• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.103-110
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• 1994

Since the supply of the Southeast Asian tropical timber decreases and its price steeply increases in the international lumber market, door and window frame manufacturers in this country are eagerly searching for their substitutes. This is the first step to replace Southeast Asian tropical timber by low grade North American softwoods, whose reliable and steady supply is expected, but their appearances are not as good as the tropical timber. In this study, knot distribution on the softwood boards and their warp were examined The yield and production cost were also calculated. The average numbers of knots on a door frame were 7.2 for Douglas-fir and 3.4 for Western hemlock. Only 11% of the knots of Douglas-fir door frames are larger than 5cm in diameter, while are 35% of the knots of Western hemlock. The deformations of door frames, after 2 months air-drying, were measured with a warp table. The deformations of Western hemlock door frames were mostly less than 6mm, while those of Douglas-fir distributed in the range of 0.5 and 9.5mm. The yield of Western hemlock is higher than that of Douglas-fir. It can be concluded that the door frames made of the softwoods are compatible with those made of the tropical timber in most aspects except appearance.

• Conservation Science in Museum
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• v.15
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• pp.96-121
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• 2014

Portrait of Sim Huisu is a seventeenth-century Joseon portrait of a meritorious vassal. The National Museum of Korea currently owns two portraits of Sim Huisu, which are the eldest son's family and by the eldest grandson of the family's second eldest son. Both were donated in 1980. Portraits were still in its original mounting, but the supporting silk had been damaged and stained in a flood. Conservation treatment was undertaken to restore the original style, and scientific analysis, such as, X-ray, XRD, XRF and Graff "C" stain, was conducted to study the materials and painting techniques. The support silk was found to be refined fibroin and a plain weave consisting of two weft threads and one warp thread. The lining papers were found to be bamboo fiber paper of first layer in China and Korean traditional mulberry paper in second. Various pigments were identified in the painting, including white lead, cinnabar, atacamite, ink stick, azurite, silver, and gold. The study also confirmed the use of the back painting, with colors such as white ^{White Lead}, green ^Atacamite, orange ^Minium, black ^{Ink Stick}, and yellow ^Dye. Also, it was found that stick ink or dye was used with white lead.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.3
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• pp.133-138
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• 2006

This experiment was conducted to determine the effect of wrap color on the quality of round baled grass silage at experimental field of Grassland and Forages Division, National Livestock Research Institute, RDA, Suwon from 1997 to 1998. The experiment was consist of randomized block design with three replications. The treatments were three wrap color(white, black and light green). Wrap color did not affect chemical composition. Fiber components(ADF and NDF) of all silages after 2 months were higher than those of forages at ensiling. Among tested wrap colors, white color wrap resulted in lower pH than others (p<0.05) but, there was no significant difference between black and light green color. Dry matter content of light green color was the highest among warp colors, but there was no signifiant difference (p<0.05). Acetic and butyric acid contents of all plots. were not found significant difference among wrap color and wrap color did not influence lactic acid and organic acid concentration. The effect of wrap color on the quality grade and DM loss also were not found significant difference. Results of this study indicate that wrap color does not influence the quality of silage.

• Composites Research
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• v.18 no.6
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• pp.9-18
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• 2005

With the wide applications of fiber-reinforced composite material in aero-structures and mechanical parts, the design of composite joints have become a very important research area because the joints are often the weakest areas in composite structures. This paper presents an analytical study of the stress distributions in mechanically single-fastened and multi-fastened composite laminates. The finite element models which treat the pin and hole contact problem using a contact stress analysis are described. A dimensionless stress concentration factor is used to compare the stress distributions in composite laminates quantitatively In the case of single-pin loaded composite laminate, the effects of stacking sequence, the ratio of a hole diameter and the width of a laminate (W/D ratio), the ratio of hole diameter and distance from edge to hole (E/D ratio), friction coefficient and clamping force are considered. In the case of multi-pin loaded composite laminate, the influence of the number of pins, pitch distance, number of rows, row spacing and hole pattern are considered. The results show that P/D ratio and E/D ratio affect more on stress distributions near the hole boundary than the other factors. In the case of multi-pin loaded composite laminate, the stress concentration in the double column case is better than the other cases of multi-pin loaded composite laminate.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.1
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• pp.84-97
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• 2017

Water vapor and thermal transmission properties of high emotional garments are important to evaluate wear comfort; in addition, the measuring methods of these properties are also critical for breathable and warm suit fabrics. In this study, the water vapor and thermal properties of composite yarn fabrics made of CoolMax, Tencel, and Bamboo fibers with filaments were measured and compared according to the measuring method. Water Vapor Transmittance (WVT) of the fabric woven by the sheath/core composite yarn in the warp direction was the highest due to the small staple fiber volume in the sheath/core yarn structure and high air voids in the sheath/core yarn fabrics. This property was also the highest in fabrics woven by bamboo staple yarns in the weft direction, and was the lowest on hi-multi filament fabrics. However, water vapor resistance ($R_{ef}$) of these fabrics by KSK ISO 11092 showed the opposite results to the water vapor transmittance method ($CaCl_2$ method); in addition, its correlation coefficient was low. The correlation coefficient between $R_{ef}$ and the drying rate was 0.719; therefore, the measurement mechanism of $R_{ef}$ is analogous to the drying property measurement. The thermal conductivity of the fabrics woven with compact staple yarn showed a high value; however, the hi-multi filament fabric showed low thermal conductivity. Therefore, fiber characteristics affect thermal properties more than yarn structure. The correlation between thermal property and moisture transport was also low. This study showed that: water vapor transmittance was active at the loose yarn structure, dry heat transport was vigorous at the compact yarn structure, and heat transport was affected more by fiber characteristics than yarn structure. In conclusion, sheath/core composite yarns were relevant to the high absorptive cool suit along with siro-fil and CoolMax/Bamboo staple yarns that were relevant to the heat diffusive cool suit.

• The Journal of the Korea Contents Association
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• v.17 no.3
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• pp.42-52
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• 2017

Panorama image is a single image obtained by combining images taken at several viewpoints through matching of corresponding points. Existing panoramic image generation methods that find the corresponding points are extracting local invariant feature points in each image to create descriptors and using descriptor matching algorithm. In the case of video sequence, frames may be a lot, so therefore it may costs significant amount of time to generate a panoramic image by the existing method and it may has done unnecessary calculations. In this paper, we propose a method to quickly create a single panoramic image from a video sequence. By assuming that there is no significant changes between frames of the video such as in locally, we use the FAST algorithm that has good repeatability and high-speed calculation to extract feature points and the Lucas-Kanade algorithm as each feature point to track for find the corresponding points in surrounding neighborhood instead of existing descriptor matching algorithms. When homographies are calculated for all images, homography is changed around the center image of video sequence to warp images and obtain a planar panoramic image. Finally, the spherical panoramic image is obtained by performing inverse transformation of the spherical coordinate system. The proposed method was confirmed through the experiments generating panorama image efficiently and more faster than the existing methods.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.522-537
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• 2020

The Joseon dynasty had close communication with the Ming and Qing dynasties on multiple levels. In the development process of furniture modeling design, the same cultural source and mutual communication, and the same factor was reflected in each other's furniture modeling. In this paper, "Furniture in the later Joseon Period" and "Ming style furniture" are taken as the research noumenon, table furniture as the specific research object, and from the perspective of "similarity" in the history of exchanges between the two countries, the overall modeling design and the local modeling design are selected to discuss the modeling design of traditional furniture in the two countries. In the analysis of specific research cases, there are similar genes in the overall modeling design of table furniture such as soban, warp bed and inkstone bed in the later Joseon Dynasty and table furniture such as kang, square table, wine table and incense table in the Ming and qing dynasties. In terms of local modeling, the appearance of similar desktop, cloud horn, leg, foot and other modeling designs better confirms the similarity in modeling design between the two countries. In this paper for "type of air hole" formative source speculated that traditional furniture is for Korean peninsula a tentative study of cultural studies. Considering the fact that the exchanges between Korea and China are expanding in many aspects, exploring the similarities in the traditional furniture will help to analyze the cultural exchanges between the two countries and promote the exchanges.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.2
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• pp.164-171
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• 2002

In this study, a mass-spring model is used to dynamically describe and calculate the shape and movement of a mid-water trawl system. This mathematical model theorizes that the factors constituting the system are the material points and the external forces such as hydrodynamic load, gravity, and buoyancy act on these material points. In addition, it surmises that these material points are connected to each other by springs, the springs do not have any mass, and the internal force acts on these springs. The non-linear differential equations are implicitly integrated with time for guaranteeing a stable solution. The dynamic simulation by the mass-spring model shows the status of the gear such as fishing gear depth, distance between doors, shape of the gear, and tension of each line. It depends on the parameters such as towing force, warp length, force of a sinker, buoyancy of a float, type of door and netting materials. The validity of the model is verified by comparing simulation motions of a trawl system obtained from computed values to those from an actual experiment.