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DISTRIBUTION LAW OF random UNBALANCE RESPONSE OF MULTISTAGE BLOWER

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中国有色金属学会会刊：英文版 1998年第1期8卷 165-168页

作者： Tan, Qing Zhong, Jue Central South Univ of Technology Changsha China

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关键词： unbalance distribution random experiment method vibration response centrifugal blower overcritical rotating speed autobalance technology working condition diagnosis

Temperature-dependent phonon spectra of magnetic random solid solutions

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npj Computational Materials 2018年第1期4卷 606-612页

作者： Yuji Ikeda Fritz Körmann Biswanath Dutta Abel Carreras Atsuto Seko Jörg Neugebauer Isao Tanaka Department of Materials Science and Engineering Kyoto UniversityKyoto 606-8501Japan Center for Elements Strategy Initiative for Structural Materials(ESISM) Kyoto UniversityKyoto 606-8501Japan Max-Planck-Institut für Eisenforschung GmbH D-40237 DüsseldorfGermany Department of Materials Science and Engineering Delft University of TechnologyMekelweg 22628 CD DelftNetherlands Precursory Research for Embryonic Science and Technology(PRESTO) Japan Science and Technology Agency(JST)Kawaguchi 332-0012Japan Center for Materials Research by Information Integration National Institute for Materials Science(NIMS)Tsukuba 305-0047Japan Nanostructures Research Laboratory Japan Fine Ceramics CenterNagoya 456-8587Japan

A first-principles-based computational tool for simulating phonons of magnetic random solid solutions including thermal magnetic fluctuations is developed.The method takes fluctuations of force constants due to magnetic excitations as well as due to chemical disorder into account.The developed approach correctly predicts the experimentally observed unusual phonon hardening of a transverse acoustic mode in Fe–Pd an Fe–Pt Invar alloys with increasing temperature.This peculiar behavior,which cannot be explained within a conventional harmonic picture,turns out to be a consequence of thermal magnetic fluctuations.The proposed methodology can be straightforwardly applied to a wide range of materials to reveal new insights into physical behaviors and to design materials through computation,which were not accessible so far.

关键词： magnetic random phonon

NUMERICAL METHOD AND random ANALYSIS OF CEMENT CONCRETE EXPANSION

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维普期刊数据库

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Journal of Wuhan University of Technology(Materials Science) 2000年第1期15卷 66-72页

作者：管昌生 Wuhan University of Technology China Inst. of Arch. and Civil Engineering Wuhan University of Technology Wuhan 430070 China Wuhan Tech. Univ. Surv. and Mapping China Arizona State University United States

The numerical method and random anal- ysis of cement concreteexpansion are given. A mathematical procedure is presented whichincludes the nonlinear charac- teristis of the concrete. Anexpression is presented to pre- dict the linear restrained expansionof expansive concrete bar restrained by a steel rod. The resultsindicate a rapid change in strains and stresses within initial days,after which the change gradually decreases.

关键词： expansive concrete random bulkhead

Mapping landslide susceptibility at the Three Gorges Reservoir, China, using gradient boosting decision tree,random forest and information value models

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Journal of Mountain Science 2020年第3期17卷 670-685页

作者： CHEN Tao ZHU Li NIU Rui-qing TRINDER C John PENG Ling LEI Tao Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Geomatics Technology and Application key Laboratory of Qinghai Province Xining 810001China School of Civil and Environmental Engineering The University of New South WalesSydneyNSW 2052Australia China Institute of Geo-Environment Monitoring Beijing 100081China School of Electronical and Information Engineering Shaanxi University of Science and TechnologyXi’an 710021China

This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, China by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting decision tree(GBDT), random forest(RF) and information value(InV) models, were used, and the performances were assessed and compared. In total, 202 landslides were mapped by using a series of field surveys, aerial photographs, and reviews of historical and bibliographical data. Nine causative factors were then considered in landslide susceptibility map generation by using the GBDT, RF and InV models. All of the maps of the causative factors were resampled to a resolution of 28.5 m. Of the 486289 pixels in the area,28526 pixels were landslide pixels, and 457763 pixels were non-landslide pixels. Finally, landslide susceptibility maps were generated by using the three machine learning models, and their performances were assessed through receiver operating characteristic(ROC) curves, the sensitivity, specificity,overall accuracy(OA), and kappa coefficient(KAPPA). The results showed that the GBDT, RF and In V models in overall produced reasonable accurate landslide susceptibility maps. Among these three methods, the GBDT method outperforms the other two machine learning methods, which can provide strong technical support for producing landslide susceptibility maps in TGR.

关键词： Mapping landslide susceptibility Gradient boosting decision tree random forest Information value model Three Gorges Reservoir

The limiting theorems of random quadratic forms and their application

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Science China Mathematics 2005年第4期48卷 493-502页

作者： PAN Guangming MIAO Baiqi TAN Changchun Department of Statistics and Finance University of Science and Technology of China Hefei230026 China Department of Statistics and Finance University of Science and Technology of China Hefei230026 China Department of Statistics and Finance University of Science and Technology of China Hefei230026 China

The strong convergence and convergence rate of the random quadratic formss1T(S1S1T)ms1 and s1T(SST)ms1 are set up. The application of these results in wireless communication is given. Simulation results are presented.

关键词： random quadratic forms, large dimensional matrix, martingale difference, strong convergence.

THE VALUE DISTRIBUTION OF random ANALYTIC DIRICHLET SERIES OF NEUTRAL GROWTH(I)

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Acta Mathematica Scientia 1999年第2期19卷 234-240页

作者：丁晓庆 Department of Mathematics Wuhan University Wuhan 430072 China

This paper deals with the value distribution of random Dirichlet series whose coefficients are a martingale difference sequence, and which is of neutral growth.

关键词： Value distribution random Dirichlet series martingale difference sequence.

Non-Gaussian random Bi-matrix Models for Bi-free Central Limit Distributions with Positive Definite Covariance Matrices

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Acta Mathematica Sinica,English Series 2019年第12期35卷 1891-1905页

作者： Ming Chu GAO School of Mathematics and Information Science Baoji University of Arts and Sciences Department of Mathematics Louisiana College

In this paper,we construct random two-faced families of matrices with non-Gaussian entries to approximate a bi-free central limit distribution with a positive definite covariance matrix.We prove that,under modest conditions weaker than independence,a family of random two-faced families of matrices with non-Gaussian entries is asymptotically bi-free from a two-faced family of constant diagonal matrices.

关键词： Bi-free central limit distributions non-Gaussian random matrices asymptotic bi-freeness

Rock-soil slope stability analysis by two-phase random media and finite elements

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Geoscience Frontiers 2018年第6期9卷 1649-1655页

作者： Yong Liu Huawen Xiao Kai Yao Jun Hu Hong Wei State Key Laboratory of Water Resources and Hydropower Engineering Science Institute of Engineering Risk and Disaster Prevention Wuhan University Department of Civil & Environmental Engineering National University of Singapore College of Civil Engineering and Architecture Hainan University

To investigate the strong random nature of the geometric interfaces between soil and rock, a rock-soil slope is considered as a two-phase random medium. A nonlinear translation of a Gaussian field is utilized to simulate the two-phase random media, such that the soil(or rock) volume fraction and the inclination of the soil layer can be examined. The finite element method with random media incorporated as the material properties is used to determine the factor of safety of the rock-soil slope. Monte-Carlo simulations are used to estimate the statistical characteristics of the factor of safety. The failure mode of the rock-soil slope is examined by observing the maximum principal plastic strain at incipient slope failure. It is found that the critical surface of a rock-soil slope is fairly irregular, and it significantly differs from that of a pure soil slope. The factor of safety is sensitive to the soil volume faction, but it is predictable. The average factor of safety could be well predicted by the weighted harmonic average between the strength of soil and rock; the prediction model is practical and simple. Parametric studies on the inclination of the soil layer demonstrate that the most instable scenario occurs when the slope angle is consistent with the inclination of the soil layer.

关键词： Slopes stability Numerical computation Statistical analysis Finite-element modelling random fields Monte-Carlo simulations

Prediction of miRNA-circRNA Associations Based on k-NN Multi-Label with random Walk Restart on a Heterogeneous Network

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Big Data Mining and Analytics 2019年第4期2卷 261-272页

作者： Zengqiang Fang Xiujuan Lei College of Computer Science Shaanxi Normal University

Circular RNAs(circRNAs) play important roles in various biological processes, as essential non-coding RNAs that have effects on transcriptional and posttranscriptional gene expression regulation. Recently, many studies have shown that circRNAs can be regarded as micro RNA(miRNA) sponges, which are known to be associated with certain diseases. Therefore efficient computation methods are needed to explore miRNAcircRNA interactions, but only very few computational methods for predicting the associations between miRNAs and circRNAs exist. In this study, we adopt an improved random walk computational method, named KRWRMC, to express complicated associations between miRNAs and circRNAs. Our major contributions can be summed up in two points. First, in the conventional random Walk Restart Heterogeneous(RWRH) algorithm, the computational method simply converts the circRNA/miRNA similarity network into the transition probability matrix;in contrast,we take the influence of the neighbor of the node in the network into account, which can suggest or stress some potential associations. Second, our proposed KRWRMC is the first computational model to calculate large numbers of miRNA-circRNA associations, which can be regarded as biomarkers to diagnose certain diseases and can thus help us to better understand complicated diseases. The reliability of KRWRMC has been verified by Leave One Out Cross Validation(LOOCV) and 10-fold cross validation, the results of which indicate that this method achieves excellent performance in predicting potential miRNA-circRNA associations.

关键词： miRNA-circRNA associations heterogeneous network multi-label random walk restart