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Rui Xiong

Publications and source records attributed to Rui Xiong.

At least 55 records · Page 3Linked to original sources
arXiv2023

Comprehensive performance comparison among different types of features in data-driven battery state of health estimation

Battery state of health (SOH), which informs the maximal available capacity of the battery, is a key indicator of battery aging failure. Accurately estimating battery SOH is a vital function of the battery management system that remains to be addressed. In this study, a physics-informed Gaussian process regression (GPR) model is developed for battery SOH estimation, with the performance being systematically compared with that of different types of features and machine learning (ML) methods. The method performance is validated based on 58826 cycling data units of 118 cells. Experimental results show that the physics-driven ML generally estimates more accurate SOH than other non-physical features under different scenarios. The physical features-based GPR predicts battery SOH with the errors being less than 1.1% based on 10 to 20 mins' relaxation data. And the high robustness and generalization capability of the methodology is also validated against different ratios of training and test data under unseen conditions. Results also highlight the more effective capability of knowledge transfer between different types of batteries with the physical features and GPR. This study demonstrates the excellence of physical features in indicating the state evolution of complex systems, and the improved indication performance of these features by combining a suitable ML method.

eess.SY↗
arXiv2023

Design of the offline test electronics for the nozzle system of proton therapy

A set of nozzle equipment for proton therapy is now being developed at China Institute of Atomic Energy. To facilitate the off-line commissioning of the whole equipment, a set of ionization chamber signal generation system, the test electronics, is designed. The system uses ZYNQ SoC as the main control unit and outputs the beam dose analog signal through DAC8532. The dual SPDT analog switch, DG636, is used to simulate the beam position signals according to Gaussian distribution. The results show that the system can simulate the beam position, dose, and other related analog signals generated by the proton beam when passing through the ionization chamber. Moreover, the accuracy of the simulated beam position is within +/-0.33mm, and the accuracy of the simulated dose signal is within +/-1%. At the same time, it can output analog signals representing environmental parameters. The test electronics meets the design requirements, which can be used to commission the nozzle system as well as the treatment control system without the proton beam.

physics.acc-ph↗
arXiv2023

Automorphisms of the Quantum Cohomology of the Springer Resolution and Applications

In this paper, we introduce quantum Demazure--Lusztig operators acting by ring automorphisms on the equivariant quantum cohomology of the Springer resolution. Our main application is a presentation of the torus-equivariant quantum cohomology in terms of generators and relations. We provide explicit descriptions for the classical types. We also recover Kim's earlier results for the complete flag varieties by taking the Toda limit.

math.AG↗
arXiv2023

Structure algebras, Hopf algebroids and oriented cohomology of a group

We prove that the structure algebra of a Bruhat moment graph of a finite real root system is a Hopf algebroid with respect to the Hecke and the Weyl actions. We introduce new techniques (reconstruction and push-forward formula of a product, twisted coproduct, double quotients of bimodules) and apply them together with our main result to linear algebraic groups, to generalized Schubert calculus, to combinatorics of Coxeter groups and finite real root systems. As for groups, it implies that the natural Hopf-algebra structure on the algebraic oriented cohomology $h(G)$ of Levine-Morel of a split semi-simple linear algebraic group $G$ can be lifted to a `bi-Hopf' structure on the $T$-equivariant algebraic oriented cohomology of the complete flag variety. As for the Schubert calculus, we prove several new identities involving (double) generalized equivariant Schubert classes. As for finite real root systems, we compute the Hopf-algebra structure of `virtual cohomology' of dihedral groups $I_2(p)$, where $p$ is an odd prime.

math.AG↗
arXiv2023

In-situ electrical and thermal transport properties of FeySe1-xTex films with ionic liquid gating

We combine in-situ electrical transport and Seebeck coefficient measurements with the ionic liquid gating technique to investigate superconductivity and the normal state of FeySe1-xTex (FST) films. We find that the pristine FST films feature a non-Fermi liquid temperature dependence of the Seebeck coefficient, i.e., S/T ~ AS lnT, and AS is strongly correlated with the superconducting transition temperature (Tc). Ionic liquid gating significantly raises Tc of FST films, for which the Seebeck coefficient displays a novel scaling behavior and retains the logarithmic temperature dependence. Moreover, a quantitative relationship between the slope of T-linear resistivity (A\r{ho}) and Tc for gated films is observed, i.e., (A\r{ho})1/2 ~ Tc, consistent with previous reports on cuprates and FeSe. The scaling behaviors of AS and A\r{ho} point to a spin-fluctuation-associated transport mechanism in gated FeySe1-xTex superconductors.

cond-mat.supr-con↗
arXiv2022

Pieri and Murnaghan--Nakayama type Rules for Chern classes of Schubert Cells

We develop Pieri type as well as Murnaghan--Nakayama type formulas for equivariant Chern--Schwartz--MacPherson classes of Schubert cells in the classical flag variety. These formulas include as special cases many previously known multiplication formulas for Chern--Schwartz--MacPherson classes or Schubert classes. We apply the equivariant Murnaghan--Nakayama formula to the enumeration of rim hook tableaux.

math.CO↗
arXiv2022

Epitaxial growth of a two-dimensional topological insulator candidate: monolayer Si2Te2

Hexagonal Si2Te2 monolayers (ML-Si2Te2) were predicted to show strain-dependent band-crossover between semiconducting and room-temperature quantum spin Hall phases. However, investigations on this artificial two-dimensional (2D) material have mainly been restricted to theoretical calculations because its bulk counterpart does not exist naturally. Here, we report on the successful epitaxial growth of ML-Si2Te2 films on Sb2Te3 thin film substrates. High-quality (1*1) ML-Si2Te2 films with a coverage as high as 95% were obtained as revealed by scanning tunneling microscopy. X-ray photoelectron spectroscopy confirms the absence of intermixing between Si2Te2 and Sb2Te3 at the interface. By combining scanning tunneling spectroscopy with density functional theory calculations, we demonstrate the semiconducting band structure of ML-Si2Te2 on Sb2Te3. Furthermore, it is theoretically predicted that the system can be driven into the nontrivial phase via reducing the strain by 4.4% using strain engineering. Our results pave the way for in-depth investigations on this 2D topological insulator candidate.

cond-mat.mtrl-sci↗
arXiv2022

A Geometric Realization of Symmetric Pairs of Type AIII

In this paper, we construct a geometric realization of symmetric pair of type AIII over $σ$-quiver varieties as an analogy of the construction over Nakajima quiver varieties. To achieve this, we define the action of generators by pull back and push forward through $ι$Hecke correspondences and check the relations.

math.RT↗
arXiv2021

Cauchy Formulas and Billey's Formulas for Generalized Grothendieck polynomials

We study the generalized double $β$-Grothendieck polynomials for all types. We study the Cauchy formulas for them. Using this, we deduce the K-theoretic version of the comodule structure map $α^*: K(G/B)\to K(G)\otimes K(G/B)$ induced by the group action map for reductive group $G$ and its flag variety $G/B$. Furthermore, we give a combinatorial formula to compute the localization of Schubert classes as a generalization of Billey's formula.

math.CO↗
arXiv2021

Computations of the Comodule Structures of the Chow rings of Flag Varieties

Let $G$ be a connected reductive group, and $G/B$ be its flag variety. Let $π:G\to G/B$ be the natural projection. In this paper, we developed an algorithm to describe the map $π^* :\operatorname{CH}^*(G/B;\mathbb{F}_p)\longrightarrow \operatorname{CH}^*(G;\mathbb{F}_p)$ in terms of Schubert cells. Taking advantage of the Pieri rule, we give an explicit formula for $A$-type, $C$-type, $G_2$, $F_4$ of the cohomology map $π^* :\operatorname{CH}^*(G/B;\mathbb{F}_p)\longrightarrow \operatorname{CH}^*(G;\mathbb{F}_p)$, and some partial result of $π^*$ is given for $E_6$ and $E_7$. Denote the group action map $μ:G\times G/B\to G/B$, we also give an explicit formula for $A$-type, $C$-type, $G_2$, $F_4$ of the cohomology map $μ^*: \operatorname{CH}^*(G/B;\mathbb{F}_p)\longrightarrow \operatorname{CH}^*(G\times G/B;\mathbb{F}_p)$.

math.AG↗
arXiv2020

Puzzle Model for Bumpless Pipe Dream

In this note, a new puzzle is introduced where the pipe dream and bumpless pipe dream can be played simultaneously. Using these, a combinatorial proof of the (ordinary) Schubert polynomials in terms of bumpless pipe dream is given. The main tool is the Yang--Baxter equation.

math.CO↗
arXiv2020

Comodule Structures, Equivariant Hopf Structures, and Generalized Schubert Polynomials

In this article, the comodule structure of Chow rings of Flag manifolds $\operatorname{CH}(G/B)$ is described by Schubert cells. Its equivariant version gives rise to a Hopf structure of the equivariant cohomology of flag manifolds $H^*_B(G/B)$. We get two identities of generalized Schubert polynomials as explanations of the geometric facts.

math.RT↗
arXiv2020

A bijection proof of the Capelli's identity

In this article, a short combinatorial proof of the Capelli's identity is given. It also leads to an easy proof of the Capelli--Cauchy--Binet identity, a more general form of Capelli's identity. With the technique introduced, the Turnbull's identity can be proven by sum with signs. At the end of the article, the general Cayley identity is discussed as a dual version of Capelli's identity.

math.CO↗
arXiv2020

Schur Polynomials through Lindström Gessel Viennot Lemma

In this article, we use Lindström Gessel Viennot Lemma to give a short, combinatorial, visualizable proof of the identity of Schur polynomials -- the sum of monomials of Young tableaux equals to the quotient of determinants. As a by-product, we have a proof of Vandermonde determinant without words. We also prove the cauchy identity. In the remarks, we discuss factorial Schur polynomials, dual Cauchy identity and the relation beteen Newton interpolation formula.

math.CO↗
arXiv2020

Kernel-Cokernel Sequence for Composition and its Applications

If this article, an elementary kernel-cokernel exact sequence is introduced for $A\stackrel{f}\to B\stackrel{g}\to C$. Some relative sequences and applications are dicussed. This result can simplify some proofs---the indices of Frodholm operators, Harada and Sai theorem, and the derived couples of exact couples.

math.RA↗
arXiv2020

Direct proof of Mckay Correspondence and the representations of finite subgroups of $\operatorname{SO}(4)$

The classic Mckay correspondence gives a connection between finite subgroups of $\operatorname{SU}(2)$ and the simply-laced Dynkin diagrams. In this article, a direct proof is presented. The bipartite structure of the Mckay diagrams is introduced. After that, the similar method can be used on finite subgroups of $\operatorname{SO}(4)$, we get a edges-coloured graph. We finally get some applications.

math.RT↗
arXiv2019

On the structure of submodule of finitely generated module over PID

Consider $\mathbb{Z}/8\mathbb{Z}\oplus \mathbb{Z}/2\mathbb{Z}$, and the subgroup generated by $(2,1)$, it is a subgroup isomorphic to $\mathbb{Z}/4\mathbb{Z}$. If my theorem holds, it must contained in a cyclic group generated by some element of order $8$ which is impossible. The error in 4.2 is because "preimage" do not preserce the image of $[x\mapsto px]$.

math.RA↗