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Eco-Driving Optimization Method for Heterogeneous CAVs at an Isolated Unsignalized Intersection

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Eco-Driving Optimization Method for Heterogeneous CAVs at an...

IEEE International Conference on Unmanned Systems (ICUS)

作者： Jianjun Cai Yonggang Liu Wenwei Que Yuanjian Zhang Zheng Chen State Key Laboratory of Mechanical Transmissions Chongqing University Chongqing China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha China Department of Aeronautical and Automotive Engineering Loughborough University Loughborough United Kingdom Faculty of Transportation Engineering Kunming University of Science and Technology Kunming China

This paper presents an eco-driving optimization method for heterogeneous connected autonomous vehicles (CAVs) of mixed electric vehicles (EVs) and traditional fuel vehicles (FVs) at an isolated unsignalized intersection. An optimization method is designed to compute the arrival time of each vehicle in the heterogeneous vehicle fleet. Furthermore, we use quadratic programming to optimize the speed trajectory for EVs and the Gauss Pseudospectral method for FVs. Then, an eco-driving optimization method based on a rolling optimization framework that combines the time schedule algorithm and trajectory optimization method is proposed. We make a comparative study with the dynamic programming algorithm and simulation results show that our method outperforms the baselines, where the average energy consumption of EVs and FVs has been reduced by 0.09% and 0.14%, respectively.

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Theoretical Study on the Competitive Mechanism of Alloying Elements in L12-(Ni X 1cr X 2co X 3)3al Precipitates

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SSRN 2023年

作者： Liu, Yu Zhao, Juan-Gang Wang, Zhi-Peng Fan, Tou-Wen Wu, Yuan-Zhi Zhang, Rui-Zhi Zhou, Xiang-Jun Zhou, Jie Tang, Ping-Ying Research Institute of Automobile Parts Technology Hunan Institute of Technology Hengyang421002 China College of Materials Science and Engineering Hunan University Changsha410082 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China Key Laboratory of New Electric Functional Materials of Guangxi Colleges and Universities Nanning Normal University Guangxi Province Nanning530023 China School of Materials Science and Engineering

The impact of variations in the content of single alloying element on the properties of alloy materials has been extensively discussed, but the influence of this change on the content of multiple alloying elements in the alloy materials has been disregarded, as the performances of alloy materials should be determined by the collective influence of multiple alloying elements. To address the aforementioned issue, the present study conducts a comprehensive investigation into the impact of variations in the content of alloying elements, namely Ni, Cr, and Co, on the structural and mechanical properties of L12-(Nix1Crx2Cox3)3Al precipitates using the high-throughput first-principles calculations and the partial least squares (PLS) regression, and the competitive mechanism among these three elements is elucidated. In the analysis of the change in the content of a single alloy element, we can observe that the value of elastic constant gradually increases with the increase of Ni content. However, subsequent PLS regression analysis conducted on the three alloy elements revealed a significant negative overall competitive effect of the Ni element, indicating that the results of analyzing single alloying element may be completely opposite to those of analyzing multiple alloying elements. This phenomenon is also observed in the analysis of Vickers hardness and yield strength of L12 precipitates with the addition of Cr element, which will not be conducive to further experimental preparation. Therefore, the methodology proposed in this study will facilitate the elucidation of competition mechanisms among different alloy elements and offer a more robust guidance for experimental preparation. © 2023, The Authors. All rights reserved.

关键词： Alloying elements

The progress in the verification of key technologies for floating structures near islands and reefs

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Journal of Hydrodynamics 2021年第1期33卷 1-12页

作者： You-sheng Wu Jun Ding Xue-kang Gu Chun-yan Ji Xiong-bo Zheng Guo-ping Zhou Dao-lin Xu Li Ma China Ship Scientific Research Center Wuxi 214082China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China Shanghai Merchant Ship Design and Research Institute Shanghai 201203China College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteQingdao 266000China

In 2019 a Scientific Research&Demonstration Platform was deployed near islands and reefs in South China Sea by a joint research group of 7 institutes and universities in *** is a simplified small model of a two-module semi-submersible-type *** test on site has continued for more than one and half years since then for long-term observations to validate the developed key technologies for design and behavior predictions of floating structures deployed near islands and *** integrated information system was set up to continuously collect and inspect the data of the encountered waves,structure responses,connector forces,mooring line forces,anti-corrosion status of the platform,the performance efficiencies of a floating breakwater nearby and a wave energy converter attached on the *** this paper,the status of the on-site measurements and validations of the key technologies are briefly described.

关键词： near islands and reefs inhomogeneous wave environment multi-module floating structures VLFS floating breakwater wave responses hydroelastic analysis predictions on-site measurements validation verification

Application of Johnson-Cook Model in Failure Simulation for Steel-Aluminium Hybrid Spr Joint Under Dynamic Loading

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SSRN 2022年

作者： Duan, Libin Xue, Kaiwen Du, Zhanpeng Ma, Hongfeng Li, Wen Su, Yulong Institute of Lightweight and Safety of New Energy Vehicle School of Automotive and Traffic Engineering Jiangsu University Zhenjiang212013 China Jiangsu XCMG State Key Laboratory Technology Co. Ltd. Xuzhou221001 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China

Steel-aluminium hybrid material is the main development direction of body material combination. This paper aims to investigate the failure behaviour of high-strength steel B280VK and aluminum alloy 6063-T6. First, the parameters of Johnson-Cook (J-C) material model (i.e. J-C constitutive and failure model) are experimentally obtained by conducted uniaxial and notch tensile tests at five constant loading speeds of 3mm/min, 1.25 m/s, 2.5 m/s and 7.5 m/s. Then, numerical simulation of different tensile tests on B280VK and 6063-T6 specimens has been done in commercial software LS-DYNA using J-C material model. The results reveal that the established J-C material model can accurately simulate the mechanical performance and failure behaviour of high-strength steel B280VK and aluminum alloy 6063-T6. Finally, the J-C material model is used to simulate the failure behaviour of self-piercing riveting (SPR) joint with steel-aluminium hybrid material under dynamic loading. By comparing the numerical results with those of the experiment results, it can be found that the established J-C material model can describe the deformation and failure behaviour of steel-aluminium hybrid SPR joint well. © 2022, The Authors. All rights reserved.

关键词： Tensile testing

Time-Domain Transfer Path Analysis Based on Gaussian Process Latent Force Model and Least Squares

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SSRN 2024年

作者： Zhu, Yu He, Zhicheng Zhou, Enlin L. Li, Eric Chen, Y.J. Gao, H. State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Hunan University Changsha410082 China School of Computing Engineering & Digital Technologies Teesside University Middlesbrough United Kingdom Chinese Scholartree Ridge Laboratory China North Vehicle Research Institute Beijing100072 China Liuzhou Wuling New Energy Vehicle Co. Ltd. Guangxi Automobile Group Co. Ltd. Liuzhou545005 China

The appearance of Time-domain transfer path analysis (TPA) has provided an effective means for addressing the issues of noise, vibration, and harshness (NVH) in mechanical systems under transient conditions. However, two primary challenges exist with this approach. Firstly, computing the generalized inverse of the frequency response functions (FRFs) matrix from excitations to indicators is prone to numerical instabilities, leading to ill-conditioned problems. Secondly, the accuracy of time-domain information extracted from existing frequency-domain data is relatively low. These issues diminish the precision of classical time-domain TPA methods in time-domain loads identification and impulse response functions (IRFs) recognition, thereby affecting their accuracy. In this work, we propose a novel time-domain TPA method that integrates the gaussian process latent force model (GPLFM) with the least squares (LS). Initially, this method explores the GPLFM in fluid-structure interaction (FSI) system. Secondly, a genetic algorithm (GA) is utilized to determine optimal parameters of the indicators. Subsequently, the vibration IRFs are identified using the LS. Finally, the contribution of each path to the targets' vibration is calculated using linear convolution, while a Kalman filter without measurement updates predicts the noise contribution. Case studies have demonstrated that the proposed method achieved higher accuracy in time-domain loads identification under multiple loading conditions compared to traditional methods using deconvolution filters. Additionally, the accuracy of calculating the contributions surpasses that of traditional methods employing linear convolution. © 2024, The Authors. All rights reserved.

关键词： Genetic algorithms

A Novel Multi-Stage Concurrent Topology Optimization For Variable-Stiffness Structures

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SSRN 2024年

作者： Zhang, Yaya Wang, Hu Yin, Jichao Li, Shuhao Yang, Mengzhu State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China Beijing Institute of Technology Shenzhen Automotive Research Institute Shenzhen518000 China Department of Aerospace Engineering University of Bristol BS8 1TR United Kingdom

The concurrent optimization of topology and fibre orientation is a promising approach to pursue higher strength and lighter weight of variable-stiffness structures. This paper suggests a novel discrete-continuous scheme for the concurrent optimization. Considering the global convergence, Discrete Material Optimization is firstly utilized to select a dominant angle for each element from several predefined candidate angles. However, some regions with multiaxial stress make it difficult to select the definite angles for the elements. Therefore, the Sequential Binary-Phase Topology Optimization is suggested to guarantee the uniqueness of the element to candidate angle mapping. Moreover, to obtain better mechanical properties, Continuous Fibre Angle Optimization with spatial filter is introduced to optimize fibre continuity. Several classic numerical examples are used to verify the excellent performance of the suggested method in terms of fibre angle convergence and show the robustness regarding sensitivity to the initial setting. © 2024, The Authors. All rights reserved.

关键词： Shape optimization

Probing the Effect of Static Thermal Aging and Ultraviolet Aging on Performance Characteristic of Lithium Complex Grease and Polyurea Grease

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SSRN 2023年

作者： Ren, Guanlin Zhou, Changjiang Fan, Xiaoqiang Liu, Yahui State Key Laboratory of Advanced Design and Manufacture for Vehicle Body Hunan University Changsha410082 China Southwest Jiaotong University Chengdu610031 China Beijing Engineering Research Center of Precision Measurement Technology and Instruments Beijing University of Technology Beijing100124 China

Space equipment inevitablely suffers from ultraviolet (UV) irradiation and thermal aging, which results in the structure/composition change and properties decrease. In this study, the lithium complex grease (LCG) and polyurea grease (PUG) were prepared with three different concentrations (20%, 15%, 10%), and the effect of static thermal (ST) aging and UV aging on physicochemical, rheological and tribological properties was investigated in detail. Results shows that the PUG (20%) exhibited the greatest physicochemical properties as a result of the high tenacity spiral polyurea fiber's strong interaction with PAO40. UV and ST aging resulted in the oxidation of base oil and physical/chemical degradation of thickener, thereby decreased the dropping point and oil separation, as well as the changes of thixotropy. And ST aging led to higher oil-bleeding rate than UV aging, due to a higher degree of degradation for ST aging. The fresh LCG containing 10% thickener demonstrated the greatest tribological properties due to the synergistic action of tribo-chemical film and oil film. The tribological proeprties of LCG after ST aging was improved because the ST aging improved the flowbility. © 2023, The Authors. All rights reserved.

关键词： Thermal aging

Janus-graphene: a two-dimensional half-auxetic carbon allotropes with non-chemical Janus configuration

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arXiv

arXiv 2023年

作者： Yu, Linfeng Xu, Jianhua Shen, Chen Zhang, Hongbin Zheng, Xiong Wang, Huiming Qin, Zhenzhen Qin, Guangzhao National Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle College of Mechanical and Vehicle Engineering Hunan University Changsha410082 China Institute of Materials Science Technical University of Darmstadt Darmstadt64287 Germany Hunan Key Laboratory for Micro-Nano Energy Materials & Device School of Physics and Optoelectronics Xiangtan University Hunan Xiangtan411105 China School of Physics and Microelectronics Zhengzhou University Zhengzhou450001 China Greater Bay Area Institute for Innovation Hunan University Guangdong Province Guangzhou511300 China

The asymmetric properties of Janus two-dimensional materials commonly depend on chemical effects, such as different atoms, elements, material types, etc. Herein, based on carbon gene recombination strategy, we identify an intrinsic non-chemical Janus configuration in a novel purely sp2 hybridized carbon monolayer, named as Janus-graphene. With the carbon gene of tetragonal, hexagonal, and octagonal rings, the spontaneous unilateral growth of carbon atoms drives the non-chemical Janus configuration in Janus-graphene, which is totally different from the chemical effect in common Janus materials such as MoSSe. A structure-independent half-auxetic behavior is mapped in Janus-graphene that the structure maintains expansion whether stretched or compressed, which lies in the key role of pz orbital. The unprecedented half-auxeticity in Janus-graphene extends intrinsic auxeticity into pure sp2 hybrid carbon configurations. With the unique half-auxeticity emerged in the non-chemical Janus configuration, Janus-graphene enriches the functional carbon family as a promising candidate for micro/nanoelectronic device applications. Copyright © 2023, The Authors. All rights reserved.

关键词： Graphene

A study on generalized optimization of energy distribution in electric vehicle hybrid energy storage system for personalized driving style scores

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Energy Conversion and Management 2025年 341卷

作者： Lin Hu Qingtao Tian Jing Huang Dongjie Zhang Xianhui Wu Xiaojian Yi College of Mechanical and Vehicle Engineering Changsha University of Science and Technology Changsha 410114 China Hunan Province Key Laboratory of Safety Design and Reliability Technology for Engineering Vehicle Changsha University of Science and Technology Changsha 410114 China College of Transportation Engineering Changsha University of Science and Technology Changsha 410114 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha 410082 China Key Laboratory of Traffic Safety on Track of Ministry of Education School of Traffic and Transportation Engineering Central South University Changsha 410000 China

Balancing battery capacity degradation and system energy loss while optimizing supercapacitor utilization remains a key challenge in hybrid energy storage system (HESS) for electric vehicle (EV). This study proposes a generalized optimization strategy based on personalized driving style scores. Using real-world EV data, Lasso regression identifies key energy consumption parameters for energy distribution control. Principal component analysis (PCA) and K-means clustering are then applied to classify the sample conditions into three driving styles: cautious, standard, and aggressive. The comprehensive scores for sample conditions are normalized to obtain individualized driving style scores, which serve as core indicators of personalized driving characteristics. A significant linear correlation is observed between the driving style scores and both battery capacity degradation and system energy loss. Based on this, a piecewise linear fitting model is constructed to calculate the contributions of battery capacity degradation and system energy loss to the total operational loss for each sample condition. These contributions are mapped to range of optimization weights, generating personalized weights for battery capacity degradation and system energy loss. A generalized weighted optimization cost function is then formulated, which is compatible with various optimization algorithms. Using GWO as an example, the results demonstrate that the proposed weighted optimization strategy reduces the average battery capacity degradation for aggressive driving styles by an additional 8.43% and decreases the average system energy loss for cautious driving styles by an additional 5.09% compared to non-weighted optimization. This enhances the flexibility and applicability of energy distribution in HESS.

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