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María-Jesús Lobo Caroline Appert Emmanuel Pietriga 《International journal of geographical information science》2017,31(9):1818-1845
GIS software applications and other mapping tools enable users to correlate data from multiple layers and gain insight from the resulting visualizations. However, most of these applications only feature basic, monolithic layer compositing techniques. These techniques do not always support users effectively in their tasks, as we observed during interviews with GIS experts. We introduce MapMosaic, a novel approach based on dynamic visual compositing that enables users to interactively create and manipulate local composites of multiple vector and raster map layers, taking into account the semantics and attribute values of objects and fields in the compositing process. We evaluate MapMosaic ’s interaction model against that of QGIS (a widely used desktop GIS) and MAPublisher (a professional cartography tool) using the ‘Cognitive Dimensions’ framework and through an analytical comparison, showing that MapMosaic ’s model is more flexible and can support users more effectively in their tasks. We also report on feedback obtained from experts, which further confirms the potential of this highly dynamic approach to map layer compositing. 相似文献
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K. R. Sreenivasan R. R. Prasad C. meneveau R. Ramshankar 《Pure and Applied Geophysics》1989,131(1-2):43-60
We describe scalar interfaces in turbulent flowsvia elementary notions from fractal geometry. It is shown by measurement that these interfaces possess a fractal dimension of 2.35±0.05 in a variety of flows, and it is demonstrated that the uniqueness of this number is a consequence of the physical principle of Reynolds number similarity. Also, the spatial distribution of scalar and energy dissipation in physical space is shown to be multifractal. We compare thef() curves obtained from one- and two-dimensional cuts in several flows, and examine their value in describing features of turbulence in the three-dimensional physical space. 相似文献
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二维反射地震成象—界面与速度的联合反演 总被引：8，自引：0，他引：8
介绍了利用反射走时联合反演地震界面起伏形态和速度横向分布的方法。正问题采用了一种简单而有效的二维介质中两点射线追踪方法，反问题在广义最小二乘意义下求解，描述界面和速度的两类参数不必要先进行分离，数值模拟的结果表明方法是有效的。处理了通过唐山震区的各庄－丰南－丰宁深地震测深剖面，得到了意义的结果。 相似文献
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背斜-水动力复合油(气)藏油(气)水界面产状 总被引：1，自引：1，他引：0
基于Hubbert的油(气)等势面坡度与水头关系的公式和达西定律, 推出了油(气)等势面坡度与水流的渗滤速度的关系式.根据此关系式, 讨论了各种情形水流速度与油气等势面坡度的关系.以此为基础, 认为未被油气充满转折端的背斜-水动力油气藏平面的油水界面由于水流速度大小和方向变化通常应该为曲面; 对被油气充满转折端的背斜-水动力油气藏倾斜的油水界面在不同方向剖面上倾斜不同: 圆柱状背斜横剖面油水界线水平、斜向剖面界线倾向相反, 倾伏背斜的横剖面可能同向倾斜但通常不在同一条倾斜的直线上. 相似文献
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A constitutive model to describe viscoplastic or time-dependent behaviour of interface materials is presented. Viscoplastic characteristics of the interface material are modeled based on Perzyna's theory of viscoplasticity and the Hierarchical Single Surface (HiSS) series of constitutive models. Experiments performed using a new interface test device to characterize the behaviour of cohesive soil–rock interfaces are described. Procedures to derive model parameters are presented together with validation of the model. Finite element implementation of the interface element is described along with verification of the model with respect to field behaviour of a creeping natural slope. 相似文献
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通过钻(冲)孔嵌岩灌注桩工程施工的实例,介绍在施工过程中对持力层岩面判断与嵌入岩层深度的控制方法,以及清除孔底沉渣工艺流程,并分析嵌岩桩在施工过程中遇到质量问题应采取的技术措施。 相似文献
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We present fully-discrete procedures for computing the impedance functions of rigid massless soil-structure interfaces that are embedded in arbitrarily heterogeneous half-spaces. The finite element method (FEM) is used for obtaining the wave responses of (visco-)elastic half-spaces truncated by Perfectly Matched Layers (PMLs), which provide the wave absorbing boundary conditions. The devised FEM-PML approach is verified in both time and frequency domains by using various benchmark solutions. Requirements on the prescribed input excitations for obtaining accurate impedances in the time domain as well as the relative computational cost of time- and frequency domain solutions are investigated. Accuracy of the implemented PMLs in extracting the impedance functions is also examined in comparison to Lysmer–Kuhlemeyer dashpots; and it was found that this simplified boundary treatment is generally inadequate. The utility of the proposed method is demonstrated by extracting the impedance matrix of rectangular and circular voids embedded in a linearly stiffening half-space. Impedance functions for such complex soil-structure systems are shown to be highly coupled and frequency-dependent due to wave reflections and interference caused by the soil heterogeneity and interface geometry. Fully discrete approaches, such as those proposed herein, are necessary to adequately capture these effects. 相似文献
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冲击波物理在地球和行星科学研究中的应用 总被引：3，自引：0，他引：3
概要介绍了冲击波物理应用于地球和行量科学研究中所取得的一些最新成果。主要涉及地球深部物质的组成，性质和状态，行星的组成模型，以及太阳系中的碰撞成坑和吸积相互作用等领域。着重论述了冲击波物理在这些领域的研究中所发挥的作用。 相似文献
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