• 제목/요약/키워드: Mixed mode design

검색결과 122건 처리시간 0.027초

소형 MR감쇠기의 성능 실험에 기초한 준능동 제어 시스템 (Semi-Active Control System Based on the Experimental Results of the Performance of a Small Scale MR Damper)

  • 민경원
    • 한국전산구조공학회논문집
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    • 제19권3호
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    • pp.233-238
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    • 2006
  • 이 논문에서는 소형 다층 구조물의 진동제어에 적용하기 위한 복합모드의 자기유변유체(MR) 감쇠기를 개발하였다. 우선, 도식적으로 전단, 유동, 복합모드 MR감쇠기의 형태를 설계조건과 함께 표현하였고, 각각의 모드에 대하여 자기장에 따른 감쇠력을 예측하기 위한 해석모델을 유도하였다. 다음으로 적당한 크기의 복합모드 MR감쇠기를 제작하고 자기장에 따른 감쇠특성을 시간영역에서 평가하였다. 마지막으로 지진하중을 받는 소형구조물에 제작된 MR감쇠기가 준능동 제어기로 제어하였을 때의 성능을 수치적으로 평가하였다.

Reflective Twist Nematic Liquid Crystal Display For High Reflectance.

  • Son, Ock-Soo;Park, Young-Il;Beak, Do-Hyoen;Son, Gon;Suh, Dong-Hea
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.292-294
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    • 2008
  • We have developed new reflective LCD for Mixed twist nematic LC mode with high quality image. We have found out an optimal twist angle of LC and optical film's axis by simulation. Also we measured electro-optic characteristics for new design panel. As a result, high reflectance and wide viewing angle characteristics were achieved.

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Structure Optimization of ESD Diodes for Input Protection of CMOS RF ICs

  • Choi, Jin-Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제17권3호
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    • pp.401-410
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    • 2017
  • In this work, we show that the excessive lattice heating problem due to parasitic pnp transistor action in the diode electrostatic discharge (ESD) protection device in the diode input protection circuit, which is favorably used in CMOS RF ICs, can be solved by adopting a symmetrical cathode structure. To explain how the recipe works, we construct an equivalent circuit for input human-body model (HBM) test environment of a CMOS chip equipped with the diode protection circuit, and execute mixed-mode transient simulations utilizing a 2-dimensional device simulator. We attempt an in-depth comparison study by varying device structures to suggest valuable design guidelines in designing the protection diodes connected to the $V_{DD}$ and $V_{SS}$ buses. Even though this work is based on mixed-mode simulations utilizing device and circuit simulators, the analysis given in this work clearly explain the mechanism involved, which cannot be done by measurements.

Investigating risk of overheating for school buildings under extreme hot weather conditions

  • Lykartsis, Athanasios;B-Jahromi, Ali;Mylona, Anastasia
    • Advances in Energy Research
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    • 제5권4호
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    • pp.277-287
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    • 2017
  • This study examines the risk of overheating of a school building, under extreme hot weather conditions, in 14 locations in the United Kingdom using the overheating criteria defined in Building Bulletin 101 (BB101). The building was modelled as naturally ventilated, mechanically ventilated and in mixed mode and was simulated both for the current and the projected weather conditions of the 2050s. Under the current weather conditions, results of the simulations show that when naturally ventilated, the school building fulfils the BB101 criteria only in the areas of Edinburgh and Glasgow. In the simulations of the building as mechanically ventilated and in mixed mode, mechanical cooling was provided in order for the building to comply with the overheating criteria. A comparison of the required cooling loads between the two scenarios shows that application of mixed mode ventilation results in less cooling loads.

혼합모드 피로문제에서의 최소 변형에너지 밀도기준의 적용 (An Application of Minimum Strain Energy Density Criterion in Mixed Mode Fatigue Problem)

  • 심규석;구재민
    • 한국안전학회지
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    • 제17권2호
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    • pp.1-7
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    • 2002
  • In this paper, the maximum minimum strain energy density criterion was applied to the mixed mode fatigue test of A5052 H34 alloy. In this study result we can have seen that the authors stress intensity factor for the finite width specimen and method of determining testing load, based on the plastic zone size and the limited maximum stress intensity factor by ASTM STANDARD E-647-95, is useful.

FPGA 구현을 통한 자이로의 혼합모드 연구 (A Study on the Mixed Mode of Gyros by FPGA Implementation)

  • 노영환;방효충
    • 제어로봇시스템학회논문지
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    • 제8권1호
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    • pp.54-59
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    • 2002
  • In the three-axis control of satellites by using on-board actuators, gyros are usually used to measure the attitude angles and angular rates. The gyros are operated by electronic parts and mechanical actuators. The digital components of the electronic parts consist of largely FPGA (Field Programmable Gate Array) as one of the methods for VLSI(Very Large Scale Integrated) circuit design, while the mechanical parts provide output signal directly by mechanical actuation of a spinning rotor. In this research, a mixed mode of gyro is implemented in FGA. In addition to the hardware implementation, the simulation study was conducted by using the SABER for the mixed mode simulator. Results for the practical implementation of the satellite ACS (Attitude Control System) interfaced with the data processing are also presented to validate the FPGA implementation.

복합모드형 ER엔진마운트의 성능평가 (I);엔진마운트의 제작 및 시험 (Performance Evaluation of a Mixed-Mode Type ER Engine Mount (I);Manufacturing and Test of Engine Mount)

  • 최영태;최승복
    • 대한기계학회논문집A
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    • 제24권2호
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    • pp.370-377
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    • 2000
  • This paper presents a mixed-mode type ER(electro-rheological) engine mount, and its vibration control performance for a passenger vehicle is presented. The field-dependent yield stress of a transfo rmer oil-based ER fluid is empirically distilled in both shear and flow modes. This is then incorporated with the governing equation of motion of the proposed mixed-mode(shear mode plus flow mode) type engine mount. The damping force is analyzed with respect to the intensity of the electric field and design parameters such as electrode gap. Subsequently, the ER engine mount which is equivalent to the conventional hydraulic engine mount in terms of the damping level is designed and manufactured. Both computer simulation and experimental test are undertaken in order to evaluate vibration isolation performance. In addition, this performance is compared with that of the conventional hydraulic engine mount.

환자움직임 감지를 위한 효율적인 하드웨어 및 소프트웨어 혼성 모드 영상처리시스템설계에 관한 연구 (A study on the design of an efficient hardware and software mixed-mode image processing system for detecting patient movement)

  • 정승민;정의성;김명환
    • 인터넷정보학회논문지
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    • 제25권1호
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    • pp.29-37
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    • 2024
  • 본 논문에서는 환자와 같은 특정 객체의 움직임을 감지하고 추적하기 위한 효율적인 영상처리 시스템을 제안한다. 이진화된 차 영상에서 객체의 윤곽선추출을 위하여 기존 알고리즘대비 대비 정밀한 감지가 가능하고 혼성모드설계에 용이한 세선화 알고리즘을 적용하여 영역을 추출한다. 연산량이 많은 이진화와 세선화 단계를 RTL(Register Transfer Level) 기반으로 설계하여 논리회로 합성을 거쳐 최적화된 하드웨어 블록으로 대체된다. 설계된 이진화 및 세선화 블록은 표준 180n CMOS 라이브러리를 이용하여 논리회로로 합성한 후 시뮬레이션을 통하여 동작을 검증하였다. 소프트웨어기반의 성능비교를 위해 32bit FPGA 임베디드시스템 환경에서 640 × 360 해상도의 샘플 영상을 적용하여 이진 및 세선화 연산에 대한 성능분석도 실시하였다. 검증결과 혼성모드 설계가 이전의 소프트웨어로만 이루어지는 처리속도에서 이진 및 세선화 단계에서 93.8% 향상될 수 있음을 확인하였다. 제안된 객체인식을 위한 혼성모드 시스템은 인공지능 네트워크가 적용되지 않는 엣지 컴퓨팅 환경에서도 환자의 움직임을 효율적으로 감시할 수 있을 것으로 기대된다.

혼합모드 균열의 응력확대계수 해석과 정도 개선에 대한 고찰 (Determination of S.I.F. for Mixed Mode Crack and Development of Accuracy)

  • 배원호
    • 한국산업융합학회 논문집
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    • 제7권4호
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    • pp.355-361
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    • 2004
  • The finite element method were used to determine the stress intensity factor of cracked plate. The stress method, displacement method and J Integral are most popular finte element method. ANSYS proposed another a kind of displacement method. In this paper, it was examined that the accuracy and utility of the ANSYS method could believable to determine the stress intensity factors of centered inclined crack. Generally, inclined crack has two portion of stress intensity factors, tensile mode F1 and shear mode F2. For the purpose of increasing the accuracy of stress intensity factors, examined the effect of the numbers of nodes and elements, crack tip element size and number of partition of the crack tip vicinity. It was found that the method proposed by ANSYS is useful and has high accuracy. Accuracy of calculated stress intensity factors was increased by increase of the number of nodes and elements, and at the small size of crack tip elements can get more highly accuracy.

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