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Anti-Byzantine Attacks Enabled Vehicle Selection for Asynchronous Federated Learning in Vehicular Edge Computing

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China Communications 2024年第8期21卷 1-17页

作者： Zhang Cui Xu Xiao Wu Qiong Fan Pingyi Fan Qiang Zhu Huiling Wang Jiangzhou School of Internet of Things Engineering Wuxi Institute of TechnologyWuxi 214121China School of Internet of Things Engineering Jiangnan UniversityWuxi 214122China Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua UniversityBeijing 100084China Qualcomm San Jose CA 95110USA School of Engineering University of KentCT27NT CanterburyU.K

In vehicle edge computing(VEC),asynchronous federated learning(AFL)is used,where the edge receives a local model and updates the global model,effectively reducing the global aggregation *** to different amounts of local data,computing capabilities and locations of the vehicles,renewing the global model with same weight is *** above factors will affect the local calculation time and upload time of the local model,and the vehicle may also be affected by Byzantine attacks,leading to the deterioration of the vehicle ***,based on deep reinforcement learning(DRL),we can consider these factors comprehensively to eliminate vehicles with poor performance as much as possible and exclude vehicles that have suffered Byzantine attacks before *** the same time,when aggregating AFL,we can focus on those vehicles with better performance to improve the accuracy and safety of the *** this paper,we proposed a vehicle selection scheme based on DRL in *** this scheme,vehicle’s mobility,channel conditions with temporal variations,computational resources with temporal variations,different data amount,transmission channel status of vehicles as well as Byzantine attacks were taken into *** results show that the proposed scheme effectively improves the safety and accuracy of the global model.

关键词： asynchronous federated learning byzantine attacks vehicle selection vehicular edge computing

The Paradigm of Power Bounded High-Performance Computing

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Journal of Computer Science & Technology 2023年第1期38卷 87-102页

作者： Rong Ge Xizhou Feng Pengfei Zou Tyler Allen School of Computing Clemson UniversityClemsonSC 29634U.S.A. Meta Platform Inc.Menlo ParkCA 94025U.S.A. Amazon Inc.SeattleWA 98170U.S.A. university of North Carolina at Charlotte NC 27599U.S.A.

Modern computer systems are increasingly bounded by the available or permissible power at multiple layers from individual components to data *** cope with this reality,it is necessary to understand how power bounds im-pact performance,especially for systems built from high-end nodes,each consisting of multiple power hungry *** placing an inappropriate power bound on a node or a component can lead to severe performance loss,coordinat-ing power allocation among nodes and components is mandatory to achieve desired performance given a total power *** this article,we describe the paradigm of power bounded high-performance computing,which considers coordinated power bound assignment to be a key factor in computer system performance analysis and *** apply this paradigm to the problem of power coordination across multiple layers for both CPu and GPu *** several case studies,we demonstrate how the principles of balanced power coordination can be applied and adapted to the inter-play of workloads,hardware technology,and the available total power for performance improvement.

关键词： power bounded computing cross-component power coordination hierarchical power allocation

Power equipment vibration visualization using intelligent sensing method based on event-sensing principle

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Global Energy Interconnection 2024年第2期7卷 228-240页

作者： Mingzhe Zhao Xiaojun Shen Lei Su Zihang Dong Tongji university No.1239 Siping RoadYangpu DistrictShanghai 200092P.R.China State Grid Shanghai Municipal Electric Power Company Electric Power Science Research Institute Shanghai 200437P.R.China Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72AZU.K.

Vibration measurements can be used to evaluate the operation status of power equipment and are widely applied in equipment quality inspection and fault ***-sensing technology can sense the change in surface light intensity caused by object vibration and provide a visual description of vibration *** on the analysis of the principle underlying the transformation of vibration behavior into event flow data by an event sensor,this paper proposes an algorithm to reconstruct event flow data into a relationship correlating vibration displacement and time to extract the amplitude-frequency characteristics of the vibration signal.A vibration measurement test platform is constructed,and feasibility and effectiveness tests are performed for the vibration motor and other power *** results show that event-sensing technology can effectively perceive the surface vibration behavior of power and provide a wide dynamic ***,the vibration measurement and visualization algorithm for power equipment constructed using this technology offers high measurement accuracy and *** results of this study provide a new noncontact and visual method for locating vibrations and performing amplitude-frequency analysis on power equipment.

关键词： Power equipment Event sensing Non contact measurement Graphic display Feasibility

Micro-scale Abrasion and Medium Load Multiple Scratch Tests of PVD Coatings

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材料热处理学报 2004年第5B期25卷 1199-1202页

作者： S. Poulat D.G Teer Teer Coatings Ltd Droitwich Worcestershire.U.K.Teer Coatings Ltd Droitwich Worcestershire.U.K.

Micro-scale abrasion testing is widely used to determine the abrasion resistance of thin film coatings; it is a simple technique that can easily be used as part of a quality control procedure, but it has got the disadvantage of not allowing an easy study of the wear mechanisms involved: it is difficult to estimate the load applied on each abrasive particles in the contact between the loaded ball and the specimen. The possibility of using progressive loading scratch testing, a method widely used to assess the adhesion of thin film coatings, to model the abrasive wear of coatings has been studied in the past; the use of multiple scratch tests to study the wear mechanisms corresponding to a single abrasion scratch event has also been studied in the case of bulk materials (ceramics and hard metals). Two coatings, deposited by Closed Field unbalanced Magnetron Sputter Ion Plating (CFuBMSIP) on ASP23 powder metallurgy steel substrate are chosen to be representative of the use of protective coatings in industry: titanium nitride, which is widely used to prevent tool wear, and TCL Graphit-iC?, which is widely used as a wear resistant solid lubricant coating. The two coatings are first characterised by using a standard quality control procedure: their thickness is determined by the cap grinding method, their adhesion by progressive loading scratch. Then micro-scale abrasion tests performed with a slurry at a concentration which promotes grooving wear, and medium load multiple scratch tests performed with diamond indenters are completed; the results of these tests are analysed and compared to determine if there is any correlation between the two sets of results; the multiple scratch tests wear tracks are also observed to determine the wear mechanisms involved.

关键词：微量磨损乱痕硬度试验 PVD 薄膜涂层

The Friction and Wear Properties of CrN, Graphit-iC and Dymon-iC Coatings in Air and under Oil-lubrication.

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材料热处理学报 2004年第5B期25卷 858-861页

作者： J. Stallard D.G Teer Teer Coatings Ltd Droitwich WorcestershireU.KTeer Coatings Ltd Droitwich WorcestershireU.K.

Hard ceramic coatings such as TiN and CrN are very successful and are widely used in improving the performance of cutting and forming tools, but they are less successful in providing protection for general machine components, such as gears and engine parts. The development of low-friction wear resistant coatings that can run dry or in a minimum amount of oil is becoming increasingly important to this industry. Two recently developed carbon-based coatings Graphit-iC? and Dymon-iC, which are shown to exhibit very high sliding wear resistance and low friction in dry conditions, are compared to a CrN coating under oil lubricated conditions. Long term pin-on-disc tests using a chrome steel counterface ball were carried out on coated HSS test samples. All the coatings performed well at very high applied contact pressures, exceeding 1.5 GPa, but the Graphit-iC? and Dymon-iC coatings also exhibited the desirable characteristic of protecting the counterface material. Reasons for this behaviour are discussed.

关键词： DLC 润滑油摩擦性能磨损性能涂层

From Sequential Pattern Mining to Structured Pattern Mining： A Pattern-Growth Approach

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Journal of Computer Science & Technology 2004年第3期19卷 257-279页

作者： Jia-WeiHan JianPei Xi-FengYan universituofIllinoisaturbana-Champaign UrbanaIL61801U.S.A. StateuniversityofNewYorkatBuffalo BuffaloNY14260-2000U.S.A.

Sequential pattern mining is an important data mining problem with broadapplications. However, it is also a challenging problem since the mining may have to generate orexamine a combinatorially explosive number of intermediate subsequences. Recent studies havedeveloped two major classes of sequential pattern mining methods: (1) a candidategeneration-and-test approach, represented by (ⅰ) GSP, a horizontal format-based sequential patternmining method, and (ⅱ) SPADE, a vertical format-based method; and (2) a pattern-growth method,represented by PrefixSpan and its further extensions, such as gSpan for mining structured *** this study, we perform a systematic introduction and presentation of the pattern-growthmethodology and study its principles and extensions. We first introduce two interestingpattern-growth algorithms, FreeSpan and PrefixSpan, for efficient sequential pattern mining. Then weintroduce gSpan for mining structured patterns using the same methodology. Their relativeperformance in large databases is presented and analyzed. Several extensions of these methods arealso discussed in the paper, including mining multi-level, multi-dimensional patterns and miningconstraint-based patterns.

关键词： data mining sequential pattern mining structured pattern mining scalability performance analysis

Penalty Formulations and Trap-Avoidance Strategies for Solving Hard Satisfiability Problems

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Journal of Computer Science & Technology 2005年第1期20卷 3-17页

作者： BenjaminW.Wah ZheWu DepartmentofElectricalandComputerEngineering UniversityofIllinoisUrbanaIL61801U.S.A. OracleCorporation OneOracleDriveNashuaNH03062U.S.A.

In this paper we study the solution of SAT problems formulated as discretedecision and discrete constrained optimization problems. Constrained formulations are better thantraditional unconstrained formulations because violated constraints may provide additional forces tolead a search towards a satisfiable assignment. We summarize the theory of extended saddle pointsin penalty formulations for solving discrete constrained optimization problems and the associateddiscrete penalty method (DPM). We then examine various formulations of the objective function,choices of neighborhood in DPM, strategies for updating penalties, and heuristics for avoidingtraps. Experimental evaluations on hard benchmark instances pinpoint that traps contributesignificantly to the inefficiency of DPM and force a trajectory to repeatedly visit the same set ofor nearby points in the original variable space. To address this issue, we propose and study twotrap-avoidance strategies. The first strategy adds extra penalties on unsatisfied clauses inside atrap, leading to very large penalties for unsatisfied clauses that are trapped more often and makingthese clauses more likely to be satisfied in the future. The second strategy stores information onpoints visited before, whether inside traps or not, and avoids visiting points that are close topoints visited before. It can be implemented by modifying the penalty function in such a way that,if a trajectory gets close to points visited before, an extra penalty will take effect and force thetrajectory to a new region. It specializes to the first strategy because traps are special cases ofpoints visited before. Finally, we show experimental results on evaluating benchmarks in the DIMACSand SATLIB archives and compare our results with existing results on GSAT, WalkSAT, LSDL, andGrasp. The results demonstrate that DPM with trap avoidance is robust as well as effective forsolving hard SAT problems.

关键词： knowledge representation and reasoning techniques of algorithms constraintsatisfaction boolean satisfiability penalty formulation saddle point search

在复二维仿射锥上的完备余齐性一Kahler度量

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Chinese Quarterly Journal of Mathematics 2024年第2期39卷 200-220页

作者：关庄丹梁梦翔 School of Mathematics and Statistics Henan UniversityKaifeng 475004China Department of Mathematics University of California at RiversideCA 92521U.S.A.

In this paper,we revisit the Kahler structures on the affine quadrics M1={z_(1)^(2)+z_(2)^(2)+z_(3)^(2)=1}in the paper by Bo Yang and Fang-Yang *** found that the Kahler structures on the complex surface are more complicated than what they have *** shall also give some detail calculations and found that our results fit quite well with earlier papers of the first author,one of them with ***.

关键词： Affine quadrics Complex structure Kahler metrics Cohomogeneity one action

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u-blox发布整合3D传感器的终极室内/室外定位模块NEO-M8L

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微型机与应用 2014年第22期33卷 36-36页

作者： u-blox u-blox

首款一体化（ all-in-one ） GNSS模块为道路车辆系统带来全新的性能等级为汽车、工业和消费市场提供无线和定位模块与芯片的全球领导业者瑞士公司u-blox宣布推出整合了运动、方向和高度传感器的NEO-M8L汽车惯性导航（Automotive Dead R... 详细信息

首款一体化（ all-in-one ） GNSS模块为道路车辆系统带来全新的性能等级为汽车、工业和消费市场提供无线和定位模块与芯片的全球领导业者瑞士公司u-blox宣布推出整合了运动、方向和高度传感器的NEO-M8L汽车惯性导航（Automotive Dead Reckoning，ADR）模块。该模块将陀螺仪和加速度传感器与u-blox领先的GNSS平台-u-blox M8集成在一起，使其成为市场上性能最佳的室内／室外定位解决方案，是所有道路车辆和高精度导航应用的理想选择。

关键词：定位模块高度传感器室外室内整合 all-in-one 3D 加速度传感器