• Journal of Broadcast Engineering
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• v.17 no.4
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• pp.640-658
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• 2012

One of the existing terrestrial multi-channel DTV service frameworks, called KoreaView, provides four programs, composed of MPEG-2 based one HD video and H.264/AVC based three SD videos within one single 6MHz frequency bandwidth. However the additional 3 SD videos can not provide enough quality due to its reduced spatial resolution and low target bitrates. In this paper, we propose a framework, which is called a terrestrial multi-channel high quality hybrid DTV service, to overcome such a weakness of KoreaView services. In the proposed framework, the three additional SD videos are encoded based on an H.264/SVC Spatial Base layer, which is compliant with H.264/AVC, and are delivered via broadcasting networks. On the other hand, and the corresponding three additional HD videos are encoded based on an H.264/SVC Spatial Enhancement layer, which are transmitted over broadband networks such as Internet, thus allowing the three additional videos for users with better quality of experience. In order to verify the effectiveness of the proposed framework, various experimental results are provided for real video contents being used for DTV services. First, the experimental results show that, when the SD sequences are encoded by the H.264/SVC Spatial Base layer at a target bitrate of 1.5Mbps, the resulting PSNR values are ranged from 34.5dB to 42.9dB, which is a sufficient level of service quality. Also it is noted that 690kbps-8,200kbps are needed for the HD test sequences when they are encoded in the H.264/SVC Spatial Enhancement layer at similar PSNR values for the same HD sequences encoded by MPEG-2 at a target bitrate of 12 Mbps.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.400-405
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• 2014

G-protein coupled receptor 119 (GPR119) has emerged as a novel target for the treatment of type 2 diabetes mellitus. GPR119 is involved in glucose-stimulated insulin secretion (GSIS) from the pancreatic b-cells and intestinal cells. In this study, we identified a novel small-molecule GPR119 agonist, HD047703, which raises intracellular cAMP concentrations in pancreatic ${\beta}$-cells and can be expected to potentiate glucose-stimulated insulin secretion from human GPR119 receptor stably expressing cells (CHO cells). We evaluated the acute efficacy of HD047703 by the oral glucose tolerance test (OGTT) in normal C57BL/6J mice. Then, chronic administrations of HD047703 were performed to determine its efficacy in various diabetic rodent models. Single administration of HD047703 caused improved glycemic control during OGTT in a dose-dependent manner in normal mice, and the plasma GLP-1 level was also increased. With respect to chronic efficacy, we observed a decline in blood glucose levels in db/db, ob/ob and DIO mice. These results suggest that HD047703 may be a potentially promising anti-diabetic agent.

• Advances in pediatric surgery
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• v.19 no.2
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• pp.122-129
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• 2013

Immature ganglion cell (IGC) is known for its relationship with intestinal motility and its impact on postoperative functional outcomes of Hirschsprung's disease (HD). There are few studies on the relationship between intestinal dysmotility and IGC in HD patients. 67 patients pathologically diagnosed with HD and who received definitive operation in Seoul National University Children's Hospital from 2010 to 2011 were included. 10 patients were excluded due to inadequate immunohistochemical staining results. The proximal end of resected ganglionic segment was evaluated with immunohistochemistry examination with MAP-2, a marker of ganglionic cells and bcl-2, a marker of IGCs The median age at operation was 155 (15-4678) day-old. 55 (96.5%) patients positive for bcl-2, were regarded as having IGC, and 2 (3.5%) patients positive for MAP-2 but negative for bcl-2, were regarded as having only mature ganglion cells. In the bcl-2 positive group, there were 7 patients (12.7%) with constipation, 15 patients (27.3%) with soiling, 3 patients (5.5%) with perianal excoriation and 6 patients (10.9%) with medication use. In bcl-2 negative group, intestinal dysmotility was not seen. There was no statistical significance in the two groups. Considering that HD is diagnosed at a young age, the rate of IGC present is very high and it might be inappropriate to relate IGC to functional outcome at young ages.

• Journal of Life Science
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• v.23 no.8
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• pp.1025-1031
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• 2013

From a 95% ethanolic extract of H. diffusa, four marker compounds (HD1~HD4) were isolated, which were relatively unique and exist in comparably high contents. The structures of marker compounds were identified as digitolutein (1), 2-hydroxy-3-methylanthraquinone (2), (E/Z)-6-O-p-coumaroyl scandoside methyl ester (4:1 mixture) (3), and (E/Z)-6-O-p-methoxycinnamoyl scandoside methyl ester (4:1 mixture) (4), respectively, on the basis of $^{13}C$ and $^1H$-NMR analyses. The calibration curves of marker compounds showed high linearity, as their correlation coefficient ($R^2$) were in the range of 0.9991~0.9999. In addition, the limit of detection (LOD) and the limit of quantification (LOQ) were $0.03{\sim}0.07{\mu}g/ml$ and $0.099{\sim}0.231{\mu}g/ml$, respectively. The intra-day/inter-day precision and accuracy were 0.23~2.00%/0.25~1.16% and 94.60~108.44%/94.73-110.23%, respectively. The optimal HPLC conditions for the simultaneous quantification of HD1~HD4 were as follows: stationary phase; Merck Chromolith RP-18e ($100{\times}4.6mm$, $5{\mu}m$), column temp.; room temperature, UV detection at 280 nm, flow rate; 2.0 ml/min, injection volume; $10{\mu}l$, mobile phase; start with the mixture of 80% solvent A ($H_2O$ containing 0.5% acetic acid) and 20% solvent B (methanol containing 0.5% acetic acid) and gradually decrease solvent A to 40% in 9 min., then retain this condition to 18 min. Under the HPLC condition, the four marker compounds 1~4 were successfully separated without any interference of other constituents. The results obtained in this study are expected to be helpful for the development of nutraceutics and natural medicines and for the quality control of this plant.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.553-560
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• 2020

This paper presents an algorithm for identifying and eliminating errors by seagrasses in coastal bathymetry surveying using drone and HD camera. Survey errors due to seagrasses were identified, segmentated and eliminated using a L∗a∗b color space model. Bathymetry survey using a drone and HD camera has many advantages over conventional survey methods such as ship-board acoustic sounder or manual level survey which are time consuming and expensive. However, errors caused by sea bed reflectance due to seagrasses habitat hamper the development of new surveying tool. Seagrasses are the flowering plants which start to grow in November and flourish to maximum density until April in Korea. We developed a new algorithm for identifying seagrasses habitat locations and eliminating errors due to seagrasses to get the accurate depth survey data. We tested our algorithm at Wolpo beach. Bathymetry survey data which were obtained using a drone with HD camera and calibrated to eliminate errors due to seagrasses, were compared with depth survey data obtained using ship-board multi-beam acoustic sounder. The abnormal bathymetry data which are defined as the excess of 1.5 times of a standard deviation of random errors, are composed of 8.6% of the test site of area of 200 m by 300 m. By applying the developed algorithm, 92% of abnnormal bathymetry data were successfully eliminated and 33% of RMS errors were reduced.

• Communications for Statistical Applications and Methods
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• v.5 no.2
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• pp.517-529
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• 1998

When the sample size is small the robust minimum Hellinger distance (HD) estimator can have substantially poor relative efficiency at the true model. Similarly, approximating the exact null distributions of the ordinary Hellinger distance tests with the limiting chi-square distributions can be quite inappropriate in small samples. To overcome these problems Harris and Basu (1994) and Basu et at. (1996) recommended using a modified HD called penalized Hellinger distance (PHD). Lindsay (1994) and Basu et al. (1997) showed that another density based distance, namely the negative exponential disparity (NED), is a major competitor to the Hellinger distance in producing an asymptotically fully efficient and robust estimator. In this paper we investigate the small sample performance of the estimates and tests based on the NED and penalized NED (PNED). Our results indicate that, in the settings considered here, the NED, unlike the HD, produces estimators that perform very well in small samples and penalizing the NED does not help. However, in testing of hypotheses, the deviance test based on a PNED appears to achieve the best small-sample level compared to tests based on the NED, HD and PHD.

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.1
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• pp.17-21
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• 2005

Purfose: This study was to observe the phosphamidon reduction rate after haemoperfusion (HP) and Hemodialysis (HD) in vitro. Methods: We started off by measuring the clearance of HD and HP for the phosphamidon in vitro. Phosphamidon was measured hourly by High-pressure liquid chromatography. Results: Phosphamidon clearance was effectiveness in HP and HD. Phosphamidon reduction rate was no difference between HD and HP; $64\%$ versus $91.\%1$ at starting, $82.2\%$ versus $80.2\%$ at 1 hours, $82.2\%$ versus $73.8\%$ at 2 hours, $34.4\%$ versus $14.0\%$ at 3 hours, $14.1\%$ versus $27.4\%$ at 4 hours, $0\%$ versus $3.3\%$ at 5 hours. Conculsion: Extracorporeal elimination of phosphamidon is effective by hemoperfusio and hemodialysis in vitro. We suggest hemoperfusion may be effective in organophsphate intoxication patients.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.140.2-140.2
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• 2011

We present high-resolution radial velocity (RV) measurements of K2 giant HD 66141 from December 2003 to January 2011 using the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) at Bohyunsan Optical Astronomy Observatory (BOAO). We find that the RV measurements for HD 66141 exhibit a periodic variation of 480 days with a semi-amplitude of 146 m/s. We do not find the correlation between RV variations and a chromospheric activity indicator (H line). The Hipparcos photometry as well as bisector velocity span (BVS) also do not show any obvious correlations with RV variations. Thus, Keplerian motion is the most likely explanation, which suggests that the RV variations arise from an orbital motion. Assuming a possible stellar mass of 1.5 $M{\odot}$, for HD 66141, we obtain a minimum mass for the planetary companion of 7.4 MJup with an orbital semi-major axis of 1.4 AU, and an eccentricity of 0.07. We support that planet occurrence rate around evolved stars is more than 10 % (Dollinger et al. 2009) as well as more massive stars do form significantly more massive planetary companions (Johnson et al. 2007; Lovis & Mayor 2007; Dollinger et al. 2009).

• Journal of the Semiconductor & Display Technology
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• v.8 no.2
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• pp.59-62
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• 2009

In order to check the validation of LC simulation, 0.7 inch LCOS panel in full-HD resolution was fabricated and used for the electro-optical measurement. Compared the measured data with the calculated data, the averaged difference was 1.72% under 0 ~ +6 V bias on pixel electrode. To improve the optical characteristics of full-HD LCOS panel, the planar structure and trench structures (0.1 um, 0.2 um and 0.3 um-in-depth) between adjacent pixels were investigated with LC simulation. The planar structure showed the higher reflectance and faster reflectance-voltage response time than the trench structure. The optical fill factor and contrast ratio of planar structure were also higher than those of trench structures. As compared 1 um-in-depth trench structure resembled to the real structure with the planar structure, the optical fill factor was improved by 1.15% and the contrast ratio was improved by 5.26%. In order to minimize the loss of luminance and contrast ratio, the planar structure need to be applied between adjacent pixels.

• Radiation Oncology Journal
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• v.38 no.1
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• pp.35-43
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• 2020

Purpose: This retrospective study compares higher-dose whole-brain radiotherapy (hdWBRT) with reduced-dose WBRT (rdWBRT) in terms of clinical efficacy and toxicity profile in patients treated for primary central nervous system lymphoma (PCNSL). Materials and Methods: Radiotherapy followed by high-dose methotrexate (HD-MTX)-based chemotherapy was administered to immunocompetent patients with histologically confirmed PCNSL between 2000 and 2016. Response to chemotherapy was taken into account when prescribing the radiation dose to the whole brain and primary tumor bed. The whole brain dose was ≤23.4 Gy for rdWBRT (n = 20) and >23.4 Gy for hdWBRT (n = 68). Patients manifesting cognitive disturbance, memory impairment and dysarthria were considered to have neurotoxicity. A median follow-up was 3.62 years. Results: The 3-year overall survival (OS) and progression-free survival (PFS) were 70.0% and 48.9% with rdWBRT, and 63.2% and 43.2% with hdWBRT. The 3-year OS and PFS among patients with partial response (n = 45) after chemotherapy were 77.8% and 53.3% with rdWBRT, and 58.3% and 45.8% with hdWBRT (p > 0.05). Among patients with complete response achieved during follow-up, the 3-year freedom from neurotoxicity (FFNT) rate was 94.1% with rdWBRT and 62.4% with hdWBRT. Among patients aged ≥60 years, the 3-year FFNT rate was 87.5% with rdWBRT and 39.1% with hdWBRT (p = 0.49). Neurotoxicity was not observed after rdWBRT in patients aged below 60 years. Conclusion: rdWBRT with tumor bed boost combined with upfront HD-MTX is less neurotoxic and results in effective survival as higher-dose radiotherapy even in partial response after chemotherapy.