• The korean journal of orthodontics
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• v.30 no.6 s.83
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• pp.731-738
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• 2000

The purpose of this study was to investigate the change of 3 point bending properties of various nickel titanium wires after recycling. Four Types of nickel-titanium (Align: martensitic type, NiTi, Optimalloy, Sentalloy: austenitic type) wires were divided to three groups: as-received condition (T0: control group), treated in artificial saliva for four weeks (T1) and autoclaved after being treated in artificial saliva (T2). Detrimental changes were observed for the selected mechanical properties in three point bending test. Loading force at 3mm deflection, unloading force at 3mm deflection, stress hysteresis, loading force at 1mm deflection, unloading force at 1mm deflection and stress hysteresis at 1mm deflection were calculated. The findings suggest that : 1. Align demonstrated statistically significant increase In loading force (p<0.05) and unloading force (p<0.01) at 3mm deflection after recycling(T2), but NiTi, Optimalloy and Sentalloy showed no statistically difference after recycling. 2. Align demonstrated statistically significant decrease in hysteresis(p<0.01) after recycling(T2) but NiTi, Optimalloy and Sentalloy showed no statistically significant difference after recycling. 3. All wires showed no statistically significant difference in loading force at 1mm deflection after recycling(T2). 4. Align demonstrated statistically significant decrease in unloading force in 1mm deflection (p<0.05) after recycling(T2) but NiTi, Optimalloy and Sentalloy showed no statistically difference after recycling 5. Loading force and unloading force of T1 showed no significant change compared with those of T0, but loading force and unloading force of T2 showed significant changes compared with those of T0(p<0.05, p<0.01 respectively). 6. Align demonstrated a tendency to lose some of this pseudoelasticity in T1 and pseudoplasticity and pseudoelasticity in T2.

• The Korean Journal of Applied Statistics
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• v.14 no.1
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• pp.25-37
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• 2001

The marginal model is proposed for the analysis of data which have c(2: 3) categories in the 3 x 3 cross-over trials with three periods and three treatments. This model could be used for the counterpart of the Kenward-Jones' joint probability one and should be the generalization of Balagtas et ai's univariate marginal logits one, which analyze the treatment effects in the 3 x 3 cross-over trials with binary response variables[Kenward and Jones(1991), Balagtas et al(1995)]. The model equations for the marginal probability are constructed by the three types of link functions. The methods would be given for making of the link function matrices and model ones, and the estimation of parameters shall be discussed. The proposed model is applied to the analysis of Kenward and Jones' data.

• The Korean Journal of Applied Statistics
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• v.22 no.1
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• pp.181-188
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• 2009

This paper discusses the covariance structures of data collected from an experiment with a nested design structure, where a smaller experimental unit is nested within a larger one. Due to the nonrandomization of repeated measures factors to the nested experimental units, compound symmetry covariance structure is assumed for the analysis of data. Treatments are given as the combinations of the levels of random factors and fixed factors. So, a mixed-effects model is suggested under compound symmetry structure. An example is presented to illustrate the nesting in the experimental units and to show how to get the parameter estimates in the fitted model.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.04a
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• pp.1163-1165
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• 2017

헬스케어와 IT가 결합한 융합산업이 발전하면서 웨어러블 디바이스와 스마트폰을 연계하여 운동정보를 제공하는 제품이 증가하고 있다. 특히 손목에 착용하는 스마트밴드를 통해 생체신호 및 움직임을 감지하고 신체상태 및 활동량을 제공하고 있다. 그러나 단순한 운동 동작의 횟수나 시간만을 알려주는 서비스를 제공하고 있어 정확한 운동 및 건강의 관리가 힘들다. 이에 본 논문에서는 사용자에게 운동의 정확성 여부를 알려주고 건강 및 운동에 대한 통계 정보를 제공하는 클라우드 서비스 기반의 운동 정보 제공 시스템을 제안한다. 제안 시스템은 스마트밴드와 모션 디바이스를 통해 모션 및 심박데이터를 취득하여 스마트폰을 통해 실시간으로 운동의 정확도 여부 및 활동 정보를 제공한다. 또한 클라우드 플랫폼의 서비스 가상 머신을 통해 세밀한 운동 자세 및 운동량, 신체 상태 통계 등의 피드백 서비스를 제공한다.

• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.175-182
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• 1998

Any classification process using SAR images presupposes the reduction of multiplicative speckle noise, since the variations caused by speckle make it extremely difficult to distinguish between neighboring classes within the feature space. Therefore, several adaptive filter algorithms have been developed in order to distinguish between them. These algorithms aim at the preservation of edges and single scattering peaks, and smooths homogeneous areas as much as possible. This task is rendered more difficult by the multiplicative nature of the speckle noise the signal variation depends on the signal itself. In this paper, LEE(Lee 1908) and R-LEE(Lee 1981) filters using local statistics, local mean and variance, are applied to RADARSAT SAR images. Also, a new method of speckle filtering, EPOS(Edge Preserving Optimal Speckle)(Hagg & Sties 1994) filter based on the statistical properties of speckle noise is described and applied. And then, the results of filtering SAR images with LEE, R-LEE and EPOS filters are compared with mean and median filters.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.36-43
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• 2013

Fully homomorphic encryption is a cryptography system in which coded data can be searched and statistically processed without decryption. Fully homomorphic encryption has accelerated searching speed by minimizing time spent on encryption and decryption. In addition, it is also known to prevent leakage of any data decoded for statistical reasons. Also, it is expected to protect personal information stored in the cloud computing environment which is becoming commercialized. Since the 1970s when fully homomorphic encryption was first introduced, it has been researched to develop the algorithm that satisfy effectiveness and functionality. We will take the reader through a journey of these developments and provide a glimpse of the exciting research directions that lie ahead.

• Annual Conference on Human and Language Technology
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• 2012.10a
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• pp.95-98
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• 2012

말뭉치는 언어를 연구하기 위한 중요한 재료이다. 본 논문에서는 말뭉치에서 나타나는 언어 현상을 보다 효율적으로 분석하기 위한 언어학자를 위한 말뭉치 분석기를 제안하고 그 구현 방법을 설명한다. 제안하는 말뭉치 분석기는 기본적인 통계 정보와 함께, 형태소 분석된 파일을 대상으로 위치 색인을 포함하는 역파일 색인을 구성하여 빠른 형태소 검색과 다앙한 수준의 연어 검색을 제공한다. 분석기는 세종말뭉치를 기본 말뭉치로 하며, 다앙한 말뭉치에 대한 통계자료와 검색 기능을 제공하기 위해 사용자 말뭉치 파일에 대한 처리도 지원한다. 시스템은 사용자가 업로드한 말뭉치 파일에 대하여 자동 형태소 분석을 제공하며 형태소 분석 결과 수정을 가능하게 하여 다앙한 말뭉치에서 언어학자들의 우리말 연구를 지원한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8A
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• pp.1208-1217
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• 1999

Being increased the errention and competition for communication business, the economical efficiency and the reliance of communication network were raised. The communication operators are sensitively reactioned to the data related communication. Especially, the trend of hazards related to communication networks and users is broadly deviede into 3 classes in the technical specificatons of foreigners. In this paper, the field data of parameters corresponding to 3 classes was statistically processed and compared to the specified values in the technical specification. The ststistical processes of field data play a role as an objective information for the service quality related to the communication network, and will be helpful for preparing the globalization of communication.

• The Korean Journal of Applied Statistics
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• v.27 no.5
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• pp.819-831
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• 2014

The Exact-EM algorithm can conventionally fit a mixture of multivariate skew distribution. However, it suffers from highly expensive computational costs to calculate the moments of multivariate truncated t-distribution in E-step. This paper proposes a new SPU-EM method that adopts the AECM algorithm principle proposed by Meng and van Dyk (1997)'s to circumvent the multi-dimensionality of the moments. This method offers a shorter execution time than a conventional Exact-EM algorithm. Some experments are provided to show its effectiveness.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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• pp.673-676
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• 2000

본 논문에서는 네트워크 트래픽 분석은 물론 자원을 관리하고 서버 및 특정 서비스에 대하 분석 자료를 제공하는 통합 시스템을 자바 언어로 구현하였다. SNMP 지원 모듈과 TCPdump 모듈, 그리고 시스템 관리 명령 모듈 등을 이용하여 구성 관리, 성능 관리, 장애 관리 및 시스템 자원 관리와 같은 상세 정보의 제공과 함에 다양한 자료 수집과 통계 분석을 통해 상세 보고서를 생성한다. 뿐만 아니라, 관리 대상 범위를 도메인 별로 구분하여 자료 수집을 독립시킴으로써 관리를 위한 트래픽이 전체 네트워크에 영향을 미치지 않도록 설계하였고, 실시간 모니터링은 물론 DB 에 최소화된 자료를 유지함으로써 네트워크 및 시스템에 대한 영속적인 관리 및 통계가 가능하도록 하여 운영의 항구성과 안정성, 분석의 정확성과 일치성, 사용의 편의성과 효용성을 제공하고자 하였다.