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Detection of Perfect Stealthy Attacks on Cyber-Physical Systems Subject to Measurement Quantizations: A Watermark-Based Strategy

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 114-125页

作者： Yu-Ang Wang Zidong Wang Lei zou Bo Shen Hongli Dong the College of Information Science and Technology Donghua University the Engineering Research Center of Digitalized Textile and Fashion Technology Ministry of Education IEEE the College of Electrical Engineering and Automation Shandong University of Science and Technology the Department of Computer Science Brunel University London Uxbridge the Sanya Offshore Oil and Gas Research Institute Northeast Petroleum University the Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum University

In this paper, the attack detection problem is investigated for a class of closed-loop systems subjected to unknownbutbounded noises in the presence of stealthy attacks. The measurement outputs from the sensors are quantized before transmission.A specific type of perfect stealthy attack, which meets certain rather stringent conditions, is taken into account. Such attacks could be injected by adversaries into both the sensor-toestimator and controller-to-actuator channels, with the aim of disrupting the normal data flow. For the purpose of defending against these perfect stealthy attacks, a novel scheme based on watermarks is developed. This scheme includes the injection of watermarks(applied to data prior to quantization) and the recovery of data(implemented before the data reaches the estimator).The watermark-based scheme is designed to be both timevarying and hidden from adversaries through incorporating a time-varying and bounded watermark signal. Subsequently, a watermark-based attack detection strategy is proposed which thoroughly considers the characteristics of perfect stealthy attacks,thereby ensuring that an alarm is activated upon the occurrence of such attacks. An example is provided to demonstrate the efficacy of the proposed mechanism for detecting attacks.

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Water quality evaluation of Haihe River with fuzzy similarity measure methods

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Journal of Environmental Sciences 2013年第10期25卷 2041-2046页

作者： Xiaojing Wang Zhihong zou Hui zou School of Economic and Management Beihang University Department of Applied Mathematics College of ScienceChina Agricultural University

Fuzzy similarity measures, which are used to judge the closeness of two fuzzy sets, are presented to evaluate the water quality of the Haihe River. Based on the membership functions and coefficient of variation as the weights, four fuzzy similarity measures （including Lattice similarity measure, Hamming similarity measure, Euclidean similarity measure and the max-min similarity measure） are used to classify the 299 samples into the proper water quality standard ranks. The results are compared with the traditional distance discriminant methods. The calculation of two traditional distance discriminant methods （both Euclidean distance and absolute value distance） is also based on the use of coefficients of variation as the weights. Without the Lattice similarity measure, for this method loses some information, the correct assignment of samples classified into the same water quality ranks is 75.92% with the other three similarity measures and two distance discriminant methods. This result shows the reliability of the five methods. Only considering the three similarity measures, there were only 1.01% of the samples that did not classify to the same ranks, while the corresponding ratio of the two distance discriminant methods was 5.69%. The results of leave-one-out cross validation show that more than 88% of the samples are classified to the proper ranks, which demonstrates that the similarity measures are suitable to evaluate the water quality of the Haihe River.

关键词： similarity measure distance discriminant coefficient of variation membership function

Recasting theory of elasticity with micro-finite elements

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Acta Mechanica Sinica 2015年第5期31卷 679-684页

作者： Wennan zou Institute for Advanced Study Nanchang University

In the classical theory of elasticity,a body is initially modeled as a homogeneous and dense assemblage of constituent ＂material particles＂.The kernel concept of elastic deformation is the displacement of the particle that associates the current configuration with the reference *** this paper,we exploit an alternative constituent ＂micro-finite element＂,and use the stretch of the element as the essential quality to recast the theory of *** should be realized that such a treatment means that the elastic body can be modeled as a finite covering of elements and consequently characterized by a *** recasting of the elasticity theory becomes more feasible for dealing with defects and topological evolution.

关键词： Micro-finite element Stretch Displacement Relative rotation Compatibility condition

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民国报刊视野中的陈方恪研究

湖北科技学院学报 2025年第1期45卷 19-25页

作者：邹艳徐清南昌大学人文学院江西南昌330031

学界多以“才子”与“浪子”评判陈方恪,前者是指他古典诗词创作的才能,以及文献整理与鉴别的学识,后者是指其在年轻时生活上的放纵以及履历上的任伪职。民国报刊收藏了有关陈方恪的图片、诗作、序文等,这些史料有助于打破学界对陈方恪... 详细信息

学界多以“才子”与“浪子”评判陈方恪,前者是指他古典诗词创作的才能,以及文献整理与鉴别的学识,后者是指其在年轻时生活上的放纵以及履历上的任伪职。民国报刊收藏了有关陈方恪的图片、诗作、序文等,这些史料有助于打破学界对陈方恪评价的“定形”。陈方恪不仅追求雅致的风范而且还具有救亡图存的责任意识,并将其书写进文学创作中。而报刊文献中的《适屦集》序文和追和王国维之创作,展现了陈方恪反映本我、追求创新的文学创作理念。

关键词：民国报刊陈方恪《适屦集》

Performance analysis of mobile ad hoc networks under flooding attacks

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Journal of Systems Engineering and Electronics 2011年第2期22卷 334-339页

作者： Ping Yi Futai zou Yan zou Zhiyang Wang School of Information Security Engineering Shanghai Jiaotong University Shanghai 200030 P. R. China The State Key Laboratory of Integrated Services Networks Xidian University Xi'an 710071 P. R. China

Due to their characteristics of dynamic topology, wireless channels and limited resources, mobile ad hoc networks are particularly vulnerable to a denial of service （DoS） attacks launched by intruders. The effects of flooding attacks in network simulation 2 （NS2） and measured performance parameters are investigated, including packet loss ratio, average delay, throughput and average number of hops under different numbers of attack nodes, flooding frequency, network bandwidth and network size. Simulation results show that with the increase of the flooding frequency and the number of attack nodes, network performance sharply drops. But when the frequency of flooding attacks or the number of attack nodes is greater than a certain value, performance degradation tends to a stable value.

关键词： mobile ad hoc network security flooding attack.

Electromagnetic Characteristic of Twin-wire Indirect Arc Welding

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 123-131页

作者： SHI Chuanwei zou Yong zou Zengda WU Dongting Key Laboratory of Liquid Structure and Heredity of Materials Shandong University

Traditional welding methods are limited in low heat input to workpiece and high welding wire melting rate. Twin-wire indirect arc（TWIA） welding is a new welding method characterized by high melting rate and low heat input. This method uses two wires one connected to the negative electrode and another to the positive electrode of a direct-current（DC） power source. The workpiece is an independent, non-connected unit. A three dimensional finite element model of TWIA is devised. Electric and magnetic fields are calculated and their influence upon TWIA behavior and the welding process is discussed. The results show that with a 100 A welding current, the maximum temperature reached is 17 758 K, arc voltage is 14.646 V while maximum current density was 61 A/mm2 with a maximum Lorene force of 84.5 ~tN. The above mentioned arc parameters near the cathode and anode regions are far higher than those in the arc column region. The Lorene force is the key reason for plasma velocity direction deviated and charged particles flowed in the channel formed by the cathode, anode and upper part of arc column regions. This led to most of the energy being supplied to the polar and upper part of arc column regions. The interaction between electric and magnetic fields is a major determinant in shaping TWIA as well as heat input on the workpiece. This is a first study of electromagnetic characteristics and their influences in the TWIA welding process, and it is significant in both a theoretical and practical sense.

关键词： twin-wire indirect arc welding electromagnetic simulation

UiLog： Improving Log-Based Fault Diagnosis by Log Analysis

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Journal of Computer Science & Technology 2016年第5期31卷 1038-1052页

作者： De-Qing zou Services Computing Technology and System Laboratory Huazhong University of Science and Technology Wuhan ~3007~ China Big Data Technology and System Laboratory Huazhong University of Science and Technology Wuhan 430074 China Cluster and Grid Computing Laboratory Huazhong University of Science and Technology Wuhan 430074 China School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

In modern computer systems, system event logs have always been the primary source for checking system status. As computer systems become more and more complex, the interaction between software and hardware increases frequently. The components will generate enormous log information, including running reports and fault information. The sheer quantity of data is a great challenge for analysis relying on the manual method. In this paper, we implement a management and analysis system of log information, which can assist system administrators to understand the real-time status of the entire system, classify logs into different fault types, and determine the root cause of the faults. In addition, we improve the existing fault correlation analysis method based on the results of system log classification. We apply the system in a cloud computing environment for evaluation. The results show that our system can classify fault logs automatically and effectively. With the proposed system, administrators can easily detect the root cause of faults.

关键词： fault diagnosis system event log log classification fault correlation analysis

Co-design for an SoC embedded network controller

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 591-596页

作者： zou Lian-ying zou Xue-cheng Department of Electronic Science ＆ Technology Huazhong University of Science ＆ Technology Wuhan 430074 China

With the development of Ethernet systems and the growing capacity of modem silicon technology, embedded communication networks are playing an increasingly important role in embedded and safety critical systems. Hardware/software co-design is a methodology for solving design problems in processor based embedded systems. In this work, we implemented a new 1-cycle pipeline microprocessor and a fast Ethemet transceiver and established a low cost, high performance embedded network controller, and designed a TCP/IP stack to access the Intemet. We discussed the hardware/software architecture in the forepart, and then the whole system-on-a-chip on Altera Stratix EP1S25F780C6 device. Using the FPGA environment and SmartBit tester, we tested the system＇s throughput. Our simulation results showed that the maximum throughput of Ethemet packets is up to 7 Mbps, that of UDP packets is up to 5.8 Mbps, and that of TCP packets is up to 3.4 Mbps, which showed that this embedded system can easily transmit basic voice and video signals through Ethemet, and that using only one chip can realize that many electronic devices access to the Intemet directly and get high performance.

关键词： System-on-Chip (SoC) Embedded Microprocessor Network controller TCP/IP Co-design

Relationships of along-the-track local variations of GPS RO impact parameter to strong local vertical gradient of wet refractivity in the tropics

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Science China Earth Sciences 2021年第11期64卷 2015-2026页

作者： Shengpeng YANG Xiaolei zou Joint Center of Data Assimilation for Research and Application Nanjing University of Information Science&TechnologyNanjing 210044China

Atmospheric refractivity fields are more strongly affected by more water vapor in the tropical lower troposphere than *** this study,based on model simulations,we first collocated the radio occultation(RO)data in 2009 from the Constellation Observing System for Meteorology,Ionosphere,and Climate(COSMIC)with CloudSat cloud profiling radar *** then investigate where and why a RO ray path intersects with other simulated rays of impact heights above and/or below the impact height of the *** the European Centre for Medium-Range Weather Forecasts ERA5 reanalysis as input to a raytracing observation operator,we show that the simulated impact parameters could vary along the ray in the tropical lower *** brevity,an intersection of a GPS RO ray path with rays above it or below it or both will be called an impact *** overlapping simulated ray trajectories over the vertical and horizontal gradients of refractivity in 2D occultation planes,impact multipath occurrences are vividly *** results show that the impact multipath is caused mostly by strong local vertical gradients of atmospheric wet refractivity mostly within 300 km horizontal distances from their perigee *** impact multipath occurs more frequently below 5-km impact height,with a maximum occurrence around the 3.4 km impact height(about 1.8 km geometric height).It is shown that both the simulated impact multipath phenomena and locally strong vertical gradients of wet refractivity are found in both cloudy and clear-sky conditions,and most frequently in presences of stratocumulus clouds.

关键词： GPS RO Multipath Troposphere