This study focuses on the modeling of manufactured damper when used in steel buildings. The main aim of the manufactured dampers is to protect the steel buildings from the damaging effects that may result due to earthquakes by introducing an extra damping in addition to the traditional damping.
Only Pure Manufactured Dampers, has been considered in this study. Viscous modeling of damping is generally preferred in structural engineering as it leads to a linear model then it has been used during this study to simulate the behavior of the Pure Manufactured Damper.
After definition of structural parameters of a manufactured damper (its stiffness and its damping) it can be used as a structural element that can be added to a mathematical model of the structure. As the damping of manufactured dampers is generally greater than the damping of traditional materials, then the resulting damping matrix for the whole structure will be classified as a nonclassical damping. As most of literature on earthquake engineering have been written in terms of terminology related to mode superposition method and as this method is applicable to classical damping only. Then, this study tried to check the accuracy of the mode superposition method when applied to a structure with manufactured dampers. In this checking, approximated results of mode superposition method have been compared with more accurate results of direct integration method. From this comparison, it has been noted that the mode superposition method has different levels of accuracy depending on the relation between the fundamental
frequency of the structure and the dominate frequency of the earthmotion. If the frequency of the structure is approaching to a dominate frequency of the earthmotion, then the damping effect will be important and the difference between the direct integration method and the model superposition method is increasing and vice versa
The photonconductor detectors CdSe:Cu was fabricated as a thin film of (1 μm) in thickness using vacuum evaporation technique. doping with copper was made using vacuum annealing at 350oC under argon atmosphere . The spectral responsivity and spectral detectivity of the detector were determined as a function of incident wavelength on the sample. A remarkable improvement in performance was absorbed for the specimen, which doping with (1-5 wt%) Cu.
The spectral response increases with increasing of wavelength for incident radiation to maximum value, after that , it reduced sharply . There is a shifting for peak responsivity indirect of higher wavelength. The detectivity was increased with doping but its decreased as the concentration in
Investigation of the adsorption of acid fuchsin dye (AFD) on Zeolite 5A is carried out using batch scale experiments according to statistical design. Adsorption isotherms, kinetics and thermodynamics were demonstrated. Results showed that the maximum removal efficiency was using zeolite at a temperature of 93.68751 mg/g. Experimental data was found to fit the Langmuir isotherm and pseudo second order kinetics with maximum removal of about 95%. Thermodynamic analysis showed an endothermic adsorption. Optimization was made for the most affecting operating variables and a model equation for the predicted efficiency was suggested.
Aim The aim of this study is to evaluate the effect of demographic, clinical, and radiographic factors on the duration of surgical extraction of impacted lower third molars. Materials and methods This retrospective study included patients who underwent surgical removal of impacted lower third molars, and the investigated factors were demographic data including age and gender, radiographic data including the impacted tooth angulation and depth of impaction and ramus relation, and clinical data including the state of eruption of the impacted teeth. These factors were evaluated for association with the duration of surgery. Descriptive statistical analysis included percentages and mean ± standard deviation (SD). Student's t-test was used to co
... Show MoreThis study aimed to conduct a comparative analysis of seven calliphorid species of third- instar larvae that were collected from central Iraq. The purpose was to morphologically characterize these species and develop an identification key to differentiate them from closely related species. Scanning Electron Microscope (SEM) graphical images and high-resolution traditional optical microscopes were used to analyze the morphological characteristics of the species Calliphora vomitoria (Linnaeus, 1758), C. vicina Robineau-Desvoidy, 1830, Chrysomya albiceps (Widemann, 1819), Ch. rufifacies (Macquart, 1844), Ch. megacephala (Fabricius, 1794), Lucilia cuprina (Wiedemann, 1830), and L. sericata (Meigen, 1826). An identification key was const
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The teacher is the most able to achieve the goals of education in education because he has the ability to affect the behavior of the disciples testified and its actions and appearance and other actions that convey pupils with it sometimes in a manner unconscious or unconscious , and the importance of the role of the teacher in the educational process , it is necessary to compromise the care and attention to the extent that commensurate with the important role that the rise in the preparation of youth and composition , and as a result is needed to continue efforts to improve the quality of teacher preparation so that it can be more effective and positive in the educational process .
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The electron mirror phenomenon has been explored to describe the behavior of a probing electron trajectory inside the chamber of scanning electron microscope (SEM). This investigation has been carried out by means of the modulated mirror plot curve technique. This method is based on expanding sample potential to a multipolar form to detect the actual distribution of the trapped charges. Actually an experimental result is used to guiding results of this work toward the accurate side. Results have shown that the influence of each type of multipolar arrangement (monopole, dipole, quadruple, octopole … etc.) mainly depends on the driving potential.
Allium ampeloprasum extract has the potential to facilitate wound healing due to its anti-inflammatory, antioxidant, and antibacterial properties. In this study, we aimed to investigate the potential wound-healing activity of the methanol extract derived from Allium ampeloprasum. Using 30 healthy male Wester rats; control group: 15 rats; normal saline applied locally instead of plant-extract. Experimental group: 15 rats received a daily local application of 200 mg/kg of the plant extract. Then, for each healing period of 0, 5, or 10 days, each group was divided into three-subgroups: A, B, and C, each with five rats. There was a significant difference in the percentage of wound contraction between the control and experimental groups (p 0.02)
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