• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1618-1622
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• 2004

In this paper, the linearly interpolated PRC(Pseudo Range Correction) regenerating algorithm was applied to improve the DGPS(Differential Global Positioning System) positioning accuracy at user's spot by using the various PRC information obtained from multi-DGPS reference stations. The PRC information of each GPS satellite is not varying rapidly; it is possible to assume that the variation of PRC information of each GPS satellite is linear. So the linearly interpolated PRC regenerating algorithm can be applied to improve the DGPS positioning accuracy at user's spot by using the various PRC information obtained from multi-DGPS reference stations. To test the performance of the linearly interpolated PRC regenerating algorithm, maritime DGPS reference stations' PRC data was used in RTCM format. 11 maritime DGPS reference stations are in service providing DGPS information to public since 1999. Two set of 3 DGPS reference stations are selected to compare the performance of the linearly interpolated PRC regenerating algorithm. The DGPS positioning accuracy was dramatically improved about 40%. Linearly interpolated PRC regenerating algorithm adopted multi-channel DGPS receiver will be developed in near future.

• BMB Reports
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• v.55 no.12
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• pp.595-601
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• 2022

Polycomb Repressive Complex 2 (PRC2) exhibits key roles in mammalian development through its temporospatial repression of gene expression. EZH1 or EZH2 is the catalytic subunit of PRC2 that mediates the mono-, di- and tri-methylation of histone H3 lysine 27 (H3K27me1/2/3), H3K27me2/me3 being a hallmark of facultative heterochromatin. PRC2 is a chromatin-modifying enzyme that is recruited to a limited number of "nucleation sites", spreads H3K27 methylation and fosters chromatin compaction. EZH1 and EZH2 exhibit differences in their expression patterns, levels of histone methyltransferase activity (HMT) in the context of PRC2, and DNA/nucleosome binding activity. This suggests that their roles in heterochromatin formation are disparate. Dysregulation of PRC2 activity leads to aberrant gene expression and is implicated in cancer and developmental diseases. In this review, we discuss the distinct function of PRC2/EZH1 and PRC2/EZH2 in the early and late developmental stages. We then discuss the cancers associated with PRC2/EZH1 and PRC2/EZH2.

• Journal of Life Science
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• v.18 no.10
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• pp.1395-1399
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• 2008

We have recently reported the PRC1 promoter as a promoter candidate to control expression of transcriptionally targeted genes for breast cancer gene therapy. We tested whether the PRC1 promoter could be also applied for the lung cancer gene therapy. In the transient transfection assay with naked plasmids containing the luciferase fused to the PRC1 promoter, the promoter showed little activity in the normal lung cell line, MRC5. However, in the lung cancer A549 cells, PRC1 showed approximately 30-fold activation which was similar to the survivin promoter, the gene whose promoter has been already reportedas a candidate for the gene therapy of lung cancer. In viral systems, the PRC1 promoter showed approximately 75% and 66% of transcriptional activity compared to the CMV promoter in the adeno-associated virus (AAV) and the adenovirus (AV) systems, respectively. However, the PRC1 promoter in either AAV or AV showed approximately 20% activity compared to the CMV promoter in the normal lung cells. In addition, human lung tumor xenograft mice showed that the PRC1 promoter activity was as strong as the CMV activity in vivo. Taken together, these results suggested that PRC1 might be a potential promoter candidate for transcriptionally targeted lung cancer gene therapy.

• Molecules and Cells
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• v.37 no.12
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• pp.841-850
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• 2014

Polycomb group (PcG) proteins are conserved chromatin regulators involved in the control of key developmental programs in eukaryotes. They collectively provide the transcriptional memory unique to each cell identity by maintaining transcriptional states of developmental genes. PcG proteins form multi-protein complexes, known as Polycomb repressive complex 1 (PRC1) and Polycomb repressive complex 2 (PRC2). PRC1 and PRC2 contribute to the stable gene silencing in part through catalyzing covalent histone modifications. Components of PRC1 and PRC2 are well conserved from plants to animals. PcG-mediated gene silencing has been extensively investigated in efforts to understand molecular mechanisms underlying developmental programs in eukaryotes. Here, we describe our current knowledge on PcG-mediated gene repression which dictates developmental programs by dynamic layers of regulatory activities, with an emphasis given to the model plant Arabidopsis thaliana.

• Proceedings of the KIPE Conference
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• 2004.11a
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• pp.54-58
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• 2004

본 연구에서는 고정 주파수를 갖는 유사 랜덤 주파수 캐리어 PW(PRC-PWM)을 제안하고 단상 5-레벨 캐스케이드 인버터에 적용하였다. 제안된 PRC-PWM의 펄스는 고정 주파수를 갖는 삼각파 캐리어와 그 역상의 삼각파 캐리어를 랜덤 비트 발생기(PRBS)에 의하여 랜덤하게 선택함으로서 새롭게 합성된 랜덤 주파수의 캐리어에서 얻고 있다. 제안된 PRC-PWM은 고정 주파수의 캐리어 합성만으로 랜덤 주파수의 캐리어를 매우 간단하게 구현할 수 있으며, R-L부하와 연결된 단상 5-레벨 캐스케이드 인버터를 제작하여 타당성을 입증하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.8C
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• pp.771-776
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• 2006

We present a suboptimum decoding method for space-time trellis codes, which include maximum $likelihood(ML)^{[1]}$ and principal ratio $combining(PRC)^{[2]}$, over quasi-static flat fading channels. In the proposed scheme, the receive antennas are divided into K groups and the PRC is applied to each group, showing a flexible performances between ML and PRC. When K is determined, we also propose the optimum grouping rules and performance index(PI), which simply anticipate the relative performances. Moreover the performances are also evaluated when receive antennas are correlated. Finally, Computer simulations corroborate those theoretical results.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.26 no.3
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• pp.217-225
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• 2015

Objectives : The objective of this study was to compare the Korean Personality Rating Scale for Children (K-PRC) profile between children with attention-deficit hyperactivity disorder (ADHD) and typically developing children. We also aimed to investigate the association of K-PRC and ADHD symptoms. Methods : Ninety-nine youth (age $8.3{\pm}2.4$ years, 72 boys) with ADHD and 84 controls (age $9.2{\pm}2.5$ years, 43 boys) were recruited from the Department of Pediatric Psychiatry of the Asan Medical Center Children's Hospital. Diagnoses of ADHD and comorbid psychiatric disorders were confirmed with the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version (K-SADS-PL). The parents of the subjects completed the ADHD rating scale, and K-PRC. Independent t-tests, analysis of covariance, partial correlation analyses, and Mc Nemar test were used for analysis. Results : Children and adolescents with ADHD showed higher K-PRC scores in verbal development, physical development, depression, delinquency, hyperactivity, family dysfunction and psychoticism. Delinquency and hyperactivity were significantly correlated with parent-rated ADHD rating scales and ADHD scores on K-SADS-PL. The hyperactive/impulsive and combined subtypes showed higher scores on hyperactivity and delinquency than the inattentive subtype, and the inattentive subtype showed higher scores on depression and social dysfunction of the K-PRC. Conclusion : Our results suggest that K-PRC could be used to comprehensively evaluate symptoms, combined psychopathologies, developmental delay and family dysfunction of children with ADHD.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.1 s.343
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• pp.89-94
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• 2006

We present a generalized version of principal ratio combining (PRC)[1], which is a near-optimum decoding scheme for space-time trellis codes in quasi-static flat fading environments. In [1], the performance penalty increases as the number of receive antennas increases. In the proposed scheme, receive antennas are divided into K groups, and the PRC decoding method is applied to each group. This shows a flexible tradeoff between performance and decoding complexity by choosing the appropriate K. Moreover, we also propose the performance index(PI) to easily predict the decoding performance among the possible different(receive antenna) configurations.

• Proceedings of the Korean Society for Information Management Conference
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• 2010.08a
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• pp.21-28
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• 2010

본 연구에서는 PubMed에 등재되었으나 Medical Subject Headings(MeSH)가 부여되지 않은 국내 의학학술지의 문헌을 대상으로 미국국립의학도서관 (NLM: National Library of Medicine)의 Medical Text Indexer(MTI)를 활용하여 MeSH 용어를 추천받은 후, PubMed 레코드의 유사주제문헌 (Relation Citations, PRC)에 부여된 MeSH와의 일치여부를 분석하였다. 또한 논문의 저자가 부여한 키워드(저자키워드)와 PRC MeSH의 일치여부도 비교하였다. PRC MeSH와 MTI MeSH 추천어의 일치율은 주표목이 21.1%였고, 체크태그는 18.1%, 부표목은 16.5%로 나타났다. 우리나라 의학논문에 나타난 저자키워드의 중요한 특징은 MeSH 주표목 위주이고, 체크태그와 부표목은 거의 사용하지 않는 것이다. 따라서 저자키워드와 PRC MeSH 주표목과의 일치율은 23.4%에 이르지만, 체크태그와 부표목의 일치율은 각각 1%, 2.1%였다. 색인전문가가 통제어휘를 사용하여 색인하는 과정에서 PRC와 MTI의 MeSH 주표목과 저자키워드가 일치하는 용어를 주표목으로 부여하고, PRC와 MTI가 추천하는 체크태그와 부표목을 활용하는 등 국내 의학문헌의 MeSH 용어 부여 작업을 반자동화(semi-indexing)하면, 정확하고 신속한 MeSH 부여 작업이 가능할 것이다.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.4
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• pp.43-48
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• 2015

We studied on pseudo-range correction(PRC) modeling in order to improve differential GNSS(DGNSS) accuracy. The PRC is the range correction information that provides improved location accuracy using DGNSS technique. The digital correction signal is typically broadcast over ground-based transmitters. Sometimes the degradation of the positioning accuracy caused by the loss of PRC signals, radio interference, etc. To prevent the degradation, in this paper, we have designed a PRC model through polynomial curve fitting and evaluated this model. We compared two quantities, estimations of PRC using model parameters and observations from the reference station. In the case of GPS, the average is 0.1m and RMSE is 1.3m. Most of GPS satellites have a bias error of less than ${\pm}1.0m$ and a RMSE within 3.0m. In the case of GLONASS, the average and the RMSE are 0.2m and 2.6m, respectively. Most of satellites have less than ${\pm}2.0m$ for a bias error and less than 3.0m for RMSE. These results show that the estimated value calculated by the model can be used effectively to maintain the accuracy of the user's location. However;it is needed for further work relating to the big difference between the two values at low elevation.