• Journal of the Korean Society of Tobacco Science
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• v.29 no.1
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• pp.1-7
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• 2007

This study was conducted in order to predict the chemical and physical properties by climatic factors during the growing season of flue-cured tobacco as soon as possible. The data of eight chemical and five physical properties were collected from "Analysis of physical and chemical properties on farm leaf tobacco" conducted at KT&G Central Research Institute from 1987 through 2006. Data of climatic factors from April to July in 10 districts were collected from Korea Meteorological Adminstration. Except for yellowness(b), all probabilities of linear regression equations between the climatic factors(X) and the average contents of twelve grades(whole plant) for chemical and physical properties(Y) were significant($P{\leq}0.05$). The predicable probabilities within ${\pm}20%$ range of difference were 100% in ether extract content, in nicotine content, and in filling value, 90% in total nitrogen content, and 70% in total sugar content. These results suggest that the regression equations may be useful to predict the average content of twelve grades for eight chemical and four physical properties by climatic factors during the growing season of flue-cured tobacco at the beginning of August.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.1
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• pp.8-13
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• 2007

This study was conducted in order to predict the chemical and physical properties by climatic factors during the growing season of burley tobacco as soon as possible. The data of six chemical and five physical properties were collected from "Analysis of chemical and physical properties on farm leaf tobacco" conducted at KT&G Central Research Institute from 1987 to 2006. Data of climatic factors from April to July in 6 districts were collected from Korea Meteorological Adminstration. Except for total nitrogen, total nitrogen/nicotine and yellowness(b), all probabilities of linear regression equations between the climatic factors(X) and the average contents of twelve grades(whole plant) for chemical and physical properties(Y) were significant($P{\leq}0.05$). The predicable probabilities within ${\pm}20%$ range of difference were 100% in ether extract content, 95% in nicotine content, and 90% in filling value. These results suggest that the regression equations may be useful to predict the average content of twelve grades for four chemical and four physical properties by climatic factors during the growing season of burley tobacco at the beginning of August.

• Journal of Korean Society of Forest Science
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• v.53 no.1
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• pp.1-26
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• 1981

1. Aiming at supply of basic informations on tree species siting and forest fertilization by understanding of soil properties that are demanded by each tree species through studies of forest soil's morphological, physical and chemical properties in relation to tree growth in our country, the necessary data have been collected in the last 10 years, are quantified according to quantification theory and are analyzed in sccordance with multi-variate analysis. 2. Test species, japanese larch (Larix leptolepis Gord) and the Korean white pine, (pinus koraiensis S et Z.) are plantable in extensive areas from mid to north in the temperate forest zone and are the two most recommended reforestation tree species in Korea. However, their respective site demands are little known and they have been in confusion or considered demanding the same site during reforestation. When the Korean white pine is planted in larch sites, it has shown relatively good growth, but, when Japanese larch is planted in Korean white pine site it can be hardly said that the Japanese Larch growth is good. To understand on such a difference soil factors have been studied so as to see how th soil's morphological, physical and chemical factors affect tree growth helped with the electronic computer. 3. All the stands examined are man-made mature forests. From 294 Japanese larch plots and 259 Korean white pine plots dominant trees are cut as samples and through stem analysis site index is determined. For each site index soil profiles are made in the related forest-land for analysis. Soil samples are taken from each profile horizon and forest-land productivity classification tables are worked out through physical and chemical analyses of the soil samples for each tree species for the study of relationships between physical, chemical and the combined physical/properties of soil and tree growth. 4. In the study of relationships between physical properties of soil and tree growth it is found out that Japanese larch growth is influenced by the following factors in the decreasing order of weight deposit form, soil depth, soil moisture, altitude, relief, soil type, depth a A-horizon, soil consistency, content of organic matter, soil texture, bed rock, gravel content, aspect and slope. For the Korean white pine the influencing factors' order is soil type, soil consistency, bed rock, aspect, depth of A-horizon, soil moisture, altitude, relief, deposit form, soil depth, soil texture, gravel content and slope. 5. In the study of relationships between chemical properties of soil and tree growth it is found out that Japanese larch growth is influenced by the following factors in the order of base saturation, organic matter, CaO, C/N ratio, effective $P_2O_5$, PH, exchangeable, $K_2O$, T-N, MgO, CEC, Total Base and Na. For the Korean white pine the influencing factors' order is effective $P_2O_5$, Total Base, T-N, Na, C/N ratio, PH, CaO, base saturation, organic matter, exchangeable $K_2O$, CEC and MgO. 6. In the study of relationships between the combined physical and chemical properties of soil and tree growth it is found out that Japanese larch growth is influenced by the following factors in the order of soil depth, deposit form, soil moisture, PH, relief, soil type altitude, T-N, soil consistency, effective $P_2O_5$, soil texture, depth of A-horizon, Total Base, exchangeable $K_2O$ and base saturation. For the Korean white pine the influencing factors' order is soil type, soil consistency, aspect, effective $P_2O_5$, depth of A-horizon, exchangeable $K_2O$, soil moisture, Total Base, altitude, soil depth, base saturation, relief, T-N, C/N ratio and deposit form. 7. In the multiple correlation of forest soil's physical properties larch's correlation coefficient for Japanese Larch is 0.9272 and for Korean white pine, 0.8996. With chemical properties larch has 0.7474 and Korean white pine has 0.7365. So, the soil's physical properties are found out more closely related with tree growth than chemical properties. However, this seems due to inadequate expression of soil's chemical factors and it is proved that the chemical properities are not less important than the physical properties. In the multiple correlation of the combined physical and chemical properties consisting of important morphological and physical factors as well as chemical factors of forest soils larch's multiple correlation coefficient is found out to be 0.9434 and for Korean white pine it is 0.9103 leading to the highest correlation. 8. As shown in the partial correlation coefficients Japanese larch needs deeper soil depth than Korean white pine and in the deposit form of colluvial and creeping soils are demanded by the larch. Moderately moist to not moist should be soil moisture and PH should be from 5.5 to 6.1 for the larch. Demands of T-N, soil texture and soil nutrients are higher for the larch than the Korean white pine. Thus, soil depth, deposit form, relief, soil moisture, PH, N, altitude and soil texture are good indicators for species sitings with larch and the Korean white pine while soil type and soil consistency are indicative only limitedly of species sitings due to their wide variations as plantation environments. For the larch siting soil depth, deposit form, relief, soil moisture, pH, soil type, N and soil texture are indicators of good growth and for the Korean white pine they are soil type, soil consistency, effective $P_2O_5$ and exchangeable $K_2O$. In soil nutrients larch has been found out demanding more than the Korean white pine except $K_2O$, which is demanded more by the Korean white pine than Japanese larch generally. 9. Physical properties of soil has been known as affecting tree growth to the greatest extent so far. However, as a result of this study it is proved through computer analysis that chemical properties of soil are not less important factors for tree growth than chemical properties and site demands for the Japanese larch and the Korean white pine that have been uncertain so far could be clarified.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.201-205
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• 2001

설악산 국립공원지역 산간계류의 17지점에서 2000년 6월부터 2001년 6월까지 어류상 및 이화학적 요인 분석을 실시하였다. 모든 조사지점은 1-3차 이내의 하천으로 비교적 물리ㆍ화학적 교란이 적었으며 하천폭은 5～30 m 정도였다. 채집된 어류는 총 17과 42종 2,557개체였고, Cyprinidae는 16종 2,165개체가 채집되어 84.7%의 상대풍부도를 나타냈으며, Cobitidae는 5종으로 Cyprinidae 다음으로 가장 많은 종이 채집되었으나 개체수는 109개체로 4.2%의 상대풍부도를 보였다. Gobiidae가 4종 (5.0%), Salmonidae는 모두 3종 (0.8%)이 채집되었다. 이외에도 Oryziatidae, Plecoglossidae, Amblycipitidae, Cottidae, Serranidae 등 12과는 각각 1종씩 모두 117개체 (4.6%)가 채집되었다. Cyprinidae는 전체 채집종의 37.2%를 나타냈다. 우점종은 Zacco temmincki로 10개 지점에서 738개체가 채집되어 28.9%의 상대풍부도를 나타냈으며, 아우점종은 Moroco kumtangensis와 Z.platypus로 각각 4개 지점 648개체 (25.3%)와 7개 지점 344개체 (13.5%)로 나타났다. 한국고유종 (Korean endemic species)은 모두 4과 11종 781개체로 30.5%의 상대풍부도를 나타냈으며, 고유화 빈도는 25.6%로 한국의 평균 고유화 빈도와 유사하게 나타났다 우점종은 M. kumkangensis (한국고유종 중 83.1%)로 나타났으며, 아우점종은 Coreoperca herzi (5.8%), Microphysogobio longidorsalis (3.8%)와 Coreloeuciscus splendidus (2.6%)로 나타났다. 본 조사에서 외래어는 채집되지 않았다. 어류의 다양성은 국립공원내에서보다 하천폭이 커지고 서식처자 비교적 다양한 경계지역의 하천 조사지점에서 더 높게 나타났다.따라서 국립공원의 경계지역에 대한 효율적인 생태적 관리가 요구되며, 국립공원 내의 어류의 다양성 유지와 회복을 위해서는 공원 내는 물론 경계지역 산지하천의 물리적 변형 (보, 제방, 석축 등)과 오염원의 유입 (점, 비점오염원)에 대한 고려가있어야 한다.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.297-301
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• 2003

An inhibitor of squalene synthase, a key enzyme in the cholesterol biosynthetic pathways and a target for improved agents to lower plasma levels of low-density lipoprotein, was sequentially purified from Curcuma longa by acetone extraction, silica gel column chromatography, and sephadex LH-20 column chromatography. Active compound, YUF-01, was successfully purified and analyzed as $C_{20}H_{21}O_6$ by electron ionization mass spectrum. Through $^1H-NMR$ and $^{13}C-NMR$ analyses, YUF-01 was identified as curcumin, which showed strong inhibition of squalene synthase.

• Phonetics and Speech Sciences
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• v.11 no.1
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• pp.9-18
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• 2019

The purpose of this study is to determine whether the mean fundamental frequency (F0) changes depending on language, task, or language proficiency for Korean-English bilinguals. A total of forty-eight Korean-English speakers (28 balanced bilinguals and 20 Korean dominant bilinguals) participated in the study. Participants were asked to read aloud two types of tasks in English and Korean. For statistical analyses, the language ${\times}$ task two-way repeated ANOVAs were conducted within the balanced bilingual group first, and then group ${\times}$ language two-way mixed ANOVAs. The results showed that the females in both bilingual groups changed their mean F0 depending on the language they used and the tasks (p<.05), whereas no significant results were found in the males in either group under any conditions. The mean fundamental frequency in the Korean reading task was significantly higher than that in the English reading task for females in both balanced and Korean dominant bilingual groups. Thus, changes in mean F0 depending on language and context may reflect gender-specific characteristics, and females seem to be more sensitive to the socio-cultural standards that are imposed on them.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.550-556
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• 2016

Groundwater heat pump (GWHP) systems must consider phenomena such as clogging to improve system efficiency and maintenance. In this study, we evaluated the prokaryotic diversity in a boring slime sample obtained at a depth of 10 m, which represented an undisturbed sample not affected by aquifer drawdown. Bacteria belonging to the phyla Proteobacteria (20.8%), Acidobacteria (18.8%), Chloroflexi (16.9%), and Firmicutes (10.2%) were found. Additionally, 144 species were identified as belonging to the genus Koribacter. Archaeal phyla were detected including Thaumarchaeota (42.8%), Crenarchaeota (36.9%), and Euryarchaeota (17.4%) and the class level comprised the miscellaneous Crenarchaeota group (MCG), Finnish forest soil type B (FFSB), and Thermoplasmata, which collectively accounted for approximately 69.4% of the detected Archaea. Operational taxonomic units (OTUs) were analyzed to reveal 3,565 bacterial and 836 archaeal OTUs, with abundances of 7.81 and 6.68, and richnesses of 5.96E-4 and 2.86E-3, respectively. The distribution of the groundwater microbial community in the study area showed a higher proportion of non-classified or unidentified groups compared to typical communities in surface water and air. In addition, 135 (approx. 1.9%) reads were assigned to a bacterial candidate associated with clogging.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.398-405
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• 2022

The research was based on long-term studies on the major physico-chemical and hydrological factors and zooplankton community dynamics in the Hwang River. We had 341 times survey and collected zooplankton samples in the Hwang River of mid-Nakdong River from 1995 to 2013. We identified 97 zooplankton species, including 77 rotifers, 16 cladocerans, and 4 copepods. The total zooplankton abundance and species diversity were shown distinctive temporal variation (ANOVA, p<0.001). Annual average of zooplankton population density was 58.4±3.2 ind L^-1 (n=341) and the lowest was 17.0±3.8 ind L^-1 (1996, n=20), while the highest was 151.5±32.3 ind L^-1 (2010, n=22). For zooplankton, small rotifer groups(e.g., Keratella sp., Brachionus sp., Trichotria sp.) dominated the study site for 19 years survey. Statistical analysis revealed that there were positive relationships with SiO₂ (p=0.002) and water level (p<0.001) for the high abundance of rotifer community. There were considerable variations both the total cladocerans population and the number of cladocerans' species concerning annual precipitation. Despite the appearance of various zooplankton in the Hwang River, the mean population density remained low. Due to the lateral structures in the Nakdong River, the downstream basin of the Hwang River is inevitably affected. The zooplankton community in our study site is considered to be mainly influenced by external factors that can stably increase and maintain the volume of the water body and internal factors that induce an increase in food sources through the inflow of nutrients into the water body.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.714-723
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• 2020

This study was conducted to investigate the community stability and similarity of benthic macroinvertebrates in the Giran stream between August and September 2018, and compare results to those reported by Lee (2004). As relates to the total number of species in each taxon in 2018, 45 species were additionally discovered compared to the 2003 study; the number of EPT taxa increased by 14 species and OCH taxa increased by 18 species. The diversity and richness indexes increased while the dominance index tended to decrease. According to analysis of functional feeding groups, 11 more Gathering-collector species were found, making it the highest functional feeding group with 24 species. According to analysis of functional habitat groups, 15 more clinger species were found than in the past, making it the highest functional habitat group with 41 species. A community stability comparison showed that species belonging to 'Stability Group I' had the highest stability rate at 57.1% in 2003 and 61.5% in 2018. According to the biological water quality assessment, in 2018, the average water quality level at each survey site was 'Ia' and 'Very Good' in terms of environmental conditions. As a result of the similarity analysis between the survey points for the species that appeared, two large groups of similarities were classified (similarity group 1: 2003 sites, similarity group 2: 2018 sites).

• Journal of the Korean Society of Food Culture
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• v.16 no.2
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• pp.180-186
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• 2001

The purpose of this study was to investigate the sensory and physicochemical attributes of Cham-chwi dduk with various amounts of Cham-chwi(Aster scaber) and salt. Cham-chwi dduk was made by steaming glutinous rice flour with Cham-chwi powder for 15 min. Cham-chwi powder was added 1, 3, 5% of glutinous rice flour weight and salt was added 0.5, 1.0 1.5%. According to the sensory evaluation, bitterness and Cham-chwi flavor increased as the amount of Cham-chwi increased and saltiness increased as the amount of salt increased(p<0.05). In the textural profiles, chewiness, adhesiveness, hardness and gumminess were highest when 3% Cham-chwi was added. The moisture content of Cham-chwi dduk was increased as the amount of Cham-chwi was increased and the amount of salt was decreased. The more amount of added Cham-chwi increase, the more green color was strong and yellow color was weak. These results were used to determine the optimum conditions of adding levels of Cham-chwi and salt. Conditions were standardized with minimum range of firmness when expected value of Cham-chwi flavor was more than six and expected value of bitterness was less five. The optimum conditions of Cham-chwi dduk was established as the 3.1% Cham-chwi and 0.6% salt.