• Proceedings of the KSRS Conference
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• v.2
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• pp.899-902
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• 2006

For a quick and accurate 3D modelling of a building, laser scanning data, digital maps, aerial photographs and satellite images should be fusioned. Moreover, library establishment according to a standard structure of a building and effective texturing method are required in order to determine the structure of a building. In this study, we made a standard library by categorizing Korean village forms and presented a model that can predict a structure of a building from a shape of the roof on an aerial photo image. We made an ortho image using the high-definition digital image and considerable amount of ground scanning point cloud and mapped this image. These methods enabled a more quick and accurate building modelling.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1105-1108
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• 2004

This paper describes the structural analysis result and load test result of accident EMU(Electric Multiple Units). Structural analysis and load test of EMU were performed for the criteria of safety assessment. Structural analysis using commercial I-DEAS software provided important information on the stress distribution and load transfer mechanisms as well as the amount of damages during rolling stock crash. The purpose of the load test is to evaluate a safety which carbody structure shall be considered fully sufficient rigidity so as to satisfy proper system function under maximum load and operating condition. The results have been used to provide the critical information for the criteria of safety assessment.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.3
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• pp.350-359
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• 2017

This paper presents a new holistic development approach for the carbon continuous-fiber composite frame of an automotive sunroof assembly. The original steel frame has been designed to get higher bending stiffness with its corrugated cross-sectional shape. The new approach uses the prepregs of a fast cure epoxy and PCM manufacturing processing. For higher productivity, the new frames feature a very simple plat cross sectional shape but achieve high bending stiffness through the laminate design. The sandwich structure with a PET foam core was presented. The frames were made of carbon UD laminae covered single carbon fabric on the outer surfaces. The fabrics provide torsional stiffness and also hold the carbon UD fibers floating in the low viscous epoxy resin of prepregs at the curing temperature during processing. The final product yields approximately 18 % savings in weight compared with the original.

• Journal of the Korean Institute of Rural Architecture
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• v.15 no.4
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• pp.35-42
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• 2013

The study aims to investigate general characteristics of Jae-sil from an architectural perspective by grasping location, deployment, structure, and plan composition based on existing inhabited conditions in Jeollabukdo. Results derived from the study are as follows. First, the location of Jae-sil is classified into mountainous and village types, and the two types showed a similar distribution. The village type showed the most distribution in the foot of a mountain in the rear of village, while the mountainous type is close to graveyard. The Jae-sil were mostly exposed to south, southeast, and southeast, which was not significantly different from residence. For deployment of the Jae-sil, a "二" shaped house, where main quarter and gated building are parallel located, can be common, indicating that additional attached building is less required. Second, for the platform out of structural components, coursed masonry was conducted by using natural rocks, and placed were a prop on the platform, first line on processed foot stone, and others on natural foot stone. For pillar, front line round columns, while others square columns. The binding type of the upper part of pillar is dominated by jangyeosujang and sorosujang. For wooden frame structure, 5ryangs were the most distributed, and out of these, 1goju 5ryang was the most generally used. For a roof part, it was composed with gambrel roof with single eave, and the roof was constructed by placing traditional Korean tile roof on the top. Third, for a size of Jae-sil out of plan composition, although the facade and the side of it were presented in a diverse manner, 4 facade rooms and 1.5 side rooms were the most frequently presented, and all Jae-sil were equipped with front ceremonial space. For spatial composition of Jae-sil, main floored hall is placed at the center, and each room is placed on the left and right side to secure space for ancestral rite for participants of it, and for a house with 5 rooms or more, it shows that main floored hall and rooms are weighted from side to side.

• Korean Journal of Heritage: History & Science
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• v.42 no.2
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• pp.134-153
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• 2009

This study is to examine closely the frame structure of buildings in the royal palace of Josen dynasty, focused on inner buildings of Changgyeonggung(昌慶宮) which is built in 19th century, through considering the member size of main structure and analyzing the slope of a rafter. The plans of a size on main member are as follows ; firstly, a length of the perimeter column was accorded with Gunggwolji(宮闕誌) and the planning size of interior column was shown to a Chon(a Korean inch, 寸) unit. The slope of long common rafter that is formed between the perimeter and interior columns was grasped with limits of a definite value. This is that the perimeter column is trimmed to a Chon unit, as Yeongchunheon(迎春軒), In the roof frame of Korean traditional timber architecture, the slope of rafter, first of all, is to decide the slope of long common rafter and then to decide a height of ridge piece settled whole height of a building. And it is regulated with position and height of a post so as to set up middle rafter. Especially, the slope of long common rafter, it is not to be decide through scale of a building but through a length of the perimeter column and composition of bracket structure. And in case middle rafter, the process of its slope is to devide the central bay on the side of a building into equality, and then to adjust position and length of a post.

• Structural Engineering and Mechanics
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• v.43 no.2
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• pp.179-197
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• 2012

This study presents the findings of the structural health monitoring and the real time system identification of one of the first large scale building instrumentations in Turkey for earthquake safety. Within this context, a thorough review of steps in the instrumentation, monitoring is presented and seismic performance evaluation of structures using both nonlinear pushover and nonlinear dynamic time history analysis is carried out. The sensor locations are determined using the optimal sensor placement techniques used in NASA for on orbit modal identification of large space structures. System identification is carried out via the stochastic subspace technique. The results of the study show that under ambient vibrations, stocky buildings can be substantially stiffer than what is predicted by the finite element models due to the presence of a large number of partitioning walls. However, in a severe earthquake, it will not be safe to rely on this resistance due to the fact that once the partitioning walls crack, the bare frame contributes to the lateral stiffness of the building alone. Consequently, the periods obtained from system identification will be closer to those obtained from the FE analysis. A technique to control the validity of the proportional damping assumption is employed that checks the presence of phase difference in displacements of different stories obtained from band pass filtered records and it is confirmed that the "proportional damping assumption" is valid for this structure. Two different techniques are implemented for identifying the influence of the soil structure interaction. The first technique uses the transfer function between the roof and the basement in both directions. The second technique uses a pre-whitening filter on the data obtained from both the basement and the roof. Subsequently the impulse response function is computed from the scaled cross correlation between the input and the output. The overall results showed that the structure will satisfy the life safety performance level in a future earthquake but some soil structure interaction effects should be expected in the North South direction.

• Journal of the Earthquake Engineering Society of Korea
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• v.21 no.6
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• pp.311-322
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• 2017

In this study, the seismic performance of concrete-steel composite moment frame structures equipped with seismic retrofitting systems such as seismic reinforcement, base isolators, and bracing members, which are typical earthquake damage mitigation systems, is evaluated through nonlinear dynamic analyses. A total of five frame models were designed and each frame model was developed for numerical analyses. A total of 80 ground acceleration data were used to perform the nonlinear dynamic analysis to measure ground shear force and roof displacement, and to evaluate the behavioral performance of each frame model by measuring inter-story drift ratios. The analysis results indicate that the retrofitting device of the base isolator make a significant contribution to generating relatively larger absolute displacement than other devices due to flexibility provided to interface between ground and column base. However, the occurrence of the inter-story drift ratio, which is a relative displacement that can detect the damage of the structure, is relatively small compared with other models. On the other hand, the seismic reinforced frame model enhanced with the steel plate at the lower part of the column was found to be the least efficient.

• Earthquakes and Structures
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• v.17 no.6
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• pp.599-609
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• 2019

After an earthquake, a quick seismic assessment of a structure can facilitate the recovery of operations, and consequently, improve structural resilience. Especially for facilities that play a key role in rescue or refuge efforts (e.g., hospitals and power facilities), or even economically important facilities (e.g., high-tech factories and financial centers), immediately resuming operations after disruptions resulting from an earthquake is critical. Therefore, this study proposes a prompt post-earthquake seismic evaluation method that uses displacement and acceleration measurements taken from real structural responses that resulted during an earthquake. With a prepared pre-earthquake capacity curve of a structure, the residual seismic capacity can be estimated using the residual roof drift ratio and stiffness. The proposed method was verified using a 6-story steel frame structure on a shaking table. The structure was damaged during a moderate earthquake, after which it collapsed completely during a severe earthquake. According to the experimental results, a reasonable estimation of the residual seismic capacity of structures can be performed using the proposed post-earthquake seismic evaluation method.

• Wind and Structures
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• v.12 no.2
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• pp.89-101
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• 2009

The Monte Carlo procedure was used to simulate wind load effects on a light-frame low-rise structure of irregular shape and a main wind force resisting system. Two analytical models were studied: rigid-beam and rigid-plate models. The models assumed that roof diaphragms were rigid beam or rigid plate and shear walls controlled system behavior and failure. The parameters defining wall stiffness, including imperfections, were random and included wall stiffness, wall capacity and yield displacements. The effect of openings was included in the simulation via a set of discrete multipliers with uniform distribution. One and two-story buildings were analyzed and the models can be expanded into multiple-floor structures provided that the assumptions made in this paper are not violated.

• Steel and Composite Structures
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• v.26 no.5
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• pp.549-556
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• 2018

Progressive building collapse occurs when failure of a structural component leads to the failure and collapse of surrounding members, possibly promoting additional failure. Global system collapse will occur if the damaged system is unable to reach a new static equilibrium configuration. The most common type of primary failure which led to the progressive collapse phenomenon, is the sudden removal of a column by various factors. In this study, a method is proposed to prevent progressive collapse phenomena in structures subjected to removal of a single column. A vierendeel peripheral frame at roof level is used to redistribute the removed column's load on other columns of the structure. For analysis, quasi-static approach is used which considers various load combinations. This method, while economically affordable is easily applicable (also for new structures as well as for existing structures and without causing damage to their architectural requirements). Special emphasis is focused on the evolution of vertical displacements of column removal point. Even though additional stresses and displacements are experienced by removal of a structural load bearing column, the proposed method considerably reduces the displacement at the mentioned point and prevents the collapse of the structural frame.