Changes in population evacuation potential for tsunami hazards in Seward, Alaska, since the 1964 Good Friday earthquake   总被引：1，自引：0，他引：1  

Nathan J. Wood  Mathew C. Schmidtlein  Jeff Peters 《Natural Hazards》2014,70(2):1031-1053

Pedestrian evacuation modeling for tsunami hazards typically focuses on current land-cover conditions and population distributions. To examine how post-disaster redevelopment may influence the evacuation potential of at-risk populations to future threats, we modeled pedestrian travel times to safety in Seward, Alaska, based on conditions before the 1964 Good Friday earthquake and tsunami disaster and on modern conditions. Anisotropic, path distance modeling is conducted to estimate travel times to safety during the 1964 event and in modern Seward, and results are merged with various population data, including the location and number of residents, employees, public venues, and dependent care facilities. Results suggest that modeled travel time estimates conform well to the fatality patterns of the 1964 event and that evacuation travel times have increased in modern Seward due to the relocation and expansion of port and harbor facilities after the disaster. The majority of individuals threatened by tsunamis today in Seward are employee, customer, and tourist populations, rather than residents in their homes. Modern evacuation travel times to safety for the majority of the region are less than wave arrival times for future tectonic tsunamis but greater than arrival times for landslide-related tsunamis. Evacuation travel times will likely be higher in the winter time, when the presence of snow may constrain evacuations to roads.  相似文献   

Measured and Back Analysed Soil Structure Interaction Effects in a Layered Stratigraphy During Tunnel Boring     

Gima V. Mathew  Barry M. Lehane 《Geotechnical and Geological Engineering》2014,32(4):873-884

The paper compares the soil structure interaction effects predicted using a finite element (FE) program with those observed during a bored tunnel project conducted in Perth, Western Australia. Both the measured data and geotechnical characteristics of the subsoils are described before presenting comparisons between measurements and analyses. The measured settlement data for two buildings are seen to be dependent on the structural stiffness. It is shown that, in keeping with observations by others, FE predictions of tunnelling induced movement patterns are not predicted to a satisfactory level of accuracy. However, it is also shown that FE analyses of the type described may be employed to provide qualitative information on soil-structure interaction effects.  相似文献   

A Digital Imaging Multi-Slit Spectrograph for Measurement of Line-of-Sight Velocities on the sun     

Nandita Srivastava  Shibu K. Mathew 《Solar physics》1999,185(1):61-68

A multi-slit digital imaging spectrograph has been installed at Udaipur Solar Observatory, Udaipur (India) to measure the line-of-sight velocities in H associated with the mass motions of the dynamic phenomena on the solar surface viz. solar flares, eruptive prominences and surges. This spectrograph is being used in conjunction with a 15 cm aperture Coudé telescope to obtain the H spectra at a high rate of a specific region of interest on the Sun. In this paper, we describe the principal features of this instrument and the data acquisition method. We also present spectral observations of a surge and a quiescent prominence recorded using this instrument.  相似文献   

The Torino,H6, meteorite shower     

N. Bhandari  G. Bonino  E. Callegari  G. Cini Castagnoli  K. J. Mathew  J. T. Padia  G. Queirazza 《Meteoritics & planetary science》1989,24(1):29-34

Abstract— A meteorite shower fell at Torino, Italy on 18 May 1988. Petrographic studies indicate that the stone is an H6 chondrite having features of moderate to severe shock. Chemical analyses of the meteorite are reported. Cosmic ray produced ³He, ²¹Ne and ¹²⁶Xe yield an exposure age of about 48 Ma. The cosmic ray track densities in three fragments range between 1.8 to 5 × 10⁵/cm² suggesting about 99% mass ablation in the atmosphere. Twelve radioisotopes with half lives ranging between 5.6 days to 7.3 × 10⁵ years have been measured with high precision (2 to 10%). Marginal signals were observed for several short-lived nuclides and upper limits were obtained for the activity levels of eight radionuclides (²⁴Na, ⁴⁸Cr, ⁵⁷Ni, ⁴⁷Sc, ⁴⁷Ca, ⁵⁹Fe, ⁴²Ar and ⁴⁴Ti) some of which have not been hitherto detected in fresh falls. The data are generally consistent with the nuclide production by galactic cosmic rays when modulation due to the solar cycle is taken into consideration. The preatmospheric radius of the chondrite is estimated to be 20 cm, consistent with track densities and activity levels of ⁶⁰Co, ²⁶Al and other radionuclides.  相似文献   

Effects of rotation on the colours and line indices of stars     

Annamma Mathew  R. Rajamohan 《Journal of Astrophysics and Astronomy》1990,11(2):167-191

The intrinsicuvby and HΒ indices of member stars of α-Persei, Pleiades and Scorpio-Centaurus association have been analysed in detail for rotation effects. These stars range in spectral type from B0 to F0 and the observed effects of rotation are found to be in agreement with photometric effects calculated by Collins & Sonneborn (1977) for rigidly rotating B0 to F0 stars On leave of absence from Assumption College, Changanacherry, Kerala.  相似文献   

A model of tidal flushing of an estuary by dipole formation     

Mathew G. Wells  Gert-Jan F. van Heijst 《Dynamics of Atmospheres and Oceans》2003,37(3):223-244

We discuss a laboratory model of the flushing and mixing between a bay and a sea connected by a narrow channel. Tidal changes in water elevation lead to periodic flow in and out of the bay through the narrow channel. Due to flow separation there is an asymmetry between the flow entering and leaving the channel on different phases of the tide. A consequence of this asymmetry is that every tidal cycle a fraction of fluid is not returned through the channel, so that a passive tracer in the bay is successively flushed away. We consider what happens when the creation of vorticity in the channel leads to the formation of a dipole that can propagate away from the returning flow of the later phase of the tide. When the dimensionless ratio of maximum channel velocity U, width of channel W and tidal period T is such that W/UT<0.13, we find that dipoles can propagate away from the source region without being drawn back into the sink. This process leads to a larger exchange of water between the estuary and sea, than the classical model of tidal flushing by the jet-sink asymmetry of [Stommel, H., Farmer, H. G., 1952. On the nature of estuarine circulation WHOI Tech. Rep. 52–88, 131].  相似文献   

Hydrography and circulation off the Antarctica in the Indian Ocean region     

G S Sharma  Basil Mathew 《Journal of Earth System Science》1985,94(1):13-27

The hydrography and circulation pattern off Antarctica in the Indian Ocean region are studied using vertical sections of temperature, salinity and oxyty approximately along 20°E, 77°E and 90°E, and the dynamic topography of the sea surface with reference to 1000 db. Based on the oceanographic characteristics, the whole region under study can be divided into three zones, the extreme ends being characterised by the frontal structure. The dicothermal layer is conspicuous during summer south of 50°S. The surface flow around Antarctica is mainly zonal. The East Wind Drift, found as a narrow westward flow near Antarctica, is observed at a lower latitude in the eastern Indian Ocean where the land extends northword. Contrary to expectation there is evidence of a westward flowing surface current at about 35°S between 45°E and 65°E.  相似文献   

Insolation over the Arabian Sea during the southwest monsoon     

P. V. Hareesh Kumar  N. Mohan Kumar  Basil Mathew 《Boundary-Layer Meteorology》1991,56(1-2):197-203

The relationship between monsoon cloud cover and incoming solar radiation in the Arabian Sea is examined utilising the available observations of daily mean total cloud amount and solar radiation collected during the summer monsoon. With these data sets, various cloud correction formulae are evaluated. For the estimation of solar radiation, the formulation of Laevastu (1960) is best, with a minimum error of -4%. A multiple polynomial regression equation based on cloud cover and noon altitude of the sun is developed for estimation of daily radiation. The error between estimated and observed radiation is -2%.  相似文献   

India at crossroads for energy     

Mu Ramkumar  M.Santosh  Manoj J.Mathew  Numair A.Siddiqui 《地学前缘(英文版)》2021,12(6):356-360

As one of the fastest growing economies and further larger consumer of energy in the world,there has been a paradigm shift in India's energy demand.Here we evaluate the growth of Indian economy its,diversification of agriculture-based economy to industrial production,service and digital-technology based economy and deepening of income sources,although the dependence on foreign sources for energy demands has not markedly improved.This situation has placed India at the crossroads for energy sufficiency,especially under the highly fluid and changing geopolitical,strategic,environmental and economic scenarios of the World order.We attempt to un-derstand the issue from geological perspective and address some of the impediments.  相似文献   

Constraints on surface deformation in the Seattle, WA, urban corridor from satellite radar interferometry time-series analysis     

Noah J. Finnegan  Mathew E. Pritchard  Rowena B. Lohman  Paul R. Lundgren 《Geophysical Journal International》2008,174(1):29-41

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