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基于SSVEP信号的相频特性分类算法研究

电子测量技术 2024年第5期47卷 188-198页

作者：丛佩超陈熙来肖宜轩李文彬刘俊杰张欣广西科技大学机械与汽车工程学院柳州545616

目前基于稳态视觉诱发电位(SSVEP)的脑-机接口在人机协作中受到广泛关注,现有面向SSVEP信号的相位与频率信息的深度学习分类方法,仍存在由于信息利用不充分导致的SSVEP信号分类效果较差等问题。而目前已出现多种分类算法用于解决上述问... 详细信息

目前基于稳态视觉诱发电位(SSVEP)的脑-机接口在人机协作中受到广泛关注,现有面向SSVEP信号的相位与频率信息的深度学习分类方法,仍存在由于信息利用不充分导致的SSVEP信号分类效果较差等问题。而目前已出现多种分类算法用于解决上述问题。本文基于迁移学习思想提出一种用于SSVEP信号分类的深度神经网络模型,将快速傅里叶变换后的复向量作为输入,对各个导联的实、虚部向量进行卷积,学习对应的相频特性。该模型分为两部分:第一部分利用所有被试者之间的统计共性获得相位和频率信息的全局相频特征模块;第二部分利用训练好的全局相频特征模块对局部相频特征模块进行初始化,通过局部相频特征模块的进一步强化学习对训练参数进行微调,以减少每个被试者之间的个体差异。在公开数据集BETA上进行测试,在时窗长度为1.5 s时,平均准确率和平均信息传输率分别为89.98%和71.80 bit/min。实验结果表明,与其他方法相比,本文的分类算法模型取得了较为不错的分类效果,所设计的全局、局部相频特征模块能够改善个体差异因素对分类结果的影响,为深入挖掘、利用SSVEP信号中的相位和频率信息提供了全新思路。

关键词：稳态视觉诱发电位迁移学习深度神经网络相频特性

锐钛矿相TiO_(2)纳米棒阵列的制备及其在钙钛矿太阳电池中的应用

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当代化工研究 2024年第7期 176-178页

作者：肖冠南朱峻杰梁桃华成都职业技术学院四川610041 材料腐蚀与防护四川省重点实验室四川643002 雅保四川新材料有限公司四川620860

在钙钛矿太阳电池中,定向生长的TiO_(2)纳米棒阵列具有可控的排列结构,能够为电子的传输提供有序的径向传输通道,从而改善电子在界面间的分离与传输。本文通过水热法成功制备了长度为400 nm、直径为65 nm、面密度为160μ·m^(-2)的锐钛... 详细信息

在钙钛矿太阳电池中,定向生长的TiO_(2)纳米棒阵列具有可控的排列结构,能够为电子的传输提供有序的径向传输通道,从而改善电子在界面间的分离与传输。本文通过水热法成功制备了长度为400 nm、直径为65 nm、面密度为160μ·m^(-2)的锐钛矿相TiO_(2)纳米棒阵列,使用摩尔比n(CH_(3)NH_(3)I):n(CH_(3)NH_(3)Br)=85:15的CH_(3)NH_(3)PbI_(3-x)Br_(x)薄膜作为钙钛矿光吸收层,spiro-OMeTAD作为空穴传输层组装了基于锐钛矿相TiO_(2)纳米棒阵列的钙钛矿太阳电池,研究了不同纳米棒阵列对钙钛矿太阳电池光伏性能的影响,结果表明,基于锐钛矿相TiO_(2)纳米棒阵列钙钛矿太阳电池在相对湿度为54%的空气环境下取得了14.35%的光电转换效率。

关键词：锐钛矿相TiO_(2)纳米棒阵列 ZnO纳米棒阵列钙钛矿太阳电池

Quantum Walk of Two Quantum Particles on One Dimensional System

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Journal of Quantum Information Science 2013年第4期3卷 138-142页

作者： Yongmei Zhang junjie xiao Dongsheng Hu Department of Applied Physics Nanjing University of Aeronau-tics and Astronautics Nanjing China

We study two particle quantum walks on one dimensional chain. Probability distribution of two particle quantum walks is dependent on the initial state, and symmetric quantum walk or asymmetric quantum walk is analogous to that of one particle quantum walk. The quantum correlation probability is much different from classical coincidence probability. The difference reflects quantum interference between two particles.

关键词： Quantum Walk Hadamard Operation Probability Distribution Correlation Probability

Zebrafish facilitates drug screening: potential of 3-deoxy-andrographoside from Chuanxinlian(Herba Andrographitis Paniculatae) as an anti-inflammatory agent

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Journal of Traditional Chinese Medicine 2022年第5期42卷 749-757页

作者： HE Xuemei xiao junjie FAN Chunlin LU Zibin CAO Huihui YU Linzhong ZHENG Yuanru LIU Junshan Third Level Research Laboratory of State Administration of Traditional Chinese Medicine School of Traditional Chinese MedicineSouthern Medical UniversityGuangzhou 510515China Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics Guangzhou 510515China Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research College of PharmacyJinan UniversityGuangzhou 510632China School of Pharmacy Guangdong Pharmaceutical universityGuangzhou 510006China Department of Pharmacy Zhujiang HospitalSouthern Medical UniversityGuangzhou 510515China

OBJECTIVE: To systematically evaluate the in vivo antiinflammatory potential of diterpene lactones from Chuanxinlian(Herba Andrographitis Paniculatae)(AP). METHODS: We firstly adopted zebrafish, a novel and ideal animal model for high-throughput drug screening, to investigate the in vivo anti-inflammatory activities of 17 diterpene lactones isolated from AP.RESULTS: The results showed that most of diterpene lactones displayed significant anti-inflammatory effects in lipopolysaccharide microinjection-, copper sulfate exposure-or tail transection-induced zebrafish inflammation models. Moreover, diterpene lactone 3-deoxy-andrographoside(AP-5) was firstly found to attenuate inflammatory responses, which was closely associated with the myeloid differentiation primary response 88/nuclear factor-kappa B and signal transducer and activator of transcription 3 pathways. CONCLUSION: Our research sheds light on the inestimable roles of zebrafish in high-throughput drug screening, elucidates the potent inhibitory effects of diterpene lactones against inflammation and indicates that AP-5 may serve as a potential alternative agent for the treatment of inflammatory diseases.

关键词： diterpenes lactones inflammation zebrafish myeloid differentiation factor 88 NF-kappa B STAT3 transcription factor

Giant quartic-phonon decay in PVD-grownα-MoO_(3) flakes

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Nano Research 2023年第1期16卷 1115-1122页

作者： Yongsong Wang xiao Guo Siwen You junjie Jiang Zihan Wang Fangping Ouyang Han Huang School of Physics and Electronics Hunan Key Laboratory of Nanophotonics and DevicesCentral South UniversityChangsha 410083China School of Physics and Electronics Hunan Key Laboratory of Super-microstructure and Ultrafast ProcessCentral South UniversityChangsha 410083China

Elementary excitations,such as in-plane anisotropic phonons and phonon polaritons(PhPs),inα-MoO_(3) play key roles in its outstanding physical properties like high carrier mobility and ultralow phonon thermal conductivity().Understanding the excitation mechanisms like phonon–phonon interactions is the most fundamental step to further applications.Here,we report on the systematic Raman investigations on phonon anisotropy and anharmonicity of representative Mo–O stretching vibration phonon modes(SVPMs)in physical vapor deposition(PVD)-grownα-MoO_(3) flakes.Polarizations of SVPMs verify the phonon anisotropy.The abnormal temperature dependence of SVPMs reveals that giant quartic-phonon decay dominates the phonon anharmonicity inα-MoO_(3).An ultrashort phonon lifetime of~0.34 ps gives evidence of theoretically predicted ultralow inα-MoO_(3).Our findings give deep insight into the phonon–phonon interactions inα-MoO_(3) and provide an indicator for its extreme thermal device applications.

关键词： layered materials synthesis phonon-phonon coupling anisotropy ultralow phonon thermal conductivity

A Study of Detecting Student Engagement Modes in an Online Learning Platform

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Frontiers of Education in China 2022年第1期17卷 23-45页

作者： xiao Rui LIU Qianhui SHANG junjie HUANG Win-bin Learning Science Laboratory Graduate School of EducationPeking UniversityBeijing 100871China Department of Information Management Peking UniversityBeijing 100871China

In this paper,we used the platform log data to extract three features(proportion of passive video time,proportion of active video time,and proportion of assignment time)aligning with different learning activities in the Interactive-Constructive-Active-Passive(ICAP)framework,and applied hierarchical clustering to detect student engagement modes.A total of 840 learning rounds were clustered into four categories of engagement:passive(n=80),active(n=366),constructive(n=75)and resting(n=319).The results showed that there were differences in the performance of the four engagement modes,and three types of learning status were identified based on the sequences of student engagement modes:difficult,balanced and easy.This study indicated that based on the ICAP framework,the online learning platform log data could be used to automatically detect different engagement modes of students,which could provide useful references for online learning analysis and personalized learning.

关键词： online learning platform online learning student engagement Interactive-Constructive-Active-Passive(ICAP)framework hierarchical clustering learning analytics log analysis

长期有机肥和化肥配施对黑土细菌群落特征和大豆产量的影响

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中国生态农业学报（中英文） 2024年第5期32卷 804-815页

作者：方海瑞刘俊杰陈雪丽姜宇刘株秀顾海东万书明肖洋黑龙江大学现代农业与生态环境学院哈尔滨150080 黑龙江省黑土保护利用研究院哈尔滨150086 中国科学院东北地理与农业生态研究所哈尔滨150081 黑龙江省农业科学院黑河分院黑河164300

有机物料还田是提高土壤微生物多样性和提升土壤质量的主要措施,但目前有机物料还田对黑土关键土壤微生物类群的影响及其与大豆产量间的关系尚未充分明确。本研究基于东北地区44年长期黑土定位试验,研究不同施肥措施与土壤理化性质、细... 详细信息

有机物料还田是提高土壤微生物多样性和提升土壤质量的主要措施,但目前有机物料还田对黑土关键土壤微生物类群的影响及其与大豆产量间的关系尚未充分明确。本研究基于东北地区44年长期黑土定位试验,研究不同施肥措施与土壤理化性质、细菌群落和大豆产能间的关联特征。结果表明:与无肥(NoF)对比,单施有机肥(M)和化肥配施有机肥(CFM)处理显著增加了土壤养分含量、微生物量碳和微生物量氮含量。化肥配施秸秆(CFS)处理的土壤细菌丰富度和多样性低于单施秸秆(S),而化肥配施有机肥(CFM)处理的土壤细菌丰富度和多样性高于单施有机肥处理(M)。相比于NoF,施肥导致富营养型细菌类群(r策略)与寡营养型细菌类群(K策略)的比值增加。长期秸秆还田(S和CFS)和施用化肥(CF)增加了细菌网络复杂性,而长期添加有机肥(M和CFM)降低了网络复杂性。结构方程模型表明土壤铵态氮、碳氮比、细菌网络结构复杂性和关键类群[硝化螺旋菌属(Nitrospira)与芽单胞菌属(Gemmatimonas)]丰度与大豆产量呈显著正相关关系。有机肥配施化肥(CFM)有利于提高关键功能微生物类群丰度、群落多样性和大豆产量。

关键词：黑土区施肥措施土壤理化性状细菌关键类群大豆产量

桂西北箭猪坡铅-锌-锑多金属矿床成因:来自闪锌矿微量、稀土元素及氢氧同位素的证据

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地质通报 2024年第2期43卷 246-257页

作者：何光武蔡明海胡鹏飞肖俊杰甘能俭朱敏杰吕堂安广西大学资源环境与材料学院广西南宁530004 广西壮族自治区二七二地质队广西南宁530033 中冶武勘工程技术有限公司湖北武汉430080 广西金土矿业评估咨询有限公司广西南宁530029

位于广西右江盆地北东侧的丹池成矿带是中国南方重要的有色金属矿集区,箭猪坡矿床是其南段五圩矿田中规模最大、成矿特征最具代表性的大型铅-锌-锑多金属矿床,由长期开采的脉状铅-锌-锑矿体和新发现的似层状锡多金属矿体组成。通过闪锌... 详细信息

位于广西右江盆地北东侧的丹池成矿带是中国南方重要的有色金属矿集区,箭猪坡矿床是其南段五圩矿田中规模最大、成矿特征最具代表性的大型铅-锌-锑多金属矿床,由长期开采的脉状铅-锌-锑矿体和新发现的似层状锡多金属矿体组成。通过闪锌矿的微量、稀土元素和氢-氧同位素分析,对比研究2类矿体成矿特征的差异,进一步探讨成矿流体来源及矿床成因类型。分析结果显示:箭猪坡矿床不同类型矿体中闪锌矿均相对富集Fe、Cu、Pb、Sn、Sb,亏损Ga、Ge、Co、Ni,与典型的岩浆热液型矿床相似。同时,似层状矿体中稀土元素总量(ΣREE=12.80×10^(-6)~44.31×10^(-6))高于脉状矿体(ΣREE=3.34×10^(-6)),具有明显的轻、重稀土元素分馏和Eu亏损。闪锌矿氢-氧同位素分析结果中,脉状矿体δD=-81.8‰~-69.2‰,δ^(18)O=2.1‰~5.2‰;似层状矿体δD=-109.4‰~-75.2‰,δ^(18)O=-4.0‰~4.0‰,指示2类矿体的成矿流体为岩浆热液与大气降水不同比例的混合流体。以上特征表明,箭猪坡矿床属于岩浆热液型铅锌矿床,脉状矿体和似层状矿体成矿物质(流体)主要来源于岩浆热液。

关键词：箭猪坡矿床闪锌矿微量元素稀土元素氢-氧同位素矿床成因广西

Natural polymers-enhanced double-network hydrogel as wearable flexible sensor with high mechanical strength and strain sensitivity

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Chinese Chemical Letters 2023年第6期34卷 178-183页

作者： Zhijie Zhao xiao Fan Shuoxuan Wang xiaoning Jin junjie Li Yuping Wei Yong Wang Department of Chemistry School of ScienceTianjin UniversityTianjin 300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300350China

Conductive hydrogels have shown great prospects as wearable flexible sensors.Nevertheless,it is still a challenge to construct hydrogel-based sensor with great mechanical strength and high strain sensitivity.Herein,an ion-conducting hydrogel was fabricated by introducing gelatin-dialdehydeβ-cyclodextrin(Gel-DACD)into polyvinyl alcohol-borax(PVA-borax)hydrogel network.Natural Gel-DACD network acted as mechanical deformation force through non-covalent cross-linking to endow the polyvinyl alcoholborax/gelatin-dialdehydeβ-cyclodextrin hydrogel(PGBCDH)with excellent mechanical stress(1.35 MPa),stretchability(400%),toughness(1.84 MJ/m3)and great fatigue resistance(200%strain for 100 cycles).Surprisingly,PGBCDH displayed good conductivity of 0.31 S/m after adding DACD to hydrogel network.As sensor,it showed rapid response(168 ms),high strain sensitivity(gage factor(GF)=8.57 in the strain range of 200%-250%)and reliable sensing stability(100%strain for 200 cycles).Importantly,PGBCDHbased sensor can accurately monitor complex body movements(knee,elbow,wrist and finger joints)and large-scale subtle movements(speech,swallow,breath and facial expressions).Thus,PGBCDH shows great potential for human monitoring with high precision.

关键词： Conductive hydrogel Double network Gelatin Dialdehydeβ-cyclodextrin Sensor