With the development of high energy solid propellants,it is critical to evaluate the safety and power performance of solid propellants in the face of threats such as unmanned aerial vehicles(UAVs)when transporting and...With the development of high energy solid propellants,it is critical to evaluate the safety and power performance of solid propellants in the face of threats such as unmanned aerial vehicles(UAVs)when transporting and using them in contemporary warfare.An electric probe-type cylinder test measured the displacement-time behavior of NEPE high-energy solid propellant,and the parameters of the Jones-Wilkins-Lee(JWL)equation of state(EOS)were derived using particle swarm optimization(PSO)with the Gurney energy model.Further,the parameters of JWL-Miller EOS,determined through AUTODYN simulations,were validated by comparing airburst process simulations with experimental overpressure data.The study established a method for determining EOS parameters of high-energy propellants,achieving a high degree of accuracy.The derived parameters ensure precise modeling of propellant behavior,offering a reliable foundation for future applications in solid rocket motor performance optimization and safety assessment.展开更多
When the maneuverability of a pursuer is not significantly higher than that of an evader,it will be difficult to intercept the evader with only one pursuer.Therefore,this article adopts a two-to-one differential game ...When the maneuverability of a pursuer is not significantly higher than that of an evader,it will be difficult to intercept the evader with only one pursuer.Therefore,this article adopts a two-to-one differential game strategy,the game of kind is generally considered to be angle-optimized,which allows unlimited turns,but these practices do not take into account the effect of acceleration,which does not correspond to the actual situation,thus,based on the angle-optimized,the acceleration optimization and the acceleration upper bound constraint are added into the game for consideration.A two-to-one differential game problem is proposed in the three-dimensional space,and an improved multi-objective grey wolf optimization(IMOGWO)algorithm is proposed to solve the optimal game point of this problem.With the equations that describe the relative motions between the pursuers and the evader in the three-dimensional space,a multi-objective function with constraints is given as the performance index to design an optimal strategy for the differential game.Then the optimal game point is solved by using the IMOGWO algorithm.It is proved based on Markov chains that with the IMOGWO,the Pareto solution set is the solution of the differential game.Finally,it is verified through simulations that the pursuers can capture the escapee,and via comparative experiments,it is shown that the IMOGWO algorithm performs well in terms of running time and memory usage.展开更多
In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of t...In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of the three-dimensional attack area model,restrict their practical applications.To address these issues,an improved backtracking algorithm is proposed to improve calculation efficiency.A significant reduction in solution time and maintenance of accuracy in the three-dimensional attack area are achieved by using the proposed algorithm.Furthermore,the age-layered population structure genetic programming(ALPS-GP)algorithm is introduced to determine an analytical polynomial model of the three-dimensional attack area,considering real-time requirements.The accuracy of the polynomial model is enhanced through the coefficient correction using an improved gradient descent algorithm.The study reveals a remarkable combination of high accuracy and efficient real-time computation,with a mean error of 91.89 m using the analytical polynomial model of the three-dimensional attack area solved in just 10^(-4)s,thus meeting the requirements of real-time combat scenarios.展开更多
Offboard active decoys(OADs)can effectively jam monopulse radars.However,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for t...Offboard active decoys(OADs)can effectively jam monopulse radars.However,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for timing and deployment.To improve the response speed and jamming effect,a cluster of OADs based on an unmanned surface vehicle(USV)is proposed.The formation of the cluster determines the effectiveness of jamming.First,based on the mechanism of OAD jamming,critical conditions are identified,and a method for assessing the jamming effect is proposed.Then,for the optimization of the cluster formation,a mathematical model is built,and a multi-tribe adaptive particle swarm optimization algorithm based on mutation strategy and Metropolis criterion(3M-APSO)is designed.Finally,the formation optimization problem is solved and analyzed using the 3M-APSO algorithm under specific scenarios.The results show that the improved algorithm has a faster convergence rate and superior performance as compared to the standard Adaptive-PSO algorithm.Compared with a single OAD,the optimal formation of USV-OAD cluster effectively fills the blind area and maximizes the use of jamming resources.展开更多
为加快末端物流配送的效率,提出一种配送无人机的航迹规划问题。针对传统快速搜索随机树(rapidlysearch random tree,RRT)算法在航迹规划中存在的盲目性和路径不平滑等问题,将人工势场法(artificial potential field,APF)与Informed-RRT...为加快末端物流配送的效率,提出一种配送无人机的航迹规划问题。针对传统快速搜索随机树(rapidlysearch random tree,RRT)算法在航迹规划中存在的盲目性和路径不平滑等问题,将人工势场法(artificial potential field,APF)与Informed-RRT^(*)算法融合,提出一种自适应步长增长策略的改进APF-Informed-RRT^(*)算法。首先在选择新节点时,考虑到障碍物和目标点的影响,提出一种自适应步长增长策略来解决采样的盲目性;其次采用三次B样条对拐点处进行平滑处理;最后分别采用RRT^(*)算法、Informed-RRT^(*)算法和改进APF-Informed-RRT^(*)算法在两种环境中进行仿真实验。结果表明,改进APF-Informed-RRT^(*)算法相较于RRT^(*)算法和Informed-RRT^(*)算法,在运行时间、迭代次数以及路径平滑上都得到提升。展开更多
[Objective]Real-time monitoring of cow ruminant behavior is of paramount importance for promptly obtaining relevant information about cow health and predicting cow diseases.Currently,various strategies have been propo...[Objective]Real-time monitoring of cow ruminant behavior is of paramount importance for promptly obtaining relevant information about cow health and predicting cow diseases.Currently,various strategies have been proposed for monitoring cow ruminant behavior,including video surveillance,sound recognition,and sensor monitoring methods.How‐ever,the application of edge device gives rise to the issue of inadequate real-time performance.To reduce the volume of data transmission and cloud computing workload while achieving real-time monitoring of dairy cow rumination behavior,a real-time monitoring method was proposed for cow ruminant behavior based on edge computing.[Methods]Autono‐mously designed edge devices were utilized to collect and process six-axis acceleration signals from cows in real-time.Based on these six-axis data,two distinct strategies,federated edge intelligence and split edge intelligence,were investigat‐ed for the real-time recognition of cow ruminant behavior.Focused on the real-time recognition method for cow ruminant behavior leveraging federated edge intelligence,the CA-MobileNet v3 network was proposed by enhancing the MobileNet v3 network with a collaborative attention mechanism.Additionally,a federated edge intelligence model was designed uti‐lizing the CA-MobileNet v3 network and the FedAvg federated aggregation algorithm.In the study on split edge intelli‐gence,a split edge intelligence model named MobileNet-LSTM was designed by integrating the MobileNet v3 network with a fusion collaborative attention mechanism and the Bi-LSTM network.[Results and Discussions]Through compara‐tive experiments with MobileNet v3 and MobileNet-LSTM,the federated edge intelligence model based on CA-Mo‐bileNet v3 achieved an average Precision rate,Recall rate,F1-Score,Specificity,and Accuracy of 97.1%,97.9%,97.5%,98.3%,and 98.2%,respectively,yielding the best recognition performance.[Conclusions]It is provided a real-time and effective method for monitoring cow ruminant behavior,and the proposed federated edge intelligence model can be ap‐plied in practical settings.展开更多
Nitrogen(N)and phosphorus(P)are mineral nutrients essential for plant growth and development,playing a crucial role throughout the plant life cycle.Cotton,a globally significant textile crop,has a particularly high de...Nitrogen(N)and phosphorus(P)are mineral nutrients essential for plant growth and development,playing a crucial role throughout the plant life cycle.Cotton,a globally significant textile crop,has a particularly high demand for N fertilizer across its developmental stages.This review explores the effects of adequate or deficient N and P levels on cotton growth phases,focusing on their influence on physiological processes and molecular mechanisms.Key topics include the regulation of N-and P-related enzymes,hormones,and genes,as well as the complex interplay of N-and P-related signaling pathways from the aspects of N-P signaling integration to regulate root development,N-P signaling integration to regulate nutrient uptake,and regulation of N-P interactions—a frontier in current research.Strategies for improving N and P use efficiency are also discussed,including developing high-efficiency cotton cultivars and identifying functional genes to enhance productivity.Generally speaking,we take model plants as a reference in the hope of coming up with new strategies for the efficient utilization of N and P in cotton.展开更多
针对舰载机甲板路径规划问题,在Informed-RRT^(*)(informed rapidly-exploring random tree)的椭圆采样基础上,提出使用正态分布方式采样的IN-RRT^(*)(informed normal-RRT^(*))算法。首先,针对舰载机与运动场景建模,定义舰载机运动约...针对舰载机甲板路径规划问题,在Informed-RRT^(*)(informed rapidly-exploring random tree)的椭圆采样基础上,提出使用正态分布方式采样的IN-RRT^(*)(informed normal-RRT^(*))算法。首先,针对舰载机与运动场景建模,定义舰载机运动约束和避障策略;其次,将正态分布采样策略与椭圆采样相结合,获取优质高效采样点;引入人工势场法,自适应调节随机树的搜索步长值;使用向心Catmull-Rom样条插值法对路径进行平滑优化处理;提出针对动态障碍改进的动态窗口法,实现局部动态避障。最后,运用甲板平面环境实验检验算法性能。结果表明,IN-RRT^(*)算法能显著优化搜索时间和搜索路径质量,可应对动态场景规划出合理可行的平滑路径。展开更多
P code direct acquisition is an important technology in satellite navigation system. As the P code has a long period, it is hard to directly acquire. The traditional average method can process multiple code phases in ...P code direct acquisition is an important technology in satellite navigation system. As the P code has a long period, it is hard to directly acquire. The traditional average method can process multiple code phases in a time to shorten the acquisition time. But with the increase of average phase error of the input signal and the local code, the correlation signal-to-noise ratio (SNR) loss increases. To reduce the SNR loss, an improved average method is introduced. A new sequence is generated with a summation of phase shifting sequences to decrease correlation peak loss. Simulation results show that compared with direct average method, the improved average method effectively increases correlation SNR.展开更多
According to the infrared guidance ammunition(GA)attacking non-maneuvering targets on the ground or sea level,an improved bias proportional navigation(IBPN) is put forward,which can meet the constraints of the impact ...According to the infrared guidance ammunition(GA)attacking non-maneuvering targets on the ground or sea level,an improved bias proportional navigation(IBPN) is put forward,which can meet the constraints of the impact angle and the angle of attack(AOA). The motion equations and the collision triangle for the GA and the target are established in the two-dimensional plane. In accordance with the collision triangle, the integral value of the bias term is solved and BPN is designed on the basis of the relative velocity. To ensure the new method can be solved, closedloop equation of the IBPN is deduced. Considering the limitation of the AOA and the seeker angle, a four-phase IBPN is improved by setting different phases of the bias term. At the same time, the guidance law will make the impact angle achieve the desired angle and the normal acceleration also converges to zero. The simulation results show that the improved guidance law can be applied to various flight tasks and has great potential for engineering applications.展开更多
The cross-efficiency evaluation method is reviewed which is developed as a data envelopment analysis (DEA) extensive tool. The cross-efficiency evaluation method is utilized to identify the decision making unit (DM...The cross-efficiency evaluation method is reviewed which is developed as a data envelopment analysis (DEA) extensive tool. The cross-efficiency evaluation method is utilized to identify the decision making unit (DMU) with the best practice and to rank the DMUs by their respective cross-efficiency scores. The main drawbacks of the cross-efficiency evaluation method when the ultimate average cross-efficiency scores are used to evalu- ate and rank the DMUs are also pointed out. With the research gap, an improved technique for order preference by similarity to ideal solution (TOPSIS) is introduced to rank the crossfficiency by eliminating the average assumption. Finally, an empirical example is illustrated to examine the validity of the proposed method.展开更多
基金supported by"the Fundamental Research Funds for the Central Universities",No.30924010503.
文摘With the development of high energy solid propellants,it is critical to evaluate the safety and power performance of solid propellants in the face of threats such as unmanned aerial vehicles(UAVs)when transporting and using them in contemporary warfare.An electric probe-type cylinder test measured the displacement-time behavior of NEPE high-energy solid propellant,and the parameters of the Jones-Wilkins-Lee(JWL)equation of state(EOS)were derived using particle swarm optimization(PSO)with the Gurney energy model.Further,the parameters of JWL-Miller EOS,determined through AUTODYN simulations,were validated by comparing airburst process simulations with experimental overpressure data.The study established a method for determining EOS parameters of high-energy propellants,achieving a high degree of accuracy.The derived parameters ensure precise modeling of propellant behavior,offering a reliable foundation for future applications in solid rocket motor performance optimization and safety assessment.
基金National Natural Science Foundation of China(NSFC61773142,NSFC62303136)。
文摘When the maneuverability of a pursuer is not significantly higher than that of an evader,it will be difficult to intercept the evader with only one pursuer.Therefore,this article adopts a two-to-one differential game strategy,the game of kind is generally considered to be angle-optimized,which allows unlimited turns,but these practices do not take into account the effect of acceleration,which does not correspond to the actual situation,thus,based on the angle-optimized,the acceleration optimization and the acceleration upper bound constraint are added into the game for consideration.A two-to-one differential game problem is proposed in the three-dimensional space,and an improved multi-objective grey wolf optimization(IMOGWO)algorithm is proposed to solve the optimal game point of this problem.With the equations that describe the relative motions between the pursuers and the evader in the three-dimensional space,a multi-objective function with constraints is given as the performance index to design an optimal strategy for the differential game.Then the optimal game point is solved by using the IMOGWO algorithm.It is proved based on Markov chains that with the IMOGWO,the Pareto solution set is the solution of the differential game.Finally,it is verified through simulations that the pursuers can capture the escapee,and via comparative experiments,it is shown that the IMOGWO algorithm performs well in terms of running time and memory usage.
基金National Natural Science Foundation of China(62373187)Forward-looking Layout Special Projects(ILA220591A22)。
文摘In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of the three-dimensional attack area model,restrict their practical applications.To address these issues,an improved backtracking algorithm is proposed to improve calculation efficiency.A significant reduction in solution time and maintenance of accuracy in the three-dimensional attack area are achieved by using the proposed algorithm.Furthermore,the age-layered population structure genetic programming(ALPS-GP)algorithm is introduced to determine an analytical polynomial model of the three-dimensional attack area,considering real-time requirements.The accuracy of the polynomial model is enhanced through the coefficient correction using an improved gradient descent algorithm.The study reveals a remarkable combination of high accuracy and efficient real-time computation,with a mean error of 91.89 m using the analytical polynomial model of the three-dimensional attack area solved in just 10^(-4)s,thus meeting the requirements of real-time combat scenarios.
基金the National Natural Science Foundation of China(Grant No.62101579).
文摘Offboard active decoys(OADs)can effectively jam monopulse radars.However,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for timing and deployment.To improve the response speed and jamming effect,a cluster of OADs based on an unmanned surface vehicle(USV)is proposed.The formation of the cluster determines the effectiveness of jamming.First,based on the mechanism of OAD jamming,critical conditions are identified,and a method for assessing the jamming effect is proposed.Then,for the optimization of the cluster formation,a mathematical model is built,and a multi-tribe adaptive particle swarm optimization algorithm based on mutation strategy and Metropolis criterion(3M-APSO)is designed.Finally,the formation optimization problem is solved and analyzed using the 3M-APSO algorithm under specific scenarios.The results show that the improved algorithm has a faster convergence rate and superior performance as compared to the standard Adaptive-PSO algorithm.Compared with a single OAD,the optimal formation of USV-OAD cluster effectively fills the blind area and maximizes the use of jamming resources.
文摘为加快末端物流配送的效率,提出一种配送无人机的航迹规划问题。针对传统快速搜索随机树(rapidlysearch random tree,RRT)算法在航迹规划中存在的盲目性和路径不平滑等问题,将人工势场法(artificial potential field,APF)与Informed-RRT^(*)算法融合,提出一种自适应步长增长策略的改进APF-Informed-RRT^(*)算法。首先在选择新节点时,考虑到障碍物和目标点的影响,提出一种自适应步长增长策略来解决采样的盲目性;其次采用三次B样条对拐点处进行平滑处理;最后分别采用RRT^(*)算法、Informed-RRT^(*)算法和改进APF-Informed-RRT^(*)算法在两种环境中进行仿真实验。结果表明,改进APF-Informed-RRT^(*)算法相较于RRT^(*)算法和Informed-RRT^(*)算法,在运行时间、迭代次数以及路径平滑上都得到提升。
文摘[Objective]Real-time monitoring of cow ruminant behavior is of paramount importance for promptly obtaining relevant information about cow health and predicting cow diseases.Currently,various strategies have been proposed for monitoring cow ruminant behavior,including video surveillance,sound recognition,and sensor monitoring methods.How‐ever,the application of edge device gives rise to the issue of inadequate real-time performance.To reduce the volume of data transmission and cloud computing workload while achieving real-time monitoring of dairy cow rumination behavior,a real-time monitoring method was proposed for cow ruminant behavior based on edge computing.[Methods]Autono‐mously designed edge devices were utilized to collect and process six-axis acceleration signals from cows in real-time.Based on these six-axis data,two distinct strategies,federated edge intelligence and split edge intelligence,were investigat‐ed for the real-time recognition of cow ruminant behavior.Focused on the real-time recognition method for cow ruminant behavior leveraging federated edge intelligence,the CA-MobileNet v3 network was proposed by enhancing the MobileNet v3 network with a collaborative attention mechanism.Additionally,a federated edge intelligence model was designed uti‐lizing the CA-MobileNet v3 network and the FedAvg federated aggregation algorithm.In the study on split edge intelli‐gence,a split edge intelligence model named MobileNet-LSTM was designed by integrating the MobileNet v3 network with a fusion collaborative attention mechanism and the Bi-LSTM network.[Results and Discussions]Through compara‐tive experiments with MobileNet v3 and MobileNet-LSTM,the federated edge intelligence model based on CA-Mo‐bileNet v3 achieved an average Precision rate,Recall rate,F1-Score,Specificity,and Accuracy of 97.1%,97.9%,97.5%,98.3%,and 98.2%,respectively,yielding the best recognition performance.[Conclusions]It is provided a real-time and effective method for monitoring cow ruminant behavior,and the proposed federated edge intelligence model can be ap‐plied in practical settings.
基金supported by Supported by National Key Laboratory of Cotton Bio-breeding and Integrated Utilization(CB2023C07)Xinjiang Autonomous Region"Three Agricultural"Backbone Talent Training Program(2022SNGGNT024)Xinjiang Huyanghe City Science and Technology Program(2023C08).
文摘Nitrogen(N)and phosphorus(P)are mineral nutrients essential for plant growth and development,playing a crucial role throughout the plant life cycle.Cotton,a globally significant textile crop,has a particularly high demand for N fertilizer across its developmental stages.This review explores the effects of adequate or deficient N and P levels on cotton growth phases,focusing on their influence on physiological processes and molecular mechanisms.Key topics include the regulation of N-and P-related enzymes,hormones,and genes,as well as the complex interplay of N-and P-related signaling pathways from the aspects of N-P signaling integration to regulate root development,N-P signaling integration to regulate nutrient uptake,and regulation of N-P interactions—a frontier in current research.Strategies for improving N and P use efficiency are also discussed,including developing high-efficiency cotton cultivars and identifying functional genes to enhance productivity.Generally speaking,we take model plants as a reference in the hope of coming up with new strategies for the efficient utilization of N and P in cotton.
文摘针对舰载机甲板路径规划问题,在Informed-RRT^(*)(informed rapidly-exploring random tree)的椭圆采样基础上,提出使用正态分布方式采样的IN-RRT^(*)(informed normal-RRT^(*))算法。首先,针对舰载机与运动场景建模,定义舰载机运动约束和避障策略;其次,将正态分布采样策略与椭圆采样相结合,获取优质高效采样点;引入人工势场法,自适应调节随机树的搜索步长值;使用向心Catmull-Rom样条插值法对路径进行平滑优化处理;提出针对动态障碍改进的动态窗口法,实现局部动态避障。最后,运用甲板平面环境实验检验算法性能。结果表明,IN-RRT^(*)算法能显著优化搜索时间和搜索路径质量,可应对动态场景规划出合理可行的平滑路径。
文摘P code direct acquisition is an important technology in satellite navigation system. As the P code has a long period, it is hard to directly acquire. The traditional average method can process multiple code phases in a time to shorten the acquisition time. But with the increase of average phase error of the input signal and the local code, the correlation signal-to-noise ratio (SNR) loss increases. To reduce the SNR loss, an improved average method is introduced. A new sequence is generated with a summation of phase shifting sequences to decrease correlation peak loss. Simulation results show that compared with direct average method, the improved average method effectively increases correlation SNR.
基金supported by the China Postdoctoral Science Foundation(2013T60923)
文摘According to the infrared guidance ammunition(GA)attacking non-maneuvering targets on the ground or sea level,an improved bias proportional navigation(IBPN) is put forward,which can meet the constraints of the impact angle and the angle of attack(AOA). The motion equations and the collision triangle for the GA and the target are established in the two-dimensional plane. In accordance with the collision triangle, the integral value of the bias term is solved and BPN is designed on the basis of the relative velocity. To ensure the new method can be solved, closedloop equation of the IBPN is deduced. Considering the limitation of the AOA and the seeker angle, a four-phase IBPN is improved by setting different phases of the bias term. At the same time, the guidance law will make the impact angle achieve the desired angle and the normal acceleration also converges to zero. The simulation results show that the improved guidance law can be applied to various flight tasks and has great potential for engineering applications.
基金supported by the National Natural Science Foundation of China for Innovative Research Groups(70821001),the National Natural Science Foundation of China(70901069)the Special Fund for the Gainers of Excellent Ph.D.'s Dissertations and Dean's Scholarships of Chinese Academy of Sciences,the Research Fund for the Doctoral Program of Higher Education of China for New Teachers(20093402120013)+1 种基金the Research Fund for the Excellent Youth Scholars of Higher School of Anhui Province of China(2010SQRW001ZD)the Social Science Research Fund for Higher School of Anhui Province of China
文摘The cross-efficiency evaluation method is reviewed which is developed as a data envelopment analysis (DEA) extensive tool. The cross-efficiency evaluation method is utilized to identify the decision making unit (DMU) with the best practice and to rank the DMUs by their respective cross-efficiency scores. The main drawbacks of the cross-efficiency evaluation method when the ultimate average cross-efficiency scores are used to evalu- ate and rank the DMUs are also pointed out. With the research gap, an improved technique for order preference by similarity to ideal solution (TOPSIS) is introduced to rank the crossfficiency by eliminating the average assumption. Finally, an empirical example is illustrated to examine the validity of the proposed method.