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Approximate Optimal Filter Design for Vehicle System through Actor‑Critic Reinforcement Learning

Automotive Innovation 2022年第4期5卷 415-426页

作者： Yuming Yin Shengbo Eben Li Kaiming Tang Wenhan Cao Wei Wu Hongbo Li School of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China Beijing Geekplus Tech.Co. LtdBeijingChina

Precise state and parameter estimations are essential for identification,analysis and control of vehicle engineering problems,especially under significant model and measurement uncertainties.The widely used filtering/estimation algorithms,such as Kalman series like Kalman filter,extended Kalman filter,unscented Kalman filter,and particle filter,generally aim to approach the true state/parameter distribution via iteratively updating the filter gain at each time step.However,the optimal-ity of these filters would be deteriorated by unrealistic initial condition or significant model error.Alternatively,this paper proposes to approximate the optimal filter gain by considering the effect factors within infinite time horizon,on the basis of estimation-control duality.The proposed approximate optimal filter(AOF)problem is designed and subsequently solved by actor-critic reinforcement learning(RL)method.The AOF design transforms the traditional optimal filtering problem with the minimum expected mean square error into an optimal control problem with the minimum accumulated estimation error,in which the estimation error is used as the surrogate system state and the infinite-horizon filter gain is the control input.The estimation-control duality is proved to hold when certain conditions about initial vehicle state distributions and policy structure are maintained.In order to evaluate of the effectiveness of AOF,a vehicle state estimation problem is then demonstrated and compared with the steady-state Kalman filter.The results showed that the obtained filter policy via RL with different discount factors can converge to theoretical optimal gain with an error within 5%,and the average estimation errors of vehicle slip angle and yaw rate are less than 1.5×10–4.

关键词： Vehicle state estimation Kalman filter Estimation-control duality Reinforcement learning

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宋、金、蒙政局变动下的华北武装团体政治抉择研究:以红袄军杨妙真、李璮集团为例

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中国史研究 2023年第1期 134-151页

作者：曹文瀚四川师范大学历史文化与旅游学院

金朝末年,华北政治秩序瓦解,民众为求自保,组成大大小小的武装团体,他们的政治向背对当时宋、金、蒙三方逐鹿中原的成果有莫大的影响力。红袄军是这些武装团体中最反复无常者,研究他们政治抉择的因素,可以增进我们对当时武装团体政治向... 详细信息

金朝末年,华北政治秩序瓦解,民众为求自保,组成大大小小的武装团体,他们的政治向背对当时宋、金、蒙三方逐鹿中原的成果有莫大的影响力。红袄军是这些武装团体中最反复无常者,研究他们政治抉择的因素,可以增进我们对当时武装团体政治向背的认识。杨妙真和李璮是红袄军第三代及第四代首领,李璮起事对元代以至后世历史皆产生深远的影响。除此之外他们集团内部还有无数的各级领导人,大致上可分成山东和涟海两大集团,后者受限于史料,生平事迹多不得而知;前者则能利用地方志史料,大量恢复他们的生平事迹,由此得知李璮集团的组成结构及其对李璮政治抉择的影响。李璮失败后,元朝将罪责限定在李璮、王文统及涟海集团,以此争取山东集团的认同,进而稳定对山东的统治。

关键词：红袄军杨妙真李璮山东

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Real-world emission characteristics of carbonyl compounds from agricultural machines based on a portable emission measurement system

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Journal of Environmental Sciences 2023年第2期124卷 846-859页

作者： wenhan Yu Xianbao Shen BoboWu Lei Kong Kaijie Xuan Cheng Zhao Xinyue cao Xuewei Hao Xin Li Hanyu Zhang Zhiliang Yao School of Ecology and Environment Beijing Technology and Business UniversityBeijing 100048China State Environmental Protection Key Laboratory of Food Chain Pollution Control Beijing Technology and Business UniversityBeijing 100048China Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry Beijing Technology and Business UniversityBeijing 100048China

Emissions of carbonyl compounds from agricultural machines cannot be ignored.Carbonyl compounds can cause the formation of ozone(O3)and secondary organic aerosols,which can cause photochemical smog to form.In this study,20 agricultural machines were tested using portable emission measurement system(PEMS)under real-world tillage processes.The exhaust gases were sampled using 2,4-dinitrophenylhydrazine cartridges,and 15 carbonyl compounds were analyzed by high-performance liquid chromatography.Carbonyl compound emission factors for agricultural machines were 51.14–3315.62 mg/(kg-fuel),and were 2.58±2.05,0.86±1.07 and 0.29±0.20 g/(kg-fuel)for China 0,China II and China III emission standards,respectively.Carbonyl compound emission factor for sowing seeds of China 0 agricultural machines was 3.32±1.73 g/(kg-fuel).Formaldehyde,acetaldehyde and acrolein were the dominant carbonyl compounds emitted.Differences in emission standards and tillage processes impact ozone formation potential(OFP).The mean OFP was 20.15±16.15 g O3/(kg-fuel)for the China 0 emission standard.The OFP values decreased by 66.9% from China 0 to China II,and 67.4%from China II to China III.The mean OFP for sowing seeds of China 0 agricultural machines was 25.92±13.84 g O3/(kg-fuel).Between 1.75 and 24.22 times more ozone was found to be formed during sowing seeds than during other processes for China 0 and China II agricultural machines.Total carbonyl compound emissions from agricultural machines in China was 19.23 Gg in 2019.The results improve our understanding of carbonyl compound emissions from agricultural machines in China.

关键词： Agricultural machines Carbonyl compounds Emission characteristics Tillage process PEMS

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Tribological Behaviours of PTFE Composites Filled with PEEK and Nano-ZrO2 Based on Pin-on-Flat Reciprocating Friction Model

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 87-98页

作者：祁渊龚俊 cao wenhan 王宏刚 Mechanical and Electrical Engineering College Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Nano-ZrO2 and PEEK particles were synergistically filled in unfilled PTFE to improve the wear resistance and maintain a relatively low friction coefficient,and the materials were studied using a reciprocating sliding friction and wear tester.In the friction tests,the evolution of various tribological characteristics in both the contact interfaces and debris was observed,and the wear mechanism of the PTFE composites was investigated.The results showed that the wear rate of the PTFE composites synergistically filled with nano-ZrO2 and PEEK was lower and its friction coefficient was slightly higher than that of the unfilled PTFE;the uniformity and continuity of the transfer film generated by the composite with nano-ZrO2 and PEEK were the best,and the particle size of the debris was minimal in comparison to that in other sample systems.

关键词： PTFE nano-ZrO2 tribology transfer film

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GOPS:A general optimal control problem solver for autonomous driving and industrial control applications

Communications in Transportation Research

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Communications in Transportation Research 2023年第1期3卷 92-106页

作者： Wenxuan Wang Yuhang Zhang Jiaxin Gao Yuxuan Jiang Yujie Yang Zhilong Zheng Wenjun Zou Jie Li Congsheng Zhang Wenhan Cao Genjin Xie Jingliang Duan Shengbo Eben Li School of Vehicle and Mobility Tsinghua UniversityBeijing100084China

Solving optimal control problems serves as the basic demand of industrial control tasks.Existing methods like model predictive control often suffer from heavy online computational burdens.Reinforcement learning has shown promise in computer and board games but has yet to be widely adopted in industrial applications due to a lack of accessible,high-accuracy solvers.Current Reinforcement learning(RL)solvers are often developed for academic research and require a significant amount of theoretical knowledge and programming skills.Besides,many of them only support Python-based environments and limit to model-free algorithms.To address this gap,this paper develops General Optimal control Problems Solver(GOPS),an easy-to-use RL solver package that aims to build real-time and high-performance controllers in industrial fields.GOPS is built with a highly modular structure that retains a flexible framework for secondary development.Considering the diversity of industrial control tasks,GOPS also includes a conversion tool that allows for the use of Matlab/Simulink to support environment construction,controller design,and performance validation.To handle large-scale problems,GOPS can automatically create various serial and parallel trainers by flexibly combining embedded buffers and samplers.It offers a variety of common approximate functions for policy and value functions,including polynomial,multilayer perceptron,convolutional neural network,etc.Additionally,constrained and robust algorithms for special industrial control systems with state constraints and model uncertainties are also integrated into GOPS.Several examples,including linear quadratic control,inverted double pendulum,vehicle tracking,humanoid robot,obstacle avoidance,and active suspension control,are tested to verify the performances of GOPS.

关键词： Industrial control Reinforcement learning Approximate dynamic programming Optimal control Neural network Benchmark

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“大西”考:兼议《元典章》的“大西”

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元史及民族与边疆研究集刊 2021年第1期 220-234页

作者：曹文瀚四川师范大学历史文化与旅游学院

《元典章》收录了元代大量的原始官方文书,是研究蒙元史的重要宝库。但由于书中充斥案牍之文、方言俗语、蒙文直译体,因此校勘、点校、解读《元典章》一直是蒙元史研究者的一大任务。《元典章·色目汉儿相参勾当》有一“大西札发儿”,... 详细信息

《元典章》收录了元代大量的原始官方文书,是研究蒙元史的重要宝库。但由于书中充斥案牍之文、方言俗语、蒙文直译体,因此校勘、点校、解读《元典章》一直是蒙元史研究者的一大任务。《元典章·色目汉儿相参勾当》有一“大西札发儿”,洪金富先生原以此“大西”可能有“大西”及“大哥”二说。前者为“广大的西域”,后者指契丹人石抹咸得不。而后又认为大西可能是指“遥远的西方”。经查“中国基本古籍库”,搜出了3251条“大西”,整理后约可分成43类,其中出现在明代以前的“大西”共有十类,在这之中,又以“偏西或极西”,也就是“遥远的西方”是最早出现的“大西”使用方式。故此用法应当就是“大西札发儿”的“大西”之意。

关键词：大西元典章中国基本古籍库

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民国《临沂县志》收录的两块元碑年代考——兼论金元之际的山东沂州

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元史及民族与边疆研究集刊 2020年第2期 46-58页

作者：曹文瀚四川师范大学历史文化与旅游学院

沂州位处山东南端,唐朝以后长期以临沂为治所。沂州在金元之际的历史因史籍阙载而不甚清晰,民国《临沂县志》收录了两块元代碑刻,通过对碑文的考释可以补史传之失。这两块碑文撰刻的时间分别为1234年及1247年,透过对碑文的解读并参照金... 详细信息

沂州位处山东南端,唐朝以后长期以临沂为治所。沂州在金元之际的历史因史籍阙载而不甚清晰,民国《临沂县志》收录了两块元代碑刻,通过对碑文的考释可以补史传之失。这两块碑文撰刻的时间分别为1234年及1247年,透过对碑文的解读并参照金元之际的历史事实,可以确定金元之际的沂州在1222年后为李全控制,李全投降蒙古后不久,屯驻于沂、邳、滕交界处的胡义与密珍也加入红袄军,且颇受红袄军李氏集团的重视,李璮与之结为姻亲,并由胡义治理沂州。金元之际的沂州在胡义治理下经济复苏、社会秩序稳定,并建立官府与州学。这对于研究金元之际山东地方社会治理的状况,有所推进。

关键词：临沂沂州红袄军李全胡义

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北宋曹洞宗禅僧安庆行化考

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安庆师范大学学报（社会科学版） 2023年第6期42卷 30-36页

作者：黄文翰安庆师范大学人文学院安徽安庆246011

北宋中兴曹洞宗的三位关键人物法远(991—1067)、义青(1032—1083)、道楷(1043—1118)皆与安庆结缘甚深。法远于桐城浮山付法义青,化解了曹洞正脉行将失坠的危机;义青先于浮山潜修悟道,后长期弘法太湖白云山、桐城投子山,拉开了曹洞宗... 详细信息

北宋中兴曹洞宗的三位关键人物法远(991—1067)、义青(1032—1083)、道楷(1043—1118)皆与安庆结缘甚深。法远于桐城浮山付法义青,化解了曹洞正脉行将失坠的危机;义青先于浮山潜修悟道,后长期弘法太湖白云山、桐城投子山,拉开了曹洞宗中兴的序幕。道楷开悟于白云山,后于汴京丕振洞下宗风,曹洞宗中兴局面至此大成。要之,安庆是北宋曹洞宗中兴当之无愧的肇始之地。

关键词：北宋曹洞宗安庆法远义青道楷

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特高压高端阀厅防屈曲支撑结构地震响应分析

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南方电网技术 2020年第9期14卷 17-23页

作者：曹枚根徐文汉娄杨剑北方工业大学北京100144 浙江省电力建设有限公司杭州310007

阀厅作为换流站最为重要的建筑物。有必要采取有效的减震技术控制高烈度地区阀厅的地震响应。首先介绍了防屈曲支撑的构成和耗能机理,提出了防屈曲支撑在高烈度地区的阀厅结构中耗能减震方案。然后,对比分析了阀厅结构在9度多遇和9度罕... 详细信息

阀厅作为换流站最为重要的建筑物。有必要采取有效的减震技术控制高烈度地区阀厅的地震响应。首先介绍了防屈曲支撑的构成和耗能机理,提出了防屈曲支撑在高烈度地区的阀厅结构中耗能减震方案。然后,对比分析了阀厅结构在9度多遇和9度罕遇地震下的不同耗能减震方案的减震效果。结果显示:采用了防屈曲支撑的阀厅结构其振型和基本频率没有发生太大的变化;在多遇地震下,各个方案下的阀厅结构的地震响应比较接近,防屈曲支撑没有屈服,相当于普通钢支撑,起到提供侧向刚度作用;在罕遇地震下,采用了防屈曲支撑的阀厅结构大大降低了其地震响应,防屈曲支撑的耗能减震效果良好。

关键词：特高压换流站高端阀厅防屈曲支撑(BRB) 减震技术地震响应

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Seismic attenuation compensation with spectral-shaping regularization

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Earth and Planetary Physics 2022年第3期6卷 259-274页

作者： QiZhen Du WanYu Wang wenhan Sun Li-Yun Fu Shandong Provincial Key Laboratory of Deep Oil&Gas China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Key Laboratory of Geophysical Prospecting China National Petroleum Corporation(CNPC)China University of Petroleum(East China)Qingdao 266580China Department of Physics University of AlbertaEdmontonABT6G 2EICanada

Because of the viscoelasticity of the subsurface medium,seismic waves will inherently attenuate during propagation,which lowers the resolution of the acquired seismic records.Inverse-Q filtering,as a typical approach to compensating for seismic attenuation,can efficiently recover high-resolution seismic data from attenuation.Whereas most efforts are focused on compensating for highfrequency energy and improving the stability of amplitude compensation by inverse-Q filtering,low-frequency leakage may occur as the high-frequency component is boosted.In this article,we propose a compensation scheme that promotes the preservation of lowfrequency energy in the seismic data.We constructed an adaptive shaping operator based on spectral-shaping regularization by tailoring the frequency spectra of the seismic data.We then performed inverse-Q filtering in an inversion scheme.This data-driven shaping operator can regularize and balance the spectral-energy distribution for the compensated records and can maintain the low-frequency ratio by constraining the overcompensation for high-frequency energy.Synthetic tests and applications on prestack common-reflectionpoint gathers indicated that the proposed method can preserve the relative energy of low-frequency components while fulfilling stable high-frequency compensation.

关键词： seismic attenuation compensation spectral-shaping regularization data-driven shaping operator offset-related inverse-Q filter

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