• 제목/요약/키워드: Won Bang

검색결과 1,169건 처리시간 0.028초

A Study on Mesh Sensitivity of 3-D Homoginized Crack Model for Concrete Fracture Analysis

  • 남진원;송하원;변근주;방춘석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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    • pp.462-465
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    • 2004
  • Since quasi-brittle materials like concrete show strain localization behavior accompanied by strain softening, a numerical drawback such as mesh sensitivity is appeared in the finite element analysis. In this paper, the so-called homogenized crack model which was introduced for three dimensional finite element analysis of fracture in concrete is studied for the mesh size dependence problem in fracture analysis. A homogenized crack element having a velocity discontinuity. is averaged to remove the mesh sensitivity in finite element analysis of concrete fracture. Numerical examples show that softening behavior of concrete fracture is successfully predicted without mesh sensitivity using the homogenized crack model.

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Containment Closure Time Following Loss of Cooling Under Shutdown Conditions of YGN Units 3&4

  • Seul, Kwang-Won;Bang, Toung-Seok;Kim, Se-Won;Kim, Hho-Jung
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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    • pp.647-652
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    • 1998
  • The YGN Units 3&4 plant conditions during shutdown operation were reviewed to identified the possible even scenarios following the loss of shutdown cooling. The Thermal hydraulic analyses were performed for the five cases of RCS configurations under the worst event scenario, unavailable secondary cooling and no RCS inventory makeup, using the RELAP5/MOD3.2 code to investigate the plant behavior, From the analyses results, times to boil, times to core uncovery and times to core heat up were estimated to determined the containment closure time to prevent the uncontrolled released of fission products to atmosphere, These data provide useful information to the abnormal procedure to cope with event.

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Thermal Fluid Mixing Behavior during Medium Break LOCA in Evaluation of Pressurized Thermal Shock

  • Jung, Jae-Won;Bang, Young-Seok;Seul, Kwang-Won;Kim, Hho-Jung
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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    • pp.635-640
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    • 1998
  • Thermal fluid mixing behavior during a postulated medium-size hot leg break loss of coolant accident is analyzed for the international comparative assessment study on pressurized thermal shock (PTS-ICAS) proposed by OECD-NEA. The applicability of RELAP5 code to analyze thermal fluid mixing behavior is evaluated through a simple modeling relevant to the problem constraints. Based on the calculation result, the onset of Thermal stratification is investigated using Theofanous's empirical correlation. Sensitivity calculations using a fine node model and crossflow model are also performed to evaluate the modeling capability on multi-dimensional characteristics related to thermal fluid mixing.

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격막형 펄스분리장치 기술동향 연구 (Study on the Technical Trend of a Pulse Separation Device with Thermal Barrier Type)

  • 김원훈;이방업;구송회;이원복
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2010년도 제35회 추계학술대회논문집
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    • pp.225-228
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    • 2010
  • 본 논문에서는 서방에서의 격막형 펄스분리장치를 적용한 다중펄스 로켓모타 기술개발 현황과 소요 기술을 분석하였으며, 전방 및 후방 점화 시스템 방식의 이중펄스 로켓모타에 대한 개념설계 결과를 제시하고 있다.

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유한 상태 기계를 이용한 몬스터 AI 구현에 관한 연구 (A study on The Implementation of Monster AI using Finite-State Machine)

  • 조재원;방정원
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2019년도 제59차 동계학술대회논문집 27권1호
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    • pp.349-350
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    • 2019
  • 게임에서 장르를 불문하고 모든 몬스터와 NPC는 AI를 가지고 있다. 따라서 적 몬스터 캐릭터와 전투를 즐기는 액션 게임의 경우 그만큼 인공지능이 게임 안에서 차지하는 비율이 높다고 할 수 있을 것이다. 본 논문에서는 FSM, HFSM, BT와 같은 AI 기법을 비교하여 분석하였다. 각 기법에는 주의해야 할 점이 명확하게 존재하기 때문에 구체적으로 어떠한 문제점들이 존재하는지에 대한 결과를 얻는데 연구 목적이 있다. 따라서 몬스터 AI를 구현할 때 각 인공지능 기법의 장단점을 고려하여 설계하여 유지 보수를 줄이는 방법을 연구해야 한다는 것을 확인할 수 있었다.

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ALE 구조 기반의 RFID 미들웨어를 이용한 이기종 리더 처리시스템 구현 (Based on the ALE-Construct an Implementation Various Reader devices Using RFID Middleware)

  • 김상헌;방상원;김병기
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2011년도 춘계학술발표대회
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    • pp.1394-1397
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    • 2011
  • RFID 기술을 이용한 다른 분야에서 사용하고 있는 응용과의 통합 및 데이터 수집, 제어, 관리, 등을 지원하는 RFID 미들웨어의 중요성이 확산 되고 있다. RFID 기술이 확산됨에 따라 EPCGlobal 에서는 RFID 하드웨어와 응용 사이에 존재하는 ALE(Application Level Events) 표준 스펙을 검증 및 절차를 통일하여 정의하였다. 그러나 대규모의 분산된 실제 현장을 대상으로 시스템 방식을 생각해보면 ALE방식이 다양한 RFID 리더들을 처리하는데 있어서 유용하지 않다. 따라서 본 논문에서는 ALE 표준 규약형식은 지키며 다양한 RFID 리더 처리를 보증 하기위하여 기능들을 재정의 한다. 재정의 된 기능들을 기반으로 다양한 RFID 리더 들을 처리하기 위하여 인터페이스를 정의한다. 이를 통하여 RFID 미들웨어 성능을 높이는 시스템을 제안하고자 한다.

식적(食積) 및 음허(陰虛)로 인한 해수 환자의 임상적 특성 분석 (An Analysis of Clinical Characteristics of Patients with Cough by Food-accumulation and Yin-Deficiency)

  • 이정욱;박상무;강백규;한덕진;나란희;방창호;장석오;손지우;이시형
    • 대한한방내과학회지
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    • 제30권1호
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    • pp.85-93
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    • 2009
  • Cough is a common clinical problem to which various etiologies are attributable. In Korean medicine there are differentiations in etiology such as food-accumulation and Yin-deficiency. This study was aimed to analyze the relations between the time of cough and Korean syndrome differentiations and to compare the symptoms of Korean syndrome differentiations (food-accumulation and Yin-deficiency). Sixty-two cough patients were analyzed and classified into one of two syndrome differentiations by etiology. We compared the time of coughing and symptomatic characteristics of two: such as symptom differences and change of severity after treatment. Patients with food-accumulation were more prevalent than patients with Yin-deficiency. Among symptoms, anorexia, dyspepsia, nausea and nasal discharge were more prevalent in food-accumulation while pruritus of throat was prevalent in Yin-deficiency. Coughing at night was prevalent in Yin-deficiency and coughing at rising hour was prevalent in food-accumulation.

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Evaluation of the Effects of Acorus gramineus and Acorus tatarinowii Extracts on a Rat Model of Arterial Thrombosis induced by Ferric Chloride

  • Bang, Jihye;Lee, Ki-Mo;Lee, In Sun;Heo, Eun-Jung;Kang, Hyung Won;Jeon, Won Kyung
    • Natural Product Sciences
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    • 제19권3호
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    • pp.251-257
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    • 2013
  • We investigated the antithrombotic effect of Acorus gramineus Soland (A. gramineus) from Korea and Acorus tatarinowii Schott (A. tatarinowii) from China in a rat model of arterial thrombosis induced by ferric chloride ($FeCl_3$). Thirty minutes prior to a 35% $FeCl_3$ application, Sprague Dawley rats were intraperitoneally injected with saline, A. gramineus and A. tatarinowii (100 mg/kg), respectively. Occlusion time of rats injected with A. gramineus was delayed significantly compared to that of the vehicle and A. tatarinowii. Thrombus weight was meaningfully decreased in rats injected with A. gramineus compared to the vehicle. Additionally, A. gramineus inhibited collagen fiber damage in vessel compared to the vehicle, but A. tatarinowii did not show a significant effect. Our results show that A. gramineus and A. tatarinowii from the same genus have different antithrombotic effects, and especially A. gramineus has a better antithrombotic effect than A. tatarinowii.

Effects on Optical Characteristics of GaN Polarity Controlled by Substrate

  • Kang, Sang-Won;Shim, Hyun-Wook;Lee, Dong-Yul;Han, Sang-Heon;Kim, Dong-Joon;Kim, Je-Won;Oh, Bang-Won;Kryliouk, Olga;Anderson, Timothy J.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제6권2호
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    • pp.79-86
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    • 2006
  • N-polar, Ga-polar, and non-polar GaN was grown by MBE and MOVPE using various substrates and influence of polarity has been investigated. The GaN growth by MOVPE is along cplane (0001), c-plane (0001), and a-plane (11-20) direction on c-plane (0001), a-plane (11-20) and r-plane (1-102) sapphire substrate respectively. The polarity of the film has a strong influence on the morphology and the optical properties of PA-MBE grown As-doped GaN layers. Strong blue emission from As-doped GaN was observed only in the case of N-polarity (000-1) layers, which was attributed to the highest concentration of Ga dangling bonds for this polarity of a GaN surface.