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Experimental demonstration of a quantum downstream access network in continuous variable quantum key distribution with a local local oscillator

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Photonics Research 2024年第6期12卷 1262-1273页

作者： DENGKE QI XIANGYU WANG zhenghua li JIAYU MA ZIYANG CHEN YUEMING LU SONG YU State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Trustworthy Distributed Computing and Service(MoE) Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronicsand Center for Quantum Information TechnologyPeking UniversityBeijing 100871China

Quantum networks provide opportunities and challenges across a range of intellectual and technical frontiers,including quantum computation,communication,and *** traditional communication networks,quantum networks utilize quantum bits rather than classical bits to store and transmit *** key distribution(QKD)relying on the principles of quantum mechanics is a key component in quantum networks and enables two parties to produce a shared random secret key,thereby ensuring the security of data *** this work,we propose a cost-effective quantum downstream access network structure in which each user can get their corresponding key information through terminal *** on this structure,we demonstrate the first four-end-users quantum downstream access network in continuous variable QKD with a local local *** contrast to point-to-point continuous variable QKD,the network architecture reevaluates the security of each user and accounts for it accordingly,and each user has a lower tolerance for excess noise as the overall network expands with more ***,the feasibility of the experiment is based on the analysis of the theoretical model,noise analysis,and multiple techniques such as the particle filter and adaptive equalization algorithm used to suppress excess *** results show that each user can get a low level of excess noise and can achieve secret key rates of 546 kbps,535 kbps,522.5 kbps,and 512.5 kbps under a transmission distance of 10 km,respectively,with the finite-size block of 1×10~*** not only verifies the good performance but also provides the foundation for the future multi-user quantum downstream access networks.

关键词： quantum oscillator local

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基于无监督模型的低资源词性标注实验对比和分析

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厦门大学学报（自然科学版） 2024年第2期63卷 221-231页

作者：李扬周厚全李正华张民苏州大学计算机科学与技术学院江苏苏州215006

[目的]研究无监督词性标注模型在低资源语言上的性能表现.[方法]尝试利用无监督词性标注模型,包括高斯隐马尔科夫模型(Gaussian HMM,GHMM)、最大化互信息模型(mutual information maximization, MIM)与条件随机场自编码器(conditional r... 详细信息

[目的]研究无监督词性标注模型在低资源语言上的性能表现.[方法]尝试利用无监督词性标注模型,包括高斯隐马尔科夫模型(Gaussian HMM,GHMM)、最大化互信息模型(mutual information maximization, MIM)与条件随机场自编码器(conditional random filed autoencoder, CRF-AE),展开低资源词性标注实验.基于对前人工作的凝练,在英文宾州树库上设置了少样本和词典标注两种低资源场景.[结果]无监督词性标注模型能够在少样本场景中超越条件随机场模型,但在词典标注场景中却始终逊色于条件随机场模型.[结论]无监督损失更加擅长对高频词进行建模,使得模型在少样本场景下获得更好的性能表现;同时无监督损失倾向于生成更加均匀的词性分布,从而降低模型在词典标注场景下的性能.

关键词：词性标注低资源学习词典标注无监督学习

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农村中学生“非贫辍学”行为的形成机理——以Y省C自治州为例

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少年儿童研究 2024年第2期 35-41页

作者：李正华杨诚李昕暨南大学公共管理学院/应急管理学院华南师范大学哲学与社会发展学院云南楚雄实验中学

基于空间生产理论,采用深度访谈法,探讨农村中学生发生辍学行为的形成机理。研究发现,农村中学生发生辍学行为是物理空间、符号空间、人际空间、体验空间相互作用的结果。在不同的空间体验中,辍学生经历了从差生个体到差生群体的价值认... 详细信息

基于空间生产理论,采用深度访谈法,探讨农村中学生发生辍学行为的形成机理。研究发现,农村中学生发生辍学行为是物理空间、符号空间、人际空间、体验空间相互作用的结果。在不同的空间体验中,辍学生经历了从差生个体到差生群体的价值认同,最终这种价值认同与学校的规训认同发生冲突而导致辍学行为发生。

关键词：农村中学生非贫辍学空间生产理论

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基于实例的词性标注数据错误检测

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山西大学学报(自然科学版) 2024年第2期47卷 251-259页

作者：崔秀莲严福康李正华苏州大学计算机科学与技术学院

由于深度学习框架在可解释性上的缺乏，本文将基于实例的方法首次应用到词性标注数据错误检测任务，旨在充分利用模型学到的实例之间的相似度信息。首先，本文基于预训练语言模型，实现了基于实例的词性标注模型，在CTB7数据集上的预测... 详细信息

由于深度学习框架在可解释性上的缺乏，本文将基于实例的方法首次应用到词性标注数据错误检测任务，旨在充分利用模型学到的实例之间的相似度信息。首先，本文基于预训练语言模型，实现了基于实例的词性标注模型，在CTB7数据集上的预测准确率和基于标准分类器的模型相当，达96.76%。进而，本文提出了一种基于实例的标注错误检测方法。为了获得真实检错数据集，本文采用不同方法对CTB7测试集进行自动错误检测，并人工标注候选错误，最终获得2 016个真实标注错误，约占所有8万多词中的2.5%。检错数据集上的实验表明，基于实例的方法的检错准确率达41.48%。

关键词：词性分类标注错误数据集语义相似度 CTB7数据集

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科普助力中国式现代化的历程、路径与经验

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科普研究 2024年第3期19卷 5-11+99页

作者：李正华王慧斌王挺谢小军中国社会科学院当代中国研究所中国科普研究所

历经革命、建设、改革、强国时期，中国共产党领导的中国式现代化一贯强调科学技术的关键作用，注重发挥科学普及的战略功能。科普通过助力解决人口规模巨大带来的难题和挑战，助力全体人民共同富裕和共享发展成果，助力物质文明和精神... 详细信息

历经革命、建设、改革、强国时期，中国共产党领导的中国式现代化一贯强调科学技术的关键作用，注重发挥科学普及的战略功能。科普通过助力解决人口规模巨大带来的难题和挑战，助力全体人民共同富裕和共享发展成果，助力物质文明和精神文明相协调，助力人与自然和谐共生，助力走和平发展道路等路径，对中国式现代化进程起到了强基赋能作用，并形成了坚持中国共产党的领导、坚持“把科学交给人民”、坚持服务大局工作、坚持提升科普能力、坚持文明交流互鉴的历史经验。

关键词：科普中国式现代化中国共产党

来源：博看期刊

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Hierarchical LSTM with char-subword-word tree-structure representation for Chinese named entity recognition

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Science China(Information Sciences) 2020年第10期63卷 74-88页

作者： Chen GONG zhenghua li Qingrong XIA Wenliang CHEN Min ZHANG School of Computer Science and Technology Soochow University

Chinese named entity recognition(CNER) aims to identify entity names such as person names and organization names from Chinese raw text and thus can quickly extract the entity information that people are concerned about from large-scale texts. Recent studies attempt to improve performance by integrating lexicon words into char-based CNER models. These existing studies, however, usually focus on leveraging the context-free words in lexicon without considering the contextual information of words and subwords in the sentences. To address this issue, in addition to utilizing the lexicon words, we further propose to construct a hierarchical tree structure representation composed of characters, subwords and context-aware predicted words from segmentor to represent each sentence for CNER. Based on the tree-structure representation, we propose a hierarchical long short-term memory(HiLSTM) framework, which consists of hierarchical encoding layer, fusion layer and CRF layer, to capture linguistic knowledge at different levels. On the one hand, the interactions within each level help to obtain the contextual information. On the other hand, the propagations from the lower-levels to the upper-levels can provide additional semantic knowledge for CNER. Experimental results on three widely used CNER datasets show that our proposed HiLSTM model achieves significant improvement over several strong benchmark methods.

关键词： natural language processing named entity recognition representation learning neural networks

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Enhanced photocatalytic activity of (La, N) co-doped TiO_2 by TiCl_4 sol-gel autoigniting synthesis

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Journal of University of Science and Technology Beijing 2007年第6期14卷 552-557页

作者： Zhongqing liu Yanping Zhou zhenghua li Yichao Wang Changchun Ge Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

（La, N） co-doped TiO2 photocatalysts were synthesized using TiC14 sol-gel autoignidng synthesis （SAS） starting from a complex compound system of TiCl4-La（NO3）3-citric acid-NH4NO3-NHyH2O, in which the （La, N） co-doped process was accompushed in the formation of TiO2 nanocrystals. The prepared samples were characterized by using X-ray diffraction （XRD）, X-ray photoemission spectroscopy （XPS） and UV-vis diffuse reflectance spectra. The results indicated that nitrogen and lanthanum were incorporated into the lattice and interstices of titania nanocrystals, which resulted in narrowing the band gap and promoting the separation of photoexcited hole-electron pairs, respectively, and showing expected red-shifts and enhanced photocatalytic activity under visible light. The mechanism on nitrogen doping and enhancement in photocatalyfic activity of （La, N） co-doped titania by SAS was discussed in detail.

关键词： photocatalyst co-doping titanium dioxide sol-gel autoigniting synthesis photocatalytic activity

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Development of cryptotanshinone-loaded pellets for angina chronotherapy:In vitro/in vivo prediction and evaluation

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Asian Journal of Pharmaceutical Sciences 2018年第4期13卷 310-316页

作者： zhenghua li Shuangshuang Zhang Hongxiang Yan Jianping liu Department of Pharmaceutics China Pharmaceutical University

The clinical manifestations of variant angina is unevenly distributed during the 24 h, thusthe in vivo performance of drugs should be tailored according to the angina circadianrhythm. Cryptotanshinone(CTN) is one of the representative bioactive lipid-soluble com-ponents of Danshen which has been commonly used for cardiovascular diseases such asangina pectoris. The aim of this study was to develop a novel CTN sustained-released pel-lets(CTN-SRPs) to precisely synchronize the CTN plasma concentrations with predictedoccurrence of angina pectoris for angina chronotherapy. A deconvolution-based methodwas applied to develop and optimize the CTN-SRPs. The plasma concentration-time curveof CTN immediate-released formulation after oral administration in rats was used as theweight function. The predicted plasma concentration-time curve of CTN-SRPs simulatedaccording to the incidence of variant angina during 24 h was used as the response func-tion. Then the desired drug release profile of CTN-SRPs was calculated based on deconvo-lution using weight function and response function, and subsequently used for guiding theformulation optimization. CTN-SRPs were prepared with the combinations of PVP, polox-amer 127 and EC as matrix using fluidized bed technology. An orthogonal design was em-ployed to obtain the optimal formulation with its release profile similar with the desiredone. Pharmacokinetic studies validated that the actual plasma concentration-time curve ofthese optimized CTN-SRPs was similar with the predicted one. In addition, the percent er-rors(%PE) of CTN plasma concentrations in 8–12 h were less than 10%. In conclusion, thisdeconvolution-based method could be applied to adjust the in vivo performance of drugs forangina chronotherapy.

关键词： Chronotherapy Deconvolution Angina pectoris Cryptotanshinone In vitro/in vivo performance Control release

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Micromagnetic studies of perpendicular recording FePt media with controllable grain size distributions

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Rare Metals 2006年第z1期25卷 436-439页

作者： DONG Zhong PIAO Kun SHE Shengxian WEI Dan li zhenghua WEI Fulin Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Research Institute of Magnetic Materials Lanzhou UniversityLanzhou 730000China

A 3-dimensional(3D)micromagnetic model combined with Fast Fourier Transform(FFT)method was built up to study the writability in the L1_(0)FePt perpendicular *** effects of controllable grain size distributions were studied by grain growth *** is found that the cross-track-averaged magnetization changes little between the L1_(0)FePt medium with uniform or non-uniform grain size distribution.

关键词： perpendicular recording L1_(0)FePt medium controllable grain size distributions micromagnetic simulation

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Improving the wind and wave estimation of dual-frequency altimeter JASON1 in Typhoon Shanshan and considering the rain effects

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Acta Oceanologica Sinica 2008年第5期27卷 49-62页

作者： YANG Le liN Mingsen ZOU Juhong li zhenghua PAN Delu Science Department Nanjing University of Science and Technology Nanjing 210094 China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China National Satellite Ocean Application Service State Oeeanic Administration Beijing 10008 China

Altimetry data have been widely used in various fiehts of oceanography, including the extreme weather events such as tropical cyclones, typhoons, and hurricanes. The performance of JASON1 in Typhoon Shanshan is assessed by examining the sensor geophysical data record and illustrates how the measured return waveform, significant wave height, and backscatter are all affected by various factors associated with the typhoon, with details by the rain are illustrated. The correction method to maintain accurate wave height and wind speed measurements in Typhoon Shanshan and the results are presented. Furthermore, the additional results of rain rate and typhoon eye diameter can be retrieved. Because of the lack of in-situ measurements of wind, wave, and rain rate at Typhoon Shanshan, results are compared with the forecasted typhoon data and a good agreement is found.

关键词： altimeter waveform typhoon rain high wind speed

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