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New breakthrough: Building non-markovian environments for single-qubit systems at any time interval

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Science China(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 193页

作者： H.z.Shen Center for Quantum Sciences and School of Physics Northeast Normal University

The proposal of quantum simulation provides a highly effective approach for experimental research on open quantum systems. To date, numerous quantum simulation studies pertaining to open quantum systems have been put forward,including Fanchini et al.’s simulation of a dephasing noise channel utiliz.ng an optical system [1], and Xiong et al.’s realiz.tion of a quantum simulation for a non-rotating-wave approximation noise channel, also leveraging an optical system [2].

关键词： quantum system breakthrough

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NEW VIEW ABOUT BAINITIC TRANSFORMATION IN STEEL

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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 229-234页

作者： liu, C.C. liu, z. Chen, G.X. Tsinghua Univ Beijing China

The bainitic transformation was analyz.d according to the factors such as morphology, crystallography, mechanical property of bainite and transformation kinetics. It was found that the bainitic transformation is controlled by displacive mechanism and self-tempering of displacive microstructure, i.e. bainite is the product of such procedure during which undercooled austenite first transforms into one certain displacive microstructure by displacive mechanism and then this microstructure experiences self-tempering. With this idea, several questions that can not be illustrated only by displacive transformation mechanism can be explained successfully.

关键词： Bainite Morphology Steel

LOW CYCLE FATIGUE BEHAVIOR OF Az.1HP ALLOY IN AS HIGHP RESSURE DIE CASTING

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Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 961-966页

作者： liu, z. Xu, Y.Y. Wang, z.G. Wang, Y. liu, z.Y. Inst of Metal Research Chinese Acad of Sciences Shenyang China

Fully reversed total strain-controlled low-cycle fatigue tests were conducted at room temperature in air to study the fatigue behavior of Az.1HP magnesium alloy in as high pressure die casting and subsequently heat treatment. All the specimens in different heat histories exhibit cyclic strain hardening in different degrees. It is difficult to distinguish the fatigue behavior of the die casting specimens from that of the solution aging specimens. The solution treated specimens show longer fatigue life at high strain amplitude and shorter fatigue life at low strain amplitude than the die casting and solution aging specimens though they have the lowest yield strength with higher strain hardening. Fatigue fracture surfaces for strain amplitude larger than 0.005 show very similar to those found by monotonic tensile tests. The SEM examination reveals that the regions of fatigue crack growth and final fracture can be characteriz.d by quasi-cleavage mechanisms, but some shallow dimples, slip bands and secondary cracks are found on the fracture surface in the fracture crack growth areas.

关键词： Cracks Die casting Fatigue of materials Heat treatment

Counterfactual Learning on Graphs:A Survey

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Machine Intelligence Research 2025年第1期22卷 17-59页

作者： z.imeng Guo z.ngyu Wu Teng Xiao Charu Aggarwal Hui liu Suhang Wang College of Information Sciences and Technology Pennsylvania State UniversityUniversity Park 16802USA International Business Machines Corporation T.J.Watson Research Center New York 10598USA College of Engineering Michigan State UniversityEast Lansing 48824USA

Graph-structured data are pervasive in the real-world such as social networks,molecular graphs and transaction *** neural networks(GNNs)have achieved great success in representation learning on graphs,facilitating various downstream ***,GNNs have several drawbacks such as lacking interpretability,can easily inherit the bias of data and cannot model casual ***,counterfactual learning on graphs has shown promising results in alleviating these *** approaches have been proposed for counterfactual fairness,explainability,link prediction and other applications on *** facilitate the develop-ment of this promising direction,in this survey,we categoriz. and comprehensively review papers on graph counterfactual *** divide existing methods into four categories based on problems *** each category,we provide background and motivating ex-amples,a general framework summariz.ng existing works and a detailed review of these *** point out promising future research directions at the intersection of graph-structured data,counterfactual learning,and real-world *** offer a comprehensive view of resources for future studies,we compile a collection of open-source implementations,public datasets,and commonly-used evalu-ation *** survey aims to serve as a“one-stop-shop”for building a unified understanding of graph counterfactual learning cat-egories and current resources.

关键词： Counterfactual learning graph-structured data graph neural networks fairness explainability

Convolutional Graph Neural Network with Novel Loss Strategies for Daily Temperature and Precipitation Statistical Downscaling over South China

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Advances in Atmospheric Sciences 2025年第1期42卷 232-247页

作者： Wenjie YAN Shengjun liu Yulin z.U Xinru liu Diyao WEN Yamin HU Dangfu YANG Jiehong XIE Liang z.AO Central South University Changsha 410083China Hunan Expressway Information Technology Co. Ltd.Changsha 410053China Guangdong Climate Center Guangzhou 510610China Hong Kong Polytechnic University Shenz.en Research Institute Guangdong 518057China Jieyang Meteorological Bureau Jieyang 522031China State Key Laboratory of Numerical Modeling for Atmosphere Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Traditional meteorological downscaling methods face limitations due to the complex distribution of meteorological variables,which can lead to unstable forecasting results,especially in extreme *** overcome this issue,we propose a convolutional graph neural network(CGNN)model,which we enhance with multilayer feature fusion and a squeez.-and-excitation ***,we introduce a spatially balanced mean squared error(SBMSE)loss function to address the imbalanced distribution and spatial variability of meteorological *** CGNN is capable of extracting essential spatial features and aggregating them from a global perspective,thereby improving the accuracy of prediction and enhancing the model's generaliz.tion *** on the experimental results,CGNN has certain advantages in terms of bias distribution,exhibiting a smaller *** it comes to precipitation,both UNet and AE also demonstrate relatively small *** for temperature,AE and CNNdense perform outstandingly during the *** time correlation coefficients show an improvement of at least 10%at daily and monthly scales for both temperature and ***,the SBMSE loss function displays an advantage over existing loss functions in predicting the98th percentile and identifying areas where extreme events ***,the SBMSE tends to overestimate the distribution of extreme precipitation,which may be due to the theoretical assumptions about the posterior distribution of data that partially limit the effectiveness of the loss *** future work,we will further optimiz. the SBMSE to improve prediction accuracy.

关键词： statistical downscaling convolutional graph neural network feature processing SBMSE loss function

Analysis of vibration reduction level in an 8/6 switched reluctance machine by active vibration cancellation

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Journal of z.ejiang University-Science C(Computers and Electronics) 2010年第10期11卷 808-816页

作者： Xu liu z.i-ping PAN z. Q. z.U School of Electrical Engineering Zhejiang University Hangzhou 310027 China Department of Electronic and Electrwal Engmeermg University of Sheffield Sheffield S1 3JD UK

This paper proposes an analytical model for predicting the maximum vibration reduction level in a four-phase 8/6 switched reluctance machine(SRM) by employing active vibration cancellation(AVC),one of the most effective and convenient methods for reducing the vibration and acoustic noise produced by *** on the proposed method,the factors that influence the vibration reduction level are analyz.d in *** relationships between vibration and noise reduction levels at resonance frequency and rotor speed are ***,it is shown that a large damping factor will lead to smaller vibration reduction level with AVC while,in contrast,a large resonance frequency will increase the vibration reduction *** finite element analyses and experiments were carried out on a prototype 8/6 SRM to validate the proposed method.

关键词： Active vibration cancellation Analytical model Switched reluctance machine Vibration

Measurement, modelling, and closed-loop control of crystal shape distribution： Literature review and future perspectives

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Particuology 2016年第3期14卷 1-18页

作者： Cai Y. Ma Jing J. liu Xue z. Wang Institute of Particle Science and Engineering School of Chemical and Process Engineering University of Leeds Leeds 1.52 9JT United Kingdom School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China

Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal siz. distribution, where the siz. of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.

关键词： Crystal morphology Crystal shape distribution Morphological population balance mode3D process imaging Closed-loop control of crystal shapeCrystal facet growth kinetics

Deterministic quantum state and gate teleportation between distant superconducting chips

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Science Bulletin 2025年第3期70卷 351-358页

作者： Jiawei Qiu Yang liu Ling Hu Yukai Wu Jingjing Niu Libo z.ang Wenhui Huang Yuanz.en Chen Jian Li Song liu Youpeng z.ong Luming Duan Dapeng Yu Shenz.en Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China International Quantum Academy Shenzhen 518048China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Center for Quantum Information Institute for Interdisciplinary Information SciencesTsinghua UniversityBeijing 100084China Department of Physics Southern University of Science and TechnologyShenzhen 518055China

Quantum teleportation is of both fundamental interest and great practical importance in quantum information *** date,quantum teleportation has been implemented in various physical systems,among which superconducting qubits are of particular practical significance as they emerge as a leading system to realiz. large-scale quantum ***,scaling up the number of superconducting qubits on a single chip becomes increasing challenging because of some emergent technical *** of quantum teleportation and remote computation over qubits on distant superconducting chips is a key quantum communication technology to scaling up the system through a distributed quantum computational ***,this goal has not been realiz.d yet in experiments due to the technical challenges including making a quantum interconnect between distant superconducting chips and the inefficient transfer of flying microwave photons over the lossy *** we demonstrate deterministic teleportation of quantum states and entangling gates between distant superconducting chips connected by a 64-m-long cable bus featuring an ultralow loss of 0.32 dB/km at cryogenic temperatures,where high fidelity remote entanglement is generated via flying microwave *** work demonstrates a prime building block for distributed quantum computation with superconducting qubits,and opens up a new avenue for waveguide quantum electrodynamics and quantum photonics at microwave frequencies.

关键词： Superconducting circuits Quantum network Quantum computing Flying microwave photon

Experimental study on the buckling of composite cylinders with reinforced circular hole under hydrostatic pressure

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Defence Technology(防务技术) 2025年第2期44卷 231-247页

作者： z.un Li Xinhu z.ang Kechun Shen Jing liu Jian z.ang Guang Pan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099China Jiangsu University of Science and Technology Zhenjiang 212003China

In this paper,a type of reinforcing structure for composite shell with single and through hole is *** experimental tests for the composite shells without hole,with single hole and reinforced structure,with through hole and reinforced structure subjected to hydrostatic pressure were carried out by the designed experimental test *** mechanical responses of the composite shells under hydrostatic pressure are obtained by the high-speed camera and strain *** results show that the entire deformation process of the shell can be divided into three:uniform compression,"buckling mode formation"and ***"buckling mode formation"process is captured and reported for the first *** the composite shell with single hole,the proposed reinforcing structure has a significant reinforcement effect on the shell and the buckling capacity of the shell is not weaker than the complete composite *** the composite shell with through hole,sealing effect can be achieved by the proposed reinforcing structure,but the buckling capacity of the shell after reinforcement can only reach 77%of the original buckling capacity.

关键词： Composite cylindrical shell Circular hole Reinforcing structure Buckling Hydrostatic pressure