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1.
In this paper the optimal H∞, general distance problem, for continuous-time systems, with a prescribed degree on the solution is studied. The approach is based on designing the Hankel singular values using an imbedding idea. The problem is first imbedded into another problem with desirable characteristics on the Hankel singular values, then the solution to the original problem is retracted via a compression. The result is applicable to both the one-block and the four-block problems. A special case is given for illustration. 相似文献
2.
吕云霞 《昆明冶金高等专科学校学报》2004,20(2):18-20
埋在粮食筒仓中构件的受力量值的大小是筒仓结构设计中是不容忽视的问题,可作为特种结构土建结构设计人员计算参考. 相似文献
3.
4.
SQL语言中量词和空值的使用技术 总被引:1,自引:0,他引:1
丁宝康 《计算机研究与发展》1994,31(3):15-22
在SQL语言中可以引入全称量词符号FORALL,使SQL语言使用更为自然,方便。本文讨论全称量词,存在量词和ALL三种谓词之间的转换,联系和区别,以及空值存在时SQL的使用技术。 相似文献
5.
To find the exact probability distribution of the global maximum or minimum of a random field within a bounded domain is a pending problem even for Gaussian fields. Except for very special examples of fields, recourse must be taken to approximate reasoning or asymptotic considerations to be judged with respect to accuracy by simulations. In this paper, the problem is addressed through a functional equation that leads to the definition of a class of distribution functions that depend solely on process or field characteristics and domain quantities that can be calculated explicitly. This distribution function class is studied for Gaussian processes in earlier works by the author and it has been obtained explicitly for Gaussian fields on rectangular domains in the plane. Simulation studies show that rather good predictions are obtained for sufficiently smooth wide band Gaussian processes and fields. In this paper, the distribution function is obtained in general for Gaussian fields over arbitrary bounded domains with piecewise continuous and differentiable boundaries, and as in earlier works the distribution function is tested against empirical distribution functions obtained by simulation of sample functions of a smooth approximately Gaussian field, herein called a broken line Hino field. For completeness this particular field type is defined in appendix a and appendix b. The paper concludes with a statistical application on data for plain concrete tensile strength. 相似文献
6.
Tsai Jeanne L.; Miao Felicity F.; Seppala Emma; Fung Helene H.; Yeung Dannii Y. 《Canadian Metallurgical Quarterly》2007,92(6):1102
Previous studies have found that in American culture high-arousal positive states (HAP) such as excitement are valued more and low-arousal positive states (LAP) such as calm are valued less than they are in Chinese culture. What specific factors account for these differences? The authors predicted that when people and cultures aimed to influence others (i.e., assert personal needs and change others' behaviors to meet those needs), they would value HAP more and LAP less than when they aimed to adjust to others (i.e., suppress personal needs and change their own behaviors to meet others' needs). They test these predictions in 1 survey and 3 experimental studies. The findings suggest that within and across American and Chinese contexts, differences in ideal affect are due to specific interpersonal goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
This article clarifies several research issues raised in a recent article by Krieshok, Arnold, Kuperman, and Schmitz concerned with repertory grid methodology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
本文叙述了马钢引进美国FLUID DATA公司的热值仪与计算机控制系统,有效地解决了煤气混合加压生产中热值的检测与控制问题。 相似文献
9.
Krieshok Thomas S.; Arnold John J.; Kuperman Bernard D.; Schmitz Nancy K. 《Canadian Metallurgical Quarterly》1988,35(2):211
We respond to Cochran's critique of our 1986 study, which was in part a replication of Cochran's original grid methodology for the study of career values. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Farnaz Agahian Seyed Ali Amirshahi Seyed Hossein Amirshahi 《Color research and application》2008,33(5):360-371
The weighted principal component analysis technique is employed for reconstruction of reflectance spectra of surface colors from the related tristimulus values. A dynamic eigenvector subspace based on applying certain weights to reflectance data of Munsell color chips has been formed for each particular sample and the color difference value between the target, and Munsell dataset is chosen as a criterion for determination of weighting factors. Implementation of this method enables one to increase the influence of samples which are closer to target on extracted principal eigenvectors and subsequently diminish the effect of those samples which benefit from higher amount of color difference. The performance of the suggested method is evaluated in spectral reflectance reconstruction of three different collections of colored samples by the use of the first three Munsell bases. The resulting spectra show considerable improvements in terms of root mean square error between the actual and reconstructed reflectance curves as well as CIELAB color difference under illuminant A in comparison to those obtained from the standard PCA method. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 360–371, 2008 相似文献