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Topological circuit of a versatile non-Hermitian quantum system

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Science China(Physics,Mechanics & Astronomy) 2022年第1期65卷 53-60页

作者： David-Andres Galeano xiao-xiao zhang Jorge Mahecha Instituto de F´ısica Facultad de Ciencias Exactas y NaturalesUniversidad de AntioquiaMedell´ın 050010Colombia Unidad Transacciones T&D Energ´ıa Gerencia Comercial T&D Energ´ıaV.P.T&D Energ´ıaEPMMedell´ın 050015Colombia Department of Physics and Astronomy&Stewart Blusson Quantum Matter Institute University of British ColumbiaVancouver V6T 1Z4Canada RIKEN Center for Emergent Matter Science(CEMS) Saitama 351-0198Japan Department of Chemistry University of British ColumbiaVancouver V6T 1Z4Canada

We propose a resistors,inductors and capacitors(RLC)electrical circuit to theoretically analyze and fully simulate a new type of non-Hermitian Su-Schrieffer-Heeger(SSH)model with complex *** formulate its construction and investigate its properties by taking advantage of the circuit’s *** physical properties can be identified in this system from the normal modes of oscillation of the RLC circuit,including the highly tunable bulk-edge correspondence between topological winding numbers and edge states and the non-Hermitian skin phenomenon originating from a novel complex energy plane *** present study is able to show the wide and appealing topological physics inherent to electric circuits,which is readily generalizable to a plenty of both Hermitian and non-Hermitian nontrivial systems.

关键词： topolectric circuit SSH model non-Hermitian topology skin effect

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： zhang Ying xiao Gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

Analysis of Piezoelectric Semiconductor Structures Considering Both Physical and Geometric Nonlinearities

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Acta Mechanica Solida Sinica 2024年第1期37卷 72-81页

作者： Zhengguang xiao Shuangpeng Li Chunli zhang Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Department of Engineering MechanicsZhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311816China

Piezoelectric semiconductors(PSs),such as ZnO and GaN,known as the third-generation semiconductors,have promising applications in electronic and optoelectronic devices due to the coexistence and interaction of piezoelectricity and semiconductor *** modeling of PS structures under external loads,such as thermal and mechanical loads,plays a crucial role in the design of PS *** this work,we propose a nonlinear fully coupling theoretical model and investigate the multi-field coupling behaviors of PS structures and PN junctions under thermal and mechanical loads,considering physical and geometric *** electromechanical and semiconducting behaviors of a PS rod-like structure with flexural deformations under different combinations of temperature changes and mechanical loads are *** tuning effect of temperature changes and mechanical loads on multi-field coupling behaviors of PSs is *** current–voltage characteristics of PS PN junctions are studied under different combinations of temperature changes and mechanical *** obtained results are helpful for the development of novel PS devices.

关键词： Piezoelectric semiconductor Nonlinearity Multi-field Coupling Tuning

Target parameter estimation for OTFS-integrated radar and communications based on sparse reconstruction preprocessing

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 742-754页

作者： Zhenkai zhang xiaoke SHANG Yue xiao Ocean College Jiangsu University of Science and TechnologyZhenjiang 212003China

Orthogonal time-frequency space(OTFS)is a new modulation technique proposed in recent years for high Doppler wireless *** solve the parameter estimation problem of the OTFS-integrated radar and communications system,we propose a parameter estimation method based on sparse reconstruction preprocessing to reduce the computational effort of the traditional weighted subspace fitting(WSF)***,an OTFS-integrated echo signal model is ***,the echo signal is transformed to the time domain to separate the target angle from the range,and the range and angle of the detected target are coarsely estimated by using the sparse reconstruction ***,the WSF algorithm is used to refine the search with the coarse estimate at the center to obtain an accurate *** simulations demonstrate the effectiveness and superiority of the proposed parameterestimation algorithm.

关键词： Integrated radar and communications system Orthogonal time-frequency space Target parameter estimation Sparse reconstruction Weighted subspace fitting

Numerical investigation on dynamic response of the screen mesh in vibrating screening through DEM-FEM co-simulation

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Particuology 2024年第4期87卷 205-217页

作者： Huan zhang xiao Zheng Weimin Jing Key Laboratory of MetallurgicalEquipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081 China Hubei Key Laboratory of Mechanical Transmssion and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400044China

Dynamic response of the screen mesh is of great significance in the optimum vibrating screen *** this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle ***,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen ***,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the ***,the influence of screening parameters on LVA and its distribution was *** results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.

关键词： Vibrating screen Dynamic response DEM-FEM Screening parameters Local vibration amplitude

Surgical treatment of Pitt-Hopkins syndrome associated with strabismus and early-onset myopia:Two case reports

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World Journal of Clinical Cases 2022年第34期10卷 12734-12741页

作者： Ying Huang Yue Di xiao-xiao zhang Xin-Yue Li Wang-Yi Fang Tong Qiao Department of Ophthalmology Shanghai Children's HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200062China

BACKGROUND Pitt-Hopkins syndrome(PTHS;MIM#610954)is a rare genetic neurological *** and strabismus have been reported in approximately 50%of PTHS *** studies have reported details about the required surgery for PTHS with strabismus and early-onset ***,we retrospectively reviewed the surgical management of two patients with PTHS combined with strabismus and/or early-onset *** SUMMARY A 5-year-old girl presented with congenital esotropia and left eye myopia,and the second girl was a 5-year-old girl who presented with intermittent *** testing performed on both patients showed a mutation in transcription factor 4,which is a diagnostic marker of *** first girl underwent bilateral medial rectus recession combined with posterior scleral reinforcement(PSR)in the left eye and the second patient underwent bilateral lateral rectus recession strabismus *** made key innovations in surgical timing and strategy,and the results were *** combination of strabismus and PSR surgery is an innovative strategy for patients with both strabismus and early-onset *** Early treatment of strabismus and myopia positively influence motor development and should be included in rehabilitation programs for patients with PTHS.

关键词： Pitt-Hopkins syndrome Transcription factor 4 Strabismus Myopia Surgery Case report

Accurate Distinction of Weak and Strong AC Grids for Emerging Hierarchical-Infeed LCC-UHVDC Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 772-777页

作者： Hao xiao Xianzhong Duan Yi zhang Department of Electrical and Computer Engineering University of ManitobaWinnipeg R3T 2N2ManitobaCanada State Key Laboratory of Advanced Electromagnetic Engineering and Technology Hubei Electric Power Security and High Efficiency Key LaboratorySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina RTDS Technologies Inc. Winnipeg R3T 2E1ManitobaCanada

Distinction of weak and strong AC grids for emerging hierarchical-infeed LCC-UHVDC systems is important for planning and operation departments. However, accuracy of earlier distinction methods is limited as they were developed by empirical reasoning without rigorous theoretical analysis. Hence in this letter, hierarchical-infeed interactive effective short-circuit ratio (HIESCR) index is first used for strength evaluation of HIDC systems with complex inter-inverter interactions considered. Boundary HIESCR (BHIESCR) is also introduced in the proposed distinction method of weak and strong AC grids. That is, weak (or strong) AC grids are, respectively, identified when HIESCR is less (or greater) than BHIESCR. Second, it is shown BHIESCR remains almost unchanged as 3.0 versus various system parameters and rated operation variables based on rigorous theoretical analysis. This salient feature makes the proposed method more accurate than earlier methods. Finally, the proposed method is validated by simulations based on the PSCAD/EMTDC program.

关键词： Hierarchical-Infeedinteractive effective short-circuit ratio hierarchical-infeed LCC-UHVDC systems inter-inverter interactions strong AC grids weak AC grids

Characterizations of semihoops based on derivations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 291-310页

作者： WANG Mei zhang xiao-hong School of Electrical and Control Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Arts and Sciences Shaanxi University of Science and TechnologyXi'an 710021China School of Mathematics and Statistics Weinan Normal UniversityWeinan 714099China

In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of ***,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative ***,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence.

关键词： (prelinear)semihoop derivation Heyting algebra Galois connection

Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： Xue-qin Ji xiao-song zhang Chen-jun Yang xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai Marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces