• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.425-426
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.589-590
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.805-806
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• 2013

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.4
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• pp.97-105
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• 2004

As modern society has been progressed, the demolition method of concrete structure that satisfy the condition of safety, economic efficiency, and environment-friendliness is required. This study investigated problems of existing demolition methods and developed modified method minimizing cooling water and sludge for demolition job. It was also verified the validity of this method based on the finite element methods. A analysis parameters as a number, depth and size of boring, and self weight were introduced for this study, and gave optimal condition for the demolition job and analysis.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.577-580
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• 2003

Problem of repairing by boring is that it deteriorates stabelety and durability of structure by permeation of seawater from underneath after damage and repair of reinforcing rod regarding of spot. The purpose of this study is to improve the porblem by using the repair method of general boring to mend the of large mat basis. Direction of thes experiment is to apply the new repair material and the method to control the blazing fire factor caused by the crack from the foundation of large mat and also to estimate it's integrity. New method of construction is method of contruction that do speace scurity in vertical drilling and bottom useing water jet. New material used bantonite and rubberized asphalt. Test result existent repair method of construction large size mat basis perforation is difficult and reinforcing rod can be damaged coule there were a lot of problems with re-water leakage of crack repair region, but overcomes existent short coming by method that apply in this study.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.807-808
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• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.811-812
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• 2013

• The Korean Journal of Zoology
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• v.5 no.2
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• pp.9-12
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• 1962

The present observations on the perforation bored into young bivalve Tapes philippinarum (less than 2 mm in shell length) by boring snails were conducted at Sunjae Island in 1960 and Inchon Harbor inn 1962. 1. Young bivalves of the species which were left with bored in them were found both in Inchon Harbor and Sunjae Island. 2. The location of the holes in the valves of the young bivalve varied widely, while the holes of the adult bivalve were located at relatively definite position in the valves. 3. The author realized that the holes are bored by a species of snails that have radulas, for the inner diameters of the holes were much smaller than the router diameters. 4. The size of the holes in the valves of young bivalve was much smaller than those holes bored in adult valves. The minimum size of the holes was only 7.5microns in diameter. 5. The author considered that the boring snail is Natica severa that is found abundantly in Inchon Harbor and Sunjae Island and that this snail is the only species found in the particular areas and performs the above mentioned behavior. However, the author could not confirm experimentally the snail drilling young bivalve of Tapes philippinarum .

• Journal of the Korean Geotechnical Society
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• v.33 no.1
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• pp.5-15
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• 2017

Skin friction may be one of the most critical factors in designing the prebored and precast pile. Special attention was given to the interface behavior of cement milk-surrounding soil during the installation of prebored and precast pile. Small-scale field model pile test was conducted for the case of single pile. The size and geometry of the small-scale field model piles were designed with pile length 1.3m, boring diameter 0.067 m. Quick maintain-load test was conducted for the cases of boring diameter 150, 125, 90, 86, 74 mm and water-cement ratio 90, 70, 60%. It was shown that the bearing capacity of the pile increased as the cement-water ratio and cement milk thickness increased. Considering the scale effect between the small-scale model test and the actual construction site, it was found that cement milk thickness of 0.1~0.4D (50~200 mm) was reasonable for the stability of the structure. Also, the proper cement paste water / cement ratio was about 70% when considering the results of this study and quality control.

• Korean journal of applied entomology
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• v.5_6
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• pp.59-63
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• 1968

This Paper deals With the biology and the life Cycle of Eriophyes kuko KISHIDA. 1. The host of Eriophyes kuko KISHIDA is Lycium chinense MILL (Boxthorn), Solanum nigrum LINNE(Morel) and Capacium annum LINNE(Red pepper) etc. 2. Eriophyes kuko KISHIDA is migrated and propagated by physical carriers. The direction of the wind has a great influence upon migration and dispersal. 3. The number of e99s deposited by a adult female is $28.5\pm0.449$ egg period is $7.0\pm0.447$ and larval period is $4.33\pm0.667$ days respectively. 4. The size of gall diameter on the leaf of Lycium Chinense MILL after boring in each date by Eriophyes kuke KISHIDA is as follows, 1st day after boring is $290.5\pm0.3415\mu$ End 25st day after boring is $3260.5\pm0.5157\mu$ in average. 5. Adult periods are from 25 to 30 days and the egg laying period is 6 days. 6. Eriophyes kuko KISHIDA has 6 to 7 generations in a year, and hibernate they over winter in the gall as an adult. The first adult appears in late May.