• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.354-357
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• 2006

Recently, remodeling of the reinforced concrete apartment became hot issue of the housing policy in Korea. In Korea, the seismic design regulation has been revised since it was established in 1988 first, in order to minimize the economic losses. It has studied that the apartments that built in 1980's and their new remodeling for seismic performance. Also lateral displacement of remodeling analysis about variation of shear-wall for apartment on the architetural remodeling. Position change by wall quantity is state that study about efficient guide line about apartment wall quantity changed at remodeling because it is factor that can influence on motion of whole building is insufficient.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.301-304
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• 2003

Nowadays, hydration heat analysis using FEM is common in thermal crack control of concrete structure. Many kinds of general FEM programs for hydration heat analysis are used in practice. But there are some problems in this using. In this study hydration heat analysis of wall according to placement length are performed. In this results we could get two conclusions. First, general structures like wall having general geometry and construction condition have similar behavior. So it is not necessary to analysis thermal crack in every case. Second, the results of 2D analysis is possible to be applied instead of those of 3D analysis because the results of 2D analysis is similar to 3D analysis in long wall having about 15~18m or over length at 3m height.

• Preventive Nutrition and Food Science
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• v.9 no.1
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• pp.92-94
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• 2004

Changes in reducing sugar and cell wall degrading enzymes during ripening of banana for 10 days were investigated. The amount of reducing sugar in bananas increased during storage at room temperature during the first 7 days, and decreased thereafter. However, starch content in banana decreased during ripening, and invertase and cell wall degrading enzymes such as cellulase, polygalacturonase and xylanase were most active after bananas were stored for 7 days at room temperature. When the bananas were stored at 4$^{\circ}C$, the magnitude of changes were much less than during room temperature storage.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.27-28
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• 2006

This study performs to investigate deformation of wall thinning pipe and to find out the position of the internal thinning defect by shearography. Shearography is one of optical methods those have applied to nondestructive testing (NDT) and the strain/stress analysis. This technique has the merit of the directly measuring the first derivative of displacement, sensitivity of which can be adjusted by the handling of optical component in interferometer. In this paper, we tested carbon steel pipe locally wall thinned and loaded internal pressure and developed the nondestructive out-of-plane deformation analysis technique fur internal thinning defect of elbow by shearography. From the results, it was confirmed that this technique is proper to the practical application on the pipe line system with internal defect.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.2 s.119
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• pp.143-148
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• 2007

This study examines the influence factor of flanking noise in the wall. Generally, there is the difference of airborne sound isolation between laboratory and field test. The purpose of this study is examing the cause of droping sound insulation performance in the field and searching the method of improving sound insulation performance. First, we measured the sound isolation in the wall at the lab. Then, we measured it in the field and compared them. At the base of these datum, we measured the flanking noise and solid transmission. For the flanking noise in the wall, we used intensive method. So, we found the influence of solid transmission.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.85-92
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• 1998

Most of tall apartment buildings constructed in our county are wall-type R/C structures composed of hear walls and slabs. It is necessary to evaluate of hysteretic properties of shear walls in wall-type R/C structures which resist lateral loads as well as axial loads. In this study, first to evaluate the wall's hysteretic behavior nonlinear analyses with IDARC 4.0 are performed for eight specimens subjected to horizontal load reversals. As a result of nonlinear analyses of specimens we can obtain three parameters which determined the hysteretic parameters such as stiffness degrading, strength deterioration and inching behavior respectively. With this three parameters, strength and deformation capacity of 5, 10, 20-story shear wall of apartment building is estimated from the results of push-over analysis.

• Earthquakes and Structures
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• v.7 no.5
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• pp.753-777
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• 2014

This study investigates the behavior of precast concrete cantilever wall systems with new vertical connections under cyclic loading. C-type steel connections for PC wall systems are proposed for the transfer of bending moments between walls in the vertical direction, whereas a shear key in the center of the wall is prepared to transfer shear forces by bearing pressure. The proposed connections are assembled easily because the directions of the slots are different at the edges of the walls. Structural performance characteristics such as the strength, ductility, and failure modes of test specimens were investigated. The longitudinal reinforcing steel bars, which are connected to the C-type connections, yielded first. Ultimate deformation was terminated owing to premature failure of the connections. The strength and deformation obtained from the cross-sectional analysis were generally similar to experimental data.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.225-232
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• 2006

Three building structures haying piloti frames in the lower two stories were selected as prototypes and were analyzed using nonlinear static analysis to investigate the seismic capacity of these buildings. The first one has a symmetrical moment resisting frame (Model 1), the second has an infilled shear wall in the central frame (Model 2), and the third has an infilled shear wall only in one of exterior frames (Model 3), The analytical results were compared with those of shaking table tests with regards to the overstrength and ductility of the irregular buildings. Infilled shear wall in Model 2 and Model 3 induced large overstrength factors, 6.8 and 6.0, respectively, which are about two times larger than that of Model 1, 3.5. The displacement ductility ratio in Model 2 was only 2.5, due to the shear failure of wall in the piloti stories, whereas those of Model 1 and Model 3 reached 3.2.

• Journal of Plant Biology
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• v.27 no.2
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• pp.43-50
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• 1984

Effects of IAA on the elongation and cell wall hlysocidase activities were investigated in excised rape (Brassica napus L. cv. Yongdang) hypocotyl segments. IAA promoted the elongation of rape hypocotyl segments. In rape hypocotyls, the first 10-mm segments from the hook exhibited maximal elongation and the capacity of elongation was gradually decreased with increasing distance of each 10-mm from the hook. A good correlation has been obtained between the magnitude of endogenous growth and the activities of $\alpha$, $\beta$-glucosidase and $\alpha$, $\beta$-galactosidase. However, exogenous application of IAA did not seem to enhance the tissue with IAA resulted in acidification of the incubation medium. From these data, we can conclude that IAA seems to enhance elongation of the tissue segments, at least in part, by releasing hydrogen ion into cell wall, some of which may participate in the cell wall extension process, but does not seem to trigger the activation of $\alpha$, $\beta$-glucosidase and $\alpha$, $\beta$-galactosidase.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.520-526
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• 2005

Automation in construction has been restricted to special classes of tasks. Curtain walls can be handled like standard construction materials; they are heavy but breakable, and are large but require precise installation. These characteristics make the installation of curtain walls ideal for robotic automation. There are two methods for developing construction robots: The first is approving the robot performance and applying it to the current construction methods. The second is admitting the limitation of the current robot technology and trying to optimize the current method of construction to apply the robot system. In this study, we derived the performance requirements of a curtain wall-installation robot. We also tested this robot at a real construction site and evaluated its performance. Finally, the results were analyzed, and we proposed additional research.