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Word Generative Grammar——an Extensible 6-element System:｛V_T,V_N,θ, L,S,P｝

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The Journal of china Universities of Posts and Telecommunications 2003年第2期10卷 27-33页

作者： CHEN Xu, WANG Zhi min, GAO Qing shi (information engineering school. university of science & technology, beijing.100083. P.R.china) 北京科技大学北京 100083

On the basis of formal grammar, this paper introduces operation set θ (e.g.,vector point multiply ·, vector couple multiply * , vector set multiply X, substitution H,function F, set plus ∪, et al.) and set of set' s types L (e.g., ordered set, continuous(descending) ordered set, unordered set, coupled set, coordinate, et al.), and generalizes them toother word types of natural language, thus presenting the generative grammar for words―anextensible 6-element formal system {V_T, V_N, θ, L, S, P}, and takeing time words in naturallanguage as example for detailed discussion. With the colorfulness of time words of naturallanguage, time words for different natural languages assume different meaning. Generative grammarfor time words can generate not only different time words, but also their semantics (Generativegrammar of Chomsky can only produce all right sentences instead of semantics), and then, generalizesthem to other word types, e.g., accurate measure words, adjectives, etc.

关键词： natural language formal system word generative grammar extensible6-element system

Level Set interface treatment and its application in Euler method

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science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 227-236页

作者： WU KaiTeng1,2,HAO Li3,WANG Cheng4 & ZHANG Li1,2 1 Numerical Simulation Sichuan Higher school.Key Laboratory,Neijiang Normal university,Neijiang 641112,china 2 College of Mathematics and information science,Neijiang Normal university,Neijiang 641112,china 3 College of science,beijing.university of Civil engineering and Architecture,beijing.100044,china 4 State Key Laboratory of Explosion science and technology,beijing.Institute of technology,beijing.100081,china Neijiang Normal university Numerical Simulation Sichuan Higher School Key Laboratory Neijiang China (GRID:grid.464376.4) (ISNI:***) Neijiang Normal university College of Mathematics and Information Science Neijiang China (GRID:grid.464376.4) (ISNI:***) beijing.university of Civil engineering and Architecture College of Science Beijing China (GRID:grid.411629.9) (ISNI:***) beijing.Institute of technology State Key Laboratory of Explosion Science and Technology Beijing China (GRID:grid.43555.32) (ISNI:***)

Level Set interface treatment method is introduced into Euler method,which is employed for interface treatment method for multi-materials. Combined with the ghost fluid method,the moving interface is tracked. Fifth-order WENO spatial discretization and third-order TVD Runge-Kutta time discretization methods are used. Shock-wave action on bubble,implosion and velocity field Shock effect bubbles; implosion and velocity field are simulated by means of LS-MMIC3D programmed by C++. Nu-merical results show that the Level Set interface treatment method is effective and feasible for multi-material interface treatment in comparison with the WENO method.

关键词： Euler method Level Set method shock-wave action on bubble implosion numerical simulation

High current density Sc2O3-W matrix dispenser cathode

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science china(information sciences) 2012年第1期55卷 98-105页

作者： WANG JinShu,ZHANG XiZhu,LIU Wei,WANG YiMan,ZHOU MeiLing&ZUO TieYong school.of Materials science and engineering,beijing.university of technology,beijing.100124,china school.of Materials science and engineering Beijing University of Technology

Sc2O3-W matrix dispenser cathodes have been prepared by powder metallurgy method and tested in Pierce electron *** emission current density can reach 72 A/cm2 at 900C and over 100 A/cm2 can be achieved at a temperature higher than *** emission improves and then keeps stable with time throughout the life testing period of 330 h at a continuous loading of 88 A/cm2pulsed current density with a pulse width of 10μs and duty cycle of 0.2%.The cathode surface is covered by a semiconductor multilayer composed of Ba,Sc and *** emission behavior of the cathode can be explained by a semiconductor model.

关键词： emission property Scandia doped tungsten cathode

Matrix calculation of high-dimensional cross product and its application in automatic recognition of the endmembers of hyperspectral imagary

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science china(information sciences) 2011年第1期54卷 197-203页

作者： GENG XiuRui1,ZHAO YongChao1,LIU SuHong2 & WANG FuXiang3 1Key Laboratory of technology in Geo-spatial information Processing and Application System, Institute of Electronics,Chinese Academy of sciences,beijing.100080,china 2State Key Laboratory of Remote Sensing science,Jointly Sponsored by beijing.Normal university and the Institute of Remote Sensing Applications of Chinese Academy of sciences, school.of Geography,beijing.Normal university,beijing.100875,china 3school.of Electronics and information engineering,Beihang university,beijing.100191,china Key Laboratory of technology in Geo-spatial information Processing and Application System Institute of Electronics Chinese Academy of Sciences State Key Laboratory of Remote Sensing science Jointly Sponsored by Beijing Normal University and the Instit

This paper gives the definition of the high-dimensional cross product and its calculation by extending the 3-D cross product definition into the high-dimensional vector *** on the properties of the cross product,the volume variance index(VVI)is proposed to be used in extracting automatically the endmembers of the hypherspectral imagery which eliminates the shortcoming of the traditional method of using simplex only where the extraction results were easily impacted by the abnormal pixels.A case study of endmembers extraction experiment using the VVI method with the AVIRIS data for Cuprite has shown a very good result.

关键词： endmember simplex hyperspectral imagery cross product

High-performance flexible semiconductor fibres for multi-scenario communication applications

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science china Materials 2024年第7期67卷 2363-2364页

作者： Qinghui Lin yang Li Guozhen Shen school.of information science and engineering University of JinanJinan 250022China school.of Microelectronics Shandong UniversityJinan 250101China school.of Integrated Circuits and Electronics beijing.Institute of technology Beijing 100081China

With the advances in the field of flexible fibre technology in recent years,a variety of flexible fibres with different preparation processes have emerged[1,2].However,most of the flexible fibres in the past have structural breaks,making them unsuitable for long-term use as wearable fabrics[3,4].Glass semiconductors are widely used in thermally stretched fibres due to their advantages such as controllable fluidity,but they suffer from electronic defects compared with crystalline semi conductors in electronic semiconductors such as silicon(Si)and germanium(Ge)[5].Obviously,the semiconductor component in flexible optic fibres is a key component in regulating their mechanical and electrical properties[6].

关键词： wear fibres fibre

Adaptive multi-channel Bayesian graph attention network for IoT transaction security

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Digital Communications and Networks 2024年第3期10卷 631-644页

作者： Zhaowei Liu Dong yang Shenqiang Wang Hang Su school.of Computer and Control engineering Yantai UniversityYantai264005China Department of Electronics Information and BioengineeringPolitecnico di MilanoMilan20133Italy

With the rapid advancement of 5G technology,the Internet of Things(IoT)has entered a new phase of appli-cations and is rapidly becoming a significant force in promoting economic *** to the vast amounts of data created by numerous 5G IoT devices,the Ethereum platform has become a tool for the storage and sharing of IoT device data,thanks to its open and tamper-resistant ***,Ethereum account security is necessary for the Internet of Things to grow quickly and improve people's *** modeling Ethereum trans-action records as a transaction network,the account types are well identified by the Ethereum account classifi-cation system established based on Graph Neural Networks(GNNs).This work first investigates the Ethereum transaction ***,experimental metrics reveal that the Ethereum transaction network is neither optimal nor even satisfactory in terms of accurately representing transactions per *** flaw may significantly impede the classification capability of GNNs,which is mostly governed by their *** work proposes an Adaptive Multi-channel Bayesian Graph Attention Network(AMBGAT)for Ethereum account clas-sification to address this *** uses attention to enhance node features,estimate graph topology that conforms to the ground truth,and efficiently extract node features pertinent to downstream *** extensive experiment with actual Ethereum transaction data demonstrates that AMBGAT obtains competitive performance in the classification of Ethereum accounts while accurately estimating the graph topology.

关键词： Internet of things Graph representation learning Node classification Security mechanism

Cascade recursion models of computing the temperatures of underground layers

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science china(Technological sciences) 2006年第Z2期49卷 30-38页

作者： HAN Liqun, BI Siwen & SONG Shixin school.of information engineering, beijing.technology and Business university, beijing.100037, china State Key Laboratory of Remote Sensing science, Institute of Remote Sensing Applications, Chinese Academy of sciences, beijing.100101, china beijing.Technol & Business Univ Sch Informat Engn Beijing 100037 Peoples R China Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China

An RBF neural network was used to construct computational models of the underground temperatures of different layers, using ground-surface parameters and the temperatures of various underground layers. Because series recursion models also enable researchers to use above-ground surface parameters to compute the temperatures of different underground layers, this method provides a new way of using thermal infrared remote sensing to monitor the suture zones of large areas of blocks and to research thermal anomalies in geologic structures.

关键词： RBF network, underground temperature, modeling, cascade, recursion.

Weakly supervised point cloud segmentation via deep morphological semantic information embedding

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CAAI Transactions on Intelligence technology 2024年第3期9卷 695-708页

作者： Wenhao Xue yang yang Lei Li Zhongling Huang Xinggang Wang Junwei Han Dingwen Zhang school.of Automation Northwestern Polytechnical UniversityXi'anChina Institute of Mechanical and Electrical engineering BeijingChina school.of Electronic information and Communications Huazhong University of Science and TechnologyWuhanChina

Segmenting the semantic regions of point clouds is a crucial step for intelligent agents to understand 3D *** supervised point cloud segmentation is highly desirable because entirely labelling point clouds is highly time-consuming and *** the low-costing labelling of 3D point clouds,the scene-level label is one of the most effortless label ***,due to the limitation of classifier discriminative capability and the orderless and structurless nature of the point cloud data,existing scene-level method is hard to transfer the semantic information,which usually leads to the under-activated or over-activated *** this end,a local semantic embedding network is introduced to learn local structural patterns and semantic ***,the proposed network contains graph convolution-based dilation and erosion embedding modules to implement‘inside-out’and‘outside-in’semantic information dissemination ***,the proposed weakly supervised learning framework could achieve the mutual propagation of semantic information in the foreground and *** experiments on the widely used ScanNet benchmark demonstrate the superior capacity of the proposed approach when compared to the current alternatives and baseline models.

关键词： artificial intelligence computer vision deep learning

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2, LIU Chang-hua2, ZHANG He-bing2 1. College of Resources science and technology, beijing.Normal university, beijing.100875, china 2. school.of Surveying and Land information engineering, Henan Polytechnic university, Jiaozuo 454000, china College of Resources science and technology Beijing Normal University Beijing 100875 China school.of Surveying and Land information engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine