• 대한조선학회논문집
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• 제55권4호
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• pp.341-349
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• 2018

Recently, it has been reported that the whipping response, which is the elastic phenomenon of the ship, may be one of the causes of the ship accident. Unfortunately, the commonly used methodology for evaluating the whipping effect effectively has not been developed yet. In this study, we developed a procedure to estimate the whipping effect of hull in actual design stage. Fluid-structure interaction analysis was performed for a dominant short term sea state to obtain the time series data of vertical wave bending moment including the whipping response by slamming. In order to estimate the whipping effect by using the time series, some signal processing and statistical techniques such as low pass filtering, Weibull fitting and so on, were applied. the hydro-elasticity analysis was performed on container ships of various sizes to evaluate the whipping effect. The parameters that can affect the response of the hull vibration was selected and the effect of these parameters on whipping was analyzed.

• ETRI Journal
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• 제36권2호
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• pp.321-324
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• 2014

This letter describes a two-phase clock oxide thin-film transistor shift register that executes a robust operation over a wide threshold voltage range and clock coupling noises. The proposed circuit employs an additional Q generation block to avoid the clock coupling noise effects. A SMART-SPICE simulation shows that the stable shift register operation is established for the clock coupling noises and the threshold voltage variation from -4 V to 5 V at a line time of $5{\mu}s$. The magnitude of coupling noises on the Q(15) node and Qb(15) node of the 15th stage is respectively -12.6 dB and -26.1 dB at 100 kHz in the proposed circuit, compared to 6.8 dB and 10.9 dB in a conventional one. In addition, the estimated power consumption is 1.74 mW for the proposed 16-stage shift registers at $V_{TH}=-1.56V$, compared to 11.5 mW for the conventional circuits.

• 한국정밀공학회지
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• 제31권8호
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• pp.653-658
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• 2014

Roll-to-Roll printing process has become a great issue as a breakthrough for low cost and mass production of electronic devices such as organic thin film transistor, and etc. To print the electronic devices, multi-layer printing is essential, and high precision register control is required for this process. Unlike stop-and-repeat printing process, it is impossible to control the register in a static state since the roll-to-roll process is a continuous system. Therefore, the behavior of web such as polyethylene terephthalate (PET) and polyimide (PI) by the tensile and thermal stress generated in the roll-to-roll process as well as motor control of driven rolls has to be considered for a high precision register control. In this study, the correlation between curing temperature and thermal deformation of PET web is analyzed. Finally, it is verified experimentally that the temperature disturbance generates the more serious register error under the higher curing temperature.

• 한국해양공학회지
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• 제28권2호
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• pp.147-151
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• 2014

This research presents a method for the initial structural design of a multi-megawatt wind turbine blade. The structural data for a 2-MW blade were applied as the blade structural characteristic data of the reference blade. Tenkinds of blade models were newly designed by replacing the spar cap axial GRRP with a GFRP and CFRP These terms should be defined. at different orientations. The axial stiffness coefficients of the newly designed models were made equal to the coefficient of the reference blade. The required numbers of layers in each section of blades were calculated, and the lay-up designs were based on these numbers. Verification results showed that the design method that used the structural data of the reference blade was appropriate for the initial structural design of a wind turbine blade.

• 한국통신학회논문지
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• 제29권1C호
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• pp.166-174
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• 2004

대리서명은 원서명자가 자신의 서명 권한을 대리 서명자에게 위임하여 대리 서명자가 원서명자를 대신해서 서명을 생성하는 것을 말한다. 대리서명은 원서명자가 위임 정보에 대한 서명을 생성하고 이를 위임자에게 전달하여 위임자가 위임키로서 사용하게 하는 것이다. 본 논문에서는 원서명자와 대리서명자가 기존의 인증서를 발급 받은 환경에서 원서명자가 대리서명자에 대하여 검증자에계 위임정보를 등록하는 프로토콜을 제안한다. 위임내용에 대해 원서명자가 디지털 서명을 하고 검증자는 이에 해당하는 내용을 검증한 후 위임서명자에 대한 권한, 기간 등의 제약사항을 설정하고 허가된 범위 내에서 위임 서명을 한다.

• 대한후두음성언어의학회지
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• 제13권2호
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• pp.151-154
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• 2002

Background and Objectives : The pitch range of the human voice is variable, extending from chest register to falsetto register. Although numerous studies have investigated after laryngeal mechanism description of falsetto tone, systematic and objective studies were lack. The purpose of this study was to systematically analyze and compare modal with falsetto voice. Materials and Methods : Seven adult baritones were selected from a larger population of volunteers at choir. Simultaneous measurements of acoustic, electroglottographic and aerodynamic study were made during /e/ sustained in two vocal registers, lowest modal and highest falsetto. Statistical analysis was performed using Wilkoxson signed rankes test. Results : In the acoustic analysis, shimmer was increased in flasetto voice(p<0.05). In the electroglottographic analysis, closed quotient(CQ), speed quotient(SQ) at the modal voice were higher than at the falsetto voice(p<0.05). In the aerodynamic analysis, and airflow rate(MFR) of falsetto voice was higher than modal voice(p<0.05). Conclusions : In the results of the study indicate that, falsetto register ineffective, inefficient, generally unpleasant because it was produced by incomplete clousure of true vocal cord. We anticipated that further study with large samples can provide an objective criteria for status and classification of singer's modal and falsetto voice.

• Progress in Superconductivity
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• 제1권1호
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• pp.31-35
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• 1999

We have fabricated and tested a simple circuit of the rapid single-flux-quantum(RSFQ) four-stage shift register using a single layer high-$T_c$ superconducting (HTS) $YBa_2Cu_3O_{7-x}$ (YBCO) thin film structure with 9 step-edge Josephson junctions. The circuit includes two read superconducting quantum interference devices(SQUID) and four stages. To establish a robust HTS RSFQ device fabrication process, we have focussed on the reproducible process of sharp and straight step-edge formation as well as the ratio of film thickness to step height, t/h. The spread of step-edge junction parameters was measured from each 13 junctions with t/h=1/3, 1/2, and 2/3 at various temperatures. We have demonstrated the simplified operation of the shift register at 65 K.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.146-149
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• 2001

인터넷 상에서 SIP을 사용한 VoIP 서비스를 제공하기 위해서는 사용자의 위치 정보 추적 및 Call의 적절한 전달을 위한 사용자의 현재 위치에 대한 정보를 Registrarar 서버에 등록을 해야 한다. SIP의 REGISTER 메시지를 사용하여 사용자의 SIP URI 주소와 하나 이상의 현재 접근 가능한 주소를 등록을 하게되며, 이때 등록되는 주소는 SIUP URI에만 제한된 것이 아니라 mailto, http, tel 등 여러 스킴을 등록할 수 있다. 사용자의 위치 정보 들고의 과정에서는 인증에 대한 고려가 필수적으로 이루어져야 한다. 본 논문에서는 이 과정에서 이루어지는 서버와 클라이언트간의 트랜스액션에 대한 내용과 제 3자에 의한 등록 기능을 가능토록 하게 하기 위한 서버측에서의 고려사항과 이를 지원하기 위한 서버의 기능 설계에 대한 내용을 다루도록 하겠다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제5권1호
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• pp.47-61
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• 2013

This study compares the Residual ultimate longitudinal strength - grounding Damage index (R-D) diagrams produced by two analysis methods: the ALPS/HULL Intelligent Supersize Finite Element Method (ISFEM) and the design formula (modified Paik and Mansour) method - used to assess the safety of damaged ships. The comparison includes four types of double-hull oil tankers: Panamax, Aframax, Suezmax and VLCC. The R-D diagrams were calculated for a series of 50 grounding scenarios. The diagrams were efficiently sampled using the Latin Hypercube Sampling (LHS) technique and comprehensively analysed based on ship size. Finally, the two methods were compared by statistically analysing the differences between their grounding damage indices and ultimate longitudinal strength predictions. The findings provide a useful example of how to apply the ultimate longitudinal strength analysis method to grounded ships.

• 한국정보처리학회논문지
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• 제6권2호
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• pp.497-511
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• 1999

최근 많은 명령어 수준 병렬 처리 기술들이 개발되면서 ILP 프로세서 성능이 급격히 증가하고 있다. 특히, 새로운 기술로 주목 받고 있는 EPIC(Explicitly Parallel Instruction Computing) 아키텍쳐는 조건실행 (Predicated Execution)과 투기적실행(Speculative execution)을 하드웨어와 접목하여 성능 향상을 시도하고 있다. 본 논문에서는 EPIC 아키텍쳐의 특성을 최대로 활용하여 코드 스케줄 가능성을 높이는 새로운 레지스터 할당 알고리듬을 제안한다. 그리고, 제안된 레지스터 할당 알고리듬은 조건실행의 적용으로 인하여 더욱 효율을 높일 수 있음을 실험을 통하여 입증한다. 실험 결과 기존의 레지스터 할당 방법에 비하여 평균 19%의 성능 향상을 보임으로써 제안된 레지스터 할당 방법이 효과적임을 검증한다.