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An Adaptive Task Creation Pruning Strategy for Optimizing Irregular Applications

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Chinese Journal of Electronics 2015年第3期24卷 535-541页

作者： CAO Qian LI Huiyong ZUO min DENG yun YU Yuan School of Computer and Information Engineering Beijing Technology and Business University School of Electronics Engineering and Computer Science Peking University College of Information Science and Engineering Guilin University of Technology

The Open MP task directive makes it possible to efficiently parallelize irregular applications, with task granularity as one of the most critical issues. To implement Open MP specification on multi-core architecture,a model is presented specializing in the execution of irregular applications. The model captures computation and communication within a node with host cores and accelerator cores. Based on this model, we propose an adaptive task creation pruning strategy including two stages to adjust dynamically task granularity. The first stage is task creation in breadth-first manner until getting to a threshold, which utilizes potential parallelism of multi-core processor. The second stage is starvation-triggered task regeneration once some worker thread becomes starved, which ensures work-stealing and thus achieves load balance. The evaluation is conducted with a series of typical irregular benchmarks, and the results indicate that our approach offers more effective performance in parallel execution of irregular benchmarks.

关键词： Task granularity Adaptive Irregular applications Multi-core

New Multi-Channel VSMFxLMS Algorithm for Vibration Reduction of Gear Systems

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Chinese Journal of Mechanical Engineering 2024年第5期37卷 233-247页

作者： Zhibo Geng min Chen Yingjian Wang yun Kong Ke Xiao School of Aeronautics and Astronautics University of Electronic Science and technology of ChinaChengdu 611731China Yangtze Delta Region Institute University of Electronic Science and Technology of ChinaHuzhou 313000China School of Mechanical Engineering Bejing Institute of TechnologyBeijing 100081China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China

At present,the active control of gear vibration mostly relies on existing *** order to achieve effective vibration reduction of the gear system,particularly during the vibration process,this paper proposes a multi-channel VSMFxLMS algorithm based on the FxLMS *** novel approach takes into account the time-varying nature of the vibration signal during gear *** filter power coefficients are updated in a skip-tongue variable-step manner using momentum ***,the paper establishes the dynamics model of the gear system and analyzes the nonlinear dynamic characteristics of the *** then examines the vibration damping effect of the FxLMS algorithm and analyzes its performance under different gear system motion states,considering different step lengths and momentum ***,the proposed VSMFxLMS algorithm is compared with the FxLMS algorithm,highlighting the superiority of the ***,this research highlights the potential of a multi-channel VSMFxLMS algorithm in reducing vibrations in gear *** study optimizes the performance of gear systems while using advanced control strategies.

关键词： Vibration reduction Gear system FxLMS algorithm Multi-channel VSMFxLMS algorithm

Fabrication and characterization of nanoporous Ag-Pt alloy

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Rare Metals 2021年第5期40卷 1203-1207页

作者： Tao Yin Fan-yun Meng min Zhang Ying-Wei Yan Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Engineering Research Centre of Natural Medicine Ministry of EducationFaculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Mechanical Electronic and Control EngineeringMaterials Science and Engineering Research CenterBeijing Jiaotong UniversityBeijing 100044China

Nanoporous Ag-Pt bi-metallic alloy was fabricated by free dealloying of amorphous Ag-based precursor with the nominal composition of *** noble Ag and Pt were left after the less noble Cu and Si dissolved in a certain acid ***-continuous nanoporous microstructure was formed with asymmetric ligaments and pores with typically 30-200 nm in *** trace addition of Pt has refined the grains of the ligaments to the average size of less than 20 nm in the substrate and induced the formation of rods with *** morphologies of the rods were observed by scanning electron microscopy(SEM)and transmission electron microscopy(TEM)both in the form of clusters and as scattered individuals with characteristic length of several micrometers and diameter of tens of *** grains sizes in the rods were finer than those in the *** good mechanical integrity might be due to the combination of continuous ligaments and clusters of rods.

关键词： Nanoporous Ag-Pt alloy Amorphous precursor Dealloying Nanograins

Rhus laccase catalysis and product characterization of 1,2-dimethoxyphenol in organic solutions

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Chinese Chemical Letters 2008年第3期19卷 333-336页

作者： yun Yang Wan Yu min Du Tetsuo Miyakoshi State Key Laboratory of Petroleum Resources and Prospecting Faculty of Natural Resources and Information TechnologyChina University of Petroleum Beifing 102249 China Department of Industrial Chemistry Meifi University Higashi-mita Tama-ku Kawasaki 214 Japan School of Resource and Environment Science Wuhan University Wuhan 430079 China

Dimethoxyphenol was a widely used substrate in determination of laccases activity. It was surprised, however, that the products of it had not been completely determined until now. Studies were thus conducted on Rhus laccase （RL） and immobilized Rhus laccase （IRL）-catalyzed oxidation of 2,6-dimethoxyphenol （DMP） in water-organic solvent systems. Only one product, 3,3′,5,5′- tetramethoxy-1 ,1′-biphenyl-4,4′-diol （TMBP）, was produced by RL catalysis, and it was thoroughly characterized by FT-IR, NMR and GC-MS, etc.

关键词： Rhus laccase Laccase-catalyzed oxidation Organic solvents 2,6-Dimethoxyphenol

Facile and Stereoselective Synthesis of N-Substituted Benzotriazole with Baylis-Hillman Adducts

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Chinese Chemical Letters 2006年第7期17卷 877-879页

作者： Jian LI yun Kui LIU Yong min ZHANG Department of Chemistry Shanghai University Shanghai 200436 Department of Chemistry Zhejiang University Xixi Campus Hangzhou 310028 State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Catalytic Hydrogenation Research Center Zhejiang University of Technology Hangzhou 310014 State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032

A convenient method has been developed toward the stereoselective synthesis of N-substituted benzotriazole derivatives under mild conditions. The good stereolectivity, high yields and the simple procedure make the pre... 详细信息

关键词： Benzotriazole N-substituted Baylis-Hillman adduct.

Electrocrystallizations of copper on glassy carbon in CuCl_2 silica sol and aqueous solutions

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Chinese Chemical Letters 2012年第2期23卷 249-252页

作者： Yan Yan Feng min Gu yun Gui Du State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam State Key Laboratory of Coal Mine Disaster Dynamics and ControlChongqing UniversityChongqing 400044China

Electrocrystallizations of copper from both CuCl_2 silica sol and aqueous solutions were studied by the chronoamperometry *** was found that current density contributions of the double-layer charging（iDL） in current-time transients（CTTs） from both of the solutions were *** adsorption-nucleation based model was proposed to analyze quantitatively the CTTs,by which copper electrocrystallization mechanism was characterized as progressive nucleation with 3D growth（3DP） under diffusion *** diffusion coefficient of copper ions and the AN_∞products in aqueous solutions were larger than that in silica sols, which indicated that copper nucleation was inhibited in sol *** large iDL may be resulted from the adsorption of chloride ions on the electrode surface.

关键词： CuCl_2 Silica sol Aqueous Current-time transients(CTTs) Copper Electrocrystallization

Implementation of a Subjective Visual Vertical and Horizontal Testing System Using Virtual Reality

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Computers, Materials & Continua 2021年第6期67卷 3669-3679页

作者： Sungjin Lee min Hong Hongly Va Ji-yun Park Department of Software Convergence Soonchunhyang UniversityAsan31538Korea Department of Computer Software Engineering Soonchunhyang UniversityAsan31538Korea Department of Neurology University of Ulsan college of MedicineUlsan University HospitalUlsan44033Korea

Subjective visual vertical(SVV)and subjective visual horizontal(SVH)tests can be used to evaluate the perception of verticality and horizontality,respectively,and can aid the diagnosis of otolith dysfunction in clinical *** this study,SVV and SVH screen version tests are implemented using virtual reality(VR)equipment;the proposed test method promotes a more immersive feeling for the subject while using a simple equipment configuration and possessing excellent *** verify the performance of the proposed VR-based SVV and SVH tests,a reliable comparison was made between the traditional screen-based SVV and SVH tests and the proposed method,based on 30 healthy *** average results of our experimental tests on the VR-based binocular SVV and SVH equipment were−0.15◦±1.74 and 0.60◦±1.18,*** proposed VR-based method satisfies the normal tolerance for horizontal or vertical lines,i.e.,a±3◦error,as defined in previous studies,and it can be used to replace existing test methods.

关键词： Subjective visual vertical subjective visual horizontal virtual reality unity3D FOVE HMD vestibular function tests diagnostic equipment

Explicit Piecewise Smooth Solutions of Landau-Lifshitz Equation with Discontinuous External Field

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 61-74页

作者： Gan-shan Yang yun-zhang Zhang Li-min Liu Institute of Mathematics Science Yunnan Normal University Kunming 650092 China Department of Mathematics Yunnan National University Kunming 650031 China Faculty of Science Xi'an Jiaotong University Xi'an 710049 China College of Mathematics and Physics Chongqing University Chongqiong 400030 China

In this paper, we shall construct some explicit piecewise smooth （global continuous） solutions as well as blow up solutions to the multidimensional Landau-Lifshitz equation, subject to the external magnetic fields being both discontinuous and unbounded. When the external magnetic field is continuous, some explicit exact smooth solutions and blow up solution are also constructed. We also establish some necessary and sufficient conditions to ensure that the solution of multidimensional Landau-Lifshitz equation with external magnetic field converges to the solution of equation without external magnetic field when the external magnetic field tends to zero.

关键词： Multidimensional Landau-Lifshitz equation discontinuous external field piecewise smoothsolution

Complementarity Properties of the Lyapunov Transformation over Symmetric Cones

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Acta Mathematica Sinica,English Series 2012年第7期28卷 1431-1442页

作者： Yuan min LI Xing Tao WANG De yun WEI Department of Mathematics Harbin Institute of Technology National Key Laboratory of Tunable Laser Technology Harbin Institute of Technology

The well-known Lyapunov＇s theorem in matrix theory/continuous dynamical systems as- serts that a square matrix A is positive stable if and only if there exists a positive definite matrix X such that AX＋XA^＊ is positive definite. In this paper, we extend this theorem to the setting of any Euclidean Jordan algebra V. Given any element a E V, we consider the corresponding Lyapunov transformation La and show that the P and S-properties are both equivalent to a being positive. Then we characterize the R0-property for La and show that La has the R0-property if and only if a is invertible. Finally, we provide La with some characterizations of the E0-property and the nondegeneracy property.

关键词： Euclidean Jordan algebra Lyapunov transformation symmetric cone complementarity problem