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991.
992.
《复变函数与椭圆型方程》2012,57(4):285-301
Let U be the open unit disc of the complex plane. We explicitly construct the best pointwise approximation for determining a function in the Hardy space H p (U) from measured data at a countable set of points in U whenever the data is exact. A regularization scheme is given to deal with the case of nonexact data. Moreover, optimal error estimates are also studied. 相似文献
993.
Muriel De Bock Marie-Alice Meuwis Tran Quang Minh Jean-Paul Chapelle Michel Malaise Marianne Fillet 《Talanta》2010,82(1):245-594
In most diseases, the clinical need for serum/plasma markers has never been so crucial, not only for diagnosis, but also for the selection of the most efficient therapies, as well as exclusion of ineffective or toxic treatment. Due to the high sample complexity, prefractionation is essential for exploring the deep proteome and finding specific markers.In this study, three different sample preparation methods (i.e., highly abundant protein precipitation, restricted access materials (RAM) combined with IMAC chromatography and peptide ligand affinity beads) were investigated in order to select the best fractionation step for further differential proteomic experiments focusing on the LMW proteome (MW inferior to 40,000 Da). Indeed, the aim was not to cover the entire plasma/serum proteome, but to enrich potentially interesting tissue leakage proteins. These three methods were evaluated on their reproducibility, on the SELDI-TOF-MS peptide/protein peaks generated after fractionation and on the information supplied.The studied methods appeared to give complementary information and presented good reproducibility (below 20%). Peptide ligand affinity beads were found to provide efficient depletion of HMW proteins and peak enrichment in protein/peptide profiles. 相似文献
994.
Lutz Angermann 《Numerische Mathematik》2000,85(2):175-195
Summary. The proposed method is based on an additive decomposition of the differential operator and the subsequent fitted discretization
of the resulting components. For standard situations, the derived stability and error estimates in the energy norm qualitatively
coincide with well-known estimates. In the case of small diffusion, a uniform error estimate with reduced order is obtained.
Received August 7, 1997 / Revised version received July 15, 1998 / Published online December 6, 1999 相似文献
995.
996.
Robert Aehle 《manuscripta mathematica》2000,102(2):169-176
We develop a method to refine a given degeneration of modules. This enables us to give a new proof of the equivalence of
the partial orders ≤deg and ≤ext in the case that the algebra Λ has a directed Auslander–Reiten quiver.
Received: 11 November 1999 相似文献
997.
L. Baratchart V. A. Prokhorov E. B. Saff 《Foundations of Computational Mathematics》2001,1(4):385-416
Let E \subset(-1,1) be a compact set, let μ be a positive Borel measure with support \supp μ =E , and let H
p
(G),
1≤ p ≤∈fty, be the Hardy space of analytic functions on the open unit disk G with circumference Γ={z \colon |z|=1} . Let Δ
n,p
be the error in best approximation of the Markov function \frac{1}{2π i} ∈t_E \frac{d μ(x)}{z-x} in the space L
p
(Γ) by meromorphic functions that can be represented in the form h=P/Q , where P ∈ H
p
(G),
Q is a polynomial of degree at most n , Q\not \equiv 0 . We investigate the rate of decrease of Δ
n,p
,
1≤ p ≤∈fty , and its connection with n -widths. The convergence of the best meromorphic approximants and the limiting distribution of poles of the best approximants
are described in the case when 1<p≤∈fty and the measure μ with support E=[a,b] satisfies the Szegő condition ∈t_a^b \frac{\log(d μ/ d x)}{\sqrt{(x-a)(b-x)}} dx >- ∈fty.
July 27, 2000. Final version received: May 19, 2001. 相似文献
998.
This paper treats the problem of estimating the restricted means of normal distributions with a known variance, where the means are restricted to a polyhedral convex cone which includes various restrictions such as positive orthant, simple order, tree order and umbrella order restrictions. In the context of the simultaneous estimation of the restricted means, it is of great interest to investigate decision-theoretic properties of the generalized Bayes estimator against the uniform prior distribution over the polyhedral convex cone. In this paper, the generalized Bayes estimator is shown to be minimax. It is also proved that it is admissible in the one- or two-dimensional case, but is improved on by a shrinkage estimator in the three- or more-dimensional case. This means that the so-called Stein phenomenon on the minimax generalized Bayes estimator can be extended to the case where the means are restricted to the polyhedral convex cone. The risk behaviors of the estimators are investigated through Monte Carlo simulation, and it is revealed that the shrinkage estimator has a substantial risk reduction. 相似文献
999.
1000.
B. Bousquet L. Canioni J. Plantard L. Sarger 《Applied physics. B, Lasers and optics》1999,68(4):689-692
Received: 8 July 1998 / Revised version: 29 October 1998 / Published online: 24 February 1999 相似文献