Many of mechanical systems are exposed to undesired vibrations, so designing an active vibration control (AVC) system is important in engineering decisions to reduce this vibration. Smart structure technology is used for vibration reduction. Therefore, the cantilever beam is embedded by a piezoelectric (PZT) as an actuator. The optimal LQR controller is designed that reduce the vibration of the smart beam by using a PZT element.
In this study the main part is to change the length of the aluminum cantilever beam, so keep the control gains, the excitation, the actuation voltage, and mechanical properties of the aluminum beam for each length of the smart cantilever beam and observe the behavior and effec
... Show MoreIn this study, plain concrete simply supported beams subjected to two points loading were analyzed for the flexure. The numerical model of the beam was constructed in the meso-scale representation of concrete as a two phasic material (aggregate, and mortar). The fracture process of the concrete beams under loading was investigated in the laboratory as well as by the numerical models. The Extended Finite Element Method (XFEM) was employed for the treatment of the discontinuities that appeared during the fracture process in concrete. Finite element method with the feature standard/explicitlywas utilized for the numerical analysis. Aggregate particles were assumedof elliptic shape. Other properties such as grading and sizes of the aggr
... Show MoreThis research investigated the importance and priorities of the project overhead costs in Iraq via a questionnaire using the fuzzy analytic hierarchy process technique (FAHP). Using this technique is very important in the uncertain circumstances as in our country. The researcher reached to frame an equation through the results of the priorities of weights include the percentages of each of the main items of the project overhead costs. The researcher tested this equation by applying it to one of the completed projects and the results showed suitability for the application. The percentages of the (salaries, grants, and incentives) and (fieldwork requirements) in equation represent approximately two-thirds of project overhe
... Show MoreA study of taxonomic quality of algae attaching Three concert bridges built on the Tigris River within city of Baghdad including Al-Jadriyah Bridge in Al-Jadriyah area and the Bab Al-Mu'adam Bridge in Al-Shalajiya area, while the third site included Al-Muthanna Bridge in north of Baghdad city, for the period from Autumn 2021 and Winter 2022. The study identified 114 species of 32 Genus in which the predominance of Bacillariophceae (74 species, 14 Genus) Followed by Cyanophyceae (30species, 12 Genus) and 10 species (6 Genus) of Chlorophyceae. The study showed an increase in species of Bacillariophceae, Cyanophyceae which has the ability to secretion gelatinous substances that enable it to stick to solid stand, the number of the larges
... Show MoreUrban land price is the primary indicator of land development in urban areas. Land prices in holly cities have rapidly increased due to tourism and religious activities. Public agencies are usually facing challenges in managing land prices in religious areas. Therefore, they require developed models or tools to understand land prices within religious cities. Predicting land prices can efficiently retain future management and develop urban lands within religious cities. This study proposed a new methodology to predict urban land prices within holy cities. The methodology is based on two models, Linear Regression (LR) and Support Vector Regression (SVR), and nine variables (land price, land area,
... Show MoreObjective: The current study aimed to prepare a measure for comprehensive knowledge marketing management. In the Iraqi sports institutions under study, identifying the extent of each dimension of comprehensive knowledge marketing management. Research methodology: This study relied on appropriate scientific methods, mainly represented by the descriptive method and the analytical method, and on the case study method because it suits the nature of the study. The study population was determined from the administrative cadres in the Iraqi Sports Federation, and the research sample numbered (86) and was represented as follows: The preparation sample numbered (50) and a percentage amounted to (58.13%), the sample of the exploratory experim
... Show MoreObjective: The current study aimed to prepare a measure for comprehensive knowledge marketing management. In the Iraqi sports institutions under study, identifying the extent of each dimension of comprehensive knowledge marketing management. Research methodology: This study relied on appropriate scientific methods, mainly represented by the descriptive method and the analytical method, and on the case study method because it suits the nature of the study. The study population was determined from the administrative cadres in the Iraqi Sports Federation, and the research sample numbered (86) and was represented as follows: The preparation sample numbered (50) and a percentage amounted to (58.13%), the sample of the exploratory experim
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