• Title/Summary/Keyword: USL

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

  • Lee, Seo Jeong;Cha, Kyoon Ho
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.3
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    • pp.315-330
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    • 2018
  • A subcritical facility must ensure nuclear criticality safety under all circumstances. For this purpose, it is essential to have a procedure to validate that calculated values do not exceed upper subcritical limit (USL), determined by quantifying the bias and uncertainty. However, there are several validation methodologies of nuclear criticality safety and these can yield different USL. Therefore, it is necessary to analyze the validity of the methodologies to establish one methodology that can provide the most appropriate USL. In this study, two documents, a guide for validation of nuclear criticality safety calculational methodology (NUREG/CR-6698) and a criticality benchmark guide for light water reactor fuel in transport and storage package (NUREG/CR-6361), are compared and analyzed. In particular, the methodology in NUREG/CR-6361 is applied to the USLSTATS code. However, the analysis results show that the methodology in NUREG/CR-6698 is more appropriate, for several reasons. This is applied to decision of USL to design casks using SCALE code version 6.1.

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

  • 이상호;안동규;최홍석;양동열;문영복;채희창
    • Korean Journal of Computational Design and Engineering
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    • v.7 no.3
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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.

Recognition Performance Improvement of Unsupervised Limabeam Algorithm using Post Filtering Technique

  • Nguyen, Dinh Cuong;Choi, Suk-Nam;Chung, Hyun-Yeol
    • IEMEK Journal of Embedded Systems and Applications
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    • v.8 no.4
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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.

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

  • Park, Young-Ho;Kim, Ki-Hyun;Moon, Sang-Jae;Gang, Shin-Gak
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.5 no.1
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    • pp.65-84
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    • 1995
  • The information security is needed to guarantee the safety and the confidence to users in open system. This paper analyzes transport layer security protocol and security association protocol, which are standards proposed by ISO/IEC, to provide a security service in the transport layer and particulars, not in the standard, are defined for development. And this paper suggests a development model and develps security system based upon the suggested model. The ONP of USL is used as the development environment.

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

  • 박영호;이국희;문상재
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.4
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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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The development of security system for OSI transport layer (OSI 트랜스포트 계층을 위한 보호 시스템의 개발)

  • 김기현;박영호;문상재;박정수;신명기;강신각
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 1994.11a
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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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Rapid Fabrication of Large-Sized Solid Shape using 3D Scanner and Variable Lamination Manufacturing : Case Study of Mount Rushmore Memorial (삼차원 스캐너와 가변 적층 쾌속조형공정을 이용한 대형 입체 형상의 쾌속 제작 : 러쉬모어산 기념물 제작 사례)

  • 이상호;김효찬;송민섭;박승교;양동열
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.12
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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.

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

  • Cho, Yoon-Hee
    • Journal of the Korean Society for information Management
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    • v.22 no.4 s.58
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    • pp.111-128
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    • 2005
  • University libraries have been facing challenges to accomplish both roles of traditional libraries as physical places and virtual libraries which service electronic resources effectively. University libraries need to establish a strategic plan as a positive tool for designing the future of university libraries addressing threats and opportunities at the same time. This study suggested the core elements be involved in strategic plans of university libraries through comparatively analyzing the actual documents of strategic plans of academic libraries in America, England, Canada and Australia. These strategic plans were divided into formal elements and content elements. In addition, this study presented the latest strategic plans of academic libraries such as UMI. OULS, UBCL, and USL. As a result of research, this study provided the directions and basic materials in order to establish strategic planning at university libraries in Korea.

A Study on the Heat Mechanism of Electrolytic Capacitor and Burnout Pattern Analysis (전해 커패시터의 발열 메커니즘 및 소손 패턴 해석)

  • Choi, Chung-Seog;Park, Hyung-Ki
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2011.11a
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    • pp.40-43
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    • 2011
  • 전해 커패시터의 발열 메커니즘 및 소손 패턴 해석에서 최초의 출화는 1차측 전원으로 확인되었다. 전해 커패시터 외부의 방폭캡이 탄화되었고, 인접한 기판에도 탄화된 흔적을 확인되었으나 극성의 역사용, 과전압의 인가 및 금속한 충전 및 방전 등은 없었다. 전해 커패시터 내부를 X-ray 분석한 결과 전극 및 극판에는 이상이 없는 것으로 확인되었다. 부품 사양에 제시된 하한사양한계(LSL)는 144[${\mu}F$], 상한사양한계(USL)는 216[${\mu}F$]이며, 소손된 전해 커패시터의 공정능력분포(Cpk)가 1.21로 분석된 것으로 보아 공정 개선이 필요한 것으로 판단된다. 전해커패시터의 발열 메커니즘은 AC 과전압의 인가, 서지의 유입, 내부 온도의 상승, 기밀불량 등에 의해 지배되는 것을 알 수 있었다. 전해 커패시터를 설계할 때 고려사항은 적절한 전압의 인가, 정확한 등가직렬저항(ESR)의 연결, 급속한 충전 및 방전의 제어, 충분한 유전정접의 여유(margin) 확보 등이 중요한 요소이다.

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