• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2003년도 춘계학술대회 논문집
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• pp.423-423
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• 2003

The radiative properties of atmospheric aerosol are determined by the mass and chemical characteristics, and optical properties such as aerosol optical depth (AOD), ngstr m parameter ( $\alpha$) and single scattering albedo (SSA). In particular these aerosol optical properties also determine surface temperature perturbation that may give some information in understanding the regional atmospheric radiative forcing. For understanding the radiative forcing and regional surce of aerosol, this paper summarizes and compares the aerosol optical properties results from and compares the atmospheric aerosol optical properties results from two different experiments: Anmyeon 2000 and Jeju 2001. Korea Global Atmosphere Watch Observatory (KGAWO) at Anmyeon island and ACE-Asia super-site at Gosan Jeju island have measured the radiations and aerosols since the year of 2000. The sites are located in the mid-west and south of Korea peninsula where it is strongly affected by the Asian dust coming from China region in every spring. Aerosol optical properties over both sites were measured through the ground-based sun and sky radiometers were analyzed for understanding the radiation and climate properties. Number concentration and chemical components of aerosol were additionally analyzed for the source estimation in the transportation. The frequency distributions of aerosol optical depth are rather narrow with a modal vaiue of 0.38 at both sites. However, the distributions of show one peak (1.13) at Jeju but two peaks (0.63 and 1.13) at Anmyeon. In the cases of Anmyeon, one peak around 0.63 corresponds to relatively dust-free cases, and the second peak around 1.13 characterizes the situation when Asian dust is presented. The correlation between AOD and resulted high correlation on the wide range with high values of optical depth at Anmyeon, otherwise a narrow range of with moderate to low AOD at Jeju. In dust free condition SSA decrease with waveleneth while in the presence of Asian dust SSA either stays neutral or increases slightly with wavelength. The change of surface temperature shows the stronger positive correlations with aerosol optical depth increase at Anmyeon than Jeju. In the chemical properties the aerosol are related to high concentrations in inorganic matters, SO$^4$, NO$_3$, CA2+ in fine and coarse.

• 한국식품영양과학회지
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• 제23권5호
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• pp.767-773
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• 1994

1989년도 국민영양조사의 식품섭취조사에서 조사된 전국규모의 자료를 중심으로총 566종의 식품에 대해 식이성섬유소 분석치를 적용하여 그 섭취량을 분석한결과는 다음과 같다. 식이성섬유소의 섭취량은 전국이 17.53g, 도시평균이 17.91g, 대도시가 18.07g, 중소도시가 17.56g, 농촌이 16.61g으로 나타났으며, 이중 95% 정도를 식물성 식품으로 부터 섭취하고 있었다. 식품군별 식이성섬유소 섭취의 기여도는 채소류>곡류 및 그 제품>해조류>과실류>버섯류>두류 및 그 제품의 순이었다. 곡류 및 그 제품에서 가장 중요한 급원은 쌀로 전국평균이 12.2%였으며, 그 다음이 라면, 식빵, 보리쌀의 순이었으며, 해조류에서 가장 중요한 급원은 미역이었고, 그 다음이 김과 파래였다. 과실류에서는 사과와 감이 버섯류에서는 느타리버섯과 표고버섯이, 두류에서는 콩나물이 식이성섬유소의 중요한 급원이었다. 채소류는 식이성섬유소의 가장 중요한 급원으로, 전국의 경우 32.4%, 도시평균은 31.4%, 대소시에서는 30.8%, 중소도시에서는 33.0%, 농촌에서는 34.8%를 차지하였다. 그 중 가장 중요한 급원은 배추김치와 붉은 고추가 1, 2위를 차지하였다. 전국적으로 식이성섬유소 섭취량 분포를 보면 도수분포(Frequency distribution)의 계급구간을 5g으로 섭취하는 가구로 33.9%를 차지하엿고, 5g 이하나 35g 이상 섭취하는 가구도 0.8%와 5.2%를 나타내었다.

• 한국환경과학회지
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• 제21권1호
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• pp.31-39
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• 2012

The objective of this study is to provide pollutant loads delivery ratio for flow duration in Oenam-cheon watershed, which is upstream watershed of Juam Lake. To calculate the delivery ratio by flow duration, rating curves and discharge-loads curves using measured data were established, then Flow Duration Curve(FDC) and pollutant loads delivery ratio curves were constructed. The results show that the delivery ratios for $BOD_5$ for abundant flow($Q_{95}$), ordinary flow($Q_{185}$), low flow($Q_{275}$), and drought flow($Q_{355}$) were 23.9, 12.7, 7.1, and 2.9%, respectively. The delivery ratios of same flow regime for T-N were 58.4, 31.2, 17.2 and 7.1%, respectively. While, the delivery ratios T-P were 17.3, 7.5, 3.4, and 1.1% respectively. In general, delivery ratio of high flow condition showed higher value due to the influence of nonpoint source pollution. Based on the study results, generalized equations were developed for delivery ratio and discharge per unit area, which could be used for ungaged watershed with similar pollution sources.

• 재무관리연구
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• 제20권2호
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• pp.95-126
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• 2003

주가가 정규분포보다 꼬리가 두꺼운 확률변수인 점, 주가의 변동이 군집화를 이루고 있는 현상, 주가가 장기기억과정에 의하여 생성되고 있다는 점이 실증분석을 통하여 밝혀지고 있다. 주가를 형성시키는 이 세 요소가 하나의 모형내에 통합되지 못하고 있는 실정인데. 이 세 요소가 통합되는 확률과정이 다중프랙탈과정이다. 다중프랙탈과정은 표준브라운 운동과정과 랜덤시간 변형과정의 결합을 통하여 얻게되는 확률과정이다. 이 과정은 Ito형의 확률과정에 포함되지 않는 연속과정인 것이다. 본 논문에서는 주가시계열의 Pareto-Levy 분포성, 분포의 두꺼운 꼬리성질, 시계열상관이 쌍곡선율로 완만하고 무척 더디게 감소하여 장기에 걸쳐서 평균에 회귀하는 장기기억성, 군집화 현상, 거래시간의 통합성을 포괄하는 다중프랙탈과정의 성질을 살펴보고 이 과정이 주가를 생성시키는 과정인지 아닌지를 검정하는데 그 목적을 둔다. 다중프랙탈과정은 표준브라운 운동과 시간변형과정의 통합을 통하여 형성된 확률과정이다. 시간변형과정은 주가의 군집화 현상을 포착하는 과정이다. 표준브라운 운동은 이 운동과 시간 변형과정의 통합화 속에서 분수브라운운동의 성질이 용해되어 장기기억과정을 포착해준다. 다중프랙탈성은 관찰치들의 시간척축이 변함에 따라 발생하는 확률과정의 적률에 가해진 일련의 제약조건이라 할 수 있다. 이 모형은 마팅게일 성질을 만족하는 모형으로 변형시킬 수도 있으며 자기회귀 조건부 이분산 모형을 대체할 수 있는 모형이다. 이 모형에서는 자기상관을 가지고 있지 않은 수익률에도 적용가능하며, 따라서 시장효율성을 점검하는데에도 이용할 수 있다. 이 모형은 축척일치성이라는 성질이 존재하므로 데이터의 총량화가 무리 없이 이루어질 수 있다. 다중프랙탈은 국소축척구성성질을 가지고 있으며, 시간의 흐름에 따라 변할 수 있는 국소축척구성요소를 내포하고 있다. 자본자산의 다중프랙탈 과정을 한국종합주가지수에 적용하였는 바, 이 과정이 한국종합주가 지수의 행동 잘 설명하고 있다. 따라서 한국종합주가지수는 분포의 꼬리의 두꺼움, 자산가격의 군집화현상, 특이한 값, 장기기억을 내포하고 있다.

• 보건행정학회지
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• 제23권2호
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• pp.152-161
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• 2013

Korea has a single National Health Insurance program and all citizens are covered under this program, accounting 97% of the population, approximately 50 million people. Claims submitted by Health care providers are reviewed by Health Insurance Review and Assessment (HIRA) for the reimbursement. HIRA database contains not only individual beneficiary's information, but also healthcare service information such as diagnosis, procedures, prescriptions and tests for them. HRA database has gained attention as importance source for research due to its rich healthcare information and the demand of HIRA database has increased. Due to its tremendous size, however, researchers have had problems in accessing the database to conduct research. To meet this demand, we conducted a study to develop the inpatient sample data from HIRA database for research. This study has two purposes: 1) to determine a needed sample size; 2) to test reliability and validity of the sample data. We determined an adequate sample size to ensure representativeness and generality with additional consideration for convenience of calculation. The minimum sample size was 729,904 for the generality, and 488,861 for representativeness. After considering the convenience of calculation, our final sample size was 13% of the population, which was about 7.7 million beneficiaries. Age (5 years interval) and gender were used as stratification variables for sampling. In order to examine whether this sample data appropriately reflect population, we tested the reliability and validity of the sample data. From the sample data, we computed average expenditure of total claims per inpatient for 2011, frequency of top 30 disease, estimation of the number of stroke patients from the sample data, and then compared them to those from the population. Results confirmed reliability and validity of the sample data.

• 한국대기환경학회지
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• 제23권1호
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• pp.50-63
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• 2007

The development of domestic plant specific emission factors is very important to estimate reliable national emissions management. This study, for the reason, was carried out to obtain advances emission factor for Carbon Dioxide ($CO_2$) by source-specific emission tests from the iron and steel industry sector which is well known as one of the major sources of greenhouse gases ($CO_2$). Emission factors estimated in this study were compared with those of IPCC for evaluation and they were found to be of similar level in the case of $CO_2$. There was no good information available on $CO_2$ plant specific emission factors from the iron and steel industry in Korea so far. The major emission sources of $CO_2$ examined from the iron and steel manufacturing precesses were a hot blast stove, coke oven, sintering furnace, electric arc furnace, heating furnace, and so on. In this study, the concentration of $CO_2$ from the hot blast stove process was the highest among all processes. The $CO_2$ emission factors for a ton of Steel and Iron products (using B-C oil) were estimated to be 0.315 $CO_2$ tonne (by Tier 3 method) and 4.89 $CO_2$ tonne. In addition, emission factor of $CO_2$ for heating furnace process was the highest among all process. Emission factors estimated in this study were compared with those of IPCC for evaluation and they were found to be of similar level in the case of $CO_2$.

• 물과 미래
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• 제26권4호
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• pp.85-95
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• 1993

본 연구의 목적은 도시소유역에서의 부족한 유량 및 NPS 오염물 자료의 확충과 이를 통한 유출과 NPS 오염물 배출 간의 상관관계의 분석 및 월, 년 NPS 부하량 산정에 의한 물질수지의 분석에 있다. 본 연구를 위한 자료의 확충을 위해서 미국 EPA의 SWMM 모형을 사용하였으며, 상관관계의 분석 및 물질수지의 분석은 NPS 오염에 가장 영향이 큰 선행괘천기간을 긴 경우(CASE 1.)와 짧은 경우(CASE 2.)로 분리하여 수행하였으며, 연구 결과를 요약하면 다음과 같다. 1) 사상별 시간자료의 분석 : CASE 1.과 CASE 2. 모두, 유량과 농도간의 상관관계 보다는 유량과 부하량간의 상관관계가 좋았으며, 선형 상관관계보다는 비선형 상관관계가 좋았다. 결과적으로 두 CASE 모두 비유량-비부하율 관계는 비선형 산관관계가 가장 좋았다. 2) 사상별 총량자료의 분석 : CASE 1.은 비누적유량-비누적부하량의 선형상관관계가 CASE 2.는 비선형 상관관계가 좋았다. 3) 유역의 NPS 년비부하량 산정 결과, 년평균 단위 강우량당 비부하량은 CASE 1.이 CASE 2.보다 모든 오염물에서 약 2.5배였다. 4) 호우기와 갈수기의 NPS 오염물의 비교 결과, 갈수기의 CASE 1.의 비중이 훨씬 컸다. 5) NPS 년비부하량과 PS 년비부하량을 비교한 결과, NPS 오염물이 유역 및 하천의 오염에 상당히 기여함을 알 수 있었다.

• 한국측량학회지
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• 제29권3호
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• pp.293-301
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• 2011

전리층에 의한 신호지연 오차는 2000년 5월 SA해제 후 GPS 측위의 가장 큰 오차 요인이다. 이 연구에서는 전리층 오차를 산출하기 위한 방법으로 국토지리정보원 44개소의 상시관측소로부터 제공된 위상평활코드 의사거리 관측값을 이용하여 전리층 총전자수를 추정하였다. 총전자수를 정확하게 추정하기 위해 위성과 수신기의 하드웨어 바이어스인 DCB(Differential Code Bias)를 산출하여 적용하였으며, 적용 효과를 확인하기 위해 GlM을 기준으로 DCB 적용 전 후의 전리층 총전자수를 비교하였다. 그 결과, DCB를 적용했을 때 약 3~4 TECU, 적용하지 않았을 때 약 35~45 TECU의 RMS 오차를 나타냈다. DCB를 적용하여 $1^{\circ}{\times}1^{\circ}$ 공간해상도의격자형 전리층 총전자수 지도를 생성하였으며, 이때 총전자수 추정에 이용되는 상시관측소의 개소 수 증가에 따른 효과를 분석하기 위해 상시관측소의 개소 수를 10개소, 20개소, 30개소, 44개소 순으로 증가시키며 총전자수를 추정하였다. 각 총전자수 지도를 GIM과 비교하여 RMS 오차를 산출한 결과, 10개소의 상시관측소를 이용한 경우 5.3 TECU에서 44개소의 상시관측소를 이용한 경우 3.9 TECU로 감소하는 것을 확인하였다.

• Ocean and Polar Research
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• 제30권4호
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• pp.519-536
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• 2008

The relatively tranquil area within the Gogunsan Archipelago was for the first time investigated preliminarily with respect to modern sedimentological processes in association with the emplacement of the Saemangeum Dyke. Basic sedimentological observations, bathymetry and surface sediments were performed twice during 2006-2008 to compare the results and elaborate changes during that period of time. In addition, sediment dynamical observations were carried out with latest measuring equipment along two transects crossing the entrances of the archipelago, including 12-hour onboard measurements of current, suspended sediments, temperature, and salinity. This dataset was used to reveal hydrodynamic characteristics for spring season April-May and to estimate the direction and relative magnitude of the net flux of suspended sediments. There occurred three depositional areas (A to C) within the archipelago, where sediment texture was also changed. In area A, around Yami Island and the dyke, and area B, in the center of the archipelago, surface sediments became coarsened over the two-year period; sand content increased 5% at the expense of silt content in the former, whereas silt content increased 3% at the expense of clay content in the latter. By comparison, area C in the western entrance of the archipelago shows a textural trend of fining with more silt and clay (combined increase of 5%) at the expense of sand content. The accumulation of sediments in areas A and B is attributable to the sand and silt resuspended from the seabed sediments off sector 4 of the dyke during the winter. The origin of the fine materials depositing on area C is uncertain at present, although suspended sediments moving offshore around the archipelago may be one of the most likely candidates for the source. The temperature of seawater increased rapidly from $9-10^{\circ}C$ in April to $14-16^{\circ}C$ in May, whereas salinity remained more or less constant at 31-32%o during the two months. Both of these parameters showed little variations with depth through a tidal cycle, suggesting good mixing of seawater without any help of significant waves. The consistency of salinity during a tidal cycle also indicates no insignificant effects of freshwater from the rivers Mangyung and Donjin emitting through the opening gap near Sinsi Island. The suspended sediment concentrations were higher at the entrance between Sunyu and Sinsi islands than at the entrance between Hoenggyong and Sinsi islands, ranging from 20 and 30 mg/l and from 5 and 15 mg/l, respectively at the sea surface. Although tidal currents were variable across a transect between Sunyu and Sinsi islands, the currents across the entrance between Hoenggyong and Sinsi islands flowed consistently in the same direction all over the transect during a tidal cycle. The estimation of net flux of suspended sediments indicates that suspended sediments are transferred to the Gogunsan Archipelago mainly through a relatively deep trough adjacent to Sinsi Island toward the shallow area around Yami Island and the dyke.

• 한국대기환경학회지
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• 제22권1호
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• pp.99-106
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• 2006

Aircraft measurements have been executed for the purpose of monitoring the long range transported air pollution and estimation of air pollutant in/out-flux over the Yellow sea. Total 74 missions of measurements have been done since 1997, mainly in spring and fall. The main study domain was over $124^{\circ}$E $/sim$ $124^{\circ}$E, $35^{\circ}$N $/sim$ $37^{\circ}$N below 3,000m. In long-term trends, mixing ratios of $SO_{2}$N were around 2 ppbv expect in summer ( < 1 ppbv). NOx exhibited 24 ppbv and have no clear annual trends over the Yellow Sea. The concentrations of 03 were 51, 58, 41 ppbv in spring, summer and fall-winter, respectively. Backward trajectory was performed for three days to investigate the source regions of the air mass. Six regions were divided around Korea peninsular centering at $36^{\circ}$N, $126^{\circ}$E. I, II, III, IV and V regions represents in sequence northeast China and Siberia, Sandong peninsula and Balhae gulf, Sanghi and southern China, the south Pacific included Jeju island and the East sea included Japan. L region correspond to the airmass from Korea peninsula. Influx of $SO_{2}$N was approximately five times higher than outflux in yearly flux variation and showed a decreasing long-term trend since 1998. NOx outflux was average 0.095 ton/km/hr and three times higher than $SO_{2}$ outflux. In/out flux of 03 showed even distribution in yearly basis except 2002 (influx 5.45 ton/km/hr). The transported amounts from I, II, III regions were much higher than those from other region. In seasonal flux variation, influx levels of gas phases were the lowest in summer and the levels gradually increased from fall toward spring. As a result, transport of pollutants begins from fall and prevails in winter and spring.