• Title/Summary/Keyword: variance structure

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

  • Lee, Myoun-Jae
    • Journal of Korea Game Society
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    • v.6 no.2
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    • pp.51-60
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    • 2006
  • Smoothing is a transmission plan where variable rate video data is converted to a constant bit rate stream. Among them are CBA, MCBA, MVBA, PCRTT and others. But, in these algorithm, a transmission plan is made in according to stored frame sequence in these algorithms. In case that the number of bytes in frames in GOP differs greatly each other, this may cause unnecessary transmission rate changes and may require high transmission rates abruptly when frame's byte is large. In result, it is difficult to use efficient network resource. In this paper, we proposed a smoothing algorithm that find the optimal frame sequence in short time by using backtracking method and smoothing's structure for the proposed smoothing algorithm. This algorithm decides the sequence of frames which requires the lowest variance of frame's bytes in GOP and make a transmission plan. In order to show the performance, we compared with MVBA algorithm by various evaluation factors such as the number of rate changes, peak rate, rate variability.

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

  • 윤영환;최명진;유송민
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.3
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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.

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

  • Yang, Mi-Seon;Lee, Ju-Hyeong;Park, Chan-Il
    • Korean Institute of Interior Design Journal
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    • v.26 no.2
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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
    • Journal of Embryo Transfer
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    • v.31 no.4
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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.

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

  • Kim, Hyung Seon;Lee, Sun Hee;Nam, Chung Mo
    • Health Policy and Management
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    • v.23 no.1
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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.

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

  • Kim, Yo-Yong;Lee, Si-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.7
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    • pp.501-510
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    • 2011
  • In this study, water pollution sources of 14 major tributaries of Han river and characteristics of water quality for each target streams were evaluated based on water quality data in 2007.1-2009.12 (14 data sets) using a statistical package, SPSS-17.0. Cluster analysis over time and space for each stream resulted in 4 groups for the spatial variations in which type and density of pollution sources in the basins showed the greatest impact on grouping. Moreover, cluster analysis for the time variation in which rainfall, temperature and eutrophication were shown to contribute to the clustering, produced 2 groups, from summer to fall (July-Oct.) and from winter to early summer (Nov.-June). Four factors were found as responsible for the data structure explaining 71-90% of the total variance of the data set depending on the streams and they were organic matter, nutrients, bacterial contamination. Factor analysis showed main factors (water pollutants) changed according to the season with different pattern for each stream. This study demonstrated that water quality of each stream could produce useful outcomes when factor and pollution source of basin were evaluated together.

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

  • Kwon, Young-Dae
    • Quality Improvement in Health Care
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    • v.7 no.2
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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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Orthogonal Frequency Division Multiple Access with Statistical Channel Quality Measurements Part-I: System and Channel Modeling (통계적 채널 Quality 정보를 이용한 직교 주파수분할 다중접속(OFDMA) Part-I: 시스템 및 채널 모델링)

  • Yoon, Seo-Khyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.2A
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    • pp.119-127
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    • 2006
  • In this two-part paper, we consider dynamic resource allocation in orthogonal frequency division multiple access(OFDMA). To reduce the reverse link overhead for channel quality information(CQI) feedback, a set of sub-carriers are tied up to a sub-channel to be used as the unit of CQI feedback, user-multiplexing and the corresponding power/rate allocation. Specifically, we focus on two sub-channel structures, either aggregated or distributed, where the SNR distribution over a sub-channel is modeled as Ricean in general, and the channel quality of a sub-channel is summarized as the mean and variance of channel gain envelop divided by noise standard deviation. Then, we develop a generalized two step channel/resource allocation algorithm, which uses the two statistical measurements, and analyze the spectral efficiency of the OFDMA system in terms of average frequency utilization. An extension to proportional fair algorithm will also be addressed. As confirmed by numerical results, the aggregated structure is preferred especially when intending aggressive link adaptation.

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

  • 우동헌;엄일규;김유신
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.4
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    • pp.31-37
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    • 2004
  • Wavelet transform is a useful tool for analysis and process of image. This showed good performance in image compression and noise reduction. Wavelet coefficients can be effectively modeled by hidden Markov tree(HMT) model. However, in application of HMT model to image interpolation, training procedure is needed. Moreover, the parameters obtained from training procedure do not match input image well. In this paper, the structure of HMT is used for image interpolation, and the parameters of HMT are obtained from statistical characteristics across wavelet subbands without training procedure. In the proposed method, wavelet coefficient is modeled as Gaussian mixture model(GMM). In GMM, state transition probabilities are determined from statistical transition characteristic of coefficient across subbands, and the variance of each state is estimated using the property of exponential decay of wavelet coefficient. In simulation, the proposed method shows improvement of performance compared with conventional bicubic method and the method using HMT model with training.

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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    • v.14 no.1
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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.