• Ocean and Polar Research
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• v.32 no.3
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• pp.291-297
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• 2010

In the summer of 2008 (August 4-14), vertical and horizontal distributions of inorganic nutrients and dissolved organic carbon (DOC) were measured in the southwestern East Sea. Concentrations of DOC were determined for the first time in the southwestern East Sea using the high-temperature combustion oxidation (HTCO) method, and results were compared with those measured by another laboratory. Concentrations of DOC ranged from 58 to 104 ${\mu}M$ in the upper 200 m, showing a typical decreasing pattern with depth. Generally, concentrations of DOC were relatively lower, with higher nutrient concentrations, in the upper layer of the coastal upwelling zone. Concentrations of DOC ranged from 54 to 64 ${\mu}M$ in the deep Ulleung Basin (200-1500 m), and were higher than those in the Pacific and Atlantic oceans. In association with rapid vertical ventilation of the euphotic, this difference indicates a larger accumulation of semi-labile DOC in the deep East Sea than in the major oceans. A correlation between apparent oxygen utilization (AOU) and DOC in the deep ocean of the East Sea revealed that only a small portion (<10%) of the sinking DOC, relative to the sinking particulate organic carbon (POC), contributes to microbial degradation. Our results present an important data set of DOC in the East Sea, which plays a critical role in carbon cycle modeling and sequestration.

• Journal of the Ergonomics Society of Korea
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• v.18 no.1
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• pp.71-90
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• 1999

This study was conducted to examine the comfortability of wearing pantyhose in summer. To satisfy this purpose. 4 types of pantyhose were chosen from the market: a Mono type(M), a Wooly type(W), and two Support types(Sl, S2), were chosen. After the performances of samples were measured, these were worn by 8 healthy adult women. Under the summer field environment, psychological comfort ability was examined through the 5 steps of SD method. Physiological comfort ability was examined by measuring the body reactions(clothing pressure, skin temperature, total body weight loss, rectal temperature, pulse rates, and blood pressure), under the artificial environment($28.5{\pm}0.5^{\circ}C$, $82{\pm}3%$). The results of this examination were as follows : The order of comfortability which people felt in the field was W>M>S1>S2. The number of items which showed the highest correlation with comfort ability decreased and the correlation was lowered on the whole as time went by. There was positive high correlation between the performances of samples and comfort ability in compressibility, air permeability, water vapor permeability, while a negative high correlation in thickness, weight, compressional resiliency, strain (course) and moisture regain. The mean skin temperature was in the comfort zone, and rectal temperature, pulse rates, blood pressure were mostly in the normal range. Also it was showed that the correlation between the performance of samples and body reactions, except total body weight loss, was low.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2002.11a
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• pp.333-337
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• 2002

All the outdoor and indoor spaces are connected with each other. The human being moves toward those spaces and experiences temperature fluctuation between the natural and artificial temperature. We conducted an experiment which subjects are the college students wearing the data logger in urban life, and measured 24 hours' exposed temperature and thermal comfort in summer. Results were as follows. 1. Most subjects get weather information(84.6％). Fashion(46.2％) and weather (30.8％) are the reasons to select clothes. They spend their time in indoor environment for 84.92％ hours of a day and have an air-conditioner(61.5％) in their houses. 2. Exposed temperature fluctuation were from 33.8$^{\circ}C$ to 15.6$^{\circ}C$. The median value of experienced temperature were 26-27$^{\circ}C$ and average temperature was 26.3$^{\circ}C$. Subjects experienced cold shock of 3.96 times in a day and 67.21％ of all evaluated thermal comfort in the range of -1 and 1 by ASHRAE 7 Category Scales. Artificial environment which connected with outside let people experienced temperature fluctuation in wide range.

• Journal of Environmental Science International
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• v.11 no.10
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• pp.1133-1140
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• 2002

The growth and extent of the local pressure field at any point is of primary importance as it supplies the driving force for the local wind circulation which causes a medium-range transport of air pollutants. The local pressure field is produced by the variation of temperature in the lower layers of the atmosphere, and is called the thermal wave. The thermal wave is influenced by the difference in the diurnal variations between two regions with different surface condition, for example land and sea. This difference produces the land- and sea-breeze phenomenon, and brings corresponding variations in the form of the thermal wave. Daytime temperature over the inland area (Daegu) was higher than that of the coastal area (Busan). The temperature difference reached about 5~6$^{\circ}C$ in the late afternoon(30-31 May 1999). The low pressure system of Daegu was most fully developed at the time. In this study, we investigated the possibility of thermal low onset around Daegu in summer with an analytical model. The topography effect was neglected in the model. We could predict a thermal low-pressure of about 3.4hPa at Daegu with wide flat land surface, when the inland area is about 6K warmer than the coastal area temperature. The pressure decrease is somewhat less than the observed value(4~5 hPa).

• Environmental Engineering Research
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• v.19 no.3
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• pp.223-228
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• 2014

We investigated seasonal algae variability and its influence on water quality in an agricultural reservoir. We observed that maximal total phosphorus (TP) loads were 1,715 kg from farmland in September, which changed the ecosystem in the reservoir. At this time, Dictyosphaerium pulchellum as green algae dominated. Aulacoseira ambigua as diatom became the most dominant from November 2010 to May 2011. The diatom was sensitive to water temperature. Microcystis spp. and Oscillatoria spp. as cyanobacteria were dominant during summer and fall, and sank down to the sediment during winter and spring. Increasing water temperature during summer causes anaerobic conditions in the sediment, leading to regrowth of cyanobacteria. With regard to the ratio of total nitrogen (TN) to TP, green algae and cyanobacteria were dominant at TN:TP ratios less than 20-30. Diatoms were dominant at TN:TP ratios greater than 30-40. Statistical analysis indicated that diatom growth was dependent on water temperature and TN concentration. TP concentration and water temperature were the key factors for the growth of cyanobacteria and green algae. From these results of this study, the management of land-use was an important parameter for improving water quality in the agricultural reservoir.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.90-100
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• 2021

In the north and northeast of Cheonsu Bay, short-term fluctuations of surface water temperature are large owing to shallow water depth, weak current, and freshwater runoff. However, in the south of the bay, water temperature fluctuations are small owing to the inflow of offshore water by tidal currents. The water temperature in the north of the bay is higher in spring and summer than in the south of the bay, but lower in autumn and winter. During spring season, the fluctuation in the northern surface water temperature is the highest. The temperature fluctuations owing to tides are in phase with the tide in autumn and winter, and in the reverse phase with the tide in spring and summer. The dominant periods of water temperature fluctuations are half a day, daily, 15 days, and 1 month owing to the tide and 7 to 10 days, which are estimated based on atmospheric factors. Half a day and daily water temperature fluctuations are also highly correlated with air temperature and wind fluctuations. The sea area where water temperature fluctuations are highly correlated is divided into the north and south of the bay. The fluctuation phase is faster in the north of the bay than in the south or in the center.

• Atmosphere
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• v.30 no.4
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• pp.335-346
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• 2020

Three free parameters included in a cumulus parameterization are optimized by using micro-genetic algorithm for three precipitation cases occurred in the Korea Peninsula during the summer season in order to reduce biases in a regional model associated with the uncertainties of the parameters and thus to improve the predictability of precipitation. The first parameter is the one that determines the threshold in convective trigger condition. The second parameter is the one that determines boundary layer forcing in convective closure. Finally, the third parameter is the one used in calculating conversion parameter determining the fraction of condensate converted to convective precipitation. Optimized parameters reduce the occurrence of convections by suppressing the trigger of convection. The reduced convection occurrence decreases light precipitation but increases heavy precipitation. The sensitivity experiments are conducted to examine the effects of the optimized parameters on the predictability of precipitation. The predictability of precipitation is the best when the three optimized parameters are applied to the parameterization at the same time. The first parameter most dominantly affects the predictability of precipitation. Short-range forecasts for July 2018 are also conducted to statistically assess the precipitation predictability. It is found that the predictability of precipitation is consistently improved with the optimized parameters.

• Journal of People, Plants, and Environment
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• v.24 no.1
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• pp.85-94
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• 2021

Background and objective: This study examined, compared, and analyzed the tree vitality of the trees growing on the artificial ground of Seoullo 7017 that transformed the overpass that was to be demolished into a "sky garden" using portable tree pots. Methods: Based on the summer season when the metabolic activity of plants is most active, this study measured the cambial electrical resistance in four directions(east, west, south and north), using the Shigometer (model OZ-93, Osmose) and compared the location and analysis of pots according to their means and standard errors. Results: Meanwhile, according to the analysis, vitality was relatively superior in pots with a big diameter, trees planted individually than in groups, trees of the ramp section rather than the bridge section, and in the southwest direction of the cambium. Conclusion: This study revealed the improper condition of the planting plan and implementation on the site, where various species of trees are displayed in a poor environment. Despite the significant assessment of the vitality of various trees introduced within Seoullo 7017 for the first time, this study is limited in that the data used were measured only once in summer. In this regard, it raised the need for continuous interest in and monitoring of a special plant environment and development of proper maintenance and management techniques, along with follow-up research on seasonal and temperature conditions, soil moisture and root development conditions to supplement this research.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.11
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• pp.115-120
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• 2021

In this study, cigarettes, which are an essential element in the production of tobacco, are generally not cylindrical. The main materials used for cigarettes are generally hemp and pulp. For the production of cylindrical cigarettes, the cigarettes or cylinders are mounted via gluing. This adhesive is a vinyl acetate emulsion, a high-temperature melt adhesive, and is adhered in a cylindrical shape immediately after being linearly applied to the inner surface of the paper roll or a local part. These adhesives are greatly affected by the atmospheric temperature of the manufacturing space in summer and winter. In the summer, even if the adhesive is temporarily adhered, the coagulation time of the adhesive is long, and problems such as deterioration of the adhesive state occur. in the winter, there is a problem that the temperature of the manufacturing space is low and the adhesive force of the adhesive is poor, resulting in defective adhesive products. In order to solve these problems, another heat transfer device is utilized to cure the remaining adhesive to ensure higher adhesiveness.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.15 no.4
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• pp.362-371
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• 1986

In the normal Refrigeration process, the condensation heat of refrigerant s not been used because of its low-temperature waste heat. To recover the condensation waste heat of R-12 refrigerator, a drying and hot water system was designed and experimented. The results obtained were summarized as follows: 1. As the temperature a temosphere was increased, the temperature of discharge gas of compressor was increased. And the temperature was $80-84^{\circ}C$ for air condensing type and was $68-71^{\circ}C$ for water condensing type during summer. 2. The condensation waste heat could be obtained up to $50-55^{\circ}C$ of drying heat-source and Hot water in summer. In this case, recovered rate was about $73\%$. And the more temperature of drying Heat-source and Hot water were increased, the more a recovered rate were decreased. 3. When comparing drying characteristics of Agro-products in dryer of waste heat utilization and Hot air, there was no quality difference in products. But drying time of the former was 3 Hours longer than the latter. 4. The condensation waste heat of compressor could be applied into the drying of marine products, the predrying of agro-products and making hot water. And showed high possibility of the waste heat using in low-temperature storage.