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361.
计算了地球扁率对月亮和太阳引潮力影响的量级,并对其空间分布特征、频率分布特征进行了分析,以及利用ELP2000-85星历计算了月亮引潮位中地球扁率影响项的调和展开.结果表明,引潮力中地球扁率的影响最大值接近2×10-11ms-2.引潮位调和展开结果中,振幅大于4×10-13ms-2的潮波项共有16项. 相似文献
362.
利用GAMIT/GLOBK软件,分别采用相似变换法和强约束法对扩展后的260个CGCS2000骨架网点的GNSS观测数据进行处理。按照3种方案进行平差获得站点在ITRF2008框架下的坐标,结果得出,使用强约束法时,起算数据的约束不同会引起定位结果的差异,不恰当的约束会造成精度的降低;相似变换法可以避免不恰当的约束引起的网的变形和扭曲,且可靠性更高,其平均中误差优于1 mm。 相似文献
363.
在Microsoft Access 2000中编辑制作的华南花岗岩数据库,由24张表格和相应的表单、部分查询组成,可以方便地实现花岗岩数据的管理和GeoKit、Mapgis等软件对数据的引用处理;界面友好,操作简单,是花岗岩类数据收录、管理与综合分析的有用工具. 相似文献
364.
Comparison of Methods Used to Estimate Conventional Undiscovered Petroleum Resources: World Examples
Various methods for assessing undiscovered oil, natural gas, and natural gas liquid resources were compared in support of
the USGS World Petroleum Assessment 2000. Discovery process, linear fractal, parabolic fractal, engineering estimates, PETRIMES,
Delphi, and the USGS 2000 methods were compared. Three comparisons of these methods were made in: (1) the Neuquen Basin province,
Argentina (different assessors, same input data); (2) provinces in North Africa, Oman, and Yemen (same assessors, different
methods); and (3) the Arabian Peninsula, Arabian (Persian) Gulf, and North Sea (different assessors, different methods). A
fourth comparison (same assessors, same assessment methods but different geologic models), between results from structural
and stratigraphic assessment units in the North Sea used only the USGS 2000 method, and hence compared the type of assessment
unit rather than the method. In comparing methods, differences arise from inherent differences in assumptions regarding: (1)
the underlying distribution of the parent field population (all fields, discovered and undiscovered), (2) the population of
fields being estimated; that is, the entire parent distribution or the undiscovered resource distribution, (3) inclusion or
exclusion of large outlier fields; (4) inclusion or exclusion of field (reserve) growth, (5) deterministic or probabilistic
models, (6) data requirements, and (7) scale and time frame of the assessment. Discovery process, Delphi subjective consensus,
and the USGS 2000 method yield comparable results because similar procedures are employed. In mature areas such as the Neuquen
Basin province in Argentina, the linear and parabolic fractal and engineering methods were conservative compared to the other
five methods and relative to new reserve additions there since 1995. The PETRIMES method gave the most optimistic estimates
in the Neuquen Basin. In less mature areas, the linear fractal method yielded larger estimates relative to other methods.
A geologically based model, such as one using the total petroleum system approach, is preferred in that it combines the elements
of petroleum source, reservoir, trap and seal with the tectono-stratigraphic history of basin evolution with petroleum resource
potential. Care must be taken to demonstrate that homogeneous populations in terms of geology, geologic risk, exploration,
and discovery processes are used in the assessment process.
The USGS 2000 method (7th Approximation Model, EMC computational program) is robust; that is, it can be used in both mature
and immature areas, and provides comparable results when using different geologic models (e.g. stratigraphic or structural)
with differing amounts of subdivisions, assessment units, within the total petroleum system. 相似文献
365.
The USGS has developed several mathematical models to forecast reserve growth of fields both in the United States (U.S.) and
the world. The models are based on historical reserve growth patterns of fields in the U.S. The patterns of past reserve growth
are extrapolated to forecast future reserve growth. Changes of individual field sizes through time are extremely variable,
therefore, the reserve growth models take on a statistical approach whereby volumetric changes for populations of fields are
used in the models. Field age serves as a measure of the field-development effort that is applied to promote reserve growth.
At the time of the USGS World Petroleum Assessment 2000, a reserve growth model for discovered fields of the world was not
available. Reserve growth forecasts, therefore, were made based on a model of historical reserve growth of fields of the U.S.
To test the feasibility of such an application, reserve growth forecasts were made of 186 giant oil fields of the world (excluding
the U.S. and Canada). In addition, forecasts were made for these giant oil fields subdivided into those located in and outside
of Organization of Petroleum Exporting Countries (OPEC). The model provided a reserve-growth forecast that closely matched
the actual reserve growth that occurred from 1981 through 1996 for the 186 fields as a whole, as well as for both OPEC and
non-OPEC subdivisions, despite the differences in reserves definition among the fields of the U.S. and the rest of the world. 相似文献
366.
367.
M. Malinowski A. ela
niewicz M. Grad A. Guterch T. Janik CELEBRATION Working Group 《Tectonophysics》2005,401(1-2):55-77
The CELEBRATION 2000 together with the earlier POLONAISE'97 deep seismic sounding experiments was aimed at the recognition of crustal structure in the border zone between the Precambrian East European Craton (Baltica) and Palaeozoic Europe. The CEL02 profile of the CELEBRATION family is a 400-km long SW–NE transect, running in Poland from the Upper Silesia Block (USB), across the Małopolska Block (MB) and the Trans-European Suture Zone (TESZ) to the East European Craton (EEC). The structure along CEL02 was interpreted using both 2D tomography and forward ray-tracing techniques as well as 2D gravity modelling.The crustal thickness along CEL02 varies from 32–35 km in the USB to 45–47 km beneath the TESZ and the EEC. The USB is a clearly distinctive crustal block with the characteristic high velocity lower crust (7.1–7.2 km/s), interpreted as a fragment of Gondwana. The Kraków–Lubliniec Fault is a terrane boundary produced by soft docking of the USB with the MB. The Małopolska crust fundamentally differs from the USB and has a strong connection with Baltica. It is a transitional, 150- to 200-km wide unit composed of the extended Baltican lower crust and the overlying low velocity (5.15–5.9 km/s) Neoproterozoic metasediments in the up to 18-km thick upper crust. The Łysogóry Unit has its crustal structure identical with that of Małopolska, thus it is connected with Baltica and cannot be interpreted as a Gondwana-derived terrane. Higher velocity and density bodies found below the Mazovia–Lublin Graben at a depth of 12 km and at the base of the lower crust, might be a result of mantle-derived mafic intrusions accompanying the extension of Baltica. By the preliminary 2D gravity modelling, we have reconfirmed the need for considering the increased TESZ mantle density in comparison to the EEC and USB mantle. 相似文献
368.
369.
The 2000 Hekla eruption took place from February 26 to March 8. Its seismic expressions were a swarm of numerous small earthquakes related to its onset, and low-frequency volcanic tremor that continued throughout the eruption. A swarm of small earthquakes was observed some 80 min before the onset of the eruption, and the size of the events increased with time. Low-frequency volcanic tremor, with a characteristic frequency band of 0.5–1.5 Hz and dominant spectral peak(s) at 0.7–0.9 Hz, became visible at 18:19 GMT on February 26, marking the onset of the eruption. The tremor amplitude rose quickly and was very high in the beginning of the eruption. However, it soon began to decrease after about an hour. In general, the seismic activity related to the 2000 Hekla eruption was very similar to what was observed in the previous eruption in 1991. Based on knowledge gained from seismicity and strain observations from 1991, this was the first time that a Hekla eruption was predicted.Editorial responsibility: J Stix 相似文献
370.
本文在简要叙述了GB/T19001-2000(idt ISO 9001:2000)质量管理体系的基础上,以测绘产品的质量控制为例论述了质量管理体系在测绘生产单位的具体应用。通过实施质量管理体系,实现对生产过程的质量控制,实现持续改进,不断地提高产品质量。 相似文献