• Korean Journal of Poultry Science
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• v.48 no.1
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• pp.1-12
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• 2021

We investigated the effects of breed, laying age, and egg storage period on the vitality of chicks using the Hwanggalsaek Jaeraejong, Korean Rhode Island Red, and Korean White Leghorn chicken breeds. Their eggs were collected during the early laying period (27~29 weeks) and late laying period (50~52 weeks) and were stored for 3 days, 7 days and 14 days. After the eggs hatched, the hatching time, production performance, and organ weight of chicks were investigated. IL-6 gene expression level and relative length of telomeres were analyzed to determine the physiological activity of the chicks. HSP gene expression level and heterophil to lymphocytes ratio were also analyzed to examine the degree of stress response in the chicks. The results showed that breed and laying age influenced the vitality of chicks, but the egg storage period did not. Korean Leghorn chicks were considered the weakest breed in terms of vitality owing to their low survival rate, small heart size, low physiological activity, and high stress response level. Although the survival rate of chicks produced in the early laying period was low, their high physiological activity and low stress response indicated that they had a high vitality than the chicks produced in the late laying period. In conclusion, to obtain chicks with high vitality, it would be desirable to select a high vitality breed and avoid the use of chicks produced in the late laying period.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.101-110
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• 2004

The growth and niche breath of four species, i.e., native plants such as Bidens tripauita and B. bipinnata and naturalized plants such as B. frondosa and B. pilosa var. minor, were studied as related with environmental gradients including light intensity, soil moisture and soil nutrient. There were no significant differences in the phonology within each environmental gradients while considerable differences were found between species; the two naturalized species bloomed and produced fruit later than the two native species. Two naturalized species exhibited relatively higher total dry weight than the two native counterparts within all environmental gradients. Total dry weight showed positive responses to light intensity and soil moisture, and negatively to soil nutrient. The relative contribution of the environmental factors to total dry weight decreased in the order of soil nutrient, soil moisture and light intensity. Both B. bipinnata and B. pilosa var. minor showed significantly higher net assimilation rate (NAR) than other species. Also, NARs of B. bipinnata and B. pilosa var. minor decreased with increasing soil nutrient. Relative growth rate (RGR) decreased in order of B. tripartita, B. bipinnata, B. frondosa and B. pilosa var. minor in response to light intensity. In addition, RGRs of B. bipinnata and B. piEosa yay. minor increased in response to soil moisture, while those of B. pilosa var. minor and B. tripartita decreased with increment of soil nutrient. No significant fluctuations of shoot/root ratio were not observed in three species, but a native species, B. tripartita showed n decreased shoot/root ratio in response to soil nutrient. Comparing the growth characteristics of the species, B. pitosa var. minor and 3. tripartita revealed vigorous growth on barren soil. On the other hand, B. frondosa exhibited vigorous growth on fertile soil. Morphologically, B. tripartita adapted to light and required considerable moisture. On the contrary, the leaves of B. bipinnata did not change considerably in their area, although it preferred habitat with abundant light. In terms of niche breadth, B. bipinnata showed the widest ranges of 0.875 and 0.845 for light intensity and soil moisture gradients, respectively. B. pilosa var. minor showed a value of 0.933 for soil nutrient gradient. B. tripartita showed narrow ranges for the three environmental factors, whereas B. frondosa showed wide values for light intensity and soil nutrient, but relatively narrow value for soil moisture.

• Korean Journal of Heritage: History & Science
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• v.42 no.4
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• pp.96-111
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• 2009

This essay is a study aimed at rationality and utility of two terms, 'Nongak' and 'Pungmul'. I examined how the terms have been today, by diachrony based on review of historical material. I tried to secure the historical context and basis about my argument, quoting many historical material from Korea Dynasty period, Joseon Dynasty period and the colonial period of the imperial Japan during 1910-45 to today. I examined many objective arguments about the 'Nongak', and pointed out the mistake of the objective argument. And I examined the means and rationality of the terms, 'Nongak', 'Pungmul', 'Pungmulgut', 'Pungmulnory'. The 'Pungmul' has been used as the means of instrument for a long time from Joseon Dynasty period. It is only rational using as the means of instrument but as the means of Performance of Nongak considering the historical legitimacy. The 'Pungmul' is Sino-Korean word, not korean native letter. The Pungmulgut means the 'ritual by Pungmul', so it can be recognized the rationality, but have a weak point that it is a neologism being made by some intellectuals in 1980s. In addition to, it is not used im performing field. 'Pungmulnory' has a limit to call the Nongak as a synthetic art. 'Nongak'means a synthetic art that farmers who were absolute majority in agrarian society of Korea have made and developed. So I conclude that 'Nongak'is the best rational term.

• Korean Journal of Cognitive Science
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• v.29 no.4
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• pp.243-263
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• 2018

This research investigated whether inter-word spaces, the spaces between words, can affect the efficiency of Korean-speaking CSL(Chinese as a second language) learners in Chinese reading of Korean-speaking's ability to read Chinese. Through eye movement tracking experiments, CSL learners of different proficiency levels(beginning, intermediate, and advanced) and native Chinese readers were asked to read Chinese sentences with and without inter-word spaces. The tests analysed the participants' fixation counts and the time spent in reading each sentences and also between each words. In terms of the fixation counts and time spent between sentences, the results show that there were no significant difference in participants' fixation counts from reading sentences with and without inter-word spaces. The results also prove that reading sentences with inter-word spaces significantly shortened the reading time for both CSL learners and native Chinese readers. Even for the participants' fixation counts and time duration between each words, participants spent significantly less fixation counts and reading time while reading words with inter-word spaces. The results were more prominent and positive in tests conducted with CSL learners of lower proficiency. This research shows that inter-word spaces in Chinese texts can enhance the efficiency of chinese learners' reading ability.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.208-215
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• 2016

Vaccinium oldhamii Miq. is a Korean native tree, which is deciduous and shrub tree with broad leaf. Fruits were used primarily for edible or medicinal purposes for bladder infection in Korea and China. However, there is a lack of information on the degree of variation of phytochemical contents and antioxidant activity of these native clonal. We investigated morphological characteristics, phytochemical contents (polyphenol, flavonoid, anthocyanin) and antioxidant activity for the fruits of 24 individual variation from 4 different regions in Korea. The results in terms of horticultural traits and biochemical characteristics showed significant differences among populations and among individuals within population. The total phenolic contents ranged from 4.40 to 10.58 mg GAE/g and the total flavonoid contents ranged from 2.02 to 8.09 mg NE/g. The total anthocyanin contents ranged from 232.5 to 684.3 mg CGE/100g. Reducing power fruits ranged from 0.15 to 1.43 and DPPH free radical scavenging activity ranged from 49.1 to 97.5% at 400 ppm. Results revealed that the region of origin greatly influenced the phytochemical contents and antioxidant activity of V. oldhamii, which might help for the selection and validation of the most productive cultivars in the food and pharmaceutical industries.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.4
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• pp.62-69
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• 2013

The origin of natural planting, which is getting the spotlight in modern time facing natural and environmental problems, can be found from wild gardens. They were started by William Robinson and concretely embodied by Gertrude Jekyll. It is worth shedding new light on wild gardens, as they served as a pathbreaker for ecological design and an important foundation for the specialization of naturalism, which are part of the most important topics in modern gardens. This study aimed to infer the conceptual model of wild gardens and identify their historic significance by comparatively analyzing Robinson's Gravetye Manor and Jekyll's Munstead Wood. The results are: Firstly, they inherited inspirations for spatial organization from basic cottage gardens and introduced informal forms. Secondly, in terms of the use of materials, they had observed various climates in their journeys so that they could use both native and naturalized plants based on their understanding of the plants' hardiness and exotic species. They also displayed interests in plants in the woodlands and forests. Thirdly, in terms of design techniques, they investigated the colors and textures of individual plants and their relationships to produce a variety of views that resembled nature in microcosm. Fourthly, in terms of maintenance, their basic orientation was the minimum maintenance to allow plants to live according to their nature.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.1-13
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• 2007

The use of aquatic species in ecotoxicity research is well established in developed countries. However, there are limitations of using the species that are not native to Korea, and the toxicity data produced by domestic test species are significantly needed to reflect the domestic situation. The purpose of this study was to investigate the domestic species that can be applicable for the aquatic toxicity assessment in Korea. Aquatic toxicity data were collected in the framework of the project 'Development of integrated methodology for evaluation of water environment' to obtain a range of test species used for aquatic toxicity assessment internationally. The test species collected were evaluated in terms of domestic distribution based on the reliable references and the advices of experts. We figured out the 71 test species native to Korea. They included 7 fish, 26 invertebrates (2 annelids, 2 bryozoa, 13 crustaceans, 3 insects, 4 mollusc, 1 platyhelminth, and 1 protozoan), 26 plants (9 diatoms, 14 green algae, 3 macrophytes), and 12 others (2 amphibians, 3 bacteria, 6 blue-green algae, and 1 fungus). The result of this study should be a very useful information for ecotoxicity assessment in aquatic ecosystem, especially in choosing the test species applicable for the ecotoxicity in Korea hereafter.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.5
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• pp.20-30
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• 2003

This study is aimed at establishing the categories and items for ecological assessment and evaluation of the environmental friendliness of golf courses in the capital region of Korea. The categories and items for the assessment have been derived based on the existing literature and interviews with golf experts. This study covers 32 golf courses in the capital region of Korea that are available in terms of data and on-site surveys. In order to conduct a comprehensive assessment of the environmental friendliness of the golf courses, the assessment area was divided into 4 categories that include a total of 14 sub-categories. The 4 categories encompass 1) location, 2) topography, 3) vegetation, and 4) construction. As its sub-categories, the location category includes current land use and zoning in the National Land Use Management Law. Topography has 2 sub-categories in the damage ratio of existing topography, gradient, cut area, and slope height. The assessment of vegetation is largely based on site surveys in the categories of preservation of the existing vegetation, the use of natural resources and existing trees, the component ratio of native tree species, the multi-layered structure of vegetation, and the utilization of water purification plants. In the aspect of construction, afforestation on tile slopes and the utilization of existing surface soil were evaluated. The examination of comparative analysis among the 10 items as a ratio measure showed that the scores were low in the sub-categories of current land we, the use of existing trees, and the multi-layered structure of vegetation. However, the rating results were satisfactory in the 2 sub-categories including cut area, and the utilization of native tree species. Those proved to be contributing factors in the ecological health of the golf courses. According to correlation analysis of the 10 items to the overall ecological rating of each golf course, the sizes of the 32 golf courses were mainly affected by the damage ratio of existing topography, gradient, preservation of vegetation and slope height. This study has the initiative to conduct an ecological assessment of golf courses in the country based on site surveys. The study results revealed that location factors such as current land use, damage ratio of topography and gradient and topographical factors were the main factors affecting the environmental friendliness of golf courses. This indicates indicating the significance of these factors in the future construction practices of golf courses. Furthermore, this study raises the need for follow-up studies to establish more detailed assessment criteria and to develop assessment techniques for areas such as slope afforestation and water purification plants that need a qualitative approach.

• Journal of Wetlands Research
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• v.25 no.3
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• pp.196-204
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• 2023

Eleutherococcus gracilistylus is a designated rare plant by the Korea Forest Service, a deciduous broad leaf shrub native to the Gotjawal region, Jejudo. This study aimed to analyze the growth responses of E. gracilistylus to three environment factors such as light, moisture, and organic matter, and measure its ecological niche breadth. Based on these results, an attempt was made to identify suitable environmental conditions. E. gracilistylus exhibited increased above-ground length, leaf area, and plant leaf weight under intermediate conditions of light availability(L3, 50% of natural light), rather than very high or very low light conditions. Moisture availability and organic matter availability showed variations in growth responses in terms of leaf count and plant leaf weight. Under moisture availability, growth was favorable under or below intermediate conditions (M3, 240ml), while under organic matter availability, growth response was better above intermediate conditions (N3, 12%). Ecological niche breadth showed in the light factor(0.951), the moisture factor(0.977), and the organic matter content one(0.964). These results indicate that the preferred habitat of E. gracilistylus is somewhat shady, slightly dry, and has a lot of nutrients, and that the environmental factor that has the greatest impact on growth is the amount of light, which is considered to be a priority consideration for habitat management in its native area.

• Phonetics and Speech Sciences
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• v.9 no.3
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• pp.33-40
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• 2017

This study aimed to examine how Korean-English bilinguals make use of VOT and F0 cues in perception and production of Korean (lenis vs. aspirated) and English (voiced vs. voiceless) stops. It was explored whether bilinguals with extensive experience living in the U.S. exhibit native-like or interactive patterns in the cue use for both languages. Participants produced monosyllabic word-initial stops within a carrier sentence in each language, and performed forced-choice identification tasks with synthesized stimuli varying in 7 VOT steps and 7 F0 steps with base tokens of /$t^han$/ for Korean and /$t{\ae}n$/ for English. Listeners were required to select either /tan/ or /$t^han$/ for Korean and either /$d{\ae}n$/ or /$t{\ae}n$/ for English. The results from binary logistic regression analyses for each listener indicated that all bilinguals placed greater weight on F0 than VOT when distinguishing between the Korean lenis and aspirated stops, and greater weight on VOT than F0 in distinguishing between the English voiced and voiceless stops. In terms of production, all participants showed remarkably overlapping ranges in the VOT dimension and separating ranges in the F0 dimension for the stop contrast of Korean, while forming overlapping ranges in the F0 dimension and separating ranges in the VOT dimension for the stop contrast of English. These results indicate that the bilinguals with extensive exposure to L2 manage the stop systems of the two languages independently, both in perception and production, employing the opposite cue use for stops in the two languages. It was also found that the absolute beta-coefficient values of the perceptual cues for Korean stops were generally smaller than those for English and those reported in a previous study as for later bilinguals, which may have resulted from Korean not being their dominant language.