• 제목/요약/키워드: resistance capacity

검색결과 1,661건 처리시간 0.03초

Inhaled iloprost for the treatment of patient with Fontan circulation

  • Kim, Yong Hyun;Chae, Moon Hee;Choi, Deok Young
    • Clinical and Experimental Pediatrics
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    • 제57권10호
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    • pp.461-463
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    • 2014
  • Decreased exercise capacity after Fontan surgery is relatively common and the failure of the Fontan state gradually increases with age. However, there is no further treatment for patients with Fontan circulation. Pulmonary vasodilation therapy is an effective method to solve this problem because pulmonary vascular resistance is a major factor of the Fontan problem. Inhaled iloprost is a chemically stable prostacyclin analogue and a potent pulmonary vasodilator. We experienced two cases of Fontan patients treated with inhaled iloprost for 12 weeks. The first patient was an 18-year-old female with pulmonary atresia with an intact ventricular septum, and the second patient was a 22-year-old male with a double outlet right ventricle. Fifteen years have passed since both patients received Fontan surgery. While the pulmonary pressure was not decreased significantly, improved exercise capacity and cardiac output were observed without any major side effects in both patients. The iloprost inhalation therapy was well tolerated and effective for the symptomatic treatment of Fontan patients.

권상용량 증가에 따른 컨테이너 크레인의 내풍특성 비교 (A Comparison of the Wind Resistance Characteristic of a Container Crane According to the Increase to the Lifting Capacity)

  • 이성욱;김형훈;한동섭;한근조;김태형
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.204-209
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    • 2007
  • This study was carried out to analyze the effect of wind load on the structural stability of a container crane according to the increase of the lifting capacity using wind tunnel test and provided a container crane designer with data which can be used in a wind resistance design of a container crane assuming that a wind load at 75m/s wind velocity is applied on a container crane. Data acquisition conditions for this experiment were established in accordance with the similarity. The scale of a container crane dimension, wind velocity and time were chosen as 1/200, 1/13.3 and 1/15. And this experiment was implemented in an Eiffel type atmospheric boundary-layer wind tunnel with $11.52m^{2}$ cross-section area. Each directional drag and overturning moment coefficients were investigated.

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슬래브-기둥 접합부의 내진성능을 위한 래티스 전단보강 (Lattice Shear Reinforcement for Earthquake-Resistance of Slab-Column Connection.)

  • 김유니;박홍근
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.26-29
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    • 2006
  • A flat plate-column connection is susceptible to brittle punching shear failure, which may result in the necessity of shear reinforcement. In present study, experimental tests were performed to study the capacity of slab-column connections strengthened with lattice, stud rail, shear band and stirrup under gravity and cyclic lateral load. Among them, the capacity of the specimens with lattice are superior to the others due to the truss action of the lattice bars and dowel action of the longitudinal bars as well as the shear resistance of the web re-bar. On the other hand, the strengths of the specimens with stud rail, shear band and stirrup are lower than the estimated strength by the ACI, therefore design formulas of the ACI are needed to revise.

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소용량 EHD 발전에 관한 실험적 연구 (An Experimental Study on the Small Capacity EHD Power Generation)

  • 전춘생;이재복;임응춘
    • 태양에너지
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    • 제9권2호
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    • pp.58-68
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    • 1989
  • This paper describes an experimental study that was performed to determine the limiting factors on the power output in the closed cycle Electro-Hydro-Dynamic generator of small capacity. A corona discharge for producing unipolar charged particles used as the charging method. The experiment demonstrated that the corona method of charging was an efficient and effective means of producing unipolar charged particles. Four factors having an effect on the power output characteristics of EHD generator are discussed and examined experimentally, using methyl alcohol and kerosene as working fluides; a. The conversion length between attractor and collector. b. The corona current of Emitter. c. The flow velocity of working fluids. d. Load resistance. This results are as follows; 1) There in a critical value in conversion length for its maximum power output. 2) Power output increases almost linearly with corona current and flow velocity. 3) There is the critical value of load resistance producing a maximum power output. 4) Kerosene is known better working fluid than Methyl alcohol in this EHD generator.

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철근콘크리트 기둥과 철골 보의 접합부 형식 발전 및 용접성능에 관한 시험적 연구 (A Study on the Improvement and Test on Welding Performance of R/C Column-Steel Girder Connection)

  • 최광호;이세웅;김재순;김상식
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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    • pp.569-574
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    • 1997
  • This research has improved composite joint system of R/C column and steel beam developed at previous study. In this system, the shear force occurred at beam is transmitted by bearing resistance of stiffness and moment is resisted by tension capacity of coupling members. As the preliminary step of stress transfer tests of this system, welding performance test of coupling member such as round bar or square bar which has a role of moment transfer has been carried out. From the test, this element has a good welding performance and enough resistance capacity compared to design force.

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고강도 콘크리트 휨부재의 정착 및 겹침이음길이에 관한 실험적 연구 (Experimental Research on Development and Splices Length in High-Strength Concrete Flexural Members)

  • 이기열;김우;정기오
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.865-871
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    • 2003
  • This paper presents the test results of 24 beam-end specimens to investigate the effect of concrete strength and cover thickness on the development resistance capacity in tensile lap splice length regions. The results showed that as higher strength concrete was employed, nor only development resistance capacity was influenced by cover thickness, but also more sufficient safety factor reserved shorter than the lap splice length provision in current design code. From experimental research results, high-strength concrete development length was not inverse ratio of ($\sqrt{f_{ck}}$) but directly inverse of $f_{ck}$, and it is also said that there is a certain limit length of the embedded steel over which the assumption of uniform bond stress distribution is valid specially for high-strength concrete not having a same embed length such as normal-strength concrete in current design criteria hypothesis.

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다층 고온초전도 송전케이블의 길이에 따른 층별 전류분류 및 교류손실 계산 (Current Sharing and AC Loss of a Multi-Layer HTS Power Transmission Cable with Variable Cable Length)

  • 이지광;차귀수
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제50권1호
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    • pp.10-14
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    • 2001
  • The superconducting transmission cable is one of interesting part in power application using high temperature superconducting wire. One important parameter in HTS cable design is transport current sharing because it is related with current transmission capacity and loss. In this paper, we calculate self inductances of each layer and mutual inductances between two layers from magnetic field energy, and current sharing of each layer for 4-layer cable using the electric circuit model which contain inductance and resistance (by joint and AC loss). Also, transport current losses which are calculated by monoblock model and Norris equation are compared. As a results, outer layer has always larger transport current than inner layer, and current capacity of each layer is largely influenced by resistance per unit cable length. As a conclusion, for high current uniformity and low AC loss, we have to decrease inductances themselves or those differences.

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복사열전달을 고려한 고층아파트 연속난방 열공급제어 시뮬레이션 (Simulation of Heat Supply Control of Continuous Heating System of Multistoried Apartment in Consideration of Radiation Heat Transfer)

  • 최영돈;홍진관;윤종호;이남호
    • 설비공학논문집
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    • 제6권2호
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    • pp.78-92
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    • 1994
  • Thermal performance of pipe network of continuous heating system controlled by thermostat and flow control valve was simulated in consideration of radiation heat transfer and solved by linear analysis method. Thermal performance of real apartment building with radiant floor heating system was simulated by equivalence heat resistance-capacity method. This method enables to simulate the unsteady variation of temperature or each element of building. Heat transfer characteristics of each element were also investigated.

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기존선 급곡선부의 장대화 방안에 대한 연구 (A study on constructing CWR for railroad under operation)

  • 양신추;노혁천;김은;이종득
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2001년도 춘계학술대회 논문집
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    • pp.303-310
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    • 2001
  • The railroad under operation has very sharp curves and the state of ballast is somewhat deteriorated due to the traffic loads, which put some constraints in converting the conventional rails into CWR. In making CWR, the determination whether the ballast has sufficient capacity for resisting buckling must be made, quantitatively and qualitatively, and schemes to guarantee the required lateral resistance of ballast should be proposed. In this study, using the in-situ investigated data, the probability of buckling of CWR is given for several installation temperatures for CWR. The effect of tamping, DTS, and sleeper spacing are taken into account. The buckling probability is given as a function of curvature and installation temperature of CWR and works used to increase the ballast resistance capacity after tamping, i.e., DTS and reduction of sleeper sparing.

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고분자 결합제를 이용한 수소저장합금 분말 성형체의 특성 (Characteristics of Hydrogen Storage Alloy powder Compacts Using Polymer Binders)

  • 김찬중;김대룡
    • 한국수소및신에너지학회논문집
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    • 제10권2호
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    • pp.81-89
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    • 1999
  • Various characteristics - mechanical propertis, thermal cyclic hydriding characteristics and resistance to degradation by $H_2O$, CO in hydrogen - of hydrogen storage alloy powder compacts using PTFE and silicon sealant as a polymer binder were studied. Diametral tensile strength of 10wt% PTFE and 5wt% silicon sealant added compacts showed relatively high value of $4kg/cm^2$ and $10kg/cm^2$, respectively. Compacts show a good resistance to degradation by $H_2O$ in hydrogen. But hydrogen absorption rate and capacity of compacts were decreased by CO in hydrogen with the number of cycles. Cu coated and PTFE bonded compacts showed very small decrease of capacity and a good strength even after 1000 cycles of thermal hydriding and dehydriding.

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