• 제목/요약/키워드: Norm

검색결과 2,278건 처리시간 0.029초

고차원 공간에서 유클리드 거리의 효과적인 근사 방안 (An Effective Method for Approximating the Euclidean Distance in High-Dimensional Space)

  • 정승도;김상욱;김기동;최병욱
    • 전자공학회논문지CI
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    • 제42권5호
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    • pp.69-78
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    • 2005
  • 고차원 공간상의 벡터들 간의 유클리드 거리를 빠르게 계산하는 것은 멀티미디어 정보 검색을 위하여 매우 중요하다. 본 논문에서는 고차원 공간상의 두 벡터들 간의 유클리드 거리를 효과적으로 근사하는 방법을 제안한다. 이러한 근사를 위하여 두 벡터들의 놈(norm)을 사용하는 방법이 기존에 제안된 바 있다. 그러나 기존의 방법은 두 벡터간의 각도 성분을 무시하므로 근사 오차가 매우 커지는 문제점을 가진다. 본 연구에서 제안하는 방법은 기준 벡터라 부르는 별도의 벡터를 이용하여 추정된 두 벡터간의 각도 성분을 그들을 위한 유클리드 거리 근사에 사용한다. 이 결과, 각도 성분을 무시하는 기존의 방법과 비교하여 근사 오차를 크게 줄일 수 있다. 또한, 제안된 방법에 의한 근사 값은 유클리드 거리 보다 항상 작다는 것을 이론적으로 증명하였다. 이는 제안된 방법을 이용하여 멀티미디어 정보 검색을 수행할 때 착오 기각이 발생하지 않음을 의미하는 것이다. 다양한 실험에 의한 성능 평가를 통하여 제안하는 방법의 우수성을 규명한다.

지역사회 사회자본 척도 개발을 위한 질적연구 - 지역사회복지네트워크를 중심으로 - (The Qualitative Study on the Development of Social Capital Scale in Community - Focused on Community Welfare Network -)

  • 최종혁;안태숙;이은희
    • 한국사회복지학
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    • 제62권4호
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    • pp.297-324
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    • 2010
  • 본 연구는 최근 우리나라에서 다양한 형태로 펼쳐지고 있는 지역사회복지네트워크를 대상으로 한국적 특성에 맞는 사회자본 척도를 개발하는데 있다. 이를 위해 문헌연구와 심층인터뷰를 통한 질적 분석으로 신뢰, 규범, 네트워크와 관련된 개념들을 도출하였다. 도출한 개념은 양적 측정지표 문항으로 전환, 선행 사회자본 측정지표와의 비교분석, 전문가집단의 문항내용 검토와 예비조사를 통해 총 90개의 예비문항으로 개발되었다. 본조사를 통해 최종적으로 확정된 지표는 총 79개 문항으로 신뢰 30개, 규범 22개, 네트워크 27개로 구성되었다. 각 영역에 대한 Cronbach's Alpha 값은 신뢰 .948, 규범 .899, 네트워크 .906으로 높은 신뢰도를 나타냈다. 또한 탐색적 요인분석에 의해 추출된 요인들과 질적연구에서 도출된 신뢰, 규범, 네트워크 영역별 범주와의 연결에 있어서도 양호하게 연결되었다. 본 연구에서 개발된 지역사회 사회자본 척도는 지역사회복지네트워크의 운영 실태에 대한 객관적 파악 및 이를 통해 지역사회복지네트워크의 활성화를 위한 효율적인 방안마련이 가능할 것으로 본다.

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현대패션에 나타난 스웨그(swag)룩 (The Swag Look in Modern Fashion)

  • 이정호;이진민
    • 복식
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    • 제66권4호
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    • pp.94-110
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    • 2016
  • The purpose of this study is to delve into the identity of the swag style which has diversified into various forms by exploring the phenomenon, formative characteristics and the internal values of the swag style in modern fashioin. This study discusses the concept and the socio-cultural meanings of swag from the perspective of Jean Baudrillard's hyper-reality, and a form of existence. The classifies the swag fashion styles into parody, hip hop and collage-type mix-and-match. Expressive characteristics of the swag look in modern fashion are as follows. First, the swag look utilizes the parody technique. In the mid-2000s, the look parodied brand logos as a form of self-mocking and active self-derision toward cheap imitations. Second, the swag look borrows from the expressive factors of the hip-hop style. Born as a sub-culture based on music, hip-hop has become a way of life, as its nature became multi-cultural and trans-cultural while its fashion style gained popularity globally after the 1980s. Third, the swag look barrows from the pop-type collage form as it mixes-and-matches costume items based on the expressive characteristics of hip hop, and this can be seen through items being used in new, non-formative and free styles. Comic aesthetics is revealed in parodied expression, hip-hop factors and collage-style mix-and-match. Swag as a hyper-reality manifests itself in various natures: humorous nature, negative nature and deconstructive nature through reflection and re-enactment of reality, transmutation and distortion of reality, and absence of reality respectively. However, it does not have a binding nature, which is the norm for subcultures. This characteristic, in combination with it having internal lightness, strong meaning of communication, and a sharing of self-contentment, distinguishes itself from the general meanings of existing parody fashion, hip-hop fashion and collage fashion.

Optimal Placement of Sensors and Actuators Using Measures of Modal Controllability and Observability in a Balanced Coordinate

  • Park, Un-Sik;Choi, Jae-Weon;Yoo, Wan-Suk;Lee, Man-Hyung;Son, Kwon;Lee, Jang-Myung;Lee, Min-Cheol;Han, Sung-Hyun
    • Journal of Mechanical Science and Technology
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    • 제17권1호
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    • pp.11-22
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    • 2003
  • In this paper, a method for optimal placement of sensors and actuators is presented by using new measures of modal controllability and observability defined in a balanced coordinate system. The proposed new measures are shown to have a great advantage in practical use when they are used as criteria for selecting the locations of sensors and actuators, since the most controllable and observable locations can be obtained to be identical. In addition, they are more accurate than the measures of Hamdan and Nayfeh in that the effects of the eigenvector norm are considered into the magnitude of measures. In simulations, to verify the effectiveness of the proposed measures and optimal placement method, the closed-loop response of a simply supported flexible beam, in which the number and locations of actuators are determined by using the proposed measures and optimal placement method, has been examined and compared with the case of Hamdan and Nayfeh’s measures.

The Feasibility of Event-Related Functional Magnetic Resonance Imaging of Power Hand Grip Task for Studying the Motor System in Normal Volunteers; Comparison with Finger Tapping Task

  • Song, In-Chan;Chang, Kee-Hyun;Han, Moon-Hee
    • 대한자기공명의과학회:학술대회논문집
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    • 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
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    • pp.111-111
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    • 2001
  • 목적: To evaluate the feasibility of the event-related functional MR study using power grip studying the hand motor system 대상 및 방법: Event-related functional MRI was performed on a 1.5T MR unit in seven norm volunteers (man=7, right-handedness=2, left-handedness=5, mean age: 25 years). A single-shot GRE-EPI sequence (TR/TE/flip angle: 1000ms/40ms/90, FOV = 240 mm matrix= 64$\times$64, slice thickness/gap = 5mm/0mm, 7 true axial slices) was used for functiona MR images. A flow-sensitive conventional gradient echo sequence (TR/TE/flip angl 50ms/4ms/60) was used for high-resolution anatomical images. To minimize the gross hea motion, neck-holders (MJ-200, USA) were used. A series of MR images were obtained in axial planes covering motor areas. To exclude motion-corrupted images, all MR images wer surveyed in a movie procedure and evaluated using the estimation of center of mass of ima signal intensities. Power grip task consisted of the powerful grip of all right fingers and hand movement ta used very fast right finger tapping at a speed of 3 per 1 second. All tasks were visual-guid by LCD projector (SHARP, Japan). Two tasks consisted of 134 phases including 7 activatio and 8 rest periods. Active stimulations were performed during 2 seconds and rest period were 15 seconds and total scan time per one task was 2 min 14 sec. Statistical maps we obtained using cross-correlation method. Reference vector was time-shifted by 4 seconds an Gaussian convolution with a FWHM of 4 seconds was applied to it. The threshold in p val for the activation sites was set to be 0.001. All mapping procedures were peformed usin homemade program an IDL (Research Systems Inc., USA) platform. We evaluated the activation patterns of the motor system of power grip compared to hand movement in t event-related functional MRI.

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조선후기 풍속화에 나타난 치마.저고리에 관한 연구 (A Study on Chima and Jeogori for Women appeared in Genre Pciture of Late Chosun Dynasty)

  • 심화진
    • 복식
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    • 제50권2호
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    • pp.125-140
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    • 2000
  • The major findings of basic women wear in genre painting were ; 1. Due to the influence of Shill-Hak (practical science) philosophy, Jeogori became shorter and a tighter fit came to be the norm. 2,. The shortening of the Jeogori influenced a longer Chima with a wider span providing comfort in movement or at work. The end of the skirt was often held by one hand to the waist adding to comfort. This was called the Go-dul-chima(Lifted Chima). 3. Because the Geo-dul-chima exposed a portion of one underwear at the bottom of the dress this influenced the "irnamentation' of underpants and underskits. 4. Collars or lapels came in the form of Dang-ko, Kal, Mok-pan and Ban-Mokpan. Among there Dang-ko style collars were the most common which allows us to conclude that this was the most popular. 5. The most commonly used colors for Jeogori were white (39.8%) and jade(18.3%) . The most commonly used colors for CHima were deep blue(34.4%) and jade(20.4%) . The lower Chima used the darkercolors to give stability to the overall costume. 6. Clothing had the function of differentiating the classes. Only the Yang-ban were allowed to wear the Samhijang Jeogori and the Gob-Chima(double layered Chima) and the knotting of the Chima to the left. But the painting show that these rules were not adhered to in the strictest manner. With the bases of these types of chima and Jeogori can look at the characteristical beauty of the ordinary women during the late Cho-sun dynasty. First is the beauty which comes from mystery of those parts of body which can not be seen. A sense of subtle and sensual beauty as well as that coming from the enlargement of reduction of the upper body, narrow waist and abundant lower body parts creating an ideal silhouette of sexual charm. An expression of emotion through clothing by those who lived during those times.

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정상 성인에서 체간 굴근, 신근의 근력과 요추 전만각의 상관관계에 관한 연구 (A Study on Correlation between Power of Trunk Flexors, Extensors and Lumbar Lordotic Angle in Normal Adults)

  • 최보미;이정민;김현수
    • 척추신경추나의학회지
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    • 제7권2호
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    • pp.39-52
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    • 2012
  • Objectives : The purpose of this study was to investigate the correlation between lumbar lordotic angle and the power of trunk flexors, extensors in normal adults Methods : 34 normal participants participated in this study. Their lumbar lordotic angle(L1-S1 Cobb's angle and L1-L5 cobb's angle) was measured by x-ray taken on lateral direction, erect cross-arm position. And muscle power of trunk flexors and extensors of each participant measured using Cybex HUMAC NORM. Results : 1. The average of L1-S1 Cobb's angle was $47.21{\pm}8.88^{\circ}$ and the average of L1-L5 Cobb's angle was $36.32{\pm}9.62^{\circ}$(Table IV). 2. The average ratio of trunk flexors/extensors was $6.44{\pm}19.31%$(Table V). The average power of the trunk flexors was $165.18{\pm}55.05$(Newton-Meter/kg), and the power of trunk extensors was $257.18{\pm}85.53$ (Newton-Meter/kg)(Table VI). 3. Lumbar lordotic angle has no relation to the ratio of trunk flexors/extensors(Table VII, Fig. 4). 4. Lumbar lordotic angle has no relation to both the power of the trunk flexors and extensors(Table VIII, Fig. 5, Fig. 6). Conclusions : These results suggest that the lumbar lordotic angle measured by radiograph could not evaluate the power and ratio of trunk flexors, extensors.

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치매노인을 부양하는 여성의 건강관련 삶의 질 (Health-Related Quality of Life among Women Caregivers of Older Adults with Dementia)

  • 김명수;김동희;김정순;박경연;박남희
    • 성인간호학회지
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    • 제19권1호
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    • pp.24-34
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    • 2007
  • Purpose: The objective of this study was to define the predictors of health related quality of life(HRQoL) of women caregivers of the demented elderly patients. Methods: The subjects of this study were 140 pairs of patients with dementia and their caregivers. The characteristics of dementia patients and caregivers, Barthel index and SF-36 were measured in this study. T-test, ANOVA, Pearson correlation coefficient, and stepwise multiple regression were used for data analysis. Results: The health related quality of life(HRQoL) score of women caregivers was $288.35{\pm}66.10$ for norm based scoring. HRQoL of women caregivers was correlated with patients' ADL, severity of dementia, caregivers' age, burden, and family support. The major factors that affected the physical components of women caregivers of patients with dementia was the age of the caregiver, burden, and ADL which explained 36.0% of HRQoL. The main predictors of women caregivers' emotional state was the caregiver's burden. Conclusion: Patients' support systems must be implemented to improve the physical HRQoL of caregivers. A caregivers' burden relief program needs to be prepared to increase their emotional HRQoL and further studies and efforts will be needed to evaluate those effects.

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Chirp 신호를 이용한 해저퇴적층의 음향학적 특성 역산 (Inversion of Acoustical Properties of Sedimentary Layers from Chirp Sonar Signals)

  • 박철수;성우제
    • 한국음향학회지
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    • 제18권8호
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    • pp.32-41
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    • 1999
  • 본 논문은 chirp신호와 두 개의 근거리 청음기를 이용한 해저퇴적층의 음향학적 특성치 역산기법을 제시한다. 역산문제를 확률론적 모델로 정식화하고, 역산의 해를 역산인자의 a priori분포와 유사도함수의 곱으로 표현되는a posteriori 확률분포로 정의하였다. 퇴적층의 음속과 층두께의 a priori정보를 파형 매칭 기법으로 추정한 후 다수의 퇴적층이 존재하는 환경모델을 부분퇴적층모델로 치환하고, 계측신호와 모의신호의 L₂노음을 이용하여 정의된 목적함수에 대해 반복적인 유전자알고리즘 탐색을 수행하여 탐색공간의 축소로 인한 탐색효율과 결과의 향상을 얻었다. A posteriori 확률분포의 다중적분의 형태로 정의되는 인자의 주변확률분포와 평균의 추정은 유전자알고리즘의 탐색과정에서 선택된 탐색점들을 이용하여 수행되었다. 제시된 역산기법의 검증을 위해 두 가지 퇴적층 환경모델을 설정하고 잡음을 첨가한 합성신호에 대해 역산기법을 적용하여 역산해를 추정하였고 역산결과로부터 본 역산기법의 유용성을 확인하였다.

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고장 특이시스템의 신뢰 $H_\infty$ 제어기 설계 알고리듬 개발 (Development of reliable $H_\infty$ controller design algorithm for singular systems with failures)

  • 김종해
    • 전자공학회논문지SC
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    • 제41권4호
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    • pp.29-37
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    • 2004
  • 본 논문에서는 구동기 고장을 가지는 시간지연 특이시스템의 신뢰 H/sub ∞/ 상태궤환 제어기 설계방법을 제안한다. 미리 설정한 영역내에서의 구동기 고장이 발생함에도 불구하고 특이시스템의 점근적 안정성(asymptotic stability)과 H/sub ∞/ 성능지수를 만족하는 신뢰 H/sub ∞/ 제어기가 존재할 조건과 제어기 설계 기법을 선형행렬부등식, 특이값 분해(singular value decomposition), 슈어 여수정리(Schur complements), 변수 치환 등에 의하여 제시한다. 제안한 충분조건은 구하려는 모든 변수의 견지에서 하나의 선형행렬부등식으로 표현되기 때문에 모든 해를 동시에 구할 수 있다는 장점이 있다. 또한, 제안한 알고리듬을 이용하면 변수불확실성과 시간지연을 가지는 특이시스템에 대한 강인 신뢰(robust reliable) H/sub ∞/ 제어기 설계문제에도 쉽게 확장됨을 보인다. 마지막으로, 제안한 알고리듬의 타당성을 수치예제를 통하여 확인한다.