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991.
Asymptotic constraint qualifications and global error bounds for convex inequalities 总被引:2,自引:0,他引:2
Received October 26, 1996 / Revised version received October 1, 1997 Published online October 9, 1998 相似文献
992.
Variable responses are fundamental for all experiments, and they can consist of information-rich, redundant, and low signal intensities. A dataset can consist of a collection of variable responses over multiple classes or groups. Usually some of the variables are removed in a dataset that contain very little information. Sometimes all the variables are used in the data analysis phase. It is common practice to discriminate between two distributions of data; however, there is no formal algorithm to arrive at a degree of separation (DS) between two distributions of data. The DS is defined herein as the average of the sum of the areas from the probability density functions (PDFs) of A and B that contain a ≥ percentage of A and/or B. Thus, DS90 is the average of the sum of the PDF areas of A and B that contain ≥90% of A and/or B. To arrive at a DS value, two synthesized PDFs or very large experimental datasets are required. Experimentally it is common practice to generate relatively small datasets. Therefore, the challenge was to find a statistical parameter that can be used on small datasets to estimate and highly correlate with the DS90 parameter. Established statistical methods include the overlap area of the two data distribution profiles, Welch’s t-test, Kolmogorov–Smirnov (K–S) test, Mann–Whitney–Wilcoxon test, and the area under the receiver operating characteristics (ROC) curve (AUC). The area between the ROC curve and diagonal (ACD) and the length of the ROC curve (LROC) are introduced. The established, ACD, and LROC methods were correlated to the DS90 when applied on many pairs of synthesized PDFs. The LROC method provided the best linear correlation with, and estimation of, the DS90. The estimated DS90 from the LROC (DS90–LROC) is applied to a database, as an example, of three Italian wines consisting of thirteen variable responses for variable ranking consideration. An important highlight of the DS90–LROC method is utilizing the LROC curve methodology to test all variables one-at-a-time with all pairs of classes in a dataset. 相似文献
993.
In this paper we address the problem of cooperation and collision avoidance for Lagrangian systems with input disturbances. We design control laws that guarantee cooperation as well as collision-free maneuvers. We show, using a two-step proof, that the avoidance part of the control laws guarantees safety of the agents independently of the coordinating part. Then, we establish an ultimate bound on the region to which all the agents converge to. The obtained theoretical results are illustrated through numerical examples. 相似文献
994.
995.
The characteristic finite difference fractional steps methods for compressible two-phase displacement problem 总被引:3,自引:0,他引:3
Yirang Yuan 《中国科学A辑(英文版)》1999,42(1):48-57
For compressible two-phase displacement problem, a kind of characteristic finite difference fractional steps schemes is put
forward and thick and thin grids are used to form a complete set. Some techniques, such as piecewise biquadratic interpolation,
of calculus of variations, multiplicative commutation rule of difference operators, decomposition of high order difference
operators and prior estimates are adopted. Optimal order estimates inL
2 norm are derived to determine the error in the approximate solution.
Project supported by the National Scaling Program, the National Tackling Key Problems Program and the Doctorate Foundation
of the State Education Commission of China. 相似文献
996.
I. A. Gundyrev 《Russian Mathematics (Iz VUZ)》2008,52(4):24-37
In this article, we generalize partially the theorem of V. N. Berestovskii on characterization of similarity homogeneous (nonhomogeneous) Riemannian manifolds, i.e., Riemannian manifolds admitting transitive group of metric similarities other than motions to the case of locally compact similarity homogeneous (nonhomogeneous) spaces with intrinsic metric satisfying the additional assumption that the canonically conformally equivalent homogeneous space is δ-homogeneous or a space of curvature bounded below in the sense of A. D. Aleksandrov. Under the same assumptions, we prove the conjecture of V. N. Berestovskii on topological structure of such spaces. 相似文献
997.
具有变系数的二阶中立型差分方程 总被引:1,自引:0,他引:1
研究一类具有变系数的二阶中立型时滞差分方程
△τ^2[x(t)-c(t)x(t-τ)]=p(t)x(t-σ),t≥t0〉0
的解的振动性,给出了该类方程一切有界解振动的几个充分条件. 相似文献
998.
Wei Guo Futang Li Zuyin Zhang 《International Journal of Infrared and Millimeter Waves》1999,20(6):1129-1135
This paper describes structure of imaging system, imaging mechanism of microwave radiometer, and the microwave radiation image features and recognition. Results of image experiments show: on microwave radiation image, the features of metal target, water surface and road among trees, grassland and jungle become extremely obvious. 相似文献
999.
1000.
Hiroyuki Ito 《Mathematische Nachrichten》2010,283(7):1037-1053
In this paper, we study the Mordell‐Weil lattices of the family of elliptic surfaces which is arising from the E84 singularity, one of the ADE singularities in characteristic 2. And we construct a subfamily of the universal family of supersingular K 3 surfaces in characteristic 2 as an application (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献