• Journal of Korean Association for Spatial Structures
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• 제2권3호
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• pp.81-92
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• 2002

The objective of this paper is to help to make decision of the appropriate structural types in long span structured building due to range of span. For the intention, based on 7 forces of structural element, it is analized the relationships among 6 configurations of structural element(d/1), 25 structural types, 4 materials, and span-length known with 186 sample from 1850 to 1996. 1) bending forces: $club(1/100{\sim}1/10),\;plate(1/100{\sim}1/10),\;rahmen(steel,\;10{\sim}24m)\;simple\;beam(PC,\;10{\sim}35m)$ 2) shearing forces: $shell(1/100{\sim}1/1000)\;hyperbolic\;paraboloids(RC,25{\sim}97m)$ 3) shearing+bending forces: plate, folded $plate(RC21{\sim}59m)$ 4) compression axial forces: club, $arch(RC,\;32{\sim}65m)$ 5) compression+tension forces: shell, braced dome $shell(RC,\;40{\sim}201m),\;vault\;shell(RC,\;16{\sim}103m)$ 6) compression+tension axial forces: $rod(1/1000{\sim}1/100)$, cable(below 1/1000)+rod, coble+rod+membrane(below 1/1000), planar $truss(steel,\;31{\sim}134m),\;arch\;truss(31{\sim}135m),\;horizontal\;spaceframe(29{\sim}10\;8m),\;portal\;frame(39{\sim}55m),\;domical\;space\;truss(44{\sim}222m),\;framed\;\;membrane(45{\sim}110m),\;hybrid\;\;membrane\;(42{\sim}256m)$ 7) tension forces: cable, membrane, $suspension(60{\sim}150m),\;cable\;\;beam(40{\sim}130m),\;tensile\;membrane(42{\sim}136m),\;cable\;-slayed(25{\sim}90m),\;suspension\;membrane(24{\sim}97m),\;single\;layer\;pneumatic\;structure(45{\sim}231m),\;double\;layer\;pneumatic\;structures(30{\sim}44m)$

• Journal of Biosystems Engineering
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• 제29권1호
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• pp.29-36
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• 2004

The geometric characteristics of the Altari radish were measured for the purpose of mechanization of the kimchi processing. In this study, geometric characteristics such as the sectional area and volume of the radishes(pyeong-gang and sa-chul) were calculated using the image processing method, and physical properties such as the compressive strength, the cutting force of the radish and the torsional moment of the radish leaf-stems were measured by using a universal testing machine. In case of the radish(pyeong-gang), the weight was ranged 215.0∼465.0 g, the length of the radishes(body) was 86.3∼129.2 mm, the diameters were 43.3∼58.1 mm, and the length of the leaves was 261.3-368.2 mm. And the vertical compressive strengths were ranged 83.8∼171.7 N/$\textrm{cm}^2$, the horizontal compressive strengths were 113.0∼176.3 N/$\textrm{cm}^2$, the shearing forces were 86.0∼114.6 N, and the surface hardness was ranged 51.1∼52.1 N/$\textrm{cm}^2$. In case of the radish(sa-chul), the weight was ranged 203.5∼412.2 g, the length of the bodies was 67.5∼127.0 mm, the diameters were 22.3∼59.8 mm and the length of the leaves was 245.6∼312.6 mm respectively. And the vertical compressive strengths were ranged 91.3∼168.3 N/mm, the horizontal compressive strengths were 132.6∼186.9 N/$\textrm{cm}^2$, the shearing forces were 89.4∼116.5 N, and the surface hardness was ranged 52.4∼67.8 N/$\textrm{cm}^2$, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.418-423
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• 1998

This paper is intended to investigate the behavior of flexural-shear cracking in reinforced concrete beams without web reinforcement with FEM incorporated into a linear elastic fracture mechanics approach(LEFM). Each crack was propagated progressively by a finite length, then the quantitative reponses were examined. The results show that the horizontal crack was initiated by the bond-jnduced shear stress due to horizontal shearing action of the T-C force couple after the formation of the critical flexural crack. Also, the horizontal crack is considered to be a major factor of shear failure in slender reinforced concrete beams without web reinforcement.

• Proceedings of the Korean Geotechical Society Conference
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.131-136
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• 1999

In this study, novel activated silicate grout solution for injection grouting was prepared by the reaction of ordinary waterglass with alkaline earth metal salts mixture by means of the high-speed stirring method with strong shearing force, and its chemical and physical properties were investigated. The variation of its gelation time plotted with the amount of dilution water showed that this novel silicate had better gelation characteristics in comparison with ordinary waterglass. And some other engineering characteristics of this grout such as durability and mechanical properties were investigated experimentally. The whole experimental results established that this novel silicate grout was a good alternative with an existing ordinary waterglass grouting method.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제50권3호
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• pp.250-256
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• 2017

This study investigated the removal efficiency of organic matter and nitrogen from fish farm effluent by hydraulic retention time (HRT) using an upflow biological filter (ANR system) reactor. The recycling time and influent flow in the reactor were controlled to 14.8, 7.4, 5.5 and 3.2 h to evaluate HRT. In addition, each reactor was coupled to a fixed bed upflow filter charged with media. The results showed that removal efficiency was ${\geq}95%%$ with an HRT of 5.5 h, and nitrification efficiency was reduced to 81% with an HRT of 3.2 h, although nitrification efficiency temporarily decreased due to the shock load as HRT decreased. Total nitrogen removal rate was also reduced to about 65% with an HRT of 3.2 h, which was considered a washout effect of nitrifying and denitrifying microorganisms by increasing the shearing force to the filter media, which decreased organic matter and nitrogen removal efficiency.

• Journal of Korean Society of Steel Construction
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• 제13권2호
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• pp.163-176
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• 2001

In this paper, the stress resultants and displacements of simply supported curved girder based on the flexural torsional theory considering torsional warping effects are analyzed. And elastic equations of continuous curved girder are obtained by using energy method. Also, bending moment warping torsional moment diagram, pure torsional moment diagram, shearing force diagram, and deflection diagram of continuos curved girder bridge subjecting to vertical loads and uniform loads are presented.

• Journal of the Korean Ceramic Society
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• 제31권2호
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• pp.161-170
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• 1994

For the preparation of short ceramic fibers of which average length might be in accordance with the opening size of sieve, e.g., 150${\mu}{\textrm}{m}$ or 300${\mu}{\textrm}{m}$, bulk fibers were grounded on sieve screen by applying both compressing and shearing force, and passed through the sieve screen. The grounded fibers were subjected to gravitational settling processes. The classified fibers were observed by scanning electron microscopy and the length of each fiber was measured to correlate the average length with the opening size of the sieve used for grinding bulk fibers. Theoretical analysis show that a free settling technique is ineffective for the classification of fibers by length compared with that of particles. The average lengths of classified fibers estimated by scanning electron microscopy were in good agreement with those obtained by relative packing volume of the fibers. Accordingly, it is confirmed that average fiber lengths can be determined from bulk volume data without photographing, counting and averaging results for hundreds of fibers.

• Journal of the Korean Society of Food Culture
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• 제30권3호
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• pp.313-323
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• 2015

One of the main processes of tenderizing beef in Joseon Dynasty was chemical methods involving Apricot seeds, manchu cherry twig and leaves, bamboo skins, mulberry tree bark, mangsa (硭砂), salmiacum (磠砂), alcohol, fermented malt, and original honey. This study analyzed and compared the effect of broussonetia papyrifera, fermented malt, cherry trees, and mulberry tree bark from old cookbooks. Tenderizing beef with cherry trees was most effective in the experiment on shearing force, TPA, and electrophoresis of beef. According to sensory evaluation and electrophoresis test results, tenderized beef with mulberry tree bark was slightly more preferred over the method using cherry trees. However, in accordance with the above mentioned experiment, quantitative descriptive analysis showed that the most common tenderizing material was derived from morus alba powder.

• Journal of The Korean Astronomical Society
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• 제37권4호
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• pp.243-248
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• 2004

Disk galaxies abound with intermediate-scale structures such as OB star complexes, giant clouds, and dust spurs in a close geometrical association with spiral arms. Various mechanisms have been proposed as candidates for their origin, but a comprehensive theory should encompass fundamental physical agents such as self-gravity, magnetic fields, galactic differential rotation, and spiral arms, all of which are known to exist in disk galaxies. Recent numerical simulations incorporating all these physical processes show that magneto-Jeans instability (MJI), in which magnetic tension resists the stabilizing Coriolis force of galaxy rotation, is much more powerful than swing-amplification or the Parker instability in forming self-gravitating intermediate-scale structures. The MJI occurring in shearing and expanding flows off spiral arms rapidly forms structures elongated along the direction perpendicular to the arms, remarkably similar to dust spurs seen in HST images of spiral galaxies. In highly nonlinear stages, these spurs fragment to form bound clumps, possibly evolving into bright arm and interarm H II regions, suggesting that all these intermediate-scale structures in spiral galaxies probably share a common dynamical origin.

• Journal of Korean Physical Therapy Science
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• 제3권1호
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• pp.895-905
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• 1996

A whiplash injury of cervical spine is typically caused by a special kind of accident. It usually involves a driver of an automobile who experiences a direct impact from behind. There are no external signs of the injury, but shearing forces from the rapid flexion and extension momement result in segmental lesions. The extent of injury to the tissue depends upon the force of impact, the exact position of head at the moment of impact, the awareness of impending injury in order to "prepare" the musculature, and the normalcy of all the tissues of the neck. Diagnosis demend a carefully detailed history and a through musculo-skeletal--neurological examination. Whenever possible, the symptoms claimed must be verified by a carefule neurological examination.