• ALGAE
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• v.34 no.2
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• pp.111-126
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• 2019

The phototrophic dinoflagellate Biecheleriopsis adriatica is a small suessioid species characterized by a fragile thin wall. Although the morphology of this dinoflagellate is well established, there is currently little information available on its distribution and the environmental factors that influence this distribution. Thus, to investigate the spatial and seasonal distributions of the vegetative cells of B. adriatica in Korean waters, surface water samples were collected on a seasonal basis from 28 stations in the East, West, and South Sea of Korea and Jeju Island from April 2015 to October 2018, and abundances of the vegetative cells of B. adriatica were quantified using quantitative real-time polymerase chain reactions, for which we developed the species-specific primer and probe set. Simultaneously, major environmental parameters, including temperature, salinity, nutrient concentrations, and dissolved oxygen concentrations were measured. The vegetative cells of B. adriatica were detected at 20 of the 28 sampling stations: 19 stations in summer and 6 in autumn, although from no stations in either spring or winter. The ranges of water temperature and salinity at sites where this species was detected were $17.7-26.4^{\circ}C$ and 9.9-34.3, respectively, whereas those of nitrate and phosphate concentrations were not detectable-96.2 and $0.18-2.66{\mu}M$, respectively. Thus, the sites at which this species is found are characterized by a narrow range of temperature, but wide ranges of salinity and concentrations of nitrate and phosphate. The highest abundance of the vegetative cells of B. adriatica was $41.7cells\;mL^{-1}$, which was recorded in Jinhae Bay in July 2018. In Jinhae Bay, the abundance of vegetative cells was significantly positively correlated with the concentration of nitrate, but was negatively correlated with salinity. On the basis of these findings, it appears that the abundance of B. adriatica vegetative cells shows strong seasonality, and in Jinhae Bay, could be affected by the concentrations of nitrate.

• Journal of Environmental Impact Assessment
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• v.30 no.3
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• pp.164-174
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• 2021

Information on biodiversity plays an important role in conservation planning for ecosystem. As existing biodiversity indices are calculated and predicted only based on the number of individuals and species, it is difficult to explain aspects of genetic and ecological diversity. Phylogenetic diversity can indirectly evaluate ecological diversity as well as genetic diversity overlooked by existing biodiversity assessments. In this study, typical metrics of biodiversity (e.g., species diversity, species richness, etc.) and phylogenetic diversity were evaluated together using a long-term monitoring data of winter birds in Jungrang, Cheonggye and Anyang stream where are designated as Seoul migratory bird reserves. Then discussed the meaning of each assessmentresult. In Jungrang and Anyang stream, the number of individuals generally decreased overtime, whereas in Cheonggye stream, there was no significant change. In addition, species abundance increased over time slightly in Cheonggye stream, while there was no significant change in Jungrang and Anyang stream. Species diversity temporally increased in Jungrang and Cheonggye stream, excluding Anyang stream, but phylogenetic diversity showed a tendency to increase only in Cheonggye stream. These changes in the biodiversity assessment indices are thought to be due to anthropogenic disturbances such as construction that occurred within each site, and it was shown that species diversity and phylogenetic diversity do not always lead to the same assessment results. Therefore, this study suggests that biodiversity assessment needs to be considered from various contexts such as genetic and ecological perspectives.

• Journal of the Korean Society of Food Culture
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• v.34 no.5
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• pp.495-507
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• 2019

This study investigates the Gabo Jaedong Jemuljeongnyechaek, which is the recording of the darye executed over a period of a year in 1834 ($34^{th}$ year of reign by King Sunjo) in the latter part of the Joseon Dynasty, two years after the death of Princess Bokon, the $2^{nd}$ daughter of King Sunjo. Accordingly, we examined the types of darye (tea ceremonies) and the characteristics of the composition of foods at ancestral rites of the royal families of Joseon. Moreover, we also analyzed the cooking methods and characteristics of food terminologies used in the darye. This includes 39 categories of food and ingredients used for tea ceremonies held for one year, on behalf of the deceased Princess Bokon in 1834. The darye for the monthly national holiday was held along with the darye on the $1^{st}$ and the $15^{th}$ day of every month. The darye for rising up and the birthday darye were held on May $12^{th}$ and October $26^{th}$ of the lunar calendar, being the anniversaries of the death and the birth of Princess Bokon, respectively. The birthday darye and the darye for New Year's Day, Hansik ($105^{th}$ day after winter solstice), Dano ($5^{th}$ day of the $5^{th}$ month of the lunar calendar), and Thanksgiving "Chuseok" were held in the palace and at the burial site of the Princess. During the darye for rising up in May and the Thanksgiving darye at the burial site in August, rituals offering meals to the deceased were also performed. The birthday darye at the burial site of Princess Bokon featured the most extensive range of foods offered, with a total of 33 dishes. Foods ranging 13~25 dishes were offered at the national holiday darye, while the darye on the $1^{st}$ and the $15^{th}$ of the month included 9~11 food preparations, making them more simplified with respect to the composition of foods offered at the ceremony, in comparison to the national holiday darye. The dishes were composed of ddeok, jogwa, silgea, hwachae, foods such as tang, jeok, jjim, hoe, and sikhae, and grain-based foods such as myeon, mandu, and juk. Foods offered at the burial site darye included 12~13 dishes comprising ban, tang, jochi, namul, chimchae, and jang. Meals offered at the darye had a composition similar to that of the daily royal table (sura). Darye recorded in the Jemuljeongnyechaek displayed characteristics of the seasonal foods of Korea. Jemuljeongnyechaek has detailed recordings of the materials, quantities, and prices of the materials required for preparations of the darye. It is quite certain that Jemuljeongnyechaek would have functioned as an essential reference in the process of purchasing and preparing the food materials for the darye, that were repeated quite frequently at the time.

• 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.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.6_2
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• pp.1067-1074
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• 2020

Green houses provide a more conditioned and warmer environment than the outside environment due to insulation. Currently used insulation materials include soft film (PVC, PE, EVA), foamed PE sheet, non-woven fabric, reflective film, and multi-layer insulation curtain, but there are many disadvantages and to compensate for this, silica aerogel insulation material with excellent warmth, light weight, and small volume Research using is in progress. In this study, the temperature change of the quadruple-structure green house and the temperature change in the dual-structure green house of soft film and silica airgel were investigated. The daytime temperature change was highest in A and A2 (soft film) at 10 to 16:00 after sunrise, but showed the lowest temperature at 17 to 18:00, which is the sunset time, showing the greatest change. The airgels of D and D2 showed the smallest change in temperature after sunrise and right after sunset. That is, it can be said that the airgel is hardly affected by external temperature. The temperature change at night was highest in D and D2 (aerogel) for both quadruple and dual structures. The temperature at night was measured higher in the quadruple structure than in the double structure. As for the ratio of the internal temperature to the external temperature for the quadruple structure and the double structure, D (aerogel) was not affected by the external temperature during the day in the quadruple structure and the double structure. D (Aerogel) seems to be able to reduce the damage caused by high temperatures in summer due to the high thermal insulation effect of the airgel, as the temperature rises above 4℃ at night. And in winter, it helps to save heating costs due to less heat emitted to the outside.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.3
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• pp.305-316
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• 2021

Construction accidents occur due to a number of reasons-worker carelessness, non-adoption of safety equipment, and failure to comply with safety rules are some examples. Because much construction work is done outdoors, weather conditions can also be a factor in accidents. Past construction accident data are useful for accident prevention, but since construction accident data are often in a text format consisting of natural language, extracting construction hazards from construction accident data can take a lot of time and that entails extra cost. Therefore, in this study, we extracted construction hazards from 2,026 domestic construction accident reports using text mining and performed a seasonal analysis of construction hazards through frequency analysis and centrality analysis. Of the 254 construction hazards defined by Korea's Ministry of Land, Infrastructure, and Transport, we extracted 51 risk factors from the construction accident data. The results showed that a significant hazard was "Formwork" in spring and autumn, "Scaffold" in summer, and "Crane" in winter. The proposed method would enable construction safety managers to prepare better safety measures against outdoor construction accidents according to weather, season, and climate.

• Environmental and Resource Economics Review
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• v.30 no.4
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• pp.627-648
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• 2021

The fine-dust season management system refers to the policy of implementing enhanced reduction measures in transportation, power, business and living sectors in winter, when fine dust levels are high. The fine dust season management system is a regulatory policy that causes social costs and transfers to various economic players. Equity is an important issue for the cost burden. Therefore, in this study, the cost of each power generator was analyzed using the coal power generation reduction amount of each power generator to verify that the cost of the power sector is evenly distributed. In particular, the effect of the fine dust season management system on coal power generation of power generators was analyzed by applying a synthetic control method that can identify the time-variable effect of the policy. It was confirmed that the fine dust season management system reduced volume of fuel and power generation in coal power plants, resulting in an increase in the cost of the power generation sector, even considering the effect of some power demand due to the COVID-19 crisis. However, it could be seen that these costs were not distributed equally among the generators, and that they were more costly to the specific generators.Social costs incurred by fine dust season management need to be improved so that stakeholders are equally burdened.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.2
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• pp.1-17
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• 2022

This study analyzed the PM_2.5 pattern by using data measured for one year from June 2020 to May 2021 by 21 low-cost sensors installed near the Changwon National Industrial Complex in Changwon, Gyeongsangnam-do. For the PM_2.5 pattern, the land use types around the measuring points and meteorological factors such as air temperature and wind speed were considered. The PM_2.5 concentration was high from November to March in winter, and from 1 to 9 in the morning and early in the morning by time zone. The concentration of PM_2.5 was higher as it got closer to the industrial area, but the concentration was lower in the residential area and public facility area. In terms of meteorological factors, the higher the air temperature and wind speed, the lower the concentration of PM_2.5. As a result of this study, it was possible to identify the PM_2.5 patter near Changwon National Industrial Complex. This result will be useful data that can be used in urban and environmental planning to improve air quality including PM_2.5 in urban area in the future.

• Journal of Korea Water Resources Association
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• v.54 no.7
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• pp.523-534
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• 2021

Meteorological drought originates from a precipitation deficiency and propagates to agricultural and hydrological droughts through the hydrological cycle. Comparing with the meteorological drought, agricultural and hydrological droughts have more direct impacts on human society. Thus, understanding how meteorological drought evolves to agricultural and hydrological droughts is necessary for efficient drought preparedness and response. In this study, meteorological and hydrological droughts were defined based on the observed precipitation and the synthesized streamflow by the land surface model. The Bayesian network model was applied for probabilistic analysis of the propagation relationship between meteorological and hydrological droughts. The copula function was used to estimate the joint probability in the Bayesian network. The results indicated that the propagation probabilities from the moderate and extreme meteorological droughts were ranged from 0.41 to 0.63 and from 0.83 to 0.98, respectively. In addition, the propagation probabilities were highest in autumn (0.71 ~ 0.89) and lowest in winter (0.41 ~ 0.62). The propagation probability increases as the meteorological drought evolved from summer to autumn, and the severe hydrological drought could be prevented by appropriate mitigation during that time.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.234-243
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• 2022

In Korea, hail damage occurs every year, and in the case of agriculture, it causes severe field crop and cultivation facility losses. Therefore, it is necessary to develop a hail information service system customized for Korea's primary production and crop-growing areas to minimize hail damage. However, the observation of hail is relatively more difficult than that of other meteorological variables, and the available data are also spatially and temporally variable. A hail information service system was developed to understand the temporal and spatial distribution of hail occurrence. As part of this, a hail observation database was established that integrated the observation data from Korea Meteorological Administration with the information from newspaper reports. Furthermore, a hail risk map was produced based on this database. The risk map presented the nationwide distribution and characteristics of hail showers from 1970 to 2018, and the northeastern region of South Korea was found to be relatively dangerous. Overall, hail occurred nationwide, especially in the northeast and some inland areas (Gangwon, Gyeongbuk, and Chungbuk province) and in winter, mainly on the north coast and some inland areas as graupel (small and soft hail). Analyzing the time of day, frequency, and hailstone size of hail shower occurrences by region revealed that the incidence of large hail stones (e.g., 10 cm at Damyang-gun) has increased in recent years and that showers occurred mainly in the afternoon when the updraft was well formed. By integrating multidisciplinary data, the temporal and spatial gap in hail data could be supplemented. The hail risk map produced in this study will be helpful for the selection of suitable crops and growth management strategies under the changing climate conditions.