排序方式: 共有11条查询结果,搜索用时 8 毫秒
1.
Physics of Atomic Nuclei - A model of dynamics with separate temperature feedback formed by average temperatures of the fuel and the coolant is constructed for the IBR-2M pulsed reactor of periodic... 相似文献
2.
Panel‐based stratified cluster sampling and analysis for photovoltaic outdoor measurements 下载免费PDF全文
We study a stratified multisite cluster‐sampling panel time series approach in order to analyse and evaluate the quality and reliability of produced items, motivated by the problem to sample and analyse multisite outdoor measurements from photovoltaic systems. The specific stratified sampling in spatial clusters reduces sampling costs and allows for heterogeneity as well as for the analysis of spatial correlations due to defects and damages that tend to occur in clusters. The analysis is based on weighted least squares using data‐dependent weights. We show that this does not affect consistency and asymptotic normality of the least squares estimator under the proposed sampling design under general conditions. The estimation of the relevant variance–covariance matrices is discussed in detail for various models including nested designs and random effects. The strata corresponding to damages or manufacturers are modelled via a quality feature by means of a threshold approach. The analysis of outdoor electroluminescence images shows that spatial correlations and local clusters may arise in such photovoltaic data. Further, relevant statistics such as the mean pixel intensity cannot be assumed to follow a Gaussian law. We investigate the proposed inferential tools in detail by simulations in order to assess the influence of spatial cluster correlations and serial correlations on the test's size and power. ©2016 The Authors. Applied Stochastic Models in Business and Industry published by John Wiley & Sons, Ltd. 相似文献
3.
Pepelyshev Yu. N. Rogov A. D. Sidorkin S. F. 《Physics of Particles and Nuclei Letters》2019,16(6):933-951
Physics of Particles and Nuclei Letters - The neutron source operating at the Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research (JINR, Dubna, Russia), based on an IBR-2M... 相似文献
4.
Holger Dette Viatcheslav B. Melas Andrey Pepelyshev 《Annals of the Institute of Statistical Mathematics》2011,63(5):981-1003
In the common nonparametric regression model we consider the problem of constructing optimal designs, if the unknown curve
is estimated by a smoothing spline. A special basis for the space of natural splines is introduced and the local minimax property
for these splines is used to derive two optimality criteria for the construction of optimal designs. The first criterion determines
the design for a most precise estimation of the coefficients in the spline representation and corresponds to D-optimality, while the second criterion is the G-optimality criterion and corresponds to an accurate prediction of the curve. Several properties of the optimal designs are
derived. In general, D- and G-optimal designs are not equivalent. Optimal designs are determined numerically and compared with the uniform design. 相似文献
5.
The article considers the neutronics aspect of the IBR-2 reactor optimization: whether it is possible in theory to create an IBR-2-type reactor with a neutron flux in beams above the existing 0.5 × 1013 n/(cm2 s). The calculations have shown that the thermal neutron flux theoretically can be increased to (2.0−2.5) × 1013 n/(cm2 s), but only with a complete change in the reactor design: reducing the core volume, replacing the fuel type with a denser one, and changing the beam extraction system from radial to tangential. The technical implementation of these requirements is currently a challenge. 相似文献
6.
Vinogradov A. V. Pepelyshev Yu. N. Rogov A. D. Sidorkin S. F. 《Physics of Particles and Nuclei Letters》2019,16(6):952-966
Physics of Particles and Nuclei Letters - Parameters of the optimum alternative of a high-flux pulsed neutron source (fourth-generation neutron source in Dubna), which is foreseen to replace the... 相似文献
7.
Livio Corain Viatcheslav B. Melas Andrey Pepelyshev Luigi Salmaso 《Advances in Data Analysis and Classification》2014,8(3):339-356
The permutation approach for testing the equality of distributions and thereby comparing two populations of functional data has recently received increasing attention thanks to the flexibility of permutation tests to handle complex testing problems. The purpose of this work is to present some new insights in the context of nonparametric inference on functional data using the permutation approach, more specifically we formally show the equivalence of some permutation procedures proposed in the literature and we suggest the use of the permutation and combination-based approach within the basis function approximation layout. Validation of theoretical results is shown by simulation studies. 相似文献
8.
Holger Dette Viatcheslav B. Melas Andrey Pepelyshev 《Annals of the Institute of Statistical Mathematics》2002,54(4):945-959
In the common trigonometric regression model we investigate the D-optimal design problem, where the design space is a partial circle. It is demonstrated that the structure of the optimal design depends only on the length of the design space and that the support points (and weights) are analytic functions of this parameter. By means of a Taylor expansion we provide a recursive algorithm such that the D-optimal designs for Fourier regression models on a partial circle can be determined in all cases. In the linear and quadratic case the D-optimal design can be determined explicitly. 相似文献
9.
Andrey Pepelyshev Anatoly Zhigljavsky Antanas Žilinskas 《Journal of Global Optimization》2018,71(1):57-71
We investigate the rate of convergence of general global random search (GRS) algorithms. We show that if the dimension of the feasible domain is large then it is impossible to give any guarantee that the global minimizer is found by a general GRS algorithm with reasonable accuracy. We then study precision of statistical estimates of the global minimum in the case of large dimensions. We show that these estimates also suffer the curse of dimensionality. Finally, we demonstrate that the use of quasi-random points in place of the random ones does not give any visible advantage in large dimensions. 相似文献
10.
Physics of Atomic Nuclei - It is shown on the basis of experimental and model studies at the IBR-2 and IBR-2M reactors that pulsed reactors of periodic operation (PRPO) have fundamental limitations... 相似文献