• 대기
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• 제29권4호
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• pp.451-461
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• 2019

Medium-range forecast is highly dependent on ensemble forecast data. However, operational weather forecasters have not enough time to digest all of detailed features revealed in ensemble forecast data. To utilize the ensemble data effectively in medium-range forecasting, representative weather patterns in East Asia in this study are defined. The k-means clustering analysis is applied for the objectivity of weather patterns. Input data used daily Mean Sea Level Pressure (MSLP) anomaly of the ECMWF ReAnalysis-Interim (ERA-Interim) during 1981~2010 (30 years) provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). Using the Explained Variance (EV), the optimal study area is defined by 20~60°N, 100~150°E. The number of clusters defined by Explained Cluster Variance (ECV) is thirty (k = 30). 30 representative weather patterns with their frequencies are summarized. Weather pattern #1 occurred all seasons, but it was about 56% in summer (June~September). The relatively rare occurrence of weather pattern (#30) occurred mainly in winter. Additionally, we investigate the relationship between weather patterns and extreme weather events such as heat wave, cold wave, and heavy rainfall as well as snowfall. The weather patterns associated with heavy rainfall exceeding 110 mm day^-1 were #1, #4, and #9 with days (%) of more than 10%. Heavy snowfall events exceeding 24 cm day^-1 mainly occurred in weather pattern #28 (4%) and #29 (6%). High and low temperature events (> 34℃ and < -14℃) were associated with weather pattern #1~4 (14~18%) and #28~29 (27~29%), respectively. These results suggest that the classification of various weather patterns will be used as a reference for grouping all ensemble forecast data, which will be useful for the scenario-based medium-range ensemble forecast in the future.

• 자원환경지질
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• 제18권2호
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• pp.151-157
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• 1985

Events detected by the KIER microearthquake network operated in the Southern Part of Korea for 265 days in 1982~1984 were reviewed, and some of them were identified to be a dynamite explosion from several construction sites. The purpose of the present work is to determine the crustal structure of the Southern Korea using the time-destance data obtained from such explosion seismic records. The time·distance data can be well explained by a crustal model composed of four horizontal layers of which thickness, p and s-wave velocity ($V_p$ and $V_s$) are characterized as follows. 1st layer (surface) ; 0~2km, $V_p=5.5km/sec$, $V_s=3.3km/sec$ 2nd layer (upper crust) ; 2~15km, $V_p=6.0km/sec$, $V_s=3.5km/sec$ 3rd layer (lower crust) ; 15~29km, $V_p=6.6km/sec$, $V_s=3.7km/sec$ 4th layer (upper mantle) ; 29km~ , $V_p=7.7km/sec$, $V_s=4.3km/sec$ The relatively shallow crust·mantle boundary and low $P_n$ velocity compared with the mean values for stable intraplate region are noteworthy. Supposedely, it is responsible for the high heat flow in the South-eastern Korea or an anomalous subterranean mantle. The mean $V_p/V_s$ ratio calculated from the relation between p-wave arrival and s-p arrival times appears to be 1.735 which is nearly equivalent to the elastic medium of ${\lambda}={\mu}$. However, the ratio tends to be slightly larger with the depth. The ratio is rather high compared with that of the adjacent Japanese Island, and the fact suggests that the underlying crust and upper mantle in this region are more ductile and hence the earthquake occurrences are apt to be interrupted. As an alternative curstal model, a seismic velocity structure in which velocities are successively increased with the depth is also proposed by the inversion of the time·distance data. With the velocity profile, it is possible to calculate a travel time table which is appropriate to determine the earthquake parameters for the local events.

• 농업과학연구
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• 제49권3호
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• pp.679-690
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• 2022

As the supply and demand of pork has become a significant concern in Korea, controlling it has become a critical challenge for the industry. However, compared to the demand for pork, which has relatively stable consumption, it is not easy to maintain a stable supply. As the preparation of measures for a supply-demand crisis response and supply control in the pig industry has emerged as an important task, it has become necessary to establish a stable supply model and create an appropriate manual. In this study, a pork supply prediction model is constructed using reported data from the pig traceability system. Based on the derived results, a method for determining the supply-demand crisis stage using a statistical approach was proposed. From the results of the analysis, working days, African swine fever, heat wave, and Covid-19 were shown to affect the number of pigs graded in the market. A test of the performance of the model showed that both in-sample error rate and out-sample error rate were between 0.3 - 7.6%, indicating a high level of predictive power. Applying the forecast, the distribution of the confidence interval of the predicted value was established, and the supply crisis stage was identified, evaluating supply-demand conditions.

• 한국응용과학기술학회지
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• 제33권3호
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• pp.411-420
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• 2016

The objective of this study was to determine the effect of drinking water containing trimethyl glycine or ascorbic acid on growth performance and blood parameter profiles of duck exposed to scorching heat stress. A total of 480 ducks were randomly assigned to the following eight experiment groups for 42 days : control group C with general water, treatment group 1 (T1) with drinking water containing 100 ppm ascorbic acid, treatment group 2 (T2) with drinking water containing 200 ppm ascorbic acid, treatment group 3 (T3) with drinking water containing 300 ppm ascorbic acid, treatment group 4 (T4) with drinking water containing 400 ppm trimethyl glycine, treatment group 5 (T5) with drinking water containing 800 ppm trimethyl glycine, treatment group 6 (T6) with drinking water containing 1,200 ppm trimethyl glycine, treatment group 7 (T7) with electrolytes of KCl (0.5%) + $NaHCO_3$ (1.0%)+NaCl (0.5%). Our results revealed that the body weights and feed intakes of treatment groups, especially T3 and T6, were increased compared to the control group, where as the feed conversion ratios of treatment groups were decreased (p<0.05). Blood levels of total cholesterol, triglyceride, LDL-C, glucose, AST, ALT and pH in treatment groups were lower compared to those in the control group (p<0.05). Blood levels of red blood cell, platelets profiles, electrolyte and gas in treatment groups were higher compared to those of the control group (p<0.05).

• 대기
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• 제29권2호
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• pp.183-196
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• 2019

High-quality and high-resolution meteorological information is essential to reduce damages due to disastrous weather phenomena such as flash flood, strong wind, and heat/cold waves. There are many meteorological observation stations operated by Korea Meteorological Administration (KMA) in Seoul Metropolitan Area (SMA). Nonetheless, they are still not enough to represent small-scale weather phenomena like convective storm cells due to its poor resolution, especially over urban areas with high-rise buildings and complex land use. In this study, feasibilities to use additional pre-existing networks (e.g., operated by local government and private company) are tested by investigating the effects of network density on the gridded horizontal distribution of two meteorological variables (temperature and precipitation). Two heat wave event days and two precipitation events are chosen, respectively. And the automatic weather station (AWS) networks operated by KMA, local-government, and SKTechX in Incheon area are used. It is found that as network density increases, correlation coefficients between the interpolated values with a horizontal resolution of 350 m and observed data also become large. The range of correlation coefficients with respect to the network density shows large in nighttime rather than in daytime for temperature. While, the range does not depend on the time of day, but on the precipitation type and horizontal distribution of convection cells. This study suggests that temperature and precipitation sensors should be added at points with large horizontal inhomogeneity of land use or topography to represent the horizontal features with a resolution higher than 350 m.

• 농촌의학ㆍ지역보건
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• 제43권1호
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• pp.9-17
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• 2018

농작업 시 고온에 대한 노출 실태를 파악하고, 고온 노출에 대한 인지도를 조사하여 농업인의 고온성질환 예방 방안을 모색하고자 이 연구를 시행하였다. 경주시 일부 농촌 마을을 농작업 중 고온노출 장소로 선정하였다. 여름 동안 총 9회의 환경 측정을 실시하였다. 측정을 통해 열지수와 WBGT를 산출하였고, 이들과 현재 우리나라 기상청에서 폭염 경보 및 주의보의 기준으로 제시하고 있는 일별 최고기온을 비교하였다. 설문조사는 같은 지역 농업인 90명을 대상으로 실시하였다. 설문조사는 일대일 면접조사로 진행되었으며, 설문조사서는 고온 노출 실태, 생활 행태, 병력, 온열질환에 대한 인지도 등에 관한 항목으로 구성하였다. 폭염경보 및 주의보 시 WBGT(Wet Bulb Glove Temperature index)와 열지수의 일치율은 높았으나, 비폭염주의보 시 WBGT가 초과되는 경우가 있었다. 조사대상자는 총 90명이었고, 연령별은 60대 이상이 78명(86.7%)이었다. 작업은 주로 새벽-오전(71.1%)에 하였으며, 하루 야외 작업시간은 4시간 미만(54.4%)이 가장 많았으나, 주기적 휴식을 하는 경우는 23.3%이었다. 온열질환 경험률은 14.4%이었고, 증상으로는 피곤, 무기력, 현기증, 두통, 땀 등의 순이었다. 전반적으로 온열질환 및 폭염주의보에 대한 인지도는 각각 70.0%, 74.4%로 높았다. 정책적으로 폭염주의보 발령 시에는 단순한 기온만 고려할 것이 아니라 WBGT기준과 열지수를 동시에 고려하여야 할 것이다. 농업인에게는 농작업 시 휴식 시간을 주기적, 양적으로 늘려 온열질환을 예방하도록 홍보 및 교육을 하여야 할 것이다.

• 대한원격탐사학회지
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• 제36권5_3호
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• pp.1077-1093
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• 2020

해수면 온도는 전 세계 해양, 기상 현상에 영향을 주고 해양 환경 변화와 생물에게 영향을 주는 중요한 요소이다. 특히, 우리나라 남해안을 비롯한 연안 지역의 경우 어업 및 양식업 등의 수산업이 많이 발달하여, 매년 고수온 현상으로 인한 사회·경제적 피해가 발생하고 있다. 따라서 위성 자료와 같은 광범위한 지역을 감시할 수 있는 자료를 활용한 해수면 온도 및 공간적 분포의 예측기술 개발을 통하여 피해를 예방할 수 있는 시스템을 구축할 필요가 있다. 해수면 온도 예측은 기존의 수치 모델을 통해서 예측을 진행하였지만, 다수의 역학적 요인들을 사용하여 예측 결과 산출 시 복잡함이 존재한다. 최근 기계학습 및 딥러닝 기법이 발달함에 따라 해양 분야의 예측에 적용하는 연구가 진행되고 있다. 본 연구는 그 중 시·공간적인 일관성 및 정확도가 높은 장단기 기억(Long Short Term Memory, LSTM)과 합성곱 장단기 기억(Convolutional Long Short Term Memory, ConvLSTM) 딥러닝 기법을 사용하여 남해지역의 해수면온도 예측 및 2017년부터 2019년까지의 고수온 발생 건에 대해서 예측 결과의 공간 분포와 공간 분포와 예측 가능성에 대해 분석을 하였다. 1일 예측 모델의 정확도는 RMSE 기준으로 ConvLSTM(전체: 0.33℃, 봄: 0.34℃, 여름: 0.27℃, 가을: 0.32℃, 겨울: 0.36℃)이 LSTM 기반의 예측 모델(전체: 0.40℃, 봄: 0.40℃, 여름: 0.48℃, 가을: 0.39℃, 겨울: 0.34℃)보다 우수한 성능을 보였다. 2017년 고수온 발생 사례에 대해 해수면 온도 예측과 고수온 탐지 성능에서 ConvLSTM은 5일까지 경보를 탐지하였지만, LSTM의 경우 2일 예측 이후 해수면 온도를 과소 추정하는 경향이 커짐에 따라 탐지하지 못하였다. 시공간적인 해수면 온도 예측 시 ConvLSTM이 LSTM에 비해 적절한 모델로 판단된다.

• The Journal of Korean Physical Therapy
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• 제13권3호
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• pp.509-527
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• 2001

The Sun's ray is composed of Infrared(49%), Visible light(40%) and Ultra violet(11%), however the ray getting to the earth is FIR(Far infrared; 60%), IR(Infrared; 20%), and UV(Ultra Violet; 20%). Human beings has utilized FIR already from time immemorial. Hershel found out Infrared for the first time. in the Industrial Revolution the Infrared and FIR had been begun to use making products. In these days, with contemporary science FIR would be begun to clear up the implication in the human body and organic compound. IR classified by wavelength three parts NlR, MIR, FIR. There is FIR which is radiated from healthy human body the wave length is 8-l4m. The human body is composed of proteins which get easily changed by a thermal factor (about 42 $^{\circ}$C over). FIR with low temperature can deeply penetrate on the human body composed things without troublesomes, since FIR has effectively operated on the human body at low temperature (35-40 $^{\circ}$C). When FlR penetrated on the human body. it would inhibit the abnormal genes and cells expression, and then information of DNA and RNA would be reexpressed for arranging DNA and RNA abnormal state. As FlR's receptors in the body, it could be presumed that N-glycosyl linkage of purine and deoxyribose, RNA splicing process, and Heat shock protein. To take the FIR which was a optimized wavewlength and strength, at first, we induced the characteristic algorithm and the computerized programing. Then we formed that the formular of optimized FIR with physical, mathematical logic and theory. especially, Plank, Kirchhoff, Wien, Stefan-Boltzmann's logic and law. In the long run, the formular was induced with integration mathematical, since we had to know the molecular wavelength. Based on the induced formular as above, we programmed the optimized FlR radiating computerized program. In this research, we designed the eletronic circuit f3r interfacing with human body to diagnosis and treatment with FIR sensor which radiated FIR wavelength optimized.

• 대기
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• 제30권3호
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• pp.221-236
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• 2020

The Gangneung region has the complicated geographical characteristics being adjacent to East Sea and Taeback mountains, and thus sea breeze could play an important role in local weather in various aspects. This study aims to understand overall characteristics of sea breeze largely based on long-term (2009~2018) ground-based observation data. We also propose a selection criteria of sea breeze occurrence day; 1) daily precipitation is less than 10 mm, 2) surface wind direction is 0~110° (northerly to easterly) for more than 3 hours during the daytime, 3) wind direction is 110~360° for more than 3 hours during the nighttime, and 4) land and sea temperature difference is positive during the daytime, 5) sea and land sea-level pressure difference is more than 0.5 hPa. As a result, a total of 595 days was selected for the past 10 years. The occurrence of sea breeze is the highest in late Spring to early Summer (May to June). The passage time of sea breeze at the inland station (1.6 km farther inland) is one hour later than the coastal station. On the typical sea breeze event of April 12, 2019, the passage speed and duration of sea breeze was 15 km hr^-1 and about 9 hours, respectively, with its depth of about 500 m and its head swelling. The current results emphasize the critical role of sea breeze in forecasting surface temperature and wind, and contribute to relieve heat wave especially in summer in the Yeongdong region.

• 한국해양바이오학회지
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• 제6권2호
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• pp.118-122
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• 2014

The ocean provide great benefits for microalgal mass cultures with maintaining stable temperature due to high specific heat, mixing by wave energy, and providing large area for large-scale microalgae cultures. In this study, we cultivated a marine green microalga, Tetraselmis sp. KCTC12432BP, using marine photobioreactors on the ocean for investigating the effect of $NaHCO_3$ concentration on the biomass productivities and evaluating the potential of ocean microalgae culture. The culture medium consist of three fold concentrated f/2-Si with 4 g/L of $NaHCO_3$, which is dissolved in natural seawater. After 11 days of cultivation, the cultures reached stationary phase at biomass concentration of 1.6 g/L. At that time, $NaHCO_3$ concentration of 0, 2, and 4 g/L were fed to the cultures. The daily productivities of 0.11, 0.19, 0.30 g/L/day were attained with feeding rate of 0, 2, and 4 g/L $NaHCO_3$, respectively. Biomass productivity of Tetraselmis sp. KCTC12432BP was a function of the $NaHCO_3$ feeding rate as expected. This research shows that the microalgae can grow with $NaHCO_3$ as carbon source in marine photobioreactors on the ocean while exploiting various benefits of ocean cultivation.