• 제목/요약/키워드: variance structure

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GOP를 구성하는 프레임들의 순서 변경을 이용한 효율적인 스무딩 알고리즘 (An Efficient Smoothing Algorithm Using the Change of Frame Sequence in GOP)

  • 이면재
    • 한국게임학회 논문지
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    • 제6권2호
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    • pp.51-60
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    • 2006
  • 스무딩은 가변 비트율로 저장된 비디오 데이터를 클라이언트로 전송할 때 일련의 고정 비트율로 전송할 수 있도록 전송 계획을 세우는 것으로 이러한 스무딩 알고리즘에는 CBA, MCBA, MVBA, PCRTT 등이 있다. 그러나 이 알고리즘들에서는 GOP내에서 프레임들간의 바이트 수의 차이가 심한 경우에도 이 순서대로 전송 계획을 세우기 때문에 불필요하게 전송률이 변화되거나 급격하게 높은 전송률이 요구될 수 있다. 이는 네트워크 자원의 효율적 인 사용을 어렵게 할 수 있다. 이를 개선하기 위하여 본 논문에서는 빠른 시간안에 최적의 해를 찾을 수 있는 백트랙킹 방법을 이용하여 GOP 내에서 가장 완만하게 프레임의 바이트 수가 변화되는 프레임들의 순서를 검색하여 이 순서대로 전송 계획을 세우는 스무딩 알고리즘과 이를 위한 구조를 제안한다. 제안 알고리즘의 성능은 다양한 비디오 소스를 가지고 MVBA 알고리즘과 전송률 변화 횟수, 첨두 전송률, 전송률 변화량을 비교 분석하여 평가한다.

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리버스 무단 댐퍼용 연속가변밸브의 튜닝 파라미터에 관한 연구 (A Study on the Tuning Parameter of Continuous Variable Valve for Reverse Continuous Damper)

  • 윤영환;최명진;유송민
    • 한국자동차공학회논문집
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    • 제10권3호
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    • pp.192-200
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    • 2002
  • Semi-active suspension systems are greatly expected to be in the mainstream of future controlled suspensions for passenger cars. In this study, a continuous variable damper for a passenger car suspension is developed, which is controlled actively and exhibits high performance with light weight, low cost, and low energy consumption. To get fast response of the damper, reverse damping mechanism is adapted, and to get small pressure change rate after blow-off, a pilot controlled proportional valve is designed and analyzed. The reverse continuous variable damper is designed as a HS-SH damper that offers good body control with reduced transferred input force from tire, compared with any other type of suspension system. The damper structure is designed, so that rebound and compression damping force can be tuned independently, of which variable valve is placed externally. The rate of pressure change with respect to the flow rate after blow-off becomes smooth when the fixed orifice size increases, which means that the blow-off slope is controllable using the fixed orifice size. The damping force variance is wide and continuous, and is controlled by the spool opening, of which scheme is usually adapted in proportional valves. The reverse continuous variable damper developed in this study is expected to be utilized in the semi-active suspension systems in passenger cars after its performance and simplicity of the design is confirmed through real car test.

화장품 플래그십 스토어의 브랜드 아이덴티티와 브랜드 인지도의 영향관계에 관한 연구 (A Study on the Effect of Brand Identity of Cosmetic Flagship Stores on Brand Awareness)

  • 양미선;이주형;박찬일
    • 한국실내디자인학회논문집
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    • 제26권2호
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    • pp.45-54
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    • 2017
  • Recently, cosmetic shops play important roles in effectively delivering brand identity to customers. As a most effective mean to deliver brand identity to customers, a shop becomes the space to sell and buy brand image. This study divides brand identity into external identity as a space and internal identity as a brand philosophy with analysis of brand identity structure. To do this, the study proposition that brand awareness is high when there is high conformity between brand identities and survey to five Korean domestic cosmetic manufacturers that have a flagship store has been conducted to prove the proposition. With oneway Analysis of Variance on the survey, the result that the conformity between group's brand identities has significant relationship with brand awareness has been drawn. The findings are as followings; The spatial expression elements that have the strongest effects on the conformity between brand identities are facade, logo and sign, spatial image, fixtures image, symbolic sculpture and programs in order. For spatial elements, colors, shapes and materials have effects on conformity between brand identities in order. With analysis of spatial elements and their colors, shapes and materials, it is shown that all brand colors are used. In addition, brand conformity is emphasized with shapes and materials as well as colors. Futhermore, the brand awareness is improved when emphasis with such spatial elements is repeated in continuous manner. Also, the higher brand identity got, the higher brand awareness went up.

QTL Analysis of Teat Number Traits in an F2 Intercross between Landrace And Korean Native Pigs

  • Park, Hee-Bok;Han, Sang-Hyun;Yoo, Chae-Kyoung;Lee, Jae-Bong;Cho, Sang-Rae;Cho, In-Cheol
    • 한국수정란이식학회지
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    • 제31권4호
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    • pp.313-318
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    • 2016
  • The aim of this study was to identify quantitative trait loci (QTLs) influencing teat number traits in an $F_2$ intercross between Landrace and Korean native pigs (KNP). Three teat number traits (left;right;and total) were measured in 1105 $F_2$ progeny. All experimental animals were genotyped with 173 informative microsatellite markers located throughout the pig genome. We detect that seven chromosomes harbored QTLs for teat number traits: genome regions on SSC1;3;7;8;10;11;and 13. Six of fourteen identified QTL reached genome-wide significance. In SSC7;we identified a major QTL affecting total teat number that accounted for 5.6 % of the phenotypic variance;which was the highest test statistic (F-ratio = 61.1 under the additive model;nominal $P=1.3{\times}10^{-14}$) observed in this study. In this region;QTL for left and right teat number were also detected with genome-wide significance. With exception of the QTL in SSC10;the allele from KNP in all 6 identified QTLs was associated with decreased phenotypic values. In conclusion;our study identified both previously reported and novel QTL affecting teat number traits. These results can play an important role in determining the genetic structure underlying the variation of teat number in pigs.

한국형진단명기준환자군 분류체계의 동질성 평가 (Evaluation of the Homogeneity of Korean Diagnosis Related Groups)

  • 김형선;이선희;남정모
    • 보건행정학회지
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    • 제23권1호
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    • pp.44-51
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    • 2013
  • Background: This study designed to evaluate the homogeneity of Korean diagnosis related group (KDRG) version 3.4 classification system. Methods: The total 5,921,873 claims data submitted to the Health Insurance Review and Assessment Service during 2010 were used. Both coefficient of variation (CV) and reduction in variance of cost were measured for evaluation. This analysis was divided into before and after trimming outliers at the level of adjacent DRG (ADRG), aged ADRG (AADRG) split by age, and DRG split by complication and comorbidity. Results: At the each three level of ADRG, AADRG, and DRG, there were 38.9%, 38.7%, and 30.0% of which had a CV > 100% in the untrimmed data and there were 1.4%, 1.4%, and 1.9% in the trimmed one. Before trimming outliers, ADRGs explained 52.5% of the variability in resource use, AADRGs did 53.1% and DRGs did 57.1%. The additional explanatory power by age and comorbidity and complication (CC) split were 0.6%p and 4.6%p for each, which were statistically significant. After trimming outliers, ADRGs explained 75.2% of the variability in resource use, AADRGs did 75.6%, and DRGs did 77.1%. The additional explanatory power were 0.4%p and 2.0%p for each, which were statistically significant too. Conclusion: The results demonstrated that KDRG showed high homogeneity within groups and performance after trimming outliers. But there were DRGs CV > 100% after age or CC split and the most contributing factor to high performance of KDRG was the ADRG rather than age or CC split. Therefore, it is recommended that the efforts for improving clinical homogeneity of KDRG such as review of the hierarchical structure of classification systems and classification variables.

다변량 통계 분석기법을 이용한 한강수계 지천의 수질 평가 (Evaluation of Water Quality for the Han River Tributaries Using Multivariate Analysis)

  • 김요용;이시진
    • 대한환경공학회지
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    • 제33권7호
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    • pp.501-510
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    • 2011
  • 한강의 주요 14개 지류하천 유역의 수질오염원을 평가하고, 2007. 1~2009. 12의 하천 수질자료(14 data set)로 SPSS-17.0을 이용하여 하천별 수질 특성을 평가하였다. 시 공간변화에 대한 군집 분석을 실시한 결과 공간변화에 따라 4그룹으로 평가되었으며, 유역의 오염원 종류 및 밀도가 군집분류에 가장 큰 영향을 미치는 것으로 나타났다. 시간변화에 따라 여름에서 가을까지(7~10월)와 겨울에서 초여름까지(11~6월)의 2그룹으로 분류되어 강우와 기온 그리고 부영양화 현상이 군집화에 기여하는 것으로 평가되었다. 조사대상 하천의 수질오염 요인은 유기물질 영양염류 세균오염요인과 하천 내 물질대사요인으로(71~90%) 설명되었고, 계절에 따라 주요인(수질오염물질)은 변화하는 것으로 나타났다. 각 하천의 수질특성은 요인과 유역 오염원을 같이 평가하였을 때 유용한 결과를 얻을 수 있었다.

MedisGroups를 이용한 관상동맥우회술의 중증도 보정사망률에 관한 연구 (Severity-Adjusted Mortality Rates of Coronary Artery Bypass Graft Surgery Using MedisGroups)

  • 권영대
    • 한국의료질향상학회지
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    • 제7권2호
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    • pp.218-228
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    • 2000
  • Background : Among 'structure', 'process' and 'outcome' approaches, outcome evaluation is considered as the most direct and best approach to assess the quality of health care providers. Risk-adjustment is an essential method to compare outcome across providers. This study has aims to judge performance of hospitals by severity adjusted mortality rates of coronary artery bypass graft (CABG) surgery. Methods : Medical records of 584 patients who got the CABG surgery in 6 general hospitals during 1996 and 1997 were reviewed by trained nurses. The MedisGroups was used to quantify severity of patients. The predictive probability of death was calculated for each patient in the sample from a multivariate logistic regression model including the severity score, age and sex. For evaluation of hospital performance, we calculated ratio of observed number to expected number of deaths and z score [(observed number of deaths - expected number of deaths)/square root of the variance in the number of deaths], and compared observed mortality rate with confidence interval of adjusted mortality rate for each hospital. Results : The overall in-hospital mortality was 7.0%, ranged from 2.7% to 15.7% by hospital. After severity adjustment the mortality by hospital was from 2.7% to 10.7%. One hospital with poor performance was distinctly divided from others with good performance. Conclusion : In conclusion, severity-adjusted mortality rate of CABG surgery might be applied as an indicator for hospital performance evaluation in Korea. But more pilot studies and improvement of methodologies has to be done to use it as quality indicator.

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통계적 채널 Quality 정보를 이용한 직교 주파수분할 다중접속(OFDMA) Part-I: 시스템 및 채널 모델링 (Orthogonal Frequency Division Multiple Access with Statistical Channel Quality Measurements Part-I: System and Channel Modeling)

  • 윤석현
    • 한국통신학회논문지
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    • 제31권2A호
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    • pp.119-127
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    • 2006
  • Part-I과 II를 포함하는 본 연구에서는 하향링크 직교 주파수분할 다중접속(OFDMA) 방식을 위한 실제적인 동적 채널할당 방법에 대해 논의한다. OFDMA 시스템은 채널의 상태정보 궤환을 위한 상향링크에서의 오버헤드를 줄이기 위해 부반송파들의 집합을 하나의 부채널로 정의하고 이를 채널의 상태정보 궤환, 사용자 다중화 및 전력/부호화율 할당의 단위로 사용하는데 본 논문(part-I)에서는 부채널의 일반화된 형태로 연속구조와 분산구조를 정의하고 이들 각 부채널구조의 통계적 특성을 살펴본다. 특히, 각 구조에 대해 부채널상에서의 신호대 잡음비(SNR) 분포를 라이스 분포로 모델링함으로써 각 부채널의 채널 상태를 채널이득의 순시 평균 및 분산의 1, 2차 모멘트로 나타내고 주어진 다중경로 채널 모델에 대해 이 두 파라미터 값의 확률 분포를 유도한다. 본 논문의 결과는 part-II에서 라이스 모델링에 기초한 일반화된 동적자원할당 알고리즘을 제시하고 성능분석을 수행하는데 사용된다.

웨이블릿 영역에서 훈련 없는 은닉 마코프 트리 모델을 이용한 영상 보간 (Image Interpolation Using Hidden Markov Tree Model Without Training in Wavelet Domain)

  • 우동헌;엄일규;김유신
    • 대한전자공학회논문지SP
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    • 제41권4호
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    • pp.31-37
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    • 2004
  • 웨이블릿 변환은 영상을 분석하고 처리하는데 유용한 도구로써 영상 압축, 영상 잡음 제거 등의 분야에서 우수한 성능을 보여주었다. 웨이블릿 계수들은 은닉 마코프 트리(Hidden Markov Tree: HMT) 모델에 의해 효과적으로 모델링 될 수 있다. 그러나 영상 보간에서 은닉 마코프 트리 모델을 적용하기 위해서는 훈련 과정이 필요하며 훈련 과정에서 획득된 파라미터들이 입력 영상과 잘 맞지 않는 단점이 있다. 본 논문에서는 웨이블릿 영역에서 영상 보간을 위해 은닉 마코프 트리의 구조를 사용하되, 그 파라미터들은 훈련 과정 없이 부대역간의 통계적 특성을 이용하여 직접 추정한다. 제안 방법에서 웨이블릿 계수는 가우스 혼합 모델(Gauss Mixture Model: GMM)로 모델링 된다. 가우스 혼합 모델의 상태 천이 확률은 부대역간의 웨이블릿 계수의 통계적 천이 특성을 이용하여 결정하며, 각 상태의 분산은 웨이블릿 계수의 지수적 감소(exponential decay) 특성에 의해, 추정된다. 모의실험에서 제안 방법은 전통적인 bicubic 방법이나 훈련 과정을 필요로 하는 은닉 마코프 모델을 사용한 방법보다 여러 테스트 영상들에 대해서 개선된 성능을 보여주었다.

Reliability and Validity of the Malay Version of the Breast-Impact of Treatment Scale (MVBITS) in Breast Cancer Women undergoing Chemotherapy

  • Zainal, Nor Zuraida;Shuib, Norley;Bustam, Anita Zarina;Sabki, Zuraida Ahmad;Guan, Ng Chong
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권1호
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    • pp.463-468
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    • 2013
  • Background: Body image dissatisfaction among breast cancer survivors has been associated with psychological stress resultant from breast cancer and resultant surgery. This study aimed to examine the psychometric properties of the Malay Version of the Breast-Impact of Treatment Scale (MVBITS) and to investigate the associations of retained factors with the Hospital Anxiety and Depression Scale (HADS) and the Rosenberg Self-Esteem Scale (RSES). Materials and Methods: The MVBITS was 'forward-backward' translated from English to Malay and then administered to 70 female breast cancer patients who came to the Oncology Clinic of University Malaya Medical Centre, Kuala Lumpur, Malaysia to undergo chemotherapy. Principal component analysis (PCA) with varimax rotation was performed to explore the factor structure of the MVBITS. Associations of retained factors were estimated with reference to Spearman correlation coefficients. Results: The internal consistency reliability of MVBITS was good (Cronbach's alpha 0.945) and showed temporal stability over a 3-week period. Principal component analysis suggested two factors termed as 'Intrusion' and 'Avoidance' domains. These factors explained 70.3% of the variance. Factor 1 comprised the effects of breast cancer treatment on the emotion and thought, while Factor 2 informed attempts to limit exposure of the body to self or others. The Factor 1 of MVBITS was positively correlated with total, depression and anxiety sub-scores of HADS. Factor 2 was positively correlated with total and anxiety sub-scores of HADS. MVBITS was also positively correlated with the RSES scores. Conclusions: The results showed that the Malay Version of Breast-Impact of Treatment Scale possesses satisfactory psychometric properties suggesting that this instrument is appropriate for assessment of body change stress among female breast cancer patients in Malaysia.