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111.
Bi Xunqiang 《大气科学进展》1997,14(4):569-572
ParalelComputingofaClimateModelontheDawn1000byDomainDecompositionMethod①BiXunqiang(毕训强)InstituteofAtmosphericPhysics,ChineseA... 相似文献
112.
为了寻求一种操作简单、低成本的岩体应力测试方法, 本文提出了一个依据控制致裂钻孔应力变化的量测推算原岩应力的改进平行钻孔法。本文阐明了平行钻孔法岩体应力量测的特点和控制致裂法的原理。介绍了依据控制致裂钻孔应力变化确定岩体应力的基本理论。 相似文献
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114.
Guiyun Zhou Xiaoli Liu Suhua Fu Zhongxuan Sun 《International journal of geographical information science》2017,31(6):1061-1078
With the increasing sizes of digital elevation models (DEMs), there is a growing need to design parallel schemes for existing sequential algorithms that identify and fill depressions in raster DEMs. The Priority-Flood algorithm is the fastest sequential algorithm in the literature for depression identification and filling of raster DEMs, but it has had no parallel implementation since it was proposed approximately a decade ago. A parallel Priority-Flood algorithm based on the fastest sequential variant is proposed in this study. The algorithm partitions a DEM into stripes, processes each stripe using the sequential variant in many rounds, and progressively identifies more slope cells that are misidentified as depression cells in previous rounds. Both Open Multi-Processing (OpenMP)- and Message Passing Interface (MPI)-based implementations are presented. The speed-up ratios of the OpenMP-based implementation over the sequential algorithm are greater than four for all tested DEMs with eight computing threads. The mean speed-up ratio of our MPI-based implementation is greater than eight over TauDEM, which is a widely used MPI-based library for hydrologic information extraction. The speed-up ratios of our MPI-based implementation generally become larger with more computing nodes. This study shows that the Priority-Flood algorithm can be implemented in parallel, which makes it an ideal algorithm for depression identification and filling on both single computers and computer clusters. 相似文献
115.
This paper describes an implementation of a highly scalable parallel computational facility with high speedup efficiency using relatively low-cost hardware, which consists of a cluster of desktop personal computers (PCs) connected via a 10-Gigabit Ethernet. Two-levels of parallelization were implemented. Communication between different PCs was achieved using message passing interface (MPI) protocol. Domain decomposition was automated and based on element numbering. Domain continuity was assured largely by re-numbering the elements using a “front squasher” code prior to decomposition. Within each PC, the shared memory parallelization was implemented using either the open-multiprocessing (OpenMP) or the MPI protocol. Analysis of three different problems with number of degrees-of-freedom ranging from about 129,000 to about 2,260,000 shows a speedup efficiency generally above 70%. Super-linear speedup was achieved in several of the cases examined in this study, with the hybrid MPI-OpenMP approach generally performing better compared to the pure MPI method for parallelization. The results demonstrate the feasibility of acquiring a parallel computing facility with relatively modest outlay that is within the reach of consulting or engineering offices. 相似文献
116.
本文根据103个新疆气象台站DSG5型降水现象仪自动观测数据与人工观测数据进行对比分析探讨,获得了降水现象仪主要性能的整体情况,揭示出降水现象仪降水类型识别能力的个体差异;通过对比结果,给出疑误结果及产生原因,全面了解降水现象仪的技术指标和仪器性能,旨在为生产仪器厂家提供信息。同时,结合本地出现的特殊情况,给出确定可信的解决方案,为新疆正在开展的降水现象自动观测提供技术参考,以获取更加科学可信的气象数据。 相似文献
117.
Deformation control is a central problem in earth-rockfill dam design. The finite element method (FEM) is the primary method used to analyze and predict the deformation of earth-rockfill dams. The parameters of the constitutive model of soil used in earth-rockfill dams determine the FEM analysis results. Using prototype monitoring displacements, the soil parameters of the Malutang II concrete face rockfill dam were back-analyzed using parallel mutation particle swarm optimization. The calculated displacements of the back-analyzed soil parameters are consistent with the prototype monitoring results. The parallel mutation particle swarm optimization has a high optimization rate and can be used in large-scale practical engineering applications. The back-analysis results indicate that the deformation moduli of rockfills in the Malutang II are affected by construction situ. 相似文献
118.
The material point method (MPM), which is a combination of the finite element and meshfree methods, suffers from significant computational workload due to the fine mesh that is required in spite of its advantages in simulating large deformations. This paper presents a parallel computing strategy for the MPM on the graphics processing unit (GPU) to boost the method’s computational efficiency. The interaction between a structural element and soil is investigated to validate the applicability of the parallelisation strategy. Two techniques are developed to parallelise the interpolation from soil particles to nodes to avoid a data race; the technique that is based on workload parallelisation across threads over the nodes has a higher computational efficiency. Benchmark problems of surface footing penetration and a submarine landslide are analysed to quantify the speedup of GPU parallel computing over sequential simulations on the central processing unit. The maximum speedup with the GPU used is ∼30 for single-precision calculations and decreases to ∼20 for double-precision calculations. 相似文献
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120.
本文提出了一种用于模拟非轴对称套管井中扇区水泥胶结测井100 kHz 3维瞬态声场的并行算法.采用时域有限差分方法,以及非裂化的完全匹配层吸收边界条件,基于信息传递接口(MPI)并行环境,在计算机集群上实现并行计算.对内边界上的差分方程进行参数平均处理,提高了计算稳定性.通过在轴对称情况下将有限差分模拟结果与实轴积分法计算结果对比,验证了方法的正确性.使用并行有限差分算法,模拟了水泥环有不同大小和在不同方位缺失时非轴对称套管井中8扇区的扇区水泥胶结测井仪的测井波形,并分析了套管波幅度随水泥缺失-换能器夹角的变化.根据模拟和分析结果,得到了非轴对称套管井中新的声场传播规律,并建议了一种用于反演水泥缺失大小和方位的方法. 相似文献