• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2004년도 춘계 학술대회논문집
• /
• pp.27-34
• /
• 2004

In the Smart UAV Development Program, one of the 21c Frontier R&D Program, the tiltrotor has been studied as the concept of vehicle. The tiltrortor aircraft take-off and land in rotary wing mode like conventional helicopter, and cruise in fixed wing mode like conventional propeller airplane. For the conversion of the flight mode from helicopter to airplane, the nacelle located at wing tip has to be tilted from about 90 degrees of helicopter mode to about 0 degree of airplane mode. In this study, the aerodynamic characteristics of the wing with tilted nacelle is investigated using computation fluid dynamics technique. In order to feature out aerodynamic interferences between wing and nacelle, the flow calculations are conducted for the wing and the nacelle separately and for the combined geometry of wing and nacelle, respectively. Through this computations, not only the aerodynamic data-base for the wing-nacelle is constructed but also its contribution to the configuration design of the wing-nacelle is anticipated.

• Journal of Electrical Engineering and Technology
• /
• 제2권4호
• /
• pp.537-542
• /
• 2007

This paper proposes a 2-step Kalman filter model for land vehicle navigation using civilian-band GPS measurements. The velocity bias caused by the Earth#s rotation would be removed completely when applying this model. Because the linearization of velocity equations in this model is not necessary, the error is significantly reduced. The experiment reveals that estimated position error with stationary data is about 5m during a 15-20 minute interval. The other benefit of this model is that it can be feasibly applied as a GPS receiver module thanks to the small sizes of the necessary manipulating matrices.

• 대한의용생체공학회:의공학회지
• /
• 제15권1호
• /
• pp.27-34
• /
• 1994

In this paper. a way to analysis a corridor scene for a vehicle's automatic locomotion is presented In general, it's necessary for a vision system of vehicles to identify its positions in given environments. The suggested algorithm is to decide base lines of a corridor image using the vanishing point finding. Feature points are extracted on the base line using a base line extraction tree. This algorithm is suitable for a motorized wheelchair's self locomotion in a building.

• Structural Engineering and Mechanics
• /
• 제18권5호
• /
• pp.609-626
• /
• 2004

The Land Transport Authority of Singapore has a continuing program of highway bridge upgrading, to refurbish and strengthen bridges to allow for increasing vehicle traffic and increasing axle loads. One subject of this program has been a short span bridge taking a busy highway across a coastal inlet near a major port facility. Experiment-based structural assessments of the bridge were conducted before and after upgrading works including strengthening. Each assessment exercise comprised two separate components; a strain and acceleration monitoring exercise lasting approximately one month, and a full-scale dynamic test carried out in a single day. This paper reports the application of extreme value statistics to estimate bridge live loads using strain measurements.

• Elastomers and Composites
• /
• 제53권1호
• /
• pp.13-18
• /
• 2018

A face seal comprising a metal ring and acrylonitrile butadiene rubber (NBR) was installed in the driving part and suspension unit. The seal serves as a bearing and simultaneously prevents entry of foreign matter from external environment as well as internal oil leakage. Subsequently, the rubber-rod ring generates axial pressure owing to rubber elasticity (hardness), performs static sealing function between housing details and outer diameter of seal, and transmits rotational torque to the rotating support ring. In order to improve the durability of NBR, which performs the above tasks, and to effectively use it in tracked-vehicle applications at extreme temperatures, this study reports a mixing design approach to enhance cold and oil resistances of NBR.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (2)
• /
• pp.497-499
• /
• 1998

비젼 시스템을 바탕으로 한 무인 주행 시스템은 카메라로부터 입력된 영사에서 도로와 비 도로를 적절히 인식하여 그것을 바탕으로 주행을 위한 여러 장치들을 제어하는 시스템이라 할 수 있다. 한편 이와 같이 영상의 인식 결과가 핸들 제어나 속도 제어의 성능을 결정할 때 무엇보다 도로의 환경 변화에 강건한 비젼 시스템의 구현이 요구된다. 본 논문에서는 비젼 시스템과 핸들 제어 시스템 두 부분을 구현하였는데, 비젼 시스템에서는 입력 영상에 대해 학습이 가능한 Multilayer Perceptron(MLP)을 이용하여 도로와 비 도로를 적절한 신뢰도로 나눈 후 피라미드 알고리즘을 거쳐 최종 도로 영역을 추출해 낸다. 핸들 제어를 위해 도로 영역의 외곽선을 모델링한 후 차량의 주행 방향 벡터를 구한다. 그 값이 핸들 제어 시스템에서의 MLP의 입력이 되어 차량의 핸들 각도를 결정하게 된다. 끝으로 옥외 차량 시뮬레이션을 통하여 본 논문에서 제안된 알고리즘의 유용성을 확인한다.

• 대한안전경영과학회지
• /
• 제17권4호
• /
• pp.153-160
• /
• 2015

Recent News patrons of incidents can be called sinkhole that occurred one after another (Sink Hole). Due to this anytime, anywhere I do not know how the land is turned off worry and anxiety is the reason why you can never be dismissed as exaggerated. As we have seen today through the video, the vehicle was traveling on a road or pedestrian who was walking down the street they look out of the basement of a sudden they still come to mind vividly. Here, examples and corresponding measures to prevent the sinkhole off the ground, including the causes and impact on society because of this that occurred, and policy measures and abroad are evaluated with respect to what it is.

• 한국군사과학기술학회지
• /
• 제19권5호
• /
• pp.567-573
• /
• 2016

GMAW and GTAW processes have been used for welding of equipment mounting pads during decades. For improving the mobility and survivability of KWV(Korean Wheeled Vehicle), various types of equipment are required and numbers of pads for welding were increased. In this research, for improving productivity of mounting pads welding process, new technology of stud welding was studied. In this study, mechanical properties of stud weldment were investigated to compare with those of GMAW weldment. Also, research of stud weldment durability was carried out and proved its fatigue strength under the condition of KWV's 32,000 km load profile.

• 한국방송∙미디어공학회:학술대회논문집
• /
• 한국방송공학회 2015년도 추계학술대회
• /
• pp.165-168
• /
• 2015

최근 디지털 콘텐츠 및 멀티미디어는 거의 모든 IT 산업에서 중요한 역할을 하고 있으며, 이중에서도 비디오 콘텐츠는 그 동안의 검색, 유통, 관리 등의 수동적인 범위를 넘어 실세계와의 실시간 상호작용을 통한 능동적이며 혁신적인 역할을 수행하고 있다. 실시간 비디오 검색 기술은, 다양한 분야에서 활용이 가능한데, 대표적인 서비스 분야는 ALV(Autonomous Land Vehicle : 무인자동차), SNS 서비스, 오락/스포츠/광고 서비스, 모바일 쇼핑, AR, Surveillance 분야 등 매우 다양하다. 본 논문에서는, 실시간 비디오 검색 기술의 개요와 적용분야 및 사례를 설명하고 실시간 비디오 검색기술을 객관적으로 평가할 수 있는 방법, 절차에 대한 인증서에 대한 규격을 제정하여, 사용자가 표준화된 실시간 비디오 검색 기술의 인증서의 내용을 토대로 자신의 목적에 따라 기술을 선택하여 사용할 수 있도록 하였다.

• 한국복합재료학회:학술대회논문집
• /
• 한국복합재료학회 2000년도 추계학술발표대회 논문집
• /
• pp.187-190
• /
• 2000

Cyclocopter is air vehicle to vertically take-off and land like a helicopter. This is an efficient and quiet means of being able to direct thrust compared to a helicopter. The rotor consists of several blades rotating about a horizontal axis perpendicular to the direction of normal flight. The direction of blade span is parallel to rotating axis and both end roots are connected to the hub to resist centrifugal force and to transmit the power. The pitch of the individual blades to the tangent of the circle of the blade's path is varied cyclically to gain thrust. In the paper, the design and manufactures of cyclocopter rotor blades are presented. Stress at the roots of cyclocopter blades is great due to centrifugal and aerodynamic forces and aeroelastic instabilities appear. The blades consist of main spar, front spar, polyurethan foam, weight, and skin and spars and skin are made of glass/epoxy composite.