Ce théâtre qui aborde la condition humaine retrace sur la scène le chemin tragique de l’homme moderne.
... Show MoreThe focus of this research lies in the definition of an important aspect of financial development, which is reflected on the alleviation of poverty in Iraq, namely financial inclusion and then taking the path of achieving a sustainable economy, certainly after reviewing one of the important international experiences in this regard and finally measuring the level of financial inclusion in Iraq and its impact on poverty reduction through the absolute poverty line indicator.
Mixed-effects conditional logistic regression is evidently more effective in the study of qualitative differences in longitudinal pollution data as well as their implications on heterogeneous subgroups. This study seeks that conditional logistic regression is a robust evaluation method for environmental studies, thru the analysis of environment pollution as a function of oil production and environmental factors. Consequently, it has been established theoretically that the primary objective of model selection in this research is to identify the candidate model that is optimal for the conditional design. The candidate model should achieve generalizability, goodness-of-fit, parsimony and establish equilibrium between bias and variab
... Show Moreيواجه الكثير من الافراد مشكلات في التكيف، خاصة الطلبة الذين ينتقلون من المرحلة الدراسية الثانوية الى المرحلة الجامعية، حيث يرافق هذه البيئة الثقافية الاجتماعية العديد من الضغوط والمواقف التي تحتم على الطالب الوصول الى تكيف مثالي.
ان التعليم الجامعي يوفر مجالات عديدة للتخصص تعمل على تحقيق طموحات الشباب التي تناسب قدراتهم وميولهم واهتماماتهم، وهو بذلك يمثل نوعية من التعليم تختلف عن النم
... Show MoreThe trade war, of course, leads to a sharp tension in international relations because the economy is the lifeblood of the states. In the world of trade and economy, countries began to lean towards cooperation. Economic relations after World War II were more liberal, trade barriers were removed and global trade became more flexible and smooth
This research attempts to propose production and acquisition of scientific knowledge among the students of educational science faculties in some universities Governmental Jordanian (Yarmouk, Jordan, Muta). In addition to sources of educational gained in some of the Governmental Jordanian universities (Yarmouk, Jordan, Muta), and to propose the necessary socio-cultural dimensions of knowledge acquisition and production, using developmental screening method, which is represented in the study design tool (questionnaire), which consisted of 4 scales, scale: The reality of the acquisition of knowledge / reality of the production of knowledge / social dimensions of knowledge acquisition and production / cultural dimensions of knowl
... Show MoreThe research(the internal and external factors affecting the political system in
PAKISTAN) involves a series of effects interact both internally and external to affect the
stsbility of the political system.
Intrernally there are a lot of powers affecting the political map of PAKISTAN such as
military institution, political parties, judgement, religious schools……etc.of internal
factors, which represent one of the most important pressure points on the system.
Externally one of the most important external factors which affect internal stability is
Pakistani allision to USA in antiterrorism war. The Pakistani military institution was
involved in the war against Pakistani tribes leading to unstable security in Paki
The researchers have a special interest in studying Markov chains as one of the probability samples which has many applications in different fields. This study comes to deal with the changes issue that happen on budget expenditures by using statistical methods, and Markov chains is the best expression about that as they are regarded reliable samples in the prediction process. A transitional matrix is built for three expenditure cases (increase ,decrease ,stability) for one of budget expenditure items (base salary) for three directorates (Baghdad ,Nineveh , Diyala) of one of the ministries. Results are analyzed by applying Maximum likelihood estimation and Ordinary least squares methods resulting
... Show Moreلم يكن من السهولة على الباحث في مجال التربية والتعليم تحديد مراحل التعليم في العصر العباسي الأخير او وضع فواصل محددة بين تلك المراحل المختلفة من ذلك العصر، لان التعليم آنذاك كان يتميز بالمرونة التي تتيح للتعليم الحرية المطلقة في اختيار نوع الدراسة والمادة الدراسية التي يريد دراستها.
فكانت المساجد والكتاتيب والمجالس العامة والخاصة هي المؤسسات العلمية الاولى للتعليم عند المسلمين في عهد ال
... Show More- The study aimed to identify the position of the university leaders from the proposed abolition of the Ministry of Higher Education in Jordan as un approach for the development of society, the study relied descriptive method survey with the assistance consists of (33) items, and check validity and reliability of the instrument, and was applied to a sample of university leaders, (57) a leading university presidents and their assistants and deans and their assistants, and after processing the data bagful statistical( spss) overall results showed the to arithmetic average of (2.74) and the degree of medium and this means that most respondents moderately support the abolition of the ministry, the most prominent item that makes