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101.
Andrzej J. Maciejewski Maria Przybylska 《Celestial Mechanics and Dynamical Astronomy》2004,89(2):145-164
We consider two fixed centres attracting a third body. Each centre is the source of a force field with potential V=−ar
−2n
, where n is a real number. We prove that this generalization of the classical two fixed centres problem is non-integrable except when
n= 0, 1/2, −1 and −2.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
102.
Strain accumulation in sand due to cyclic loading: Drained cyclic tests with triaxial extension 总被引:1,自引:0,他引:1
T. Wichtmann A. Niemunis Th. Triantafyllidis 《Soil Dynamics and Earthquake Engineering》2007,27(1):42-48
This paper presents results of numerous drained cyclic tests with triaxial extension. The influence of the strain amplitude, the average stress and the number of load cycles on the accumulation rate was studied. A simple cyclic flow rule was observed. Most findings confirm a previous study with cyclic triaxial compression tests. The test results serve as the basis of an explicit accumulation model. 相似文献
103.
Kaja Pietsch Paweł Marzec Marcin Kobylarski Tomasz Danek Andrzej Leśniak Artur Tatarata Edward Gruszczyk 《Acta Geophysica》2007,55(2):191-208
The thin-layer build of the Carpathian Foredeep Miocene formations and large petrophysical parameter variation cause seismic
images of gas-saturated zones to be ambiguous, and the location of prospection wells on the basis of anomalous seismic record
is risky. A method that assists reservoir interpretation of standard recorded seismic profiles (P waves) can be a converted wave recording (PS waves).
This paper presents the results of application of a multicomponent seismic survey for the reservoir interpretation over the
Chałupki Dębniańskie gas deposit, carried out for the first time in Poland by Geofizyka Kraków Ltd. for the Polish Oil and
Gas Company. Seismic modeling was applied as the basic research tool, using the SeisMod program based on the finite-difference
solution of the acoustic wave equation and equations of motion. Seismogeological models for P waves were developed using Acoustic Logs; S-wave model (records only from part of the well) was developed on the basis of theoretical curves calculated by means of the
Estymacja program calibrated with average S-velocities, calculated by correlation of recorded P and PS wavefields with 1D modeling.
The conformity between theoretical and recorded wavefields makes it possible to apply the criteria established on the basis
of modeling for reservoir interpretation. Direct hydrocarbon indicators (bright spots, phase change, time sag) unambiguously
identify gas-prone layers within the ChD-2 prospect. A partial range of the indicators observed in the SW part of the studied
profile (bright spot that covers a single, anticlinally bent seismic horizon) points to saturation of the horizon. The proposed
location is confirmed by criteria determined for converted waves (continuous seismic horizons with constant, high amplitude)
despite poorer agreement between theoretical and recorded wavefields. 相似文献
104.
105.
Several procedures for the statistical estimation of the region-characteristic maximum possible earthquake magnitude, m
max, are currently available. This paper aims to introduce and compare the 12 existing procedures. For each of the procedures
given, there are notes on its origin, assumptions made in its derivation, condition for validity, weak and strong points,
etc. The applicability of each particular procedure is determined by the assumptions of the model and/or the available information
on seismicity of the area. 相似文献
106.
Paraelasticity (PE) is a hysteretic, fully reversible model with rate-independent damping and with variable secant stiffness.
PE has been proposed in the companion paper (Niemunis et al. in Acta Geotech, 2011) for the 3D case. Here, paraelasticity
is extended for demanding application in geomechanics by implementation of a reversible dilatancy–contractancy. Moreover,
an implicit FE implementation for Abaqus and calculation of a boundary value problem are presented. 相似文献
107.
108.
Andrzej Woszczyna 《Astrophysics and Space Science》1983,90(1):75-78
The evolution of some vacuum spatially-flat Robertson-Walker universes filled with a massless conformally-invariant quantum field is presented in the energy density-curvature phase plane. 相似文献
109.
110.