• 제목/요약/키워드: tsunami

검색결과 395건 처리시간 0.025초

쓰나미 파형이 수중식생의 에너지소산에 미치는 영향 (Effects of Tsunami Waveform on Energy Dissipation of Aquatic Vegetation)

  • 이우동;박종률;전호성;허동수
    • 한국해양공학회지
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    • 제31권2호
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    • pp.121-129
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    • 2017
  • The present study numerically investigated the influence of the waveform distribution on the tsunami-vegetation interaction using a non-reflected wave generation system for various tsunami waveforms in a two-dimensional numerical wave tank. First, it was possible to determine the wave attenuation mechanism due to the tsunami-vegetation interaction from the spatial waveform, flow field, vorticity field, and wave height distribution. The combination of fluid resistance in the vegetation and a large gap and creates a vortex according to the flow velocity difference in and out of the vegetation zone. Thus, the energy of a tsunami was increasingly reduced, resulting in a gradual reduction in wave height. Compared to existing approximation theories, the double volumetric ratio of the waveform increased the reflection coefficient of the tsunami-vegetation interaction by 34%, while decreasing the transfer coefficient and energy attenuation coefficient by 25% and 13%, respectively. Therefore, the hydraulic characteristics of a tsunami is highly likely to be underestimated if the solitary wave of the approximation theory is applied for the tsunami.

Tsunami (津波)의 한글표현에 대한 소고 (A study on terminological definition of tsunami in Korean)

  • 정태화;손상영
    • 한국수자원학회논문집
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    • 제56권5호
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    • pp.363-371
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    • 2023
  • 본 연구에서는 tsunamii(津波)의 한글표현인 지진해일의 과학적 타당성에 대해 고찰하고 올바르게 활용할 수 있는 방안을 제안하고자 한다. 우선 tsunami의 과학적 정의를 짚어보고 다양한 언어로 표현된 tsunami의 유래를 살펴본다. 이를 바탕으로 현재 우리나라에서 대표적으로 사용되는 tsunami의 한글표현 '지진해일'이 목적에 적합하게 활용되고 있는지에 대해 검토한 후, 타당하게 활용될 수 있는 방안을 제시한다. 결론적으로 본 연구에서는 tsunami의 한글표현에 있어서 영어 및 타 언어들의 경우와 마찬가지로 음을 차용하여 표현한 '쓰나미' 혹은 '쯔나미'로 통일성 있게 사용할 것을 제안한다.

OBSERVATIONS BY SATELLITE ALTIMETRY OF SHORT SURFACE WAVE ENERGY IN THE DECEMBER 2004 SUMATRA TSUNAMI

  • Gower, Jim
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.43-46
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    • 2006
  • The main tsunami wave triggered by the December 2004 Sumatra tsunami was detected in the ocean south of India by satellite altimeters on Jason, Topex/Poseidon and Envisat. All three altimeters also detected shorter-wavelength (10 to 100 km), slower-propagating surface waves, spreading from the site of the earthquake. The shorter waves give additional information about the tsunami event, and can be used to better define the generating region in this, and future tsunamis. The properties of the area of shorter tsunami-generated waves may also be important in designing a future satellite-based detection system.

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지진해일의 피해와 예보체계 (Damage Caused by Tsunami and Warning System)

  • 강영승
    • 기술사
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    • 제38권1호
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    • pp.59-63
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    • 2005
  • A Tsunami was generated by the magnitude 9.0 earthquake which occurred near Indonesia. An energetic Tsunami will display vertical water displacement of the order of ten meters and lateral scales of the order of tens of kilometers. The Tsunami destroyed many coastal villages in Asia. So, there are many victims in southeastern part Asia by Tsunami. Therefore, the construction of Tsunami prediction and warning system is needed for minimize the damage by seismic sea waves.

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임원항의 지형특성을 고려한 지진해일 피난 수치모형 연구 (Study on evacuation simulation for tsunami using the characteristics of Imwon Port)

  • 김성민;심주열;조용식
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2008년도 정기총회 및 학술발표대회
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    • pp.221-223
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    • 2008
  • It is the best way that to make an inundation map and distribute it to inhabitants for the purpose of decreasing damage of tsunami. To make an inundation map, tsunami which broughthuge damage to Korea should be properly investigated and maximum inundation zonewas selected by simulating tsunami phenomenan. An inundation map must involve the location of shelters and evacuation routes. New evacuation simulation program connected evacuation simulation procedure and tsunami inundation procedure to get inhabitants' evacuation states in real-time.

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직립호안에서 지진해일 파형이 월파와 침수에 미치는 영향 (Effects of tsunami waveform on overtopping and inundation on a vertical seawall)

  • 이우동;김정욱;박종률;허동수
    • 한국수자원학회논문집
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    • 제51권8호
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    • pp.643-654
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    • 2018
  • 수치파동수조에서 안정적인 지진해일을 조파하기 위하여 2차원 수치모델(LES-WASS-2D)에 다양한 파형의 지진해일을 고려할 수 있는 무반사 조파시스템을 도입하였다. 기존 실험에서 측정한 호안주변의 지진해일의 시 공간 파형들과 비교하여 수치계산결과가 높은 정확도를 나타내었다. 이로써 본 연구에서 적용한 수치모델이 지진해일 월파모의에 있어서 적합하다는 것을 보여주었다. 지진해일 월파모의결과로부터 지진해일 체적비와 파고와 수심비에 따른 월퍄량, 침수거리를 고찰하였다. 지진해일의 파형이 넓을수록 월파량이 선형적으로 증가하였으며, 침수거리 또한 증가하였다. 그러므로 고립파 근사이론을 지진해일의 월파 및 침수모의에 적용할 경우, 실제 지진해일보다 수리특성이 과소평가 될 우려가 크다.

일본 서부 단층 지진원을 고려한 확률론적 지진해일 재해도 분석의 파고 변수 도출 (Estimation of Wave Parameters for Probabilistic Tsunami Hazard Analysis Considering the Fault Sources in the Western Part of Japan)

  • 이현미;김민규;신동훈;최인길
    • 한국지진공학회논문집
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    • 제18권3호
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    • pp.151-160
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    • 2014
  • Probabilistic tsunami hazard analysis (PTHA) is based on the approach of probabilistic seismic hazard analysis (PSHA) which is performed using various seismotectonic models and ground-motion prediction equations. The major difference between PTHA and PSHA is that PTHA requires the wave parameters of tsunami. The wave parameters can be estimated from tsunami propagation analysis. Therefore, a tsunami simulation analysis was conducted for the purpose of evaluating the wave parameters required for the PTHA of Uljin nuclear power plant (NPP) site. The tsunamigenic fault sources in the western part of Japan were chosen for the analysis. The wave heights for 80 rupture scenarios were numerically simulated. The synthetic tsunami waveforms were obtained around the Uljin NPP site. The results show that the wave heights are closely related with the location of the fault sources and the associated potential earthquake magnitudes. These wave parameters can be used as input data for the future PTHA study of the Uljin NPP site.

Transoceanic Propagation of 2011 East Japan Earthquake Tsunami

  • Choi, Byung Ho;Kim, Kyeong Ok;Min, Byung Il;Pelinovsky, Efim
    • Ocean and Polar Research
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    • 제36권3호
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    • pp.225-234
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    • 2014
  • The 2011 Tohoku earthquake triggered extremely destructive tsunami waves which propagated over the Pacific Ocean, Atlantic Ocean through Drake Passage and Indian Ocean respectively. A total of 10 tide-gauge records collected from the UNESCO/IOC site were analyzed through a band-pass digital filtering device to examine the observed tsunami characteristics. The ray tracing method and finite-difference model with GEBCO 30 arc second bathymetry were also applied to compare the travel times of the Tohoku-originated tsunami, particularly at Rodrigues in the Indian Ocean and King Edward Point in the Atlantic Ocean with observation-based estimates. At both locations the finite-difference model produced the shortest arrival times, while the ray method produced the longest arrival times. Values of the travel time difference however appear to be within tolerable ranges, considering the propagation distance of the tsunami waves. The observed tsunami at Rodrigues, Mauritius in the west of the Madagascar was found to take a clockwise travel path around Australia and New Zealand, while the observed tsunami at King Edward Point in the southern Atlantic Ocean was found to traverse the Pacific Ocean and then passed into the Atlantic Ocean through the Drake Strait. The formation of icebergs captured by satellite images in Sulzberger in the Antarctica also supports the long-range propagation of the Tohoku-originated tsunami.

THE ROLE OF SATELLITE REMOTE SENSING TO DETECT AND ASSESS THE DAMAGE OF TSUNAMI DISASTER

  • Siripong, Absornsuda
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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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.

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지진 및 해일 대비 안전교육에 대한 보육교사들의 인식 및 실태조사 연구 (Early childhood teachers' perspectives and actual conditions of earthquakes and tsunami safety education)

  • 양선이
    • 한국응급구조학회지
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    • 제15권3호
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    • pp.81-96
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    • 2011
  • Purpose : The purpose of this study was to analyse early childhood teachers' perspectives and actual conditions of earthquakes and tsunami safety education. Methods : A total of 119 teachers were recruited from kindergarten and child-care center located in J city, all of whom gave consent to take part in these research. The data have been collected for 45 days from May to July in 2011. The data was analyzed by SPSS (version 17.0) and chi-square test. Results : The results of this study are summarized as follow. 1. 97.5% of the subjects considered earthquakes and tsunami safety education necessary, however, only 34.6% of them were given the education related to earthquakes and tsunami. 2. 63.9% of the early childhood teachers provided children in the kindergarten or childhood center with earthquakes and tsunami safety education, however, 30.3% of them were found to be without any experiences of earthquakes and tsunami safety education. 3. 68.5% of the teachers were informed earthquakes and tsunami safety knowledge. 4. 35.0% of respondents answered that the single session of earthquake and tsunami education was not efficient, thus expecting to receive continuing education. Conclusions : The study suggested that more teachers necessarily provide earthquake and tsunami safety education to reduce children's mortality rate in earthquakes and tsunami. The education program should be developed and systematized to improve teacher's knowledge. Moreover, the program should be continuously provided to teachers and children in the kindergarten or childhood center.