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mODELING AND FORECASTING OF STOCK mARKETS UNDER A SYSTEm ADAPTATION FRAmEWORK

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Journal of Systems Science & Complexity 2012年第4期25卷 641-674页

作者： Xiaolian ZHENG ben m.chen The Department of Electrical & Computer Engineering The National University of Singapore

This paper adopts the concept of dynamic feedback systems to model the behavior of financial markets, or more specifically, the stock market from a dynamic system point of view. Based on a feedback adaptation scheme, the authors model the movement of a stock market index within a framework that is composed of an internal dynamic model and an adaptive filter. The output-error model is adopted as the internal model whereas the adaptive filter is a time-varying state space model with instrumental variables. Its input-output behavior, and internal as well as external forces are then identified. Special attention has also been paid to the recent financial crisis by examining the movement of Dow Jones Industrial Average （DJIA） as an example to illustrate the advantage of the proposed framework. Supported by time-varying causality tests, five influential factors from economic and sentiment aspects are introduced as the input of this framework. Testing results show that the proposed framework has a much better prediction performance than the existing methods, especially in complicated economic situations. An application of this framework is also presented with focuses on forecasting the turning periods of the market trend. Realizing that a market trend is about to change when the external force begins to exhibit clear patterns in its frequency responses, the authors develop a set of rules to recognize this kind of clear patterns. These rules work well for stock indexes from US, China and Singapore.

关键词： Complex systems financial modeling financial systems market forecasting system economics.

On the Trends of Autonomous Unmanned Systems Research

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Engineering 2022年第5期8卷 20-23页

作者： ben m.chen Department of mechanical and Automation Engineering The Chinese University of Hong KongHong Kong 999077China

In recent decades,academia and industry have put increasing attention and investment into the research and development of autonomous unmanned *** autonomous unmanned vehi-cle is a machine equipped with necessary data-processing units,sophisticated sensors,environment perception,automatic control,motion planning,task planning,mission management,and com-munication systems.

关键词： autonomous systems equipped

Online schedule for autonomy of multiple unmanned aerial vehicles

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Science China(Information Sciences) 2017年第7期60卷 217-229页

作者： Kemao PENG Feng LIN ben m.chen Temasek Laboratories National University of Singapore Department of Electrical and Computer Engineering National University of Singapore

An online rectangle based scheduling algorithm(RSA) is developed to improve autonomy of multiple unmanned aerial vehicles(UAVs) to search a field of forest together. The purposes of RSA are to online decide the number of the UAVs to be assigned and to schedule the path for the assigned UAVs to search the missed areas resulted from the previous search. The main ideas of RSA are to cover each separated zone of the missed areas with a rectangle and then to schedule the path to search the rectangles. Thus, RSA is robust against the unknown shapes and sizes of the missed areas. The forest search is applied to verify the online RSA in simulation. The simulation results demonstrate that the online RSA is successful to decide the number of the UAVs to be assigned and to schedule the path for the assigned UAVs to search the missed areas.

关键词： online schedule mission planning autonomy of UAVs multiple UAVs algorithms

Autonomous reconfigurable hybrid tail-sitter UAV U-Lion

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Science China(Information Sciences) 2017年第3期60卷 202-217页

作者： Kangli WANG Yijie KE ben m.chen Unmanned Systems Research Group 4 Engineering Drive 3 National University of Singapore

We present in this work the development of a novel hybrid unmanned aircraft platform, U-Lion,which has both vertical take-off and landing(VTOL) and cruising flight capabilities. Our design is in tail-sitter structure with reconfigurable wings, which combines the advantages of a fixed-wing plane and a rotor helicopter effectively. This allows it to transit from vertical take-off to hovering, before flying in cruise mode for efficient long duration flight. The propulsion comes from two coaxial contra-rotating motors fixed on a gimbal mechanism,which can change the direction of the motors for the required thrust. This thrust-vectored propulsion system primarily provides control in the VTOL mode but also enhances flight capabilities in the cruise mode. The hybrid aircraft is equipped with GPS and airspeed sensors, and has an onboard avionic system with advanced flight control algorithms to perform fully autonomous VTOL and cruising flights, in addition to transiting effectively between VTOL and cruising flight modes. The overall design has been successfully verified by actual flight experiments.

关键词： unmanned aerial vehicle vertical take-off and landing hybrid platform aircraft platform design flight control system

Smooth quadrotor trajectory generation for tracking a moving target in cluttered environments

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Science China(Information Sciences) 2021年第7期64卷 132-147页

作者： Lele XI Zhihong PENG Lei JIAO ben m.chen School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System Peng cheng Laboratory Department of mechanical and Automation Engineering The Chinese University of Hong Kong

In this paper, we present a trajectory generation method of a quadrotor, based on the optimal smoothing B-spline, for tracking a moving target with consideration of relative tracking pattern or limited field of view of the onboard sensor in cluttered environments. Compared to existing methods, safe flying zone,vehicle physical limits, and smoothness are fully considered to guarantee flight safety, kinodynamic feasibility, and tracking performance. To tackle the cluttered environments, a parallel particle swarm optimization algorithm is applied to find the feasible waypoints that the generated trajectory should be as close to as possible, with consideration of the target’s future state as well as obstacles to trade off the tracking performance and flight safety. Then, a sequential motion planning method, considering the above constraints, is applied and embedded into a cost function for solving the problem of robust tracking trajectory generation for the quadrotor via a convex optimization approach. The feasibility and effectiveness of the proposed method are verified by numerical simulations.

关键词： quadrotor target tracking trajectory generation B-spline convex optimization

Semi-global leader-following output consensus of heterogeneous systems subject to actuator position and rate saturation

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Autonomous Intelligent Systems 2021年第1期1卷 91-103页

作者： Panpan Zhou ben m.chen Department of mechanical and Automation Engineering The Chinese University of Hong KongShatinN.T.Hong Kong

We study in this paper a semi-global leader-following output consensus problem for multiple heterogeneous linear systems in the presence of actuator position and rate saturation over a directed *** each follower,via the low gain feedback design technique and output regulation theory,both a state feedback consensus protocol and an output feedback consensus protocol are *** the output feedback case,different distributed observers are designed for the informed followers and uninformed followers to estimate the state of the leader and the follower *** show that the semi-global leader-following output consensus of heterogeneous linear systems can be achieved by the two consensus protocols if each follower is reachable from the leader in the directed communication topology.

关键词： multi-agent system Output consensus Low gain feedback

Complex system and intelligent control: theories and applications

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 1-3页

作者： Jie chen ben m.chen Jian SUN School of Automation Beijing Institute of Technology Tongji University Department of mechanical and Automation Engineering Chinese University of Hong Kong Department of Electrical and Computer Engineering National University of Singapore

Complex systems are the systems that consist of a great many diverse and autonomous but interacting and interdependent components whose aggregate behaviors are nonlinear. As phased by Aristotle,'the whole is more than the sum of its parts;' properties of complex systems are not a simple summation of their individual *** systems are widespread. Typical examplesofcomplexsystemscanbefoundinthehuman brain,flocking formation of migrating birds,power grid,transportation systems,autonomous vehicles,social networks, and communication networks.

关键词： Complex system and intelligent control theories and applications UAV

A hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction

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Control Theory and Technology 2024年第3期22卷 394-405页

作者： Chuanxiang Gao Xinyi Wang Xi chen ben m.chen Department of mechanical and Automation Engineering The Chinese University of Hong KongHong KongShatinNTChina

Unmanned aerial vehicles(UAVs)are emerging as a powerful tool for inspections and repair works in large-scale and unstructured 3D infrastructures,but current approaches take a long time to cover the entire *** using UAVs for inspections and repair works puts forward a requirement of improving time efficiency in large-scale and cluster *** paper presents a hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction to balance the workload and reduce the overall task completion *** proposed framework consists of two stages,the exploration stage and the exploitation stage,resolving the task in a sequential *** the exploration stage,the density map is developed to update global and local information for dynamic load-balanced area partition based on reconstructability and relative positions of UAVs,and the Voronoi-based planner is used to enable the UAVs to reach their best *** obtaining the global map,viewpoints are generated and divided while taking into account the battery capacity of each ***,a shortest path planning method is used to minimize the total traveling cost of these viewpoints for obtaining a high-quality *** experiments are conducted in both a simulated and real environment to show the time efficiency,robustness,and effectiveness of the proposed ***,the whole system is implemented in real applications.

关键词： multi-UAV Coverage path planning Infrastructure inspection and reconstruction

Safe navigation of quadrotors with jerk limited trajectory

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 107-119页

作者： Shu-peng LAI meng-lu LAN Ya-xuan LI ben m.chen Department of Electrical and Computer Engineering National University of Singapore Graduate School for Integrative Science & Engineering National University of Singapore School of Control Science and Engineering Shandong University Department of mechanical and Automation Engineering Chinese University of Hong Kong

many aerial applications require unmanned aerial systems operate in safe zones because of the presence of obstacles or security regulations. It is a non-trivial task to generate a smooth trajectory satisfying both dynamic constraints and motion limits of the unmanned vehicles while being inside the safe zones. Then the task becomes even more challenging for real-time applications, for which computational efficiency is crucial. In this study, we present a safe flying corridor navigation method, which combines jerk limited trajectories with an efficient testing method to update the position setpoints in real time. Trajectories are generated online and incrementally with a cycle time smaller than 10 μs, which is exceptionally suitable for vehicles with limited onboard computational capability. Safe zones are represented with multiple interconnected bounding boxes which can be arbitrarily *** jerk limited trajectory generation algorithm has been extended to cover the cases with asymmetrical motion limits. The proposed method has been successfully tested and verified in flight simulations and actual experiments.

关键词： Quadrotor Unmanned aerial vehicle motion planning