移动Agent 在集群系统中的应用研究

从任务级的角度，在基于主／从模式的集群系统中引入了移动Agent技术，建立了基于移动Agent的并行计算模型。基于该模型，对移动Agent之间的通信接口、容错机制和负载平衡策略等问题进行了研究。     

三维地震勘探在构造复杂区的应用

三维地震勘探通过炮点与检波点的灵活组合,适合于复杂地表条件下地震勘探,从原理上也更加符合地质体的三维空间特性,有利于构造复杂的研究与探测.本文介绍的查庄煤矿就是利用三维地震勘探方法成功解决复杂构造问题的典型实例之一.     

On the sensitivity of computed surges to open-boundary formulation

A coarse-grid (resolution of order 7 km) model of the west coast of Britain is used to examine the sensitivity of computed storm-surge elevations and currents to a range of open-boundary conditions. The storm-surge period 1 to 26 March 1994 is used for this comparison, as it is a time of significant wind activity. Also current measurements in the North Channel of the Irish Sea together with coastal elevation measurements are available for model validation. Elevations and currents previously computed with a coarse-grid shelf-wide model can also be incorporated into the open-boundary condition to examine the influence of far-field effects. Initial model calculations with no far-field input show the importance of including shelf-wide effects from either the external shelf model, or by using observations from coastal gauges interpolated along the open boundary of the west-coast model. Provided the west-coast models open boundary is taken sufficiently far away from the region of interest, in this case the Irish Sea, then either a radiation condition or an elevation-specified condition is appropriate provided far-field effects are taken into account. If these are not included, then neither boundary condition is successful. For the radiation condition it is necessary to include both elevations and currents from a far-field model in order to reproduce the surge. In the case of an elevation-specified boundary condition far-field effects can be incorporated in hindcast calculations by including observed sea-level changes. In a storm-surge prediction calculation the radiation condition with a far-field model is required. Calculations show that computed elevations are spatially more coherent than currents, with flows through the western Irish Sea showing the greatest sensitivity to open-boundary formulation during storm events.Responsible Editor: Phil Dyke     

求解半变异函数的常用方法与新方法研究

半变异函数的获取既有人为主观求取法,又有运用数学工具客观求取法,但是后者是今后的主要趋势。笔者在前人工作的基础上,归纳出多项式回归法、线性规划法和目标规划法三种求解半变异函数的成熟方法,以及非线性回归理论直接求解法、进化计算和积分面积三种新兴方法,并总结出各种方法的优缺点。最后概括出计算权重的两种方法。     

Confocal laser scanning microscopy and Raman imagery of ancient microscopic fossils

Among all problems confronting the study of ancient permineralized (petrified) microscopic fossils, two stand out, the need for (1) accurate documentation of their three-dimensional morphology, and (2) direct analysis of their chemical composition and that of their surrounding mineral matrices. To address these problems we demonstrate the use of two techniques that we have recently introduced to Precambrian paleobiology: confocal laser scanning microscopy and Raman imagery. These techniques, both of which are non-intrusive and non-destructive, can provide data by which to characterize, in situ and at micron-scale resolution, the cellular and organismal morphology of thin section-embedded organic-walled fossils. In addition, Raman imagery provides direct analyses of the molecular–structural composition of the kerogenous components of such fossils and of their surrounding matrices, and a means to assess quantitatively the geochemical maturity of the preserved organics. Use of these techniques for studies of ancient microscopic fossils can provide information in three dimensions at high spatial resolution about their morphology and cellular anatomy, taphonomy and fidelity of preservation, composition and mode of preservation, and their biogenicity and syngenetic origin with the rocks in which they occur.     

土钉支护现场测试及三维数值模拟分析

在进行土钉轴力和边坡位移测试的基础上 ,进行了土钉支护的三维数值模拟研究 ,对边坡位移、土钉轴力、塑性区分布等分别作了较为深入的探讨 ,认识到土钉与土体相互作用形成了一个完整的支护体系 ;基坑失稳破坏并非传统意义上的土体和土钉的破坏 ,而是土钉支护体系的整体性破坏 ;土钉支护体系的形成正是通过土钉的分担作用、应力传递与扩散作用来实现的 ,这是土钉支护作用的实质.     

Concealed porphyry delineation based on nonlinear three-dimensional density-difference inversion: An example in the Beiya mine area,Western Yunnan,China

Intermediate acid-complex rock masses with low-density characteristics are the most important prospecting sign in the Beiya area, of western Yunnan province, and provide a physical basis for good gravity exploration. It is usually difficult to obtaining solutions in connection with actual geological situations due to the ambiguity of the conventional gravity-processing results and lack of deep constraints. Thus, the three-dimensional (3D) inversion technology is considered as the main channel for reducing the number of solutions and improving the vertical resolution at the current stage. The current study starts from a model test and performs nonlinear 3D density-difference inversion called “model likelihood exploration”, which performs 3D inversion imaging and inversion of the known model while considering the topographic effects. The inversion results are highly consistent with those of the known models. Simultaneously, we consider the Beiya gold mine in Yunnan as an example. The nonlinear 3D density-difference inversion technology, which is restricted by geological information, is explored to obtain the 3D density body structure below 5 km in the mine area, and the 3D structure of the deep and concealed rock masses are obtained using the density constraints of the intermediate-acid-complex rock masses. The results are well consistent with the surface geological masses and drilling-controlled deep geological masses. The model test and examples both show that the 3D density-difference nonlinear inversion technology can reduce inversion ambiguity, improve resolution, optimize the inversion results, and realize “transparency” in deeply concealed rock masses in ore-concentrated areas,which is useful in guiding the deep ore prospecting.     

一种改进的快速最小高差DEM匹配方法

利用最小高差(LZD)法进行DEM匹配时,当待匹配DEM的分辨率比参考DEM高时,确定的同名点中存在冗余,将导致计算冗余和效率降低。为解决上述问题,对LZD法确定同名点的模型进行改化,提出一种改进的基于最小高差原理的快速DEM匹配方法。该方法根据参考DEM的格网点确定同名点以避免冗余,并通过近似确定同名点及其高差,有效简化了计算过程。实验结果表明,该方法在保证较高的收敛速度和匹配精度的基础上,可有效提高计算效率,且计算效率不随待匹配DEM分辨率提高而降低,DEM间分辨率差异越大,方法的优势越明显。