• Title/Summary/Keyword: real-time shape measurement

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Model-Based Moving Object Tracking Algorithm (모델 기반 이동 물체 추적 알고리즘)

  • Kim, Tae-Sik;Kim, Yoon-Ho;Lee, Myong-Kil;Chun, Quan;Lee, Ju-Shin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2000.05a
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    • pp.356-359
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    • 2000
  • In this paper, we propose a model based moving object tracking algorithm in dynamic scene. To adapt the shape change of the moving object, the Hausdorff distance is applied as the measurement of similarity between model and image. To reduce the processing time, 2-D logarithmic search method is applied for locate the position of moving object. Experiments on a running motorcycle, the result showed that the mean square error of real position and tracking result is 1.845 and consequently, matching process is relatively simple and reduced.

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Real-time Gap Control for Micro-EDM: Application in a Microfactory

  • Jung, Jae-Won;Ko, Seok-Hoon;Jeong, Young-Hun;Min, Byung-Kwon;Lee, Sang-Jo
    • International Journal of Precision Engineering and Manufacturing
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    • v.9 no.1
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    • pp.3-6
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    • 2008
  • Electrical discharge machining (EDM) is one of the most widespread nonconventional machining processes. Recently, a low-power micro-EDM process was introduced using a cylindrical electrode. Since its development, micro-EDM has been applied effectively to micromachining, and because the device setup for this process is simple, it is suitable for a microfactory that minimizes machines to fabricate small products economically in one system. In the EDM process, however, the electrode is also removed along with the workpiece. Therefore, the electrode shape and length vary as machining progresses. In this paper, a control method using a high speed realtime voltage measurement is proposed to regulate the rate and amount of material removed. The proposed method is based on the assumption that the volume of the workpiece removed in a single discharge pulses is nearly constant. The discharge pulses are monitored and controlled to regulate the amount of material removed. For this purpose, we developed an algorithm and apparatus for counting the number of discharge pulses. Electrode wear compensation using pulse number information was applied to EDM milling in a microfactory, in which a slight tilt of the workpiece may occur. The proposed control method improves the machining quality and efficiency by eliminating the inaccuracies caused by electrode wear and workpiece tilt.

Measurement of Sub-micrometer Features Based on The Topographic Contrast Using Reflection Confocal Microscopy

  • Lee SeungWoo;Kang DongKyun;Yoo HongKi;Kim TaeJoong;Gweon Dae-Gab;Lee Suk-Won;Kim Kwang-Soo
    • Journal of the Optical Society of Korea
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    • v.9 no.1
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    • pp.26-31
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    • 2005
  • We describe the design and the implementation of video-rate reflection confocal scanning microscopy (CSM) using an acousto-optical deflector (AOD) for the fast horizontal scan and a galvanometer mirror (GM) for the slow vertical scan. Design parameters of the optical system are determined for optimal resolution and contrast. The OSLO simulations show that the performances of CSM are not changed with deflection angle and the wavefront errors of the system are less than 0.012λ. To evaluate the performances of designed CSM, we do a series of tests, measuring lateral and axial resolution, real time image acquisition. Due to a higher axial resolution compared with conventional microscopy, CSM can detect the surface of sub-micrometer features. We detect 138㎚ line shape pattern with a video-rate (30 frm/sec). And 10㎚ axial resolution is archived. The lateral resolution of the topographic images will be further enhanced by differential confocal microscopy (DCM) method and computational algorithms.

Tracking Moving Object using Hausdorff Distance (Hausdorff 거리를 이용한 이동물체 추적)

  • Kim, Tea-Sik;Lee, Ju-Shin
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.37 no.3
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    • pp.79-87
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    • 2000
  • In this paper, we propose a model based moving object tracking algorithm In dynamic scenes To adapt shape change of the moving object, the Hausdorff distance is applied as the measurement of similarity between model and image To reduce processing time, 2D logarithmic search method is applied for locate the position of moving object Experiments on a running vehicle and motorcycle, the result showed that the mean square error of real position and tracking result is 1150 and 1845; matching times are reduced average 1125times and 523 times than existing algorithm for vehicle image and motorcycle image, respectively It showed that the proposed algorithm could track the moving object accurately.

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An Experimental Study on the Fire Monitoring System for Tunnel Using SMA and Fiber Optic Cable (형상기억합금과 광케이블을 이용한 터널의 화재감지 시스템 개발에 관한 실험적 연구)

  • Hwang, Ji-Hyun;Park, Ki-Tae;Lee, Kyu-Wan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.5
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    • pp.128-134
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    • 2014
  • Recently, design and construction of street tunnels tend to focus on cost reduction and preservation of nature. Accordingly, research is actively being carried out to quickly detect fires when they occur in tunnels, which have partially closed structures. Among such research, fire detection methods using optical fiber sensors have a wide bandwidth and fast transmission speed, while using light as a medium. Therefore, it does not receive electrical interference and there is almost no loss of information during transmission, while also having little noise as well. In relation to this, a fire monitoring system that can accurately detect the location of fires in real time using shape memory alloy and optical cables was developed in this study. In order to verify the developed method, light loss measurement test was conducted according to indoor temperature changes, while also conducting fire simulation tests by installing test beds in common underground zones with different external environments of temperature and distance. Upon carrying out experiments, the fire monitoring system developed in this study was found to be able to detect fires in long distance sections in real time.

Assessment of Yield Characteristics of Gas Pipeline Materials by Observing Surface-Local Deformation (미소 표면변형 관찰을 통한 가스배관 부재의 항복특성 평가)

  • Lee, Yun-Hee;Baek, Un-Bong;Cheong, In-Hyeon;Nahm, Seung-Hoon;Lee, Sang-Houck
    • Journal of the Korean Institute of Gas
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    • v.12 no.2
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    • pp.92-98
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    • 2008
  • A combination of the instrumented indentation and 3D morphology measurement has been tried in order to perform a real-time property measurement of degraded materials in gas pipelines; three-dimensional indent morphologies were recorded using a reflective laser scanner after a series of insturmented indentations on three metallic specimens. Dimensions of the permanent deformation zone and contact boundary were analyzed from the cross-sectional profile over an remnant indent and used for estimating yield strength and hardness, respectively. Estimated yield strength was comparable with that from uniaxial tensile test and actual hardness implying material pile-up effects was lower than the calculated value from indentation curve by $20{\sim}30%$. It means that this 3D image analysis can explain the material pile-up effects on the contact properties. Additionally, a combined system of indentation and laser sensor was newly designed by modifying a shape of the indentation loading fixture.

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A Study on Improving the Position Accuracy of the Magnetic North used in Surveillance Imaging Equipments (통합형 구조의 감시정찰 영상장비에서 자북의 위치 정확도 개선에 관한 연구)

  • Shin, Young-Don;Lee, Jae-Chon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.4
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    • pp.219-228
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    • 2013
  • The surveillance imaging equipments are functioning to observe the shape of the target in real time or to measure its location precisely. The roles of such equipments are becoming more important in today's weapon systems.The aforementioned imaging equipments can be classified based on the modes of operations such as fixed, installed on cars, or composite of those. Also, according to different concepts of sensor operation, a separate type uses independent housing for each sensor whereas in a composite type a set of multiple sensors are housed into a unit altogether. The sensors in general have magnetism, thereby introducing the possible negative effects, particularly in the composite types, in locating the reference position, which is carried out by the digital compass. The use of shielding material/housing could be an option but results in increased weight and reduced portability, restricting its use in composite type equipments. As such, the objective of this paper is to study on how to reduce such magnetic effects on the position location. To do so, in the absence of magnetic shielding, a variety of sensor positions were first modeled. By combing the result with the fact that the functions of PAN & Tilt are used in the equipments, a new position location algorithm is proposed. The use of the new algorithm can automate the position location process as compared to the manual process of the existing approach. In the algorithm developed, twelve locations are measured in connection with both the azimuth and elevation angles in comparison to the six locations alone around the azimuth angle. As a result, it turns out that the measurement range has been widened but the measurement time reduced. Also, note that the effect of errors the operators may make during measurement could be reduced.

Analysis of Bioimpedance Change and the Characteristics of Blood Pressure according to Posture (자세에 따른 생체임피던스 변화와 혈압 특성 분석)

  • Cho, Young Chang;Kim, Min Soo
    • Journal of Korea Society of Industrial Information Systems
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    • v.19 no.5
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    • pp.25-31
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    • 2014
  • Bioelectrical Impedance Analysis(BIA) is a widely used method for estimating body composition changes which is a non-invasive, inexpensive, safety and reproductive method. We studied the bioimpedance change and the distinction of blood pressure according to body posture and conducted three kinds of experiments: the real-time bioimpedance measurement, the simulation using equivalent circuit model and the blood pressure measurement. Bioimpedance is measured during 4 minutes at the multi-frequency(1 kHz, 10 kHz, 20 kHz, 50 kHz, 70 kHz, 100 kHz). From the experiment results, the changes in body postures result in changes of resistance and reactance, with an average rapid increase of body impedance when going from standing, sitting to supine. Specially, the laying resistance on average was 16.49% higher than supine resistance at 50 kHz and the laying reactance measurement was also 26.05% higher than sitting reactance at 1 kHz. Blood pressure in standing posture was higher than those in other postures both in maximum($125.14{\pm}12.30$) and in minimum($75.57{\pm}10.31$). The results of BIA and blood pressure in this study will be contributed to the research on acute illness, extreme fat, and body shape abnormalities.

Displacement Measurement of a Floating Structure Model Using a Video Data (동영상을 이용한 부유구조물 모형의 변위 관측)

  • Han, Dong Yeob;Kim, Hyun Woo;Kim, Jae Min
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.2
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    • pp.159-164
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    • 2013
  • It is well known that a single moving camera video is capable of extracting the 3-dimensional position of an object. With this in mind, current research performed image-based monitoring to establish a floating structure model using a camcorder system. Following this, the present study extracted frame images from digital camcorder video clips and matched the interest points to obtain relative 3D coordinates for both regular and irregular wave conditions. Then, the researchers evaluated the transformation accuracy of the modified SURF-based matching and image-based displacement estimation of the floating structure model in regular wave condition. For the regular wave condition, the wave generator's setting value was 3.0 sec and the cycle of the image-based displacement result was 2.993 sec. Taking into account mechanical error, these values can be considered as very similar. In terms of visual inspection, the researchers observed the shape of a regular wave in the 3-dimensional and 1-dimensional figures through the projection on X Y Z axis. In conclusion, it was possible to calculate the displacement of a floating structure module in near real-time using an average digital camcorder with 30fps video.

A study on correlation between frictional coefficients and subjective evaluation while rubbing cosmetic product on skin (화장품을 바를 때 피부 마찰계수의 변화와 주관적인 평가와의 상관관계 연구)

  • Kwon Young-Ha;Kwon Hyun-Joon;Rang Moon-Jeong;Lee Su-Min
    • Science of Emotion and Sensibility
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    • v.8 no.4
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    • pp.385-391
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    • 2005
  • A frictional coefficients of in-vivo skin characteristic is the most important factor of the cutaneous mechanical properties ant the method of evaluating skin care in the fields of cosmetics products. In-vivo skin characteristic varies in many different ways depends on what is applied to the skin, loading condition, shape, surface roughness, and material of the probe. In this research, we designed a system which can be measured frictional coefficients of a human skin on real time. It consists of multi-components load-cell, actuator, linear motor and arm fixator. This measurement system was automatically controlled by computer. We measured frictional coefficients between probe an4 skin using this system ant inquired adjectives for subjective evaluation while rubbing cosmetic product on skin. Lastly, we analyzed correlation between two factors by calculating Pearson Correlation Coefficient. As a result, we could know that frictional coefficients varied from 0.17-1.2 according to cosmetic products, normal forte, materials and surface conditions of probe. We also confirmed sensual feelings of cosmetic products have close correlation with frictional coefficients.

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