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A Class of Parallel Algorithm for Solving Low-rank Tensor Completion
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作者 LIU Tingyan WEN Ruiping 《应用数学》 北大核心 2025年第4期1134-1144,共11页
In this paper,we established a class of parallel algorithm for solving low-rank tensor completion problem.The main idea is that N singular value decompositions are implemented in N different processors for each slice ... In this paper,we established a class of parallel algorithm for solving low-rank tensor completion problem.The main idea is that N singular value decompositions are implemented in N different processors for each slice matrix under unfold operator,and then the fold operator is used to form the next iteration tensor such that the computing time can be decreased.In theory,we analyze the global convergence of the algorithm.In numerical experiment,the simulation data and real image inpainting are carried out.Experiment results show the parallel algorithm outperform its original algorithm in CPU times under the same precision. 展开更多
关键词 Tensor completion Low-rank CONVERGENCE parallel algorithm
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A Class of Parallel Algorithms of Real-TimeNumerical Simulation for Stiff Dynamic System 被引量:2
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作者 Cao Xuenian Liu Degui Li Shoufu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第4期51-58,共8页
In this paper a class of real-time parallel modified Rosenbrock methods of numerical simulation is constructed for stiff dynamic systems on a multiprocessor system, and convergence and numerical stability of these met... In this paper a class of real-time parallel modified Rosenbrock methods of numerical simulation is constructed for stiff dynamic systems on a multiprocessor system, and convergence and numerical stability of these methods are discussed. A-stable real-time parallel formula of two-stage third-order and A(α)-stable real-time parallel formula with o ≈ 89.96° of three-stage fourth-order are particularly given. The numerical simulation experiments in parallel environment show that the class of algorithms is efficient and applicable, with greater speedup. 展开更多
关键词 Dynamic system Real-time simulation parallel algorithms?
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Lower Bounds and a Nearly Fastest General Parallel Branch-and-Bound Algorithm 被引量:2
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作者 Wu, Jigang Xie, Xing +1 位作者 Wan, Yingyu Chen, Guoliang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第3期65-73,共9页
In this paper, it is supposed that the B&B algorithm finds the first optimal solution after h nodes have been expanded and m active nodes have been created in the state-space tree. Then the lower bound Ω(m+h log ... In this paper, it is supposed that the B&B algorithm finds the first optimal solution after h nodes have been expanded and m active nodes have been created in the state-space tree. Then the lower bound Ω(m+h log h) of the running time for the general sequential B&B algorithm and the lower bound Ω(m/p+h log p) for the general parallel best-first B&B algorithm in PRAM-CREW are proposed, where p is the number of processors available. Moreover, the lower bound Ω(M/p+H+(H/p) log (H/p)) is presented for the parallel algorithms on distributed memory system, where M and H represent total number of the active nodes and that of the expanded nodes processed by p processors, respectively. In addition, a nearly fastest general parallel best-first B&B algorithm is put forward. The parallel algorithm is the fastest one as p = max{hε, r}, where ε = 1/ rootlogh, and r is the largest branch number of the nodes in the state-space tree. 展开更多
关键词 BRANCH-AND-BOUND State-space tree Active list parallel algorithm Combinatorial search.
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Efficient parallel adaptive array beamforming algorithm
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作者 Huang Fei Sheng Weixing Ma Xiaofeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1221-1226,共6页
For a large-scale adaptive array,the heavy computational load and the high-rate data transmission are two challenges in the implementation of an adaptive digital beamforming system.An efficient parallel digital beamfo... For a large-scale adaptive array,the heavy computational load and the high-rate data transmission are two challenges in the implementation of an adaptive digital beamforming system.An efficient parallel digital beamforming(DBF)algorithm based on the least mean square algorithm(PLMS)is proposed.An appropriate method is found to partition the least mean square(LMS)algorithm into a number of operational modules,which can be easily executed in a distributed-parallel-processing fashion.As a result,the proposed PLMS algorithm provides an effective solution that can alleviate the bottleneck of high-rate data transmission and reduce the computational cost.PLMS requires less computational load than that of the conventional parallel algorithms based on the recursive least square(RLS)algorithm,as well as it is easier to be implemented to do real time adaptive array processing.Moreover,low sidelobe of the beam pattern is obtained by constraining the static steering vector with Tschebyscheff coefficients.Finally,a scheme of the PLMS algorithm using distributed-parallel-processing system is also proposed.The simulation results demonstrate that the PLMS algorithm has the same interference cancellation performance as that of the conventional LMS algorithm.Moreover,the PLMS algorithm can obtain the same good beamforming performance,regardless how the algorithm is partitioned.It is expected that the proposed algorithm will be used in a large-scale adaptive array system to deal with real time adaptive digital beamforming processing. 展开更多
关键词 adaptive digital beamforming parallel algorithm least mean square generalized sidelobe canceller.
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Chaotic migration-based pseudo parallel genetic algorithm and its application in inventory optimization 被引量:1
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作者 ChenXiaofang GuiWeihua WangYalin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期411-417,共7页
Considering premature convergence in the searching process of genetic algorithm, a chaotic migration-based pseudo parallel genetic algorithm (CMPPGA) is proposed, which applies the idea of isolated evolution and infor... Considering premature convergence in the searching process of genetic algorithm, a chaotic migration-based pseudo parallel genetic algorithm (CMPPGA) is proposed, which applies the idea of isolated evolution and information exchanging in distributed Parallel Genetic Algorithm by serial program structure to solve optimization problem of low real-time demand. In this algorithm, asynchronic migration of individuals during parallel evolution is guided by a chaotic migration sequence. Information exchanging among sub-populations is ensured to be efficient and sufficient due to that the sequence is ergodic and stochastic. Simulation study of CMPPGA shows its strong global search ability, superiority to standard genetic algorithm and high immunity against premature convergence. According to the practice of raw material supply, an inventory programming model is set up and solved by CMPPGA with satisfactory results returned. 展开更多
关键词 parallel genetic algorithm CHAOS premature convergence inventory optimization.
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General and efficient parallel approach of finite element-boundary integral-multilevel fast multipole algorithm 被引量:3
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作者 Pan Xiaomin Sheng Xinqing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期207-212,共6页
A general and efficient parallel approach is proposed for the first time to parallelize the hybrid finiteelement-boundary-integral-multi-level fast multipole algorithm (FE-BI-MLFMA). Among many algorithms of FE-BI-M... A general and efficient parallel approach is proposed for the first time to parallelize the hybrid finiteelement-boundary-integral-multi-level fast multipole algorithm (FE-BI-MLFMA). Among many algorithms of FE-BI-MLFMA, the decomposition algorithm (DA) is chosen as a basis for the parallelization of FE-BI-MLFMA because of its distinct numerical characteristics suitable for parallelization. On the basis of the DA, the parallelization of FE-BI-MLFMA is carried out by employing the parallelized multi-frontal method for the matrix from the finiteelement method and the parallelized MLFMA for the matrix from the boundary integral method respectively. The programming and numerical experiments of the proposed parallel approach are carried out in the high perfor- mance computing platform CEMS-Liuhui. Numerical experiments demonstrate that FE-BI-MLFMA is efficiently parallelized and its computational capacity is greatly improved without losing accuracy, efficiency, and generality. 展开更多
关键词 finite element-boundary integral-multilevel fast multipole algorithm parallelization.
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Approximation algorithm for multiprocessor parallel job scheduling 被引量:1
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作者 陈松乔 黄金贵 陈建二 《Journal of Central South University of Technology》 2002年第4期267-272,共6页
P k |fix| C max problem is a new scheduling problem based on the multiprocessor parallel job, and it is proved to be NP hard problem when k ≥3. This paper focuses on the case of k =3. Some new observations and new te... P k |fix| C max problem is a new scheduling problem based on the multiprocessor parallel job, and it is proved to be NP hard problem when k ≥3. This paper focuses on the case of k =3. Some new observations and new techniques for P 3 |fix| C max problem are offered. The concept of semi normal schedulings is introduced, and a very simple linear time algorithm Semi normal Algorithm for constructing semi normal schedulings is developed. With the method of the classical Graham List Scheduling, a thorough analysis of the optimal scheduling on a special instance is provided, which shows that the algorithm is an approximation algorithm of ratio of 9/8 for any instance of P 3|fix| C max problem, and improves the previous best ratio of 7/6 by M.X.Goemans. 展开更多
关键词 MULTIPROCESSOR parallel JOB SCHEDULING APPROXIMATION algorithm NP-HARD problem
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Improvement and performance of parallel multilevel fast multipole algorithm 被引量:16
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作者 Zhanhe Liu Peilin Huang +1 位作者 Zhe Wu Xu Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第1期164-169,共6页
The method of establishing data structures plays an important role in the efficiency of parallel multilevel fast multipole algorithm(PMLFMA).Considering the main complements of multilevel fast multipole algorithm(M... The method of establishing data structures plays an important role in the efficiency of parallel multilevel fast multipole algorithm(PMLFMA).Considering the main complements of multilevel fast multipole algorithm(MLFMA) memory,a new parallelization strategy and a modified data octree construction scheme are proposed to further reduce communication in order to improve parallel efficiency.For far interaction,a new scheme called dynamic memory allocation is developed.To analyze the workload balancing performance of a parallel implementation,the original concept of workload balancing factor is introduced and verified by numerical examples.Numerical results show that the above measures improve the parallel efficiency and are suitable for the analysis of electrical large-scale scattering objects. 展开更多
关键词 multilevel fast multipole algorithm(MLFMA) electromagnetic scattering parallelIZATION radar cross section(RCS).
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Parallel discrete lion swarm optimization algorithm for solving traveling salesman problem 被引量:4
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作者 ZHANG Daoqing JIANG Mingyan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期751-760,共10页
As a typical representative of the NP-complete problem, the traveling salesman problem(TSP) is widely utilized in computer networks, logistics distribution, and other fields. In this paper, a discrete lion swarm optim... As a typical representative of the NP-complete problem, the traveling salesman problem(TSP) is widely utilized in computer networks, logistics distribution, and other fields. In this paper, a discrete lion swarm optimization(DLSO) algorithm is proposed to solve the TSP. Firstly, we introduce discrete coding and order crossover operators in DLSO. Secondly, we use the complete 2-opt(C2-opt) algorithm to enhance the local search ability.Then in order to enhance the efficiency of the algorithm, a parallel discrete lion swarm optimization(PDLSO) algorithm is proposed.The PDLSO has multiple populations, and each sub-population independently runs the DLSO algorithm in parallel. We use the ring topology to transfer information between sub-populations. Experiments on some benchmarks TSP problems show that the DLSO algorithm has a better accuracy than other algorithms, and the PDLSO algorithm can effectively shorten the running time. 展开更多
关键词 discrete lion swarm optimization(DLSO)algorithm complete 2-opt(C2-opt)algorithm parallel discrete lion swarm optimization(PDLSO)algorithm traveling salesman problem(TSP)
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Improved Hungarian algorithm for assignment problems of serial-parallel systems 被引量:5
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作者 Tingpeng Li Yue Li Yanling Qian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期858-870,共13页
In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used t... In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used to solve the assignment problem of serial-parallel systems. First of all, by replacing parallel jobs with virtual jobs, the proposed algorithm converts the serial-parallel system into a pure serial system, where the classical Hungarian algorithm can be used to generate a temporal assignment plan via optimization. Afterwards, the assignment plan is validated by checking whether the virtual jobs can be realized by real jobs through local searching. If the assignment plan is not valid, the converted system will be adapted by adjusting the parameters of virtual jobs, and then be optimized again. Through iterative searching, the valid optimal assignment plan can eventually be obtained.To evaluate the proposed algorithm, the valid optimal assignment plan is applied to labor allocation of a manufacturing system which is a typical serial-parallel system. 展开更多
关键词 Hungarian algorithm assignment problem virtual job serial-parallel system optimization
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Concise review of relaxations and approximation algorithms for nonidentical parallel-machine scheduling to minimize total weighted completion times 被引量:1
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作者 Li Kai Yang Shanlin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期827-834,共8页
A class of nonidentical parallel machine scheduling problems are considered in which the goal is to minimize the total weighted completion time. Models and relaxations are collected. Most of these problems are NP-hard... A class of nonidentical parallel machine scheduling problems are considered in which the goal is to minimize the total weighted completion time. Models and relaxations are collected. Most of these problems are NP-hard, in the strong sense, or open problems, therefore approximation algorithms are studied. The review reveals that there exist some potential areas worthy of further research. 展开更多
关键词 parallel machine SCHEDULING REVIEW total weighted completion time RELAXATION algorithm
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高可扩展三维海洋可控源电磁高阶时域有限差分数值模拟
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作者 彭桦 吴志强 +5 位作者 肖调杰 李世杰 龚春叶 杨博 王浩东 陈星佑 《计算机工程与科学》 北大核心 2026年第3期422-433,共12页
海洋可控源电磁法MCSEM广泛应用于水下目标电磁探测、海洋电磁通信和海洋油气资源勘探等领域。然而,当前MCSEM数值模拟面临计算精度不足、并行通信效率低下和扩展性受限等问题,难以满足大规模三维复杂模型的计算需求。为此,设计并实现... 海洋可控源电磁法MCSEM广泛应用于水下目标电磁探测、海洋电磁通信和海洋油气资源勘探等领域。然而,当前MCSEM数值模拟面临计算精度不足、并行通信效率低下和扩展性受限等问题,难以满足大规模三维复杂模型的计算需求。为此,设计并实现了一种基于四阶时域有限差分的多层级并行数值模拟算法。该算法采用发射源间并行计算和子区域并行求解策略,充分挖掘了并行粒度,并通过远程内存访问技术有效降低通信开销,显著提升了并行效率。然后,通过多个典型案例测试验证了该算法的正确性与高效性。结果表明,在发射源数量为8个、区域规模为20 km×20 km×12 km且网格规模为245×245×512情况下,针对不考虑空气层的深海模型,采用8个进程组共2048个进程时,计算时间由串行的57.05 h缩短至72.96 s,加速比超线性达到2815.04,并行效率为137.45%;针对考虑空气层的浅海模型,采用8个进程组共256个进程时,计算时间由串行的64.78 h缩短至59.75 min,加速比为65.05,并行效率为25.41%,表明所提算法具有较好的可扩展性及计算精度,为海洋电磁数值模拟提供了一种高效的解决方案。 展开更多
关键词 海洋可控源电磁 高阶时域有限差分方法 高性能计算 远程内存访问 并行算法 单侧通信
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近场三维CZT波束形成算法的GPU实现及性能优化
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作者 徐浚洋 刘祖延 +2 位作者 于晓阳 周天 陈宝伟 《应用声学》 北大核心 2026年第2期434-443,共10页
针对在面阵波束形成过程中运算量大、难以做到实时成像的问题,文章使用图形处理器(GPU)在Visual Studio2019平台上对三维线性调频Z变换(CZT)波束形成算法进行加速,实现了三维CZT波束形成算法的并行化,从存储结构和对数据的访存等方面进... 针对在面阵波束形成过程中运算量大、难以做到实时成像的问题,文章使用图形处理器(GPU)在Visual Studio2019平台上对三维线性调频Z变换(CZT)波束形成算法进行加速,实现了三维CZT波束形成算法的并行化,从存储结构和对数据的访存等方面进行了针对性的设计,有效地利用了GPU的单指令多线程的特性,这些改进提升了算法的运行效率。通过实测数据显示,对于相同的声呐数据,GPU并行处理的计算效率高于CPU串行处理38倍以上,在采样点数量较少的情况下,三维CZT波束形成算法的计算效率明显优于传统的相移波束形成算法。这些发现证实了该方法在小型声呐设备中的应用前景广阔,具有一定的应用价值。 展开更多
关键词 CZT波束形成 图形处理器 平面阵列 并行计算 算法优化
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基于FPGA的高速并行时钟恢复算法设计
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作者 汤瑞新 刘文重 +2 位作者 张俊杰 李迎春 张倩武 《电子测量技术》 北大核心 2026年第2期18-25,共8页
在卫星高速数传系统中,发射端与接收端之间不可避免存在符号定时偏差且多普勒效应会进一步放大该偏差。时钟恢复算法是消除其影响的有效手段,然而现有的时钟恢复算法在并行实现时往往存在并行路数过高导致性能下降、实现复杂度较高等问... 在卫星高速数传系统中,发射端与接收端之间不可避免存在符号定时偏差且多普勒效应会进一步放大该偏差。时钟恢复算法是消除其影响的有效手段,然而现有的时钟恢复算法在并行实现时往往存在并行路数过高导致性能下降、实现复杂度较高等问题,难以在资源受限的系统中满足更高速率及更高定时偏差容忍度的需求。本文在传统前馈时钟恢复算法实现结构的基础上,提出了一种优化的并行实现结构:通过优化定时控制器、插值滤波器及符号抽取模块的架构,使其在两倍符号率采样条件下能够高效实现符号定时计算。同时改进LEE误差检测算法,提高定时误差估计精度和定时偏差容忍度。仿真与FPGA板级测试结果表明,该结构在QPSK调制格式下,能够容忍高达±1000×10^(-6)的定时频率偏差,并在长期测试中保持稳定的性能。此外,在2.5 GBaud符号率的实时接收机系统中,该并行结构相比传统并行时钟恢复环路结构节省约36%的LUT资源以及45%以上的Register和20%左右的DSP资源,展现出在资源受限高速实时通信系统中的显著应用价值。 展开更多
关键词 FPGA 并行时钟恢复算法 LEE
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基于PCNN-IGWO-SVM的电液伺服阀故障诊断算法研究
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作者 刘超 沈中豪 郑刚 《机床与液压》 北大核心 2026年第7期152-157,共6页
针对电液伺服阀故障诊断中存在特征提取不充分、故障识别精度低的问题,提出一种基于并行卷积神经网络(PCNN)与改进灰狼算法优化支持向量机(IGWO-SVM)的电液伺服阀故障诊断方法——PCNN-IGWO-SVM。采用融合门控循环单元的并行网络结构,... 针对电液伺服阀故障诊断中存在特征提取不充分、故障识别精度低的问题,提出一种基于并行卷积神经网络(PCNN)与改进灰狼算法优化支持向量机(IGWO-SVM)的电液伺服阀故障诊断方法——PCNN-IGWO-SVM。采用融合门控循环单元的并行网络结构,通过配置差异化卷积核实现多尺度时序特征提取;通过对GWO的初始种群生成策略和收敛因子衰减机制进行改进,构建基于改进灰狼算法优化支持向量机的分类模块,从而实现电液伺服阀的故障识别。最后,通过与PCNN、CNN-GWO-SVM模型进行对比实验,验证所提模型在电液伺服阀故障诊断任务中的性能。结果表明:所提模型的平均准确率达到98.62%,相较于PCNN(90.27%)、CNN-GWO-SVM(92.54%)故障诊断模型,具有更好的鲁棒性和特征提取能力,验证了所提算法具有更强的特征提取能力和更高的准确率;模型训练过程的损失值与准确率曲线均稳定收敛,t-SNE可视化显示经模型提取的特征具有清晰的聚类边界,混淆矩阵进一步验证了各故障类型的分类准确性。该方法为电液伺服阀的智能故障诊断提供了有效的技术方案。 展开更多
关键词 电液伺服阀 故障诊断 并行卷积神经网络 改进灰狼算法 支持向量机
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基于网格化粒子群搜索算法的最大浮点误差并行检测方法
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作者 冀立光 周蓓 +3 位作者 杨鸿儒 周玉畅 崔梦琦 许瑾晨 《计算机科学》 北大核心 2026年第2期124-132,共9页
浮点计算程序广泛应用于航空航天、人工智能、国防军事、金融结算等领域,浮点程序的计算精度和性能直接关系到相关应用的安全和效果。最大浮点误差值是衡量浮点计算程序精度的核心关键指标,浮点误差的累积效应也会导致难以承受的灾难,... 浮点计算程序广泛应用于航空航天、人工智能、国防军事、金融结算等领域,浮点程序的计算精度和性能直接关系到相关应用的安全和效果。最大浮点误差值是衡量浮点计算程序精度的核心关键指标,浮点误差的累积效应也会导致难以承受的灾难,因此需要研发一款精准高效的浮点数最大误差检测工具,为研究人员及时采取优化和干预措施提供支撑作用。对此,将浮点数最大误差检测问题转换为目标函数最大值搜索问题,充分发挥国产申威平台的主从架构两级并行计算模式的算力优势,深度挖掘粒子群启发式搜索算法的性能和精度潜能,采用“网格搜索、独立培养、分层汇聚、动态适应”的思想优化粒子群算法,根据搜索过程所处的不同阶段针对性地设置相关搜索参数,使得改进后的算法在搜索精度和搜索性能两个方面均有所提高。该算法为精确检测浮点数最大误差提供了一种新的实用工具和思路参考,同时进一步丰富了国产申威平台的工具库。 展开更多
关键词 浮点数 误差检测 粒子群优化算法 并行计算 申威平台
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基于混合增量计算的流式图并行处理
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作者 申玥 张婕 +3 位作者 张园 曹华伟 安学军 叶笑春 《计算机研究与发展》 北大核心 2026年第3期798-811,共14页
流式图能够对现实生活中数据快速变化的场景进行有效建模,在社交网络分析、内容推荐、异常检测等领域得到了广泛应用。基于流式图更新前后的2个图快照具有大量相同数据的事实,增量计算通过对历史计算结果进行存储和复用来降低迭代计算... 流式图能够对现实生活中数据快速变化的场景进行有效建模,在社交网络分析、内容推荐、异常检测等领域得到了广泛应用。基于流式图更新前后的2个图快照具有大量相同数据的事实,增量计算通过对历史计算结果进行存储和复用来降低迭代计算过程中的访存量和计算量,从而有效提升流式图处理的性能。然而,现有对图算法进行增量计算优化的研究往往受限于满足特定性质的图算法,而难以应用于通用图算法。针对通用图算法的增量计算优化问题,将增量计算进一步划分为基于修正和基于重计算的增量计算模式。理论上刨析了二者的异同点,实验上在不同图数据集、图算法和更新场景设置下测试了二者的性能差异。提出了混合增量计算模式,设计了确保切换正确性的算法,并通过随机森林分类器准确地预测切换时机。性能评估和切换效果分析表明通用图算法在混合增量计算模式下能够进行有效切换,并相比先进的流式图处理系统DZIG实现了平均1.25的加速比。 展开更多
关键词 流式图 增量计算 动态图处理 图算法 并行处理 图处理系统
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自适应规模邻近与K壳分解的空间并置核模式挖掘
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作者 陈雪瑶 芦俊丽 +1 位作者 段鹏 唐明香 《计算机应用研究》 北大核心 2026年第3期740-749,共10页
随着空间信息技术的发展和城市空间数据的快速增长,空间并置模式挖掘已成为理解空间对象潜在关联关系的重要手段。为克服传统方法在表达空间对象主导性及忽略实例规模差异方面的不足,提出一种面向城市功能分析的空间并置核模式挖掘方法... 随着空间信息技术的发展和城市空间数据的快速增长,空间并置模式挖掘已成为理解空间对象潜在关联关系的重要手段。为克服传统方法在表达空间对象主导性及忽略实例规模差异方面的不足,提出一种面向城市功能分析的空间并置核模式挖掘方法。该方法构建了基于实例面积的自适应规模邻近度公式,结合球邻域搜索策略,通过引入面积感知机制与动态阈值半径,有效提升邻近关系判定的准确性与效率。为识别具有核心作用的空间特征,引入K壳分解方法建立图结构,自动筛选出中心性强、结构稳定的核心特征。此外,通过基于特征对划分的并行挖掘策略,显著加快邻近关系计算和频繁模式生成过程。在真实城市POI数据集上的实验结果表明,该方法在模式质量上的整体参与度对比其他方法高出约10%,运行效率上平均提速约为33.8%。实验验证了该方法在模式质量与计算效率方面的显著优势,展现了良好的实际应用前景。 展开更多
关键词 空间并置核模式 自适应规模邻近 K壳分解 并行挖掘算法
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基于粒子群算法的大方捆打捆机控制系统
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作者 胡友耀 洪嘉伟 +3 位作者 冯翎瑜 娄立民 王琳 章明 《拖拉机与农用运输车》 2026年第3期87-93,共7页
目前的大型方形打捆机通过使用往复式柱塞向作物打捆面施加压力来实现打捆,针对此基于普通PID控制的大方捆打捆机控制系统存在的平稳控制响应较慢、自适应能力不好、抗干扰能力不强等问题,大多解决方法都是通过传统的PID控制、鲁棒控制... 目前的大型方形打捆机通过使用往复式柱塞向作物打捆面施加压力来实现打捆,针对此基于普通PID控制的大方捆打捆机控制系统存在的平稳控制响应较慢、自适应能力不好、抗干扰能力不强等问题,大多解决方法都是通过传统的PID控制、鲁棒控制等算法来实现,虽然能有效提高打捆控制系统的抗干扰能力,但由于打捆控制系统的模型相对简单,对打捆机打捆力的控制效果不明显。本文应用结合粒子群算法和并联级PID闭环反馈控制算法,建立了打捆柱塞的液压缸模型,并在设计基于目标打捆力的前馈控制,合并级联打捆液压压力的并联型PID闭环控制算法的基础上,利用粒子群优化算法的迭代寻优能力,实时计算确认前述并联型PID控制中的各项参数,通过基于不同的拖拉机驱动的PTO输出轴转速、打捆机整机的打捆柱塞负荷力的信号采集,控制系统通过查询MAP的算法计算出各参数的修正系数,实现在线实时调整PID的各参数,使对于打捆柱塞力的平稳控制中的参数时刻保持最优化,提升控制系统的自适应性。应用本优化算法的PID级联控制系统,在Simulink平台进行控制系统仿真分析。仿真分析了基于粒子群算法优化的PID控制下的阶跃相应曲线等。实验结果表明:比例因子K_(p)、K_(i)、K_(d)、K_(pfoward)的值分别为1.9068、2.8782、0.7279、2.0154时,系统稳定性达到最优,此时的系统适应度值为0.7987。相比于普通的PID控制与并联的PID控制,本文开发的粒子群算法优化后的级联PID控制算法的控制系统具有更优的控制精度和稳定性,能较好地提高整个控制系统的性能指标。本文开发系统匹配打捆机整机,田间实地测试,控制误差在4%以内,满足快速高效调整方形打捆机打捆力的要求。 展开更多
关键词 大方捆 嵌入式 粒子群算法 并联闭环控制
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一种改进型Canny的焊缝缺陷快速检测方法
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作者 穆向阳 王宣 《激光杂志》 北大核心 2026年第2期70-76,共7页
针对Canny算法在焊缝缺陷检测中出现边缘信息丢失、检测精度不足以及实时性偏低等问题,提出一种基于FPGA的改进型Canny焊缝缺陷检测方法。首先,该方法将自适应中值滤波和双边滤波技术结合起来,有效抑制噪声的同时最大限度地将焊缝边缘... 针对Canny算法在焊缝缺陷检测中出现边缘信息丢失、检测精度不足以及实时性偏低等问题,提出一种基于FPGA的改进型Canny焊缝缺陷检测方法。首先,该方法将自适应中值滤波和双边滤波技术结合起来,有效抑制噪声的同时最大限度地将焊缝边缘细节保留下来;其次,为了提升边缘提取的完整性,利用高斯加权的Sobel算子计算图像梯度;最后,通过引入基于梯度的自适应多级阈值选择策略,有效连接焊缝边缘的同时提升检测的自适应性。本研究采用FPGA的高速并行处理技术与分层流水线架构,开发了一种在硬件加速平台下的实时边缘检测系统。实验结果表明,该方法在焊缝区域内的边缘连通性较“自适应中值滤波+Canny算法”提升了24%,边缘强度提升了22.7%,并在100 MHz时钟频率下处理一张640×480的图片仅耗时4.1005 ms。本算法在检测精度及实时性方面更具优势,满足复杂环境下对焊缝缺陷检测的相关需求。 展开更多
关键词 CANNY算子 FPGA 自适应中值-双边滤波 自适应多级阈值 并行架构
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