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General Optimal Trajectory Planning: Enabling Autonomous Vehicles with the Principle of Least Action

Heye Huang,Yicong Liu,Jinxin Liu,Qisong Yang,Jianqiang Wang,David Abbink,Arkady Zgonnikov,

《工程(英文)》 doi: 10.1016/j.eng.2023.10.001

摘要: This study presents a general optimal trajectory planning (GOTP) framework for autonomous vehicles (AVs) that can effectively avoid obstacles and guide AVs to complete driving tasks safely and efficiently. Firstly, we employ the fifth-order Bezier curve to generate and smooth the reference path along the road centerline. Cartesian coordinates are then transformed to achieve the curvature continuity of the generated curve. Considering the road constraints and vehicle dynamics, limited polynomial candidate trajectories are generated and smoothed in a curvilinear coordinate system. Furthermore, in selecting the optimal trajectory, we develop a unified and auto-tune objective function based on the principle of least action by employing AVs to simulate drivers’ behavior and summarizing their manipulation characteristics of “seeking benefits and avoiding losses.” Finally, by integrating the idea of receding-horizon optimization, the proposed framework is achieved by considering dynamic multi-performance objectives and selecting trajectories that satisfy feasibility, optimality, and adaptability. Extensive simulations and experiments are performed, and the results demonstrate the framework’s feasibility and effectiveness, which avoids both dynamic and static obstacles and applies to various scenarios with multi-source interactive traffic participants. Moreover, we prove that the proposed method can guarantee real-time planning and safety requirements compared to drivers’ manipulation.

关键词: Autonomous vehicle     Trajectory planning     Multi-performance objectives     Principle of least action    

迈向L5级自动驾驶汽车的发展原则 Article

王建强, 黄荷叶, 李克强, 李骏

《工程(英文)》 2021年 第7卷 第9期   页码 1313-1325 doi: 10.1016/j.eng.2020.10.018

摘要:

自动驾驶汽车的快速发展给现有交通出行方式带来了全新面貌和潜在挑战。目前,L3 级及以下驾驶辅助系统已经量产,L4 级在特定场景下的一些应用也逐步开发,通过逐渐提高车辆的自动化、智能化程度来不断向完全自动驾驶发展。然而,针对L5 级自动驾驶汽车的发展思路始终未明确,而现有针对L0~L4级自动驾驶发展过程的研发方式主要基于任务驱动来进行特定场景下的功能开发,难以揭示高等级自动驾驶汽车所需解决问题的本质逻辑和物理机制,进而阻碍了迈向L5 级自动驾驶的途径。本文通过探索高等级自动驾驶系统背后的物理机制,并从驾驶的本质出发,采用推理演绎方式,提出“大脑-小脑-器官”协调平衡框架,基于“乌鸦推理+鹦鹉学舌”的混合模式,探索“自主学习+先验知识”的研究范式,实现自动驾驶汽车“自学习、自适应、自超越”特性。从系统、统一、均衡的角度出发,基于最小作用量原理和统一安全场思想,旨在为高等级自动驾驶汽车,尤其是L5 级自动驾驶的研发提供一种全新的研发思路与有效途径。

关键词: 自动驾驶汽车     最小作用量原理     行车安全场     自主学习     基础范式    

Theory and method of mechanism system design

Huijun ZOU, Qinghua LIANG, Qing ZHANG

《机械工程前沿(英文)》 2010年 第5卷 第4期   页码 399-411 doi: 10.1007/s11465-010-0116-8

摘要: Conceptual design is the most critical and creative phase of design. Recently, increasing attention has been directed to supporting conceptual-level computer aided creative design and its theories and methodologies. Specifically, for conceptual design of mechanical products, this paper presents a novel function solving model for mechanical product design and highlights the importance of systematic synthesis to achieve creative design. Then it builds a framework as a function-effect-process-action- mechanisms (FEPAM) mapping process, which enables creative design on the basis of conceiving different action schemes. After that, several key points are elaborated including 1) representing and decomposition methods of functions and motion behaviors; 2) action scheme representing method based on network plan techniques; and 3) variation and creation methods based on action scheme transformations.

关键词: mechanism system creative design     process model     function solving model     process action procedure     mechanisms knowledge base     principle of mechanism system composition    

View-invariant human action recognition via robust locally adaptive multi-view learning

Jia-geng FENG,Jun XIAO

《信息与电子工程前沿(英文)》 2015年 第16卷 第11期   页码 917-920 doi: 10.1631/FITEE.1500080

摘要: Human action recognition is currently one of the most active research areas in computer vision. It has been widely used in many applications, such as intelligent surveillance, perceptual interface, and content-based video retrieval. However, some extrinsic factors are barriers for the development of action recognition; e.g., human actions may be observed from arbitrary camera viewpoints in realistic scene. Thus, view-invariant analysis becomes important for action recognition algorithms, and a number of researchers have paid much attention to this issue. In this paper, we present a multi-view learning approach to recognize human actions from different views. As most existing multi-view learning algorithms often suffer from the problem of lacking data adaptiveness in the nearest neighborhood graph construction procedure, a robust locally adaptive multi-view learning algorithm based on learning multiple local L1-graphs is proposed. Moreover, an efficient iterative optimization method is proposed to solve the proposed objective function. Experiments on three public view-invariant action recognition datasets, i.e., ViHASi, IXMAS, and WVU, demonstrate data adaptiveness, effectiveness, and efficiency of our algorithm. More importantly, when the feature dimension is correctly selected (i.e.,>60), the proposed algorithm stably outperforms state-of-the-art counterparts and obtains about 6% improvement in recognition accuracy on the three datasets.

关键词: View-invariant     Action recognition     Multi-view learning     L1-norm     Local learning    

China released the Action Plan on Prevention and Control of Soil Pollution

Fang Zhang,Guanghe Li

《环境科学与工程前沿(英文)》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0867-5

Function and principle innovative design of mechanical products based on TRIZ/FA

YUAN Feng, WANG Tai-yong, NIE Hui-juan

《机械工程前沿(英文)》 2006年 第1卷 第3期   页码 350-355 doi: 10.1007/s11465-006-0031-1

摘要: Function and principle innovation is the ultimate innovation of a product. To achieve Function and principle innovation design of mechanical products, a new process model of function and principle solving is proposed, based on TRI

关键词: TRI     principle solving     product     principle innovation     ultimate innovation    

Effect of mineral additives and permeability reducing admixtures having different action mechanisms on

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1277-1291 doi: 10.1007/s11709-021-1752-2

摘要: In this paper, the effect of usage of the permeability reducing admixture (PRA) having different action mechanisms on hardened state properties of cementitious systems containing mineral additives is examined. For this aim, three commercial PRAs were used during investigation. The effective parameters in the first and third PRAs were air-entraining and high-rate air-entraining, respectively. The second one contained the insoluble calcium carbonate residue and had a small amount of the air-entraining property. Mortar mixes with binary and ternary cementitious systems were prepared by partially replacing cement with fly ash and metakaolin. The hardened state properties of mortar mixtures such as compressive strength, ultrasonic pulse velocity, water absorption, drying shrinkage and freeze–thaw resistance were investigated. The ternary cement-based mixture having both fly ash and metakaolin was selected as the most successful mineral-additive bearing mix in regard to hardened state properties. In this sense, PRA-B, with both insoluble residues and a small amount of air-entraining properties, showed the best performance among the mixtures containing PRA. The combined use of mineral additive and PRA had a more positive effect on the properties of the mixes.

关键词: cementitious system     mineral additive     permeability reducing admixture     mechanical properties     durability performance    

Principle of maximum entropy for reliability analysis in the design of machine components

Yimin ZHANG

《机械工程前沿(英文)》 2019年 第14卷 第1期   页码 21-32 doi: 10.1007/s11465-018-0512-z

摘要: We studied the reliability of machine components with parameters that follow an arbitrary statistical distribution using the principle of maximum entropy (PME). We used PME to select the statistical distribution that best fits the available information. We also established a probability density function (PDF) and a failure probability model for the parameters of mechanical components using the concept of entropy and the PME. We obtained the first four moments of the state function for reliability analysis and design. Furthermore, we attained an estimate of the PDF with the fewest human bias factors using the PME. This function was used to calculate the reliability of the machine components, including a connecting rod, a vehicle half-shaft, a front axle, a rear axle housing, and a leaf spring, which have parameters that typically follow a non-normal distribution. Simulations were conducted for comparison. This study provides a design methodology for the reliability of mechanical components for practical engineering projects.

关键词: machine components     reliability     arbitrary distribution parameter     principle of maximum entropy    

Study on the action of resistin-induced human umbilical vein endothelial cell dysfunction

LI Zhizhen, LI Fangping, YAN Li, LI Feng, LI Yan, CHENG Hua, FU Zuzhi

《医学前沿(英文)》 2007年 第1卷 第2期   页码 196-199 doi: 10.1007/s11684-007-0037-z

摘要: The aim of this paper was to investigate the effects of resistin on human umbilical vein endothelial cells (HUVECs), and to explore its role and mechanism of action in atherosclerosis. HUVECs were incubated with recombinant human resistin (0, 50, 100 ng/mL) for 24 h. ICAM-1, VCAM-1 and reactive oxygen species (ROS) were assayed by flow cytometer. ET-1, eNOS and iNOS mRNA expression were measured by semi-quantitative RT-PCR. Incubation of HUVECs with resistin resulted in an increase in ICAM-1 expression and ET-1 mRNA expression. However, resistin had no effect on VCAM-1 expression and ROS release. eNOS and iNOS mRNA expression were not altered by resistin stimulation. Adipokine resistin exerted a direct effect in promoting HUVEC dysfunction by promoting ICAM-1 and ET-1 expression. These data suggest that adipocyteendothelium cross-talk might play an important role in the pathogenesis of cardiovascular disease in diabetes mellitus.

关键词: endothelial     resistin stimulation     Incubation     pathogenesis     dysfunction    

Day-ahead electricity price forecasting using back propagation neural networks and weighted least square

S. Surender REDDY,Chan-Mook JUNG,Ko Jun SEOG

《能源前沿(英文)》 2016年 第10卷 第1期   页码 105-113 doi: 10.1007/s11708-016-0393-y

摘要: This paper proposes the day-ahead electricity price forecasting using the artificial neural networks (ANN) and weighted least square (WLS) technique in the restructured electricity markets. Price forecasting is very important for online trading, e-commerce and power system operation. Forecasting the hourly locational marginal prices (LMP) in the electricity markets is a very important basis for the decision making in order to maximize the profits/benefits. The novel approach proposed in this paper for forecasting the electricity prices uses WLS technique and compares the results with the results obtained by using ANNs. To perform this price forecasting, the market knowledge is utilized to optimize the selection of input data for the electricity price forecasting tool. In this paper, price forecasting for Pennsylvania-New Jersey-Maryland (PJM) interconnection is demonstrated using the ANNs and the proposed WLS technique. The data used for this price forecasting is obtained from the PJM website. The forecasting results obtained by both methods are compared, which shows the effectiveness of the proposed forecasting approach. From the simulation results, it can be observed that the accuracy of prediction has increased in both seasons using the proposed WLS technique. Another important advantage of the proposed WLS technique is that it is not an iterative method.

关键词: day-ahead electricity markets     price forecasting     load forecasting     artificial neural networks     load serving entities    

Emerging contaminant control: From science to action

《环境科学与工程前沿(英文)》 2022年 第16卷 第6期 doi: 10.1007/s11783-022-1559-y

摘要: Since the concept of emerging contaminants (ECs) was first proposed in 2001, the global scientific research of ECs has developed rapidly. In the past decades, great progress has been achieved in the scientific research of ECs in China, including the establishment of EC analysis method system, the evaluation of the pollution status, pollution characteristics and environmental risk of ECs in typical regions of China, and establishment of EC control technology system. Continuous progress in scientific research of ECs promoted China’s action on EC control. It is planned that the environmental risk of ECs will be generally controlled by 2035 in China. Priority ECs should be screened for environmental management. Although great efforts have been made, the EC control in China still faces tremendous challenges. It is necessary to bridge the gap between scientific research and decision-making management. Based on the science and technology study, various measures such as engineering, policy management and public participation should be combinedly adopted for EC control.

关键词: Emerging contaminants     Priority pollutants     PPCPs     POPs     Control policy    

Study of the mechanics of progressive collapse of FPB isolated beam-pier substructures

Jingcai ZHANG; Yong DING; Xinchun GUAN

《结构与土木工程前沿(英文)》 2022年 第16卷 第6期   页码 718-728 doi: 10.1007/s11709-022-0815-3

摘要: The horizontal stiffness of the isolated layer is reduced substantially by a friction pendulum bearing (FPB) toprotectthe structure from potential damages caused by earthquakes. However, horizontal stiffness is essential to progressive collapse resistance of structures. This paper presents a simplified model to assess the progressive collapse response of beam-pier substructure isolated by FPB. Progressive collapse resistance by flexural action of the beam and additional resistance owing to the horizontal restraining force was achieved. The influences of the equivalent radius and friction coefficient of the FPB, the applied axial force on the FPB, and span-depth ratio of the beam on the additional resistance were investigated. Simulations were conducted to verify the proposed model. The results show that progressive collapse resistance provided by horizontal restraining can be reduced as large as 46% and 88% during compressive arching action (CAA) and catenary action (CA), respectively. The equivalent radius of the FPB shows limited effect on the progressive collapse response of FPB isolated structures, but friction coefficient and applied axial force, as well as depth ratio of the beam, show significant influences on the additional progressive collapse resistance capacity. Finite element method (FEM) results are in good agreement with the result obtained by the proposed method.

关键词: friction pendulum bearing     progressive collapse     horizontal stiffness     compressive arching action     catenary action    

工程项目供应链的委托-代理模型分析

吴育华,张庆民

《中国工程科学》 2008年 第10卷 第5期   页码 75-78

摘要:

从委托代理理论出发,对基于集成化供应链的委托-代理模型的一般形式进行讨论。在此基础上,结合工程项目集成化供应链中委托方和代理方的特点构建了工程项目供应链单期委托-代理模型和多阶段工程项目供应链声誉模型。

关键词: 委托-代理模型     激励模型     声誉模型     随机行走    

中国工程院推出“院士行动”计划

《中国工程科学》 1999年 第1卷 第1期   页码 107-107

铁路隧道建设理念和设计原则

王梦恕,张梅

《中国工程科学》 2009年 第11卷 第12期   页码 4-8

摘要:

铁路隧道的建设正处于前所未有的大发展时期,笔者在总结大量工程成功经验和失败教训的基础上提出了铁路隧道建设的基本理念:隧道必须建成遗产工程;隧道必须进行科学的风险评估;隧道建设必须合理工期、合理造价、合理合同、合理施工方案和设计原则;隧道必须进行信息化施工。提出了单双线隧道选择、隧道纵坡及辅助导洞设置、支护结构设计以及快速施工等隧道设计原则。隧道建设的理念和设计原则可指导今后铁路隧道的规划、设计和施工。

关键词: 铁路隧道     建设理念     设计原则    

标题 作者 时间 类型 操作

General Optimal Trajectory Planning: Enabling Autonomous Vehicles with the Principle of Least Action

Heye Huang,Yicong Liu,Jinxin Liu,Qisong Yang,Jianqiang Wang,David Abbink,Arkady Zgonnikov,

期刊论文

迈向L5级自动驾驶汽车的发展原则

王建强, 黄荷叶, 李克强, 李骏

期刊论文

Theory and method of mechanism system design

Huijun ZOU, Qinghua LIANG, Qing ZHANG

期刊论文

View-invariant human action recognition via robust locally adaptive multi-view learning

Jia-geng FENG,Jun XIAO

期刊论文

China released the Action Plan on Prevention and Control of Soil Pollution

Fang Zhang,Guanghe Li

期刊论文

Function and principle innovative design of mechanical products based on TRIZ/FA

YUAN Feng, WANG Tai-yong, NIE Hui-juan

期刊论文

Effect of mineral additives and permeability reducing admixtures having different action mechanisms on

期刊论文

Principle of maximum entropy for reliability analysis in the design of machine components

Yimin ZHANG

期刊论文

Study on the action of resistin-induced human umbilical vein endothelial cell dysfunction

LI Zhizhen, LI Fangping, YAN Li, LI Feng, LI Yan, CHENG Hua, FU Zuzhi

期刊论文

Day-ahead electricity price forecasting using back propagation neural networks and weighted least square

S. Surender REDDY,Chan-Mook JUNG,Ko Jun SEOG

期刊论文

Emerging contaminant control: From science to action

期刊论文

Study of the mechanics of progressive collapse of FPB isolated beam-pier substructures

Jingcai ZHANG; Yong DING; Xinchun GUAN

期刊论文

工程项目供应链的委托-代理模型分析

吴育华,张庆民

期刊论文

中国工程院推出“院士行动”计划

期刊论文

铁路隧道建设理念和设计原则

王梦恕,张梅

期刊论文