• 대한전자공학회논문지SP
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• 제37권2호
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• pp.50-59
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• 2000

본 논문에서는 분수계 기반 영상 분할의 속도 개선을 위한 새로운 전처리 방법을 제안하였다 영상 분할을 위한 분수계 변환에 있어서, 단순히 단일척도 또는 다중척도의 형태학적 기울기 연산자를 사용하여 만드는 기존의 기준 영상과는 달리, 제안한 방법에서는 원 영상에 라플라시안 연산을 수행해 램프 에지의 위치와 에지 폭을 구한후 이로부터 램프 에지 기울기 보정값을 구하였다 그런후, 단일척도 기울기 연산자를 사용한 영상에 이들 램프 에지의 위치에만 보정값을 더하여 기준 영상을 만들었다 여기에 마커 영상을 만들어 부식에 의해 재구성하여 얻은 영상을 분수계 변환함으로써, 단일 또는 다중 척도 기울기 연산에 의한 기준 영상을 사용한 경우보다 과분할을 방지할 수 있어서, 분수계 기반 영상 분할 처리 시간의 대부분을 차지하는 영역 병합을 대폭 줄여 총 영상 분할 시간을 단축하였다 기존의 방법들과의 비교 실험을 통하여 제안한 방법은 램프 에지나 에지 밀집 지역의 주요 에지들의 소실 없이 과분할을 줄여 전체 영상 분할 속도를 약 2배 가까이 향상시킬 수 있음을 확인하였다

• Journal of Chest Surgery
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• 제21권6호
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• pp.957-969
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• 1988

There is tendency of increasing number and decreasing age of patients who are indicated for Rastelli operation for their cyanotic congenita heart disease. So there is the need to find the creiterion which saves the patients from early postoperative hemodynamic disturbances. We reviewed the 26 patients who had been performed Rastelli operation at Seoul national University hOipital from January 1981 to June 1988. mean age of the patients was 7.8 $\pm$ 3.4 years (range 2.5-1.5 years), mean body surface area(BSA) 0.79 $\pm$ 0.25 $m^{2}$(range 0.49-1.51 $m^{2}$) and mean hematocrit 57.95 $\pm$ 12%(range 48-80%). We diveded these patients into survived group and died group before postoperative 72 hours, and analysed preoperative arterial oxygen saturation($SaO_{2}$), the ratio of diameter of fight pulmonary artery to ascending aorta(RA:/AA), the ratio of both right and left pulmonary artery diameter to descending thoracic aorta(RPA+LPA/DTA), pulmonary artery index(PA index), cardiopulmonary bypass time, aorta cross-clamping time, postoperative perfusion state and total amount of dopamine infused postoperatively. The results showed that RPA+LPA/DTA and PA index were statistically significatn factors to influence early postoperative cardiac death rate (P<0.05). Especially there were good linear correlations between PA index(X) and perpheral perfusion index(Y)(Y = -1.15 + 0.02 X, r = 0.86, P<0.01) and between PA index(X) and total amount of dopamine infused before postoperative 72 hours(mg/kg, Y)(Y = 61.94 - 0.15 X, r = - 0.80, P<0.01). Also there were tendencies that the higher RPA + LPA/DTA(Y), the betterperipheral perfusion (X) and the lower need of dopamine(X), but no statistical significance. (Y = 0.78 + 1.60 X, r = 0.49, P>0.05) And the discrimant analysis showed that patients with PA index over 221 $mm^{2}$/BSA could undergo correction with 25 per cent of error rate. In conclusion, early postoperative hemodynamic states could be predicted by preoperatively measured PA index, and which can be used as a criterion for Rastelli operation performed on cyanotic congenital heart disease.

• 대한환경공학회지
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• 제33권8호
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• pp.617-622
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• 2011

수질오염총량관리제는 유역에 설정된 목표수질을 달성하기 위해 허용부하량 이내로 오염물질의 배출량을 관리하기 위해 도입되었다. 그 동안 수질오염총량관리제를 시행해오면서 수많은 시행착오와 문제점들이 발생하여 이를 개선하기 위한 제도적, 기술적 보완이 이루어져 왔으나, 제도의 효율적인 시행을 위해 근본적인 개선이 필요한 실정이다. 따라서 본 연구에서는 수질오염총량관리제의 합리적 시행을 위한 개선방안을 새로운 시각에서 제시하고자 한다. 수질오염총량관리제의 시행에 있어 무엇보다도 먼저 지류하천의 수질 유량모니터링을 위한 대상하천의 규모, 측정시기, 항목 및 주기 등을 포함하는 시스템 구축을 통하여 모니터링을 수행하여야 한다. 모니터링 결과를 바탕으로 해당유역의 이수 및 생태목적에 맞도록 대상물질 및 목표수질을 설정하고, 전체유역을 대상으로 기본계획을 수립하여야 한다. 목표수질을 초과하는 유역만을 대상으로 수질 개선을 위한 시행계획을 수립하고, 시행계획에 따른 해당유역의 목표수질 만족여부를 주요내용으로 하는 이행평가를 매년 수행해야 한다. 최종적으로 해당유역에 설정된 목표수질을 만족하지 못하거나, 대상항목 또는 목표수질이 변경되면 동일한 순으로 절차를 반복하게 되고, 해당유역에 설정된 목표수질을 만족하면 해당유역의 수질오염총량관리제를 종료하면 된다.

• 한국대기환경학회지
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• 제33권5호
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• pp.497-514
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• 2017

This study quantitatively analyzes the effects of emission inventory choices on the simulated particulate matter (PM) concentrations and the domestic/foreign contributions in the Seoul Metropolitan Area (SMA) with an air quality forecasting system. The forecasting system is composed of Weather Research and Forecasting (WRF)-Sparse Matrix Operator Kernel Emissions (SMOKE)-Community Multi-Scale Air Quality (CMAQ). Different domestic and foreign emission inventories were selectively adopted to set up four sets of emissions inputs for air quality simulations in this study. All modeling cases showed that model performance statistics satisfied the criteria levels (correlation coefficient >0.7, fractional error <50%) suggested by previous studies. Notwithstanding the apparently good model performance of total PM concentrations by all emission cases, annual average concentrations of simulated total PM concentrations varied up to $20{\mu}g/m^3$ (160%) depending on the combination of emission inventories. In detail, the difference in simulated annual average concentrations of the primary PM coarse (PMC) was up to $25.2{\mu}g/m^3$ (6.5 times) compared with other cases. Furthermore, model performance analyses on PM species showed that the difference in the simulated primary PMC led to gross model overestimation in general, which indicates that the primary PMC emissions need to be improved. The contribution analysis using model direct outputs indicated that the domestic contributions to the annual average PM concentrations in the SMA vary from 44% to 67%. To account for the uncertainty of the simulated concentration, the contribution correction factor method proposed by Bae et al. (2017) was applied, which resulted in converged contributions(from 48% to 57%). We believe this study shows that it is necessary to improve the simulated concentrations of PM components in order to enhance the accuracy of the forecasting model. It is deemed that these improvements will provide more accurate contribution results.

• Journal of Astronomy and Space Sciences
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• 제11권1호
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• pp.71-80
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• 1994

GPS를 이용하여 이온층의 총전자수를 측정하는 방법은 기존의 다른 방법에 비하여 넓은 지역에 대한 이온층의 변화를 보다 정확하게 조사할 수 있다고 알려져 있다. 이 연구에서는 GPS위성으로부터 두 개의 L-band 주파수, L1(1574.42MHz)과 L2(1227.60MHz)에 실려 전송되는 P 코드의 이온층에 의한 전파 도달 시각차이를 이용하여 각각의 위성에 대한 시선방향의 충전자수를 측정하였다. 그리고 이온층이 균질하여 평균높이가 350km라고 가정했을 때, 시선방향이 평균 높이와 교차하는 지점에서의 수직방향 총전자수로 각각 변환하여 이를 평균하는 방법을 택하였다. 국내에서는 이중주파수용 P 코드 수신기가 없는 관계로 국제 공동 GPS 관측망의 핵심 관측소 중 하나인 Taiwan의 TAIW GPS 관측소(N25도, E121.5)에서 관측된 GPS 자료를 이용하였다. 측정된 총전자수의 1일 변화 양상을 NOAA의 SOLAR-DAILY 자료 및 GPS의 이온층 보정 모델 (Klobuchar 1987)과 비교한 결과, 거의 같은 양상이 나타났다. 즉, 총전자소의 값이 낮에슨 높아지고 밤에는 낮아지는 전형적인 1일 변화 곡선을 보였다. 그리고 이 연구방법에 의한 총전자수 측정 정밀도는 SOLAR-DAILY 자료와 비교한 결과, 약 2 TEC인 것으로 추정되었다.

• 분석과학
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• 제15권5호
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• pp.475-481
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• 2002

먹는샘물과 용기 중에 phthalate 및 adipate를 분석하였다. 시료 전처리법으로서 먹는샘물의 경우는 methylene chloride를 용매로 하여 액체-액체 추출법을 사용하였고, 고체 시료는 속 슬렛 추출과 실리카겔 정제법을 사용하였다. 추출 후 농축한 다음 GC-MS (SIM)로 정량하였다. 추출물의 chromatogram은 방해물질이 없고 각 피크는 분리가 잘 되었다. 물 시료의 경우 $0.1{\sim}10{\mu}g/L$의 농도범위에서 $r^2$값이 0.996 이상의, 용기시료의 경우 $1{\sim}1,000{\mu}g/Kg$의 농도범위에서 $r^2$값이 0.994이상의 좋은 직선성을 보였다. 물 시료 중에서 검출한계는 $0.002{\sim}0.010{\mu}g/L$의 범위를 용기 시료 중에서는 $0.01{\sim}0.02{\mu}g/Kg$의 범위를 보였다. 먹는샘물 5 종류, PET병 2 종류, 라벨 2 종류, 병뚜껑 2 종류 그리고 접착제 2 종류를 위의 방법에 따라 분석하였다. 그 결과 국내산 먹는샘물 중에서는 대부분 불검출 되었고 외국산 먹는샘물에서 총 프탈레이트 $1.2{\mu}g/L$의 농도가 검출되어 외국의 경우 긴 유통기간 때문에 높은 것으로 판단되나 인체에 유해한 정도의 농도는 아니었다. 용기 재질 분석에서도 국내산 PET 용기에서 (약 0.55 mg/Kg) 보다 외국산의 경우가 (약 1.2 mg/Kg) 비교적 높은 농도로 검출되었다. 한편 라벨이나 접착제에서는 비교적 높은 농도로 프탈레이트가 함유되어 있는 것으로 나타났다. 본 연구결과 먹는샘물과 용기 중에서 프탈레이트의 분석은 공시료 분석값을 정확히 빼주는 것이 필요하며 PET 시료채취 시에는 라벨과 본드를 제외시켜야 정확한 분석값을 구할 수 있는 것으로 나타났다.

• Journal of Chest Surgery
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• 제24권7호
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• pp.674-684
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• 1991

The surgical treatment of tetralogy of Fallot [TOF] was initiated by Blalock and Taussig in 1945 with the establishment of the subclavian artery to pulmonary artery anastomosis. In an imaginative and daring effort, in 1954, Lillehei and collaborators [1955] using controlled cross-circulation, carried out the first intracardiac repair of TOF by closing the ventricular septal defect [VSD] and relieving the pulmonary stenosis under direct vision. Nowadays, total correction is the ideal operation for treatment of TOF and is accomplished with extracorporeal circulation. And the results of surgery for TOF have steadily improved over the years, thanks to important contributions of many surgeons. Nevertheless because of its protean physiologic and anatomic presentation, TOF continues to offer challenges to cardiologist and cardiac surgeons. Thirty two cases of TOF have undergone total corrective surgery using extracorporeal circulation in the Department of Thoracic & Cardiovascular Surgery, Pusan Paik Hospital, Inje University, from Oct. 1985 to Feb. 1990. Clinical considerations were applied to these cases and the results were obtained as follows. 1. The heart lung machine used for extracorporeal circulation was SarnsO 7000, 5-head roller pump, and the number and type of oxygenators were 10 of bubble type and 22 of membrane type. The mean bypass time was 148.9 minutes and the mean aortic cross clamp time was 123.8 minutes. The GIK [glucose-insulin-potassium] solution was used as cardioplegic solution for myocardial protection during operation. 2. 20 cases were male and 12 were female, the mean age was 8 years old and the mean body weight was 25Kg. 3. The preoperative symptoms were cyanosis [29 cases], squatting [27 cases] and etc. The mean values of preoperative Hb., Hct., and SaO2 were 16.5 gm /dl, 50.3%, and 78.5%. 4. Combined anomalies were noticed in 16 cases [50%]. Among them 10 cases were PFO and 6 cases were ASD. 5. The degree of aorta overriding were 25% in 5 cases, 25 ~ 50% in 22 cases and above 50% in 5 cases. The dPA/Ao [ratio of diameter of pulmonary artery trunk to ascending aorta] were below 25% in 5 cases, 25 ~ 50% in 10 cases, 50 ~ 70% in 6 cases and above 75% in 11 cases. 6. The types of RVOT [right ventricular outflow tract] stenosis were valvular and infundibular in 14 cases [43.6%], diffuse hypoplastic type in 12 cases [37.5%], infundibular in 5 cases, and valvular and supravalvular in 1 case. 7. One stage radical corrective surgery was applied to the all cases. In widening of the RVOT, 3 types of patches were used: MVOP [monocusp ventricular outflow patch, Polystan BioprosthesesO] in 3 cases, knitted Dacron vessel patches in 2 cases, and double layer with bovine pericardium and woven Dacron prosthesis in 26 cases. 8. Postoperative complications were occurred in 15 cases. Among them, low output syndrome were occurred in 10 cases [31.3%] and 2 of them were expired postoperatively.

• 한국초지조사료학회지
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• 제35권3호
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• pp.257-263
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• 2015

This study was conducted to assess the potential of using NIRS to accurately determine the chemical composition and fermentation parameters in fresh coarse sorghum and sudangrass silage. Near Infrared Spectroscopy (NIRS) has been increasingly used as a rapid and accurate method to analyze the quality of cereals and dried animal forage. However, silage analysis by NIRS has a limitation in analyzing dried and ground samples in farm-scale applications because the fermentative products are lost during the drying process. Fresh coarse silage samples were scanned at 1 nm intervals over the wavelength range of 680~2500 nm, and the optical data were obtained as log 1/Reflectance (log 1/R). The spectral data were regressed, using partial least squares (PLS) multivariate analysis in conjunction with first and second order derivatization, with a scatter correction procedure (standard normal variate and detrend (SNV&D)) to reduce the effect of extraneous noise. The optimum calibrations were selected on the basis of minimizing the standard error of cross validation (SECV). The results of this study showed that NIRS predicted the chemical constituents with a high degree of accuracy (i.e. the correlation coefficient of cross validation ($R^2{_{cv}}$) ranged from 0.86~0.96), except for crude ash which had an $R^2{_{cv}}$ of 0.68. Comparison of the mathematical treatments for raw spectra showed that the second-order derivatization procedure produced the best result for all the treatments, except for neutral detergent fiber (NDF). The best mathematical treatment for moisture, acid detergent fiber (ADF), crude protein (CP) and pH was 2,16,16 respectively while the best mathematical treatment for crude ash, lactic acid and total acid was 2,8,8 respectively. The calibrations of fermentation products produced poorer calibrations (RPD < 2.5) with acetic and butyric acid. The pH, lactic acid and total acids were predicted with considerable accuracy at $R^2{_{cv}}$ 0.72~0.77. This study indicated that NIRS calibrations based on fresh coarse sorghum and sudangrass silage spectra have the capability of assessing the forage quality control

• 대기
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• 제29권5호
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• pp.511-523
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• 2019

A new Korean Meteorological Administration (KMA) airborne measurement platform has been established for regular observations for scientific purpose over South Korea since late 2017. CRDS G-2401m analyzer mounted on the King Air 350HW was used to continuous measurement of CO₂, CH₄ and CO mole fraction. The total uncertainty of measurements was estimated to be 0.07 ppm for CO₂, 0.5 ppb for CH₄, and 4.2 ppb for CO by combination of instrument precision, repeatability test simulated in-flight condition and water vapor correction uncertainty. The airborne vertical profile measurements were performed at a regional Global Atmosphere Watch (GAW) Anmyeon-do (AMY) station that belongs to the Total Carbon Column Observing Network (TCCON) and provides concurrent observations to the Greenhouse Gases Observing Satellite (GOSAT) overpasses. The vertical profile of CO₂ shows clear altitude gradient, while the CH₄ shows non-homogenous pattern in the free troposphere over Anmyeon-do. Vertically averaged CO₂ at the altitude between 1.5 and 8.0km are lower than AMY surface background value about 7 ppm but higher than that observed in free troposphere of western pacific region about 4 ppm, respectively. CH₄ shows lower level than those from ground GAW stations, comparable with flask airborne data that was taken in the western pacific region. Furthermore, this study shows that the combination of CH₄ distribution in free troposphere and trajectory analysis, taking account of convective mixing, is a useful tool in investigating CH₄ transport processes from tropical region to Korean region in winter season.

• 한국태양에너지학회 논문집
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• 제33권5호
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• pp.95-104
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• 2013

This study set out to devise an optimized system to take into account life cycle cost(LCC) and ton of carbon dioxide($TCO_2$) by applying the weighted coefficient method(WCM) to "public-purpose" facility buildings according to the mandatory 5% and 11% of new renewable energy in total construction costs and anticipated energy consumption, respectively, based on the changes of the public obligation system. (1) System installation capacity is applied within the same new renewable energy facility investment according to the mandatory 5% of new renewable energy in total construction costs. Both LCC and $TCO_2$ recorded in the descending order of geothermal, solar, and photovoltaic energy. The geothermal energy systems tended to exhibit an excellent performance with the increasing installation capacity percentage. (2) Optimal systems include the geothermal energy(100%) system in the category of single systems, the solar energy(12%)+geothermal energy(88%) system in the category of 2-combined systems, and the photovoltaic energy(12%)+solar energy(12%)+geothermal energy(76%) system and the photovoltaic energy(12%)+solar energy(25%)+geothermal energy(63%) system in the category of 3-combined systems. (3) LCC was the highest in the descending order of photovoltaic, geothermal and solar energy due to the influences of each energy source's correction coefficient according to the mandatory 11% of new renewable energy in anticipated energy consumption. The greater installation capacity percentage photovoltaic energy had, the more excellent tendency was observed. $TCO_2$ recorded in the descending order of geothermal, photovoltaic and solar energy with the decreasing installation capacity of photovoltaic energy. The greater installation capacity percentage a geothermal energy system had, the more excellent tendency it demonstrated. (4) Optimal systems include the geothermal energy(100%) system in the category of single systems, the photovoltaic energy(62%)+geothermal energy(38%) system in the category of 2-combined systems, and the photovoltaic energy(50%)+solar energy(12%)+geothermal energy(38%) system and the photovoltaic energy(12%)+solar energy(12%)+geothermal energy(76%) system in the category of 3-combined systems.