• 제목/요약/키워드: scheme of the committee

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자유표면시뮬레이션의 TOUD 연구 (Study on the Third-Order-Upwind-Difference(TOUD) for the Free-Surface Simulation)

  • 곽승현
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.154-159
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    • 2004
  • A new finite difference scheme is studied fur the simulation of free surface, surface the third derivative tenn for the wave elevation is artificially added in the the free-surface boundary condition. This study presents a comparative analysis with simulations performed by using the classical MAC method. More systematic computations are carried out by changing the submergence depth and angle of attack. Through the numerical simulation, it is found that a new numerical method becomes more efficient for the reason that the free surface elevation is reasonably developed at tire rear of trailing edge.

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스테인리스강의 크리프 특성치와 파단시간과의 관계 (Relationship between Creep Characteristic Values and Rupture time in STS304 Stainless Steels)

  • 공유식;김선진;이배섭
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.228-233
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    • 2004
  • The characteristics of the probability distribution for mechanical properties, e.g. tensile strength, reduction of area ana elongation, for STS304 stainless steel in elevated temperature were investigated from tensile test performed by constant cross head speea controls with 1mm/min, Recently, in order to clarify the strengthening mechanisms at high temperature, a new scheme to improve high temperature mechanical properties is desired. Therefore, the test ,technique development of high temperature creep behaviors for this material is very important. In this paper, the creep praperties and creep life prediction by Larson-Miller parameter method for STS304 stainless steel to be used for other high temperature components were presented at the elevated temperatures of 600, 650 and $700^{\circ}C$.

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2차원 유체-구조물-지반계의 지진응답해석 (Earthquake Response Analysis for 2-D Fluid-Structure-Soil Systems)

  • 윤정방;장수혁;김재민
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2001년도 추계학술대회 논문집
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    • pp.132-137
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    • 2001
  • This paper presents a method of seismic analysis for a 2-D fluid-structure-soil interaction systems. With this method, the fluid can be modeled by spurious free 4-node displacement-based fluid elements which use rotational penalty and mass projection technique in conjunction with the one point reduced integration scheme to remove the spurious zero energy modes. The structure and the near-field soil are discretized by the standard 2-D finite elements, while the unbounded far-field soil is represented by the dynamic infinite elements in the frequency domain. Since this method directly models the fluid-structure-soil interaction systems, it can be applied to the dynamic analysis of a 2-D liquid storage structure with complex geometry. Finally, results of seismic analyses are presented for a spent fuel storage tank embedded in a layered half-space and a massive concrete dam on a layered half-space.

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External Quality Assessment Scheme for Biological Monitoring of Occupational Exposure to Toxic Chemicals

  • Lee, Mi-Young;Yang, Jeong-Sun;Kang, Seong-Kyu
    • Safety and Health at Work
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    • 제2권3호
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    • pp.229-235
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    • 2011
  • Objectives: In this study, we summarized the External Quality Assessment Scheme (EQAS) for the biological monitoring of occupational exposure to toxic chemicals which started in 1995 and continued until a $31^{st}$ round robin in the spring of 2010. The program was performed twice per year until 2009, and this was changed to once a year since 2010. The objective of the program is to ensure the reliability of the data related to biological monitoring from analytical laboratories. Methods: One hundred and eighteen laboratories participated in the $31^{st}$ round robin. The program offers 5 items for inorganic analysis: lead in blood, cadmium in blood, manganese in blood, cadmium in urine, and mercury in urine. It also offers 10 items for organic analysis, including hippuric acid, methylhippuric acid, mandelic acid, phenylglyoxylic acid, N-methylformamide, N-methylacetamide, trichloroacetic acid, total trichloro-compounds, trans,trans-muconic acid, and 2,5-hexanedione in urine. Target values were determined by statistical analysis using consensus values. All the data, such as chromatograms and calibration curves, were reviewed by the committee. Results: The proficiency rate was below 70% prior to the first round robin and improved to over 90% for common items, such as PbB and HA, while those for other items still remained in the range of 60-90% and need to be improved up to 90%. Conclusion: The EQAS has taken a primary role in improving the reliability of analytical data. A total quality assurance scheme is suggested, including the validation of technical documentation for the whole analytical procedure.

다중 재난 상황에 적합한 COSPAS-SARSAT 탐색구조 비컨 위치추정 기법 (Beacon Geolocation Scheme of COSPAS-SARSAT System for Heavy Disaster Environment)

  • 김재현;이상욱;신천식;안우근
    • 한국위성정보통신학회논문지
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    • 제10권4호
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    • pp.146-150
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    • 2015
  • COSPAS-SARSAT 위원회에서는 2000년 이후부터 새롭게 발사되는 미국, EU, 러시아의 중궤도 항법위성에 탐색구조 탑재체를 탑재하여 중궤도 탐색구조(MEOSAR) 서비스를 제공키로 결정하였다. 비컨에서 송출되는 조난신호는 비컨 상공의 각 위성들에 각기 다른 도달시간과 도플러 주파수를 가지고 도달하며, 이를 바로 중궤도 수신국(MEOLUT)으로 전달한다. 중궤도 수신국에서는 적어도 3~4개의 위성을 동시에 추적하여 조난신호를 전달받고, 조난신호 간 TDOA(Time Difference of Arrival)와 FDOA(Frequency Difference of Arrival)를 이용하여 비컨의 위치를 추정한다. 그러나 비컨은 임의의 시간에 50초 간격으로 조난신호를 송출하므로, 대형 조난상황에서 비컨 신호가 겹치는 현상이 나타날 수 있고, 겹쳐진 비컨 신호들을 COSPAS-SARSAT에서 개발하고 있는 현재 방식으로 모든 비컨 위치를 추정하는 것은 어렵다. 따라서 여기에서는 이를 해결하기 위한 방안으로 CAF MAP 알고리즘을 소개하고, COSPAS-SARSAT 시스템의 성능 요구사항을 만족시킬 수 있도록 MCAF MAP 기법을 제안하고, 그 성능을 나타낸다.

시간영역에서 초대형 부유식 해양구조물에 대한 유탄성 운동해석 (Hydroelastic Responses of a Very Large Floating Structure in Time Domain)

  • 이호영;신현경
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 춘계학술대회 논문집
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    • pp.18-22
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    • 2000
  • This paper is transient motions of a very large floating structure subjected to dynamic load induced by wave. A time domain method is applied to the hydroelasticity problems for this purpose. The method is based on source-dipole and FEM scheme and on Newmark $\beta$ method to pursuit time step process taking advantage of the memory effect. The present method is appied to hydroelastic response analysis in regular waves and impact responses due to dropping aircraft.

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차세대 지상파 DTV 전송시스템을 위한 Enhanced-TCM CODEC 개발 (Enhanced-TCM CODEC Development for Next Generation Terrestrial DTV Transmission System)

  • 김성훈;지금란;이재영;김승원;이수인;김창중;이호경
    • 방송공학회논문지
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    • 제10권1호
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    • pp.14-21
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    • 2005
  • 본 논문은 보행/이동수신 환경에서 기존의 ATSC(Advanced Television System Committee) 8-VSB DTV 전송규격의 수신성능을 개선한 Enhanced-xVSB를 제안한다. E-xVSB시스템은 normal(8-VSB) 스트림과 enhanced(robust) 스트림을 섞어 전송하며. robust 스트림은 기존의 8-VSB 스트림인 normal stream에 비해 모드에 따라 TOY(Threshold Of Visibility)를 만족하는 SNR을 획기적으로 개선시킬 수 있으며. 이와 같은 robust 스트림은 E-xVSB 전용수신기가 아닌 기존 수신기에서는 MPEG 스트림 역다중화 과정에서 누락되어지므로 기존의 8-VSB 수신기와 하위호환성을 유지한다. E-xVSB는 이동 및 보행수신 성능개선을 위해 reduced constellation 및 enhanced trellis coded modulation기법을 도입하였으며. 사용목적에 따라 Pseudo-2VSB. Enahnced-4VSB. Enhanced-xVSB 및 Hybrid 모드등 다양한 변조기법을 지원한다.

지상파 UHD 방송 MMT/ROUTE기반 브로드밴드 콘텐츠 삽입 기술 (Broadband Content Insertion Technology based on Terrestrial UHD Broadcasting MMT/ROUTE)

  • 김두환;이동관;김규헌
    • 방송공학회논문지
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    • 제24권2호
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    • pp.329-340
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    • 2019
  • 최근 국내 지상파 UHD(Ultra-High Definition) 방송과 같은 고품질 AV(Audio-Video) 서비스가 증가하면서 그에 맞춰 방송 기술도 진화하게 되면서 방송 표준 또한 새롭게 정의하게 되었다. 또한, 네트워크 기술이 발달함에 따라, 콘텐츠가 해당 나라뿐 아니라 세계적으로 소비되고 있다. 그에 맞춰 국가 및 지역적 환경 등에 맞춰 적합한 콘텐츠를 제공하는 방안인 콘텐츠 삽입 기술이 필요할 것으로 보인다. 본 논문은 지상파 UHD 방송의 전송 표준 DASH(Dynamic Adaptive Streaming over HTTP)/ROUTE(Real time Object delivery Over Unidirectional Transport) 및 MMT(MPEG Media Transport)를 기반으로 방송망과 통신망의 이종 망 환경 하에 ATSC (Advanced Television Systems Committee) 3.0 Event Signaling 표준을 활용한 콘텐츠 삽입 서비스 시스템 모델 및 동기화 방안을 제안한다. 또한, 해당 서비스가 방송 표준을 만족하는 환경에서 동작함을 검증한다.

임대차 분쟁의 조정과 중재에 관한 연구 (A Study on the Mediation and Arbitration of Lease Dispute)

  • 남선모
    • 한국중재학회지:중재연구
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    • 제25권4호
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    • pp.119-136
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    • 2015
  • The contracting parties must be provided a litigation scheme in order to resolve a dispute. This means taking advantage of effective measures for mediation or arbitration. A lease transaction is likely to occur mainly after a dispute. It is necessary to take the appropriate measures in advance. In general, when a variety of contracts are created, conflicts arise and disputes have to be resolved through mediation and arbitration documents, and adjustment or intervention is called for. Arbitration system is a system that is established based on the trust of the arbitral tribunal. For such system, quality education for enhancing professionalism required of the arbitrator is important. A party responding to an arbitration agreement presents a problem. The current system must ensure that there are no disadvantaged parties. However, a party must depend on an arbitration agreement that is part of the law rescue system. A litigation support by the local Bar Association must be carried out. It should be notified of the contents of the contract to select a strategy that will best resolve the conflict. In the case of lease transactions, there is a need to create a scheme to make a standard agreement that inserts an arbitration clause. Lease sale and purchase agreement or lease agreement is a form of contract that has been frequently used. Here, the arbitration agreement clause for a lawyer that will serve as arbitrator should be inserted. It is a scheme that can be activated for individuals in poor areas. In addition, it is possible to see it taking a scheme to take advantage of the lawyer system for the future of the town. The Attorney System of a town is a system that the Korean Bar Association, Legal Department has put in place since 2013. If a real estate trade dispute occurs, the role of the intermediary attorney should be to carry out his duties efficiently. In the case of real estate transaction conflicts, the lawyer of the village should be registered as the arbitrator. It is important to establish a basis of regulations through this type of real estate transaction accident analysis. Before proceeding with various adjustment systems, it is desirable to expand the arbitration region. Now we need a realtor amendment. It is the part where fragmentation of intermediary qualification is required, along with the eligibility of a subdivision.

The Montreal Convention: A First Impression

  • Sekiguchi, Masao
    • 항공우주정책ㆍ법학회지
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    • 제12권
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    • pp.36-65
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    • 2000
  • The Montreal Convention markedly changed the rules governing the international carriage by air of passenger, baggage and cargo. The introduction of a considerable number of modernized major elements including electric ticketing system, the unlimited passenger liability regime and a supplementary (fifth) jurisdiction should help to remove aged scheme that now exists in the Warsaw Convention and other related instruments. The key issue of the electric ticketing system recognized by the Convention IS how to describe reasonably and adequately the terms of written notices, in the light of the principle of consumer protection. Regarding liability regime for passengers, an unlimited passenger liability regime is realized. The carrier, in the first tier, is subject to a strict liability regime of up to 100,000 SDRs, and in the second tire, a regime of presumed fault liability without numerical liability limits. To add to the present four fora, the fifth forum is permitted. Regarding damage resulting the death or injury of a passenger, an action for damages may also be brought in its home territory with the considerably qualified narrow requirements. A strange deviation from the well-established "Procedure for Approval of Draft Convention" carried out by the Legal Committee left a considerable number of unrefined and incomplete passages. In the near future, their modification should be required.

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