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41.
Recovery of the unknown parameter in an abstract inverse estimation model can be based on regularizing the inverse of the operator defining the model. Such regularized-inverse type estimators are constructed with the help of a version of the spectral theorem due to Halmos, after suitable preconditioning. A lower bound to the minimax risk is obtained exploiting the van Trees inequality. The proposed estimators are shown to be asymptotically optimal in the sense that their risk converges to zero, as the sample size tends to infinity, at the same rate as this lower bound. The general theory is applied to deconvolution on locally compact Abelian groups, including both indirect density and indirect regression function estimation.  相似文献   
42.
Annals of Operations Research - The sport teams grouping problem (STGP) concerns the assignment of sport teams to round-robin tournaments. The objective is to minimize the total travel distance of...  相似文献   
43.
We consider a latency problem with a profit pi for each client. When serving a client, a revenue of pit is collected. The goal is to find routes for the servers such that total collected revenue is maximized. We study the complexity of different variants of this problem on the line.  相似文献   
44.
We give a proof of the irrationality of p-adic zeta-values ξp(κ) for p = 2, 3 and κ = 2,3.Such results were recently obtained by Calegari as an application of overconvergent p-adic modular forms. In this paper we present an approach using classical continued fractions discovered by Stieltjes. In addition we show the irrationality of some other p-adic L-series values, and values of the p-adic Hurwitz zeta-function.  相似文献   
45.
An interval arithmetic based branch-and-bound optimizer is applied to find the singular points and bifurcations in studying feasibility of batch extractive distillation. This kind of study is an important step in synthesizing economic industrial processes applied to separate liquid mixtures of azeotrope-forming chemical components. The feasibility check methodology includes computation and analysis of phase plots of differential algebraic equation systems (DAEs). Singular points and bifurcations play an essential role in judging feasibility. The feasible domain of parameters can be estimated by tracing the paths of the singular points in the phase plane; bifurcations indicate the border of this domain. Since the algebraic part of the DAE cannot be transformed to an explicit form, implicit function theorem is applied in formulating the criterion of bifurcation points. The singular points of the maps at specified process parameters are found with interval methodology. Limiting values of the parameters are determined by searching for points satisfying bifurcation criteria.  相似文献   
46.
We discuss a new resource paradox in the area of scheduling: Increasing the speed of some machines in a no-wait flow-shop instance may actually worsen the optimal makespan. We construct instances for which the ratio between optimal makespan with improved speed and optimal makespan without improved speed becomes arbitrarily bad.  相似文献   
47.
The multi-index assignment problem (MIAP) with decomposable costs is a natural generalization of the well-known assignment problem. Applications of the MIAP arise, for instance, in the field of multi-target multi-sensor tracking. We describe an (exponentially sized) neighbourhood for a solution of the MIAP with decomposable costs, and show that one can find a best solution in this neighbourhood in polynomial time. Based on this neighbourhood, we propose a local search algorithm. We empirically test the performance of published constructive heuristics and the local search algorithm on random instances; a straightforward iterated local search algorithm is also tested. Finally, we compute lower bounds to our problem, which enable us to assess the quality of the solutions found.  相似文献   
48.

Background  

The 5-HT3 receptor is a member of a neurotransmitter-gated ion channel family which includes nicotinic acetylcholine, GABAA, and glycine receptors. While antibodies specific for the 5-HT3A receptor subunit are plentiful, and have revealed a wealth of structural and functional information, few antisera exist for the detection of 5-HT3B receptor subunits. Here we describe the generation and characterisation of a rabbit polyclonal antiserum that specifically recognises 5-HT3B receptor subunits  相似文献   
49.
The reactivity of the 2,2′-, 2,4′-, 4,4′-dibenzyldiisocyanate (2,2′-, 2,4′-, 4,4′-DBDI) with n-butanol in benzene has been studied. The concentrations of all species were monitored by using high performance liquid chromatography (HPLC). The reactivity of 4,4′-DBDI is similar to that of 4,4′-diphenylmethanediisocyanate (4,4′-MDI). Very strong intramolecular catalytic effects were noticed in the case of 2,2′-DBDI, probably due to the variable molecular geometry. These effects are responsible for the whole reaction pattern. The 2,4′-DBDI NCO ortho and para groups reactivities are different and comparable to that of 2,4-toluylenediisocyanate (2,4-TDI).  相似文献   
50.
In this note we characterize regular perturbations of finite state Markov chains in terms of continuity properties of its fundamental matrix. A perturbation turns out to be regular if and only if the fundamental matrix can be approximated by the discounted deviation from stationarity for small perturbation parameters. We also give bounds to asses the quality of the approximation.  相似文献   
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