• 제목/요약/키워드: posterior performance

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Feature Voting for Object Localization via Density Ratio Estimation

  • Wang, Liantao;Deng, Dong;Chen, Chunlei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권12호
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    • pp.6009-6027
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    • 2019
  • Support vector machine (SVM) classifiers have been widely used for object detection. These methods usually locate the object by finding the region with maximal score in an image. With bag-of-features representation, the SVM score of an image region can be written as the sum of its inside feature-weights. As a result, the searching process can be executed efficiently by using strategies such as branch-and-bound. However, the feature-weight derived by optimizing region classification cannot really reveal the category knowledge of a feature-point, which could cause bad localization. In this paper, we represent a region in an image by a collection of local feature-points and determine the object by the region with the maximum posterior probability of belonging to the object class. Based on the Bayes' theorem and Naive-Bayes assumptions, the posterior probability is reformulated as the sum of feature-scores. The feature-score is manifested in the form of the logarithm of a probability ratio. Instead of estimating the numerator and denominator probabilities separately, we readily employ the density ratio estimation techniques directly, and overcome the above limitation. Experiments on a car dataset and PASCAL VOC 2007 dataset validated the effectiveness of our method compared to the baselines. In addition, the performance can be further improved by taking advantage of the recently developed deep convolutional neural network features.

비모수 베이지안 겉보기 무관 회귀모형 (A nonparametric Bayesian seemingly unrelated regression model)

  • 조성일;석인혜;최태련
    • 응용통계연구
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    • 제29권4호
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    • pp.627-641
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    • 2016
  • 본 논문에서는 겉보기 무관 회귀모형을 고려하고 디리크레 프로세스 혼합모형을 오차항의 분포로 하는 비모수 베이지안 방법을 제안한다. 제안된 모형을 바탕으로 사후분포를 유도하고 디리크레 프로세스 혼합모형의 붕괴깁스표집 방법을 통해 마코프 체인 몬테 칼로 알고리듬을 구성하고 사후추론을 실시한다. 모형의 성능을 비교하기 위해 모의실험을 실시하고, 더 나아가 한국지역의 강수량 예측에 대한 실제 자료에 적용해 본다.

Improvement in oral function after an oral exercise program including whole-body exercises

  • Seo, Su-Yeon;Choi, Yoon-Young;Lee, Kyeong-Hee;Jung, Eun-Seo
    • 한국치위생학회지
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    • 제21권1호
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    • pp.5-16
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    • 2021
  • Objectives: To evaluate the impact of an oral exercise program including whole-body exercises on oral function in older people. Methods: The participants (aged ≥65 years) were divided into three groups: intervention group I (only oral exercise), intervention group II (oral exercise with whole-body exercises), and control group (no intervention). The oral health status, saliva flow rate, and oral muscle strength were evaluated. Analyses were performed to compare the three groups and identify the changes in the aforementioned parameters before and after the program. Results: The saliva flow rate significantly increased in intervention groups I and II after the program. Oral muscle strength evaluation using the Iow a oral performance instrument showed that the anterior tongue strength increased significantly in intervention group I; the posterior tongue strength and cheek strength also increased but not significantly. The anterior tongue, posterior tongue, and cheek strengths significantly increased in intervention group II. Conclusions: The oral exercise program including whole-body exercises showed positive effects on the saliva flow rate and oral strength. No significant differences were observed in the quality of life related to oral health.

Analysis of the characteristics of mouthguards that affect isokinetic muscular ability and anaerobic power

  • Jung, Jae-Kwang;Chae, Woen-Sik;Lee, Kyu-Bok
    • The Journal of Advanced Prosthodontics
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    • 제5권4호
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    • pp.388-395
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    • 2013
  • PURPOSE. The purpose of this study was to estimate the effects of occlusal stability to identify action mechanisms of mouthguards, known to have a modulatory effect on limb muscle function. MATERIALS AND METHODS. This study included 20 male subjects to perform the isokinetic muscle tests and the Wingate anaerobic power test on both knee joints under five closed-mouth conditions: without or with 4 types of mouthguards with thickness of 2 mm based on premolar area: (1) full-coverage, (2) anterior partial-coverage, (3) right posterior partial-coverage, and (4) left posterior partial-coverage. The obtained results were subjected to One-way ANOVA with repeated measures, followed by post hoc test of the contrast method (${\alpha}$=.05). RESULTS. There was no significant difference between the closed position with and without a full-coverage mouthguard in all variables. However, significant differences were observed between with and without a partial-coverage mouthguard in muscular endurance during extension of the left knee, muscular power and endurance during flexion of the right knee. Additionally, significant differences were found between occlusal states with full- and partial-coverage mouthguards in muscular power and endurance during extension of the left knee. CONCLUSION. These findings indicate the elevation of vertical dimension by 2 mm or the inducement of occlusal stability had little effect on isokinetic muscle strength and anaerobic performance, while uneven distribution of occlusal force might have some positive effects.

Effects of an Ankle Foot Orthosis with Ankle Angles on Balance Performance in Healthy Adults

  • Kim, Chung-Sun;Park, Sang-Young
    • 대한인간공학회지
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    • 제30권2호
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    • pp.291-296
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    • 2011
  • This study was designed to investigate the effects of an ankle foot orthosis(AFO) with variable ankle joint angles on balance performance in healthy adults. Eighteen healthy adults were recruited in this repeated measures design with subjects as their own controls. An AFO with four kinds of ankle joint angles(-5, 0, 5, and 10 degree) were used and balance performance was measured during single limb standing. Three trials were obtained and then averaged for data analysis. Foot pressure was measured using an F-scan system and muscle activity was measured using an MP150 system. There were significant differences in balance performance with ankle joint angles. An AFO with -5 degrees was associated with significant increases in postural sway(anterior-posterior), and in muscle activity for the medial gastrocnemius and tibialis anterior compared with other degrees of angle. Findings of this study show that angles of an AFO are related to balance performance and a joint angle of 10 degree is effective for promoting joint stability and postural control. This information can be used by clinicians to prescribe AFOs.

미세투석법을 이용하여 흰쥐 후 사상하부에서 세포외액의 모노아민과 대사체들의 생체내 측정 (In Vivo Measurement of Extracellular Monoamines and Their Metabolites in the Rat Posterior Hypothalamus Using Microdialysis Technique)

  • 성기욱;김성윤;조영진;이권행;이상복
    • 대한약리학회지
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    • 제28권1호
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    • pp.1-9
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    • 1992
  • 최근에 개발된 생체내 미세투석법을 이용하여 정상혈압 흰쥐(WKY)와 자연발생성 고혈압 흰쥐(SHR)의 후 시상하부에서 세포외액의 모노아민과 그 대사체들을 측정하였다. 뇌정위 고정장치에 의해서 미세투석관을 후 시상하부에 위치시킨후 링거액으로 관류하였다. 모노아민과 그 대사체들은 고속액체 크로마토그라피와 전기화학 검출기를 이용하여 정량하였다. 미세투석관의 시험관내 회수율 검사 결과, 관류액의 유속과 신경화학물질의 상대적 회수율 사이에는 역비례 관계가 있음이 확인되었다. 정상 혈압 흰쥐에서 후 사상하부의 관류액으로 부터 축정한 각종 신경화학물질의 세포외액 농도는 도파민 32nM, 노르에피네프린 50nM, 에피네프린 50nM, 세로토닌 73nM, 3.4-dihydroxyphenylacetic acid(DOPAC) 281 nM, homovanillic acid(HVA) 181 nM, 5-hydroxyindoleacetic acid(5HIAA) 3767nM이었다. 후 시상하부에서 측정된 신경전달물질의 기준치는 WHY와 SHR사이에 차이가 없었으나, DOPAC, HVA, 5HIAA의 기준치는 WKY에 비해서 SHR에서 유의하게 높게 나타났다. 본 연구는 중추 신경화학물질들의 생체내 측정에 미세투석법을 이용할 수 있음을 보여주었다.

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Evolution Strategies Based Particle Filters for Nonlinear State Estimation

  • Uosaki, Katsuji;Kimura, Yuuya;Hatanaka, Toshiharu
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.559-564
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    • 2003
  • Recently, particle filters have attracted attentions for nonlinear state estimation. They evaluate a posterior probability distribution of the state variable based on observations in simulation using so-called importance sampling. However, degeneracy phenomena in the importance weights deteriorate the filter performance. A new filter, Evolution Strategies Based Particle Filter, is proposed to circumvent this difficulty and to improve the performance. Numerical simulation results illustrate the applicability of the proposed idea.

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여자역도 인상종목의 경기력 결정요인 산출 (Determination of Performance Determinant Factors in Snatch Weightlifting)

  • 문영진
    • 한국운동역학회지
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    • 제15권2호
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    • pp.21-29
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    • 2005
  • The Purpose of this study was to seek determinant factors through analysis of 65 snatch skill kinematic factors of Athletics participated in 2001 Asian weightlifting competetion. The conclusion were as follows ; 1. In order to enhance snatch skill, when barbell move on knee position, One should be flex knee joint to 105-110 degree, and In pull motion, One should be move powerful extension of knee and hip joint. 2. In last pull motion, One try to make more lock out motion than extra extention motion of hip joint 3. In order to enhance snatch skill, It is inportant that elevate barbell highly by last pull motion through powerful knee extention, poweful hip flextion and One should be make lock out motion fast in the same time. 4. In order to enhance snatch skill, anterior-posterior movement width of shoulder joint should be small. 5. In order to enhance snatch skill, Hip joint should be move vertically on start and lock out phase, but In pull phase, extension motion of hip joint shoulde be performed more largely and powerfully.

SPLICE 방법에 기반한 잡음 환경에서의 음성 인식 성능 향상 (Performance Improvement ofSpeech Recognition Based on SPLICEin Noisy Environments)

  • 김종현;송화진;이종석;김형순
    • 대한음성학회지:말소리
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    • 제53호
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    • pp.103-118
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    • 2005
  • The performance of speech recognition system is degraded by mismatch between training and test environments. Recently, Stereo-based Piecewise LInear Compensation for Environments (SPLICE) was introduced to overcome environmental mismatch using stereo data. In this paper, we propose several methods to improve the conventional SPLICE and evaluate them in the Aurora2 task. We generalize SPLICE to compensate for covariance matrix as well as mean vector in the feature space, and thereby yielding the error rate reduction of 48.93%. We also employ the weighted sum of correction vectors using posterior probabilities of all Gaussians, and the error rate reduction of 48.62% is achieved. With the combination of the above two methods, the error rate is reduced by 49.61% from the Aurora2 baseline system.

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주관절 원발성 골성 관절염의 관절경적 전방 변연 절제술 및 최소 절개 후방 절제술 (Arthroscopic Anterior Debridement and Mini-Open Posterior Resection for Primary Osteoarthritis of the Elbow)

  • 김영규;문성훈;조승현;오원석
    • 대한관절경학회지
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    • 제16권1호
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    • pp.40-46
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    • 2012
  • 목적: 주관절의 원발성 골성 관절염의 치료로 관절경적 전방 변연 절제술 및 최소 절개를 이용한 후방 골극 절제술을 시행하여 이 술식의 유용성을 알아보고자 하였다. 대상 및 방법: 2003년 3월부터 2010년 2월까지 불응성 주관절 골성 관절염의 치료로 관절경적 전방 변연 절제술 및 최소 절개 하 후방 골극 절제술을 시행한 19예를 대상으로 하였다. 추시 기간은 평균 19개월이었으며, 평균 연령은 49세였다. 결과는 Andrew-Carson Rating Scale (ACRS)과 Mayo Elbow Performance Score (MEPS)를 이용하여 평가하였다. 결과: 운동 범위는 굴곡 구축이 수술 전 $28.7^{\circ}$에서 수술 후 $17.9^{\circ}$, 후속 굴곡은 $105.1^{\circ}$에서 $121.8^{\circ}$로 증가하였다. MEPS는 51.1점에서 수술 후 87.9점으로 호전되어 우수 3예, 양호 13 예, 보통 3예를 보였다. ACRS는 92.9점에서 수술 후 168.2점으로 호전되어 우수 3예, 양호 14예, 보통 2예를 보였다. 1예를 제외한 전 예에서 일상생활에 지장이 없이 이전 직업으로 복귀하였다. 결론: 불응성 주관절 골성 관절염의 치료로 관절경적 전방 변연 절제술 및 최소 절개 하 후방 골극 절제술은 동통 완화 및 기능 회복에 도움이 되는 술식이라 생각된다. 그러나 골극의 재발이나 관절염의 진행 여부는 장기적 추시가 필요할 것으로 사료된다.

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