• 한국산림과학회지
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• 제86권3호
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• pp.334-341
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• 1997

솔잎혹파리 유충(幼蟲)은 대부분(大部分) 강우시(降雨時)에 낙하(落下)하는 생태적(生態的) 특성(特性)을 이용(利用), 추기(秋期)의 자연낙하기(自然落下期) 동안 피해임지내(被害林地內)의 수관상부(樹冠上部)에 분수장치(噴水裝置)를 설치(設置)하고 강수량별(降水量別), 강수시기별(降水時期別) 및 강수시각별(降水時刻別)로 인공강수(人工降水)를 실시(實施)하여 인공강수(人工降水)가 솔잎혹파리 유충낙하(幼蟲落下)에 미치는 영향(影響)을 분석검토(分析檢討), 인공강수(人工降水)에 의(依)한 새로운 천적사육용(天敵飼育用) 솔잎혹파리 유충채집법(幼蟲採集法)을 개발(開發)코자 하였으며 얻어진 결과(結果)는 다음과 같다. 1. 인공강수(人工降水)에 의(依)한 솔잎혹파리 천적사육용(天敵飼育用) 유충채집법(幼蟲採集法)은 매우 효과적(效果的)이었으며 유충채집(幼蟲採集)에 필요(必要)한 적정강수량(適正降水量)은 5.3-9.4mm, 이때에 소요(所要)된 살수량(撒水量) 및 살수시간(撒水時間)은 각각(各各) $8,000-16,000{\ell}$와 180-360분(分) 이었다. 2. 인공강수(人工降水)에 의(依)한 효과적(效果的)인 유충채집시기(幼蟲採集時期)는 중부지방(中部地方) 소나무림(林)의 경우 11월(月) 초순(初旬)부터 중순(中旬)까지 약(約) 20일간(日間)이며 이 기간(期間)에 낙하(落下)한 유충수(幼蟲數)는 전체(全體) 낙하수(落下數)의 93.4%였다. 3. 하루중에 있어서의 인공강수(人工降水)에 의(依)한 유충낙하(幼蟲落下)는 강수시각(降水時刻)에 영향(影響)을 받지 않았다. 4. 인공강수(人工降水)에 의(依)한 유충(幼蟲)의 채집시기별(採集時期別) 천적기생율(天敵寄生率)은 11월(月)의 것이 비교적(比較的) 높았으며 12월(月) 채집분(採集分)은 다소 떨어지는 경향(傾向)을 보였다. 5. 인공강수(人工降水)에 의(依) 유충채집적지(幼蟲採集跡地)의 1년후(年後)의 밀도변동(密度變動)은 채집전(採集前)과 비교(比較)하여 약(約) 34%의 밀도감소효과(密度減少效果)가 있었다. 6. 인공강수(人工降水)에 의(依)한 유충채집방법(幼蟲採集方法)은 현행방법(現行方法)인 충영채집법(蟲癭採集法)에 비(比)하여 약(約) 14-50%의 채집비용(採集費用)(경제적(經濟的)) 절감효과(節減效果)가 있었다.

• 한국환경과학회지
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• 제15권12호
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• pp.1125-1139
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• 2006

The cluster analysis of diurnal precipitation patterns is performed by using daily precipitation of 59 stations in South Korea from 1973 to 1996 in four seasons of each year. Four seasons are shifted forward by 15 days compared to the general ones. Number of clusters are 15 in winter, 16 in spring and autumn, and 26 in summer, respectively. One of the classes is the totally dry day in each season, indicating that precipitation is never observed at any station. This is treated separately in this study. Distribution of the days among the clusters is rather uneven with rather low area-mean precipitation occurring most frequently. These 4 (seasons)$\times$2 (wet and dry days) classes represent more than the half (59 %) of all days of the year. On the other hand, even the smallest seasonal clusters show at least $5\sim9$ members in the 24 years (1973-1996) period of classification. The cluster analysis is directly performed for the major $5\sim8$ non-correlated coefficients of the diurnal precipitation patterns obtained by factor analysis In order to consider the spatial correlation. More specifically, hierarchical clustering based on Euclidean distance and Ward's method of agglomeration is applied. The relative variance explained by the clustering is as high as average (63%) with better capability in spring (66%) and winter (69 %), but lower than average in autumn (60%) and summer (59%). Through applying weighted relative variances, i.e. dividing the squared deviations by the cluster averages, we obtain even better values, i.e 78 % in average, compared to the same index without clustering. This means that the highest variance remains in the clusters with more precipitation. Besides all statistics necessary for the validation of the final classification, 4 cluster centers are mapped for each season to illustrate the range of typical extremities, paired according to their area mean precipitation or negative pattern correlation. Possible alternatives of the performed classification and reasons for their rejection are also discussed with inclusion of a wide spectrum of recommended applications.

• 한국지구과학회지
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• 제24권1호
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• pp.22-29
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• 2003

Temporal and spatial variability of precipitation (P), evaporation (E), and moisture balance (P-E; precipitation minus evaporation) has been investigated over the tropical ocean during the period from January 1998 to July 2001. Our data were analyzed by the EOF method using the satellite P and E observations made by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) and the Special Sensor Microwave/Imager (SSM/I). This analysis has been performed for two three-year periods as follow; The first period which includes the El Ni${\tilde{n}}$o in early 1998 ranges from January 1998 to December 2000, and the second period which includes the La Ni${\tilde{n}}$o events in the early 1999 and 2000 (without El Ni${\tilde{n}}$o) ranges from August 1998 to July 2001. The areas of maxima and high variability in the precipitation and in the P-E were displaced from the tropical western Pacific and the ITCZ during the La Ni${\tilde{n}}$o to the tropical middle Pacific during the El Ni${\tilde{n}}$o, consistent with those in previous P studies. Their variations near the Korean Peninsula seem to exhibit a weakly positive correlation with that in the tropical Pacific during the El Ni${\tilde{n}}$o. The evaporation, out of phase with the precipitation, was reduced in the tropical western Pacific due to humid condition in boreal summer, but intensified in the Kuroshio and Gulf currents due to windy condition in winter. The P-E variability was determined mainly by the precipitation of which the variability was more localized but higher by 2-3 times than that of evaporation. Except for the ITCZ (0-10$^{\circ}$N), evaporation was found to dominate precipitation by ${\sim}$2 mm/day over the tropical Pacific. Annual and seasonal variations of P, E, and P-E were discussed.

• 대기
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• 제20권3호
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• pp.229-238
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• 2010

The 1,000~500 hPa thickness and the $0^{\circ}C$ isotherm at 850 hPa have been used as the traditional predictors for wintertime precipitation-type forecasts. New approaches are taking on added significance as preexistence method of determination for wintertime precipitation-type exhibits more or less prevalent false alarms. Moreover thicknesses and thermodynamic profiles from ordinary upper-air observation were not adequate to monitor the atmospheric structure. In this regard, Microwave radiometric profiler microwave radiometer is useful in wintertime precipitation-type forecasts because radiometric measurements provide soundings at high temporal resolution. In this study, the determination and the predictability of wintertime precipitation-type were examined by using the calculated thicknesses, temperature of 850 hPa (T850) from a microwave radiometer, and surface observation at National Center for Intensive Observation of severe weather (NCIO) located at Haenam, Korea. The critical values for traditional predictors (thickness of 1000~500 hPa and T850) were evaluated and adjusted to Haenam region because snow rarely occurred with a 1000-500 hPa thickness > 5,300 m and T850 > $-10^{\circ}C$. Three thicknesses (e.g., 1,000~850, 1000~700, and 850~700 hPa thickness), T850, surface air temperature, and wet-bulb temperature were also evaluated as the additional predictors. A simple nomogram and a flow chart were finally designed to determine the wintertime precipitation-type using the microwave radiometer. The skill scores for the predictability of precipitation-type determination are considerably improved and the predictors showed the temporal variations in 12 hours before precipitation. We can monitor the hit and run snowfall in winter successful by realtime watch of the predictors, especially in commutes of big cities.

• Korean Chemical Engineering Research
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• 제59권3호
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• pp.379-392
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• 2021

본 연구에서는 초음파 캐비태이션 버블와 가스 버블를 이용한 파클리탁셀의 개선된 아세톤-물 분별침전 공정을 개발하였다. 전통적 방법에 비해 침전에 소요되는 시간이 20~25배 단축되었다. 또한 파클리탁셀의 침전물 크기는 3.5~5.5배 감소하였으며 파클리탁셀의 확산 계수는 3.5~6.7배 증가하였다. 초음파 캐비태이션 버블을 이용한 침전의 경우 초음파 파워는 증가할수록, 침전 온도는 감소할수록 침전 속도 상수는 증가하였다. 가스 버블을 이용한 침전의 경우 가스 유량은 증가할수록, 침전 온도는 감소할수록 침전 속도 상수는 증가하였다. 열역학적 해석을 통해 개선된 분별침전은 비자발적 발열 공정이었다.

• 핵의학기술
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• 제27권2호
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• pp.133-136
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• 2023

Purpose: Prolactin in the blood is separated into three types, and over 90% of prolactin presents as a double monomer (23 KDa). Rarely, it can exist in the size of big prolactin (150 KDa), which is called macroprolactin and is known as an autoantibody complex. When macroprolactin accounts for more than 60% of prolactin in the blood, it is called macroprolactinemia. The presence of such macroprolactin was first reported in a patient with hyperprolactinemia but without typical symptoms. Macroprolactinemia is emerging as an important cause of idiopathic hyperprolactinemia. The polyethylene glycol (PEG) precipitation method using the property of precipitating large-molecular-weight proteins is simple and recently has been widely used as a screening test. The results are in good agreement with the results of gel chromatography. The purpose of this study was to confirm the measurement method and reference value verification of monomeric prolactin in blood prolactin using the PEG precipitation method. Materials and Methods: For 40 examinees who visited the Gangnam Center of Seoul National University Hospital in 2021, the prolactin level was verified using radioimmunoassay (RIA). For macroprolactinemia PEG precipitation method, 25% PEG (molecular weight 6000kDa) solution and serum were mixed in equal amounts in a test tube, then left at room temperature for 20 minutes and centrifuged at 4℃ for 30 minutes (1500g). The prolactin level was measured in the supernatant. Results : After confirming that more than 90% of the 40 tested samples within the reference range <25 ng/mL, the same value as the reference value for prolactin was applied. Since the concentration of monomeric prolactin in serum from which macroprolactin has been removed from blood is diluted 1:1 with PEG, our laboratory is currently reporting the result by multiplying the result by a dilution factor of 2. Conclusion: Radioimmunoassay using PEG precipitation method using the property of precipitating large molecular weight proteins is simple and effective for quantitative measurement of monomeric prolactin in blood prolactin.

• 한국농공학회논문집
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• 제52권4호
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• pp.83-91
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• 2010

Generally, the GCM (General Circulation Model) data by IPCC climate change scenarios are used for future weather prediction. IPCC GCM models predict well for the continental scale, but is not good for the regional scale. This paper tried to generate future temperature and precipitation of 8 scattered meteorological stations in South Korea by using the MIROC3.2 hires GCM data and applying LARS-WG downscaling method. The MIROC3.2 A1B scenario data were adopted because it has the similar pattern comparing with the observed data (1977-2006) among the scenarios. The results showed that both the future precipitation and temperature increased. The 2080s annual temperature increased $3.8{\sim}5.0^{\circ}C$. Especially the future temperature increased up to $4.5{\sim}7.8^{\circ}C$ in winter period (December-February). The future annual precipitation of 2020s, 2050s, and 2080s increased 17.5 %, 27.5 %, and 39.0 % respectively. From the trend analysis for the future projected results, the above middle region of South Korea showed a statistical significance for winter precipitation and south region for summer rainfall.

• 대한토목학회논문집
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• 제34권4호
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• pp.1139-1150
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• 2014

본 연구에서는 M-PRISM 모형을 이용하여 $1km{\times}1km$ 공간해상도 일강수량 추정에 대한 적용성을 검토하였다. 또한 회귀모형을 이용하여 M-PRISM 모형 매개변수를 추정하였으며, 잭나이프 방법을 이용하여 모형을 검증하였다. 기상청 385개 강수 관측지점에 대하여 M-PRISM을 이용하여 일강수량을 추정하고 PRISM 모형과 비교하였다. 비교결과, 강수의 정량적 크기를 추정에서는 두 모형에서 뚜렷한 차이를 찾아볼 수 없었으나, 강수의 발생빈도 추정에 있어서는 M-PRISM 모형이 더 우수한 결과를 나타내었다. 따라서 본 연구에서 제안한 M-PRISM 모형은 고해상도의 일강수량을 추정함에 있어서 매우 유용하게 사용될 수 있을 것으로 판단된다.

• 대한금속재료학회지
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• 제49권12호
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• pp.917-923
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• 2011

Dissolution and precipitation behaviors of complex carbonitrides in austenite of a V-Nb microalloyed steel were quantitatively examined through electrical resistivity measurement and transmission electron microscopy. The electrical resistivity increased with solution treatment temperature up to $1240^{\circ}C$ and then was saturated at $225n{\Omega}m$ for a holding time of 10 min. The electrical resistivity method was also used to quantitatively measure the isothermal precipitation kinetics of the complex carbonitrides in austenite. Nb-rich precipitates were observed in austenite at the early stages of precipitation, but Nb was replaced by V up to the equilibrium amount within the precipitates with further holding time. The time-temperature-precipitation diagram showed a C-type curve; nose temperature and its incubation time were $900^{\circ}C$ and 100 s, respectively.

• 한국재료학회지
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• 제12권11호
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• pp.840-844
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• 2002

A spherical $BaMgAl_{10}$ $O_{17}$ :Eu phosphor has been synthesized by a multi-step precipitation route. In order to successfully synthesize the phosphor with spherical shape, the hydrated-alumina particles should be controlled for spherical shape. In this process, the hydroxypropyl cellulose (HPC) was used as a dispersing reagent. This reagent plays an important role in that the particles were controlled to have the uniform size of sub-micron. The final product prepared by the multi-step precipitation method maintained spherical shape with uniform size of 0.4$\mu\textrm{m}$. It can be seen in X-ray diffraction patterns, formation of the single phase of $BaMgAl_{10}$ $O_{17}$ :Eu phosphor prepared by the multi-step precipitation method at $1350^{\circ}C$. Also, the emission spectra of spherical $BaMgAl_{O}$ $10_{17}$ :Eu phosphor in the present case was compared with those of commercially-available blue phosphor under VUV (Vacuum Ultra Violet) excitation. The luminescence process of the $BaMgAl_{10}$ $O_{17}$ :Eu phosphor is characterized by the $4f^{6}$$5d^1$longrightarrow4f$^{7}$ transition (blue) of the $Eu^{2+}$ ion acting as an activating center and the maximum luminescence intensity was obtained by reduction treatment at 145$0^{\circ}C$.