In this paper an attempt to provide a single degree of freedom lumped model for fluid structure interaction (FSI) dynamical analysis will be presented. The model can be used to clarify some important concept in the FSI dynamics such as the added mass, added stiffness, added damping, wave coupling ,influence mass coefficient and critical fluid depth . The numerical results of the model show that the natural frequency decrease with the increasing of many parameters related to the structure and the fluid .It is found that the interaction phenomena can become weak or strong depending on the depth of the containing fluid .The damped and un damped free response are plotted in time domain and phase plane for different model parameters It is found that the vibration free response is still sinusoidal for weak FSI coupling ,however for strong coupling it behaves as modulated periodic response .To justify some of the theoretical aspects such as; the effects of the fluid density and the interact shape on the natural frequency an experiment was conducted .The results of the experiment shows a good agreement with the theory where the error is not exceeded 7%.
Background: Toxoplasmosis is a very common infection caused by the obligate intracellular protozoan parasite. This parasite is called Toxoplasma gondii widely distributed around the world . Toxoplasma gondii can be vertically transmitted to the fetus during pregnancy and may cause wide range of clinical manifestations in the offspring.
Objective: To determine seroprevalence Immunoglobulin G (IgG) and Immunoglobulin M (IgM ) to toxoplasma gondii among pregnant women and to identify the risk factors.
Type of the study: A cross-sectional study.
Methods: A total of 110 blood samples of pregnant women were collected from
... Show MoreThe modern business environment has witnesses tremendous developments as a result of the globalization of markets and economic openness and technological as well as the acquisition of the issue of corporate governance of great importance regarding it as one of the global innovations trends of control provisions on the management of companies as result of these developments ,increasing on competition between economic unit ,thus a decrease in market share because they do not take into account the response to the requirements of customers ,which kept her to search a modern management accounting methods to help them keep up with the changes and the availability of information for the various adminis
... Show MoreAbstract The Object of the study aims to identify the effectiveness of using the 7E’s learning cycle to learn movement chains on uneven bars, for this purpose, we used the method SPSS. On a sample composed (20) students on collage of physical education at the university of Baghdad Chosen as two groups experimental and control group (10) student for each group, and for data collection, we used SPSS After collecting the results and having treated them statistically, we conclude the use 7E’s learning cycle has achieved remarkable positive progress, but it has diverged between to methods, On this basis, the study recommended the necessity of applying 7E’s learning cycle strategy in learning the movement chain on uneven bar
... Show MoreThis study deals with the Spatial and Periodical Variation of the Economical Activities for the
Population of Al – Anbar Province on the level of districts , according to the Population
Computation for the period 1987 and 1997 and the results of determinations and numberings
for the year of 2011 .
This study depends on the Details Classifications of the 17th Activities for 1997 and 2011
beside the Triple Classification of the Economical Activities for the three study years .
The study proves that there is a spatial and periodical variation on the level of study area , and
that’s because of many factors , one of the most important of them was the distribution of
economical siege, as well as the weakness of the
To demonstrate the effect of changing cavity length for FM mode locked on pulse parameters and make comparison for both dispersion regime , a plot for each pulse parameter as Lr function are presented for normal and anomalous dispersion regimes . The analysis is based on the theoretical study and the results of numerical simulation using MATLAB. The effect of both normal and anomalous dispersion regimes on output pulses is investigate Fiber length effects on pulse parameters are investigated by driving the modulator into different values. A numerical solution for model equations using fourth-fifth order, Runge-Kutta method is performed through MATLAB 7.0 program. Fiber length effect on pulse parameters is investigated by driving th
... Show MoreThe aim of this paper is to find out the effects of the strategy of productive thinking upon the student’s achievement for the subject of research methodology in the College of Islamic Sciences. Achieving this objective, the researchers set the null hypotheses: (1) No difference is noticed to be statistically significant at the level of significance (0.05) among the student’s mean scores in the experimental group who were taught by the strategy of productive thinking, and the student’s mean scores in the control group who studied by the traditional method in the achievement test. (2) At level of sig. (0.05), there is no statistically significant difference in the mean of scores of the pre-tests and post ones in the achievement test of
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