• Journal of the Optical Society of Korea
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• 제4권2호
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• pp.79-85
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• 2000

The main purpose of this paper is to present the potential of photovoltaic systems using holographic solar concentrators. A hologram used here focuses light, spectrally splits it and diverts unwanted infrared heat away from the solar cell. The output of the hologram appears as a perpendicular thin spectral line and is displaced to solar cells on both sides. To obtain optimum design conditions we used the coupled wave theory and the vector ray tracing method. The measured data showed that the diffraction efficiency was 75 ％ and the spectral bandwidth was 350 nm.

• 한국측량학회지
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• 제15권2호
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• pp.185-193
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• 1997

While close range photogrammetry has been widely applied for static deformation analysis, video cameras have many characteristics that make them the sensors of choice for dynamic analysis of rapidly changing situations. They also have limitations. The aim of this research is to explore the potential of a video system for monitoring dynamic objects. A pilot system consists of two camcorders, VCR, and PC with frame grabber. To estimte the performance of this system for moving objects, a car was imaged covering several phases when starting to drive. The sequential images of a moving car were recorded on VCR. 15 images per second were digitized in an off-line mode by frame grabber. The image coordinates of targets attached to the rear bumper of a car were acquired by IDRISI, and the object coordinates were derived based on DLT. This research suggests that home video cameras, PC, and photogrammetric principles are promising tools for monitoring of the moving objects and vibrations as well as other time dependent situations.

• EDISON SW 활용 경진대회 논문집
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• 제6회(2017년)
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• pp.534-538
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• 2017

There are three types of robots that move on the ground classified as drivetrain. Wheels, tracks and Legs. Wheels and tracks are much easier to construct and control, but they have problems passing through obstacles like people. This paper discusses the design of line tracing using Theo Jansen, one of multi-legged walking mechanism. In order to increase the moving speed, the Jansen mechanism is designed by maximizing the objective variable as GL (Ground Length), GAC (Ground Angle Coefficient). In this project, only three sensors were attached and Arduino was used for optimal control of the motor using the sensor values.

• EDISON SW 활용 경진대회 논문집
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• 제6회(2017년)
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• pp.580-584
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• 2017

본 논문에서는 얀센 메커니즘을 이용한 4족 보행 로봇의 설계와 라인 추적을 통해 목표지점까지 도달할 수 있도록 하는 센싱에 대해 보인다. 가장 핵심이라고 판단되는 구동부의 최적 설계를 위해 m.Sketch를 이용하여 GAC와 GL를 설정하였고, 최적 설계 후 다리 경량화를 통한 로봇 속도 개선 등의 문제는 차후에 다루기로 한다. 본 논문에서 언급되는 모든 구동부는 이론적 계산을 기초로 하여 CATIA 프로그램을 사용하여 제작되었으며, 과학상자를 이용한 여러 번의 구조변경 실험을 통해 최적의 설계를 찾는 것을 목표로 한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 춘계학술대회 논문집
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• pp.185-191
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• 1999

This paper deals with a method to predict the noise level inside metro electric cars running a single-line tunnel at the speed of 80km per hour using ray tracing method, a kind of ray acoustics generally used for a high-frequency and air-born noise analysis. The interior of the car including a under-frame, seats, side doors, end doors, door-pockets, side panels, end panel, a roof panel and so on is modeled. And in order to describe the noise power coming inside, artificial noise sources are designated using sound transmission loss data of each section measured from simple tests and external noise level. The noise level inside the car is calculated and its properties are investigated. The results satisfy the criteria on noise level inside the car.

• 한국정보처리학회논문지
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• 제1권3호
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• pp.409-417
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• 1994

고도행렬로부터 등고선을 추출하는데 있어, 가장 중요한 문제는 하나의 격자에 네개의 통과점이 발생하는 이상 상황(degenerate case)의 해결이다. 본 논문은 이상 상황 검사와 다음점 결정을 동시에 수행하는 방법을 기술한다. 이 방법은 최소 횟수 의 배열 인덱싱을 필요로 한다. 또한 통과점을 모서리점의 높이차에 따라 LOWER/ HIGHER로 표시하고, 이 정보를 이용하여 보다 적은 횟수의 배열 인덱싱을 필요로하는 방법을 제안한다. 그리고 통과점을 표시하고 이들을 추적하기에 적합한 자료구조를 구체적으로 기술한다.

• 한국자동차공학회논문집
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• 제11권5호
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• pp.193-200
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• 2003

A computer simulation program to evaluate the performance of railway systems and train operation plans and the effects of new technologies is provided. The program has the functions of tracing the movements of trains on railway network following the indication of railway signalling system and obeying all kinds of operation rules. An object-oriented technique is applied to model railway system effectively, and it is expected that the program code can be reused easily for other railway simulation programs. Dedicated graphic user interface displaying the simulation outputs by animation during simulation process makes the program convenient to use. Simulation results on the train operations on Kyung-bu line show the proposed program is promising.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1268-1271
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• 2003

In the edge detection of RS image, the useful detail losing and the spurious edge often appear. To solve the problem, we use the dyadic wavelet to detect the edge of surface features by combining the edge detecting with the multi-resolution analyzing of the wavelet transform. Via the dyadic wavelet decomposing, we obtain the RS image of a certain appropriate scale, and figure out the edge data of the plane and the upright directions respectively, then work out the grads vector module of the surface features, at last by tracing them we get the edge data of the object therefore build the RS image which obtains the checked edge. This method can depress the effect of noise and examine exactly the edge data of the object by rule and line. With an experiment of a RS image which obtains an airport, we certificate the feasibility of the application of dyadic wavelet in the object edge detection.

• Design & Manufacturing
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• 제16권2호
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• pp.20-25
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• 2022

In line with the rapid economic growth of many countries, fossil fuel energy sources are also rapidly depleting. Therefore, the price is also rising rapidly, so it is necessary to develop new and renewable energy sources such as hydropower, geothermal power, nuclear power, wind power and solar energy to replace fossil fuel energy in the future. In this study, development of rotating concentrator module system, development of rotating module control control system, development of lamp and charge control controller, configuration and prototype production of rotating concentrating solar LED street light system, efficiency of rotating concentrating solar LED street light, and power production. The research was conducted in the order of evaluation of comprehensive performance tests such as consumption and consumption. As a result, the developed high-efficiency rotation-concentrating hybrid solar LED street light module system has a 50% higher light-gathering efficiency than existing products by tracing sunlight by self-developing a rotation-collecting module on existing solar LED street lamps according to the characteristics of Korea's topography. and the power generation was improved by more than 40%.

• 한국정보과학회논문지:데이타베이스
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• 제36권3호
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• pp.198-214
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• 2009

RFID 태그의 시공간 이력정보는 리더에 의해 수집된 선분인 태그간격으로 모델링될 수 있으며, 태그 식별자(TID), 위치 식별자(LID), 시간(TIME)을 축으로 하는 3차원 도메인에서 색인될 수 있다. 도메인 공간에서 태그간격의 분포는 태그 위치추적 질의의 성능을 결정짓는 주요 요소이며 이는 각 도메인 좌표의 정렬에 따라 달라진다. 특히, 시간에 따라 변경되는 태그의 위치 이력을 검색하는 태그 위치추적 질의는 위치정보를 제공하는 LID가 도메인에서 정렬되는 순서에 따라 성능이 달라진다. 따라서, 색인에 저장된 태그간격의 검색 성능 향상을 위해서는 최적의 LID 순서를 결정하는 것이 필요하다. 이를 위하여 이 논문에서는 LID 간의 새로운 순서화 기준으로써 적용하기 위한 LID 근접성을 정의하고, 질의 시 함께 접근되는 태그간격을 색인에서 근접 저장하기 위한 LID 근접성 함수를 제안한다. 또한, 이를 기반으로 이미 부여된 LID의 재순서 기법을 제안한다. 성능 평가 결과 이 논문에서 제안한 LID 재순서 기법을 색인에 적용했을 때 기존의 LID 부여방식보다 월등한 질의 성능 향상을 보여주고 있다.