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941.
Fabrizio Murgia Riccardo Biddau Alessandro Concas Roberto Demontis Luca Fanfani Zeno Heilmann Cristian Lai Giuditta Lecca Eva Lorrai Marino Marrocu Vittorio Alessandro Marrone Laura Muscas Elisaveta Peneva Andrea Piras Massimo Pisu Gabriella Pusceddu Guido Satta Daniela Theis Andrea Vacca Paolo Valera Ana Melina Vallenilla Ferrara Ernesto Bonomi 《Earth Science Informatics》2009,2(1-2):5-21
GRIDA3 (Shared Resources Manager for Environmental Data Analysis and Applications) is a multidisciplinary project designed to deliver an integrated system to forge solutions to some environmental challenges such as the constant increase of polluted sites, the sustainability of natural resources usage and the forecast of extreme meteorological events. The GRIDA3 portal is mainly based on Web 2.0 technologies and EnginFrame framework. The portal, now at an advanced stage of development, provides end-users with intuitive Web-interfaces and tools that simplify job submission to the underneath computing resources. The framework manages the user authentication and authorization, then controls the action and job execution into the grid computing environment, collects the results and transforms them into an useful format on the client side. The GRIDA3 Portal framework will provide a problem-solving platform allowing, through appropriate access policies, the integration and the sharing of skills, resources and tools located at multiple sites across federated domains. 相似文献
942.
Economics of climate policy and collective decision making 总被引:1,自引:0,他引:1
Beat Bürgenmeier Andrea Baranzini Catherine Ferrier Céline Germond-Duret Karin Ingold Sylvain Perret Peter Rafaj Socrates Kypreos Alexander Wokaun 《Climatic change》2006,79(1-2):143-162
This paper explores the reasons why economic instruments of climate change are reluctantly applied and stresses the need for interdisciplinary research linking economic theory and empirical testing to deliberative political procedures. It is divided in three parts. The first one recalls the main issues in implementing Cost-Benefit Analysis such as information problems, uncertainties, discounting the future and irreversibilities. The second part shows how these issues can be treated in integrated assessment and techno-economic models and presents a case study, which shows that
- The chosen scenario tends to stabilize atmospheric CO2 concentration at around 550 ppm in the long run.
- Exclusion of possibility to trade CO2 emission permits under a cap regime would increase the cost of emission abatement for OECD countries.
- Combining different flexibility instruments might lead to significant gains in the overall cost of climate policy.
943.
Petr Dobrovolný Anders Moberg Rudolf Brázdil Christian Pfister Rüdiger Glaser Rob Wilson Aryan van Engelen Danuta Limanówka Andrea Kiss Monika Halíčková Jarmila Macková Dirk Riemann Jürg Luterbacher Reinhard Böhm 《Climatic change》2010,101(1-2):69-107
Monthly temperature series for Central Europe back to AD 1500 are developed from documentary index series from Germany, Switzerland and the Czech Republic (1500–1854) and 11 instrumental temperature records (1760–2007). Documentary evidence from the Low Countries, the Carpathian Basin and Poland are used for cross-checking for earlier centuries. The instrumental station records are corrected for inhomogeneities, including insufficient radiation protection of early thermometers and the urban heat island effect. For overlapping period (1760–1854), the documentary data series correlate with instrumental temperatures, most strongly in winter (86% explained variance in January) and least in autumn (56% in September). For annual average temperatures, 81% of the variance is explained. Verification statistics indicate high reconstruction skill for most months and seasons. The last 20 years (since 1988) stand out as very likely the warmest 20-year period, accounting for the calibration uncertainty and decreases in proxy data quality before the calibration period. The new reconstruction displays a previously unobserved long-term decrease in DJF, MAM and JJA temperature variability over last five centuries. Compiled monthly, seasonal and annual series can be used to improve the robustness of gridded large-scale European temperature reconstructions and possible impact studies. Further improvement of the reconstruction would be achieved if documentary data from other European countries are further developed. 相似文献
944.
On the Impact of Anthropogenic Heat Fluxes on the Urban Boundary Layer: A Two-Dimensional Numerical Study 总被引:2,自引:1,他引:1
Andrea Krpo Francisco Salamanca Alberto Martilli Alain Clappier 《Boundary-Layer Meteorology》2010,136(1):105-127
The heat generated in buildings and the manner in which this heat is exchanged with the ambient environment can play an important
role in urban climate. Recent studies have shown that anthropogenic heat from air-conditioning facilities can increase the
exterior ambient temperature and should be taken into account for a more complete urban heat island (UHI) mitigation study.
For this purpose, the first part of the present work is focused on the coupling of a new building energy model (BEM) and an
urban canopy parameterisation (UCP). The new scheme is implemented in a finite volume mesoscale model (MM) and tested in a
two-dimensional (2D) configuration of a city over flat terrain. A sensitivity study is performed with respect to different
parameters in order to test the simulation system and enhance the understanding of the possible impacts of the BEM on the
exterior microclimate. 相似文献
945.
Adriano Mazzarella Andrea Giuliacci Ioannis Liritzis 《Theoretical and Applied Climatology》2010,100(1-2):23-27
Many point indices have been developed to describe El Niño/Southern Oscillation, but the multivariate El Niño Southern Oscillation (ENSO) index (MEI) is considered the most representative since it links six different meteorological parameters measured over the tropical Pacific. Spectral analysis with appropriate data reduction techniques of monthly values of MEI (1950–2008) has allowed the identification of a large 60-month cycle, statistically confident at a level larger than 99%. The highest values of MEI (typical of El Niño events) and the lowest values of MEI (typical of La Niña events) are concordant with respective maxima and minima values of the identified 60-month cycle. 相似文献
946.
Ulrich Foelsche Michael Borsche Andrea K. Steiner Andreas Gobiet Barbara Pirscher Gottfried Kirchengast Jens Wickert Torsten Schmidt 《Climate Dynamics》2008,31(1):49-65
High quality observations of the atmosphere are particularly required for monitoring global climate change. Radio occultation
(RO) data, using Global Navigation Satellite System (GNSS) signals, are well suited for this challenge. The special climate
utility of RO data arises from their long-term stability due to their self-calibrated nature. The German research satellite
CHAllenging Minisatellite Payload for geoscientific research (CHAMP) continuously records RO profiles since August 2001 providing
the first opportunity to create RO based climatologies for a multi-year period of more than 5 years. A period of missing CHAMP
data from July 3, 2006 to August 8, 2006 can be bridged with RO data from the GRACE satellite (Gravity Recovery and Climate
Experiment). We have built seasonal and zonal mean climatologies of atmospheric (dry) temperature, microwave refractivity,
geopotential height and pressure with 10° latitudinal resolution. We show representative results with focus on dry temperatures
and compare them with analysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF). Although we have
available only about 150 CHAMP profiles per day (compared to millions of data entering the ECMWF analyses) the overall agreement
between 8 and 30 km altitude is in general very good with systematic differences <0.5 K in most parts of the domain. Pronounced
systematic differences (exceeding 2 K) in the tropical tropopause region and above Antarctica in southern winter can almost
entirely be attributed to errors in the ECMWF analyses. Errors resulting from uneven sampling in space and time are a potential
error source for single-satellite climatologies. The average CHAMP sampling error for seasonal zonal means is <0.2 K, higher
values occur in restricted regions and time intervals which can be clearly identified by the sampling error estimation approach
we introduced (which is based on ECMWF analysis fields). The total error of this new type of temperature climatologies is
estimated to be <0.5 K below 30 km. The recently launched Taiwan/U.S. FORMOSAT-3/COSMIC constellation of 6 RO satellites started
to provide thousands of RO profiles per day, but already now the single-satellite CHAMP RO climatologies improve upon modern
operational climatologies in the upper troposphere–lower stratosphere and can act as absolute reference climatologies for
validation of more bias-sensitive climate datasets and models. 相似文献
947.
948.
Narcisa Gabriela Pricope Lin Cassidy Andrea Elizabeth Gaughan Jonathan David Salerno Forrest Robert Stevens Joel Hartter 《社会与自然资源》2020,33(3):418-431
AbstractConducting research on coupled social-ecological systems (SESs) presents inherent challenges, such as coordination across disparate disciplines or integrating across multiple scales and levels of governance. To overcome these common challenges, we propose that structuring the research design itself according to SES principles provides for integrative execution of SES science. First, starting with pilot work, human and natural science researchers should work as a team to identify and access multi-level entry points (i.e. points of direct engagement) within the system, relative to the spatiotemporal scales under investigation. Second, teams should implement an adaptive process that begins with the proposed research design and uses shared experiences from pilot work to refine protocols prior to subsequent data collection. We provide examples of multi-level and multi-scale entry points, and show that adaptive management of research design through coordinated iteration allows for better research integration and applicable outcomes. 相似文献
949.
The Manso Glacier (~41°S, 72°W), in the northern Patagonian Andes of Argentina, is a regenerated glacier that, like many other glaciers in the region and elsewhere, has been showing a significant retreat. Glacial melt water feeds the Manso Superior River, which, before crossing the Andes to reach a Pacific outfall, flows through the Mascardi (a deep, oligotrophic and monomictic lake) and significantly smaller Hess and Steffen lakes. Harmonic analysis of Mascardi's lake level series suggests that the El Niño‐Southern Oscillation signal has been strong during the 1985–1995 decade but has grown weaker during the initial decade of the 21st century. Hydrological trend analyses applied in data recorded in the uppermost reaches show a monthly and annual decreasing trend in the Manso Superior River discharge series and Mascardi's lake level, which are connected with both, decreasing melt water discharge and (austral) wintertime atmospheric precipitation. Downstream, the decreasing signal initially looses statistical significance and then, when flowing through Steffen Lake, reverses the lake level trend that becomes significantly positive. This suggests that, on its way to the Pacific Ocean, the Manso River receives abundant Andean snow melt water and atmospheric precipitation, which are sufficient to obliterate the negative trend recorded in the uppermost reaches. The reason for this local phenomenon is that the Manso is an antecedent river (aka superposed stream), and hence, the valley crossing the Andes allows the incursion of Pacific humidity that modifies the hydrological regime several hundred kilometres inland. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
950.
This paper presents a novel formulation for defining soil failure. It plots in the principal stress space as a surface with the shape ranging between an approximation of the Matsuoka–Nakai and of the Mohr–Coulomb criteria depending on the value of a single parameter. The new function can be used as a replacement of the original equations of these well‐established criteria for implementing in a program for numerical analyses, and it is particularly effective for approximating the Matsuoka–Nakai criterion. Both the Mohr–Coulomb and the Matsuoka–Nakai failure criteria present numerical difficulties during implementation and also at run‐time. In the case of the Matsuoka–Nakai, the new formulation plots in the first octant only, whereas the original criterion plots in all octants, which causes severe convergence problems particularly for those Gauss points with low stress state, such as those on the side of a shallow footing. When the shape parameter is set to reproduce the Mohr–Coulomb failure criterion, on the other hand, the new formulation plots as a pyramid with rounded edges. Moreover, as the new function is at least of class C2, the second derivatives are continuous, thus ensuring quadratic convergence of the Newton's method used within the integration scheme of the constitutive law. The proposed formulation can also provide both sharp and rounded apex of the surface at the origin of the stress space by setting accordingly one additional parameter. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献