Tsunami vulnerability evaluation in the Mentawai islands based on the field survey of the 2010 tsunami     

Takahito Mikami  Tomoya Shibayama  Miguel Esteban  Koichiro Ohira  Jun Sasaki  Takayuki Suzuki  Hendra Achiari  Teguh Widodo 《Natural Hazards》2014,71(1):851-870

On October 25, 2010, a large earthquake occurred off the coast of the Mentawai islands in Indonesia, generating a tsunami that caused damage to the coastal area of North Pagai, South Pagai, and Sipora islands. Field surveys were conducted soon after the event by several international survey teams, including the authors’. These surveys clarified the tsunami height distribution, the damage that took place, and residents’ awareness of tsunamis in the affected islands. Heights of over 5 m were recorded on the coastal area of the Indian Ocean side of North and South Pagai islands and the south part of Sipora island. In some villages, it was difficult to evacuate immediately after the earthquake because of the lack of routes to higher ground or the presence of rivers. Residents in some villages had taken part in tsunami drills or education; however, not all villages shared awareness of tsunami threats. In the present paper, based on the results of these field surveys, the vulnerability of these islands with regards to future tsunami threats was analyzed. Three important aspects of this tsunami disaster, namely the geographic disadvantage of the islands, the resilience of buildings and other infrastructure, and people’s awareness of tsunamis, are discussed in detail, and corresponding tsunami mitigation strategies are explained.  相似文献   

Records of environmental and ecological changes related to excavation in varve sediment from Lake Hiruga in central Japan     

Seto  Koji  Katsuki  Kota  Tsujimoto  Akira  Kitagawa  Junko  Yamada  Kazuyoshi  Suzuki  Yoshiaki 《Journal of Paleolimnology》2022,68(3):329-343

Journal of Paleolimnology - Sub-annual-scale environmental and ecosystem changes since the mid-18th century were reconstructed in a semi-closed lagoon, Lake Hiruga, located along the Sea of Japan...  相似文献   

Methods to correct the variable graduation error of the meridian circle     

M. Miyamoto  S. Suzuki 《Astrophysics and Space Science》1991,177(1-2):251-257

In the automated(computerized) meridian circle, the graduation error can be calibrated in a short time: a complete determination of the graduation error takes a few days, while a coarse measurement of the first ten dominant Fourier components of the graduation error takes only 15 min. Thus, we can monitor the annual and diurnal variations of the graduation. In our regular observations, the annual variation can be thus corrected for. This kind of correction seems to be necessary, judging from the observing accuracy of modern meridian observations. On the other hand, we could not detect a change of the graduation within one clear day as far as the dominant components of the diameter error are concerned. In our case we can therefore assume the graduation error to be constant within one day.  相似文献   

Physics in Next Geoneutrino Detectors     

Atsuto Suzuki 《Earth, Moon, and Planets》2006,99(1-4):359-368

The KamLAND liquid scintillator detector demonstrated the detection of antineutrinos produced by natural radioactivities in the Earth, so-called geoneutrinos. Although this first result of geoneutrinos is consistent with current geophysical models, more accurate measurements are essential to provide a new window for exploring the inside of the Earth. In this article I would like to discuss the future prospects of KamLAND geoneutrino detection, and the possibility of directional measurement of incoming geoneutrinos. It is interesting to consider the application of geoneutrino detectors to measurements of other neutrino signals. The possibility of detecting the solar 7Be, pep and CNO neutrinos is discussed. A new type detector concept is proposed not only to explore the precise measurement of reactor neutrino oscillations but also to enable us to realize the neutrino tomography inside the Earth.  相似文献   

Physical parameters identification for full-scale ten-story reinforced concrete building with degrading tri-linear model by modal iterative error correction method     

Takuya Uesaka  Kunihiko Nabeshima  Naohiro Nakamura  Takuya Suzuki 《地震工程与结构动力学》2022,51(1):153-168

To assess the post-earthquake seismic safety of buildings, it is crucial to predict seismic response, and it is necessary to set the appropriate physical parameters of the response analysis model. Numerous methods have been proposed to identify physical parameters. However, most of them are limited to linear systems, and previous researches on nonlinear systems have difficulties in practical applications. In this paper, a nonlinear response analysis model is identified for a full-scale ten-story reinforced concrete building with the degrading tri-linear stiffness model by the modal iterative error correction (MIEC) method, and the accuracy of this technique is discussed by comparing with the shaking table test.  相似文献   

Future projections of Indian Summer Monsoon under multiple RCPs using a high resolution global climate model multiforcing ensemble simulations     

Varghese  Stella Jes  Surendran  Sajani  Rajendran  Kavirajan  Kitoh  Akio 《Climate Dynamics》2020,54(3):1315-1328

Climate Dynamics - Present-day simulations (1983–2003) of a global climate model of 60-km resolution with three deep convection schemes are analysed to find the best scheme for simulation of...  相似文献   

Relation between X-ray flux and radio flux from cosmic objects     

Ikuro Suzuki 《Astrophysics and Space Science》1983,97(1):145-150

The relationship between the X-ray flux and the radio flux from cosmic objects is investigated. We consider the emission from energetic electrons on the condition in which a plasma and a magnetic field exist. As energetic electrons under the circumstances emit both X-rays by the bremsstrahlung mechanism and radio waves by the gyrosynchrotron mechanism simultaneously, it is shown that the radio flux density is closely related to the X-ray flux density. Solving an integral equation describing the X-ray flux density at Earth, we obtain the energy spectrum of electrons in the emitting region. Inserting the result into equation of the radio flux density at Earth, we obtain the direct formula between the X-ray flux density and the radio flux density. The relation is independent of the distance between Earth and cosmic sources. Assuming a power-law X-ray spectrum, we evaluate the numerical relation between two flux densities.  相似文献   

Use of colour to display the circular polarization in solar dynamic spectra     

Suzuki  S. 《Solar physics》1974,38(1):3-7

Equipment has been developed to display in colour any circular polarization in the dynamic spectra of solar radio emissions. The potential and limitations of this simple equipment are discussed on the basis of a sample record. Modifications, now under development, to improve the system are described.  相似文献   

Spectroscopic Studies of Solar Corona VII. Formation of a Coronal Loop by Evaporation     

Jagdev?SinghEmail author  Takashi?Sakurai  Kiyoshi?Ichimoto  Isao?Suzuki  Masaoki?Hagino 《Solar physics》2005,226(2):201-221

We obtained time-sequence spectroscopic observations in (Fe x) 6374 Å and (Fe xiv) 5303 Å lines successively with the 25-cm coronagraph, and narrow-band and Doppler images in 5303 Å line by the 2-D 10-cm Doppler coronagraph NOGIS at the Norikura Solar Observatory, of a coronal region for about 7 h on 9 19–20, 2001. The raster scans were obtained with a quasi-periodicity of about 14 min and NOGIS obtained the images with an interval of about 1 min. The coronal region observed showed the formation of a coronal loop by a high-speed surge in the 6374 Å line rising from one of the footpoints of the loop. Off the limb spectroscopic observations in the 6374 Å line showed large velocities along the line of sight and vertical to the solar limb at the time of formation of the loop. The 5303 Å line observations showed negligible line-of-sight velocities and low vertical velocities when compared to those in the 6374 Å line. A hump in the intensity plots in 5303 Å with height appears to move up with respect to the solar limb with an average velocity of 4km s^–1. The FWHM of the 6374 Å showed a much smaller value of about 0.7 Å near the foot point as compared to a value of 1.2 Å at larger heights at the beginning of observations. Later as the loop developed, the FWHM of 6374 Å line showed a gradual decrease along the loop up to 70 from the limb, reached a minimum value of about 0.5 Å and then increased with height during the formation of the loop; this trend lasted for about 2 h. About 3 h after the beginning of the formation of the loop, the FWHM of 6374 Å emission line showed normal values and normal rate of increase with height with some fluctuations. The FWHM of the 5303 Å line did not show such variations along the loop and showed normal decrease in FWHM with height found earlier (Singh et al., 2003a). These observations suggest that a relatively cooler plasma at a temperature of about 0.7 MK or less (corresponding to minimum value of FWHM of 0.5 Å) was ejected from the transition region with a large velocity of about 48km s^–1, heated up in the corona by some process and formed a coronal loop with a height of about 200 above the limb that had lifetime greater than 4 h. It appears that the plasma moved from one of the footpoints and the loop was formed by evaporation of chromospheric plasma. No large-scale brightening and H flare were observed in this region during the observational period of 7 h.On leave from Indian Institute of Astrophysics, Bangalore 560034, India.  相似文献   

An interpretation of the rotational temperature of the airglow hydroxyl emissions     

Katsuhisa Suzuki  Takao Tohmatsu 《Planetary and Space Science》1976,24(7):665-671

The rotational temperature of the airglow hydroxyl emissions arising from various schemes of vibrational transitions was obtained by using spectroscopic data from six observational sources. The rotational temperature was found to depend systematically on the quantum number (ν') of the upper vibrational level from which the relevant band originates. It has a doubly degrading characteristic with respect to ν' taking maximal values at ν' = 6 and 9, which exceed considerably the atmospheric temperature. It drops off quickly as ν' decreases from 9 to 7, and then from 6 to 3 after making an abrupt rise at ν' = 6. This ν'-dependence of the rotational temperature is in favor of the hypothesis that there are two routes of excitation of the hydroxyl airglow: O₃ + H = OH(ν ? 9) + O₂, and HO₂ + O = OH(ν ? 6) + O₂. The present result implies also that the relaxation time of rotation of OH in the upper mesosphere is as long as 0.1 sec; a value an order of magnitude larger than that inferred in earlier laboratory experiments.  相似文献