• 제목/요약/키워드: Change of direction

검색결과 3,222건 처리시간 0.037초

움직임 방향 치우침 특성을 이용한 십자형 다이아몬드 탐색 (Cross Diamond Search Using Motion Direction Biased Characteristics)

  • 류권열
    • 한국정보통신학회논문지
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    • 제13권8호
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    • pp.1527-1533
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    • 2009
  • 본 논문에서는 MVP 분포의 움직임 방향 치우침 특성을 이용한 방향성 탐색 패턴을 디자인하고, 탐색점의 이동 방향에 따라 탐색 패턴을 적응적으로 변화시키는 방향 적응적 십자형 다이아몬드 탐색 방법을 제안 한다. 제안한 방법은 이웃 매크로 블록으로부터 모션 벡터를 예측하고, 예측한 모션 벡터를 이용하여 초기 움직임 방향을 설정 한다. 탐색 과정에서 BMP의 이동 방향에 따라 제안한 탐색 패턴을 적응적으로 변화시킴으로써 탐색 효율을 향상시킨다. 실험 결과, 제안한 방법 은 움직임 추정에 소요되는 계산량을 기존의 십자형 다이아몬드 탐색에 비해 $0.43%{\sim}1.76%$ 감소시킴으로써 고속 움직임 추정이 가능함을 알 수 있었다.

원형평판의 지지조건을 구성하는 양 끝단의 면적변화에 따른 강성도 해석 (The Stiffness Analysis of Circular Plate Regarding the Area Change of Both Ends Constructing Supporting Conditions)

  • 한근조;안찬우;김태형;안성찬;심재준;한동섭
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.908-911
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    • 2002
  • This paper investigates the characteristics of deflection for circular plate that has same supporting condition along the width direction of plate according to the area change of supporting end. For two boundary conditions such as simple supporting and clamping on both ends, this study derives maximum deflection formula of circular plate using differential equation of elastic curve, assuming that a circular plate is a beam with different widths along the longitudinal direction. The deflection formula of circular plate is verified by carrying out finite element analysis with regard to the ratio of length of supporting part to radius of circular plate.

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건타입 버너의 토출공기에 대한 선회기의 스월 수 영향 (Effect of the Swirl Number of Spinner on the Exhaust Air of the Gun Type Burner)

  • 고동국;윤석주
    • 한국분무공학회지
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    • 제20권2호
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    • pp.70-75
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    • 2015
  • Swirl flow in the gun type burner has an impact on the stabilization of the flame, improvement of the combustion efficiency. The swirl flow is created by the spinner which is inside the airtube that guide the combustion air. Gun type burner has generally the inner devices composed electronic spark plug, injection nozzle, combustion device adaptor, and spinner. These inner components change the air flow behavior passing through airtube. So, this study conducted the measurement using by hot-wire anemometer and analyzed effect of the swirl number of spinner on the exhaust air of gun type burner. Turbulence characteristics come up in this study was mean velocity, turbulence intensity, kinetic energy, shear stress and flattness factor of the air flow with the change of the distance of axial direction and tangential direction from the exit of the airtube.

개별 블레이드 피치 제어 방식을 이용한 수직축 풍력발전기의 성능 해석 및 시스템 구현 (Aerodynamic Analysis and System Implementation of Vertical Axis Wind Turbine using Individual Blade Pitch Control Method)

  • 정인오;이윤한;황인성;김승조
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.3347-3352
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    • 2007
  • This paper describes a research for the performance improvement of the straight-bladed vertical axis wind turbine. To improve the performance of VAWT, the individual blade pitch control method is adopted. For the wind turbine, CFD analysis is carried out by changing blade pitch angle according to the change of wind speed and wind direction. By this method, capacity and power efficiency of VAWT are obtained according to the wind speed and rotating of rotor, and could predict the overall performance of VAWT. It was manufactured to verify performance of the experimental system that consists of rotor including four blades and base. Furthermore, torque sensor and power generator were installed. Also, active controller which can change the pitch angle of the individual blade according to the wind speed and direction was used.

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수학사 연구 방향의 두 갈래와 '기하학적 대수학' (Two fundamental direction over historical research of mathematics and geometrical algebra)

  • 한경혜
    • 한국수학사학회지
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    • 제20권2호
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    • pp.33-46
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    • 2007
  • 본고에서는 1970년대 이후로 전개된 수학사 연구의 기본 방향의 변화를 다룬다. 그 가운데서도 유클리드 <원론> II권의 내용인 이른바 '기하학적 대수학'에 대한 해석을 둘러싸고 벌어진 일련의 논쟁이 어떻게 전개되었는지를 소개하고, 그 논쟁이 수학사 연구의 방향 전환과 어떤 관련성을 띠는지를 밝히도록 한다.

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경사가 있는 지형의 거칠기 아층에서 풍향시어와 운동량 플럭스의 특성 (Characteristics of Wind Direction Shear and Momentum Fluxes within Roughness Sublayer over Sloping Terrain)

  • 이영희
    • 대기
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    • 제25권4호
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    • pp.591-600
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    • 2015
  • We have analyzed wind and eddy covariance data collected within roughness sublayer over sloping terrain. The study site is located on non-flat terrain with slopes in both south-north and east-west directions. The surface elevation change is smaller than the height of roughness element such as building and tree. This study examines the directional wind shear for data collected at three levels in the lowest 10 m in the roughness sublayer. The wind direction shear is caused by drag of roughness element and terrain-induced motions at this site. Small directional shear occurs when wind speed at 10 m is strong and wind direction at 10 m is southerly which is the same direction as upslope flow near surface at this site during daytime. Correlation between vertical shear of lateral momentum and lateral momentum flux is smaller over steeply sloped surface compared to mildly sloped surface and lateral momentum flux is not down-gradient over steeply sloped surface. Quadrant analysis shows that the relative contribution of four quadrants to momentum flux depends on both surface slope and wind direction shear.

저전력 및 설비간략화를 위한 선로전환기용 융설장치 설계 (Design of Improved Switch Point Heating System for Low Power and Simplified Equipment)

  • 장동완;전태현
    • 조명전기설비학회논문지
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    • 제27권1호
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    • pp.61-67
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    • 2013
  • The turnout point system is installed to separate the main rail track from other tracks in rail load stations. It is also important to set up the switch point system to change the direction of the turnout point, to lead and change the direction of tracks. The switch point system can be negatively affected by heavy snow during winter seasons which can cause critical safety problems. Furthermore, the maintenance and repair of the conventional system is prohibitively expensive due to its complexity and high probability of failure. In this paper, an efficient switch point system is proposed which simplifies the equipment structure and lowers the cost for maintenance and repair, while improving safety and performance of the rail road system.

견의 탄닌처리에 관한 연구(II) - 매염제의 영향을 중심으로 - (A Study on Tannin Treatment of silk fabrics(II) - The effect of mordants -)

  • 설정화;최석철
    • 한국염색가공학회지
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    • 제6권2호
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    • pp.1-9
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    • 1994
  • In order to study the effect of mordanting on silk fabrics treated with tannin, those fabrics were treated with Al, Cu, Cr, Fe, Sn by pre and post mordanting. It was studied about color change, weighting effect, dgree of photodegradation by pre and post mordanting. The results are as fallows ; 1. On the addition of mordants into mimosa and tannic acid solution, &{\lambda}_{max}& of the former was slightly blue-shifted, on the other hand, &{\lambda}_{max}& of the latter was obviously Red-shifted. 2. In case of Cu, Cr, Pre mordanting, weighting effect were appeared. Weighting effect of silk fabrics treated with Tannic acid increased higher than mimosa by mordanting. 3. In color change, Silk fabrics treated with Mimosa and Tannic acid generally changed to red direction and fabrics treated with tannic acid changed to yellow direction by pre and post mordanting. 4. In the photodegradation, the degree of photodegradation on mordanted fabrics increased. Its degree was slack in Cu, Cr, Post mordanting. On the other hand, Al, Fe, Sn were greate. Silk fabrics treated with Mimosa and Tannic acid got inhibiting effect on photodegradation.

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New Dynamic Fiber Orientation Sensor Based on Dielectric Anisotropy Measurement Technology

  • Sawamoto, Hidetada;Nagata, Shinichi
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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    • pp.161-166
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    • 2006
  • A new fiber orientation sensor has been developed and tested on an actual paper machine to demonstrate its capability to function as a real-time monitoring system. First, we demonstrate the ability of the sensor system to detect the change in the fiber orientation angle while the sensor head, and not the paper, was intentionally rotated from $-90^{\circ}\;to\;+70^{\circ}$ with respect to the paper-traveling direction. Next, we demonstrate that this system can successfully detect the change in the magnitude and angle of fiber orientation in running paper when the direction of material flow on the wire was changed on the paper machine. The angle and magnitude of fiber orientation were independently confirmed by SST and MOA measurements. Furthermore, we found that the system was capable of measuring the basis weight and the moisture content of running paper while detecting the angle and magnitude of fiber orientation.

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퍼지제어에 의한 전동 휠 체어의 경로속도 보정에 관한 연구 (A Study on Phase Velocity Correction of Motorized Wheelchair Based on Fuzzy Control)

  • 이창훈;이동훈;양세준;홍승홍
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1992년도 추계학술대회
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    • pp.71-76
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    • 1992
  • In this study, Fuzzy control algorithm to generate a change of rocomotion cordition according to an outer environment is introduced on a motorized wheelchair control. An optimal control rules for conquesting the less of safety and system inefficiency in the past are given to this motorized wheelchair. And dynamic analysis is also adopted to it. Using those rules, a proportional control was possible when the vehicle changed its moving direction. The proposed method which considers the relationship between a moving velocity and the command from the joystick shows better performance in the change of moving direction.

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