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International Journal of Intelligent Computing and Cybernetics 2023年第1期16卷 46-67页

作者： Tian-Jian Luo College of Computer and Cyber Security Fujian Normal UniversityFuzhouChina Digital Fujian Internet-of-Thing laboratory of Environmental Monitoring Fujian Normal UniversityFuzhouChina

Purpose-Steady-state visual evoked potential(SSVEP)has been widely used in the application of electroencephalogram(EEG)based non-invasive brain computer interface(BCI)due to its characteristics of high accuracy and information transfer rate(ITR).To recognize the SSVEP components in collected EEG trials,a lot of recognition algorithms based on template matching of training trials have been proposed and applied in recent *** this paper,a comparative survey of SSVEP recognition algorithms based on template matching of training trails has been ***/methodology/approach-To survey and compare the recently proposed recognition algorithms for SSVEP,this paper regarded the conventional canonical correlated analysis(CCA)as the baseline,and selected individual template CCA(ITCCA),multi-set CCA(MsetCCA),task related component analysis(TRCA),latent common source extraction(LCSE)and a sum of squared correlation(SSCOR)for ***-For the horizontal comparative of the six surveyed recognition algorithms,this paper adopted the“tsinghua JFPM-SSVEP”data set and compared the average recognition performance on such data *** comparative contents including:recognition accuracy,ITR,correlated coefficient and R-square values under different time duration of the SSVEP stimulus *** on the optimal time duration of stimulus presentation,the author has also compared the efficiency of the six compared *** measure the influence of different parameters,the number of training trials,the number of electrodes and the usage of filter bank preprocessing were compared in the ablation ***/value-Based on the comparative results,this paper analyzed the advantages and disadvantages of the six compared SSVEP recognition algorithms by considering application scenes,realtime and computational ***,the author gives the algorithms selection range for the recognition of real-world online SSVEP-BCI.

关键词： Non-invasive brain-computer interface EEG signals Template matching of training trials Steadystate visual evoked potential Optimal projection vector

Hydrogenation of molecular oxygen to hydroperoxyl： An alternative pathway for O2 activation on nanogold catalysts

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Nano Research 2015年第11期8卷 3737-3748页

作者： Chun-Ran Chang Zheng-Qing Huang Jun Li School of Chemical Engineering and Technology Xi'an Jiaotong University Xi'an 710049 China Department of Chemistry and Key laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education Tsinghuo University Beijing 100084 China

Activation of molecular O2 is the most critical step in gold-catalyzed oxidation reactions; however, the underlying mechanisms of this process remain under debate. In this study, we propose an alternative O2 activation pathway with the assistance of hydrogen-containing substrates using density functional theory. It is demonstrated that the co-adsorbed H-containing substrates （R-H） not only enhance the adsorption of O2, but also transfer a hydrogen atom to the adjacent O2, leading to O2 activation by its transformation to a hydroperoxyl （OOH） radical species. The activation barriers of the H-transfer from 16 selected R-H compounds （H2O, CH3OH, NH2CHCOOH, CH3CH=CH2, （CH3）2SiH2, etc.） to the co-adsorbed O2 are lower than 0.50 eV in most cases, indicating the feasibility of the activation of O2 via OOH under mild conditions. The formed OOH oxidant, with an increased O-O bond length of -1.45 A, either participates directly in oxidation reactions through the end-on oxygen atom, or dissociates into atomic oxygen and hydroxyl （OH） by crossing a fairly low energy barrier of 0.24 eV. Using CO oxidation as a probe, we have found that OOH has superior activity than activated O2 and atomic oxygen. This study reveals a new pathway for the activation of O2, and may provide insight into the oxidation catalysis of nanosized gold.

关键词： O2 activation gold cluster adsorption dissociation hydroperoxyl

News Keyword Extraction Algorithm Based on Semantic Clustering and Word Graph Model

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tsinghua science and Technology 2021年第6期26卷 886-893页

作者： Ao Xiong Derong Liu Hongkang Tian Zhengyuan Liu Peng Yu Michel Kadoch State Key laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China Ecole de Technologie Superieure Universitedu QuebecMontrealH3C 1K3Canada

The internet is an abundant source of news every day. Thus, efficient algorithms to extract keywords from the text are important to obtain information quickly. However, the precision and recall of mature keyword extraction algorithms need improvement. TextRank, which is derived from the PageRank algorithm, uses word graphs to spread the weight of words. The keyword weight propagation in Text Rank focuses only on word frequency. To improve the performance of the algorithm, we propose Semantic Clustering TextRank(SCTR), a semantic clustering news keyword extraction algorithm based on TextRank. Firstly, the word vectors generated by the Bidirectional Encoder Representation from Transformers(BERT) model are used to perform k-means clustering to represent semantic clustering. Then, the clustering results are used to construct a TextRank weight transfer probability matrix. Finally,iterative calculation of word graphs and extraction of keywords are performed. The test target of this experiment is a Chinese news library. The results of the experiment conducted on this text set show that the SCTR algorithm has greater precision, recall, and F1 value than the traditional TextRank and Term Frequency-Inverse Document Frequency(TF-IDF) algorithms.

关键词： keyword extraction TextR ank semantics word vector

Learning Behavior-Aware Cognitive Diagnosis for Online Education Systems

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国际计算机前沿大会会议论文集 2021年第2期 385-398页

作者： Yiming Mao Bin Xu Jifan Yu Yifan Fang Jie Yuan Juanzi Li Lei Hou Global Innovation Exchange(GIX)Institute Tsinghua UniversityBeijing 100084China Department of Computer science and Technology BNRistTsinghua UniversityBeijing 100084China KIRC Institute for Artificial IntelligenceTsinghua UniversityBeijing 100084China

Cognitive diagnosis,which aims to diagnose students’knowledge proficiency,is crucial for numerous online education applications,such as personalized exercise *** methods in this area mainly exploit students’exercising records,which ignores students’full learning process in online education ***,the latent relation of exercises with course structure and texts is still *** this paper,a learning behavior-aware cognitive diagnosis(LCD)framework is proposed for students’cognitive modeling with both learning behavior records and exercising *** concept of LCD was first introduced to characterize students’knowledge proficiency more ***,a course graph was designed to explore rich information existed in course texts and ***,an interaction function was put forward to explore complex relationships between students,exercises and *** experiments on a real-world dataset prove that LCD predicts student performance more effectively,the output of LCD is also interpretable.

关键词： Cognitive diagnosis Intelligent education Graph neural network

The Effects of a Low-Temperature GaN Interlayer on the Performance of InGaN/GaN Solar Cells

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Chinese Physics Letters 2013年第2期30卷 247-249页

作者： LI Liang ZHAO De-Gang JIANG De-Sheng LIU Zong-Shun CHEN Ping WU Liang-Liang LE Ling-Cong WANG Hui YANG Hui State Key laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesP.O.Box 912Beijing 100083 Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of SciencesSuzhou 215123

An InGaN/GaN p-i-n solar cell inserted with a 5-nm low-temperature(LT)GaN interlayer between the p-GaN cap layer and the InGaN i-layer is grown on a c-plane sapphire substrate by metal organic chemical vapor *** effects of the LT GaN interlayer on the performance of the InGaN/GaN solar cells are *** is found that the LT-GaN interlayer prevents the extension of threading dislocations from the InGaN layer to the p-GaN layer and improves the crystal quality of both the p-GaN cap layer and the InGaN i-layer,ultimately leading to an increasing external quantum efficiency and photocurrent density of the InGaN/GaN solar cells.

关键词： InGaN/GaN GaN sapphire

Parity-time-symmetric whispering-gallery mode nanoparticle sensor[Invited]

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Photonics Research 2018年第5期6卷 I0004-I0011页

作者： WEIJIAN CHEN JING ZHANG BO PENG SAHIN KAYA OZDEMIR XUDONG FAN LAN YANG Department of Electrical and Systems Engineering Washington UniversitySt.LouisMissouri 63130USA Department of Automation Tsinghua UniversityBeijing 100084China Department of Biomedical Engineering University of MichiganAnn ArborMichigan 48109USA

We present a study of single nanoparticle detection using parity-time （PT） symmetric whispering-gaUery mode （WGM） resonators. Our theoretical model and numerical simulations show that, with balanced gain and loss, the PT-symmetric WGM nanoparticle sensor, tailored to operate at PT phase transition points （also called exceptional points）, exhibits significant enhancement in frequency splitting when compared with a single WGM nanopartide sensor subject to the same perturbation. The presence of gain in the PT-symmetric system leads to narrower linewidth, which helps to resolve smaller changes in frequency splitting and improve the detection limit of nanoparticle sensing. Furthermore, we also provide a general method for detecting multiple nanopartides entering the mode volume of a PT-symmetric WGM sensor one by one. Our study shows the feasibility of PT-symmetric WGM resonators for ultrasensitive single nanoparticle and biomolecule sensing.

关键词： arity-time-symmetric whispering-gallery mode nanoparticle sensor

Origin and Evolution of Core Components Responsible for Monitoring Light Environment Changes during Plant Terrestrialization

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Molecular Plant 2019年第6期12卷 847-862页

作者： Xue Han Xin Chang Zhenhua Zhang Haodong Chen Hang He Bojian Zhong Xing Wang Deng School of Advanced Agriculture sciences and School of Life sciences State Key Laboratory of Protein and Plant Gene Research Peking University Beijing 100871 China College of Life sciences Nanjing Normal University Nanjing 210046 China

Light serves as the source of energy as well as an information signal for photosynthetic plants. During evolution, plants have acquired the ability to monitor environmental light radiation and adjust their developmental patterns to optimally utilize light energy for photosynthesis. The mechanisms of light perception and signal transduction have been comprehensively studied in past decades, mostly in a few model plants, including Arabidopsis thaliana. However, systematic analyses of the origin and evolution of core components involved in light perception and signaling are still lacking. In this study, we took advantage of the recently sequenced genomes and transcriptomes covering all the main Archaeplastida clades in the public domain to identify orthologous genes of core components involved in light perception and signaling and to reconstruct their evolutionary history. Our analyses suggested that acclimation to different distribution of light quality in new environments led to the origination of specific light signaling pathways in plants. The UVR8 (UV Resistance Locus 8) signaling pathway originated during the movement of plants from the deeper sea to shallow water and enabled plants to deal with ultraviolet B light (UV-B). After acquisition of UV-B adaptation, origination of the phytochrome signaling pathway helped plants to colonize water surface where red light became the prominent light energy source. The seedling emergence pathway, which is mediated by a combination of light and phytohormone signals that orchestrate plant growth pattern transitions, originated before the emergence of seed plants. Although cryptochromes and some key components of E3 ubiquitin ligase systems already existed before the divergence of the plant and animal kingdoms, the coevolution and optimization of light perception and downstream signal transduction components, including key transcription factors and E3 ubiquitin ligase systems, are evident during plant terrestrialization.

关键词： evolution UVR8 signaling pathway phytochrome signaling pathway seedling emergence pathway COP1/SPA complex plant terrestrialization

Search for the doubly charmed baryon ■

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science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 8-22页

作者： R.Aaij C.Abellán Beteta T.Ackernley B.Adeva M.Adinolfi H.Afsharnia C.A.Aidala S.Aiola Z.Ajaltouni S.Akar P.Albicocco J.Albrecht F.Alessio M.Alexander A.Alfonso Albero G.Alkhazov P.Alvarez Cartelle A.A.Alves Jr S.Amato Y.Amhis L.An L.Anderlini G.Andreassi M.Andreotti F.Archilli J.Arnau Romeu A.Artamonov M.Artuso K.Arzymatov E.Aslanides M.Atzeni B.Audurier S.Bachmann J.J.Back S.Baker V.Balagura W.Baldini A.Baranov R.J.Barlow S.Barsuk W.Barter M.Bartolini F.Baryshnikov G.Bassi V.Batozskaya B.Batsukh A.Battig V.Battista A.Bay M.Becker F.Bedeschi I.Bediaga A.Beiter L.J.Bel V.Belavin S.Belin N.Beliy V.Bellee K.Belous I.Belyaev G.Bencivenni E.Ben-Haim S.Benson S.Beranek A.Berezhnoy *** D.Berninghoff H.C.Bernstein E.Bertholet A.Bertolin C.Betancourt F.Betti M.O.Bettler Ia.Bezshyiko S.Bhasin J.Bhom M.S.Bieker S.Bifani P.Billoir A.Birnkraut A.Bizzeti M.Bjφrn M.P.Blago T.Blake F.Blanc S.Blusk D.Bobulska V.Bocci O.Boente Garcia T.Boettcher A.Boldyrev A.Bondar N.Bondar S.Borghi M.Borisyak M.Borsato J.T.Borsuk T.J.V.Bowcock C.Bozzi S.Braun A.Brea Rodriguez M.Brodski J.Brodzicka A.Brossa Gonzalo D.Brundu E.Buchanan A.Buonaura C.Burr A.Bursche J.S.Butter J.Buytaert W.Byczynski S.Cadeddu H.Cai R.Calabrese S.Cali R.Calladine M.Calvi M.Calvo Gomez A.Camboni P.Campana D.H.Campora Perez L.Capriotti A.Carbone G.Carboni R.Cardinale A.Cardini P.Carniti K.Carvalho Akiba A.Casais Vidal G.Casse M.Cattaneo G.Cavallero R.Cenci J.Cerasoli M.G.Chapman M.Charles Ph.Charpentier G.Chatzikonstantinidis M.Chefdeville V.Chekalina C.Chen S.Chen A.Chernov S.-G.Chitic V.Chobanova M.Chrzaszcz A.Chubykin P.Ciambrone M.F.Cicala X.Cid Vidal G.Ciezarek F.Cindolo P.E.L.Clarke M.Clemencic H.V.Cliff J.Closier J.L.Cobbledick V.Coco J.A.B.Coelho J.Cogan E.Cogneras L.Cojocariu P.Collins T.Colombo A.Comerma-Montells A.Contu N.Cooke G.Coombs S.Coquereau G.Corti C.M.Costa Sobral B.Couturier D.C.Craik J.Crkovska A.Crocombe M.Cruz Torres R.Currie C.L.Da Silva E.Dall'Occo J.Dalseno C.D'Ambrosio A.Danilina P.d'Argent A.Davis O.De Aguiar Francisco K.De Bruyn S.De Capua M Centro Brasileiro de Pesquisas Fisicas(CBPF) Rio de JaneiroBrazil Universidade Federal do Rio de Janeiro(UFRJ) Rio de JaneiroBrazil Center for High Energy Physics Tsinghua UniversityBeijingChina School of Physics State Key laboratory of Nuclear Physics and Technology Peking UniversityBeijingChina University of Chinese Academy of sciences BeijingChina Institute Of High Energy Physics(IHEP) BeijingChina Institute of Particle Physics Central China Normal UniversityWuhanHubeiChina Univ.Grenoble Alpes Univ.Savoie Mont BlancCNRSIN2P3-LAPPAnnecyFrance Universite Clermont Auvergne CNRS/IN2P3LPCClermont-FerrandFrance Aix Marseille Univ CNRS/IN2P3CPPMMarseilleFrance LAL Univ.Paris-SudCNRS/IN2P3Universite Paris-SaclayOrsayFrance LPNHE Sorbonne Universite Paris Diderot Sorbonne Paris Cite CNRS/IN2P3ParisFrance I.Physikalisches Institut RWTH Aachen UniversityAachenGermany Fakultat Physik Technische Universitat DortmundDortmundGermany Max-Planck-Institut für Kernphysik(MPIK) HeidelbergGermany Physikalisches Institut Ruprecht-Karls-Universitat HeidelbergHeidelbergGermany School of Physics University College DublinDublinIreland INFN Sezione di Bari BariItaly INFN Sezione di Bologna BolognaItaly INFN Sezione di Ferrara FerraraItaly INFN Sezione di Firenze FirenzeItaly INFN Laboratori Nazionali di Frascati FrascatiItaly INFN Sezione di Genova GenovaItaly INFN Sezione di Milano-Bicocca MilanoItaly INFN Sezione di Milano MilanoItaly INFN Sezione di Cagliari MonserratoItaly INFN Sezione di Padova PadovaItaly INFN Sezione di Pisa PisaItaly INFN Sezione di Roma Tor Vergata RomaItaly INFN Sezione di Roma La Sapienza RomaItaly Nikhef national Institute for Subatomic Physics AmsterdamNetherlands Nikhef national Institute for Subatomic Physics and VU University Amsterdam AmsterdamNetherlands Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of sciences KrakowPoland AGH-University of science and Technology Faculty of Physics and Applied Computer ScienceKrakowPoland Natio

A search for the doubly charmed baryon ■^+cc is performed through its decay to theΛ^+c K^-π^+ final state,using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7,8 and 13 *** data correspond to a total integrated luminosity of 9 fb^-*** significant signal is observed in the mass range from 3.4 to 3.8 GeV/c^*** limits are set at 95%credibility level on the ratio of the ■^+cc production cross-section times the branching fraction to that ofΛ^+c and ■^++cc *** limits are determined as functions of the ■^+cc mass for different lifetime hypotheses,in the rapidity range from 2.0 to 4.5 and the transverse momentum range from 4 to 15 GeV/c.

关键词： charmed baryons limits on production of particles charmed quarks experimental tests

Spatio-temporal analysis and simulation on shallow rainfall-induced landslides in China using landslide susceptibility dynamics and rainfall I-D thresholds

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science China Earth sciences 2017年第4期60卷 720-732页

作者： LI WeiYue LIU Chun Marco SCAIONI SUN WeiWei CHEN Yu YAO DongJing CHEN Sheng HONG Yang ZHANG KaiHang CHENG GuoDong Institute of Urban Study Shanghai Normal University Shanghai 200234 China Cold and Arid Region Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China College of Surveying and Geo-Informatics Tongji University Shanghai 200234 China Department of Architecture Built Environment and Construction Engineering Politecnico Milano Milano 20133 Italy College of Architectural Engineering Civil Engineering and Environment Ningbo University Ningbo 315211 China Shandong Academy of Building Research Jinan 250031 China Department of Geography Shanghai Normal University Shanghai 200234 China School of Atmospheric sciences Sun Yat-sen University Guangzhou 510275 China Key laboratory of Beibu Gulf Environmental Evolution and Resources Utilization Guangxi Teachers Education University Nanning 530001 China School of Civil Engineering and Environmental sciences University of Oklahoma OK 73074 USA Department of Hydraulic Engineering Tsinghua University Beijing 100084 China Institute of Tourism Shanghai Normal University Shanghai 200234 China

An empirical simulation method to simulate the possible position of shallow rainfall-induced landslides in China has been *** study shows that such a simulation may be operated in real-time to highlight those areas that are highly prone to rainfall-induced landslides on the basis of the landslide susceptibility index and the rainfall intensity-duration(I-D) ***,the study on landslide susceptibility in China is *** entire territory has been classified into five categories,among which high-susceptibility regions(Zone 4-'High' and 5-'Very high') account for 4.15%of the total extension of ***,rainfall is considered as an external triggering factor that may induce landslide ***-time satellite-based TMPA3B42 products may provide real rainfall spatial and temporal patterns,which may be used to derive rainfall duration time and *** using a historical record of 60 significant past landslides,the rainfall I-D equation has been *** rainfall duration time that may trigger a landslide has resulted between 3 hours and 45 *** combination of these two aspects can be exploited to simulate the spatiotemporal distribution of rainfall-induced landslide hazards when rainfall events exceed the rainfall I-D thresholds,where the susceptibility category is 'high' or 'very high'.This study shows a useful tool to be part of a systematic landslide simulation methodology,potentially providing useful information for a theoretical basis and practical guide for landslide prediction and mitigation throughout China.

关键词： Surface and subsurface runoff Runoff-produced physical and chemical deposits Precipitated salts and water circulation Groundwater supply mechanism Badain Jaran Desert