• 대한원격탐사학회지
• /
• 제29권5호
• /
• pp.443-459
• /
• 2013

자바 섭입대 위에 존재하는 인도네시아 메라피 화산은 1~5년의 주기를 가지는 화산활동이 활발한 성층화산이다. 대체적으로 화산폭발지수가 1-3정도의 규모로 나타나는데 비해 최근 2010년 분화는 화산폭발지수가 4까지 올라가 386명을 사망자를 유발했다. 본 연구에서는 40년간 지구를 관측해온 Landsat 영상을 이용하여 18년 동안 메라피 화산의 지표변화를 관측하였다. 연구를 위해 1994년 7월 6일부터 2012년 9월 1일까지 총 55장의 Landsat-5,7 영상을 수집하였으며, 밴드조합영상을 통해 화산쇄설류의 흐름이 시간에 따라 이동함을 확인하였다. 화산쇄설류가 덮고 있는 지역을 추출하기 위해서, COST model을 이용한 대기보정 후 감독분류를 수행하였으며, 그 결과 CVP 보고서에 기재된 화산쇄설류의 분화 방향과 추출된 화산쇄설류 영역의 변화가 거의 일치했다. NASA에서 제공하는 Landsat-5,7 위성의 열적외선 밴드를 이용한 온도 추출 기법을 적용하여 분화구 지역의 평균 지표온도를 산출한 결과, 분화 전 지표 온도가 급격히 상승하고, 분화 후 온도가 하강하는 양상을 반복적으로 나타냈다. 비록 기상조건에 따른 영상획득에 제약이 있지만, 장기간 발생된 메라피 화산의 지표변화를 확인하는데 있어서 Landsat 위성 영상이 매우 유용한 도구임을 확인했다.

• 한국수자원학회논문집
• /
• 제40권4호
• /
• pp.299-311
• /
• 2007

최근 들어 세계의 연중 기후 변화에 주된 요인으로써 엘니뇨와 같은 현상이 매우 잦아졌다. 많은 기상수문학자들이 강수와 유량에 대한 엘니뇨 남방진동의 영향에 대해 연구하고 있지만, 수문변량들은 큰 지역적 변동을 갖고 있기 때문에 결정적인 인과관계를 찾아내는데 있어서 많은 어려움이 있다. 본 연구에서는 엘니뇨-남방진동과 한국에서의 수문변량들 간의 계절석 관계를 고찰하였다. 엘니뇨-난방진동을 정량적으로 표현해 주는 지수로써 남방진동지수를 사용하였고, 월강수량 자료, 월평균기온 자료 그리고 댐의 월유입량 자료를 표준정규분포를 가지는 표준정규지수로 변환하여 사용하였다. 계절적 관계를 파악하기 위해 난방진동지수와 수문변량의 월 자료는 봄 (3월-5월), 여름(6윌-8월), 가을(9월-11월) 그리고 겨울 (12윌-2월)로 분류되었다. ENSO episode에 대한 수문변량들의 조건부 초과확률과 분포형태를 바탕으로 분석을 수행한 결과 전반적으로 Warm ENSO episode의 경우 강수량 증가와 기온 상승과 관련이 있고, Cold ENSO episode의 경우 강수량 감소와 기온 하강과 관계가 있다. 그러나 일부 지역에서는 이러한 전반적인 결과와 상이한 결과가 나타나기도 하였다.

• 산업경영시스템학회지
• /
• 제39권1호
• /
• pp.25-30
• /
• 2016

It is critical to forecast the maximum daily and monthly demand for power with as little error as possible for our industry and national economy. In general, long-term forecasting of power demand has been studied from both the consumer's perspective and an econometrics model in the form of a generalized linear model with predictors. Time series techniques are used for short-term forecasting with no predictors as predictors must be predicted prior to forecasting response variables and containing estimation errors during this process is inevitable. In previous researches, seasonal exponential smoothing method, SARMA (Seasonal Auto Regressive Moving Average) with consideration to weekly pattern Neuron-Fuzzy model, SVR (Support Vector Regression) model with predictors explored through machine learning, and K-means clustering technique in the various approaches have been applied to short-term power supply forecasting. In this paper, SARMA and intervention model are fitted to forecast the maximum power load daily, weekly, and monthly by using the empirical data from 2011 through 2013. $ARMA(2,\;1,\;2)(1,\;1,\;1)_7$ and $ARMA(0,\;1,\;1)(1,\;1,\;0)_{12}$ are fitted respectively to the daily and monthly power demand, but the weekly power demand is not fitted by AREA because of unit root series. In our fitted intervention model, the factors of long holidays, summer and winter are significant in the form of indicator function. The SARMA with MAPE (Mean Absolute Percentage Error) of 2.45% and intervention model with MAPE of 2.44% are more efficient than the present seasonal exponential smoothing with MAPE of about 4%. Although the dynamic repression model with the predictors of humidity, temperature, and seasonal dummies was applied to foretaste the daily power demand, it lead to a high MAPE of 3.5% even though it has estimation error of predictors.

• 한국균학회지
• /
• 제40권1호
• /
• pp.19-38
• /
• 2012

2004년 4월부터 2010년 10월까지 내장산 국립공원 고등균류를 조사한 결과는 다음과 같다. 진균문의 담자균아문 48과 158속 451종, 자낭균아문 13과 26속 39종, 점균문 4과 7속 7종이 조사되었으며, 대부분의 고등균류는 담자균아문 중 모균아강에 속하는 것으로 나타났다. 가장 많이 발생된 균류는 송이버섯과로 72종이었으며, 무당버섯과(43종), 구멍장이버섯과(41종), 그물버섯과(40종), 끈적버섯과(35종), 광대버섯과(28종)순이었다. 미기록종이라 판단되는 종은 무당버섯과 1종(Lactarius vietus), 압정버섯과 1종(Ionomidotis frondosa), 트리코코마과 1종(Penicilliopsis clavariaeformis), 망사점균과 1종(Fuligo septica) 등 총 4과 4속 4종이 조사되었다. 서식환경별 분포에서는 외생균근성버섯이 15과 36속 193종(38.8%), 낙엽 및 목재부후균은 36과 107속 196종(39.4%), 지상균은 24과 51속 99종(19.9%) 및 기타 3과 4속 9종(1.8%)인 것으로 나타났다. 월별 분포에서는 7월이 가장 많은 종수가 조사되었고 8월, 9월 순으로 나타났으며, 11월의 분포가 가장 적은 것으로 나타났다. 기후 환경별 요인에 있어 대부분의 고등균류는 평균온도 $23^{\circ}C$이상, 최저온도 $20^{\circ}C$이상, 최고온도 $29^{\circ}C$이상일 때, 상대습도는 73% 이상일 때, 월 강수량는 200 mm 이상일 때 종 발생이 높아지는 것으로 나타났다. 특히, 외생균근성버섯인 광대버섯과, 그물버섯과 및 끈적버섯과 등 외생균근성버섯은 최고온도 $32^{\circ}C$이상에서 유의성이 낮아지는 것으로 나타나 평균온도, 최저온도, 상대습도 및 강수량 등에 비해 종 발생에 많은 영향을 주는 것으로 나타났다.

• 한국농림기상학회지
• /
• 제18권3호
• /
• pp.120-126
• /
• 2016

본 연구는 유사한 입지에서 생육한 소나무와 굴참나무 임분의 토양 이산화탄소($CO_2$)와 이들 방출에 영향을 미치는 환경요인인 토양 온도, 토양 수분, 토양 pH, 전기전도도, 토양 유기탄소 농도 등을 2015년 3월부터 2016년 2월까지 1년 동안 조사하였다. 토양 $CO_2$ 방출량의 월별 변화는 두 임분 사이에 차이가 있어 하절기인 6월과 7월의 경우, 굴참나무 임분이 소나무 임분에 비해 유의적으로 높았으나, 타 계절은 차이가 없었다. 연 평균 토양 $CO_2$ 방출량의 경우, 굴참나무 임분이 $2.27{\pm}0.22{\mu}mol\;m^{-2}s^{-1}$로 소나무 임분의 $1.63{\pm}0.12{\mu}mol\;m^{-2}s^{-1}$ 에 비해 높게 나타났으며, 연 평균 토양 온도와 토양 수분함량도 굴참나무 임분이 소나무 임분에 비해 높았다. 토양 환경요인 중 토양 온도와 토양 $CO_2$ 방출량은 지수함수 관계(P<0.05)가 있었으며, $Q_{10}$ 값의 경우, 굴참나무 임분이 3.35로 소나무 임분 2.72에 비해 높아 토양 온도 상승 시, 굴참나무 임분의 토양 $CO_2$ 방출량이 소나무 임분에 비해 더 크게 증가하는 것으로 나타났다.

• 한국환경과학회지
• /
• 제23권11호
• /
• pp.1851-1862
• /
• 2014

It is well known that urban relative humidity has continuous decreasing trend owing to the influence of urbanization. The change of relative humidity is directly influenced by two factors, namely, temperature effect and water vapor effect in various urban effects. In this study, the temperature and the water vapor effects on the relative humidity change were analyzed by using monthly mean relative humidities for a long period(1961~2013) in Busan and Daegu. The major results obtained in this study can be summarized as follows. Firstly, the urban dryness was caused mainly by water vapor effect in summer. But, for the other seasons, the urban dryness is mainly due to the temperature effect. Secondly, the relative humidity in Busan is on the decrease until now. This phenomenon is similar to another Korean huge cities such as Seoul, Daejeon and Incheon.

• Journal of the korean society of oceanography
• /
• 제39권1호
• /
• pp.72-95
• /
• 2004

The Yellow Sea is characterized by relatively shallow water depth, varying range of tidal action and very complex coastal geometry such as islands, bays, peninsulas, tidal flats, shoals etc. The dynamic system is controlled by tides, regional winds, river discharge, and interaction with the Kuroshio. The circulation, water mass properties and their variability in the Yellow Sea are very complicated and still far from clear understanding. In this study, an effort to improve our understanding the dynamic feature of the Yellow Sea system was conducted using numerical simulation with the ROMS model, applying climatologic forcing such as winds, heat flux and fresh water precipitation. The inter-annual variability of general circulation and thermohaline structure throughout the year has been obtained, which has been compared with observational data sets. The simulated horizontal distribution and vertical cross-sectional structures of temperature and salinity show a good agreement with the observational data indicating significantly the water masses such as Yellow Sea Warm Water, Yellow Sea Bottom Cold Water, Changjiang River Diluted Water and other sporadically observed coastal waters around the Yellow Sea. The tidal effects on circulation and dynamic features such as coastal tidal fronts and coastal mixing are predominant in the Yellow Sea. Hence the tidal effects on those dynamic features are dealt in the accompanying paper (Kim et at., 2004). The ROMS model adopts curvilinear grid with horizontal resolution of 35 km and 20 vertical grid spacing confirming to relatively realistic bottom topography. The model was initialized with the LEVITUS climatologic data and forced by the monthly mean air-sea fluxes of momentum, heat and fresh water derived from COADS. On the open boundaries, climatological temperature and salinity are nudged every 20 days for data assimilation to stabilize the modeling implementation. This study demonstrates a Yellow Sea version of Atlantic Basin experiment conducted by Haidvogel et al. (2000) experiment that the ROMS simulates the dynamic variability of temperature, salinity, and velocity fields in the ocean. However the present study has been improved to deal with the large river system, open boundary nudging process and further with combination of the tidal forcing that is a significant feature in the Yellow Sea.

• 한국보건간호학회지
• /
• 제12권1호
• /
• pp.116-131
• /
• 1998

This study was undertaken to obtain the menstrual patterns and menstrual discomforts in women university students. For the data collection, self-administered questionnaire survey was made from December 10, 1996 to January 20, 1997 among the 180 women university students in Seoul. The resultant data were processed by SAS program for frequency, proportion, and chi-square test. The results of this study are as follows ; 1) The mean age of the subjects was 20.6 years old. The mean height was 162cm and weight was 52.3Kg. $26.9\%$ of the subjects responded that they had experienced the unbalanced diet, $56\%$ the irregular meal, $39.6\%$intermittent dizziness, and $63.4\%$ the premenstrual syndrome. $53.7\%$ had feeling that skin temperature of their four extremities was 'a little lower than others'. The mean BMI(Body Mass Index) was 19.8, 'normal level' was $41.8\%$. $18.7\%$ responded that their characters were 'introspective ones'. The mean age of menache was 13.8 years old. The subjects responded that the mean number of pads they used per day during menstrual periods was 4.6 sheets. The mean duration of menstruation was 5.4 days, $10.4\%$ responded that their menstrual cycles were 'extremely regular', $44.8\%$ was 'regular', $36.6\%$ was 'a little irregular', and $8.2\%$ was 'extremely irregular'. Out of them who had experienced the dysmenorrhea, $21.3\%$ had family history of dysmenorrhea in connection with their mother and $35.0\%$ in their sisters. The mean of the first time that they experienced dysmenorrhea was 15 years old. $94\%$ of the subjects responded that they had experienced the dysmeorrhea. $47.6\%$ of the subjects responded that they experienced the dysmenorrhea 'monthly' and $52.4\%$ 'intermittently'. $53.0\%$ of them who had experienced dysmenorrhea responded that dysmenorrhea was the severest 'on the first menstrual day' and $22.4\%$ 'on the second day'. $48.8\%$ of them who had experienced dysmenorrhea responded that the most painful region was 'low abdomen'. $40\%$ of them who had experienced dysmenorrhea responded that they used 'analgesics' to soothe dysmenorrhea, $24.8\%$ used nothing, $18.4\%$ lay in their beds or slept, and $12\%$ made their 'low abdomen' warm. $70.3\%$ who had used analgesics because of dysmenorrhea took analgesics 'one or two times per month', $25.7\%$ 'intermittently', and $4.0\%$ more than 3 times per month. The analgesics which they used were 'geworin$(33.8\%)$,' 'penzal$(32.4\%)$', 'tyrenol$(18.9\%)$', and 'aspirin$(4.2\%)$'. $(47.9\%)$ of them who took analgesics because of dysmenorrhea responded that the duration of analgesics effect was '4 to 8 hours'. $15.1\%$ of them who experienced dysmenorrhea responded that they had visited the hospital. 2) The incidence of premenstrual syndrome was no significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 3) The incidence of dysmenorrhea was significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 4) The incidence of analgesics usage was significant difference according to the BMI, subjects with low BMI took more analgesics than those with normal BMI (p<.05). The incidence of analgesics usage was significant difference in accordance with pattern of meal. The women who had a meal regularly took more analgesics than those who had a meal irregularly(p<.05). But the incidence of analgesics usage was no significant difference in accordance with the unbalanced diet, characters, the incidence of dizziness, skin temperature of four extremities, the incidence of premenstrual syndrome.

• Ocean and Polar Research
• /
• 제25권3호
• /
• pp.237-247
• /
• 2003

The temporal dynamics of the meiofauna community in Marian Cove, King George Island were observed from January 22 to October 29 1996. Generally, 14 taxa of metazoan meiofauna were found. Nematodes were dominant comprising 90.12% of the community, harpacticoid 6.55%, and Kinorhynchs 1.54%. Meiofauna abundance increased monthly from January to May 1996, while varying in abundance after August 1996. Overall mean abundance of metazoan meiofauna was $2634ind./10cm^2$ during the study periods, which is about as high as that found in temperate regions. Nematodes were most abundant representing $2399ind./10cm^2$. Mean abundance of harpacticoids, including copepodite and nauplius was $131ind./10cm^2$ by kinorhynchs $(26ind./10cm^2)$. The overall abundance of other identified organisms was $31ind./10cm^2$ Other organisms consisted of a total of 11 taxa including Ostracoda $(6ind./10cm^2)$, Polycheata $(7ind./10cm^2)$, Oligochaeta $(8ind./10cm^2)$, and Bivalvia $(6ind./10cm^2)$. Additionally, protozoan Foraminifera occurred at the study area with a mean abundance of $263ind./10cm^2$. Foraminiferans were second in dominance to nematodes. The dominant taxa such as nematodes, harpacticoids, kinorhynchs and the other tua were trained and extensively scattered in the map through the Kohonen network. The temporal pattern of the community composition was most affected by the abundance dynamics of kinorhynchs and harpacticoids. The neural network model also allowed for simulation of data that was missing during two months of inclement weather. The lowest meiofauna abundance was found in August 1996 during winter. The seasonal changes were likely caused by temperature and salinity changes as a result of meltwater runoff, and the physical impact by passing icebergs.

• 한국지형학회지
• /
• 제20권3호
• /
• pp.95-107
• /
• 2013

한라산 아고산대 표고 1,710m 지점의 나지에서 동결기를 중심으로 212일간 지상 55cm 높이의 기온과 지중 2cm, 10cm 및 20cm 깊이의 지온을 관측하여 주빙하성 지형형성환경을 조사하였다. 관측기간의 평균기온은 $-0.1^{\circ}C$이며, 깊이별 평균지온은 2cm $1.8^{\circ}C$, 10cm $2.6^{\circ}C$, 20cm $3.2^{\circ}C$이다. 2cm 깊이에서는 1월부터 3월까지 영하의 월평균지온이 관측되었으나 다른 깊이에서는 출현하지 않았다. 동결융해 사이클의 출현횟수는 55cm 높이에서 72회인 반면 지중 2cm 깊이에서 17회, 10cm 깊이에서 8회, 20cm 깊이에서 3회로 지중으로 내려가면서 크게 감소하였다. 지상과 2cm 깊이에서의 동결융해는 일일 주기가 탁월한 반면 10cm와 20cm 깊이에서는 수일 주기로 출현하였다. 또한 2cm 깊이에서 12월 중순~4월 중순, 10cm 깊이에서 2월 말~4월 중순, 20cm 깊이에서 4월 초순~중순에 일평균지온이 대체로 $0^{\circ}C$ 밑으로 내려가는 계절적 동결기가 출현하였다. 관측지점은 1월부터 4월 초순까지 55cm 이상의 눈으로 덮여 있다가 4월 16일에 전부 사라졌다. 12월 하순 2cm 깊이에 형성된 계절적 동토층은 적설의 단열효과로 인하여 3월 말~4월 초에 10cm 깊이에 도달하였다. 4월 7일부터 14일까지 깊이 20cm를 넘는 최대동결심을 보이나 이후 급속하게 융해되어 17일 이후 계절적 동토층은 출현하지 않았다. 융해진행기에도 잔설이 남아 있는 관측지점에는 융해진행기보다 동결진행기에 주빙하 프로세스가 더 탁월하게 진행되며, 일주기성 동결융해 사이클의 발생심도와 최대동결심을 고려하면 한라산 아고산대의 사면물질이동은 주로 동상포행에 의해 발생한다.