• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.534-539
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• 2018

'Hwawang' is an early maturing and short statured rice cultivar adaptable to the rice-cash crop rotation system that was developed by the rice breeding team of the Department of Southern Crop, National Institute of Crop Science (NICS), Rural Development Administration (RDA), Korea, in 2012. This cultivar was derived from the cross of YR25867 (Hitomebore//YR21247-B-B-B-49-1/Sasanishiki BL4) and YR25866 (Akidagomachi//YR21247-B-B-B-49-1/Sasanishiki BL4) during the 2005/2006 winter season and was fixed as a homozygous line by a doubled haploid breeding system. In the replicated yield trial in 2009, a promising line (YR26253Acp26-1) showed a good phenotype and high yield potential, and so it was selected and designated as 'Milyang256'. The local adaptability test of 'Milyang256' was carried out at three locations from 2010 to 2012. It was named 'Hwawang' and had a high head rice ratio and good eating quality. The culm length of 'Hwawang' averaged 62 cm during the yield trials and was 10 cm shorter than that of 'Keumo'. The number of spikelets per panicle of 'Hwawang' was significantly lower than that of 'Keumo', but the number of tillers per hill was higher. This variety showed resistance to bacterial blight disease but was moderately susceptible to both leaf and neck blast. The milled rice yield of 'Hwawang' was 452 kg/10 a at the late transplanting stage of the local adaptability test. Thus, 'Hwawang' is well adapted to the rice-cash crop rotation system in the southern plain area. (Registration No. 5106)

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.135-153
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• 2021

The demilitarized zone (DMZ) is a border barrier with 248 kilometers in length and about 4 kilometers in width crossing east to west to divide the Korean Peninsula about in half. The boundary at 2 kilometers to the south is called the southern limit line. The DMZ has formed a unique ecosystem through a natural ecological succession after the Armistice Agreement and has high conservation value. However, the use of facilities for the military operation and the unchecked weeding often damage the areas in the vicinities of the southern limit line's iron-railing. This study aimed to prepare basic data for the restoration of damaged barren vegetation. As a result of classifying vegetation communities based on indicator species, 10 communities were identified as follows: Duchesnea indica Community, Hosta longipes Community, Sedum kamtschaticum-Sedum sarmentosum Community, Potentilla anemonefolia Community, Potentilla fragarioides var. major Community, Prunella vulgaris var. lilacina Community, Dendranthema zawadskii var. latilobum-Carex lanceolata Community, Dendranthema zawadskii Community, Plantago asiatica-Trifolium repens Community, and Ixeris stolonifera-Kummerowia striata Community. Highly adaptable species can characterize vegetation in barren areas to environment disturbances because artificial disturbances such as soil erosion, soil compaction, topography change, and forest fires caused by military activities frequently occur in the barren areas within the southern limit line. Most of the dominant species in the communities are composed of plants that are commonly found in the roads, roadsides, bare soil, damaged areas, and grasslands throughout South Korea. Currently, the vegetation in barren areas in the vicinities of the DMZ is in the early ecological succession form that develops from bare soil to herbaceous vegetation. Since dominant species distributed in barren land can grow naturally without special maintenance and management, the data can be useful for future restoration material development or species selection.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.444-451
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• 2022

Recently, long-term cultivation is becoming more common with the increase in tomato hydroponics. In hydroponics, it is very important to supply an appropriate nutrient solution considering the nutrient and moisture requirements of crops, in terms of productivity, resource use, and environmental conservation. Since seasonal environmental changes appear severely in long-term cultivation, it is so critical to manage irrigation control considering these changes. Therefore, this study was carried out to investigate the effect of irrigation volume on growth and yield in tomato long-term cultivation using coir substrate. The irrigation volume was adjusted at 4 levels (high, medium high, medium low and low) by different irrigation frequency. Irrigation scheduling (frequency) was controlled based on solar radiation which measured by radiation sensor installed outside the greenhouse and performed whenever accumulated solar radiation energy reached set value. Set value of integrated solar radiation was changed by the growing season. The results revealed that the higher irrigation volume caused the higher drainage rate, which could prevent the EC of drainage from rising excessively. As the cultivation period elapsed, the EC of the drainage increased. And the lower irrigation volume supplied, the more the increase in EC of the drainage. Plant length was shorter in the low irrigation volume treatment compared to the other treatments. But irrigation volume did not affect the number of nodes and fruit clusters. The number of fruit settings was not significantly affected by the irrigation volume in general, but high irrigation volume significantly decreased fruit setting and yield of the 12-15th cluster developed during low temperature period. Blossom-end rot occurred early with a high incidence rate in the low irrigation volume treatment group. The highest weight fruits was obtained from the high irrigation treatment group, while the medium high treatment group had the highest total yield. As a result of the experiment, it could be confirmed the effect of irrigation amount on the nutrient and moisture stabilization in the root zone and yield, in addition to the importance of proper irrigation control when cultivating tomato plants hydroponically using coir substrate. Therefore, it is necessary to continue the research on this topic, as it is judged that the precise irrigation control algorithm based on root zone-information applied to the integrated environmental control system, will contribute to the improvement of crop productivity as well as the development of hydroponics control techniques.

• Journal of Popular Narrative
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• v.27 no.3
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• pp.13-51
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• 2021

The aim of this essay is to illustrate Sunjung Manhwa in the 1970s which has been alienated in comics studies. This essay analyses the articles and the serial comics in Schoolgirl, the magazine in the 1970s, and examines the ideal representations of the girls at that time. Sunjung Manhwa is really different between the 1960s and 1970s. It cannot be explained on this gap just by analyzing Sunjung Manhwa in book form alone. Even though the censorship on comics was the element that has hampered the development of comics as a whole, the slumps of Sunjung Manhwa in the 1970s were very excessive compared to other comics genres. This article can gain the answers to the reason of the changes of Sunjung Manhwa by studying the magazines which was the main mass media aimed at girls with Sunjung Manhwa. While the articles in magazines show the editing direction and its characteristics, they reflect the values and ideologies at that time. The same is true for the comics in the magazines. Especially, the comics in the magazines was relatively free from the censorship. This essay examined how the articles and the comics in the girls' magazine in the 1970s represented the images of girls at the time by focusing on feature articles and comics in the magazine, Schoolgirl. This article explored Um, Hee-Ja's Blue Zone and Bang, Young-Jin's Mini March among a full-length serial comics in the magazine, Schoolgirl. Both Blue Zone and Mini March reveal the images of an ideal girl that has been emphasized by the articles in Schoolgirl. Blue Zone draws the appearances of an earnest and obedient daughter, and Mini March represents the figures of a cheerful and bright girl. Through this study, it can be recognized that the magazines in the 1970s highly appraised girls who are obedient to a given society and serve to a harmonious family as ideal ones, and it might be guessed that the ideal images of girls that was characterized ceaselessly by the magazines were the standard of the censorship on comics and its creativity and had also a huge impact on the contents and the expressions of a great deal of works. The 1970s was the times when its importance has been lost in the history of the comics studies by the censorship on the comics and the monopoly of "Hapdong(합동) publisher." The limits of expression in terms of censorship were awfully distinct, so its result was few of good works in quality, and there are still many blanks in the study on 1970s' comics. This study has a meaning which fills up a blank in the comics studies.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.1
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• pp.19-29
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• 2022

The result of a questionnaire survey conducted on fishermen using coastal fish traps shows that fall accidents during trap dropping and pulling constitute the highest proportion of accidents at 42.1 %, whereas slipping accidents on the deck or stricture accidents to the body due to the trap winding device constitute 21.1 % each. In addition, 53.2 % of all surveyed subjects responded that trap pulling is the most dangerous task, followed by fish sorting 33.8 %, and trap dropping 9.1 %. As for the main items requested by fishermen for improving the trap winding device, 36.8 % indicated a method to easily lift the trap from the water to the work deck, and 31.6 % indicated a method to overcome the rope tension and prevent slip when pulling the trap to reduce the accidents. The small trap fishing vessel winding device proposed herein can increase the winding force by strengthening the rope contact area and friction coefficient via an appropriate contact angle between the driving roller of the winding device and the rope. When the contact angles between the driving roller and the rope are 1°, 5°, 9°, 14° and 19°, the rope tension showed a difference according to each contact angle. When the contact angle is 9°, the rope tension is the highest at 392.62 kgf. Based on these experimental results, a prototype winding device is manufactured, and 25 traps are installed on a rope with a total length of 100 m at 4 m intervals in the sea, and then the rope tension is measured during trap pulling. As a result, the rope tension increases rapidly at the initial stage of trap pulling and shows the highest value of 31.89 kgf, which subsequently decreases significantly. Therefore, it is appropriate to design the winding force of a small trap fishing vessel winding device based on the maximum tension value of the rope specified at the beginning of the trap pulling operation.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.1
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• pp.53-67
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• 2022

This study started from recognizing the need to study place identity from the perspective of residents experiencing the place in daily life. The subject area of the study, Shin-Cheorwon, Galmal-eup, Cheorwon-gun, Gangwon-do area, had a low population until the division of Korea in 1945. Since then, the residents have created the milieu under Shin-Cheorwon's regional historic and cultural context. Thus, the study on this area can show the formation of the interrelationship of the region and residents. The purpose of this study is to understand the meaning and identity of the everyday places of Shin-Cheorwon. Photovoice was chosen as the method for successful Participatory Research; Participant's active intervention stage, 'Documentation (4th step)', Narration (5th step), researcher's analysis stage 'Ideation (6th step)' were specifically used. As a result, the following characteristic of the places chosen by participants could be found: the meaning and relationship with the residents, similarities, and differences in people shown based on their age, length of residence, etc. Through this, participants recollected the past places, found the meaning of the place of the present, and deduced the placeness that Shin-Cheorwon should have in the future. The study identified the place identity that holds the perspective of the residents in their daily life and provides implications on the follow-up studies of place identity. In addition, it is expected that it will apply to urban planning and spatial design in further studies of how residents perceive the space formed by urban development using photovoice methodology.

• Journal of the Korean Burn Society
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• v.24 no.2
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• pp.21-29
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• 2021

Purpose: Frostbite is a hazard to people exposed to cold environments. With the progression of modern industrial development and change of leisure behavior encountering cold environments, frequent accidental exposure to frostbite injury during work and human behavior is increasing, and the predisposing factors of frostbite were greatly changed than before. The purpose of this study was to make epidemiological analysis, and to review the treatment outcomes of frostbite. Methods: From March 2010 to February 2021, this study has included 27 patients with second- to third-degree frostbite injuries in Advanced Burn Reconstruction Center, Bundang Jesaeng Hosptial. A retrospective study was made about the distribution of age, gender, predisposing factors, prevalent area, type of managements, and the length of treatment period. Results: In our institution, acute management of frostbite patients has included rewarming, anticoagulation therapy (acetylsalicylic acid), and agents to improve vascular perfusion (lipo-prostaglandin E1 [Eglandin^®]). The 25 frostbite patients with second-degree frostbite (92.6%) were successfully managed by the conservative treatment alone with a mean of 20.3 days healing time. Two patients with third-degree frostbite (7.4%) also showed good outcomes after surgical reconstruction with a mean of 59 days healing time. In our clinical experiences of third-degree frostbite, definitive surgical reconstruction should be recommended to wait for more than 4~6 weeks for identification of clear demarcation of necrotic tissue caused by frostbite. In this study, 43 frostbite injuries site in 27 frostbite patients occurred. Among them, 15 patients (55.6%) had multiple-site frostbite injury. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments (40.8%), misapplying ice pack for treatment purposes (7.4%), barefoot walking on the cold ground (3.7%), and loss of consciousness in cold grounds (3.7%). The most prevalent sites of frostbite injuries revealed as the hand (58.1%), followed by the foot (32.6%), face (7.0%), and abdomen (2.3%). And in the winter season from the November to March, the incidence rate of frostbite injuries was high at 74.1%. Conclusion: This study included 27 frostbite patients with 43 frostbite sites since last decade in a single institution at the community hospital. The frostbite patients with second-degree frostbite (92.6%) were successfully healed by the conservative treatment alone with a mean of 20.3 days healing time. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments, etc. The most prevalent site of frostbite injuries was the hand (58.1%). And the most prevalent seasonal incidence of frostbite was from November to March (74.1%).

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.128-137
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• 2002

This study was conducted to develop the heat exchanger by utilizing the heat energy of underground water(15℃), which might be used for cooling and heating system of the agricultural facilities. We developed the heat exchanger by using the parallel type plat fin tube made of Aluminum(Al 6063), which was named Aloo-Heat(No. 0247164, offered by Korean Intellectual property Office). The trial manufactures were made from Aloo-heat which was 600mm, 700mm length respectively, and It were welded to the end "U" type in order to direct flow of the underground water. The performance test was carried out under the condition of open space and room temperature with the change of flow rate of the underground water and air. The results are as follows. 1. The trial manufactures had convection heat value from 33 to 156 W/m²℃, and It was coincided with design assumption. 2. The amount of energy transfer was increased with the increment of the area of heat transfer, the air flow, the gap of temperature inlet & outlet the underground water and the air. 3. The heat value was 6,825W when the air flow was 6,000m³/h and the gap of temperature between inlet and outlet of the underground water was 6℃, and It dropped from 25.8℃ to 23.2℃(-2.6℃ difference). The convection heat value was 88.5W/m²℃. 4. The heat value was 2.625W when the air flow was 4,000m³/h and the gap of temperature between inlet and outlet the underground water was 2℃, and It dropped from 27℃ to 22.5℃(-4.5℃ difference). The convection heat value was 33.6W/m²℃. 5. Correlation values(R²) of the testing heat values of the trial manufacture type I, II, and III were 0.9141, 0.8935, and 0.9323 respectively, and correlation values(R²) of the amount of the air flow 6,000m³/h, 5,000m³/h, 4,000m³/h were 0.9513, 0.9414, and 0.9003 respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5A
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• pp.407-415
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• 2010

In Korea, more than 90% of the total number of steel bridges built for 40~70 m span length is a steel box-girder bridge type. A steel box-girder bridge is suitable for long span or curved bridges with outstanding flexural and torsional rigidity as well as good constructability and safety. However, a steel box-girder bridge is uneconomical, requiring many secondary members and workmanship such as stiffeners and ribs requiring welding attachments to flanges or webs. Therefore, in US and Japan, a plate girder bridge, which is relatively cheap and easy to construct is generally used. One type of the plate girder bridge is the two- or three-main girder plate bridge, which is a composite plate girder bridge that minimizes the number of required main girders by increasing the distance between the adjacent girders. Also, for the simplification of girder section, the stiffener which requires attachment to the web is not required. The two-main steel girder plate bridge is a representative type of plate girder bridges, which is suitable for bridges with 10 m effective width and has been developed in the early 1960s in France. To ensure greater safety of two- or three-main girder plate bridges, a larger steel section is used in the bridge domestically than in Europe or Japan. Also, the total number of two- or three-main girder plate bridge constructed in Korea is significantly less than the steel box girder bridge due to a lack of designers' familiarity with more complex design detailing of the bridge compare to that of a steel box girder bridge design. In this study, a new construction method called Turn Over method is proposed to minimize the steel section size used in a two- or three-main girder plate bridge by applying prestressing force to the member using confining concrete section's weight to reduce construction cost. Also, a full scale 20 m Turn Over girder specimen and a Turn Over girder bridge specimen were tested to evaluate constructability and structural safety of the members constructed using Turn Over process.

• The Korean Journal of Zoology
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• v.14 no.3
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• pp.139-158
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• 1971

This study was initiated to observe the growth of the lengths of the body, the antenna, the rostrum, the fore leg, the middle leg, the hind leg and the width of pronotum in the postembryonic development of Anoplocnemis dallasi. The specimens measured were fifty in the first instar larva and seventy for each instar from the second instar larva to adult stage. The authors applied the growth formula and the relative growth formula to analyse the changing pattern of the growth of each part. In this paper, having applied the formulae the y=a+bt+$ct^2$ for the absolute growth and $y=bx^{\alpha}$ for the relative growth, we obtained the following results: $\circled1$ The growth quantity: The rostrum shows the slowest, straight increase, but the other shows the curving increase. The body, the hind leg, the middle leg, the fore leg, the antenna, the width of pronotum and the rostrum are systematically slow. $\circled2$ The ratio of the growth quantity: The increase rate of the rostrum shows the straight, while the other shows the curving patterns. The largest value is the increase rate of the width of pronotum (8.816 times) and the smallest one is the rostrum (3.054 times). $\circled3$ The growth ratio for each instar: The maximal ratio of the growth quantity is in the young instar larva, but the minimal one is in an advanced instar larva. $\circled4$ The growth rate: The antenna shows a decrease pattern, while the other an increase pattern. $\circled5$ The specific growth rate: The rates of the antenna, the for leg, the rostrum, the hind leg and the middle leg show a decrease pattern. In the width of pronotum and the body, they increase in the terms of the young instar larva and they increase later. The antenna shows the most rapid decrease, and the fore leg, the rostrum, the hind and the middle leg are slow in order. $\circled6$ The "$\alpha$" of the width of pronotum shows the strongest positive allometry, but the rostrum shows the weakest negative allometry to all parts. $\circled7$ The coefficient of the relative growth of each part shows a parallel fashion in the relative growth to body length, to width of pronotum, to antenna, to rostrum, to fore leg, to middle leg and to hind leg. $\circled8$ If the coefficient of the relative growth, the growth ratio ($\alpha$) increase, the initial growth index (b) is disposed to decrease and vice versa. $\circled9$ The growth center is in the terms of the young instar larva in case of the negative allometry, but it is in the terms of an advanced instar larva in case of the positive allometry.