• Journal of the Korean earth science society
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• v.31 no.4
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• pp.313-321
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• 2010

The landform of the study area is defined as a small-scale alluvial plain in the valley bottom adjacent to the coast. By the aggradation of alluvial materials, this valley bottom plain was formed in dissected parts of low hills. For the purpose of reconstructing the palaeo climate environment in this study, $\delta^{13}C$ analysis and soil organic carbon analysis are therefore employed. Main results of this study are as follows: Section I: the period of $6,600{\pm}60yr$ B.P.$-5,350{\pm}60yr$B.P. was mostly in warm and humid climate environment. A little changes of the humid environment are detected as subdry (or sub-humid)${\rightarrow}$humid in terms of the dryness and wetness. Section II: the period of $5,350{\pm}60yr$ B.P.-2,200 yr B.P. was in warm and humid climate environment, which is similar to the present. However, The sediments between $4,720{\pm}60yr$ B.P. and $4,210{\pm}50 yr$ B.P. experienced the most humid climate environment of all studied sedimentary layers. After $4,210{\pm}50 yr$ B.P., the environment started to change from the humid to the sub-humid (or sub-dry) climate. Section III: the period of 2,200 yr B.P.$-210{\pm}60 yr$ B.P. was distinguish from previous two sections as the environmental changes to sub-humid (or sub-dry) climate was apparent.

• Journal of Environmental Science International
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• v.20 no.2
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• pp.251-260
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• 2011

$TiO_2$- and $SiO_2$-supported $Co_3O_4$, Pt and $Co_3O_4$-Pt catalysts have been studied for CO and $C_3H_8$ oxidations at temperatures less than $250^{\circ}C$ which is a lower limit of light-off temperatures to oxidize them during emission test cycles of gasoline-fueled automotives with TWCs (three-way catalytic converters) consisting mainly of Pt, Pd and Rh. All the catalysts after appropriate activation such as calcination at $350^{\circ}C$ and reduction at $400^{\circ}C$ exhibited significant dependence on both their preparation techniques and supports upon CO oxidation at chosen temperatures. A Pt/$TiO_2$ catalyst prepared by using an ion-exchange method (IE) has much better activity for such CO oxidation because of smaller Pt nanoparticles, compared to a supported Pt obtained via an incipient wetness (IW). Supported $Co_3O_4$-only catalysts are very active for CO oxidation even at $100^{\circ}C$, but the use of $TiO_2$ as a support and the IW technique give the best performances. These effects on supports and preparation methods were indicated for $Co_3O_4$-Pt catalysts. Based on activity profiles of CO oxidation at $100^{\circ}C$ over a physical mixture of supported Pt and $Co_3O_4$ after activation under different conditions, and typical light-off temperatures of CO and unburned hydrocarbons in common TWCs as tested for $C_3H_8$ oxidation at $250^{\circ}C$ with a Pt-exchanged $SiO_2$ catalyst, this study may offer an useful approach to substitute $Co_3O_4$ for a part of platinum group metals, particularly Pt, thereby lowering the usage of the precious metals.

• Journal of Korean Society for Geospatial Information Science
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• v.25 no.1
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• pp.19-27
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• 2017

This research was aimed to analyze landslide susceptibility and compare the prediction accuracy using ensemble frequency ratio (FR) and logistic regression at the Inje area, Korea. The landslide locations were identified with the before and after aerial photographs of landslide occurrence that were randomly selected for training (70%) and validation (30%). The total twelve landslide-related factors were elevation, slope, aspect, distance to drainage, topographic wetness index, stream power index, soil texture, soil sickness, timber age, timber diameter, timber density, and timber type. The spatial relationship between landslide occurrence and landslide-related factors was analyzed using FR and ensemble model. The produced LSI maps were validated and compared using relative operating characteristics (ROC) curve. The prediction accuracy of produced ensemble LSI map was about 2% higher than FR LSI map. The LSI map produced in this research could be used to establish land use planning and mitigate the damages caused by disaster.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.433-437
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• 2013

Electrical discharge plasma created in a multi-channel porous ceramic membrane-supported catalyst was applied to the decomposition of a volatile organic compound (VOC). For the purpose of improving the oxidation capability, the ceramic membrane used as a low-pressure drop catalyst support was loaded with zinc oxide photocatalyst by the incipient wetness impregnation method. Alternating current-driven discharge plasma was created inside the porous ceramic membrane to produce reactive species such as radicals, ozone, ions and excited molecules available for the decomposition of VOC. As the voltage supplied to the reactor increased, the plasma discharge gradually propagated in the radial direction, creating an uniform plasma in the entire ceramic membrane above a certain voltage. Ethylene was used as a model VOC. The ethylene decomposition efficiency was examined with experimental variables such as the specific energy density, inlet ethylene concentration and zinc oxide loading. When compared at the identical energy density, the decomposition efficiency obtained with the zinc oxide-loaded ceramic membrane was substantially higher than that of the bare membrane case. Both nitrogen and oxygen played an important role in initiating the decomposition of ethylene. The rate of the decomposition is governed by the quantity of reactive species generated by the plasma, and a strong dependence of the decomposition efficiency on the initial concentration was observed.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.4
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• pp.400-411
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• 1989

Moisture related properties of fabrics in dynamic modes are considered to be important in the judgement of the subjective comfort characteristics of clothing fabrics. In the current study, an attempt to improve the cobaltous chloride test method was made which has been known as a convenient screening test for dynamic surface wetness. The color changes of cobaltous chloride treated fabrics on the simulated sweating skin were calibrated against standard color strips. The standard color strips were made of all typs of test fabrics and installed inside of the test tubes containing a series of saturated salt solutions, which gives more quantitative informations on dynamic moisture transfer Influences of fiber types and finishes on dynamic moisture transfer in textiles were studied using a single layer of fabric samples. Fiber types included $100\%$ cotton, C/P 50/50, C/P 35/65. Durable press and soil release finished cotton and C/P 50/50 fabrics were also included. There were significant fiber effects on the dynamic moisture transfer. The order of time taken to reach to the specified $\%$ RH was C/P 35/65$100\%$ cotton fabrics. It was possible to detect significant finish effects by increasing the concentrations of cobaltous chloride solutions. The order of time taken to reach to the specified $\%$ R.H was durable press$100\%$ cotton, C/P 50/50, C/P 35/65 and $100\%$ PET were placed at the inner side of the outer layer and tested. It was shown that cobaltous chloride treated $100\%$ cotton fabirc was easier to detect color changes than C/P blend fabic in the double layer experiments. By placing test sample under the cobaltous chloride treated cotton fabrics, it was able to detect the differences among the test samples, some of which were known to be difficult in padding with cobaltous chloride solutions. Besides, the double layer method would provide with the broader application of the cobaltous chloride method in !uture, since it is possible to test the dynamic moisture transfer of clothing as worn.

• Research in Plant Disease
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• v.8 no.4
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• pp.199-206
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• 2002

It was investigated on the relationship of the rice blast epidemics and the real-time meteorological factors, at the experimental paddy field in 1997. Weather factors(temperature, relative humidity, irradiation, precipitation, the direction of wind, wind speed, soil temperature and leaf-wetness, etc) were measured by using the automated weather station. The most influenced weather factor to blast epidemics, was the average max-temp($R^2$= 0.95) during 10 days before leaf blast epidemics, while the least thing was wind speed($R^2$= 0.24). The most potential weather factors correlated with the blast epidemics were T-ave(average temperature), T-max(maximum temperature), RH(Relative Humidity) and RD(Relative Humidity > 90% hrs). A statistics model(the regression equation) of the blast epidemics with the potential weather factors, was established as tallows ; Y = -3410.91 - 23.91 $\times$ T-ave ＋ 28.56 $\times$ T-max ＋ 41.0 $\times$ RH - 3.75 $\times$ RD, ($R^2$= 0.99). (T-ave >= 19$^{\circ}C$, T-max - T-ave >= 5.2$^{\circ}C$ and RH% >= 90.4%). According to the fitness test($\chi$$^2$) of the model, the observed blast disease severity was quite close to those expected.

• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.210-216
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• 1987

A computer program written to predict blast occurrence based on micro climatic events was developed and tested as an on-site microcomputer in field plots in 1984 and 1985. A microcomputer unit operating on alkaline batteries; continuously monitored air temperature, leaf wetness, and relative humidity; interpreted the microclimate information in relation to rice blast development and displayed daily values (0-8) of blast units of severity (BUS). Cumulative daily BUS values (CBUS) were highly correlated with blast development on the two susceptible cultivars, M-201 and Brazos grown in field plots. When CBUS values were used to predict the logit of disease proportions, the average coefficients of determination $(R^2)$ between these two factors were 71 to $91\%$, depending on cultivar and year. This was a significant improvement when compared to 61 to $79\%$ when days were used as a predictor of logit disease severity. The ability of CBUS to predict logit disease severity was slightly less with Brazos than M-201. This is significant inasmuch as Brazos showed field resistance at mid-sea­son. The results in this study indicate that the model has the potential for future use and that the model could be improved by incorporating other variables associated with host plants and pathogen races in addition to the key environmental variables.

• Fashion & Textile Research Journal
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• v.7 no.3
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• pp.321-326
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• 2005

The purpose of this study was to investigate the effect of body fat on energy metabolic response and subjective sensations under the hot environment. Fifteen female university students volunteered as subjects. We organized subjects into three groups: low body fat group(group L : less than 20% of body fat), medium body fat group(group M : 20%~30% of body fat) and high body fat group(group H: more than 30% of body fat). The experiment was conducted with $32^{\circ}C$, 60%RH. The subjects repeated 'Exercise' and 'Rest' period. The results of this study are as follows ; The oxygen uptake value of AM is higher than PM. The value of group H is the highest in three fat groups. But it showed group L is the highest in oxygen uptake per weight. %body fat is the lower, oxygen uptake is the higher. In Calorie, group L has higher value in AM in than in PM. In M group and group H, a value of PM is higher than AM. In group H, difference of AM and PM is the highest. From a view point of three groups, a value of group H is the highest. This support that calorie increases as oxygen uptake increase. The heart rate values of group L and group H are the higher in AM than in PM. This support that heart rate was relation to oxygen uptake. In all three groups, the value of blood pressure is higher in AM than in PM. Subjective sensations of temperature sensation, thermal comfort, and wetness sensation are higher in Am than in Pm. This explains that subject sensations are similar to experimental data, such as oxygen uptake, heart rate, blood pressure. In oxygen uptake, heart rate and blood pressure, general tend to showed higher AM than PM. This showed that heart rate, oxygen uptake increase in AM, as blood pressure increase, too. From a view point of %body fat, group H is higher than the others in oxygen uptake, heart rate and blood pressure.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.37-44
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• 1997

The Purpose of this study was to evaluate the effect of cooking methods and reheating on texture characteristics of sausage. Sausage samples were cooked(microwaving, gas-broiling and frying), reheated on day 3 and 6 after refrigeration and put to evaluation of sensory and texture characteristics. The results of sensory evaluation showed that hardness, salty taste, rancid flavor and after-taste were increased but wetness and chewiness were decreased by reheating after refrigeration. Overall acceptability was the highest when the samples were gas broiled and reheated on day 3 after refrigeration. As for the estimation of texture changes by rheometer, hardness, cohesiveness, elasticity, gum-miness and chewiness tended to increase by reheating after refrigeration. Hardness, cohesiveness, gumminess and chewiness were the highest when the samples were gas-broiled and reheated on day 3 after refrigeration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1192-1201
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• 2016

This study was conducted to investigate sensory characteristics and consumer acceptance of sliced raw fish. The two most popular varieties in Korea, flounder and rockfish, were used. Samples of each variety were prepared as follows to create consistent perceptible sensory differences: 'fresh' (consumed within 2 h after sacrifice), 'aged' (stored at $1^{\circ}C$ for 24 h), 'frozen' (frozen at $-16^{\circ}C$ for 23 h then thawed at $23.5^{\circ}C$for 1 h), and 'immersed' (immersed in sterilized water at $1^{\circ}C$ for 24 h). Sensory profiles of samples were determined through quantitative descriptive analysis using 10 trained panelists. Consumer acceptance test was conducted using 47 consumers. Analyses of variance were conducted to test significance of differences in sensory profiles and hedonic ratings among samples. Consumers were clustered according to their overall liking scores, and their preference patterns were cross-checked with sensory profiles. For both fish varieties, 'fresh' was characterized by stronger hardness, cohesiveness, springiness, cartilage-like texture (applied to only rockfish), and fishy flavor, whereas 'frozen' and 'immersed' were distinguished from other samples for their stronger wetness, juiciness, and fresh fish flavor than those of other samples. 'Aged' was significantly less hard, cohesive, and springy than 'fresh' as well as less juicy and wet than 'frozen' and 'immersed'. Consumers significantly preferred 'fresh' flounder and rockfish to others for their strong cohesiveness and springiness, indicating textural attributes were main factors affecting consumer preferences. However, for both flounder and rockfish, 40~50% of respondents preferred 'frozen' and 'immersed' to 'fresh' for their tenderness and fresh fish flavor. For this group of consumers, flavor liking had a greater effect on overall preference than texture preference. The result suggests that cohesive and springy textures and fresh fish flavor are major drivers of preferences for raw fish slices, but their relative importance and optimal levels varied across individual consumers.