• 제목/요약/키워드: Operation key

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모델기반 시스템공학을 응용한 대형복합기술 시스템 개발 (Application of Model-Based Systems Engineering to Large-Scale Multi-Disciplinary Systems Development)

  • 박중용;박영원
    • 제어로봇시스템학회논문지
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    • 제7권8호
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    • pp.689-696
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    • 2001
  • Large-scale Multi-disciplinary Systems(LMS) such as transportation, aerospace, defense etc. are complex systems in which there are many subsystems, interfaces, functions and demanding performance requirements. Because many contractors participate in the development, it is necessary to apply methods of sharing common objectives and communicating design status effectively among all of the stakeholders. The processes and methods of systems engineering which includes system requirement analysis; functional analysis; architecting; system analysis; interface control; and system specification development provide a success-oriented disciplined approach to the project. This paper shows not only the methodology and the results of model-based systems engineering to Automated Guided Transit(AGT) system as one of LMS systems, but also propose the extension of the model-based tool to help manage a project by linking WBS (Work Breakdown Structure), work organization, and PBS (Product Breakdown Structure). In performing the model-based functional analysis, the focus was on the operation concept of an example rail system at the top-level and the propulsion/braking function, a key function of the modern automated rail system. The model-based behavior analysis approach that applies a discrete-event simulation method facilitates the system functional definition and the test and verification activities. The first application of computer-aided tool, RDD-100, in the railway industry demonstrates the capability to model product design knowledge and decisions concerning key issues such as the rationale for architecting the top-level system. The model-based product design knowledge will be essential in integrating the follow-on life-cycle phase activities. production through operation and support, over the life of the AGT system. Additionally, when a new generation train system is required, the reuse of the model-based database can increase the system design productivity and effectiveness significantly.

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A Study on Maritime Trade between Korea, China and Japan in the CheongHaeJin of the 9th Century

  • 한낙현;박명섭;김병조
    • 무역상무연구
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    • 제34권
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    • pp.109-131
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    • 2007
  • This paper has focusing CheongHaeJin's maritime trading activities between Korea, China and Japan in the 9th century. In operation of CheongHaeJin which Chang BoGo was given a key role, CheongHaeJin creates three nation's wealth in triangular trade among Korea, China and Japan. And also, CheongHaeJin's contribution is considerable to the maritime trade development of Northeast Asia through establishing trading advance base in China and Japan, and organizing Shilla's people in China. Chang BoGo justified the control over small business groups of the west and south sea of Korea and the east and south sea of China by keeping pirates away His trade groups controlled foreign trade of three countries: Shilla, the Dang Dynasty of China and Japan. They connected Persia, India, Southeast Asia, and China. CheongHaeJin's key success factors of the maritime activities are summarized as follows; There is a possibility of searching that successful factor from the people of operator of CheongHaeJin. Based on oceanic adventurous spirit with character and progressive thinking could complete the rally of sea influence and composition of fleets. Secondly, the success factor is the excellent operational ability and leadership which learned in the Dang Dynasty of China. Thirdly, In 9th century, International political context was suitable for CheongHaeJin's construction and operation. Such political circumstances had given to CheongHaeJin remunerative position. Finally, Although central government could not maintain the sea traffic securities, Chang BoGo's ocean trading fleets guaranteed the safe fishing industry of people and security of sea traffic.

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우리나라의 차세대 자유비행 인프라구축 전략에 관한 연구 (A Study for Master plan of Infrastructure Establishment of Next Generation Free Flight Concept)

  • 한재현;김장환;강자영
    • 한국항공운항학회지
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    • 제16권4호
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    • pp.54-62
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    • 2008
  • International organizations related to air transport such as ICAO, IATA, ACI are forecasting that the number of passenger will grow about 4.4% annually up to 2015. Therefore, the innovation of given system technology and operation procedure is required in global scale to cope with the increase of air traffic demand. CNS/ATM infrastructure based on satellite is considered to play key role in order to solve the problems due to the dramatic increase of air traffic demand over the world. Free flight concept in the air transport operation has been proved with CNS/ATM infrastructure especially in USA and Europe. Therefore, it is necessary to develop key technologies to overcome technology gap and to secure international competitiveness in Korea. ADS-B is an important issue, and new element technologies should be considered as essential items which were shown in Capstone project. Nowadays, the free flight concept is combined to Air Transport Road Map such as NextGen project in USA, SESAR in Europe. In this process, free flight is included in the concepts such as ATM(Air Traffic Management), aviation security and safety, environmental protection and economy development, wide area weather variable reduction service, information integration and application between the related authorities (civil/military) etc. The purpose of research is to establish mid-term and long-term infrastructure plan and strategy for free flight realization in Korea. The analysis of action target and equipment construction status, phase construction plan of infrastructure has been performed by considering mid-term and long-term free flight plans of USA and Europe.

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고비도 RSA 프로세서에 적용 가능한 효율적인 누적곱셈 연산기 (An Efficient MAC Unit for High-Security RSA Cryptoprocessors)

  • 문상국
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2007년도 춘계종합학술대회
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    • pp.778-781
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    • 2007
  • 1024비트 이상의 고비도 RSA 프로세서에서는 몽고메리 알고리즘을 효율적으로 처리하기 위하여 전체 키 스트림을 정해진 블록 단위로 처리한다. 본 논문에서 기본으로 하는 RSA 프로세서는 기본 워드를 128비트로 하고 곱셈 결과의 누적기로는 256비트의 레지스터를 사용한다. 128 비트 곱셈을 효율적으로 수행하기 위하여 32비트 * 32비트 곱셈기를 사용하며 각 연산 결과는 128비트 크기의 8개 레지스터에 필요에 따라 저장되어 몽고메리 알고리즘을 수행하는데 사용된다. 본 논문에서는 128 비트 곱셈에 필요한 누적곱셈 (MAC; multiply-and-aCcumultaion)을 효율적으로 계산하기 위하여 모든 연산 단계를 미리 분석하여 불필요한 연산단계를 수행하지 않고 곱셈 횟수를 줄여 효율적인 누적곱셈 연산기를 구현하였다. 구현된 누적곱셈 연산기는 자동으로 합성하였고, 본 논문 작성에서 기준이 되는 RSA 프로세서의 동작 주파수인 20MHz에서 정상적으로 동작하였다.

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OECD/NEA BENCHMARK FOR UNCERTAINTY ANALYSIS IN MODELING (UAM) FOR LWRS - SUMMARY AND DISCUSSION OF NEUTRONICS CASES (PHASE I)

  • Bratton, Ryan N.;Avramova, M.;Ivanov, K.
    • Nuclear Engineering and Technology
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    • 제46권3호
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    • pp.313-342
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    • 2014
  • A Nuclear Energy Agency (NEA), Organization for Economic Co-operation and Development (OECD) benchmark for Uncertainty Analysis in Modeling (UAM) is defined in order to facilitate the development and validation of available uncertainty analysis and sensitivity analysis methods for best-estimate Light water Reactor (LWR) design and safety calculations. The benchmark has been named the OECD/NEA UAM-LWR benchmark, and has been divided into three phases each of which focuses on a different portion of the uncertainty propagation in LWR multi-physics and multi-scale analysis. Several different reactor cases are modeled at various phases of a reactor calculation. This paper discusses Phase I, known as the "Neutronics Phase", which is devoted mostly to the propagation of nuclear data (cross-section) uncertainty throughout steady-state stand-alone neutronics core calculations. Three reactor systems (for which design, operation and measured data are available) are rigorously studied in this benchmark: Peach Bottom Unit 2 BWR, Three Mile Island Unit 1 PWR, and VVER-1000 Kozloduy-6/Kalinin-3. Additional measured data is analyzed such as the KRITZ LEU criticality experiments and the SNEAK-7A and 7B experiments of the Karlsruhe Fast Critical Facility. Analyzed results include the top five neutron-nuclide reactions, which contribute the most to the prediction uncertainty in keff, as well as the uncertainty in key parameters of neutronics analysis such as microscopic and macroscopic cross-sections, six-group decay constants, assembly discontinuity factors, and axial and radial core power distributions. Conclusions are drawn regarding where further studies should be done to reduce uncertainties in key nuclide reaction uncertainties (i.e.: $^{238}U$ radiative capture and inelastic scattering (n, n') as well as the average number of neutrons released per fission event of $^{239}Pu$).

산업설비 기술수준 평가를 통한 주요업무 도출 및 모델 구축방안 연구 (Establishment of Critical Work Models through the Evaluation of Technology Competitiveness)

  • 박수현;하승호;김경민;박찬혁;김경주
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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    • pp.526-530
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    • 2004
  • 산업설비 분야는 건설 산업의 고도화에 따라 산업시설의 비중이 증대되고 있으며, 첨단기술의 접목을 통한 고부가 가치를 창출할 수 있는 역동적인 분야임에도 단계별 정보 흐름의 관리와 지식 집약적인 업무 수행이 미흡한 실정이다. 향후 국제 산업설비 시장에서 건설 프로젝트 수요증대, 유지관리 분야의 확대가 예상되며, 이에 대응하여 국내에서는 지속적인 설계기술 및 노하우 축적이 시급하다. 본 연구에서는 국내 산업설비의 미흡한 부분을 객관적으로 파악하고, 주요 단계의 업무 모델을 제시하기 위하여 국내 산업설비 현행 업무프로세스로부터 프로젝트 관리 핵심요소를 도출하였다. 이를 해외 산업설비 수준과 비교해 봄으로써 국내공사 기술수준을 파악하고, 산업설비 주요 업무단계에 대한 업무모델을 구축하여 향후 개선된 업무모델을 제시하고자 한다.

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공개키 암호시스템의 처리속도향상을 위한 모듈러 승산기 설계에 관한 연구 (A Study of the Modulus Multiplier Design for Speed up Throughput in the Public-key Cryptosystem)

  • 이선근;김환용
    • 대한전자공학회논문지SD
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    • 제40권4호
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    • pp.51-57
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    • 2003
  • 통신망 및 그 이외의 네트워크 환경의 발전은 사회적으로 중요한 문제를 발생시켰다. 이러한 문제점 중 가장 중요한 것이 네트워크 보안 문제이다. 보안과 관련된 문제점들은 해킹, 크랙킹과 같은 방법으로 반 보안 분야를 확장시키며 발전되었다. 새로운 암호 알고리즘의 발달 없이 해커나 크래커로부터 데이터를 보호하기 위해서는 기존과 같이 키의 길이를 증대하거나 처리 데이터의 양을 증대시키는 방법 밖에는 없다. 본 논문에서는 공개키 암호 알고리즘의 몽고메리 승산부에서 처리속도를 감소시키기 위한 M3 알고리즘을 제안하였다. 매트릭스 함수 M(·)과 룩업테이블을 사용하는 제안된 M3 알고리즘은 몽고메리 승산부의 반복 연산부를 선택적으로 수행하게 된다. 이러한 결과로 변형된 반복 변환 부분은 기존 몽고메리 승산기에 비하여 30%의 처리율 향상을 가져왔다. 제안된 몽고메리 승산 M3 알고리즘은 캐리 생성부의 어레이 배열과 가변 길이 오퍼랜드 감소로 인한 병목 현상을 줄일 수 있다. 그러므로 본 논문에서는 제안된 M3 알고리즘을 공개키 암호시스템의 대표적인 시스템인 RSA에 적용하여 M3-RSA를 설계하였으며 설계 및 모의실험은 Synopsys ver 1999.10을 사용하였다. M3 알고리즘은 기존 승산알고리즘에 비하여 30%의 처리속도 증가를 보임으로서 크랙 및 처리율 향상에 영향이 많은 공개키 암호시스템에 적합하리라 사료된다.

The Role of Charge and Retention in Effective Wet end Management

  • Rantala, T.;Nokelainen J.;Ojala, T;Dr. Taina Sopenlehto
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2000년도 제26회 펄프종이기술 국제세미나
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    • pp.1-10
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    • 2000
  • The development of paper machines, increasing machine speeds with new, mostly low basis weight and/or high ash content paper grades, as well as the fact that several trends regarding process items have increased the sensitivity of papermaking. At the same time, papermakers are looking for flexibility in the production line. We can say that with all PMs the biggest benefits with the lowest capital spending can be achieved by focusing on improved wet end management. In order to manage wet end chemistry on a paper machine, our goal is to control sub-process through which we can influence the operation of the entire wet end with maximum effect. Key measurements and controls are-white water consistency control which is the most effective way to control retention - charge demand measurement and control which takes care of concentration of the anionic material entering to PM -ash measurements and controls which are deeply related to retention and paper quality This paper presents and concentrates to two of these key controls ; retention and charge. The purpose of charge control is to give the process control the tools to react to changes caused by amount of dissolved and colloida material incoming to wet end system. It is called coagulation or fixing control. Retention control is then taking care of retention aid flow to the process by responding any changes seen in white water consistency. It is called flocculation control. Each of these solutions separately , and even more effectively all together, stabilize the wet end operations and so greatly improve the produced paper quality and machine runnability. Practical results will be presented and they are referring to the latest mill cases. We have developed the first wet end measuring system in the late 1980s and control solutions based on this modern measuring technology were completely updated in 1990s. This paper introduces the principle, operation , and results of our unique wet end analyzers (retention and charge ) which are at the level of automation solutions as a part of paper machine quality control Especially our newest member of the platform , on-line charge analyzer has reached and set new standards to the on-line charge monitoring.

The Role of Charge and Retention in Effective Wet End Management

  • Rantala, T.;Nokelainen, J.;Ojala, T.;Sopenlehto, Taina
    • 펄프종이기술
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    • 제32권5호
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    • pp.44-53
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    • 2000
  • The development of paper machines, increasing machine speeds with new, mostly low basis weight and/or high ash content paper grades, as well as the fact that several trends regarding process items have increased the sensitivity of papermaking. At the same time, papermakers are looking for flexibility in the production line. We can say that with all PMs, the biggest benefits with the lowest capital spending can be achieved by focusing on improved wet end management. In order to manage wet end chemistry on a paper machine, our goal is to control subprocesses through which we can influence the operation of the entire wet end with maximum effect. Key measurements and controls are - white water consistency control which is the most effective way to control retention. - charge demand measurement and control which takes care of concentration of the anionic material entering to PM. - ash measurements and controls which are deeply related to retention and paper quality. This paper presents and concentrates to two of these key controls: retention and charge. The purpose of charge control is to give the process control the tools to react to changes caused by amount of dissolved and colloidal material incoming to wet end system. It is called coagulation or fixing control. Retention control is then taking care of retention aid flow to the process by responding any changes seen in white water consistency. It is called flocculation control. Each of these solutions separately, and even more effectively all together, stabilize the wet end operations and so greatly improve the produced paper quality and machine runnability. Practical results will be presented and they are referring to the latest mill cases. We have developed the first wet end measuring system in the late 1980s and control solutions based on this modern measuring technology were completely updated in 1990s. This paper introduces the principle, operation, and results of our unique wet end analyzers (retention and charge) which are at the level of automation solutions as a part of paper machine quality control. Especially our newest member of the platform, on-line charge analyzer has reached and set new standards to the on-line charge monitoring.

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RSA 암호화 프로세서에 적용 가능한 효율적인 누적곱셈 연산기 설계 (Design of an Efficient MAC Unit for RSA Cryptoprocessors)

  • 문상국
    • 한국정보통신학회논문지
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    • 제12권1호
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    • pp.65-70
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    • 2008
  • 1024비트 이상의 고비도 RSA 프로세서에서는 몽고메리 알고리즘을 효율적으로 처리하기 위하여 전체 키 스트림을 정해진 블록 단위로 처리한다. 본 논문에서 기본으로 하는 RSA프로세서는 기본 워드를 128비트로 하고 곱셈 곁과의 누적기로는 256비트의 레지스터를 사용한다. 128 비트 곱셈을 효율적으로 수행하기 위하여 32비트${\times}$32비트 곱셈기를 사용하며 각 연산 결과는 128비트 크기의 8개 레지스터에 필요에 따라 저장되어 몽고메리 알고리즘을 수행하는데 사용된다. 본 논문에서는 128비트 곱셈에 필요한 누적곱셈 (MAC; multiply-and-aCcumultaion)을 효율적으로 계산하기 위하여 모든 연산 단계를 미리 분석하여 불필요한 연산단계를 수행하지 않고 곱셈 횟수를 줄여 효율적인 누적 곱셈 연산기를 구현하였다. 구현된 누적 곱셈 연산기는 자동으로 합성하였고, 본 논문 작성에서 기준이 되는 RSA프로세서의 동작 주파수인 20MHz에서 정상적으로 동작하였다