• Proceedings of the Korea Concrete Institute Conference
• /
• 2004.05a
• /
• pp.462-465
• /
• 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.

• The Bulletin of The Korean Astronomical Society
• /
• v.34 no.2
• /
• pp.66.1-66.1
• /
• 2009

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05a
• /
• pp.647-652
• /
• 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.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05a
• /
• pp.635-640
• /
• 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.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.11a
• /
• pp.225-228
• /
• 2010

In this paper, the present status of research, development, and required technologies for the thermal barrier type dual-pulse rocket motor of the advanced countries was analysed. The result of the conceptual design of the forward or backward ignition systems was also demonstrated.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2019.01a
• /
• pp.349-350
• /
• 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.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2011.04a
• /
• pp.1394-1397
• /
• 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.

• The Journal of Internal Korean Medicine
• /
• v.30 no.1
• /
• pp.85-93
• /
• 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.

• Natural Product Sciences
• /
• v.19 no.3
• /
• pp.251-257
• /
• 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.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.6 no.2
• /
• pp.79-86
• /
• 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.