• Title/Summary/Keyword: 동조성

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한국형 e-Navigation 선내시스템 원격 모니터링 서비스의 복원성 및 화재 판정 모듈 개발

  • Lee, Dae-Hak;Lee, Sang-Man;Choe, Jeong-Ung;Lee, Seung-Hyeon;Park, Jin-Hyeong;Kim, Seung-Tae
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2019.11a
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    • pp.165-167
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    • 2019
  • 본 연구에서는 한국형 e-Navigation 선내시스템 원격 모니터링 서비스(SV20) 중 복원성 및 화재 판정 모듈의 개발과 운용개념에 대해서 소개하였다. 구체적으로는 선박의 복원성(안정성)과 관련된 메타센터 높이(GM), 복원성지수, 운동성지수 그리고 선체-파랑 동조위험성의 산출 및 표출에 대한 방안과 선내 화재정보의 표출 방안을 설명하고, 개발 진행사항 그리고 향후 연구 등을 기술하였다.

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Case Study on Combustion Stabilization in FASTRAC Thrust Chamber Using Acoustic Cavities (FASTRAC 연소기에서 음향공을 이용한 연소불안정 제어 사례 연구)

  • Kim, Hong-Jip;Kim, Seong-Ku
    • Journal of the Korean Society of Propulsion Engineers
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    • v.16 no.5
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    • pp.29-36
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    • 2012
  • 3-D linear acoustic analysis has been performed to elucidate damping characteristics of large Helmholtz acoustic cavities in FASTRAC thrust chamber. Acoustic impedance concept has been introduced to quantify combustion stabilization capacity. For a given acoustic cavity, sonic velocity in the cavity to achieve an optimal tuning has been determined and satisfactory agreement with the previous results has been obtained. Feasible estimation of sonic velocity in the acoustic cavity has been devised. Results show similar trends without significant deviations, which can be used in the procedure of design and verification of acoustic cavity. From the satisfactory results, investigation of other thrust chambers with acoustic cavities which have shown combustion instabilities will be done as future works.

Effects of Appearance Interest and Demographic Characteristics on Clothing Conformity (외모 관심과 인구통계학적 변인이 의복 동조성에 미치는 영향)

  • Park, Kwang Hee;Yoo, Hwa Sook
    • Fashion & Textile Research Journal
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    • v.15 no.2
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    • pp.210-218
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    • 2013
  • This study examined the degree of appearance interest and clothing conformity, the impacts of appearance interest on clothing conformity, and the effects of appearance interest and demographic variables on clothing conformity. A questionnaire survey collected data from October $3^{rd}$ to $27^{th}$ 2011. A convenience sample was drawn from adults between the ages of 17 and 76 who lived in the Daegu and Gyeongbuk regions of South Korea. A total of 513 responses produced complete and usable questionnaires. Data were tested through factor analysis and regression analysis, using SPSS 20.0. The results of this study are as follows : First, three factors were extracted from clothing conformity (normative, informative, identifiable conformity). The appearance interest was relatively high and normative conformity was the highest level among three factors of clothing conformity. Second, appearance interest was significant predictors of clothing conformity. Third, demographic variables such as gender, marital status, age and education levels had significant effects on the relationship between appearance interest and clothing conformity.

Adaptive Digital Watermarking with Perceptually Tuned Characteristic Based on Wavelet Transform (웨이브릿 변환영역에서 지각적 동조특성을 갖는 적응적 디지털 워터마킹)

  • 김현천;장봉주;서용수;김종진
    • Journal of Korea Multimedia Society
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    • v.6 no.6
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    • pp.1008-1014
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    • 2003
  • In this paper, we propose the image retrieval method based on object regions using bidirectional round filter in the wavelet transform domain. A conventional method that includes unnecessary background information reduce retrieval efficiency, because of the extraction of feature vectors from the whole region of subband. On proposed method, it extracts accurate feature vectors and keep certainly retrieval efficiency in case of reduced feature vectors, because of the extraction of feature vectors from the only extracted object region. Furthermore, it improve retrieval efficiency by removing unnecessary background information. Consequently, the retrieval efficiency is improved with 2.5%∼5.5% values, which have a little chances to vary according to characteristics of image.

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A new type liquid damper with adjustable natural frequencies (고유진동수 조절이 가능한 새로운 형태의 액체댐퍼)

  • Lee, Hye-Ri;Min, Kyung-Won;Park, Ji-Hun
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2011.04a
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    • pp.161-165
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    • 2011
  • 본 논문에서는 고유진동수 조절이 가능한 새로운 형태의 액체댐퍼를 개발하였다. 동조댐퍼는 구조물의 설계단계에서 응답평가를 통해 필요성이 요구된다. 건물은 설계단계에서 고유진동수와 시공 후 고유진동수가 상이하다. 액체댐퍼의 형태는 설계단계에서 건물의 고유진동수를 동조시킬 수 있도록 설계되기 때문에 고유진동수가 고정이 될 수 있다. 본 연구에서는 제안한 댐퍼의 전체적인 형태는 기존의 Liquid Column Vibration Absorber(LCVA)와 같다. 기존의 LCVA는 시공 후 건물의 고유진동수에 동조시키기 위해 물높이를 조절하나 층고 때문에 제한이 있다. 우리가 제안한 새로운 형태의 액체댐퍼는 물높이 조절 뿐 아니라 수직관의 면적을 조절하여 고유진동수를 조절 할 수 있도록 개발하였다. LCVA의 수직관을 일정한 면적의 독립된 셀로 나누었으며 이 셀을 각각 밀폐시킬 수 있도록 하였다. 밀폐된 셀 안으로는 공기압력에 의해 물이 차지 않고 차 있는 물도 움직이지 않게 된다. 밀폐된 셀의 개수를 조정하여 수직관의 면적이 조절하여 고유진동수를 변화시킬 수 있다. 제작된 액체댐퍼의 밀폐된 셀 개수를 조절하여 진동대 실험을 통해 댐퍼의 고유진동수를 파악하였다. 실험으로 나온 고유진동수와 이론적으로 산정한 고유진동수를 비교하여 댐퍼의 사용성을 평가하였다. 개발된 액체 댐퍼의 수직관의 면적 조절을 통해 고유진동수 조절이 용이하여 실제로 사용이 가능함을 확인할 수 있었다.

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Case Study on Combustion Stabilization in FASTRAC combustor using Acoustic Cavities (FASTRAC 연소기에서 음향공을 이용한 연소불안정 제어 사례 연구)

  • Kim, Hong-Jip;Kim, Seong-Ku
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2012.05a
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    • pp.16-23
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    • 2012
  • 3-D linear acoustic analysis has been performed to elucidate damping characteristics of large Helmholtz acoustic cavities in FASTRAC combustor. Acoustic impedance concept has been introduced to quantify combustion stabilization capacity. For a given acoustic cavity, sonic velocity in cavity to achieve an optimal tuning has been determined and satisfactory agreement with the previous results has been obtained. Feasible estimation of sonic velocity in acoustic cavity has been devised. Results show similar trends without significant deviations, which can be used in the procedure of design and verification of acoustic cavity. From the satisfactory results, investigation of other combustors with acoustic cavities which have shown combustion instabilities will be done as future works.

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An Analysis of Stock Return Behavior using Financial Big Data (금융 빅 데이터를 이용한 주식수익률 행태 분석)

  • Jung, Heon-Yong;Kim, Sang-Sik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.708-710
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    • 2014
  • 최근 금융 분야에서는 빅 데이터를 이용하여 주가예측 모형을 만들어내고 있으며, 특히 금융 시계열 자료의 변동성 집중 현상을 금융 빅 데이터를 이용하여 분석함으로써 세계 주식시장의 동조화 현상을 분석하고 있다. 본 논문에서는 한국과 중국의 일별 주가지수수익률과 일중 주가지수수익률을 이용하여 이들 2개 국가의 대표적인 주가지수 시계열 데이터에 변동성 집중 현상이 존재하는지를 보다 세밀하게 추적하여 양국 주식시장의 동조화 현상을 분석한다. 분석 결과, 한국의 KOSPI와 중국의 Shanghai 종합주가지수의 지수수익률 시계열 자료는 단위근이 존재하지 않으며, 변동성 집중 현상을 보이는 것으로 나타났다. 또한 한국보다는 중국 주식시장의 변동성 집중현상이 보다 강하게 나타나며, 이러한 현상은 일중 주가지수수익률 시계열 자료에서 보다 두드러지게 나타났다.

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Analysis of Investment Behavior : From the Perspective of Capital Market Comovements (투자주체별 투자행태 분석 : 한미 주가동조화를 중심으로)

  • Jun, Sang-Gyung;Choi, Jong-Yeon
    • The Korean Journal of Financial Management
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    • v.20 no.2
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    • pp.127-150
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    • 2003
  • This study analyzes how capital market comovement can affect investors' decision making. We first analyze time-varying correlation coefficient between stock indices of U.S.A. and Korea. and then, using our empirical results, attempt to draw implications on investors' behavior. We find that the tendency of comovement between Korea and U.S.A. equity returns has considerably increased after the financial crisis of late 1997. Through the analysis of investors' behavior, we find that foreign investors, contrary to ITC's (Investment Trust Company) and individual investors, buy more shares in Korean markets as American stock prices go up. Foreign investors employ dynamic hedging strategy and give more weight on global economic factors than domestic ones. Our empirical results as a whole imply that investment behavior of foreign investors is most closely related to comovement of U.S.A. and Korea capital markets.

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Morphological Traits of Trisomic Plant in Durum Wheat (듀럼밀 3염색체 식물의 형태적 특성)

  • 오세관
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.42 no.4
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    • pp.392-402
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    • 1997
  • The morphological traits of different types of primary trisomics(2n=28+1) in durum wheat, Triticum durum var. hordeiforme(2n=28 AABB) were compared with disomics (2n=28) through the examination of reciprocal gene action on the extra chromosomes. However it was not easy to distinguish morphologically the trisomies containing A genome from those containing B genome. These results suggested that the chromosomal location of the major genes for some morphological traits exists on homoeologous chromosome. It is important that these results revealed the homoeology and linkage groups of both A and B genomes in durum wheat. These primary trisomies will be valuable materials for the trisomic analysis and genetic mapping on the chromosome of both A and B genomes in durum wheat. Furthermore, it must be useful for the evolutionary study of Triticum durum(AABB) and Triticum squarrosa(DD) by way of the ancester species of Triticum aesitivum(AABBDD).

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When Do Consumers Follow Majority Choice? - Different Effect of Purchase versus Usage Situation - (어떤 상황에서 소비자는 다수의 선택을 따를까? - 구매상황과 사용상황이 미치는 상이한 영향을 중심으로 -)

  • Kim, Moon Seop;Oh, Hyunmin;Kim, Jae Il
    • Asia Marketing Journal
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    • v.12 no.1
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    • pp.31-50
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    • 2010
  • People have competing desires. Hence, people not only chase others' choices due to the need for assimilation but also avoid others' choices due to the need for differentiation. This study attempts to uncover under which conditions consumers assimilate with or differentiate from others' choices. Specifically, the study extends previous research about the effect of others' choices by focusing on the effect of a choice situation (purchase vs. usage) based on the conformity theory and the uniqueness theory. It was found that purchase (vs. usage) situation makes people more conform to others in case of identity-irrelevant product (e.g., USB memory stick). Also, the effect of the choice situation was moderated by the perceived identity-relevance level in case of identity-relevant product (e.g., jeans).

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