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141.
The Design of Discrimination Experiments 总被引:1,自引:0,他引:1
Experimentation plays a fundamental role in scientific discovery. Scientists experiment to gather data, investigate phenomena, measure quantities, and test theories. In this article, we address the problem of designing experiments to discriminate between two completing theories. Given an initial situation for which the two theories make the same prediction, the experiment design problem is to determine how to modify the situation such that the two theories make different predictions for the modified situation. The modified situation is called a discrimination experiment. We present a knowledge-intensive method called DEED for designing discrimination experiments. The method analyzes the differences in the two theories' explanations of the prediction for the initial situation. Based on this analysis, it determines modifications to the initial situation that will result in a discrimination experiment. We illustrate the method with the design of experiments to discriminate between several pairs of qualitative theories in the fluids domain. 相似文献
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143.
本文利用模糊集理论,提出一种非确定环境的描述方法,并且针对机器人在该类环境中的避障轨迹规划,建立了相应的决策函数和规划策略,最后,给出在PC-386计算机上的仿真试验结果。 相似文献
144.
In this paper, a sensor system, called a fuzzy pulse discriminator, is developed to classify various discharge pulses in electrical discharge machining (EDM). The fuzzy rules of the pulse discriminator are obtained based on the features of the gap voltage and gap current between the tool workpiece. The membership functions of the fuzzy pulse discriminator are automatically synthesized by using genetic algorithms. The effectiveness of this approach is verified under different cutting parameters. 相似文献
145.
We derive a general equation relating probability densities and as special cases we the obtain Gram-Charlier and Edgeworth series. This allows us to generalize these methods and clarify a number of issues pertaining to both probability theory and time-frequency analysis. In particular we show how the Gram-Charlier and Edgeworth series are related to the kernel method of time-frequency analysis. The approach allows us to construct densities that satisfy given constraints such as joint moments or conditional moments. Also, we show that the kernel has to be signal dependent and that to obtain a proper distribution it should be the ratio of two characteristic functions. 相似文献
146.
147.
在对Sirius叠前深度偏移软件应用开发的基础上,分析讨论了Sirius 2D叠前深度偏移速度模型建立、层析成像及演、叠前深度偏移以及深度聚焦等技术环节的基本原理,并以莺歌海盆地某测线的处理为例,具体分析了Sirius 2D叠前深度偏移处理的流程、主要参数及时效.文中还分析讨论了莺歌海盆地中央“泥拱带”叠前深度偏移处理的地质效果.实践表明,莺歌海盆地广泛发育的与“泥拱模糊带”有关的构造各有其特殊性,只有通过3D叠前深度偏移处理才能从根本上解决“泥拱模糊带”的成像问题. 相似文献
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149.
Uwe Helmke Robert C. Williamson 《Mathematics of Control, Signals, and Systems (MCSS)》1995,8(1):27-49
The problem of parametrizing single hidden layer scalar neural networks with continuous activation functions is investigated. A connection is drawn between realization theory for linear dynamical systems, rational functions, and neural networks that appears to be new. A result of this connection is a general parametrization of such neural networks in terms of strictly proper rational functions. Some existence and uniqueness results are derived. Jordan decompositions are developed, which show how the general form can be expressed in terms of a sum of canonical second order sections. The parametrization may be useful for studying learning algorithms.This work was supported by the Australian Research Council, the Australian Telecommunications and Electronics Research Board, and the Boeing Commencai Aircraft Company (thanks to John Moore). 相似文献
150.
Counting Objects 总被引:1,自引:0,他引:1