• 한국측량학회:학술대회논문집
• /
• 한국측량학회 2007년도 춘계학술발표회 논문집
• /
• pp.451-454
• /
• 2007

There is an inseparable relation between human race and engineering work. As world developed into highly industrialized society, a diversity of large structures is being built up correspondently to limited topographical circumstance. Though large structures are national establishments which provide us with convenience of life, there are some disastrous possibilities which were never predicted such as ground subsidence and degradation. It is very difficult to analyze the volume of total metamorphosis with the relative displacement measurement system which is now used and it is impossible to know whether there is structural metamorphosis within a permissible range of design or not. In this research with an object of 13-year-old earthen dam, through generating point-cloud which has 3D spatial coordinates(x, y, z) of this dam by means of 3D Laser Scanning, we can get real configuration data of slanting surface of this dam with this method of getting a number of 3D spatial coordinates(x, y, z). It gives 3D spatial model to us and we can get various information of this dam such as the distance of slanting surface of dam, dimensions and cubic volume. It can be made full use of as important source material of reinforcement and maintenance works to detect previously the bulging of the dam through this research.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1992년도 추계학술대회 논문집
• /
• pp.266-270
• /
• 1992

In this study an active vision system using a laser range finder is proposed for the navigation of a mobile robot in unknown environment. The laser range finder consists of a slitted laser beam generator, a scanning mechanism, CCD camera, and a signal processing unit. A laser beam from laser source is slitted by a set of cylindrical lenses and the slitted laser beam is emitted up and down and rotates around the robot by the scanning mechanism. The image of laser beam reflected on the surface of an object is engraved on the CCD array. A high speed image processing algorithm is proposed for the real-time navigation of the mobile robot. Through experiments it is proved that the accurate and real-time recognition of environment is able to be realized using the proposed laser range finder.

• 한국ITS학회 논문지
• /
• 제11권4호
• /
• pp.95-103
• /
• 2012

본 논문에서는 송전선로 중장비 접촉사고 방지를 위한 감시 시스템을 구현하였다. 시스템의 설계는 레이저 스캔기술을 적용하여 설계하였다. 설계한 시스템의 세부적 기능을 분석하였다. 감시 시스템을 구현하여 감시파라미터인 검출율과 오류율을 측정하였으며 기존 감시시스템과 비교하였다. 측정결과 기존대비 검출율은 95.8%에서 100%로 향상되었고, 오류율은 2.1%에서 0%로 개선된 결과를 보였다. 연구한 시스템은 접촉사고에 가능성이 있는 위해 개소의 중장비를 감지하고 현장작업자와 관리자에게 정보를 제공하여 사고를 예방해 주는 시스템이므로 송전선로 접촉사고 방지를 위한 감시시스템에 유용하다.

• 대한소아치과학회지
• /
• 제33권1호
• /
• pp.1-12
• /
• 2006

최근 새로 개발된 DIFOTI(Digital Imaging Fiber-Optic Transillumination) 시스템의 초기 법랑질 우식증 진단 능력을 평가하고 임상 적용의 가능성을 타진해 보고자 본 연구를 시행하였다. 임상 연구는 유치 탈락 시기에 근접한 학령기 아동 23명을 대상으로 DIFOTI 이미지 촬영을 시행하고 자연 탈락된 유치 20개를 수거하여 CLSM 촬영 결과를 바탕으로 민감도(sensitivity)와 특이도(specificity)를 산출하였으며 실험실 연구에서는 수거된 40개의 유치를 대상으로 Carbopol 인공 우식 용액으로 1, 2, 4 그리고 8일간 탈회시킨 후 각각 방사선 사진, DIFOTI 이미지 그리고 CLSM와 비교 분석하여 다음과 같은 결론을 얻었다. 1. 구내에서 촬영한 DIFOTI 이미지의 민감도는 0.61이었고, 특이도는 0.63이었다. 2. 실험실에서 인공 탈회시킨 유치의 협설면 초기 우식증에 대한 DIFOTI 이미지의 민감도는 0.71였고, 특이도는 0.75였다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
• /
• pp.145-148
• /
• 1986

To perform the marking on metal with high speed and non-contact using the laser beam of high energy, laser marking system is designed and fabricated applying the galvanometer scanner capable of high speed-precise beam positioning controlled by microprocessor. Laser is a Q-switched Nd:YAG producing multi-mode, wavelength, 1060nm. Optical system is composed of beam expander, scanning mirror and flat field lens. Consequently, the laser marking is satisfactorily achieved regardless of kinds of metal.

• 한국측량학회지
• /
• 제27권3호
• /
• pp.347-356
• /
• 2009

최근 산업계를 비롯한 다양한 분야에서 대상물에 대한 3차원 측정과 형상화에 대한 요구가 급증함에 따라 측정 및 3차원 모델링을 위한 3차원 레이저스캐닝 시스템의 활용이 급증하고 있다. 그러나 3차원 레이저 스캐닝 시스템의 역할 및 활용의 증가하고 있는데 반해 스캔에 의해 획득되는 결과에는 다양한 원인에 의한 오차가 포함됨으로 인하여 고정밀 측정이 요구되는 분야에서 활용에 부분적인 제약으로 작용하고 있다. 이에 본 연구에서는 레이저측정방식을 채용하고 있는 3차원 레이저스캐닝 시스템을 이용하여 오차발생의 가장 큰 요인으로 조사되고 있는 측정대상을 표면물질의 반사율에 따른 오차발생특성과 발생비율을 분석함으로써 3차원 스캔자료의 정확도 향상을 꾀하고자 하였다. 연구결과, 측정대상물의 표면물질에 따라 반사량이 다르게 나타남을 확인할 수 있었으며, 표면반사율과 레이저파의 반사량 사이에 비례관계가 성립되는 특성을 확인할 수 있었다.

• 한국정밀공학회지
• /
• 제23권4호
• /
• pp.183-190
• /
• 2006

Digital 3D Real Object Duplication System (RODS) consists of 3D Scanner and Solid Freeform Fabrication System (SFFS). It is a device to make three-dimensional objects directly from the drawing or the scanning data. In this research, we developed an office type SFFS based on Three Dimensional Printing Process and an industrial SFFS using Dual Laser. An office type SFFS applied sliding mode control with sliding perturbation observer (SMCSPO) algorithm for control of this system. And we measured process variables about droplet diameter measurement and powder bed formation etc. through experiments. In case of industrial type SFFS, in order to develop more elaborate and speedy system for large objects than existing SLS process, this study applies a new Selective Dual-Laser Sintering (SDLS) process and 3-axis Dynamic Focusing Scanner for scanning large area instead of the existing f lens. In this process, the temperature has a great influence on sintering of the polymer. Also the laser parameters are considered like that laser beam power, scan speed, and scan spacing. Now, this study is in progress to evaluate the effect of experimental parameters on the sintering process.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.107.5-107
• /
• 2001

In this report, as the active position measurement system, a new method for two-dimensional position measurement system using a concept of semi-open type signal field has proposed. The feature of this system is realizing a position measurement only by scanning the encoded laser beams from scanning points to a measurement field, and observed it. First, both system configuration and encoding method are considered concretely, and M-sequence signal is selected for encoding. Next system design is performed to realize the theoretical measurement accuracy, and applied to a position measurement experiments. Experimental results show that measurement precision is larger than theoretical values. Furthermore, method for improving the measurement ...

• Current Optics and Photonics
• /
• 제2권6호
• /
• pp.595-605
• /
• 2018

The two-photon process of microscopy provides good spatial resolution and optical sectioning ability when observing quasi-static endogenous fluorescent tissue within an in vivo animal model skin. In order to extend the use of such systems, we developed a two-photon laser scanning microscopy system capable of also capturing $512{\times}512$ pixel images at 90 frames per second. This was made possible by incorporating a 72 facet polygon mirror which was mounted on a 55 kRPM motor to enhance the fast-scan axis speed in the horizontal direction. Using the enhanced temporal resolution of our high-speed two-photon laser scanning microscope, we show that rapid processes, such as fluorescently labeled erythrocytes moving in mouse blood flow at up to 1.2 mm/s, can be achieved.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2006년도 춘계학술대회 논문집
• /
• pp.193-194
• /
• 2006

A solid freeform fabrication (SFF) system using selective laser sintering (SLS) is currently recognized as a leading process and SLS extends the applications to machinery and automobiles due to the variousmaterials employed. In order to develop a more elaborate and rapid system for fabricating large objects compared to existing SLS, this study employs a new selective dual-laser sintering (SDLS) process. Also, this paper will address development of an SFF system which employs the dual laser system and the unique scanning device. Experiments were performed to evaluate the effect of a scanning path and fabrication parameters on sintering process and to fabricate the various 3D objects using polymer powder.