299 research outputs found

    TRAINING EFFECT OF RUNNING OVER FLAT MARKERS TO INCREASE STRIDE LENGTH - A CASE STUDY -

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    The purpose of this study was to verify the effect of running over flat markers (FMR) using longer than usual stride length intervals. One male collegiate sprinter participated in this study as the subject. The subject initially ran 100m normally, and we calculated the stride length during this run. He was FMR training for 4 weeks with a mark interval set up at 105% of usual stride length. The sprint motion of the three runs were compared by two-dimensional motion analysis. The result of the present study showed FMR changed leg motion just before the contact phase. The subject, whose leg motion showed hip angular velocity increased just before the contact phase. The result of the present study show FMR may be a good tool for sprinting improvement to change leg motion

    COMPARISON OF SOLUTION ALGORITHM FOR FLOW AROUND A SQUARE CYLINDER

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    ABSTRACT Numerical accuracy, numerical stability and calculation time are all important factors in the computational fluid dynamics. In this study, we compare two solution algorithms, the Simplified Marker and Cell (SMAC) method in the MAC-type methods and the Semi-Implicit Method for Pressure-Linked Equation (SIMPLE) algorithm in the SIMPLE-type algorithms, with respect to flow around a square cylinder in constant density and unsteady-state calculations using a staggered grid to investigate the numerical accuracy, the numerical stability and the computational time. For the flow around a square cylinder, the SMAC and SIMPLE solutions are in excellent agreement at the Strouhal number, drag and lift coefficients. However, SMAC is more unstable than SIMLE with a large Courant number. The computational time of the SMAC is shorter than that of the SIMPLE with a small Courant number

    Effect of operating conditions on fluid flow over a high speed rotary bell-cup atomizer

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    Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.Using the volume of fluid (VOF) method, we analyze two-dimensional fluid flow over high-speed rotary bell-cup atomizers. The fluid behavior is analyzed and the liquid film thickness is quantitatively evaluated. The atomizer is flat in shape and has a paint supply hole. The bell rotational speed obtained is 15,000, 25,000, and 35,000 rpm; and the liquid flow rate obtained is 150, 300, 450, and 600 mL/min. The liquid used in this experiment is assumed to be water and the gas is assumed to be air. The results show that the liquid flows through the bell-cup surface toward the edge and forms a liquid film. At the measuring point, the film is initially thick but it then decreases to a practically constant value. The increase in the bell rotational speed causes the film thickness to decrease. Furthermore, the increase in the rotational speed causes the film thickness to become constant, whereas the increase in the liquid flow rate causes the film thickness to increase. These results show that the rotational speed and flow rate strongly affect the thickness of the filmdc201

    Space Demonstration of Two-Layer Pop-Up Origami Deployable Membrane Reflectarray Antenna by 3U CubeSat OrigamiSat-2

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    3U CubeSat OrigamiSat-2 demonstrates a 50-cm × 50-cm two-layer pop-up Origami deployable membrane reflectarray antenna in space. The membrane has small stowage volume and high gain even though it has low flatness because of a large enough antenna area to cover its un-flatness. C-band transmitter is equipped in the CubeSat and offers 20-Mbps amateur satellite communication. In 3U size, a 1-m length deployable gravity gradient mast and magnetic torquer are equipped to stabilize and control its attitude. A camera is attached to the satellite to measure the shape of the membrane antenna. OrigamiSat-2 was selected as the Innovative Satellite Technology Demonstration-4 by Japan Aerospace Exploration Agency (JAXA) and is going to be launched in 2024 by Epsilon Launch Vehicle

    One-Step Detection of the 2009 Pandemic Influenza A(H1N1) Virus by the RT-SmartAmp Assay and Its Clinical Validation

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    <div><h3>Background</h3><p>In 2009, a pandemic (pdm) influenza A(H1N1) virus infection quickly circulated globally resulting in about 18,000 deaths around the world. In Japan, infected patients accounted for 16% of the total population. The possibility of human-to-human transmission of highly pathogenic novel influenza viruses is becoming a fear for human health and society.</p> <h3>Methodology</h3><p>To address the clinical need for rapid diagnosis, we have developed a new method, the “RT-SmartAmp assay”, to rapidly detect the 2009 pandemic influenza A(H1N1) virus from patient swab samples. The RT-SmartAmp assay comprises both reverse transcriptase (RT) and isothermal DNA amplification reactions in one step, where RNA extraction and PCR reaction are not required. We used an exciton-controlled hybridization-sensitive fluorescent primer to specifically detect the HA segment of the 2009 pdm influenza A(H1N1) virus within 40 minutes without cross-reacting with the seasonal A(H1N1), A(H3N2), or B-type (Victoria) viruses.</p> <h3>Results and Conclusions</h3><p>We evaluated the RT-SmartAmp method in clinical research carried out in Japan during a pandemic period of October 2009 to January 2010. A total of 255 swab samples were collected from outpatients with influenza-like illness at three hospitals and eleven clinics located in the Tokyo and Chiba areas in Japan. The 2009 pdm influenza A(H1N1) virus was detected by the RT-SmartAmp assay, and the detection results were subsequently compared with data of current influenza diagnostic tests (lateral flow immuno-chromatographic tests) and viral genome sequence analysis. In conclusion, by the RT-SmartAmp assay we could detect the 2009 pdm influenza A(H1N1) virus in patients' swab samples even in early stages after the initial onset of influenza symptoms. Thus, the RT-SmartAmp assay is considered to provide a simple and practical tool to rapidly detect the 2009 pdm influenza A(H1N1) virus.</p> </div
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