• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.1
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• pp.45-50
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• 2005

This study was conducted to measure and understand the exchange of CO₂ and water in a rice canopy. Eddy covariance system was installed on a 10m tower along with other meteorological instruments. CO₂ flux and surface energy balance were measured throughout the whole growing season in 2003 over a typical paddy field in Icheon, Korea. During the early growth stage in May and June, most of net radiation was partitioned to latent heat flux with daytime Bowen ratio of 0.3 to 0.7. Evapotranspiration (i.e., daily integrated latent heat flux) typically ranged from 3 to 4 mm d/sup -1/, with even higher rates on sunny days. Daily integrated net ecosystem exchange (NEE) of CO₂ increased with increasing solar radiation and leaf area index (LAI). The NEE was especially high during the stages of young panicle formation and heading. On 1 June 2003, when the rice field was flooded, it was a weak sink of atmospheric CO₂ with an uptake rate of 9.1 gm/sup -2/d/sup -1/. Despite frequent rainy and cloudy conditions in summer, maximum NEE of 36.2 gm/sup -2/d/sup -1/ occurred on 31 July prior to heading stage. As rice crop senesced after early September, the NEE decreased.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.434-442
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• 2017

The UV light in sunlight breaks down the chemical bonds in a polyolefin polymer through a process called photodegradation, ultimately causing cracking, chalking, colour changes, and loss of physical properties such as impact strength, tensile strength, elongation, and others. UV absorbers are used to prevent or terminate the oxidation of plastics by UV light. They are receptive to UV radiation and dissipate the energy harmlessly as heat. Benzotriazoles and benzophenones are used mainly in polyolefins such as polyethylene and polypropylene. In this study, we have developed a method for the analysis of 12 UV absorbers, which are Uvinul 3000, Cyasorb UV 24, Uvinul 3040, Tinuvin 312 and P, Seesorb 202, Chimassorb 81, Tinuvin 329, 234, 326, 328 and 327, migrated from the food packaging materials into four food simulants for aqueous, acidic, alcoholic and fatty foods. The UV absorbers in food simulants were determined by reversed-phase high performance liquid chromatograph-ultraviolet detector with 310 nm after solid-phase extraction with a hydrophilic-lipophilic balance (HLB) cartridge or dilution with isopropanol. The analytical method showed a good linearity of coefficient ($R^2{\geq}0.99$), limits of detection (0.049~0.370 mg/L), and limits of quantification (0.149~1.120 mg/L). The recoveries of UV absorbers spiked to four food simulants ranged from 70.05% to 110.13%. The developed method would be used as a reliable tool to determine concentrations of the migrated UV absorbers.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.227-235
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• 2015

Using eddy covariance method, net ecosystem exchange (NEE) of $CO_2$ ($F_{CO_2}$), $H_2O$ (LE), and sensible heat (H) can be approximated as the sum of eddy flux ($F_c$) and storage flux term ($F_s$). Depending on strength and distribution of sink/source of scalars and magnitude of vertical turbulence mixing, the rates of changes in scalars are different with height. In order to calculate $F_s$ accurately, the differences should be considered using scalar profile measurement. However, most of flux sites for agricultural lands in Asia do not operate profile system and estimate $F_s$ using single-level scalars from eddy covariance system under the assumption that the rates of changes in scalars are constant regardless of the height. In this study, we measured $F_c$ and $F_s$ of $CO_2$, $H_2O$, and air temperature ($T_a$) using eddy covariance and profile system (i.e., the multi-level measurement system in scalars from eddy covariance measurement height to the land surface) at the Chengmicheon farmland site in Korea (CFK) in order to quantify the differences between $F_s$ calculated by single-level measurements ($F_s_{-single}$ i.e., $F_s$ from scalars measured by profile system only at eddy covariance system measurement height) and $F_s$ calculated by profile measurements and verify the errors of NEE caused by $F_s_{-single}$. The rate of change in $CO_2$, $H_2O$, and Ta were varied with height depending on the magnitudes and distribution of sink and source and the stability in the atmospheric boundary layer. Thus, $F_s_{-single}$ underestimated or overestimated $F_s$ (especially 21% underestimation in $F_s$ of $CO_2$ around sunrise and sunset (0430-0800 h and 1630-2000 h)). For $F_{CO_2}$, the errors in $F_s_{-single}$ generated 3% and 2% underestimation of $F_{CO_2}$ during nighttime (2030-0400 h) and around sunrise and sunset, respectively. In the process of nighttime correction and partitioning of $F_{CO_2}$, these differences would cause an underestimation in carbon balance at the rice paddy. In contrast, there were little differences at the errors in LE and H caused by the error in $F_s_{-single}$, irrespective of time.

• Korean Journal of Environmental Agriculture
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• v.8 no.1
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• pp.30-36
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• 1989

To determine irrigated water temperature under the rice plant canopy, micrometeorological elements air temperature, relative humidity, water temperature, solar radiation, and the rice leaf area index the rice plant canopywere measured. Water temperature under the canopy was also estimated from these data. The results are as follows ; 1. Maximum and minimum temperatures of water in the paddy field were higher about $1-2^{\circ}C$ than those of air temperature. 2. Mean water temperature under the canopy became lower than mean air temperature when the leaf area indices were greater than 4, because of decreased light penetration rates 3. Penetration amounts of net radiation under the canopy can be estimated by an exponential equation 4. Estimated water temperatures under the canopy by a combination method model was adaptable in Suweon, a plain area, but its accuracy was lower in Jinbu, an alpine area.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.667-675
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• 2018

Increasing emissions regulations and demand of high-efficiency cars that travels a lot of distance with less fuel, there is growing interest in Energy Consumption Efficiency. Korean energy consumption efficiency compute combined Fuel Economy by driven city & highway driving mode and present final Energy Consumption Efficiency as using 5-cycle correction formula. Energy consumption efficiency is computed Carbon-balance-method, when used burning fuel play a key role in vehicle performance & Energy Consumption Efficiency. In Korea, vehicle fuel is circulate by Petroleum and Petroleum Alternative Business Act, there is property difference in quality standard because petroleum sector's refine method or type of crude oil. It does not appear a big difference according to fuel, because it sets steady quality standard, it may affect the performance of automobile. Thus, in research We purchase a few diesel fuel which circulated in the market in summer season though directly-managed-gas station by petroleum sector, resolve property each of fuel, we compute Fuel Economy each of them. We analyze into change depend on applying for property as nowadays utilizing Energy Consumption Efficiency calculating formula of gasoline and diesel fuel. As result, Density each of sample fuel has a maximum difference roughly 0.9%, net heat value each of sample fuel has difference 1.6%, result of current Energy Consumption Efficiency each of sample fuel has a difference roughly 1% at city drive mode, 1.4% at highway drive mode. Result of use gasoline calculator formula shows less 6% result than nowadays utilizing Energy Consumption Efficiency calculating formula, each of sample's Energy Consumption Efficiency shows maximum roughly 1.4% result in city & highway drive mode.

• The Journal of Dong Guk Oriental Medicine
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• v.7 no.2
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• pp.81-95
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• 1999

Among oriental medicine,s literatures, through Hwang-Je-Nae-Kyung(黃帝內徑) to Chung(淸), I extracted contents related to atrophy syndrome(?證). And studied it,s pathophysiology, therapy and treatment. Then, I concluded that result same below 1. The pathophysiologies of atrophy syndrome are lung heat(肺熱) & decreasing of it,s circulation, making liver and stomach weaken & difficulty it's circulation, injurious to liver and kidney & atrophy of bonemarrow and muscle. 2. The most important point of atrophy syndrome therapy is Yang-Myung(陽明). The Priority of therapy is stomach & liver,s balance. And then we must protect acquired human function & clean humidity & temperature of Yang-Myung(陽明). under the principle of decreasing south organ,s function & protecting north organ,s function, we should Ja-Yeum-Chung-Yeul(滋陰淸熱). so remove temperature of lung & protect liver and kidney & make strong stomach. 3. Among the therapy of atrophy syndrome in literatures Yi-Jin-Tang(二陳湯), Sa-Gun-Ja-Tang(四君子湯), Sa-Mul-Tang-Je(四物湯劑), Ho-Jam-Hwan(虎蠶丸), Dong-Won-Geun-Bo-Hwan(東垣健步丸) and Chung-Jo-Tang(淸燥湯) were many. These make strong spleen & dry humidity organ using Sa-Gun-Ja-Tang(四君子湯)and Yi-Jin-Tang(二陳湯) by Dog-Cheu-Yang-Myung(獨取陽明) method. Sa-Mul-Tang(四物湯), Phellodendri cortex(黃柏), Radix sophorae flavescentis(苦蔘), Carapax Testudinis(龜板) bitter taste make strong Yeum(陰) & decrease Yang(陽) so important human muscle powerful. Ho-Jam-Hwan(虎蠶丸), Dong-Won-Geun-Bo-Hwan(東垣健步丸), Chung-Jo-Tang(淸燥湯) make Chung-Yeul-Jo-Seup(淸熱燥濕), protect liver and kidney & strong muscle and bone. Besides Gum-Gang-Hwan(金剛丸), Yi-Myo-Hwan(二妙丸), Nok-Gak-Geu-Hwan(鹿角膠丸)&Ga-Mi-Sa-Geun-Hwan(加味四斤丸) were used in treatment of atrophy syndrome.

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.7-12
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• 2013

Environmental measurements in the many different types of horticultural farms were carried out to evaluate the ventilation performance for multi-span plastic greenhouses according to the eaves height, the number of spans, the existence of side wall vents and the position of roof vents. Hydroponic tomatoes were being cultivated in all experimental greenhouses, and ventilation rates of the greenhouses were analyzed by the heat balance method. It showed that the ventilation rate in the greenhouse with 4 m eaves height increased about 22% compared to the greenhouse with 2 m eaves height. The ventilation rate in the greenhouse with 9 spans decreased about 17% compared to the greenhouse with 5 spans. In the greenhouse with 9 spans, if there were no side wall vents, the ventilation rate showed about a third of the case that side wall vents were open. Overall, as the eaves height was higher and the number of spans was smaller in multi-span greenhouses, the natural ventilation performance was better. And the ventilation performance was best in the greenhouse which the eaves height was high and the position of roof vents was ridge, not gutter. Therefore, in order to maximize the natural ventilation performance, multi-span plastic greenhouses need to improve their structures such as that make the eaves height higher, place the roof vents on the ridge, install the side wall vents as much as possible, and the number of spans is limited to about 10 spans.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.6
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• pp.518-524
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• 1990

Actual evapotranspiration was measured over rice paddy field by Bowen ratio heat balance method and based on this, investigated was the reliability of actual evapotranpiration estimation from Class-A Pan and small pan evaporation and reference evapotranspiration calculated by modified Penman-Monteith model. Crop coefficients based on Class-A Pan and small pan evaporation and reference evapotranspiration by modified Penman-Monteith model were averaged to be 1.57. 1.10 and 1.49 over the whole rice growing season, respectively. Their respective coefficients of variation were 28.7. 22.7 and 12.8 percent, respectively. Crop coefficient based on modified Penman-Monteith model varied in good agreement with the trend of leaf area development, being greatest around heading stage.

• Journal of Korean Medical classics
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• v.21 no.1
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• pp.1-11
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• 2008

Jangjahwa(張子和) was influenced by "Hwangjenaegyeong(黃帝內經)" and Yuhagan(劉河間)'s theory, and other classics. Also, his clinical experience was helpful to theorize his thought. Thus, he improved medical theory by combining previous medical theory and his own experience. The essence of his thought is the importance of pathogenic Gi[邪氣] as the cause of disease and is Sambeop(三法) of Hantoha(汗吐下) as the methodology for removing pathogenic Gi[邪氣] away. He regarded pathogenic Gi as the cause of disease, and eliminated pathogenic Gi for the remedy. Namely, Sambeop(三法) of Hantoha(汗吐下) was selected as the best efficient method for driving pathogenic Gi away. Sambeop of Jangjahwa(張子和) have different meaning from previous one. Traditionally, Diaphoretic Therapy[汗法] was regarded as therapy for exogenous disease[外感病], and its effect was regarded as Balhanhaepyo(發汗解表). Emetic therapy[吐法] was throwing up Dameumsuksik(痰飮宿食) of stomach and above diaphragm. Purgation therapy[下法] means Tongbyeon(通便), Hajeok(下積), Sasil(瀉實), Chuksu(逐水) were regarded as therapy for Yangmyeongsiljeung(陽明實證) of Sanghan(傷寒). He submitted a new extensive concept of Sambeop adding traditional one, and expanded the application range of Sambeop. All methods, can cause circulation of Gihyeol(氣血) by opening the 'Hyeonbu(玄府)', like Moxibution therapy[灸薰], Steaming[蒸], Washing[洗],Heat therapy[慰], Cauterization[烙], Acupuncture therapy[鍼刺], Stone needling, Physical and breathing exercise[導引], Massage[按摩] were regarded as Diaphoretic Therapy[汗法]. Especially, he thought that Diaphoretic Therapy and venesection[瀉血] have same medical implication. If we examine the process of pushing out pathogenic Gi[邪氣] by means of Sambeop(三法), we can find the intermediation, that is circulation of Gihyeol(氣血). Its meaning is implied in the word of 'opening Hyeonbu(玄府)'. He thought that the circulation of Gihyeol(氣血) is the key to control health. Gihyeol(氣血) was circulated well under the physiological balance, but it was not circulated well under the invasion of pathogenic Gi[邪氣]. In other words, pathogenic Gi is the immediate cause of bad circulation of Gihyeol(氣血) and disease. Naturally, the doctor must remove pathogenic Gi that cause bad circulation for healing by means of Sambeop(三法). In my opinion, because the ultimate goal of Jangjahwa(張子和) was circulation of Gihyeol(氣血) by removing pathogenic Gi[邪氣], the concept of Sarnbeop(三法) could be expanded.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.156-172
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• 2020

The purpose of this study was to predict road surface temperature using high-resolution solar radiation data. The road surface temperature prediction model (RSTPM) was applied to predict road surface temperature; this model was developed based on the heat-balance method. In addition, using SOLWEIG (SOlar and LongWave Environmental Irradiance Geometry-model), the shadow patterns caused by the terrain effects were analyzed, and high-resolution solar radiation data with 10 m spatial resolution were calculated. To increase the accuracy of the shadow patterns and solar radiation, the day that was modeled had minimal effects from fog, clouds, and precipitation. As a result, shadow areas lasted for a long time at the entrance and exit of a tunnel, and in a high-altitude area. Furthermore, solar radiation clearly decreased in areas affected by shadows, which was reflected in the predicted road surface temperatures. It was confirmed that the road surface temperature should be high at topographically open points and relatively low at higher altitude points. The results of this study could be used to forecast the freezing of sections of road surfaces in winter, and to inform decision making by road managers and drivers.