• Journal of Wetlands Research
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• v.23 no.4
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• pp.317-326
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• 2021

The present study was carried out with a view to understand the distribution and ecology of Clihton retropictus (Martens, 1879), a class II endangered wildlife designated and protected by the Ministry of Environment, Republic of Korea, and to suggest the effective conservation and management measures for this species and its habit. First, the distribution of Clihton retropictus was investigated nationwide, and environmental factors such as salinity and substratum were analyzed in consideration of the ecological characteristics of this species. In addition, the individual size, density, and movement of Clihton retropictus per each district surveyed were analyzed. Due to its nature of inhabiting in the brackish water zone, the analysis showed that the salinity of this species was 0.7 ~ 16.6‰ at low tide and 1.0 ~ 17.3% at high tide. It was learned from the analysis of substratum that its composition in each river under investigation was slightly different, but most of substratum had a higher composition ratio than gravel (pebble, 16 ~ 64 mm). On the other hand, the size of each individual was checked by measuring the length of its diameter, and there was almost no change in the individual when the inhabited range of Clihton retropictus was short. However, there was tendency that the longer the habitat range, the bigger the individual size. From surveying the population density by season, it was made clear that, during the summer (July to August) and fall (September to October), the density was relatively higher while the number of individuals decreased significantly during winter (November to December) when the water temperature was lowered. In an effort to effectively establish conservation and management measures, the moving distance was measured, and it became known that, during the surveys in summer and fall when the individuals were active, the individuals moved in more distances than during the winter survey. The results of this study are expected to be utilized as basic data for establishing effective management plans such as creation of habitats for Clihton retropictus, its migration projects and selection of migration destinations which get unavoidable due to development projects.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.731-738
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• 2021

This study investigated the physicochemical properties of rice starch isolated from broken rice using alkaline steeping (AKL) and enzymatic digestion (ENZ) methods. Broken rice starch (BRS) by AKL and ENZ possessed crude protein contents (0.6-1.4%) acceptable to commercial products of native starch and belonged to an intermediate amylose rice starch. AKL-BRS and ENZ-BRS showed a typical A-type crystal packing arrangement with small variations in their relative crystallinity. ENZ-BRS exhibited higher gelatinization onset and peak temperatures, and a narrower gelatinization temperature range than AKL-BRS, indicating that annealing occurred in ENZ-BRS. Lower swelling power and solubility were generally observed in the ENZ-BRS. ENZ-BRS also showed slower viscosity development, higher peak and trough viscosities, and lower breakdown, final, and setback viscosities, compared to those in AKL-BRS. These results are ascribed to the annealing phenomenon in ENZ-BRS. Overall, BRS from cheap broken rice using AKL and ENZ could contribute to the expansion of rice starch utilization in food and non-food industries.

• Journal of the Korean earth science society
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• v.42 no.5
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• pp.479-495
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• 2021

This study investigates the synoptic (patterns of southern highs, northern lows, and lows rapidly developed by tropopause folding), thermodynamic, and kinematic characteristics of a strong wind that occurred in the Yeongdong region of South Korea on March 18-20, 2020. To do so, we analyzed data from an automatic weather station (AWS), weather charts, the European Centre for Medium-range Weather Forecasts (ECMWF) reanalysis, rawinsonde, and windprofiler radars. The daily maximum instantaneous wind speed, exceeding 20 m s^-1, was observed at five weather stations during the analysis period. The strongest instantaneous wind speed (27.7 m s^-1) appeared in the Daegwallyeong area. According to the analysis of weather charts, along with the arrangement of the north-south low-pressure line, the isobars were moved to the Yeongdong area. It showed a sine wave shape, and a strong wind developed owing to the strong pressure gradient. On March 19, in the northern part of the Korean Peninsula, with a drop in atmospheric pressure of 19 hPa or more within one day, a continuous strong wind was developed by the synoptic structure of the developing polar low. In the adiabatic chart observed in Bukgangneung, the altitude of the inversion layer was located at an altitude of approximately 1-3 km above the mountaintop, along with the maximum wind speed. We confirmed that this is consistent with the results of the vertical wind field analysis of the rawinsonde and windprofiler data. In particular, based on the thermodynamic and kinematic vertical analyses, we suggest that strong winds due to the vertical gradient of potential temperature in the lower layer and the development of potential vorticity due to tropopause folding play a significant role in the occurrence of strong winds in the Yeongdong region.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.51-60
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• 2021

Modern society is becoming more informed and intelligent with the development of digital technology, in which humans, objects, and networks relate with each other. In accordance with the changing times, a garden system has emerged that makes it easy to supply the ideal temperature, humidity, sunlight, and moisture conditions to grow plants. Therefore, this study attempted to grasp the concept, perception, and trends of smart gardens, a recent concept. To achieve the purpose of this study, previous studies and text mining were used, and the results are as follows. First, the core characteristics of smart gardens are new gardens in which IoT technology and gardening techniques are fused in indoor and outdoor spaces due to technological developments and changes in people's lifestyles. As technology advances and the importance of the environment increases, smart gardens are becoming a reality due to the need for living spaces where humans and nature can co-exist. With the advent of smart gardens, it will be possible to contribute to gardens' vitalization to deal with changes in garden-related industries and people's lifestyles. Second, in current research related to smart gardens and users' experiences, the technical aspects of smart gardens are the most interesting. People value smart garden functions and technical aspects that enable a safe, comfortable, and convenient life, and subjective uses are emerging depending on individual tastes and the comfort with digital devices. Third, looking at the usage behavior of smart gardens, they are mainly used in indoor spaces, with edible plants are being grown. Due to the growing importance of the environment and concerns about climate change and a possible food crisis, the tendency is to prefer the cultivation of plants related to food, but the expansion of garden functions can satisfying users' needs with various technologies that allow for the growing of flowers. In addition, as users feel the shapes of smart gardens are new and sophisticated, it can be seen that design is an essential factor that helps to satisfy users. Currently, smart gardens are developing in terms of technology. However, the main components of the smart garden are the combination of humans, nature, and technology rather than focusing on growing plants conveniently by simply connecting potted plants and smart devices. It strengthens connectivity with various city services and smart homes. Smart gardens interact with the landscape of the architect's ideas rather than reproducing nature through science and technology. Therefore, it is necessary to have a design that considers the functions of the garden and the needs of users. In addition, by providing citizens indoor and urban parks and public facilities, it is possible to share the functions of communication and gardening among generations targeting those who do not enjoy 'smart' services due to age and bridge the digital device and information gap. Smart gardens have potential as a new landscaping space.

• Korean Journal of Breeding Science
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• v.43 no.1
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• pp.68-80
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• 2011

This study was conducted to investigate characteristics and variations of rice panicle traits for breeding temperate japonica varieties adapted to tropical environment. Eleven panicle traits were investigated from nine Korean rice varieties cultivated in Korea and wet season of the Philippines. Tested cultivars were composed of six temperate japonica varieties, three Tongil-type varieties, and one indica variety bred in the Philippines. The number of spikelets on secondary rachis branches (SRBs) was the most variable trait in both environments, while the mean number of spikelets on a primary rachis branch (PRB) was the least variable. Compared with PRB-related traits, SRB traits showed higher correlation with the number of spikelets per panicle. Compared with the plants grown in Korea, the number of spikelets on SRBs, the number of SRBs, spikelets, and rachis branches per panicle were decreased more than other traits in the Philippines. According to path analysis, the number of spikelets on SRBs per panicle affects the number of spikelets per panicle more than the number of spikelets on PRBs per panicle. Climatic factors such as growth duration, cumulative mean temperature, and integrated solar radiation were highly correlated with the relative rate of number of spikelets per panicle. To breed temperate japonica rice varieties adapted to tropical environment, it would be important to select lines which maintain proper growth duration and spikelets on SRBs in target region.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.632-637
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• 2010

'Hanseol' is a new very early-maturing, cold tolerant and high quality japonica rice variety developed from a cross of 'Jinbu24' and 'Jinbu25' by the rice breeding team of National Institute of Crop Science (NICS), Rural Development Administration (RDA) in 2009. The heading date of this variety is July 25, which is four days earlier than check variety, 'Jinbubyeo'. 'Hanseol' has 65 cm of culm length, 99 spikelets per panicle, 82.9% of ripened grain rate, and 21.5 g of 1,000 grain-weight of brown rice. This variety shows susceptibility to bacterial leaf blight and virus diseases, and insect pests. It is tolerant to cold stress in terms of less heading delay and high fertility in cold water irrigated cultivation. This variety shows delayed leaf senescence and considerable tolerance to viviparous germination at ripening stage. The milled rice of this variety exhibits translucent, clear non-glutinous endosperm and medium-short grain. 'Hanseol' showed low gelatinization temperature and 6.1% protein content, 19.1% amylose content and good palatability of cooked rice. The milled rice yield of this variety is about 5.43 MT/ha at ordinary culture in local adaptability test for three years. 'Hanseol' would be highly adaptable to mid-north and mid-mountainous areas, and mid-northern alpine area in Korea.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.153-158
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• 2008

"Baegjoong", a white winter wheat (Triticum aestivum L.) cultivar was developed by the National Institute of Crop Science, RDA. It was derived from the cross "Keumkang"/"Olgeuru" during 1996. "Baegjoong" was evaluated as "Iksan307" in Advanced Yield Trial Test in 2004. It was tested in the regional yield trial test between 2005 and 2007. "Baegjoong" is an awned, semi-dwarf and soft white winter wheat, similar to "Keumkang" (check cultivar). The heading and maturing date of "Baegjoong" were similar to "Keumkang". Culm and spike length of "Baegjoong" were 77 cm and 7.5 cm, similar to "Keumkang". "Baegjoong" had lower test weight (802 g) and lower 1,000-grain weight (39.8 g) than "Keumkang" (811 g and 44.0 g, respectively). It had resistance to winter hardiness, wet-soil tolerance and lodging tolerance. "Baegjoong" showed moderate to pre-harvest sprouting (23.9%) although "Keumkang" is susceptible to pre-harvest sprouting (38.9%). "Baegjoong" had similar flour yield (72.4%) and ash content (0.41%) to "Keumkang" (72.0% and 0.41%, respectively) and similar flour color to "Keumkang". It showed lower protein content (8.8%) and SDS-sedimentation volume (35.3 ml) and shorter mixograph mixing time (3.8 min) than "Keumkang" (11.0%, 59.7 ml and 4.5 min, respectively). Amylose content and pasting properties of "Baegjoong" were similar to "Keumkang". "Baegjoong" had softer and more elastic texture of cooked noodles than "Keumkang". Average yield of "Baegjoong" in the regional adaptation yield trial was $5.88\;MT\;ha^{-1}$ in upland and 5.35 MT ha-1 in paddy field, which was 13% and 17% higher than those of "Keumkang" ($5.21\;MT\;ha^{-1}$ and $4.58\;MT\;ha^{-1}$, respectively). "Baegjoong" would be suitable for the area above the daily minimum temperature of $-10^{\circ}C$ in January in Korean peninsula.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.627-631
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• 2010

A new cultivar of lettuce (Lactuca sativa L.) with wrinkled traverse elliptic and deep red leaf, 'Chunpungjeokchukmyeon' which has late bolting and deep red expression leaf color was developed from a cross between 'Pojabijeokchukmyeon' (red leaf color and late bolting) and 'Meokchima' (Deep red and low yield). The cross and selection for advanced lines had been done by the pedigree method during 2000-2007. The advanced lines were evaluated for yield and adaptability at several locations in Korea (Gangwon-do, Gyeonggi-do, Chungcheongbuk-do, Jeollabuk-do, Gyeongnam-do, and Jeju-do) from 2008 to 2009. The 'Chunpungjeokchukmyeon' has gray seed color and traverse elliptic leaves. The type of matured stage is medium shape between 'chukmyeon' and 'chima' leaf lettuce. Compared to 'Dukseomjeokchukmyeon', marketable yield of 'Chunpungjeokchukmyeon' was higher by 6% (at 372 g per plant) and 'Chunpungjeokchukmyeon' has particularly improved expression of deep red leaf color in high temperature cultivation in the field. The shelf-life of 'Chunpungjeokchukmyeon' was three weeks longer than 'Dukseomjeokchukmyeon' at 4$^{\circ}C$. The anthocyanin content of 'Chunpungjeokchukmyeon' was higher than that of 'Dukseomjeokchukmyeon' with 17.5 mg/100g. The BSL (latucin+8-deoxylactucin+lactucopicrin) content of 'Chunpungjeokchukmyeon' is lower than that of 'Dukseomjeokchukmyeon'. Furthermore, its taste is better, more crispy, and sweeter than those of 'Dukseomjeokchukmyeon'. So we recommend that new cultivar 'Chunpungjeokchukmyeon' can be suitable for cultivation in spring season than summer season.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.210-218
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• 2018

Background: Soil respiration (Rs) is a major factor of the absorption and accumulation of carbon through photosynthesis in the ecosystem carbon cycle. This directly affects the amount of net ecosystem productivity, which affects the stability and sustainability of the ecosystem. Understanding the characteristics of Rs is indispensable to scientifically understand the carbon cycle of ecosystems. It is very important to study Rs characteristics through analysis of environmental factors closely related to Rs. Rs is affected by various environmental factors, such as temperature, precipitation, soil moisture, litter supply, organic matter content, dominant plant species, and soil disturbance. This study was conducted to analyze the effects of micro-topographical differences on Rs in forest vegetation by measuring the Rs on the ridge and southern slope sites of the broadly established Quercus mongolica forest in the central Korean area. Method: Rs, Ts, and soil moisture data were collected at the southern slope and ridge of the Q. mongolica forest in the Mt. Jeombong area in order to investigate the effects of topographical differences on Rs. Rs was collected by the closed chamber method, and data collection was performed from May 2011 to October 2013, except Winter seasons from November to April or May. For collecting the raw data of Rs in the field, acrylic collars were placed at the ridge and southern slope of the forest. The accumulated surface litter and the soil organic matter content (SOMC) were measured to a 5 cm depth. Based on these data, the Rs characteristics of the slope and ridge were analyzed. Results: Rs showed a distinct seasonal variation pattern in both the ridge and southern slope sites. In addition, Rs showed a distinct seasonal variation with high and low Ts changes. The average Rs measurements for the two sites, except for the Winter periods that were not measured, were $550.1\;mg\;CO_2m^{-2}h^{-1}$ at the ridge site and $289.4\;mg\;CO_2m^{-2}h^{-1}$ at the southern slope, a difference of 52.6%. There was no significant difference in the Rs difference between slopes except for the first half of 2013, and both sites showed a tendency to increase exponentially as Ts increased. In addition, although the correlation is low, the difference in Rs between sites tended to increase as Ts increased. SMC showed a large fluctuation at the southern slope site relative to the ridge site, as while it was very low in 2013, it was high in 2011 and 2012. The accumulated litter of the soil surface and the SOMC at the depth range of 0~5 cm were $874g\;m^{-2}$ and 23.3% at the ridge site, and $396g\;m^{-2}$ and 19.9% at the southern slope site. Conclusions: In this study, Rs was measured for the ridge and southern slope sites, which have two different results where the surface litter layer is disturbed by strong winds. The southern slope site shows that the litter layer formed in autumn due to strong winds almost disappeared, and while in the ridge site, it became thick due to the transfer of litter from the southern slope site. The mean Rs was about two times higher in the ridge site compared to that in the southern slope site. The Rs difference seems to be due to the difference in the amount of litter accumulated on the soil surface. As a result, the litter layer supplied to the soil surface is disturbed due to the micro-topographical difference, as the slope and the change of the community structure due to the plant season cause heterogeneity of the litter layer development, which in turn affects SMC and Rs. Therefore, it is necessary to introduce and understand these micro-topographical features and mechanisms when quantifying and analyzing the Rs of an ecosystem.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.375-388
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• 2019

Accurate evaluation of sea-to-air $CO_2$ flux and its variability is crucial information to the understanding of global carbon cycle and the prediction of atmospheric $CO_2$ concentration. $fCO_2$ observations are sparse in space and time in the East Sea. In this study, we derived high resolution time series of surface $fCO_2$ values in the southwest East Sea, by feeding sea surface temperature (SST), salinity (SSS), chlorophyll-a (CHL), and mixed layer depth (MLD) values, from either satellite-observations or numerical model outputs, to three machine learning models. The root mean square error of the best performing model, a Random Forest (RF) model, was $7.1{\mu}atm$. Important parameters in predicting $fCO_2$ in the RF model were SST and SSS along with time information; CHL and MLD were much less important than the other parameters. The net $CO_2$ flux in the southwest East Sea, calculated from the $fCO_2$ predicted by the RF model, was $-0.76{\pm}1.15mol\;m^{-2}yr^{-1}$, close to the lower bound of the previous estimates in the range of $-0.66{\sim}-2.47mol\;m^{-2}yr^{-1}$. The time series of $fCO_2$ predicted by the RF model showed a significant variation even in a short time interval of a week. For accurate evaluation of the $CO_2$ flux in the Ulleung Basin, it is necessary to conduct high resolution in situ observations in spring when $fCO_2$ changes rapidly.