• Journal of the Korean earth science society
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• v.39 no.2
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• pp.139-153
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• 2018

The sea surface wind field has long been obtained from satellite scatterometers or passive microwave radiometers. However, the importance of satellite altimeter-derived wind speed has seldom been addressed because of the outstanding capability of the scatterometers. Satellite altimeter requires the accurate wind speed data, measured simultaneously with sea surface height observations, to enhance the accuracy of sea surface height through the correction of sea state bias. This study validates the wind speeds from the satellite altimeters (GFO, Jason-1, Envisat, Jason-2, Cryosat-2, SARAL) and analyzes characteristics of errors. In total, 1504 matchup points were produced using the wind speed data of Ieodo Ocean Research Station (IORS) and of Korea Meteorological Administration (KMA) buoys at Marado and Oeyeondo stations for 10 years from December 2007 to May 2016. The altimeter wind speed showed a root mean square error (RMSE) of about $1.59m\;s^{-1}$ and a negative bias of $-0.35m\;s^{-1}$ with respect to the in-situ wind speed. Altimeter wind speeds showed characteristic biases that they were higher (lower) than in-situ wind speeds at low (high) wind speed ranges. Some tendency was found that the difference between the maximum and minimum value gradually increased with distance from the buoy stations. For the improvement of the accuracy of altimeter wind speed, an equation for correction was derived based on the characteristics of errors. In addition, the significance of altimeter wind speed on the estimation of sea surface height was addressed by presenting the effect of the corrected wind speeds on the sea state bias values of Jason-1.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.59-66
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• 2020

Recently, cultivation and management technologies have been needed to adapt due to climate change, which is causing abnormal weather conditions. One technique is to increase the utilization of evergreen broad-leaved species with high ornamental value. A total of five treatments were installed (1m×22.5m), including 60g/㎡ and 80g/㎡ using two types mulching material with an overlapping and hole-drilling mulching method and these were compared to un-mulching treatment a total of planted 92㎡ attheWol-aTestSiteForestattheForestforBiomaterialsResearchCenterinJinju-si, Gyeongsangnam-dofor 10monthsusing3-years-oldQuercusglaucaThunb. In comparison with the control site, the 60g/㎡ overlapping method was about 1.9 times higher than the root collar diameter, but there was no statistical significance between the treatments. Healthy seedlings were found to meet these conditions due to high biomass values and below and T/R ratios of 3.0 or lower and H/D ratios of 7.0 or lower. Comparing the values of LWR, SWR, and RWR, which can be evaluated for seedling due to the mulching treatments, as compared to the control, the growth of the ground areas including leaves and stems was enhanced, but the growth of the underground areas containing roots tended to have high control values. Based on this, the SQI value, which can be evaluated for the comprehensive quality of seedlings, was found to be significantly different between the control site and the mulching treatment sites, confirming that the growth and growth improvement effects were achieved with mulching treatments. The chlorophyll content analysis showed that there was a significant difference from the control site, and it was judged that weed generation in the control acted as an environmental stress, causing a decrease in chlorophyll content. It was found that the overlapping 80g/㎡ of polypropylene mulching material generated about 4 times fewer weeds than the control, and the manpower required for the mulching test field and weeding were equal at 3.3 people/100㎡/1 day. Mulching treatments have demonstrated a significant difference in the promotion of growth and quality of the seedlings and are judged as an alternative that can reduce the economic burden incurred by the purchase of the supplies and the manpower required to weed forestry plantations.

• Culinary science and hospitality research
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• v.23 no.2
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• pp.64-73
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• 2017

Although 24-hour recalls (24HR) capture detailed information on a person's food intake, this method suffers from difficulties in adequately measuring the usual intake of foods that are not consumed daily by most. Therefore, the purpose of this study is to investigate whether frequency of Food Frequency Questionnaire (FFQ) can be utilized in form of covariate when calculating usual intake of episodically-consumed foods and their distributions. Data used in this study was from the Korean National Healthy and Nutrition Examination Survey (KNHANES) 2012~2014 (3 years) and 10,945 subjects participated in this survey who performed both of 24HR and FFQ. In order to analyze the data, amount of intake in each food, which was reported in 24HR was recalculated according to 112 items in FFQ. We first assessed the relationship between FFQ frequency and the amount reported on 24HR. Second, we assessed the relationship between usual portion size of FFQ and the amount reported on 24HR. Our hypothesis was that people who reported high FFQ-reported frequency or FFQ-reported usual portion size would consume larger amounts of that food on 24HR than those with lower frequency or portion size of consumption of a food on the FFQ. For 59 of 112 individual foods (52.2%), there were statistically significant increasing relationships between FFQ frequency and consumption-day intake. Also, 102 of 112 individual foods (90.3%), there were statistically significant increasing relationships between FFQ usual portion size and consumption-day intake. For 10 of 13 food groups (grains, fruits, eggs, pulses, root and tuber crops, milk products, meat, beverage, alcoholic drink, vegetable, seaweeds and others), there were statistically significant increasing relationships between FFQ frequency and consumption-day intake. And there were statistically significant increasing relationships between FFQ usual portion size and consumption-day intake for all food groups. This study confirmed consistent correlation between reported FFQ frequency or usual portion size of food (group) consumption and consumption-day intake on 24HR. Therefore the frequency data may be utilized as important covariate when estimating usual intake of food or food groups.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.2
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• pp.213-230
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• 2008

The aim of this study was to analyze the initial movement and the stress distribution of each tooth and periodontal ligament during the lingual lever-arm retraction of 6 maxillary incisors using FEA. Two kinds of finite element models were produced: 2-properties model (simple model) and 24-properties model (multi model) according to the material property assignment. The subject was an adult male of 23 years old. The DICOM images through the CT of the patient were converted into the 3D image model of a skull using the Mimics (version 10.11, Materialise's interactive Medical Image Control System, Materialise, Belgium). After series of calculating, remeshing, exporting, importing process and volume mesh process was performed, FEA models were produced. FEA models are consisted of maxilla, maxillary central incisor, lateral incisor, canine, periodontal ligaments and lingual traction arm. The boundary conditions fixed the movements of posterior, sagittal and upper part of the model to the directions of X, Y, Z axis respectively. The model was set to be symmetrical to X axis. Through the center of resistance of maxilla complex, a retraction force of 200g was applied horizontally to the occlusal plane. Under this conditions, the initial movements and stress distributions were evaluated by 3D FEA. In the result, the amount of posterior movement was larger in the multi model than in the simple model as well as the amount of vertically rotation. The pattern of the posterior movement in the central incisors and lateral incisors was controlled tipping movement, and the amount was larger than in the canine. But the amount of root movement of the canine was larger than others. The incisor rotated downwardly and the canines upwardly around contact points of lateral incisor and canine in the both models. The values of stress are similar in the both simple and multi model.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.1
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• pp.80-87
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• 2011

Panax ginseng has been used as a traditional medicine for several centuries in Korea. A laboratory experiment using methanol extracts of freeze-dried leaves and roots in the different ages of P. ginseng was conducted to determine the content of phenolics and flavonoids, antioxidant activity and cytotoxicity. The results indicate that the total phenolics level [mg ferulic acid equivalents (FAE) $kg^{-1}$ DW] was higher in leaves (22.0 to 76.3 mg $kg^{-1}$) than roots (19.0 to 28.3 mg $kg^{-1}$) of P. ginseng. The total content of phenolics in roots increased with increase in age of P. ginseng from one to six years. However, the content of phenolics in P. ginseng leaf decreased with the increase in age. Total flavonoid [mg naringin equivalents $kg^{-1}$ DW] was more detected in the leaves (30.3 to 138.6 mg $kg^{-1}$) than in the roots (0.0 to 10.6 mg $kg^{-1}$) of P. ginseng. The total flavonoid level in leaves decreased with increase in age of P. ginseng. The antioxidant potential of the methanol extracts from the plants dose-dependently increased. DPPH free radical scavenging activity was higher in leaves (36.9 to 82.8%) than in roots (14.8 to 39.4%), and in young plants than in old ones. According to 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the methanol extracts from 5 year-root part showed the highest cytotoxicity against Calu-6, followed by 2 year- and 3 year-roots. However, the methanol extracts from 6 year- and 4 year-roots had lower cytotoxicity. Total phenolics content in both leaves and roots was highly correlated with the DPPH radical scavenging ($r^2=0.7366$ to 0.7870) and nitrite scavenging ($r^2=0.5604$ to 0.8794) activities, suggesting that they contribute to the antioxidant properties of the P. ginseng plants.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.174-181
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• 1998

In four citrus grow of Satsuma mandarin (rootstock of trifoliate orange) including two grove of organical management and two groves of conventional management, spores of arbuscular mycorrhizal(AM) fungi were identified and seasonal changes in spore density in soils and AM colonization of citrus roots were investigated. AM colonization in weeds found in the groves were also examined. Three species of Glomus (G.deserticola, G. vesiculiferum, G. rubiforme ) and one unknown species of Acaulospora were observed in all of the groves. Annual mean density of AM fungal spores were in the range of 10,000${\sim}$40,000 per 100g soil with more spores in the organically-managed groves. The least spores were observed in December in all groves, and the most spores in April in the organically-managed groves while in February or April in the conventionally- managed. Annual mean AM colonization more 27% of citrus root were observed in the organically-managed with the high peaks in April and October and the minimum in August, while mean colonization less than 15% in the conventionally-managed with the peak in February and the minimum in different times depending on groves and years. AM colonization corresponded to a sigmoidal curve consisting of a laf phase during winter and a subsequent increase in spring, then succeeded by a maximum, and then a decrease at the end of vegetation. Fungal spore density and AM colonization showed a parallel pattern during the sample period. The seasonality appeared to be related more to the phenology of the plant than to the soil factors. Generally more spore density and AM colonization were found in organically managed groves. AM colonization was not correlated with available P and organic matter content in soil in this field investigation. Among sixteen weed species found in the groves, Astrogalus sinicus of Leguminosae, Portulaca oleracea of Portulacaceae showed high colonization in all groves and they can be considered as a source of inoculumn and host plants for propagation of AM fungi.

• Journal of Korea Water Resources Association
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• v.42 no.11
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• pp.911-920
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• 2009

Virtual water is defined as the volume of water required to produce a commodity or service. The degree of food self-sufficiency is currently about 27 % in South Korea, so that Korea is one of the largest net virtual water import countries for agricultural product, thus it is necessary to estimate suitable virtual water for South Korea. The objective of this paper is to quantify the agricultural virtual water use (AWU) and virtual water content (VWC) using the method suggested by Chapagain and Hoekstra during the period 1991-2007. To calculate the virtual water content, 44 different crop production quantity and harvested area data were collected for 17 years and FAO Penman-Monteith equation was adapted for computing crop consumptive use of water. As the results, AWU has been estimated at 15.1 billion $m^3$ in average showing a tendency to decrease. Rice has the largest share in the AWU, consuming about 10.1 billion $m^3$/yr which is about 75 % of gross AWU, and the VWC is 1600.1 $m^3$/ton for paddy rice. The largest VWCs of crops are oilseed and tuber crop, and the smallest are leaf and root vegetables. The primary crop production VWC can be used for calculating the VWC of various secondary products using the contribution ratio, therefore the results of this study are expected to be used as basic data for national agricultural water footprint.

• Restorative Dentistry and Endodontics
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• v.24 no.4
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• pp.560-569
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• 1999

Blood supply rather than nerve supply implies pulp vitality. To evaluate pulp vitality clinically, electric pulp test and thermal test which are based on sensory nerve response have been used in addition to many auxiliary data such as past dental history, visual inspection, radiographic examination, percussion, palpation and transillumination test. However, reactivity of the nerves to the stimulation is not synonymous with normalcy. Therefore measurement of pulpal blood flow using a laser Doppler flowmeter became a new trial to test the pulp vitality. The purpose of the present study was to evaluate normal pulpal blood flow level of maxillary teeth in adult to provide a guideline in determining the vitality of dental pulp. Pulpal blood flow was measured in maxillary central and lateral incisors, canines, first and second premolars and first molars of seventy nine adults of 22 - 30 years old using a laser Doppler flowmeter (PeriFlux 4001, Perimed Co., Stockholm, Sweden, 780 nm infrared laser, 1mW). For directly-made splints, silicone rubber impressions were taken directly from the mouth. For indirectly-made splints, alginate impressions were taken from the mouth and stone cast were made. After making depressions on the buccal surfaces of the cast teeth to indicate the hole positions, second impressions with vinyl polysyloxane putty were taken from the cast. Holes for the laser probes were made at the putty impressions 4mm above the gingival level. Laser probe (PF416 dental probe, 1.5mm) was inserted in the prepared hole and the splint was set in the mouth. After 10 minutes of patient relaxing, pulpal blood flow was recorded for 5 minutes on each tooth. The recorded flow was saved in the computer and calculated with a software 'Perisoft' version 5.1. Pulpal blood flow was also recorded in six teeth of five individuals with no response to electric pulp test and cold test, with periapical radiolucency, or with history of root canal treatment to compare with nonvital teeth. The difference between the mean flow values of each group of teeth were analyzed using one-way ANOVA and Duncan's Multiple Range test. The results were as follows: 1. The average pulpal blood flow values of all the tested teeth of each location were between 9 - 16 Perfusion Unit. Pulpal blood flow value was highest in maxillary lateral incisors, followed by first premolars, second premolars, canines, central incisors, and then first molars (p<0.01). 2. In six anterior teeth, indirectly-made splint group showed higher pulpal blood flow values than directly-made splint group (p<0.01). In posterior teeth, however, there was no significant flow value difference between directly-made splint group and indirectly-made splint one (p>0.05). 3. Teeth with vital pulps showed higher signal values than teeth with nonvital pulps (p<0.01), and the flow photographs showed heartbeat-synchronous fluctuations and vasomotions, while those were absent in non vital tooth.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.1
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• pp.36-47
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• 2017

In this research, sematic comparative study on formative idea and landscape elements composition was made between Soswaewon which was a remote villa garden in Joseon Dynasty and Canglang Pavilion which was built at a time when Neo-confucianism had been created in Song dynasty. From which the summary was resulted as below: Firstly, Soswaewon was fully devoted to Neo-confucianism among Korean remote villa gardens, Canglang-Pavilion was deeply affiliated with Neo-confucianism the deep-rooted thought. Adding a comment, as a richly historied Chinese private garden it was the best preserved even now and the farmost point from now and approximately 500 years advanced than Soswaewon, moreover Sosunheum the builder belonged to gentry society in Song dynasty. Secondly, Both Soswaewon and Canglang-Pavilion were remarkable thank to nature friendly concept which was deeply rooted in the eremitic thought(隱逸思想). Most of all, it might be interpreted the location of Soswaewon lay down in a mountain, as to be swallow hidden(小隱) but that of Canglang-Pavilion lay down in a city, as to be middle hidden(中隱). Thirdly, approaching with comparative study to gardens' factors implicated in symbolization when naming both Soswaewon and Canglang-Pavilion, neo-confucianism in Song dynasty in which diverse thoughts ranging Confucianism and Buddhism and Taoism had formed ensemble and developed was deeply built in Soswaewon, as to be in consistency to nature and to be a basis for comprehending diverse symbolization factors found in Canglang-Pavilion. Fourthly, given that forms or factors of gardens was tangibly came up with thoughts' variation we surely underwent to comparative study. Through which we could know Soswaewon was made by maximizing use of nature but minimizing addition of artificial things. In other words, it was trial of expressing semantic feature of the site in a way blending natural circumstance and liberal one. One of the representatives, Daebongdae in Soswaewon was a site where the owner's idea came up with. Scenary was recreated and nature was represented in interspace of Canglang-Pavilion with the high wall around the border, for which it renounced the world. To the end, it was understood there was the location characteristic of Canglang-Pavilion which let us look down from mountain and take some time for introspection. It might be said that the cultural root was in common between Korea and China, however it was found there were lots of differences in forms and features of gardens. We were able to interpret that social and cultural background were led to gardens' formation in which individual characteristic of two nations were blended, from which difference was resulted.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.1-7
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• 2001

Total upland area for cultivating the vegetable crops in the Alpine soils of Northeastern South Korea has been extending its limit to meet the increasing demand of vegetable food in recent decades. About 70% of these alpine soils are located in over 7% of the slope and most of vegetable crops have been cultivated intensively without practicing the best management systems. Thus, soil erosion and continuous cropping system have degenerated the soil fertility and shown detrimental effects on water quality. We initiated an intensive and extensive investigation to characterize the fertility problems encountered in these uplands. Objectives of this paper were to characterize the fertility status in the Alpine soils cultivated with vegetable crops for many years and to provide the recommendations for adequate soil management measures including fertilization and erosion control. Soils in general have good drainage with textural classes of loam or sandy loam. Their topographical characteristics tended to lead them to shallow plow layers, and the steepness of the terrain created erosion hazard. Of the soils examined, about 11% of uplands over 30% gradient was found in need of an urgent reforestation. A high content of gravel and firm hardness of soil attributed to inhibit the utilization of farm machinery and plant-root development. The average soil pH 5.6 was slightly low relative to pH 5.70 of the national average. Organic matter content was high compared with 2.0% of national average, but decreased with the prolonged cultivation periods. Available $P_2O_5$ concentration was unusually high due to the consequence of over dose application with chemical and organic fertilizers. Exchangeable cations as Ca, Mg, and K were appeared to be decreased in these regions with prolonging the cultivation periods. There were no significant differences in cation exchange capacity (CEC) and electrical conductivity (EC) among locations. Heavy metal contents were mostly lower than the threshold of danger level designated by Soil Environment Conservation Law of South Korea. Results indicated that a proper countermeasure and the best management practice should be immediately implemented to conserve the top soil and fertility in the Alpine regions.