In this research the natural frequency of a cracked simple supported beam (the crack is in many places and in different depths) is investigated analytically, experimentally and numerically by ANSYS program, and the results are compared. The beam is made of iron with dimensions of L*W*H= (0.84*0.02* 0.02m), and density = 7680kg/m3, E=200Gpa. A comparison made between analytical results from ANSYS with experimental results, where the biggest error percentage is about (7.2 %) in crack position (42 cm) and (6 mm) depth. Between Rayleigh method with experimental results the biggest error percentage is about (6.4 %) for the same crack position and depth. From the error percentages it could be concluded that the Rayleigh method gives close results to experimental than ANSYS. Also it is found that the frequency of beam when the crack is in the middle position is less than the frequency with crack near the end position.
It is proposed and studied a prey-predator system with a Holling type II functional response that merges predation fear with a predator-dependent prey's refuge. Understanding the impact of fear and refuge on the system's dynamic behavior is one of the objectives. All conceivable steady-states are investigated for their stability. The persistence condition of the system has been established. Local bifurcation analysis is performed in the Sotomayor sense. Extensive numerical simulation with varied parameters was used to explore the system's global dynamics. A limit cycle and a point attractor are the two types of attractors in the system. It's also interesting to note that the system exhibits bi-stability between these 2 types of attractors.
... Show MoreAfter the year 2003, Iraq went through multiple waves of violence and at different levels on the security, intellectual, political and social levels. Behind that stood several motives and incentives to enable violence that represented the first axis of research, the most important of which was the political motives that circulated an atmosphere that politics against society and transformed power into a field of political brutality against the individual and the group at once. There are also cultural, intellectual, media and economic motives such as weak cultural independence, poverty, marginalization, unemployment and want, and the absence of a media discourse that rejects violence but incites it, on the other ha
... Show MoreSchiff bases, named after Hugo Schiff, are aldehyde- or ketone-like compounds in which the carbonyl group is replaced by imine or azomethine group. They are widely used for industrial purposes and also have a broad range of applications as antioxidants. An overview of antioxidant applications of Schiff bases and their complexes is discussed in this review. A brief history of the synthesis and reactivity of Schiff bases and their complexes is presented. Factors of antioxidants are illustrated and discussed. Copyright © 2016 John Wiley & Sons, Ltd.
In general, the importance of cluster analysis is that one can evaluate elements by clustering multiple homogeneous data; the main objective of this analysis is to collect the elements of a single, homogeneous group into different divisions, depending on many variables. This method of analysis is used to reduce data, generate hypotheses and test them, as well as predict and match models. The research aims to evaluate the fuzzy cluster analysis, which is a special case of cluster analysis, as well as to compare the two methods—classical and fuzzy cluster analysis. The research topic has been allocated to the government and private hospitals. The sampling for this research was comprised of 288 patients being treated in 10 hospitals. As t
... Show Moreالتعددية الثقافية هي مفهوم يتعلق بالمجتمعات التي تضم ثقافات عده، أو العالم الذي يتضمن ثقافات متنوعة؛ فالتعددية هي التنوع الثقافي والفكري؛ وبالتالي هي عنصر إثراء للإنسانية وأساس لوجودها؛ فالتعددية الثقافية تتضمن القبول بالثقافات والافكار الانسانية كلها، وإفساح المجال أمامها للمشاركة في بنا ء الثقافة والفكر العالمي؛ وهكذا فإنها تتمثل في التسامح مع الثقافات والافكار المختلفة الاعتراف بالهويات والخصوصيات
... Show MoreThe present study deals with the social work and the social problems which
the Elderly who lives in the house of special needs suffer from . this study aims to
shed light to the most important social problems which they suffer from inside and
show their relationship and interaet with each ofher and what we can see about that
intereact either negative or positive relationship . Its scientific importance include
adding a new study in the field of take care of the Elderly . and that will enrich the
scientific field with agood knowledge . Becouse the studies in this part was little ,
but the scientific and practical importance of this study presents by the results and
specify of the important problems . In addition to
The current research that entitled (t Technical Experimentation incontemporary plastic arts) deals with study in used techniques and the material's functioning and its variations in artwork.It present the following questions :- 1-Does technical experimentation for mate an important phenomenon in contemporary art.2-Does technical experimentation construct an ability in creating new constructive and formative achievement in plastic art ?.The research includes three chapters . the first one deals with the problem of the research and its limits with the specification of terms . the second chapter present the technical Experimentation in contemporary plastic art with shapes display . the third chapter involves conclusions with discussions . t
... Show Moreشغلت نظرية العدل الإلهي بال الأديب العراقي القديم، مما جعلته يثير عبر نصوصه الأدبية كثير من التساؤلات حول عدالة الإلهة، التي يعبدها ويقدم لها الهدايا وتساؤلاته هذه دفعت بالباحث إلى اختيارها عنوانا لموضوعه، إلا أن الدراسة ستختصر على نصوص معينة، والسبب في ذلك أنها كانت الرائدة في هذا الجانب، وفي اللحظة التي ينتقي فيها العدل الإلهي وتتحول الإلهة إلى كلاب تلهث وراء غرائزها، ذهبنا وراء الأسباب التي قادت إلى فقد
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