• Korean Journal of Soil Science and Fertilizer
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• v.24 no.1
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• pp.61-68
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• 1991

Thirty Bradyrhizobium japonicum isolates (10 strains per each soil) from 1 uncultivated [Sangnam(Soil 1), Milyang]- and 2 cultivated [Dong(Soil 2)and Chinbuk(Soil 3), Changweon] upland soils in Yeongnam area were evaluated on their symbiotic effectiveness to soybean [Glycin max (L.)] cv. Korean Jangbaekkong and American Clark and examined on their serological diversity. The results obtained were summarized as follows : 1. On symbiotic effectiveness of B. japonicum with plant genotypes, isolates showed a relatively high value of nodule mass in Jangbaekkong cv. and of shoot dry weight and total nitrogen in Clark cv. demonstrating the order of Soil 1> Soil 2> Soil 3 isolates. 2. Among 30 B. japonicum isolates, YCK 141 showed the best effectiveness on mean nitrogen fixation of two cultivars. 3. Thirty indigenous B. japonicum showed 6 types of serological diversities in the immunoblot analysis which were present in various proportions at Soil 2(5) and Soil 3(5) except Soil 1 where all isolates fell into the YCK 117 serogroup. And their distribution order was serotype YCK 117( 12 strains) > USDA 1l0(5strains), USDA 123(5 strains) > YCK 150(4 strains) > YCK 141(3 strains) > YCK 226(1 strain). 4. Especially, 10 isolates from Soil 1, an uncultivated orchard, showed a very homologous pattern in not only effectiveness but serological distribution. It seemed to indicate that the isolates were typically affected by numerous physical and environmental factors of the soil.

• Journal of the Korean earth science society
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• v.41 no.1
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• pp.19-30
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• 2020

To understand the impact of typhoons on Gamji gravel beach Taejongdae in Busan, we carried out beach profiling using a VRS-GPS system and a Drone photogrammetry for the typhoons 'Kong-rey' invaded in October 2018 and 'Danas' in July 2019. In addition, grain sizes are analyzed to investigate the overall distribution pattern of gravels on the beach, and the beach topography is surveyed periodically to confirm the recovery rate of the beach. Grain-size analysis reveals that mean gravel sizes, in general, become finer from -6.2Φ to -5.4Φ towards the east in the seashore line direction. Variation in mean sizes is obviously observed in the cross-shore direction. Gravels in the swash zone are relatively fine about -4.5Φ in size and equant in shape, whereas the coarse and oblate gravels ranged from -5Φ to -6Φ are found in the berm. Gamji gravel beach particularly has two lines of berms: a lower berm situated facing beach and an upper berm about 10 m landward. After the typhoon Kong-rey passed by, about 1.4 m of severe erosion in upper berm occurred, and the berm eventually disappeared. On the backshore of the upper berm about 50 cm of erosion took place so that the elevation became lower. However, tangible erosion was not observed in the lower berm. When typhoon Danas hit, rated as mild storm, both upper and lower berm were eroded out. However, about 50 cm of deposition occurred only in the backshore. Only three days later, the new lower berm was formed, meaning that sedimentation rate must be high. This result indicates that Gamji gravel beach is recovered very fast from erosion caused by the typhoons when it is under the fair-weather condition even though beach morphology changes dramatically in a short period of time. Gravel beach is estimated to be or evaluated very resilient to typhoon erosion.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.4
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• pp.302-307
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• 2001

The underwater background noise measured in Geoje and Tongyoung diving fishing ground from May to December, 2000 and analyzed to get optimum carrier frequency and transmitter power level for underwater wireless telephone design. The results obtained are summarized as follows: 1. At the Geoje and Tongyoung diving fishing ground, the lowest ambient noise band was 25~30kHz with 57dB and 52dB re 1$\mu$Pa, respectively. 2. At the Geoje and Tongyoung diving fishing ground, the lowest noise band during fishing activity was 67dB and 62dB re 1$\mu$Pa, respectively. 3. At the Geoje diving fishing ground, the noise of water jetter which is a digging machine for subbottom shells was 102dB re 1$\mu$Pa. 4. Considering the design parameters of underwater wireless telephone, it is found that the optimum carrier frequency band is around 30kHz and the transmitter source level should be at least 131dB re 1$\mu$Pa for 500m range telephone.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.4
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• pp.121-131
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• 2008

This study was conducted to delineate temporal and spatial patterns of potential risk of cold injury by combining the short-term cold hardiness of Campbell Early grapevine and the IPCC projected climate winter season minimum temperature at a landscape scale. Gridded data sets of daily maximum and minimum temperature with a 270m cell spacing ("High Definition Digital Temperature Map", HD-DTM) were prepared for the current climatological normal year (1971-2000) based on observations at the 56 Korea Meteorological Administration (KMA) stations using a geospatial interpolation scheme for correcting land surface effects (e.g., land use, topography, and elevation). The same procedure was applied to the official temperature projection dataset covering South Korea (under the auspices of the IPCC-SRES A2 and A1B scenarios) for 2071-2100. The dormancy depth model was run with the gridded datasets to estimate the geographical pattern of any changes in the short-term cold hardiness of Campbell Early across South Korea for the current and future normal years (1971-2000 and 2071-2100). We combined this result with the projected mean annual minimum temperature for each period to obtain the potential risk of cold injury. Results showed that both the land areas with the normal cold-hardiness (-150 and below for dormancy depth) and those with the sub-threshold temperature for freezing damage ($-15^{\circ}C$ and below) will decrease in 2071-2100, reducing the freezing risk. Although more land area will encounter less risk in the future, the land area with higher risk (>70%) will expand from 14% at the current normal year to 23 (A1B) ${\sim}5%$ (A2) in the future. Our method can be applied to other deciduous fruit trees for delineating geographical shift of cold-hardiness zone under the projected climate change in the future, thereby providing valuable information for adaptation strategy in fruit industry.

• Korean Journal of Medicinal Crop Science
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• v.13 no.6
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• pp.226-233
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• 2005

This study was carried out to evaluate the fruit and growth characteristics of selecting Vitis amurensis through functional material analysis and sensory evaluation in V. amurensis collected in Gangwondo. For evaluation of growth characteristics in V. amurensis, experiments were carried out by compared with the two grape cultivars 'Campbell Early' and 'Kyoho'. The full bloom and verasion time in V. amurensis was investigated faster than those of examined cultivar grapes, while harvest time was investigated latter than those of examined cultivar grapes, but agronomic characteristics was not thought significantly difference between cultivar grapes and V. amurensis. For evaluation of shoot growth phase, the growth curve was very similar to cultivar grapes. The berry size in V. amurensis showed that increases rapidly between 3 and 4 days after full bloom time, and approximately doubles between the second growth period and harvest time, and the berry development phase investigated that consist of two sigmoid growth periods separated by a lag phase. The berry weight and soluble solids in V. amurensis increased with the tree age, but acidity and total sugar contents decreased, and showed a special quality and stable growth according to vine age. To investigation of functional materials, the anthocyanin content in V. amurensis ranged from 16.6 to 50.2 mg/100 g, and the resveratrol content ranged from 0.143 to $0.236{\mu}g/100\;g$ which was higher than those of cultivar grapes. These result indicated that V. amurensis tended to have the useful material larger than cultivar grapes. Therefore, other edibility factors of V. amurensis collected in Gangwondo may contribute to breeding studies in Vitis. spp.

• 한국노년학
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• v.40 no.4
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• pp.729-746
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• 2020

For the development and better use of information and communication technology(ICT) for promoting health and quality of life in older people, it is important to understand personal factors associated with ICT use. The aims of this study were to describe the pattern of ICT use according to health characteristics of elderly and to investigate significant factors related to ICT use among three age groups. The data of 2017 National Survey of Older Koreans was used for analysis and 10,058 of older adults aged 65 and over were included for study participants. As results, first, the young old(65~74) used more functions of ICT than the middle-old(75~84) and the old-old(85 and over). Second, ICT was more used among older people with good conditions in chronic disease, subjective health, cognition, depression, vision, hearing, walking and IADL. Third, higher prevalence of ICT use was significantly associated with age, education, household income, subjective health, depression, cognitive function, vision limitation and walking limitation. Fourth, factors influencing the use of ICT were a little different among three age groups. For the young-old(65~74), subjective health, depression, cognitive decline, walking limitation, and IADL disability were significant factors affecting on ICT use. For the middle-old(75-84), subjective health, depression, cognitive decline, vision, hearing, and walking limitation were related with their ICT use. For the old-old(85 and over), only cognitive function and depression were associated with their ICT use. Based on these results, this study suggested the need to consider multiple health conditions for developing and using ICT for older adults.

• Journal of agricultural medicine and community health
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• v.29 no.1
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• pp.1-14
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• 2004

Objectives: We investigated the factors related to health examination behaviors, sociodemographic aspects and lifestyles of elderly persons with different social backgrounds, and compared sexual and regional differences in urban and rural elderlies. Methods: The total study subjects(464 individuals) from urban(236) and rural areas(228), recruited by a stratified cluster random sampling were interviewed and examined about their sociodemographic profiles, daily lifestyles, subjective health status, conditions concerning use of medical resources, hearing acuity, visual acuity and ADL(activity of daily living), and whether they receive health examination or not. For statistical analysis, Chi-square test was used for sexual and regional comparisons among the groups who have been given a health examination and the one who have not. Results: In urban areas, the rate of having underwent health examination was 54.5% in men and 46.9% in women, and in rural areas, it was 59.8% in men and 42.7% in women, showing its higher rate in men than in women in both areas. For regional differences between the group who have taken a health examination and the one who have not, there was a significant difference in terms of age, family pattern, current job, monthly household income, owning a house, drinking status, eating habit, subjective health status, whether they have taken outpatient medical service for the recent 3 months or not, anxiety for the health, and IADL conditions according to whether the community is rural or urban. In multiple regressions, the influential factors on the health examination behaviors were selected such as having their own house, their family doctor, amnesia, urinary incontinence and chronic disease in urban districts. But in rural districts, the variables were selected such as having or not of their family doctor, urinary incontinence, anxiety for the health, educational level, their own house and chronic disease. Conclusions: It is suggested that the approach to the health examination of an older patient requires substantial consideration of highly variable individual sociodemographic characteristics involving regional attributes as well as their daily life styles, subjective health status, status of performing health examination, physical health status and ADL conditions.

• Restorative Dentistry and Endodontics
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• v.33 no.2
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• pp.98-106
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• 2008

The purpose of this study was to evaluate whether intracanal irrigation method could affect the adhesion between intracanal dentin and root canal filling materials (Gutta-percha/AH 26 sealer and Resilon/Epiphany sealer). Thirty extracted human incisor teeth were prepared. Canals were irrigated with three different irrigation methods as a final rinse and obturated with two different canal filling materials (G groups: Gutta-percha/AH 26 sealer, R groups: Resilon/Epiphany sealer) respectively. Group G1, R1-irrigated with 5.25% NaOCl Group G2, R2-irrigated with 5.25% NaOCl, sterile saline Group G3, R3-irrigated with 5.25% NaOCl, 17% EDTA, sterile saline Thirty obturated roots were horizontally sliced and push-out bond strength test was performed in the universal testing machine. After test, the failure patterns of the specimens were observed using Image-analyzing microscope. The results were as follows. 1. Gutta-percha/AH 26 sealer groups had significantly higher push-out bond strength compared with the Resilon/Epiphany sealer groups (p < 0.05). 2. Push-out bond strength was higher when using 17% EDTA followed by sterile saline than using NaOCl as a final irrigation solution in the Resilon/Epiphany sealer groups (p < 0.05). 3. In the failure pattern analysis, there was no cohesive failure in Group G1, G2, and R1. Gutta-percha/AH 26 sealer groups appeared to exhibit predominantly adhesive and mixed failure patterns, whereas Resilon/Epiphany sealer groups exhibited mixed failures with the cohesive failure occurred within the Resilon substrate.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.2
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• pp.191-200
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• 2011

Four ruminally cannulated Hanwoo steers (BW 600 ${\pm}$ 48.4 kg) fed whole crop rice silage (WRS) as forage were used to investigate the effects of its dietary on rumen fermentation and blood metabolites at different harvesting time such as milk, dough, yellow ripe and mature stages of WRS, respectively. Mean ruminal pH sampled at 0, 1, 2, 4, 6 and 8 h after the morning feeding was not significantly (p>0.05) different between the WRS by the harvesting time. In diurnal pattern in ruminal pH, the lowest pH for the mature stage treatment (Mature) appeared at 6 h after the feeding while it appeared at 2-4 h for the other treatments. This may indicate that retention time in the rumen of Hanwoo fed WRS harvested at the Mature increased. Although feeding WRS harvested at different stages did not significantly (p>0.05) affect ruminal ammonia N concentration, the ammonia N for WRS harvested at the milk stage (Milk) tended (p=0.11) to decrease compared with that for the yellow stage treatment (Yellow). In the blood metabolites analysis, BUN concentration for Yellow numerically decreased compared with that for Milk. This, taking lower concentration of ruminal ammonia N for Milk than the other treatments into account, clearly indicates that the BUN concentrations may not increase in proportion to ruminal ammonia N concentration according to ammonia N concentration entering into the lower gastric tracts. Lower (p=0.03) concentration of blood albumin for the dough stage treatment than that for Mature may indicate high protein synthesis in Hanwoo fed WRS at the dough stage, but further studies in terms of mechanism of nutrients distribution should be required. Present results indicate that different harvesting time did not affect rumen fermentation and blood metabolites in Hanwoo. Thus, based on the results of the present and the previous studies, utilizing WRS harvested at yellow stage could be recommendable for Hanwoo steers.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.307-319
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• 2016

A Land-Atmosphere Modeling Package (LAMP) for supporting agricultural and forest management was developed at the National Center for AgroMeteorology (NCAM). The package is comprised of two components; one is the Weather Research and Forecasting modeling system (WRF) coupled with Noah-Multiparameterization options (Noah-MP) Land Surface Model (LSM) and the other is an offline one-dimensional LSM. The objective of this paper is to briefly describe the two components of the NCAM-LAMP and to evaluate their initial performance. The coupled WRF/Noah-MP system is configured with a parent domain over East Asia and three nested domains with a finest horizontal grid size of 810 m. The innermost domain covers two Gwangneung deciduous and coniferous KoFlux sites (GDK and GCK). The model is integrated for about 8 days with the initial and boundary conditions taken from the National Centers for Environmental Prediction (NCEP) Final Analysis (FNL) data. The verification variables are 2-m air temperature, 10-m wind, 2-m humidity, and surface precipitation for the WRF/Noah-MP coupled system. Skill scores are calculated for each domain and two dynamic vegetation options using the difference between the observed data from the Korea Meteorological Administration (KMA) and the simulated data from the WRF/Noah-MP coupled system. The accuracy of precipitation simulation is examined using a contingency table that is made up of the Probability of Detection (POD) and the Equitable Threat Score (ETS). The standalone LSM simulation is conducted for one year with the original settings and is compared with the KoFlux site observation for net radiation, sensible heat flux, latent heat flux, and soil moisture variables. According to results, the innermost domain (810 m resolution) among all domains showed the minimum root mean square error for 2-m air temperature, 10-m wind, and 2-m humidity. Turning on the dynamic vegetation had a tendency of reducing 10-m wind simulation errors in all domains. The first nested domain (7,290 m resolution) showed the highest precipitation score, but showed little advantage compared with using the dynamic vegetation. On the other hand, the offline one-dimensional Noah-MP LSM simulation captured the site observed pattern and magnitude of radiative fluxes and soil moisture, and it left room for further improvement through supplementing the model input of leaf area index and finding a proper combination of model physics.