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Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： Xin FENG Liaoliang KE yang gao College of Science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are *** electro-elastic model is developed to investigate the anti-plane strain problem of Love wave *** introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated *** the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary *** examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect

A measuring method of effects of herbs based on classification used for intelligent calculation of efficacies of prescriptions

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Science china(Information Sciences) 2010年第10期53卷 2047-2061页

作者： gao QuanQuan 1 & REN TingGe 2 1 academy of Math & Systems, chinese academy of Sciences, beijing 100190, china 2 beijing University of chinese Medicine, beijing 100029, china 1. academy of Math & Systems Chinese Academy of Sciences Beijing 100190 China2. Beijing University of Chinese Medicine Beijing 100029 China

It is important to translate dosage of each medical herb in a prescription into intensity of its effects measured by mathematical models. In this paper, we present intelligent calculational algorithms on efficacies of prescriptions of chinese Medicine (CM), study "how curative effects of any herb depend on dosage" when constructing CM intelligent systems, and discuss relevant issues and definitions. In order to measure intensities of effects of all herbs reasonably, the natural classification method is proposed to classify herbs into 3. natural classes according to their dosage ranges using the knowledge of CM dosage and distribution rules of herbs. Then the 3. natural classes are clustered to 6 basic classes reflecting characteristic attributes of various herbs. Based on the results of classified herbs, a set of nonlinear measuring functions of intensities of effects is designed for various basic classes. These functions have been embedded in our intelligent calculation system of efficacies of prescriptions. The effects of 560 herbs and curative efficacies of more than 1000 prescriptions derived from "ShangHan Lun", "JinGui YaoLue", "Ming Jia Yi An", etc., have been calculated and discovered successfully. It is proved that the accuracy of theses results by these models has been obviously enhanced.

关键词： intelligent calculation mathematical modeling measuring method efficacies of prescriptions

Precise orbit determination for low Earth orbit satellites using GNSS:Observations,models,and methods

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Astrodynamics 2024年第3期8卷 349-374页

作者： Xinyuan Mao Wenbing Wang yang gao Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing100094China University of chinese academy of Sciences Beijing101408China

Spaceborne global navigation satellite system(GNSS)has significantly revolutionized the development of autonomous orbit determination techniques for low Earth orbit satellites for *** a state-of-the-art combination of GNSS observations and satellite dynamics,the absolute orbit determination for a single satellite reached a precision of 1 *** orbit determination(i.e.,precise baseline determination)for the dual satellites reached a precision of 1 *** paper reviews the recent advancements in GNSS products,observation processing,satellite gravitational and non-gravitational force modeling,and precise orbit determination *** key aspects have increased the precision of the orbit determination to fulfill the requirements of various scientific ***,recommendations are made to further investigate multi-GNSS combinations,satellite high-fidelity geometric models,geometric offset calibration,and comprehensive orbit determination strategies for satellite constellations.

关键词： low Earth orbit(LEO) precise orbit determination(POD) precise baseline determination(PBD) global navigation satellite system(GNSS) multi-GNSS satellite constellation

Construction and evaluation of a novel end-column amperometric detection system for electrophoresis microchips

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Science china Chemistry 2010年第1期53卷 250-256页

作者： CHEN ZhiFeng1,gao YunHua2,WANG Li3.CHU XiaoGang1 1chinese academy of Inspection and Quarantine,{3. 100123.china 2Technical Institute of Physics and Chemistry,chinese academy of Sciences,beijing 100190,china 3.3. Institute of Labour Protection,{3. 100054,china 1. chinese academy of Inspection and Quarantine Beijing 100123 China2. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China3. Beijing Institute of Labour Protection Beijing 100054 China

A set of integrated end-column amperometric detection system has been developed,onto which an electrophoresis microchip can be conveniently *** machined by a piece of transparent organic glass,the system consists of an electrophoresis microchip platform and an amperometric detection reservoir,in which the microchip can be fixed onto the platform by microchip grooves and with stainless steel *** detection electrode can be directly fixed in the amperometric detection reservoir by screws and *** dopamine as the model analyte,we take platinum disc electrodes with different diameters of 100 μm,3.0 μm and 500 μm and a carbon fiber electrode with the diameter of 240 μm as the working electrode,all of which accomplish sensitive *** detection parameters of the system are optimized with the carbon fiber *** detection results show that in the electrochemical cleaning procedure,the relative deviations of 3.2% and 0.5% for the peak current and retention time,respectively,can be obtained for the successive detections of 100 μM dopamine,and the limit of detection for dopamine can reach 0.4 μM(S/N = 3..This system is small,but its performance of detection is stable and sensitive,and the replacement of its working electrodes is convenient,so it is very suitable as a universal platform of end-column amperometric detection for electrophoresis microchips.

关键词： electrophoresis microchip amperometric detection dopamine evaluation

Geoscience Frontiers 2023.Annual Convention

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Geoscience Frontiers 2024年第3期15卷 484-487页

作者： Fei gao Lily Wang Yongqiang yang Geoscience Frontiers Journal CenterChina University of Geosciences(Beijing)Beijing 100083China

The 2023.Geoscience Frontiers Annual Convention was held at Niigata,Japan during 7-12 October 2023.together with 2023.IAGR Annual Convention and 20th International Conference on Gondwana to *** grand event assembled over 200 participants from several countries including china,Canada,India,Italy,Japan,Netherlands,Poland,Russia,South Korea,South Africa,Sri Lanka,Vietnam,United Kingdom,and United State of America.

关键词： Canada Convention Vietnam

Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020

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Journal of Mountain Science 2024年第9期21卷 3031-3046页

作者： gao Bing LIU Enqin yang yang yang Man YAO yang GUAN Lei FENG Yiwen College of Geography and Planning Chengdu University of TechnologyChengdu 610059China Key Laboratory of Smart Earth Beijing 100029China Sichuan Provincial Soil and Water Conservation Ecological Environment Monitoring Station Chengdu 610041China College of Earth and Planetary Sciences Chengdu University of TechnologyChengdu 610059China

Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige ***,the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain ***,clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the ***,we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI)as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the *** find a tendency of vegetation greening from 2001 to 2020,with significant greening accounting for 21.44%of the entire ***,browning area expanded rapidly after *** temperatures are the primary driver of vegetation changes in the Zoige *** variations and human activities were responsible for 65.57%and 3..43.of vegetation greening,and 3..14%and 60.86%of vegetation browning,respectively,with browning concentrated along the Yellow,Black and White *** to 2001-2010,the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020.

关键词： Vegetation change Climate change Residual trend analysis Geodetector Human activities Zoige plateau

Network Configuration Entity Extraction Method Based on Transformer with Multi-Head Attention Mechanism

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Computers, Materials & Continua 2024年第1期78卷 735-757页

作者： yang yang Zhenying Qu Zefan Yan Zhipeng gao Ti Wang State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China Product Development Department China Unicom Smart City Research InstituteBeijing100044China

Nowadays,ensuring thequality of networkserviceshas become increasingly *** are turning toknowledge graph technology,with a significant emphasis on entity extraction in the identification of device *** research paper presents a novel entity extraction method that leverages a combination of active learning and attention ***,an improved active learning approach is employed to select the most valuable unlabeled samples,which are subsequently submitted for expert *** approach successfully addresses the problems of isolated points and sample redundancy within the network configuration sample *** the labeled samples are utilized to train the model for network configuration entity ***,the multi-head self-attention of the transformer model is enhanced by introducing the Adaptive Weighting method based on the Laplace mixture *** enhancement enables the transformer model to dynamically adapt its focus to words in various positions,displaying exceptional adaptability to abnormal data and further elevating the accuracy of the proposed *** comparisons with Random Sampling(RANDOM),Maximum Normalized Log-Probability(MNLP),Least Confidence(LC),Token Entrop(TE),and Entropy Query by Bagging(EQB),the proposed method,Entropy Query by Bagging and Maximum Influence Active Learning(EQBMIAL),achieves comparable performance with only 40% of the samples on both datasets,while other algorithms require 50% of the ***,the entity extraction algorithm with the Adaptive Weighted Multi-head Attention mechanism(AW-MHA)is compared with BILSTM-CRF,Mutil_Attention-Bilstm-Crf,Deep_Neural_Model_NER and BERT_Transformer,achieving precision rates of 75.98% and 98.3.% on the two datasets,*** tests demonstrate the statistical significance and effectiveness of the proposed algorithms in this paper.

关键词： Entity extraction network configuration knowledge graph active learning transformer

The Lightweight Edge-Side Fault Diagnosis Approach Based on Spiking Neural Network

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Computers, Materials & Continua 2024年第6期79卷 4883-4904页

作者： Jingting Mei yang yang Zhipeng gao Lanlan Rui Yijing Lin State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China

Network fault diagnosis methods play a vital role in maintaining network service quality and enhancing user experience as an integral component of intelligent network *** the unique characteristics of edge networks,such as limited resources,complex network faults,and the need for high real-time performance,enhancing and optimizing existing network fault diagnosis methods is ***,this paper proposes the lightweight edge-side fault diagnosis approach based on a spiking neural network(LSNN).Firstly,we use the Izhikevich neurons model to replace the Leaky Integrate and Fire(LIF)neurons model in the LSNN *** neurons inherit the simplicity of LIF neurons but also possess richer behavioral characteristics and flexibility to handle diverse data *** by Fast Spiking Interneurons(FSIs)with a high-frequency firing pattern,we use the parameters of ***,inspired by the connection mode based on spiking dynamics in the basal ganglia(BG)area of the brain,we propose the pruning approach based on the FSIs of the BG in LSNN to improve computational efficiency and reduce the demand for computing resources and energy ***,we propose a multiple iterative Dynamic Spike Timing Dependent Plasticity(DSTDP)algorithm to enhance the accuracy of the LSNN *** on two server fault datasets demonstrate significant precision,recall,and F1 improvements across three diagnosis ***,lightweight indicators such as Params and FLOPs significantly reduced,showcasing the LSNN’s advanced performance and model *** conclude,experiment results on a pair of datasets indicate that the LSNN model surpasses traditional models and achieves cutting-edge outcomes in network fault diagnosis tasks.

关键词： Network fault diagnosis edge networks Izhikevich neurons pruning dynamic spike timing dependent plasticity learning

Multistate transition and coupled solid-liquid modeling of motion process of long-runout landslide

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2694-2714页

作者： yang gao Yueping Yin Bin Li Han Zhang Weile Wu Haoyuan gao Institute of Geomechanics Chinese Academy of Geological SciencesChina Geological SurveyBeijing100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing100081China china Institute of Geological Environment Monitoring China Geological SurveyBeijing100081China School of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

The recognition,repetition and prediction of the post-failure motion process of long-runout landslides are key scientific problems in the prevention and mitigation of geological *** this study,a new numerical method involving LPF3. based on a multialgorithm and multiconstitutive model was proposed to simulate long-runout landslides with high precision and *** following results were obtained:(a)The motion process of landslides showed a steric effect with mobility,including gradual disintegration and *** sliding mass can be divided into three states(dense,dilute and ultradilute)in the motion process,which can be solved by three dynamic regimes(friction,collision,and inertial);(b)Coupling simulation between the solid grain and liquid phases was achieved,focusing on drag force influences;(c)Different algorithms and constitutive models were employed in phase-state *** volume fraction is an important indicator to distinguish different state types and solid‒liquid *** flume experimental results were favorably validated against long-runout landslide case data;and(d)In this method,matched dynamic numerical modeling was developed to better capture the realistic motion process of long-runout landslides,and the advantages of continuum media and discrete media were combined to improve the computational accuracy and *** new method can reflect the realistic physical and mechanical processes in long-runout landslide motion and provide a suitable method for risk assessment and pre-failure prediction.

关键词： Long-runout landslide Multistate transition Mixed solid‒liquid flow Post-failure process Numerical simulation