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21.
因子分析在企业竞争力评价中的应用 总被引:22,自引:1,他引:21
根据因子分析原理,建立了企业竞争力的规模因子、效益因子和成长因子得分模型。通过现实竞争力和潜在竞争力分析,实现了企业竞争力和可持续发展的评价。 相似文献
22.
本文应用周期分析方法对江陵县棉红蜘蛛—朱砂叶螨的预测预报技术作了新的尝试.经对江陵县36年历史资料拟合,符合率高达94.4%.运用这一技术对该县1987—1996年棉红蜘蛛发生程度进行了10年长期预测预报. 相似文献
23.
本文介绍亚州第一台模拟分量电视车视频系统的设计思想,比较详细地阐述了该车的各种功能,总结了不同于复合电视车的新特点。 相似文献
24.
25.
Jochen Alber Jií Fiala 《Journal of Algorithms in Cognition, Informatics and Logic》2004,52(2):134-151
We consider the parameterized problem, whether for a given set
of n disks (of bounded radius ratio) in the Euclidean plane there exists a set of k non-intersecting disks. For this problem, we expose an algorithm running in time
that is—to our knowledge—the first algorithm with running time bounded by an exponential with a sublinear exponent. For λ-precision disk graphs of bounded radius ratio, we show that the problem is fixed parameter tractable with a running time
. The results are based on problem kernelization and a new “geometric (
-separator) theorem” which holds for all disk graphs of bounded radius ratio. The presented algorithm then performs, in a first step, a “geometric problem kernelization” and, in a second step, uses divide-and-conquer based on our new “geometric separator theorem.” 相似文献
26.
本讨论了一类广义的Lanchester模型在一些限制条件下的近似解,并给出了若干结论。 相似文献
27.
Véronique Cariou 《Computational Statistics》2006,21(2):325-341
Summary Several data can be presented as interval curves where intervals reflect a within variability. In particular, this representation
is well adapted for load profiles, which depict the electricity consumption of a class of customers. Electricity load profiling
consists in assigning a daily load curve to a customer based on their characteristics such as energy requirement. Within the
load profiling scope, this paper investigates the extension of multivariate regression trees to the case of interval dependent
(or response) variables. The tree method aims at setting up simultaneously load profiles and their assignment rules based
on independent variables. The extension of multivariate regression trees to interval responses is detailed and a global approach
is defined. It consists in a first stage of a dimension reduction of the interval response variables. Thereafter, the extension
of the tree method is applied to the first principal interval components. Outputs are the classes of the interval curves where
each class is characterized both by an interval load profile (e.g. the class prototype) and an assignment rule based on the
independent variables. 相似文献
28.
29.
30.
Near-edge X-ray absorption spectroscopy (NEXAFS) is widely used to probe the chemistry and structure of surface layers. Moreover, using ultra-high brilliance polarised synchrotron light sources, it is possible to determine the molecular alignment of ultra-thin surface films. However, the quantitative analysis of NEXAFS data is complicated by many experimental factors and, historically, the essential methods of calibration, normalisation and artefact removal are presented in the literature in a somewhat fragmented manner, thus hindering their integrated implementation as well as their further development. This paper outlines a unified, systematic approach to the collection and quantitative analysis of NEXAFS data with a particular focus upon carbon K-edge spectra. As a consequence, we show that current methods neglect several important aspects of the data analysis process, which we address with a combination of novel and adapted techniques. We discuss multiple approaches in solving the issues commonly encountered in the analysis of NEXAFS data, revealing the inherent assumptions of each approach and providing guidelines for assessing their appropriateness in a broad range of experimental situations. 相似文献