KD(D&K) (Synthesized Knowledge Discovery System based on Database and KnowledgeBase Cooperating Mechanism) is first advanced in this paper on the basis of KDD (KnowledgeDiscovery System based on Database) and KDK ...KD(D&K) (Synthesized Knowledge Discovery System based on Database and KnowledgeBase Cooperating Mechanism) is first advanced in this paper on the basis of KDD (KnowledgeDiscovery System based on Database) and KDK (Knowledge Discovery System based on KnowledgeBase). KD (D&K) is not simple addition of KDD and KDK but a new system with absolutelynew character and essential development, which is distinct from KDD and KDK and includes them.Not only the generalized structural frame of control rules KD (D&K) acquiring method is proposed,but also the theoretical basis of its key technical problem--don ble-bases cooperating mechanism isdiscussed according to the original academic idea to restrict KDD by basic knowledge base.展开更多
On the basis of KDD(Knowledge Discovery based on Database), this paper proposesthe general framework of open KDD system, discusses its theoretical foundation and realization of technology of its key technology-double ...On the basis of KDD(Knowledge Discovery based on Database), this paper proposesthe general framework of open KDD system, discusses its theoretical foundation and realization of technology of its key technology-double base cooperating mechanism, and especially introduces themining method of cause-and-effect rule. The result of initial illustration shows that the structure ofKDD is effective and available.展开更多
The asymptotic behavior of the time-dependent solution for a 3-species cooperating model was investigated with the effects of both diffusion and time delay taken into consideration. We proved the global asymptotic sta...The asymptotic behavior of the time-dependent solution for a 3-species cooperating model was investigated with the effects of both diffusion and time delay taken into consideration. We proved the global asymptotic stability of a positive steady-state solution to the model problem by using coupled upper and lower solutions for a more general reaction-diffusion system that gives a common framework for 3-species cooperating model problems. The result of global asymptotic stability implies that the model system coexistence is permanent. Some global asymptotic stability results for 2-species cooperating reaction-diffusion systems are included in the discussion, and some known results are extended.展开更多
The Beijing American Allied Signal Inc. Auto Division announced in Beijing in June that it will invest about US$100 million in expanding cooperation with China’s auto industry. Allied Signal Inc. is a leading manufac...The Beijing American Allied Signal Inc. Auto Division announced in Beijing in June that it will invest about US$100 million in expanding cooperation with China’s auto industry. Allied Signal Inc. is a leading manufacturer providing worldwide service in aero-space, auto, chemicals,展开更多
This paper presents a real-time, dynamic system that uses high resolution gimbals and motorized lenses with position encoders on their zoom and focus elements to “recalibrate” the system as needed to track a target....This paper presents a real-time, dynamic system that uses high resolution gimbals and motorized lenses with position encoders on their zoom and focus elements to “recalibrate” the system as needed to track a target. Systems that initially calibrate for a mapping between pixels of a wide field of view (FOV) master camera and the pan-tilt (PT) settings of a steerable narrow FOV slave camera assume that the target is travelling on a plane. As the target travels through the FOV of the master camera, the slave cameras PT settings are then adjusted to keep the target centered within its FOV. In this paper, we describe a system we have developed that allows both cameras to move and extract the 3D coordinates of the target. This is done with only a single initial calibration between pairs of cameras and high-resolution pan-tilt-zoom (PTZ) platforms. Using the information from the PT settings of the PTZ platform as well as the precalibrated settings from a preset zoom lens, the 3D coordinates of the target are extracted and compared to those of a laser range finder and static-dynamic camera pair accuracies.展开更多
For the situation of multiple cooperating manipulators handling a single object,an equilibrium equation is presented in which the manipulator dynamics and control forces/torques are taken into account,and a expression...For the situation of multiple cooperating manipulators handling a single object,an equilibrium equation is presented in which the manipulator dynamics and control forces/torques are taken into account,and a expression is derived to allow the optimal dynamic load distribution of the combined system can be made.展开更多
A novel unified method for computing the dynamic load carrying capacity(DLCC) of multiple cooperating robotic manipulators is developed.In this method,the kinematic constraints and the governing dynamic equations of ...A novel unified method for computing the dynamic load carrying capacity(DLCC) of multiple cooperating robotic manipulators is developed.In this method,the kinematic constraints and the governing dynamic equations of the multiple robot system are formulated in the joint space by using the method of transference of dependence from one set of generalized coordinates to another,and the virtual work principle,which includes the readily available dynamics and joint torques of individual manipulators,and the dynamic of payload.Based on this dynamic model,the upper limit of the DLCC at any points on a given trajectory is obtained by solving a small size linear programming problem.This method is conceptually straightforward,and it is applicable also to the cases of multi fingered robot hands and multi legged walking machines.展开更多
Cell adhesion plays pivotal roles in the morphogenesis of multicellular organisms.Epithelial cells form several types of cell-to-cell adhesion,including zonula occludens(tight junctions),zonula adhaerens(adherens junc...Cell adhesion plays pivotal roles in the morphogenesis of multicellular organisms.Epithelial cells form several types of cell-to-cell adhesion,including zonula occludens(tight junctions),zonula adhaerens(adherens junctions),and macula adhaerens(desmosomes).Although these adhesion complexes are basically observed only in epithelial cells,cadherins,which are the major cell adhesion molecules of adherens junctions,are expressed in both epithelial and non-epithelial tissues,including neural tissues(Kawauchi,2012).The cadherin superfamily consists of more than 100 members,but classic cadherins.展开更多
BACKGROUND Diabetic foot ulcers(DFUs)are a significant contributor to disability and mortality in diabetic patients.Macrophage polarization and functional regulation are promising areas of research and show therapeuti...BACKGROUND Diabetic foot ulcers(DFUs)are a significant contributor to disability and mortality in diabetic patients.Macrophage polarization and functional regulation are promising areas of research and show therapeutic potential in the field of DFU healing.However,the complex mechanism,the difficulty in clinical translation,and the large heterogeneity present significant challenges.Hence,this study was to comprehensively analyze the publication status and trends of studies on macrophage polarization and DFU healing.AIM To examine the relevant literature on macrophage polarization in DFU healing.METHODS A bibliometric analysis was conducted using the Web of Science database.Relevant literature was retrieved from the Web of Science Core Collection database between 2013 to 2023 using literature visualization and analysis software(VOSviewer and CiteSpace)and bibliometric online platforms.The obtained literature was then subjected to visualization and analysis of different countries/regions,institutions,journals,authors,and keywords to reveal the research’s major trends and focus.RESULTS The number of publications on the role of macrophage polarization in DFU healing increased rapidly from 2013 to 2023,especially in the latter period.Chinese researchers were the most prolific in this field,with 217 publications,while American researchers had been engaged in this field for a longer period.Qian Tan of Nanjing Drum Tower Hospital and Qian Ding of Nanjing University were the first to publish in this field.Shanghai Jiao Tong University was the institution with the most publications(27).The keywords“bone marrow”,“adjustment,replacement,response,tissue repair”,and“activation,repair,differentiation”appeared more frequently.The study of macrophage polarization in DFU healing focused on the regulatory mechanism,gene expression,and other aspects.CONCLUSION This study through the bibliometric method reveals the research trends and development trends in this field of macrophage polarization in DFU healing from 2013 to 2023 in the Web of Science Core Collection database.The key hotspots in this field mainly include the regulation of macrophage activation,gene expression,wound tissue repair,and new wound materials.This study provides references for future research directions.展开更多
On June 15,2001, the Declaration on the Establishment of the Shanghai Cooperation Organization was signed, marking the formal launch of the regional organization. Its history can be traced back to 19% when Russia, Chi...On June 15,2001, the Declaration on the Establishment of the Shanghai Cooperation Organization was signed, marking the formal launch of the regional organization. Its history can be traced back to 19% when Russia, China, Kazakhstan, Kyrgyzstan and Tajikistan formed the Shanghai Five, later renamed the Shanghai Forum. After Uzbekistan joined, the forum changed展开更多
China is a large country, whereas Slovakia is a small country.This is something that Slovakia's Ambassador to China Zigmund Bertok repeatedly mentioned in an exclusive interview with Beijing Review reporter Yan We...China is a large country, whereas Slovakia is a small country.This is something that Slovakia's Ambassador to China Zigmund Bertok repeatedly mentioned in an exclusive interview with Beijing Review reporter Yan Wei shortly after Slovak Prime Minister Robert Fico’s official visit to China.Despite the sharp contrast in their geographical size, the two countries are enjoying a fruitful cooperation that is, in the words of the ambassador, "appropriate for their positions."The following are excerpts of the interview:展开更多
The year 2011 marks the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip again boo...The year 2011 marks the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip again boosted burgeoning China-Africa ties, said Chinese Vice Foreign Minister Zhai Jun.展开更多
Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical cha...Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical challenge in accomplishing automated vehicle platoons is to deal with the effects of intermittent and sporadic vehicle-to-vehicle data transmissions caused by limited wireless communication resources. This paper addresses the co-design problem of dynamic event-triggered communication scheduling and cooperative adaptive cruise control for a convoy of automated vehicles with diverse spacing policies. The central aim is to achieve automated vehicle platooning under various gap references with desired platoon stability and spacing performance requirements, while simultaneously improving communication efficiency. Toward this aim, a dynamic event-triggered scheduling mechanism is developed such that the intervehicle data transmissions are scheduled dynamically and efficiently over time. Then, a tractable co-design criterion on the existence of both the admissible event-driven cooperative adaptive cruise control law and the desired scheduling mechanism is derived. Finally, comparative simulation results are presented to substantiate the effectiveness and merits of the obtained results.展开更多
Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is indispensable.However,due to the lack of customized coordination methods,cooperation in the do...Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is indispensable.However,due to the lack of customized coordination methods,cooperation in the downstream oil supply chain cannot be carried out smoothly.This paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation,oil substitution and pipeline pricing schemes.An integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply chain.The proposed mixed integer nonlinear programming model constrains supply and demand capacity,transportation routes,oil substitution rules and pipeline freight levels.Logarithm transformation and price discretization are introduced for model linear approximation.Simulation experiments are carried out in the oil distribution system in South China.The results show that compared to the business-as-usual scheme,the new scheme saves transportation cost by 3.48%,increases pipeline turnover by 5.7%,and reduces energy consumption and emissions by 7.66%and 6.77%.It is proved that the proposed method improves the revenue of the whole system,achieves fair revenue distribution,and also improves the energy and environmental benefits of the oil supply chain.展开更多
Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research pr...Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research problem.In certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable stages.Furthermore,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available stages.Traditional cooperative search algorithms cannot handle such situations well.To solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety factor.An attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision planning.The search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum extent.Simulation results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios.展开更多
To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference a...To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference and external malicious jamming. A cooperative anti-jamming and interference mitigation method based on local altruistic is proposed to optimize UAVs’ channel selection. Specifically, a Stackelberg game is modeled to formulate the confrontation relationship between UAVs and the jammer. A local altruistic game is modeled with each UAV considering the utilities of both itself and other UAVs. A distributed cooperative anti-jamming and interference mitigation algorithm is proposed to obtain the Stackelberg equilibrium. Finally, the convergence of the proposed algorithm and the impact of the transmission power on the system loss value are analyzed, and the anti-jamming performance of the proposed algorithm can be improved by around 64% compared with the existing algorithms.展开更多
This article investigates the problem of robust adaptive leaderless consensus for heterogeneous uncertain nonminimumphase linear multi-agent systems over directed communication graphs. Each agent is assumed tobe of un...This article investigates the problem of robust adaptive leaderless consensus for heterogeneous uncertain nonminimumphase linear multi-agent systems over directed communication graphs. Each agent is assumed tobe of unknown nominal dynamics and also subject to external disturbances and/or unmodeled dynamics. Anovel distributed robust adaptive control strategy is proposed. It is shown that the robust adaptive leaderlessconsensus problem is solved with the proposed control strategy under some sufficient conditions. Two examplesare provided to demonstrate the efficacy of the proposed control strategy.展开更多
Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning(MADRL) is proposed. In this method, an improved Comm Net...Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning(MADRL) is proposed. In this method, an improved Comm Net network based on a communication mechanism is introduced into a deep reinforcement learning algorithm to solve the multi-agent problem. A layer of gated recurrent unit(GRU) is added to the actor-network structure to remember historical environmental states. Subsequently,another GRU is designed as a communication channel in the Comm Net core network layer to refine communication information between UAVs. Finally, the simulation results of the algorithm in two sets of scenarios are given, and the results show that the method has good effectiveness and applicability.展开更多
文摘KD(D&K) (Synthesized Knowledge Discovery System based on Database and KnowledgeBase Cooperating Mechanism) is first advanced in this paper on the basis of KDD (KnowledgeDiscovery System based on Database) and KDK (Knowledge Discovery System based on KnowledgeBase). KD (D&K) is not simple addition of KDD and KDK but a new system with absolutelynew character and essential development, which is distinct from KDD and KDK and includes them.Not only the generalized structural frame of control rules KD (D&K) acquiring method is proposed,but also the theoretical basis of its key technical problem--don ble-bases cooperating mechanism isdiscussed according to the original academic idea to restrict KDD by basic knowledge base.
文摘On the basis of KDD(Knowledge Discovery based on Database), this paper proposesthe general framework of open KDD system, discusses its theoretical foundation and realization of technology of its key technology-double base cooperating mechanism, and especially introduces themining method of cause-and-effect rule. The result of initial illustration shows that the structure ofKDD is effective and available.
基金the Academic Mainstay Cultivate Foundation of Sichuan Province under the grant No.1200311.
文摘The asymptotic behavior of the time-dependent solution for a 3-species cooperating model was investigated with the effects of both diffusion and time delay taken into consideration. We proved the global asymptotic stability of a positive steady-state solution to the model problem by using coupled upper and lower solutions for a more general reaction-diffusion system that gives a common framework for 3-species cooperating model problems. The result of global asymptotic stability implies that the model system coexistence is permanent. Some global asymptotic stability results for 2-species cooperating reaction-diffusion systems are included in the discussion, and some known results are extended.
文摘The Beijing American Allied Signal Inc. Auto Division announced in Beijing in June that it will invest about US$100 million in expanding cooperation with China’s auto industry. Allied Signal Inc. is a leading manufacturer providing worldwide service in aero-space, auto, chemicals,
文摘This paper presents a real-time, dynamic system that uses high resolution gimbals and motorized lenses with position encoders on their zoom and focus elements to “recalibrate” the system as needed to track a target. Systems that initially calibrate for a mapping between pixels of a wide field of view (FOV) master camera and the pan-tilt (PT) settings of a steerable narrow FOV slave camera assume that the target is travelling on a plane. As the target travels through the FOV of the master camera, the slave cameras PT settings are then adjusted to keep the target centered within its FOV. In this paper, we describe a system we have developed that allows both cameras to move and extract the 3D coordinates of the target. This is done with only a single initial calibration between pairs of cameras and high-resolution pan-tilt-zoom (PTZ) platforms. Using the information from the PT settings of the PTZ platform as well as the precalibrated settings from a preset zoom lens, the 3D coordinates of the target are extracted and compared to those of a laser range finder and static-dynamic camera pair accuracies.
文摘For the situation of multiple cooperating manipulators handling a single object,an equilibrium equation is presented in which the manipulator dynamics and control forces/torques are taken into account,and a expression is derived to allow the optimal dynamic load distribution of the combined system can be made.
文摘A novel unified method for computing the dynamic load carrying capacity(DLCC) of multiple cooperating robotic manipulators is developed.In this method,the kinematic constraints and the governing dynamic equations of the multiple robot system are formulated in the joint space by using the method of transference of dependence from one set of generalized coordinates to another,and the virtual work principle,which includes the readily available dynamics and joint torques of individual manipulators,and the dynamic of payload.Based on this dynamic model,the upper limit of the DLCC at any points on a given trajectory is obtained by solving a small size linear programming problem.This method is conceptually straightforward,and it is applicable also to the cases of multi fingered robot hands and multi legged walking machines.
基金funded by JSPS KAKENHI Grant Numbers JP26290015 and JP21H02655(to TK)from Ministry of Education,Culture,Sports,Science,and Technology of Japan(MEXT)。
文摘Cell adhesion plays pivotal roles in the morphogenesis of multicellular organisms.Epithelial cells form several types of cell-to-cell adhesion,including zonula occludens(tight junctions),zonula adhaerens(adherens junctions),and macula adhaerens(desmosomes).Although these adhesion complexes are basically observed only in epithelial cells,cadherins,which are the major cell adhesion molecules of adherens junctions,are expressed in both epithelial and non-epithelial tissues,including neural tissues(Kawauchi,2012).The cadherin superfamily consists of more than 100 members,but classic cadherins.
基金Supported by the Qilu Medical School Traditional Chinese Medicine Academic School Inheritance Project,No.93 LW[2022]Construction Project of the Inheritance Studio of National Famous Traditional Chinese Medicine Experts,Traditional Chinese Medicine Teaching Letter No.75[2022]Qilu Health and Fitness Talents in 2019,No.3 LWRZ[2020].
文摘BACKGROUND Diabetic foot ulcers(DFUs)are a significant contributor to disability and mortality in diabetic patients.Macrophage polarization and functional regulation are promising areas of research and show therapeutic potential in the field of DFU healing.However,the complex mechanism,the difficulty in clinical translation,and the large heterogeneity present significant challenges.Hence,this study was to comprehensively analyze the publication status and trends of studies on macrophage polarization and DFU healing.AIM To examine the relevant literature on macrophage polarization in DFU healing.METHODS A bibliometric analysis was conducted using the Web of Science database.Relevant literature was retrieved from the Web of Science Core Collection database between 2013 to 2023 using literature visualization and analysis software(VOSviewer and CiteSpace)and bibliometric online platforms.The obtained literature was then subjected to visualization and analysis of different countries/regions,institutions,journals,authors,and keywords to reveal the research’s major trends and focus.RESULTS The number of publications on the role of macrophage polarization in DFU healing increased rapidly from 2013 to 2023,especially in the latter period.Chinese researchers were the most prolific in this field,with 217 publications,while American researchers had been engaged in this field for a longer period.Qian Tan of Nanjing Drum Tower Hospital and Qian Ding of Nanjing University were the first to publish in this field.Shanghai Jiao Tong University was the institution with the most publications(27).The keywords“bone marrow”,“adjustment,replacement,response,tissue repair”,and“activation,repair,differentiation”appeared more frequently.The study of macrophage polarization in DFU healing focused on the regulatory mechanism,gene expression,and other aspects.CONCLUSION This study through the bibliometric method reveals the research trends and development trends in this field of macrophage polarization in DFU healing from 2013 to 2023 in the Web of Science Core Collection database.The key hotspots in this field mainly include the regulation of macrophage activation,gene expression,wound tissue repair,and new wound materials.This study provides references for future research directions.
文摘The Shanghai Cooperation Organization provides economic and strategic benefits to its members since its establishment in 2001,the Shanghai Cooperation
文摘On June 15,2001, the Declaration on the Establishment of the Shanghai Cooperation Organization was signed, marking the formal launch of the regional organization. Its history can be traced back to 19% when Russia, China, Kazakhstan, Kyrgyzstan and Tajikistan formed the Shanghai Five, later renamed the Shanghai Forum. After Uzbekistan joined, the forum changed
文摘China is a large country, whereas Slovakia is a small country.This is something that Slovakia's Ambassador to China Zigmund Bertok repeatedly mentioned in an exclusive interview with Beijing Review reporter Yan Wei shortly after Slovak Prime Minister Robert Fico’s official visit to China.Despite the sharp contrast in their geographical size, the two countries are enjoying a fruitful cooperation that is, in the words of the ambassador, "appropriate for their positions."The following are excerpts of the interview:
文摘The year 2011 marks the 55th anniversary of the start of contemporary friendly relations between the People’s Republic of China and African countries. Chinese Vice Premier Hui Liangyu’s recent African trip again boosted burgeoning China-Africa ties, said Chinese Vice Foreign Minister Zhai Jun.
基金supported in part by the Australian Research Council Discovery Early Career Researcher Award(DE200101128)。
文摘Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical challenge in accomplishing automated vehicle platoons is to deal with the effects of intermittent and sporadic vehicle-to-vehicle data transmissions caused by limited wireless communication resources. This paper addresses the co-design problem of dynamic event-triggered communication scheduling and cooperative adaptive cruise control for a convoy of automated vehicles with diverse spacing policies. The central aim is to achieve automated vehicle platooning under various gap references with desired platoon stability and spacing performance requirements, while simultaneously improving communication efficiency. Toward this aim, a dynamic event-triggered scheduling mechanism is developed such that the intervehicle data transmissions are scheduled dynamically and efficiently over time. Then, a tractable co-design criterion on the existence of both the admissible event-driven cooperative adaptive cruise control law and the desired scheduling mechanism is derived. Finally, comparative simulation results are presented to substantiate the effectiveness and merits of the obtained results.
基金partially supported by the Science Foundation of China University of Petroleum,Beijing(2462023XKBH013)the National Natural Science Foundation of China(52202405)。
文摘Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is indispensable.However,due to the lack of customized coordination methods,cooperation in the downstream oil supply chain cannot be carried out smoothly.This paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation,oil substitution and pipeline pricing schemes.An integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply chain.The proposed mixed integer nonlinear programming model constrains supply and demand capacity,transportation routes,oil substitution rules and pipeline freight levels.Logarithm transformation and price discretization are introduced for model linear approximation.Simulation experiments are carried out in the oil distribution system in South China.The results show that compared to the business-as-usual scheme,the new scheme saves transportation cost by 3.48%,increases pipeline turnover by 5.7%,and reduces energy consumption and emissions by 7.66%and 6.77%.It is proved that the proposed method improves the revenue of the whole system,achieves fair revenue distribution,and also improves the energy and environmental benefits of the oil supply chain.
基金the support of the National Natural Science Foundation of China(Grant No.62076204)the Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University(Grant No.CX2020019)in part by the China Postdoctoral Science Foundation(Grants No.2021M700337)。
文摘Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research problem.In certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable stages.Furthermore,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available stages.Traditional cooperative search algorithms cannot handle such situations well.To solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety factor.An attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision planning.The search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum extent.Simulation results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios.
基金supported in part by the National Natural Science Foundation of China (No.62271253,61901523,62001381)Fundamental Research Funds for the Central Universities (No.NS2023018)+2 种基金the National Aerospace Science Foundation of China under Grant 2023Z021052002the open research fund of National Mobile Communications Research Laboratory,Southeast University (No.2023D09)Postgraduate Research & Practice Innovation Program of NUAA (No.xcxjh20220402)。
文摘To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference and external malicious jamming. A cooperative anti-jamming and interference mitigation method based on local altruistic is proposed to optimize UAVs’ channel selection. Specifically, a Stackelberg game is modeled to formulate the confrontation relationship between UAVs and the jammer. A local altruistic game is modeled with each UAV considering the utilities of both itself and other UAVs. A distributed cooperative anti-jamming and interference mitigation algorithm is proposed to obtain the Stackelberg equilibrium. Finally, the convergence of the proposed algorithm and the impact of the transmission power on the system loss value are analyzed, and the anti-jamming performance of the proposed algorithm can be improved by around 64% compared with the existing algorithms.
基金Research Grants Council of Hong Kong under Grant CityU-11205221.
文摘This article investigates the problem of robust adaptive leaderless consensus for heterogeneous uncertain nonminimumphase linear multi-agent systems over directed communication graphs. Each agent is assumed tobe of unknown nominal dynamics and also subject to external disturbances and/or unmodeled dynamics. Anovel distributed robust adaptive control strategy is proposed. It is shown that the robust adaptive leaderlessconsensus problem is solved with the proposed control strategy under some sufficient conditions. Two examplesare provided to demonstrate the efficacy of the proposed control strategy.
基金supported in part by the National Key Laboratory of Air-based Information Perception and Fusion and the Aeronautical Science Foundation of China (Grant No. 20220001068001)National Natural Science Foundation of China (Grant No.61673327)+1 种基金Natural Science Basic Research Plan in Shaanxi Province,China (Grant No. 2023-JC-QN-0733)China IndustryUniversity-Research Innovation Foundation (Grant No. 2022IT188)。
文摘Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning(MADRL) is proposed. In this method, an improved Comm Net network based on a communication mechanism is introduced into a deep reinforcement learning algorithm to solve the multi-agent problem. A layer of gated recurrent unit(GRU) is added to the actor-network structure to remember historical environmental states. Subsequently,another GRU is designed as a communication channel in the Comm Net core network layer to refine communication information between UAVs. Finally, the simulation results of the algorithm in two sets of scenarios are given, and the results show that the method has good effectiveness and applicability.