This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity. A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness.
The cancer is one of the biggest health problems that facing the world . And the bladder cancer has a special place among the most spread cancers in Arab countries specially in Iraq and Egypt(2) . It is one of the diseases which can be treated and cured if it is diagnosed early . This research is aimed at studying the assistant factors that diagnose bladder cancer such as (patient's age , gender , and other major complains of hematuria , burning or pain during urination and micturition disorders) and then determine which factors are the most effective in the possibility of diagnosing this disease by using the statistical model (logistic regression model) and depending on a random sample of (128) patients . After
... Show MoreAfter the information revolution that occurred in the Western world, and the developments in all fields, especially in the field of education and e-learning, from an integrated system based on the effective employment of information and communication technology in the teaching and learning processes through an environment rich in computer and Internet applications, the community and the learner were able to access information sources and learning at any time and place, in a way that achieves mutual interaction between the elements of the system and the surrounding environment. After the occurrence of the phenomenon of Covid 19, it led to a major interruption in all educational systems that had never happened before, and the disrupt
... Show MoreThis paper aims to review the intellectual to the most important thought leaders administrative and strategic They both (Henry Fayol and Michelle Porter), who forward a lot of ideas that have helped countries in the advancement and progress their economies , has been drawing literature theoretical common border in Contributions ( Fayol ) philosophical and between applications ( Porter ), which reversed strategies of the three ( the leadership of the cost, differentiation, and focus ), so browse search how to apply and use the principles of Fayol in the implementation of strategies competitiveness of Porter, and stems from a problem ( ( to what extent a reflection of the principles ( Fayol) fourteen strategies (Porter ) competitiv
... Show MoreThe aim of the research is to identify the suitability of a patrol model in evaluating the financial performance of Iraqi banks. The financial reports of five Iraqi commercial banks were approved as a sample for research for the period from 2015 to 2020. The most common financial ratios were adopted for the purpose of measuring the five elements of the model, which are capital adequacy, profitability, credit risk, bankal efficiency and liquidity. The results showed the possibility of using the PATROL model in evaluating the performance of Iraqi banks, as it gave a realistic image of the reality of Iraqi banks in terms of high capital adequacy index and high liquidity, as well as fluctuation in profitability index, not to mention the prob
... Show MoreIn the presence of multi-collinearity problem, the parameter estimation method based on the ordinary least squares procedure is unsatisfactory. In 1970, Hoerl and Kennard insert analternative method labeled as estimator of ridge regression.
In such estimator, ridge parameter plays an important role in estimation. Various methods were proposed by many statisticians to select the biasing constant (ridge parameter). Another popular method that is used to deal with the multi-collinearity problem is the principal component method. In this paper,we employ the simulation technique to compare the performance of principal component estimator with some types of ordinary ridge regression estimators based on the value of t
... Show MoreMedia, especially press plays an important role in fighting corruption and tackling this phenomenon, which has become widespread in our society, through its effective role in raising awareness of the seriousness of spreading of corruption of all its forms in society.
All international conventions and agreements stress the necessity of the role of media and its importance in the light of corruption. All countries also commit themselves to the necessity of guaranteeing the freedom of media and the circulation of information and preparing it as a prerequisite for activating the People’s Control Mechanism and supporting measures and means to prevent and combat financial and administrative corruption more actively and effectively.
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As is known that the consumer price index (CPI) is one of the most important price indices because of its direct effect on the welfare of the individual and his living.
We have been address the problem of Strongly seasonal commodities in calculating (CPI) and identifying some of the solution.
We have used an actual data for a set of commodities (including strongly seasonal commodities) to calculate the index price by using (Annual Basket With Carry Forward Prices method) . Although this method can be successfully used in the context of seasonal&nbs
... Show MoreThe public budget is on the same time an art and a science .As an accountable science it seeks balance between public income and public expenditure for an accountable year. And as an accountable art it seeks to achieve economic balance by distributing equitable income in order to reach sustainable development .This is the optimal use of all natural and human resources to address scarcity of natural resources facing the increase need of human resources by spending on education, health, environment, housing, agriculture and industry to achieve social justice for the current generation and future generations. Since the first budget in Iraq on 1921 an accounting budget, is balancing the sections and items has been adopted and since the publi
... Show MoreThe importance of this research comes from the possibility of achieving positive interaction between accounting and tax through the interest in setting accounting standards and adapting them to local tax legislation, as the adoption of the application of the international standard (IAS 12) for income taxes helps to measure and determine the base for income tax and may lead to an increase in the tax outcome. Through the reliance of enterprises on many accounting bases, and that the tax administration in Iraq depends on the element of personal judgment in determining the tax base, which leads to lack of objectivity in determining the tax outcome, as the impact of the accounting standard (IAS 12) on the tax base and tax outcome is one of th
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