• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.268-272
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• 1996

Error correction effect for maladjusted stereo cameras with calibrated pixel distance parameter is presented. The camera calibration is a necessary procedure for stereo vision-based depth computation. Intra and extra parameters should be obtain to determine the relation between image and world coordination through experiment. One difficulty is in camera alignment for parallel installation: placing two CCD arrays in a plane. No effective methods for such alignment have been presented before. Some amount of depth error caused from such non-parallel installation of cameras is inevitable. If the pixel distance parameter which is one of intra parameter is calibrated with known points, such error can be compensated in some amount. Such error compensation effect with the calibrated pixel distance parameter is demonstrated with some experimental results.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.23-27
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• 2002

Two $^{192}$ Ir HDR brachytherapy sources were calibrated with a Farmer ionization chamber in air method and in a PMMA cylindrical phantom. The calibration air method used ionization chamber with buildup cap, and 8 variation distances for center-to-center of the source to chamber. In the optimum distance the measured activity, especially for the high activity source, deviation was 0.3% from the activity provided by manufacturer. Calibration with a PMMA cylindrical phantom was less sensitive, and suitable for quick check method with accuracy less than 10%.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1828-1831
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• 1997

this paper, to represent the robot motion approximately in space, delas with algorithm for position recognition of space robot, target and obstacle with vision system in 2-D. And also there are algorithms for precise distance-measuring and calibration usign laser displacement system, and for trajectory selection for optimizing moving to object, and for robot locomtion with air-thrust valve. And the software synthesizing of these algorithms hleps operator to realize the situation certainly and perform the job without any difficulty.

• Journal of Radiation Protection and Research
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• v.22 no.1
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• pp.29-33
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• 1997

Neutron room scattering corrections that should be made when neutron detectors are calibrated with a $D_2O$ moderated $^{252}Cf$ neutron source in the center of a calibration room are considered. Such room scattering corrections are dependent on specific neutron source type, detector type, calibration distance, and calibration room configuration. Room scattering corrections for the responses of a thermoluminescence dosimeter and two different types of spherical detectors to neutron source in the Radiation Calibration Laboratory(RCL) neutron calibration facility at the Korea Atomic Energy Research Institute(KAERI) were experimentally determined and are presented. The measured room scattering results are then compared with theoretical results calculated by predicting room scattering effects in terms of parameters related to the specific configuration. Agreement between measured and calculated scattering correction is generally about 10% for three kinds of detectors in the calibration facility.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.2
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• pp.88-92
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• 2011

This paper looks at the development of the visual system of robots, and the development of image processing algorism to measure the size of an object and the distance from robot to an object for the visual system. Robots usually get the visual systems with a camera for measuring the size of an object and the distance to an object. The visual systems are accurately impossible the size and distance in case of that the locations of the systems is changed and the objects are not on the ground. Thus, in this paper, we developed robot's visual system to measure the size of an object and the distance to an object using two cameras and two-degree robot mechanism. And, we developed the image processing algorism to measure the size of an object and the distance from robot to an object for the visual system, and finally, carried out the characteristics test of the developed visual system. As a result, it is thought that the developed system could accurately measure the size of an object and the distance to an object.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.601-603
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• 2004

Multi-Spectral Camera(MSC) is a payload on the KOMPSAT -2 satellite to perform the earth remote sensing. The instrument images the earth using a push-broom motion with a swath width of 15 km and a ground sample distance (GSD) of 1 m over the entire field of view (FOV) at altitude 685 Km. The instrument is designed to have an on-orbit operation duty cycle of $20\%$ over the mission lifetime of 3 years with the functions of programmable gain! offset and onboard image data compression/storage. MSC instrument has one(1) channel for panchromatic Imaging and four(4) channel for multi-spectral Imaging covering the spectral range from 450nm to 900nm using TDI CCD Focal Plane Array (FPA). In this paper, the configuration, the interface of MSC hardware and the MSC operation concept are described. And the method of the MSC calibration are described and the design of MSC calibration operation to measure the change of MSC after Launch & Early Operation(LEOP) and normal mission operations are discussed and analyzed.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3833-3840
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• 2022

A method for calibrating the energy scale and detection efficiency of stilbene scintillators is presented herein. This method can be used to quantitatively analyze the Compton continuum of gamma-ray spectra obtained using such scintillators. First, channel-energy calibration was conducted by fitting a semi-empirical equation for the Compton continuum to the acquired energy spectrum and a new method to evaluate the intrinsic detection efficiency, called intrinsic Compton efficiency, of stilbene scintillators was proposed. The validity of this method was verified by changing experimental conditions such as the number of sources being measured simultaneously and the detector-source distance. According to the energy calibration, the standard error for the estimated Compton edge position was ±1.56 keV. The comparison of the intrinsic Compton efficiencies calculated from the single- and two-source spectra showed that the mean absolute difference and the mean absolute percentage difference are 0.031 %p and 0.557%, respectively, demonstrating reasonable accuracy of this method. The feasibility of the method was confirmed for an energy range of 0.5-1.5 MeV, showing that stilbene scintillators can be used to quantitatively analyze gamma rays in mixed-radiation fields.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1227-1232
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• 1998

The frequency response on the tip-sample distance in scanning electrochemical microscopy (SECM) that is combined with an electrochemical quartz crystal microbalance (EQCM) is described. The oscillation frequency of the EQCM increases rapidly when the SECM tip is very close to the substrate electrode surface. This frequency increase is reproducible regardless of the current feedback in SECM, which is attributed to the stress caused by the tip pressing the quartz crystal. It is useful to calibrate the tip-sample distance with respect to the frequency change when a combined system of SECM and EQCM (SECM-EQCM) is used. This method could be applied to several cases such as rigid metal electrode and non-conducting or partially conducting polymer coating prepared on the quartz crystal regardless of the feedback current.

• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.165-170
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• 2002

This study was carried out to measure the 3D-distance of a cow model teat for an application possibility on Robotic Milking System(RMS). A teat recognition algorithm was made to find 3D-distance of the model by using Gonzalrez's theory. Some of the results are as follows. 1 . In the distance measurement experiment on the test board, as the measured length, and the length between the center of image surface and the measured image point became longer, their error values increased. 2. The model teat was installed and measured the error value at the random position. The error value of X and Y coordinates was less than 5㎜, and that of Z coordinates was less than 20㎜. The error value increased as the distance of camera's increased. 3. The equation for distance information acquirement was satisfied with obtaining accurate distance that was necessary for a milking robot to trace teats, A teat recognition algorithm was recognized well four model cow teats. It's processing time was about 1 second. It appeared that a teat recognition algorithm could be used to determine the 3D-distance of the cow teat to develop a RMS.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.8
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• pp.178-184
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• 2014

In this study, we develop liquid density sensor by measuring of balanced position between gravity and bouyancy, corresponding to liquid density, using distance measuring by magnetostriction technology. For improvement of accuracy of liquid density sensor system. And we derive the related equation between liquid density and moving distance of density sensor, and make the calibration method for liquid density sensor by magnetostriction technology. Using fabricated liquid density sensing system and derived equation, have measured the density of several liquids. And compare it to measuring results using Oscillating U-tube type high accuracy density meter, having 0.000001 g/cc resolution. The deviation of results between two density measuring systems was less than 0.001 g/cc.