Multiple Uninhabited Aerial Vehicles (multi-UAVs) coordinated trajectory replanning is one of the most complicated global optimum problems in multi-UAVs coordinated control. Based on the construction of the basic mode...Multiple Uninhabited Aerial Vehicles (multi-UAVs) coordinated trajectory replanning is one of the most complicated global optimum problems in multi-UAVs coordinated control. Based on the construction of the basic model of multi-UAVs coordinated trajectory replanning, which includes problem description, threat modeling, constraint conditions, coordinated function and coordination mechanism, a novel Max-Min adaptive Ant Colony Optimization (ACO) approach is presented in detail. In view of the characteristics of multi-UAVs coordinated trajectory replanning in dynamic and uncertain environments, the minimum and maximum pheromone trails in ACO are set to enhance the searching capability, and the point pheromone is adopted to achieve the collision avoidance between UAVs at the trajectory planner layer. Considering the simultaneous arrival and the air-space collision avoidance, an Estimated Time of Arrival (ETA) is decided first. Then the trajectory and flight velocity of each UAV are determined. Simulation experiments are performed under the complicated combating environment containing some static threats and popup threats. The results demonstrate the feasibility and the effectiveness of the proposed approach.展开更多
Field D* algorithm is widely used in mobile robot navigation since it can plan and replan any-angle paths through non-uniform cost grids. However, it still suffers from inefficiency and sub-optimality. In this article...Field D* algorithm is widely used in mobile robot navigation since it can plan and replan any-angle paths through non-uniform cost grids. However, it still suffers from inefficiency and sub-optimality. In this article, a new linear interpolation-based planning and replanning algorithm, Update-Reducing Field D*, is proposed. It employs different approaches during initial planning and replanning respectively in order to reduce the number of updates of the rhs-values of vertices. Experiments have shown that Update-Reducing Field D* runs faster than Field D* and returns smoother and lower-cost paths.展开更多
With the rapid changes of the flight environment and situation,there will be various unexpected situations while multiple missiles are performing the missions.To fast cope with the various situations in mission execut...With the rapid changes of the flight environment and situation,there will be various unexpected situations while multiple missiles are performing the missions.To fast cope with the various situations in mission executions,the conventional sequential convex programming algorithm and the parallel-based sequential convex programming algorithm for multiple missiles fast trajectory replanning are proposed in this paper.The originally non-convex trajectory optimization problem is reformulated into a series of convex optimization subproblems based on the sequential convex programming method.The conventional sequential convex programming algorithm is developed through linearization,successive convexification,and relaxation techniques to solve the convex optimization subproblems iteratively.However,multiple missiles are related through various cooperative constraints.When the trajectory optimization of multiple missiles is formulated as an optimal control problem to solve,the complexity of the problem will increase dramatically as the number of missiles increases.To alleviate the coupled effect caused by multiple aerodynamically controlled missiles,the parallel-based sequential convex programming algorithm is proposed to solve the trajectory optimization problem for multiple missiles in parallel,reducing the complexity of the trajectory optimization problem and significantly shortening the computation time.Numerical simulations are provided to verify the convergence and effectiveness of the conventional sequential convex programming algorithm and the parallel-based sequential convex programming algorithm to cope with the trajectory optimization problem with various constraints.Furthermore,the optimality and the real-time performance of the proposed algorithms are discussed in comparative simulation examples.展开更多
Recovery is a crucial supporting process for carrier aircraft,where a reasonable landing scheduling is expected to guide the fleet landing safely and quickly.Currently,there is little research on this topic,and most o...Recovery is a crucial supporting process for carrier aircraft,where a reasonable landing scheduling is expected to guide the fleet landing safely and quickly.Currently,there is little research on this topic,and most of it neglects potential influence factors,leaving the corresponding supporting efficiency questionable.In this paper,we study the landing scheduling problem for carrier aircraft considering the effects of bolting and aerial refueling.Based on the analysis of recovery mode involving the above factors,two types of primary constraints(i.e.,fuel constraint and wake interval constraint)are first described.Then,taking the landing sequencing as decision variables,a combinatorial optimization model with a compound objective function is formulated.Aiming at an efficient solution,an improved firefly algorithm is designed by integrating multiple evolutionary operators.In addition,a dynamic replanning mechanism is introduced to deal with special situations(i.e.,the occurrence of bolting and fuel shortage),where the high efficiency of the designed algorithm facilitates the online scheduling adjustment within seconds.Finally,numerical simulations with sufficient and insufficient fuel cases are both carried out,highlighting the necessity to consider bolting and aerial refueling during the planning procedure.Simulation results reveal that a higher bolting probability,as well as extra aerial refueling operations caused by fuel shortage,will lead to longer recovery complete time.Meanwhile,due to the strong optimum-seeking capability and solution efficiency of the improved algorithm,adaptive scheduling can be generated within milliseconds to deal with special situations,significantly improving the safety and efficiency of the recovery process.An animation is accessible at bilibili.com/video/BV1QprKY2EwD.展开更多
Multi-robot mission planning is composed of assignment allocation and mobile-robot route planning in this paper.Multi-robot exploration missions adopts fuzzy c-mean(FCM)algorithm to allocate,and then,heterogeneous int...Multi-robot mission planning is composed of assignment allocation and mobile-robot route planning in this paper.Multi-robot exploration missions adopts fuzzy c-mean(FCM)algorithm to allocate,and then,heterogeneous interactive cultural hybrid algorithm(HICHA)is devised for route planning in order to optimize mobilerobot execution path.Meanwhile,we design multi-robot mission replanning mechanism based on the rules system of greedy algorithm for dynamic stochastic increment missions.Finally,extensive simulation experiments were shown that FCM for assignment allocation and HICHA for route planning were efficacious for mobile-robot exploration mission planning.Furthermore,the improved greedy algorithm based on experience rules met dynamic stochastic increment missions replanning requirement for load balance.展开更多
A production planning system is designed for the whole steelmaking process, which includes desulfurization, vanadium extraction, steelmaking and continuous casting processes of Panzhihua Iron and Steel Corporation. Th...A production planning system is designed for the whole steelmaking process, which includes desulfurization, vanadium extraction, steelmaking and continuous casting processes of Panzhihua Iron and Steel Corporation. The system is composed of modeling module, data interface module, data analysis module, static planning module, re-planning module, plan evaluation module, plan simulation module and human-computer interaction module. The system is connected with the L3 system of steel plant by using the data interface module, which can receive the real time scheduling information to make the static plan and re-plan under production disturbances. The simulation and plan evaluation function of the system can assist decision-maker to check and modify the production plan. The simulation experiments with real process data show that the system can make a feasible, executable, and effective production plan, and deal with primary random disturbances during production process timely.展开更多
Breast cancer is the most frequent cancer among females and also a leading cause of cancer related mortality worldwide.A multimodality treatment approach may be utilized for optimal management of patients with combina...Breast cancer is the most frequent cancer among females and also a leading cause of cancer related mortality worldwide.A multimodality treatment approach may be utilized for optimal management of patients with combinations of surgery,radiation therapy(RT)and systemic treatment.RT composes an integral part of breast conserving treatment,and is typically used after breast conserving surgery to improve local control.Recent years have witnessed significant improvements in the discipline of radiation oncology which allow for more focused and precise treatment delivery.Adaptive radiation therapy(ART)is among the most important RT techniques which may be utilized for redesigning of treatment plans to account for dynamic changes in tumor size and anatomy during the course of irradiation.In the context of breast cancer,ART may serve as an excellent tool for patients receiving breast irradiation followed by a sequential boost to the tumor bed.Primary benefits of ART include more precise boost localization and potential for improved normal tissue sparing with adapted boost target volumes particularly in the setting of seroma reduction during the course of irradiation.Herein,we provide a concise review of ART for breast cancer in light of the literature.展开更多
For autonomous MUAV,the Ground Control Station(GCS)including hardware and modular software programming such as control modular,navigation modular,display modular and monitor modular becomes important equipment to be d...For autonomous MUAV,the Ground Control Station(GCS)including hardware and modular software programming such as control modular,navigation modular,display modular and monitor modular becomes important equipment to be developed.This paper emphasizes the global planning and the local replanning arithmetic based on three-dimensional velocity potential field for the moving threats.During the test on the ground and in the sky,GCS show the remote sensing information precisely and send the control command in time.The system can be used to assist in the function of autonomous complex task for MUAV.展开更多
The design of universal segments and deviation control of segment assembly are essential for robust and low-risk tunnel construction.A building information modeling(BIM)-based framework was proposed for parametric mod...The design of universal segments and deviation control of segment assembly are essential for robust and low-risk tunnel construction.A building information modeling(BIM)-based framework was proposed for parametric modeling,automatic assembly,and deviation control of universal segments.First,segment models of different levels of detail(LoDs)were built based on BIM visual programming language(VPL)for different project life cycles.Then,the geometric constraints,requirements,and procedures for parametric segment assembly were distilled to develop a program that combines a novel typesetting algorithm with a 3D path replanning algorithm.Typesetting is implemented by introducing a point indication matrix,characterizing segments by sides,and manipulating geometries in a VPL.Simultaneously,3D path replanning,with non-uniform rational B-splines(NURBS)and arcs as basic shapes,was used to resolve unacceptable deviation situations after typesetting.Finally,the proposed framework was validated on a water diversion line and was found to be more effective and accurate than the previous method.展开更多
基金supported by the Natural Science Foundation of China (Grant no.60604009)Aeronautical Science Foundation of China (Grant no.2006ZC51039,Beijing NOVA Program Foundation of China (Grant no.2007A017)+1 种基金Open Fund of the Provincial Key Laboratory for Information Processing Technology,Suzhou University (Grant no KJS0821)"New Scientific Star in Blue Sky"Talent Program of Beihang University of China
文摘Multiple Uninhabited Aerial Vehicles (multi-UAVs) coordinated trajectory replanning is one of the most complicated global optimum problems in multi-UAVs coordinated control. Based on the construction of the basic model of multi-UAVs coordinated trajectory replanning, which includes problem description, threat modeling, constraint conditions, coordinated function and coordination mechanism, a novel Max-Min adaptive Ant Colony Optimization (ACO) approach is presented in detail. In view of the characteristics of multi-UAVs coordinated trajectory replanning in dynamic and uncertain environments, the minimum and maximum pheromone trails in ACO are set to enhance the searching capability, and the point pheromone is adopted to achieve the collision avoidance between UAVs at the trajectory planner layer. Considering the simultaneous arrival and the air-space collision avoidance, an Estimated Time of Arrival (ETA) is decided first. Then the trajectory and flight velocity of each UAV are determined. Simulation experiments are performed under the complicated combating environment containing some static threats and popup threats. The results demonstrate the feasibility and the effectiveness of the proposed approach.
文摘Field D* algorithm is widely used in mobile robot navigation since it can plan and replan any-angle paths through non-uniform cost grids. However, it still suffers from inefficiency and sub-optimality. In this article, a new linear interpolation-based planning and replanning algorithm, Update-Reducing Field D*, is proposed. It employs different approaches during initial planning and replanning respectively in order to reduce the number of updates of the rhs-values of vertices. Experiments have shown that Update-Reducing Field D* runs faster than Field D* and returns smoother and lower-cost paths.
基金supported by the National Natural Science Foundation of China(Grant No.12372044).
文摘With the rapid changes of the flight environment and situation,there will be various unexpected situations while multiple missiles are performing the missions.To fast cope with the various situations in mission executions,the conventional sequential convex programming algorithm and the parallel-based sequential convex programming algorithm for multiple missiles fast trajectory replanning are proposed in this paper.The originally non-convex trajectory optimization problem is reformulated into a series of convex optimization subproblems based on the sequential convex programming method.The conventional sequential convex programming algorithm is developed through linearization,successive convexification,and relaxation techniques to solve the convex optimization subproblems iteratively.However,multiple missiles are related through various cooperative constraints.When the trajectory optimization of multiple missiles is formulated as an optimal control problem to solve,the complexity of the problem will increase dramatically as the number of missiles increases.To alleviate the coupled effect caused by multiple aerodynamically controlled missiles,the parallel-based sequential convex programming algorithm is proposed to solve the trajectory optimization problem for multiple missiles in parallel,reducing the complexity of the trajectory optimization problem and significantly shortening the computation time.Numerical simulations are provided to verify the convergence and effectiveness of the conventional sequential convex programming algorithm and the parallel-based sequential convex programming algorithm to cope with the trajectory optimization problem with various constraints.Furthermore,the optimality and the real-time performance of the proposed algorithms are discussed in comparative simulation examples.
基金the financial support of the National Natural Science Foundation of China(12102077,12161076)the Natural Science and Technology Program of Liaoning Province(2023-BS-061).
文摘Recovery is a crucial supporting process for carrier aircraft,where a reasonable landing scheduling is expected to guide the fleet landing safely and quickly.Currently,there is little research on this topic,and most of it neglects potential influence factors,leaving the corresponding supporting efficiency questionable.In this paper,we study the landing scheduling problem for carrier aircraft considering the effects of bolting and aerial refueling.Based on the analysis of recovery mode involving the above factors,two types of primary constraints(i.e.,fuel constraint and wake interval constraint)are first described.Then,taking the landing sequencing as decision variables,a combinatorial optimization model with a compound objective function is formulated.Aiming at an efficient solution,an improved firefly algorithm is designed by integrating multiple evolutionary operators.In addition,a dynamic replanning mechanism is introduced to deal with special situations(i.e.,the occurrence of bolting and fuel shortage),where the high efficiency of the designed algorithm facilitates the online scheduling adjustment within seconds.Finally,numerical simulations with sufficient and insufficient fuel cases are both carried out,highlighting the necessity to consider bolting and aerial refueling during the planning procedure.Simulation results reveal that a higher bolting probability,as well as extra aerial refueling operations caused by fuel shortage,will lead to longer recovery complete time.Meanwhile,due to the strong optimum-seeking capability and solution efficiency of the improved algorithm,adaptive scheduling can be generated within milliseconds to deal with special situations,significantly improving the safety and efficiency of the recovery process.An animation is accessible at bilibili.com/video/BV1QprKY2EwD.
基金This work was supported in part by the National Natural Science Foundation of China(Grant No.90820302)the Research Fund for the Doctoral Program of Higher Education(No.200805330005)Hunan S&T Funds(No.06IJY3035).
文摘Multi-robot mission planning is composed of assignment allocation and mobile-robot route planning in this paper.Multi-robot exploration missions adopts fuzzy c-mean(FCM)algorithm to allocate,and then,heterogeneous interactive cultural hybrid algorithm(HICHA)is devised for route planning in order to optimize mobilerobot execution path.Meanwhile,we design multi-robot mission replanning mechanism based on the rules system of greedy algorithm for dynamic stochastic increment missions.Finally,extensive simulation experiments were shown that FCM for assignment allocation and HICHA for route planning were efficacious for mobile-robot exploration mission planning.Furthermore,the improved greedy algorithm based on experience rules met dynamic stochastic increment missions replanning requirement for load balance.
基金Item Sponsored by High Technology Research and Development Program of China(2007AA04Z161)National Natural Science Foundation of China(50574110,50174061)Key Projects of Chongqing Science and Technology Research Projects(CSTC2011AB3053)
文摘A production planning system is designed for the whole steelmaking process, which includes desulfurization, vanadium extraction, steelmaking and continuous casting processes of Panzhihua Iron and Steel Corporation. The system is composed of modeling module, data interface module, data analysis module, static planning module, re-planning module, plan evaluation module, plan simulation module and human-computer interaction module. The system is connected with the L3 system of steel plant by using the data interface module, which can receive the real time scheduling information to make the static plan and re-plan under production disturbances. The simulation and plan evaluation function of the system can assist decision-maker to check and modify the production plan. The simulation experiments with real process data show that the system can make a feasible, executable, and effective production plan, and deal with primary random disturbances during production process timely.
文摘Breast cancer is the most frequent cancer among females and also a leading cause of cancer related mortality worldwide.A multimodality treatment approach may be utilized for optimal management of patients with combinations of surgery,radiation therapy(RT)and systemic treatment.RT composes an integral part of breast conserving treatment,and is typically used after breast conserving surgery to improve local control.Recent years have witnessed significant improvements in the discipline of radiation oncology which allow for more focused and precise treatment delivery.Adaptive radiation therapy(ART)is among the most important RT techniques which may be utilized for redesigning of treatment plans to account for dynamic changes in tumor size and anatomy during the course of irradiation.In the context of breast cancer,ART may serve as an excellent tool for patients receiving breast irradiation followed by a sequential boost to the tumor bed.Primary benefits of ART include more precise boost localization and potential for improved normal tissue sparing with adapted boost target volumes particularly in the setting of seroma reduction during the course of irradiation.Herein,we provide a concise review of ART for breast cancer in light of the literature.
基金Sponsored by the Key Programs of National Natural Science Foundation of China(Grant No.60736025 and 60905056)the Major Programs of China National Space Administration(Grant No.D2120060013)
文摘For autonomous MUAV,the Ground Control Station(GCS)including hardware and modular software programming such as control modular,navigation modular,display modular and monitor modular becomes important equipment to be developed.This paper emphasizes the global planning and the local replanning arithmetic based on three-dimensional velocity potential field for the moving threats.During the test on the ground and in the sky,GCS show the remote sensing information precisely and send the control command in time.The system can be used to assist in the function of autonomous complex task for MUAV.
文摘The design of universal segments and deviation control of segment assembly are essential for robust and low-risk tunnel construction.A building information modeling(BIM)-based framework was proposed for parametric modeling,automatic assembly,and deviation control of universal segments.First,segment models of different levels of detail(LoDs)were built based on BIM visual programming language(VPL)for different project life cycles.Then,the geometric constraints,requirements,and procedures for parametric segment assembly were distilled to develop a program that combines a novel typesetting algorithm with a 3D path replanning algorithm.Typesetting is implemented by introducing a point indication matrix,characterizing segments by sides,and manipulating geometries in a VPL.Simultaneously,3D path replanning,with non-uniform rational B-splines(NURBS)and arcs as basic shapes,was used to resolve unacceptable deviation situations after typesetting.Finally,the proposed framework was validated on a water diversion line and was found to be more effective and accurate than the previous method.
