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.
Steganography is a mean of hiding information within a more obvious form of
communication. It exploits the use of host data to hide a piece of information in such a way
that it is imperceptible to human observer. The major goals of effective Steganography are
High Embedding Capacity, Imperceptibility and Robustness. This paper introduces a scheme
for hiding secret images that could be as much as 25% of the host image data. The proposed
algorithm uses orthogonal discrete cosine transform for host image. A scaling factor (a) in
frequency domain controls the quality of the stego images. Experimented results of secret
image recovery after applying JPEG coding to the stego-images are included.
مشكلة البحث
وتعد مرحلة المراهقة من اصعب المراحل التي يمر بها الفرد واخطرها اذ يطلق عليها بمرحلة التفكير المجرد ، وهي مرحلة حاسمة في حياته اذ تتكون لديه معالم الشخصية .أنهم خزين الامة الحقيقي من الطاقات الحيوية التي لا تنضب لذا يجب الاهتمام بهذه الشريحة من المجتمع وتطويرهم وتوجيههم لاسلم الطرق للحفاظ على مستقبلهم ومستقبل الا
... Show MoreWhat linguists mentioned about the infinitive and its use in the linguistic levels of speech, whether with its verb, or what was mentioned in the difference between the infinitive and the noun of the source, are matters that are related to the phenomenon of hearing in speech, a need necessitated by the nature of the linguistic law
مشكلة البحث واهميته:-
اخذ موضوع العولمة قدراً وافياً من الاهتمام سواء على المستوى الاكاديمي او على مستوى اجهزة الاعلام والرأي العام ومختلف التيارات السياسية والاقتصادية والاجتماعية ، فلا يخلو أي لقاء اقتصادي او سياسي او اجتماعي من الحديث عن العولمة اذ نشرت العديد من الابحاث والدراسات وعقدت الكثير من الندوات والمؤتمرات لدراسة العولمة وبيان اثارها ولعل ذل
... Show MoreWith the growing use of electronic commerce has worked many companies, especially public shareholding to take advantage of them treated in the trade, so that the e-commerce part of the corporate environment, and this has made a career of accounting and auditing facing new challenges to the sophistication of the information and the rapid growth in the market for electronic commerce. And raised many questions about the ability of the audit profession to facing these challenges and how to audit operations of e-commerce and how to give confidence on websites, this sense it has become necessary keep the internal control systems of this technology and what has caused changes to the accounting system, and evolve to fit the developments that hav
... Show MoreThe searchers opinions are variant in determining the extent of impacting political risk in the host country on foreign direct investment decision. (Aharoni,1966) found, in his questionary study for group of foreign companies operating in India, that a political stability is one of the two most important factors, besides the market size, in the attraction of foreign investment, and its availability means that whether this specific country is good for foreign investment. On the other side, (Green and Benntt, 1972) are present a variant opinion to Aharonis opinion. They are reach to result state that a political instability do not impact on the general distribution of foreign i
... Show MoreAbstract search seeks to clarify the role and the importance of financial and fiscal policy adopted by the Iraqi Government during the years (2015 – 2018) to meet federal public deficit, as the Iraqi economy to shocks from falling global oil prices and terrorist attack ISIS, so the State budget suffered from a severe lack of income as a result of its reliance on revenues from selling crude oil and in return the high proportion of public expenditures. Especially military to counter these attacks that by studying the results of the implementation of budgets and analysis and statement Causes of disabilities and assessment of these policies and procedures imposed by the International Monetary Fund. the research aims to show how increased g
... Show MoreIn this work, an explicit formula for a class of Bi-Bazilevic univalent functions involving differential operator is given, as well as the determination of upper bounds for the general Taylor-Maclaurin coefficient of a functions belong to this class, are established Faber polynomials are used as a coordinated system to study the geometry of the manifold of coefficients for these functions. Also determining bounds for the first two coefficients of such functions.
In certain cases, our initial estimates improve some of the coefficient bounds and link them to earlier thoughtful results that are published earlier.
The paper presents the design of a system consisting of a solar panel with Single Input/Multiple Outputs (DC-DC) Buck Converter by using Simulink dialogue box tools in MATLAB software package for simulation the system. Maximum Power Point Tracking (MPPT) technique depending on Perturb and Observe (P&O) algorithm is used to control the output power of the converter and increase the efficiency of the system. The characteristics of the MSX-60 PV module is chosen in design of the system, whereas the electrical characteristics (P-V, I-V and P-I curves) for the module are achieved, that is affected by the solar radiation and temperature variations. The proposed design module has been found to be stable for any change in atmospheric tempera
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