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Gamma-Ray Bursts Subset and Supernova Remnants Low Radio-Frequency Turnover

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Chinese Physics Letters 2000年第8期17卷 623-624页

作者： LIU xiang Urumqi Astronomical Observatory National Astronomical ObservatoriesChinese Academy of SciencesUrumqi 830011

Durations of gamma-ray bursts(GRB's)are featured by>2s subset and<2s one,with initial corresponding energy ratio being 20:*** is found that supernova remants(SNR's)turnover frequencies peak at 100 and 500 *** assuming that GRB's originate from hypernova and making an analysis on the evolution of GRB's,we find that the initial energy of two GRB subsets leads to a different radio-frequency turnover of their remnant spectra,which accords positively with the turnover-frequency ratio of SNR's.

关键词： evolution supernova initial

Detection and Estimation of False Data Injection Attacks for Load Frequency Control Systems

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 861-870页

作者： Jun Ye xiang Yu Hangzhou Innovation Institute Beihang UniversityHangzhouChina School of Automation Science and Electrical Engineering Beihang UniversityBeijingChina

False data injection attacks(FDIAs)against the load frequency control(LFC)system can lead to unstable operation of power *** this paper,the problems of detecting and estimating the FDIAs for the LFC system in the presence of external disturbances are ***,the LFC system model with FDIAs against frequency and tie-line power measurements is ***,a design procedure for the unknown input observer(UIO)is presented and the residual signal is generated to detect the *** UIO is designed to decouple the effect of the unknown external disturbance on the residual *** that,an attack estimation method based on a robust adaptive observer(RAO)is proposed to estimate the state and the FDIAs *** order to improve the performance of attack estimation,the H¥technique is employed to minimize the effect of external disturbance on estimation errors,and the uniform boundedness of the state and attack estimation errors is proven using Lyapunov stability ***,a two-area interconnected power system is simulated to demonstrate the effectiveness of the proposed attack detection and estimation algorithms.

关键词： External disturbance false data injection attacks load frequency control robust adaptive observer unknown input observer

High durable aqueous zinc ion batteries by synergistic effect of V_(6)O_(13)/VO_(2) electrode materials

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Journal of Energy Chemistry 2023年第12期87卷 334-341,I0009页

作者： Yi Liu xiang Wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

Vanadium oxides have attracted one’s wide attention due to their diverse valences and spatial structure as cathode for aqueous zinc ion ***,a strong electrostatic interaction exists between Zn ions and host materials,which leads to their sluggish reaction kinetics and inferior structural ***,we design a kind of vanadium-based electrode materials with abundant phase boundaries and oxygen *** assembled Zn//V_(6)O_(13)/VO_(2) batteries deliver a specific capacity of 498.3 mA h g^(-1)at 0.2 A g^(-1) and retain a capacity of 485.8 mA h g^(-1)after 100 ***,they achieve a retention rate of 96.8% after 5000 cycles at 10 A g^(-1).The soft pack cells also show excellent mechanical stability at different folding conditions.

关键词： Aqueous zinc ion batteries Vanadium oxide Cathode material Phase boundary Cycling stability

A Voronoi diagram approach for detecting defects in 3D printed fiber-reinforced polymers from microscope images

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Computational Visual Media 2023年第1期9卷 41-56页

作者： xiang Li Sara McMains University of California Berkeley BerkeleyCalifornia94720USA

Fiber-reinforced polymer(FRP)composites are increasingly popular due to their superior strength to weight *** contrast to significant recent advances in automating the FRP manufacturing process via 3D printing,quality inspection and defect detection remain largely manual and *** this paper,we propose a new approach to automatically detect,from microscope images,one of the major defects in 3D printed FRP parts:fiber-deficient areas(or equivalently,resin-rich areas).From cross-sectional microscope images,we detect the locations and sizes of fibers,construct their Voronoi diagram,and employ-shape theory to determine fiber-deficient *** Voronoi diagram and-shape construction algorithms are specialized to exploit typical characteristics of 3D printed FRP parts,giving significant efficiency *** algorithms robustly handle real-world inputs containing hundreds of thousands of fiber cross-sections,whether in general or non-general position.

关键词： 3D printing(3DP) microscope image processing fiber-reinforced polymer(FRP) Voronoi diagrams -shapes resin-rich areas

Residual Stress Removal Under Pulsed Electric Current

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Acta Metallurgica Sinica(English Letters) 2020年第2期33卷 281-289页

作者： Siqi xiang Xinfang Zhang State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China

The effect of a pulsed electric current on the residual stress evolution of metal materials has been *** was found that the surface and internal residual stresses in the as-quenched samples were reduced dramatically by electropulsing.A large number of experimental data show that the residual stress reduction is proportional to the initial residual stress and related to the material properties and electropulsing *** the combined actions of drift electrons,Joule heating,and residual stress,the dislocation mobility was enhanced,resulting in plastic strain and the decrease in residual *** electrons played a unique role in the electropulsing treatment,acting as an additional force pushing dislocations *** dislocations ultimately accumulated at a grain boundary,forming a parallel ***,the phenomenological equation of the residual stress evolution under electropulsing was derived from the experimental data.

关键词： Electroplastic Residual stress Dislocation movement Phenomenological equation

Dual-ion carrier storage through Mg^(2+) addition for high-energy and long-life zinc-ion hybrid capacitor

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 179-185页

作者： Junjie Zhang xiang Wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Cation additives can efficiently enhance the total electrochemical capabilities of zinc-ion hybrid capacitors (ZHCs).However their energy storage mechanisms in zinc-based systems are still under ***,we modulate the electrolyte and achieve dual-ion storage by adding magnesium *** we assemble several Zn//activated carbon devices with different electrolyte concentrations and investigate their electrochemical reaction dynamic *** zinc-ion capacitor with Mg^(2+)mixed solution delivers 82 mAh·g^(-1)capacity at 1 A·g^(-1) and maintains 91%of the original capacitance after 10000 *** is superior to the other assembled zinc-ion devices in single-component *** finding demonstrates that the double-ion storage mechanism enables the superior rate performance and long cycle lifetime of ZHCs.

关键词： zinc-ion hybrid capacitor MgSO_(4) electrolyte rate performance storage mechanism

High Chern number phase in topological insulator multilayer structures:A Dirac cone model study

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Chinese Physics B 2022年第9期31卷 217-224页

作者： Yi-xiang Wang Fu-xiang Li School of Science Jiangnan UniversityWuxi 214122China School of Physics and Electronics Hunan UniversityChangsha 410082China

We employ the Dirac cone model to explore the high Chern number(C)phases that are realized in the magnetic-doped topological insulator(TI)multilayer structures by Zhao et al.[Nature 588419(2020)].The Chern number is calculated by capturing the evolution of the phase boundaries with the parameters,then the Chern number phase diagrams of the TI multilayer structures are *** high-C behavior is attributed to the band inversion of the renormalized Dirac cones,along with which the spin polarization at theΓpoint will get ***,another two TI multilayer structures as well as the TI superlattice structures are studied.

关键词： topological insulator multilayer Chern number phase diagram

Experimental isothermal section phase diagram of Ho-Fe-In at 773 K and magnetic properties of Ho_(12)Fe_(2.08)In_(2.92) alloy

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Rare Metals 2021年第4期40卷 987-994页

作者： xiang Chen Chao Ni The College of Physics and Electronic Information Engineering Neijiang Normal UniversityNeijiang 641002China The Ames Laboratory U.S.Department of EnergyIowa State UniversityAmesIA 50011-3020USA

The isothermal section of the Ho-Fe-In system at 773 K has been constructed by X-ray powder *** known structure ternary compound Er_(12)Fe_(2) In_(3)-type Ho_(12)Fe_(2) In_(3) has been *** the same time,solid solutions are not detected in Ho-Fe-In system at 773 *** magnetic transition and magnetocaloric effect of Ho_(12)Fe_(2.08)In_(2.92) alloy with Er_(12)Fe_(2) In_(3)-type structure were investigated by magnetic susceptibility and isothermal magnetization *** normal antiferromagnetic-paramagnetic transition and another abnormal one are discovered at 18 and 76 K in ground state,*** to a first-order field-induced metamagnetic transition(antiferromagnetic-ferromagnetic) at/below the Neel temperature of 18 K),the negative entropy changes are observed at corresponding *** is only a second-order ferromagnetic-paramagnetic transition near Curie temperature(TC),the maximum entropy change(Δ_(Smax)) values are-6.14 J·kg^(-1)·K^(-1) at 3 K and 7.88 J·kg^(-1)·K^(-1) at 28 K in a field range of 0-7 *** reversible relative cooling power corresponding to negative entropy change can reach about 600 J·kg^(-1) in an wide operating temperature region Δ_(Tcycl)=74 K from 16 to90 K,which suggests that Ho_(12)Fe_(2.08)In_(2.92) could be a potential material for magnetic refrigeration in the corresponding temperature range.

关键词： Re_(3(x+y))(T2)_(x)X_(y)phase Metamagnetic transition Magnetothermal properties Ho-Fe-In alloy

A Difference Hamiltonian Operator and a Hierarchy of Generalized Toda Lattice Equations

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Communications in Theoretical Physics 2005年第1X期44卷 1-7页

作者： XUXi-xiang YANGHong-xiang DINGHai-Yong CollegeofScience ShandongUniversityofScienceandTechnologyQingdao266510China DepartmentofComputerScienceandTechnology TaishanCollegeTaian271021China CollegeofInformationScienceandEngineering ShandongAgricultureUniversityTaian271018China

A difference Ha-miltonian operator with three arbitrary constants is presented. When the arbitrary constants -in the Hamiltonian operator are suitably chosen, a pair of Hamiltonian operators are given. The resulting Hamiltonian pair yields a difference hereditary operator. Using Magri scheme of bi-Hamiltonian formulation, a hierarchy of the generalized Toda lattice equations is constructed. Finally, the discrete zero curvature representation is given for the resulting hierarchy.

关键词： Hamiltonian算子微分函数 Hamiltonian公式遗传算子离散弯曲函数