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A Hybrid Method of Domain Lexicon Construction for Opinion Targets Extraction Using Syntax and Semantics

Journal of Computer Science & technology 2016年第3期31卷 595-603页

作者： Chun Liao Chong Feng Sen Yang He-Yan Huang Department of Computer Science and Technology Beijing Institute of Technology Beijing 100081 China Beijing Engineering Research Center of High Volume Language Information Processing and Cloud Computing Applications Beijing Institute of Technology Beijing 100081 China

Opinion targets extraction of Chinese microblogs plays an important role in opinion mining. There has been a significant progress in this area recently, especially the method based on conditional random field （CRF）. However, this method only takes lexicon-related features into consideration and does not excavate the implied syntactic and semantic knowledge. We propose a novel approach which incorporates domain lexicon with groups of syntactical and semantic features. The approach acquires domain lexicon through a novel way which explores syntactic and semantic information through Part- of-Speech, dependency structure, phrase structure, semantic role and semantic similarity based on word embedding. And then we combine the domain lexicon with opinion targets extracted from CRF with groups of features for opinion targets extraction. Experimental results on COAE2014 dataset show the outperformance of the approach compared with other well-known methods on the task of opinion targets extraction.

关键词： domain lexicon opinion targets extraction syntactic structure semantic role word embedding

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Effect of thickness variations of lithium niobate on insulator waveguide on the frequency spectrum of spontaneous parametric down-conversion

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Chinese Physics B 2021年第11期30卷 268-273页

作者： Guang-Tai Xue Xiao-Hui Tian Chi Zhang Zhenda Xie Ping Xu Yan-Xiao Gong Shi-Ning Zhu National Laboratory of Solid State Microstructures School of PhysicsSchool of Electronic Science and EngineeringCollege of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Institute for Quantum Information and State Key Laboratory of High Performance Computing College of ComputingNational University of Defense TechnologyChangsha 410073China

We study the effect of waveguide thickness variations on the frequency spectrum of spontaneous parametric downconversion in the periodically-poled lithium niobate on insulator(LNOI)*** analyze several variation models and our simulation results show that thickness variations in several nanometers can induce distinct effects on the central peak of the spectrum,such as narrowing,broadening,and *** also prove that the effects of positive and negative variations can be canceled and thus lead to a variation-robust feature and an ultra-broad *** study may promote the development of on-chip photon sources in the LNOI platform,as well as opens up a way to engineer photon frequency state.

关键词： lithium niobate on insulator spontaneous parametric down-conversion waveguide thickness variation frequency spectrum

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Strengthening-softening transition and maximum strength in Schwarz nanocrystals

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Nano Materials Science 2024年第3期6卷 320-328页

作者： Hanzheng Xing Jiaxi Jiang Yujia Wang Yongpan Zeng Xiaoyan Li Center for Advanced Mechanics and Materials Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijing100084China Institute of High Performance Computing(IHPC) Agency for ScienceTechnology and Research(A*STAR)Singapore138632Singapore

Recently,a Schwarz crystal structure with curved grain boundaries(GBs)constrained by twin-boundary(TB)networks was discovered in nanocrystalline Cu through experiments and atomistic *** Cu with nanosized Schwarz crystals exhibited high strength and excellent thermal ***,the grainsize effect and associated deformation mechanisms of Schwarz nanocrystals remain ***,we performed large-scale atomistic simulations to investigate the deformation behaviors and grain-size effect of nanocrystalline Cu with Schwarz *** simulations showed that similar to regular nanocrystals,Schwarz nanocrystals exhibit a strengthening-softening transition with decreasing grain *** critical grain size in Schwarz nanocrystals is smaller than that in regular nanocrystals,leading to a maximum strength higher than that of regular *** simulations revealed that the softening in Schwarz nanocrystals mainly originates from TB migration(or detwinning)and annihilation of GBs,rather than GB-mediated processes(including GB migration,sliding and diffusion)dominating the softening in regular *** analyses of simulation data further showed that compared with those in regular nanocrystals,the GB-mediated processes in Schwarz nanocrystals are suppressed,which is related to the low volume fraction of amorphous-like GBs and constraints of TB *** smaller critical grain size arises from the suppression of GB-mediated processes.

关键词： Schwarz nanocrystal Curved grain boundary Atomistic simulation Grain size effect Maximum strength

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On the construction of virtual multicast backbone for wireless ad hoc networks

On the construction of virtual multicast backbone for wirele...

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2004 IEEE International Conference on Mobile Ad-Hoc and Sensor Systems

作者： Wu, Ya-Feng Xu, Yin-Long Chen, Guo-Liang Wang, Kun Department of Computer Science and Technology University of Science and Technology of China National High Performance Computing Center Hefei

ISBN: (纸本)0780388151

With the proliferation of portable computing devices and ascending popularity of group-oriented computing, wireless ad hoc network multicasting remains a challenging research subject. While Virtual Multicast Backbone (VMS) structure are commonly used in current multicast protocols, this paper focuses on the construction of the optimal VMB with the fewest forwarding nodes to decrease overhead and cost, due to the scarce resource in ad hoc networks. Instead of conventional Steiner tree model, the optimal shared VMB in ad hoc networks is modeled as Minimum Steiner Dominating Set (MSCDS) in Unit-Disk Graphs (UDG), which is NP-hard. A performance evaluation of flooding for MSCDS is given and a One-hop Algorithm is proposed with an approximation ratio of at most 10. To adapt various network scenarios, this paper further presents a fully distributed d-hop algorithm also with a constant approximation ratio, which organizes multicast nodes to form a hierarchical VMB. Based on the hierarchical structure, this paper proposes some approaches to maintain and update VMB, and gives a security framework to exclude malicious nodes from multicast groups. Simulation results show that the proposed algorithms perform very well. ©2004 IEEE.

关键词： Wireless telecommunication systems

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Aqueous and mechanical exfoliation, unique properties, and theoretical understanding of MoO3 nanosheets made from free-standing a-MoO3 crystals： Raman mode softening and absorption edge blue shift

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Nano Research 2018年第3期11卷 1193-1203页

作者： Hongfei Liu Yongqing Cai Mingyong Han Shifeng Guo Ming Lin Meng Zhao Yongwei Zhang Dongzhi Chi Institute of Materials Research and Engineering (IMRE) A＊STAR (Agency for Science Technology and Research) 2 Eusionopolis Way Singapore 138634 Singapore Institute of High Performance Computing (IHPC) A ＊STAR (Agency for Science Technology and Research) 1 Fusionopolis Way Singapore 138632 Singapore

Crystalline α-MoO3 belts consisting of nanosheets stacked along their [010] axes were synthesized via thermal vapor transport of MoO3 powders at elevated temperatures. The MoO3 belts were millimeters in length along their [001] axes and tens to hundreds of micrometers in width along their [100] axes. Mechanical and aqueous exfoliations of the belts to form two-dimensional （2D） nanosheets were processed via the scotch-tape and bovine serum albumin （BSA） assisted methods, respectively. Upon scotch-tape exfoliation, the Raman features of MoO3 exhibited monotonic decreases in intensity as the thickness was gradually fell to approach that of a 2D nanosheet. Most Raman features eventually disappeared when a monolayer nanosheet was produced, except for the Mo-O-Mo stretching mode （Ag） at - 818 cm^-1, which was accompanied by mode-softening of up to 5 cm^-1 This mode softening, hitherto not reported for 2D α-MoO3 nanosheets, can be attributed to lattice relaxations that are validated here via theoretical density functional perturbation theory calculations. The BSA-assisted exfoliation products exhibited a blueshift in the α-MoO3 nanosheet absorption edge; they also revealed an absorption peak at 3.98 eV that can be attributed to their intrinsic exciton absorptions. These observations, together with the facile synthesis of high-purity α-MoO3 crystals, illuminate the possibility of further 2D α-MoO3 nanosheet production and lattice dynamic studies.

关键词： α-MoO3 two-dimensionalmaterials exfoliations lattice vibrationaldynamics micro-Raman scattering

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Unravelling the metal borides evolution in the transient liquid phase bonding of Ni-based alloys via high-throughput transmission electron microscopy and first-principles thermo-kinetic calculations

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Journal of Materials Science & technology 2021年第26期85卷 118-128页

作者： Kewu Bai Ming Lin Institute of High Performance Computing Agency for ScienceTechnology and ResearchFusionopolis Way#16-16 ConnexisSingapore 138632Singapore Institute of Materials Research and Engineering(IMRE) Fusionopolis WayInnovis#08-03Singapore 138634Singapore

The understanding of temperature and time-dependent metal borides precipitation/dissolution is crucial for the design of the transient liquid phase(TLP)bonding process of Ni-based *** however remains elusive despite substantial research efforts for many years mainly owing to the uncertainty on the precipitated metal borides and the complex thermo-kinetics in the *** this paper,we have unambiguously constructed the micro/nano scale map of the precipitated metal borides in the TLP bonded Ni-based Inconel 718 superalloy via a high-throughput transmission electron microscopy(TEM)*** types of metal borides were found to precipitate in the diffusion affected zone(DAZ)when the isothermal solidification is *** are the M_(5)B_(3)with stacking faults,Ti-rich M_(3)B4,and Nb-rich M_(3)B4 at the grain boundaries as well as single-crystalline M_(5)B_(3)and M_(3)B2 inside the ***,the crystal structure of the faulted M_(5)B_(3)was rationalized by a hybrid modelling approach integrating firstprinciples calculation and TEM *** sublattice model,with the optimized thermodynamic model parameters,was used to reproduce the metal borides precipitation map in the TLP process using DICTRA *** with multiscale simulation and experimental data,the present work built a modified thermo-kinetic model,which enables the design of the TLP bonding process of Ni-based alloys that often involves complicated time-tempe rature schedules and the precipitation/dissolution of a variety of diffe rent *** strategy can be applied to the design of the brazing process of other alloys or hybrid materials such as ceramics and metal.

关键词： Ni-based superalloy Transmission electron microscopy Transient liquid bonding Precipitation Kinetics

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Simulation of the Quantum Key Distribution Algorithm Using the Intel Quantum SDK 13

Simulation of the Quantum Key Distribution Algorithm Using t...

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13th International Conference on Advanced Computer Information Technologies, ACIT 2023

作者： Gambo, Yaknan John Shinde, Tejas Rasch, Kevin Liebelt, Helena Li, Rui Deggendorf Institute of Technology High Performance Computing and Quantum Computing Deggendorf Germany Quantum Computing Research Intel Inc HillsboroOR United States Deggendorf Institute of Technology Department of Computer Science Deggendorf Germany

Information security is an important fabric of our world today. Technologies used in the development of information security have constantly been evolving in response to new threats. Cryptographic algorithms like the RSA, DSA, AES etc. are currently being used in securing information even over insecure channels. The coming of quantum computers has now posed a great threat to classical cryptosystems which can be broken in polynomial time thanks to Shor's algorithm. A good hacker with good quantum computing power can break into encrypted messages easily. The Quantum Key Distribution (QKD) algorithm based on the BB84 protocol provides a solution to this problem. It makes it possible for communicating parties to exchange secret keys securely before a conversation can ensue. Verifying if these keys have been tampered with is a good first step to start before any other. QKD technology has made it possible to exchange these keys via an insecure channel and lets communicating parties know if an eavesdropper has tempered with the message. In this work, we discuss the QKD algorithm and simulated it on the newly released Intel quantum SDK. © 2023 IEEE.

关键词： Quantum cryptography

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A new approach for implementing the arithmetic Fourier transform (AFT) 4

A new approach for implementing the arithmetic Fourier trans...

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4th International Conference/Exhibition on high performance computing in the Asia-Pacific Region, HPC-Asia 2000

作者： Zhang, Xianchao Wan, Yingyu Chen, Guoliang National High Performance Computing Center at Hefei University of Science and Technology of China Hefei230027 China

ISBN: (纸本)0769505902

The arithmetic Fourier transform (AFT) is an important Fourier analysis technique. Since AFT algorithms require lots of non-uniform samples, zero-order interpolation is used for implementing AFT, but this method can produce significant errors. To reduce the errors, over-sampling is needed, meaning the sampling rate should be a number of times the Nyquist rate. The over-sampling problem is the main drawback of AFT. In this paper a new method for implementing AFT with no need for over-sampling is presented. This method gains nearly the same effect as the method using over-sampling, so it makes it possible for us to implement AFT with sampling at the Nyquist rate. © 2000 IEEE.

关键词： Fourier analysis

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Data-driven approach for generating colormaps of scientific simulation data 14

Data-driven approach for generating colormaps of scientific ...

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14th IADIS International Conference Computer Graphics, Visualization, Computer Vision and Image Processing 2020, CGVCVIP 2020 and 5th IADIS International Conference Big Data Analytics, Data Mining and Computational Intelligence 2020, BigDaCI 2020 and 9th IADIS International Conference Theory and Practice in Modern computing 2020, TPMC 2020, Part of the 14th Multi Conference on Computer Science and Information Systems, MCCSIS 2020

作者： Cao, Yi Wang, Xiaohua Wang, Huawei Ai, Zhiwei Xia, Fang High Performance Computing Center Institute of Applied Physics and Computational Mathematics Beijing China CAEP Software Center for High Performance Numerical Simulation Beijing China

ISBN: (纸本)9789898704214

The colormap plays important roles in the exploration, analysis, and discovery of scientific data. Datasets generated by real-world simulation applications are becoming increasingly more complex: the distribution of the variable values within the data is often extremely uneven and accompanied by high levels of data noise. The heterogeneity of these data characteristics presents rich information about physical laws as well as technical challenges for colormap of visualization. Most default colormaps are defined by linearly interpolating dataset values and cannot be adapted to convey the physical meaning behind complicated data. In this paper, we introduce a data-driven approach for generating colormaps of scientific simulation data, that can overcome the visualization problems using noise-reduction-based parameter tuning of color control points and a wave-like colormap enhancement in brightness. Several real-world simulation data are used to verify the effectiveness of our proposed method, which means that our method could help domain scientists understand complicated data more clearly and quickly. © Proceedings of the 14th IADIS International Conference Computer Graphics, Visualization, Computer Vision and Image Processing 2020, CGVCVIP 2020 and Proceedings of the 5th IADIS International Conference Big Data Analytics, Data Mining and Computational Intelligence 2020, BigDaCI 2020 and Proceedings of the 9th IADIS International Conference Theory and Practice in Modern computing 2020, TPMC 2020 - Part of the 14th Multi Conference on Computer Science and Information Systems, MCCSIS 2020. All rights reserved.

关键词： Data visualization

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performance prediction based on hierarchy parallel features captured in multi-processing system 09

Performance prediction based on hierarchy parallel features ...

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18th ACM International Symposium on high performance Distributed computing, HPDC 09, Co-located with the 2009 International Symposium on high performance Distributed computing Conference, HPDC'09

作者： Jiaxin, Li Feng, Shi Ning, Deng Qi, Zuo High Performance Embedded Computing Lab. School of Computer Science and Technology Beijing Institute of Technology China

ISBN: (纸本)9781605585871

As the computing ability of high performance computers are improved by increasing the number of computing elements, how to utilize the available computing resources becomes an important issue. Different strategies to solve an problem based on a multi-processing system can bring about distinct performance. In this paper, we propose a method to predict the performance of parallel applications. The method describes the parallel features of the multi-processing systems in a hierarchy way, and evaluates solutions based on the description. In this way, programmers can find the better solution of an application before real programming.

关键词： Forecasting

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