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81.
徐进军 《武汉大学学报(信息科学版)》1997,(4)
综合分析和比较了自回归模型和回归模型的特点,提出了采用线性综合模型来预报崩滑体变形的思想,以弥补自回归模型或回归模型预报的不足。实测资料的处理结果表明,综合线性模型具有特别的适用性。 相似文献
82.
本文考虑液固耦联及底板几何非线性与土壤弹性,建立了液-固-土耦合的储液罐翘离分析力学模型。算例表明,恢复力矩与翘离角之间的关系可以表达为分段线性,翘离将使地震响应增大。 相似文献
83.
84.
影响上海市地价空间分布的区位因子分析 总被引:28,自引:5,他引:28
本文采用GIS技术和多元线性回归分析方法,以土地批租地块为样本,分析上海市地价与城市区位因子的线性关系。回归分析结果表明;南京路,市中心和淮海路是影响上海市寺价空间差异的主要区位因子,外滩,次级商业中心和交通结节点对地价的影响很小,表明上海市地价的空间分布具有很高的向心性。 相似文献
85.
线性地质统计学的发展与地质工作逐渐由定性向定量、由人工劳动逐渐被计算机取代的过程密切相关的。对样品品位赋予一定的权值进行滑动加权平均,来估计中心块段平均品位的方法,使地质问题的计算能在计算机上实现开辟了新的途径。 相似文献
86.
Peter K. Kitanidis 《Mathematical Geology》1997,29(3):335-348
This article discusses the issue of whether to use a variable mean and describes a test that can be used to evaluate whether
it is justified to add terms to the drift (deterministic part) of a geostatistical model. The basic model could be the intrinsic
one, where the deterministic part is a constant, and the alternate model could be any model that includes a constant term
in the expression for the drift. Also, differences between constant- and variable-mean models are discussed. 相似文献
87.
Y. -K. Tung K. -C. Yeh J. -C. Yang 《Stochastic Environmental Research and Risk Assessment (SERRA)》1997,11(2):145-171
Hydrologic regionalization is a useful tool that allows for the transfer of hydrological information from gaged sites to ungaged
sites. This study developed regional regression equations that relate the two parameters in Nash's IUH model to the basin
characteristics for 42 major watersheds in Taiwan. In the process of developing the regional equations, different regression
procedures including the conventional univariate regression, multivariate regression, and seemingly unrelated regression were
used. Multivariate regression and seeming unrelated regression were applied because there exists a rather strong correlation
between the Nash's IUH parameters. Furthermore, a validation study was conducted to examine the predictability of regional
equations derived by different regression procedures. The study indicates that hydrologic regionalization involving several
dependent variables should consider their correlations in the process of establishing the regional equations. The consideration
of such correlation will enhance the predictability of resulting regional equations as compared with the ones from the conventional
univariate regression procedure. 相似文献
88.
The separation of the influence of nutrients and climate on the varve time-series of baldeggersee, Switzerland 总被引:7,自引:2,他引:7
The varve data-set from a freeze-core taken in the deepest part of Baldeggersee was subjected to different multivariate statistical
analyses in order to estimate the amount of variance in the varve thickness measures explicable by past climate and by the
trophic state of the lake. A comparison of two different time-periods (1902 to1992 versus 1920 to 1980) revealed that the
lake restoration programme since 1982 has had a significant impact on the formation of the seasonal layers. Results of the
partitioning of the variance in the varve thickness measures showed that about two thirds of the variance are unexplained
by a climate and trophic state model and that trophic state explains 6%, whereas climate accounts for about 28% of the variance
before the effect of lake restoration had a strong impact on the varves. Among the climate parameters the amount of annual
precipitation is a strong predictor for explaining the thickness of both dark layer and total couplet thickness, whereas summer
precipitation is important for the thickness of the light layer. 相似文献
89.
K. -C. Yeh J. -C. Yang Y. -K. Tung 《Stochastic Environmental Research and Risk Assessment (SERRA)》1997,11(2):173-192
Hydrologic model parameters obtained from regional regression equations are subject to uncertainty. Consequently, hydrologic
model outputs based on the stochastic parameters are random. This paper presents a systematic analysis of uncertainty associated
with the two parameters, N and K, in Nash's IUH model from different regional regression equations. The uncertainty features
associated with N and K are further incorporated to assess the uncertainty of the resulting IUH. Numerical results indicate
that uncertainty of N and K from the regional regression equations are too significant to be ignored. 相似文献
90.
Hydrologic model parameters obtained from regional regression equations are subject to uncertainty. Consequently, hydrologic
model outputs based on the stochastic parameters are random. This paper presents a systematic analysis of uncertainty associated
with the two parameters, N and K, in Nash's IUH model from different regional regression equations. The uncertainty features
associated with N and K are further incorporated to assess the uncertainty of the resulting IUH. Numerical results indicate
that uncertainty of N and K from the regional regression equations are too significant to be ignored. 相似文献