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181.
Vania Bogorny Chiara Renso Artur Ribeiro de Aquino Fernando de Lucca Siqueira Luis Otavio Alvares 《Transactions in GIS》2014,18(1):66-88
Several works have been proposed in the last few years for raw trajectory data analysis, and some attempts have been made to define trajectories from a more semantic point of view. Semantic trajectory data analysis has received significant attention recently, but the formal definition of semantic trajectory, the set of aspects that should be considered to semantically enrich trajectories and a conceptual data model integrating these aspects from a broad sense is still missing. This article presents a semantic trajectory conceptual data model named CONSTAnT, which defines the most important aspects of semantic trajectories. We believe that this model will be the foundation for the design of semantic trajectory databases, where several aspects that make a trajectory “semantic” are taken into account. The proposed model includes the concepts of semantic subtrajectory, semantic points, geographical places, events, goals, environment and behavior, to create a general concept of semantic trajectory. The proposed model is the result of several years of work by the authors in an effort to add more semantics to raw trajectory data for real applications. Two application examples and different queries show the flexibility of the model for different domains. 相似文献
182.
183.
In 1830, Libri announced the finding of a 16-year-long record of daily temperature observed in Florence, Italy, by Father Renieri before the activity of the Medici Network (1654 to 1670) that is usually considered the earliest instrumental series in the world. The Libri announcement was supported by the concurrent finding of a box with the early Little Florentine Thermometers that survived the Inquisition and was confirmed by Schouw, von Humboldt and Maxwell. However, all investigations made to find Renieri’s observations were fruitless. This paper clarifies this complex situation differentiating between myth and reality. A careful analysis of the Libri’s announcement in the historical context points out that Libri made the announcement while escaping for conspiracy from Florence and needed a scoop to be introduced in the French Academy of Sciences. For this reason he made a deliberate mix of new and old assertions, i.e. he claimed to have made new discoveries but without explaining too much and reporting misleading details about well known stories concerning the earliest meteorological observations. This induced people to suppose that further, earlier records existed. The consequence of this was that climatologists searched for years the claimed records. This paper shows that the Medici Network almost certainly contains the earliest exploitable instrumental observations. The possibility of finding a short series of observations prior to 1654 is remote. 相似文献
184.
Diana Dell’Arciprete Chiara Vassena Fulvia Baratelli Mauro Giudici Riccardo Bersezio Fabrizio Felletti 《Hydrogeology Journal》2014,22(4):761-778
In porous aquifers, groundwater flow and solute transport strongly depend on the sedimentary facies distribution at fine scale, which determines the heterogeneity of the conductivity field; in particular, connected permeable sediments could form preferential flow paths. Therefore, properly defined statistics, e.g. total and intrinsic facies connectivity, should be correlated with transport features. In order to improve the assessment of the relevance of this relationship, some tests are conducted on two ensembles of equiprobable realizations, obtained with two different geostatistical simulation methods—sequential indicator simulation and multiple point simulation (MPS)—from the same dataset, which refers to an aquifer analogue of sediments deposited in a fluvial point-bar/channel association. The ensembles show different features; simulations with MPS are more structured and characterised by preferential flow paths. This is confirmed by the analysis of transport connectivities and by the interpretation of data from numerical experiments of conservative solute transport with single and dual domain models. The use of two ensembles permits (1) previous results obtained for single realizations to be consolidated on a more firm statistical basis and (2) the application of principal component analysis to assess which quantities are statistically the most relevant for the relationship between connectivity indicators and flow and transport properties. 相似文献
185.
Margaret M. Hurwitz Natalia Calvo Chaim I. Garfinkel Amy H. Butler Sarah Ineson Chiara Cagnazzo Elisa Manzini Cristina Peña-Ortiz 《Climate Dynamics》2014,43(12):3367-3376
The seasonal mean extra-tropical atmospheric response to El Niño/Southern Oscillation (ENSO) is assessed in the historical and pre-industrial control CMIP5 simulations. This analysis considers two types of El Niño events, characterized by positive sea surface temperature (SST) anomalies in either the central equatorial Pacific (CP) or eastern equatorial Pacific (EP), as well as EP and CP La Niña events, characterized by negative SST anomalies in the same two regions. Seasonal mean geopotential height anomalies in key regions typify the magnitude and structure of the disruption of the Walker circulation cell in the tropical Pacific, upper tropospheric ENSO teleconnections and the polar stratospheric response. In the CMIP5 ensembles, the magnitude of the Walker cell disruption is correlated with the strength of the mid-latitude responses in the upper troposphere i.e., the North Pacific and South Pacific lows strengthen during El Niño events. The simulated responses to El Niño and La Niña have opposite sign. The seasonal mean extra-tropical, upper tropospheric responses to EP and CP events are indistinguishable. The ENSO responses in the MERRA reanalysis lie within the model scatter of the historical simulations. Similar responses are simulated in the pre-industrial and historical CMIP5 simulations. Overall, there is a weak correlation between the strength of the tropical response to ENSO and the strength of the polar stratospheric response. ENSO-related polar stratospheric variability is best simulated in the “high-top” subset of models with a well-resolved stratosphere. 相似文献
186.
This work examines the connection between Quaternary tectonics and erosion/incision processes in the primary Tuscan‐Romagna watershed of the Northern Apennines, which essentially coincides with the topographic culmination of the Nero Unit structural ridge. Tectonic and geomorphic information were collected in the area where this ridge is crossed by the upper Tiber River course forming a deep gorge. Structural analysis and field mapping have revealed that the region experienced polyphase tectonics with superposed thrust folding events identifiable both at the map and mesoscopic scales. Hinterland‐SSW‐verging thrusts and thrust‐related folds deformed the whole thrust pile during the latest deformation phase. Backthrusts/backfolds controlled the development of intermountain basins nearby the main watershed during the Early Pleistocene and seemingly deformed, in the Tiber gorge, a low‐relief landscape developed in the Early Pleistocene (ca. 1.1 Ma). Successively, the upper Tiber River course area and Apennines axial zone underwent a generalized uplift, which is manifested by the deep incision of palaeo‐morphologies. This proposed sequence of events correlates well with the major geodynamic change of the Apennines revealed by an acceleration of uplift rates in the Middle–Late Pleistocene. This latter event may also correlate with increased rates of river incision recorded in Europe as a consequence of uplift and/or climate change. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献