• Journal of Korean Society for Atmospheric Environment
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• v.33 no.2
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• pp.124-138
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• 2017

Physico-chemical measurement of non-refractory submicron particles($NR-PM_1$) was conducted in Baengnyeong Island, Korea using Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) from 2012 to 2014. Organics and ammoniated sulfate were dominant species in $NR-PM_1$. The organics was found to have similar fractions(approximate 40%) of $NR-PM_1$ during the summer and winter, while the sulfate fractions of $NR-PM_1$ were calculated to be approximately 47% and 31% for the summer and winter, respectively, suggesting the possibility that particles provide non-acidic surfaces for condensation of nitric acid in the winter. The nitrate fractions of approximate 4% and 20% of $NR-PM_1$ were observed in August (summer) and November (winter), respectively, resulting that the relatively low concentration of sulfate in $NR-PM_1$ provided a non-acidic surface for nitric acid condensation and formation of particulate ammoniated nitrate is favored thermodynamically in winter. The new particle formation (NPF) event and particle growth rate were analyzed for each month in 2014 using Scanning Mobility Particle Sizer(SMPS). The Percent of NPF events was the highest in winter, but NPF event was not observed during summer due to relatively high temperature and frequent rainfall. The average particle growth rate was 3.5 nm/h and the highest particle growth rate was 5.5 nm/h in May. We observed the long-range transport of the anthropogenic sulfate from the East Asia during the intensive monitoring period of November between Qingdao and Baengnyeong Island in 2013. The relatively high concentrations of m/z 60 measured in HR-ToF-AMS was observed in May and June at Baengnyeong Island, suggesting the possibility of the influence of biomass burning from the East Asia to the Korean Peninsula.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.177-183
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• 2006

The summer production of sweet pepper in Korea which cultured in the highland area such as Hapchon is essential for a year-round export, but has the problem, fruits lose easily those marketability. This study was carried out to find changes of fruit quality in response to storage on sweet pepper cultivars in summer. Seven cultivars of sweet peppers, 'Jubilee', 'Plenty', 'Goal', 'Romeca', 'Derby', 'Midas' and 'Maximalia' were obtained iron growers in Hapchon which was highland of 600-800m from sea level and stored at $10^{\circ}C$ with box packing. Fruit quality was evaluated every 4days up to 4weeks. The weight loss of 'Jubilee' was the lowest, that of 'Romeca' was the highest. The firmness of 'Goal' was maintained highly for 4weeks and the red cultivars was higher than those of other color cultivars. The lightness of 'Jubilee' was sensitively affected by storage duration. Seeds of 'Plenty' and 'Derby' were plentifully browned after 4weeks storage. The occurrence of fruit rotting was after 16-204ay storage and those of 'Plenty' and 'Maximalia' were the earliest. The marketability of 'Jubilee' and 'Romeca' maintained by 70% for 16 days was the highest, but most cultivars lost those by 20% after 24days storage. It may be suggested that the marketability of sweet pepper producted in summer can be stored at $10^{\circ}C$ for 2weeks to maintain that of 80%.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.359-367
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• 2010

The objective of this study was to find optimal planting season of the effect of vegetation competition around planting tree. This study evaluates the possibility of extending the planting period of containerized seedling of Pinus densiflora (1-0 year). We planted seedling at three different seasons (spring, summer, fall) at 18 plots in 3 locations. Planting sites were composed of vigorous vegetation (Site A) and less vigorous vegetation (Site B). For over 3 years, the study investigated survival rate, growth of root collar diameter and height, and biomass of containerized seedling of P. densiflora. In all sites, containerized seedling of P. densiflora showed high survival rate in summer planting. Height and root collar diameter of containerized seedling of P. densiflora were the highest in summer planting, but in the initial period after planting growth was not good. After time passed, growth rate was increased. Site B showed better growth than Site A. Biomass was the highest in summer planting and also the highest in Site B. These results suggest that planting period can be extended by using containerized seedling and vegetation control in the initial is very important for survival and growth of containerized seedling.

• Economic and Environmental Geology
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• v.42 no.1
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• pp.73-84
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• 2009

The stone Buddha and Shrine of Unjusa temple (Korean Treasure No. 797) at Hwasun formed in Koryo Dynasty is unique style which faces each other the back parts of south and north within the stone Shrine. The stone Buddha and Shrine is highly evaluated in historical, artistic and academic respects. But, the stone properties have been exposed in the open system various aspects of degradations weathered for a long time without specific protective facilities. To inquire into relative deterioration and environmental factor, air temperature and relative humidity of the stone Buddha and Shrine were monitored for a year of the indoor and outdoor, respectively. As a result, the temperature shows increase and decrease according to the seasons in the tendency to clear. While the relative humidity is high to keep all four seasons. Highly relative humidity environment induces dew condensation on the interior of stone Buddha and Shrine. The dew condensation is recorded at the spring, summer and winter season. The summer season is double the total of spring and winter season. In the case of summer, dew condensation is long time continued due to high temperature and relative humidity that is kept by more than nearly 100%. There is progress towards chemical weathering throughout dissolve rock properties and alteration on the rock surface. In the case of winter, dew condensation is not kept for a long time as summer. In the winter, which showing a below zero may add physical weathering throughout moisture that happen by dew condensation to repeat freezing and thawing. Therefore, the reduction plan of the relative humidity effect on dew condensation should be prepared.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.422-430
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• 2016

We investigated the abundance and composition of the zooplankton community around Dokdo in the East Sea from 2006 to 2015. Zooplankton samples were collected in the surface mixed layer by vertical hauls using a standard type net at the monitoring stations. There were no clear long-term trends in the average temperature and salinity, but relatively low salinity was recorded in the summer of 2013 and 2015. The average abundances of zooplankton in the summer increased by two orders of magnitude from $317inds./m^3$ in 2008 to $10,242inds./m^3$ in 2015. This long-term increase was accompanied by a slight increase in the chlorophyll-a concentration and a decrease in the catch of potential crucial predators (anchovy, mackerel pike, squid, herring and horse mackerel) in the study area. The dominant zooplankton, accounting for most of the long-term increase, consisted of appendicularian (Oikopleura spp.), which showed a steady increase since 2012, summer species such as Noctiluca scintillans and the cladoceran Penilia avirostris, which showed an abrupt increase, and the copepod Paracalanus parvus s.l., which showed a rapid increase after its first occurrence in summer 2010. These results suggest that the long-term increase of zooplankton could be related to the increase in the concentration of prey and the decrease in the predation pressure of potential predators around Dokdo in the study area.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.287-294
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• 2009

This study conducted to evaluate the growth characteristics of creeping bentgrass in summer after application of the plant growth regulator, Trinecapac-ethyl, and these data may provide basic information to golf course turf maintenance. The results showed that the shoot density of creeping bentgrass was increased an average density of 1.7 $ea/cm^2$ with the trinexapac-ethyl application, especially about 2 $ea/cm^2$ during the growth retarded period of June and July. The root length increased also in June and August. The visual quality was improved significantly with trinexapac-ethyl treatment all the experimental periods, moreover, the effect was significant by reducing a summer decline stress of creeping bentgrass during the warm and humid period of summer. The green speed was significantly improved by this growth regulator treatment and those effect was prominent during stressed season of late June to mid July. Overall of the result, we found that shoot density, visual quality and green speed of bentgrass green were improved by trinexapac-ethyl treated from early growing season of spring and these effects were continued during summer. It should be very beneficial to manage the bentgrass green in stressed season. In future, the possibility and efficiency of mixture with fungicides and/or fertilizers might be needed. The spring green-up test with trinexapac-ethyl will be followed in next spring.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.902-908
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• 2017

To determine the horizontal and temporal distribution of firefly squid, Watasenia scintillans (W. scintillans), larvae, we conducted surveys using IKMT (mesh size: $500{\mu}m$) and CTD (SBE9plus) with Fisheries Research Vessel (FRV, TAMGU 21) in the southern part of the East Sea in summer (August) and autumn (September and November) 2015. A total of 238 larvae, ranging in mantle length (ML) from 0.6 mm to 18.5 mm, were collected at 28 stations. Abundance and larval distribution density were significantly higher in summer than in autumn during the study period. Especially, the highest density of W. scintillans was observed in the coastal waters of the East Sea from Pohang to Pyunghae where cold water masses were distributed in summer. Optimum embryo survival temperature ($6-16^{\circ}C$) 40 to 180 m depth ranges for stations which larvae were collected.

• Korean Journal of Environment and Ecology
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• v.36 no.4
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• pp.402-412
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• 2022

This study investigated each forest's stand characteristics and the NVOCs emission characteristics for Quercus acuta, Castanopsis sieboldii, Dendropanax trifidus, Camellia Japonica which are major warm temperate evergreen broad-leaved species, and Pinus thunbergii. Data were collected from May 2019 to January 2020. The seasonal temperature and humidity of each research site indicated the typical climatic characteristics of Korea, which are hot and humid in summer and cold and dry in winter. Also, the atmospheric pressure was generally high in winter and higher in autumn and winter than in spring and summer. Overall, the total volume of NVOCs (Natural Volatile Organic Compounds) from the five research sites was the highest in the summer. The concentration of TNVOCs was relatively high in the Dendropanax trifidus forest in spring and winter, the Castanopsis sieboldii forest in the autumn, and the Quercus acuta forest in the summer. According to the results of this study, it was confirmed that the concentrations of NVOCs emission of warm temperate evergreen broad-leaved species such as Quercus acuta, Castanopsis sieboldii, Dendropanax trifidus and Camellia Japonica were not lower but rather higher than Pinus thunbergii. The correlation was positive (+) between NVOCs emission and temperature (r=0.590, P=0.000) or humidity (r=0.655, P=0.000), whereas it was negative (-) between NVOCs emission and atmospheric pressure (r=-0.384, P=0.000) or wind speed (r=-0.263, P=0.018). Among the micrometeological factors, humidity (β=0.507, P=0.000) was found to have the greatest effect on NVOC emission, followed by temperature, atmospheric pressure, and wind speed.

• KIEAE Journal
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• v.15 no.6
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• pp.101-109
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• 2015

Purpose: Glazing and shading devices influence a lot on the thermal and visual environment in office buildings. Solar heat and daylight are contrary concept, therefore proper arrangement of thermal and optical performance is needed when designing a glazing and shading devices. The purpose of this study is to examine the conditions of the glazing and shading devices available for promoting the reduction of cooling loads + lighting loads and the improvement in thermal comfort and visual comfort for the summer season in an office building installed with venetian blind. Method: This study established 12 simulation cases which have different glazings and the positions of venetian blind for evaluating different thermal and optical performance. And by using EnergyPlus v8.1 and Window v7.2 program, we quantitatively analyzed cooling loads + lighting loads, thermal comfort and visual comfort in an office building installed with the glazing and shading devices. Result: Consequently, Case 9(Double Low-E+Exterior Blind) is the best arrangement of solar heat gain and daylight influx, thereby becomes the most excellent case of reducing cooling+lighting loads(46.8%) and simultaneously becomes the enhancement case in thermal comfort. Also, DGI(Daylight glare index) under clear sky conditions in summer was evaluated to be 19.6, and thereby satisfied the recommendation level of allowing visual comfort.

• Journal of Ocean Engineering and Technology
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• v.22 no.5
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• pp.7-24
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• 2008

Masan-Jinhae Bay, in Korea, is known for its frequent algal bloom outbreaks. This study was conducted in order to examine the environmental characteristics of the area, with the aim of identifying indicators that could be used to speculate about future algal blooms. The water temperatures and salinities in Haengam Bay, one of the small inner bays within Jinhae, appeared to re relatively higher than those in Masan and Jinhae bays, across most seasons. Furthermore, stratification begins to develop in all three regions from spring to summer as a result of the local heating effects and an increase in the efficient from the surrounding land. As a result, anoxic conditions appear near the bottom layer of the bay, leading to the deterioration of water quality, which has been identified as one of the causes of bloom outbreaks. Compared to Haengam and Jinhae bays, concentrations of DIN and DIP were remarkably higher in Masan Bay. However, the mean ratio of DIN to DIP was 3.3$\sim$13.6 in all three regions throughout the year, suggesting that nitrogen can function as a growth-limiting factor for phytoplankton. The results of mathematical models showed that cumulative organic pollutants may be a trigger for direct algal bloom occurrences, since residual tidal currents appeared to be less than $3\;cm\;\cdot\;s^{-1}$. Furthermore, computed DO concentrations in the four small inner bays of Jinhae during the summer appeared to be $3\;cm\;\cdot\;l^{-1}$ indicating a hypoxic state. Likewise, computed Chl-a concentrations turned out to be more than $0.01\;mg\;\cdot\;l^{-1}$, indicating eutrophication across most seasons. Based on the overall results, Masan-Jinhae Bay appeared to possess a very high potential for algal bloom outbreaks at anytime during the year.