The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were...The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were studied systematically in this paper.The slag structure,melting temperature,and viscous characteristics were investigated by Fourier transform infrared(FTIR)spectroscopy,Raman spectroscopy,Fact Sage calculation,and viscosity measurements.Experimental results show that the increase of Fe_(2)O_(3)content(3.8wt%–16.6wt%),the mass ratio of CaO/SiO_(2)(m(CaO)/m(SiO_(2)),0.5–1.3),and the mass ratio of SiO_(2)/Al_(2)O_(3)(m(SiO_(2))/m(Al_(2)O_(3)),1.0–5.0)can promote the depolymerization of silicate network,and the presence of a large amount of Fe_(2)O_(3)in form of tetrahedral and octahedral units ensures the charge compensation of Al^(3+)ions and makes Al_(2)O_(3)only behave as an acid oxide.Thermodynamic calculation and viscosity measurements show that with the increase of Fe_(2)O_(3)content,m(Ca O)/m(SiO_(2)),and m(SiO_(2))/m(Al_(2)O_(3)),the depolymerization of silicate network structure and low-melting-point phase transformation first occur within the slag,leading to the decrease in melting point and viscosity of the slag,while further increase causes the formation of high-melting-point phase and a resultant re-increase in viscosity and melting point.Based on experimental analysis,the preferred slag composition with low polymerization degree,viscosity,and melting point is as follows:Fe_(2)O_(3)content of 10.2wt%–13.4wt%,m(CaO)/m(SiO_(2))of 0.7–0.9 and m(SiO_(2))/m(Al_(2)O_(3))of 3.0–4.0.This work provides a theoretical support for slag design in co-smelting process of SAC and CBES.展开更多
Recently,automotive intrusion detection systems(IDSs)have emerged as promising defense approaches to counter attacks on in-vehicle networks(IVNs).However,the effectiveness of IDSs relies heavily on the quality of the ...Recently,automotive intrusion detection systems(IDSs)have emerged as promising defense approaches to counter attacks on in-vehicle networks(IVNs).However,the effectiveness of IDSs relies heavily on the quality of the datasets used for training and evaluation.Despite the availability of several datasets for automotive IDSs,there has been a lack of comprehensive analysis focusing on assessing these datasets.This paper aims to address the need for dataset assessment in the context of automotive IDSs.It proposes qualitative and quantitative metrics that are independent of specific automotive IDSs,to evaluate the quality of datasets.These metrics take into consideration various aspects such as dataset description,collection environment,and attack complexity.This paper evaluates eight commonly used datasets for automotive IDSs using the proposed metrics.The evaluation reveals biases in the datasets,particularly in terms of limited contexts and lack of diversity.Additionally,it highlights that the attacks in the datasets were mostly injected without considering normal behaviors,which poses challenges for training and evaluating machine learning-based IDSs.This paper emphasizes the importance of addressing the identified limitations in existing datasets to improve the performance and adaptability of automotive IDSs.The proposed metrics can serve as valuable guidelines for researchers and practitioners in selecting and constructing high-quality datasets for automotive security applications.Finally,this paper presents the requirements for high-quality datasets,including the need for representativeness,diversity,and balance.展开更多
Free quenching of automotive leaf springs is a new technology that has gradually started to be applied in the industry in China in recent years.Only a few manufacturers are applying it in the industry.Through more tha...Free quenching of automotive leaf springs is a new technology that has gradually started to be applied in the industry in China in recent years.Only a few manufacturers are applying it in the industry.Through more than half a year of on-site practice,the changes in the hot forming of spring plates before free quenching have been explored,and finally a heat treatment process that meets the production requirements of our company has been developed,achieving normal production.展开更多
In recent years, with attention paid to global environmental problems, there have been requirements for continuous improvement of automobile fuel economy and exhaust gas purification rate. The properties of the ferrit...In recent years, with attention paid to global environmental problems, there have been requirements for continuous improvement of automobile fuel economy and exhaust gas purification rate. The properties of the ferritic stainless steels (FSS) used to make automobile parts have been improved. This paper introduces the construction of automotive exhaust systems and describes their main failure behaviors and corrosion evaluation procedures.展开更多
Network and software integration pose severe challenges in cyber-security for controller area network(CAN)-based automotive cyber-physical system(ACPS), therefore we employ message authentication code(MAC) to defend C...Network and software integration pose severe challenges in cyber-security for controller area network(CAN)-based automotive cyber-physical system(ACPS), therefore we employ message authentication code(MAC) to defend CAN against masquerade attack, but the consequent bandwidth overhead makes it a necessity to find the tradeoff among security, real-time and bandwidth utilization for signal packing problem(SPP) of CAN.A mixed-security signal model is firstly proposed to formally describe the properties and requirements on security and real-time for signals, and then a mixed-integer linear programming(MILP)formulation of SPP security-aware signal packing(SASP) is implemented to solve the tradeoff problem, where the bandwidth utilization is improved and the requirements in both security and real-time are met. Experiments based on both society of automotive engineers(SAE) standard signal set and simulated signal set showed the effectiveness of SASP by comparing with the state-of-the-art algorithm.展开更多
China is currently vigorously implementing the“energy conservation and emission reduction”and“dual carbon”strategies.As the most resource-advantaged light metal material in China,Magnesium(Mg)alloy is progressivel...China is currently vigorously implementing the“energy conservation and emission reduction”and“dual carbon”strategies.As the most resource-advantaged light metal material in China,Magnesium(Mg)alloy is progressively expanding its application in automobile,rail transportation,aerospace,medical,and electronic products.Chongqing University,Shanghai Jiaotong University,and Australian National University have conducted extensive research on the preparation,properties,and processes of Mg alloys.In the past 20 years,the proportion of Mg alloy in the automotive industry has gradually expanded,whereas currently the design and development of Mg alloy parts for automobiles has rarely been reported.Thus,the application models and typical parts cases of Mg alloy are summarized mainly from the four systems of the whole vehicle(body system,chassis system,powertrain system,interior,and exterior system).Subsequently,two actual original equipment manufacturers(OEM)cases are used to introduce the development logic of reliable die-cast Mg alloy,including forward design,formability analysis,process design analysis,structural redesign,manufacturing,and testing,aiming to share the methods,processes,and focus of attention of automotive OEMs for developing Mg alloy parts to enhance the confidence and motivation of applying Mg alloy in automotive field.Eventually,the multiple challenges faced by Mg alloy materials are sorted out and how to face these challenges are discussed.National policies and regulations,environmental protection and energy saving,and consumer demand will continue to promote the application of Mg.展开更多
Automobiles evolved from primarily mechanical to electro-mechanical,or mechatronic,vehicles.For example,carburetors have been replaced by fuel injection and air-fuel ratio control,leading to order of magnitude improve...Automobiles evolved from primarily mechanical to electro-mechanical,or mechatronic,vehicles.For example,carburetors have been replaced by fuel injection and air-fuel ratio control,leading to order of magnitude improvements in fuel economy and emissions.Mechatronic systems are pervasive in modem automobiles and represent a synergistic integration of mechanics,electronics and computer science.They are smart systems,whose design is more challenging than the separate design of their mechanical,electronic and computer/control components.In this review paper,two recent methods for the design of mechatronic components are summarized and their applications to problems in automotive control are highlighted.First,the combined design,or co-design,of a smart artifact and its controller is considered.It is shown that the combined design of an artifact and its controller can lead to improved performance compared to sequential design.The coupling between the artifact and controller design problems is quantified,and methods for co-design are presented.The control proxy function method,which provides ease of design as in the sequential approach and approximates the performance of the co-design approach,is highlighted with application to the design of a passive/active automotive suspension.Second,the design for component swapping modularity(CSM)of a distributed controller for a smart product is discussed.CSM is realized by employing distributed controllers residing in networked smart components,with bidirectional communication over the network.Approaches to CSM design are presented,as well as applications of the method to a variable-cam-timing engine,and to enable battery swapping in a plug-in hybrid electric vehicle.展开更多
The requirements for automotive lighting systems,especially the light patterns ensuring driver perception,are based on criteria related to the headlamps,rather than the light perceived by drivers and road users.Conseq...The requirements for automotive lighting systems,especially the light patterns ensuring driver perception,are based on criteria related to the headlamps,rather than the light perceived by drivers and road users.Consequently,important factors such as pavement reflectance,driver age,or time of night,are largely ignored.Other factors such as presence of other vehicles,vehicle speed and weather conditions are considered by the Adaptive Driving Beam(ADB)and Adaptive Front-lighting System(AFS)respectively,though with no information regarding the visual perception of drivers and other road users.Evidently,it is simpler to simulate and measure the light emitted by the lamps than the light reflected by the pavement or emitted by other vehicles.However the current technology in cameras and light sensors,communication protocols,and control of Light Emitting Diodes(LED),combined with decision-making techniques applied to large amounts of data,can open a new era in the operation of headlamps and thus ensure the visual needs of drivers in real time and under actual road conditions.The solution lies in an interaction road-sensor-headlamp,which is not based on the light emitted by headlamps,but rather on the light perceived by the drivers.This study thus proposes a dual grid based on luminance and luminous intensity,which would manage the headlamps by optimizing driver perception and the safety of all road users.展开更多
The artificial intelligence is applied to the simulation of the automotive air-conditioning system ( AACS )According to the system's characteristics a model of AACS, based on neural network, is developed. Differen...The artificial intelligence is applied to the simulation of the automotive air-conditioning system ( AACS )According to the system's characteristics a model of AACS, based on neural network, is developed. Different control methods of AACS are discussed through simulation based on this model. The result shows that the neural- fuzzy control is the best one compared with the on-off control and conventional fuzzy control method.It can make the compartment's temperature descend rapidly to the designed temperature and the fluctuation is small.展开更多
To evaluate the software behavior of the electronic control unit (ECU) of automotive electrical parking brake (EPB), a software- in-the-loop (SiL) simulation system is built. The EPB is simulated by ARX (auto-r...To evaluate the software behavior of the electronic control unit (ECU) of automotive electrical parking brake (EPB), a software- in-the-loop (SiL) simulation system is built. The EPB is simulated by ARX (auto-regressive with auxiliary input) model, ARMAX (auto-regressive moving average with auxiliary input) model, and NNARMAX (neural network ARMAX) model. By system identification, the ARX(3,4,2), ARX(4,4,2), ARMAX(3,3,1,1), and ARMAX(4,4,3,2) models are derived. Validation results show that the four-order ARMAX model and the NNARMAX model better simulate the actuator of the EPB.展开更多
The ability to predict the weathering performance of the clearcoat system over a short period of time is essential for the design and development of coating production. Thus, the primary objective of the present study...The ability to predict the weathering performance of the clearcoat system over a short period of time is essential for the design and development of coating production. Thus, the primary objective of the present study is to investigate whether it is possible to predict the weathering performance of an automotive paint system through determination of surface roughness, Ra, and micro-hardness before and after various weathering exposure times (0, 24, 168, 336, 504, 672 hours) and when employing two different detergent materials (house-use detergent and car wash detergent). The data were analysed using a pair-sample t-Test, with 0.05 level of significance. It was found that the total net of degradation in the clearcoat level during the first 24 hours was Ra ≈ 30.3 nm (for surface roughness) and 1.358 HV (for the μ-hardness) when using the house-use detergent. In contrast, it was found to be Ra ≈ 4.6 nm (for surface roughness) and 1.133 HV (for μ-hardness) when using the car wash detergent. Also, increased time of weathering (up to 672 hours) increases the Ra and μ-hardness values. It can therefore be concluded that the effect of house-use detergent was more severe than that of car wash detergent on the clearcoat system.展开更多
Humidity can affect the attenuation of MEA(membrane electrode assembly), however, the relationship between humidity and MEA decays is complex and ambiguous in realistic application. Herein, we design a simulating auto...Humidity can affect the attenuation of MEA(membrane electrode assembly), however, the relationship between humidity and MEA decays is complex and ambiguous in realistic application. Herein, we design a simulating automotive protocol, performed on five single fuel cells under RH(relative humidity) 100%,RH 80%, RH 64%, and RH 40%, RH 10%, respectively, to study the relationship of MEA decays and humidity and suggest optimized humidity range to extend the durability. With the electrochemical impedance spectroscopy, cyclic voltammetry, X-ray fluorescence, X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, the four degradation mechanisms about catalyst layer, including Pt dissolution, Pt coarsening, carbon corrosion and ionomer degradation, are observed. Pt coarsening and carbon corrosion are accelerated by higher water content at high humidity. Ionomer degradation and Pt dissolution are enhanced in low humidity. With the linear sweep voltammetry, ion chromatography,nuclear magnetic resonance, tensile test and scan electron microscope, chemical and mechanical degradation in proton exchange membrane are all observed in these five fuels. Chemical degradation, characterized by membrane thinning and more fluoride loss, occurred markedly in RH 10%. Mechanical degradation, characterized by the non-uniformity thickness and bad mechanical properties, is more pronounced in RH 100%, RH 80%, RH 64%. These two degradations are in a moderate level in RH 40%. The research suggests that the RH range from 64% to 40% is conductive to mitigate the degradation of MEAs operated in automotive applications.展开更多
In automotive industries,panel acoustic contribution analysis(PACA)is used to investigate the contributions of the body panels to the acoustic pressure at a certain point of interest.Currently,PACA is implementedmostl...In automotive industries,panel acoustic contribution analysis(PACA)is used to investigate the contributions of the body panels to the acoustic pressure at a certain point of interest.Currently,PACA is implementedmostly by either experiment-based methods or traditional numerical methods.However,these schemes are effort-consuming and inefficient in solving engineering problems,thereby restraining the further development of PACA in automotive acoustics.In this work,we propose a PACA scheme using discontinuous isogeometric boundary element method(IGABEM)to build an easily implementable and efficient method to identify the relative acoustic contributions of each automotive body panel.Discontinuous IGABEMis more accurate and converges faster than continuous BEM and IGABEM in the interior sound pressure evaluation of automotive compartments.In this work,a contribution ratio is defined to estimate the relative acoustic contribution of the structure panels;it can be calculated by reusing the coefficient matrix that has already been generated in the sound pressure evaluation process.The utilization of the parallel technique enables the proposed method to be more efficient than conventional methods;it is validated in two numerical examples,including a car passenger compartment subjected to realistic boundary conditions.A sound pressure response experiment based on a steel box is conducted to verify the accuracy of the interior sound pressure calculation using discontinuous IGABEM.This work is expected to promote the practical process of IGABEM for application in automotive acoustic problems.展开更多
This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good resul...This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good results.Firstly,an electromagnetic(EM)wave NLOS multipath propagation model for vehicle scene is established.Subsequently,with the help of available multipath echoes,a complete NLOS vehicle localiza-tion algorithm is proposed.Finally,simulation and experimental results validate the effectiveness of the established EM wave propagation model and the proposed NLOS vehicle localization algorithm.展开更多
Modern vehicles are equipped with multiple Electronic Control Units(ECUs)that support various convenient driving functions,such as the Advanced Driver Assistance System(ADAS).To enable communication between these ECUs...Modern vehicles are equipped with multiple Electronic Control Units(ECUs)that support various convenient driving functions,such as the Advanced Driver Assistance System(ADAS).To enable communication between these ECUs,the Controller Area Network(CAN)protocol is widely used.However,since CAN lacks any security technologies,it is vulnerable to cyber attacks.To address this,researchers have conducted studies on machine learning-based intrusion detection systems(IDSs)for CAN.However,most existing IDSs still have non-negligible detection errors.In this paper,we pro-pose a new filtering-based intrusion detection system(FIDS)to minimize the detection errors of machine learning-based IDSs.FIDS uses a whitelist and a blacklist created from CAN datasets.The whitelist stores the cryptographic hash value of normal packet sequences to correct false positives(FP),while the blacklist corrects false negatives(FN)based on transmission intervals and identifiers of CAN packets.We evaluated the performance of the proposed FIDS by implementing a machine learning-based IDS and applying FIDS to it.We conducted the evaluation using two CAN attack datasets provided by the Hacking and Countermeasure Research Lab(HCRL),which confirmed that FIDS can effectively reduce the FP and FN of the existing IDS.展开更多
This study explored the synergistic interaction of sewage sludge(SS)and automotive paint sludge(PS)during co-pyrolysis for the optimized treatment of sewage sludge in cement kiln systems,utilizing thermogravimetric an...This study explored the synergistic interaction of sewage sludge(SS)and automotive paint sludge(PS)during co-pyrolysis for the optimized treatment of sewage sludge in cement kiln systems,utilizing thermogravimetric analysis(TGA)and thermogravimetric-mass spectrometry(TGA-MS).The result reveals the coexisting synergistic and antagonistic effects in the co-pyrolysis of SS/PS.The synergistic effect arises from hydrogen free radicals in SS and catalytic components in PS,while the main source of the antagonistic effect is that,during the mechanical mixing process,the SS/PS is converted from the particulate form into a dough-like rubbery which contributes to the film-forming effect,hindering the volatilization of volatile components.SS/PS co-pyrolysis reduces the yielding of tar production while increasing coke and gas.This study will provide some in-depth insights into the co-pyrolysis of SS/PS,and offer theoretical support for the subsequent research on the collaborative disposal processes in cement kilns.展开更多
本文采用S3C2440A和Windows Automotive 5.0设计了一种汽车导航系统。在硬件方面,给出了S3C2440A和LCD、GPS芯片的接口电路。在软件方面,详细介绍了驱动程序和操作系统的开发方法,并在Visual Studio 2005中成功开发了该系统的GPS信号测...本文采用S3C2440A和Windows Automotive 5.0设计了一种汽车导航系统。在硬件方面,给出了S3C2440A和LCD、GPS芯片的接口电路。在软件方面,详细介绍了驱动程序和操作系统的开发方法,并在Visual Studio 2005中成功开发了该系统的GPS信号测试程序。实验结果表明,该系统导航功能良好、可以运行多种导航软件、具有一定的汽车运行状况监控功能。展开更多
The vehicle industry is always in search of breakthrough energy-saving and emission-reduction technologies.In recent years,vehicle intelligence has progressed considerably,and researchers are currently trying to take ...The vehicle industry is always in search of breakthrough energy-saving and emission-reduction technologies.In recent years,vehicle intelligence has progressed considerably,and researchers are currently trying to take advantage of these developments.Here we consider the case of many vehicles forming a queue,i.e.,vehicles traveling at a predetermined speed and distance apart.While the majority of existing studies on this subject have focused on the influence of the longitudinal vehicle spacing,vehicle speed,and the number of vehicles on aerodynamic drag and fuel economy,this study considers the lateral offset distance of the vehicle queue.The group fuel consumption savings rate is calculated and analyzed.As also demonstrated by experimental results,some aerodynamic benefits exist.Moreover,the fuel consumption saving rate of the vehicle queue decreases as the lateral offset distance increases.展开更多
Instant noodles contain 16 to18 percent fat,including 11 percent from palm oil.Most people have no idea where palm oil comes from or what it is used for,but they could not live without it because it is so widely used ...Instant noodles contain 16 to18 percent fat,including 11 percent from palm oil.Most people have no idea where palm oil comes from or what it is used for,but they could not live without it because it is so widely used in personal hygiene products such as shampoo,tooth paste,facial cream,and soap.It is also an ingredient in automotive lubricants and food such as fried chicken,chocolate,and various pastries.展开更多
基金financially supported by the Guangzhou Basic and Applied Basic Research Project,China(No.202102020623)the Guangdong Academy of Sciences’Project of Science and Technology Development,China(No.2020 GDASYL-20200103101)+1 种基金the National Key Research and Development Program of China(No.2020YFC1908902)the Natural Science Foundation of Guangdong Province Project,China(No.2020A1515010729)。
文摘The metallurgical properties of the CaO–SiO_(2)–Al_(2)O_(3)–4.6wt%Mg O–Fe_(2)O_(3)slag system,formed by the co-treatment process of spent automotive catalyst(SAC)and copper-bearing electroplating sludge(CBES),were studied systematically in this paper.The slag structure,melting temperature,and viscous characteristics were investigated by Fourier transform infrared(FTIR)spectroscopy,Raman spectroscopy,Fact Sage calculation,and viscosity measurements.Experimental results show that the increase of Fe_(2)O_(3)content(3.8wt%–16.6wt%),the mass ratio of CaO/SiO_(2)(m(CaO)/m(SiO_(2)),0.5–1.3),and the mass ratio of SiO_(2)/Al_(2)O_(3)(m(SiO_(2))/m(Al_(2)O_(3)),1.0–5.0)can promote the depolymerization of silicate network,and the presence of a large amount of Fe_(2)O_(3)in form of tetrahedral and octahedral units ensures the charge compensation of Al^(3+)ions and makes Al_(2)O_(3)only behave as an acid oxide.Thermodynamic calculation and viscosity measurements show that with the increase of Fe_(2)O_(3)content,m(Ca O)/m(SiO_(2)),and m(SiO_(2))/m(Al_(2)O_(3)),the depolymerization of silicate network structure and low-melting-point phase transformation first occur within the slag,leading to the decrease in melting point and viscosity of the slag,while further increase causes the formation of high-melting-point phase and a resultant re-increase in viscosity and melting point.Based on experimental analysis,the preferred slag composition with low polymerization degree,viscosity,and melting point is as follows:Fe_(2)O_(3)content of 10.2wt%–13.4wt%,m(CaO)/m(SiO_(2))of 0.7–0.9 and m(SiO_(2))/m(Al_(2)O_(3))of 3.0–4.0.This work provides a theoretical support for slag design in co-smelting process of SAC and CBES.
基金supported in part by the 2021 Autonomous Driving Development Innovation Project of the Ministry of Science and ICT,‘Development of Technology for Security and Ultra-High-Speed Integrity of the Next-Generation Internal Net-Work of Autonomous Vehicles’(No.2021-0-01348)and in part by the National Research Foundation of Korea(NRF)grant funded by the Korean Government Ministry of Science and ICT(MSIT)under Grant NRF-2021R1A2C2014428.
文摘Recently,automotive intrusion detection systems(IDSs)have emerged as promising defense approaches to counter attacks on in-vehicle networks(IVNs).However,the effectiveness of IDSs relies heavily on the quality of the datasets used for training and evaluation.Despite the availability of several datasets for automotive IDSs,there has been a lack of comprehensive analysis focusing on assessing these datasets.This paper aims to address the need for dataset assessment in the context of automotive IDSs.It proposes qualitative and quantitative metrics that are independent of specific automotive IDSs,to evaluate the quality of datasets.These metrics take into consideration various aspects such as dataset description,collection environment,and attack complexity.This paper evaluates eight commonly used datasets for automotive IDSs using the proposed metrics.The evaluation reveals biases in the datasets,particularly in terms of limited contexts and lack of diversity.Additionally,it highlights that the attacks in the datasets were mostly injected without considering normal behaviors,which poses challenges for training and evaluating machine learning-based IDSs.This paper emphasizes the importance of addressing the identified limitations in existing datasets to improve the performance and adaptability of automotive IDSs.The proposed metrics can serve as valuable guidelines for researchers and practitioners in selecting and constructing high-quality datasets for automotive security applications.Finally,this paper presents the requirements for high-quality datasets,including the need for representativeness,diversity,and balance.
文摘Free quenching of automotive leaf springs is a new technology that has gradually started to be applied in the industry in China in recent years.Only a few manufacturers are applying it in the industry.Through more than half a year of on-site practice,the changes in the hot forming of spring plates before free quenching have been explored,and finally a heat treatment process that meets the production requirements of our company has been developed,achieving normal production.
文摘In recent years, with attention paid to global environmental problems, there have been requirements for continuous improvement of automobile fuel economy and exhaust gas purification rate. The properties of the ferritic stainless steels (FSS) used to make automobile parts have been improved. This paper introduces the construction of automotive exhaust systems and describes their main failure behaviors and corrosion evaluation procedures.
基金supported by National Natural Science Foundation of China(61502405,61300039)Provincial Science Foundation of Hunan Province(14JJ3130)+1 种基金Fujian Educational Bureau(JA15368)Xiamen University of Technology(YKJ13024R,XYK201437)
文摘Network and software integration pose severe challenges in cyber-security for controller area network(CAN)-based automotive cyber-physical system(ACPS), therefore we employ message authentication code(MAC) to defend CAN against masquerade attack, but the consequent bandwidth overhead makes it a necessity to find the tradeoff among security, real-time and bandwidth utilization for signal packing problem(SPP) of CAN.A mixed-security signal model is firstly proposed to formally describe the properties and requirements on security and real-time for signals, and then a mixed-integer linear programming(MILP)formulation of SPP security-aware signal packing(SASP) is implemented to solve the tradeoff problem, where the bandwidth utilization is improved and the requirements in both security and real-time are met. Experiments based on both society of automotive engineers(SAE) standard signal set and simulated signal set showed the effectiveness of SASP by comparing with the state-of-the-art algorithm.
基金supported partly by the Fundamental Research Funds for Central Universities(No.06500203 and No.00007735).
文摘China is currently vigorously implementing the“energy conservation and emission reduction”and“dual carbon”strategies.As the most resource-advantaged light metal material in China,Magnesium(Mg)alloy is progressively expanding its application in automobile,rail transportation,aerospace,medical,and electronic products.Chongqing University,Shanghai Jiaotong University,and Australian National University have conducted extensive research on the preparation,properties,and processes of Mg alloys.In the past 20 years,the proportion of Mg alloy in the automotive industry has gradually expanded,whereas currently the design and development of Mg alloy parts for automobiles has rarely been reported.Thus,the application models and typical parts cases of Mg alloy are summarized mainly from the four systems of the whole vehicle(body system,chassis system,powertrain system,interior,and exterior system).Subsequently,two actual original equipment manufacturers(OEM)cases are used to introduce the development logic of reliable die-cast Mg alloy,including forward design,formability analysis,process design analysis,structural redesign,manufacturing,and testing,aiming to share the methods,processes,and focus of attention of automotive OEMs for developing Mg alloy parts to enhance the confidence and motivation of applying Mg alloy in automotive field.Eventually,the multiple challenges faced by Mg alloy materials are sorted out and how to face these challenges are discussed.National policies and regulations,environmental protection and energy saving,and consumer demand will continue to promote the application of Mg.
基金the National Science Foundation,the U.S.A.Army Automotive Research Center,the Ford Motor Company,and United Technologies,Inc.
文摘Automobiles evolved from primarily mechanical to electro-mechanical,or mechatronic,vehicles.For example,carburetors have been replaced by fuel injection and air-fuel ratio control,leading to order of magnitude improvements in fuel economy and emissions.Mechatronic systems are pervasive in modem automobiles and represent a synergistic integration of mechanics,electronics and computer science.They are smart systems,whose design is more challenging than the separate design of their mechanical,electronic and computer/control components.In this review paper,two recent methods for the design of mechatronic components are summarized and their applications to problems in automotive control are highlighted.First,the combined design,or co-design,of a smart artifact and its controller is considered.It is shown that the combined design of an artifact and its controller can lead to improved performance compared to sequential design.The coupling between the artifact and controller design problems is quantified,and methods for co-design are presented.The control proxy function method,which provides ease of design as in the sequential approach and approximates the performance of the co-design approach,is highlighted with application to the design of a passive/active automotive suspension.Second,the design for component swapping modularity(CSM)of a distributed controller for a smart product is discussed.CSM is realized by employing distributed controllers residing in networked smart components,with bidirectional communication over the network.Approaches to CSM design are presented,as well as applications of the method to a variable-cam-timing engine,and to enable battery swapping in a plug-in hybrid electric vehicle.
文摘The requirements for automotive lighting systems,especially the light patterns ensuring driver perception,are based on criteria related to the headlamps,rather than the light perceived by drivers and road users.Consequently,important factors such as pavement reflectance,driver age,or time of night,are largely ignored.Other factors such as presence of other vehicles,vehicle speed and weather conditions are considered by the Adaptive Driving Beam(ADB)and Adaptive Front-lighting System(AFS)respectively,though with no information regarding the visual perception of drivers and other road users.Evidently,it is simpler to simulate and measure the light emitted by the lamps than the light reflected by the pavement or emitted by other vehicles.However the current technology in cameras and light sensors,communication protocols,and control of Light Emitting Diodes(LED),combined with decision-making techniques applied to large amounts of data,can open a new era in the operation of headlamps and thus ensure the visual needs of drivers in real time and under actual road conditions.The solution lies in an interaction road-sensor-headlamp,which is not based on the light emitted by headlamps,but rather on the light perceived by the drivers.This study thus proposes a dual grid based on luminance and luminous intensity,which would manage the headlamps by optimizing driver perception and the safety of all road users.
文摘The artificial intelligence is applied to the simulation of the automotive air-conditioning system ( AACS )According to the system's characteristics a model of AACS, based on neural network, is developed. Different control methods of AACS are discussed through simulation based on this model. The result shows that the neural- fuzzy control is the best one compared with the on-off control and conventional fuzzy control method.It can make the compartment's temperature descend rapidly to the designed temperature and the fluctuation is small.
基金Sichuan Province Key Discipline Con-struction for Automotive Engineering ( No.SZD0410 )Research Foundation of Xihua University (No.R0620301)
文摘To evaluate the software behavior of the electronic control unit (ECU) of automotive electrical parking brake (EPB), a software- in-the-loop (SiL) simulation system is built. The EPB is simulated by ARX (auto-regressive with auxiliary input) model, ARMAX (auto-regressive moving average with auxiliary input) model, and NNARMAX (neural network ARMAX) model. By system identification, the ARX(3,4,2), ARX(4,4,2), ARMAX(3,3,1,1), and ARMAX(4,4,3,2) models are derived. Validation results show that the four-order ARMAX model and the NNARMAX model better simulate the actuator of the EPB.
文摘The ability to predict the weathering performance of the clearcoat system over a short period of time is essential for the design and development of coating production. Thus, the primary objective of the present study is to investigate whether it is possible to predict the weathering performance of an automotive paint system through determination of surface roughness, Ra, and micro-hardness before and after various weathering exposure times (0, 24, 168, 336, 504, 672 hours) and when employing two different detergent materials (house-use detergent and car wash detergent). The data were analysed using a pair-sample t-Test, with 0.05 level of significance. It was found that the total net of degradation in the clearcoat level during the first 24 hours was Ra ≈ 30.3 nm (for surface roughness) and 1.358 HV (for the μ-hardness) when using the house-use detergent. In contrast, it was found to be Ra ≈ 4.6 nm (for surface roughness) and 1.133 HV (for μ-hardness) when using the car wash detergent. Also, increased time of weathering (up to 672 hours) increases the Ra and μ-hardness values. It can therefore be concluded that the effect of house-use detergent was more severe than that of car wash detergent on the clearcoat system.
基金supported by the National Key Research and Development Program of China (2018YFB1502502)the National Natural Science Foundation of China (22179127)。
文摘Humidity can affect the attenuation of MEA(membrane electrode assembly), however, the relationship between humidity and MEA decays is complex and ambiguous in realistic application. Herein, we design a simulating automotive protocol, performed on five single fuel cells under RH(relative humidity) 100%,RH 80%, RH 64%, and RH 40%, RH 10%, respectively, to study the relationship of MEA decays and humidity and suggest optimized humidity range to extend the durability. With the electrochemical impedance spectroscopy, cyclic voltammetry, X-ray fluorescence, X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, the four degradation mechanisms about catalyst layer, including Pt dissolution, Pt coarsening, carbon corrosion and ionomer degradation, are observed. Pt coarsening and carbon corrosion are accelerated by higher water content at high humidity. Ionomer degradation and Pt dissolution are enhanced in low humidity. With the linear sweep voltammetry, ion chromatography,nuclear magnetic resonance, tensile test and scan electron microscope, chemical and mechanical degradation in proton exchange membrane are all observed in these five fuels. Chemical degradation, characterized by membrane thinning and more fluoride loss, occurred markedly in RH 10%. Mechanical degradation, characterized by the non-uniformity thickness and bad mechanical properties, is more pronounced in RH 100%, RH 80%, RH 64%. These two degradations are in a moderate level in RH 40%. The research suggests that the RH range from 64% to 40% is conductive to mitigate the degradation of MEAs operated in automotive applications.
基金funded by the National Natural Science Foundation of China (Grant No.52175111)。
文摘In automotive industries,panel acoustic contribution analysis(PACA)is used to investigate the contributions of the body panels to the acoustic pressure at a certain point of interest.Currently,PACA is implementedmostly by either experiment-based methods or traditional numerical methods.However,these schemes are effort-consuming and inefficient in solving engineering problems,thereby restraining the further development of PACA in automotive acoustics.In this work,we propose a PACA scheme using discontinuous isogeometric boundary element method(IGABEM)to build an easily implementable and efficient method to identify the relative acoustic contributions of each automotive body panel.Discontinuous IGABEMis more accurate and converges faster than continuous BEM and IGABEM in the interior sound pressure evaluation of automotive compartments.In this work,a contribution ratio is defined to estimate the relative acoustic contribution of the structure panels;it can be calculated by reusing the coefficient matrix that has already been generated in the sound pressure evaluation process.The utilization of the parallel technique enables the proposed method to be more efficient than conventional methods;it is validated in two numerical examples,including a car passenger compartment subjected to realistic boundary conditions.A sound pressure response experiment based on a steel box is conducted to verify the accuracy of the interior sound pressure calculation using discontinuous IGABEM.This work is expected to promote the practical process of IGABEM for application in automotive acoustic problems.
基金supported by the National Natural Science Foundation of China(62201510,62001091,61801435,61871080,61801435)the Initial Scientific Research Foundation of University of Science and Technology of China(Y030202059018051)+2 种基金Yangtze River Scholar Program,Sichuan Science and Technology Program(2019JDJQ0014)111 Project(B17008)Henan Provincial Department of Science and Technology Research Project(202102210315,212102210029,202102210-137).
文摘This paper considers the non-line-of-sight(NLOS)vehicle localization problem by using millimeter-wave(MMW)automotive radar.Several preliminary attempts for NLOS vehicle detection are carried out and achieve good results.Firstly,an electromagnetic(EM)wave NLOS multipath propagation model for vehicle scene is established.Subsequently,with the help of available multipath echoes,a complete NLOS vehicle localiza-tion algorithm is proposed.Finally,simulation and experimental results validate the effectiveness of the established EM wave propagation model and the proposed NLOS vehicle localization algorithm.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.NRF-2021R1A4A1029650).
文摘Modern vehicles are equipped with multiple Electronic Control Units(ECUs)that support various convenient driving functions,such as the Advanced Driver Assistance System(ADAS).To enable communication between these ECUs,the Controller Area Network(CAN)protocol is widely used.However,since CAN lacks any security technologies,it is vulnerable to cyber attacks.To address this,researchers have conducted studies on machine learning-based intrusion detection systems(IDSs)for CAN.However,most existing IDSs still have non-negligible detection errors.In this paper,we pro-pose a new filtering-based intrusion detection system(FIDS)to minimize the detection errors of machine learning-based IDSs.FIDS uses a whitelist and a blacklist created from CAN datasets.The whitelist stores the cryptographic hash value of normal packet sequences to correct false positives(FP),while the blacklist corrects false negatives(FN)based on transmission intervals and identifiers of CAN packets.We evaluated the performance of the proposed FIDS by implementing a machine learning-based IDS and applying FIDS to it.We conducted the evaluation using two CAN attack datasets provided by the Hacking and Countermeasure Research Lab(HCRL),which confirmed that FIDS can effectively reduce the FP and FN of the existing IDS.
基金Funded by National College Student Innovation and Entrepreneurship Training Program Project(No.CY202036)。
文摘This study explored the synergistic interaction of sewage sludge(SS)and automotive paint sludge(PS)during co-pyrolysis for the optimized treatment of sewage sludge in cement kiln systems,utilizing thermogravimetric analysis(TGA)and thermogravimetric-mass spectrometry(TGA-MS).The result reveals the coexisting synergistic and antagonistic effects in the co-pyrolysis of SS/PS.The synergistic effect arises from hydrogen free radicals in SS and catalytic components in PS,while the main source of the antagonistic effect is that,during the mechanical mixing process,the SS/PS is converted from the particulate form into a dough-like rubbery which contributes to the film-forming effect,hindering the volatilization of volatile components.SS/PS co-pyrolysis reduces the yielding of tar production while increasing coke and gas.This study will provide some in-depth insights into the co-pyrolysis of SS/PS,and offer theoretical support for the subsequent research on the collaborative disposal processes in cement kilns.
文摘本文采用S3C2440A和Windows Automotive 5.0设计了一种汽车导航系统。在硬件方面,给出了S3C2440A和LCD、GPS芯片的接口电路。在软件方面,详细介绍了驱动程序和操作系统的开发方法,并在Visual Studio 2005中成功开发了该系统的GPS信号测试程序。实验结果表明,该系统导航功能良好、可以运行多种导航软件、具有一定的汽车运行状况监控功能。
基金This study was financially supported by the National Natural Science Foundation of China(52072156)the Postdoctoral Foundation of China(2020M682269).
文摘The vehicle industry is always in search of breakthrough energy-saving and emission-reduction technologies.In recent years,vehicle intelligence has progressed considerably,and researchers are currently trying to take advantage of these developments.Here we consider the case of many vehicles forming a queue,i.e.,vehicles traveling at a predetermined speed and distance apart.While the majority of existing studies on this subject have focused on the influence of the longitudinal vehicle spacing,vehicle speed,and the number of vehicles on aerodynamic drag and fuel economy,this study considers the lateral offset distance of the vehicle queue.The group fuel consumption savings rate is calculated and analyzed.As also demonstrated by experimental results,some aerodynamic benefits exist.Moreover,the fuel consumption saving rate of the vehicle queue decreases as the lateral offset distance increases.
文摘Instant noodles contain 16 to18 percent fat,including 11 percent from palm oil.Most people have no idea where palm oil comes from or what it is used for,but they could not live without it because it is so widely used in personal hygiene products such as shampoo,tooth paste,facial cream,and soap.It is also an ingredient in automotive lubricants and food such as fried chicken,chocolate,and various pastries.