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Residual-Based False Data Injection Attacks Against Multi-Sensor Estimation Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第5期10卷 1181-1191页

作者： Haibin Guo Jian Sun zhong-hua Pang the National Key Laboratory of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of TechnologyBeijing 100081China the Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China the Key Laboratory of Fieldbus Technology and Automation of Beijing North China University of TechnologyBeijing 100144China

This paper investigates the security issue of multisensor remote estimation *** optimal stealthy false data injection(FDI)attack scheme based on historical and current residuals,which only tampers with the measurement residuals of partial sensors due to limited attack resources,is proposed to maximally degrade system estimation *** attack stealthiness condition is given,and then the estimation error covariance in compromised state is derived to quantify the system performance under *** optimal attack strategy is obtained by solving several convex optimization problems which maximize the trace of the compromised estimation error covariance subject to the stealthiness ***,due to the constraint of attack resources,the selection principle of the attacked sensor is provided to determine which sensor is attacked so as to hold the most impact on system ***,simulation results are presented to verify the theoretical analysis.

关键词： Cyber-physical systems(CPSs) false data injection(FDI)attacks remote state estimation stealthy attacks

A study on the surface overpressure distribution and formation of a double curvature liner under a two-point initiation

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Defence Technology（防务技术） 2022年第1期18卷 148-157页

作者： Jie Liu Xi Chen zhong-hua Du Nanging Vocational University of Industry Technology Nanjing210023China Nanjing University of Science and Technology Nanjing.210094China

The formation mechanism of an EFP(explosively formed projectile)using a double curvature liner under the overpressure effect generated by a regular oblique reflection was investigated in this *** on the detonation wave propagation theory,the change of the incident angle of the detonation wave collision at different positions and the distribution area of the overpressure on the surface of the liner were *** dimensional numerical simulations of the formation process of the EFP with *** well as the ability to penetrate 45#steel were performed using LS-DYNA software,and the EFP ve locity,the penetration ability,and the forming were assessed via experiments and x_ray *** experimental results coincides with those of the *** indicate that the collision of the detonation wave was controlled to be a regular oblique reflection acting on the liner by setting the di-mensions of the unit charge and maintai ning the pressure at the collision point region at more than 2.4 times the CJ detonation when the incident angle approached the cnitical *** distance from the liner midline to the boundary of the area within which the pressure ratio of the regular oblique reflection pressure to the qJ detonation pressure was greater than 2.5,2,and 15was approximately 0.66 mm,132 mm,and 3.3 mm,*** noted that pressure gradient caused the liner to turn inside out in the middle to form the head of the EFP and close the two tails of the EFP at approximately 120μ*** penetration depth of the EFP into a 45#steel target exceeded 30 mm,and there was radial expansion between the head and tail of the EFP,increasing the penetration resistance of the ***,the structural size of the unit charge and the liner can be further optimized to reduce resist ance to increase the penetration ability of the EFP.

关键词： Unit-shaped charge Double curvature liner Regular oblique reflection Two-point initiation Pene tra tion Numerical simulation

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服务器无感知计算系统性能优化技术研究综述

软件学报 2025年第1期36卷 47-78页

作者：杨光刘杰曲慕子王帅叶丹钟华中国科学院大学中国科学院软件研究所软件工程技术研究开发中心计算机科学国家重点实验室(中国科学院软件研究所)

服务器无感知计算是新兴的云计算模式,它基于“函数即服务(FaaS)”的范式,以函数为部署和调度的基本单位,为用户提供大规模并行和自动伸缩的函数执行服务,且无需用户管理底层资源.对于用户,服务器无感知计算能够帮助他们摆脱集群底层基... 详细信息

服务器无感知计算是新兴的云计算模式,它基于“函数即服务(FaaS)”的范式,以函数为部署和调度的基本单位,为用户提供大规模并行和自动伸缩的函数执行服务,且无需用户管理底层资源.对于用户,服务器无感知计算能够帮助他们摆脱集群底层基础设施管理的负担,专注于业务层的开发和创新;对于服务提供商,服务器无感知计算将应用分解为细粒度的函数,极大地提高了调度效率和资源利用率.显著的优势让服务器无感知计算迅速吸引了业界的注意,然而,服务器无感知计算与传统云计算迥然不同的计算模式以及对任务各方面的严格限制给应用的迁移带来了诸多障碍,各种越来越复杂的任务也对服务器无感知计算的性能提出了越来越高的要求,服务器无感知计算的性能优化成为一个重要的研究课题.从4个方面对服务器无感知计算系统性能优化技术的相关研究工作进行梳理和综述,并介绍现有的系统实现.(1)介绍面向典型任务的优化技术,包括任务适配和针对特定任务的系统优化;(2)综述沙箱环境的优化工作,包括沙箱方案和冷启动优化技术,它们是决定函数运行速度的核心;(3)概括I/O和通信技术的优化,它们是服务器无感知计算应用程序的主要性能瓶颈;(4)简述相关的资源调度技术,包括面向平台和面向用户的调度策略,它们决定着系统的资源利用率和任务的执行效率.最后,总结当前服务器无感知计算性能优化技术所面临的问题和挑战,并展望未来可能的发展方向.

关键词：服务器无感知计算函数即服务云函数云计算性能优化

Effect of rotation angle on surface morphology, microstructure, and mechanical properties of Inconel 718 alloy fabricated by high power laser powder bed fusion

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Journal of Materials Science & Technology 2023年第23期154卷 30-42页

作者： qiao zhong Kaiwen Wei Taoyuan Ouyang Xiangyou Li Xiaoyan Zeng Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China Beijing Research Institute of Telemetry Beijing 100076 China

Rotation angle of the laser scan direction between two adjacent layers is a key controlling parameter during the high-power (≥ 1 kW) laser powder bed fusion (HP-LPBF) process. This study investigates the influences of rotation angles (θ = 0°, 45°, 90°, 105°) on the surface morphology, microstructure, and mechanical properties of Inconel 718 (IN718) alloy produced by HP-LPBF. Results show that adopting low rotation angles (e.g., 0° and 45°) is prone to relatively poor surface finish and lack-of-fusion defects, whereas adopting high rotation angles (e.g., 90° and 105°) induces smaller surface roughness and better relative density. Each case reveals a noticeable edge effect but the maximal heights witness a downward trend with the increase of rotation angle. There are some minor differences in the primary dendrite arm spacing and grain morphology by varying the rotation angles. Moreover, the tensile property is slightly enhanced as the rotation angle increases. The present work suggests that high rotation angles like 90° and 105° would probably be more favorable for the 1 kW HP-LPBF process than rotation angles with relatively low values.

关键词： High-power laser powder bed fusion Rotation angle Surface morphology Microstructure Mechanical properties Inconel 718 alloy

Numerical Simulation of Influence of Casting Speed Variation on Surface Fluctuation of Molten Steel in Mold

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Journal of Iron and Steel Research International 2010年第8期17卷 15-19页

作者： ZHANG qiao-ying WANG Xin-hua Ma'anshan Iron and Steel Co Ltd Ma'anshan 243000 Anhui China University of Science and Technology Beijing Beijing 100081 China

The influences of casting speed variation on surface fluctuation of the molten steel in mold during continuous casting were investigated with numerical simulation *** was found that when the casting speed was evenly decreased from 1.4 m·min-1 to 0.6 m·min-1,the increase of the surface fluctuation of the molten steel in mold was observed only on time that was at the start of casting speed ***,in experiment of increasing casting speed evenly from 0.6 m·min-1 to 1.4 m·min-1,the increase of the surface fluctuation of the molten steel in mold was observed only at the time when the casting speed was stopped to increase after it had been increased to 1.4 m·*** surface fluctuation of the molten steel in mold which was produced during the casting speed evenly increasing or decreasing period and at the time when increasing or decreasing the casting speed at low casting speed level（0.6 m·min-1）,the influence of casting speed change is very *** addition,it is found that,at high casting speed level（1.4 m·min-1）,even a little change of casting speed could result in remarkable increase of the surface ***,at high casting speed,changing casting speed should be avoided or much slower speed changing rate should be used.

关键词： unsteady continuous casting mold casting speed surface fluctuation numerical simulation

Properties of phosphate glass waste forms containing fluorides from a molten salt reactor

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Nuclear Science and Techniques 2016年第3期27卷 96-102页

作者： Ya-Ping Sun Xiao-Bin Xia Yan-Bo qiao zhong-Qi Zhao Hong-Jun Ma Xue-Yang Liu Zheng-hua Qian Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Radioactive fluoride wastes are generated during the operation of molten salt reactors(MSRs) and reprocessing of their spent *** of these wastes in borosilicate glass is not feasible because of the very low solubility of fluorides in this *** candidates are thus an active topic of research including phosphatebased glasses,crystalline ceramics,and hybrid glass-ceramic *** this study,mixed fluorides were employed as simulated MSRs waste and incorporated into sodium aluminophosphate glass to obtain phosphate-based waste *** waste forms were characterized by X-ray diffraction,Raman spectroscopy,and scanning electron *** tests were performed in deionized water using the product consistency test A *** study demonstrates that up to 20 mol%of simulated radioactive waste can be introduced into the NaA1 P glass matrix,and the chemical durability is much better than that of *** addition of Fe_2O_3 in the NaAlP glass matrix results in increases of the chemical durability at the expense of fluoride loading(to 6.4 mol%).Phosphate glass vitrification of radioactive waste containing fluorides is a potential method to treat and dispose of MSR wastes.

关键词：磷酸盐玻璃玻璃废物含氟化物放射性废物处理扫描电子显微镜熔盐堆硼硅酸盐玻璃化学耐久性

ON SMOOTH LU DECOMPOSITIONS WITH APPLICATIONS TO SOLUTIONS OF NONLINEAR EIGENVALUE PROBLEMS

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Journal of Computational Mathematics 2010年第6期28卷 745-766页

作者： hua Dai zhong-Zhi Bai Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

We study the smooth LU decomposition of a given analytic functional A-matrix A（A） and its block-analogue. Sufficient conditions for the existence of such matrix decompositions are given, some differentiability about certain elements arising from them are proved, and several explicit expressions for derivatives of the specified elements are provided. By using these smooth LU decompositions, we propose two numerical methods for computing multiple nonlinear eigenvalues of A（A）, and establish their locally quadratic convergence properties. Several numerical examples are provided to show the feasibility and effectiveness of these new methods.

关键词： Matrix-valued function Smooth LU decomposition Pivoting Nonlinear eigenvalue problem Multiple eigenvalue Newton method.

CHARACTERISTICS OF ZONAL ANOMALY OF ANNUAL PRECIPITATION IN THE NORTHEASTERN CHINA

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Chinese Geographical Science 2004年第4期14卷 320-325页

作者： YANMin-hua DENGWei CHENPan-qin LIANGLi-qiao NortheastInstituteofGeographyandAgriculturalEcology ChineseAcademyofSciencesChangchun130012P.R.China／／GraduateSchoolofChineseAcademyofSciencesBeijing100039P.R.China BureauofScienceandTechnologyforResourcesandEnvironment ChineseAcademyofScieneesBeijing100864P.R.China

The characteristics of zonal anomaly and change rule of temporal distribution of annual precipitation in the northeastern China are revealed in this paper with EOF (Empirical Orthogonal Function) and REOF (Rotated Empirical Orthogonal Function) methods and results are drawn in the standard relief maps with GIS technology for practical application. Data used in the study were obtained from 208 meteorological stations over the northeastern China from 1961 to 2001. EOF results show that the first 3 loading vectors could give entire spatial anomaly structure of annual precipitation. In the Northeast Plain including the Songneng Plain and the Liaohe Plain, there is a regional compatibility (whether wet or dry) of annual precipitation change and this precipitation pattern has occurred since the late 1980s to the present. There also exist annual precipitation patterns of wet (or dry) in south and dry (or wet) in north and wet (or dry) in east and dry (or wet) in west. REOF results display 8 principal precipitation anomaly areas by the first 8 rotated loading vectors: the west plain, the Liaodong hills, the Sanjiang Plain, the Liaoxi hills, the Changbai Mountains, the Hulun Buir Plateau, the southwest plateau and the Liaodong Peninsula.

关键词： annual precipitation northeastern China zonal anomaly precipitation characteristics

ON EIGENVALUE BOUNDS AND ITERATION METHODS FOR DISCRETE ALGEBRAIC RICCATI EQUATIONS

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Journal of Computational Mathematics 2011年第3期29卷 341-366页

We derive new and tight bounds about the eigenvalues and certain sums of the eigenvalues for the unique symmetric positive definite solutions of the discrete algebraic Riccati equations. These bounds considerably improve the existing ones and treat the cases that have been not discussed in the literature. Besides, they also result in completions for the available bounds about the extremal eigenvalues and the traces of the solutions of the discrete algebraic Riccati equations. We study the fixed-point iteration methods for com- puting the symmetric positive definite solutions of the discrete algebraic Riccati equations and establish their general convergence theory. By making use of the Schulz iteration to partially avoid computing the matrix inversions, we present effective variants of the fixed-point iterations, prove their monotone convergence and estimate their asymptotic convergence rates. Numerical results show that the modified fixed-point iteration methods are feasible and effective solvers for computing the symmetric positive definite solutions of the discrete algebraic Riccati equations.

关键词： Discrete algebraic Riccati equation Symmetric positive definite solution Eigenvalue bound Fixed-point iteration Convergence theory.