• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.4 no.2
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• pp.65-71
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• 1992

In most absorption machines, absorption enhancement has been achieved by adding small amount of surfactant additive, which introduced the surface tension difference between absorbent and surfactant droplets in the vapor absorption. The aim of this study is to understand a basic mechanism of Marangoni convection and its effectiveness in the vapor absorption enhancement. In this study, nonflowing aqueous solution of LiBr 60 mass% was exposed to saturated water vapor under the condition that two dropwises surfactant were fixed on the absorbent surface. Our experiments achieved to visualize the enhanced heat and mass transfer phenomena by the effect of Marangoni convection through the laser holographic interferometry. Also, Marangoni convection behavior was obtained by using tracer method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.4
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• pp.487-496
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• 1985

회전하는 축대칭 얇은 셸구조물의 진동 특성을 유한요소법에 의하여 해석하였다. 2개의 절점을 가진 Conical Frustrm 형태의 축대칭 요소를 사용하였으며 원주방향의 변위는 Fourier Series로 분해하여서 방정식의 수를 상당히 줄일 수 있었다. Sanders-Koiter의 셸이론을 사용하였으며 진 동 모우드는 회전의 영향을 설명하기 위하여 대칭 및 비대칭 모우드를 모두 고려하였다. Coriolis 행렬을 포함하는 운동방정식에서 고유 진동수를 계산하기 위해서 질량, 강성 및 Coriolis 행렬로 이루어지는 Hermitian 행렬의 Sturm Sequence Property를 이용하였으며, 좁은 밴드를 갖는 대형 행렬에 알맞는 Determinant Search 방법을 확장하여 고유진동수 및 벡터를 구하였다. 원통형 셸에 대하여 정지한 경우 계산한 고유진동수를 실험치 및 이론치와 비교한 결과 잘 일치됨을 알 수 있었다. 여러 가지 회전 속도에 대해서 얻어진 고유진동스를 이론치와 비교한 결과 잘 일치 됨을 알 수 있어\ulcorner며 회전의 영향으로 traveling wave진동의 현상이 나타남을 알 수 있었다.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.4
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• pp.97-106
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• 1996

The impact response of the human brain has been determined by three-dimensional finite element modeling. The model includes a layered shell closely representing the cranial bones with the interior contents occupied by an incompressible contimuum to simulate the brain. Flax and tentorium modeled with 4 node membrane element were also incorporated. The computed pressure-time histories at 4 locations within the brain element compared quite favorably with previously published experimental data from cadaver experiments. A parametric study was subsequently conducted to identify the model response when the impact were varied.

• The Korean Journal of Rheology
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• v.3 no.1
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• pp.56-67
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• 1991

압출공정에서 발생하는 전달현상을 이해하기 위하여 싱글-스크류 압출기에서의 비 뉴톤성 유체의 비등온유동에 대한 수치해석을 위한 유한요서법(FEM)을 개발하였다. FEM 은 준-3차원 물리적 모델을 기본으로 하였고 온도분포해석을 위하여 전진방법을 도입하였 다. 본 연구에서 도입한 수치해석적 모델과 더 간단한 준-2차원 모델을 온도분포의 예측에 관하여 초점을 맞추어서 비교 하였다. 압출기의 내부채넬에서 순환유동이 온도분포에 미치 는 영향의 중요성이 강조되었다. 순환유동의 효과를 파악하기 위하여 유한 요소식에서 순환 과 관련된 대류항을 빼도록 유한요소 프로그램을 개조 하였고 개발된 원래의 프로그램과 개 조된 프로그램의 해석을 수행한후 해석결과 중에서 특히 온도분포에 있어서의 차이점을 비 교하였다. 이로부터 간단한 준-2차원 모델은 순환효과를 무시했기 때문에 속도분포의 예측 에서는 별문제가 없으나 온도분포의 예측에 있어서는 크게 잘못될 수 있음을 알수 있다.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.10
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• pp.98-106
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• 1996

This paper proposes an algorithm for analyzing illocutionary force type (IfT)s in a dialogue, based on the context and modal information in the ending of a word. In korean, the variation of an illocutionary force type that represents a speaker's intention frequently occurs at the ending of a word, according to the type of modal information. And in an analysis of speech acts, the modal information illocutionary force types. In this paper, we analyze real dialogue dta, classify the types of illocutionary forces, perform the manual tagging of IFTs and show the freqency of each IFT's occurence. And we also propose an algorithm to extract IFTs, based on the relationship between the analyzed IFTs and the endings of a word. And we use this proposed algorithm to make an experiment on dialogue data and show its efficiency.

• Annual Conference on Human and Language Technology
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• 2010.10a
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• pp.202-206
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• 2010

이 논문에서는 한국어 형태소 분석기 KMM(Korean Malaga Morphology)을 소개하고자 한다. KMM의 개발 동기는 이후 자연언어 처리 단계의 기반으로 사용될 수 있을 뿐 아니라 이론 형태론 연구의 도구로도 사용될 수 있도록 상세한 형태 동사 의미 정보를 제공하는 것이었다. 이론적 틀은 좌연접 문법(Left-Associative Grammar)에 기초한 LA-MORPH이며, 좌연접 기반 문법 개발 도구인 MALAGA로 구현되었다. LA-MORPH에 기반한 KMM은 분석 실행중이 아닐 때에는 사전의 규모를 최소한으로 유지하다가 분석에 필요할 때에만 분석용 사전을 자동으로 생성한다. 형태소 분석은 분석용 사전에 근거하여, 매칭과 결합이라는 단순한 알고리즘만을 사용한다. KMM의 분석은 동사 어절의 경우, 시제, 서법, 문형, 대우법, 명사 어절의 경우 격정보, 수사 결합어절의 경우 추출된 수랑 정보 등과 같은 상세한 정보를 제시한다. 세종 말뭉치와 KIBS 말뭉치를 KMM 을 이용해서 분석한 결과 각각의 94.96%와 94.59%의 분석률과 88.4%와 90.7%의 정확도를 보였다.

• Journal of the Korean earth science society
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• v.31 no.1
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• pp.51-62
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• 2010

The purpose of this study was to investigate how a science magazine played a role in filling the gap between scientists and the general public, and how it contributed to science popularization. We analyzed the linguistic features of the texts used in a science magazine. We used 12 articles (six written by journalists, and six written by scientists) from the Science Donga. Register analysis was conducted in order to define the linguistic features of the texts in terms of ideational meaning, interpersonal meaning and, textual meaning. Results of this study are as follows: (1) the articles written by journalists used a higher mental and verbal processes in which the conversations and thoughts of scientists were expressed. (2) Human agents were relatively explicit in the journalists' articles. However, they were implicit or omitted in the articles of scientists. (3) Interrogative sentences and inclusive imperative sentences, and even omissions were frequently found in the journalists' articles whereas scientists' articles mainly used declarative statements. (4) The clause density of journalist' articles and scientists' were similarly lower than that of science textbooks. (5) The information structure revealed by the patterns of Theme and Rheme that the journalists' articles used in science magazines was simpler than that of science textbooks, while the structure of scientists' articles was more complex than that of journalists'. Based on the linguistic features of the texts used in science magazines, we found that a science magazine contributes to science popularization in two faces: One is in that the articles of journalists present science contents in a way that the readers can follow with ease and feel well-acquainted. The other is that the modified articles of scientists help the general public get familiar with the culuture of science in terms of use of science language.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.179-186
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• 2020

Wongyo Lee KwangSa (1705~1777) is a scholar and artist who represented an era in the period of change and revival of Korean culture and art in the 18th century. In 1755 (31st Yeongjo), he was transferred to Sinjido due to the Naju Byeokseo Incident, and died in exile for a total of 23 years. He tried to correct the problems of the flow of calligraphy in common writing and the flow of calligraphy in the Joseon Dynasty, and wrote 『Wonkyo Seogyeol』. By realizing an original artistic state that is evaluated as having completed the 'Dongguk Jinche', which is a unique and subjective and self-conscious calligraphic flow of the Korean people who wants to reestablish the essence of calligraphy, it has had an absolute influence on the Honam area. Wonkyo's calligraphy aesthetics are developed into the beauty of ChanggyeongBalsog based on Shimjin of Yangminghak, Yanggangmi of Power of controlling all the stands of brush hair, and Vitality of Push out the brush with all your might. He recognized free sculpting and energetic, muscular strokes as the key to calligraphy, and suggested honing the old tombstones written in JeonYe. Vibrant stroke means that Cheongi naturally permeates in the midst of Samgwa and Gilgok, and the brush is operated with Push out the brush with all your might of Power of controlling all the stands of brush hair. These calligraphy aesthetics radiated sinchae with geungol and singi, and were expressed in Wongyo font, full of vitality as a living creature, pursuing the unique pilgrimage and pilgrimage unique to our nation, revealing the true nature of nature.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.24 no.2
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• pp.289-313
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• 2013

The purpose of this study is to improve the information literacy of elementary school students. For the study, three 4th grade classes of an elementary school in Daegu were provided a two-hour instruction about basic training on how to utilize information and school library, after which one of the three classes received 2 hours long weekly information literacy instructions associated with social studies and science curriculum for 20 weeks. The study, implemented in two phases with mid-term assessment, involved three interview sessions with students, two interview sessions with homeroom teachers, a general descriptive survey, a performance assessment and a follow-up survey.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.6
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• pp.584-589
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• 2009

As the automobile energy efficiency stands out an important matter of interest, the magnetic engine valve system receives attention. It has an advantage of no engine power leakage in opening and closing the valve. Moreover, it generates much bigger force than the piezo actuator system, so it can be a good alternative system of the cam and camshaft system. However, since the valve system is not light enough, it is necessary to make its weight reduce. In this study, topology optimization is applied to find the optimal shape of the armature in a magnetic valve system combined with the finite element analysis for the magnetic field analysis. The result is used to obtain a concept design. The adjoint variable method is employed in order to calculate the design sensitivity of the magnetic driving force in the armature component mostly to reduce the computational time during the repeated sensitivity calculation. The sequential linear programming is employed for the optimization algorithm.