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IEEE International Conference on high performance computing and Communications (HPCC)

作者： Hongliang Li Ting Sun Xiang Li Haixiao Xu College of Computer Science and Technology Jilin University Changchun China Key Laboratory of Symbolic Computation and Knowledge Engineering of the Ministry of Education Changchun China High Performance Computing Center of Jilin University Changchun China

ISBN: (纸本)9781728176505

Distributed deep learning frameworks train large deep leaning workload with multiple training jobs on shared distributed GPU servers. There are new challenges when scheduling resources for these systems. Modern deep learning training jobs tend to consume large amount of GPU memory. A training job has an iterative nature that causes the memory usage fluctuate overtime. Jobs sharing a host may suffer from significant performance degradation caused by memory overload in runtime. Moreover, even without memory overloads, deep learning training jobs still experience different levels of performance interference when sharing a GPU device. This paper studies these two issues. We introduced an opportunistic memory sharing model to allocate resources for training jobs with time-varying memory requirements. Based on this model, we introduced an opportunistic Job Placement Problem (OJPP) for shared GPU clusters that seeks job placement configurations using minimum number of GPU devices and guarantees user-defined performance requirements. We proposed a greedy algorithm and a heuristic algorithm with computational complexities of $O(n\log n)$ and $O(n^performance\log n)$, respectively, to solve the problem. Extensive experiments are conducted using a GPU cluster to verify the correctness, effectiveness, and the scalability of our approaches. The proposed approach achieved over 80% percent of the standalone performance, in term of average job completion time, with less than 30% extra resources consumption.

关键词： Training Deep learning performance evaluation Greedy algorithms high performance computing Heuristic algorithms Computational modeling

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Mechanism of friction-induced chemical reaction high-efficient polishing single crystal 4H-SiC wafer using pure iron

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Tribology International 2024年 193卷

作者： Wu, Min Huang, Hui Wu, Yueqin Xu, Zhiteng Li, Tukun Macleod, Iain Wu, Xiaolei National and Local Joint Engineering Research Center for Intelligent Manufacturing Technology of Brittle Material Products Huaqiao University Xiamen 361021 China Institute of Manufacturing Engineering Huaqiao University Xiamen 361021 China State Key Laboratory of High-Performance Tools Zhengzhou 450001 China EPSRC Future Advanced Metrology Hub Centre for Precision Technologies School of Computing and Engineering University of Huddersfield Huddersfield HD1 3DH United Kingdom IMA Ltd 29 Clay Lane Cheshire WA15 8PJ United Kingdom Zhengzhou Research Institute for Abrasives & Grinding Co. Ltd Zhengzhou 450001 China

This paper proposes a novel method for friction-induced chemical reaction machining of single-crystal 4H-SiC wafers using pure iron. Material Removal Rate (MRR) and surface quality of single-crystal 4H-SiC were studied, and the results demonstrate that both high surface quality and high MRR (Ra: 2.2 nm, MRR: 375 nm/min) were obtained. The mechanism of material removal during friction was investigated by examining the critical roles of friction speed. Solid-state chemical reactions between metal and SiC surfaces can be induced by friction, and the subsequent removal of reactants, resulting in a near-damage-free machined surface. A removal mechanism model of friction was established, which reveals that both the rates of solid-state reaction and reactant removal significantly impact the final removal rate of friction. © 2024 Elsevier Ltd

关键词： Friction-induced chemical reaction Pure iron Removal mechanism SiC

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A riemannian inexact newton dogleg method for constructing a symmetric nonnegative matrix with prescribed spectrum

arXiv

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arXiv 2021年

作者： Zhao, Zhi Yao, Teng-Teng Bai, Zheng-Jian Jin, Xiao-Qing Department of Mathematics School of Sciences Hangzhou Dianzi University Hangzhou310018 China Department of Mathematics School of Sciences Zhejiang University of Science and Technology Hangzhou310023 China School of Mathematical Sciences Fujian Provincial Key Laboratory on Mathematical Modeling & High Performance Scientific Computing Xiamen University Xiamen361005 China Department of Mathematics University of Macau Macao China

This paper is concerned with the inverse problem of constructing a symmetric nonnegative matrix from realizable spectrum. We reformulate the inverse problem as an underdetermined nonlinear matrix equation over a Riemannian product manifold. To solve it, we develop a Riemannian underdetermined inexact Newton dogleg method for solving a general underdetermined nonlinear equation defined between Riemannian manifolds and Euclidean spaces. The global and quadratic convergence of the proposed method is established under some mild assumptions. Then we solve the inverse problem by applying the proposed method to its equivalent nonlinear matrix equation and a preconditioner for the perturbed normal Riemannian Newton equation is also constructed. Numerical tests show the efficiency of the proposed method for solving the inverse *** Codes 15A18, 65F08, 65F18, 65F15 Copyright © 2021, The Authors. All rights reserved.

关键词： Matrix algebra

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high order semi-implicit WENO schemes for all mach full euler system of gas dynamics

arXiv

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arXiv 2021年

作者： Boscarino, Sebastiano Qiu, Jing-Mei Russo, Giovanni Xiong, Tao Department of Mathematics and Computer Science University of Catania Catania95127 Italy Department of Mathematics University of Delaware NewarkDE19716 United States School of Mathematical Sciences Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen University Fujian Xiamen361005 China

In this paper, we propose a new high order semi-implicit scheme for the all Mach full Euler equations of gas dynamics. Material waves are treated explicitly, while acoustic waves are treated implicitly, thus avoiding severe CFL restrictions for low Mach flows. high order accuracy in time is obtained by semi-implicit temporal integrator based on the IMEX Runge-Kutta (IMEX-RK) framework. high order in space is achieved by finite difference WENO schemes with characteristic-wise reconstructions adapted to the semi-implicit IMEX-RK time discretization. Type A IMEX schemes are constructed to handle not well-prepared initial conditions. Besides, these schemes are proven to be asymptotic preserving and asymptotically accurate as the Mach number vanishes for well-prepared initial conditions. Divergence-free property of the time-discrete schemes is proved. The proposed scheme can also well capture discontinuous solutions in the compressible regime, especially for two dimensional Riemann problems. Numerical tests in one and two space dimensions will illustrate the effectiveness of the proposed schemes. © 2021, CC BY.

关键词： Mach number

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Calculation of heavy meson light-cone distribution amplitudes from lattice QCD

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Physical Review D 2025年第3期111卷 034503-034503页

作者： Xue-Ying Han Jun Hua Xiangdong Ji Cai-Dian Lü Andreas Schäfer Yushan Su Wei Wang Ji Xu Yibo Yang Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Atomic and Subatomic Structure and Quantum Control (MOE) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Institute of Quantum Matter South China Normal University Guangzhou 510006 China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear Science Southern Nuclear Science Computing Center South China Normal University Guangzhou 510006 China Department of Physics University of Maryland College Park Maryland 20742 USA Institut für Theoretische Physik University Regensburg D-93040 Regensburg Germany Shanghai Key Laboratory for Particle Physics and Cosmology Key Laboratory for Particle Astrophysics and Cosmology (MOE) School of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 China Southern Center for Nuclear-Science Theory (SCNT) Institute of Modern Physics Chinese Academy of Sciences Huizhou 516000 Guangdong Province China School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China School of Physics and Microelectronics Zhengzhou University Zhengzhou Henan 450001 China CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study UCAS Hangzhou 310024 China International Centre for Theoretical Physics Asia-Pacific Beijing/Hangzhou China

We develop an approach for calculating heavy quark effective theory (HQET) light-cone distribution amplitudes (LCDAs) by employing a sequential effective theory methodology. The theoretical foundation of the framework is established, elucidating how the quasidistribution amplitudes (quasi-DAs) with three scales can be utilized to compute HQET LCDAs. We provide theoretical support for this approach by demonstrating the rationale behind devising a hierarchical ordering for the three involved scales, discussing the factorization at each step, clarifying the underlying reason for obtaining HQET LCDAs in the final phase, and addressing potential theoretical challenges. The lattice QCD simulation aspect is explored in detail, and the computations of quasi-DAs are presented. We employ three fitting strategies to handle contributions from excited states and extract the bare matrix elements. For renormalization purposes, we apply hybrid renormalization schemes at short and long distance separations. To mitigate long-distance perturbations, we perform an extrapolation in λ=z·Pz and assess the stability against various parameters. After two-step matching, our results for HQET LCDAs are found in agreement with existing model parametrizations. The potential phenomenological implications of the results are discussed, shedding light on how these findings could impact our understanding of the strong interaction dynamics and physics beyond the standard model. It should be noted, however, that systematic uncertainties have not been accounted for yet.

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Efficient Multiplex Symbolic Execution with Adaptive Search Strategy

Efficient Multiplex Symbolic Execution with Adaptive Search ...

引用

IEEE International Conference on Automated Software Engineering (ASE)

作者： Tianqi Zhang Yufeng Zhang Zhenbang Chen Ziqi Shuai Ji Wang College of Computer National University of Defense Technology Changsha China College of Computer Science and Electronic Engineering Hunan University Changsha China State Key Laboratory of High Performance Computing National University of Defense Technology Changsha China

ISBN: (数字)9781450367684

ISBN: (纸本)9781728172811

Symbolic execution is still facing the scalability problem caused by path explosion and constraint solving overhead. The recently proposed MuSE framework supports exploring multiple paths by generating partial solutions in one time of solving. In this work, we improve MuSE from two aspects. Firstly, we use a light-weight check to reduce redundant partial solutions for avoiding the redundant executions having the same results. Secondly, we introduce online learning to devise an adaptive search strategy for the target programs. The preliminary experimental results indicate the promising of the proposed methods.

关键词： Multiplexing Scalability Search problems Explosions Software engineering

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The end-to-end Calibration of LHAASO-WFCTA based on Nitrogen Laser System 38

The end-to-end Calibration of LHAASO-WFCTA based on Nitrogen...

引用

38th International Cosmic Ray Conference, ICRC 2023

作者： Sun, Qinning Min, Zhen Liu, Hu Chen, Long Wang, Yang Zhu, Fengrong Zhang, Shoushan Cao, Zhen Aharonian, F. An, Q. Axikegu Bai, L.X. Bai, Y.X. Bai, L.X. Bai, Y.X. Bao, Y.W. Bastieri, D. Bi, X.J. Bi, Y.J. Cai, H. Cai, J.T. Cao, Zhe Chang, J. Chang, J.F. Chen, B.M. Chen, E.S. Chen, J. Chen, Liang Chen, Liang Chen, Long Chen, M.J. Chen, M.L. Chen, Q.H. Chen, S.H. Chen, S.Z. Chen, T.L. Chen, X.L. Chen, Y. Cheng, N. Cheng, Y.D. Cui, S.W. Cui, X.H. Cui, Y.D. D’Ettorre Piazzoli, B. Dai, B.Z. Dai, H.L. Dai, Z.G. Danzengluobu della Volpe, D. Dong, X.J. Duan, K.K. Fan, J.H. Fan, Y.Z. Fan, Z.X. Fang, J. Fang, K. Feng, C.F. Feng, L. Feng, S.H. Feng, Y.L. Gao, B. Gao, C.D. Gao, L.Q. Gao, Q. Gao, W. Ge, M.M. Geng, L.S. Gong, G.H. Gou, Q.B. Gu, M.H. Guo, F.L. Guo, J.G. Guo, X.L. Guo, Y.Q. Guo, Y.Y. Han, Y.A. He, H.H. He, H.N. He, J.C. He, S.L. He, X.B. He, Y. Heller, M. Hor, Y.K. Hou, C. Hu, H.B. Hu, S. Hu, S.C. Hu, X.J. Huang, D.H. Huang, Q.L. Huang, W.H. Huang, X.T. Huang, X.Y. Huang, Z.C. Ji, F. Ji, X.L. Jia, H.Y. Jiang, K. Jiang, Z.J. Jin, C. Ke, T. Kuleshov, D. Levochkin, K. Li, B.B. Li, Cheng Li, Cong Li, F. Li, H.B. Li, H.C. Li, H.Y. Li, J. Li, K. Li, W.L. Li, X.R. Li, Xin Li, Xin Li, Y. Li, Y.Z. Li, Zhe Li, Zhuo Liang, E.W. Liang, Y.F. Lin, S.J. Liu, B. Liu, C. Liu, D. Liu, H. Liu, H.D. Liu, J. Liu, J.L. Liu, J.S. Liu, J.Y. Liu, M.Y. Liu, R.Y. Liu, S.M. Liu, W. Liu, Y. Liu, Y.N. Liu, Z.X. Long, W.J. Lu, R. Lv, H.K. Ma, B.Q. Ma, L.L. Ma, X.H. Mao, J.R. Masood, A. Min, Z. Mitthumsiri, W. Montaruli, T. Nan, Y.C. Pang, B.Y. Pattarakijwanich, P. Pei, Z.Y. Qi, M.Y. Qi, Y.Q. Qiao, B.Q. Qin, J.J. Ruffolo, D. Rulev, V. Sáiz, A. Shao, L. Shchegolev, O. Sheng, X.D. Shi, J.Y. Song, H.C. Stenkin, Yu.V. Stepanov, V. Su, Y. Sun, Q.N. Southwest Jiaotong University School of Physical Science and Technology No. 999 Xi’an Road Chengdu China Institute of High Energy Physics Chinese Academy of Sciences Key Laboratory of Particle Astrophysics & Experimental Physics Division & Computing Center No. 19B Yuquan Road Beijing100049 China Institute of High Energy Physics Chinese Academy of Sciences TIANFU Cosmic Ray Research Center No. 1500 Kezhi Road Chengdu China University of Chinese Academy of Sciences Beijing100049 China TIANFU Cosmic Ray Research Center Sichuan Chengdu China Dublin Institute for Advanced Studies 31 Fitzwilliam Place Dublin 2 Ireland Max-Planck-Institut for Nuclear Physics P.O. Box 103980 Heidelberg69029 Germany State Key Laboratory of Particle Detection and Electronics China University of Science and Technology of China Anhui Hefei230026 China School of Physical Science and Technology School of Information Science and Technology Southwest Jiaotong University Sichuan Chengdu610031 China College of Physics Sichuan University Sichuan Chengdu610065 China School of Astronomy and Space Science Nanjing University Jiangsu Nanjing210023 China Center for Astrophysics Guangzhou University Guangdong Guangzhou510006 China School of Physics and Technology Wuhan University Hubei Wuhan430072 China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory Chinese Academy of Sciences Jiangsu Nanjing210023 China Hebei Normal University Hebei Shijiazhuang050024 China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai200030 China Ministry of Education Tibet Lhasa850000 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China Sun Yat-sen University Guangdong Zhuhai519000 China Dipartimento di Fisica dell’Università di Napoli ‘Federico II" Complesso Universitario di Monte Sant’Angelo via Cinthia Napoli80126 Italy School of Physics and As

The Wide Field-of-view Cherenkov Telescope Array (WFCTA) of Large high Altitude Air Shower Observatory (LHAASO) is designed to perform nearly calorimetric measurements of extensive air showers induced by cosmic rays with energies between 1013 eV - 1018 eV. In order to achieve an end-to-end calibration of WFCTA and investigate properties of the atmospheric aerosol, five laser systems have been operated at LHAASO, including 3 nitrogen and 2 Nd:YAG laser devices. This work presents an overview of the laser signals received by the telescope and the monitoring of geometric information related to nitrogen laser events. Additionally, it introduces the simulation method for the LHAASO-WFCTA laser calibration system. Through prolonged and stable operation, a substantial amount of data has been accumulated, requiring further data analysis for the calibration of the telescope’s absolute gain and measurement of aerosol extinction coefficients. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Cosmology

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Evaluation of model checkers by verifying message passing programs

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中国科学:化学（英文版） 2019年第10期62卷 2-26页

作者： Weijiang HONG Zhenbang CHEN Hengbiao YU Ji WANG College of Computer National University of Defense Technology Changsha 410073 China State Key Laboratory of High Performance Computing National University of Defense TechnologyChangsha 410073 China College of Computer National University of Defense Technology Changsha 410073 China

Benchmarks and evaluation are important for the development of techniques and *** regarding evaluation of model checkers by large-scale benchmarks are *** lack of such studies is mainly because of the language difference of existing model checkers and the requirement of intensive labor in building *** this study,we present a large-scale benchmark for evaluating model checkers whose inputs are concurrent *** benchmark consists of 2318 models that are generated automatically from real-world message passing interface (MPI) *** complexities of the models have been inspected to be well distributed and suitable for evaluating model *** on the benchmark,we have evaluated five state-of-the-art model checkers,i.e.,PAT,FDR,Spin,PRISM,and NuSMV,by verifying the deadlock freedom *** evaluation results demonstrate the ability and performance difference of these model checkers in verifying message passing programs.

关键词： model checker evaluation benchmark MPI symbolic execution

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Mechanism of Friction-Induced Chemical Reaction high-Efficient Polishing Single Crystal 4h-Sic Wafer Using Pure Iron

SSRN

引用

SSRN 2023年

作者： Wu, Min Huang, Hui Wu, Yueqin Xu, Zhiteng Li, Tukun Macleod, Iain Wu, Xiaolei National and Local Joint Engineering Research Center for Intelligent Manufacturing Technology of Brittle Material Products Huaqiao University Xiamen361021 China Institute of Manufacturing Engineering Huaqiao University Xiamen361021 China State Key Laboratory of High-Performance Tools Zhengzhou450001 China EPSRC Future Advanced Metrology Hub Centre for Precision Technologies School of Computing and Engineering University of Huddersfield HuddersfieldHD1 3DH United Kingdom IMA Ltd 29 Clay Lane CheshireWA15 8PJ United Kingdom Zhengzhou Research Institute for Abrasives & Grinding Co. Ltd Zhengzhou450001 China

This paper proposes a novel method for friction-induced chemical reaction machining of single-crystal 4H-SiC wafer using a pure iron. Material Removal Rate (MRR) and surface quality of single-crystal 4H-SiC were studied, and the results demonstrate that both high surface quality and MRR (Ra: 2.2 nm, MRR: 375 nm/min) were obtained. The mechanism of material removal during friction was investigated by examining the critical roles of friction speed. Solid-state chemical reaction between metal and SiC surfaces can be induced by friction, and the subsequent removal of reactants resulting in a near-damage-free machined surface. A removal mechanism model of friction was established, which reveals that both the rates of solid-state reaction and reactant removal significantly impact the final removal rate of friction. © 2023, The Authors. All rights reserved.

关键词： Silicon carbide

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Fourth-Order Conservative Non-Splitting Semi-Lagrangian Hermite Weno Schemes for Kinetic and Fluid Simulations

SSRN

引用

SSRN 2022年

作者： Zheng, Nanyi Cai, Xiaofeng Qiu, Jing-Mei Qiu, Jianxian School of Mathematical Sciences Xiamen University Fujian Xiamen361005 China Research Center for Mathematics Beijing Normal University Zhuhai519087 China BNU-HKBU United International College Zhuhai519087 China Department of Mathematical Sciences University of Delaware NewarkDE19716 United States School of Mathematical Sciences Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen University Fujian Xiamen361005 China

We present fourth-order conservative non-splitting semi-Lagrangian (SL) Hermite essentially non-oscillatory (HWENO) schemes for linear transport equations with applications for nonlinear problems including the Vlasov-Poisson system, the guiding center Vlasov model, and the incompressible Euler equations in the vorticity-stream function formulation. The proposed SL HWENO schemes combine a weak formulation of the characteristic Galerkin method with two newly constructed HWENO reconstruction methods. Fourth-order accuracy is accomplished in both space and time under a non-splitting setting. Mass conservation naturally holds due to the weak formulation of the characteristic Galerkin method and the design of the HWENO reconstructions. We apply a positive-preserving limiter to maintain the positivity of numerical solutions when needed. Although the proposed SL framework allows us to take large time steps for improving computational efficiency, it also brings challenges to the spatial reconstruction technique;we construct two kind of novel HWENO reconstructions to fit the need for the proposed SL framework. Abundant benchmark tests are performed to verify the effectiveness of the proposed SL HWENO schemes. © 2022, The Authors. All rights reserved.

关键词： Computational efficiency

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