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SSRN 2022年

作者： Liu, Tao Ji, Wen Gkiotsalitis, Konstantinos Cats, Oded National Engineering Laboratory of Integrated Transportation Big Data Application Technology School of Transportation and Logistics Southwest Jiaotong University Chengdu611756 China Institute of System Science and Engineering School of Transportation and Logistics Southwest Jiaotong University Chengdu611756 China Department of Civil Engineering Faculty of Engineering Technology University of Twente Horst Complex Z222 P.O. Box 217 Enschede 7500 AE Netherlands Department of Transport & Planning Delft University of Technology Netherlands

Timetabling and vehicle scheduling are two important activities in public transport (PT) operations planning. Traditionally, the timetabling problem is solved first before proceeding to the vehicle scheduling problem. The integration of these two problems can help further reduce the total operation cost and improve the level of service, especially when timetables of different bus lines are well-coordinated at transfer stations. This work addresses the integrated PT timetable coordination and vehicle scheduling problem while ensuring that each PT line is dispatched with an even headway. We first separately formulate two integer linear programming models for the timetable coordination and vehicle scheduling problems. Next, the two models are combined into a bi-objective integer linear programming model for the integrated timetable coordination and vehicle scheduling problem. For small size PT networks, the model can be solved by using an ɛ -constraint method, together with off-the-shelf optimization solvers. For large-size problems, two constraint reduction procedures are developed to reduce the number of redundant constraints so as to reduce the computation complexity and improve the solution process. Finally, the models and solution method are applied to a numerical example and a real-world bus rapid transit (BRT) network in Chengdu, China. Computation results show that the solution generated by the sequential optimization approach is usually dominated by the Pareto-optimal solutions generated by the integrated optimization approach. Our findings suggest that it is not a wise decision to use the solution generated by the sequential optimization approach or the solution with the minimum fleet size generated by the integrated optimization approach. For practical implementation, it is recommended to choose the solution that has a fleet size of one more vehicle than the minimum fleet size. © 2022, The Authors. All rights reserved.

关键词： Integer programming

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Ship Target Signature Indication based on complex Signal Kurtosis in SAR Images

Ship Target Signature Indication based on Complex Signal Kur...

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IEEE International Symposium on Geoscience and Remote Sensing (IGARSS)

作者： Xiangguang Leng Kefeng Ji Boli Xiong Gangyao Kuang State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System College of Electronic Science and technology National University of Defense Technology Changsha China

ISBN: (数字)9781728163741

ISBN: (纸本)9781728163758

Recently, complex signal kurtosis (CSK) is found to be a vital indicator of ship detection in synthetic aperture radar (SAR) images. Since CSK can be used as an indicator of ship detection, we consider it can also be used to indicate ship target signature. One of the basic rationales is that the higher the CSK is, the easier it is to be detected and thus the more obvious its characteristics are as a ship. Presence of sidelobes and defocusing are two common problems that affect the quality of ship targets. They are discussed in this paper from the perspective of CSK. Experimental results show that CSK can be used to indicate and improve ship quality. We believe that ship detection and recognition can benefit from the CSK indicator.

关键词： Marine vehicles Radar polarimetry Synthetic aperture radar Azimuth Remote sensing Random variables Spaceborne radar

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A Solution Analysis of U.S. Weapon Equipment systems-of-systems Development and Application

A Solution Analysis of U.S. Weapon Equipment Systems-of-Syst...

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International Conference on Information science and Control Engineering (ICISCE)

作者： Menglong Lin Shuanghui Yi Mengmeng Zhang Zhen Shu Science and Technology on Information Systems Engineering Laboratory National University of Defense Technology Changsha China National Key Laboratory for Complex System Simulation Beijing China

In recent years, the development and deployment of the U.S. weapon equipment systems-of-systems (SoS) have yielded rich research results. However, there are still large gaps in the SoS development, joint testing, and design and acquisition of our own equipment SoS. The barriers of these steps have not yet been opened up. This article mainly analyzes the solutions of the U.S. weapon equipment SoS from three aspects, such as capability-based requirement generation and architecture design technology, interconnected-oriented integration test technology, and weapon equipment design and acquisition technology based on complex adaptive systems. We explore key technologies involved in order to form an overall understanding and explore related research approaches.

关键词： Technological innovation Adaptive systems Weapons Agent-based modeling Planning Sustainable development system analysis and design

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Range migration-based Doppler ambiguous integer estimation for moving targets with azimuth spectrum aliasing 6

Range migration-based Doppler ambiguous integer estimation f...

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6th Asia-Pacific Conference on Synthetic Aperture Radar, APSAR 2019

作者： Zhang, Ying Xiong, Wei Dong, Xichao Hu, Cheng Liu, Chengxiang Sun, Yang Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China School of Information and Electronics Beijing Institute of Technology Beijing China

ISBN: (纸本)9781728129129

In some case, the azimuth spectrum bandwidth is larger than the pulse repetition frequency (PRF), leading to a whole azimuth spectrum has been folded into multiple subsegments and aliased. Therefore, the traditional Doppler ambiguous integer estimation method cannot be used directly. In this paper, the influence of Doppler ambiguous integer on residual range migrations' slope is analyzed. Based on the slope, the Doppler ambiguous integer estimation method for moving targets with azimuth spectrum aliasing is given. From the simulation results, the Doppler ambiguous integer can be estimated accurately by proposed method. © 2019 IEEE.

关键词： Synthetic aperture radar

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An Anti-Rolling Control Method of Rudder Fin system Based on Adrc Decoupling and Ddpg Parameter Adjustment

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SSRN 2022年

作者： Sun, Mingxiao Zhang, Wenyu Zhang, Yongde Luan, Tiantian Yuan, Xiaoliang Li, Xiaogang School of Automation Harbin University of Science and Technology No.52 Xuefu Road Nangang District Heilongjiang Province Harbin City150080 China Heilongjiang Provincial Key Laboratory of Complex Intelligent System and Integration Harbin University of Science and Technology No.52 Xuefu Road Nangang District Heilongjiang Province Harbin City150080 China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of Education Harbin University of Science and Technology No.52 Xuefu Road Nangang District Heilongjiang Province Harbin City150080 China Wuxi CREG Urban Rail Transit Equipment Co. Ltd No. 1061 Jiaoshan Road Xishan Development Zone Jiangsu Province Wuxi214000 China

To achieve high-precision attitude control of ships, the output delay, state coupling, and controller parameter maladjustment of the rudder fin joint anti-rolling system are studied. A predictive anti-rolling method based on active disturbance rejection control (ADRC) and deep deterministic policy gradient (DDPG) is proposed. The external forces on the ship are analyzed, and a three-degree-of-freedom mathematical model considering rolling, yawing, and pitching is established. The model is decoupled using the idea of ADRC total disturbance for the state coupling problem, then the pitch ADRC controller and the roll-yaw predictive observer are designed respectively. In pitch ADRC, the nonlinear extended state observer (NLESO) is used to observe the total disturbance between models. And the total disturbance observations are feedforward compensated to the error control law. As a result, the rapidity of reference output tracking and robustness of total disturbance are realized. The roll-yaw predictive observer solves the output delay by feeding the predicted output back to the controller instead of the actual output. To ensure the accuracy of the prediction output, the DDPG algorithm is introduced to modify the parameters of the prediction observer in real-time. Finally, state constraints are added to solve the rudder angle and fin angle control laws. © 2022, The Authors. All rights reserved.

关键词： Controllers

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Point Cloud Preprocessing on 3D LiDAR data for Unmanned Surface Vehicle in Marine Environment

Point Cloud Preprocessing on 3D LiDAR data for Unmanned Surf...

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Information technology,Big Data and Artificial Intelligence (ICIBA), International Conference on IEEE International Conference on

作者： Xianzhi Qi Wenxing Fu Pei An Bingli Wu Jie Ma National Key Laboratory of Science and Technology on Multispectral Information Processing School of Artificial Intelligence and Automation Huazhong University of Science and Technology Wuhan China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing China

ISBN: (数字)9781728152240

ISBN: (纸本)9781728152257

Point cloud preprocessing is still a challenging task in the marine environment, for it is difficult to filter out non-obstacle points while avoiding damage to the obstacle completeness. In this paper, we propose a novel data preprocessing method on 3D LiDAR data for the unmanned surface vehicle in the marine environment. It consists of two tasks: outlier removal and wake filtering. As the spatial resolution of LiDAR changes with distance, we exploit distance normalization on statistical outlier filter for robust outlier removal. Considering the gradient difference between wave wake and obstacle surface near the water, we define and calculate the vertical state of point cloud on the range image to obtain the pre-filtering point set, and then use the RANSAC method to filter out the wake points. Experiments on real data has demonstrated the effectiveness of the proposed algorithm both in terms of feasibility and accuracy.

关键词： Three-dimensional displays Laser radar Filtering Filtering algorithms Spatial resolution Task analysis Measurement by laser beam

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A digital image correlation method for strain measurement using higher-order X-ray optical field components

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Optics and Laser technology 2025年 189卷

作者： Li, Zixin Su, Yong Li, Jia Yuan, Yajun Xiao, Yu Xu, Feng CAS Key Laboratory of Mechanical Behaviour and Design of Materials Department of Modern Mechanics CAS Center for Excellence in Complex System Mechanics University of Science and Technology of China Anhui Hefei230027 China School of Biomedical Engineering Anhui Medical University Hefei230032 China

To achieve highly sensitive characterization of internal material strain fields, this study proposes a digital image correlation strain field measurement method based on higher-order X-ray optical field *** method utilizes random gratings to modulate the X-ray optical field, extracts the information of higher-order field components during material deformation based on the discrepancy between the theoretical transmission model and the experimental measurement, and combines the extracted information with Digital Image Correlation (DIC) technology to achieve precise measurement of internal material strain *** to the experimental comparison and verification, the relative displacement difference between the deformation field distribution obtained by the proposed method and the results of the traditional absorption phase method in the non-boundary and stress concentration area proves that the correlation information of the higher order components can truly reflect the deformation characteristics of the ***, compared to traditional methods, this method demonstrates higher sensitivity in strain field characterization. Particularly in the measurement of shear strain at crack tips, its computational results align more closely with linear elastic fracture mechanics theoretical predictions, providing a novel experimental approach for studying material damage evolution and failure mechanisms. © 2025 Elsevier Ltd

关键词： Crack tips

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Automatic Sleep Spindle Detection and Analysis in Patients with Sleep Disorders 1

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2nd International Workshop on Human Brain and Artificial Intelligence, HBAI 2020 held in Conjunction with IJCAI-PRICAI 2020

作者： Chen, Chao Zhu, Xuequan Belkacem, Abdelkader Nasreddine Lu, Lin Hao, Long You, Jia Shin, Duk Tan, Wenjun Huang, Zhaoyang Ming, Dong Academy of Medical Engineering and Translational Medicine Tianjin University Tianjin300072 China Key Laboratory of Complex System Control Theory and Application Tianjin University of Technology Tianjin300384 China Department of Computer and Network Engineering College of Information Technology UAE University Al Ain15551 United Arab Emirates Zhonghuan Information College Tianjin University of Technology Tianjin300380 China Department of Electronics and Mechatronics Tokyo Polytechnic University Atsugi243-0297 Japan School of Computer Science and Engineering Northeastern University Shenyang110189 China Department of Neurology Xuanwu Hospital Capital Medical University Beijing100088 China

ISBN: (数字)9789811612886

ISBN: (纸本)9789811612879

Nowadays, Sleep disorder is a common disease, and spindle spindles are important features of the second stage non-rapid eye movement (NREM) sleep. In this paper, we propose an improved automatic detection method of spindles based on wavelet transform. The spindles automatic detector is mainly composed of wavelet transform and clustering. We collected the electroencephalography (EEG) signals of six patients with sleep disorders all night for ten hours, and then preprocessed the data and other operations, and then used our improved method to detect the sleep EEG signals by spindles. By comparing with the previous automatic detection method not improved and another automatic detection method, the results show that the accuracy of sleep spindles detection can be effectively improved. The accuracy of the improved detector is 5.19% higher than before, and 9.7% higher than that of another method based on amplitude threshold. Finally, we made a simple comparison between people with sleep disorders and normal people. We found that there were significant differences in spindle density between people with sleep disorders and people without sleep disorders. The average spindle density in the normal population averaged 2.59 spindles per minute. People with sleep disorders had an average spindle density of 1.32 spindles per minute. In future research, our research direction is to improve the accuracy of spindles automatic detection by improving the spindles detector and study the difference of spindles between patients with sleep disorders and normal people in a large number of samples, so that the difference of spindles can be used as the basis for the diagnosis of sleep disorders. © 2021, Springer Nature Singapore Pte Ltd.

关键词： Wavelet transforms

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Self-Tuning Attitude Control Design of Hypersonic Aircraft with Multi-Constraints Based on Soft-Constrained PI2 with Action Smooth

Self-Tuning Attitude Control Design of Hypersonic Aircraft w...

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Chinese Automation Congress (CAC)

作者： Tianyi Li Jiajun Fan Xian Guo Mingrui Hao Mingwei Sun College of Artificial Intelligence Nankai University Tianjin China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Bejing China

ISBN: (数字)9781728176871

ISBN: (纸本)9781728176888

Nonlinear control has led to several great achievements for attitude control in virtual simulation environments, where the system model can be simplified to meet the application condition of those traditional nonlinear control algorithms. However, only a few of those algorithms can be applied to a practical Hypersonic Aircraft system, which suffers from uncertainties, multi-constraints, and various noises. To solve those problems effectively, in this paper, a novel reinforcement learning framework based on PI2 is proposed, wherein three kernel techniques are introduced. Firstly, a generalized path- integral-control approach is proposed to obtain the numerical solution of a stochastic dynamic model, wherein the calculation of the gradient and matrix inversion is avoided to ensure fast and reliable training convergence. Secondly, an action smooth method is used to strengthen the ability of the controller to resist noise. Thirdly, a novel RL algorithm combined with soft constrained techniques is illustrated to address the constrained nonlinear control problem. Several experiments are carried out and analyzed to demonstrate the outstanding performance of the CS-PI2.

关键词： Training Uncertainty Attitude control Atmospheric modeling Stochastic processes Resists Aircraft

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Finite Time Cooperative Guidance Law for Multiple UAVs with Intermittent Communication Topologies

Finite Time Cooperative Guidance Law for Multiple UAVs with ...

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2019 IEEE International Conference on Unmanned systems, ICUS 2019

作者： Lyu, Teng Xu, Cheng Li, Hongchun Hu, Song Zhang, Daochi System Control and Intelligent Agent Cooperation Laboratory Science and Technology on Complex Beijing China Beijing Electro-mechanical Engineering Institute Beijing China

ISBN: (纸本)9781728137926

To solve the problem of multiple Unmanned Aerial Vehicles (UAVs) with intermittent communication topologies simultaneously attack a stationary target, a time cooperative guidance law is studied in this paper. First, a novel time cooperative guidance model for multiple UAVs is constructed based on UAVs-target relative motion equations. Then, a cooperative guidance law is designed based on consensus theory, which can ensure multiple UAVs' impact times realize finite time consensus under intermittent topologies. After UAVs' impact times become to be the same, traditional PN guidance law is applied in all UAVs to guarantee that the UAVs can attack the target precisely without influencing the consensus of impact times. Finally, the validity of the proposed method is shown by numerical simulations. © 2019 IEEE.

关键词： Topology

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