• Journal of radiological science and technology
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• v.38 no.4
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• pp.443-449
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• 2015

An ultrasound probe has a big impact on Doppler images even though it has very high risk of frequent function-breakdowns occurring in medical ultrasound scanners. This study experimentally analyses the impacts of an ultrasonic probe's defected elements on power & color Doppler images. The results show that, the bigger the size of defected probe elements is, and the closer a group of action elements is to the center, the more the brightness of images and the velocity of Doppler diminish. When elements' defects increase in color & power Doppler images, false images are formed to be mistaken for blood-vessel plaque in neighboring regions. Accordingly, whenever element defects are suspected, we need check-up process in B-mode. From this respective, it is advisable to have primary interest in a probe and carry out continuous probe QA for ultrasonography.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.6
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• pp.10-18
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• 2010

This paper proposes an image stabilization algorithm for close watching UAV(Unmanned Aerial Vehicle) using motion separation and stabilization mode. The motion of UAV is composed of its actual navigating motion and unwanted vibrating motion so that image sequences obtained from UAV are shaken randomly. In order to stabilize these images we separate the vibrating motion component from UAV motion and remove the effect caused by it from image sequences. In the proposed algorithm the motion and global intensity change of two consecutive images are modeled with 6 motion parameters and 2 intensity change parameters respectively. These modeled parameters are estimated by non-linear least square method based on Gauss-Newton algorithm. The vibrating motion component is separated from the estimated motion using IIR filtering and the geometric deformation caused by it is removed from image sequences. In order to apply the proposed method to real aerial image sequences with many abrupt changes of camera view, we proposed a stabilizing method using two different modes named as stabilizing and non-stabilizing mode. Experimental results show that the accuracy of motion estimation is 99% and the efficiency of removing the vibrating motion component is 90%. We apply the proposed method to real aerial image sequences and verified its stabilizing performance.

• Journal of the Korean earth science society
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• v.21 no.2
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• pp.137-158
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• 2000

The correlation and Empirical Orthogonal Function (EOF) analyses over the globe have been applied to intercompare lower-stratospheric (${\sim}$70hPa) temperature obtained from satellite data and two model reanalyses. The data is the19 years (1980-98) Microwave Sounding Unit (MSU) channel 4 (Ch4) brightness temperature, and the reanalyses are GCM (NCEP, 1980-97; GEOS, 1981-94) outputs. In MSU monthly climatological anomaly, the temperature substantially decreases by ${\sim}$21k in winter over southern polar regions, and its annual cycle over tropics is weak. In October the temperature and total ozone over the area south of Australia remarkably increase together. High correlations (r${\ge}$0.95) between MSU and reanalyses occur in most global areas, but they are lower (r${\sim}$O.75) over the 20-3ON latitudes, northern America and southern Andes mountains. The first mode of MSU and reanalyses for monthly-mean Ch4 temperature shows annual cycle, and the lower-stratospheric warming due to volcanic eruptions. The analyses near the Korean peninsula show that lower-stratospheric temperature, out of phase with that for troposphere, increases in winter and decreases in summer. In the first mode for anomaly over the tropical Pacific, MSU and reanalyses indicate lower-stratospheric warming due to volcanic eruptions. In the second mode MSU and GEOS present Quasi-Biennial Oscillation (QBO) while NCEP, El Ni${\tilde{n}}$o. Volcanic eruption and QBO have more impact on lower-stratospheric thermal state than El Ni${\tilde{n}}$o. The EOF over the tropical Atlantic is similar to that over the Pacific, except a negligible effect of El Ni${\tilde{n}}$o. This study suggests that intercomparison of satellite data with model reanalyses may estimate relative accuracy of both data.

• Journal of the Korean earth science society
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• v.21 no.5
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• pp.503-524
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• 2000

Intercomparisons between four kinds of data have been done to estimate the accuracy of satellite observations and model reanalysis for middle and lower tropospheric thermal state over regional oceans. The data include the Microwave Sounding Units (MSU) Channel 2 (Ch2) brightness temperatures of NOAA satellites and the vertically weighted corresponding temperature of ECMWF GCM (1980-93). The satellite data for midtropospheric temperatures are MSU2 (1980-98) in nadir direction and SC2 (1980-97) in multiple scans, and for lower tropospheric temperature SC2R (1980-97). MSU2 was derived in this study while SC2 and SC2R were described in Spencer and Christy (1992a, 1992b). Temporal correlations between the above data were high (r${\ge}$0.90) in the middle and high latitudes, but low(r${\sim}$0.65) over the low latitude and more convective regions. Their values with SC2R which included the noises due to hydrometeors and surface emission were conspicuously low. The reanalysis shows higher correlation with SC2 than with MSU2 partially because of the hydrometeors screening. SC2R in monthly climatological anomalies was more sensitive to surface thermal condition in northern hemisphere than MSU2 or SC2. The first EOF mode for the monthly mean data of MSU and ECMWF shows annual cycle over most regions except the tropics. The mode in MSU2 over the Pacific suggests the east-west dipole due to the Walker circulation, but this tendency is not clear in other data. In the first and second modes for the Ch2 anomalies over most regions, the MSU and ECMWF data commonly indicate interannual variability due to El Ni${\tilde{n}$o and La Ni${\tilde{n}$a. The substantial disagreement between observations and model reanalysis occurs over the equatorial upwelling region of the western Pacific, suggesting uncertainties in the model parameterization of atmosphere-ocean interaction.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.9
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• pp.26-34
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• 1998

This paper presents a characterization method for faults of circuit patterns on MCM(Multichip Module) or PCB(Printed Circuit Board) substrates with electron beams of a SEM(Scanning Electron Microscope) by inducing voltage contrast on the signal line. The experimentation employes dual potential electron beams for the fault characterization of circuit patterns with a commercial SEM without modifying its structure. The testing procedure utilizes only one electron gun for the generation of dual potential electron beams by two different accelerating voltages, one for charging electron beam which introduces the yield of secondary electron $\delta$ < 1 and the other for reading beam which introduces $\delta$ > 1. Reading beam can read open's/short's of a specific net among many test nets, simultaneously discharging during the reading process for the next step, by removing its voltage contrast. The experimental results of testing the copper signal lines on glass-epoxy substrates showed that the state of open's/short's had generated the brightness contrast due to the voltage contrast on the surface of copper conductor line, when the net had charged with charging electron beams of 7KV accelerating voltages and then read with scanning reading electron beams of 2KV accelerating voltages in 10 seconds. The experimental results with Au pads of a IC die and Au plated Cu pads of BGA substrates provided the simple test method of circuit lines with 7KV charging electron beam and 2KV reading beam. Thus the characterization method showed that we can test open and short circuits of the net nondestructively by using dual potential electron beams with one SEM gun.

• Journal of Conservation Science
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• v.35 no.6
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• pp.701-708
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• 2019

Animal glue is a natural adhesive made from processed skins or bones of animals. It is widely used in wooden crafts, papercrafts, dancheong painting, and pictures. Accurate evaluation of the quality of animal glues during production and use is difficult because there is no formal method for testing the glue's properties during pretreatment and measurement conditions. Thus, in this study, a series of tests were carried out by changing the conditions of swelling, temperature, and concentration of animal glue and gelatin sold on the market. Twelve types of animal glues were evaluated, having a viscosity range of 12.67 cP to 29.43 cP. The results showed that the physical characteristics of the glues were stable when allowed to swell for six h in distilled water(23℃). When 10%(by weight in distilled water) of the animal glue was measured in the reflective mode of a spectrophotometer, the optical characteristics of the glues were stable. Powdered animal glues have a medium brightness and middle-high chroma. Relative to powdered glues, stick animal glues have a low brightness and a medium chroma. Based on the results of this study, it is expected that the data can be assembled into a form so that animal glue workers can use it as a reference for the preparation of evaluation standards for testing the characteristics of animal glues.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.1
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• pp.199-207
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• 2016

In this paper, we propose efficient smart indoor emotional lighting control system based on android platform using the biological signal. The proposed smart indoor smart emotional lighting control system were configured as the biological signal measurement device and removable smart wall pad, lighting driver, luminaire. The control system was extracts the emotional language by measured the biological signal, and it was transmitted a control signal to each lighting driver using a bluetooth in the wall pad. The lighting driver were designed to control the lighting device through an expansion board by collected control signal and the illuminance information the surrounding. In this case, the wall pad can be selecting of manual control and the bio signal mode by that indoor emotional lighting control algorithms, and it was implemented the control program that possible to partial control by selecting the wanted light. Experiment results of the proposed smart indoor emotional lighting control system, it were possible to the optional control about the luminaire of required area, and the manual control by to adjustable of color temperature with that the efficiently adjustable of lighting by to biological signal and emotional language. Therefore, were possible to effective control for improvement of concentration and business capability of indoor space business conduct by controlling the color and brightness that is appropriate for your situation. And, was reduced power consumption and dimmer voltage, lighting-current than the existing-emotional lighting control system.

• Journal of radiological science and technology
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• v.37 no.2
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• pp.117-124
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• 2014

This study has investigated the effects of the defects in the probe elements influence Doppler images in the medical ultrasonic scanners. This work was implemented that the quality of Doppler images depended on the extent and location of the probe element defected. The probe performance was rated in terms of the number of piezoelectric elements lost and this was studied in the experiment by electrical disconnection to the elements. The results showed that Doppler velocity became rapidly reduced as the defected elements encountered with the element group activated at the Doppler mode, not as the flow velocity. The effect of the probe defect is decreased when the defects occurred at the element group activated for Doppler mode, as was increased the number of the elements. It was observed that the higher the flow velocity of Doppler flow phantom is, the wider the spectrum of Doppler is. And the Doppler velocity soared up and the dispersion of image brightness is increased when the defected elements got out of the elements activated at Doppler mode. The result showed that TADVP(time-average-Doppler-velocity-profile) is decreased with the increase of the probe element defect, especilly in the region of high frequency. It is expected that the research of various defects of probe elements are needed, and this study can be practical tools for probe based ultrasonic QA in the future.

• Korean Journal of Remote Sensing
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• v.34 no.2_2
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• pp.431-437
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• 2018

We analyzed the feasibility of detecting wave gliders moving on the sea surface using SAR images. For the experiment, a model was constructed and placed on the sea using a towing ship before and after the satellite observation time. In the acquisition of KOMPSAT-5 image, high resolution SAR data of spotlight mode was collected considering the small size of wave glider. As a result of the backscattering intensity analysis around the towing ship along with wave glider, several scattering points away from the ship were observed, which are not strong but clearly distinguished from the surrounding clutter values. Considering the distance from the center of the ship, it seems to be a signal by the wave glider. On the other hand, it is confirmed that the wave glider can be detected even at the very low false alarm rate ($10^{-6}$) of the target detection using CFAR. Although the scatter signal by the wave glider could be distinguished from the surrounding ocean clutter in the high resolution SAR image, further research is needed to determine if actual wave gliders are detected in various marine environments.

• Journal of IKEEE
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• v.25 no.3
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• pp.485-492
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• 2021

In this paper, we propose the development of a defect inspection system for polygonal containers. Embedded board consists of main part, communication part, input/output part, etc. The main unit is a main arithmetic unit, and the operating system that drives the embedded board is ported to control input/output for external communication, sensors and control. The input/output unit converts the electrical signals of the sensors installed in the field into digital and transmits them to the main module and plays the role of controlling the external stepper motor. The communication unit performs a role of setting an image capturing camera trigger and driving setting of the control device. The input/output unit converts the electrical signals of the control switches and sensors into digital and transmits them to the main module. In the input circuit for receiving the pulse input related to the operation mode, etc., a photocoupler is designed for each input port in order to minimize the interference of external noise. In order to objectively evaluate the accuracy of the development of the proposed polygonal container defect inspection system, comparison with other machine vision inspection systems is required, but it is impossible because there is currently no machine vision inspection system for polygonal containers. Therefore, by measuring the operation timing with an oscilloscope, it was confirmed that waveforms such as Test Time, One Angle Pulse Value, One Pulse Time, Camera Trigger Pulse, and BLU brightness control were accurately output.