• International Journal of Automotive Technology
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• v.6 no.1
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• pp.9-14
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• 2005

An experimental investigation has been carried out to reveal the atomization process of the diesel fuel spray. The spray injected through a single hole nozzle was taken by a camera on the opposite side of a stroboscope for macroscopic observation or a nanolite for microscopic observation. The effect of nozzle aspect ratio was analyzed with disintegration phenomena of the diesel spray. Based on the enlarged spray photograph, atomization process was observed in detail and further the spray cone angle was measured under various ambient pressures. The result shows that atomization of diesel spray in early stage of injection is mainly progressed in the vicinity of spray periphery region except the region close to the nozzle exit and spray head region. The spray cone angle is nearly constant under the pressurized condition, while it decreases with elapsing time under the atmospheric condition.

• Journal of ILASS-Korea
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• v.1 no.1
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• pp.85-91
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• 1996

This experiment was undertaken to investigate spray characteristics of the conventional inject ion system and the ultrasonic energy added inject ion system. Sauter mean diameter was mesured under the variation of inject ion pressure and the spray distance. To measure the droplet size we used the Malvern system 2600C. The spray angle and mass distribution was analyzed to the CCD camera and the patternater. After experiment, it was found that the ultrasonic energy added injection system had smaller sauter men diameter of droplet, wider mass distribution and wider spray angle than the conventional inject ion system had.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.36-43
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• 2002

The characteristics of spray has much effect on performance and emissions for automobile, diesel engine, gas turbine and combustion engines. So spray behavior after impinging the wall is very important for prediction the engine performance. This studies examined about impingement spray considering ambient density(18,24,30kg/ms), temperature(293,473K), impingement angle(0,30,45°). The images of impingement spray were obtained by the high speed video camera. After that we analyzed impingement spray characteristics to use this images. In this experiment, we found that 1) The spray width is reduced by increasing the ambient gas density and temperature,2) The growth of downstream is increased by increasing the impingement angle.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.537-540
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• 2005

The attitude control, sensors and camera installed on the spacecraft should be located according to the system alignment requirement. The alignment measurement requirement accuracy for the sensors should be below $\pm$0.1. Therefore, Alignment Measurement System which is combined theodolite, Rotating table and digital inclinometer etc., should be used. As the measurement accuracy is required very precise, the appropriate measurement procedure and alignment angle measurement, calculation and shimming work should is accomplished. Consequently, this paper is accomplished the works to align the measurement requirement accuracy throughout alignment measurement and shimming work of installed module and sensor

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.335-338
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• 2004

In this study has developed analysis system for automatic inspection of FPD(Flat Panel Display) characteristic, such as brightness, view angle, color ratio in the manufacturing process. Developed system consists of inspection-sensor part, acquiring a data by 3-CCD Color CCD camera and Inspection-stage part, driving a FPD holder to rotation and tilt direction. In experiment results, we could have ensured easily brightness distribution, available view angle, color reproduce and could expect to improve the quality, productivity, and yield.

• Journal of the korean Society of Automotive Engineers
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• v.12 no.5
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• pp.76-84
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• 1990

To study diesel fuel spray behavior, an experimental study was undertaken to investigate injection characteristics in vary ing back pressure and atomization mechanism in a non-evaporating diesel spray. Generally, injection characteristics is the curve of fuel flow plotted against time. The area under this curve is equal to the total quantity of fuel discharged for one injection. The method that measures rate of injection is long tube-type fuel rate indicator. Diesel spray injected into a quiescent gaseous environment under high pressure is observed by taking high speed camera by the focused shadow photographs. The results show that, at the start of injection, as the injected fuel rushes into the quiescent atmosphere the spray angle becomes large. Finally the spray stabilizes at a constant cone angle. Spray penetration length increases with the injection pressure.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.299-301
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• 1996

Since a standard lens has small sight angle, a fish-eye lens can be used in order to obtain wide sight angle for the robot vision system. In spite of the advantage, the image through the lens has variable resolution; the central information of the lens is of high resolution, but the peripheral information is of low resolution. Owing to this difference of resolution, the variable resolution image should be transformed to a uniform resolution image in order to determine the positions of the objects in the image. In this work, the correction method for the distorted image is presented and the performance is analyzed. Furthermore, the camera with a fish eye lens can be used to determine the real world coordinates. The performance is shown through experiments.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.373-375
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• 2008

In this paper the arc behavior in spiral type vacuum interrupter was analyzed by observing taken photographs from high-speed digital camera(10000frame/second) and current-voltage waveform from oscilloscope. As a result, the influence of twisting angle between contacts on arc behavior could be analyzed by matching and comparing arc voltage and photographs simultaneously.

• Journal of ILASS-Korea
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• v.21 no.1
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• pp.13-19
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• 2016

Atmospheric spray characteristics were experimentally compared between liquid-gas and liquid-liquid sprays of a pintle injector. In order to study spray characteristics, water and air were used as the simulants and the visualization technic was adopted. Spray images were acquired by using a backlight method by a high-resolution CMOS camera. As a result, when the pintle opening distance increased, liquid sheets became unstabled and fluttering droplets increased. In the liquid-gas case, the breakup performance increased as the pressure of gas injected from the annular orifice increased. In the liquid-liquid case, atomization efficiency decreased as the pressure of liquid injected from the annular orifice increased. Spray angles presented a similar trend between two cases. At the same momentum ratio, the spray angle of liquid-liquid case was lower than the angle of liquid-gas case.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.3
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• pp.597-602
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• 2013

In this paper, the lens module of mega pixel type was designed for barrel distortion calibration due to the barrel distortion of ultra wide angle. And the performance of this camera module was improved with the images from wide dynamic range 2 megapixel CMOS image sensor.