• Title/Summary/Keyword: 4th wave

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Design of a High-Level Synthesis System for Automatic Generation of Pipelined Datapath (파이프라인 데이터패스 자동 생성을 위한 상위수준 합성 시스템의 설계)

  • 이해동;황선영
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.31A no.3
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    • pp.53-67
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    • 1994
  • This paper describes the design of a high-level synthesis system. SODAS-VP. which automatically generates hardwares executing operation sequences in pipelined fashion.Target architecture and clocking schemes to drive pipelined datapath are determined, and the handling of pipeline hazards which degrade the performance of pipeline is considered. Partitioning of an operation into load, operation, and store stages, each of which is executed in partitiones control step, is performend. Pipelinecl hardware is generated by handling pipeline hazards with internal forwarding or delay insertion techniques in partitioning process and resolving resource conflicts among the partitioned control steps with similarity measure as a priority function in module allocation process. Experimental results show that SODAS-VP generates hardwares that execute faster than those generated by HAL and ALPS systems. SODAS-VP brings improvement in execution speed by 17.1% and 7.4% comparing with HAL and ALPS systems for a MCNC benchmark program, 5th order elliptical wave filter,respectively.

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Numerical Simulation and Analysis for Optimum Design of a Thermoacoustic Refrigerator (공명관식 열음향 냉동기의 최적설계를 위한 수치모사 및 설계인자 분석)

  • Kim, D.H.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.2
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    • pp.329-340
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    • 1995
  • Basic refrigeration effect and efficiency of a thermoacoustic refrigerator is studied. The refrigerator model for numerical simulation is composed of half wavelength resonator and appropriate stack of plate. Theoretical model for thermoacoustic refrigeration suggested by Swift et. al is adapted for numerical calculation. The model contains arbitrary viscosity effect of the gas filled in the resonator. The wave equation is integrated by using 4-th order Runge-Kutta algorithm to give pressure distribution along the stack of plate. Heat flux and COP are also calculated based on the energy flux equation. By analyzing the numerical simulation results, optimum values of design parameters for thermoacoustic refrigerator are obtained.

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Nonlinear Motion Responses of a Moored Ship beside Quay (안벽에 계류된 선박의 비선형 운동응답)

  • 이호영;임춘규;유재문;전인식
    • Journal of Ocean Engineering and Technology
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    • v.17 no.4
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    • pp.8-15
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    • 2003
  • When a typoon sets into harbour, a moored ship shows erratic motions and even mooring line failure may occur. such troubles may be caused by harbour resonance phenomena, resulting in large motion amplitudes at low frequency, which is close ti the natural frequency of th moored ship. The nonlinear motions of a ship moored to quay are simulated under external forces due to wave, current including mooring forces in time domain. The forces due to waves are obtained from source and dipole distribution method in the frequency domain. The current forces are calculated by using slow motion maneuvering equation in the horizontal plane. The wind forces are calculated from the empirical formula of ABS and the mooring forces of ropes and fenders are modeled as linear spring.

A Study on the Improvement of Penetration Capability of a Shaped Charge by Controlling the Jet Mass Parameters (제트 질량 변수 조절에 의한 성형작약 관통성능 증대 연구)

  • So, Byeongkwan
    • Journal of the Korea Institute of Military Science and Technology
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    • v.18 no.5
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    • pp.566-573
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    • 2015
  • The most important factor for the penetration performance of shaped charge is the liner design. By designing the liner to have properties of both high jet tip velocity and long jet break-up time, the better penetration performance could be acquired. Usually it is very difficult to satisfy above two conditions simultaneously. In this study, the liner with the shape of ogive was developed to have relatively larger jet mass compared to the conventional trumpet liner. The designed shaped charge showed jet properties with high jet tip velocity and long jet break-up time by using ogive liner and wave shaper. A commercially available hydro-dynamic code AUTODYN-2D was used for numerical analysis of jet formation. The flash X-ray test and the static penetration test were conducted to verify the results of numerical analysis.

A Datapath Scheduling Under Resource Constraints (자원제약조건 하에서의 데이터패스 스케듈링)

  • 이근만;임인칠
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.4
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    • pp.424-432
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    • 1992
  • This paper deals with the scheduling ploblems, which are the most important subtasks in High-level syntheses. IP(integer programming) formulations is used as the scheduling problem approach. This paper describes a new resource-constraints scheduling algorithm. We have concentrated our attentions on the multicycle operations and the structural pipelining, and we fully analyze the characteristics of operators to achieve the maximal performance and the maximal resource sharing. For experiment results, we choose the 5-th order digital wave filter as a benchmark and do the schedule, Finally, we can obtain near-optimal scheduling results.

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Moderating effect of social relationship on academic stress and psychological health (청소년의 학업스트레스와 정신건강의 관계에서 사회적 관계의 조절효과)

  • Kim, Youn-Hee;Yoo, Mi-Sook
    • Journal of Families and Better Life
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    • v.28 no.5
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    • pp.225-234
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    • 2010
  • The purpose of this study is to examine moderating effect of social relationship on the relationship between academic stress and psychological health among of adolescents. This data used in this study used data was derived from the wave 2-4(2004-2006) of Korean Youth Panel Study (KYPS). The results show that social relationship(parent-child relationship and peer relationship) had a moderating effect on academic stress and psychological health of adolescents. In short, it was verified that in the case of good social relationship, academic stress could actually buffer the effect of psychological health. However, it terms of parent-child relationship, it was not confirmed to have a moderating effect on academic stress and psychological health in the 11th grade. The results from above suggest that schools and related facilities adolescent should consider the program to reinforce social relationship and the timing of the intervention.

NUMERICAL REQUIREMENTS FOR THE SIMULATION OF DETONATION CELL STRUCTURES (기체 상 데토네이션 셀 구조 해석을 위한 수치적 요구 조건)

  • Choi, Jeong-Yeol;Cho, Deok-Rae;Lee, Su-Han
    • 한국전산유체공학회:학술대회논문집
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    • 2007.04a
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    • pp.177-181
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    • 2007
  • Present study examines the numerical issues of cell structure simulation for various regimes of detonation phenomena ranging from weakly unstable to highly unstable detonations. Inviscid fluid dynamics equations with $variable-{\gamma}$ formulation and one-step Arrhenius reaction model are solved by a MUSCL-type TVD scheme and 4th order accurate Runge-Kutta time integration scheme. A series of numerical studies are carried out for the different regimes of the detonation phenomena to investigate the computational requirements for the simulation of the detonation wave cell structure by varying the reaction constants and grid resolutions. The computational results are investigated by comparing the solution of steady ZND structure to draw out the minimum grid resolutions and the size of the computational domain for the capturing cell structures of the different regimes of the detonation phenomena.

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Performance of Variable-Phase Thyristor Motor (변상싸이리스터전동기의 특성)

  • 황영문;이일천;김광태
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.33 no.4
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    • pp.127-133
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    • 1984
  • In this paper the performance of a variable-phase thyristor motor combined with a phase splitter and a single-phase tapped induction motor is investigated. The phase splitter consists of a bridge type thyristor switching circuit. The regulating power flow of the phase splitter is obtained from the switching phase difference of thyristor switching sequences. The proper switching performance improves the torque-speed-characteristics of the motor and its operation efficiency. We simplify the motor system th using the tapped windng reactances of the motor as the complementary element of the thyristor phase splitter. We discussed the practicality of this motor system through the analysis of simulation result and the voltage and the current wave forms obtained froms obtained from the experiment.

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SCHEDULING TECHNIQUE FOR CONTROL STEP (스케듈링 기법 연구)

  • JeongYoungSong;NamWooBack
    • Journal of the Korean Geophysical Society
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    • v.4 no.3
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    • pp.163-173
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    • 2001
  • This paper deals with scheduling problems which are the most important subtask in High-Level Synthesis. Especially, we have concentrated our attentions on the data-path scheduling which can get the structural informaion trom the behavioral algorithm as a first step in synthesis procedure. Suggest Forward scheduling methode is executed the ASAP and ALAP scheduling to use the fifth - order elliptic wave filter of a standard benchmark moedl, and then it is drawing up T.N matrix table by the number resource and control-step, using the table extract of the simple than down-limit value of the control-step for the number of given resource th use this table. All of existing list scheduling techniques determine the priority function first, and then do the operation scheduling, But, the suggested forward scheduling technique does the schedule first, and determines the priority functions if needed in scheduling process.

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A Study on the Optical Properties of the Organic Thin Films by Plasma Polymerization (플라즈마 중합법에 의한 유기 박막의 광학 특성에 관한 연구(I))

  • Choi, C. S.;Jung, U.;Lee, D. C.;Park, G. B.;Park, S. H.;Park, B. K.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1992.05a
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    • pp.26-29
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    • 1992
  • In this study, We made use of interelectrode capacitively coupled type plasma polymerization apparatus in order to make th organic optical thin films. We adopted in Benzen. Styrene, which have optical function in the organic world. It is manufactured polymerization thin films and examined optics properties by it respectively. We have known that the refractive index decreased as discharging power increased. At the middle wave length as 550[nm], the refractive index of Styrene is smaller than one of Benzen. Then, it is known that measured results are valid because the extinction coefficient(K) is about 10$\^$-4/ for variation of refractive index.

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