• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5B
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• pp.487-495
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• 2010

Soil moisture is a crucial factor in hydrological system which influences runoff, energy balance, evaporation, and atmosphere. United States National Aeronautic and Space Administration (NASA) and Department of Agriculture (USDA) have established Soil Moisture Experiment (SMEX) since 2002 for the global observations. SMEX provides useful data for the hydrological science including soil moisture and hydrometeorological variables. The purpose of this study is to investigate the relationship between remotely sensed soil moisture data from aircraft and satellite and ground based experiment. C-band of Polarimetric Scanning Radiometer (PSR) that observed the brightness temperature provides soil moisture data using a retrieval algorithm. It was compared with the In-situ data for 2-30 cm depth at four sites. The most significant depth is 2-10 cm from the correlation analysis. Most of the sites, two data are similar to the mean of data at 10 cm and the median at 7 cm and 10 cm at the 10% significant level using the Rank Sum test and t-test. In general, soil moisture data using the C-band of the PSR was established to fit the Normal, Log-normal and Gumbel distribution. Soil moisture data using the aircraft and satellites will be used in hydrological science as fundamental data. Especially, the C-band of PSR will be used to prove soil moisture at 7-10 cm depths.

• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.103-104
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• 2004

This paper discuss some results of observed changes of meteorological elements as temperature, precipitation and some extreme indexes in Mongolia. Mongolia is one of the largest landlocked countries in the world. The climate is characterized by a long lasting cold winter, dry and hot summer, low precipitation, high temperature fluctuation and relatively high number of sunny days per year. During last 60 years the annual mean air temperature has risen $1.66^{\circ}C$. Intensive warming of > $2^{\circ}C$ was observed at higher altitudes of high mountains when warming of < $1^{\circ}C$ was observed the Domod steppe and the Gobi Desert. Heat Wave Duration have statistically significant risen trend with increaded number of days by 8-18 at significance level of 95-99.9% depending on geography and Cold Wave Duration have shortened by 13.3 days significance level of 95-99%. In general, by the amount of precipitation, Mongolia falls in semi-arid and arid region. It is 300-350 mm in the high mountain regions while it is only 50-150 mm in Gobi Desert regions. The changes of annual precipitation have very localized character i.e.decreasing at one site and increasing at a sit nearby. Annual precipitation decreased by 30-90 mm in the northern-central region and increased by 2-60 mm in the western and eastern region. The magnitude of alteration changes in precipitation regardless increasing or decreasing is 5-25%. A trends, significant at the level of 90%, found where changes are more than 40 mm or more than 15% of annual mean value. Moreover, the soil moisture resources was decreased in the last 40 years. Specially, moisture contents of the top soil have decreased 2 times(N. Natsagsuren, 2002). Months of June and July in Mongolia is the year that moisture is not inhibiting vegetation growth. Unfortunately, its also found that moisture in this time tends to decrease. Increased temperature, decreased precipitation and soil moisture are most likely resulted in occurences of more intense drought spells that have taken place during the recent years. Intimately, these changes have considerable impact on livestock in Mongolia.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.296-313
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• 1982

At a time when world population and food supply are in a delicate balance, it is essential that we look at factors to improve this balance. We can alter the environment to better fit the plant's needs, or we can alter the plant to better fit the environment. Improved technology has allowed us to increase the yield level. For moderately detrimental weather events technology has generally decreased the yield variation, yet for major weather disasters the variation has increased. We have raised the upper level, but zero is still the bottom level. As we concentrate the production of particular crops into limited areas where the environment is closest to optimum, we may be increasing the risk of a major weather related disaster. We need to evaluate the degree of variability of different crops, and how weather and technology can interact to affect it. The natural limits of crop production are imposed by important ecological factors. Production is a function of the climate, the soil, and the crop and all activities related to them. In looking at the environment of a crop we must recognize these are individuals, populations and ecosystems. Under intensive agriculture we try to limit the competition to one desired species. The environment is made up of a complex of factors; radiation, moisture, temperature and wind, among others. Plant response to the environment is due to the interaction of all of these factors, yet in attempting to understand them we often examine each factor individually. Variation in crop yields is primarily a function of limiting environmental parameters. Various weather parameters will be discussed, with emphasis placed on how they impact on crop production. Although solar radiation is a driving force in crop production, it often shows little relationship to yield variation. Water may enter into crop production as both a limiting and excessive factor. The effects of moisture deficiency have received much more attention than moisture excess. In many areas of the world, a very significant portion of yield variation is due to variation in the moisture factor. Temperature imposes limits on where crops can be grown, and the type of crop that can be grown in an area. High temperature effects are often combined with deficient moisture effects. Cool temperatures determine the limits in which crops can be grown. Growing degree units, or heat accumulations, have often been used as a means of explaining many temperature effects. Methods for explaining chilling effects are more limited.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.26 no.1
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• pp.15-29
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• 1998

The numerical simulation of heavy precipitation event occurred in the central Korean Peninsula on July 26-28, 1996 was performed using the fine mesh model. ARPS (Advanced Regional Prediction System) developed by the CAPS (Center for Analysis and Prediction of Storms). Usually, the heavy rainfalls occurred at late July in the Korean Peninsula were difficult to predict, and showed very strong rainfall intensity. As results, they caused a great loss of life and property. As it usual, this case was unsuccessful to predict the location of rain band and the precipitation intensity with the coarse-mesh model. The same case was, however, simulated well with fine-mesh storm-scale model, ARPS. Moisture band at 850 hPa appeared along the Changma Front in the area of China through central Korea passed Yellow Sea. Also the low-level jet at 700 hPa existed in the Yellow Sea through central Korea and they together offered favorable condition to induce heavy rainfall in that area. The convective activities developed to a meso-scale convective system were observed at near the Yangtze River and moved to the central Korean Peninsula. Furthermore, the intrusion of warm and moist air, origninated from typhoon, into the Asia Continent might result in heavy rainfall formation through redistribution of moisture and heat. In the vertical circulation, the heavy rainfall was formed between the upper- and low-level jets, especially, the entrance region of the upper-level jet above the exit the region of the low-level jet. The low level convergence, the upper level divergence and the strong vertical wind were organized to the very north of the low level jet and concentrated on tens to hundreds km horizontal distance. These result represent the upper- and low-level jets are one of the most important reasons on the formation of heavy precipitation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.6
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• pp.1269-1276
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• 2015

The methodology of utilizing Intensity-Duration-flood Quantity (IDQ) curve for flood alert and warning was introduced and its performance was evaluated. For this purpose the lumped parameter model was calibrated and validated for gauged basin data set and the index precipitation equivalent to alert and warning flood was estimated. The index precipitation and IDQ curves associated by three different Antecedant Moisture Conditions (AMCs) are made provision for various possible flood scenarios. The test basin is Wonju-cheon basin ($94.4km^2$) located in Gangwon province, Korea. The IDQ curves corresponding to alert (50% of design flood level) and warning (70% of design flood level) level was estimated using the Clark unit hydrograph based lumped parameter model. The performance evaluation showed 0.704 of POD (Probability of Detection), 0.136 of FAR (False Alarm Ratio), and 0.633 of CSI (Critical Success Index), which is improved from the result of IDQ with single fixed AMC.

• Atmosphere
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• v.20 no.2
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• pp.111-130
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• 2010

An uncertainty assessment for precipitation datasets simulated by Atmosphere-Ocean Coupled General Circulation Model (AOGCM) is conducted to provide reliable climate scenario over East Asia. Most of results overestimate precipitation compared to the observational data (wet bias) in spring-fall-winter, while they underestimate precipitation (dry bias) in summer in East Asia. Higher spatial resolution model shows better performances in simulation of precipitation. To assess the uncertainty of spatiotemporal precipitation in East Asia, the cyclostationary empirical orthogonal function (CSEOF) analysis is applied. An annual cycle of precipitation obtained from the CSEOF analysis accounts for the biggest variability in its total variability. A comparison between annual cycles of observed and modeled precipitation anomalies shows distinct differences: 1) positive precipitation anomalies of the multi-model ensemble (MME) for 20 models (thereafter MME20) in summer locate toward the north compared to the observational data so that it cannot explain summer monsoon rainfalls across Korea and Japan. 2) The onset of summer monsoon in MME20 in Korean peninsula starts earlier than observed one. These differences show the uncertainty of modeled precipitation. Also the comparison provides the criteria of annual cycle and correlation between modeled and observational data which helps to select best models and generate a new MME, which is better than the MME20. The spatiotemporal deviation of precipitation is significantly associated with lower-level circulations. In particular, lower-level moisture transports from the warm pool of the western Pacific and corresponding moisture convergence significantly are strongly associated with summer rainfalls. These lower-level circulations physically consistent with precipitation give insight into description of the reason in the monsoon of East Asia why behaviors of individually modeled precipitation differ from that of observation.

• Korean journal of food and cookery science
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• v.20 no.5
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• pp.453-461
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• 2004

The purpose of this study was to investigate the instrumental and sensorycharacteristics of Noralbyung made from rice flour and glutinous rice flour containing 1, 2, or 3% of ginger powder. The result of sensory evaluation showed that Noralbyung containing 252g rice flour, 45g (15%) glutinous rice flour, 3g (1%) ginger powder, 3g cinnamon powder, 55ml honey, 15ml water, and 3g (1%) salt had high overall acceptability and chewiness preference. From textural analysis, springinessand gumminess were increased by adding ginger powder. The Hunter color a-, L- and b-values of Noralbyung were all decreased by increasing the level of ginger powder. The moisture content (%) was higher in Noralbyung with sugar than honey. With increasing ginger powder content, the moisture content (%) of Noralbyung was decreased. From these test result, the most desirable recipe for Noralbyung was 252g rice flour, 45g (15%) glutinous rice flour, 3g (1%) ginger powder, 3g cinnamon powder, 55ml honey, 15ml water, and 3g (1%) salt. The moisture content was 37.72%.

• Korean journal of food and cookery science
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• v.25 no.5
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• pp.593-599
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• 2009

This study was conducted to evaluate the quality characteristics of Dureup Sulgidduk samples to different amounts of Aralia elata leaf powder. Overall the samples contained 3.73% moisture, 27.12% crude protein, 1.73% crude fat, 8.06% crude ash and 11.68% crude fiber[ED highlight - very confusing, please clarify which samples(e.g. containing which amount of powder), also, should the moisture be 37. something? It dose not fall within the range in the next sentence. Furthermore, the percentages do not add up to 100, please clarify]. The moisture levels of the samples ranged from 37.72 to 40.45%, with samples containing 0% Aralia elata leaf powder having the highest moisture level. The color L-values decreased, while the a-value increased and the b-value did not differ in response to the addition of Aralia elata powder. The texture and hardness also decreased with increasing Aralia elata leaf powder content,-; however, these values increased in all samples over three days of storage. Finally, samples containing 4% Aralia elata powder received the highest cores for color, flavor, sweetness, softness and overall-acceptability.

• The Korean Journal of Ecology
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• v.23 no.6
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• pp.439-444
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• 2000

Forest vegetation in Mt. Jangan County Park, Jeonlabuk-Do, Korea, was investigated by classification and ordination methods. By the cluster analysis (classification) method, nine groups were recognized as follows : Quercus serrata community, Quercus serrata- Carpinus laxiflora community, Cornus controversa community, Fraxinus mandshurica community, Carpinus laxiflora community, Quereus variabilis community, Quercus mongolica - Sasa borealis community. Quercus mongolica - Symplocos chinensis for. pilosa community and Quercus mongolica - Rhododendron schlippenbachii community. These groups showed differences in species composition and environmental characteristics, but Quercus mongolica - Sasa borealis community, Quercus mongolica - Symplocos chinensis for. pilosa community and Quercus mongolica - Rhododendron schlippenbachii community among them showed very similar floristic composition to each other. The interrelationship between the floristic composition of the vegetation and environmental factors was analysed by principal component analysis (PCA). Quercus mongolica community was distributed at a high altitude (900～1200 m above sea level). Fraxinus mandshurica community and Cornus controversa community were differentiated from the other communities with high contents of soil moisture and pH. On the other hand, Carpinus laxiflora community and Quercus variabilis community were distributed at places with adequate levels of soil moisture, soil organic matter. and at low altitude. In this study, the altitude and soil moisture were the main factors determining the forest vegetation. They were strongly correlated with the dominant compositional gradient at the localities examined.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.107-112
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• 2004

Texture hardening of Yackwa during storage is the major quality deterioration of Yackwa. In this study the effects of gellan gum and xanthan gum on texture hardening of Yackwa during storage were studied. Instrumental hardness and sensory evaluation results showed that addition of 0.05 % and 0.1 % of gellan gum or 0.1 % and 0.5 % of xanthan gum significantly decreased the hardness of Yackwa by 32 ∼ 63 % after 4 weeks of storage. Retardation of texture hardening was obtained even at the 0.05 % level of gellan gum, indicating that gellan gum was a more potent texture modifier for Yackwa than xanthan gum. Correlation analysis between moisture content and hardness of Yackwa showed that there was high correlation between moisture content and hardness of Yackwa after 4 weeks storage ($r^2$=-0.998), regardless of the initial moisture content. These results suggest that retardation of texture hardening during storage is primarily related to moisture retention of Yackwa during storage.