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注水油田年综合含水率预测的数学模型 总被引:1,自引:0,他引:1
本文将改进的灰色GM(1,1)模型用于某油田年综合含水率的近期发展趋势研究。在平均相对误差达到最小准则下,研究了模型中的背景值参数A和边值修正项£对模型预测精度的影响。在此基础上,采用线性规划方法估计模型中的参数,基于遗传算法求解最佳背景值参数A和最佳边值修正项ε,以确保在相应的模型检验准则下预测的误差达到最小。结果表明,用改进的灰色GM(1,1)模型预测近期注水油田的综合含水率,预测值与实际值相对误差很小,预测精度很高,可以得到非常满意的结果。进一步的研究发现,改进的灰色GM(1,1)模型虽然近期预测精度很高,但研究长期的发展趋势是行不通的,为此又研究探讨了长期发展趋势模型。 相似文献
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The boundary measure method is applied to transfer the form of the integral equation in order to use the collocation method or Galerkin method. A simple way to computer the coefficients of the wavelet series is also introduced. The way presented in this paper can be used to solve PDE problem in the two dimension region with any form of boundary. 相似文献
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用改进的区间样条小波配点法求解Burgers方程 总被引:1,自引:0,他引:1
提出了一种用两个一阶导数矩阵的乘积替代二阶导算子矩阵的新算法,用两种不同的区间样条件小波插值算法对含不同参数的Burgers方程进行了验算,结果表明,对于稍大粘性系数的Burgers方程,替代算法的震荡明显小于原算法,因而替代算法有较大的稳定性范围。 相似文献
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The processes of the sudden energy release and energy transfer, and particle accelerations are the most challenge fundamental problems in solar physics as well as in astrophysics. Nowadays, there has been no direct measurement of the plasma parameters and magnetic fields at the coronal energy release site. Under the certain hypothesis of radiation mechanism and transmission process, radio measurement is almost the only method to diagnose coronal magnetic field. The broadband dynamic solar radio spectrometer that has been finished recently in China has higher time and frequency resolutions. Thus it plays an important role during the research of the 23rd solar cycle in China. Sometimes when there were very large bursts, the spectrometer will be overflowed. It needs to take some special process to discriminate the instrument and interference effects from solar burst signals. According to the characteristic of the solar radio broadband dynamic spectrometer, we developed a nonlinear calibration method to deal with the overflow of instrument, and introduced channel-modification method to deal with images. Finally the interference is eliminated with the help of the wavelet method. Here we take the analysis of the well-known solar-terrestrial event on July 14th, 2000 as the example. It shows the feasibility and validity of the method mentioned above. These methods can also be applied to other issues. 相似文献
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太阳射电爆发中观测到的纤维精细结构携带着爆发初期磁场活动的小尺度信息.对原始的纤维结构观测资料进行算法处理,分析纤维结构的重要特征———频率漂移率.利用小波变换提取宁静太阳背景信息,用原始频谱图减去背景并经过阈值处理,纤维结构被很好地分离出来,然后在每个通道上找出构成纤维结构的连续片断,利用三次样条插值法对每个连续片断拟合其时间-强度关系,确定最大强度对应的时间,用线性回归方法计算纤维结构的频漂率.对2002年4月21日的一组纤维结构事件进行计算,得出其平均频漂率在-0.041 0~-0.013 8 GHz.s-1之间. 相似文献