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Adaptive dwell scheduling based on Q-learning for multifunctional radar system
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作者 HENG Siyu CHENG Ting +2 位作者 HE Zishu WANG Yuanqing LIU Luqing 《Journal of Systems Engineering and Electronics》 2025年第4期985-993,共9页
The dwell scheduling problem for a multifunctional radar system is led to the formation of corresponding optimiza-tion problem.In order to solve the resulting optimization prob-lem,the dwell scheduling process in a sc... The dwell scheduling problem for a multifunctional radar system is led to the formation of corresponding optimiza-tion problem.In order to solve the resulting optimization prob-lem,the dwell scheduling process in a scheduling interval(SI)is formulated as a Markov decision process(MDP),where the state,action,and reward are specified for this dwell scheduling problem.Specially,the action is defined as scheduling the task on the left side,right side or in the middle of the radar idle time-line,which reduces the action space effectively and accelerates the convergence of the training.Through the above process,a model-free reinforcement learning framework is established.Then,an adaptive dwell scheduling method based on Q-learn-ing is proposed,where the converged Q value table after train-ing is utilized to instruct the scheduling process.Simulation results demonstrate that compared with existing dwell schedul-ing algorithms,the proposed one can achieve better scheduling performance considering the urgency criterion,the importance criterion and the desired execution time criterion comprehen-sively.The average running time shows the proposed algorithm has real-time performance. 展开更多
关键词 multifunctional radar dwell scheduling reinforce-ment learning q-learning.
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Traffic Control Based on Integrated Kalman Filtering and Adaptive Quantized Q-Learning Framework for Internet of Vehicles
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作者 Othman S.Al-Heety Zahriladha Zakaria +4 位作者 Ahmed Abu-Khadrah Mahamod Ismail Sarmad Nozad Mahmood Mohammed Mudhafar Shakir Hussein Alsariera 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2103-2127,共25页
Intelligent traffic control requires accurate estimation of the road states and incorporation of adaptive or dynamically adjusted intelligent algorithms for making the decision.In this article,these issues are handled... Intelligent traffic control requires accurate estimation of the road states and incorporation of adaptive or dynamically adjusted intelligent algorithms for making the decision.In this article,these issues are handled by proposing a novel framework for traffic control using vehicular communications and Internet of Things data.The framework integrates Kalman filtering and Q-learning.Unlike smoothing Kalman filtering,our data fusion Kalman filter incorporates a process-aware model which makes it superior in terms of the prediction error.Unlike traditional Q-learning,our Q-learning algorithm enables adaptive state quantization by changing the threshold of separating low traffic from high traffic on the road according to the maximum number of vehicles in the junction roads.For evaluation,the model has been simulated on a single intersection consisting of four roads:east,west,north,and south.A comparison of the developed adaptive quantized Q-learning(AQQL)framework with state-of-the-art and greedy approaches shows the superiority of AQQL with an improvement percentage in terms of the released number of vehicles of AQQL is 5%over the greedy approach and 340%over the state-of-the-art approach.Hence,AQQL provides an effective traffic control that can be applied in today’s intelligent traffic system. 展开更多
关键词 q-learning intelligent transportation system(ITS) traffic control vehicular communication kalman filtering smart city Internet of Things
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玻尔兹曼优化Q-learning的高速铁路越区切换控制算法 被引量:3
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作者 陈永 康婕 《控制理论与应用》 北大核心 2025年第4期688-694,共7页
针对5G-R高速铁路越区切换使用固定切换阈值,且忽略了同频干扰、乒乓切换等的影响,导致越区切换成功率低的问题,提出了一种玻尔兹曼优化Q-learning的越区切换控制算法.首先,设计了以列车位置–动作为索引的Q表,并综合考虑乒乓切换、误... 针对5G-R高速铁路越区切换使用固定切换阈值,且忽略了同频干扰、乒乓切换等的影响,导致越区切换成功率低的问题,提出了一种玻尔兹曼优化Q-learning的越区切换控制算法.首先,设计了以列车位置–动作为索引的Q表,并综合考虑乒乓切换、误码率等构建Q-learning算法回报函数;然后,提出玻尔兹曼搜索策略优化动作选择,以提高切换算法收敛性能;最后,综合考虑基站同频干扰的影响进行Q表更新,得到切换判决参数,从而控制切换执行.仿真结果表明:改进算法在不同运行速度和不同运行场景下,较传统算法能有效提高切换成功率,且满足无线通信服务质量QoS的要求. 展开更多
关键词 越区切换 5G-R q-learning算法 玻尔兹曼优化策略
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基于Adaptive LASSO模型辅助校准的非概率样本与概率样本融合研究
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作者 王小宁 孙敏 邹梦文 《调研世界》 2025年第9期84-96,共13页
在过往的调查研究中,大部分统计研究者所使用的都是概率样本进行估计,但随着数据技术的发展与概率抽样成本的增加,非概率抽样的时效性与便捷性使其使用率日益上升。基于这一研究背景,考虑辅助变量高维的情况下,将Adaptive LASSO引入模... 在过往的调查研究中,大部分统计研究者所使用的都是概率样本进行估计,但随着数据技术的发展与概率抽样成本的增加,非概率抽样的时效性与便捷性使其使用率日益上升。基于这一研究背景,考虑辅助变量高维的情况下,将Adaptive LASSO引入模型辅助校准估计法,筛选出相关性强的辅助变量对非概率样本的权数进行校准,解决由于非概率样本入样概率未知而导致难以进行统计推断的问题,实现非概率样本与概率样本融合来估计总体。通过模拟分析以及利用网民社会意识调查和中国社会状况综合调查两个数据集进行的实证分析,验证了本文提出的基于Adaptive LASSO进行模型辅助校准的数据融合方法可有效提高估计的精度。 展开更多
关键词 数据融合 模型辅助校准 adaptive LASSO
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无监督环境下改进Q-learning算法在网络异常诊断中的应用
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作者 梁西陈 《六盘水师范学院学报》 2025年第3期89-97,共9页
针对无监督环境下传统网络异常诊断算法存在异常点定位和异常数据分类准确率低等不足,通过设计一种基于改进Q-learning算法的无线网络异常诊断方法:首先基于ADU(Asynchronous Data Unit异步数据单元)单元采集无线网络的数据流,并提取数... 针对无监督环境下传统网络异常诊断算法存在异常点定位和异常数据分类准确率低等不足,通过设计一种基于改进Q-learning算法的无线网络异常诊断方法:首先基于ADU(Asynchronous Data Unit异步数据单元)单元采集无线网络的数据流,并提取数据包特征;然后构建Q-learning算法模型探索状态值和奖励值的平衡点,利用SA(Simulated Annealing模拟退火)算法从全局视角对下一时刻状态进行精确识别;最后确定训练样本的联合分布概率,提升输出值的逼近性能以达到平衡探索与代价之间的均衡。测试结果显示:改进Q-learning算法的网络异常定位准确率均值达99.4%,在不同类型网络异常的分类精度和分类效率等方面,也优于三种传统网络异常诊断方法。 展开更多
关键词 无监督 改进q-learning ADU单元 状态值 联合分布概率
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基于Q-learning算法的机场航班延误预测 被引量:1
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作者 刘琪 乐美龙 《航空计算技术》 2025年第1期28-32,共5页
将改进的深度信念网络(DBN)和Q-learning算法结合建立组合预测模型。首先将延误预测问题建模为一个标准的马尔可夫决策过程,使用改进的深度信念网络来选择关键特征。经深度信念网络分析,从46个特征变量中选择出27个关键特征类别作为延... 将改进的深度信念网络(DBN)和Q-learning算法结合建立组合预测模型。首先将延误预测问题建模为一个标准的马尔可夫决策过程,使用改进的深度信念网络来选择关键特征。经深度信念网络分析,从46个特征变量中选择出27个关键特征类别作为延误时间的最终解释变量输入Q-learning算法中,从而实现对航班延误的实时预测。使用北京首都国际机场航班数据进行测试实验,实验结果表明,所提出的模型可以有效预测航班延误,平均误差为4.05 min。将提出的组合算法性能与4种基准方法进行比较,基于DBN的Q-learning算法的延误预测准确性高于另外四种算法,具有较高的预测精度。 展开更多
关键词 航空运输 航班延误预测 深度信念网络 q-learning 航班延误
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基于天球网格的大规模LEO星座Q-Learning QoS路由算法
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作者 马伟 肖嵩 +1 位作者 周诠 蔡宇茜 《空间电子技术》 2025年第S1期132-139,共8页
智能化QoS路由是大规模LEO星座的研究热点和难点。文章聚焦LEO星座虚实拓扑漂移、多业务QoS冲突、动态负载失衡等问题,提出了一种基于天球网格的Q-Learning QoS路由算法。通过将非均匀离散化天球与北斗网格编码融合,解决链路频繁切换及... 智能化QoS路由是大规模LEO星座的研究热点和难点。文章聚焦LEO星座虚实拓扑漂移、多业务QoS冲突、动态负载失衡等问题,提出了一种基于天球网格的Q-Learning QoS路由算法。通过将非均匀离散化天球与北斗网格编码融合,解决链路频繁切换及虚实拓扑同步问题。在此基础上结合业务热力图设计了Q-Learning路由算法,以带宽、负载、热力等级、跳数为联合优化目标,构建差异化QoS奖励机制,通过实时学习动态规避拥塞链路。仿真结果表明,本文算法相较HLLMR和Dijkstra算法,丢包率分别降低4%和11%,吞吐量提升7%和15%,时延与HLLMR相当,实现了大规模LEO星座QoS保障与负载均衡的协同优化。 展开更多
关键词 天球网格 热力图 q-learning QOS路由
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融合Q-learning的A^(*)预引导蚁群路径规划算法
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作者 殷笑天 杨丽英 +1 位作者 刘干 何玉庆 《传感器与微系统》 北大核心 2025年第8期143-147,153,共6页
针对传统蚁群优化(ACO)算法在复杂环境路径规划中存在易陷入局部最优、收敛速度慢及避障能力不足的问题,提出了一种融合Q-learning基于分层信息素机制的A^(*)算法预引导蚁群路径规划算法-QHACO算法。首先,通过A^(*)算法预分配全局信息素... 针对传统蚁群优化(ACO)算法在复杂环境路径规划中存在易陷入局部最优、收敛速度慢及避障能力不足的问题,提出了一种融合Q-learning基于分层信息素机制的A^(*)算法预引导蚁群路径规划算法-QHACO算法。首先,通过A^(*)算法预分配全局信息素,引导初始路径快速逼近最优解;其次,构建全局-局部双层信息素协同模型,利用全局层保留历史精英路径经验、局部层实时响应环境变化;最后,引入Q-learning方向性奖励函数优化决策过程,在路径拐点与障碍边缘施加强化引导信号。实验表明:在25×24中等复杂度地图中,QHACO算法较传统ACO算法最优路径缩短22.7%,收敛速度提升98.7%;在50×50高密度障碍环境中,最优路径长度优化16.9%,迭代次数减少95.1%。相比传统ACO算法,QHACO算法在最优性、收敛速度与避障能力上均有显著提升,展现出较强环境适应性。 展开更多
关键词 蚁群优化算法 路径规划 局部最优 收敛速度 q-learning 分层信息素 A^(*)算法
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改进的自校正Q-learning应用于智能机器人路径规划 被引量:1
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作者 任伟 朱建鸿 《机械科学与技术》 北大核心 2025年第1期126-132,共7页
为了解决智能机器人路径规划中存在的一些问题,提出了一种改进的自校正Q-learning算法。首先,对其贪婪搜索因子进行了改进,采用动态的搜索因子,对探索和利用之间的关系进行了更好地平衡;其次,在Q值初始化阶段,利用当前位置和目标位置距... 为了解决智能机器人路径规划中存在的一些问题,提出了一种改进的自校正Q-learning算法。首先,对其贪婪搜索因子进行了改进,采用动态的搜索因子,对探索和利用之间的关系进行了更好地平衡;其次,在Q值初始化阶段,利用当前位置和目标位置距离的倒数代替传统的Q-learning算法中的全零或随机初始化,大大加快了收敛速度;最后,针对传统的Q-learning算法中Q函数的最大化偏差,引入自校正估计器来修正最大化偏差。通过仿真实验对提出的改进思路进行了验证,结果表明:改进的算法能够很大程度的提高算法的学习效率,在各个方面相比传统算法都有了较大的提升。 展开更多
关键词 路径规划 q-learning 贪婪搜索 初始化 自校正
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基于非策略Q-learning的欺骗攻击下未知线性离散系统最优跟踪控制
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作者 宋星星 储昭碧 《控制与决策》 北大核心 2025年第5期1641-1650,共10页
针对多重欺骗攻击下动力学信息未知的线性离散系统,提出一种非策略Q-learning算法解决系统的最优跟踪控制问题.首先,考虑加入一个权重矩阵建立控制器通信信道遭受多重欺骗攻击的输入模型,并结合参考命令生成器构建增广跟踪系统.在线性... 针对多重欺骗攻击下动力学信息未知的线性离散系统,提出一种非策略Q-learning算法解决系统的最优跟踪控制问题.首先,考虑加入一个权重矩阵建立控制器通信信道遭受多重欺骗攻击的输入模型,并结合参考命令生成器构建增广跟踪系统.在线性二次跟踪框架内将系统的最优跟踪控制表达为欺骗攻击与控制输入同时参与的零和博弈问题.其次,设计一种基于状态数据的非策略Q-learning算法学习系统最优跟踪控制增益,解决应用中控制增益不能按照给定要求更新的问题,并证明在满足持续激励条件的探测噪声下该算法的求解不存在偏差.同时考虑系统状态不可测的情况,设计基于输出数据的非策略Q-learning算法.最后,通过对F-16飞机自动驾驶仪的跟踪控制仿真,验证所设计非策略Q-learning算法的有效性以及对探测噪声影响的无偏性. 展开更多
关键词 欺骗攻击 最优跟踪 非策略q-learning 零和博弈
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基于Q-learning的改进NSGA-Ⅲ求解高维多目标柔性作业车间调度问题
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作者 张小培 陈勇 +1 位作者 王宸 袁春辉 《湖北汽车工业学院学报》 2025年第3期56-63,共8页
针对机械加工车间多品种、小批量的生产模式,以最小化总能耗、最大完工时间、机器负载和总拖期为优化目标建立高维多目标柔性作业车间调度模型,并利用改进NSGA-Ⅲ进行求解。采用机器、工序和批量的三重编码方式进行编码,通过Logistic映... 针对机械加工车间多品种、小批量的生产模式,以最小化总能耗、最大完工时间、机器负载和总拖期为优化目标建立高维多目标柔性作业车间调度模型,并利用改进NSGA-Ⅲ进行求解。采用机器、工序和批量的三重编码方式进行编码,通过Logistic映射生成初始混沌序列初始化种群,根据目标解的质量指标构建强化学习状态空间,通过Q-learning训练调整邻域搜索策略。最后通过对比基准算例及实例验证了模型的有效性和优越性。 展开更多
关键词 柔性作业 目标优化 批量调度 q-learning 邻域搜索
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基于Double Q-Learning的改进蝗虫算法求解分布式柔性作业车间逆调度问题
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作者 胡旭伦 唐红涛 《机床与液压》 北大核心 2025年第20期52-63,共12页
针对分布式柔性作业车间中存在的资源分配不均和调度稳定性不足问题,构建以最小化最大完工时间、机器总能耗和偏离度为目标的逆调度数学模型,提出一种基于Double Q-Learning的改进多目标蝗虫优化算法(DQIGOA)。针对该问题设计一种混合... 针对分布式柔性作业车间中存在的资源分配不均和调度稳定性不足问题,构建以最小化最大完工时间、机器总能耗和偏离度为目标的逆调度数学模型,提出一种基于Double Q-Learning的改进多目标蝗虫优化算法(DQIGOA)。针对该问题设计一种混合三层编码方式;提出一种基于逆调度特点的种群初始化方式以提高种群质量;引入权重平衡因子来提高非支配解存档中解集的多样性;将强化学习中的Double Q-Learning机制融入非支配解的选择过程,通过动态动作策略优化目标解的选取,提升调度方案的全局搜索能力与局部优化效率。最后构建26组算例,通过策略有效性分析证明了所提策略可显著提升DQIGOA算法的性能,并通过与NSGA-II、DE和SPEA-II算法进行对比证明DQIGOA算法的有效性。结果表明:相比NSGA-II、DE和SPEA-II算法,DQIGOA算法在HV、IGD、SP指标上均有优势,证明了DQIGOA能够有效提升解的收敛速度和多样性分布,在动态扰动条件下表现出更强的鲁棒性。 展开更多
关键词 分布式柔性作业车间 逆调度 蝗虫算法 Double q-learning机制
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基于Q-learning的广域物联网热点地区MAC层机制设计
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作者 雷迪 刘向 +4 位作者 孙文彬 杨欣 许茜 陈丽丽 易波 《移动通信》 2025年第8期90-95,共6页
在广域物联网应用中,热点地区由于终端密集接入、业务负载波动大,存在接入冲突频发、信道资源利用率低下等问题。作为共享无线信道管理重要一环,MAC层协议在提升系统吞吐量与接入效率方面发挥着核心作用。分析了热点地区MAC层协议所需特... 在广域物联网应用中,热点地区由于终端密集接入、业务负载波动大,存在接入冲突频发、信道资源利用率低下等问题。作为共享无线信道管理重要一环,MAC层协议在提升系统吞吐量与接入效率方面发挥着核心作用。分析了热点地区MAC层协议所需特征,提出基于Q-learning算法的优化方案,在节点侧引入强化学习模型以实现参数自适应调整。在传统CSMA/CA协议基础上,设计了结合动态RTS/CTS机制与动态退避窗口的接入机制。仿真结果表明,所提出的优化方案在系统吞吐量、平衡信道冲突率与利用率方面有一定提升。 展开更多
关键词 物联网 MAC层协议 CSMA/CA q-learning
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面向物流机器人的改进Q-Learning动态避障算法研究 被引量:1
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作者 王力 赵全海 黄石磊 《计算机测量与控制》 2025年第3期267-274,共8页
为提升物流机器人(AMR)在复杂环境中的自主导航与避障能力,改善传统Q-Learning算法在动态环境中的收敛速度慢、路径规划不够优化等问题;研究引入模糊退火算法对Q-Learning算法进行路径节点和搜索路径优化,删除多余节点和非必要转折;并... 为提升物流机器人(AMR)在复杂环境中的自主导航与避障能力,改善传统Q-Learning算法在动态环境中的收敛速度慢、路径规划不够优化等问题;研究引入模糊退火算法对Q-Learning算法进行路径节点和搜索路径优化,删除多余节点和非必要转折;并为平衡好Q-Learning算法的探索和利用问题,提出以贪婪法优化搜索策略,并借助改进动态窗口法对进行路径节点和平滑加速改进,实现局部路径规划,以提高改进Q-Learning算法在AMR动态避障中的搜索性能和效率;结果表明,改进Q-Learning算法能有效优化搜索路径,能较好避开动态障碍物和静态障碍物,与其他算法的距离差幅至少大于1 m;改进算法在局部路径中的避障轨迹更趋近于期望值,最大搜索时间不超过3 s,优于其他算法,且其在不同场景下的避障路径长度和运动时间减少幅度均超过10%,避障成功率超过90%;研究方法能满足智慧仓储、智能制造等工程领域对物流机器人高效、安全作业的需求。 展开更多
关键词 物流机器人 q-learning算法 DWA 多目标规划 障碍物 避障
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基于改进Q-Learning算法的机器人路径规划 被引量:1
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作者 潘琦涛 赵岳生 甘育国 《物联网技术》 2025年第3期82-86,共5页
移动机器人的路径规划问题受到了广大学者的关注。当机器人在未知环境中进行路径规划时,为了提高规划的效率,通常需要获取相关的先验知识。在强化学习路径规划中,先验知识可以通过多种方式融入到算法中,其中Q-Learning算法是一种常用的... 移动机器人的路径规划问题受到了广大学者的关注。当机器人在未知环境中进行路径规划时,为了提高规划的效率,通常需要获取相关的先验知识。在强化学习路径规划中,先验知识可以通过多种方式融入到算法中,其中Q-Learning算法是一种常用的方法。传统的Q-Learning算法路径规划存在拐点多、路径长、训练轮次多等问题。因此,提出一种改进算法,针对原Q-Learning算法在机器人路径规划中存在的学习速度慢、探索效率低、规划路径长等突出问题进行了优化。首先,基于栅格地图,在传统算法的基础上采用径向基函数(RBF)网络对Q-Learning算法的动作值函数进行逼近;其次,为了平衡探索与利用的比例,采用了动态调整贪婪因子的方法;最后,增加了机器人可选择的动作,扩充了动作集,改进为八方向探索。仿真结果表明,与Q-Learning算法相比,改进后的Q-Learning算法可将最优路径长度缩短23.33%,拐点个数减少63.16%,算法训练轮次减少31.22%。 展开更多
关键词 q-learning ROS机器人 强化学习 路径规划 径向基函数 探索策略
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Adaptive optoelectronic transistor for intelligent vision system 被引量:1
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作者 Yiru Wang Shanshuo Liu +5 位作者 Hongxin Zhang Yuchen Cao Zitong Mu Mingdong Yi Linghai Xie Haifeng Ling 《Journal of Semiconductors》 2025年第2期53-70,共18页
Recently,for developing neuromorphic visual systems,adaptive optoelectronic devices become one of the main research directions and attract extensive focus to achieve optoelectronic transistors with high performances a... Recently,for developing neuromorphic visual systems,adaptive optoelectronic devices become one of the main research directions and attract extensive focus to achieve optoelectronic transistors with high performances and flexible func-tionalities.In this review,based on a description of the biological adaptive functions that are favorable for dynamically perceiv-ing,filtering,and processing information in the varying environment,we summarize the representative strategies for achiev-ing these adaptabilities in optoelectronic transistors,including the adaptation for detecting information,adaptive synaptic weight change,and history-dependent plasticity.Moreover,the key points of the corresponding strategies are comprehen-sively discussed.And the applications of these adaptive optoelectronic transistors,including the adaptive color detection,sig-nal filtering,extending the response range of light intensity,and improve learning efficiency,are also illustrated separately.Lastly,the challenges faced in developing adaptive optoelectronic transistor for artificial vision system are discussed.The descrip-tion of biological adaptive functions and the corresponding inspired neuromorphic devices are expected to provide insights for the design and application of next-generation artificial visual systems. 展开更多
关键词 adaptive optoelectronic transistor neuromorphic computing artificial vision
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Improved Event-Triggered Adaptive Neural Network Control for Multi-agent Systems Under Denial-of-Service Attacks 被引量:1
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作者 Huiyan ZHANG Yu HUANG +1 位作者 Ning ZHAO Peng SHI 《Artificial Intelligence Science and Engineering》 2025年第2期122-133,共12页
This paper addresses the consensus problem of nonlinear multi-agent systems subject to external disturbances and uncertainties under denial-ofservice(DoS)attacks.Firstly,an observer-based state feedback control method... This paper addresses the consensus problem of nonlinear multi-agent systems subject to external disturbances and uncertainties under denial-ofservice(DoS)attacks.Firstly,an observer-based state feedback control method is employed to achieve secure control by estimating the system's state in real time.Secondly,by combining a memory-based adaptive eventtriggered mechanism with neural networks,the paper aims to approximate the nonlinear terms in the networked system and efficiently conserve system resources.Finally,based on a two-degree-of-freedom model of a vehicle affected by crosswinds,this paper constructs a multi-unmanned ground vehicle(Multi-UGV)system to validate the effectiveness of the proposed method.Simulation results show that the proposed control strategy can effectively handle external disturbances such as crosswinds in practical applications,ensuring the stability and reliable operation of the Multi-UGV system. 展开更多
关键词 multi-agent systems neural network DoS attacks memory-based adaptive event-triggered mechanism
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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity
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作者 Moawiah M.Naffaa 《Neural Regeneration Research》 SCIE CAS 2025年第6期1565-1581,共17页
Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inh... Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior. 展开更多
关键词 network adaptability NEUROGENESIS neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity
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DnCNN-RM:an adaptive SAR image denoising algorithm based on residual networks
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作者 OU Hai-ning LI Chang-di +3 位作者 ZENG Rui-bin WU Yan-feng LIU Jia-ning CHENG Peng 《中国光学(中英文)》 北大核心 2025年第5期1209-1218,共10页
In the field of image processing,the analysis of Synthetic Aperture Radar(SAR)images is crucial due to its broad range of applications.However,SAR images are often affected by coherent speckle noise,which significantl... In the field of image processing,the analysis of Synthetic Aperture Radar(SAR)images is crucial due to its broad range of applications.However,SAR images are often affected by coherent speckle noise,which significantly degrades image quality.Traditional denoising methods,typically based on filter techniques,often face challenges related to inefficiency and limited adaptability.To address these limitations,this study proposes a novel SAR image denoising algorithm based on an enhanced residual network architecture,with the objective of enhancing the utility of SAR imagery in complex electromagnetic environments.The proposed algorithm integrates residual network modules,which directly process the noisy input images to generate denoised outputs.This approach not only reduces computational complexity but also mitigates the difficulties associated with model training.By combining the Transformer module with the residual block,the algorithm enhances the network's ability to extract global features,offering superior feature extraction capabilities compared to CNN-based residual modules.Additionally,the algorithm employs the adaptive activation function Meta-ACON,which dynamically adjusts the activation patterns of neurons,thereby improving the network's feature extraction efficiency.The effectiveness of the proposed denoising method is empirically validated using real SAR images from the RSOD dataset.The proposed algorithm exhibits remarkable performance in terms of EPI,SSIM,and ENL,while achieving a substantial enhancement in PSNR when compared to traditional and deep learning-based algorithms.The PSNR performance is enhanced by over twofold.Moreover,the evaluation of the MSTAR SAR dataset substantiates the algorithm's robustness and applicability in SAR denoising tasks,with a PSNR of 25.2021 being attained.These findings underscore the efficacy of the proposed algorithm in mitigating speckle noise while preserving critical features in SAR imagery,thereby enhancing its quality and usability in practical scenarios. 展开更多
关键词 SAR images image denoising residual networks adaptive activation function
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