• 제목/요약/키워드: Similarity Measurement

검색결과 352건 처리시간 0.029초

액체로켓엔진용 산화제펌프 회전체의 하중 예측 (Thrust Estimation Acting on Rotor of LOX Pump for Liquid Rocket Engine)

  • 김대진;최창호
    • 한국추진공학회지
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    • 제19권6호
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    • pp.98-104
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    • 2015
  • 회전체의 과도한 하중은 펌프의 손상이나 수명 감소의 원인이 된다. 이에 액체로켓엔진용 산화제펌프의 안정성 확보를 위해 펌프 회전체에 작용하는 하중을 상사 시험을 통해 예측하였다. 축방향 하중은 펌프 외부에 설치된 축추력 측정 장치를 통해 간접적으로 계측하였으며, 반경방향 하중은 볼류트의 압력 분포를 토대로 계산하였다. 그 결과, 펌프의 유량이 작을수록 축방향 하중과 반경방향 하중 모두 증가하는 것으로 확인되었다. 그러나, 하중의 크기가 크지 않아 펌프의 안정성에 영향을 끼치지 않을 것으로 예측되었다.

자체 제작한 시험장에서의 GPR의 매설물 검출능력에 관한 측정 (Detectability Measurement of GPR for Buried Target in Self-Designed Test Field)

  • 손수정;신병철
    • 비파괴검사학회지
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    • 제20권4호
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    • pp.322-328
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    • 2000
  • 730MHz의 고정 주파수를 방사하는 3소자 안테나 방식의 GPR을 이용하여 자체 제작한 시험장 속에 매설된 다양한 시험편의 검출능력을 조사하였다. 여러 가지 상황에 대한 검출능력을 알아보기 위하여 매설물의 재질, 크기, 매설 깊이에 차이를 두어 실험을 수행하였다. 레이다파의 전파속도를 조절하여, B-scan상의 쌍곡선 패턴의 위치를 실제 매설한 깊이에 정확하게 위치하게 함으로써, 실험결과로부터 얻은 soil(dry)에서의 레이다파의 전파속도가 기존 data와 유사함을 확인하였다.

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인스타그램 해시태그를 이용한 사용자 감정 분류 방법 (A Method for User Sentiment Classification using Instagram Hashtags)

  • 남민지;이은지;신주현
    • 한국멀티미디어학회논문지
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    • 제18권11호
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    • pp.1391-1399
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    • 2015
  • In recent times, studies sentiment analysis are being actively conducted by implementing natural language processing technologies for analyzing subjective data such as opinions and attitudes of users expressed on the Web, blogs, and social networking services (SNSs). Conventionally, to classify the sentiments in texts, most studies determine positive/negative/neutral sentiments by assigning polarity values for sentiment vocabulary using sentiment lexicons. However, in this study, sentiments are classified based on Thayer's model, which is psychologically defined, unlike the polarity classification used in opinion mining. In this paper, as a method for classifying the sentiments, sentiment categories are proposed by extracting sentiment keywords for major sentiments by using hashtags, which are essential elements of Instagram. By applying sentiment categories to user posts, sentiments can be determined through the similarity measurement between the sentiment adjective candidates and the sentiment keywords. The test results of the proposed method show that the average accuracy rate for all the sentiment categories was 90.7%, which indicates good performance. If a sentiment classification system with a large capacity is prepared using the proposed method, then it is expected that sentiment analysis in various fields will be possible, such as for determining social phenomena through SNS.

여대생(女大生)들의 지수치(指數値)에 의한 체형(體型) 집단(集團)별 실제체형(實際體型)과 신체인식(身體認識)에 관한 연구(硏究) (Study of Real Somatotype and Perceived Body Classified by Body Index of College Women)

  • 이정순
    • 패션비즈니스
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    • 제11권5호
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    • pp.100-109
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    • 2007
  • The purpose of this research is to study the recognition of real somatotype and body of college women. The study was carried out by classifying somatotypes into three categories based on the body index; slim, normal, and obese somatotype. The subject of this study was 106 college women, and real measurement and survey were used. Data was analyzed by SPSS 12.0 and cross tabulation analysis, t-test, Anova, and correlation analysis were operated. The result is as follows. 1. The height of the subjects was 163.5cm, weight was 53.3kg, Rohrer index was 1.2, BMI was 19.9, Vervaeck index was 84.4 and the classification based on the body index belonged to the normal group. 2. The characteristics of groups divided by the body index are that slimmer groups is longer in length factor and smaller in the factors related with volume than other groups. The characteristics of groups classified by self-consciousness shows significant difference in all girth factors, back intersyce breadth, front intersyce breadth, neck to nipple length, and nipple to nipple breadth. 3. Conscious about the somatotype with using body index generally shows similarity. In the length factor including height, slim somatotype group is perceived as longer than normal somatotype group, and in the girth factor including weight, normal somatotype group is recognized as bigger and thicker than others.

SKT 에서 파트너와 함께 춤을 : RMM 모형과 SKT 사례 적용 (Dancing with Partners at SKT: RMM Model with SKT case)

  • 권태형;방석범;이강업;최재웅
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2006년도 추계학술대회
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    • pp.3-16
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    • 2006
  • In the age where the Internet changes everything, even the earth has become flat. The boarders between nations, locations, times, and industries are not maningful, and no single company can do the whole process well. Therefore, various types of 'Value network' and 'Relation web' emerge for moving first and fast learning. Bort the relationship maturity model (RMM) proposed and the partnership management initiatives at SKT demonstrate that the concept is important, and that the final goal can be reached only through a series of critical outcome at each phase. In particular, recognizing as core infrastructures various online/offline channels, deep trust, and rich communications is an important finding for a successful relationship management. Also, related literatures suggest the following key factors to be influential in more that two phases: professionalism including expertise, similarity, channel capacity. Based on these findings, future efforts need to be put on the research & development of related measurement and management tools. We do hope more people dance with their partners through these efforts.

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데이터 트래픽에서의 Self-Similar 특성 (Self-Similarity Characteristic in Data traffic)

  • 김창호;황인수;최삼길;김동일;이동철;박기식
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 1999년도 춘계종합학술대회
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    • pp.146-151
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    • 1999
  • 기존의 큐잉 분석은 네트워크 용량설계 및 성능 예측을 할 때 상당히 유용하지만, 대부분의 실제 경우에서 큐잉 분석으로부터 예측된 결과는 실제 관측된 성능과는 상당히 다르다. 특히, 최근 몇 년 동안 몇몇 환경에서 트래픽 패턴이 Poisson 패턴보다는 차라리 Self-similar 패턴에 더 가깝다는 것이 입증되어 왔다. 본 논문에서는 이러한 Self-similar 확률과정의 정의 및 트래픽의 특성, 그리고 최근 논문들에서 보고된 사례에 대해서 고찰해 봄으로써, 실제의 데이터 트래픽 특성에 대해 더 나은 이해를 제공하고자 한다.

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동영상 복사본 검출을 위한 MPEG-7 Video Signature 성능분석 (Analyzing Performance of MPEG-7 Video Signature for Video Copy Detection)

  • 유정수;류재석;낭종호
    • 정보과학회 컴퓨팅의 실제 논문지
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    • 제20권11호
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    • pp.586-591
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    • 2014
  • 최근 언제 어디서든 동영상 컨텐츠에 접근할 수 있게 됨으로써 배포된 영상은 쉽게 복사되고, 변형되고 재배포 되어 저작권 보호에 취약하다는 문제점을 내포하고 있다. 따라서 비디오 복사본의 유사도를 검출하고 측정하는 방법들이 요구되어진다. 본 논문에서는 복사본 검출 기술 중 MPEG에서 표준화 한 MPEG-7 Video Signature를 이용하여 다양한 변화를 갖는 동영상에서의 다양한 분별력 분석을 하였다. MPEG-7 Video Signature는 블록기반의 추상화 방식이므로 동영상의 영역 변화에 대해서 취약할 것이라고 가정하고 실험하였다. 분석한 결과 실제로 영역변화에 대해서 일반적으로 일어날 수 있는 강도에서도 매우 취약함을 볼 수 있었다.

모델 기반 이동 물체 추적 알고리즘 (Model-Based Moving Object Tracking Algorithm)

  • 김태식;김윤호;이명길;전춘;이주신
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2000년도 춘계종합학술대회
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    • pp.356-359
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    • 2000
  • 본 논문에서는 움직이는 배경에서 이동물체를 추적하는 모델 기반 이동물체 추적 알고리즘을 제안한다. 제안한 알고리즘은 물체의 이동시 발생하는 형태 변화에 적응하기 위하여 영상 사이의 유사도 이용과 Hausdorff 거리 모델을 사용하였으며, 이동 물체의 위치 탐색 시간을 줄이기 위하여 2D-Logarithmic 탐색 기법을 사용하였다. 도로에 운행중인 모터사이클을 실험영상으로 하였으며 실험 결과 실제 위치와 추적 결과에 대한 평균자승 오차는 1.845로써 비교적 우수한 추적 정합 결과를 얻었다.

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예안(禮安) 군자리(君子里)의 후조당(後彫堂) 연구(硏究) (A Study on Hoojo-dang in Gunja-ri, Yeaan)

  • 서치상
    • 건축역사연구
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    • 제11권4호
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    • pp.21-34
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    • 2002
  • Hoojo-dang is the Beol-dang of Gwangsan Kim's family in Gunja-ri, Yeaan This study aims to reconstruct the architectural drawings of the building through actual measurement, and by investigating documentary records of Kim's family, to trace and infer when the building was originally constructed. In doing this, it enables to identify and describe the architectural types and characteristics. The results are as follows, 1) Hoojo-dang was established in 1567 by Kim Bu-pil(1516-1577). From the beginning, Hoojo-dang, Byeol-myo(family shrine) and Ju-sa(shrine kitchen) were situated in the separate area from An-chae(main building). Later the Ik-rang(additional transept part) of Hoojo-dang was added to its main body as a room for entertainment. 2) The types of floor plan and windows of Hoojo-dang are similar to those of the lecture halls of Dosan-seowon, Sosu-seowon and Yeaan-hyangyo nearby. The main reason for the similarity of floor plan and window types in those buildings is that the students of the great Korean Confucian, Lee Hwang in 16th, managed and controlled those constructions. 3) The separate area composed of Hoojo-dang, Byeol-myo and Ju-sa was mainly designed for satisfying Confucian ceremonial principles. In addition, there are lifting doors designed for elevating the spatial flexibility.

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다중 파라메터를 이용한 동적 수축시 허리 근육 피로 측정에 관한 연구 (A Study on the Measurement of Back Muscle Fatigue During Dynamic Contraction Using Multiple Parameters)

  • 윤중근;정철기;여송필;김성환
    • 대한전기학회논문지:시스템및제어부문D
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    • 제55권7호
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    • pp.344-351
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    • 2006
  • The fatigue of back muscle in the repetitive lifting motion was studied using multiple parameters(FFT_MDF, RMS, 2C, NT) in this study. Recent developments in the time-frequency analysis procedures to compute the IMDF(instantaneous median frequency) were utilized to overcome the nonstationarity of EMG signal using Cohen-Posch distribution. But the above method has a lot of computation time because of its complexity. So, in this study, FFT_MDF(median frequency estimation based on FFT) algorithm was used for median frequency estimation of back muscle EMG signal during muscle work in uniform velocity portion of lumbar movement. The analysis period of EMG signal was determined by using the run test and lumbar movement angle in dynamic task, such as lifting. Results showed that FFT_MDF algorithm is well suited for the estimation of back muscle fatigue from the view point of computation time. The negative slope of a regression line fitted to the median frequency values of back muscle EMG signal was taken as an indication of muscle fatigue. The slope of muscle fatigueness with FFT_MDF method shows the similarity of 77.8% comparing with CP_MDF(median frequency estimation based on Cohen Posch distribution) method.