• 제목/요약/키워드: USL

검색결과 22건 처리시간 0.022초

핵임계 안전성 검증 방법론 정립 및 적용 (Establishment and Application of Nuclear Criticality Safety Validation Methodology)

  • 이서정;차균호
    • 방사성폐기물학회지
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    • 제16권3호
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    • pp.315-330
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    • 2018
  • 미임계 시설은 정상 또는 사고상태에서 핵임계안전성이 확보되어야 한다. 이를 위해선 계산된 임계도가 바이어스와 불확실도로 결정된 미임계상한치(USL)를 초과하지 않는다는 것을 검증하는 절차가 반드시 필요하다. 하지만 핵임계안전성 검증방법론은 여러 가지가 존재하며, 방법론이 달라지면 USL도 달라지므로 가장 적절한 한가지의 방법론으로 평가하는 것이 중요하다. 본 연구에서는 핵임계안전성 검증 방법론이 기술된 두 개의 문서를 비교 분석하여 한 가지 방법론으로 정립하였고, SCALE6.1 코드를 이용한 용기 설계에서의 미임계상한치 결정에 적용하였다.

VLM-ST용 CAD/CAM 시스템에서 단위 형상층 생성 방법 및 적용예 (Generation of Unit Shape Layer on CAD/CAM System for VLM-ST)

  • 이상호;안동규;최홍석;양동열;문영복;채희창
    • 한국CDE학회논문집
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    • 제7권3호
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    • pp.148-156
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    • 2002
  • Most Rapid Prototyping (RP) processes adopt a solid Computer Aided Design (CAD) model, which will be sliced into thin layers of constant thickness in the building direction. Each cross-sectional layer is successively deposited and, simultaneously, bonded onto the previous layer; and eventually the stacked layers from a physical part of the model. A new RP process, the transfer-type Variable Lamination Manufacturing process using expandable polystyrene foam sheet (VLM-ST), has been developed to reduce building time and to improve the surface finish of parts with the thick layers and a sloping surface. This paper describes the generation of Unit Shape Layer (USL), the cutting path data of the linen. hotwire cutter for the VLM-ST process. USL is a three-dimensional layer with a thickness of more than 1 mm and a side slope, and it is the basic unit of cutting and building in the VLM-ST process. USL includes data such as layer thickness, positional coordinates, side angles of each layer, hotwire cutting speed, the heat input to the hotwire, and reference shape. The procedure of generating USL is as follows: (1)Generation of the mid-slice from the CAD model, (2)Conversion of the mid-slice into a simply connected domain, (3)Generation to the reference shape for the mid-slice, (4)Calculation of the rotation angle of the hotwire of the cutting system.

Endoscopic submucosal dissection in colorectal neoplasia performed with a waterjet system-assisted knife: higher en-bloc resection rate than conventional technique

  • Paolo Cecinato;Matteo Lucarini;Francesco Azzolini;Mariachiara Campanale;Fabio Bassi;Annalisa Cippitelli;Romano Sassatelli
    • Clinical Endoscopy
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    • 제55권6호
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    • pp.775-783
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    • 2022
  • Background/Aims: Colorectal endoscopic submucosal dissection (ESD) is burdened by its associated high risk of adverse events and long procedure time. Recently, a waterjet-assisted knife was introduced to simplify and speed up the procedure. The aim of this study was to evaluate the efficacy and safety of waterjet-assisted ESD (WESD) compared to that of the conventional ESD (CESD) technique. Methods: The charts of 254 consecutive patients who underwent colorectal ESD between January 2014 and February 2021 for colorectal neoplasms were analyzed. The primary outcome was the en-bloc resection rate. Secondary outcomes were complete and curative resection rates, the need to switch to a hybrid ESD, procedure speed, the adverse event rates, and the recurrence rates. Results: Approximately 174 neoplasias were considered, of which, 123 were removed by WESD and 51 by CESD. The en-bloc resection rate was higher in the WESD group (94.3% vs. 84.3%). Complete resection rates and curative resection rates were similar. The need to switch to a hybrid ESD was greater during CESD (39.2% vs. 13.8%). Procedure speed and adverse event rates were similar. During follow-up, one recurrence occurred after a WESD. Conclusions: WESD allows a high rate of en-bloc resections and less frequently requires a rescue switch to the hybrid ESD compared to CESD.

Recognition Performance Improvement of Unsupervised Limabeam Algorithm using Post Filtering Technique

  • Nguyen, Dinh Cuong;Choi, Suk-Nam;Chung, Hyun-Yeol
    • 대한임베디드공학회논문지
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    • 제8권4호
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    • pp.185-194
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    • 2013
  • Abstract- In distant-talking environments, speech recognition performance degrades significantly due to noise and reverberation. Recent work of Michael L. Selzer shows that in microphone array speech recognition, the word error rate can be significantly reduced by adapting the beamformer weights to generate a sequence of features which maximizes the likelihood of the correct hypothesis. In this approach, called Likelihood Maximizing Beamforming algorithm (Limabeam), one of the method to implement this Limabeam is an UnSupervised Limabeam(USL) that can improve recognition performance in any situation of environment. From our investigation for this USL, we could see that because the performance of optimization depends strongly on the transcription output of the first recognition step, the output become unstable and this may lead lower performance. In order to improve recognition performance of USL, some post-filter techniques can be employed to obtain more correct transcription output of the first step. In this work, as a post-filtering technique for first recognition step of USL, we propose to add a Wiener-Filter combined with Feature Weighted Malahanobis Distance to improve recognition performance. We also suggest an alternative way to implement Limabeam algorithm for Hidden Markov Network (HM-Net) speech recognizer for efficient implementation. Speech recognition experiments performed in real distant-talking environment confirm the efficacy of Limabeam algorithm in HM-Net speech recognition system and also confirm the improved performance by the proposed method.

OSI 트랜스포트 계층에서의 보호시스템 개발 (Development of Security System in the OSI Transport Layer)

  • 박영호;김기현;문상재;강신각
    • 정보보호학회논문지
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    • 제5권1호
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    • pp.65-84
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    • 1995
  • 개방형 시스템에서 사용자에게 안전성 및 신뢰성을 보증하기 위하여 정보 보호가 필요하다.본 논문에서는 트랜스포트 계층에서 보호서비스를 제공하기 위하여 ISO와 IEC에서 표준으로 권고하고 있는 트랜스포트 계층 보호 프로토콜과 보호연관 프로토콜을 분석하고, 표준에서는 정의하지 않았으나 구현상 필요한 세부 사항들을 정의한다. 그리고 구현 모델을 제시하고 이에 기초하여 보호시스템을 개발한다. 개발을 위한 환경으로는 USL의 ONP를 사용한다.

인터네트워크에서의 전송데이타 보호시스템 개발 (A development of security system for transmission data in the internetwork)

  • 박영호;이국희;문상재
    • 전자공학회논문지S
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    • 제35S권4호
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    • pp.1-9
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    • 1998
  • This paper developments asecurity system for transmission data in the internetwork. Intermediate system of our model does not fulfill security service of confidentiality but authentication and integrity. Thus this model knows whether the transmission data on the intermediate system is authentic and integral or not, and it is practical and easy to be developmented. This system is developmented using a ONP of USL which prvides environments of the open system.

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OSI 트랜스포트 계층을 위한 보호 시스템의 개발 (The development of security system for OSI transport layer)

  • 김기현;박영호;문상재;박정수;신명기;강신각
    • 한국정보보호학회:학술대회논문집
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    • 한국정보보호학회 1994년도 종합학술발표회논문집
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    • pp.233-244
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    • 1994
  • 개방형 시스템에서 사용자에게 안전성 및 신뢰성을 보증하기 위하여 정보 보호가 필요하다. 본 논문에서는 트랜스포트 계층에서 보호 서비스를 제공하기 위하여 ISO와 IEC에서 표준으로 권고하고 있는 TLSP와 SA-P를 분석하고, 표준에서는 정의하지 않았으나 구현상 필요한 세부 사항들을 정의한다. 그리고 구현 모델을 제시하고 이에 기초하여 보호 시스템을 개발한다. 개발을 위한 환경으로는 USL의 ONP를 사용한다.

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삼차원 스캐너와 가변 적층 쾌속조형공정을 이용한 대형 입체 형상의 쾌속 제작 : 러쉬모어산 기념물 제작 사례 (Rapid Fabrication of Large-Sized Solid Shape using 3D Scanner and Variable Lamination Manufacturing : Case Study of Mount Rushmore Memorial)

  • 이상호;김효찬;송민섭;박승교;양동열
    • 대한기계학회논문집A
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    • 제28권12호
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    • pp.1958-1967
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    • 2004
  • This paper describes the method to rapidly fabricate the large-sized physical model with the envelope model size of more than 600 mm${\times}$ 600 mm${\times}$ 600 mm using two type semi-automatic VLM-ST processes in connection with the reverse engineering technology. The fabrication procedure of the large-sized solid shape is as follows: (1) Generation of STL data from 3D scan data using 3D scanner, (2) generation of shell-type STL data by Boolean operation, (3) division of shell-type STL data into several pieces by solid splitting, (4) generation of USL data for each piece with VLM-Slicer, (5) fabrication of each piece by cutting and stacking according to USL data using VLM-ST apparatus, (6) completion of a shell-type prototype by zigzag stacking and assembly for each piece, (7) completion of a 3D solid shape by foam backing, (8) surface finish of a completed 3D solid shape by coating and sanding. In order to examine the applicability of the proposed method, the miniature of the Mount Rushmore Memorial has been fabricated. The envelope model size of the miniature of the Mount Rushmore Memorial is 1,453 mm${\times}$ 760 mm${\times}$ 853 mm in size. From the result of the fabricated miniature of the Mount Rushmore Memorial, it has been shown that the method to fabricate the large object using two type semi-automatic VLM-ST processes in connection with the reverse engineering technology are very fast and efficient.

대학도서관의 전략적 계획 내용 분석 -미국, 영국, 캐나다, 호주 대학도서관을 중심으로 (A Comparative Analysis of Strategic Plans in University Libraries)

  • 조윤희
    • 정보관리학회지
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    • 제22권4호통권58호
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    • pp.111-128
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    • 2005
  • 최근 대학도서관은 물리적 장소로서 전통적인 도서관의 역할과 전자자원을 효율적으로 서비스 할 수 있는 가상도서관의 역할을 모두 수행해야 할 도전에 직면해 있다. 이에 대학도서관은 위기와 기회를 동시에 내포하고 있는 대학도서관의 미래를 적극적으로 설계하는 도구로서 전략적 계획을 수립하는 것이 필요하다. 본 연구는 미국, 영국, 캐나다, 호주 대학도서관의 전략적 계획의 실행 문서를 비교, 분석하여 그 내용을 형식적 요소와 내용적 요소로 구분하고 전략적 계획 문서에 포함되어야 할 최소한의 요소를 권고하였다. 아울러 UMI, OULS, UBCL, USL 등 선진 대학도서관의 최근 전략적 계획 문서의 사례를 통하여 사명과 비전, 전략 등의 내용을 구체적으로 제시하였다. 궁극적으로 본 연구는 아직 전략적 계획의 작성이 일반화되지 않은 우리나라 대학도서관에 전략적 계획 수립을 위한 방향 제시와 기초 자료를 제공하고자 하였다.