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Pressure tuning of the anomalous Hall effect in the kagome superconductor CsV_(3)Sb_(5)

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Chinese Physics B 2022年第1期31卷 31-36页

作者： Fang-Hang Yu Xi-Kai Wen zhi-gang gui Tao Wu Zhenyu Wang Zi-Ji Xiang Jianjun Ying Xianhui Chen Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics and CAS Key Laboratory of Strongly-coupled Quantum Matter PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics Hefei 230026China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

Controlling the anomalous Hall effect(AHE)inspires potential applications of quantum materials in the next generation of *** recently discovered quasi-2D kagome superconductor CsV_(3)Sb_(5) exhibits large AHE accompanying with the charge-density-wave(CDW)order which provides us an ideal platform to study the interplay among nontrivial band topology,CDW,and unconventional ***,we systematically investigated the pressure effect of the AHE in CsV_(3)Sb_(5).Our high-pressure transport measurements confirm the concurrence of AHE and CDW in the compressed CsV_(3)Sb_(5).Remarkably,distinct from the negative AHE at ambient pressure,a positive anomalous Hall resistivity sets in below 35 K with pressure around 0.75 GPa,which can be attributed to the Fermi surface reconstruction and/or Fermi energy shift in the new CDW phase under *** work indicates that the anomalous Hall effect in CsV_(3)Sb_(5) is tunable and highly related to the band structure.

关键词： anomalous Hall effect(AHE) charge-density-wave(CDW) kagome superconductor pressure effect

Traffic safety helmet wear detection based on improved YOLOv5 network

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Optoelectronics Letters 2025年第1期21卷 35-42页

作者： gui Dongdong SUN Bo College of Software Southeast University Quanzhou Equipment Research Centre Haixi Institute Chinese Academy of Sciences

Aiming at the problem that the current traffic safety helmet detection model can't balance the accuracy of detection with the size of the model and the poor generalization of the model, a method based on improving you only look once version 5(YOLOv5) is proposed. By incorporating the lightweight Ghost Net module into the YOLOv5 backbone network, we effectively reduce the model size. The addition of the receptive fields block(RFB) module enhances feature extraction and improves the feature acquisition capability of the lightweight model. Subsequently, the high-performance lightweight convolution, GSConv, is integrated into the neck structure for further model size compression. Moreover, the baseline model's loss function is substituted with efficient insertion over union(EIoU), accelerating network convergence and enhancing detection precision. Experimental results corroborate the effectiveness of this improved algorithm in real-world traffic scenarios.

关键词： Traffic control

Offload Strategy for Edge Computing in Satellite Networks Based on Software Defined Network

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Computers, Materials & Continua 2025年第1期82卷 863-879页

作者： zhiguo Liu Yuqing gui Lin Wang Yingru Jiang Communication and Network Laboratory Dalian UniversityDalian116622China College of Environment and Chemical Engineering Dalian UniversityDalian116622China

Satellite edge computing has garnered significant attention from researchers;however,processing a large volume of tasks within multi-node satellite networks still poses considerable *** sharp increase in user demand for latency-sensitive tasks has inevitably led to offloading bottlenecks and insufficient computational capacity on individual satellite edge servers,making it necessary to implement effective task offloading scheduling to enhance user *** this paper,we propose a priority-based task scheduling strategy based on a Software-Defined Network(SDN)framework for satellite-terrestrial integrated networks,which clarifies the execution order of tasks based on their ***,we apply a Dueling-Double Deep Q-Network(DDQN)algorithm enhanced with prioritized experience replay to derive a computation offloading strategy,improving the experience replay mechanism within the Dueling-DDQN ***,we utilize the Deep Deterministic Policy Gradient(DDPG)algorithm to determine the optimal resource allocation strategy to reduce the processing latency of *** results demonstrate that the proposed d3-DDPG algorithm outperforms other approaches,effectively reducing task processing latency and thus improving user experience and system efficiency.

关键词： Satellite network edge computing task scheduling computing offloading

金融发展、融资渠道与企业研发投入——基于中国高科技上市公司面板数据的实证研究

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资源开发与市场 2017年第11期33卷 1371-1377页

作者：陈志刚方进桂立武汉大学中国中部发展研究院湖北武汉430072

以中国高科技上市公司2009—2015年面板数据为样本,就金融发展和融资渠道对我国企业研发投入的影响进行了实证研究。研究发现:(1)总体上看,我国高科技上市公司企业研发活动存在融资约束问题,金融发展可提高企业研发投入,且企业研发投入... 详细信息

以中国高科技上市公司2009—2015年面板数据为样本,就金融发展和融资渠道对我国企业研发投入的影响进行了实证研究。研究发现:(1)总体上看,我国高科技上市公司企业研发活动存在融资约束问题,金融发展可提高企业研发投入,且企业研发投入不依赖于股权融资而依赖于商业信用融资。(2)分地区看,东部地区的金融发展提高了企业研发投入,而中西部地区的金融发展与企业研发投入不相关。在东部和中西部地区,股权融资会降低企业研发投入,即在东部和中西部地区企业研发投入不依赖于股权融资。(3)从所有权性质看,在国有控股公司中,金融发展与企业研发投入不存在显著关系,国有企业的研发投入依赖于商业信用融资;但在私人控股公司中,金融发展会显著提高企业研发投入,非国有企业的研发投入不依赖于股权融资。从缓解企业研发投入的融资约束、增强高科技上市公司的企业研发投入角度,提出相关政策建议。

关键词：金融发展融资渠道研发投入融资约束商业信用融资股权融资

Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua Zhang Lingjing Chen Huatian Shi Yue Wei gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

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民办二级学院“线性代数”课程的现状与改革

苏州市职业大学学报 2011年第2期22卷 59-61页

作者：黄志刚孙桂荣苏州科技学院数理学院江苏苏州215009

民办二级学院的线性代数教学面临着学生的学习习惯、态度和基础较差,以及教材不适用、教学方法较传统等问题,在实际教学中,需要针对民办学院学生的特点,改革教学方法和手段,通过编写新教学大纲与教材,结合数学建模、实验,利用计算机辅... 详细信息

民办二级学院的线性代数教学面临着学生的学习习惯、态度和基础较差,以及教材不适用、教学方法较传统等问题,在实际教学中,需要针对民办学院学生的特点,改革教学方法和手段,通过编写新教学大纲与教材,结合数学建模、实验,利用计算机辅助教学,实现教学内容的改革,并对考核方式进行改革,以提高教学效果,培养学生的学习能力和实践能力.

关键词：线性代数教学改革民办学院

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一种高效节能的无线传感器网络分簇路由算法

传感器与微系统 2018年第9期37卷 139-141页

作者：施志刚李桂娟李亮张持健安徽师范大学物理与电子信息学院安徽芜湖241000

为了解决低能量自适应聚簇分层(LEACH)算法中簇头分布不均匀、选举不合理以及路由方式单一的不足,提出了一种高效节能的无线传感器网络(WSNs)分簇路由算法(ECRAW)。运用遗传算法和引力对簇的形成进行改进;综合考虑节点的剩余能量、节点... 详细信息

为了解决低能量自适应聚簇分层(LEACH)算法中簇头分布不均匀、选举不合理以及路由方式单一的不足,提出了一种高效节能的无线传感器网络(WSNs)分簇路由算法(ECRAW)。运用遗传算法和引力对簇的形成进行改进;综合考虑节点的剩余能量、节点与基站(BS)以及节点与簇中心之间的距离来优化簇头的选举;通过通信代价函数建立簇头与基站的多跳通信。仿真结果表明:相比于LEACH和能耗比较的LEACH(LEACH-EC)算法,ECRAW算法明显降低了网络能耗,均衡了节点能量消耗,延长了网络生存周期。

关键词：无线传感器网络低能量自适应聚簇分层遗传算法引力多跳

Hard-core Hall tube in superconducting circuits

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Chinese Physics B 2022年第8期31卷 226-233页

作者： Xin Guan gang Chen Jing Pan zhi-Guo gui Department of Materials and Chemical Engineering Taiyuan UniversityTaiyuan 030032China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China

The Hall tube as a minimum model to simulate the integer quantum Hall effect is essential for exploring topological physics, while it has not been constructed in the recent developing successfully experiments on superconducting *** this work, we propose a feasible experiment scheme using three legs superconducting circuits with transmon qubits to realize a Hall tube. Then we first investigate its topological properties. Since the time–reversal, particle–hole, and chiral symmetries are all broken for the system, the Hall tube belongs to the A class of the Altland–Zirnbauer *** obtain the corresponding topological phase transition both numerically and analytically. Since the chirality is a key character of the quantum Hall effect, we secondly investigate the chiral physics in the Hall tube. We find the topological protected chiral edge currents and discuss its robustness. Finally, we give the possible experimental observations of the topological state and topological protected chiral edge currents.

关键词： Hall tube superconducting circuits topological phase transition chiral edge currents