• Toxicological Research
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• v.22 no.4
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• pp.417-422
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• 2006

Cytogenetic and hematological analysis was performed in peripheral blood obtained from cattle bred in the high background radiation areas (HBRA, Goesan-gun, Cheongwon-gun, Boeun-gun) and a control area. The frequencies of gamma-ray induced micronuclei (MN) in the cytokinesis-blocked (CB) lymphocytes at several doses were measured in 3 cattle. An estimated dose of radiation was calculated by a best fitting linear-quadratic model based on the radiation-induced MN formation from the bovine lymphocytes exposed in vitro to radiation over the range from 0 mGy to 1,969 mGy. The measurements performed after irradiation showed dose-related increases in the MN frequency in each donors. The results were analyzed using a linear-quadratic model with a line of best fit of $y=(0.0583{\pm}0.0137)D+(0.0366{\pm}0.0081)D^2+(0.0093{\pm}0.0015)$ (y=number of MN/CB cells and D=irradiation dose in Gy). MN rates per 1,000 CB lymphocytes of cattle from the Goesan-gun, Cheongwon-gun, Boeun-gun and the control area were $6.50{\pm}2.72,\;9.00{\pm}4.50,\;10.89{\pm}4.23\;and\;9.60{\pm}4.70$, respectively. The MN frequencies of CB lymphocytes from cattle bred in 4 areas mean that the values are within the background variation in this experiment. The MN frequencies and hematological values were similar regardless of whether the cattle were bred in the HBRA or the control area.

• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.101-110
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• 2015

Synthetic Aperture Radar Interferometry (InSAR) is affected by various noise source such as atmospheric artifact, orbital error, processing noise etc.. Especially, one of the dominant noise source for long-wave SAR system, such as ALOS PALSAR (L-band SAR satellite) is the ionosphere effect because phase delays on radar pulse through the ionosphere are proportional to the radar wavelength. To avoid misinterpret of phase signal in the interferogram, it is necessary to detect and correct ionospheric errors. Recently, a MAI (Multipler Aperture SAR Interferometry) based ionospheric correction method has been proposed and considered one of the effective method to reduce phase errors by ionospheric effect. In this paper, we introduce the MAI-based method for ionospheric correction. Moreover we propose an efficient method that apply the method over non-coherent area using directional filter. Finally, we apply the proposed method to the ALOS PALSAR pairs, which include the west sea coast region in Korea. A polynomial fitting method, which is frequently adopted in InSAR processing, has been applied for the mitigation of phase distortion by the orbital error. However, the interferogram still has low frequency of Sin pattern along the azimuth direction. In contrast, after we applied the proposed method for ionospheric correction, the low frequency pattern is mitigated and the profile results has stable phase variation values within ${\pm}1rad$. Our results show that this method provides a promising way to correct orbital and ionospheric artifact and would be important technique to improve the accuracy and the availability for L-band or P-band systems.

• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.469-475
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• 2005

Cytogenetic and hematological analysis was performed in peripheral blood obtained from pigs bred in the high background radiation areas (HBRA) (Cheongwon-gun and Boeun-gun) and a control area. The frequencies of gamma-ray induced micronuclei (MN) in the cytokinesis-blocked (CB) lymphocytes at several doses were measured in three pigs. An estimated dose of radiation was calculated by a best fitting linear-quadratic model based on the radiation-induced MN formation from the swine lymphocytes exposed in vitro to radiation over the range from 0 mGy to 1,969 mGy. The measurements performed after irradiation showed dose-related increases in the MN frequency in each donors. The results were analyzed using a linear-quadratic model with a line of best fit of $y=0.0005404D^2+0.04237D+0.00833$ [y = number of MN/cytokinesis-blocked (CB) cells and D = irradiation dose in Gy]. MN rates per 1,000 CB lymphocytes of pig from the HBRA (Cheongwon-gun, Boeun-gun) and the control area were $6.70{\pm}2.36$, $9.00{\pm}3.50$ and $11.00{\pm}2.98$, respectively. The MN frequencies of CB lymphocytes from pigs bred in three areas means that the values are within the background variation in this experiment. The MN frequencies and hematological values were similar regardless of whether the pigs were bred in the HBRA or the control area.

• Journal of Internet Computing and Services
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• v.20 no.6
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• pp.143-156
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• 2019

Discussion on OTT regulation has become fiercer, as OTT services' impacts on the global and domestic media market have been exponentially growing. In South Korea, it is argued that, on the basis of the similarity between television program and OTT's video content, OTT needs to be regulated in order to protect fair competition and to control sociocultural effects. In many of the discussions, developed countries' cases have been used for supporting OTT regulation. In this paper, we first analyzed the global OTT market trends based on our own categorization of OTT services. then we assessed the validity of the application of the foreign cases in the current OTT regulation debates in Korea. We proposed six OTT types (aggregation, mediation, mediation-aggregation, multi-screen, outlet, and outlet-linear) simultaneously considering service operator' origin, business model, content format, and content delivery. These services have been consistently evolving, and the OTT market has been increasingly competitive especially around content differentiation. Regulators must be wary of hastily introducing competition regulation to the dynamically innovating OTT market. The foreign cases, including the US, EU, the UK, and Japan, hardly seem to be appropriate bases for strengthening OTT regulation. Rather, they were focused more on promoting competition in the domestic media market and enriching the content ecosystem. Therefore, we need to consider revision of the outdated media regulation frameworks instead of fitting OTT under them, and to recognize the priority of securing practical jurisdiction on global service providers before capturing local players into the conventional regulation systems.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.6
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• pp.398-403
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• 2012

Purpose: Mandible resection and discontinuity defect created lead to aesthetic and functional problems. The iliac crest bone graft exhibits relative ease for bone harvesting, possibility of two team approach, ability to close the wound primarily, large amount of corticocancellous bone and relatively few complications. Whereas the use of free vascularized flaps has donor site morbidity and worse-fitting bone contour, the use of nonvascularized iliac bone graft has advantages in the operation time and patients' recovery time. So, nonvascularized iliac bone graft could be an attractive option. Methods: Twenty-one patients (M:F=1:1.1) underwent iliac crest bone harvesting for reconstruction of mandibular discontinuity defect (mean length : $61.6{\pm}17.8$ mm), from May 2005 to October 2011 at the Department of Oral and Maxillofacial Surgery in Kyungpook National University. The average age was $44.1{\pm}16.4$ years and the mean follow up periods was $28.2{\pm}22.7$ months. Bone resorption rate, according to age, sex, primary lesion, location and distance of defect, type of fixation plate, time of graft and pre-operative radiation therapy, were measured in each patient. Results: The mean bone resorption rate was $16.1{\pm}9.0%$. Bone resorption rate was significantly increased in mandibular defect that is over 6 cm in size (P=0.015, P<0.05) and the cases treated pre-operative radiation therapy (P=0.017, P<0.05). All was successfully fixed and maintained for the long-term follow-up. There were a few donor site complications and almost all patients were shown favorable outcome without severe bone resorption in this study. Conclusion: The nonvascularized iliac bone graft seems to be a reasonably reliable treatment option for reconstruction of mandibular discontinuity defects.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.79.2-79.2
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• 2012

SN 2011fe (also known as PTF 11kly) is a Type-1a supernova that appeared in M101, 2011 August. Being only 6.4 Mpc away, this supernova has been intensively observed by various facilities in the world. We monitored this supernova in UBVRI, grizY, and ZYJHK-bands using SNUO, LOAO, SOAO, CQUEAN/McDonald, UKIRT telescopes, and small telescopes in Korea and Mongolia. The monitoring observation is still ongoing, and the light curve has been accumulated over a year. We present the results of the long-term monitoring observation, together with a light-curve fitting result. We will also discuss our findings in terms of the usefulness of Type-Ia supernovae as a distance indicator.

• Korean Journal of Veterinary Research
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• v.42 no.1
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• pp.1-6
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• 2002

The frequencies of gamma-ray-induced micronuclei (MN) in cytokinesis-blocked (CB) lymphocytes at several doses were measured in three donors of three species (human, rabbit, dog). Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. When analysed by linear-quadratic model the line of best fit was : human : $y=0.1184D+0.01867D^2+0.01$, rabbit : $y=0.0387D+0.00528D^2+0.01$ (y = number of MN/CB cells and D = irradiation dose in Gy). The relative sensitivity of rabbit lymphocytes compared with human lymphocytes was estimated by best fitting linear-quadratic model based on the radiation-induced MN data over the range from 0 Gy to 4 Gy. In the case of MN frequency with 0.2, the relative sensitivities of rabbit lymphocytes was 0.39. These data indicate that the induction of MN in rabbit CB cells following irradiation was much less sensitive to the MN induction effects of gamma-irradiation than those from human. The MN assay with dog lymphocytes was very difficult and time-consumed because the dog PHA-stimulated lymphocytes yielded cultures with very low level of CB cells formation in the condition of this experiment. Our in vitro radiobiological study confirmed that the cytogenetic response obtained in blood from rabbit can be utilized for application in environmental studies.

• Journal of the Mineralogical Society of Korea
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• v.20 no.4
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• pp.367-376
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• 2007

Aenigmatite, $Na_4(Fe^{2+},Ti,Fe^{3+}){_{12}}(Fe^{3+},Si){_{12}}O_{40}$, is a common constituent of sodium-rich alkaline igneous rocks and is classified a an open-branched single-chain silicate. $M\ddot{o}ssbauer$ spectroscopy of three natural aenigmatite specimens were done and the detailed crystal chemistry was obtained. Fitting of $M\ddot{o}ssbauer$ spectra led to the resolution of nine peaks. They consist of three doublets of $Fe^{2+}/oct$ and one merged peak at low velocity matching to two small peaks at high velocity which were assigned to $Fe^{3+}/tet\;and\;Fe^{2+}/oct$, respectively. Using the peak area for $Fe^{2+}\;and\;Fe^{3+}$ peaks, analytical data were recalculated. Precise assignment of $Fe^{2+}\;and\;Fe^{3+}$ ions in tetrahderal and octahedral sites revealed detailed crystal chemistry of aenigmatite. The existence of significant amounts of $Fe^{3+}/tet$ indicates that $Fe^{3+}$ has preference over $Al^{3+}$ for the tetrahedral sites. Crystal chemistry of aenigmatite (AEN1) yields the formula of $(Na_{3.97}Ca_{0.03})(Ca_{0.11}Mn_{0.59}Fe^{2+}{_{8.07}}Ti_{2.07}Mg_{0.70}Fe^{3+}{_{0.43}}Al_{0.04})(Fe^{3+}{_{0.56}}Al_{0.18}Si_{11.26})O_{40}$.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.10
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• pp.713-722
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• 2013

This paper proposes a method of using depth information to detect the hand region in real-time based on the cascade method. In order to ensure stable and speedy detection of the hand region even under conditions of lighting changes in the test environment, this study uses only features based on depth information, and proposes a method of detecting the hand region by means of a classifier that uses boosting and cascading methods. First, in order to extract features using only depth information, we calculate the difference between the depth value at the center of the input image and the average of depth value within the segmented block, and to ensure that hand regions of all sizes will be detected, we use the central depth value and the second order linear model to predict the size of the hand region. The cascade method is applied to implement training and recognition by extracting features from the hand region. The classifier proposed in this paper maintains accuracy and enhances speed by composing each stage into a single weak classifier and obtaining the threshold value that satisfies the detection rate while exhibiting the lowest error rate to perform over-fitting training. The trained classifier is used to classify the hand region, and detects the final hand region in the final merger stage. Lastly, to verify performance, we perform quantitative and qualitative comparative analyses with various conventional AdaBoost algorithms to confirm the efficiency of the hand region detection algorithm proposed in this paper.

• Geophysics and Geophysical Exploration
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• v.23 no.1
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• pp.38-49
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• 2020

Full-waveform inversion (FWI) is an optimization process of fitting observed and modeled data to reconstruct high-resolution subsurface physical models. In acoustic FWI (AFWI), pressure data acquired using a marine streamer has mainly been used to reconstruct the subsurface P-wave velocity models. With recent advances in marine seismic-acquisition techniques, acquiring multi-component data in marine environments have become increasingly common. Thus, AFWI strategies must be developed to effectively use marine multi-component data. Herein, we proposed an AFWI strategy using horizontal and vertical particle-acceleration data. By analyzing the modeled acoustic data and conducting sensitivity kernel analysis, we first investigated the characteristics of each data component using AFWI. Common-shot gathers show that direct, diving, and reflection waves appearing in the pressure data are separated in each component of the particle-acceleration data. Sensitivity kernel analyses show that the horizontal particle-acceleration wavefields typically contribute to the recovery of the long-wavelength structures in the shallow part of the model, and the vertical particle-acceleration wavefields are generally required to reconstruct long- and short-wavelength structures in the deep parts and over the whole area of a given model. Finally, we present a sequential-inversion strategy for using the particle-acceleration wavefields. We believe that this approach can be used to reconstruct a reasonable P-wave velocity model, even when the pressure data is not available.