• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.206-211
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• 2002

The aim of this study was to obtain the basic data on the fish school behavior change to approaching vessel and fish species identification by means of their swimming speed. The surveys were carried out for the juvenile southern blue fin tuna and other fish schools off Esperance, western Australia from January to March 1999. We observed changes of fish school behavior in response to the approaching vessel using 360-degree scanning sonar. The results showed that, a horizontal direction index used to quantify a change of fish school behavior did not identify dependence of a radial distance and a swimming speed. A Mann­Whitney test conducted using the horizontal swimming speed of both species identified by sonar specialists, did not reveal a significant difference.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1380-1383
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• 2004

The scanning type XY stage is frequently used these days as precision positioning system in equipment for semiconductor or display element. It is requested higher velocity and more precise accuracy for higher productivity and measuring performance. The position accuracy of general stage is primarily affected by the geometric errors caused by parasitic motion of stage, misalignments such as perpendicular error, and thermal expansion of structure. In the case of scanning type stage, H type frame is usually used as base stage which is driven by two actuators such as linear motor. In the point view of scanning process, the stage is used in moving motion. Therefore, dynamic variation is added as significant position error source with other parasitic motion error. Because the scanning axis is driven by two actuators with two position detectors, 2 dimensional position errors have different characteristic compared to general tacked type XY stage. In this study 2D position error of scanning stage is analyzed by 1D heterodyne interferometer calibrator, which can measure 1D linear position error, straightness error, yaw error and pitch error, and perpendicular error. The 2D position error is evaluated by diagonal measurement (ISO230-6). The yaw error and perpendicular error are compensated on the base stage of scanning axis. And, the horizontal straightness error is compensated by cross axis compensation. And, dynamic motion error in scanning motion is analyzed.

• 대한의용생체공학회:의공학회지
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• 제16권1호
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• pp.43-48
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• 1995

A high speed optic scanner capable of 16 frames/sec imaging has been developed for the realization of the infrared thermal Imaging system with a single element infrared sensor. The high speed optic scanner is composed of a rotating polygon mirror for horizontal scanning, a flat mirror mounted on a galvanometer for vertical scanning, and a spherical mirror. It has been experimentally found that the optic scanner is capable of 16 framesllsec imaging with the frame matrix size of 256 x 64.

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

• Restorative Dentistry and Endodontics
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• 제16권2호
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• pp.43-61
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• 1991

Present - day inlay casting procedures have been developed for more than 100 years and experimentation has focused on the perfect adaptation to the cavity preparation. Marginal adaptation is considered to be an important indicator of the acceptability of the cast restotration, especially on the gingival margin. The purpose of this study was to evaluate the effects of a dissecting microscope and burnishing on vertical discrepancies, horizontal discrepancies, and cement thicknesson master die. Extracted premolars were prepared for class II gold inlays and master dies were made with conventional techniques. The experiments consisted of 4 groups. Group 1 : unaided eye, no burnishing on master die. Group 2 : unaided eye, burnishing on master die. Group 3 : microscope, no burnishing on master die. Group 4 : microscope, burnishing on master die. Cemented inlays were embedded in the hard resin and sectioned with microcutter through the gingival margins. The sectioned surfaces were polished with emery paper and finally with aluminum oxide powders. The results of the experiments were measured for vertical discrepancies, horizontal discrepancied and cement thickness under the scanning electron microscpe at the beveled gingival margin. The results of the study were summarized as follows. 1. Group 1 showed the vertical discrepancies of $81.6{\mu}m({\pm}48.6{\mu}m)$, horizontal discrepancies of $60.1{\mu}m({\pm}41.1{\mu}m)$, and cement thickness of $59.6{\mu}m({\pm}24.6{\mu}m)$. 2. Group 2 showed the vertical discrepancies of $78.6{\mu}m({\pm}30.9{\mu}m)$, horizontal discrepancies of $36.9{\mu}m({\pm}20.7{\mu}m)$, and cement thickness of $54.0{\mu}m({\pm}21.6{\mu}m)$. 3. Group 3 showed the vertical discrepancies of $57.5{\mu}m({\pm}26.4{\mu}m)$, horizontal discrepancies of $28.4{\mu}m({\pm}17.5{\mu}m)$, and cement thickness of $37.2{\mu}m({\pm}17.4{\mu}m)$. 4. Group 4 showed the vertical discrepancies of $56.7{\mu}m({\pm}35.0{\mu}m)$, horizontal discrepancies of $31.8{\mu}m({\pm}24.2{\mu}m)$, and cement thickness of $45.6{\mu}m({\pm}19.8{\mu}m)$. 5. Vertical discrepancies were not significantly different at any groups(p>.050). 6. Microscope groups(Group 3, 4) showed significantly improved horizontal marginal adaptation (p<.050). 7. Although cement thickness showed the subset of Group 3. 4, 2 and Group 4, 2, 1. Group 3 showed significantly smaller thickness than Group l(p<.050). 8. Finishing and polishing by means of a microscope produced significantly smaller discrepancies than doing so with the unaided eye(p<.050).

• Applied Microscopy
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• 제50권
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• pp.25.1-25.11
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• 2020

Scanning acoustic microscopy (SAM) or Acoustic Micro Imaging (AMI) is a powerful, non-destructive technique that can detect hidden defects in elastic and biological samples as well as non-transparent hard materials. By monitoring the internal features of a sample in three-dimensional integration, this technique can efficiently find physical defects such as cracks, voids, and delamination with high sensitivity. In recent years, advanced techniques such as ultrasound impedance microscopy, ultrasound speed microscopy, and scanning acoustic gigahertz microscopy have been developed for applications in industries and in the medical field to provide additional information on the internal stress, viscoelastic, and anisotropic, or nonlinear properties. X-ray, magnetic resonance, and infrared techniques are the other competitive and widely used methods. However, they have their own advantages and limitations owing to their inherent properties such as different light sources and sensors. This paper provides an overview of the principle of SAM and presents a few results to demonstrate the applications of modern acoustic imaging technology. A variety of inspection modes, such as vertical, horizontal, and diagonal cross-sections have been presented by employing the focus pathway and image reconstruction algorithm. Images have been reconstructed from the reflected echoes resulting from the change in the acoustic impedance at the interface of the material layers or defects. The results described in this paper indicate that the novel acoustic technology can expand the scope of SAM as a versatile diagnostic tool requiring less time and having a high efficiency.

• 감성과학
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• 제17권2호
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• pp.111-122
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• 2014

본 연구는 지하철 로비공간을 대상으로 한 주시실험을 통해 공간정보의 본능적 시선탐색과정에서 나타나는 주시특성에 나타난 주사경로 알고리즘을 분석하였다. 주시기간 구간별 분석에서 주시시간이 오래 경과할수록 주사유형 횟수가 증가하고 있었는데, 오래 주시할수록 주시단절이 많이 일어난 것으로 해석이 가능하며, 주시에 따른 피로나 활발한 탐색이 자연스러운 공간탐색과정에서 일어나는 과정에서 화상범위를 벗어나는 경우가 많았던 것으로 보인다. 또한 시간구간의 변화에 따른 주사유형의 변화를 추세선으로 살펴본 결과, "집중"은 시간구간의 증가와 함께 가파른 증가, "대각 수직"은 완만한 증가를 보이는 반면, "순환 혼합 수평"은 감소 경향을 보이고 있다. 공간을 주시한 피험자의 주시데이터에는 다양한 시각정보가 포함되어 있는데, "주의집중"에 나타난 주사유형을 분석한 결과, 이상과 같은 의미 있는 결론을 도출할 수 있었다. 이러한 주사유형의 증감특성은 시간의 경과에 따른 주사경향을 파악함에 있어 기초자료가 될 수 있다.

• 센서학회지
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• 제27권2호
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• pp.137-141
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• 2018

Detecting the ego-lane of a vehicle (the lane on which the vehicle is currently running) is one of the basic techniques for a smart car. Vision sensing is a widely-used method for the ego-lane detection. Existing studies usually find road lane lines by detecting edge pixels in the image from a vehicle camera, and then connecting the edge pixels using Hough Transform. However, this approach takes rather long processing time, and too many straight lines are often detected resulting in false detections in various road conditions. In this paper, we find the lane lines by scanning only a limited number of horizontal lines within a small image region of interest. The horizontal image line scan replaces the edge detection process of existing methods. Automatic thresholding and spatiotemporal filtering procedures are also proposed in order to make our method reliable. In the experiments using real road images of different conditions, the proposed method resulted in high success rate.

• 전기학회논문지
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• 제57권10호
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• pp.1876-1882
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• 2008

Nano manipulator is used to manufacture Carbon NanoTube(CNT) tips. Using nano manipulator, operator attaches a CNT at the apex of Atomic Force Microscope(AFM) tip, which requires a mastery of mechanics and long manufacture time. Nano manipulator is installed inside a Scanning Electron Microscope(SEM) chamber to observe the operation. This paper presents a control scheme for horizontal axes of nano manipulator via processing SEM image. Edges of AFM tip and CNT are first detected, and the position information so obtained is fed to control horizontal axes of nano manipulator. That is, a visual servoing loop is realized to control the axes more precisely in nano scale.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.409-412
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• 2001

This paper decides provision of brightness by average value of horizontal pixel, vertical pixel association. Give weight at association value calculation to improve diagonal line characteristics, and applied method to add average of vertical pixel and average of diagonal line pixel at interpolation. Therefore it improves PSNR, and it proposed algorithm that improve horizontal outline and vortical outline characteristics in big area of luminance contrast. It changed scanning line of serial scan based on proposed algorithm and designed variable image system for efficient data transmission through PCI interface circuit.