• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.5
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• pp.67-73
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• 2012

Failure mechanisms for a solid propellant were discussed, and the stip-yield and the inherent flaw models were applied to them. Then, failure assessment diagram methods were investigated by means of modified two models. Fracture toughness tests using CCT(center-cracked tension) specimens made of a solid propellant were conducted to generate the failure assessment diagrams. The failure assessment diagram of the inherent flaw model was normalized in order to compare with that of the modified strip-yield model. From the comparison of two failure assessment diagrams, it was found that the failure assessment diagram of the modified inherent flaw model more conservatively assesses the failure than that of the modified strip-yield model.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.532-538
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• 2012

Failure mechanisms for a highly filled elastomer were discussed, and the stip-yield and the inherent flaw models were applied to them. Then, failure assessment diagram methods were investigated by means of modified two models. Fracture toughness tests using CCT(center-cracked tension) specimens made of a highly filled elastomer were conducted to generate the failure assessment diagrams. The failure assessment diagram of the inherent flaw model was normalized in order to compare with that of the modified strip-yield model. From the comparison of two failure assessment diagrams, it was found that the failure assessment diagram of the modified inherent flaw model more conservatively assesses the failure than that of the modified strip-yield model.

• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.258-269
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• 2021

The purpose of this study is to establish a system to evaluate the ecological soundness of the Geum river basin. The study target area is 14 sub-watersheds of the Geum river basin. For the selection of indicators to ensure transparency and consistency of the evaluation indicators, the ecological soundness indicators were secured by using the indicator adjustment method derived in consideration of the intrinsic weight change characteristics between indicators. The index with the greatest impact on the final composite index was identified as the index of the aquatic ecology among the water quantity, water quality, aquatic ecology, and habitat-riparian environment dimensions. As a result of analyzing the ecological health index of the river, the watershed upstream of the dam (based on the Daecheong -dam) was evaluated to be in relatively good condition until 2014 compared to the base year(2008), and the watershed downstream of the dam was evaluated to be in a poor condition. The annual trend of changes in the ecological soundness index on an annual basis is as follows. In the case of Yongdamdam, Yongdamdamdownstream, Bocheong-chun, Daechungdam, Daechungdamdownstream, and Nonsancheon, although there are differences by time period, the soundness index is in declining. On the other hand, Mujunamdaecheon, Yeongdongcheon, and Gapcheon were evaluated to have improved soundness, while Chogang, Daechungdamupstream, Mihocheon, Gongjugeumgang, and Geumgangestuary were evaluated to deteriorate again after soundness was improved.

• Journal of Korea Game Society
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• v.17 no.1
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• pp.89-98
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• 2017

This paper presents a novel ARAP (as-rigid-as-possible) approach to real-time simulation of physics-based deformation. To cope with one, two and three dimensional deformable bodies in an efficient, robust and uniform manner, we introduce a deformation graph of oriented particles and formulate the corresponding ARAP deformation energy. For stable time integration of the oriented particles, we develop an implicit integration scheme formulated in a variational form. Our method seeks the optimal positions and rotations of the oriented particles by iteratively applying an alternating local/global optimization scheme. The proposed method is easy to implement and computationally efficient to simulate complex deformable models in real time.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.227-236
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• 2003

The evaluation of the reliable strength and deformation characteristics of weathered granite masses is very important for the design of geotechnical structure under working stress conditions. Various types of laboratory test such as triaxial compression test can be performed to determine the strength parameters. However, it is very difficult to obtain the representative undisturbed samples on the site and also the rock specimen cannot represent rock mass including discontinuities, fracture zone, etc. This study aims to investigate the strength and deformation characteristics of granite masses corresponding to its weathering and develop a practical strength parameter evaluation method using the results of PMT. To predict weathering intensity and strength parameters of the weathered granite masess in the field, various laboratory tests and in-situ tests including field triaxial test and PMT are carried out. Based on the results of weathering index tests, the classification method is proposed to identify the weathering degree in three groups for the weathered granite masses. Using the analytical method based on the Mohr-Coulomb failure criteria and the cavity expansion theory, the strength parameters of rock masses were evaluated from the results of PMT. It shows that weathering intensity increases with decreasing the strength parameters exponentially. The strength parameters evaluated with the results of PM almost coincide with the results of field triaxial test.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.199-200
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• 2009

자연스러운 대화가 가능한 인공지능 대화시스템을 구축하기 위해서는 사용자의 문장에 내재된 감정을 이해할 수 있는 시스템이어야만 한다. 또한 상호간의 대화를 통해서 풍겨지는 분위기를 파악할 수 있다면 사용자에게 마치 인간과 대화하는 듯한 자연스러움을 느끼도록 할 수 있을 것이다. 실제 대화에서 감정은 언어적인 표현뿐 아니라 비언어적인 표현으로도 표출되지만, 본 논문은 텍스트 상에서 언어적으로 표현되는 감정 정보를 인식하는데 초점을 둔다. 언어적인 표현으로 한정하여 감정을 인식하는 경우에는 감정을 직접 표현하고 있는 형용사나 동사가 중심이 된다. 본 논문에서는 형용사를 중심으로 하여 화행 정보와 결합하여 감정을 인식하는 시스템에 대해서 제시하고자 한다. 이 논문은 문장에 내재되어 있는 숨겨진 감정이나 분위기 등을 파악하기 위한 연구에 대한 선행 연구로서 텍스트 상에서 직접 드러나는 감정을 인식하기 위한 방법을 제안한다.

• Bulletin of the Society of Naval Architects of Korea
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• v.31 no.3
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• pp.25-27
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• 1994

선박의 고속화, 경량화, 전문화 및 대형화의 촉진과 더불어 신형식 선박의 출현으로 기존의 해 석방법과 같은 개념으로는 새로운 문제점에 대한 해결이 불가능하다. 따라서 이와 같은 새로운 외력환경에 대한 신형식 선박에 구애받지 않고 범용으로 이용이 가능할 수 있게 하기 위해서는 하중의 공간적 분포와 시간적 변화에 대한 정보를 정도 높게 추정할 수 있는 방법이 바람직하 다고 본다. 이를 해결할 수 있는 유일한 방법은 우리가 지금까지 소흘하여 왔던 반복적 실험이 뒷받침되어, 수치이론의 모델화 과정에서나 물리현상 설정과정에서 내재하게 되는random한 불확실성을 정량적으로 파악해 두어야 신형식 선박 개발에 신뢰할 수 있는 동적 응답해석이 가 능해질 것이다.

• Proceedings of the Costume Culture Conference
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• 2003.04a
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• pp.45-46
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• 2003

지난 30년 동안 서구과학계는 엄청난 변화의 물결이 일어났다. 과학은 무미건조하고 어떤 감동도 주지 못하며 예술과는 거리가 멀다고 생각해 왔다. 그러나 과학과 예술과 함께 자연을 경험하는 두 가지 상호 보완적인 방법의 하나로서 최근 자연 속의 복잡한 모양이 내재하는 규칙을 이해하려는 프렉탈 과학을 통하여 과학과 예술간의 실제적 접목이 여러 가지 방향으로 시도되고 있다. 우리의 미적 감각은 자연에 나타나는 질서와 무질서의 조화로운 배열에 의해서 영감을 받는다. (중략)

• Journal of the Korean Society for Computer Game
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• v.31 no.4
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• pp.91-99
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• 2018

A growing body of research has focused on the negative effects of Internet gaming. This issue has become an increased public health concern in Korea. However, little is known regarding the positive effect of Internet gaming and its etiology. This study examined the effects of gaming motivations on gaming behaviors based on self-determination theory. Specifically, we investigated the associations of intrinsic and extrinsic gaming motivations with adaptive and maladaptive game uses. A cross-sectional data collected from a sample of 3,000 young adults using 2016 Korean Video Gaming Survey was analyzed. Measurement model analysis and structural equation modeling were conducted as primary analyses. The findings highlight the different effects of intrinsic and extrinsic motivations on gaming behaviors, such as adaptive and maladaptive game uses. Intrinsic motivations, such as experience-seeking and achievement-seeking, were associated with adaptive game use. Meanwhile, extrinsic motivations, such as sensation-seeking and monetary reward-seeking, were associated with maladaptive game use. The findings provide a better understanding of video gaming in light of both adaptive and maladaptive game uses. The implications for practice and policy were discussed.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.05a
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• pp.456-459
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• 2022

본 연구는 최근 자연어 인공지능 연구 동향에 발맞추어 사전 학습된 언어 인공지능을 활용한 의미론적 분석을 통해 국문 보고서의 가독성을 평가하는 방법론 두 가지를 제안한다. 연구진은 연구 과정에서 사전 학습된 언어 인공지능을 활용해 추가 학습 없이 문장을 임의의 벡터값으로 임베딩하고 이를 통해 1. 의미론적 복잡도 와 2. 내재적 감정 변동성 두 가지 지표를 추출한다. 나아가, 앞서 발견한 두 지표가 국문 보고서의 가독성과 정(+)의 상관관계에 있음을 확인하였다. 본 연구는 통사론적 분석과 레이블링 된 데이터에 크게 의존하던 기존의 가독성 평가 방법론으로 부터 탈피해, 별도의 학습 없이 기존 가독성 지표에 근사한다는 점에서 의미가 있다.