A linear and nonlinear theoretical and experimental aeroelastic investigation of a wing-flap-tab typical section model undergoing two-dimensional incompressible airflow is described. The linear flutter velocity (LFV) and frequency are predicted using linear analysis. Then a freeplay structural nonlinearity is considered in the tab. The structural equations of motion have been coupled with Theodorsen aerodynamic theory to produce the theoretical aeroelastic model which is analyzed by a state space method to predict the LFV and flutter frequency. Linear piecewise function has been used to introduce the tab spring stiffness in the freeplay state. The ground vibration test is used to measure the model structural dynamic characteristics. Then the experimental aeroelastic model is placed in a low speed wind tunnel to measure the LFV and the limit cycle oscillation (LCO) of the physical model induced by freeplay. The root main square amplitude value of the pitch, flap pitch, tab pitch and plunge degrees of freedom of the tab nonlinearities are normalized with freeplay gap size to produce a bifurcation diagram with normalized airflow velocity as the bifurcation parameter. The results show that the LCO frequency jumps from low to high frequency at a yet higher flow velocity. At the same flow velocity, the pitch and plunge motion response amplitudes drop while the flap pitch and tab pitch degrees of freedom response amplitude increase. In general the experimental measured LCO is more complicated than the theoretically calculated LCO in terms of the harmonic content of the response. On the other hand there is good agreement between the theoretical and experimental result of the linear system as well the LCO for the tab freeplay nonlinearities
Two field experiments were conducted during the season 2021-2022 in central Iraq represented by the Al-Muthanna governorate - Al-Majd District and Al-Qadisiyah governorate / Al-Nouriah Research Station to determine the productivity of the Baghdad 3 cultivar from spray foliar fertilization of Macro and Micro elements with alcoholic sugars and half the fertilizer recommendation for addition floor, three treatments were used for fertilization: T1 as the control treatment and T2 with alcoholic sugar fertilization at a concentration of 20 g.L-1 + the fertilizer combination of Macro and Micro elements, and T3 with alcoholic sugar fertilization at a concentration of 40 g.L-1 + the fertilizer combination of Macro and Microelements, at irrigation 55
... Show MoreIn this study, the response and behavior of machine foundations resting on dry and saturated sand was investigated experimentally. In order to investigate the response of soil and footing to steady state dynamic loading, a physical model was manufactured to simulate steady state harmonic load at different operating frequencies. Total of 84 physical models were performed. The footing parameters are related to the size of the rectangular footing and depth of embedment. Two sizes of rectangular steel model footing were tested at the surface and at 50 mm depth below model surface. Meanwhile the investigated parameters of the soil condition include dry and saturated sand for two relative densities 30% and 80%. The response of the footing was ela
... Show MoreTest results of nine reinforced concrete one way slab with and without lacing reinforcement are reported. The tests were designed to study the effect of the lacing reinforcement on the flexural response of one way slabs. The test parameters were considered is the lacing steel ratios of (0, 0.0025, 0.0045, and 0.0065), flexural steel ratios of (0.0025, 0.0045, and 0.0065) and span to the effective depth ratios of (11, 13, and 16). Two specimens had no lacing reinforcement and the remaining seven specimens had the lacing reinforcement. Four point bending test were carried out, one of the specimens was tested under the static load applied gradually up to failure and the other specimens were tested under repeated load (5 cyc
... Show MoreThe 2011 Iraqi Measles Control Campaign had as its aim to improve immunization coverage among young adults' 17-24years and, in the longer term, prevention of measles epidemics. The aim of the study is estimation measles vaccination and revaccination efficacy by evaluate the seroprevalence of antibody and response to reimmunization in young adults. A previously vaccinated 189 young adult medical students were tested for measles specific IgG &IgM pre and post catch-up revaccination by using commercially available ELISA. To assess the seroprevalence of antibody response pre measles reimmunization in previously vaccinated young adults; 45 were found to be seronegative. To differentiate between primary and secondary vaccine failure, anti- mea
... Show MoreIndividual cannot live alone due to to his need for others to facilitate His supplies for living, thus social affiliation is considered one of the most important psychological, social needs in individuals life through his willing to affiliate to others whether they were friends ,family, colleague , or even home to reach some degree of psychological stability.
Affiliation is a tool to search for Satiate through living with group from the same type or comply for group or to be compatible with them or even to be adherent and accept what the group agreed about of criterion.
 
... Show MoreThe aim of the research is to identify the international accounting standards and accounting standards for Islamic banks, and to analyze the most important problems in the application of Islamic accounting standards, as well as to analyze some of the principles and methods used in the application of accounting standards in Islamic banks. The research was built on three hypotheses, the first being (there is a tangible impact on the application of international accounting standards for banks’ management of liquidity, achieving profits, maintaining property rights and fulfilling their obligations), and the second (the bank facing obstacles using Islamic accounting standards, as it is expected that when using Islamic accounting standar
... Show MoreThe objective of this article is to delve into the intricate dynamics of marriage relationships, exploring the impact of emotions such as fear, love, financial considerations and likability. In our investigation, we adopt a perspective that acknowledges the nonlinear nature of interactions among individuals. Diverging from certain prior studies, we propose that the fear element within the context of marriage is not a singular, isolated factor but rather a manifestation resulting from the amalgamation of numerous social issues. This, in turn, contributes to the emergence of strained and unsuccessful relationships. Unlike conventional approaches, we extensively examine the conditions essential for the existence of all socially signifi
... Show More