• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.337-344
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• 2006

This paper is concerned with the simplified criterion given in ASCE 4-98, for determining whether soil-structure interaction (SSI) analysis is required for seismic response analysis of nuclear power plant structures. In this study, the criterion is evaluated for a couple of example structures including an existing nuclear power plant and the Hualien large-scale seismic test building. Forced vibration analysis and seismic response analysis are carried out using the simple stick model with soil springs and an elaborated SSI analytical model. From the numerical analyses, it is found that the criterion may not allow the fixed-base analysis for bedrock with shear wave velocity of greater than 1,100m/s which is a well-known criterion for a rock site. In addition, it is indicated that peak amplification as well as the peak broadening specified in NRC RG 1.122. shall be considered to include the effects of SSI.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.1
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• pp.40-49
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• 2004

In this paper, vibration response of aerial gas pipeline due to vehicle loads was quantitatively estimated through experiment and analysis in open cut construction site. The vehicle vibration of various construction machines causes serious effect to the aerial gas pipeline. The new vibration prediction equations presented in this study can estimate the vibration velocity response of the aerial gas pipeline. In the nitration prediction equations, the vehicle′s weight and traveling velocity, which are the sources of vibration, are combined into the term called, "scaled weight" Methods to reduce vibration were proposed in case the vibration velocity response of the gas pipeline exceeded the vibration criterion, using the vibration prediction equations presented in this study. One was to limit the vehicle′s traveling velocity and the other to install the isolation equipment. Both methods can be estimated quantitatively.

• The Journal of Engineering Geology
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• v.11 no.1
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• pp.25-35
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• 2001

For the ground resrxmse analysis, both in-situ and laboratory testing techniques such as downhole, SASW, resonant column and torsional shear tests were perlormed for Hong-Seong area. The grOlmd upper 30m is classified as SD since it has an average shear wave velocity as 209m/s. The response specLrums obtained by site-specific analyses generally satisfied the seismic code, but near the resonance period the motion was evaluated to be higher than the code.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.1012-1017
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• 2008

In this study, We examine closely the capacity spectrum method which a kind of displacement-based method evaluated by displacement of structure as an alternative to the load-based analysis method. The displacement-based method can easily review the strength of structure, seismic performance, ductility. Seismic performance by using capacity spectrum method is divided into design response spectrum and capacity spectrum. We can diagram design response spectrum by deciding the design seismic factor depending on performance target, site classification, seismic level, return period as UBC-97. Capacity spectrum is a load-displacement curve obtained by Push-over analysis considering the geometric parameter and the material parameter. We execute the seismic performance evaluation by using the capacity spectrum method to reinforced concrete pier which has been seismic design. As a result, We confirmed that there is a yield point and a ultimate point close by design response spectrum of UBC-97.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.7_spc
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• pp.527-536
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• 2016

This paper investigates seismic damage potential of recent September 12 M5.8 Gyeongju earthquake from diverse earthquake engineering perspectives using the accelerograms recorded at three stations near the epicenter. In time domain, strong motion durations are evaluated based on the accelerograms and compared with statistical averages of the ground motions with similar magnitude, epicentral distance and soil conditions, while Fourier analysis using FFT is performed to identify damaging frequency contents contained in the earthquake. Effective peak ground accelerations are evaluated from the calculated response spectra and compared with apparent peak ground accelerations and the design spectrum in KBC 2016. All these results are used to consistently explain the reason why most of seismic damage in the earthquake was concentrated on low-rise stiff buildings but not quite significant. In order to comparatively appraise the damage potential, the constant ductility spectrum constructed from the Gyeongju earthquake is compared with that of the well-known 1940 El Centro earthquake. Deconvolution analysis by using one accelerogram speculated to be recorded at a stiff soil site is also performed to estimate the soil profile conforming to the response spectrum characteristics. Finally, response history analysis for 39- and 61-story tall buildings is performed as a case study to explain significant building vibration felt on the upper floors of some tall buildings in Busan area during the Gyeongju earthquake. Seismic design and retrofit implications of M5.8 Gyeongju earthquake are summarized for further research efforts and improvements of relevant practice.

• Journal of the Korean GEO-environmental Society
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• v.21 no.1
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• pp.5-12
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• 2020

Vibration propagated from seismic sources has damping according to distance and amplification and reduction characteristic in different regions according to topography and geological structure. The vibration propagated from the seismic source to the bedrock is largely affected by the damping according to the separation distance, which can be simply estimated through the damping equation. However, it is important to grasp geological information by location because vibration estimation transmitted to the surface are affected by the natural period of the soil located above the bedrock. Geotechnical investigation data are needed to estimate the seismic intensity based on geological information. If there is no Vs profile, the standard penetration tests are mainly used to determine the soil parameters. The Integrated DB Center of National Geotechnical Information manages the geotechnical survey data performed on the domestic ground, and there is the standard penetration test information of 400,000 holes. In this study, the possibility of quantitation the amplification coefficient for each region was examined to calculated the physical interactive seismic intensity based on geotechnical information. At this time, the shear wave column diagram was generated from the SPT-N value and ground response analysis was performed in the target area. The site coefficients for each zone and the seismic intensity distribution for the seismic motion present a significant difference according to the analysis method and the regional setting.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.776-781
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• 2008

A ground heat exchanger in a GSHP system is an important unit that determines the thermal performance of a system and its initial cost. The Size and performance of this heat exchanger is highly dependent on the thermal properties. A proper design requires certain site-specific parameters, most importantly the ground effective thermal conductivity, the borehole thermal resistance and the undisturbed ground temperature. This paper is part of a research project aiming at constructing a database of these site-specific properties, especially ground effective thermal conductivity. The objective was to develop and evaluation method, and to provide this knowledge to design engineers. To achieve these goals, thermal response tests were conducted using a testing device at nearly 150 locations in Korea. The in-situ thermal response is the temperature development over time when a known heating load imposed, e.g. by circulating a heat carrier fluid through the test exchangers. The line-source model was then applied to the response test data because of its simplicity. From the data analysis, the range of ground effective thermal conductivity at various sites is $1.5{\sim}4.0\;W$/mK. The results also show that the ground effective thermal conductivity varies with grouting materials as well as regional geological conditions and groundwater flow.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.12
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• pp.4889-4908
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• 2020

With the advances in Information Technology (IT), users can download or stream copyrighted works, such as videos, music, and webtoons, at their convenience. Thus, the frequency of use of copyrighted works has increased. Consequently, the number of unauthorized copies and sharing of copyrighted works has also increased. Monitoring is being conducted on sites suspected of conducting copyright infringement activities to reduce copyright holders' damage due to unauthorized sharing of copyrighted works. However, suspected copyright infringement sites respond by changing their domains or blocking access requests. Although research has been conducted for improving the effectiveness of suspected copyright infringement site detection by defining suspected copyright infringement sites' response techniques as a lifecycle step, there is a paucity of studies on automation techniques for lifecycle detection. This has reduced the accuracy of lifecycle step detection on suspected copyright infringement sites, which change domains and lifecycle steps in a short period of time. Thus, in this paper, an automated detection technique for suspected copyright infringement sites is proposed for efficient detection and response to suspected copyright infringement sites. Using our proposed technique, the response to each lifecycle step can be effectively conducted by automatically detecting the lifecycle step.

• The Journal of Information Technology
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• v.6 no.3
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• pp.45-51
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• 2003

The purposes of this study were to identify Avatar benefits and characteristics of Avatar users. Avatars are imaginary characters that people use to represent themselves in the Cyber. The number of Netizens who want to consume avatars is increasing. It is necessary to understand about the consumption behavior of the Netizens who use Avatars. These data comes from Pollever Research Company in Korea on Oct. 2003. The factor Analysis of the data resulted in five factors that contribute to Avatar Benefits: uniqueness, response, assurance, self-expression, proxy satisfaction and affirmative. And we have found out meaningful themes, showing psychological experiences, purchasing strategies and repurchasing behavior of Avatars in the process of the consumption. The results showed a significant affect on each factor of the benefits and multiful regression analysis. Affirmative response was affected by self-esteem, fashion leadership and conspicuous value. So many Netizens were using unlimited purchasing coupons, exchanging Avatars and buying-selling-buying. Strategies for obtaining involved purchasing Avatars in order to get game points. The reason why Hangame site was No.1 of Avatar site in Korea. We have found out that Netizens needed to repurchase Avatars. Because they wanted to maintain positive psychological experiences in Avatar consumption.

• International Journal of Advanced Culture Technology
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• v.4 no.2
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• pp.7-18
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• 2016

The first D2C-era web-real variety show in Korea was broadcast via tvN of CJ E&M. The web-real variety program 'SinSeoYuGi' accumulated 54 million views, along with 50 million views at the Chinese portal site QQ. This study carries out an analysis using text mining that extracts portal site blogs, twitter page views and associative terms. In addition, this study derives viewers' response by extracting key words with opinion mining techniques that divide positive words, neutral words and negative words through customer sentiment analysis. It is found that the success factors of the web-real variety were reduced in appearance fees and production cost, harmony between actual cast members and scenario characters, mobile TV programing, and pre-roll advertising. It is expected that web-real variety broadcasting will increase in value as web contents in the future, and be established as a new genre with the job of 'technical marketer' growing as well.