• Journal of Korean Society of Steel Construction
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• v.30 no.1
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• pp.49-58
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• 2018

This study conducted nonlinear finite element analysis to figure out the influence of shear performance on the ${\beta}$ of girders with trapezoidal corrugated web. Through the experiment specimen, analysis model which is highly accurate was verified. Based on this, a parameter analysis was conducted on key variables affecting ${\beta}$. Proposed formulas of previous studies were analyzed using parameter analysis result. Eurocode was designed to be safer than other proposals. Only models that are included in the inelastic area, depending on the Moon's proposal, were satisfied the proposed formulas by Kim to enhance economic design.

• Composites Research
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• v.22 no.1
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• pp.22-31
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• 2009

Recently the wind energy has been alternatively used as a renewable energy resource instead of the mostly used fossil fuel due to its lack and environmental issues. This work is to propose a structural design and analysis procedure for development of the 500W class small wind turbine system which will be applicable to relatively low speed region like Korea and for the domestic use. The wind turbine blade was performed structural analysis including stress, deformation, buckling, vibration and fatigue. In addition, the blade should be safe from the impact damage due to FOD(Foreign Object Damage) including the bird strike. MSC.Dytran was used in order to analyze the bird strike penomena on the blade, and the applied method Arbitrary Lagrangian-Eulerian was evaluated by comparison with the previous study results. Finally, the structural test was carried out and its test results were compared with the estimated results for evaluation of the designed structure.

• Journal of the Geological Society of Korea
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• v.54 no.6
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• pp.631-640
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• 2018

To understand the formation and evolution of a sedimentary basin in basin analysis and modelling studies, it is important to analyze the thickness and age range of sedimentary layers infilling a basin. Because the compaction effect reduces the thickness of sedimentary layers during burial, basin modelling studies typically restore the reduced thickness using the relation of porosity and depth (compaction trend). Based on the compilation plots of published compaction trends of representative sedimentary rocks (sandstone, shale and carbonate), this study estimates the compaction trend ranges with exponential curves and equations. Numerical analysis of sedimentary compaction is performed to evaluate the variation of porosity and layer thickness with depth at key curves within the compaction trend ranges. In sandstone, initial porosity lies in a narrow range and decreases steadily with increasing depth, which results in relatively constant thickness variations. For shale, the porosity variation shows two phases which are fast reduction until ~2,000 m in depth and slow reduction at deeper burial, which corresponds to the thickness variation pattern of shale layers. Carbonate compaction is characterized by widely distributed porosity values, which results in highly varying layer thickness with depth. This numerical compaction analysis presents quantitatively the characteristics of porosity and layer thickness variation of each lithology, which influence on layer thickness reconstruction, subsidence and thermal effect analyses to understand the basin formation and evolution. This work demonstrates that the compaction trend is an important factor in basin modelling and underlines the need for appropriate application of porosity data to produce accurate analysis outcomes.

• 전기의세계
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• v.27 no.5
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• pp.33-54
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• 1978

(차례) 1.산학협동심포지업 (1)우리나라에서의 연구개발과 산학협동 (2)산학협동과 산업계의 역할 (3)산학협동의 현황과 진로 2.학술회의A (1)전력게통의 계층구조와 협조원리에 관한 연구 (2)2중층괴상회전자 유도전동기의 이론해석 (3)초고주파가열장치에 사용하는 철공진변압기의 해석적 설계 (4)한국전기기시험연구소 대전력단락 시험설비설계 (5)직류전동기제어를 위한 Thyristor Chopper정류회로에 관한 연구 (6)선로의 개폐정보를 포함하는 전력계통의 상태추정 (7)단일신경세포에 대한 ITEM 신호 특성 3.학술회의B (1)MMM-1 Computer System의 설계 및 제작 (2)Adaptive Delta Modulation System의 성능비교 연구 (3)6GHZ FMD마이크로파 무선전송장치의 개발 (4)적선도에 의한 회로망함수의 결정 (5)동맥혈압의 해석과 그의 전기적 유사모델 (6)피부감각의 정보전달 특성에 관하여 (7)선형직접회로의 공정설계 및 그 특성 조성 (8)DH L.D의 전기적포화현상에 관한 이론적 해석 (9)Potocoupler를 이용한 Isolator 4.학술회의C (1)Al-Al$_{2}$O$_{3}$ -Al박막구조의 전기적 특성 (2)이종금속에 샌드위치된 고분자물질의 단락전조 (3)유전체가 일부체워진 직 6면체의 캐비티의 다중모오드 해석 (4)반도체 가스 검지소자의 제조 및 그의 전기적 특성 (5)실리콘 산화공정에 대한 실험적 고찰 (6)진공증착법에 의한 InSb 박막제도에서 열처리효과 (7)(Ba$_{1}$-xBix) Tio$_{3}$ PTC thermistor의 첨가량의 최적건안 (8)금속박막증착시 두께조절 5.특별강연회 (1)일본에 있어서의 절력계통공학연구 (2)Linear Motor의 최근개발동향량도 높았다. valine과 leucine 및 aspartic acid, glycine과 glutamic acid, leucine과 aspartic acid 간에는 고도의 정상관, glycine과 serine, valine과 phenylalanine, threonine과 proline, phenylalanine과 arginine, methionine과 glutamic acid, histidine과 lysine 간에는 유의 정상관, 그리고 isoleucine과 lysine 간에는 유의한 부상관이 있었다. 4. lysine 함량은 단백질 함량과 정산곤, isoleucine 함량은 단빅질 함량과 부상관을 보였으며, alanine, valine, leucine 함량은 지방함량과 각각 유의한 정산관을 보였다. 5. 대두 단백질은 7.5% acrylamide gel 전기영동에 의해 품종에 따라 12～16개의 구성분으로 분리되었으며, 이들중 주구성분들은 상대이동도가 0.06(a), 0.14(b). 0.24(d) 이었고, 구성분 b의 함량이 품종간에 가장 변이가 컸으며, 구성분 b는 그밖의 주요 구성분들의 함량과 부의 상관이 있었고, 구성분 a는 단백질 함량과 정상관이 있었다. 6. 종실단백질 구성분들의 조합 특성 면에서 공시 86품종은 11개 유형군으로 분류되었으며, 우리나라와 일본품종은 미국품종에 비해 단백질구성분 조성이 훨씬 다양하였다. 7. 이동도가 매우 빠른 단백질 구성분 o(Rm 0.77) p(Rm 0.81)를 모두 갖고 있는 품종은 3품종, 모두 갖고 있지 않은 품종은 1품종이었고, 나머지 82품종은 o나 p중 한 구성분을 갖고 있었으며 그 분포율은 30 : 65 이었는데 미국계 품종은 우리나라 품종에 비해 구성분 o를 간고 있는 비율이 현저히 적었다. 8. 대두 종실은 개화후 22일까지 완만히, 그 이후 20～30일간 급속히

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.169-174
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• 2019

Because the warm and cozy demand of automotive driving seat increases, the research development of heating seat has been actively made. In this study, the thermal stress analysis and the structural analysis were carried out with three kinds of heating seats of A, B and C. By executing the thermal analysis with the same material, model A was shown to have the heat transfer better than model B or model C at the study result. So, it could be seen that the heat transfers became different each other though models had the same material according to the configuration of product. Adding the hot wire in order to expect the safer heating can be better heating, but there is the limit on the aspect considering the capability in contrast to the price of product. Generally, model B is thought to be safest thermally than model A or model C in every respect. As the design data of the automotive heating seat product with the durability and safety acquired by this study result are used, the artistic environment can be promoted by being grafted onto the automotive driving seat.

• School Mathematics
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• v.5 no.1
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• pp.135-149
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• 2003

We present an understanding about students' conceptual model of differential equations, based on the discourse data that were collected in a differential equations course at a university in Korea. An interpretive approach is taken to analyze classroom discourse. This paper consists of three main parts. First, we completely analyze the students' use of conceptual metaphor in a university differential equations class. Secondly, we identify conceptual metaphors representing students' conceptual model of differential equations. Finally, we describe the mathematical characteristics of the conceptual metaphors identified in detail. Among other things, this paper reveals that there exists dual aspects of the students' conceptual model of differential equations. In other words, in the differential equations course observed we found that the students very often used two kinds of conceptual metaphor,“machine metaphor”and“fictive motion metaphor”, that have contrastingly different mathematical characteristics. In order to interpret the duality, we take a sociocultural perspective, and this perspective suggests and helps us to realize the significance of understanding of cognitive diversity in mathematics classroom.

• Journal of The Korean Association For Science Education
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• v.36 no.4
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• pp.607-616
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• 2016

In the 2009 revised science curriculum, comprehensive verbs such as 'know (38%)' and 'understand (46%)' are used in more than 80% of the achievement standard. Many readers, such as teachers, textbook makers, etc. have difficulties in interpreting the meaning of achievement standard sentences with these comprehensive verbs. On the other hand, 'Trends in International Mathematics and Science Study (TIMSS)' uses more various and specific verbs to express the cognitive domain. In this study, we analyzed the 2009 revised science curriculum achievement standard focusing on the TIMSS cognitive domain assessment framework. We divided achievement standard to 228 sentences and three teachers analyzed the meaning of verbs in achievement standard. There were two main results of this study. First, the verb 'Know' was analyzed into different kinds of meanings, such as 'Describe (27%)', 'Recall/Recognize (25%)' and 'Relate (17%)', etc; and the verb 'Understand' was analyzed into 'Explain (37%)', 'Relate (27%)' and 'Describe (21%)', etc. Second, there appeared to have a disagreement among the three analysts during the process of interpreting the achievement standards when the level and scope of the contents of each grade is not clear. This study concludes that there's a need for continuous discussion on the use of verbs in achievement standard to promote clearer expressions for better understanding.

• Journal of the Korean Society for information Management
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• v.21 no.4 s.54
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• pp.265-279
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• 2004

This study is to research quintessence of information service in the libraries by interpreting 'Information' as it is ubiquitous. For the purpose, it investigates and analyzes information behaviors of the libraries in information-cultural history. The meaning of 'ubiquitous' is understood as a practice that everything we need should be inherent in our lives for its usefulness and effectiveness. Information is intrinsic in our lives and the libraries, information management systems, have been evolved by extending the intrinsic value of information, 'ubiquity'. Human being's history results from information behaviors and the meaning of the libraries consists of production, accumulation, organization and distribution of the libraries. It should be recognized that the ultimate purpose of the library services is for their users. Consequently information systems and technological networks in the libraries should be focused on applications and inherence for the purpose. Model studies of the libraries should be developed to user-centered information services that substantialize the interpretation of information, as it is ubiquitous. This study is a trial for defining the quintessence of the libraries. Furthermore, it provides foundation of understanding what the libraries are.

• Journal of Internet Computing and Services
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• v.5 no.3
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• pp.35-43
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• 2004

In packet switching using multistage interconnection networks (MIN's), it is generally assumed that the packet movements successively propagate from the last stage to the first stage in one network cycle. However, Ding and Bhuyan has shown that the network performance can be significantly improved if the packet movements are confined within each pair of adjacent stages using small clock cycles. In this paper, an analytical model for evaluating the performance of input-buffered MlN's employing this network cycle approach is proposed, The effectiveness of the proposed model is confirmed by comparing results from the simulation as well as from Ding and Bhuyan model.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.98-98
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• 2023

ChatGPT(Chat과 Generative Pre-trained Transformer의 합성어)는 사용자와 주고받는 대화의 과정을 통해 질문에 답하도록 설계된 대형언어모델로, 지도학습과 강화학습을 모두 사용하여 세밀하게 조정된 인공지능 챗봇이다. ChatGPT는 주고받은 대화와 대화의 문맥을 기억할 수 있으며, 보고서나 실제로 작동하는 파이썬 코드를 비롯한 인간과 유사하게 상세하고 논리적인 글을 만들어 낼 수 있다고 알려져있다. 본 연구에서는 수자원시스템분야의 문제해결에 있어 ChatGPT의 적용가능성을 사례기반으로 확인하고, ChatGPT의 올바른 활용을 위해 필요한 사항에 대해 고찰하였다. 수자원시스템분야의 대표적인 연구주제인 상수관망시스템의 누수인지와 수리해석을 통한 문제해결에 ChatGPT를 활용하였다. 즉, 딥러닝 기반의 데이터분석을 활용한 누수인지와 오픈소스기반의 수리해석 모델을 활용한 관망시스템 적정 분석을 목표로 ChatGPT와 대화를 진행하고, ChatGPT에 의해 제안된 코드를 구동하여 결과를 분석하였다. ChatGPT가 제시한 코드의 구동결과를 사전에 연구자가 직접 구현한 코드구동 결과와 비교분석하였다. 분석결과 ChatGPT가 제시한 코드가 보다 더 간결할 수 있으며, 상대적으로 경쟁력 있는 결과를 도출하는 것을 확인하였다. 다만, 상대적으로 간결한 코드와 우수한 구동결과를 획득하기 위해서는 해당 도메인의 전문적 지식을 바탕으로 적절한 다수의 질문을 해야 하며, ChatGPT에 의해 작성된 코드의 의미를 명확히 해석하거나 비판적 분석을 하기 위해서는 전문가지식이 반드시 필요함을 알 수 있었다.