• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.6
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• pp.707-714
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• 2011

The inter-story drift ratio is used to evaluate the damage of buildings by the earthquake. This is known that as the inter-story drift ratio decreases, the seismic damage decreases. Although to reduce the inter-story drift ratio is the important issue in the seismic design, no practical inter-story drift design method has bean developed. This study presents an optimal inter-story drift design method to improve the seismic performance of the steel moment frames using the resizing algorithm. The objective function of the proposed method is to minimize the differences of the inter-story drift ratios so that the inter-story drift ratios of the building could be distributed evenly and be reduced. Because this method redesigns the sectional properties of structural members base on the displacement participation factor calculated by the unit-load method, this can improve the seismic performance of the structure without the iterative structural analysis. The efficiency of this algorithm was demonstrated by the application to steel moment frames.

• Structural Engineering and Mechanics
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• v.76 no.3
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• pp.421-433
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• 2020

Masonry infills are normally considered as non-structural elements in design practice, therefore, the interaction between the bounding frame and the strength contribution of masonry infills is commonly ignored in the seismic analysis work of the RC frames. However, a number of typical RC frames with irregular distributed masonry infills have suffered from undesirable weak-story failure in major earthquakes, which indicates that ignoring the influence of masonry infills may cause great seismic collapse risk of RC frames. This paper presented the investigation on the risk of seismic collapse of RC frames with irregularly distributed masonry infills through a large number of nonlinear time history analyses (NTHAs). Based on the results of NTHAs, seismic fragility curves were developed for RC frames with various distribution patterns of masonry infills. It was found that the existence of masonry infills generally reduces the collapse risk of the RC frames under both frequent happened and very strong earthquakes, however, the severe irregular distribution of masonry infills, such as open ground story scenario, results in great risk of forming a weak story failure. The strong-column weak-beam (SCWB) ratio has been widely adopted in major seismic design codes to control the potential of weak story failures, where a SCWB ratio value about 1.2 is generally accepted as the lower limit. In this study, the effect of SCWB ratio on inter-story drift distribution was also parametrically investigated. It showed that improving the SCWB ratio of the RC frames with irregularly distributed masonry infills can reduce inter-story drift concentration index under earthquakes, therefore, prevent weak story failures. To achieve the same drift concentration index limit of the bare RC frame with SCWB ratio of about 1.2, which is specified in ACI318-14, the SCWB ratio of masonry-infilled RC frames should be no less than 1.5. For the open ground story scenario, this value can be as high as 1.8.

• Earthquakes and Structures
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• v.17 no.2
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• pp.163-173
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• 2019

For Special Concentrically Braced Frame (SCBF), it is common that the damage concentrates at a certain story instead of spreading over all stories. Once the damage occurs, the soft-story mechanism is likely to take place and possibly to result in the failure of the whole system with more damage accumulation. In this study, we use a strongback column which is an additional structural component extending along the height of the building, to redistribute the excessive deformation of SCBF and activate more structural members to dissipate energy and thus avoid damage concentration and improve the seismic performance of SCBF. We tested one-third-scaled, three-story, double-story X SCBF specimens with static cyclic loading procedure. Three specimens, namely S73, S42 and S0, which represent different combinations of stiffness and strength factors ${\alpha}$ and ${\beta}$ for the strongback columns, were designed based on results of numerical simulations. Specimens S73 and S42 were the specimens with the strongback columns, and S0 is the specimen without the strongback column. Test results show that the deformation distribution of Specimen S73 is more uniform and more brace members in three stories perform nonlinearly. Comparing Drift Concentration Factor (DCF), we can observe 29% and 11% improvement in Specimen S73 and S42, respectively. This improvement increases the nonlinear demand of the third-story braces and reduces that of the first-story braces where the demand used to be excessive, and, therefore, postpones the rupture of the first-story braces and enhances the ductility and energy dissipation capacity of the whole SCBF system.

• Structural Engineering and Mechanics
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• v.47 no.6
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• pp.791-818
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• 2013

The seismic performance of reinforced concrete (RC) frame structures with irregularities leading to soft first floor is studied using capacity assessment procedures. The soft first story effect is investigated for the cases: (i) slab-column connections without beams at the first floor, (ii) tall first story height and (iii) pilotis type building (open ground story). The effects of the first floor irregularity on the RC frame structure performance stages at global and local level (limit states) are investigated. Assessment based on the Capacity Spectrum Method (ATC-40) and on the Coefficient Method (FEMA 356) is also examined. Results in terms of failure modes, capacity curves, interstory drifts, ductility requirements and infills behaviour are presented. From the results it can be deduced that the global capacity of the structures is decreased due to the considered first floor morphology irregularities in comparison to the capacities of the regular structure. An increase of the demands for interstory drift is observed at the first floor level due to the considered irregularities while the open ground floor structure (pilotis type) led to even higher values of interstory drift demands at the first story. In the cases of tall first story and slab-column connections without beams soft-story mechanisms have also been observed at the first floor. Rotational criteria (EC8-part3) showed that the structure with slab-column connections without beams exhibited the most critical response.

• Journal of Environmental Science International
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• v.14 no.5
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• pp.473-480
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• 2005

The cost of the construction and management of new apartment buildings was evaluated using a monetary analysis and an emergy concept to provide a new perspective regarding the housing policy of Korea. The systems of analyses were typical apartment buildings with an area of $76.03m^2$ per household in Korea built on the same size of land area. Three apartment buildings with different stories were evaluated and compared; 5-story, 15-story, and 20-story apartment buildings. The durable years of those apartments were assumed to be 40 years. The total cost of the construction and management of an apartment building was divided into three categories of construction, land purchase, and management. A 20-story apartment showed the highest cost and a 15-story apartment the lowest in the monetary cost analysis. In contrast, the emergy evaluation revealed a different pattern in the cost of construction and management, the cost increasing from a 5-story apartment to a 20-story one. This means that the higher the apartment constructed, the greater the cost in terms of real wealth. This result suggests that new evaluation methodologies like the emergy analysis should be used together with the monetary analysis to provide better insights on the national housing policy.

• The Mathematical Education
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• v.52 no.1
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• pp.65-82
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• 2013

This study has to do with storytelling. In this study, analyzed the domestic and international academic literature and scientific papers. The purpose of this study is to provide the meaningful basic material on mathematics education for the development of storytelling lesson model and teaching material. First, we analyze the causes and background storytelling appeared. The psychologists found that the human cognition's structure consists of a narrative system. And, We realize that the problem 'How will attract the attention of the students in math class' will be solved by storytelling. Second, the means of storytelling about the educational value and benefits were discussed in Mathematics Education. The story has a powerful force in the delivery of mathematical content. And, the story has strong power, led to feelings of students receiving transfer mathematical content. Finally, examined the characteristics of the psychology of learning in mathematics education by storytelling. We were studied about internal and external story. And, we studies on storytelling as the mediator, story as the knowledge transfer, story as the problem-solving process, story as the script.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.61-67
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• 2020

The game has several genres. Actions, RPGs, FPS, and simulations are diverse, and the game that flows around the story is a game genre that feels like watching a movie on the other. Internet game broadcasters can be thought of as playing a movie in a movie theater when they broadcast a story-type game. The difference with the movie theater is that you can get involved in the story by showing your play directly to viewers. As a broadcasting material, story-type games are a good means, but the fact that the story is published on the Internet in terms of game publishers can have a negative impact on sales revenue as viewers can enjoy the story without purchasing the game. The purpose of this study is to analyze the coordination status between producers and internet broadcasters for story-type games that could be copyrighted and suggest ways to move forward.

• Structural Engineering and Mechanics
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• v.87 no.5
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• pp.405-418
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• 2023

This study focused on the effectiveness of seismic isolation technique in case of a reinforced concrete structure with soft story defined as the stiffness irregularity between adjacent stories. In this context, a seismically isolated 3-story reinforced concrete structure was analyzed by gradually increasing the first story height (3.0, 4.5, and 6.0 m). The seismic isolation system of the structure is assumed to be composed of lead rubber bearings (LRB). In the analyses, isolators were modeled by both deteriorating (temperature-dependent analyses) and non-deteriorating (bounding analyses) hysteretic representations. The deterioration in strength of isolator is due to temperature rise in the lead core during cyclic motion. The ground motion pairs used in bi-directional nonlinear dynamic analyses were selected and scaled according to codified procedures. In the analyses, different isolation periods (Tiso) and characteristic strength to weight ratios (Q/W) were considered in order to determine the sensitivity of structural response to the isolator properties. Response quantities under consideration are floor accelerations, and interstory drift ratios. Analyses results are compared for both hysteretic representations of LRBs. Results are also used to assess the significance of the ratio between the horizontal stiffnesses of soft story and isolation system. It is revealed that seismic isolation is a viable method to reduce structural damage in structures with soft story.

• International Journal of Advanced Culture Technology
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• v.8 no.4
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• pp.25-32
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• 2020

Currently, Korean museums use gamification in addition to various viewing methods, such as video and VR/AR. However, museums using museum gamification are still progressing to a special program level. The purpose of this paper is to make the contents of the museum easy to understand and to give the viewers fun. This paper goes beyond the existing museum gamification and proposes a museum story gamification that combines story elements with gamification. This proposal system collects information from each museum in cooperation with museums, art galleries, and exhibition halls and proceeds with related story games. Museum Story Gamification provides related stories according to the theme of the museum and allows viewers to select their own stories. Also, based on the story, you can directly select the difficulty level that suits you and play a personalized game. Unlike the general museum program, the methodology proposed in this paper allows visitors to experience the museum with various story contents. In addition, it will contribute to the development and implementation of programs with gamification in other tourism fields as well as museums.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.1
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• pp.51-58
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• 2021

As vertical extension remodeling policy was implemented in 2014, Safety Inspection Manual was established to ensure structural safety during the vertical extension remodeling. In the manual, the story weight for capability evaluation was based on the Safety Inspection Manual for Reconstruction. Although capability evaluation in the vertical extension remodeling is more important than reconstruction, engineering basis for the story weight is insufficient. Therefore it is necessary to improve the method of calculating the story weight. In this study, story importance and story weight were defined through the case analysis of capability evaluation in order to provide engineering basis for story weight. Also, new story weight equation was presented considering the load-bearing ratio of structural members.