• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.232-239
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• 2001

Young Jong Grand Bridge is approach traffic road of New Inchon International Airport which covers hub airport function in northeast asia. The total span length of this bridge is $4,420{\cal}m$ and this main bridge type is, the first in the world, Double Deck Self Anchored Suspension Bridge, designed as double deck systems to be arranged by road and railroad. Approach bridges to be connected with main span also are composed double deck steel truss and steel box girder to consider a continuity with this span. Our company erected $1,375{\cal}m$(about 60,000tons) of double deck steel truss bridge type which is composed by 6 traffic lane on upper deck and 4 traffic lane and Double track railroad on lower deck. The original installation method of this bridge was planed to install about 75 meters bridge blocks to use floating crane, after temporary bent was constructed between permanent piers. But this method which had to construct many temporary bents in the sea had the matter that construction periods can become lengthen and construction cost can be risen. To overcome the uncertainty to ensure high qualify of bridge and economic project execution, our company developed new bridge erection method to assure both quality control and economic construction work. The new erection method which was developed by us was one that could transport and install long bridge block, $120{\cal}m$ unit at a time and that temporary bent was not required. We hope that this paper is used as technical data which will erect bridge in the western sea and others marine region.

• Journal of the Korean Society for Railway
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• v.11 no.5
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• pp.441-448
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• 2008

Increasing urban sprawl and climate changes have been causing unexpected high-intensity rainfall events. Thus there are needs to enhance conventional disaster management system for comprehensive actions to secure safety. Therefore long-term and comprehensive flood management plans need to be well established. Recently torrential snowfall are occurring frequently, causing have snow traffic jams on the road. To secure safety and on-time operation of the Bi-modal tram system, well-structured disaster management system capable of analyzing the show pack melt/freezing due to unexpected snowfall are needed. To secure safety of the Bi-modal tram system due to torrential snow-fall, the snow melt simulation capability was investigated. The snow accumulation and snow melt were measured to validate the SWMM snow melt component. It showed that there was a good agreement between measured snow melt data and the simulated ones. Therefore, the Bi-modal tram disaster management system will be able to predict snow melt reasonably well to secure safety of the Bi-modal tram system during the winter. The Bi-modal tram disaster management system can be used to identify top priority area for know removal within the tram route in case of torrential snowfall to secure on-time operation of the tram. Also it can be used for detour route in the tram networks based on the disaster management system prediction.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.2
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• pp.352-362
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• 2015

The purpose of this study was to examine portion sizes and nutritional quality of foods served to children at Community Child Centers (CCCs), July 2014, in Korea. A survey was administered to foodservice employees working at CCCs. Thirty-nine participants completed the self-administered questionnaire regarding CCCs foodservice practices. In the weight test, fifteen volunteers of demonstrated typical portion sizes for $5^{th}$ grade elementary school students. Nutrition knowledge scores were significantly different between foodservice employees with experience taking a foodservice class for one year (6.04 out of 10.0 points) and those without experience (4.58 points). Foodservice employees with experience taking a foodservice class scored significantly higher in performing meal serving practices, e.g., wearing a sanitary cap and apron when serving food, than those without experience. The amount of foods served for children did not meet standard serving sizes; portion sizes of rice, soup, main dish, side dish and kimchi served by foodservice employees were 87.3%, 63.2%, 56.5%, 37.1% and 81.3% of standard serving sizes, respectively. When energy and nutrient intakes from portion sizes were calculated, energy, vitamin A, thiamin, riboflavin and calcium intakes did not meet standards for nutrition control of school meals. However, protein, vitamin C and iron intakes met more than 100.0% of standards. These findings suggest that foodservice employees with experience taking a foodservice class apply their knowledge to foodservice practices. Although portion sizes can influence energy and nutrient intakes in children, the actual portion sizes served by CCCs foodservice employees were inadequate and did not meet standards for serving size and nutrition. Thus, all CCCs foodservice employees need to receive foodservice education and be provided guidelines regarding portion sizes for children.

• Research in Plant Disease
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• v.20 no.4
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• pp.270-274
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• 2014

Division of Forest Diseases & Insect Pests, Korea Forest Research Institute, Seoul 130-712, Korea The objective of this study was to evaluate the virulence of geographically different isolates of oak wilt pathogen, Raffaelea quercus-mongolicae and other Raffaelea species. In this study, mature trees of Quercus mongolica were inoculated with the various isolates of Raffaelea spp. and their virulence was evaluated by measuring the extent of sapwood discoloration resulting from the inoculation. The average length of discolored sapwood in a lateral direction was longest in the trees inoculated with the isolates from Korea (8.69 cm) followed by R. quercivora (7.51 cm) and the other Raffaelea spp. (3.35 cm). The lateral length of discolored sapwood caused by the inoculation with Korean strains varied from 4.71 to 14.90 cm indicating their differences in virulence. The area of discolored sapwood caused by the inoculation with Raffaelea spp. varied from 1.57 to $8.42cm^2$ indicating their differences in virulence. Based on the length and area of the discolored sapwoods, isolated YY and wj43 appeared to have the highest virulence among all the Raffaelea isolates tested. Each of the two isolates was obtained from Gangwon Province and Jeonbuk Province, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.421-427
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• 1995

To know the variation in the growth of the sea urchin, Pseudocentrotus depressus according to their localities, three different populations including the culture populations, the released populations, and the wild populations were investigated using the cluster analysis. For this purpose, pigment banding pattern on the genital plate was used as an age character. The population composed of the same year class was born between September 25th and October 5th every year. The population of 9 to 10 months old had no $r_1,\;whereas\;r_1$, was observed in the population of either 1 year and 10 or 11 months old, and both $r_1,\;and\;r_2$ in the population of either 2 year and 9 or 10 months old. Therefore, $r_1,\;and\;r_2$ radius were regarded as an annual ring. Growth in the culture populations was much better than that In either the released or the wild populations. However, when the cultured populations composed of 8 to 12 mm in test diameter was released to the shove near a culture farm, its growth appeared to be similar to that of the wild Populations. The wide distribution patterns of test diameter measured from the same year class of both the cultured and the wild populations were probably due to either long spawning period or growth differences between individuals. Except Yamaguchi and Cheju populations, the move closely located populations showed the more similar growth pattern. However, the growth of Cheju population appeared to be similar to that of Aba, Mogi, Toishi rather than Kasiwazima although Cheju Island was more closely located with Kasiwazima than other localities. In addition, the population of Yamaguchi, located at the highest latitute, revealed the similar growth pattern to that of Nomozaki, located at the lowest latitute.

• Korean Journal of Community Nutrition
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• v.23 no.4
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• pp.318-332
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• 2018

Objectives: The purpose of this study was to investigate the behavioral modification of obese adults who underwent nutritional and physical activity education. Twenty obese females, aged 20-60 years old, with BMIs (Body Mass Index) >30 or body fat (%) >40 were subjected to this study. Methods: The physical activity education program consisted of doing exercise in a gymnasium together or home exercise. Dietary attitudes and dietary intakes were assessed using weight control, physical activity, and eating habits. The nutrition-exercise educational period was 12 weeks. Results: After the study period, there was significant improvement in physical activity and eating habits score. Furthermore, there was a significant increase in the dietary intakes of fiber, iron, potassium, vitamin A, vitamin $B_6$, and niacin. Blood pressure, blood glucose, and total cholesterol levels showed a tendency to decrease, but there was no significant difference. BMI, fat mass, abdominal circumference, and visceral fat levels were significantly reduced while muscle mass significantly increased. Conclusions: This study suggests that behavioral modification by nutrition and physical activity education with feedback has positive effects on dietary intake and anthropometric biomarkers in obese adults. Therefore, lifestyle interventions of this kind could be recommended as a method for obesity management.

• Korean Journal of Environmental Biology
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• v.26 no.2
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• pp.121-127
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• 2008

As a step toward developing conservation and restoration plans for an endangered species of the Oriental White Stork (Ciconia boyciana), we studied daily foraging behavior and ecology. We released two individuals, male and female, after enclosing study site with a fence and cutting out a part of two or three feathers of primaries. Research was conducted from 16 June to 11 July, 2007 for 25 days at Whawonri, Mewonmyung, Chungbuk province. We investigated diural and daily variation of foraging time budget, diet composition, and habitat selection of the feeding individuals. The storks quadratically invested for foraging time and resting time according to time of day, but no significant variation in the foraging time and resting time appeared daily over 25 days. As a result, the storks mainly used wetland as a foraging site in the center of the study area to that in the edge as well as to other types of habitat. The high usage for wetland in the center did not change over the 25 days while Rice field decreased and Wetland in the edge and Pathway increased. Female invested more time for foraging than male, but the foraging efficiency did not differ between them. We discussed the significance of foraging behavior and habitat selection for management plan.

• Journal of Korea Water Resources Association
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• v.54 no.10
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• pp.769-777
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• 2021

This study investigated the change of the achievement rate of the target water quality conditioned on the occurrence of severe drought, to assess the effects of meteorological drought on the water quality management in the Nakdong River basin. Using three drought indices with difference time scales such as 30-, 60-, 90-day, i.e., SPI30, SPI60, SPI90, and three water quality indicators such as biochemical oxygen demand (BOD), total organic carbon (TOC), and total phosphorus (T-P), we first analyzed the relationship between severe drought occurrence water quality change in mid-sized watersheds, and identified the watersheds in which water quality was highly affected by severe drought. The Bayesian network models were constructed for the watersheds to probabilistically assess the relationship between severe drought and water quality management. Among 22 mid-sized watersheds in the Nakdong River basin, four watersheds, such as #2005, #2018, #2021, and #2022, had high environmental vulnerability to severe drought. In addition, severe drought affected spring and fall water quality in the watershed #2021, summer water quality in the #2005, and winter water quality in the #2022. The causal relationship between drought and water quality management is usufaul in proactive drought management.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.127-142
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• 2024

This study aimed to understand the interrelationships between tree species in plant communities through Plant Social Network (PSN) analysis using a large amount of vegetation data surveyed in an island area belonging to a warm-temperate boreal forest. The Machilus thunbergii, Castanopsis sieboldii, and Ligustrum japonicum, which belong to the canopy layer, Pittosporum tobira and Ardisia japonica, which belong to the shrub layer and Trachelospermum asiaticum and Stauntonia hexaphylla, which belong to the vines, appearing in evergreen broad-leaved climax forest community, showed strong positive association(+) with each other. These tree species had a negative association or no friendly relationship with deciduous broad-leaved species due to the large difference in location environments. Divided into 4 group modularizations in the PSN sociogram, evergreen broad-leaved tree species in Group I and deciduous broad-leaved tree species in Group II showed high centrality and connectivity. It was analyzed that the arrangement of tree species (nodes) and the degree of connection (grouping) of the sociogram can indirectly estimate environmental factors and characteristics of plant communities like DCA. Tree species with high centrality and influence in the PSN included T. asiaticum, Eurya japonica, Lindera obtusiloba, and Styrax japonicus. These tree species are common with a wide range of ecological niches and appear to have the characteristics and survival strategies of opportunistic species that commonly appear in forest gaps and damaged areas. They will play a major role in inter-species interactions and structural and functional changes in plant communities. In the future, long-term research and in-depth discussions are needed to determine how these species actually influence plant community changes through interactions

• Journal of the Korean earth science society
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• v.26 no.5
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• pp.395-403
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• 2005

This study is focused on the relationship between snowfall and the Bowen’s Ratio (sensible heat flux/latent heat flux) through calculation of heat exchange between air and sea for snowfall events in Jeju Island from 1993 to 2003. The four weather stations for this study are located at Jeju, Seoguipo, Seongsanpo and Gosan in Jeju Island. In order to improve the reliability of snowfall forecast, the Bowen’s Ratio for snowfall, which includes influences from the atmosphere such as wind, is compared with the temperature difference between air and sea for snowfall. As a results, in the case for fresh snowfall, the minimum temperature differences between air and sea were 10, 12.3, 11.5, and $14.3^{\circ}C$ at Jeju, Seoguipo, Seongsanpo and Gosan, respectively. The probabilities of fresh snowfall were 26, 29, 13, and $23\%$, respectively, when the temperature differences were higher than the previous values. On the other hand, the minimum Bowen ratios were 0.59, 0.60, 0.65 and 0.65 at Jeju, Seoguipo, Seongsanpo and Gosan, respectively. The probabilities of fresh snowfall were 33, 70, 31 and $58\%$ respectively, when the Bowen ratio is higher than those. The reason for this is because the probability of fresh snowfall with the Bowen ratio was higher than the probability with temperature difference between air and sea. This result occurred because heat exchange by wind increased the probability of snowfall, along with the temperature difference between air and sea, and the Bowen ratio. Therefore, snowfall forecast of Jeju Island is significantly influenced by the sea, whereas forecast with Bowen ratio seems to have higher reliability than that with the temperature difference between air and sea. The data analysis for the ten-year period $(1993\~2002)$ showed that when each fresh snowfall was within 0.0 to 0.9cm, the average Bowen’s ratio was 0.63 to 0.67, and when each fresh snowfall was 1.0 to 4.9 cm, the average Bowen’s ratio was over 0.72. Therefore, fresh snowfall shows a proportional relationship with the Bowen’s ratio during snowfall.