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101.
偏最小二乘回归在渗流监控模型中的应用 总被引:1,自引:0,他引:1
在渗流监控指标中,库水位之间、库水位与降雨之间存在严重的相关性.利用普通多元线性回归建立渗流监控模型中,监控指标之间存在的多重相关性影响参数估计,扩大模型误差,破坏模型的稳健性.为了克服多重相关性对模型的干扰,引入了能辨别系统信息与噪声的偏最小二乘回归,并编制了程序.算例分析表明,偏最小二乘回归模型所分离出的各个影响分量能对大坝实测变量的变化作出合理的物理成因解释,而且偏最小二乘回归模型的预测能力也远优于普通最小二乘回归模型,前者的预测误差平方和约只有后者的二十分之一. 相似文献
102.
Xishu Wang Lina Zhang Yanping Zeng Xishan Xie 《北京科技大学学报(英文版)》2006,13(3):244-249
The low-cycle fatigue behavior of powder metallurgy Rene95 alloy containing surface inclusions was investigated by in-situ observation with scanning electron microscopy (SEM). The process of fatigue crack initiation and early stage of propagation behavior indicates that fatigue crack mainly occurs at the interface between the inclusion and the matrix. The effect of inclusion on the fatigue crack initiation and the early stage of crack growth was very obvious. The fatigue crack growth path in the matrix is similar to the shape of inclusion made on the basis of fatigue fracture image analysis. The empiric relation between the surface and inside crack growth length, near a surface inclusion, can be expressed. Therefore, the fatigue crack growth rate or life of P/M Rene95 alloy including the inclusions can be evaluated on the basis of the measurable surface crack length parameter. In addition, the effect of two inclusions on the fatigue crack initiation behavior was investigated by the in-situ observation with SEM. 相似文献
103.
孙克成 《河南机电高等专科学校学报》2006,14(6):124-126
竞赛过程中运动员的生理变化、心理变化以及运动行为变化为诊断情绪提供了线索。文中根据情绪的性质和不同专项对情绪唤醒水平的不同要求,介绍了供教练员参考使用的诊断运动员情绪状态的“观察询问法”和供运动员参考使用的“自我观察体验法”。这种诊断方法简便、实用、快捷,易于掌握,便于推广,教练员、运动员易于接受。 相似文献
104.
Pest oxidation has been known for a long time in refractory transition-metal disilicides such as NbSi2 and MoSi2[1―4]. However, the origin of pesting reaction of these materials is still under debate. Although the pesting phenomenon in NbSi2 has been reported in several works[5―7], a direct study of the mechanism is scarce at the moment. Compared to NbSi2, pesting in MoSi2 has received relatively extensive attention. Mckamey et al.[8] showed fragmentation near 773K occurred easily in as… 相似文献
105.
A special experiment setup was designed to observe the interaction between bubbles and particle in flotation cell and to analyze the bubble characteristics such as bubble size, distribution and bubble-loading efficiency. Bubbles in water-gas system and three-phase system were measured. The results indicate that with the current setup the bubbles as small as 10μm can be easily distinguished. The average size of the bubbles generated under the given conditions in two-phase system is 410μm at frother concentration of 0. 004%, which is in good correspondence with the results of other works. The effect of frother on bubble size was probed. Increasing frother concentration from 0 to 0. 004% causes a reduction of bubble size from 700 to 400μm. The bubble loading efficiency was reported. The result indicates that the fine particle is more easily entrapped than the coarse particle. Some factors, which have effect on measurement accuracy were discussed. The aeration speed has a significant effect on the accuracy of results, if it surpasses 30 mL/s, and the image becomes unclear due to the entrapment of fine particle. Another factor, which can affect observing results, is the sampling position. At a wrong sampling position, the images become unclear. 相似文献
106.
Controversies are rampant in contemporary psychology concerning the appropriate method for observing consciousness and the role inner experience should play in psychological theorizing. These conflicting orientations reflect, in part, methodological differences between natural science and human science interpretations of psychology. Humanistic psychology and philosophical phenomenology both employ a human science approach to psychology that seeks to explain behavior in terms of a person's subjective existence. Maslow's and Heidegger's formulations are both fulfillment theories in that they specify moral values that suggest how life ought to be lived. Natural science methodology rejects the possibility that moral imperatives can be validated, whereas human science methodology allows phenomenological convictions to justify recommendations about a fulfilled life and a good society. The social role of psychology is analyzed within the framework of phenomenological convictions and scientific truth. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
M. Dolores Jiménez-Gamero Juan Luis Moreno-Rebollo Juan M. Muñoz-Pichardo Ana M. Muñoz-Reyes 《TEST》2005,14(2):515-542
One of the areas of Statistics in which the influence analysis has been widely studied is the multiple linear regression model.
Nevertheless, the influence diagnostics proposed in this context cannot be applied to regression in complex survey, under
randomized inference, since the i.i.d. case does not incorporate any probability weighting or population structure, such as
clustering, stratification or measures of size into the analysis.
In this paper we introduce some influence diagnostics in regression in complex survey. They are built on the conditional bias
concept (Moreno-Rebollo et al., 1999). We emphasize the similarities and differences of the proposed measures with respect
to the existing ones for the i.i.d. case.
Research partly supported by the Spanish MCYT grant BFM2001-3844 and Spanish MEC grant MTM2004-0111433. 相似文献
108.
基于矢量观测确定飞行器姿态的算法综述 总被引:15,自引:1,他引:15
随着无陀螺飞行器的出现,关于矢量定姿算法的研究已引起重视。这方面的理论基础比较薄弱,有待解决的问题还很多,为给今后的研究工作提供有用的参考,按照确定性算法与状态估计法的分类原则,介绍近几十年来国外研究者在矢量定姿算法研究方面所取得的主要研究成果,阐述典型算法的基本思想及其发展状况,并进行比较分析。结合航天科技发展现状及趋势,特别指出了无陀螺矢量定姿法研究的重要现实意义:不仅为促进小型(无陀螺)飞行器的发展奠定了理论基础,而且为延长载有陀螺飞行器的寿命提供一个新的解决思路。 相似文献
109.
为了进一步了解烟酰胺配体的配位特征和结构特点,对配合物Mn(Nica)2Cl2,Fe(Nica)2Cl2,Co(Nica)2Cl2,Ni(Nica)2Cl2,Cu(Nica)2Cl2和Zn(Nica)2Cl2进行了合成和红外光谱、透射电镜、扫描电镜的表征,烟酰胺以吡啶氮与金属离子配位,Mn(Ⅱ),Fe(Ⅱ),Co(Ⅱ),Ni(Ⅱ)配合物为六方晶体结构,Cu(Ⅱ)配合物为金刚石立方晶体结构。 相似文献
110.
针对“矢量观测+陀螺”这种典型的三轴稳定卫星姿态确定系统配置模式,采用欧拉角作为姿态参数,应用扩展卡尔曼滤波技术综合处理姿态测量信息,给出了具有良好滤波性能的轨道姿态估计算法.在算法的设计过程中,针对单矢量观测情况,通过改进协方差修正算法加快了状态估值的收敛速度;针对多矢量观测情况,把 QUEST 法作为矢量观测数据压缩技术有效地结合进姿态估计器中,使得在多矢量观测情况下的滤波修正算法得到了简化. 相似文献