• 대기
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• 제19권2호
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• pp.213-226
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• 2009

In order to investigate the characteristics of Changma over the Korean peninsula, KEOP-2007 IOP (Intensive Observing Period) was conducted from 15 June 2007 to 15 July 2007. KEOP-2007 IOP is high spatial and temporal radiosonde observations (RAOB) which consisted of three special stations (Munsan, Haenam, and Ieodo) from National Institute of Meteorological Research, five operational stations (Sokcho, Baengnyeongdo, Pohang, Heuksando, and Gosan) from Korea Meteorological Administration (KMA), and two operational stations (Osan and Gwangju) from Korean Air Force (KAF) using four different types of radiosonde sensors. The error statistics of the sensor of radiosonde were investigated using quality control check. The minimum and maximum error frequency appears at the sensor of RS92-SGP and RS1524L respectively. The error frequency of DFM-06 tends to increase below 200 hPa but RS80-15L and RS1524L show vice versa. Especially, the error frequency of RS1524L tends to increase rapidly over 200 hPa. Systematic biases of radiosonde show warm biases in case of temperature and dry biases in case of relative humidity compared with ECMWF (European Center for Medium-Range Weather Forecast) analysis data and precipitable water vapor from GPS. The maximum and minimum values of systematic bias appear at the sensor of DFM-06 and RS92-SGP in case of temperature and RS80-15L and DFM-06 in case of relative humidity. The systematic warm and dry biases at all sensors tend to increase during daytime than nighttime because air temperature around sensor increases from the solar heating during daytime. Systematic biases of radiosonde are affected by the sensor type and the height of the sun but random errors are more correlated with the moisture conditions at each observation station.

• 생태와환경
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• 제46권1호
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• pp.10-17
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• 2013

History of Instream Flow Incremental Methodology (IFIM) Following the large reservoir and water development era of the mid-twentieth century in North America, resource agencies became concerned over the loss of many miles of riverine fish and wildlife resources in the arid western United States. Consequently, several western states began issuing rules for protecting existing stream resources from future depletions caused by accelerated water development. Many assessment methods appeared during the 1960's and early 1970's. These techniques were based on hydrologic analysis of the water supply and hydraulic considerations of critical stream channel segments, coupled with empirical observations of habitat quality and an understanding of riverine fish ecology. Following enactment of the National Environmental Policy Act (NEPA) of 1970, attention was shifted from minimum flows to the evaluation of alternative designs and operations of federally funded water projects. Methods capable of quantifying the effect of incremental changes in stream flow to evaluate a series of possible alternative development schemes were needed. This need led to the development of habitat versus discharge functions developed from life stage-specific relations for selected species, that is, fish passage, spawning, and rearing habitat versus flow for trout or salmon. During the late 1970's and early 1980's, an era of small hydropower development began. Hundreds of proposed hydropower sites in the Pacific Northwest and New England regions of the United States came under intensive examination by state and federal fishery management interests. During this transition period from evaluating large federal reservoirs to evaluating license applications for small hydropower, the Instream Flow Incremental Methodology (IFIM) was developed under the guidance of the U.S. Fish and Wildlife Service (USFWS).

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 추계학술대회 논문집
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• pp.343-343
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• 2002

This study examines the influence of long-range transport of dust particles and air pollutants on both local/regional DMS oxidation chemistry and the distribution of sulfur compounds at Jeju Island (33.17$^{\circ}$ N. 126.10$^{\circ}$ E) during the Asian dust-storm(ADS) period in April 2001. The atmospheric concentrations of these sulfur species were measured at a ground station on Jeju Island. Korea as Part of the ACE-Asia intensive operation. Three ADS events were observed during the periods of 10-12, 13-14. and 25-26 April. respectively. The concentrations of DMS and CS$_2$ were higher during the ADS period than during the non-Asian-dust-storm (NADS) period. Conversely. a difference in SO$_2$ levels during the ADS period was not distinguishable from those during the NADS period. The diurnal variation pattern of DMS observed was largely different from that in the remote marine boundary layer. DMS loss by NO$_3$ in the atmospheric boundary layer was dominant due to significantly high NOx levels influenced by the long-range transport of pollutants from East Asia to Jeju Island The DMS maximum during the ADS period was observed in the late afternoon. The oceanic fluxes of DMS during the ADS and NADS periods were estimated to be 5.7$\pm$2.3 and 2.9 (+2.8/-1.5) mole m$^{-2}$ day$^{-1}$ . respectively. The contribution of oxidized DMS to SO$_2$ levels at Jeju Island during the study period was found to be insignificant.

• 지역사회간호학회지
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• 제15권4호
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• pp.618-627
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• 2004

Purpose: To investigate the dental health status of kindergarten children according to their oral health behavior. Method: The subjects were 172 kindergarten children aged 5. A structured questionnaire was used for dental health behavior and oral health status were examined by dentist and bacteria in salivary. Result: 1. Mean score of oral health behavior of children was 4.69 points (SD1.65) with the highest score being 13. No significant differences were observed according to sex, except using tooth paste. A total 71.5% of subjects brushed their tooth twice a day, 9.9% of them once a day, 18.6% of them three times a day, 19.2% of children brushed their teeth after breakfast and lunch, 89.5% of then after dinner, 5.8% of them before going to bed, 18.6% of children brushed correctly, 79.7% of them used tooth paste with fluorine, 3.5% of them regularly examined oral cavity, 84.4% of them took cariogenic food without any restrain, 67.1% of them were observed with oral cavity by their mother. 2. Streptococcus mutans and lactobacilli in the saliva was $3.66({\times}106CFU/m{\ell})\;and\;1.05({\times}103CFU/m{\ell})$, respectively. No significant differences were observed according to sex, while lactobacilli were significantly lower in those children who had regular dental examinations. 3. The index of plaque was 1.56 and the boys were significantly higher than the girls. The mean dft was 4.99. No significant differences were observed according to sex, while the children whose oral cavity was observed regular were significantly lower than those who were not observed. Conclusion: As a whole the practice of oral health behavior of the kindergarten children was poor, and regular dental examinations and oral cavity observations affect their dental health status. These results suggest that intensive dental health education was needed not only for the pre-school children but also their parents and teachers.

• 한국광물학회지
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• 제23권2호
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• pp.99-106
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• 2010

금번 연구에서는 2009년 1월 1일부터 12월 31일 사이에 대전광역시 유성구 지역에서 확보한 강수 시료를 대상으로 강수에 의한 오염 희석 규명을 시도하였다. 강수여과물에 대해 등온잔류자화(Isothermal remanent magnetization) 측정과 현미경 분석 및 정성적인 화학 성분 분석을 실시하였다. 비강수일에 포집한 먼지 시료와 황사발생일에 채취한 먼지 시료도 비교를 위해 실험에 사용하였다. 자화특성 실험과 현미경 관찰 결과를 바탕으로 판단하면, 강수에서 여과된 고체 시료에 존재하는 자성 물질은 자철석이다. 관찰된 자성 물질의 특이한 형태(구형/타원체형)와 탄소 함유를 고려하면, 인위적인 연소에 의해 형성된 자철석이라 해석된다. 강수에서 여과된 고체 시료의 등온잔류자화는 일반 먼지보다도 낮고 황사에 비해서는 현저히 낮은데, 이는 강수에 의해 발생하는 상당한 양의 자성물질 희석 효과라 판단된다.

• Journal of Trauma and Injury
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• 제34권3호
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• pp.155-161
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• 2021

Purpose: The coronavirus disease 2019 (COVID-19) pandemic has necessitated a redistribution of resources to meet hospitals' service needs. This study investigated the impact of COVID-19 on a regional trauma center in South Korea. Methods: We retrospectively reviewed cases of polytrauma at a single regional trauma center in South Korea between January 20 and September 30, 2020 (the COVID-19 period) and compared them to cases reported during the same time frame (January 20 to September 30) between 2016 and 2019 (the pre-COVID-19 period). The primary outcome was in-hospital mortality, and secondary outcomes included the number of daily admissions, hospital length of stay (LOS), and intensive care unit (ICU) LOS. Results: The mean number of daily admissions decreased by 15% during the COVID-19 period (4.0±2.0 vs. 4.7±2.2, p=0.010). There was no difference in mechanisms of injury between the two periods. For patients admitted during the COVID-19 period, the hospital LOS was significantly shorter (10 days [interquartile range (IQR) 4-19 days] vs. 16 days [IQR 8-28 days], p<0.001); however, no significant differences in ICU LOS and mortality were found. Conclusions: The observations at Regional Trauma Center, Pusan National University Hospital corroborate anecdotal reports that there has been a decline in the number of patients admitted to hospitals during the COVID-19 period. In addition, patients admitted during the COVID-19 pandemic had a significantly shorter hospital LOS than those admitted before the COVID-19 pandemic. These preliminary data warrant validation in larger, multi-center studies.

• 한국환경과학회지
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• 제31권4호
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• pp.329-339
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• 2022

Better understanding the mechanism of black ice occurrence on the road in winter is necessary to reduce the socio-economic damage it causes. In this study, intensive observations of road weather elements and surface information under the influence of synoptic high-pressure patterns (22^nd December, 2020 and 29^th January, and 25^th February, 2021) were carried out using a mobile observation vehicle. We found that temperature and road surface temperature change is significantly influenced by observation time, altitude and structure of the road, surrounding terrain, and traffic volume, especially in tunnels and bridges. In addition, even if the spatial distribution of temperature and road surface temperature for the entire observation route is similar, there is a difference between air and road surface temperatures due to the influence of current weather conditions. The observed road temperature, air temperature and air pressure in Nongong Bridge were significantly different to other fixed road weather observation points.

• 한국지구과학회지
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• 제42권5호
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• pp.496-503
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• 2021

한반도 남해안 지역의 여름철 대기 안정도 특성을 분석함으로써, 한반도 특성에 맞는 강수 예측을 위한 대기 안정도 지수의 정량적인 임계값을 도출하고자 하였다. 보성 표준기상관측소에서 관측한 2019년도 여름철 라디오존데 집중관측자료를 분석에 사용하였으며, 총 관측자료는 243개 이다. 강수 유무 및 중규모 대기 현상에 대한 대기 안정도를 분석하기 위해서, 대류가용잠재에너지(Convective Available Potential Energy, CAPE)와 폭풍지수(Storm Relative Helicity, SRH)를 비교하였으며 특히 SRH 분석은 고도 별로 총 4개의 층으로(0-1, 0-3, 0-6, 0-10 km) 세분화하였다. 강수 유무에 따른 분석은 강수가 없는 경우, 강수발생 전 12시간, 강수 발생 시로 구분하여 수행하였다. 그 결과, 2019년도 보성에서 발생한 여름철 강수 예측에는 CAPE 보다 SRH가 더 적합하며 0-6 km SRH가 약한 토네이도가 발생가능한 기준과 같은 150 m² s^-2 이상일 경우 강수가 발생한 것으로 분석 된다. 또한, 장마와 태풍 기간의 대기 안정도를 분석한 결과를 보면, 일반적으로 SRH는 대기 깊이가 두꺼워 질수록 값이 커지는 데 반해서 0-10 km SRH 평균값 보다 0-6 km 의 SRH 값이 더 크게 나타났다. 따라서, 2019년도 보성에서 발생한 태풍에 의한 강수를 판별하는 데는 0-6 km 의 SRH 값이 더 효과적이라고 할 수 있다.

• 기술혁신학회지
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• 제16권1호
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• pp.63-100
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• 2013

과학데이터는 사실, 관찰, 이미지, 컴퓨터프로그램결과, 기록, 측량 또는 경험(논거, 이론, 테스트 또는 가설 또는 기타 연구물에 기초한)의 형태에서 생성되는 데이터를 의미한다. 연구패러다임이 데이터 중심의 연계 융합연구로 전환되면서 이러한 과학데이터에 대한 중요성과 그 가치는 매우 높아지고 있다. 과학데이터가 창의적인 연구개발을 위해 효율적으로 재사용될 수 있기 위해서는 공유와 활용을 위한 관리체계의 구축이 필수적이다. 과학데이터의 공유와 활용을 위한 관리체제의 구축은 국가적 차원에서 이루어져야 하지만, 우리나라의 경우 관리체제의 수준은 호주, 미국, 중국 또는 유럽에 비해서 연계성으로나 효율성으로나 내실을 기하지 못하고 있다. 호주, 미국, 중국 등은 국가차원에서 관련 기관을 통해 과학데이터를 수집, 관리 및 유지하는 등 데이터 활용을 적극적으로 추진하기 위하여 중장기적인 정책수립, 법제도 정비, 기반시설에 대한 투자를 지속적으로 확대하고 있다. 본 연구는 효율적이고 공정한 과학데이터의 공유 및 활용을 위한 국가적인 관리체계구축 및 이를 뒷받침할 수 있는 법제도를 정비함에 있어서 해외 관련 입법례 및 정책동향에 관하여 살펴보고, 향후 우리나라의 대응방안을 제시하였다.

• Asian Journal of Atmospheric Environment
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• 제9권4호
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• pp.237-246
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• 2015

We conducted intensive observations of ozone, CO, $NO_x$ (=NO and $NO_2$), $NO_y$ (total odd nitrogen species including particulate nitrate) and total nitrate (the sum of gaseous $HNO_3$ and particulate nitrate) at Cape Hedo, Okinawa, Japan, from 19 March to 3 April, 2009, to investigate ozone production during long-range transport from the Asian continent. Ozone production efficiency (OPE) was used to evaluate photochemical ozone production. OPE is defined as the number of molecules of ozone produced photochemically during the lifetime of a $NO_x$ molecule. OPE is calculated by the ratio of the concentration increase of ozone to that of $NO_z$ ($=NO_y-NO_x$). Average OPE during observation was estimated to be $12.6{\pm}0.5$, but concentrations of ozone increased nonlinearly with those of $NO_z$. This non-linearity suggests that OPE depends on air mass origin and $NO_z$ concentrations. There were very different values of OPE for the same air mass origin, so that only the air mass origin alone does not control OPE. OPE was low when $NO_z$ concentration was high. We examined the correlation between $NO_z$ and $CO/NO_y$ ratios, which we used instead of the ratio of non-methane hydrocarbons (NMHCs) to $NO_x$. The $CO/NO_y$ ratios decreased with increasing $NO_z$ concentrations. These results indicate that competition reactions of OH with NMHCs and $NO_2$ are the rate determining steps of photochemical ozone production during long-range transport from the Asian continent to Cape Hedo, for high concentrations of nitrogen oxides.