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101.
最小生成树的高效异步并行算法 总被引:1,自引:0,他引:1
在MIMD-SM并行计算模型上,本文给出了时间复杂性为O(n(n/p+logp))的最小生成树的异步并行算法,其中n,p(1≤p≤n)分别表示图的顶点数和处理机的个数。 相似文献
102.
103.
In executing classical plans in the real world, small discrepancies between a planner's internal representations and the real world are unavoidable. These can conspire to cause real-world failures even though the planner is sound and, therefore, proves that a sequence of actions achieves the goal. Permissive planning, a machine learning extension to classical planning, is one response to this difficulty. This paper describes the permissive planning approach and presents GRASPER, a permissive planning robotic system that learns to robustly pick up novel objects. 相似文献
104.
本文对两激振器作反向回转的振动机控制同步进行了理论研究和计算机仿真。推导出了考虑质心偏移时两主轴的转矩差方程,在此基础上建立了控制系统的数学模型,设计了具有鲁棒性的非线性变结构滑模控制器.仿真结果表明,控制同步不仅可以消除由质心偏移、电机特性差等原因引起的稳态相位差,同时还能大大降低瞬态相位差,从而使机体的振动方向保持不变,减小起、制动过程中机体的摇摆振动. 相似文献
105.
With the growing size and complexity of power systems, system analysis—such as transients calculation—takes much time. Hence, fast calculation methods are required. Although parallel processing is a hopeful method, there have been difficulties in the parallel solution of linear equations which appear in power-flow calculations by the Newton-Raphson method. This paper aims at the fast calculation of the power-flow problem by means of parallel processing. In order to improve the suitability to the parallel solution of the differential equation in transients calculation, we assume the use of a direct-mapping parallel processing machine to map directly the network of a power system onto a network of processors. Under this assumption, we propose a new parallel-processing-oriented method in which the linear equation is solved by linear iterations between nodes with Aitken acceleration. We simulate the method on three model power systems and compare this Parallel Iterative Method (PIN) with a Parallel Direct Method (PDM) which uses the banded matrix according to the number of operations required. As a result, we can expect that PIM may solve linear equations faster than PDM with m processors, although the PIM might be inferior to the PDM with m × m processors, where m denotes the half-band width of the banded matrix. 相似文献
106.
107.
The conventional way of solving the group technology (GT) problem is to start from an assignment of parts to machines and try to find a partitioning of machine cells and part families. The similarity between parts is measured based on commonality of the machines assigned to them. However, parts are assigned to machines based on their operation requirements and the operation capabilities of machines. Similarity between parts should be based on their required operations. In this paper, the authors attempt to solve or facilitate solving the GT problem at the assignment level. An algorithm for assigning parts to machines is provided which utilizes the types of operations required by parts and applies GT principles in producing the assignment. This leads to better partitioning of machine cells and part-families. Furthermore, operation sequences required by parts in determining the similarity between parts have been considered. An algorithm to form part-families based on the operation sequence similarity coefficient has been developed. The resulting families are then used by the assignment algorithm to produce machine assignments to part-families. The use of the algorithm is demonstrated by examples. 相似文献
108.
109.
根据球面形成原理,利用铣刀和工件的两个圆运动,合成球头碗的不完整内球面。采用组合机床,结构简单,调整、维护方便,主轴弹性卡头便于工件装卸。对零件尺寸、形状和位置误差进行了分析。通过对铣刀和主轴电机的变频调速,找出最佳切削参数,实现了内球面的高效率高精度加工。 相似文献
110.
在已射孔的斜井压裂过程中,射孔孔眼处会出现一系列的几乎相互平行的雁形裂缝。这些裂缝的延伸、连接受到地层应力及裂缝本身的影响,情况较为复杂,但它们的延伸和连接对压裂的成功与否至关重要。笔者对裂缝模型进行简化,将复变函数理论与位错理论相结合,并且考虑了裂缝表面有流体压力作用且裂缝之间存在相互干扰的情况下,建立了无限大介质中裂尖应力强度因子的数学模型,利用该模型可对雁型裂缝之间的相互干扰进行力学分析。应用数值方法对所建立的数学模型求解,得到裂尖的应力强度因子及转角,来预测裂缝连接情况。该结果可用来指导压裂井的射孔施工。 相似文献