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101.
102.
韩国强 《高校应用数学学报(A辑)》1994,(3)
本文我们讨论了矩形域上带连续边界条件的一类多元散乱数据最优插值。给出了某些情形插值的误差估计,误差估计表明在某些点上还具有超收敛性。 相似文献
103.
B. F. Whiting B. L. Coldwell S. M. Scott B. J. Evans D. E. McClelland 《General Relativity and Gravitation》2000,32(3):411-423
This work incorporates a review of the status, in Australia, of data analysis for gravitational wave detection using laser interferometers, within an overview of the present state of such research in the world generally. In this context, data analysis refers not so much to signal simulation as to what might be called the thorough process of noise characterization and the subsequent, quality-controlled signal extraction. To the extent that problems identified here arise for all currently planned instruments, there is necessarily a global component to the discussion presented. In Australia, there are unique circumstances, associated with attempting to carry out work in gravitational wave detection, which demand also a local aspect to the ensuing discussion. 相似文献
104.
In this paper, we introduce a recommendation session and propose a data structure (recommendation Patricia) which is used to accomplish fast searches in a recommendation session. The time cost for a search in each recommendation step is O(E * s2) if a recommendation Patricia is used, where E is the maximal length of words involved and s is the maximal size of each recommendation. In contradistinction, the worst-case time cost for the same goal is Ω(n) if a Patricia is used, where n is the number of words involved. 相似文献
105.
Advanced Genetic Programming Based Machine Learning 总被引:1,自引:0,他引:1
Stephan Winkler Michael Affenzeller Stefan Wagner 《Journal of Mathematical Modelling and Algorithms》2007,6(3):455-480
A Genetic Programming based approach for solving classification problems is presented in this paper. Classification is understood
as the act of placing an object into a set of categories, based on the object’s properties; classification algorithms are
designed to learn a function which maps a vector of object features into one of several classes. This is done by analyzing
a set of input-output examples (“training samples”) of the function. Here we present a method based on the theory of Genetic
Algorithms and Genetic Programming that interprets classification problems as optimization problems: Each presented instance
of the classification problem is interpreted as an instance of an optimization problem, and a solution is found by a heuristic
optimization algorithm. The major new aspects presented in this paper are advanced algorithmic concepts as well as suitable
genetic operators for this problem class (mainly the creation of new hypotheses by merging already existing ones and their
detailed evaluation). The experimental part of the paper documents the results produced using new hybrid variants of Genetic
Algorithms as well as investigated parameter settings. Graphical analysis is done using a novel multiclass classifier analysis
concept based on the theory of Receiver Operating Characteristic curves.
The work described in this paper was done within the Translational Research Project L282 “GP-Based Techniques for the Design
of Virtual Sensors” sponsored by the Austrian Science Fund (FWF). 相似文献
106.
RS和GIS技术在新疆地质和矿产资源评价中的应用 总被引:1,自引:0,他引:1
发展宏观、快速、高效地资源管理及评价方法是开展现代地质找矿工作的需要,“3S”技术由于具有上述特点而在地质找矿领域得到越来越广泛的应用。本文针对新疆地质找矿现状,通过对“3S”技术特点的介绍,在以往新疆地质找矿工作的基础之上,系统的提出了在新疆运用RS和GIS技术建立遥感本底数据库及进行矿产资源评价、地质灾害预测的主要内容、方法,同时指出了存在的问题和发展前景。 相似文献
107.
智能电网技术的发展,使得传统电力系统的规模及复杂度大大增加,同时产生了大量的用电数据,如何有效利用数据挖掘技术,从这些海量数据中挖掘出有潜在价值的信息,成为了当前电力系统分析中的一个挑战性问题。首先根据不同的时间段,将用户的用电数据进行划分,在分析每段时间内用户用电数据的基础上,采用KL-divergence(KL-散度)方法衡量用户差异,并结合基于密度改进的K-means算法,给出了一种新的用户特征提取算法,用以描述电网用户的特征差异,从而实现针对不同类别用户制定不同电力营销策略,这在一定程度上能够提高企业经济效益。最后,算例仿真结果表明,所给出的用户特征提取算法在计算的时间效率和准确性上,较传统方法都有了明显的提升。 相似文献
108.
针对目前各行业数字化、智能化产品应用日趋广泛,数据的获取、传输、分析、应用尤为重要,如何避免采集设备接口单一、功能固定、实用性差等缺点,提出采用ARM嵌入式工控模块M9080-N20为基础,采用VK3266串口芯片扩展UART串行接口,提出基于73K222AU调制解调器、HR219307变压器实现采集器二线模拟通信,并支持以太网、CAN总线和UART串行通信,可以有效解决数据远程采集、传输和控制,适用于特殊环境设备故障检测、诊断和抢修。实验结果证明,智能数据采集器不仅具有多种型号设备故障诊断功能;还能实现野外快速通信组网,不同类型设备数据远程采集、传输、分析和控制功能,在军民融合产品上具有广阔的应用前景和实用价值。 相似文献
109.
An iterative resolution method for inverse Cauchy problems is presented. The successive iterations satisfy the equilibrium equations exactly. Numerical simulations prove the accuracy of the method and its ability to solve Cauchy problems when the domain boundary is not regular. To cite this article: A. Cimetière et al., C. R. Mecanique 333 (2005). 相似文献
110.
Data reconciliation considers the restoration of mass balance among the noise prone measured data by way of component adjustments for the various particle size or particle density classes or assays over the separating node. In this paper, the method of Lagrange multipliers has been extended to balance bivariate feed and product size-density distributions of coal particles split from a settling column. The settling suspension in the column was split into two product fractions at 40% height from the bottom after a minute settling of homogenized suspension at start. Reconciliation of data assists to estimate solid flow split of particles to the settled stream as well as helps to calculate the profiles of partition curves of the marginal particle size or particle density distributions. In general, Lagrange multiplier method with uniform weighting of its components may not guarantee a smooth partition surface and thus the reconciled data needs further refinement to establish the nature of the surface. In order to overcome this difficulty, a simple alternative method of reconciling bivariate size-density data using partition surface concept is explored in this paper. 相似文献