• Economic and Environmental Geology
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• v.15 no.3
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• pp.155-166
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• 1982

Sulfur isotope compositions (${\delta}^{34}S$) of seventy one sulfide minerals from the Shinyemi ore deposits were determined to range from -10.1 to +5.0‰ with a mean value of +2.1‰. These values are roughly comparable to those of various hydrothermal ore deposits in Korea, about +2.0 to +7.0‰ in ${\delta}^{34}S$, suggesting that they are to be same in source of sulfur. The Shinyemi deposits are grouped into two types; the western bedded skarn orebodies and the eastern small pipes and veins. The ${\delta}^{34}S$ values of sulfide minerals from the bedded orebodies (early mineralization) are ranging from -10.1 to +2.5‰, which is relatively wide in range, whereas those of the pipes and veins. (later mineralization) have a narrow range of ${\delta}^{34}S$ values, +2.7 to +5.0‰, regardless of the kind of sulfide minerals. Isotopic temperature obtained from the sphalerite-galena mineral pairs of the New B orebody appeared to be about 400 to $540^{\circ}C$ are reasonably good agreement with the comparable data of skarn mineral assemblages. It is concluded that the west orebodies were formed in earlier stage at higher temperatures than the east orebodies formed later at lower temperatures. Judging from the various data from the present study, the Shinyemi deposits can be defined as a typical contact metasomatic deposit. The source of sulfur in the hydrothermal solutions is considered to be comagmatic with the Shinyemi granodiorite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.194-200
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• 2007

The purpose of this study was to observe the effects of fiber free control diet (CD), cellulose diet (CED) and pectin diet (PTD) on diet induced thermogenesis (DIT) in healthy Korean woman for 3 hours. The three test diets were as follows: CD (carbohydrate intake: 63.4% of energy, protein intake: 14.0% of energy and fat intake: 25.8% of energy), CED (carbohydrate intake: 62.5% of energy, protein intake: 14.0% of energy and fat intake: 26.1% of energy) and PTD (carbohydrate intake: 62.7% of energy, protein intake: 14.0% of energy and fat intake: 26.2 of energy). Groups were served 10 g of cellulose for CED and 10 g of pectin for PTD, respectively. DIT was measured at fasting state and at 30, 60, 90, 120, 150 and 180 min after consuming each diet. The mean age of all subjects was $22.3{\pm}1.9$ years. Body weight was $52.5{\pm}8.6$ kg and body mass index was $20.6{\pm}2.7kg/m^2$. Preprandial resting energy expenditure was $0.79{\pm}0.02kcal/min$ and postprandial DIT were $14.05{\pm}0.62%$ for CD, $9.33{\pm}0.62%$ for CED, $11.07{\pm}1.35%$ for PTD as a percentage of the energy load. DIT of CD was significantly higher than those of CED and PTD. There was no significant difference in postprandial change in body temperature after consuming each test diets and the sympathetic nervous system activity measured by heart rate was significantly higher in CD than CED and PTD (p<0.05). With this study, it can be concluded that CED and PTD have significantly lowered in DIT (p<0.05). We didn't show the correlation of the factors that relate in DIT; thus, further experiments on that matter should be followed.

• Food Science and Preservation
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• v.14 no.4
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• pp.414-418
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• 2007

The physicochemical characteristics and sensory properties of Deodeok wine, formed by leaching of Deodeok at room temperature for 180 days, were investigated over the following range of Deodeok levels: 10, 15 and 20% (all w/v). The higher the level of Deodeok, the greater were the final values of total sugars, reducing sugars, total polyphenols, and crude saponins. The Hunter's b-value (yellowness) of Deodeok wine varied markedly with Deodeok levels, and yellowness was highest in Deodeok wine containing 20% (w/v) Deodeok. Non-volatile compounds, that form the basis of the liquor tax law, were 0.64, 1.38 and 2.11% (all w/v), respectively, at day 160. Of these values, that of 2.11% (w/v), the level of non-volatile compounds in Deodeok wine containing 20% (w/v) Deodeok, was in accord with the liquor tax law (that requires this figure to be 2.0%). Sensory evaluation showed that Deodeok wine containing 20% (w/v) Deodeok was superior to the other wines tested.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.521-525
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• 2001

This study investigated the effects of conventional predrying and modified atmosphere (MA) on the head quality and storability of Chinese cabbage 'Norang' cultivar. Immediately after harvest, heads were predried for 2 days and MA stored in $50{\mu}m$ PE film packages at $4^{\circ}C$. MA packaging restrained Hunter L and b values of Chinese cabbage more effectively than non-packaging during storage at $4^{\circ}C$. But there was little change between the two treatments. Fresh weight decreased less in heads treated with predrying and MA than non-treatment during storage. Predried Chinese cabbage heads kept a high level of soluble solids in 4 weeks of storage, while non-packaging maintained high contents of soluble solids for 6 weeks of storage period. Chinese cabbage heads contained 7.0 mg/gFW glucose, 6.3 mg/gFW fructose, and 0.6 mg/gFW sucrose as major soluble sugars at harvest. The content of sugars decreased immediately after predrying and increased steadily after 2 weeks storage. It was found inappropriate to assess head quality of Chinese cabbage by investigating was investigated by Hunter a, firmness, dry matters content, pH, and soluble sugars after predrying and MA package. Marketability of Chinese cabbage was lost when heads were stored at room temperature in 2 weeks. It showed poor appearance of heads stored at $4^{\circ}C$ in 7 weeks. Decay occurred in Chinese cabbage stored in MA under excessive relative humidity. Predried head showed good appearance during storage at $4^{\circ}C$ for 7 weeks. As a result, Chinese cabbage heads can be successfully stored for at least 7 weeks with predrying and MA storage.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.215-231
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• 2020

Forest landscape models (FLMs) can be used to investigate the complex interactions of various ecological processes and patterns, which makes them useful tools to evaluate how environmental and anthropogenic variables can influence forest ecosystems. However, due to the large spatio-temporal scales in FLMs studies, parameterization and validation can be extremely challenging when applying to new study areas. To address this issue, we focused on the parameterization and application of a spatially explicit forest landscape model, LANDIS-II, to Mt. Gyebang, South Korea, with the use of the National Forest Inventory (NFI) and long-term ecological research (LTER) site data. In this study, we present the followings for the biomass succession extension of LANDIS-II: 1) species-specific and spatial parameters estimation for the biomass succession extension of LANDIS-II, 2) calibration, and 3) application and validation for Mt. Gyebang. For the biomass succession extension, we selected 14 tree species, and parameterized ecoregion map, initial community map, species growth characteristics. We produced ecoregion map using elevation, aspect, and topographic wetness index based on digital elevation model. Initial community map was produced based on NFI and sub-alpine survey data. Tree species growth parameters, such as aboveground net primary production and maximum aboveground biomass, were estimated from PnET-II model based on species physiological factors and environmental variables. Literature data were used to estimate species physiological factors, such as FolN, SLWmax, HalfSat, growing temperature, and shade tolerance. For calibration and validation purposes, we compared species-specific aboveground biomass of model outputs and NFI and sub-alpine survey data and calculated coefficient of determination (R²) and root mean square error (RMSE). The final model performed very well, with 0. 98 R² and 8. 9 RMSE. This study can serve as a foundation for the use of FLMs to other applications such as comparing alternative forest management scenarios and natural disturbance effects.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.264-270
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• 2012

This study was performed to compared the effectiveness of individual treatments (electrolyzed water: EW, organic acid, and ultrasound) and their combination on reducing foodborne pathogens from perilla leaves. Perilla leaves were innoculated with a cocktail of Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus. Inoculated perilla leaves were treated with EW combined with different concentration of acetic acid (0.5%, 1.0%, 1.5%, 2.0%) for 1 min at room temperature. Treatment of 3 pathogens on perilla leaves with electrolyzed water combined with ultrasound (25 kHz) and 0.5% acetic acid was also performed for 1 min. While the numbers of S. Typhimurium and B. cereus showed reduced with increasing acetic acid concentration, there is no difference in the number of S. aureus treated with EW containing 0.5% to 1.5% acetic acid. Discoloration was observed the perilla leaves treated with EW combined with more than 1.0% acetic acid. For all three pathogens, the combined treatment of EW and ultrasound resulted in additional 0.42 to 0.72 $log_{10}$ CFU/g. The maxium reductions of S. Typhimurium and B. cereus were 0.95, 1.23 $log_{10}$ CFU/g after treatment with EW combined with 0.5% acetic acid and ultrasound simultaneously. The results suggest that the treatment of EW combined with 0.5% acetic acid and ultrasound increased pathogens reduction compared to individual treatment.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.35-44
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• 1987

Differing in water conditions, the dry matter weight per plant was highest at 0 cm flooding depth, and was decreased at above 2 cm flooding depths. The shoot and spikes per pot developed best at flooding depths of 0 and 2 cm, but worst at -5cm or above 4cm flooding depths. The dry matter weight of shoots was linearly increased, but the weight of roots was sharply decreased according to high temperature after flower initation. The shoots and spikes per pot developed more effectively at 25$^{\circ}C$ than at 35 or 15$^{\circ}C$. The number of shoot and spike per pot were decreased according to higher shading. The effects of shading of 25-45% were not significantly small. The natural white and yellow spectra were the most effective to increase dry matter weight, shoots and spikes per pot. The dry matter weights of shoot and root per plant were not significantly different among at: 50 and 75% clay. The number of shoots were best and continuously increased at 75% clay, and the increments at 0 and 100% clays showed the lag period at early stage. The pattern of spikes was similar to shoots with less difference in various clay composition. The dry matter weight per plant in paddy field and upland field was basically similar. The numbers of shoot and spike were increased in response to increased fertilizer levels up to 20Kg per 10a of each component.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.4
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• pp.317-324
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• 2015

GNSS was firstly proposed for application in weather forecasting in the mid-1980s. It has continued to demonstrate the practical uses in GNSS meteorology, and other relevant researches are currently being conducted. Precipitable Water Vapor (PWV), calculated based on the GNSS signal delays due to the troposphere of the Earth, represents the amount of the water vapor in the atmosphere, and it is therefore widely used in the analysis of various weather phenomena such as monitoring of weather conditions and climate change detection. In this study we calculated the PWV through the meteorological information from an Automatic Weather Station (AWS) as well as GNSS data processing of a Continuously Operating Reference Station (CORS) in order to analyze the heavy snowfall of the Ulsan area in early 2014. Song’s model was adopted for the weighted mean temperature model (T_m), which is the most important parameter in the calculation of PWV. The study period is a total of 56 days (February 2013 and 2014). The average PWV of February 2014 was determined to be 11.29 mm, which is 11.34% lower than that of the heavy snowfall period. The average PWV of February 2013 was determined to be 10.34 mm, which is 8.41% lower than that of not the heavy snowfall period. In addition, certain meteorological factors obtained from AWS were compared as well, resulting in a very low correlation of 0.29 with the saturated vapor pressure calculated using the empirical formula of Magnus. The behavioral pattern of PWV has a tendency to change depending on the precipitation type, specifically, snow or rain. It was identified that the PWV showed a sudden increase and a subsequent rapid drop about 6.5 hours before precipitation. It can be concluded that the pattern analysis of GNSS PWV is an effective method to analyze the precursor phenomenon of precipitation.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.35-47
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• 2018

A edible mushroom, Clitocybe maxima (Lentinus giganteusis) commercially cultivated in China and Taiwan. However, the researches of cultivation and cultural characteristics were not reported in Korea. In this study, we conducted on cultural characteristics and artificial cultivation of C. maxima. Six isolates were collected from China(3 isolates, commercial strain), Taiwan(1 isolate, commercial strain) and Korea(2 isolates, wild type). C. maxima and L. giganteus collected in China and Taiwan, respectively, are the same in China and are estimated to be of the same species as cultured characteristics. The mycelial growth of the collected strains was not significantly different in agar medium but it showed the best growth in YPMG in liquid culture. Optimum temperature for mycelial growth and induction of fruit body were 25℃ and 30℃, respectively. In order to artificial cultivation of C. maxima, cultural characteristics and artificial cultivation were carried out using agricultural by-products and forestry by-products materials. Mycelial growth was suitable in rice straw, cottonwood sawdust, corncob and rice seed medium, and it was selected as a cultivation medium. The suitable medium for artificial cultivation of C. maxima was selected to mixed medium 2(compounding ratio(v/v): 55% of hardwood sawdust, 5% of cottonseed pellets, 10% of cottonseed, 15% of beet pulp, 15% of swollen rice husks). It took about 30 days to be able to harvest, it was faster than oyster mushrooms. The cultivation period was about 30days. A isolate, CMA-002 was not initiation to fruit body primordiuma on the used cultivation substrate. Other 5 isolates were initiate and development to fruit body on the substrate used in this study. The strain CMA-003 was initiated to be fruiting body by 8~10 days after induction of fruiting body in all of the substrates. Isolate CMA-003 was generate to a bundle fruit body. Other isolates, however, were form fruit body individually. The CMA-003 strain was likely highly recommendable strains for farming. The optimum conditions for the induction and growth of C. maxima fruit body were 25~30℃, 8 hr illumination per day with white fluorescent lamp, 90~95% relative humidity, and 1,500 ppm of CO₂ concentration in a cultivation room.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.484-491
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• 2005

Quantitative microbial risk assessment (QMRA) analyzes potential hazard of microorganisms on public health and offers structured approach to assess risks associated with microorganisms in foods. This paper addresses specific risk management questions associated with Staphylococcus aureus in kimbab and improvement and dissemination of QMRA methodology, QMRA model was developed by constructing four nodes from retail to table pathway. Predictive microbial growth model and survey data were combined with probabilistic modeling to simulate levels of S. aureus in kimbab at time of consumption, Due to lack of dose-response models, final level of S. aureus in kimbeb was used as proxy for potential hazard level, based on which possibility of contamination over this level and consumption level of S. aureus through kimbab were estimated as 30.7% and 3.67 log cfu/g, respectively. Regression sensitivity results showed time-temperature during storage at selling was the most significant factor. These results suggested temperature control under $10^{\circ}C$ was critical control point for kimbab production to prevent growth of S. aureus and showed QMRA was useful for evaluation of factors influencing potential risk and could be applied directly to risk management.