• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.103-111
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• 2018

This study examines the seismic failure of RC low-rise building structures having irregularities at the ground story during the 15 November 2017 Pohang, Korea, earthquake, $M_w=5.4$, which is the second strongest since the government began monitoring them in 1978 in South Korea. Some 2,000 private houses were damaged or destroyed in this earthquake. Particularly, serious damage to the piloti story of RC low-rise residential building structures of fewer than five stories was observed within 3 km of the epicenter with brittle shear failure of columns and walls due to severe torsional behavior. Buildings below six stories constructed before 2005 did not have to comply with seismic design requirements, so confinement detailing of columns and walls also led to inadequate performance. However, some buildings constructed after 2005 were damaged at the flexible side of the piloti story due to the high torsional irregularity. Based on these results, this study focuses on the problems of the seismic torsion design approach in current building codes.

• Journal of the Korean earth science society
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• v.39 no.4
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• pp.342-348
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• 2018

An earthquake of $M_L$ 5.8 hit the Gyeongju area on September 12, 2016. A sequence of foreshock-mainshock-aftershock of 588 events with equal to or greater than magnitude 1.5 occurred for six months in this area. Around ninety-nine percentage (98.8%) of the total energy was released intensively within a day, and about 80% of the total events took place within a month after the Gyeongju earthquake. The epicentral distribution of aftershocks of major events ($M_L$ 5.1, 5.8, 4.5, and 3.5) were elongated in the direction of $N30^{\circ}E$. They correlate well with the focal mechanism solution. These facts support the inference that the Gyeongju earthquakes occurred on a sub-parallel subsidiary fault of the Yangsan fault zone or on the linking damage zones between Deokcheon and Yangsan fault. During the last six years before the Gyeongju earthquake, there were few events within 10-km radius from the epicenter. This seismic gap area was filled with a sequence of the Gyeongju earthquakes. The b value for aftershock of the Gyeongju earthquakes is 1.09.

• Korean Institute of Interior Design Journal
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• v.16 no.2 s.61
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• pp.201-208
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• 2007

The $21^{st}$ century is the age of sentiment and image. As industrial development pushes the demands of consumers for various goods, the marketing patterns of these goods have individualized. They are expressions embedded with various meanings. Retail shops, now going beyond the practical purpose of display and sales of goods, enhancing brand images and establishing a consumer-oriented strategy, play a key role in reacting to and creating overall cultural issues. This study will analyze and investigate the Prada retail shop, which has distinguished its brand image and effectively promoted its identity through a sustained management strategy. The Prada retail shop has established an image of a cultural icon through cultural marketing. It suggests individuality and creativity along with diversity It reflects the basic concepts of cultural marketing, freedom of expression combined with information and high technology. The Prada building symbolizes the brand itself. To foster these kinds of retail shops, data and information based on continuous studies must be provided and shared, and also the systematic reinterpretation and the effective presentation of expressive trends in interior design needs to be studied on an ongoing basis.

• Geophysics and Geophysical Exploration
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• v.20 no.1
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• pp.49-55
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• 2017

Hypocentral depths of 103 aftershocks of the 12 September 2016 Gyeongju earthquake (ML 5.8) were inverted by epicentral relocation, using HYPO71 and HYPOINVERSE. From the comparison of seven models that reflect regional velocity structure in the southern Korean Peninsula, HYPO71 with linear weighting over the whole range showed less residuals than HYPOINVERSE for the model near the epicenter. Less uncertainties of focal depths were observed for the events with large magnitude and short range of the closest S-phase distance.

• Journal of Soil and Groundwater Environment
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• v.16 no.3
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• pp.38-47
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• 2011

Groundwater monitoring data from the National Groundwater Monitoring Stations, a total of 320 stations, were analyzed to identify the response of water level and quality to the Odaesan earthquake (M4.9) occurred in January 2007. Among the total of eight stations responded to the earthquake, five wells showed water-level decline, and in three wells, water level rose. In terms of recovery, water levels in four stations had recovered to the original level in five days, but not in the rest four wells. The magnitude of water-level change shows weak relations to the distance between the earthquake epicenter and the groundwater monitoring station. However, the relations to the transmissivities of monitored aquifer in the station with the groundwater change were not significant. To implement the earthquake monitoring system through the groundwater monitoring network, we still need to accumulate the long-term monitoring data and geostatistically analyze those with hydrogeological and tectonic factors.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.4
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• pp.33-46
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• 1999

In spite of 6.8 magnitude and the neighborhood of the epicenter, the steel moment frame survived after Northridge earthquake without collapse or casualties. However, following investigation revealed that there were severe damages at the column-weld interface of welded flange-bolted web (WFBW) steel moment connection, which was believed to be economic and safe from earthquakes based on experience and past tests. In this paper, this unexpected brittle fracture of the steel moment connection is explored using linear elastic fracture mechanics and post-Northridge tests. A method to predict the brittle fracture strength of the steel moment connection is proposed. Using this method, the failure mode of the WFBW connection and reduced beam section (RBS) connection are presented.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.305-312
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• 2003

Remote sensing can provide invisible information in addition to acquire wide-view image data from space. Synthetic Aperture Radar (SAR) transmits microwave to the earth from a satellite and collects the reflected echo from the surface. Interferometric processing of SAR data can detect the subtle land deformation. The information of the surface movement by SAR is useful to monitor the volcanic activity, extended subsidence of urbanized area and the prediction of the earthquake caused by crustal deformation, and it complements the conventional levelling and GPS technique. PSInSAR (Permanent Scatterers Interferometric SAR) is one of interferometric techniques to be applied to practical projects in Japan. In this paper, the projects of land deformation monitoring are shown after the explanations of the PSInSAR principle. Tokai earthquake risk assessment is the first example. PSInSAR detects the subduction of crustal deformation of the adjacent area of new assumed epicenter region of the Tokai Earthquake. The extended subsidence of the urbanized area was implemented by using Japanese satellite data i.e. JERS that has so much data the surrounding of Japan as the archive. We examine the relationship between the geological structure and settlement at Nohbi basin including Nagoya city.

• Asian Journal of Business Environment
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• v.10 no.4
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• pp.15-19
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• 2020

Purpose: This research aims to explore the level of air pollution in Jakarta, the epicenter of COVID-19 Pandemic in Indonesia and its surrounding provinces during the first month of the Pandemic. Research design, data and methodology: This study uses data, which have been obtained real time from API (Application Programming Interfaces) of air quality website. The measurements of Air Quality Index (AQI), temperature, humidity, and other factors from several cities and regencies in Indonesia were obtained eight times a day. The data collected have been analyzed using descriptive statistics and mapped using QGIS. Results: The finding of this study indicates that The Greater Jakarta Area experienced a decrease in pollutant levels, especially in the Bogor area. Nevertheless, some areas, such as the north Jakarta, have exhibited slow reduction. Furthermore, the regions with high COVID-19 confirmed cases have experienced a decline in AQI. Conclusions: The study concludes that the air quality of three provinces, Jakarta, Banten, and West Java, especially in cities located in the Jakarta Metropolitan Area during COVID-19 pandemic and large-scale social restrictions, is getting better. However, in some regions, the reduction of pollutant concentrations requires a longer time, as it was very high before the pandemic.

• The Journal of Engineering Geology
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• v.17 no.4
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• pp.673-680
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• 2007

The seismic source parameters of the Odaesan earthquake on 20 January 2007, including focal depth, focal mechanism, magnitude, and source characteristics, are analysed using seismic moment tensor inversion. The Green's function for different 3 crust models representing the southern Korean Peninsula are used. Final results show that the event, considering 6 seismic moment tensor elements, is caused by the typical strike slip fault with nearly NNE strike. The focal depth is estimated to be about 11km and 6 seismic moment tensor elements with 7.2% CLVD value shows typical double couple seismic source. The consistent characteristics of the strike and epicenter of the event with Odaesan fault imply that Odaesan earthquake is mainly caused by movement of the Odaesan fault.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.10a
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• pp.70-81
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• 1997

The intesity survery on the 26 June 1997 Kyeongju Earthquake whose magnitude is 4.3, has been made for 316 locations throughout southen park of Korean Peninsula, then we have investigated the intensities distribution of the earthquake. Because the earthquake was occurred during night time (03:50:23.19), the most people who live farather than about 200km from the epicenter did not feel the earthquake. Therefore, the intensities are estimated only from IV to V in this study. The iso-seismal intensity map shows that the shape of iso-seismal intensity is similar to the boundary of the Kyeongsang Basin. This phenomenon may indicates that the energy of the earthquake is trapped within the Kyeongsang Basin due to low velocity within the basin compared with the velocity outside of the basin. The travel time curves with 10 possible phases are used to identify the earquake records. The Pg and Sg phases are crearly shown in the records whose epicental distance is less than 60 km. The records of MUN and PCH stations located outside of the Kyiongsang Basin show different frequency compared with that of the other stations located within the Kyeongsang Basin.