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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.
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
103.
104.
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
105.
106.
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
107.
108.
109.
Consistency of seven different GNSS global ionospheric mapping techniques during one solar cycle 总被引:1,自引:0,他引:1
David Roma-Dollase Manuel Hernández-Pajares Andrzej Krankowski Kacper Kotulak Reza Ghoddousi-Fard Yunbin Yuan Zishen Li Hongping Zhang Chuang Shi Cheng Wang Joachim Feltens Panagiotis Vergados Attila Komjathy Stefan Schaer Alberto García-Rigo José M. Gómez-Cama 《Journal of Geodesy》2018,92(6):691-706
In the context of the International GNSS Service (IGS), several IGS Ionosphere Associated Analysis Centers have developed different techniques to provide global ionospheric maps (GIMs) of vertical total electron content (VTEC) since 1998. In this paper we present a comparison of the performances of all the GIMs created in the frame of IGS. Indeed we compare the classical ones (for the ionospheric analysis centers CODE, ESA/ESOC, JPL and UPC) with the new ones (NRCAN, CAS, WHU). To assess the quality of them in fair and completely independent ways, two assessment methods are used: a direct comparison to altimeter data (VTEC-altimeter) and to the difference of slant total electron content (STEC) observed in independent ground reference stations (dSTEC-GPS). The main conclusion of this study, performed during one solar cycle, is the consistency of the results between so many different GIM techniques and implementations. 相似文献
110.
Planning the Colca Canyon and the Valley of the Volcanoes National Park in South Peru 总被引:1,自引:1,他引:0
The economic development of the Rio Colca region and related infrastructure endangers the environment of the deepest canyon worldwide. The unique values of the Colca Valley and Canyon and its tributary Valley of the Volcanoes are summarised. They include a magnificent, deep section of the orogenic belt 100 km long, different geological formations, active faults, a variety of fold structures, young volcanoes, hot springs, geysers, several ecological zones and the largest condor habitat in the Andes. Based on the observed land use, development and regional planning, the threats and conflict areas are outlined. Studies performed by the Polish Scientific Expedition to Peru since 2003 add greatly to the knowledge of geology, landscape and pioneering biota development of the area and its importance to the world heritage of nature. They are aimed to give scientific background to the project of the Canyon Colca and Valley of the Volcanoes National Park. The article gives the proposed limits of the park and its buffer zones, categories of protection zones compatible with the SINANPE system of Peru and suggestions on tourist accessibility. The strict protection zone should cover the most inaccessible part of the area where human economic activity practically does not exist. Traditional farming and animal husbandry, wildlife, cultural tourism and some forms of adventure tourism will be allowed in the zone of special usage. The new park would strengthen the relatively poor system of the protected areas in the Arequipa Department, increase tourist attractiveness and determine constraints for sustained regional development. The expected actions of the park authority and local governments are specified. 相似文献