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981.
982.
本文首先研究了n阶Lotka Volterra系统的非负平衡点之间的关系 .然后在此基础上研究了该系统的永久持续生存问题 ,得到了若干判别n阶Lotka Volterra系统永久持续生存的充要条件 . 相似文献
983.
二阶矩阵微分系统振动的区间准则 总被引:2,自引:0,他引:2
本文研究了二阶矩阵微分系统的振动性:(P(t)Y')'+Q(t)Y= 0,t∈[t0,∞),其中P,Q,Y是n×n实矩阵函数,P(t),Q(t)是对称的且P(t)正定.所得的准则仅依赖于系统在[t0,∞)的一个子区间序列的信息而有别于已知的大多数结论,我们的结果更精确,并能应用于判别如极端情形. 相似文献
984.
《Analytical letters》2012,45(5):1341-1354
Abstract Twelve procedures of sample pretreatment for manganese determination in blood serum were tested in comparable instrumental conditions. the best results were obtained by dilution of serum with diluted nitric acid, which leads to formation of an internal matrix modifier composed of calcium and phosphoric acid. Other procedures may also give satisfactory results, but then as standards aqueous albumin solutions should be used. 相似文献
985.
In this paper, we determine all the Rota-Baxter operators of weight zero on semigroup algebras of order two and three with the help of computer algebra. We determine the matrices for these Rota-Baxter operators by directly solving the defining equations of the operators. We also produce a Mathematica procedure to predict and verify these solutions. 相似文献
986.
We investigate the Glauber divergences in nonfactorizable annihilation amplitudes for two-body hadronic heavy meson decays in the factorization theorem at one-loop level. These divergences can be absorbed into the Glauber factors in the dominant kinematic regions of small parton momenta, which modify the interference between a nonfactorizable annihilation amplitude and other amplitudes by rotating it with a phase. We postulate that only the Glauber effect associated with a pion is significant, due to its special role as a bound state and as a pseudo Nambu–Goldstone boson simultaneously. It is elaborated that the data of the and branching ratios have revealed prominent Glauber effects. This work provides a solid theoretical ground for the factorization-assisted topological-amplitude parametrization of two-body hadronic meson decays. 相似文献
987.
We consider the assignment of enterprise applications in virtual machines to physical servers, also known as server consolidation problem. Data center operators try to minimize the number of servers, but at the same time provide sufficient computing resources at each point in time. While historical workload data would allow for accurate workload forecasting and optimal allocation of enterprise applications to servers, the volume of data and the large number of resulting capacity constraints in a mathematical problem formulation renders this task impossible for any but small instances. We use singular value decomposition (SVD) to extract significant features from a large constraint matrix and provide a new geometric interpretation of these features, which allows for allocating large sets of applications efficiently to physical servers with this new formulation. While SVD is typically applied for purposes such as time series decomposition, noise filtering, or clustering, in this paper features are used to transform the original allocation problem into a low-dimensional integer program with only the extracted features in a much smaller constraint matrix. We evaluate the approach using workload data from a large data center and show that it leads to high solution quality, but at the same time allows for solving considerably larger problem instances than what would be possible without data reduction and model transform. The overall approach could also be applied to similar packing problems in service operations management. 相似文献
988.
Liaqat Ali Khan 《Journal of Mathematical Analysis and Applications》2008,343(1):141-150
In this paper, we consider the notion of module homomorphisms in the general topological module setting and establish their linearity and continuity under some suitable conditions. We also introduce the strict and uniform topologies on the modules of continuous linear homomorphisms and study their various properties. 相似文献
989.
Modern instruments together with the use of standard reference materials have improved the accuracy and long-term reproducibility of the analysis of nutrients (ammonium, nitrate, nitrite, phosphate and silicate) in sea water using segmented-flow analysis, so that errors arising from matrix effects become more significant. Colorimetric detectors with bubble-through flowcells have become widely used for seawater analysis in recent years and their associated matrix effects are described. A re-examination of all categories of matrix effects, whose main origin is salinity, was thus undertaken to assess how much they are liable to alter the data. Interferences were classified into four types, each of which was examined in order to show its influence on the measurements. We discuss how matrix effects can be identified, quantified, reduced and corrected. Chemistry and instrument design play a major role in some matrix effects and recommendations are given to minimise these or make them easier to correct. In particular, the correction for chemical salt effects is revisited for the general case and new, simplified procedures are proposed for its computation. A semi-automated procedure is proposed for measuring and correcting sample and refractive index blanks. 相似文献
990.