基于贝叶斯推论的致密储层水力单元预测表征技术

针对小壕兔-大16井区储层结构复杂、有利区预测困难的问题,运用贝叶斯挖掘算法,利用计算机辅助模拟手段,构建研究区精细水力单元模型,探明储层砂体发育规律。研究结果表明,基于贝叶斯推论的表征技术能高效识别储层水力单元类型,为气藏描述提供准确的地质信息;指数函数递增法在测井曲线划段过程中表现更加出色,R_t测井段间样点的聚簇规律归因于储层的高含水特性;3类水力单元具有较大的原始油气储量和潜力,亦是提高气藏采收率过程中亟待突破的对象。该研究成果对预测储层有利区具有重要参考价值。     

帕累托最优在车辆底部防护结构设计中的应用研究

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基于基准线概率密度的多站多目标定位

针对在多传感器多目标定位中,运用测向交叉定位法会产生大量虚假点,研究了一种剔除虚假点的方法。首先确定一个基准站,将其所测角度对应的测向线设为基准线,其他站测角所对应的测向线与每条基准线相交可产生大量交点,通过比较每条基准线上交点的概率密度和,选取和值最大点作为对应基准线上目标的估计位置。仿真分析表明,此法定位精度高,处理速度快,适于实时处理。     

二维几何构形

本文讨论由多个零件组成的两组任意平面图形进行并、交、差、外延和内含等5类运算的算法:各零件之间的相对位置关系,归结为相交、分离、内含和重合等4种状态的任意组合;而零件则由内环、外环和虚环等构成;将圆弧作为基本元素直接参加运算。提出并解决了“奇异重点”、“第二类奇异重点”和“虚环”等问题;整个工作成功地与Auto CAD进行了联接。     

参数型非空交定理及其在变分不等式理论中的应用

在已经证明的广义区间空间中几个参数型非空交定理的基础上，利用这些结果得到了广义区间空间中变分不等式解的存在性定理。这一研究成果推广了ＹｅｎＣＬ１９８１年所发表的“极大极小定理及其在变分不等式中的应用”一文中的定理３。     

基于一种新的混合算法的交通流控制优化模型

运用交通流控制理论建立了在交叉口空间渠化及信号相位相序给定的条件下, 考虑机动车与非机动车的延误（服务水平）约束条件, 机动车通行能力最大的优化模型, 并利用遗传算法及混沌优化算法互补的混合优化算法对模型进行了优化计算. 实际优化计算结果表明, 文中的优化模型及其混合算法具有较高的理论价值及实用价值, 本次研究为信号交叉口交通流的协调控制优化研究提供了新思路和新方法.     

Implementation and Field Testing of Characteristics-Based Intersection Queue Estimation Model

This paper proposes and implements a dynamic queue length estimation model at signalized intersections. Based on the continuum principle, this model describes the formation and dissipation of traffic queues at an intersection and the interactions with the signals. The use of a general speeddensity relationship in the model leads to the development of a general mathematical formulation for intersection queue length studies, which allows the model to adapt to changes in traffic and geometric conditions through parameter updating. Field testing of the model has demonstrated initial success. Experience suggests that use of headway and average speed data in density derivation lead to more stable and accurate results than using other traffic data.     

Theoretically-based algorithms for robustly tracking intersection curves of deforming surfaces

This paper applies singularity theory of mappings of surfaces to 3-space and the generic transitions occurring in their deformations to develop algorithms for continuously and robustly tracking the intersection curves of two deforming parametric spline surfaces, when the deformation is represented as a family of generalized offset surfaces. The set of intersection curves of two deforming surfaces over all time is formulated as an implicit 2-manifold I in an augmented (by time domain) parametric space R⁵. Hyperplanes corresponding to some fixed time instants may touchI at some isolated transition points, which delineate transition events, i.e. the topological changes to the intersection curves. These transition points are the 0-dimensional solution to a rational system of five constraints in five variables, and can be computed efficiently and robustly with a rational constraint solver using subdivision and hyper-tangent bounding cones. The actual transition events are computed by contouring the local osculating paraboloids. Away from any transition points, the intersection curves do not change topology and evolve according to a simple evolution vector field that is constructed in the Euclidean space in which the surfaces are embedded.     

采用"结式法"的圆环面和球面求交算法

提出了一种不需跟踪的求交算法.通过坐标变换使圆环中心轴与球心共处在XOZ平面内,然后讨论该平面内圆环面小圆和球面截圆的位置关系,给出了圆环面和球面不相交、交线为一个或两个圆、有孤立交点的几何条件以及交线的区间.最后,将圆环面和球面求交转化为平行于XOY面的平面内的两圆交点的问题并利用"结式法"解得交点.