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991.
 It is well known that erroneous data reported to a physician may strongly affect medical decision making. For routine clinical chemistry purposes, different instrumentation can be used to compare measurements of unknown samples with standard reference materials. Currently, acceptable limits of accuracy and precision are poorly defined in the field of clinical chemistry laboratories. In this article, problems associated with spectrophotometric measurements, both manual and automated, are discussed. The task of the validation of photometric systems for clinical analyses is currently of considerable interest. Some practical aspects of this validation and the use of reference materials for this activity in the national area are discussed. Received: 7 November 1996 Accepted: 14 January 1997  相似文献   
992.
Optical techniques that measure displacements play a very important role in current experimental mechanics, material sciences and metrology. This paper presents a survey of developments in these techniques from a personal experience point of view. Three main aspects are considered. Mathematical and numerical models used in the interpretation of fringe information and the corresponding data processing techniques. Optical and electro-optical developments that have taken place to improve the sensitivity, and the efficiency of these methods to make them competitive with purely numerical methods. Applications that have arisen from the synergy between advanced computational capabilities and optics are also presented.  相似文献   
993.
"边信息"的效用优化及其影响   总被引:1,自引:0,他引:1  
本文考虑受随机因素影响的股票价模型 ,投资者仅知道的股价信息 (公共信息 )和“边信息”的效用优化问题 .我们利用测度的变换和投影 ,给出了具有“边信息”和不具“边信息”两种情况下的最优财富形式 .对于对数效用函数 ,我们比较最优效用 ,讨论了“边信息”的影响  相似文献   
994.
Various questions about the invariant measures of a dynamical system can be answered by computations of regular functionals or by ranking methods based on a set of observations. This includes symmetry tests and the determination of dimension coefficients. The paper contains the theoretical results and several simulations explain the methods.  相似文献   
995.
On the value distribution of the Matsumoto zeta-function   总被引:1,自引:0,他引:1  
The Matsumoto zeta-function is defined by a polynomial Euler product and is a generalization of classical zeta-functions. In the paper a discrete limit theorem in the sense of the weak convergence of probability measures on the complex plane for the Matsumoto zeta-function is proved.  相似文献   
996.
A Superprocess with coalescing spatial motion is constructed in terms of one-dimensional excursions. Based on this construction, it is proved that the superprocess is purely atomic and arises as scaling limit of a special form of the superprocess with dependent spatial motion studied in Dawson et al. (Refs. 5, 19–20).  相似文献   
997.
Stochastic geometry models based on a stationary Poisson point process of compact subsets of the Euclidean space are examined. Random measures on ?d, derived from these processes using Hausdorff and projection measures are studied. The central limit theorem is formulated in a way which enables comparison of the various estimators of the intensity of the produced random measures. Approximate confidence intervals for the intensity are constructed. Their use is demonstrated in an example of length intensity estimation for the segment processes. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
998.
999.
Let be an infinitely divisible probability measure onR n without Gaussian component and let be its Lévy measure. Suppose that is absolutely continuous with respect to the Lebesgue measure . We investigate the structure of the set n of admissible translates of . This yields a unified presentation of previously known results. We also show that if(S)>0 then is equivalent to , under the assumption that supp =R n , whereS is the closure of the semigroup generated by the support of .The research of this author is supported by KBN Grant.The research of this author is supported by AFSOR Grant No. 90-0168, and the University of Tennessee Science Alliance, a State of Tennessee Center of Excellence.  相似文献   
1000.
We show by an example that small perturbations with respect to the convergence in measure of the coefficients A and B may affect the complete controllability of the linear control system , where x is the state and u is the control. This answers a question raised in Ref. 1.  相似文献   
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