• Journal of Urban Science
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• v.7 no.2
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• pp.21-27
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• 2018

With the increase of the skyscraper center, the development of large-diameter and high-strength reinforcing bars is being carried out to solve the dense reinforcement. In case of the steel reinforced concrete with a small cross section such as beam-column joints, the development length becomes short when straight bars are used. Therefore, it is possible to solve the problem that the development length becomes short by using the bearing strength of the hooked bar and headed bar. In this study, the exterior beam-column joint test of SD700 hooked bar and headed bar with anchorage length of 20db was conducted to extend the development length limitation of hooked bar and headed bar. As a result of the evaluation of the anchorage strength using the design equation by KCI, the average of the [measured value]/[predicted value] ratio was 1.31 for the hooked reinforcing bars. In the case of headed bars, the average of the [measured value]/[predicted value] ratio was 1.12. In addition, in order to compare the anchorage performance of the hooked bar and the headed bar, the measured values were divided by the square root of the compressive strength of the concrete to compare the anchorage strength. Under the same conditions, the anchorage strength of headed bars was 8.5% higher than the hooked bars.

• Korean Institute of Interior Design Journal
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• v.16 no.5
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• pp.47-54
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• 2007

The change of modern society arouse the issue of the family structure and the demand of upbringing. According to the issue, the need of the upbringing is the big interest in society. This study is on the demand of the parents of students in eco-environmental space in child care center. The purpose of the study makes the suggestion the need of the eco-environmental space in child care center. The study progressed with looking up and giving questionaires in six child care centers which have eco-environmental space in Seoul. 210 questionaires were given out to parents and taken away 180 questionaires. The result of the study, parents required strongly to have the eco-environmental space in child care center. The natural interior materials, nature experimental outdoor ground and exterior garden were preferred overriding. The use of the woods and stones and eco-environmental adhesives are required as the natural Interior materials. And the natural light source can be imported in sky light, side window and atrium. Upcoming study would be directed in child care center without eco-environmental spaces. The next suggestion would be made in the needs of the eco-environmental space in child care center.

• Korean Institute of Interior Design Journal
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• v.20 no.2
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• pp.47-54
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• 2011

In Alvar Aalto's designs, important factors of complex building designs including Wolfsburg cultural center are that they insinuate how to develop each architectural type and how to combine them in a building. The humane and physical background studies, and wholistic and systematic approaches are adopted to fulfill research purposes. Comparison with other buildings are necessary to reveal true meaning of this building. The result of analysis show characteristics of Wolfsburg cultural center as follows; hybrid composition of mass and elevation, spatial effect using level difference and light, massing variation of roof, and creating space for various activities. Wolfsburg cultural center designed in late 1950s has greatly affected Aalto's later works through various architectural experiments because it is the first cultural complex project that combined various architectural types. Especially library in the cultural center has shown transitional characteristics to famous fan-type libraries of 1960s while maintained features about Viipuri library. Wolfsburg cultural center act as an another type which present new principles of clustering, massing and exterior design. Its true meaning lies in forming a humanizing place beyond spatial configuration.

• Earthquakes and Structures
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• v.26 no.2
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• pp.131-147
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• 2024

Damage caused by an earthquake depends on not just the intensity of an earthquake but also the region-specific construction practices. Past earthquakes in Asian countries have highlighted inadequate construction practices, which caused huge life and property losses, indicating the severe need to strengthen existing structures. Strengthening activities shall be proposed as per the proposed weighting factors, first at the higher weighted members to increase the capacity of the building immediately and thereafter, the other members. Through this study on gravity load-designed (GLD) buildings, relative weights are assigned to each storey and exterior and interior columns within a storey based on their contribution to the energy dissipation capacity of the building. The numerical study is conducted on mid-rise archetype GLD buildings, i.e., 4, 6, 8, and 10 stories with variable storey heights, in the high seismic zones. Non-linear static analysis is performed to compute weights based on energy dissipation capacities. The results obtained are verified with the non-linear time history analysis of 4 GLD buildings. It was observed that exterior columns have higher weightage in the energy dissipation capacity of the building than interior columns up to a certain building height. The damage in stories is distributed in a convex to concave parabolic shape from bottom to top as building height increases, and the maxima location of the parabola shifts from bottom to middle stories. Relative weighting factors are assigned as per the damage contribution. And the sequence for strengthening activities is proposed as per the computed weighting factors in descending order for regular RCC buildings. Therefore, proposals made in the study would increase the efficacy of strengthening activities.

• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.411-420
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• 2007

The applicability of headed bars in exterior beam-column joints under reversed cyclic loading was investigated. A total of ten pullout tests were first performed to examine pullout behavior of headed bars subjected to monotonic and cyclic loading with test variables such as connection type between head and bar stem (weld or no weld), loading methods (monotonic or cyclic loading), and head shape (small or large circular head and square head). Two full-scale beam-column joint tests were then performed to compare the structural behavior of exterior beam-column joints constructed using two different reinforcement details: i.e. $90^{\circ}$ standard hooks and headed bars. Both joints were designed following the recommendations of ACI-ASCE Committee 352 for Type 2 performance: i.e. the connection is required to dissipate energy through reversals of deformation into inelastic range. The pullout test results revealed that welded head to the stem did not necessarily result in increased pullout strength when compared to non-welded head. Relatively large circular head resulted in higher peak load than smaller circular and square head. Both beam-column joints with conventional $90^{\circ}$ hooks and headed bars behaved similarly in terms of crack development, hysteresis curves, and peak strengths. The joint using the headed bars showed better overall structural performance in terms of ductility, deformation capacity, and energy dissipation. These experimental results demonstrate that the headed bars using relatively small head can be properly designed far use in external beam-column joint.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.260-266
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• 2006

The construction of settlement house in a permanent rental housing development area started between 1989 and 1992, planning of supplying two hundred fifty thousand residences, settlement house became compulsory as a welfare facilities. As a part of Welfare program for low income families, number of settlement housing increased dramatically, also domiciliary welfare center was beginning to set up as a branch of settlement housing to strengthen its service towards families and local communities, thus numerous social welfare organizations play a crucial part in resolving a welfare problem for low income families while satisfying local community's needs. However, despite of these efforts, the number if institutions cannot handle demand of local community's needs and number of welfare institution programs. as a solution, the alternation of space is being used, however, it did not solve basic problem, even worsen in terms of space efficiency.

• Journal of TMJ Balancing Medicine
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• v.2 no.1
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• pp.1-7
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• 2012

Objectives: The purpose of this review is to investigate the relationship between the extra meridians and the temporomandibular joint. Methods: Literature review on the eight extra meridians and theoretical considerations were performed with a focus on the relationship with the temporomandibular joint. Results: Extra meridians are crucial in the maintenance of the balance of the whole body, especially the structural balance of the anterior-posterior, left-right, superior-inferior, and interior-exterior regions. The foundation of extra meridians occurs in the lower abdominal area and the innate qi. Conclusions: Extra meridians are important players in the maintenance of the balance and harmony within the body, and may function cooperatively with the temporomandibula joint in its role to maintain the yinyang balance within the body.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.1
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• pp.84-89
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• 2013

Titanium used in industry has been widely applied for aerospace engine, structures and spacecraft exterior, etc. because the titanium is higher in strength compared to the steel and light in weight compared to the steel. This study is to investigate the effect of cutting depth and cutting time on the spindle speed and feed rate of vertical machining center as a parameter to find the rough cutting time and cutting depth in the medium speed cutting machining of the titanium alloy. It is found that the cutting machining heat are increased as the cutting depth, feed rate, cutting time and spindle speed are raised.

• Journal of International Society for Simulation Surgery
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• v.3 no.1
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• pp.16-21
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• 2016

Computed tomography (CT) can completely digitize the interior and the exterior of nearly any object without any destruction. Generally, the resolution for industrial CT is below a few microns. The industrial CT scanning, however, has a limitation because it requires long measuring and processing time. Whereas, 2D X-ray imaging is fast. In this paper, we propose a novel concept of 3D non-destructive inspection technique using the advantages of both micro-CT and dual X-ray images. After registering the master object’s CT data and the sample objects’ dual X-ray images, 3D non-destructive inspection is possible by analyzing the matching results. Calculation for the registration is accelerated by parallel computing using graphics processing unit (GPU).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.79-80
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• 2022

In December 2017, a fire at the Jecheon Sports Center caused 29 deaths and 40 injuries, and about 2 billion won in property damage. It is a facility used by unspecified people as a publicly used establishment with a piloti structure. The damage was expanded due to the ignition of combustible exterior materials, Lack of fire protection in horizontal and vertical penetrations. Although legislation has improved since the fire, it is not retroactively applied, increasing the risk of fire in existing buildings. Accordingly, it is necessary to examine the case of the Jecheon Sports Center fire and draw out the problems. In this study, the fire simulation results and the Jecheon Sports Center fire are comparatively analyzed and used as basic data for fire reduction measures in publicly used establishment. As a result of the fire simulation drive, in the case of the second floor, the room temperature exceeded the human life safety standard of 60 ℃ after about 700 seconds had passed. In the case of three floor, it is predicted that the indoor temperature will exceed about 350 ℃. and temporary complexation will occur in the indoor combustibles.