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自然语言处理研究综述

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 89-111,F0002页

作者：赵铁军许木璠陈安东哈尔滨工业大学计算学部黑龙江哈尔滨150001

近年来,自然语言处理因在分析与建模人类语言任务领域取得诸多成果而备受关注。当前,大规模预训练语言模型展现出强大的对话问答和文本生成能力,带来自然语言处理研究的新一轮热潮。自然语言处理在机器翻译、文本摘要、信息抽取等领域... 详细信息

近年来,自然语言处理因在分析与建模人类语言任务领域取得诸多成果而备受关注。当前,大规模预训练语言模型展现出强大的对话问答和文本生成能力,带来自然语言处理研究的新一轮热潮。自然语言处理在机器翻译、文本摘要、信息抽取等领域应用广泛。文本首先讨论自然语言处理针对语言学四个不同层次文本信息的分析手段,对自然语言处理的基本任务组成进行概述;其次,讨论自然语言处理在具体下游任务中的应用现状,包括自然语言处理在具体任务中的应用历史、当前的研究趋势以及面临的挑战;最后,在大规模预训练语言模型研究对数据集提出更高要求的背景下,对自然语言处理领域已有的数据集及评测基准集等进行讨论。

关键词：自然语言处理句法分析语义分析机器翻译问答系统信息抽取

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COMPLEX SYSTEM ANALYSIS OF MARKET RETURN PERCOLATION MODEL ON SIERPINSKI CARPET LATTICE FRACTAL

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Journal of Systems Science & Complexity 2014年第4期27卷 743-759页

作者： dong Yanfang WANG jun Department of Mathematics College of ScienceBeijing Jiaotong University

This paper investigates the statistical behaviors of fluctuations of price changes in a stock *** Sierpinski carpet lattice fractal and the percolation system are applied to develop a new random stock price for the financial *** Sierpinski carpet is an infinitely ramified fractal and the percolation theory is usually used to describe the behavior of connected clusters in a random *** authors investigate and analyze the statistical behaviors of returns of the price model by some analysis methods,including multifractal analysis,autocorrelation analysis,scaled return interval ***,the authors consider the daily returns of Shanghai Stock Exchange Composite Index,and the comparisons of return behaviors between the actual data and the simulation data are exhibited.

关键词： Percolation return Sierpinski carpet lattice fractal statistical analysis stock market.

Highly Concentrated,Conductive,Defect-free Graphene Ink for Screen-Printed Sensor Application

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Nano-Micro Letters 2021年第6期13卷 17-30页

作者： dong Seok Kim Jae-Min jeong Hong jun Park Yeong Kyun Kim Kyoung G.Lee Bong Gill Choi Department of Chemical Engineering Kangwon National UniversitySamcheokGangwon-do 25913Republic of Korea Resources Utilization Research Center Korea Institute of Geoscience and Mineral ResourcesDaejeon 34132Republic of Korea Center for Nano Bio Development National Nanofab CenterDaejeon 34141Republic of Korea

Conductive inks based on graphene materials have received significant attention for the fabrication of a wide range of printed and flexible ***,the application of graphene fillers is limited by their restricted mass production and the low concentration of their *** this study,a highly concentrated and conductive ink based on defect-free graphene was developed by a scalable fluid dynamics process.A high shear exfoliation and mixing process enabled the production of graphene at a high concentration of 47.5 mg mL^(−1)for graphene *** screen-printed graphene conductor exhibits a high electrical conductivity of 1.49×10^(4)S m^(−1)and maintains high conductivity under mechanical bending,compressing,and fatigue *** on the as-prepared graphene ink,a printed electrochemical sodium ion(Na^(+))sensor that shows high potentiometric sensing performance was ***,by integrating a wireless electronic module,a prototype Na^(+)-sensing watch is demonstrated for the real-time monitoring of the sodium ion concentration in human sweat during the indoor exercise of a *** scalable and efficient procedure for the preparation of graphene ink presented in this work is very promising for the low-cost,reproducible,and large-scale printing of flexible and wearable electronic devices.

关键词： Graphene ink Fluid dynamics Screen printing Ion sensor Real-time monitoring

Evaluation of Heavy Rainfall Model Forecasts over the Korean Peninsula Using Different Physical Parameterization Schemes and Horizontal Resolution

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Advances in Atmospheric Sciences 2011年第6期28卷 1233-1245页

作者： jeong-Gyun PARK dong-Kyou LEE Atmospheric Sciences Program School of Earth and Environmental Sciences Seoul National University Seoul 151-747 Korea

In this study, the accuracy of a Pennsylvania State University–National Center for Atmospheric Research mesoscale model （PSU/NCAR MM5） for predicting heavy summer precipitation over the Korean Peninsula was investigated. A total of 1800 simulations were performed using this model for 30 heavy rainfall events employing four cumulus parameterization schemes （CPS）, two grid-scale resolvable precipitation schemes （GRS）, and two planetary boundary layer （PBL） schemes in three model resolutions （90 km, 30 km, and 10 km）. The heavy rainfall events were mesoscale convective systems developed under the influence of mid-latitude baroclinic systems with low-level moisture transport from the ocean. The predictive accuracy for maximum rainfall was approximately 80% for 10-km resolution and was 60% for 30-km resolution. The predictive accuracy for rainfall position extended to ～150 km from the observed position for both resolutions. Simulated rainfall was most sensitive to CPS, then to PBL schemes, and then to GRS. In general, the Grell （GR） scheme and the Anthes and Kuo （AK） scheme showed a better prediction capability for heavy rainfall than did the Betts-Miller （BM） scheme and the Kain-Fritsch （KF） scheme. The GR scheme also performed well in the 24-h and 12-h precipitation predictions： the parameterized convective rainfall in GR is directly related to synoptic-scale forcing. The models without CPS performed better for rainfall amounts but worse for rainfall position than those with CPS. The MM5 model demonstrated substantial predictive capacity using synoptic-scale initial conditions and lateral boundary data because heavy summer rainfall in Korea occurs in a strong synoptic-scale environment.

关键词： heavy rainfall mesoscale convection mesoscale model evaluation convective parameterization

Classification of normal and abnormal ECG records using lead convolutional neural network and rule inference

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Science China(Information Sciences) 2017年第7期60卷 265-267页

作者： Linpeng JIN jun dong Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of Sciences University of Chinese Academy of Sciences

With the improvement of living standards,more and more people pay attention to their own health problems and performing an ECG test is the preferred selection for preventing cardiovascular *** it is easy to sample ECG now,diagnostic conclusion cannot be made because of the lack of domain experts,especially in the basic community medical insurance system(BCMIS)of China.A feasible solution is to send ECG records to a cloud-computing platform monitored by ECG

关键词： ECG Classification of normal and abnormal ECG records using lead convolutional neural network and rule inference RI NPV than

Characterization of Microstructure of Permanent Mold Cast Zinc Alloy ZA27

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材料热处理学报 2004年第5期25卷 174-179页

作者： CHENTi-jun LIYuan-dong HAOYuan StateKeyLabofAdvancedNonferrousMaterials LanzhouUniversityofTechnologyLanzhouChina

The microstructure of permanent mold cast zinc alloy ZA27 was examined by SEM and TEM after natural aging for 18 months. It was found that the primary a’ phase, peritectic and eutectic phases all decomposed into the equilibrium well-formed a+r| lamellae or irregular a+T| structure through cellular reaction. The cell colonies nucleated on the interdendritic eutectic T| layer and grew into the primary dendrites, thus first making the phase in the dendrite edges decompose, and then the a’ phase in the dendrite cores. The products from the a’ phase appeared in regular lamellae rather than irregular particles. In addition, a fine, dense transitional phase a’m containing 27.8 mass% Al, with a fee crystal structure and lattice parameter of about 0.4013nm, formed in lamellae. Copper was preferentially concentrated in Zn-rich n phase and existed in the form of Cu-rich e phase (CuZo,) particles, with hep crystal structure and parameters a=0.274nm, c=0.429nm and c/a=l .567.

关键词：显微结构硬模铸造 ZA27合金 SEM TEM

Supersonic Cavity Based Combustion with Kerosene/Hydrogen Fuel

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Journal of Thermal Science 2015年第2期24卷 164-172页

作者： Rajarshi Das jeong Soo Kim Heuy dong Kim Department of Mechanical Engineering Andong National University School of Mechanical Engineering Pukyong National University

A comparative study with kerosene and hydrogen fuel in a model scramjet combustor has been carried out nu- merically. The effect of fuel-air equivalence ratio on the flow field properties in a cavity based mixing mechanism at a freestream Math number of 2.08 has been probed. The investigation has been carried out in a two dimension- al numerical model where a cavity of length to depth ratio of 2 is mounted on one of the walls of the flow channel The flow field shock structure is observed to change with the change in fuel-air equivalence ratio. Total pressure loss is observed to depend both on fuel air equivalence ratio and the fuel type. The spread of fuel in the test sec- tion shows marked variation with the equivalence ratio. Performance of injector location on the fuel-air mixing is also probed during the course of the investigation.

关键词： Scramjet fuel-air mixing kerosene hydrogen equivalence ratio

Neuroprotective Effects of Brain-Gut Peptides: A Potential Therapy for Parkinson’s Disease

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Neuroscience Bulletin 2019年第6期35卷 1085-1096页

作者： dong dong junxia Xie jun Wang Department of Physiology and Pathophysiology Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders and State Key Disciplines: Physiology Medical College of Qingdao University

Parkinson's disease(PD) is the second most common neurodegenerative disease and is typically associated with progressive motor and non-motor ***, dopamine replacement therapy is mainly used to relieve the motor symptoms, while its long-term application can lead to various complications and does not cure the disease. Numerous studies have demonstrated that many brain-gut peptides have neuroprotective effects in vivo and in vitro, and may be a promising treatment for PD. In recent years, some progress has been made in studies on the neuroprotective effects of some newly-discovered braingut peptides, such as glucagon-like peptide 1, pituitary adenylate cyclase activating polypeptide, nesfatin-1, and ghrelin. However, there is still no systematic review on the neuroprotective effects common to these peptides. Thus,here we review the neuroprotective effects and the associated mechanisms of these four peptides, as well as other brain-gut peptides related to PD, in the hope of providing new ideas for the treatment of PD and related clinical research.

关键词： Parkinson's disease Glucagon-like peptide 1 Pituitary adenylate cyclase activating polypeptide Nesfatin-1 Ghrelin

Analysis of optical emission spectroscopy data during silicon etching in SF_(6)/O_(2)/Ar plasma

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Plasma Science and Technology 2021年第12期23卷 117-127页

作者： dong Hwan KIM jeong Eun CHOI Sang Jeen HONG Department of Electronics Engineering Myongji University116 Myongji-roYongin-siGyeonggi-doRepublic of Korea

Silicon etching is an essential process in various applications,and a major challenge for etching process is anisotropic high aspect ratio etching *** etch profile is determined by the plasma parameters and process *** this study,the plasma state with each process parameters were analyzed through the optical emission spectroscopy(OES)plasma diagnostic sensor by both chemical and physical *** temperature and electron density were additionally acquired using the corona model with OES data that provides chemical species information,and the etch profile was evaluated through scanning electron microscope measurement *** results include changes in profile with gas ratio,bias power,and *** figure out that factors like ion energy and ion angular distribution as well as chemical reaction affect the anisotropic profile.

关键词： silicon etching profile optical emission spectroscopy plasma in-formation corona model