The paper presents an investigation to the flutter speed of composite wing for different ply orientation. Structurally the composite wing was idealized as a composite beam load carrying structure. Theodorsen’s expression was used to get the 2- dimension unsteady lifting force and pitching moment in the limit of incompressible flow and subsonic speed which were integrated over the wing span. A free vibration analysis was first carried out to get the natural frequencies and mode shapes .The velocity-damping (V-g) method was used to calculate the flutter speed and the flutter frequency. A wing of unmanned aerial vehicle was manufactured from woven glass and polyester resin where the flutter speed was calculated experimentally by the wind tunnel test .The flutter speed was calculated analytically for different ply orientation, it is found that the increasing in torsion rigidity leads to increase in the flutter speed, the fiber combination with high torsion rigidity and relatively low coupling rigidity give higher flutter speed.
In this paper, a novel flow control strategy which is the inlet throttled pump was used to design an angular velocity control system for rotary actuator. Inlet throttled systems have good performance in addition to their high efficiency compared to traditional valve-controlled systems. The flow in the proposed system is adjusted by a valve that is positioned at the pump inlet with the purpose of reducing the energy loses across the valve. This regulated flow is used then to control the actuator angular velocity. The system was modeled and the open loop stability and performance were studied. In order to improve the system performance, proportional-integral-derivative (PID) and H-infinity controllers have been designed. The multiplicative un
... Show MoreThe aim of the research is the knowing of the academic Scientific Journals of the colleges of University of Baghdad , through searching in the University of Baghdad website and the websites of colleges and thus studying the presentation of these journals in those website , and this is done by surfing the main pages of the websites for the colleges included in the research , and by analyzing the research made a menu for all the academic Scientific Journals for all institutes of the University of Baghdad , which simplifies the way for the researchers to publish these researches in the specific journals for their specialties .
The study aimed to increase the biological value of white bean. The effect of different concentrations 0.01 ,0.02,0.03,and 0.04 M of sodium sulfite solutions for 1hr at 70 ºC on the trypsin inhibitors activity, protein isolate and protein solubility of complete and dehulling white bean flour were studied.Trypsin inhibitors activity were reduced by 42.97, 58.69, 68.59 and 69.58% in complete white bean flour at 0.01 ,0.02, 0.03, 0.04 M respectively, while the corresponding values were 50.43, 61.00, 75.61 and 85.66% respectively in dehulling white bean flour .Protein isolate value was 13.41% and protein solubility was 2.2% in control sample, Furthermore, the using of chemical treatment showed that protein isolate was reduced gradually and
... Show MoreIn this report Silver doped Tin Sulfide (SnS) thin films with ratio of (0.03) were prepared using thermal evaporation with a vacuum of 4*10-6 mbar on glass with (400) nm thickness and the sample annealing with ( 573K ). The optical constants for the wavelengths in the range (300-900) nm and Hall effect for (SnS and SnS:3% Ag) films are investigated and calculated before and after annealing at 573 K. Transition metal doped SnS thin films the regular absorption 70% in the visible region, the doping level intensification the optical band gap values from 1.5- 2 eV. Silver doped tin sulfide (SnS) its direct optical band gap. Hall Effect results of (SnS and SnS:3% Ag) films show all films were (p-type) electrical conductivity with resistivity of
... Show MoreDesign system often generated relationship within the frame work of their concept of interior design a system or more can be created between design relationships within this concept in the structure of its internal space product. Through the division of all to it parts to reveal the hidden places and stages of composition and their relationship and interdependence between them. And then re- composition of all its parts, doth in the deign process at the initial stages or in the processes of treatments that are necessary after the completion of design and circulation. To be able to use other events close to the first events designed for them. In terms of idea logical in fluency and its social, economic, cultural and political dimension. As
... Show MoreGlass Fiber Reinforced Polymer (GFRP) beams have gained attention due to their promising mechanical properties and potential for structural applications. Combining GFRP core and encasing materials creates a composite beam with superior mechanical properties. This paper describes the testing encased GFRP beams as composite Reinforced Concrete (RC) beams under low-velocity impact load. Theoretical analysis was used with practical results to simulate the tested beams' behavior and predict the generated energies during the impact loading. The impact response was investigated using repeated drops of 42.5 kg falling mass from various heights. An analysis was performed using accelerometer readings to calculate the generalized inertial load. The in
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To promote sustainable steel-concrete composite structures, it is essential to develop special shear connectors that facilitate accelerated construction and deconstruction. A lockbolt demountable shear connector (LBDSC) was recently proposed. While the LBDSC has been evaluated using horizontal and vertical (standard) push-out tests, it is essential to further assess the disassembly mechanism and the positive flexural performance of prefabricated demountable composite beams (PDCBs) under both serviceability and ultimate limit states. Two full-scale test specimens of PDCBs with LBDSC were designed with partial shear connections and assessed using a three or four-point load beam setup under both cyclic and static monotonic loading conditions.
... Show MoreIntroduction The pathophysiology of appendicitis likely stems from obstruction of the appendiceal orifice leading to an increase in intraluminal and intramural pressure, resulting in small vessel occlusion and lymphatic stasis. Organ supplied by an end artery, such as the appendix, are more prone to the deleterious effects of arterial occlusion. The continuous cigarette smoking might be associated with a greater risk for developing atherosclerosis.
Objectives The aim is to evaluate the effect of cigarette smoking on the incidence of complications of acute appendicitis.
Methods Patients suffered from symptoms and signs suggesting a
One of the challenging issues encountered during drilling operations is the lost circulation. Numerous issues might arise because of losses, such as wasting of time and higher drilling cost. Several types of lost circulation materials have been developed and are being used to limit mud losses and avoid associated issues. Each solution has benefits and drawbacks.
In this study, a core flooding test was performed to study the effectiveness of polyacrylamide (PAM) granular gel on the reduction of the circulation lost. One common type of fracture characteristic is fractures with tips, commonly known as partially open fracture (POF). However, PAM gel therapy in POFs received little attention in prior research. Models of partly open fra
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