• Earthquakes and Structures
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• v.18 no.2
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• pp.163-170
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• 2020

Floor acceleration plays a major role in the seismic design of nonstructural components and equipment supported by structures. Large floor acceleration may cause structural damage to or even collapse of buildings. For precision instruments in high-tech factories, even small floor accelerations can cause considerable damage in this study. Six P-wave parameters, namely the peak measurement of acceleration, peak measurement of velocity, peak measurement of displacement, effective predominant period, integral of squared velocity, and cumulative absolute velocity, were estimated from the first 3 s of a vertical ground acceleration time history. Subsequently, a new predictive algorithm was developed, which utilizes the aforementioned parameters with the floor height and fundamental period of the structure as the new inputs of a support vector regression model. Representative earthquakes, which were recorded by the Structure Strong Earthquake Monitoring System of the Central Weather Bureau in Taiwan from 1992 to 2016, were used to construct the support vector regression model for predicting the peak floor acceleration (PFA) of each floor. The results indicated that the accuracy of the predicted PFA, which was defined as a PFA within a one-level difference from the measured PFA on Taiwan's seismic intensity scale, was 96.96%. The proposed system can be integrated into the existing earthquake early warning system to provide complete protection to life and the economy.

• Journal of the Korea Society of Computer and Information
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• v.13 no.6
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• pp.59-68
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• 2008

In this paper, we propose a method for selecting meaningful event packets from which can receive before anything else from seismograph according to allotted priority and estimate epicenter using selected packets. Event packets which received from each station will be evaluated with their onset time, signal period and SNR by statistical method and will be selected packets related with real earthquake's P-wave. And estimated epicenters using by 'Application of epicenter estimation using first P arrivals'. With local earthquakes occurred in 2007 were announced by KMA, collected event packets on earthquake happened date and selected p-wave related packets and estimated epicenter. After result of experiment, if an earthquake occurred within seismic networks, can estimate epicenter with small misfits just after event packets arrived from above 4 stations. Considering average distance of each station, in case of using all stations' data include other organization, can estimate and alert rapidly. It show this method is useful when construct a local earthquake early warning system later.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.09a
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• pp.19-27
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• 2002

The four agencies in Korea - KMA, KIGAM, KEPRI, and KINS - have been operating their own seismic network for many years. In this study we have developed an integrated seismic system named KISS (Korea Integrated Seismic System), which is very similar to LISS (Live Internet Seismic Server) of Albuquerque Seismological Laboratory. Through KISS we could share all the earthquake data observed by those organizations in near real time. This research result will lead to provide the opportunity to use all seismic information of the earthquakes around Korean peninsula. And KISS will make us enable to do systematic researches, such as study on focal mechanisms of earthquakes around Korean peninsula, seismic design, earthquake prediction, etc. KISS will be used in developing an Early Earthquake Warning System like TriNet in Southern California, USA so as to minimize seismic hazard.

• Proceedings of the KSRS Conference
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• v.2
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• pp.827-830
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• 2006

The tsunami from the megathrust earthquake magnitude 9.3 on 26 December 2004 is the largest tsunami the world has known in over forty years. This tsunami destructively attacked 13 countries around Indian Ocean with at least 230,000 fatalities, displaced people 2,089,883 and 1.5 million people who lost their livelihoods. The ratio of women and children killed to men is 3 to 1. The total damage costs US$ 10.73 billion and rebuilding costs US$ 10.375 billion. The tsunami's death toll could have been drastically reduced, if the warning was disseminated quickly and effectively to the coastal dwellers along the Indian Ocean rim. With a warning system in Indian Ocean similar to that operating in the Pacific Ocean since 1965, it would have been possible to warn, evacuate and save countless lives. The best tribute we can pay to all who perished or suffered in this disaster is to heed its powerful lessons. UNESCO/IOC have put their tremendous effort on better disaster preparedness, functional early warning systems and realistic arrangements to cope with tsunami disaster. They organized ICG/IOTWS (Indian Ocean Tsunami Warning System) and the third of this meeting is held in Bali, Indonesia during $31^{st}$ July to $4^{th}$ August 2006. A US$ 53 million interim warning system using tidal gauges and undersea sensors is nearing completion in the Indian Ocean with the assistance from IOC. The tsunami warning depends strictly on an early detection of a tsunami (wave) perturbation in the ocean itself. It does not and cannot depend on seismological information alone. In the case of 26 December 2004 tsunami when the NOAA/PMEL DART (Deep-ocean Assessment and Reporting of Tsunami) system has not been deployed, the initialized input of sea surface perturbation for the MOST (Method Of Splitting Tsunami) model was from the tsunamigenic-earthquake source model. It is the first time that the satellite altimeters can detect the signal of tsunami wave in the Bay of Bengal and was used to validate the output from the MOST model in the deep ocean. In the case of Thailand, the inundation part of the MOST model was run from Sumatra 2004 for inundation mapping purposes. The medium and high resolution satellite data were used to assess the degree of the damage from Indian Ocean tsunami of 2004 with NDVI classification at 6 provinces on the Andaman seacoast of Thailand. With the tide-gauge station data, run-up surveys, bathymetry and coastal topography data and land-use classification from satellite imageries, we can use these information for coastal zone management on evacuation plan and construction code.

• Proceedings of the KSEG Conference
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• 2005.04a
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• pp.107-110
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• 2005

The seismological observation of Korea began in 1905, and has been run with continuous earthquake network of observation, expanding to the advanced country, but still has some problems in accuracy and speed for report. There are many problems to issue the early warning system for earthquakes and Tsunami in the East Sea because most events in the East Sea occur outside the seismic network. Therefore multi-waveform data conversion and composition from the surrounding countries such as Korea, Japan and Far East Russia are requested in order to more accurate determination of earthquake parameters. We used FESNET(Far East Seismic Network) technology to analyze 2004 May 29th Uljin Earthquake and 2005 March 20th Japanese Fukuoka Earthquake in this research, using the data of KMA, Japan stations and IRIS(4 station).

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.2
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• pp.29-38
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• 2010

It often occur to nature disaster that like earthquake, typhoon, etc. around KOREA. A Haiti and Chile also metropolitan area of KOREA occur earthquake. in result, People think of nature disaster. Structures of present age are easily affected by nature disaster. So we are important that warn of dangerous situation as soon as possible. On this study, I introduce Integrated monitoring system that administrator check a event as early. I develop Monitoring System using SMS(Short Message Service). Administrator always monitor structure on real-time using mobile web-page. As Administrator using mobile device like PDA, Administrator always monitor structure. As using this system, Damage of nature disaster is minimized and is prevented post damage.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.11a
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• pp.92-94
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• 2013

최근 기상청에서는 대국민 지진조기경보 전달매체를 통하여 지진 관측 후 지진속보 혹은 지진통보 시간을 획기적으로 줄일 수 있는 '국가 지진 조기 경보 체계'를 2020년까지 구축하고자 하는 기본 계획을 수립하였으며, 본 계획의 일환으로 메시지 전달매체 중의 하나로 고려되고 있는 개인용, 이동형인 방송매체인 T-DMB 방송망과의 연계에 대한 연구가 진행되고 있다. 이에 본 논문은 지진 조기 경보 시스템과 지상파 DMB 방송망을 연계하여, 지진 재해와 같은 재난발생시 기존의 단순 속보형태로의 전달이 아니라, 수신기가 자동으로 재난방송 신호를 인지하여 사용자의 시청 유무와 상관없이 지진조기경보 정보를 제공할 수 있는 지진재해 자동인지 조기경보 서비스 기술 및 송수신 시스템을 소개한다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.6
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• pp.851-858
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• 2012

In this paper, we design a seismic data acquisition system(SDAS) and implement it. This system is essential for development of a noble local earthquake disaster preventing system in population center. In the system, we choose a proper MEMS-type triaxial accelerometer as a sensor, and FPGA and ARM processor are used for implementing the system. In the SDAS, each module is realized by Verilog HDL and C Language. We carry out the ModelSim simulation to verify the performances of important modules. The simulation results show that the FPGA-based data acquisition module can guarantee an accurate time-synchronization for the measured data from each axis sensor. Moreover, the FPGA-ARM based embedded technology in system hardware design can reduce the system cost by the integration of data logger, communication sever, and facility control system. To evaluate the data acquisition performance of the SDAS, we perform experiments for real seismic signals with the exciter. Performances comparison between the acquired data of the SDAS and the reference sensor shows that the data acquisition performance of the SDAS is valid.

• Journal of the Korea Society of Computer and Information
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• v.12 no.5
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• pp.29-37
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• 2007

In this paper, we propose a new real-time ground motion monitoring system using MMA data which can be gathered more earlier than generic seismic data transmission method. Proposed system receives maximum, minimum and average data based on 20sps which is sent from station on every second continuously. And it calculates a PGA as a quantity of ground motion then visualizes that data to monitor the ground motion around whole country. To verify PGA data from MMA data, we checked Mu-dan-jang earthquake data of China on 2002/6/29. The proposed system was inspected by using log file of Oh-dae-san earthquake data on 2007/1/20. As results of experiment, the proposed system is proven to detect the event(earthquake) faster then existing method and to produce a useful quantitative information.

• Journal of the Korean Geotechnical Society
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• v.35 no.11
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• pp.121-129
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• 2019

An Earthquake Early Warning (EEW) system is a technology that alerts people to an incoming earthquake by using P waves that are detected before the arrival of more severe seismic waves. P-wave analysis is therefore an important factor in the production of rapid seismic information as it can be used to quickly estimate the earthquake magnitude and epicenter through the amplitude and predominant period of the observed P-wave. However, when a large-magnitude teleseismic earthquake is observed in a local seismic network, the significantly attenuated P wave phases may be mischaracterized as belonging to a small-magnitude local earthquake in the initial analysis stage. Such a misanalysis may be sent to the public as a false alert, reducing the credibility of the EEW system and potentially causing economic losses for infrastructure and industrial facilities. Therefore, it is necessary to develop methods that reduce misanalysis. In this study, the possibility of seismic misclassifying teleseimic earthquakes as local events was reviewed using the Filter Bank method, which uses the attenuation characteristics of P waves to classify local and outside Korean peninsula (regional and teleseismic) events with filtered waveform depending on frequency and epicenter distance. The data used in our analysis were analyzed for maximum P_v values using 463 events with local magnitudes (2 < M_L ≦ 3), 44 (3 < M_L ≦ 4), 4 (4 < M_L ≦ 5), 3 (M_L > 5), and 89 outside Korean peninsula earthquakes recorded by the KMA seismic network. The results show that local and telesesimic earthquakes can be classified more accurately when combination of filtering bands of No. 3 (6-12 Hz) and No. 6 (0.75-1.5 Hz) is applied.