• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.1
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• pp.11-20
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• 2008

In probabilistic seismic analysis of nonlinear structural system, dynamic analysis is performed to obtain the distribution of the response estimate using input ground motion time histories which correspond to a given seismic hazard level. This study investigates the differences in the distribution of the responses and the failure probability according to input ground motion models. Two types of input ground motion models are considered: real earthquake records scaled to specified intensity level and artificial input ground motion fitted to design response spectrum. Simulation results fir a nonlinear SDOF system demonstrate that the spectrum matched input ground motion produces larger failure probability than those of scaled input ground motion due to biased responses. Such tendency is more remarkable in the site of soft soil conditions. Analysis results show that such difference of failure probability is due to the conservative estimation of design response spectrum in the range of long period of ground motion.

• Journal of the Geological Society of Korea
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• v.54 no.6
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• pp.657-675
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• 2018

The apparent thickening of the subducting slab in the shallow lower mantle has been attributed to slab buckling. However, the scaling laws have not been quantitatively evaluated for the buckling behavior of the subducting slab when phase transformations are considered. Thus, two-dimensional dynamic subduction experiments are formulated to evaluate the effect of phase transformations on the buckling behavior of the subducting slab. The model calculations show that the phase transformation from olivine to wadsleyite at a depth of 410 km plays an important role in the development of slab buckling; increased slab pull due to the endothermic phase transformation accelerates slab sinking in the upper mantle and the subducting slab reaches the lower mantle in a shorter time than that of the experiments without the phase transformation. However, the phase transformation from ringwoodite to perovskite plus $magnesiow{\ddot{u}}stite$ at a depth of 660 km retards slab sinking into the lower mantle and the subducting slab tends to be accumulated in the transformation (transition) zone. Buckling analyses show that the scaling laws predict the buckling amplitude and period of the subducting slab with small relative errors even if the phase transformations are considered. The universal phenomenon of the slab buckling can explain apparent slab thickening in the shallow lower mantle and transformation zone under the subduction zones such as Java-Sunda and Northeast Japan. In addition, the buckling behavior of the subducting slab may be related to the periodic compressions and extensions in the Cretaceous Gyeongsang basin.

• The Southeast Asian review
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• v.21 no.1
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• pp.137-184
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• 2011

This article is aimed at understanding the political narratives represented in the National Museum of Indonesia. Starting initially as a colonial museum, the National Museum of Indonesia functioned as a useful tool for the Dutch colonial force to fuel its imaginations of the colonial territory and the people within it. The Dutch used the cultural display to advertize its benevolent colonial rule. All the while, the museum also inevitably reflected orientalism on the people and the culture of the colony. The republic of Indonesia inherited the colonial museum's practices and its display patterns. The business surrounding the museum also played a key role in the newly-born nation-state laying out a future for its redefined territory and people. Thus, what the colonial force imagined for the colonial territory through the study of museum displays was rather directly transferred to the republic without serious consideration of the decolonization process. Four main characteristics have been seen in the museum displays. The first is an emphasis on the glorious Hindu-Buddha history, from which numerous temples, statues, and jewelry have been found. Secondly, the Islamic period, which spanned between the Hindu-Buddha times to the colonial era, has almost completely been eliminated from the display. Third, the colonial era has been depicted as the time of Europe's exportation of scientific tools and adaption of sophisticated living patterns. Fourth, the images of ethnic groups were represented as being stagnant without reflecting any challenges and responses that these groups had faced throughout history. Looking at these display patterns, it can be concluded that all the dynamic internal developments and anti-colonial resistance that took place during the Islamic and Colonial Era have simply not been represented in the museum display. These display patterns do not reflect the real history or culture of the archipelago. Two considerations are thought to have influenced the neglecting of social realities in the display. The first of which is the Dutch's and Republic's apprehension over the possible political upheaval by the Islamic forces. Yet, more fundamentally, cultural displays themselves are distinct from historical education in that the former pays more attention to business ideas with an aim to attract tourists rather than to project objective historical knowledge. Thus, in cultural displays, objects which work to stimulate fantasies and spur curiosity on archipelagic culture tend to be selected and emphasized. In this process, historical objectivity is sometimes considered less vital. Cultural displays are set up to create more appealing narratives for viewers. Therefore, if a narrative loses its luster, it will be replaced by another flashy and newly-resurrected memory. This fact reveals that museums, as transmitters of historical knowledge, have a certain degree of limitation in playing their role.

• Journal of Convergence for Information Technology
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• v.8 no.4
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• pp.73-80
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• 2018

The purpose of this study was to investigate the effect of motion-based dance game on static and dynamic balance in elderly women. The participants were randomly divided into 2 group, Motion Based dance game group(n=10), control group(n=10). After they were divided into an Motion Based dance game group and a control group the Motion Based dance game group participated in six-week period of time, three times a week, 60 minutes each, and the control group didn't exercise outside of their daily lives. To evaluated the balance ability of exercise, it was evaluated by using Berg Balance Scale(BBS), Functional Reach Test(FRT), Timed Up and Go test(TUG). The data was analysis using a paired t-test and independent t-test to determine the statistical significance. The results of this study between BBS, FRT, TUG and Motion Based dance game group had statistically significant difference rather than control group(p<.05). In conclusion, the Motion based Dance Game showed improvement on the balance ability in the elderly. Regular maintenance of the Dance Game "Dance Central" program for the elderly will assistance improve the balance. Consequently, studies on the development of dance games suitable for the elderly are believed to be necessary.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.94-101
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• 2019

Most of the existing rail structures have undergone a lot of aging since a considerable period of time has passed from completion. In particular, among existing railway bridges, many of the plate girder bridges are older bridges that have lived 40 to 60 years or more. Since the treadmill is directly connected to the girder without the ballast, the running load of the vehicle is directly transmitted to the bridge. Therefore, the shock and noise applied to the bridge are larger than those of the ballast bridge, and the dynamic shock and vibration are also relatively large. Therefore, it is very urgent to develop appropriate maintenance, repair and reinforcement technology for existing steel plate bridge. In this study, the authors introduced the characteristics of embedded rail (ERS) developed for improving the performance of the existing plate girder bridge and the techniques solving the vibration and noise problems. In order to evaluate the vibration and noise reduction performance of ERS, a non-ballast plate girder bridge with 5m length of sleepers installed and a plate girder bridge with ERS were fabricated. And, then, the vibration response generated under the same excitation condition was measured and analyzed. Also, the radiated noise analysis was performed using the vibration response data obtained from the experiment as the input data of the acoustic analysis model. As a result of experiments and analyses, it was confirmed that the plate girder bridge's vibration using ERS was reduced by 15.0~18.8dB and the average noise was reduced by 7.7dB(A) more than the non-ballast bridge.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.2
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• pp.75-86
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• 2019

The biggest obstacle in the nuclear power generation is the high level radioactive waste such as the spent nuclear fuel. High level radioactivities and generated heat make the safe treatment of the spent nuclear fuel very difficult. Nowadays, the only treatment method is a deep geological disposal technology. This paper treats the structural safe design problem of the spent nuclear fuel disposal canister which is one of the core technologies of the deep geological disposal technology. Especially, this paper executed the nonlinear structural analysis for the stresses and deformations occurring in the canister due to the impulsive force applied to the spent nuclear fuel disposal canister in the case of an accidental drop and ground impact event from the transportation vehicle in the repository. The main content of the analysis is about that the impulsive force is obtained using the commercial rigid body dynamic analysis computer code, RecurDyn, and the stress and deformation caused by this impulsive force are obtained using the commercial finite element static structural analysis computer code, NISA. The analysis results show that large stresses and deformations may occur in the canister, especially in the rid or the bottom of the canister, due to the impulsive force occurring during the collision impact period.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.90-105
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• 2021

The shape of the roof is very important, as it determines the beauty of the exterior of Korean wooden architecture. In particular, the curve of the eaves is the most representative of the characteristics of Korean wooden architecture. Rafters and buyeon (浮椽), flying rafters, create curves for the eaves, and buyeon in particular makes the roof lighter and more dynamic. Although the function and role of buyeon are already known, nothing is yet clear about the beginning of its use in Korean ancient architecture. Accordingly, the purpose of this study is to determine when buyeon was first used in Korean architecture. To this end, I examined various records, buildings, remains, and artifacts that have architectural shapes in Korea, China, and Japan. The results are summarized as follows. First, the use of buyeon in China appears during the Northern Qi Dynasty (北齊) in the mid-6th century, but became common in the 7th century during the Tang (唐) Dynasty. Second, the use buyeon in Japan appears in the mid-8th century, when the capital was relocated from Asuka (飛鳥) to Nara (奈良). It corresponds with the time that Japan began importing Chinese culture directly. Third, the use of buyeon in Korea may have been introduced to Baekje from China in the mid-6th century, but it was not common. It is believed that it became common after active exchanges with the Tang Dynasty during the Unified Silla Period in the mid-7th century.

• The Journal of the Korean Institute of Forest Recreation
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• v.22 no.4
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• pp.1-9
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• 2018

This study aimed to improve the quality of forest healing program through analyses of the program activities given at National Healing Forest and surveys conducted by Korea Forest Service. 99 DB data of the healing forest that were surveyed by KFS (August 2015~April 2016) were collected in order to affirm the activities. We analysed DB based on the format of the survey by target, 6 healing factors, location, season, time periods, operation hours and multifaceted evaluation. The results showed that the activities in the forest healing program targeted general public and the factor that was considered the most was psychotherapy factor. Healing forest trails were used as a location, spring, summer and fall as season, morning and afternoon as time period for the majority of the activities. The running time was 60 minutes. The multifaceted evaluation revealed that dynamic activities were preferred the most in development of programs. According to the results of the forest healing programs, it seems to be critical to enhance forest healing instructors' diversified professionalism. However, this will only be achievable once further investigations regarding forest healing effects by types of illnesses are conducted and provide solid foundation for such professionalism.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1323-1337
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• 2020

GEO-KOMPSAT-2A AMI (Advanced Meteorological Imager) radiometric calibration evaluation is an essential element not only for functional and performance verification of the payload but for the quality of the sensor data. AMI instrument consists of six reflective channels and ten thermal infrared ones. One of the key parameters representing radiometric properties of the sensor is a SNR (Signal-to-Noise Ratio) for the reflective channels and a NEdT (Noise Equivalent delta Temperature) for the IR ones respectively. Other important radiometric calibration parameters are a dynamic range and a gain value related with the responsivity of detectors. To verify major radiometric calibration performance of AMI, an offline radiometric evaluation tool was developed separately with a real-time AMI data processing system. Using the evaluation tool, validation activities were carried out during the GEO-KOMPSAT-2A In-Orbit Test period. The results from the evaluation tool were cross checked with those of the HARRIS, which is the AMI payload vendor. AMI radiometric evaluation activities were conducted through three phases for both sides (Side 1 and Side 2) of AMI payload. Results showed that performances of the key radiometric properties were outstanding with respect to the radiometric requirements of the payload. The effectiveness of the evaluation tool was verified as well.

• Journal of Korea Entertainment Industry Association
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• v.14 no.1
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• pp.17-25
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• 2020

The purpose of this study was to examine the effects of coordinative locomotor training (CLT) program on the balance for the promotion of life care of elderly obese women. Ten participants of elderly obese women who were able to walk independently without surgery experience of lumbar, hip or knee joint within the past year were recruited and under went the pretest, CLT (20 sessions), followed by the post-test. The test included BMI test using In-body, joint kinematics using myoVIDEO, muscle activation using surface EMG test (erector spinae (ER), external oblique abdominalis (EO), quadriceps femoris (Quad), hamstring muscle (Ham)) and balance tests including dynamic balance test using forced treadmill, Berg balance scale (BBS) and timed up go (TUG). The CLT program was conducted 60 minutes a day, 5 days a week, over 4 weeks period. As a result of this study, The the trunk and hip joints kinematics during the stance and swing phases of gait were a statistical significance levels were set at p <0.05. The ER and EO muscle activation were significantly improved after intervention (p <0.05). The length of gait line and single support line of change of center of pressure (COP) were significantly increased after intervention (p <0.05). The BBS and TUG were also significantly enhanced after intervention (p <0.05). The results of this study showed that CLT program for the improvement of life care had significant effects on improving postural instability, muscle weakness, reduced balance ability and falling risk of obese elderly women. Therefore, it is recommended to apply CLT program to improve life-care through improving balance ability and preventing fall of obese elderly women.