• Title/Summary/Keyword: National labs

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How can We Make Satisfiable Dental Restorations? (모두에게 만족을 주는 보철물은 어떻게 만들어지는가?)

  • Ahn, Seung-Geun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.21 no.2
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    • pp.183-189
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    • 2005
  • There is no single or simple answer for effective communication between laboratory technician and clinical dentist. Love-hate could be used to describe the relationship between dentists and their labs. Great lab work can make a dentists life much easier and can result in getting many referrals. However, if the lab work is not up to par and/or late, it can add stress and agony to a dentists practice. Also the opposition is right. If the preparations are calibrated, the impressions clear, and the bite registrations accurate, most labs can do their work reasonably well. Unfortunately, many cases received by labs are barely adequate, especially when it comes to reading margins, which are frequently created by the imagination of the person trimming the dies. In other words, both dentists and lab technicians need to be able to understand how each party operates so that solutions to problems can be found. Effective communication with the laboratory is critical if any degree of success is desired.

Engineering Experiments and Practices on Measurement and Control using Graphical Program (그래피칼 프로그램을 이용한 계측 및 제어 공학 실험실습)

  • Ghaly, Mikhail;Choi, Seong-Joo
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.4 no.1
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    • pp.65-71
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    • 2012
  • This paper introduces computer based practice for engineering education through using NI-ELVIS and virtual instruments of LabVIEW as application software. Different laboratory experiments "Labs" will be presented as convenient paradigms of adopting computer based practice for the efficacy of engineering education. Remote labs as web/internet or network-enabled controlled by remote server computer have been extensively used by a number of universities, national laboratories and companies for different kind of application around the globe. Overtime, as technology proceed in its progress, more developed techniques are being used particularly in the field of engineering education.

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Mutation spectrum of NF1 gene in Korean unrelated patients with neurofibromatosis 1: Six novel pathogenic variants

  • Sung Hee Han;Eun Joo Kang;Mina Yang;Suekyeung Kim;Sang Gon Lee;Eun Hee Lee
    • Journal of Genetic Medicine
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    • v.21 no.1
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    • pp.22-30
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    • 2024
  • Purpose: Neurofibromatosis 1 (NF1) is one of the most common autosomal dominant diseases caused by heterozygous mutation in the NF1 gene. Mutation detection is complex owing to the large size of the NF1 gene, the presence of a high number of partial pseudogenes, and the great variety of mutations. We aimed to study the mutation spectrum of NF1 gene in Korean patients with NF1. Materials and Methods: We have analyzed total 69 unrelated patients who were clinically diagnosed with NF1. PCR and sequencing of the NF1 gene was performed in all unrelated index patients. Additionally, multiplex ligation-dependent probe amplification (MLPA) test of the NF1 and SPRED1 gene analysis (sequencing and MLPA test) were performed in patients with negative results from NF1 gene sequencing analysis. Results: Fifty-five different variants were identified in 60 individuals, including six novel variants. The mutations included 36 single base substitutions (15 missense and 21 nonsense), eight splicing mutations, 13 small insertion or deletions, and three gross deletions. Most pathogenic variants were unique. The mutations were evenly distributed across exon one through 58 of NF1, and no mutational hot spots were found. When fulfilling the National Institutes of Health criterion for the clinical diagnosis of NF1, the detection rate was 84.1%. Cafe-au-lait macules were observed in all patients with NF1 mutations. There is no clear relationship between specific mutations and clinical features. Conclusion: This study revealed a wide spectrum and genetic basis of patients with NF1 in Korea. Our results aim to contribute genetic management and counseling.

Analysis of the Microstructure and Oxidation Behavior of Some Commercial Carbon Fibers

  • Kim, Dae-Ho;Kim, Bo-Hye;Yang, Kap-Seung;Bang, Yun-Hyuk;Kim, Sung-Ryong;Im, Hun-Kook
    • Journal of the Korean Chemical Society
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    • v.55 no.5
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    • pp.819-823
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    • 2011
  • The relationship between the microstructure, mechanical properties, and oxidation behavior of pitch-, polyacrylonitrile (PAN)-, and Rayon-based carbon fibers (CFs) has been studied in detail. Three types of carbon fiber were exposed to isothermal oxidation in air and the weight change was measured by thermogravimetric analyzer (TGA) apparatus. After activation energy was gained according to the conversion at reacting temperature, the value of specific surface area and the surface morphology was compared, and the reaction mechanism of oxidation affecting development of pores of carbon fibers was examined. This study will lead to a new insight into the relationship between the microstructure and mechanical properties of carbon fibers.

Molecular structure effects of the pitches on preparation of activated carbon fibers from electrospinning

  • Kim, Bo-Hye;Wazir, Arshad Hussain;Yang, Kap-Seung;Bang, Yun-Hyuk;Kim, Sung-Ryong
    • Carbon letters
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    • v.12 no.2
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    • pp.70-80
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    • 2011
  • Two pitches with different average molecular structures were electrospun and compared in terms of the properties of their fibers after oxidative stabilization, carbonization, and activation. The precursor with a higher molecular weight and greater content of aliphatic groups (Pitch A) resulted in better solubility and spinnability compared to that with a lower molecular weight and lower aliphatic group content (Pitch B). The electrical conductivity of the carbon fiber web from Pitch A of 67 S/cm was higher than that from Pitch B of 52 S/cm. The carbon fiber web based on Pitch A was activated more readily with lower activation energy, resulting in a higher specific surface area compared to the carbon fiber based on Pitch B (Pitch A, 2053 $m^2/g$; Pitch B, 1374 $m^2/g$).

Effect of Rhodophyta extracts on in vitro ruminal fermentation characteristics, methanogenesis and microbial populations

  • Lee, Shin Ja;Shin, Nyeon Hak;Jeong, Jin Suk;Kim, Eun Tae;Lee, Su Kyoung;Lee, Sung Sill
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.1
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    • pp.54-62
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    • 2018
  • Objective: Due to the threat of global warming, the livestock industry is increasingly interested in exploring how feed additives may reduce anthropogenic greenhouse gas emissions, especially from ruminants. This study investigated the effect of Rhodophyta supplemented bovine diets on in vitro rumen fermentation and rumen microbial diversity. Methods: Cannulated Holstein cows were used as rumen fluid donors. Rumen fluid:buffer (1:2; 15 mL) solution was incubated for up to 72 h in six treatments: a control (timothy hay only), along with substrates containing 5% extracts from five Rhodophyta species (Grateloupia lanceolata [Okamura] Kawaguchi, Hypnea japonica Tanaka, Pterocladia capillacea [Gmelin] Bornet, Chondria crassicaulis Harvey, or Gelidium amansii [Lam.] Lamouroux). Results: Compared with control, Rhodophyta extracts increased cumulative gas production after 24 and 72 h (p = 0.0297 and p = 0.0047). The extracts reduced methane emission at 12 and 24 h (p<0.05). In particular, real-time polymerase chain reaction analysis indicated that at 24 h, ciliate-associated methanogens, Ruminococcus albus and Ruminococcus flavefaciens decreased at 24 h (p = 0.0002, p<0.0001, and p<0.0001), while Fibrobacter succinogenes (F. succinogenes) increased (p = 0.0004). Additionally, Rhodophyta extracts improved acetate concentration at 12 and 24 h (p = 0.0766 and p = 0.0132), as well as acetate/propionate (A/P) ratio at 6 and 12 h (p = 0.0106 and p = 0.0278). Conclusion: Rhodophyta extracts are a viable additive that can improve ruminant growth performance (higher total gas production, lower A/P ratio) and methane abatement (less ciliateassociated methanogens, Ruminococcus albus and Ruminococcus flavefaciens and more F. succinogenes.

A Study on Fault Alarming Architecture for ACE2000 MPLS Interface Module (ACE2000 MPLS 정합 모듈의 장애경보 구조 연구)

  • Park, Wan-Ki;Park, Dae-Geun;Jeong, Youn-Kwae;Kim, Dae-Young
    • Proceedings of the Korea Information Processing Society Conference
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    • 2001.10b
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    • pp.1497-1500
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    • 2001
  • ACE2000 MPLS 시스템은 국가 시스템으로 사용하기 위해 기 개발한 ACE2000 ATM 교환시스템에 Ships-in-the-night 모드 형태로 ATM 교환시스템에 MPLS 기능을 추가함으로써 사용자들에게 차별화된 서비스를 제공하도록 하는 시스템이다. MPLS 시스템 모듈인 MIM(MPLS Interface Module)은 1모듈이 2.5Gbps 의 대용량 패킷 포워딩 기능을 갖는 시스템으로서 BPAA, HALA, 가입자 정합 보드에 하드웨어 패킷 포워딩 및 VC 머징 기능을 갖는 HFMA 하드웨어 PBA 가 추가되어 모듈을 구성한다. ACE2000 MPLS 시스템에서는 MIM 모듈의 운용/보전을 위해 모듈내의 각 보드에 대하여 장애 발생시 하드웨어 및 소프트웨어적으로 MSC 에게 보고하도록 하고 있다. MIM 모듈에 대한 장애보고 체계는 하드웨어적으로는 각 보드의 탈/실장, 전원 장애, 기능장애 등을 경보계통을 통해서 보고하는 구조로 이루어져 있고, 소프트웨어적으로는 ATM IPC 채널을 이용한 경보체계를 이용하여 보고함으로써 시스템의 원활한 시스템 운용/보전에 활용하고 있다. 본 논문에서는 이러한 ACE2000 MPLS 시스템의 장애경보(Fault Alarming) 방법 및 그 구조에 대하여 언급하였다.

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Character-Level Neural Machine Translation (문자 단위의 Neural Machine Translation)

  • Lee, Changki;Kim, Junseok;Lee, Hyoung-Gyu;Lee, Jaesong
    • Annual Conference on Human and Language Technology
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    • 2015.10a
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    • pp.115-118
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    • 2015
  • Neural Machine Translation (NMT) 모델은 단일 신경망 구조만을 사용하는 End-to-end 방식의 기계번역 모델로, 기존의 Statistical Machine Translation (SMT) 모델에 비해서 높은 성능을 보이고, Feature Engineering이 필요 없으며, 번역 모델 및 언어 모델의 역할을 단일 신경망에서 수행하여 디코더의 구조가 간단하다는 장점이 있다. 그러나 NMT 모델은 출력 언어 사전(Target Vocabulary)의 크기에 비례해서 학습 및 디코딩의 속도가 느려지기 때문에 출력 언어 사전의 크기에 제한을 갖는다는 단점이 있다. 본 논문에서는 NMT 모델의 출력 언어 사전의 크기 제한 문제를 해결하기 위해서, 입력 언어는 단어 단위로 읽고(Encoding) 출력 언어를 문자(Character) 단위로 생성(Decoding)하는 방법을 제안한다. 출력 언어를 문자 단위로 생성하게 되면 NMT 모델의 출력 언어 사전에 모든 문자를 포함할 수 있게 되어 출력 언어의 Out-of-vocabulary(OOV) 문제가 사라지고 출력 언어의 사전 크기가 줄어들어 학습 및 디코딩 속도가 빨라지게 된다. 실험 결과, 본 논문에서 제안한 방법이 영어-일본어 및 한국어-일본어 기계번역에서 기존의 단어 단위의 NMT 모델보다 우수한 성능을 보였다.

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Link Analysis of Korean Web Graph (국내 웹 그래프의 링크 구조 분석)

  • Seo, Jung-Joo;Kim, Jin-Il;Kim, Eun-Sang;Kim, Daniel;Jeong, Ha-Woong;Kim, Sung-Ryul;Park, Kun-Soo
    • Proceedings of the Korean Information Science Society Conference
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    • 2012.06a
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    • pp.400-402
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    • 2012
  • 웹을 구성하는 웹 페이지들과 페이지들 사이의 하이퍼링크들은 방향성을 지니는 그래프로써 표현될 수 있으며, 웹 그래프가 가지는 독자적인 링크 구조의 특성은 다양한 분야의 연구에서 활용되고 있다. 현재 검색 엔진들이 수집한 웹 페이지들은 그 규모가 수십억 개로 방대한 양을 이루고 있다. 본 논문에서는 약 3억 개의 국내 웹 페이지들을 수집하고, 링크 데이터를 추출하여 생성한 웹 그래프의 구조에 대해 분석한다. 국내 웹 페이지들의 링크의 진입 차수와 연결 요소들의 크기 분포는 멱법칙을 따르고, 웹 페이지의 진출 차수는 특정 차수 이상에서 멱법칙을 가짐을 확인한다. 또한 그래프 알고리즘을 이용하여 웹 그래프를 구성하는 요소들로 나눈 후 전체적인 구조를 도식화한 보우타이 다이어그램을 도출한다.