• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.1246-1251
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• 2006

본 연구에서는 영역 분할 알고리즘과 3차 스플라인 보간법을 이용하여 스테인드 글라스 렌더링을 위한 개선된 유리 타일 생성 알고리즘을 제안하였다. 먼저 유리 타일의 초기 형태를 추출하기 위하여 입력 영상에 Mean shift 분할 알고리즘을 적용하였다. Mean shift 분할 알고리즘은 영상의 각 픽셀(pixel)에서의 지역 밀도 최대 점(local density maximum)을 찾아 클러스터링(clustering)하는 알고리즘으로 영상을 효과적으로 분할할 수 있다. 그리고 분할된 영역에서 영역을 사용자 입력으로 병합하고, 영역에서 부적절한 형태를 없애기 위해 본 연구에서는 형태론적 연산(morphological operation)을 이용하였다. 추출된 영역으로부터 유리 타일의 형태로 만들기 위하여 추출된 각각의 영역에 3차 스플라인 보간법(cubic spline interpolation)을 적용하여 경계가 완화된 영역과 납틀(leading)의 형태를 얻는다. 그 다음 영역을 스플라인 곡선(spline curve)을 이용하여 재분할하고, 각 영역에 변환(transformation)된 색상을 적용하여 최종적인 유리 타일을 만들어낸다. 본 연구에서는 3차 스플라인 보간법을 이용하여 실제 스테인드 글라스에서 생길 수 있는 부드러운 경계를 갖는 유리 타일의 형태를 만들어 이를 스테인드 글라스 렌더링에 이용하였다. 이 방법은 기존의 영역 분할 알고리즘에 형태론적 연산만을 적용하여 유리 타일의 형태를 생성하는 것보다 효과적으로 유리 타일의 형태를 생성할 수 있다. 또한, 생성된 영역에 재분할 과정을 거쳐서 작은 유리 타일이 모여서 이루는 조형적인 형태를 이룰 수 있도록 하였다.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.12 no.2
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• pp.121-125
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• 2001

Singing requires exquisite coordination between the respiratory and phonatory system to efficiently control glottal airflow. Respiratory function and vocal aerodynamics were investigated in six female professional sopranos and in six female subjects without vocal training. All sopranos had more than 15 years of formal classic vocal training. Pulmonary function test data on simple pulmonary function, flow volume curve, static lung volumes, maximum inspiratory pressure(MIP), and maximum expiratory pressure(MEP) were obtained from all subjects. Vocal aerodynamic studies of maximum phonation time(MPT), phonation quotient, and mean glottal flow rates (MFR) were also measured in all subjects. Simple pulmonary function in professional sopranos was generally the same as that of other female subjects without vocal training. However, MIP and MEP showing respiratory muscle forces were significantly elevated in professional sopranos, compared to those of other female subjects without vocal training. Maximum phonation times and phonation quotient in sopranos are longer than those of other female subjects even though there were no differences in simple pulmonary function. High-pitched tones were made with significantly higher mean glottal flow rates(GFR) in normal subjects than low-pitched tones, whereas no changes in GFR were found in sopranos. The result indicated that sopranos demonstrated significant improvements in aerodynamic measures of GFR, maximum phonation time, suggesting an increase in glottal efficiency.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.215-219
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• 2005

A macro spreadsheet model, WEANES (Wet Pond Annual Efficiency Simulation Model), has been developed to predict the long-term or annual removal efficiencies of wet retention/detention basins. The model uses historical, site-specific, multi-year, rainfall data, usually available from a nearby National Oceanic and Atmospheric Administration (NOAA) climatological station to estimate basin efficiencies which are calculated based on annual mass loads. Other required input parameters are: 1) watershed parameters; drainage area, pervious curve number, directly connected impervious area, and ti me of concentration, 2) pond parameters; control and overflow elevations, pond side slopes, surface areas at control elevation and pond bottom; 3) outlet structure parameters; 4) pollutant event mean concentrations; and 5) pond loss rate which is defined as the net loss due to evaporation, infiltration and water reuse. The model offers default options for parameters such as pollutant event mean concentrations and pond loss rate. The model can serve as a design, planning, and permitting tool for consulting engineers, planners and government regulators.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.4
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• pp.311-325
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• 2009

This paper presents a method for analyzing Hangul glyphs with their outline fonts and obtaining intermediate fonts with two different fonts. The glyphs are represented and analyzed hierarchically such as characters, components(letters) and strokes. With the analysis results, we obtain several intermediate glyphs by morphing two different glyphs of same character. For a natural glyph contour morphing, we employ the curve morphing algorithm by weighted mean of strings. In addition, we provide four operations for transformation of glyphs with different topology. As a result, it is illustrated that the proposed Hangul glyphs morphing scheme is useful for new font generation from any exist fonts or handwritings.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.6
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• pp.11-20
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• 2007

In order to make the way to determine the instream flow more practically, we have investigated many case studies and reviewed reports and papers. To validate instream flow level suggested by the case studies, DAWAST and HEC-RAS model were applied to the Gap-stream watershed in Daejeon city. Flow-duration analysis was performed both with the stream flow data gauged in the Indong, Boksu, and Hoeduck stations, and with the stream flow data estimated by the DAWAST model and the specific discharge method. Instream flow was determined among the flow-duration analysis, DAWAST, HEC-RAS model and mass balance approach. It was satisfied with various factors such as target water quality, water depth for eco-system and resorts, water surface width, flow velocity for landscape in dry season. The study suggested that the mean low flow could be replaced into the instream flow for the preliminary study because the instream flow considering ecosystem, landscape, water-friendly environment and water quality was generally close to the mean low flow.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.3
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• pp.34-44
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• 1986

Particle size distribution of airborne suspended particulate concentrations according to particle size in the events of yellow sand phenomena, have been measured and analyzed by using Andersen air sampler for four years, January 1982 through December 1985. The conclusions are as follows: 1. Yellow sand phenomena, generally, occur between March and May. 2. The frequent occurrences of yellow sand were observed during March and April and airborne suspended particulate concentrations in the cases of yellow sand appeared to be 2 $\sim$ 3.4 times higher than those of normal conditions. 3. Geometric mean particle diameter and its geometric mean standard deviation by logarithmic normal distribution sheet, were quite close to each other and log-distribution curves showed similar shapes. 4. Analysis by particle size distribution curve showed bi-modal distribution. 5. Concentrations of coarse particles in normal conditions were 1.2 $\sim$ 2 times higher than those of fine particles and, similarly, coarse particle concentrations in yellow sand cases were 1.3 $\sim$ 2.5 times higher than those of fine particles. 6. Concentrations of coarse particles in yellow sand cases were 2 $\sim$ 3.6 times higher than those in normal conditions and those of fine particles were 1.7 $\sim$ 3.5 times higher.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1107-1117
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• 1990

The regulatory role of the post \ulcorner1-and \ulcorner2-adrenoceptors on cardiac function, particularly in coronary flow rate, was investigated in the isolated rat heart treated with 10-6 M propranolol. When introduced into the left atrium of the heart, phenylephrine[10-7-10-2 M] decreased coronary flow rate and increased mean coronary resistance in a dose related fashion, but did not affect heart rate. Methoxamine also elicited the increment of coronary resistance and the decrement of coronary flow rate, though the effects of methoxamine were weaker than those by phenylephrine. The effect of phenylephrine was inhibited by 1\ulcornerM prazosin and shifting the dose-response curve to the right. The effects of clonidine, a selective \ulcorner2-adrenoceptor agonist, were studied in the heart taken from reserpinized rats. Clonidine increased coronary resistance, decreased heart rate and coronary flow rate with a dose-dependent manner. These effects were abolished by 10-6 M yohimbine, a selective \ulcorner2-antagonist, and were not affected by 10-6M prazosin. Clonidine also decreased coronary flow and increased mean coronary resistance in electric paced heart. These effects were inhibited by rawoulscine, a selective ca-antagonist. These results indicate that the stimulation of both post \ulcorner1-and \ulcorner2-adrenoceptor causes coronary vasoconstiction. And it is inferred that this model of sympathomimetics-induced coronary vasospasm may provide a useful tool for investigating spasmolytic agents which are of benefit in the treatment of variant angina.

• Publications of The Korean Astronomical Society
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• v.18 no.1
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• pp.75-79
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• 2003

The characteristics of the BOES (Bohyunsan Observatory Echelle Spectrograph) CCD camera is presented. In order to get optimum gain and readout noise of the CCD, we examine the variation of the gain and readout noise by changing the value of output drain voltage of the CCD and measuring the gain using transfer curve, which is defined as the plot of variance versus mean exposure level of a homogeneous light onto the CCD surface. The gain and readout noises are optimised to be 0.5e$^-$/ADU and 3e$^-$, which is good for highest signal-to-noise ratio and contrast for the low light level characteristics of the BOES. We also measure the dark count of the CCD by getting five dark images with 3600 seconds exposure time. The mean dark count from median stacked dark images is essentially zero. A table of positions of defected pixels is also presented.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.8 s.251
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• pp.897-905
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• 2006

This study considers an experimental design of disturbance compensation control to improve stabilization performance of main battle tanks. An adaptive non-parametric design technique based on the Filtered-x Least Mean Square(FXLMS) algorithm is applied in the consideration of model uncertainties. The optimal compensator is designed by two-step design procedures: determination of frequency response function of the disturbance compensator which can cancel the disturbance of series of single harmonics by using the FXLMS algorithm and determination of the compensator polynomial which can fit the frequency response function obtained in the first step optimally by using a curve fitting technique. The disturbance compensator is applied to a simple experimental gun-torsion bar-motor system which simulates gun driving servo-system. Along with experimental results, the feasibility of the proposed technique is illustrated. Experimental results demonstrate that the proposed control reduces the standard deviation of stabilization error to 47.6% that by feedback control alone. The directional properties of the FXLMS Algorithm such as the direction of convergence and its convergence speed are also verified experimentally.

• The Korean Journal of Nuclear Medicine
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• v.3 no.2
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• pp.23-27
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• 1969

Plasma glucose levels before and after oral glucose administration have been compared in a group of 76 thyrotoxic subjects and a group of 8 normal control subjects in order to study the effect of glucose loading in thyrotoxicosis. Following were the results: 1. The mean fasting plasma glucose level was elevated in the thyrotoxic group(95.5mg%) compared to normal control group (88mg%). 2. The peak of glucose tolerance curve is at 30 minutes after glucose administration in both groups, but its mean value was 44mg% higher in thyrotoxic group than in control group. 3. The plasma glucose levels returned towards the fasting level in the later stage of the test more rapidly in thyrotoxic group than in control group. 4. 69.6% of oral glucose tolerance tests were impaired in the thyrotoxic group, and the occurance of abnormal glucose tolerance could be related to the degree of thyrotoxicity, sex and age. 5. The mechanisms of the impaired glucose tolerance in thyrotoxicosis are thought to be related to an increased rate of glucose absorption from gastrointestinal tract, abnormal liver function with decreased hepatic glycogenesis, increased glucose oxidation, decreased pancreatic release of insulin, and genetic relationship between diabetes and thyrotoxicosis.