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Uncertainty Analysis of Neutron Diffusion Eigenvalue Problem Based on Reduced-order Model
Yuanzineng kexue jishu, 2023 In order to improve the efficiency of core physical uncertainty analysis based on sampling statistics, the proper orthogonal decomposition (POD) and Galerkin projection method were combined to study the application feasibility of reduced-order model ...
In order to improve the efficiency of core physical uncertainty analysis based on sampling statistics, the proper orthogonal decomposition (POD) and Galerkin projection method were combined to study the application feasibility of reduced-order model based on POD-Galerkin method in core physical uncertainty analysis. The two-dimensional two group TWIGL benchmark question was taken as the research object, the key variation characteristics of the core flux distribution were extracted under the finite perturbation of the group constants of each material region, and the full-order neutron diffusion problem was projected on the variation characteristics to establish a reduced-order neutron diffusion model. The reduced-order model was used to replace the full-order model to carry out the uncertainty analysis of the group constants of the material region. The results show that the bias of the mathematical expectation of keff calculated by reduced-order and full-order models is close to 1 pcm. In addition, compared with the calculation time required for uncertainty analysis of full-order model, the analysis time of reduced-order model (including the calculation time of the full-order model required for the construction of reduced-order model) is only 11.48%, which greatly improves the efficiency of uncertainty analysis. The biases of mathematical expectation of keff calculated by reduced-order and full-order models based on Latin hypercube sampling and simple random sampling are less than 8 pcm, and under the same sample size, the bias from the Latin hypercube sampling result is smaller. From the TWIGL benchmark test results, under the same sample size, Latin hypercube sampling method is more recommended for POD-Galerkin reduced-order model.
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Land, 2021 Agricultural land is fundamental to human survival and economic development. Unlike other resources, land resources are embodied in trade goods and commodities, which are continuously re-allocated between countries and regions.
Mengyao Han, Shuchang Li
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Decomposition analysis of the pollution intensities in the case of the United Kingdom
Cogent Economics & Finance, 2017 This paper examines the changes to pollution intensities (SO2, NOx, CO and CO2) of the United Kingdom, by using the Divisia index decomposition technique.
Kenichi Shimamoto
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The driving forces behind the change in energy consumption in developing countries
Environmental Research Letters, 2021 Economic growth is principally powered by energy fuels. While the potential energy transition pathways in developed countries are clear, they have not been well explored for developing countries.
Shuping Li +6 more
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Singular value decomposition applied to compact binary coalescence gravitational-wave signals [PDF]
, 2010 We investigate the application of the singular value decomposition to compact-binary, gravitational-wave data-analysis. We find that the truncated singular value decomposition reduces the number of filters required to analyze a given region of parameter ...
Adrian Chapman +7 more
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A sparse decomposition of low rank symmetric positive semi-definite matrices [PDF]
, 2016 Suppose that $A \in \mathbb{R}^{N \times N}$ is symmetric positive semidefinite with rank $K \le N$. Our goal is to decompose $A$ into $K$ rank-one matrices $\sum_{k=1}^K g_k g_k^T$ where the modes $\{g_{k}\}_{k=1}^K$ are required to be as sparse as ...
Hou, Thomas Y. +2 more
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Spectral proper orthogonal decomposition and its relationship to dynamic mode decomposition and resolvent analysis [PDF]
, 2018 We consider the frequency domain form of proper orthogonal decomposition (POD) called spectral proper orthogonal decomposition (SPOD). Spectral POD is derived from a space-time POD problem for statistically stationary flows and leads to modes that each ...
Colonius, Tim +2 more
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Characterising genome architectures using genome decomposition analysis [PDF]
BMC Genomics, 2021 AbstractGenome architecture describes how genes and other features are arranged in genomes. These arrangements reflect the evolutionary pressures on genomes and underlie biological processes such as chromosomal segregation and the regulation of gene expression.
Eerik Aunin +2 more
openaire +4 more sources
Health inequality among rural elder residents in Shaanxi province
Zhongguo gonggong weisheng, 2022 ObjectiveTo explore the status and contributing factors of health inequality among rural elder residents in Shaanxi province．MethodsThe data on 6 857 rural elderly aged 65 years and over were extracted from the dataset of Fifth National Health Services ...
Dan LI, Zhong-liang ZHOU, Dan-tong ZHAO
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Eigenvalue Decomposition as a Generalized Synchronization Cluster Analysis [PDF]
, 2007 Motivated by the recent demonstration of its use as a tool for the detection and characterization of phase-shape correlations in multivariate time series, we show that eigenvalue decomposition can also be applied to a matrix of indices of bivariate phase
Anderson T. W. +3 more
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