• Title/Summary/Keyword: Lee Sam

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An experimental study on motions of a VLCO for wave power generation(1. Simple floating body) (파력발전용 가변수주진동장치의 운동에 대한 실험적 연구(1. 단일 부유체))

  • Lee, Seung-Chul;Goo, Ja-Sam
    • Journal of Power System Engineering
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    • v.17 no.2
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    • pp.103-107
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    • 2013
  • The structure of a variable liquid column oscillator(a VLCO) is analogous to that of the tuned liquid column damper used to suppress oscillatory motion in large structures like tall buildings and cargo ships. The VLCO is a system absorbing high kinetic energy of accelerated motions of multiple floating bodies in the effect of air springs occurred by installation of inner air chambers. Thus, VLCO can improve the efficiency of energy than wave energy converters of the activating object type made in Pelamis Company. In this research, the experiment was performed that a simple floating body was filled with internal fluid of same draft. The characteristics of motions were evaluated in each case of the opening or closing of the upper valves.

한우 사육 농가의 유기순환 체계

  • Park, Jun-Hyeok;Yun, Gi-Yong;Lee, Ju-Sam
    • Proceedings of the Korean Society of Organic Agriculture Conference
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    • 2008.12a
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    • pp.139-145
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    • 2008
  • 1) 밭 토양의 질소공급능력은 밭작물 양분요구량의 1.2배였고, 논토양에서는 1.02로, 평균 1.11이었다. 2) 밭 토양에서 Ca, K 함량은 CNCs보다 낮았고, TN, Mg 함량은 CNCs보다 높았다. 논토양에서는 Ca, Mg, K는 CNCs보다 낮아서 양분의 불균형을 이루고 있다. 3) 작물생산량 중의 조사료 생산비율은 68.1%였다. 4) 조농비는 41:59(조사료 자급비율 91.4%) 5) 토양으로의 가축분뇨 질소환원 가능량은 1,034kg(발생 질소량의 60%)로 추정되었다. 6) 토양으로부터 작물로의 질소공급량은 토양 질소량의 72.4%인 1,383.3kg N으로 추정되었고, 천연양분공급량은 298.6 kg N, 잔류양분 287.7 kg N으로 추정되었다. 7) 토양-작물-가축간의 물질수지는 거의 균형을 이루고 있다고 판단되지만, 토양진단을 통한 양분불균형의 개선이 필요하고, 벼 재배 후 월동 사료작물 재배면적의 확대로 조사료 자급 율을 높이므로, 조농비의 개선이 필요 8) 특히 논 토양의 유박비료 시용량을 가축분뇨로 전량 대체하는 것이 경지 내에서의 물질순환 유지에 필요하다고 판단된다.

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The Transmissibility of the Compact Disc Player due to Temperature (온도변화에 기인한 컴팩트디스크 플레이어의 전달률)

  • Lee, Tae-Keun;Kim, Byoung-Sam;Chi, Chang-Heon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.19 no.9
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    • pp.967-972
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    • 2009
  • To investigate the vibration characteristics of compact disc player(CDP) due to excited vibration and disturbances, it is necessary to consider the transmissibility of the CDP. The disturbances as well as the temperature in the vehicle are the one of the important factors when CDP is designed. In this study, the effect on the temperature of the oil damper, which is applied to anti-vibration system of the CDP, was investigated. When the temperature was changed from $-30^{\circ}C$ to $90^{\circ}C$ and the properties of the oil damper (hardness of rubber, viscosity of oil) were changed, the transmissibility was measured. When the damper rubber has the large hardness, the difference of the transmissibility and natural frequency due to temperature showed the remarkable change as compared with the those of damper viscosity.

Measurement of Branching Ratio for broad 27-keV Resonance of $^{19}F(n,g)^{20}F$ Reaction by using Time-of-flight Method with Anti-Compton NaI(Tl) Spectrometer

  • Lee, Sam-Yol
    • Journal of the Korean Society of Radiology
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    • v.2 no.1
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    • pp.31-34
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    • 2008
  • The neutron capture spectrum for the light nuclide was very useful to study the nuclear structure. In the present study, the capture gamma-ray from the 27-keV resonance of $^{19}F(n,g)^{20}F$ reaction were measured with an anti-Compton NaI(Tl) spectrometer and the 3-MV Pelletron accelerator of the Research Laboratory for Nuclear Reactors at the Tokyo institute of technology. A neutron Time-of-Flight method was adopted with a 1.5 ns pulsed neutron source by the $^7Li(p,n)^7Be$ reaction. In the present experiment, a Teflon(($CF_2$)n) sample was used The sample was disk with a diameter of 90mm. The thickness of sample was determined so that reasonable counting rates could be obtained and the correction was not so large for the self-shielding and multiple scattering of neutrons in the sample, and was 5mm. The primary gamma-ray transitions were compared with previous measurement of Kenny.

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Diagnostic System of Modeling Errors Generated from IGES CAD Data Exchange (IGES CAD 데이터의 교환에서 오류 진단 시스템)

  • Park, Sang-Ho;Park, Jong-Wook;Han, Soon-Heung;Choi, Young;Yang, Jung-Sam;Lee, Byung-Hoon
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.10
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    • pp.218-225
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    • 2003
  • A diagnostic system has been developed which reports modeling errors generated when exchanging CAD data using IGES (Initial Graphics Exchange Specification) format. The system determines whether the CAD data contains errors. It also helps to define the criteria for determining the integrity and interoperability of CAD data with downstream applications of another CAD/CAM/CAE/PDM systems. The methodology of our algorithms is to analyze IGES model data by identifying errors and anomalies with respect to the diagnosis of geometry and topology. The GUI (Graphic User Interface) of the developed system helps users to input values and to visualize diagnostic results at real time.

Surgical Treatment for Acute Caustic Injury of the Hypopharynx, Esophagus, and Stomach -Two Cases- (하인두 및 위의 손상을 동반한 급성 부식성 식도손상의 외과적 치료)

  • Kim, Hyeong-Gon;Lee, Sam-Yun;Choe, Jong-Beom
    • Journal of Chest Surgery
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    • v.28 no.10
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    • pp.935-938
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    • 1995
  • Two cases of severe caustic injury of the hypopharynx, esophagus, and stomach are presented. Restoration of digestive continuity was accomplished by retrosternal isoperistaltic interposition of the transverse and left colon on the post-injury 73rd and 66th day respectively. The upper oro-colon continuity was made by a cervical approach, a vertical incision at the posterior hypopharyngeal wall, and interrupted one-layer sutures using 3-0 Dacron suture materials. The distal continuity was made by colojejunostomy between the transposed colon and proximal jejunum. There was no event after the operation in both cases. The posterior vertical hypopharyngotomy and hypopharyngocolostomy at the early post-injury period may be the preferred procedure to obtain normal deglutition in patients with esophageal stricture associated with hypopharyngeal injury.

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On the evolution of the galaxy morphology in the hierarchical universe

  • Lee, Jae-Hyun;Yi, Suk-Young
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.39.2-39.2
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    • 2010
  • We have investigated the evolution of the galaxy morphology in the hierarchical universe taking advantage of Semi-Analytic Model (SAM). It is well known that the galaxy morphology is related to the dynamical and the chemical evolution. This implies that we need to understand overall physical processes in the galaxy to reproduce its morphology. Thus we implemented gradual hot gas stripping of satellite galaxies in a galaxy cluster and recycling of stellar mass losses into our model in order to describe star formation rate of galaxies accurately. To morphologically classify galaxies, the evolution of disc and bulge components is traced carefully. We compute our models based on the dark matter halo merger trees generated by N-body simulations as well as the Extended Press-Schechter (EPS) formalism. We present morphological differences caused by the use of different merger trees.

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Bioavailability of Commercially Available Norfloxncin Tablets (시판 노르플록사신 정계의 생체내 이용률)

  • Lee, Chong Ki;Cho, Sam Sang
    • Korean Journal of Clinical Pharmacy
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    • v.6 no.2
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    • pp.14-18
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    • 1996
  • This study was attempted to investigate the dissolution rate and the bioavailability after oral administration of commercially available norfloxacin tablets in rabbits. The dissolution test was conducted in artificial gastric juice using basket method with for norfloxacin preparations (A, B, C and D) which were chemically equivalent. The results were as follows ; The dissolution rate was increased in the order of four different brand A>D>B>C. Area under the plasma concentration curve and peak plasma concentration were increased in the order of brand A>D>B>C. Absorption rate constant and peak time were increased in the order of brand B>A>C>D, and there was a little difference in elimination rate constant and biological half-life. The correlation of the dissolution rate and relative bioavailability showed significant linear relationship. From the results of this experiment, the bioavailability of norfloxacin tablets in rabbits may be predicted from the results of dissolution rate studies.

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