• Title/Summary/Keyword: Diaphragm system

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Computer Analysis of Non-vaulted Nef Unique System

  • Hong, Seong-Woo
    • Architectural research
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    • v.2 no.1
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    • pp.1-6
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    • 2000
  • Ever since Viollet-le-Due began to examine Gothic structural elements using his method of geometrical analysis in the nineteenth century, art and architectural historians and a few engineers have periodically attempted to ascertain the structural advantages of the various characteristic features of Gothic architecture. In none of these studies, however, has the way forces work within the lightweight and spacious masonry Gothic buildings been precisely interpreted. The approach taken by art and architectural historians has therefore tended to be primarily descriptive and to be based on intuitive assumptions. This study intend to analyze the Gothic non-vaulted nef unique(aisleless) structures of Lower Languedoc which has never been scientifically tested, and to provide as comprehensive an explanation as possible of the way in which these non-vaulted buildings work. In order to achieve this goal, this paper Is to examine, by means of finite element analysis. the links between the width of non-vaulted aisleless structures, the configuration of the arches, diaphragm arch, and the buttress. Finite element analysis with a computer provides a more accurate analysis than the methods of analysis that have been heretofore applied to Gothic structures, as well as permits us to visualize the global stress behavior of the structure. Combined with traditional methods of studying historical buildings, therefore, finite element analysis inevitably give us a broader understanding of the processes involved in the design and construction of medieval buildings.

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Analysis of a Building Structure with Added Viscoelastic Dampers

  • Lee, Dong-Guen;Hong, Sung-Il;Kim, Jin-Koo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.2 no.3
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    • pp.27-35
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    • 1998
  • Steel structures with added viscoelastic dampers are analysed to investigat their behavior under earthquake excitation. The direct integration method, which produces exact solution for the non-proportional or non-classical damping system, is used throughout the analysis. The results from modal strain energy method are also provided for comparison. Then a new analytical a, pp.oach, based on the rigid floor diaphragm assumption and matrix condensation technique, is introduced, and the results are compared with those obtained from direct integration method and modal strain energy method. The well known phenomenon, that the effectiveness of the viscoelastic dampers depends greatly on the location of the dampers, is once again confirmed in the analysis. It is also found that the modal strain energy method generaly underestimates the responses obtained from the direct integration method, especially when the dampers are placed in only a part of the building. The proposed method turns out to be very efficient with considerable saving in computation this and reasonably accurate considering the reduced degrees of freedom.

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Fabrication and Characteristics of pressure sensors for high pressure (고압용 압력센서의 제작과 그 특성)

  • Choi, Sung-Kyu;Seo, Jeong-Hwan;Chung, Gwiy-Sang
    • Proceedings of the KIEE Conference
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    • 2001.07c
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    • pp.1375-1377
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    • 2001
  • This paper describes the fabrication and characteristics of CrN thin-film type pessure sensors, in which the sensing elements were deposited on SUS. 630 diaphragm by DC reactive magnetron sputtering in an argon-nitride atmosphere(Ar-(10%) $N_2$). The optimized condition of CrN thin-film sensing elements was thickness range of 3500$\AA$ and annealing condition($300^{\circ}C$, 3 hr) in Ar-10 %$N_2$ deposition atmosphere. Under optimum conditions, the CrN thin-films for strain gauges is obtained a high resistivity, $\rho$=1147.65 ${\mu}{\Omega}$cm, a low temperature coefficient of resistance, TCR=-186 ppm/$^{\circ}C$ and a high temporal stability with a good longitudinal, 11.17. The output sensitivity of fabricated CrN thin-film type pressure sensors is 2.36 mV/V, 4$\sim$20 mA and the maximum non-linearity is 0.4 %FS and hysteresis is less than 0.2 %FS..

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The Frequency Effect in the Somatosensory Cortex Response to Vibrotactile Stimulator in fMRI (기능적 자기공명영상에서 진동자의 자극 주파수가 감각피질의 반응에 미치는 영향)

  • Lee Hyunsook
    • Progress in Medical Physics
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    • v.15 no.3
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    • pp.128-133
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    • 2004
  • The fMRI response of the somatosensory cortex was investigated with vibrotactile stimulation. Three different frequencies of 8, 15, or 25 Hz were applied in order to mainly focus on the hemodynamic response of Meissner corpuscles sensitive to frequencies of 5-40 Hz. A closed-system, pneumatically-driven, rubber diaphragm was fabricated that overcame many of the limitations of existing vibrotactile devices and produced robust sensory cortex activation in an fMRI experiment. Increasing frequency vs. activation area was analyzed in terms of signal percent change and number of pixels. Our preliminary results indicated that the distribution of the signal percentage change widened and more activated pixels were obtained with higher frequencies.

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Development of having double-chamber in micro-bubble pump (두 개의 챔버를 갖는 마이크로 버블펌프의 개발)

  • 최종필;박대섭;반준호;김병희;장인배;김헌영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1186-1190
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    • 2003
  • In this paper, a valveless bubble-actuated fluid micropump was has been developed and its performance was tested. The valveless micropump consists of the lower plate, the middle plate, the upper plate and a resistive heater. The lower plate includes the nozzle-diffuser elements and the double-chamber. Nozzle-diffuser elements and a double-chamber are fabricated on the silicon wafer by the DRIE(Deep Reactive Ion Etching) process. The lower plate also has inlet/outlet channels for fluid flow. The middle plate is made of glass and plays the role of the diaphragm. The chamber in the upper plate is filled with deionized water, and which contacts with the resistive heater. The resistive heater is patterned on a silicon substrate by Ti/Pt sputtering. Three plates and the resister heater are laminated by the aligner and bonded in the anodic bonder. Since the bubble is evaporated and condensed periodically in the chamber, the fluid flows from inlet to outlet with respect to the diffusion effect. In order to avoid backflow, the double chamber system is introduced. Analytical and experimental results show the validity of the developed double-chamber micropump.

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Efficacy and General Pharmacology of Recombinant Human Erythropoietin(DA-3285) (Recombinant Human Erythropoietin(DA-3285)의 효력 및 일반약리작용)

  • 김동환;안병옥;손문호;신명수;이성희;김원배;양중익
    • Biomolecules & Therapeutics
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    • v.4 no.1
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    • pp.68-77
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    • 1996
  • Efficacy and general pharmacology of recombinant human erythropoietin (rHu-EPO), were investigated. Efficacy studies were conducted in normal, cisplatin- and acute hemorrhage-induced anemic rats. Normal and anemic animals were treated intravenously with rHu-EPO for 5 days and the changes in the numbers of red blood cells (RBC), hemoglobin (Hb), hematocrit (Hct) and reticulocytes (Ret) were examined. In normal rats, rHu-EPO significantly increased RBC, Hb, Hct and Ret at doses of 50∼ 1250 IU/kg/day. Cisplatin-induced anemic rats showed significant increase of RBC, Hb, Hct and Ret in a dose-dependent manner after administration of rHu-EPO (50∼200 lU/kg/day). And in acute hemorrhage-induced anemic rats, rHu-EPO(4∼100 Iu/kg/day) accelerated recovery of anemia with significant increase in Ret. These changes disappeared gradually after cessation of the treatment. The general pharmacological effects of rHu-EPO were investigated in mice, rats, guinea-pigs, rabbits and cats. rHu-EPO had no influences on central nervous, cardiovascular, gastrointestinal and blood coagulation system. It also had no influence on the contraction of phrenic nerve-diaphragm preparation. rHu-EPO produced significant increase of urine volume at a dose of 7000 IU/kg. These results suggest that rHu-EPO might be useful for the therapy of anemia without serious side effect.

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Multiple criteria decision making method for selecting of sealing element for earth dams considering long and short terms goals

  • Rashidi, Babak;Shirangi, Ehsan;Baymaninezhad, Matin
    • Wind and Structures
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    • v.26 no.2
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    • pp.69-74
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    • 2018
  • Nowadays, using math logic in great civil projects is considered by the clients to achieve the goals of project including quality optimization, costs, avoiding individual, emotional and political decision making, long-term and short-term goals and they are the main requirements of each project and should be considered by the decision makers to avoid the illogical decision making applied on the majority of civil projects and this imposes great financial and spiritual costs on our country. The present study attempts to present one of the civil projects (Ghasre Shirin storage dam) whose client was not ministry of energy for the first time and the short-term and long-term goals of the private sector were applied based on the triangle of quality, cost and time. Also, the math logic and model (multi-criteria decision making method and decision making matrix) is used in one of the most important sections of project, sealing element, policies and new materials (Geosynthetics) are considered and this leads to suitable decision making in this regard. It is worth to mention that this method is used for other sections of a dam including body, water diversion system, diaphragm and other sectors or in other civil projects of building, road construction, etc.

The characteristics of suction pressure by throttle opening of the carburetor dummy at steady state (정상상태에서 카뷰레터 더미모델의 스로틀 개도에 따른 압력특성)

  • Cho, Hyoung-Mun;Kim, Byeong-Guk;Choi, Young-Ha;Yoon, Suck-Ju;Han, Jong-Kyu
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.711-714
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    • 2008
  • The objective of this paper is to know the characteristics of pressure through a simplified typical carburetor used in small engines at the different throttle opening conditions. The carburetor is the device responsible for creating the right air-fuel mixture according to the different engine operating conditions. It is activated by the static or the dynamic pressure. The carburetor dummy is geometrically similar of LPG brush-cutter engine's diaphragm carburetor and is made of acrylic. Suction system gives body to crankcase vacuum using the vacuum pump and throttle opening conditions are controled by transfer device. Carburetor venturi throat and fuel charging tube diameter is each 20mm, 4.1mm. The result of the work presents an unprecedented phenomenon of suction pressure variation inside the carburetor venturi. It is predicted that these unprecedented pressure variation be caused by minor losses; sudden contraction or expansion, open or partially closed and so on.

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Mechanical performance of a new I-section weak-axis column bending connection

  • Lu, Linfeng;Xu, Yinglu;Lim, James B.P.
    • Steel and Composite Structures
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    • v.26 no.1
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    • pp.31-44
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    • 2018
  • This paper reports a novel steel beam-to-column connection suitable for use in the weak axis of I-section column. Monotonic and cyclic loading experimental investigations and numerical analysis of the proposed weak-axis connection were conducted, and the calculation procedure of the beam-column relative rotation angle and plastic rotation angle was developed and described in details. A comparative analysis of mechanical property and steel consumption were employed for the proposed I-section column weak-axis connection and box-section column bending connection. The result showed that no signs of fracturing were observed and the plastic hinge formed reliably in the beam section away from the skin plate under the beam end monotonic loading, and the plastic hinge formed much closer to the skin plate under the beam end cyclic loading. The fracture of welds between diaphragm and skin plate would cause an unstable hysteretic response under the column top horizontal cyclic loading. The proposed weak-axis connection system could not only simplify the design calculation progress when I-section column is adopted in frame structural design but also effectively satisfy the requirements of 'strong joint and weak member', as well as lower steel consumption.

The Effect of Kinesio Taping as to Asthmatic (천식환자에 대한 키네시오 테이핑의 효과)

  • Lee, Duck-Soon;Kim, Chan-Kyu;Cho, Byeong-Mo
    • Journal of Korean Physical Therapy Science
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    • v.9 no.1
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    • pp.9-15
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    • 2002
  • The asthma is a clinical syndrome having three symptoms; dyspnea, wheezing and coughing, due to the narrowing of trachea in pulmonary system. Specially the asthma is common in children. The study was designed to identify the effect of Kinesio Taping Treatment as to asthmatic children. The Kinesio Taping Treatment was used on the Pectoralis major and Posterior diaphragm of twenty five asthmatic children(19 male, 6 female) for the period from September 1, 2001 to September 20, 2001. Peak expiratory flow rate(PEFR) for the condition of pulmonary function was measured using the Pocket Peak and wheeling and coughing symptom were measured using questionnaire. The results of this study are as follows: 1. There were statistically significant differences between before using the taping and after the kinesio taping increase of the PEFR(p<0.001). 2 There were statistically significant differences between before using the kinesio taping and after the kinesio taping improvement of the wheezing sign(p<0.001). 3. There were statistically significant differences between before using the kinesio taping and after the kinesio taping improvement of the coughing symptom(p<0.001).

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