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A Review of Computing with Spiking Neural Networks

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Computers, Materials & Continua 2024年第3期78卷 2909-2939页

作者： Jiadong Wu Yinan Wang zhiwei li Lun Lu Qingjiang li College of Electronic Science and Technology National University of Defense TechnologyChangsha410073China

Artificial neural networks(ANNs)have led to landmark changes in many fields,but they still differ significantly fromthemechanisms of real biological neural networks and face problems such as high computing costs,excessive computing power,and so *** neural networks(SNNs)provide a new approach combined with brain-like science to improve the computational energy efficiency,computational architecture,and biological credibility of current deep learning *** the early stage of development,its poor performance hindered the application of SNNs in real-world *** recent years,SNNs have made great progress in computational performance and practicability compared with the earlier research results,and are continuously producing significant *** there are already many pieces of literature on SNNs,there is still a lack of comprehensive review on SNNs from the perspective of improving performance and practicality as well as incorporating the latest research *** from this issue,this paper elaborates on SNNs along the complete usage process of SNNs including network construction,data processing,model training,development,and deployment,aiming to provide more comprehensive and practical guidance to promote the development of ***,the connotation and development status of SNNcomputing is reviewed systematically and comprehensively from four aspects:composition structure,data set,learning algorithm,software/hardware development *** the development characteristics of SNNs in intelligent computing are summarized,the current challenges of SNNs are discussed and the future development directions are also *** research shows that in the fields of machine learning and intelligent computing,SNNs have comparable network scale and performance to ANNs and the ability to challenge large datasets and a variety of *** advantages of SNNs over ANNs in terms of energy efficiency and spatial-temporal data processing

关键词： Spiking neural networks neural networks brain-like computing artificial intelligence learning algorithm

Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface

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International Journal of Extreme Manufacturing 2024年第2期6卷 449-467页

作者： zhiwei li Jianfu Zhang Zhongpeng Zheng Pingfa Feng Dingwen Yu Jianjian Wang State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipments and Control Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Division of Advanced Manufacturing Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055People’s Republic of China

High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon ***,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing *** study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect *** conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving *** tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material *** to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling *** one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of ***,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process ***,surface texturing tests are performed on copper to verify the efficacy of *** micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on *** with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 *** experimental results also verify the accuracy of the developed surface generation model of ***,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed.

关键词： metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation

A novel strategy of tannery sludge disposal–converting into biochar and reusing for Cr(Ⅵ)removal from tannery wastewater

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Journal of Environmental Sciences 2024年第4期138卷 637-649页

作者： zhiwei li Di Yu Xingdong Wang Xuejiao liu Zhen Xu Yin Wang CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control CAS Haixi Industrial Technology Innovation Center in BeilunNingbo 315830China Key Laboratory of Urban Environment and Health Ningbo Observatio

Tannery sludge with high chromium content has been identified as hazardous solid waste due to its potential toxic *** safety disposal and valorization of the tannery sludge remains a *** this study,the chromium stabilization mechanism was systematically investigated during chromium-rich tannery sludge was converted to biochar and the removal performance of the sludge biochar(SBC)for Cr(Ⅵ)from tannery wastewater was also *** results showed that increase in pyrolysis temperature was conductive to the stabilization of Cr and significant reduction of the proportion of Cr(Ⅵ)in *** was confirmed that the stabilization of chromium mainly was attributed to the embedding of chromium in the C matrix and the transformation of the chromium-containing substances from the amorphous Cr(OH)_(3)to the crystalline state,such as(FeMg)Cr_(2)O_(5).The biochar presented high adsorption capacity of Cr(Ⅵ)at low pH and the maximal theoretical adsorption capacity of SBC produced at 800°C can reach 352 mg Cr(Ⅵ)/g,the process of which can be well expressed by Langmuir adsorption isotherm and pseudo second order *** electrostatic effect and reduction reaction were dominantly responsible for the Cr(Ⅵ)adsorption by ***,this study provided a novel strategy for the harmless disposal and resource utilization for the solid waste containing chromium in leather industry.

关键词： Chromium-rich tannery sludge Pyrolysis Biochar Stabilizationmechanisms Cr(Ⅵ)adsorption

Role of 5-hydroxytryptamine type 3 receptors in the regulation of anxiety reactions

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 23-37页

作者： Yinan DU zhiwei li Yukui ZHAO Jing HAN Weiping HU Zhiqiang liU MOE Key Laboratory of Modern Teaching Technology Shaanxi Normal UniversityXi’an710062China

5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor *** the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety *** have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and *** provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)***,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R ***,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.

关键词： 5-Hydroxytryptamine type 3 receptor(5-HT_(3)R) Anxiety Medial prefrontal cortex Amygdala Hippocampus Periaqueductal gray

Co and postseismic fault slip models of the 2022 MW6.7 Menyuan earthquake reveal conjugated faulting tectonics at the central section of the Lenglongling fault

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Earthquake Science 2024年第4期37卷 277-303页

作者： Zilong He Wenbin Xu zhiwei li Lei Xie Guangcai Feng Nan Fang Xiaoge liu Kai Sun Zhidan Chen Zhihui Zhu School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Central South UniversityChangsha 410083China School of Civil Engineering Central South UniversityChangsha 410083China

The 2022 M_(W)6.7 Menyuan earthquake ruptured the western end of the Tianzhu seismic gap,providing an opportunity to study the regional seismogenic characteristics and seismic *** we use interferometric synthetic aperture radar(InSAR)and seismic data to study the mainshock rupture,early afterslip and the second largest aftershock of the 2022 Menyuan earthquake *** modeling results show that the mainshock ruptured the Lenglongling fault and the Tuolaishan fault with a maximum slip of~3 *** postseismic transient deformation occurred at the center of the Lenglongling *** afterslip modeling reveals that the majority of afterslip occurred in the deeper part of the Lenglongling fault.A high-angle conjugated faulting event is found at the middle section of the Lenglongling *** use the stress inversion to investigate the possible triggering mechanism of the conjugated rupture *** results indicate the maximum principal stress direction is in~222°,forming a~22°angle between the conjugated fault of second largest aftershock and the *** calculated normal stress changes indicate the region is within a pull-apart stress field,which favors such a conjugated rupturing *** study will help understand the rupture behavior of such kind of conjugated fault in other regions.

关键词： coseismic displacement and slip postseismic deformation and afterslip conjugate rupture coulomb stress change stress inversion

Electronic Correlation and Pseudogap-like Behavior of High-Temperature Superconductor La_(3)Ni_(2)O_(7)

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Chinese Physics Letters 2024年第8期41卷 82-93页

作者： Yidian li Xian Du Yantao Cao Cuiying Pei Mingxin Zhang Wenxuan Zhao Kaiyi Zhai Runzhe Xu Zhongkai liu zhiwei li Jinkui Zhao Gang li Yanpeng Qi Hanjie Guo Yulin Chen Lexian Yang State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Key Lab for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China Songshan Lake Materials Laboratory Dongguan 523808China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China ShanghaiTech Laboratory for Topological Physics Shanghai 200031China Shanghai Key Laboratory of High-Resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210China Department of Physics Clarendon LaboratoryUniversity of OxfordParks RoadOxford OX13PUUK Frontier Science Center for Quantum Information Beijing 100084China

High-temperature superconductivity(HTSC)remains one of the most challenging and fascinating mysteries in condensed matter ***,superconductivity with transition temperature exceeding liquid-nitrogen temperature is discovered in La_(3)Ni_(2)O_(7) at high pressure,which provides a new platform to explore the unconventional *** this work,using high-resolution angle-resolved photoemission spectroscopy and ab initio calculation,we systematically investigate the electronic structures of La_(3)Ni_(2)O_(7) at ambient *** experiments are in nice agreement with ab initio calculations after considering an orbital-dependent band renormalization *** strong electron correlation effect pushes a flat band of d_(z^(2))𝑧2 orbital component below the Fermi level(E_(F)),which is predicted to locate right at E_(F) under high ***,the d_(x^(2)−y^(2)) band shows pseudogap-like behavior with suppressed spectral weight and diminished quasiparticle peak near E_(F).Our findings provide important insights into the electronic structure of La_(3)Ni_(2)O_(7),which will shed light on understanding of the unconventional superconductivity in nickelates.

关键词： effect. superconductivity orbital

基于CT图像的水泥稳定RAP材料细观结构研究

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材料导报 2024年第1期38卷 66-71页

作者：阳虎单丽岩李志伟哈尔滨工业大学交通科学与工程学院哈尔滨150090

研究沥青混合料回收料(RAP)掺加对混合料组成与结构特性的影响,可为其应用在路面结构层以及材料参数设计提供理论支撑。基于X-ray CT与图像处理技术,提出了一种可区分新旧集料的冷再生混合料细观结构识别方法,分析了RAP团粒、旧集料与... 详细信息

研究沥青混合料回收料(RAP)掺加对混合料组成与结构特性的影响,可为其应用在路面结构层以及材料参数设计提供理论支撑。基于X-ray CT与图像处理技术,提出了一种可区分新旧集料的冷再生混合料细观结构识别方法,分析了RAP团粒、旧集料与新集料的细观特征的差异,研究了RAP的掺加对水泥稳定材料细观结构的影响。结果表明:提出的细观结构识别方法可准确识别水泥稳定RAP材料断面图像中的空隙、砂浆、新集料与旧集料四类区域,完整地保留新旧集料的原始轮廓、大小与形状等信息;RAP团粒中分布较多初始微细裂缝,且旧集料扁平比与棱角性系数均大于新集料;RAP的掺加一方面增加了再生混合料中体积小于0.01 mm3的微空隙与大于100 mm3的大空隙数量,导致材料的密实度降低;另一方面也增加了材料的沥青砂浆含量,提高了再生混合料的平均砂浆膜厚度,使混合料骨架内部力传导更均匀;提高水泥稳定RAP材料中石屑与碎石比例,可使材料的平均空隙体积减小、平均砂浆膜厚度增大,从而改善再生混合料的骨架填充状态。

关键词： RAP 水泥稳定材料 X-ray CT 细观结构冷再生技术

以明式家具为例的中国传统纹样数字化建构策略研究

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包装工程 2024年第12期45卷 482-490页

作者：李至惟张森南京艺术学院南京210013 南京工业职业技术大学南京210013

目的探索数字信息时代背景下,中国传统纹样数字化建构的策略,以此更好地传承和发展具有数千年演变历史的中国传统纹样。方法通过逻辑推演推导出无序纹样的数字化建构策略。通过分析冰裂纹、云雷纹、曲水纹的数字化建构过程,推导出宏观... 详细信息

目的探索数字信息时代背景下,中国传统纹样数字化建构的策略,以此更好地传承和发展具有数千年演变历史的中国传统纹样。方法通过逻辑推演推导出无序纹样的数字化建构策略。通过分析冰裂纹、云雷纹、曲水纹的数字化建构过程,推导出宏观视角下有序纹样的数字化建构策略,再以明式家具卷云纹样牙头作为细分案例,通过对它的数字化建构实践来检验建构策略的可行性。结果得到宏观视角下中国传统纹样的数字化建构策略,包括建构的技术、方法、发展方向等。结论无序纹样的数字化建构策略包括数字化采集与记录、图像处理与重构、矢量化处理、模式设计与创新、应用与传承五个步骤;有序纹样的数字化建构可对纹样形状进行调节,建构策略包括数字化采集与整理、图形结构研究、数学模型建构、模型优化、应用适应性拓展五个步骤。

关键词：中国传统纹样数字化建构明式家具设计策略

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基于YOLO v7-ST-ASFF的复杂果园环境下苹果成熟度检测方法

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农业机械学报 2024年第6期55卷 219-228页

作者：苗荣慧李港澳黄宗宝李志伟杜慧玲山西农业大学信息科学与工程学院太谷030801 山西农业大学农业工程学院太谷030801 山西农业大学基础部太谷030801

针对复杂果园环境下目标检测算法参数量大、鲁棒性差等问题,本文提出一种改进的YOLO v7网络模型用于苹果成熟度(未成熟、半成熟、成熟)检测。以YOLO v7为基线网络,在特征提取结构中引入窗口多头自注意力机制(Swin transformer,ST),极大... 详细信息

针对复杂果园环境下目标检测算法参数量大、鲁棒性差等问题,本文提出一种改进的YOLO v7网络模型用于苹果成熟度(未成熟、半成熟、成熟)检测。以YOLO v7为基线网络,在特征提取结构中引入窗口多头自注意力机制(Swin transformer,ST),极大地降低网络参数量与计算量;为提高模型对远景图像中小目标的检测能力,在特征融合结构中引入自适应空间特征融合(Adaptively spatial feature fusion,ASFF)模块优化Head部分,有效利用图像的浅层特征和深层特征,加强特征尺度不变性;采用WIoU(Wise intersection over union)代替原始CIoU(Complete intersection over union)损失函数,在提高检测准确率的同时加快模型收敛速度。试验结果表明,本文改进的YOLO v7-ST-ASFF模型在苹果图像测试集上的检测速度和准确率均有显著提高,不同成熟度检测精确率、召回率和平均精度均值可达92.5%、84.2%和93.6%,均优于Faster R-CNN、SSD、YOLO v3、YOLO v5、YOLO v7以及YOLO v8目标检测模型;针对多目标、单目标、顺光、逆光、远景、近景以及套袋、未套袋苹果目标的检测效果都较好;本文网络模型内存占用量为53.4MB,模型平均检测时间(Average detection time,ADT)为***,均优于其他目标检测模型。改进的YOLO v7-ST-ASFF模型能够满足复杂果园环境下苹果目标的检测,可为果蔬机器人自动化采摘提供技术支撑。

关键词：苹果成熟度检测复杂果园环境 YOLO v7 窗口多头自注意力机制 ASFF

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