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跨脉冲传播的深度脉冲神经网络训练方法

计算机应用研究 2024年第7期41卷 2134-2140页

作者：曾建新陈云华李炜奇陈平华广东工业大学计算机学院广州510006

基于反向传播的脉冲神经网络(SNNs)的训练方法仍面临着诸多问题与挑战,包括脉冲发放过程不可微分、脉冲神经元具有复杂的时空动力过程等。此外,SNNs反向传播训练方法往往没有考虑误差信号在相邻脉冲间的关系,大大降低了网络模型的准确... 详细信息

基于反向传播的脉冲神经网络(SNNs)的训练方法仍面临着诸多问题与挑战,包括脉冲发放过程不可微分、脉冲神经元具有复杂的时空动力过程等。此外,SNNs反向传播训练方法往往没有考虑误差信号在相邻脉冲间的关系,大大降低了网络模型的准确性。为此,提出一种跨脉冲误差传播的深度脉冲神经网络训练方法(cross-spike error backpropagation,CSBP),将神经元的误差反向传播分成脉冲发放时间随突触后膜电位变化关系和相邻脉冲发放时刻点间的依赖关系两种依赖关系。其中,通过前者解决了脉冲不可微分的问题,通过后者明确了脉冲间的依赖关系,使得误差信号能跨脉冲传播,提升了生物合理性。此外,并对早期脉冲残差网络架构存在的模型表示能力不足问题进行研究,通过修改脉冲残余块的结构顺序,进一步提高了网络性能。实验结果表明,所提方法比基于脉冲时间的最优训练算法有着明显的提升,相同架构下,在CIFAR10数据集上提升2.98%,在DVS-CIFAR10数据集上提升2.26%。

关键词：脉冲神经网络脉冲时间依赖误差反向传播脉冲神经网络训练算法

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融合事件数据和图像帧的车辆目标检测

计算机应用 2024年第3期44卷 931-937页

作者：郑宇亮陈云华白伟杰陈平华广东工业大学计算机学院广州510006

将事件相机与传统相机结合进行车辆目标检测,既能解决传统相机在高动态范围下的过度曝光与曝光不足、运动模糊等问题,又能解决事件相机由于纹理信息缺失导致的检测精度不高的问题。现有融合算法往往存在计算复杂度高、特征信息丢失以及... 详细信息

将事件相机与传统相机结合进行车辆目标检测,既能解决传统相机在高动态范围下的过度曝光与曝光不足、运动模糊等问题,又能解决事件相机由于纹理信息缺失导致的检测精度不高的问题。现有融合算法往往存在计算复杂度高、特征信息丢失以及融合效果不佳等问题。为此,提出一种有效融合事件相机和传统相机的车辆目标检测算法。首先,提出一种基于事件计数(EF)和时间面(TS)的时空事件表示,将事件数据编码成事件帧;然后,提出一种基于通道和空间注意力机制的特征级融合模块(FCSA),对图像帧和事件帧进行特征级融合;最后,利用差分进化搜索算法优化先验框,以进一步提高车辆检测性能。此外,由于包含图像帧和事件数据的公开数据集较为缺乏,建立了一个车辆检测数据集MVSEC-CAR。实验结果表明,在公开数据集PKU-DDD17-CAR上,所提算法的平均精度均值(mAP)比次优的ADF(Attention fusion Detection Framework)提高了2.6个百分点,且获得了较高的帧率,有效提升了车辆目标检测的准确性和对光照的鲁棒性,验证了所提出的事件表示、特征融合和先验框优化算法的有效性。

关键词：事件相机车辆目标检测注意力机制特征融合事件表示

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济阳坳陷深层地热资源研究进展与下步展望

油气地质与采收率 2024年第4期31卷 196-206页

作者：杨永红杨万芹陈云华崔营滨中国石化胜利油田分公司勘探开发研究院山东东营257015

济阳坳陷地热资源分布范围广、资源潜力大,是胜利油区未来地热资源开发利用的重要方向。为科学、高效地开发利用济阳坳陷地热资源,系统梳理了关于济阳坳陷水热型和干热岩型地热资源的热储层、热盖层、热源等地热地质条件,分别计算了2类... 详细信息

济阳坳陷地热资源分布范围广、资源潜力大,是胜利油区未来地热资源开发利用的重要方向。为科学、高效地开发利用济阳坳陷地热资源,系统梳理了关于济阳坳陷水热型和干热岩型地热资源的热储层、热盖层、热源等地热地质条件,分别计算了2类地热资源的资源量,揭示其地热资源潜力。研究结果表明,济阳坳陷水热型地热资源主要赋存在馆陶组、东营组及下古生界等,其中馆陶组为水热型地热资源潜力最大的层系,分布广、资源量大,是下步重点勘探开发利用层系。济阳坳陷属于“冷壳热幔型”沉积盆地,具有较高的大地热流值,干热岩型地热资源热储层主要为太古宇的岩浆岩和变质岩,深部地幔热流是其主要热源,热储层分布面积大,温度均较高,其资源丰度为渤海湾盆地中最高。济阳坳陷地热资源丰富,为加快其开发利用步伐,建议水热型地热资源要加强地热资源与油气的关系及资源分区评价2项关键工作;干热岩型地热资源的勘探开发仍处于起步探索阶段,今后需要重点加强其热储层类型的选择与热源机制2个方面的研究。

关键词：地热资源干热岩热储层热源地温场济阳坳陷

Crossover effects of transition metal ions in high-voltage lithium metal batteries

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Nano Research 2023年第6期16卷 8417-8424页

作者： Wanxia Li Yulin Jie yunhua chen Ming Yang Yawei chen Xinpeng Li Youzhang Guo Xianhui Meng Ruiguo Cao Shuhong Jiao Hefei National Laboratory for Physical Science at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China NIO Incorporation Shanghai 201800China Science and Technology on Power Sources Laboratory Tianjin Institute of Power SourcesTianjin 300384China

Enhancing the cut-off voltage of high-nickel layered oxide cathodes is an efficient way to obtain higher energy density of lithiummetal batteries(LMBs).However,the phase transition of the cathode materials and the uncontrolled decomposition of the electrolytes at high voltage can lead to irreversible dissolution of transition metal ions,which might cause the crossover effects on the lithium metal ***,the mechanism and electrolyte dependence of the crossover effects for Li metal anodes are still ***,we investigate the crossover effects between LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)and Li-metal anode in two electrolyte *** ether-based electrolyte,its poor oxidation stability results in massive dissolution of transition metal ions,leading to dendrite growth on anode and rapid cells ***,ester-based electrolyte exhibits good electrochemical performances at 4.5 V with little crossover *** study provides an idea for electrolyte systems selection for high-voltage LMBs,and verifies that the crossover effect should not be neglected in LMBs.

关键词： crossover effects lithium-metal batteries high-nickel layered cathodes electrolyte systems dependence transition metals dissolution

Black phosphorus nanosheets-enabled DNA hydrogel integrating 3D-printed scaffold for promoting vascularized bone regeneration

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Bioactive Materials 2023年第3期21卷 97-109页

作者： Yali Miao yunhua chen Jinshui Luo Xiao Liu Qian Yang Xuetao Shi Yingjun Wang School of Materials Science and Engineering South China University of TechnologyGuangzhou510641China National Engineering Research Center for Tissue Restoration and Reconstruction South China University of TechnologyGuangzhou510006China Key Laboratory of Biomedical Engineering of Guangdong Province And Innovation Center for Tissue Restoration and ReconstructionSouth China University of TechnologyGuangzhou510006China Key Laboratory of Biomedical Materials and Engineering of the Ministry of Education South China University of TechnologyGuangzhou510006China

The classical 3D-printed scaffolds have attracted enormous interests in bone regeneration due to the customized structural and mechanical adaptability to bone ***,the pristine scaffolds still suffer from the absence of dynamic and bioactive microenvironment that is analogous to natural extracellular matrix(ECM)to regulate cell behaviour and promote tissue *** address this challenge,we develop a black phosphorus nanosheets-enabled dynamic DNA hydrogel to integrate with 3D-printed scaffold to build a bioactive gel-scaffold construct to achieve enhanced angiogenesis and bone *** black phosphorus nanosheets reinforce the mechanical strength of dynamic self-healable hydrogel and endow the gel-scaffold construct with preserved protein binding to achieve sustainable delivery of growth *** further explore the effects of this activated construct on both human umbilical vein endothelial cells(HUVECs)and mesenchymal stem cells(MSCs)as well as in a critical-sized rat cranial defect *** results confirm that the gel-scaffold construct is able to promote the growth of mature blood vessels as well as induce osteogenesis to promote new bone formation,indicating that the strategy of nano-enabled dynamic hydrogel integrated with 3D-printed scaffold holds great promise for bone tissue engineering.

关键词： DNA hydrogels 3D-printed scaffold Black phosphorus Vascularized bone regeneration

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湘阴县重金属污染耕地水稻钝化修复技术研究

矿产勘查 2024年第5期15卷 894-905页

作者：王雪平黄朝宇陈碧莹陈云华刘玉曹孟秋湖南省国土空间调查监测所湖南长沙410129 洞庭湖区生态环境遥感监测湖南省重点实验室湖南长沙410004

耕地重金属污染是影响国计民生的重要问题。本文以湘阴县重金属污染耕地为研究对象,参考前人土壤修复方面成果,提出了“矿物改性复合钝化—二次阻隔—增值修复”技术思路。选取蒙脱石等4种黏土矿物按不同比例混合,细磨(-400目)—超细磨(... 详细信息

耕地重金属污染是影响国计民生的重要问题。本文以湘阴县重金属污染耕地为研究对象,参考前人土壤修复方面成果,提出了“矿物改性复合钝化—二次阻隔—增值修复”技术思路。选取蒙脱石等4种黏土矿物按不同比例混合,细磨(-400目)—超细磨(-600目)配制出2种矿物改性复合钝化剂,采取以本次配制的2种矿物改性复合钝化剂为主,平行开展11种钝化处理,通过小区试验与大田示范同步进行。经验证,本次研制的改性复合钝化剂2+石灰+硅肥组合(GXFH-2+SH+SI)修复技术,能有效削减重金属污染耕地稻米Cd含量,并能有效增加稻米中有益元素Se含量,是一种成本低、效果好、操作简便的重金属污染耕地钝化修复技术,可推广应用。

关键词：重金属污染改性复合钝化修复小区试验大田示范

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工程认证背景下“葡萄酒加工工艺学”的构建与探索

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农产品加工 2024年第6期 112-113,117页

作者：朱磊陈芸华李兴革关琛贾健李艳青李志江黑龙江八一农垦大学食品学院黑龙江大庆163319

“葡萄酒加工工艺学”是一门兼具理论性和应用性的学科,集葡萄酒酿造原理及操作技能于一体,不断优化其课程教学体系是工程认证背景下改革实践的重要组成部分,也是提升食品学子在行业中的核心竞争力和社会贡献价值的有效措施。以黑龙江... 详细信息

“葡萄酒加工工艺学”是一门兼具理论性和应用性的学科,集葡萄酒酿造原理及操作技能于一体,不断优化其课程教学体系是工程认证背景下改革实践的重要组成部分,也是提升食品学子在行业中的核心竞争力和社会贡献价值的有效措施。以黑龙江八一农垦大学食品科学与工程专业的“葡萄酒加工工艺学”课程为研究对象,在原有基础上对课程体系从教学模式、教学手段和学习途径等方面进行构建与探索,以期推进食品科学与工程专业的“工程教育”实践活动,并在成果导向教育(OBE)模式下提高大学生工程能力满足新工科的适应度。

关键词：葡萄酒加工工艺学工程教育构建与探索实践教学

Modified filter for mean elements estimation with state jumping

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Journal of Systems Engineering and Electronics 2024年第4期35卷 999-1012页

作者： YU Yanjun YUE chengfei LI Huayi WU yunhua chen Xueqin Research Center of Satellite Technology Harbin Institute of TechnologyHarbin 150001China Institute of Space Science and Applied Technology Harbin Institute of Technology(Shenzhen)Shenzhen 518055China College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

To investigate the real-time mean orbital elements(MOEs)estimation problem under the influence of state jumping caused by non-fatal spacecraft collision or protective orbit trans-fer,a modified augmented square-root unscented Kalman filter(MASUKF)is *** MASUKF is composed of sigma points calculation,time update,modified state jumping detec-tion,and measurement *** with the filters used in the existing literature on MOEs estimation,it has three main ***,the state vector is augmented from six to nine by the added thrust acceleration terms,which makes the fil-ter additionally give the state-jumping-thrust-acceleration ***,the normalized innovation is used for state jumping detection to set detection threshold concisely and make the filter detect various state jumping with low ***,when sate jumping is detected,the covariance matrix inflation will be done,and then an extra time update process will be con-ducted at this time instance before measurement *** this way,the relatively large estimation error at the detection moment can significantly ***,typical simulations are per-formed to illustrated the effectiveness of the method.

关键词： unscented Kalman filter mean orbital elements(MOEs)estimation state jumping detection nonlinear system

Boosting cycling stability by regulating surface oxygen vacancies of LNMO by rapid calcination

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Nano Research 2024年第4期17卷 2671-2677页

作者： Haoran Jiang Cuihua Zeng Wei Zhu Jiawei Luo Zhedong Liu Jingchao Zhang Rui Liu yunhua Xu Yanan chen Wenbin Hu School of Materials Science and Engineering Tianjin UniversityTianjin 300072China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Spinel LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)has attracted intensive interest for lithium-ion battery due to its high voltage and high energy ***,severe capacity fade attributed to unstable surface structure has hampered its *** vacancies(OVs)tend to occur in the surface of the material and lead to surface structure reconstruction,which deteriorates the battery performance during electrochemical ***,we utilize high-temperature-shock(HTS)method to synthesize LNMO materials with fewer surface *** calcination drives lower surface OVs concentration,reducing the content of Mn^(3+)and surface reconstruction layers,which is beneficial to obtain a stable crystal *** LNMO material synthesized by HTS method delivers an initial capacity of 127 mAh·g^(-1) at 0.1 C and capacity retention of 81.6%after 300 cycles at 1 C,and exhibits excellent performance at low temperature.

关键词： ultrafast synthesis oxygen vacancy LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)cathode high-temperature-shock lithium-ion batteries