In this paper, an analytical solution describing the deflection of a cracked beam repaired with piezoelectric patch is introduced. The solution is derived using perturbation method. A novel analytical model to calculate the proper dimensions of piezoelectric patches used to repair cracked beams is also introduced. This model shows that the thickness of the piezoelectric patch depends mainly on the thickness of the cracked beam, the electro-mechanical properties of the patch material, the applied load and the crack location. Furthermore, the model shows that the length of the piezoelectric patches depends on the thickness of the patch as well as it depends on the length of the cracked beam and the crack depth. The additional flexibility of the beam caused by crack is modeled depending on a dimensionless parameter identified from finite elements method. Different piezoelectric patches were designed and investigated using analytical and finite elements models. The results show that increasing the patch thickness enhances the beam resistance to crack and load effects, while increasing the length of the piezoelectric patch reduces the magnitude of the voltage required to repair the cracked beam.
Purpose – The main purpose of this research is to highlight the main role of strategic leadership skills for top managements in accessing to effective management in accordance with the (VUCA Prime) methodology in (VUCA) environment as Miniature virtual environment, which refers to (Volatility), (Uncertainty), (Complexity), and (Ambiguity).
methodology – To achieve the research objective, this study selected the quantitative approach in research design, Questionnaire was used as the main instrument for data collection, the sample comprised the opinion poll (106) individual who functions as a head department. (Structural equation modelling by (Smart Pls3)
... Show MoreThe evaluation of banks plays an important role in maintaining the interests of customers with the bank as well as providing continuous supervision and control by the Central Bank. The Central Bank of Iraq conducted an assessment of the Iraqi banks through the implementation of the CAMEL model during a certain period. This evaluation did not continue. The research provides continuity to the Central Bank's assessment and as a step to continue the evaluation process for all banks through the use of the CAMEL model. ROA and ROE by using the regression model for four Iraqi banks registered in the Iraqi market for securities during the period 2010-2016. The results showed that the capital and profitability indicators have a significan
... Show MoreThe novel was generally distinguished from other literary arts in its connection with the living reality as an imaginative practice that relies on political, economic, social, intellectual and cultural references and as a crucial tool in reading cultural references and dive deep into reality. As every novelist has a vision to embody this reality. As every novelist has a vision to embody this reality. The novel of ("Exceeded border by Hammed Al-Kafa’i) is a considered a fertile field for presenting social issues in their apparent structure and revealing the cultural patterns behind them which lies in its deep structure. The novel here moves its characters in its imaginary world in a way that it becomes more capable of adaptation and crysta
... Show MoreThe main goal of this in vivo study was to evaluate the effect of 532nm Q-switched Nd: YAG Laser in combination with Human Serum Albumin 20% concentration (as a welding aid) on the liver tissue repair clinically, and histologically. The animals used in this study were 21 male rabbits divided into three main groups: control group (3 rabbits), conventionally treated group (9 rabbits) and Laser treated group (9 rabbits). Each two main groups (conventional and laser treated) consist of three sub-groups depending on the response evaluation at three different periods. The Laser group was treated using 532nm Q-switched Nd: YAG laser after adding human serum albumin immediately on the incised liver’s tissue. The energy of was 460mJ, and 4Hz fr
... Show Moreالمواقف افي الدول العربية قراءة تحليلية في مواقف لدولية من التغيير (الولايات المتحدة - الاتحاد الاوروبي - روسيا)
The research aims at determining the main reason for the deterioration of the services and determining the correct method of distributing the funds to the administrative and administrative units. The discrepancy between the size of the financial allocations and the municipal services was the main research problem. Therefore, the researcher identified the gaps in municipal services by the concerned departments and compared them with The percentage of funds obtained through the work of a checklist for each of the directorates concerned. The researcher studied the specific criteria for these services, which were approved by the Ministry of Construction, Housing, Municipalities, and Public Works, and compared them wi
... Show MoreNumerical study is adapted to combine between piezoelectric fan as a turbulent air flow generator and perforated finned heat sinks. A single piezoelectric fan with different tip amplitudes placed eccentrically at the duct entrance. The problem of solid and perforated finned heat sinks is solved and analyzed numerically by using Ansys 17.2 fluent, and solving three dimensional energy and Navier–Stokes equations that set with RNG based k−ε scalable wall function turbulent model. Finite volume algorithm is used to solve both phases of solid and fluid. Calculations are done for three values of piezoelectric fan amplitudes 25 mm, 30 mm, and 40 mm, respectively. Results of this numerical study are compared with previous b
... Show MoreAbstract The wavelet shrink estimator is an attractive technique when estimating the nonparametric regression functions, but it is very sensitive in the case of a correlation in errors. In this research, a polynomial model of low degree was used for the purpose of addressing the boundary problem in the wavelet reduction in addition to using flexible threshold values in the case of Correlation in errors as it deals with those transactions at each level separately, unlike the comprehensive threshold values that deal with all levels simultaneously, as (Visushrink) methods, (False Discovery Rate) method, (Improvement Thresholding) and (Sureshrink method), as the study was conducted on real monthly data represented in the rates of theft crimes f
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