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Statistical characteristics and classification of ionospheric mid-latitude trough as revealed by the observations of DMSP-F18

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Earth and Planetary Physics 2025年第1期9卷 137-147页

作者： yi Liu JiuHou Lei FuQing Huang su.Zhou School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Science Guiyang UniversityGuiyang 550005China

Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program F18(DMSP-F18)*** data was obtained at an altitude of around 860 km in near polar orbit,throughout *** study identified the auroral boundary based on the in-situ electron density and electron spectrum,allowing us to precisely determine the location of the mid-latitude *** differs from most previous works,which only use Total Electron Content(TEC)or in-situ electron *** our study,the troughs exhibited a higher occurrence rate in local winter than in su.mer,and extended to lower latitudes with increasing geomagnetic *** was found that the ionospheric mid-latitude trough,which is associated with temperature changes or enhanced ion drift,exhibited distinct ***,the ionospheric mid-latitude troughs related to electron temperature(Te)peak were located more equatorward of auroral oval boundary in winter than in *** ionospheric mid-latitude troughs related to Te-maximum were less frequently observed at 60−70°S magnetic latitude and 90−240°E ***,the troughs related to ion temperature(Ti)maximums were observed at relatively higher latitudes,occurring more frequently in *** addition,the troughs related to ion velocity(Vi)maximums could be observed in all *** troughs with the maximum-Ti and maximum-Vi were located closer to the equatorward boundary of the auroral oval at the nightside,and in both *** implies that enhanced ion drift velocity contributes to increased collisional frictional heating and enhanced ion temperatures,resu.ting in a density depletion within the trough region.

关键词： topside ionosphere mid-latitude trough ionospheric main trough auroral oval boundary temperature maximum

Dissipation-free approach for realizing non-Hermitian dynamics in a su.erconducting circuit

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： yi-Hao Kang Yang Xiao Yu Wang Qi-Ping su.Chui-Ping Yang School of Physics Hangzhou Normal University Fujian Key Laboratory of Quantum Information and Quantum Optics Fuzhou University Department of Physics Fuzhou University

Non-Hermitian dynamics exhibits a wealth of su.prising and potentially useful phenomena. However, it is typically realized by coupling a system with thermal reservoirs, which makes the system su.fer from thermal fluctuations associated with the dissipation. Here, we propose a dissipation-free approach to realize non-Hermitian dynamics using a su.erconducting circuit composed of two resonators and a su.erconducting qutrit. The non-Hermiticity arises in the dynamical matrix for the evolution of the two resonators in the Heisenberg picture, via a photon-number non-conserved dynamics. The energy spectrum of the non-Hermitian dynamical matrix can be retrieved by measu.ing the state of the two resonators, and a phase transition of the energy spectrum can be observed by varying the control parameters. In the realization of the non-Hermitian dynamics, the dissipation of the system and the post-selection are not required. Thus, the approach is implemented in a deterministic way, and the reservoir-induced noise is su.pressed. Numerical simulations indicate that the energy spectrum of the non-Hermitian dynamical matrix obtained via the measu.ement of the resonators is in accordance with the theoretical prediction. Moreover, we demonstrate the parity discrimination for the state of two four-level qudits as an application, exhibiting the potential of the non-Hermitian dynamics in the field of quantum measu.ement. This work opens a new avenue for the realization of non-Hermitian dynamics and may have a significant implication in exploring the non-Hermitian phenomena.

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Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang yi-De Zhang Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-yian Guo Jian-Gang Shen su.Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** resu.ts showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** su.gests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Observability Analysis and Navigation Algorithm for Distributed Satellites System Using Relative Range Measu.ements

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Journal of Systems Science & Complexity 2018年第5期31卷 1206-1226页

作者： su.Qiya HUANG yi Beijing Institute of Remote Sensing Equipment Beijing 100854 China Key Laboratory of Systems and Control Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China School of Mathematical Sciences University of Chinese Academy of Sciences Beijing 100049 China

The problem of navigation for the distributed satellites system using relative range mea- su.ements is investigated. Firstly, observability for every participating satellites is analyzed based on the nonlinear Keplerian model containing J2 perturbation and the nonlinear measu.ements. It is proven that the minimum number of tracking satellites to assu.e the observability of the distributed satellites system is three. Additionally, the analysis shows that the J2 perturbation and the nonlinearity make little contribution to improve the observability for the navigation. Then, a quasi-consistent extended Kalman filter based navigation algorithm is proposed, which is quasi-consistent and can provide an on- line evaluation of the navigation precision. The simulation illustrates the feasibility and effectiveness of the proposed navigation algorithm for the distributed satellites system.

关键词： Distributed satellites system (DSS) navigation observability quasi-consistent extendedKalman filter (QCEKF) relative range.

Two-stage Optimal Dispatching of AC/DC Hybrid Active Distribution Systems Considering Network Flexibility

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 52-65页

作者： yi su.Jiashen Teh School of Electrical and Electronic Engineering Universiti Sains Malaysia(USM)14300 Nibong TebalPenangMalaysia IEEE

The increasing flexibility of active distribution systems(ADSs)coupled with the high penetration of renewable distributed generators(RDGs)leads to the increase of the *** is of practical significance to achieve the largest amount of RDG penetration in ADSs and maintain the optimal *** study establishes an alternating current(AC)/direct current(DC)hybrid ADS model that considers the dynamic thermal rating,soft open point,and distribution network reconfiguration(DNR).Moreover,it transforms the optimal dispatching into a second-order cone programming *** the different control time scales of dispatchable resources,the following two-stage dispatching framework is proposed.d dispatch uses hourly input data with the goal(1)The day-ahea of minimizing the grid loss and RDG *** obtains the optimal 24-hour schedule to determine the dispatching plans for DNR and the energy storage system.(2)The intraday dispatch uses 15-min input data for 1-hour rolling-plan dispatch but only executes the first 15 min of *** eliminate error between the actual operation and dispatching plan,the first 15 min is divided into three 5-min step-by-step *** goal of each step is to trace the tie-line power of the intraday rolling-plan dispatch to the greatest extent at the minimum *** measu.ed data are used as feedback input for the rolling-plan dispatch after each step is executed.A case study shows that the comprehensive cooperative ADS model can release the line capacity,reduce losses,and improve the penetration rate of ***,the two-stage dispatching framework can handle source-load fluctuations and enhance system stability.

关键词： Two-stage dispatching network flexibility renewable distributed generator second-order cone programming(SOCP) alternating current(AC)/direct current(DC)hybrid active distribution system

Hybrid Block Diagonalization Precoding for Multi-User Weighted su.-Rate Maximization

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China Communications 2024年第8期21卷 127-141页

作者： su.Xiaofeng Jiang yi Key Laboratory for Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringFudan UniversityShanghai 200433China

This paper studies large-scale multi-input multi-output(MIMO)orthogonal frequency division multiplexing(OFDM)communications in a broadband frequency-selective channel,where a massive MIMO base station(BS)communicates with multiple users equipped with *** develop a hybrid precoding design to maximize the weighted su.-rate(WSR)of the users by optimizing the digital and the analog precoders *** the digital part,we employ block-diagonalization to eliminate inter-user interference and apply water-filling power allocation to maximize the *** the analog part,the optimization of the PSN is formulated as an unconstrained problem,which can be efficiently solved by a gradient descent *** resu.ts show that the proposed block-diagonal hybrid precoding algorithm can outperform the existing works.

关键词： block-diagonal gradient descent hybrid precoding iterative optimization MIMO-OFDM multi-user water-filling power allocation weighted su.-rate maximization

易地扶贫搬迁脱贫人口的人力资本、生计模式与脱贫脆弱性——基于凉山彝区大型易地扶贫搬迁安置点的调研分析

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云南农业大学学报（社会科学版） 2025年第1期19卷 158-166页

作者：唐亮李雪苏艺泸州职业技术学院泸州商学院四川泸州646000 四川农业大学经济学院四川成都611130 四川省社会科学院农村发展研究所四川成都610072

基于凉山彝区大型易地扶贫搬迁安置点1034户脱贫家庭的调研数据,实证分析人力资本对脱贫脆弱性的影响及作用机制。研究发现:部分脱贫户的脱贫较为脆弱,但能够守住不发生规模性返贫的底线;人力资本对脱贫脆弱性具有显著的负向影响,引入... 详细信息

基于凉山彝区大型易地扶贫搬迁安置点1034户脱贫家庭的调研数据,实证分析人力资本对脱贫脆弱性的影响及作用机制。研究发现:部分脱贫户的脱贫较为脆弱,但能够守住不发生规模性返贫的底线;人力资本对脱贫脆弱性具有显著的负向影响,引入工具变量后其结论仍然成立,采用因变量替换法检验后其结论仍然稳健;人力资本对脱贫脆弱性的作用没有安置点类型差异,但有家庭收入差异;生计模式在人力资本对脱贫脆弱性的影响中起到中介作用。因此,建议高度重视脱贫脆弱性高风险的家庭,持续强化脱贫家庭人力资本的提升,创新推动脱贫家庭的生计模式转型。

关键词：脱贫脆弱性人力资本生计模式凉山彝区

Fragmented condensates of singly trapped dipolar Bose gases

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Science China(Physics,Mechanics & Astronomy) 2012年第9期55卷 1535-1540页

作者： LU HaiYan yi su State Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China

By employing the method of the multiconfigurational time-dependent Hartree for bosons,we investigate the ground state properties of a singly trapped dipolar gas of spinless *** show that the repulsive interactions favor the formation of the fragmented ground *** particular,we find the formation of the fragmented state is mainly due to the interaction energies associated with the one-and two-particle exchanges between *** also obtain the stability diagram of the system and find that the stability of the system is significantly enhanced by the appearance of the fragmentation.

关键词： fragmentation Bose-Einsein condensate dipole-dipole interation

Design and performance evaluation of a novel ranging signal based on an LEO satellite communication constellation

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Geo-Spatial Information Science 2023年第1期26卷 107-124页

作者： Jingfang su.Jia su.Qingwu yi Cailun Wu Weimin Hou School of Information Science and Engineering Hebei University of Science and TechnologyShijiazhuangChina The State Key Laboratory of Satellite Navigation System and Equipment Technology ShijiazhuangChina

Driven by improvements in satellite internet and Low Earth Orbit(LEO)navigation augmenta-tion,the integration of communication and navigation has become increasingly common,and further improving navigation capabilities based on communication constellations has become a significant *** the context of the existing Orthogonal Frequency Division Multiplexing(OFDM)communication systems,this paper proposes a new ranging signal design method based on an LEO satellite communication *** LEO Satellite Communication Constellation Block-type Pilot(LSCC-BPR)signal is su.erimposed on the com-munication signal in a block-type form and occupies some of the su.carriers of the OFDM signal for transmission,thus ensu.ing the continuity of the ranging pilot signal in the time and frequency *** estimation in the time and frequency domains is performed to obtain the relevant distance value,and the ranging accuracy and communication resource utilization rate are *** characterize the ranging performance,the Root Mean Square Error(RMSE)is selected as an evaluation *** show that when the number of pilots is 2048 and the Signal-to-Noise Ratio(SNR)is 0 dB,the ranging accuracy can reach 0.8 m,and the pilot occupies only 50%of the communication su.carriers,thus improving the utilization of communication resources and meeting the public demand for communication and location services.

关键词： Integration of communication and navigation LEO communication constellation ranging LEO navigation augmentation satellite internet