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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

A Novel Method for the Synthesis of Bioactive Benzimidazolyl-Phenoxyacetic Acid O-Acetylglucosyl Saccharide Esters

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Wuhan University Journal of Natural Sciences 2006年第2期11卷 419-422页

作者： chen Hong chen yunhua OU Chunyan HUANG Siqing Department of Applied Chemistry Guangdong Ocean University Zhanjiang 524088 Guangdong China Department of Chemistry Nanchang University Nanchang 330047 Jiangxi China

A novel method of synthesis of nitro or trifluoromethyl substituted benzimidazolyl phenoxyacetic acid O-acetylglucosyl saccharide esters by the reaction of O-acetylglucosyl bromide with substituted benzimidazolyl phenoxyacetic acid at room temperature was developed. 4 dimethylaminopyridine （DMAP） was used as catalyst, triethylamine （Et3N） was used as deacid reagent, three saccharide esters were synthesized in the system of DMAP/ Et3 N. The catalytic mechanism of DMAP/Et3N was discussed. The results show that DMAP is an effective catalyst, the yields can reach 50%. The test indicates that the title compounds show better antiplantviral activity.

关键词： Saccharide Estersbenzimidazolyl-phenoxyacetic acid O-acetylglucosyl saecharide ester antiplantviral activity DMAP/Et3N

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

Quaternary primary productivity in Porcupine Seabight,NE North Atlantic

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Science China Earth Sciences 2012年第2期55卷 306-314页

作者： LI XiangHui Akihiro KANO chen yunhua Chiduru TAKASHIMA XU WenLi XU BaoLiang WANG RuiJian State Key Laboratory of Enhanced Oil Recovery Institute of Petroleum Exploration&DevelopmentChina National Petroleum CorporationBeijing 100083China Graduate School of Social and Cultural Studies Kyushu University4-2-1 RopponmatsuFukuoka 810-8560Japan School of Earth Sciences and Engineering Nanjing UniversityNanjing 210093China Geological Science Research Institute of Shengli Oilfield SINOPECDongying 257015China Environment Studies Faculty of Culture and EducationSaga University1 Honjo-machiSaga 840-8502Japan Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Sichuan Research Centre Bureau of Geophysical Prospecting of China National Petroleum CorporationChengdu 610051China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China

Biogenic opal and calcium carbonate contents in the Quaternary fine-grained sediments in the deep sea coral mound area (Hole U1317E and Hole U1318B drilled by IODP Expedition 307) in Porcupine Seabight, southwest off Ireland, were measured to estimate the primary productivity (Pp) of the surface seawater in NE Atlantic. The results from the two holes commonly show relatively high Pp values of 10-30 g cm-2 ky-1, having stratigraphic cyclicity reversely correlated with the δ13C profile. The high Pp could be attributed to the oceanic setting controlled by the Eastern North Atlantic (Central) Water and Shelf Edge Current, which have been strongly influenced by the obliquity forcing of the Milankovitch cycle. A positive covariance was observed between high Pp and the mound development in U1317E, implying that the organic matter was the principal food source for the mound coral community. It is proposed that the pelagic marl matrix of the mound sediments provides information of the surface water productivity that is useful for reconstructing the paleoceanography and the paleoclimate in the NW Atlantic.

关键词： primary productivity biogenic opal calcium carbonate Quaternary IODP 307 Porcupine Seabight North Atlantic

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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会泽县羊常见疾病防控存在的问题及其对策

南方农业 2024年第15期18卷 254-256页

作者：孙柱明王金海陈云华胡成仓会泽县者海镇农业农村综合服务中心云南会泽654211 会泽县大海草原保护开发管理所云南会泽654200

云南省会泽县积极发展山地畜牧业,全力推进养殖业的规模化、标准化、产业化发展,取得了良好成效。为降低疾病风险,保障会泽县羊养殖业的健康可持续发展,重点分析会泽县羊常见疾病防控存在的疫病流行监测体系有待完善、养殖环境卫生管理... 详细信息

云南省会泽县积极发展山地畜牧业,全力推进养殖业的规模化、标准化、产业化发展,取得了良好成效。为降低疾病风险,保障会泽县羊养殖业的健康可持续发展,重点分析会泽县羊常见疾病防控存在的疫病流行监测体系有待完善、养殖环境卫生管理欠佳、疾病诊断与治疗技术水平不足、羊群抗病力亟待提升等问题,提出构建精准疫情监测与快速响应机制、实施标准化养殖场环境卫生管控措施、提高疾病诊疗技术专业化水平、加强羊群免疫力建设与疫苗接种管理等对策。

关键词：羊疾病防控问题对策云南省会泽县

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会泽县牛疾病特点及防治对策

南方农业 2024年第18期18卷 141-143页

作者：孙柱明王金海陈云华胡成仓会泽县者海镇农业农村综合服务中心云南会泽654211 会泽县大海草原保护开发管理所云南会泽654200

云南省会泽县是我国重要的牛产区,但近年来该地牛疾病频发,严重影响了当地牛产业的健康发展。为有效控制牛疾病,分析会泽县牛疾病流行特点及存在的问题,并针对问题提出扩大牛传染性胃肠炎疫苗接种覆盖面、优化牛白细胞减少症监测和风险... 详细信息

云南省会泽县是我国重要的牛产区,但近年来该地牛疾病频发,严重影响了当地牛产业的健康发展。为有效控制牛疾病,分析会泽县牛疾病流行特点及存在的问题,并针对问题提出扩大牛传染性胃肠炎疫苗接种覆盖面、优化牛白细胞减少症监测和风险管控策略、开发牛痘病毒快速诊断试剂盒及推广牛结核病短周期治疗方案等措施。

关键词：牛疾病治疗难点防治措施云南省会泽县

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