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Research in Astronomy and Astrophysics 2024年第8期24卷 32-41页

作者： Yingze Shan Xiaoxuan Liu Xing Yang haoyu yuan Houjun Lü Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Department of Astronomy School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China

Theoretically,a supra-massive neutron star or magnetar may be formed after the merger of binary neutron ***210323A is a short-duration gamma-ray burst(GRB)with a duration of lasting~1 *** light curve of the prompt emission of GRB 210323A shows a signal-peaked structure and a cutoff power-law model can adequately fit the spectra with E_p=1826±*** interestingly,it has an extremely long-lasting plateau emission in the X-ray afterglow with a duration of~10^(4)s,and then follows a rapid decay with a decay slope~*** temporal feature is challenging by invoking the external shock *** this paper,we suggest that the observed long-lasting X-ray plateau emission is caused by the energy injection of dipole radiation from supra-massive magnetar,and the abrupt decay following the longlasting X-ray plateau emission is explained by supra-massive magnetar collapsing into a black *** is the short GRB(SGRB)with the longest X-ray internal plateau emission powered by a supra-massive neutron *** this is the case,one can estimate the physical parameters of a supra-massive magnetar,and compare with other *** also discuss the possible gravitational-wave emission,which is powered by a supra-massive magnetar and its detectability,and the possible kilonova emission,which is powered by r-process and magnetar spin-down to compare with the observed data.

关键词： (stars)gamma-ray burst general-(stars)gamma-ray burst individual(GRB 210323A)-stars magnetars

Naphthalene diimide-based cathode interlayer material enables 20.2% efficiency in organic photovoltaic cells

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Science China Chemistry 2024年

作者： Yue Yu Jianqiu Wang Zhihao Chen Yang Xiao Zhen Fu Tao Zhang haoyu yuan Xiao-Tao Hao Long Ye Yong Cui Jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences School of Physics State Key Laboratory of Crystal Materials Shandong University Beijing Advanced Innovation Center for Soft Matter Science and Engineering College of Materials Science and Engineering Beijing University of Chemical Technology School of Materials Science and Engineering Tianjin University

Cathode interlayer(CIL) materials play an important role in improving the power conversion efficiency(PCE) of organic photovoltaic(OPV) cells. However, the current understanding of the structure-property relationship in CIL materials is limited, and systematic studies in this regard are scarce. Here, two new CIL materials, NDI-PhC 4 and NDI-PhC 6 were synthesized by varying the alkylamine chain length on the NDI-Ph core. Our investigation reveals a systematic variation in the physical and chemical properties of these materials with increasing alkylamine chain length. Specifically, we observe a sequential decrease in melting point and self-doping effect, accompanied by an enhancement in crystallinity. Among these CIL materials, NDI-PhC 4 has a notable balance across various performance metrics. It also exhibits excellent surface modification capabilities, leading to a low surface roughness. Consequently, OPV cells based on NDI-PhC 4 achieve a PCE of 20.2%, which is one of the highest reported efficiencies for OPV cells. In addition, the appropriate melting point of NDI-PhC 4 contributes to the excellent stability of OPV cells.

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融合自监督的协同注意图学习会话推荐

小型微型计算机系统 2024年第8期45卷 1878-1886页

作者：王永贵袁浩钰辽宁工程技术大学电子与信息工程学院辽宁葫芦岛125105

基于图神经网络的会话推荐目的是利用给定的匿名交互序列预测用户下次将交互的潜在项目.为解决图神经网络方法中存在的过度平滑问题和现有的会话推荐忽略了数据稀疏性影响,以及因使用交叉熵而产生严重的过拟合问题.本文提出了一种融合... 详细信息

基于图神经网络的会话推荐目的是利用给定的匿名交互序列预测用户下次将交互的潜在项目.为解决图神经网络方法中存在的过度平滑问题和现有的会话推荐忽略了数据稀疏性影响,以及因使用交叉熵而产生严重的过拟合问题.本文提出了一种融合自监督的协同注意图学习会话推荐模型(SI-CAGL).首先SI-CAGL在学习到会话中项目的准确表示,其次使用协同注意图学习与修改自注意力机制的方法进行自监督学习,最后使用修正边缘平滑函数与归一化相结合的方法进行预测.在两个真实数据集上进行多次实验,与先进基线模型相比,SI-CAGL在Diginetica上Recall@20和MRR@20至少提升了3.28%和3.38%,在Gowalla上Recall@20和MRR@20至少提升了2.88%和2.13%,推荐性能有明显提升.

关键词：自监督学习协同注意图学习会话推荐修正边缘平滑函数

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一款用于双向传输高速接口的阻抗校准电路

微电子学与计算机 2024年第3期41卷 105-111页

作者：许皓王佳维袁昊煜王自强清华大学集成电路学院北京100084 北京奕斯伟计算技术股份有限公司北京100176

在具有双向传输功能的高速串行接口中,发射机输出端的两个电阻对电路性能有很大的影响。为提升电路在复杂环境中的工作性能,需要对电阻进行阻抗校准。传统的阻抗校准存在着功耗高、面积大、系统误差大、收敛时间长等缺点。针对上述问题... 详细信息

在具有双向传输功能的高速串行接口中,发射机输出端的两个电阻对电路性能有很大的影响。为提升电路在复杂环境中的工作性能,需要对电阻进行阻抗校准。传统的阻抗校准存在着功耗高、面积大、系统误差大、收敛时间长等缺点。针对上述问题,设计了一款用于双向传输高速串行接口的阻抗校准电路,通过共用电流源的方式有效地减小了阻抗校准电路的面积及功耗,并消除了电流源失配带来的系统误差;引入了带有失调消除的比较器,并对比较器中存在的开关管漏电及时钟馈通等效应进行优化,降低了校准电路的系统误差;使用了逐次逼近寄存器(Successive Approximation Register,SAR)逻辑对最佳的电阻校准控制码进行查找,从而减小了收敛时间。在SMIC 40 nm工艺上实现了一款高精度,低功耗,且可对两个电阻分别进行调节的阻抗校准电路。对两个待校准电阻进行蒙特卡洛分析,阻抗校准的3σ值分别为201.76 mΩ,198.80 mΩ,阻抗校准电路整体功耗为4.205 mW。

关键词：高速串行接口阻抗校准双向传输失调消除

Estimating inter-area dominant oscillation mode in bulk power grid using multi-channel continuous wavelet transform

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Journal of Modern Power Systems and Clean Energy 2016年第3期4卷 394-405页

作者： Tao JIANG Linquan BAI Guoqing LI Hongjie JIA Qinran HU haoyu yuan Department of Electrical Engineering Northeast Dianli UniversityJilin 132012China Department of Electrical Engineering and Computer Science University of TennesseeKnoxvilleTN 37996USA Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138USA

This paper proposes a novel continuous wavelet transform(CWT) based approach to holistically estimate the dominant oscillation using measurement data from multiple channels. CWT has been demonstrated to be effective in estimating power system oscillation *** singular value decomposition(SVD) technique, the original huge phasor measurement unit(PMU) datasets are compressed to finite useful measurement data which contain critical dominant oscillation information. Further,CWT is performed on the constructed measurement signals to form wavelet coefficient matrix(WCM) at the same dilation. Then, SVD is employed to decompose the WCMs to obtain the maximum singular value and its right eigenvector. A singular value vector with the entire dilation is constructed through the maximum singular values. The right eigenvector corresponding to the maximum singular value in the singular-value vector is adopted as the input of CWT to estimate the dominant modes. Finally, the proposed approach is evaluated using the simulation data from China Southern Power Grid(CSG) as well as the actual field-measurement data retrieved from the PMUs of *** simulation results demonstrate that the proposed approach performs well to holistically estimate the dominant oscillation modes in bulk power systems.

关键词： Continuous wavelet transform(CWT) Oscillation mode Phasor measurement unit(PMU) Singular value decomposition(SVD)

不同金属基MOFs应用于CO_(2)环加成反应

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广东化工 2024年第1期51卷 70-72,23页

作者：陈文静雷钱茜朱霖琳林杉鲍佳雯苑浩宇梁若雯宁德师范学院化学与材料学院福建宁德352100

在相对温和的反应条件下,利用简单的反应过程将CO_(2)固定,形成高附加价值的产物,是当前很受关注的一项科学技术挑战,其中环氧丙烷和CO_(2)的环加成反应是实现碳中性,固定CO_(2)的一条理想途径,CO_(2)的有效活化则是这个反应的前提。但... 详细信息

在相对温和的反应条件下,利用简单的反应过程将CO_(2)固定,形成高附加价值的产物,是当前很受关注的一项科学技术挑战,其中环氧丙烷和CO_(2)的环加成反应是实现碳中性,固定CO_(2)的一条理想途径,CO_(2)的有效活化则是这个反应的前提。但目前关于实验的反应过程和机理仍然是有待解决的问题。因此,在本研究中,我们通过合成不同金属基底的MOFs材料,分别进行CO_(2)与环氧丙烷的加成反应,分析最有利于反应进行的催化材料。实验结果表明,UiO-66-NH2的催化效果最好。本研究为不同材料的CO_(2)环加成反应的设计和应用提供一些新思路。

关键词： CO_(2) 环加成 UiO-66-NH_(2) MIL-125(Ti)-NH_(2) HKUST-1(Cu)

Channel estimation-based time-frequency neural network for post-equalization in underwater visible light communication

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Chinese Optics Letters 2024年第6期22卷 116-122页

作者： haoyu Zhang Li Yao Chaoxu Chen yuan Wei Chao Shen Jianyang Shi Junwen Zhang Ziwei Li Nan Chi Key Laboratory for Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringSchool of Information Science and TechnologyFudan UniversityShanghai 200433China Shanghai CIC of LEO Satellite Communication Technology Fudan UniversityShanghai 200433China Shanghai ERC of LEO Satellite Communication and Application Fudan UniversityShanghai 200433China

This Letter proposes a post-equalizer for underwater visible light communication(UVLC) systems that combines channel estimation and joint time-frequency analysis, named channel-estimation-based bandpass variable-order time-frequency network(CBV-TFNet). By utilizing a bandpass variable-order loss function with communication prior knowledge, CBVTFNet enhances communication performance and training stability. It enables lightweight implementation and faster convergence through a channel estimation-based mask. The superior performance of the proposed equalization method over Volterra and deep neural network(DNN)-based methods has been studied experimentally. Using bit-power loading discrete multitone (DMT) modulation, the proposed method achieves a transmission bitrate of 4.956 Gbps through a 1.2 m underwater channel utilizing only 38.15% of real multiplication calculations compared to the DNN equalizer and achieving a bitrate gain of440 Mbps and a significantly larger dynamic range over the LMS-Volterra equalizer. Results highlight CBV-TFNet's potential for future post-equalization in UVLC systems.

关键词： underwater visible light communication channel estimation post-equalizer neural network

Adding power of artificial intelligence to situational awareness of large interconnections dominated by inverter‐based resources

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High Voltage 2021年第6期6卷 924-937页

作者： Lin Zhu Yinfeng Zhao Yi Cui Shutang You Wenpeng Yu Shengyuan Liu He Yin Chang Chen Yuru Wu Wei Qiu Mirka Mandich Hongyu Li Adedasola Ademola Chengwen Zhang Chujie Zeng Xinlan Jia Weikang Wang haoyu yuan Huaiguang Jiang Jin Tan Yilu Liu The University of Tennessee KnoxvilleTennesseeUSA National Renewable Energy Laboratory GoldenColoradoUSA Oak Ridge National Laboratory Oak RidgeTennesseeUSA

Large‐scale power systems exhibit more complex dynamics due to the increasing inte-gration of inverter‐based resources(IBRs).Therefore,there is an urgent need to enhance the situational awareness capability for better monitoring and control of power grids dominated by *** a pioneering Wide‐Area Measurement System,FNET/GridEye has developed and implemented various advanced applications based on the collected synchrophasor measurements to enhance the situational awareness capability of large‐scale power *** study provides an overview of the latest progress of FNET/*** sensors,communication,and data servers are upgraded to handle ultra‐high density synchrophasor and point‐on‐wave data to monitor system dynamics with more *** importantly,several artificial intelligence(AI)‐based advanced appli-cations are introduced,including AI‐based inertia estimation,AI‐based disturbance size and location estimation,AI‐based system stability assessment,and AI‐based data authentication.

关键词： artificial handle inverter