A multiscale modeling of damage and time‐dependent behavior of cohesive rocks     

A. Abou‐Chakra Guéry  F. Cormery  J. F. Shao  D. Kondo 《国际地质力学数值与分析法杂志》2009,33(5):567-589

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Potential of low cost close‐range photogrammetry system in soil microtopography quantification     

Mohamed A. M. Abd Elbasit  Hisao Anyoji  Hiroshi Yasuda  Shunichi Yamamoto 《水文研究》2009,23(10):1408-1417

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A simple parameterization of longwave radiative cooling with application to the atmospheric boundary layer for clear sky conditions     

Junsei Kondo  Dai Matsushima 《Boundary-Layer Meteorology》1993,64(3):209-229

A simple parameterization is proposed to obtain longwave radiative cooling rates, which can be used for atmospheric boundary-layer simulations on clear days in mid-latitudes. The net flux difference which is set to zero at the surface, can be parameterized with the use of three variables: the surface temperature, the lowest level (1.5 m) air temperature, and the total amount of water vapor. If these three elements, along with the water vapor profile are known, it is possible to estimate the cooling rate due to longwave radiation. The results of this parameterization are in good agreement with those of a precise scheme (Roach and Slingo, 1979), within a range of ± 1°C/day of diurnal change for boundary-layer simulations.  相似文献   

Synchrotron radiation study on the high-pressure and high-temperature phase relations of KAlSi3O8     

S. Urakawa  T. Kondo  N. Igawa  O. Shimomura  H. Ohno 《Physics and Chemistry of Minerals》1994,21(6):387-391

In situ X-ray diffraction study on KAlSi₃O₈ has been performed using the cubic type high pressure apparatus, MAX90, combined with synchrotron radiation. We determined the phase relations of sanidine, the wadeite-type K₂Si₄O₉+kyanite (Al₂SiO₅)+coesite (SiO₂) assemblage, and hollandite-type KAlSi₃O₈, including melting temperatures of potassic phases, up to 11 GPa. Our data on subsolidus phase boundaries are close to the recent data of Yagi and Akaogi (1991). Melting relations of sanidine are consistent with the low pressure data of Lindsley (1966). The breakdown of sanidine into three phases reduces melting temperature, and wadeite-type K₂Si₄O₉ melts first around 1500° C in three phase coexisting region. Melting point of hollandite-type KAlSi₃O₈ is between 1700° C and 1800° C at 11 GPa. If these potassic phases host potassium in the earth's mantle, the true mantle solidus temperature will be much lower than the reported dry solidus temperature of peridotite.  相似文献   

Equation of state of iron–silicon alloys to megabar pressure     

N.?HiraoEmail author  E.?Ohtani  T.?Kondo  T.?Kikegawa 《Physics and Chemistry of Minerals》2004,31(6):329-336

The stability and pressure–volume equation of state of iron–silicon alloys, Fe-8.7 wt% Si and Fe-17.8 wt% Si, have been investigated using diamond-anvil cell techniques up to 196 and 124 GPa, respectively. Angular–dispersive X-ray diffractions of iron–silicon alloys were measured at room temperature using monochromatic synchrotron radiation and an imaging plate (IP). A bcc–Fe-8.7 wt% Si transformed to hcp structure at around 1636 GPa. The high-pressure phase of Fe-8.7 wt% Si with hexagonal close-packed (hcp) structure was found to be stable up to 196 GPa and no phase transition of bcc–Fe-17.8 wt% Si was observed up to 124 GPa. The pressure–volume data were fitted to a third-order Birch–Murnaghan equation of state (BM EOS) with zero–pressure parameters: V₀=22.2(8) ų, K₀=198(9) GPa, and K₀=4.7(3) for hcp–Fe-8.7 wt% Si and V₀=179.41(45) ų, K₀=207(15) GPa and K₀=5.1(6) for Fe-17.8 wt% Si. The density and bulk sound velocity of hcp–Fe-8.7 wt% Si indicate that the inner core could contain 3–5 wt% Si.  相似文献   

Discontinuity of the Mozumi–Sukenobu fault low-velocity zone, central Japan, inferred from 3-D finite-difference simulation of fault zone waves excited by explosive sources     

Yutaka Mamada  Yasuto Kuwahara  Hisao Ito  Hiroshi Takenaka 《Tectonophysics》2004,378(3-4):209

We delineate shallow structures of the Mozumi–Sukenobu fault, central Japan, using fault zone waves generated by near-surface explosions and detected by a seismometer array. Two explosive sources, S1 and S2, were placed at a distance of about 2 km from the array, and the other two, S3 and S4, were at a distance of about 4 km. Fault zone head waves and fault zone trapped waves following direct P wave arrivals were clearly identified in the seismograms recorded by a linear seismometer array deployed across the fault in a research tunnel at a depth of 300 m. Synthetic waveforms generated by a 3-D finite-difference (3-D FD) method were compared with observed fault zone waves up to 25 Hz. The best fitting model indicates a 200-m-wide low-velocity zone extending at least to shot site S1 located 2 km east of the seismic array with a 20% decrease in the P wave velocity relative to the wall rock. The width of the low-velocity zone is consistent with the fault zone defined by direct geological observation in the research tunnel. However, the low-velocity zone should disappear just to the east of the site S1 to explain the observed fault zone waves for shot S3 and S4 located 4 km east of the seismometer array. Yet the observation and the simulation show notable trapped wave excitation even though shots S3 and S4 are outside the fault zone. These results indicate that (1) the effective waveguide for seismic waves along the fault does not exist east of source site S1 although the surface traces of the fault are observed in this region, and (2) considerable trapped waves can be excited by sources well outside the fault zone. These results highlight the along-strike variability in fault zone structure.  相似文献   

Deep structure of the Mozumi-Sukenobu fault, central Japan, estimated from the subsurface array observation of fault zone trapped waves   总被引：1，自引：0，他引：1  

Takashi Mizuno  Kin'ya Nishigami  Hisao Ito  Yasuto Kuwahara 《Geophysical Journal International》2004,159(2):622-642

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Inland penetration of the sea breeze over the suburban area of Tokyo     

Hiroshi Yoshikado  Hiroaki Kondo 《Boundary-Layer Meteorology》1989,48(4):389-407

Observational results of the structure of the sea breeze over the urban and suburban areas of Tokyo for four summer days are presented.On two of these days, the inland penetration of the sea breeze front could be clearly traced. In one case, the sea breeze was first observed along the shores of Tokyo Bay around 0900 JST, and propagated in three hours through the Tokyo City area, the width of which is about 20 km. It then advanced inland at a rate of 16 km h^–1. Prior to the arrival of the sea breeze at the suburban site, the mixing height had remained at about 600 m for four hours. With the arrival of the sea breeze front, accompanied by an abrupt change in wind speed and direction, the mixing height increased sharply to 1700 m. It is suggested that this behavior and the structure of the front are intensified due to the urban effect, or the difference in the thermal characteristics between the urban and rural areas.On the days without a sea breeze front, the land breeze system during the early morning was less intense, allowing the sea breeze to develop simultaneously with the inland valley wind and easily form a large-scale local wind system during the morning hours. In both cases, the vertical motion accompanying the local wind system works as a feedback mechanism to control the local winds by modifying the thermal and pressure fields.  相似文献   

Aircraft measurements of oxides of nitrogen along the eastern rim of the Asian continent: Winter observations     

Y. Kondo  W. A. Matthews  A. Iwata  Y. Morita  M. Takagi 《Journal of Atmospheric Chemistry》1987,5(1):37-58

Aircraft observations of oxides of nitrogen (NO _y ), measured with a ferrous sulfate converter, over the sea surrounding the Japanese islands (30–43° N, 131–141° E) were carried out in the winter of 1983 and 1984 at altitudes mostly between 3 and 8 km. NO _y defined here is the sum of NO, NO₂, and other unstable oxides of nitrogen that are converted to NO by ferrous sulfate. The main observations were:

1. Over the Pacific Ocean between the latitudes of 30–35° N, the observed NO _y mixing ratio between 3 and 8 km was a fairly constant 200 pptv. The NO mixing ratio increased with altitude from 15 pptv at 3 km to 35 pptv at 7 km.
2. Over the Sea of Japan, tropospheric NO _y mesured between 1 and 6 km started increasing with latitude North of 35° N and reached about 1000 pptv at 40° N.
3. NO _y was measured in an air mass transported from the stratosphere near a tropopause fold region. When the ozone mixing ratio was between 80 and 140 ppbv, the NO _y mixing ratio was about 200 pptv.

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The selectivity of the Ioannina VAN station     

S. Kondo  S. Uyeda  T. Nagao   《Journal of Geodynamics》2002,33(4-5)

Two peculiar characteristics of the VAN method of short-term earthquake prediction are: (1) the existence of sensitive and insensitive sites to seismic electric signal (SES) and (2) the selective sensitivity of a sensitive station to SES from specific focal area(s). The process of their discovery, which so far has not been published adequately, is examined for the Ioannina (IOA) station. The sensitive site was discovered simply through repeatedly moving the temporary observation network. The selectivity map of the IOA station was made by first identifying the earthquake source areas with SESs which were considered to have been detected at IOA, and second by examining the direction of SESs from different such source areas. For the latter purpose, information from long dipoles appears to have been helpful. The selectivity map is empirically constructed and is updated regularly. We have independently tried to construct a selectivity map of IOA by examining VAN's raw SES records and by using the same criteria as VAN. The selectivity map we obtained was not exactly, but roughly similar to that of VAN.  相似文献