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31.
建筑感性工学是建筑美学与建筑工学相结合的产物。建筑设计在感觉参数、知觉意象与听觉系统等感性工学维度上具有独特的美学理念。从建筑形象设计考量,感觉参数是建筑感性工学的首要维度;在建筑空间设计向度上,知觉意象是建筑感性工学的体验形态;在建筑时间设计中,听觉系统是建筑感性工学的立体声响诉求。在当代感性工学与商业资本运作下,建筑感性工学显示出建筑空间既是居住者生活情趣的视听空间,也是社会的表情、文化与身份的独特价值空间。  相似文献   
32.
Conditions for choosing between restricted and unrestrieted maximum likelihood estimators based on various asymptotic risk oriteria are derived. These conditions involve the non-centrality parameters of classical and specification test statistics, and are generlizations of well known results for the linear regression model.  相似文献   
33.
The problem of calculating approximate confidence limits for the difference between success probability parameters of two Pólya distributions is solved for the first time. We suggest some new methods for determining these approximate confidence limits and consider their application to special cases: namely for the binomial and hypergeometric distributions. The various approximate confidence limits are evaluated and compared.  相似文献   
34.
The usual F-test of the analysis of variance is reconsidered within the Bayesian framework, In terms of predictive distributions, This leads to the notion of semi-Bayesian significance test, so called because it consists in only probabilizing the space of nuisance parameters, thus bringing a general principle for “eliminating” nuisance parameters, or more exactly incorporating information about these parameters. The approach is shown to extend the F-tests, by allowing the testing of hypotheses of non-zero effects.  相似文献   
35.
用一种新的思路和方法 ,先计算低通、再计算高通滤波器的有关参数 ,然后组合成带通滤波器  相似文献   
36.
Measuring a statistical model's complexity is important for model criticism and comparison. However, it is unclear how to do this for hierarchical models due to uncertainty about how to count the random effects. The authors develop a complexity measure for generalized linear hierarchical models based on linear model theory. They demonstrate the new measure for binomial and Poisson observables modeled using various hierarchical structures, including a longitudinal model and an areal‐data model having both spatial clustering and pure heterogeneity random effects. They compare their new measure to a Bayesian index of model complexity, the effective number pD of parameters (Spiegelhalter, Best, Carlin & van der Linde 2002); the comparisons are made in the binomial and Poisson cases via simulation and two real data examples. The two measures are usually close, but differ markedly in some instances where pD is arguably inappropriate. Finally, the authors show how the new measure can be used to approach the difficult task of specifying prior distributions for variance components, and in the process cast further doubt on the commonly‐used vague inverse gamma prior.  相似文献   
37.
提出了一种时变参数混沌同步保密通信方法,极大地提高了混沌同步的通信保密性,使目前的各种破译手段均无法破译该方法;并基于Chua电路进行了仿真。采用该方法进行混沌同步通信,击败了目前各种破译手段的攻击,证实了其高保密性。  相似文献   
38.
针对传统送钻方式的不足及钻井过程复杂、数学模型难建立等特点,在简要分析交流变频自动送钻系统的工作原理和影响送钻的各因素之间关系后,提出将参数自调整模糊控制与交流变频恒钻压自动送钻相结合。通过对钻压趋势的判断,采用参数自调整模糊PI 控制,实现对送钻电机转速的控制。该算法不需要精确的数学模型,可通过自学习实时修正控制参数。试验表明:控制效果良好,在保证恒钻压的基础上,可实现稳速送钻,提高了系统调节的快速性、自适应性和鲁棒性,精度高,现场应用证实此算法控制效果优越,可实现送钻稳态精度在±0.5 t 之内,而且送钻更加平稳,控制算法亦具有通用性。  相似文献   
39.
Abstract.  We propose an easy to implement method for making small sample parametric inference about the root of an estimating equation expressible as a quadratic form in normal random variables. It is based on saddlepoint approximations to the distribution of the estimating equation whose unique root is a parameter's maximum likelihood estimator (MLE), while substituting conditional MLEs for the remaining (nuisance) parameters. Monotoncity of the estimating equation in its parameter argument enables us to relate these approximations to those for the estimator of interest. The proposed method is equivalent to a parametric bootstrap percentile approach where Monte Carlo simulation is replaced by saddlepoint approximation. It finds applications in many areas of statistics including, nonlinear regression, time series analysis, inference on ratios of regression parameters in linear models and calibration. We demonstrate the method in the context of some classical examples from nonlinear regression models and ratios of regression parameter problems. Simulation results for these show that the proposed method, apart from being generally easier to implement, yields confidence intervals with lengths and coverage probabilities that compare favourably with those obtained from several competing methods proposed in the literature over the past half-century.  相似文献   
40.
In comparing several regressions E(yij) =αi + βixij i = 1, 2, ..., k, j = 1,2, ..., ni, researchers are generally interested in the following five problems: whether they have (1) equal slope, (2) equal intercept, (3) coincidence, (4) common intersection on X-axis, and (5) common intersection on (X,Y) - plane. Problems (1) - (3) can be put into the framework of the general linear hypothesis and the F-test can be used. However, problems (4) and (5) cannot be put into the general linear hypothesis because they are ratios of parameters. Hence, in this paper we consider the generalized likelihood ratio test for hypothesis testing. An application to an enzyme kinetics problem in Aniline Metabolism is demonstrated  相似文献   
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