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Acoustic physics-informed intelligent path planning framework for active sonar search
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作者 Siyuan Liao Wenbin Xiao +3 位作者 Yongxian Wang Zhao Sun Houwang Tu Wenfeng Liu 《Defence Technology(防务技术)》 2026年第1期354-376,共23页
In underwater target search path planning,the accuracy of sonar models directly dictates the accurate assessment of search coverage.In contrast to physics-informed sonar models,traditional geometric sonar models fail ... In underwater target search path planning,the accuracy of sonar models directly dictates the accurate assessment of search coverage.In contrast to physics-informed sonar models,traditional geometric sonar models fail to accurately characterize the complex influence of marine environments.To overcome these challenges,we propose an acoustic physics-informed intelligent path planning framework for underwater target search,integrating three core modules:The acoustic-physical modeling module adopts 3D ray-tracing theory and the active sonar equation to construct a physics-driven sonar detection model,explicitly accounting for environmental factors that influence sonar performance across heterogeneous spaces.The hybrid parallel computing module adopts a message passing interface(MPI)/open multi-processing(Open MP)hybrid strategy for large-scale acoustic simulations,combining computational domain decomposition and physics-intensive task acceleration.The search path optimization module adopts the covariance matrix adaptation evolution algorithm to solve continuous optimization problems of heading angles,which ensures maximum search coverage for targets.Largescale experiments conducted in the Pacific and Atlantic Oceans demonstrate the framework's effectiveness:(1)Precise capture of sonar detection range variations from 5.45 km to 50 km in heterogeneous marine environments.(2)Significant speedup of 453.43×for acoustic physics modeling through hybrid parallelization.(3)Notable improvements of 7.23%in detection coverage and 15.86%reduction in optimization time compared to the optimal baseline method.The framework provides a robust solution for underwater search missions in complex marine environments. 展开更多
关键词 Underwater target search Acoustic-physical modeling Hybrid parallel computing Covariance matrix adaptation evolution
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基于CS-BP-PID算法的烟叶密集烤房温度控制系统
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作者 沈少君 闫九福 +4 位作者 卢雨 林晓路 杜超凡 朱荣光 孟令峰 《农机化研究》 北大核心 2026年第4期95-102,共8页
烟叶烘烤作为决定烟叶品质的核心环节,其温湿度控制的精准性至关重要。针对当前密集烤房多阶段温度控制精度差、波动范围大、响应时间长等直接影响烟叶色泽、香气、化学成分、经济价值等问题,设计了一种基于布谷鸟算法(CS)优化的BP神经... 烟叶烘烤作为决定烟叶品质的核心环节,其温湿度控制的精准性至关重要。针对当前密集烤房多阶段温度控制精度差、波动范围大、响应时间长等直接影响烟叶色泽、香气、化学成分、经济价值等问题,设计了一种基于布谷鸟算法(CS)优化的BP神经网络PID控制器。通过模拟布谷鸟的寄生行为和莱维飞行特性,对BP神经网络的初始权重进行优化,加快了BP神经网络的自学习速度,以实现密集烤房温度的快速精准调控,降低了超调量,提高了响应速度。同时,基于树莓派4B搭建了密集烤房温湿度控制试验平台,并对控制器性能进行了验证。结果表明:CS-BP-PID控制器上升时间为79.35 s,峰值时间为180.00 s,调节时间为249.38 s,最大超调量为3.25%,相比常规PID控制器缩短了38.18%,调节时间缩短了47.05%,峰值时间和最大超调量减少了50%以上,满足系统温度控制需求。通过多阶段烟叶烘烤试验,上等烟比例提高了14.45%,经济效益得到了显著提升。该控制器综合性能优良,达到了精准控温控湿的效果。 展开更多
关键词 烟叶密集烤房 温度控制系统 cs-BP-PID算法
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计算机科学2.0(CS2.0)初探
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作者 李国杰 《计算》 2026年第1期5-5,共1页
经典的计算机科学(CS1.0)建立在一组长期未被系统反思的前提之上:1)计算是抽象符号操作;2)计算过程可被算法描述;3)物理实现是不影响计算本质的“载体”。然而,当代计算实践正在系统性地脱离这些基本假设,“算法+程序执行”已不再是对... 经典的计算机科学(CS1.0)建立在一组长期未被系统反思的前提之上:1)计算是抽象符号操作;2)计算过程可被算法描述;3)物理实现是不影响计算本质的“载体”。然而,当代计算实践正在系统性地脱离这些基本假设,“算法+程序执行”已不再是对计算的充分描述。AI大模型的内部表示是高维连续流形结构,没有稳定、可命名的语义对象,你无法说模型正在处理哪个符号、哪条信息,只能说它的状态正在向某个吸引子演化,这已经不是经典意义上的“信息处理”。如果计算机科学不能驾驭这种非离散、非符号、非算法的动力系统,在人工智能的浪潮中将逐渐被边缘化。 展开更多
关键词 经典计算机科学 cs2.0 cs1.0
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Elasticsearch在林业数据领域的应用 被引量:1
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作者 范晓磊 陈钊 高金萍 《世界林业研究》 北大核心 2025年第1期60-66,共7页
大数据技术的快速发展,为存储和处理海量林业数据带来了新机遇。Elasticsearch是一个分布式、高扩展和高实时性的搜索与数据分析引擎,在处理海量林业数据方面具有诸多优势。文中聚焦Elasticsearch的应用,从林业数据的存储与管理、统计... 大数据技术的快速发展,为存储和处理海量林业数据带来了新机遇。Elasticsearch是一个分布式、高扩展和高实时性的搜索与数据分析引擎,在处理海量林业数据方面具有诸多优势。文中聚焦Elasticsearch的应用,从林业数据的存储与管理、统计与分析及可视化3个角度进行综述。在存储管理方面,Elasticsearch以分布式架构和副本分片机制实现同时处理海量的林业结构化数据和非结构化数据,实现多源异构数据的统一存储;在统计分析方面,Elasticsearch借助Aggregation框架和Refresh机制对林业实时数据和历史数据进行统计与分析,为林业资源管理、生态环境监测和灾害预警与防控等提供决策依据;在可视化方面,Elasticsearch结合Kibana可通过静态数据的历史沉淀和动态数据的实时更新实现对林业数据的多维展示,能够直观展示林业资源的现状、变化趋势及各要素间的关系。最后,结合深度学习、地理信息系统、区块链等技术展望了Elasticsearch在林业图像处理与分析、空间数据深度分析以及数据安全与共享方面的应用前景。 展开更多
关键词 Elasticsearch搜索引擎 林业数据 数据管理 大数据
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中国湖沼沉积物中^(137)Cs时空变化特征及其对人类世的指示意义
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作者 邢伟 焦阳 +3 位作者 李想 张艺钊 李霄 鲍锟山 《地理科学》 北大核心 2026年第3期581-594,共14页
本研究收集整理了中国79个湖泊和沼泽沉积钻孔中^(137)Cs数据,探讨了其时空分布特征及其对人类世时限的指示意义。研究发现:(1)中国湖沼钻孔中^(137)Cs沉积记录普遍可以检测到1963年蓄积峰,该蓄积峰作为主计年时标层位清晰、易识别,具... 本研究收集整理了中国79个湖泊和沼泽沉积钻孔中^(137)Cs数据,探讨了其时空分布特征及其对人类世时限的指示意义。研究发现:(1)中国湖沼钻孔中^(137)Cs沉积记录普遍可以检测到1963年蓄积峰,该蓄积峰作为主计年时标层位清晰、易识别,具有明确的时标特征;沉积钻孔中1986年^(137)Cs蓄积峰可作为次级计年时标,但需要结合其它测年指标确认其可靠性;(2)中国湖沼钻孔中^(137)Cs记录存在显著的时空差异,受地形地貌、降水、径流侵蚀及人类活动等因素的影响,^(137)Cs比活度整体上由北向南递减,且在1960—1980年^(137)Cs比活度值达到最高水平;(3)中国1963年^(137)Cs主蓄积峰时标明确,是可靠的年代层标志,可作为潜在地层证据指示人类活动对区域环境的影响。 展开更多
关键词 ^(137)cs 时标 湖沼沉积 人类世 中国
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退火温度对三辊斜轧45CS/TA2复合管微观组织和力学性能的影响
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作者 任晏辰 牛辉 +3 位作者 付伦 季策 王涛 黄庆学 《塑性工程学报》 北大核心 2026年第1期245-255,共11页
针对三辊斜轧后的45CS/TA2复合管存在残余应力大、伸长率低的问题,研究了退火温度对其微观组织和力学性能的影响,目的是在保持良好抗拉强度和剪切强度的同时提升伸长率。结果表明,经550℃退火的45CS/TA2复合管综合性能最好:抗拉强度达到... 针对三辊斜轧后的45CS/TA2复合管存在残余应力大、伸长率低的问题,研究了退火温度对其微观组织和力学性能的影响,目的是在保持良好抗拉强度和剪切强度的同时提升伸长率。结果表明,经550℃退火的45CS/TA2复合管综合性能最好:抗拉强度达到595 MPa,剪切强度为275 MPa,伸长率为41%。微观分析表明,550℃退火后,界面形成了厚度适宜的TiC层,抵消了动态回复带来的不利影响,提升了界面结合强度。同时,钛侧轧制变形晶粒因退火转变为亚结构而使基体伸长率提升,基于强结合的异质金属在拉伸过程中持续协同变形效应,促使整体伸长率提升。而经650℃退火的复合管,由于TiC层过厚,导致界面结合强度下降,虽然钛侧发生了再结晶,但由于界面结合强度大幅下降,分层失效显著,导致伸长率提升并不明显。 展开更多
关键词 45cs/TA2复合管 三辊斜轧 界面微观结构 力学性能
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福建海域海产品中^(90)Sr和^(137)Cs的放射性水平及剂量评估
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作者 柯思因 钟强强 +6 位作者 张福乐 李聪 宾丽 陈越 吴镇 黄德坤 于涛 《海洋环境科学》 北大核心 2026年第1期25-33,共9页
2023年8月日本福岛核污染水排海引发公众对海产品安全的担忧。本研究通过分析2024年福建海域海产品中人工放射性核素^(90)Sr和^(137)Cs的比活度,系统评估我国近海海产品放射性本底水平。全样分析的结果表明,海产品中^(90)Sr和^(137)Cs... 2023年8月日本福岛核污染水排海引发公众对海产品安全的担忧。本研究通过分析2024年福建海域海产品中人工放射性核素^(90)Sr和^(137)Cs的比活度,系统评估我国近海海产品放射性本底水平。全样分析的结果表明,海产品中^(90)Sr和^(137)Cs的比活度范围分别为<0.004~0.155 Bq/kg和0.006~0.132 Bq/kg(鲜重);将海产品分为可食部分和不可食部分并进一步分析发现,^(137)Cs更易富集于肌肉组织等可食部分,而^(90)Sr倾向富集在骨骼等不可食部分。总体而言,福建海域海产品中^(137)Cs比活度水平与我国山东等邻近海域相当,远低于福岛附近海域。本文评估了居民因食用海产品而摄入^(90)Sr和^(137)Cs所致的年待积有效剂量分别为0.0051μSv/a和0.0062μSv/a,约为全球自然本底辐射(2.4 mSv/a)的0.25‰。本研究为评估核污染水排放对福建海域的后续影响提供了基础数据支撑。 展开更多
关键词 福岛核污染水 ^(90)Sr ^(137)cs 海产品 剂量评估
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QHF-CS: Quantum-Enhanced Heart Failure Prediction Using Quantum CNN with Optimized Feature Qubit Selection with Cuckoo Search in Skewed Clinical Data
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作者 Prasanna Kottapalle Tan Kuan Tak +2 位作者 Pravin Ramdas Kshirsagar Gopichand Ginnela Vijaya Krishna Akula 《Computers, Materials & Continua》 2025年第8期3857-3892,共36页
Heart failure prediction is crucial as cardiovascular diseases become the leading cause of death worldwide,exacerbated by the COVID-19 pandemic.Age,cholesterol,and blood pressure datasets are becoming inadequate becau... Heart failure prediction is crucial as cardiovascular diseases become the leading cause of death worldwide,exacerbated by the COVID-19 pandemic.Age,cholesterol,and blood pressure datasets are becoming inadequate because they cannot capture the complexity of emerging health indicators.These high-dimensional and heterogeneous datasets make traditional machine learning methods difficult,and Skewness and other new biomarkers and psychosocial factors bias the model’s heart health prediction across diverse patient profiles.Modern medical datasets’complexity and high dimensionality challenge traditional predictionmodels like SupportVectorMachines and Decision Trees.Quantum approaches include QSVM,QkNN,QDT,and others.These Constraints drove research.The“QHF-CS:Quantum-Enhanced Heart Failure Prediction using Quantum CNN with Optimized Feature Qubit Selection with Cuckoo Search in Skewed Clinical Data”system was developed in this research.This novel system leverages a Quantum Convolutional Neural Network(QCNN)-based quantum circuit,enhanced by meta-heuristic algorithms—Cuckoo SearchOptimization(CSO),Artificial BeeColony(ABC),and Particle SwarmOptimization(PSO)—for feature qubit selection.Among these,CSO demonstrated superior performance by consistently identifying the most optimal and least skewed feature subsets,which were then encoded into quantum states for circuit construction.By integrating advanced quantum circuit feature maps like ZZFeatureMap,RealAmplitudes,and EfficientSU2,the QHF-CS model efficiently processes complex,high-dimensional data,capturing intricate patterns that classical models overlook.The QHF-CS model improves precision,recall,F1-score,and accuracy to 0.94,0.95,0.94,and 0.94.Quantum computing could revolutionize heart failure diagnostics by improving model accuracy and computational efficiency,enabling complex healthcare diagnostic breakthroughs. 展开更多
关键词 Accuracy quantum machine learning heart failure PREDICTION cuckoo search optimization(csO) skewed clinical data quantum convolutional circuit
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A Robot Grasp Detection Method Based on Neural Architecture Search and Its Interpretability Analysis
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作者 Lu Rong Manyu Xu +5 位作者 Wenbo Zhu Zhihao Yang Chao Dong Yunzhi Zhang Kai Wang Bing Zheng 《Computers, Materials & Continua》 2026年第4期1282-1306,共25页
Deep learning has become integral to robotics,particularly in tasks such as robotic grasping,where objects often exhibit diverse shapes,textures,and physical properties.In robotic grasping tasks,due to the diverse cha... Deep learning has become integral to robotics,particularly in tasks such as robotic grasping,where objects often exhibit diverse shapes,textures,and physical properties.In robotic grasping tasks,due to the diverse characteristics of the targets,frequent adjustments to the network architecture and parameters are required to avoid a decrease in model accuracy,which presents a significant challenge for non-experts.Neural Architecture Search(NAS)provides a compelling method through the automated generation of network architectures,enabling the discovery of models that achieve high accuracy through efficient search algorithms.Compared to manually designed networks,NAS methods can significantly reduce design costs,time expenditure,and improve model performance.However,such methods often involve complex topological connections,and these redundant structures can severely reduce computational efficiency.To overcome this challenge,this work puts forward a robotic grasp detection framework founded on NAS.The method automatically designs a lightweight network with high accuracy and low topological complexity,effectively adapting to the target object to generate the optimal grasp pose,thereby significantly improving the success rate of robotic grasping.Additionally,we use Class Activation Mapping(CAM)as an interpretability tool,which captures sensitive information during the perception process through visualized results.The searched model achieved competitive,and in some cases superior,performance on the Cornell and Jacquard public datasets,achieving accuracies of 98.3%and 96.8%,respectively,while sustaining a detection speed of 89 frames per second with only 0.41 million parameters.To further validate its effectiveness beyond benchmark evaluations,we conducted real-world grasping experiments on a UR5 robotic arm,where the model demonstrated reliable performance across diverse objects and high grasp success rates,thereby confirming its practical applicability in robotic manipulation tasks. 展开更多
关键词 Robotics grasping detection neural architecture search neural network interpretability
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Segment-Conditioned Latent-Intent Framework for Cooperative Multi-UAV Search
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作者 Gang Hou Aifeng Liu +4 位作者 Tao Zhao Wenyuan Wei Bo Li Jiancheng Liu Siwen Wei 《Computers, Materials & Continua》 2026年第4期2286-2301,共16页
Cooperative multi-UAV search requires jointly optimizing wide-area coverage,rapid target discovery,and endurance under sensing and motion constraints.Resolving this coupling enables scalable coordination with high dat... Cooperative multi-UAV search requires jointly optimizing wide-area coverage,rapid target discovery,and endurance under sensing and motion constraints.Resolving this coupling enables scalable coordination with high data efficiency and mission reliability.We formulate this problem as a discounted Markov decision process on an occupancy grid with a cellwise Bayesian belief update,yielding a Markov state that couples agent poses with a probabilistic target field.On this belief–MDP we introduce a segment-conditioned latent-intent framework,in which a discrete intent head selects a latent skill every K steps and an intra-segment GRU policy generates per-step control conditioned on the fixed intent;both components are trained end-to-end with proximal updates under a centralized critic.On the 50×50 grid,coverage and discovery convergence times are reduced by up to 48%and 40%relative to a flat actor-critic benchmark,and the aggregated convergence metric improves by about 12%compared with a stateof-the-art hierarchical method.Qualitative analyses further reveal stable spatial sectorization,low path overlap,and fuel-aware patrolling,indicating that segment-conditioned latent intents provide an effective and scalable mechanism for coordinated multi-UAV search. 展开更多
关键词 Multi-agent reinforcement learning Markov decision process multi-UAV cooperative search
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Research on Beam Peak Search Reduction for 5G mm-Wave OTA Testing
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作者 An Xudong Yin Mengru +2 位作者 Li Wenyu Qu Meijun Sun Siyang 《China Communications》 2026年第1期1-9,共9页
For 5G millimeter wave(mm-Wave)user equipments(UEs),all test cases must be evaluated in Over-The-Air(OTA)manner.Test time increases dramatically compared to Sub-6 GHz.Therefore,test time reduction is of great signific... For 5G millimeter wave(mm-Wave)user equipments(UEs),all test cases must be evaluated in Over-The-Air(OTA)manner.Test time increases dramatically compared to Sub-6 GHz.Therefore,test time reduction is of great significance for 5G mm-Wave OTA testing.Among all test cases,beam peak search is the most time-consuming,taking up the majority of the overall test time.Therefore,the objective of this work is to determine a suitable beam peak search grid for 5G mm-Wave UEs with satisfactory accuracy and efficiency.Through radiation property investigation of 5G mm-Wave commercial UEs,more reasonable reference array configuration(4×2)and reference deployment scenario(composite beam)are proposed for beam peak search grid analysis.The effect of different grid configurations on beam peak search precision are characterized quantitatively.The determination of associated measurement uncertainty(MU)term along with quantitative analysis approach are proposed based on statistical analysis.Finally,the recommended minimum number of beam peak search grid points is 182 based on the proposed 4×2 array under composite beam scenario.Compared with currently-required 1106 points in 3GPP/CTIA specifications,over 80%reduction can be achieved without increasing the MU limit.The feasibility of the proposed MU analysis as well as the recommended grids is demonstrated through measurements. 展开更多
关键词 beam peak search composite beam 5G mm-Wave measurement grid MU OTA
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Improved Cuckoo Search Algorithm for Engineering Optimization Problems
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作者 Shao-Qiang Ye Azlan Mohd Zain Yusliza Yusoff 《Computers, Materials & Continua》 2026年第4期1607-1631,共25页
Engineering optimization problems are often characterized by high dimensionality,constraints,and complex,multimodal landscapes.Traditional deterministic methods frequently struggle under such conditions,prompting incr... Engineering optimization problems are often characterized by high dimensionality,constraints,and complex,multimodal landscapes.Traditional deterministic methods frequently struggle under such conditions,prompting increased interest in swarm intelligence algorithms.Among these,the Cuckoo Search(CS)algorithm stands out for its promising global search capabilities.However,it often suffers from premature convergence when tackling complex problems.To address this limitation,this paper proposes a Grouped Dynamic Adaptive CS(GDACS)algorithm.Theenhancements incorporated intoGDACS can be summarized into two key aspects.Firstly,a chaotic map is employed to generate initial solutions,leveraging the inherent randomness of chaotic sequences to ensure a more uniform distribution across the search space and enhance population diversity from the outset.Secondly,Cauchy and Levy strategies replace the standard CS population update.This strategy involves evaluating the fitness of candidate solutions to dynamically group the population based on performance.Different step-size adaptation strategies are then applied to distinct groups,enabling an adaptive search mechanism that balances exploration and exploitation.Experiments were conducted on six benchmark functions and four constrained engineering design problems,and the results indicate that the proposed GDACS achieves good search efficiency and produces more accurate optimization results compared with other state-of-the-art algorithms. 展开更多
关键词 Cuckoo search algorithm chaotic transformation population division adaptive update strategy Cauchy distribution
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Optimizing RPL Routing Using Tabu Search to Improve Link Stability and Energy Consumption in IoT Networks
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作者 Mehran Tarif Mohammadhossein Homaei +1 位作者 Abbas Mirzaei Babak Nouri-Moghaddam 《Computers, Materials & Continua》 2026年第4期2095-2126,共32页
The Routing Protocol for Low-power and Lossy Networks(RPL)is widely used in Internet of Things(IoT)systems,where devices usually have very limited resources.However,RPL still faces several problems,such as high energy... The Routing Protocol for Low-power and Lossy Networks(RPL)is widely used in Internet of Things(IoT)systems,where devices usually have very limited resources.However,RPL still faces several problems,such as high energy usage,unstable links,and inefficient routing decisions,which reduce the overall network performance and lifetime.In this work,we introduce TABURPL,an improved routing method that applies Tabu Search(TS)to optimize the parent selection process.The method uses a combined cost function that considers Residual Energy,Transmission Energy,Distance to the Sink,Hop Count,Expected Transmission Count(ETX),and Link Stability Rate(LSR).Simulation results show that TABURPL improves link stability,lowers energy consumption,and increases the packet delivery ratio compared with standard RPL and other existing approaches.These results indicate that Tabu Search can handle the complex trade-offs in IoT routing and can provide a more reliable solution for extending the network lifetime. 展开更多
关键词 Internet of things RPL protocol tabu search energy efficiency link stability multi-metric routing
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h-BN载体对Cs-Ru/h-BN催化合成氨性能的影响
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作者 高超 江显灿 +4 位作者 杨阳 方智霖 张鹏 黄佳 姚林利 《低碳化学与化工》 北大核心 2026年第1期141-149,共9页
NH_(3)是一种重要的无机化工原料,也是一种理想的氢能载体。Ru基催化剂因其在低温低压下具有优于传统铁基催化剂的催化性能而备受关注。以4种商业六方氮化硼(h-BN)为载体负载Ru和助剂CsNO_(3),制备了x Cs-Ru/h-BN(x=n(Cs)/n(Ru))催化剂... NH_(3)是一种重要的无机化工原料,也是一种理想的氢能载体。Ru基催化剂因其在低温低压下具有优于传统铁基催化剂的催化性能而备受关注。以4种商业六方氮化硼(h-BN)为载体负载Ru和助剂CsNO_(3),制备了x Cs-Ru/h-BN(x=n(Cs)/n(Ru))催化剂。采用XRD、SEM、N_(2)吸/脱附、H_(2)-TPR和XPS等对载体和催化剂的理化性质进行了表征,考察了温和反应条件下催化剂的催化性能,并利用动力学分析了N_(2)、H_(2)和NH_(3)的反应级数。结果表明,2Cs-Ru/h-BN-1表面Ru具有更高活性,能降低CsNO_(3)分解和还原的温度,有利于Ru表面N_(2)分子解离。动力学分析表明,2Cs-Ru/h-BN-1的H_(2)反应级数为正,说明催化剂表面解离的氢原子更易迁移转化,这不仅能抑制催化剂氢中毒并稳定合成氨,还能释放出更多活性位点用于N_(2)分子解离。在400℃、0.1 MPa和合成气流速60 mL/min(V(H_(2)):V(N_(2))=3:1)的条件下反应1 h,2Cs-Ru/h-BN-1的合成氨速率(以每克催化剂计)为3902μmol/(g·h),且该催化剂可稳定运行48 h。 展开更多
关键词 六方氮化硼 cs-Ru/h-BN催化剂 合成氨 氢中毒
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Optimization of the frequency offset increment of FDA-MIMO based on cuckoo search algorithm
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作者 WANG Bo ZHAO Yu +2 位作者 LI Yonglin YANG Rennong XUE Junjie 《Journal of Systems Engineering and Electronics》 2026年第1期157-170,共14页
Frequency diverse array multiple-input multiple-output(FDA-MIMO)radar has gained considerable research attention due to its ability to effectively counter active repeater deception jamming in complex electromagnetic e... Frequency diverse array multiple-input multiple-output(FDA-MIMO)radar has gained considerable research attention due to its ability to effectively counter active repeater deception jamming in complex electromagnetic environments.The effectiveness of interference suppression by FDA-MIMO is limited by the inherent range-angle coupling issue in the FDA beampattern.Existing literature primarily focuses on control methods for FDA-MIMO radar beam direction under the assumption of static beampatterns,with insufficient exploration of techniques for managing nonstationary beam directions.To address this gap,this paper initially introduces the FDA-MIMO signal model and the calculation formula for the FDA-MIMO array output using the minimum variance distortionless response(MVDR)beamformer.Building on this,the problem of determining the optimal frequency offset for the FDA is rephrased as a convex optimization problem,which is then resolved using the cuckoo search(CS)algorithm.Simulations confirm the effectiveness of the proposed approach,showing that the frequency offsets obtained through the CS algorithm can create a dot-shaped beam direction at the target location while effectively suppressing interference signals within the mainlobe. 展开更多
关键词 frequency diverse array multiple-input multiple-output(FDA-MIMO) convex optimization cuckoo search algorithm beampattern
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2017年长安CS95 TF-81SC变速器前进挡冲击
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作者 商爱鹏 《汽车维修技师》 2026年第3期102-104,共3页
车型:2017年长安CS95,配置2.0L涡轮增压发动机、TF-81SC 6前速自动变速器。行驶里程:240000km。故障现象:客户反馈车辆挂前进挡时冲击过大。故障诊断:接车后,第一步先确认故障现象。通过路试车辆发现,在冷车状态下,车辆入前进挡时有轻... 车型:2017年长安CS95,配置2.0L涡轮增压发动机、TF-81SC 6前速自动变速器。行驶里程:240000km。故障现象:客户反馈车辆挂前进挡时冲击过大。故障诊断:接车后,第一步先确认故障现象。通过路试车辆发现,在冷车状态下,车辆入前进挡时有轻微冲击;行驶过程中,各挡位尤其是低挡位区间的升降挡状况不佳,存在明显顿挫感。待车辆热车后,各挡位升降挡情况处于可接受范围,但进入前进挡的冲击明显增大。接着读取变速器控制模块内的故障码,结果显示并无故障码设置。考虑到该车行驶里程较长且保养状况不理想,变速器油特别脏,因此建议客户进行变速器大修。 展开更多
关键词 前进挡冲击 TF-81SC变速器 长安cs95
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AquaTree:Deep Reinforcement Learning-Driven Monte Carlo Tree Search for Underwater Image Enhancement
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作者 Chao Li Jianing Wang +1 位作者 Caichang Ding Zhiwei Ye 《Computers, Materials & Continua》 2026年第3期1444-1464,共21页
Underwater images frequently suffer from chromatic distortion,blurred details,and low contrast,posing significant challenges for enhancement.This paper introduces AquaTree,a novel underwater image enhancement(UIE)meth... Underwater images frequently suffer from chromatic distortion,blurred details,and low contrast,posing significant challenges for enhancement.This paper introduces AquaTree,a novel underwater image enhancement(UIE)method that reformulates the task as a Markov Decision Process(MDP)through the integration of Monte Carlo Tree Search(MCTS)and deep reinforcement learning(DRL).The framework employs an action space of 25 enhancement operators,strategically grouped for basic attribute adjustment,color component balance,correction,and deblurring.Exploration within MCTS is guided by a dual-branch convolutional network,enabling intelligent sequential operator selection.Our core contributions include:(1)a multimodal state representation combining CIELab color histograms with deep perceptual features,(2)a dual-objective reward mechanism optimizing chromatic fidelity and perceptual consistency,and(3)an alternating training strategy co-optimizing enhancement sequences and network parameters.We further propose two inference schemes:an MCTS-based approach prioritizing accuracy at higher computational cost,and an efficient network policy enabling real-time processing with minimal quality loss.Comprehensive evaluations on the UIEB Dataset and Color correction and haze removal comparisons on the U45 Dataset demonstrate AquaTree’s superiority,significantly outperforming nine state-of-the-art methods across five established underwater image quality metrics. 展开更多
关键词 Underwater image enhancement(UIE) Monte Carlo tree search(MCTS) deep reinforcement learning(DRL) Markov decision process(MDP)
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基于CSSOA-DSRF模型的致密砂岩储层流体测井智能识别
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作者 展硕硕 李可赛 +5 位作者 刘岩 林行杰 雷铠铖 郑明明 刘彦君 冯国栋 《测井技术》 2026年第1期108-120,共13页
储层流体识别对致密砂岩油气藏评价和开发具有重要意义。致密砂岩储层具有低孔隙度低渗透率、非均质性强等特点,导致气水关系复杂。传统的储层流体识别方法主要依赖电阻率测井等数据,对于导电性对比度不强的储层流体识别困难。随着机器... 储层流体识别对致密砂岩油气藏评价和开发具有重要意义。致密砂岩储层具有低孔隙度低渗透率、非均质性强等特点,导致气水关系复杂。传统的储层流体识别方法主要依赖电阻率测井等数据,对于导电性对比度不强的储层流体识别困难。随着机器学习、人工智能技术的发展,测井技术与智能算法耦合在流体识别中发挥了关键性的作用。然而传统机器学习模型对重复度高、类间不平衡的样本缺乏区分能力,预测能力受限。提出一种基于混沌麻雀搜索算法-双重代价敏感随机森林(Chaos Sparrow Search Optimization Algorithm-Double Cost Sensitive Random Forest,CSSOA-DSRF)模型的致密砂岩储层流体测井智能识别方法。双重代价敏感随机森林(Double Cost Sensitive Random Forest,DSRF)在随机森林算法的特征选择阶段和集成投票阶段引入代价敏感学习,通过为不同流体类型分配权重系数,增强了模型对少数类样本的关注,使得特征选择更有针对性,从而选出对少数类数据更敏感的决策树集合,解决了样本类别不平衡问题。为克服传统优化方法易陷入局部最优的局限,混沌麻雀搜索算法(Chaos Sparrow Search Optimization Algorithm,CSSOA)在麻雀搜索算法(Sparrow Search Algorithm,SSA)的框架上融入改进的Tent混沌映射与高斯变异机制,提升了种群多样性与全局搜索能力,降低早收敛风险。该模型结合研究区声波时差测井、补偿中子测井、密度测井、自然伽马测井、深侧向电阻率测井这5条测井响应特征曲线输入和输出对应的流体类型预测结果。通过对照射孔结论预测准确率达到90.46%,并与DSRF、随机森林(Random Forest,RF)、K近邻算法(K-Nearest Neighbors,KNN)和支持向量机(Support Vector Machine,SVM)进行对比,该方法准确率高,保持了较好的鲁棒性和稳定性,可为致密砂岩储层流体识别提供一种可行方案。 展开更多
关键词 致密砂岩 机器学习 随机森林 支持向量机 麻雀搜索算法 遗传算法 决策树 种群
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基于SCSSA-CNN-BiLSTM神经网络的厌氧发酵产气预测
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作者 甄箫斐 焦若楠 +1 位作者 董樾洋 詹寒 《环境工程技术学报》 北大核心 2026年第1期279-289,共11页
厌氧发酵作为一种高效的有机废物处理技术,能够将农业废物转化为沼气,实现资源的循环利用和能源的可持续供应。厌氧发酵过程受到反应底物碳氮比、pH、挥发性脂肪酸、氨氮浓度以及化学需氧量等因素的影响。为探究厌氧发酵的规律,进行混... 厌氧发酵作为一种高效的有机废物处理技术,能够将农业废物转化为沼气,实现资源的循环利用和能源的可持续供应。厌氧发酵过程受到反应底物碳氮比、pH、挥发性脂肪酸、氨氮浓度以及化学需氧量等因素的影响。为探究厌氧发酵的规律,进行混合原料厌氧发酵产气实验,反应底物中牛粪与玉米秸秆的配比分别为1:1、2:1、3:1,设置3组平行实验,以确保实验结果的可靠性和可重复性。创建了正余弦与柯西变异策略优化的麻雀搜索算法(SCSSA),并将其对卷积双向记忆神经网络(CNNBiLSTM)的超参数进行优化,选择反应时间、牛粪与玉米秸秆配比、pH、挥发性脂肪酸、氨氮浓度以及化学需氧量作为模型的输入参数,日产气量和日甲烷产量作为输出参数。结果表明,牛粪与玉米秸秆配比为3:1时,甲烷产量最多,配比1:1实验组次之,配比2:1实验组最小。基于SCSSA-CNN-BiLSTM混合原料厌氧发酵产气预测模型的日产气量准确率达95.29%,日甲烷产量准确率达95.87%,拟合优度(R^(2))达到了0.972。本研究解决了传统麻雀搜索算法模型易过早收敛导致陷入局部最优的问题,并提高了全局搜索能力,为实际实验提供了依据。 展开更多
关键词 牛粪 玉米秸秆 厌氧发酵 神经网络 麻雀搜索算法 产气预测
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基于ElasticSearch的TEE病例库检索系统设计与实现 被引量:17
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作者 胡鑫 姚宇 徐英杰 《计算机应用》 CSCD 北大核心 2018年第A01期91-94,共4页
为了解决大数据量下的"经食道超声电子病例库系统"中搜索服务的搜索效率低、匹配度单一等问题,设计并构建了一种以Elastic Search技术为核心,结合Nginx、Spring Boot、Redis等多门技术的分布式经食道超声检索系统。该系统属... 为了解决大数据量下的"经食道超声电子病例库系统"中搜索服务的搜索效率低、匹配度单一等问题,设计并构建了一种以Elastic Search技术为核心,结合Nginx、Spring Boot、Redis等多门技术的分布式经食道超声检索系统。该系统属于一个微服务,首先由Logstash工具将旧数据从MySQL导入到Elastic Search中,再由Spring Boot管理用户与Elastic Search数据之间的访问与存储,Nginx服务器管理静态资源图片和视频,Redis管理用户信息及常用访问内容。经大量测试表明,该系统搜索结果齐全,包含了病例数据、图片、视频等各类信息;搜索响应时间较短,平均在2 s以内。因此,用该微服务来替换原有经食道超声电子病例库系统中的搜索功能,可大大提高病例库系统的性能。 展开更多
关键词 Elasticsearch 搜索引擎 分布式检索 springBoot NGINX REDIS
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