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Using Event-Based Method to Estimate Cybersecurity Equilibrium

IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 455-467页

作者： Zhaofeng Liu Ren Zheng Wenlian Lu Shouhuai Xu the School of Mathematical Sciences Fudan UniversityShanghai 200433China the Artificial Intelligence Laboratory SAIC Motor Corporation LimitedShanghai 200041 SAIC Intelligent Technology(Shanghai)corporation Limited Shanghai 200433China the School of Mathematical Sciences Fudan Universityand Shanghai Center for Mathematical SciencesFudan Universityand also with Shanghai Key Laboratory for Contemporary Applied MathematicsShanghai 200433China the Department of Computer Science University of Texas at San AntonioSan Antonio TX 78249 USA

Estimating the global state of a networked system is an important problem in many application *** classical approach to tackling this problem is the periodic(observation)method,which is inefficient because it often observes states at a very high *** inefficiency has motivated the idea of event-based method,which leverages the evolution dynamics in question and makes observations only when some rules are triggered(i.e.,only when certain conditions hold).This paper initiates the investigation of using the event-based method to estimate the equilibrium in the new application domain of cybersecurity,where equilibrium is an important metric that has no closed-form *** specifically,the paper presents an event-based method for estimating cybersecurity equilibrium in the preventive and reactive cyber defense dynamics,which has been proven globally *** presented study proves that the estimated equilibrium from our trigger rule i)indeed converges to the equilibrium of the dynamics and ii)is Zeno-free,which assures the usefulness of the event-based *** examples show that the event-based method can reduce 98%of the observation cost incurred by the periodic *** order to use the event-based method in practice,this paper investigates how to bridge the gap between i)the continuous state in the dynamics model,which is dubbed probability-state because it measures the probability that a node is in the secure or compromised state,and ii)the discrete state that is often encountered in practice,dubbed sample-state because it is sampled from some *** bridge may be of independent value because probability-state models have been widely used to approximate exponentially-many discrete state systems.

关键词： Cybersecurity dynamics cybersecurity equilibrium event-based method global state estimation preventive and reactive cyber defense dynamics

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Study on load performance of electric motor system used in hybrid electric vehicle

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High Technology Letters 2010年第1期16卷 63-66页

作者：李雯 Zhang Chengning Wang Zhifu Gao Lei National Engineering Laboratory for Electric Vehicle Beijing Institute of Technology Beijing 100081 P.R. China New Energy Vehicle Division SAIC motor corporation Limited Shanghai 201804 P.R. China

The performance of the power assist, global optimization solved by dynamic programming （DP） method, Chery and Insight control strategies are analyzed using the mild parallel hybrid electric vehicle （PHEV） model based on Insight structure. The influence of the four control strategies to the load power of the electric motor system used on parallel hybrid electric vehicle is studied. It is found that 80 percent of the motor load power points are under 1/5 of the electric peak power. The motor load power of the power assist control strategy is distributed in the widest range during generating operation, and the motor load power of the global optimization control strategy has the smallest one.

关键词： parallel hybrid electric vehicle (PHEV) management strategy motor load power

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Uncertainty analysis and probabilistic design optimization of hybrid rocket motors for manned lunar landing

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Science China(Technological Sciences) 2015年第7期58卷 1234-1241页

作者： ZHU Hao TIAN Hui CAI GuoBiao BAO WeiMin School of Astronautics Beihang University China Aerospace Science and Technology corporation

To obtain a conceptual design for a hybrid rocket motor(HRM)to be used as the Ascent Propulsion System in the Apollo lunar module,the deterministic design optimization(DDO)method is applied to the HRM *** on the results of an uncertainty analysis of HRMs,an uncertainty-based design optimization(UDO)method is also adopted to improve the design *** HRM design process,which is a multidisciplinary system,is analyzed,and a mathematical model for the system design is established to compute the motor performance from the input parameters,including the input variables and model *** input parameter uncertainties are quantified,and a sensitivity analysis of the model parameter uncertainties is conducted to identify the most important model parameter uncertainties for *** DDO and probabilistic UDO methods are applied to conceptual designs for an HRM to be used as a substitute for the liquid rocket motor(LRM)of the Ascent Propulsion *** conceptual design results show that HRMs have several advantages as an alternative to the LRM of the Ascent Propulsion System,including nontoxic propellant combination,small motor volume,and comparable functions,such as restarting and *** of the DDO and UDO results indicate that the UDO method achieves more robust and reliable optimal designs than the DDO *** probabilistic UDO method can be used to develop better conceptual designs for HRMs.

关键词： hybrid rocket motor deterministic design optimization uncertainty-based design optimization sensitivity analysis manned lunar landing

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Uncertainty analysis and design optimization of hybrid rocket motor powered vehicle for suborbital flight

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Chinese Journal of Aeronautics 2015年第3期28卷 676-686页

作者： Zhu Hao Tian Hui Cai Guobiao Bao Weimin School of Astronautics Beihang University China Aerospace Science and Technology corporation

Abstract In this paper, we propose an uncertainty analysis and design optimization method and its applications on a hybrid rocket motor （HRM） powered vehicle. The multidisciplinary design model of the rocket system is established and the design uncertainties are quantified. The sensitivity anal- ysis of the uncertainties shows that the uncertainty generated from the error of fuel regression rate model has the most significant effect on the system performances. Then the differences between deterministic design optimization （DDO） and uncertainty-based design optimization （UDO） are discussed. Two newly formed uncertainty analysis methods, including the Kriging-based Monte Carlo simulation （KMCS） and Kriging-based Taylor series approximation （KTSA）, are carried out using a global approximation Kriging modeling method. Based on the system design model and the results of design uncertainty analysis, the design optimization of an HRM powered vehicle for suborbital flight is implemented using three design optimization methods： DDO, KMCS and KTSA. The comparisons indicate that the two UDO methods can enhance the design reliability and robustness. The researches and methods proposed in this paper can provide a better way for the general design of HRM powered vehicles.

关键词： Design optimization Hybrid rocket motor Kriging model Uncertainty analysis Uncertainty-based designoptimization

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Real-Time Instability Detection of Centrifugal Compressors Based on motor Speed Measurements

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Journal of Thermal Science 2023年第1期32卷 310-329页

作者： CHEN Haoxiang ZHUGE Weilin QIAN Yuping ZHANG Yangjun LIU Hongdan State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Chongqing Jiangjin Shipbuilding Industry corporation China Shipbuilding Industry CorporationChongqing 402263China

Flow instability in the centrifugal compressor should be detected and avoided for stable and safe *** to the popularity of electric centrifugal compressors,instability detection could be achieved by measuring motor signals instead of traditional aerodynamic *** this paper,the feasibility of instability detection by motor signals(*** speed and phase current)was studied *** physical structure and control method of the electric centrifugal compressor were discussed to reveal the potential of instability detection by motor *** pressure signals and motor signals measured during unsteady experiments were analyzed in the time domain and frequency *** of these signals were then compared under different operating conditions to indicate the feasibility of instability detection by motor ***,the ability of Short-Time Fourier Transform(STFT)of rotating speed signals in real-time instability detection was *** showed that the rotating speed signal is a good alternate for instability detection in spite of signal distortion,while the phase current signal can only detect surge due to the low resolution of the *** on the variations of the amplitude and frequency of rotating speed signals,the real-time instability can be captured accurately by STFT with a window size of 0.5 ***,the interference caused by the controller can be removed by STFT.

关键词： centrifugal compressor instability detection real-time rotating speed STFT

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Current Achievements of Brain Controlled Vehicles

Current Achievements of Brain Controlled Vehicles

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2018中国汽车工程学会年会

作者： QIAN Jianshu BIE Weiwei LI Kai ZHANG Ruilin FANG Qiang Wuhan University DongFeng motor corporation Technical Center

We introduce the development of brain-controlled vehicles by summarizing certain academic achievements in recent ***,we summarize the most advanced technology of harmless Brain-Computer Interface that can be applied into such autonomous ***,we introduce the latest experiments on Brain-Computer Interface-Based Vehicles conducted by certain research ***,an anticipation on the trends of brain-controlled vehicles will be proposed based on the functions of the existing *** most advanced brain-controlled cars are able to be commanded by brain signals to move forward,stop,and turn left or right and choose a pre-stored *** of these functions only depend on brain signals,which means it doesn’t need the assistance of a *** to the related latest experiments,such autonomous cars performed well in laboratory conditions and simulated real-road *** analyzing the advantages and flaws of the existing vehicles,we anticipate that brain-controlled vehicles will respond more quickly with high ***’ s more,such autonomous cars will be convenient for all kinds of people.

关键词： brain-controlled vehicles brain-computer interface autonomous vehicles

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Semantic Segmentation-Based Road Marking Detection Using Around View Monitoring System

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 833-843页

作者： XU Hanqing YANG Ming DENG Liuyuan LI Hao WANG Chunxiang HAN Weibin YU Yuelong School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China SJTU-ParisTech Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China SAIC motor corporation Limited Shanghai 200041China

Road marking detection is an important branch in autonomous driving,understanding the road *** recent years,deep-learning-based semantic segmentation methods for road marking detection have been arising since they can generalize detection result well under complicated environments and hold rich pixel-level semantic ***,the previous methods mostly study the training process of the segmentation network,while omitting the time cost of manually annotating pixel-level ***,the pixel-level semantic segmentation results need to be fitted into more reliable and compact models so that geometrical information of road markings can be explicitly *** order to tackle the above problems,this paper describes a semantic segmentation-based road marking detection method using around view monitoring system.A semiautomatic semantic annotation platform is developed,which exploits an auxiliary segmentation graph to speed up the annotation process while guaranteeing the annotation accuracy.A segmentation-based detection module is also described,which models the semantic segmentation results for the more robust and compact *** proposed detection module is composed of three parts:vote-based segmentation fusion filtering,graph-based road marking clustering,and road-marking *** under various scenarios show that the semantic segmentation-based detection method can achieve accurate,robust,and real-time detection performance.

关键词： autonomous driving semantic segmentation road marking detection

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Fuzzy Matrix Theory Application on Module Division for Steering System

Fuzzy Matrix Theory Application on Module Division for Steer...

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2015中国汽车工程学会年会

作者： Dai Gang Chen Pingping Yang Chao Layout Department Dongfeng Motor Corporation Technology Center

Combining fuzzy matrix with passenger vehicle steering system,define geometiy relevance and calculate cluster coupling,distribute and classify the steering module.

关键词： steering system fuzzy matrix theory module partition

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Optimization of Front Windshield Lower Beam Welding Assembly Based on NVH Performance

Optimization of Front Windshield Lower Beam Welding Assembly...

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2014中国汽车工程学会年会

作者： Cheng Yanan Deng Feng Zhang Ping Liu Hao NVH Institute Technology CenterDongfeng Motor Corporation

To meet the need of pedestrian protection and ensure the vehicle has good energy absorption when the head hit the windshield,the front windshield lower beam welding assembly was required to be designed open *** a result,the vibration of the front windshield and firewall became strong,and the interior booming noise problem could be *** order to solve this problem,the simulation method was carried out to optimize the booming noise in this paper,the vibration of the front windshield and firewall was reduced by enhancing the windshield support structure and meanwhile,the noise transfer function was *** improved solution was validated in real *** test also shows that enhancing windshield support structure can effectively improve the high speed booming noise.

关键词： lower beam welding assembly booming noise stiffness transfer function

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Simulation and Experiment for Oxygen-enriched Combustion Engine Using Liquid Oxygen to Solidify CO2

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 188-194页

作者： LIU Yongfeng JIA Xiaoshe PEI Pucheng LU Yong YI Li SHI Yan Beijing Research Centre of Sustainable Energy and Building Beijing University of Civil Engineering and Architecture Beijing 100044 China State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China New Technologies and Materials Department BAIC MOTOR Corporation Ltd. Beijing Automotive Technology Center Beijing 101300 China

For capturing and recycling of CO2 in the internal combustion engine, Rankle cycle engine can reduce the exhaust pollutants effectively under the condition of ensuring the engine thermal efficiency by using the techniques of spraying water in the cylinder and optimizing the ignition advance angle. However, due to the water spray nozzle need to be installed on the cylinder, which increases the cylinder head design difficulty and makes the combustion conditions become more complicated. In this paper, a new method is presented to carry out the closing inlet and exhaust system for internal combustion engines. The proposed new method uses liquid oxygen to solidify part of cooled CO2 from exhaust system into dry ice and the liquid oxygen turns into gas oxygen which is sent to inlet system. The other part of CO2 is sent to inlet system and mixed with oxygen, which can reduce the oxygen-enriched combustion detonation tendency and make combustion stable. Computing grid of the IP52FMI single-cylinder four-stroke gasoline-engine is established according to the actual shape of the combustion chamber using KIVA-3V program. The effects of exhaust gas recirculation （EGR） rate are analyzed on the temperatures, the pressures and the instantaneous heat release rates when the EGR rate is more than 8%. The possibility of enclosing intake and exhaust system for engine is verified. The carbon dioxide trapping device is designed and the IP52FMI engine is transformed and the CO2 capture experiment is carried out. The experimental results show that when the EGR rate is 36% for the optimum EGR rate. When the liquid oxygen of 35.80-437.40 g is imported into the device and last 1-20 min, respectively, 21.50-701.30 g dry ice is obtained. This research proposes a new design method which can capture CO2 for vehicular internal combustion engine.

关键词： internal combustion Rankle cycle engine CO2 emission reduction carbon-sequestration with liquid oxygen,KIVA-3V program oxygen-enriched combustion numerical simulation experiments

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