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一种用于过电压保护的ZnO阵列均能选片优化方法研究

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电瓷避雷器 2022年第1期 51-56页

作者：杨海运郜志宫艳朝苗俊杰吴伟丽奚涛国网邯郸供电公司河北邯郸056000 国网河北省电力公司石家庄050000 西安科技大学西安710054 安徽正广电电力技术有限公司合肥230088

氧化锌阀片因为具有优良的非线性而被广泛应用过电压保护装置,然而工程实践表明,过电压保护器常因个别氧化锌阀片能量不足、均能性差的问题而烧毁甚至爆炸,给电力系统运行造成危害,有鉴于此,提出了一种用于过电压保护器的高能氧化锌阀... 详细信息

氧化锌阀片因为具有优良的非线性而被广泛应用过电压保护装置,然而工程实践表明,过电压保护器常因个别氧化锌阀片能量不足、均能性差的问题而烧毁甚至爆炸,给电力系统运行造成危害,有鉴于此,提出了一种用于过电压保护器的高能氧化锌阀片的均能选片优化方法,首先,建立了ZnO阵列的阀片均能模型,并定义了均能系数指标,以衡量单个阀片承当能量的均衡性;接着,构建了ZnO配片优化模型,提出采用NSGA-Ⅲ算法进行求解,并提出优化流程,最后,通过实际配片需求对方法加以验证。本研究成果可为用于过电压保护器的ZnO规模化生产提供参考,具有一定的工程适用性。

关键词：高能氧化锌过电压均能 NSGA-Ⅲ 优化

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基于颜色通道融合特征的现勘图像分类算法

现代电子技术 2020年第4期43卷 67-72页

作者：刘颖张倩楠王富平雷研博公衍超杨凡超西安邮电大学图像与信息处理研究所陕西西安710121 电子信息现场勘验应用技术公安部重点实验室陕西西安710121 中国科学院西安光学精密机械研究所中国科学院光谱成像技术重点实验室陕西西安710119

针对单一特征难以精确地表达复杂图像内容的问题,提出基于颜色通道融合特征的现勘图像分类算法。首先,分别在H,S和V三个颜色通道上提取图像的LBP特征和GIST特征,并利用颜色空间信息进行加权融合;然后,将融合的LBP和GIST特征串联形成新... 详细信息

针对单一特征难以精确地表达复杂图像内容的问题,提出基于颜色通道融合特征的现勘图像分类算法。首先,分别在H,S和V三个颜色通道上提取图像的LBP特征和GIST特征,并利用颜色空间信息进行加权融合;然后,将融合的LBP和GIST特征串联形成新的特征描述向量,并用于训练分类器以实现精确地现勘图像分类。在现勘图像数据库上,大量实验结果显示提出的现勘图像分类算法优于基于单一特征的图像分类正确率。

关键词：现勘图像分类颜色通道特征提取特征融合训练分类器实验分析

计及MOA拟合特性的断线谐振过电压混沌性分析

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电瓷避雷器 2022年第6期 85-91页

为了避免断线谐振故障所产生的过电压对避雷器造成损伤,应用混沌数学理论,提出一种考虑雷器拟合特性的断线谐振过电压混沌性分析方法:首先,搭建避雷器在内断线谐振系统等值模型,并用状态方程描述断线谐振过程中避雷器的作用,从数学的角... 详细信息

为了避免断线谐振故障所产生的过电压对避雷器造成损伤,应用混沌数学理论,提出一种考虑雷器拟合特性的断线谐振过电压混沌性分析方法:首先,搭建避雷器在内断线谐振系统等值模型,并用状态方程描述断线谐振过程中避雷器的作用,从数学的角度解释了避雷器限制过电压的机理;其次,根据实际系统参数搭建了断线谐振系统仿真模型,并考虑氧化锌避雷器的伏安拟合特性加以仿真,得到断线后变压器高压进线侧的电压波形和相轨迹曲线,对比分析发现,避雷器并联在变压器高压进线侧可以钳制断线谐振过电压,不过避雷器不同的伏安特性段的抑制过电压效果有所不同,据此可以确定抑制过电压的避雷器流通电流阈值。研究成果可望为避雷器谐振过电压提供数学理论依据,也可为避雷器性能改善提供指导。

关键词：断线谐振过电压氧化锌避雷器分段模型

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基于深度学习的面部修复技术综述

计算机应用研究 2021年第1期38卷 9-14页

作者：刘颖佘建初公衍超卢津王富平林庆帆李莹华电子信息现场勘验应用技术公安部重点实验室西安710121 陕西省无线通信与信息处理技术国际合作研究中心西安710121 西安邮电大学图像与信息处理研究所西安710121 新加坡Silicon Vision有限公司新加坡787820

传统图像修复算法在修复区域涉及复杂非重复结构(如面部)时,不能准确捕捉到高级语义。近三年来基于深度学习的方法被应用于图像修复中,其修复结果的结构相似性较传统方法提高了10%以上。首先阐述了面部修复技术的研究发展历程,主要介绍... 详细信息

传统图像修复算法在修复区域涉及复杂非重复结构(如面部)时,不能准确捕捉到高级语义。近三年来基于深度学习的方法被应用于图像修复中,其修复结果的结构相似性较传统方法提高了10%以上。首先阐述了面部修复技术的研究发展历程,主要介绍了基于深度学习的面部修复算法,将其分为无监督和有监督两大类方法,在每一类中重点对近年来涌现的各种面部修复算法进行分析和总结;然后归纳了当前主流的六类图像数据集,以及算法性能评价指标;最后讨论了面部修复技术的未来研究方向。

关键词：面部图像修复深度学习生成对抗网络卷积神经网络

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现场勘验刀具图像特征描述与识别

西安邮电大学学报 2020年第1期25卷 49-55页

作者：刘颖李钊公衍超林庆帆王富平西安邮电大学通信与信息工程学院陕西西安710121 西安邮电大学电子信息现场勘验应用技术公安部重点实验室陕西西安710121 新加坡Siliconvision公司新加坡787820

针对人工录入现勘刀具图像耗时耗力、准确率低的问题,提出一种基于目标形状特征的现勘刀具图像识别算法。在分析现勘刀具图像特色数据基础上,总结现勘刀具图像的典型内容特性;利用基于结构森林的边缘检测和聚类的方法对目标定位和轮廓提... 详细信息

针对人工录入现勘刀具图像耗时耗力、准确率低的问题,提出一种基于目标形状特征的现勘刀具图像识别算法。在分析现勘刀具图像特色数据基础上,总结现勘刀具图像的典型内容特性;利用基于结构森林的边缘检测和聚类的方法对目标定位和轮廓提取,再结合包含目标轮廓的最小外接矩形给出刀尖角度的计算方法,并与长宽比、矩形度、圆形度构建识别刀目标的形状特征向量,将该特征向量输入支持向量机建立二分类模型,实现对现勘刀具图像的识别。实验结果表明,该算法性能明显优于其他特征提取算法,且对现勘刀具图像识别准确率达到94.61%,可有效表征刀具图像的内容。

关键词：犯罪现场勘验刀具图像识别形状特征支持向量机

Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders

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Neural Regeneration Research 2025年第5期20卷 1258-1276页

作者： Qing Qiu Mengting Yang Danfeng gong Haiying Liang Tingting Chen Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Jiangsu Province Key Laboratory of Inflammation and Molecular Drug Target NantongJiangsu ProvinceChina Department of Pharmacy Longyan First Affiliated Hospital of Fujian Medical UniversityLongyanFujian ProvinceChina

The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be u

关键词： astrocytes calcium channels central nervous system extracellular ion concentration microglia neurological disorders neurons potassium channels

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电力电容器的精准相控投切与过电压抑制

电气传动 2023年第8期53卷 9-14页

作者：宫艳朝杨海运苗俊杰郜志国网河北省电力有限公司邯郸供电分公司河北邯郸056035 国网河北省电力有限公司河北石家庄050011

并联电容器组在配电网的应用过程中,可以有效提高电能输送的效率和质量,但由于电力电容器投切方式的某些不合理因素,也会因其产生过电压,从而影响到电网的稳定性。研究分析电力电容器投切暂态状态,对于合闸暂态,通过建立电力电容器组合... 详细信息

并联电容器组在配电网的应用过程中,可以有效提高电能输送的效率和质量,但由于电力电容器投切方式的某些不合理因素,也会因其产生过电压,从而影响到电网的稳定性。研究分析电力电容器投切暂态状态,对于合闸暂态,通过建立电力电容器组合闸并联时的单相等效电路,简化电力电容器投切暂态过程;对于分闸暂态,计算断路器触头在电力电容器投切状态下产生的恢复电压。由储能电容器、开关电源、功率驱动输出接口以及电流/电压传感器接口等硬件组成同步开关控制器,实现电力电容器的过电压保护。为验证该方法的应用性能,开展实验分析,在合闸和分闸两种状态下采用同步控制器对电力电容器展开投切测试,三相电压波动具有对称规律性,且幅值变化较为平稳,有效抑制了电力电容器的过电压峰值。实验测试结果表明,所提方法的投切稳定性高、过电压抑制效果好。

关键词：电力电容器相控投切暂态分析同步控制器过电压抑制

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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing He Zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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