• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.182-188
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• 2006

In this study, we have designed the millimeter-wave passive imaging system which records energy that is reflected or emitted from the source and produces image. The lens and front-end of receiver appeared to be important in the system to detect input thermal noise signal. The lens for signal focusing has been designed by optical transfer function. Amplifier of the imaging systemhas been set up with 40dB in maximum gain, 5 dB in maximum noise figure, and 10GHz in bandwidth to enhance sensitivity for thermal noise and to receive it in wide-band width as well. The SBD MSS-20 141B10D diode has been used for the detector circuit to convert amplified millimeter-wave signals to DC output.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.9
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• pp.1723-1729
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• 2016

Digital watermarking is tried to get an optimum tradeoffs between its performance characteristics, robustness, transparency and capacity. This paper is, therefore, suggesting a watermarking technique that builds multiple barcodes in various frequency bands to implement embedded watermarks that is imperceptible and robust against various attacks. Even though a watermark technique with duplicated barcode watermarks embedded in various frequency bands can satisfy robustness as there is high possibility that watermarks embedded in an image remains after various attacks, the duplicated barcode data can weaken imperceptibility. Thus, to satisfy the conflicting characteristic requirements of watermarks, robustness and imperceptibility, different barcode data is embedded in each frequency band. The test shows that ownership authentication with the technique suggested in this thesis does not require specialized hardware, and extracted watermarks can be easily identified through a mobile barcode scanner app, which allows low complexity, low cost and swift identification.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.63-65
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• 2017

The zodiacal light emission is the thermal emission from the interplanetary dust and the dominant diffuse radiation in the mid- to far-infrared wavelength region. Even in the far-infrared, the contribution of the zodiacal emission is not negligible at the region near the ecliptic plane. The AKARI far-infrared all-sky survey covered 97% of the whole sky in four photometric bands with band central wavelengths of 65, 90, 140, and $160{\mu}m$. AKARI detected the small-scale structure of the zodiacal dust cloud, such as the asteroidal dust bands and the circumsolar ring, in far-infrared wavelength region. Although the most part of the zodiacal light structure in the AKARI far-infrared all-sky image can be well reproduced with the DIRBE zodiacal light model, there are discrepancies in the small-scale structures. In particular, the intensity and the ecliptic latitude of the peak position of the asteroidal dust bands cannot be reproduced precisely with the DIRBE models. The AKARI observational data during more than one year has advantages over the 10-month DIRBE data in modeling the full-sky zodiacal dust cloud. The resulting small-scale zodiacal light structure template has been used to subtract the zodiacal light from the AKARI all-sky maps.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.699-701
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• 2010

Purpose: Mondor's disease is a rare benign condition which involves thrombophlebitis of the superficial veins of the breast and anterior chest wall after breast surgery, breast tissue biopsy, inflammatory reaction, breast cancer, trauma. The affected veins include the lateral thoracic, axillary veins, thoracoepigastric veins and superior epigastric veins. Methods: A 49-year-old woman presented to the outpatient department with complaints of the sudden appearance of a subcutaneous cord just under the skin at left lower lateral abdominal wall 1 month later of bilateral mastectomy due to both severe breast paraffinoma. The cord was initially red and tender and subsequently became a painless, tough, fibrous band that was accompanied by tension and skin retraction. Results: On ultrasonographic findings, palpable threadlike structures at both lateral superficial abdominal wall after bilateral mastectomy were noted. Superficial short elongated hypoechoic tubular structures were noted just under the skin at palpable lower lateral abdominal wall. It was compatible to Mondor's disease of thoracoepigastric vein. Conclusion: The increase in breast surgery will give rise to the increase in the frequency of Mondor's disease clinically. Mondor's disease can be diagnosed with clinical symptoms and image findings and the disease has proved to be benign and self-limited.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.7
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• pp.811-818
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• 2014

This study was aimed to detect Submarine Groundwater Discharge (SGD) distribution image of Sea Surface Temperature (SST) using infrared band of Landsat-7 ETM+ around Jeju island. It is used to analyze SST distribution that DN value of satellite images converted into temperature. The estimation of SGD location is that extracting range of $15{\sim}17^{\circ}C$ from SST. The summer season images(July 28. 2006, Aug. 29. 2006 and Sep. 19. 2008) were used to analyze big difference between SST and temperature of SGD. The results, estimated SGD locations were occurred part of coastal area in northeastern of Jeju island.

• The KIPS Transactions:PartB
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• v.10B no.4
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• pp.465-472
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• 2003

For an effective pre-treatment process of a face input image, it is necessary to detect each of face components, calculate the face area, and estimate the rotary angle of the face. A proposed method of this study can estimate an robust result under such renditions as some different levels of illumination, variable fate sizes, fate rotation angels, and background color similar to skin color of the face. The first step of the proposed method detects the estimated face area that can be calculated by both adapted skin color Information of the band-wide HSV color coordinate converted from RGB coordinate, and skin color Information using histogram. Using the results of the former processes, we can detect a lip area within an estimated face area. After estimating a rotary angle slope of the lip area along the X axis, the method determines the face shape based on face information. After detecting eyes in face area by matching a partial template which is made with both eyes, we can estimate Y axis rotary angle by calculating the eye´s locations in three dimensional space in the reference of the face area. As a result of the experiment on various face images, the effectuality of proposed algorithm was verified.

• Journal of the Korean Institute of Gas
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• v.3 no.2 s.7
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• pp.62-69
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• 1999

This paper presents a design method of dynamic positioning control system(DPS) for floating Platform with rotatable and retractable thrusters using H$\infty$ servo control design method. The norm band of uncertainty is captured by multiplicative perturbation between nominal model and reduced order model. A controller robust to the uncertainty is designed applying H$\infty$ synthesis. The control law satisfying robust stability and nominal performance condition is determined through the mixed sensitivity approach. The control algorithm was evaluated on the basis of computer simulation for a proposed DPS design method and experiments was carried out with an image processing method for measurement of DPS position in a water tank The results of overall experiments show that proposed control method will be good to keep at a specified position. And they are compared with the experimental results by LQG synthesis and H$\infty$ optimal control design method.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.5
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• pp.479-486
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• 2011

In image-based CFD modeling of carotid bifurcation hemodynamics, it is often not possible (or at least not convenient) to impose measured velocity profiles at the common carotid artery inlet. Instead, fully-developed velocity profiles are usually imposed based on measured flow rates. However, some studies reported a pronounced influence of inflow boundary conditions that were based on actual velocity profiles measured by magnetic resonance imaging which showing the unusual presence of a high velocity band in the middle of the vessel during early diastole inconsistent with a Dean-type velocity profile. We demonstrated that those velocity profiles were induced by the presence of modest secondary curvature of the inlet and set about to test whether such more "realistic" velocity profiles might indeed have a more pronounced influence on the carotid bifurcation hemodynamics. We found that inlet boundary condition with axisymmetric fully-developed velocity profile(Womersley flow) is reasonable as long as sufficient CCA inlet length of realistic geometry is applied.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.46-50
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• 2015

The previous studies showed that the visual imagery activated the occipital and posterior inferior temporal area of the brain, and the damage to the occipital cortex impaired the visual mental imagery. We studied current-source distribution of electroencephalography (EEG) to observe neuronal activity during imagery tennis playing. Eleven healthy volunteers were enrolled. All volunteers were right-handed males and novices for tennis playing. The mean age of them was 24.9 years. The EEGs were recorded on the scalp electrodes located according to the International 10~20 System. The number of electrodes was 25 channels including subtemporal electrodes. The EEG recording session was 13 min including 5 segments: resting-I, scenery-slide show, resting-II, watching tennis-game video, and imagery-tennis playing. The recoding durations were 3, 2, 3, 2, and 3 min respectively. Five 'artifact free 3-sec segments' were selected in each segment of 'imagery-tennis playing' and 'resting-II'. We did the frequency domain analysis with the EEG segments using a distributed model of current-source analysis. The statistical-nonparametric maps (SnPMs) were obtained between the segments of 'imagery-tennis playing' and the segments of 'resting-II' (p<0.01). The significant change of current-source density was observed only in alpha-2 frequency band (10~12 Hz). The current-sourcedensity was increased in the hippocampus, parahippocampus, and occipital fusiform gyrus in the right cerebral hemisphere (p<0.01). Imaginary-tennis playing may activate the hippocampal-occipital alpha networks of nondominant hemisphere.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.31.2-31.2
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• 2008

We present the results offar ultraviolet (FUV, 1350-1750 ${\AA}$) auroral observations made by the Far-ultraviolet IMaging Spectrograph (FIMS) instrument on the Korean microsatellite STSAT-1. The instrument was capable of resolving spatial structures of a few kilometers with the spectral resolution of 2-3 ${\AA}$. The observations were carried out simultaneously with the measurement of precipitating electrons using an electrostatic analyzer (ESA, 100 eV-20 keV) and a solid state telescope (SST, 170 keV-360 keV) on board the same satellite. With a careful mapping of the field lines, we were able to correlate the particle spectrum to the corresponding FUV spectrum of the footprints of the FIMS image that varied significantly in fine scales. We divided the FIMS spectral band into the LBH long (LBHL, 1640-1715 ${\AA}$) and LBH short (LBHS, 1380-1455 ${\AA}$) bands, and compared the electron energies with the intensities of LBHL and LBHS for the well-defined inverted-V structures. The result shows a strong correlation between the total LBH intensity and the energy flux measured by ESAwhile the peak energy itself does not correlate well with the LBH intensity. On the other hand, it was observed that the ratio of the LBHL intensity to that of LBHS increased significantly as the peak electron energy increased, primarily due to a smaller absorption by O2 at LBHL than at LBHS.