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Research on three-dimensional attack area based on improved backtracking and ALPS-GP algorithms of air-to-air missile
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作者 ZHANG Haodi WANG Yuhui HE Jiale 《Journal of Systems Engineering and Electronics》 2025年第1期292-310,共19页
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
关键词 air combat three-dimensional attack area improved backtracking algorithm age-layered population structure genetic programming(ALPS-GP) gradient descent algorithm
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Optimization of jamming formation of USV offboard active decoy clusters based on an improved PSO algorithm 被引量:1
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作者 Zhaodong Wu Yasong Luo Shengliang Hu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期529-540,共12页
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
关键词 Electronic countermeasure Offboard active decoy USV cluster Jamming formation optimization improved PSO algorithm
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基于改进A^(*)和DWA融合的机器人路径规划
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作者 崔鹏鹏 张梅 周伸伸 《传感器与微系统》 北大核心 2025年第7期144-148,154,共6页
针对传统A^(*)算法在复杂环境中存在的路径冗余、贴近障碍物及动态避障不足等问题,以及动态窗口法(DWA)算法易陷入局部最优、动态响应滞后等问题,本文提出一种改进A^(*)与DWA算法融合的路径规划算法,融合算法将全局路径关键节点与动态... 针对传统A^(*)算法在复杂环境中存在的路径冗余、贴近障碍物及动态避障不足等问题,以及动态窗口法(DWA)算法易陷入局部最优、动态响应滞后等问题,本文提出一种改进A^(*)与DWA算法融合的路径规划算法,融合算法将全局路径关键节点与动态避障结合,兼顾全局最优与动态适应性。在全局规划中,改进A^(*)算法通过自适应评价函数动态调整启发式权重,引入安全距离惩罚项与障碍物密度感知机制,来优化路径安全性与平滑性,并结合线段可达性检测策略消除冗余转折点;在局部规划中,改进DWA算法通过多目标评价函数融合全局路径跟踪、障碍物距离及轨迹平滑性指标,增强避障灵活性与实时性。实验结果表明,该算法在路径全局最优性、动态避障效率及轨迹平滑度方面均表现出显著优势。 展开更多
关键词 机器人路径规划 改进A^(*)算法 改进动态窗口法算法 融合算法 动态避障
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基于改进A^(*)算法的矿用巡检机器人路径规划
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作者 张辉 苏国用 +2 位作者 赵东洋 杨宇豪 何凯 《太原理工大学学报》 北大核心 2025年第3期559-566,共8页
【目的】针对煤矿井下环境非结构化、局部可通行区域窄以及传统A^(*)算法规划路径存在搜索时间长、搜索节点多、路径冗余节点多、路径平滑度较差等问题,提出一种基于改进A^(*)算法的矿用巡检机器人路径规划算法。【方法】首先在传统A^(*... 【目的】针对煤矿井下环境非结构化、局部可通行区域窄以及传统A^(*)算法规划路径存在搜索时间长、搜索节点多、路径冗余节点多、路径平滑度较差等问题,提出一种基于改进A^(*)算法的矿用巡检机器人路径规划算法。【方法】首先在传统A^(*)算法的启发函数中引入预估消耗的指数函数和障碍物覆盖率之和,以提高搜索效率,缩短搜索时间;其次改进传统8邻域搜索为9邻域搜索,从而避免无用搜索,减少搜索节点数量;然后通过Floyd算法剔除路径中的冗余节点;最后采用改进3阶贝塞尔曲线完成路径平滑任务。【结果】结果表明:相较于传统A^(*)算法,在特定的20×20、30×30和40×40栅格地图下,改进A^(*)算法使得搜索时间分别缩短44.1%、63.8%和84.8%,搜索节点分别减少31.6%、47.9%和71%;路径平滑算法能够减少路径节点,改善路径平滑度,更适用于矿用巡检机器人的路径规划。 展开更多
关键词 矿用巡检机器人 路径规划 改进A^(*)算法 FLOYD算法 贝塞尔曲线
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基于障碍密度优先策略改进A^(*)算法的AGV路径规划
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作者 陈一馨 段宇轩 +2 位作者 刘豪 谭世界 郑天乐 《郑州大学学报(工学版)》 北大核心 2025年第2期26-34,共9页
针对传统A^(*)算法在障碍物较多的实际场景下进行AGV路径规划时,存在路径拐点多、路径冗余节点过多以及易陷入局部最优解等问题,提出一种改进A^(*)算法,采用栅格法进行环境建模。首先,在启发函数中引入障碍物密度函数K(n)改进代价函数,... 针对传统A^(*)算法在障碍物较多的实际场景下进行AGV路径规划时,存在路径拐点多、路径冗余节点过多以及易陷入局部最优解等问题,提出一种改进A^(*)算法,采用栅格法进行环境建模。首先,在启发函数中引入障碍物密度函数K(n)改进代价函数,用于更准确地估计当前节点到目标节点的实际代价;其次,采用动态邻域搜索策略提高算法的搜索效率和运行效率;最后,通过冗余节点处理策略减少路径拐点和删除冗余节点,得到只包含起点、转折点以及终点的路径。采用不同尺寸和复杂度的栅格环境地图进行仿真实验,结果表明:所提改进A^(*)算法与传统A^(*)算法以及其他改进的A^(*)算法相比,路径长度分别缩短了4.71%和2.07%,路径拐点数量分别减少了45.45%和20.54%,路径存在节点分别减少了82.24%和62.45%。 展开更多
关键词 路径规划 栅格地图 改进A^(*)算法 启发函数 动态邻域搜索 冗余节点优化
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基于改进A^(*)算法的机器人不平坦地形全局路径规划 被引量:3
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作者 郭聚刚 于军琪 +3 位作者 冯春勇 王凯 陈易圣 董振平 《计算机工程与应用》 北大核心 2025年第5期309-322,共14页
针对机器人在非结构化和不平整地形的路径规划问题,提出了一种基于改进A^(*)算法的全局路径规划方法。改进A^(*)算法引入双向搜索策略以提高算法计算速度。通过路径节点过滤克服了双向搜索策略带来的问题并减少了关键节点的数量,增加坡... 针对机器人在非结构化和不平整地形的路径规划问题,提出了一种基于改进A^(*)算法的全局路径规划方法。改进A^(*)算法引入双向搜索策略以提高算法计算速度。通过路径节点过滤克服了双向搜索策略带来的问题并减少了关键节点的数量,增加坡度约束降低了机器人的爬坡角度和侧倾角度,提高了规划路径的安全性,通过Bézier曲线拟合路径使其变得光滑,更有利于机器人的运动控制。在不同地形和障碍密度的高程图上进行实验,验证了改进的有效性。实验结果表明,与传统A^(*)算法相比,改进A^(*)算法在路径长度增加14.6%至37.84%的情况下,计算时间减少了71.05%至82.90%,关键节点数量减少了51.94%至70.53%,并且爬坡角度和侧倾角度显著减少,路径更加平滑。因此,该方法在提高效率的同时能够在非结构化和不平坦的地形下生成安全可靠的路径。 展开更多
关键词 路径规划 不平坦地形 改进A^(*)算法 移动机器人
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随机地图下改进A^(*)路径规划算法研究 被引量:2
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作者 林硕 金恒江 +1 位作者 韩忠华 赵剑明 《制造技术与机床》 北大核心 2025年第2期43-47,共5页
为解决传统算法在规划AGV(automated guided vehicles)路径时存在的节点多、路径不平滑和拓展范围广等问题,提出了一种改进A*算法。首先,采用栅格法建立环境信息;其次,通过加权后的障碍物比例对启发函数进行改进,同时增加防碰撞函数以... 为解决传统算法在规划AGV(automated guided vehicles)路径时存在的节点多、路径不平滑和拓展范围广等问题,提出了一种改进A*算法。首先,采用栅格法建立环境信息;其次,通过加权后的障碍物比例对启发函数进行改进,同时增加防碰撞函数以降低碰撞概率;最后,对所提出的改进算法进行拐角优化,减少AGV实际作业时的转弯次数。实验数据表明,简单环境下改进A^(*)算法的遍历节点数较两种传统算法分别缩短了85.3%、55.9%;复杂环境下改进A*算法的遍历节点数较两种传统算法缩短94.5%、70.3%。同时拐点数量减少、路径更加平滑、路径规划时间也大幅缩短,提高了运行效率并有效降低碰撞概率。 展开更多
关键词 路径规划 改进A^(*)算法 环境建模 拐角优化 防碰撞
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Global optimal path planning for mobile robot based onimproved Dijkstra algorithm and ant system algorithm 被引量:21
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作者 谭冠政 贺欢 Aaron Sloman 《Journal of Central South University of Technology》 EI 2006年第1期80-86,共7页
A novel method of global optimal path planning for mobile robot was proposed based on the improved Dijkstra algorithm and ant system algorithm. This method includes three steps: the first step is adopting the MAKLINK ... A novel method of global optimal path planning for mobile robot was proposed based on the improved Dijkstra algorithm and ant system algorithm. This method includes three steps: the first step is adopting the MAKLINK graph theory to establish the free space model of the mobile robot, the second step is adopting the improved Dijkstra algorithm to find out a sub-optimal collision-free path, and the third step is using the ant system algorithm to adjust and optimize the location of the sub-optimal path so as to generate the global optimal path for the mobile robot. The computer simulation experiment was carried out and the results show that this method is correct and effective. The comparison of the results confirms that the proposed method is better than the hybrid genetic algorithm in the global optimal path planning. 展开更多
关键词 mobile robot global optimal path planning improved Dijkstra algorithm ant system algorithm MAKLINK graph free MAKLINK line
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Improved algorithms to plan missions for agile earth observation satellites 被引量:3
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作者 Huicheng Hao Wei Jiang Yijun Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期811-821,共11页
This study concentrates of the new generation of the agile (AEOS). AEOS is a key study object on management problems earth observation satellite in many countries because of its many advantages over non-agile satell... This study concentrates of the new generation of the agile (AEOS). AEOS is a key study object on management problems earth observation satellite in many countries because of its many advantages over non-agile satellites. Hence, the mission planning and scheduling of AEOS is a popular research problem. This research investigates AEOS characteristics and establishes a mission planning model based on the working principle and constraints of AEOS as per analysis. To solve the scheduling issue of AEOS, several improved algorithms are developed. Simulation results suggest that these algorithms are effective. 展开更多
关键词 mission planning immune clone algorithm hybrid genetic algorithm (EA) improved ant colony algorithm general particle swarm optimization (PSO) agile earth observation satellite (AEOS).
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Improved algorithm of atmospheric refraction error in Longley-Rice channel model 被引量:2
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作者 Wang Zuliang Zheng Mao +1 位作者 Wang Juan Zheng Linhua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期683-687,共5页
Longley-Rice channel model modifies the atmospheric refraction by the equivalent earth radius method, which is simple calculation but is not accurate. As it only uses the horizontal difference, but does not make use o... Longley-Rice channel model modifies the atmospheric refraction by the equivalent earth radius method, which is simple calculation but is not accurate. As it only uses the horizontal difference, but does not make use of the vertical section information, it does not agree with the actual propagation path. The atmospheric refraction error correction method of the Longley-Rice channel model has been improved. The improved method makes use of the vertical section information sufficiently and maps the distance between the receiver and transmitter to the radio wave propagation distance, It can exactly reflect the infection of propagation distance for the radio wave propagation loss. It is predicted to be more close to the experimental results by simulation in comparison with the measured data. The effectiveness of improved methods is proved by simulation. 展开更多
关键词 radio wave propagation atmospheric refraction error correction algorithm improvement Longley- Rice model.
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Improved genetic algorithm freely searching for dangerous slip surface of slope 被引量:4
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作者 万文 曹平 +1 位作者 冯涛 袁海平 《Journal of Central South University of Technology》 EI 2005年第6期749-752,共4页
Based on the slice method of the non-circular slip surface for the calculation of integral stability of slope, an improved genetic algorithm was proposed, which can freely search for the most dangerous slip surface of... Based on the slice method of the non-circular slip surface for the calculation of integral stability of slope, an improved genetic algorithm was proposed, which can freely search for the most dangerous slip surface of slope and the corresponding minimum safety factor without supposing the geometric shape of the most dangerous slip surface. This improved genetic algorithm can simulate the genetic evolution process of organisms and avoid the local minimum value compared with the classical methods. The results of engineering cases show that it is a global optimal algorithm and has many advantages, such as higher efficiency and shorter time than the simple genetic algorithm. 展开更多
关键词 slice method dangerous non-circular slip surface minimum safety factor improved genetic algorithm
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Forecasting of wind velocity:An improved SVM algorithm combined with simulated annealing 被引量:2
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作者 刘金朋 牛东晓 +1 位作者 张宏运 王官庆 《Journal of Central South University》 SCIE EI CAS 2013年第2期451-456,共6页
Accurate forecasting of wind velocity can improve the economic dispatch and safe operation of the power system. Support vector machine (SVM) has been proved to be an efficient approach for forecasting. According to th... Accurate forecasting of wind velocity can improve the economic dispatch and safe operation of the power system. Support vector machine (SVM) has been proved to be an efficient approach for forecasting. According to the analysis with support vector machine method, the drawback of determining the parameters only by experts' experience should be improved. After a detailed description of the methodology of SVM and simulated annealing, an improved algorithm was proposed for the automatic optimization of parameters using SVM method. An example has proved that the proposed method can efficiently select the parameters of the SVM method. And by optimizing the parameters, the forecasting accuracy of the max wind velocity increases by 34.45%, which indicates that the new SASVM model improves the forecasting accuracy. 展开更多
关键词 wind velocity forecasting improved algorithm simulated annealing support vector machine
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An improved self-adaptive membrane computing optimization algorithm and its applications in residue hydrogenating model parameter estimation 被引量:1
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作者 芦会彬 薄翠梅 杨世品 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3909-3915,共7页
In order to solve the non-linear and high-dimensional optimization problems more effectively, an improved self-adaptive membrane computing(ISMC) optimization algorithm was proposed. The proposed ISMC algorithm applied... In order to solve the non-linear and high-dimensional optimization problems more effectively, an improved self-adaptive membrane computing(ISMC) optimization algorithm was proposed. The proposed ISMC algorithm applied improved self-adaptive crossover and mutation formulae that can provide appropriate crossover operator and mutation operator based on different functions of the objects and the number of iterations. The performance of ISMC was tested by the benchmark functions. The simulation results for residue hydrogenating kinetics model parameter estimation show that the proposed method is superior to the traditional intelligent algorithms in terms of convergence accuracy and stability in solving the complex parameter optimization problems. 展开更多
关键词 optimization algorithm membrane computing benchmark function improved self-adaptive operator
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基于Theta^(*)算法和启发路径的无人艇全局路径规划
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作者 杜家辉 李恒宇 +2 位作者 瞿栋 鲍凌志 钟雨轩 《中国测试》 北大核心 2025年第5期101-109,共9页
在无人艇全局路径规划中,许多算法仅考虑效率而忽略航行安全性。为满足安全性需求,该文提出一种由启发路径构建风险评估函数,并引导最终规划路径向启发路径靠拢的方法。首先,依据启发路径的周围环境构建风险评估函数;其次,对Theta^(*)... 在无人艇全局路径规划中,许多算法仅考虑效率而忽略航行安全性。为满足安全性需求,该文提出一种由启发路径构建风险评估函数,并引导最终规划路径向启发路径靠拢的方法。首先,依据启发路径的周围环境构建风险评估函数;其次,对Theta^(*)算法进行改良,将路径代价作为父节点选取的指标之一;最后,提出一种非均匀代价的计算方式,并与改良Theta^(*)算法相结合,进而得到一条能够避开危险区域,兼具效率与安全性的全局路径。此外,通过一系列实验表明,该文方法成功绕开危险区域,并可根据具体任务需求调整危险系数大小,以较少的路径长度增加换取路径安全性的大幅提升,在实际环境中能够有效规划一条满足任务需求的全局路径。 展开更多
关键词 无人艇 路径规划 启发路径 改良Theta^(*)算法
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Study of Direction Probability and Algorithm of Improved Marriage in Honey Bees Optimization for Weapon Network System 被引量:2
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作者 杨晨光 涂序彦 陈杰 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第2期152-157,共6页
To solve the weapon network system optimization problem against small raid objects with low attitude,the concept of direction probability and a new evaluation index system are proposed.By calculating the whole damagin... To solve the weapon network system optimization problem against small raid objects with low attitude,the concept of direction probability and a new evaluation index system are proposed.By calculating the whole damaging probability that changes with the defending angle,the efficiency of the whole weapon network system can be subtly described.With such method,we can avoid the inconformity of the description obtained from the traditional index systems.Three new indexes are also proposed,i.e.join index,overlap index and cover index,which help manage the relationship among several sub-weapon-networks.By normalizing the computation results with the Sigmoid function,the matching problem between the optimization algorithm and indexes is well settled.Also,the algorithm of improved marriage in honey bees optimization that proposed in our previous work is applied to optimize the embattlement problem.Simulation is carried out to show the efficiency of the proposed indexes and the optimization algorithm. 展开更多
关键词 网络系统 优化问题 破坏概率 算法改进 核武器 蜜蜂 婚姻 SIGMOID函数
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Improved hyper-spherical search algorithm for voltage total harmonic distortion minimization in 27-level inverter
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作者 A A KHODADOOST ARANI H KARAMI +1 位作者 B VAHIDI G B GHAREHPETIAN 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第10期2822-2832,共11页
Multi-level inverters(MLIs)have become popular in different applications such as industrial power control systems and distributed generations.There are different forms of MLIs.The cascaded MLIs(CMLIs)have some special... Multi-level inverters(MLIs)have become popular in different applications such as industrial power control systems and distributed generations.There are different forms of MLIs.The cascaded MLIs(CMLIs)have some special advantages among them such as more different output voltage levels using the same number of components and higher power quality.In this paper,a 27-level inverter switching algorithm considering total harmonic distortion(THD)minimization is investigated.Switching angles of the inverter switches are achieved by minimizing a THD-based objective function.In order to minimize the THD-based objective function,the hyper-spherical search(HSS)algorithm,as a novel optimization algorithm,is improved and the results of improved HSS(IHSS)are compared with HSS algorithm and other five evolutionary algorithms to show the advantages of IHSS algorithm. 展开更多
关键词 27-level inverter cascade multi-level inverter improved hyper-spherical search(IHSS)algorithm total harmonic distortion(THD)minimization
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基于双向搜索改进A^(*)算法的无人艇全局路径规划
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作者 梅梦磊 陈顺洪 +1 位作者 菅永坤 白立 《舰船科学技术》 北大核心 2025年第5期97-102,共6页
为解决传统A^(*)算法搜索效率低、路径拐点多、贴近障碍物等问题,结合无人艇特性,提出一种改进A^(*)算法。首先,引入人工势场法对评价函数进行改进,考虑障碍物斥力场的影响,提高路径安全性;其次,通过改进节点遍历方式和双向搜索机制减... 为解决传统A^(*)算法搜索效率低、路径拐点多、贴近障碍物等问题,结合无人艇特性,提出一种改进A^(*)算法。首先,引入人工势场法对评价函数进行改进,考虑障碍物斥力场的影响,提高路径安全性;其次,通过改进节点遍历方式和双向搜索机制减少搜索节点,提高路径规划速度;最后,对生成路径进行二次优化,删除冗余节点,提升路径平滑性。仿真结果表明,开阔水域场景下改进A^(*)算法在安全性、路径长度、路径平滑性、规划速度方面均有较大提升;岛礁区场景下改进A^(*)算法虽然在路径长度上有所牺牲,但安全性、路径平滑性、规划速度方面具有明显优势。研究成果可为无人艇全局路径规划问题研究提供一定的参考。 展开更多
关键词 路径规划 改进A^(*)算法 斥力场 双向搜索
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融合改进双向A^(∗)与动态窗口法的仓储移动机器人路径规划
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作者 刘震 张洪 《现代制造工程》 北大核心 2025年第5期99-105,134,共8页
针对传统A^(∗)算法在复杂环境下搜索效果差、路径曲折、拐角与障碍物距离过近且避障能力差等问题,提出了一种融合改进双向A^(∗)与动态窗口法(Dynamic Window Approach,DWA)的机器人路径规划算法。首先,引入双向搜索机制与自适应启发函数... 针对传统A^(∗)算法在复杂环境下搜索效果差、路径曲折、拐角与障碍物距离过近且避障能力差等问题,提出了一种融合改进双向A^(∗)与动态窗口法(Dynamic Window Approach,DWA)的机器人路径规划算法。首先,引入双向搜索机制与自适应启发函数,以提高算法的搜索速度;其次,应用线段相交法结合安全距离判定剔除冗余点,以确保路径更加安全、平缓;然后,在DWA中加入方位角与目标点距离判定,以增强算法的避障能力;最后,在优化后的全局路径上分段使用DWA进行实时避障。仿真结果显示,融合算法能在复杂场景下生成安全边界内的平滑路径,有效躲避障碍物,快速到达目标点。 展开更多
关键词 路径规划 改进A^(∗)算法 动态窗口法 实时避障
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基于Improved-HMM的进程行为异常检测 被引量:2
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作者 党小超 马峻 郝占军 《计算机工程与设计》 CSCD 北大核心 2011年第4期1264-1267,共4页
针对传统隐马尔可夫模型(HMM)状态转移概率仅与前一状态有关的不足,提出了一种改进的隐马尔可夫模型(Im-proved-HMM),该模型考虑到状态转移概率与前两时刻状态相关,旨在提高异常检测准确率。用基于Improved-HMM的Baum-Welch(BW)算法对... 针对传统隐马尔可夫模型(HMM)状态转移概率仅与前一状态有关的不足,提出了一种改进的隐马尔可夫模型(Im-proved-HMM),该模型考虑到状态转移概率与前两时刻状态相关,旨在提高异常检测准确率。用基于Improved-HMM的Baum-Welch(BW)算法对正常进程行为进行建模,并采用滑动窗口的方法,检测进程行为是否处于异常状态。实验结果表明,该模型的检测准确率高于传统的HMM模型,能及时、准确检测到进程行为的异常。 展开更多
关键词 改进的隐马尔可夫模型 异常检测 系统调用序列 鲍姆-韦尔奇算法 滑动窗口
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基于改进A^(*)算法+LM-BZS算法的农业机器人路径规划 被引量:7
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作者 张万枝 赵威 +3 位作者 李玉华 赵乐俊 侯加林 朱倩 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期81-92,共12页
针对目前农业机器人在全局路径规划过程中存在规划效率低、规划路径折线段多、折线角度大、作业不稳定等问题,以果园履带机器人为运动学模型,提出一种基于改进A^(*)算法+低阶多段贝塞尔曲线拼接(Low-order multi-segment Bezier curve s... 针对目前农业机器人在全局路径规划过程中存在规划效率低、规划路径折线段多、折线角度大、作业不稳定等问题,以果园履带机器人为运动学模型,提出一种基于改进A^(*)算法+低阶多段贝塞尔曲线拼接(Low-order multi-segment Bezier curve splicing,LM-BZS)算法的路径规划方法。首先,根据先验地图获取果园环境信息,将果树和障碍物视作不可通行区域,并结合机器人本体尺寸,对不可通行区域进行膨胀拟合处理;然后,利用改进A^(*)算法搜索路径,对初步生成路径进行树行节点调整;最后,采用LM-BZS算法对调整后的路径点进行优化处理,生成符合果园履带机器人作业要求的行驶路径。仿真试验结果表明,相较于传统A^(*)算法,本文所提出的改进算法在无障碍和有障碍环境中,路径规划时间分别减少76.75%、86.40%,节点评估数量分别减少36.68%、39.37%;经LM-BZS算法优化所得路径在无障碍环境中,相较于传统A^(*)算法和高阶贝塞尔算法,平均曲率分别降低45.81%、18.94%;在有障碍环境中平均曲率分别降低56.98%、27.81%。场地试验结果表明,果园履带机器人在对本文算法生成路径进行跟踪行驶时,在无障碍和有障碍环境中,最大横向误差分别为0.428、0.491 m,平均横向误差分别为0.232、0.276 m,平均航向偏差分别为11.06°、13.76°,符合果园履带机器人自主行驶条件。 展开更多
关键词 农业机器人 改进A^(*)算法 路径规划 LM-BZS算法
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