• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.47-52
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• 2000

This study was measured weight loss, total ascorbic acid, titratable acidity, and soluble solids content to investigate the effect of EPS(expanded polystyrene foam) box, LDPE film pouches and double wall corrugated fiberboard box during storage at $20^{\circ}C$. Weight loss of apple packed with corrugated paperboard box after 40 days storage was 5.7%, and those of LDPE, CE film and EPS box were 0.2-0.5%. Ascorbic acid content of apple packed with LDPE, CE, EPS was higher than that of control. Titratable acidity and total soluble solid content of control were changed 40% and 10%, and the EPS were changed 27% and 4%, respectively. Overall appearances of 'Fuji' apple packed with LDFE, CE and EPS were better than that of control.

• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.279-284
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• 2010

Four leptocephali (TL 109.8~129.7 mm) of the family Ophichthidae, collected from Sangju in the South Sea of Korea, were identified using morphological and molecular methods. Our four leptocephali were similar to Ophichthus sp. based on morphological characters: the melanophores present in series of eight gut swellings; total myomeres 144~151; body depth in total length less than 10%; eight or nine black horizontal bands present from anus to caudal fin base. On the other hand, our four leptocephali were identified to Pisodonophis sp. based on 826 base pairs of 12S rRNA gene nucleotide sequences. Our results showed that morphology-based identification did not agree with molecular identification, indicating difficulty in differentiating morphologically between Ophichthus and Pisodonophis leptocephali. We, herein, firstly describe morphological characteristics of Pisodonophis sp. leptocephali from Korea.

• Korean Journal of Ichthyology
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• v.23 no.3
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• pp.217-224
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• 2011

The seven leptocephali (14.6~68.0 mm in total length) of the family Ophichthidae, from the East Sea of Korea, were identified using 12S rRNA 861-bp sequences and their morphological development were described. Our seven leptocephali were identified to Echelus uropterus based on genetic distance (d=0.000) being well consistent with that of adult E. uropterus. Our seven leptocephali of E. uropterus are characterized by morphological combinations: caudal fin present; the melanophores present in series of nine gut swellings; total myomeres 154~158; body depth in total length less than 10%; eight black horizontal bands present from anus to caudal fin base. Our morphological and molecular results suggest that E. uropterus may be an intermediate group between subfamily Ophichthinae and Myrophinae.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.757-766
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• 2015

This study was considered chances of additional income, if farmers raised silkworms in unused mulberry leaves, after harvesting mulberry, investigated yields of mulberry leaves in vinyl-house and optimal amount in raised silkworms, First, the results was investigated productions of mulberry leaves in the mulberry tree-shape of vinyl-house, T-shape harvested 7.07 kg, Y-shape was 6.55 kg, in comparison with convention of it was harvested 4.75 kg mulberry leaves/1 mulberry tree, was harvested 49%, 38% more each. Also, yields of mulberry leaves was used 302 kg when was raised 1box of silkworms in the mulberry tree-shape of vinyl-house. In other hand, yields of raising silkworms was analysed in the mulberry tree-shapes of vinyl-house, mulberry leaves of $1,000m^2$ vinyl-house mulberry tree was raised average of 3.74 boxs silkworms, in the concrete conventional-shape was 3.24 boxs, T-shape did 4.17 boxs and Y-shape was 3.83 boxs, Consequently, if the farmers of $1,000m^2$ vinyl-house mulberry tree raised silkworms with unused mulberry leaves, could get 1~1.2 million won additionally.

• Journal of Korean Society of Steel Construction
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• v.19 no.1
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• pp.117-127
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• 2007

In this study, we evaluate the strength of steel box beam-to-column connections subjected to axial loads in steel frame piers. The T-connection strength was reduced due to the column axial force in the two-story pier structure. To examine this phenomenon, non-linear FEM analysis was carried out and the analytical procedure was verified by comparing it with experimental results. To clarify the effect of the axial force and major design parameters in connection with strength, influence of panel zone width-thickness ratio, sectional area, and axial force was investigated using FEM analysis. Also, the theoretical strength equations were suggested by stress distribution of panel zone. The strength of the T-connection was compared with one of the one-story pier structure connections. As a result, the strength evaluation equations are proposed in consideration of the panel zone width-thickness ratio and sectional area ratio for the T-connections.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.2
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• pp.88-97
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• 2011

For Korean design provisions are not equipped for skewed steel box girder bridges, when American provisions are adopted, load distribution factors different from real behavior are determinated. Furthermore the possibility of over or under estimated bridge design involves. The aim of this study is to provide more rational load distribution factor formulas based on real behavior for shear at obtuse corner of skewed steel box girder bridges. In order to accomplish the aim finite element analysis for a variety of skewed steel box girder bridge structural models is carried out, and each parameters degree of influence on wheel load distribution factors of skewed steel box girder bridges are analyzed. Then multiple regression analysis is fulfilled in order to propose formulas for determinating shear force load distribution factor of skewed steel box girder bridges.

• Journal of Conservation Science
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• v.33 no.1
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• pp.17-24
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• 2017

Studies were conducted on manufacturing techniques by applying microscopy and conservation treatments on the annals of Joseon dynasty storage box at the National Museum of Korea. The results revealed that lime tree wood(Tilla spp.) was used to make the annals of Joseon dynasty storage box. Lacquering techniques were used to coat the box with a layer of lacquer and bone ash and then cover it with traditional Korean paper. After being covered with traditional Korean paper, more layers were applied in the following sequence: mud ashes, black lacquer, pure lacquer, and black lacquer. Before conservation treatments, some components and lacquer layers were missing in addition wood joint were loose. Therefore, conservation and restoration should be conducted based on the identified wood and by observing the shape of the remaining components.

• Journal of Navigation and Port Research
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• v.27 no.2
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• pp.199-207
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• 2003

In the combat environments at the sea, the naval ships should have enough structural integrity to perform the task under the enemy's attack and possible damages. Although the naval ships can be damaged from the enemy's attack, those damages should be minimized and the naval ships must maintain their combat capabilities continuously after recoveries from the damages. Therefore, it is ve교 important for modem naval ships, especially combat naval ships, to ensure the survivability. This paper reviewed the developing procedure for the technique of the naval ships structures and described method, especially box girder system considering survivability. The efficiency of box girder is examined by numerical simulation, and it is found that the establishment of box girder is a good design method to improve the survivability.

• Korean Journal of Agricultural Science
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• v.23 no.2
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• pp.227-232
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• 1996

It is a tedious job to handle seedling trays in a green house with human hands because of their fluctuation when they are moving. A robotic gripper for handling a seedling tray has been developed., which has two fingers consisting of the vertical and horizontal bars. The maximum deflections at the center of the seedling trays were measured with various lengths of the horizontal bars. The length of 250 mm was revealed to be optimal one, resulting less than 15 mm deflection with a $540{\times}270mm$ seedling tray, which was acceptable for a practical use. For this study a LM system was adopted to move the fingers. To validate this system the robotic gripper was installed on a Cartesian robotic manipulator and their performance was tested several times with great success. The robotic manipulator used in this study was a general one, so a special one for this robotic gripper needs to be developed in future.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.179-185
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• 1999

The study which was conducted to determine the effects of the polyethylene film on the culture of Pleurotus ostreatus is summarized in the following: 1) The fresh weight of Pleurotus ostreatus cultured by the box culture method mulching with black polyethylene film was 2,237g/box and, 2,028g/box by white polyethylene film mulching, and 1,695g/box at the conventional culture which was by 24.2% and 16.4% higher than that of the conventional culture.2) The fresh weight of P. ostreatus cultured by the shelf culture method mulching with the black polyethylene film was 17.4kg/m$^2$ at the white polyethylene film culture, 14.6kg/m$^2$ at the conventional culture which was by 16.2%, 7.5% higher than that of the conventional culture. 3) The best shape appearance in terms of the diameter in P. ostreatus was 5~30mm and the intervals were 10cm respectively. 4) The black polyethylene film mulching in P. ostreatus observed in good protection against Pseudomonas spp., Trichoderma, or mushroom flies. 5) The black polyethylene film mulching method for the culture of P. ostreatus was much better than that of the shelf-culture, box-culture or the sack culture in terms of total yield and quality. 6) The length of harvesting implement of P. ostreatus was suitable for 45~120cm in order to use on the harvest of the mulching.