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Uncertainty relations in the presence of quantum memory for mutually unbiased measurements

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Physical Review A 2018年第3期98卷 032329-032329页

作者： Kun Wang Nan Wu Fangmin Song State Key Laboratory for Novel Software Technology Department of Computer Science and Technology Nanjing University Nanjing 210093 China

In a work by Berta et al. [Phys. Rev. A 90, 062127 (2014)], uncertainty relations in the presence of quantum memory were formulated for mutually unbiased bases using conditional collision entropy. In this paper, we generalize their results to the mutually unbiased measurements. Our primary result is an equality between the amount of uncertainty for a set of measurements and the amount of entanglement of the measured state, both of which are quantified by the conditional collision entropy. Implications of this equality relation are discussed. We further show that similar equality relations can be obtained for generalized symmetric informationally complete measurements. We also derive an interesting equality for arbitrary orthogonal basis of the space of Hermitian, traceless operators.

关键词： Entanglement detection Quantum correlations in quantum information Quantum memories

swTVM: Towards Optimized Tensor Code Generation for Deep Learning on Sunway Many-Core Processor

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arXiv 2019年

作者： Li, Mingzhen Liu, Changxi Liao, Jianjin Zheng, Xuegui Yang, Hailong Sun, Rujun Xu, Jun Gan, Lin Yang, Guangwen Luan, Zhongzhi Qian, Depei School of Computer Science and Engineering Beihang University Beijing China State Key Laboratory of Software Development Environment Beijing China National University of Singapore Singapore Singapore State Key Laboratory of Mathematical Engineering and Advanced Computing Wuxi China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China Department of Computer Science and Technology Tsinghua University Beijing China

The flourish of deep learning frameworks and hardware platforms has been demanding an efficient compiler that can shield the diversity in both software and hardware in order to provide application portability. Among the existing deep learning compilers, TVM is well known for its efficiency in code generation and optimization across diverse hardware devices. In the meanwhile, the Sunway many-core processor renders itself as a competitive candidate for its attractive computational power in both scientific computing and deep learning workloads. This paper combines the trends in these two directions. Specifically, we propose swTVM that extends the original TVM to support ahead-of-time compilation for architecture requiring cross-compilation such as Sunway. In addition, we leverage the architecture features during the compilation such as core group for massive parallelism, DMA for high bandwidth memory transfer and local device memory for data locality, in order to generate efficient codes for deep learning workloads on Sunway. The experiment results show that the codes generated by swTVM achieves 1.79× on average compared to the state-of-the-art deep learning framework on Sunway, across six representative benchmarks. This work is the first attempt from the compiler perspective to bridge the gap of deep learning and Sunway processor particularly with productivity and efficiency in mind. We believe this work will encourage more people to embrace the power of deep learning and Sunway many-core processor. Copyright © 2019, The Authors. All rights reserved.

关键词： Program compilers

Transferable E-Cash System with Arbitrarily Spending Order

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Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of technology 2019年第3期39卷 283-289页

作者： Zhang, Jiang-Xiao Feng, Chun-Hui Ma, Jin-Xin Zhang, Bin Xu, Chang Li, Zhou-Jun Dang, Ying Mathematics and Information Technology Institute Xingtai University XingtaiHebei054001 China China Information Technology Security Evaluation Center Beijing100191 China School of Computer Science & Technology Beijing Institute of Technology Beijing100081 China State Key Laboratory of Software Development Environment Beihang University Beijing100191 China Xingtai Medical College XingtaiHebei054000 China

There exist some problems such that the user spending order is fixed in the transferable E-cash system, and the transferable number is restricted. Using the Groth-Sahai proof system, Ghadafi group blind signature and commitment to commitment, a transferable E-cash system of equal length with optimal anonymity and arbitrarily spending order was designed in a standard model. It was arranged that, based on the commitment to commitment, the users could compress the transferable serial number, and the length of the E-cash could be constant in the spending protocol, based on the Ghadafi group blind signature, the arbitrarily spending order could be achieved. Finally, the security of the transferable E-cash system was verified in the standard model. Results show its unforgeability, anonymity, identification of double spender and exculpability. © 2019, Editorial department of Transaction of Beijing Institute of technology. All right reserved.

关键词： Authentication

An empirical study on constraint optimization techniques for test generation

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science China(Information sciences) 2017年第1期60卷 69-83页

作者： Zhiyi ZHANG Zhenyu CHEN Ruizhi GAO Eric WONG Baowen XU State Key Laboratory for Novel Software Technology Nanjing University Department of Computer Science University of Texas at Dallas

Constraint solving is a frequent, but expensive operation with symbolic execution to generate tests for a program. To improve the efficiency of test generation using constraint solving, four optimization techniques are usually applied to existing constraint solvers, which are constraint independence, constraint set simplification, constraint caching, and expression rewriting. In this paper, we conducted an empirical study, using these four constraint optimization techniques in a well known test generation tool KLEE with 77 GNU Coreutils applications, to systematically investigate how these optimization techniques affect the efficiency of test generation. The experimental results show that these constraint optimization techniques as well as their combinations cannot improve the efficiency of test generation significantly for ALL-SIZED programs. Moreover, we studied the constraint optimization techniques with respect to two static metrics, lines of code(LOC) and cyclomatic complexity(CC), of programs. The experimental results show that the "constraint set simplification" technique can improve the efficiency of test generation significantly for the programs with high LOC and CC values. The"constraint caching" optimization technique can improve the efficiency of test generation significantly for the programs with low LOC and CC values. Finally, we propose four hybrid optimization strategies and practical guidelines based on different static metrics.

关键词： test generation symbolic execution constraint solving constraint optimization static metric

F2A2: Flexible Fully-decentralized Approximate Actor-critic for Cooperative Multi-agent Reinforcement Learning

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arXiv 2020年

作者： Li, Wenhao Jin, Bo Wang, Xiangfeng Yan, Junchi Zha, Hongyuan School of Data Science The Chinese University of Hong Kong Shenzhen China Shenzhen Institute of Artificial Intelligence and Robotics for Society Shenzhen518172 China School of Software Engineering Shanghai Research Institute for Intelligent Autonomous Systems Tongji University Shanghai201804 China School of Computer Science and Technology Key Laboratory of Mathematics and Engineering Applications Ministry of Education East China Normal University Shanghai200062 China Department of Computer Science and Engineering Key Laboratory of Artificial Intelligence Ministry of Education Shanghai Jiao Tong University Shanghai200240 China

Traditional centralized multi-agent reinforcement learning (MARL) algorithms are sometimes unpractical in complicated applications due to non-interactivity between agents, the curse of dimensionality, and computation complexity. Hence, several decentralized MARL algorithms are motivated. However, existing decentralized methods only handle the fully cooperative setting where massive information needs to be transmitted in training. The block coordinate gradient descent scheme they used for successive independent actor and critic steps can simplify the calculation, but it causes serious bias. This paper proposes a flexible fully decentralized actor-critic MARL framework, which can combine most of the actor-critic methods and handle large-scale general cooperative multi-agent settings. A primal-dual hybrid gradient descent type algorithm framework is designed to learn individual agents separately for decentralization. From the perspective of each agent, policy improvement and value evaluation are jointly optimized, which can stabilize multi-agent policy learning. Furthermore, the proposed framework can achieve scalability and stability for the large-scale environment. This framework also reduces information transmission by the parameter sharing mechanism and novel modeling-other-agents methods based on theory-of-mind and online supervised learning. Sufficient experiments in cooperative Multiagent Particle Environment and StarCraft II show that the proposed decentralized MARL instantiation algorithms perform competitively against conventional centralized and decentralized methods. Copyright © 2020, The Authors. All rights reserved.

关键词： Gradient methods

SG-PBFT: A secure and highly efficient blockchain PBFT Consensus Algorithm for internet of vehicles

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arXiv 2021年

作者： Xu, Guangquan Liu, Yihua Xing, Jun Luo, Tao Gu, Yonghao Liu, Shaoying Zheng, Xi Vasilakos, Athanasios V. The Big Data School Qingdao Huanghai University Qingdao266427 China College of Intelligence and Computing Tianjin University Tianjin300350 China The International Engineering Institute Tianjin University Tianjin300350 China The College of Intelligence and Computing Tianjin University Tianjin Tianjin300350 China The school of Computer Science Beijing University of Posts and Telecommunications Beijing100876 China The Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and Telecommunications Beijing100876 China School of Informatics and Data Science Hiroshima University Japan The Department of Computing Macquarie University SydneyNSW2109 Australia The University of Technology Sydney Australia The Fuzhou University Fuzhou China Lulea University of Technology Lulea Sweden

The Internet of Vehicles (IoV) is an application of the Internet of things (IoT). It faces two main security problems: (1) the central server of the IoV may not be powerful enough to support the centralized authentication of the rapidly increasing connected vehicles, (2) the IoV itself may not be robust enough to single-node attacks. To solve these problems, this paper proposes SG-PBFT: a secure and highly efficient PBFT consensus algorithm for Internet of Vehicles, which is based on a distributed blockchain structure. The distributed structure can reduce the pressure on the central server and decrease the risk of single-node attacks. The SG-PBFT consensus algorithm improves the traditional PBFT consensus algorithm by using a score grouping mechanism to achieve a higher consensus efficiency. The experimental result shows that our method can greatly improve the consensus efficiency and prevent single-node attacks. Specifically, when the number of consensus nodes reaches 1000, the consensus time of our algorithm is only about 27% of what is required for the state-of-the-art consensus algorithm (PBFT). Our proposed SG-PBFT is versatile and can be used in other application scenarios which require high consensus efficiency. Copyright © 2021, The Authors. All rights reserved.

关键词： Internet of things

R-LDA: Profiling RDF Datasets Using Knowledge-Based Topic Modeling

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R-LDA: Profiling RDF Datasets Using Knowledge-Based Topic Mo...

International Conference on Semantic Computing

作者： Seyedamin Pouriyeh Mehdi Allahyaril Gong Cheng Hamid Reza Arabnia Krys Kochut Maurizio Atzori Information Technology Department Kennesaw State University Marietta GA USA Computer Science Department Georgia Southern University Statesboro USA National Key Laboratory for Novel Software Technology Nanjing University Nanjing China Computer Science Department University of Georgia Athens GA USA Math/CS Department University of Cagliari Italy

Recently, Linked Open Data (LOD) has experienced an exponential growth via publishing huge volume of datasets on the Web. This vast amount of information needs to be searched, queried, and interlinked easier than before. It is recommended that potential data publishers provide recapitulative information about their datasets published on the Web. This information, which functions as metadata, will facilitate those datasets to be discovered easily. As it is not always the case, we are faced with a large number of datasets without a proper profile, leading to a high demand for different data profiling techniques. In this paper, we focus on RDF dataset profiling utilizing unsupervised machine learning techniques, namely knowledge based topic modeling. We also investigate the use of Wikipedia categories to represent the topics identified in an RDF dataset. In the proposed model, we extract a number of representative topics for an RDF dataset and annotate them with Wikipedia categories. The union of the assigned categories serves as a profile of the dataset, in a sense that it provides an overall characterization of the content of the dataset.

关键词： Resource description framework Encyclopedias Electronic publishing Coherence Computational modeling

User review-based change file localization for mobile applications

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arXiv 2019年

作者： Zhou, Yu Su, Yanqi Chen, Taolue Huang, Zhiqiu Gall, Harald Panichella, Sebastiano College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China The State Key Laboratory for Novel Software Technology Nanjing University Nanjing China Department of Computer Science and Information Systems Birkbeck University of London United Kingdom Department of Informatics University of Zurich Switzerland Zurich University of Applied Science Switzerland

In the current mobile app development, novel and emerging DevOps practices (e.g., Continuous Delivery, Integration, and user feedback analysis) and tools are becoming more widespread. For instance, the integration of user feedback (provided in the form of user reviews) in the software release cycle represents a valuable asset for the maintenance and evolution of mobile apps. To fully make use of these assets, it is highly desirable for developers to establish semantic links between the user reviews and the software artefacts to be changed (e.g., source code and documentation), and thus to localize the potential files to change for addressing the user feedback. In this paper, we propose RISING (Review Integration via claSsification, clusterIng, and linkiNG), an automated approach to support the continuous integration of user feedback via classification, clustering, and linking of user reviews. RISING leverages domain-specific constraint information and semi-supervised learning to group user reviews into multiple fine-grained clusters concerning similar users’ requests. Then, by combining the textual information from both commit messages and source code, it automatically localizes potential change files to accommodate the users’ requests. Our empirical studies demonstrate that the proposed approach outperforms the state-of-the-art baseline work in terms of clustering and localization accuracy, and thus produces more reliable results. Copyright © 2019, The Authors. All rights reserved.

关键词： Integration

Toward Complete Transformation of Sodium Polysulfides by Regulating the Second-Shell Coordinating Environment of Atomically Dispersed Fe

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Angewandte Chemie 2023年第26期135卷

作者： Ruilin Bai Qiaosong Lin Xinyu Li Fangxin Ling Huijuan Wang Sha Tan Lingxiang Hu Mingze Ma Prof. Xiaojun Wu Yu Shao Xianhong Rui Prof. Enyuan Hu Dr. Yu Yao Prof. Yan Yu Hefei National Research Center for Physical Sciences at the Microscale Department of Materials Science and Engineering CAS Key Laboratory of Materials for Energy Conversion University of Science and Technology of China Hefei Anhui 230026 China Contribution: Conceptualization (lead) Writing - original draft (lead) State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China University of Chinese Academy of Sciences Beijing 100049 China Contribution: Data curation (lead) Contribution: Formal analysis (equal) Contribution: Investigation (lead) Experimental Center of Engineering and Material Science University of Science and Technology of China Hefei 230026 China Contribution: Methodology (equal) Chemistry Division Brookhaven National Laboratory Upton NY USA Contribution: Resources (equal) Department of Electrical Engineering and Computer Science Institut Polytechnique de Paris 91120 Palaiseau Île-de-France France Contribution: Software (equal) Contribution: Data curation (equal) Jiujiang DeFu Technology Co. Ltd. Jiujiang Jiangxi 332000 (P. R. China School of Materials and Energy Guangdong University of Technology Guangzhou 510006 China Contribution: Validation (lead) Contribution: Methodology (lead) Contribution: Writing - review & editing (lead) National Synchrotron Radiation Laboratory Hefei Anhui 230026 China Contribution: Project administration (lead) Writing - review & editing (lead)

Room temperature sodium-sulfur (RT Na-S) batteries are highly competitive as potential energy storage devices. Nevertheless, their actually achieved reversible capacities are far below the theoretical value due to incomplete transformation of polysulfides. Herein, atomically dispersed Fe-N/S active center by regulating the second-shell coordinating environment of Fe single atom is proposed. The Fe−N 4 S 2 coordination structure with enhanced local electronic concentration around the Fermi level is revealed via synchrotron radiation X-ray absorption spectroscopy (XAS) and theoretical calculations, which can not only significantly promote the transformation kinetics of polysulfides, but induce uniform Na deposition for dendrite-free Na anode. As a result, the obtained S cathode delivers a high initial reversible capacity of 1590 mAh g −1 , nearly the theoretical value. This work opens up a new avenue to facilitate the complete transformation of polysulfides for RT Na-S batteries.

关键词： Catalysis Coordinating Environment Fe Single Atom RT Na-S Batteries Transformation Kinetics