• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.247.2-247.2
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• 2014

플라즈마 전파 속도와 전자 온도를 조사하기 위해 ICCD카메라(Intensified Charge-Coupled Device Camera, 이하 ICCD)를 이용하여 대기압 저온 플라즈마제트의 방전 이미지를 촬영하였다. 사용된 플라즈마 제트 장치는 유리관 안에 주사기 바늘형 전극이 들어있는 형태이다. 전극의 내경은 1.3 mm, 외경은 1.8 mm, 총 길이는 39.0 mm이며 재질은 스테인레스강이다. 유리관의 내경은 2.0 mm, 외경은 2.4 mm, 총 길이는 80.0 mm이다. 입력 전압은 3.0 kV이며 구동 주파수는 40 kHz이다. 아르곤과 질소의 혼합가스 비율은 각각 100:1, 98:2, 95:5을 사용하였으며 총 가스유량은 400 sccm이다. 각각의 비율별로 군속도는 267 km/s, 305 km/s, 313 km/s이며 이온 음향 속도는 1.16 km/s, 1.24 km/s, 1.25 km/s이고, 전자 온도는 0.55 eV, 0.63 eV, 0.65 eV로 관찰되었다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.270-278
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• 2000

A machine vision system using charge coupled device(CCD) camera for the weed detection in a radish farm was developed. Shape features were analyzed with the binary images obtained from color images of radish and weeds. Aspect, Elongation and PTB were selected as significant variables for discriminant models using the STEPDISC option. The selected variables were used in the DISCRIM procedure to compute a discriminant function for classifying images into one of the two classes. Using discriminant analysis, the successful recognition rate was 92% for radish and 98% for weeds. To recognize radish and weeds more effectively than the discriminant analysis, an artificial neural network(ANN) was used. The developed ANN model distinguished the radish from the weeds with 100%. The performance of ANNs was improved to prevent overfitting and to generalize well using a regularization method. The successful recognition rate in the farms was 93.3% for radish and 93.8% for weeds. As a whole, the machine vision system using CCD camera with the artificial neural network was useful to detect weeds in the radish farms.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.27-37
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• 1993

In unmanned machining, One of the most essential issue is the tool management system which includes controlling. identification, presetting and monitoring of cutting tools. Especially the monitoring of tool wear and fracture may be the heart of the system. In this study a computer vision based tool monitoring system is developed. Also an algorithm which can determine the tool condition using this system is presented. In order to enhance practical adaptability the vision system through which two modes of images are taken is located over the rake face of a tool insert. And they are analysed quantitatively and qualitatively with image processing technique. In fact the morphologies of tool fracture or wear are occurred so variously that it is difficult to predict them. For the purpose of this problem the pattern recognition is introduced to classify the modes of the tool such as fracture, crater, chipping and flank wear. The experimental results performed in the CNC turning machine have proved the effectiveness of the proposed system.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.12 no.2
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• pp.173-180
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• 1994

One can see more and more photograrmmetric applications dealing with the extraction of information from images obtained with CCD (Charge Coupled Device) camera scanners. In order for this information to be useful, the scanning errors of scanners must be known through a calibration. Investigation of this study is given to the detailed procedure of the correction for scanning errors created during the scanning of photographs with CCD camera scanner using the three kinds of high resolution reseal plates prepared. The geometric corrected digital images for scanning errors were generated and the accuracy of the resulting new images for each types of plates were checked comparing its image coordinates with there corresponding ground coordinates for the check points.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.98-99
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• 2012

Deposition of thin films using magnetron sputtering plasmas is a well-developed, classical technology. However, detailed investigations using advanced diagnostics are insufficient in magnetron sputtering, in comparison with plasma-aided dry etching and plasma-enhanced chemical vapor deposition. In this talk, we will show examples of diagnostic works on magnetron sputtering employing metal targets. Diagnostic methods which have fine spatial resolutions are suitable for magnetron sputtering plasmas since they have significant spatial distributions. We are using two-dimensional laser-induced fluorescence spectroscopy, in which the plasma space is illuminated by a tunable laser beam with a planer shape. A charge-coupled device camera with a gated image intensifier is used for taking the picture of the image of laser-induced fluorescence formed on the planer laser beam. The picture of laser-induced fluorescence directly represents the two-dimensional distribution of the atom density probed by the tunable laser beam, when an intense laser with a relatively wide line-width is used. When a weak laser beam with a relatively narrow linewidth is used, the laser-induced fluorescence represents the density distribution of atoms which feel the laser wavelength to be resonant via the Doppler shift corresponding to their velocities. In this case, we can obtain the velocity distribution function of atoms by scanning the wavelength of the laser beam around the line center.

• Journal of Animal Science and Technology
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• v.62 no.2
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• pp.276-291
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• 2020

This study was conducted to investigate behavioral changes in laying hens (Hy-Line Brown) after transfer to a multi-tier system from the floor system and to examine their production performance. The hens were randomly divided into two groups and were allocated to the multi-tier system and the floor system at a commercial farm. Behavior of the laying hens was recorded by CCD (charge-coupled device) cameras and a digital video recorder. The data were scanned every 2 min to obtain an instantaneous behavioral sample or were immediately counted whenever the hens exhibited a designated behavior. Behavior changed dramatically during the first seven days. Egg production was higher in the multi-tier system, while cracked and dirty eggs were more frequent in the floor system (p < 0.05). No differences in mortality rate or egg quality were observed between the groups. In conclusion, the hens needed at least seven days to adapt to the multi-tier system. The multi-tier system was more efficient than the floor system in terms of production performance.

• Applied Microscopy
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• v.39 no.1
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• pp.79-83
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• 2009

We report a useful method to estimate the electron dose rate which may be a decisive factor to characterize sample properties. Even though most mircoscopes have their own exposure meters, there are several practical concerns when such exposure meters are used to measure the electron dose rate: 1) Specimen should be avoided within the entire area of exposure meter; 2) beam current has to be always recorded whenever the operation mode is changed; 3) the electron dose rate can not be calculated for the beam current beyond the detectable range. To overcome these limitations, we suggest a useful method which utilize a CCD (charge coupled device) camera which is now a popular detector to obtain the final electron micrographs. We have evaluated the CCD sensitivity using the linear relationship between electron current on the exposure meter and counter ratio on the CCD camera which are built in KBSI-HVEM (high voltage electron microscope). Applying the new method, we obtained the CCD sensitivity which are approximately 0.039 counts/$e^-$ and 1.37 counts/$e^-$ for the Top-TV and the HV-GIF CCD cameras, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.10B
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• pp.1124-1132
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• 2009

We proposed a new method to improve the resolution of elemental image set in the integral imaging system using super-resolution image reconstruction method. Adjacent elemental images have same image region which is projected from the common area of object. These projected images in the elemental image can be used for low resolution images of super-resolution method. Two methods for resolution improvement of elemental image set using super-resolution method are proposed. One is super-resolution among the elemental image sets and the other is among the elemental images. Simulation results are compared with resolution improved elemental image set using interpolated method.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.4
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• pp.16-21
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• 2008

The demand for three-dimensional (3D) shape measurements is increasing in a variety of fields, including the manufacture of molds and dies. The most popular technology for 3D shape measurement is the coordinate measuring machine (CMM) with a contact trigger probe. Although a CMM provides a high degree of accuracy, it is inefficient due to its long measuring time. It also has difficulty measuring soft objects that can be deformed by the touch of the contact probe. In addition, a CMM cannot digitize areas that are difficult to reach, and cannot capture very minute details on the surface of complex parts. For these reasons, optical non-contact measurement techniques are receiving more attention since they eliminate most of the problems associated with contact methods. Laser scanning is emerging as one of the more promising non-contact measurement techniques. This paper describes various acquisition considerations for laser scanning, including the accuracy of the 3D scan data, which depends on the charge-coupled device (CCD) gain and noise. The CCD gain and noise of a 3D laser scanner are varied while keeping the other conditions constant, and the measurement results are compared to the dimensions of a standard model. The experimental results show that a considerable time savings and an optimum degree of accuracy are possible by selecting the proper CCD gain and noise.

• Journal of ILASS-Korea
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• v.23 no.1
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• pp.22-29
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• 2018

The purpose of this study is to investigate the macroscopic spray characteristics and spray pattern of a gasoline direct injection (GDI) injector according to the increase of injection pressure. The macroscopic spray characteristics, such as a spray tip penetration and spray angle, were measured and analyzed from the frozen spray images, which are obtained from the spray visualization system including the high-speed camera, light-source, long-distance microscope (LDM). The spray pattern was analyzed through the deviation of the center of the spray plum and images were acquired using Nd: YAG Laser and ICCD(Intensified charge coupled device) camera. From the experiment and analysis, it revealed that the injection pressure have a significant influence on the spray tip penetration and spray pattern. However, the injection pressure have little influence on the spray angle. The increase of injection pressure induced the reduction of a closing delay. In addition, the deviation of spray center increase with the increase of injection pressure and the distance from a nozzle tip.