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51.
52.
The Green's functions for a set of fully coupled linear equations governing thermal consolidation of a homogeneous isotropic material are presented. The Green's functions are evaluated for one, two and three spatial dimensions, and in the Laplace and real-time domains. The Green's functions are employed in a boundary integral analysis of a simple problem to demonstrate the influence of full coupling on the field quantities.  相似文献   
53.
Two analytic closed form solutions for the one-dimensional advection–dispersion equation are presented. These solutions take account of changes in surface concentration with time as mass is transported into the soil. The first solution is developed for the case of rapid landfill construction. The second solution considers a time-dependent mass input to the landfill. The use of these solutions is illustrated by a number of examples and it is shown that consideration of the finite mass of contaminant within the landfill can significantly affect the concentration profiles beneath the landfill.  相似文献   
54.
The theory developed in Part I of this paper is extended to apply to the consolidation of horizontally layered soils under both axially symmetric and general surface loading. The method again leads to a considerable reduction in the amount of core storage necessary for computer solution and can be implimented on a mini-computer.  相似文献   
55.
In this paper the settlement of a rigid foundation supported by a layer of clay which has been stabilized with stone columns is considered. The results of an analytic solution for the settlement, assuming no yield occurs in the clay or columns, have been presented in a previous publication. This solution is now used to develop an interaction analysis which takes account of yielding within the stone columns. This interaction analysis is based on a number of plausible assumptions regarding the behaviour of the clay and columns. In order to check the validity of these assumptions elasto-plastic finite element analyses have been performed and the agreement between the two methods is very good. However, the computational effort required for the finite element analyses is many orders of magnitude greater than that for the interaction analysis. This analysis has been used to generate a number of parametric solutions which provide a basis for estimating the reduction in settlement of the foundation due to the stabilization of the clay.  相似文献   
56.
In 1966 the expedition,' Carousel ' of the Scripps Institution of Oceanography called for three days at Easter Island and for a few hours at Juan Fernandez. The opportunity was taken to collect rock samples of known orientation for the determination of their ages and directions of magnetization. Owing to the shortness of the available time, the investigation was less thorough than was desirable. A Brunton compass was used to orient the samples.  相似文献   
57.
Robust estimation of geomagnetic transfer functions   总被引:22,自引:0,他引:22  
Summary. We show, through an examination of residuals, that all of the statistical assumptions usually used in estimating transfer functions for geomagnetic induction data fail at periods from 5 min to several hours at geomagnetic mid-latitudes. This failure can be traced to the finite spatial scale of many sources. In the past, workers have tried to deal with this problem by hand selecting data segments thought to be free of source effects. We propose an automatic robust analysis scheme which accounts for the systematic increase of errors with increasing power and which automatically downweights source contaminated outliers. We demonstrate that, in contrast to ordinary least squares, this automatic procedure consistently yields reliable transfer function estimates with realistic errors.  相似文献   
58.
A balloon-born multidirectional detector is used to measure the intensity variation of galactic and solar cosmic rays with the azimuthal angle, the zenith angle being maintained at 60°. In polar regions, the intensity towards the north is found to be 20% larger than that towards the south. It is shown that this anisotropy does not originate in interplanetary space and is not produced by a magnetospheric source. It is suggested that the effect is due to propagation effects within the magnetosphere.  相似文献   
59.
The presence of any leak in a waste repository is going to cause some concern since it may lead to the contamination of the surrounding soil and groundwater. This is an important problem which occurs and recurs, sometimes despite the precautions taken to minimize the possibility of development of any leak. The effects of contaminant leakage in general are not well understood. Thus it is the aim in this paper to develop some semi-analytical solutions of leakage problems occurring in deeply buried cylindrical repositories. In the solution approach, a series of integral transforms is used to simplify the governing equations and solutions are found in the transform space before numerical inversions are applied to obtain the contaminant concentrations in real space and time. To illustrate the application of the technique, results of some leakage cases are presented.  相似文献   
60.
The behaviour of an under-reamed anchor in a consolidating soil is examined by approximating the anchor as an impermeable circular plate embedded in a deep soil layer. Hankel and Laplace transforms are applied to the equations governing the consolidation process, and this greatly simplifies the equations, allowing a solution to be obtained for the transformed variables. Numerical inversion of both the Hankel and Laplace transforms is used to obtain the solution at any time. A particular feature of the solution method is that the unknown contact stress between the anchor and the soil and the unknown flows in the plane of the anchor are approximated as a series of simple functions with unknown coefficients. By determining the coefficients of the terms in the series, the complete solution may be found. Computations have been carried out using the method proposed, and results are presented for the time–settlement behaviour of an impermeable anchor. These results are compared with some published and some recomputed finite element data, and this highlights some of the difficulties encountered in using such numerical techniques.  相似文献   
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