期刊文献+
共找到65,972篇文章
< 1 2 250 >
每页显示 20 50 100
Accidental zero modes in a multiorbital superconductor with spin-orbital coupling
1
作者 XIANG Ke WANG Da WANG Qianghua 《物理学进展》 北大核心 2025年第5期250-259,共10页
The Majorana zero modes in vortex cores are of extensive interest in the context of topological quantum computing.However,a zero-energy bound state may arise accidentally but is not necessarily a Majorana zero mode.Su... The Majorana zero modes in vortex cores are of extensive interest in the context of topological quantum computing.However,a zero-energy bound state may arise accidentally but is not necessarily a Majorana zero mode.Such accidental zero modes should be carefully ruled out in experiment in order to identify the genuine Majorana zero modes.We show that in a spin-orbital coupled multi-band superconductor,such as the iron-selenide superconductor,accidental zero modes indeed arise in the vortex core if the pairing symmetry is the so-called nodeless d-wave(defined in the absence of spin-orbital coupling).Instead,if the pairing sym-metry is s_(++)or s_(+−)with respect to the Fermi pockets split by the spin-orbital coupling,the accidental zero modes do not appear in the limit of weak spin-orbital coupling.Our results are not only important in the experimental identification of Majorana zero modes,but also provide an avenue to pinpoint the pairing symmetry of the iron-selenide superconductor. 展开更多
关键词 spin-orbital coupling Andreev approximation accidental zero mode
在线阅读 下载PDF
Failure modes and transformation laws of reinforced concrete slabs under drop hammer impact
2
作者 Chunming Song Jiahe Zhong +3 位作者 Haotian Zhang Yuetang Zhao Zhongwei Zhang Feng Liu 《Defence Technology(防务技术)》 2025年第9期318-339,共22页
With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure m... With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure modes are transformed.In order to reveal the failure mode and transformation rule of reinforced concrete slabs under impact loads,a dynamic impact response test was carried out using a drop hammer test device.The dynamic data pertaining to the impact force,support reaction force,structural displacement,and reinforcement strain were obtained through the use of digital image correlation technology(DIC),impact force measurement,and strain measurement.The analysis of the ultimate damage state of the reinforced concrete slab identified four distinct types of impact failure modes:local failure by stamping,overall failure by stamping,local-overall coupling failure,and local failure by punching.Additionally,the influence laws of hammerhead shape,hammer height,and reinforcement ratio on the dynamic response and failure mode transformation of the slab were revealed.The results indicate that:(1)The local damage to the slab by the plane hammer is readily apparent,while the overall damage by the spherical hammer is more pronounced.(2)In comparison to the high reinforcement ratio slabs,the overall bending resistance of the low reinforcement ratio slabs is significantly inferior,and the slab back exhibits further cracks.(3)As the hammer height increases,the slab failure mode undergoes a transformation,shifting from local failure by stamping and overall failure by stamping to local-overall coupling failure and local failure by punching.(4)Three failure mode thresholds have been established,and by comparing the peak impact force with the failure thresholds,the failure mode of the slab can be effectively determined. 展开更多
关键词 Reinforced concrete slab Drop hammer impact test Dynamic response Crack propagation Failure mode
在线阅读 下载PDF
一种基于粗糙熵的改进K-modes聚类算法
3
作者 刘财辉 曾雄 谢德华 《南京理工大学学报》 CAS CSCD 北大核心 2024年第3期335-341,共7页
K-modes聚类算法被广泛应用于人工智能、数据挖掘等领域。传统的K-modes聚类算法有不错的聚类效果,但是存在迭代次数多、计算量大、容易受到冗余属性的干扰等问题,且仅采用简单的0-1匹配的方法来定义2个样本属性值之间的距离,没有充分... K-modes聚类算法被广泛应用于人工智能、数据挖掘等领域。传统的K-modes聚类算法有不错的聚类效果,但是存在迭代次数多、计算量大、容易受到冗余属性的干扰等问题,且仅采用简单的0-1匹配的方法来定义2个样本属性值之间的距离,没有充分考虑每个属性对聚类结果的影响。针对上述问题,该文将粗糙熵引入K-modes算法。首先利用粗糙集属性约简算法消除冗余属性,确定各属性的重要程度;然后利用粗糙熵确定每个属性的权重,从而定义新的类内距离。将该文所提算法与传统的K-modes聚类算法分别在4组公开数据集上进行对比试验。试验结果表明,该文所提算法聚类准确率比传统的K-modes聚类算法更高。 展开更多
关键词 聚类 K-modes算法 粗糙集 粗糙熵 属性约简 权重
在线阅读 下载PDF
K-Modes聚类数据收集和发布过程中的混洗差分隐私保护方法 被引量:6
4
作者 蒋伟进 陈艺琳 +3 位作者 韩裕清 吴玉庭 周为 王海娟 《通信学报》 EI CSCD 北大核心 2024年第1期201-213,共13页
针对目前聚类数据收集与发布安全性不足的问题,为保护聚类数据中的用户隐私并提高数据质量,基于混洗差分隐私模型,提出一种去可信第三方的K-Modes聚类数据收集和发布的隐私保护方法。首先,使用K-Modes聚类数据收集算法对用户数据进行采... 针对目前聚类数据收集与发布安全性不足的问题,为保护聚类数据中的用户隐私并提高数据质量,基于混洗差分隐私模型,提出一种去可信第三方的K-Modes聚类数据收集和发布的隐私保护方法。首先,使用K-Modes聚类数据收集算法对用户数据进行采样并加噪,再通过填补取值域随机排列发布算法打乱采样数据的初始顺序,使恶意攻击者不能根据用户与数据之间的关系识别出目标用户。然后,尽可能减小噪声的干扰,利用循环迭代的方式计算出新的质心完成聚类。最后,从理论层面上分析了以上3种方法的隐私性、可行性和复杂度,并利用3个真实数据集和近年来具有权威性的同类算法KM、DPLM、LDPKM等进行准确率、熵值的对比,验证所提方法的有效性。实验结果表明,所提方法的隐私保护和发布数据质量均优于当前同类算法。 展开更多
关键词 混洗差分隐私 K-modes聚类 隐私保护 数据收集 数据发布
在线阅读 下载PDF
A near-infrared all-fiber mode monitor based on the mini-two-path Mach-Zehnder interferometer
5
作者 ZHU Xiao-Jun LIU Yu +5 位作者 WU Yue ZHUANG Hao-Ran SUN Dan SHI Yue-Chun CAO Juan YANG Yong-Jie 《红外与毫米波学报》 北大核心 2025年第3期352-357,共6页
A novel near-infrared all-fiber mode monitor based on a mini-two-path Mach-Zehnder interferometer(MTP-MZI)is proposed.The MTP-MZI mode monitor is created by fusing a section of(no-core fiber,NCF)and a(single-mode fibe... A novel near-infrared all-fiber mode monitor based on a mini-two-path Mach-Zehnder interferometer(MTP-MZI)is proposed.The MTP-MZI mode monitor is created by fusing a section of(no-core fiber,NCF)and a(single-mode fiber,SMF)together with an optical fiber fusion splicer,establishing two distinct centimeter-level optical transmission paths.Since the high-order modes in NCF transmit near-infrared light more sensitively to curvature-induced energy leakage than the fundamental mode in SMF,the near-infrared high-order mode light leaks out of NCF when the curvature changes,causing the MTP-MZI transmission spectrum to change.By ana⁃lyzing the relationship between the curvature,transmission spectrum,and spatial frequency spectrum,the modes involved in the interference can be studied,thereby revealing the mode transmission characteristics of near-infra⁃red light in optical fibers.In the verification experiments,higher-order modes were excited by inserting a novel hollow-core fiber(HCF)into the MTP-MZI.When the curvature of the MTP-MZI changes,the near-infrared light high-order mode introduced into the device leaks out,causing the transmission spectrum to return to its origi⁃nal state before bending and before the HCF was spliced.The experimental results demonstrate that the MTP-MZI mode monitor can monitor the fiber modes introduced from the external environment,providing both theoretical and experimental foundations for near-infrared all-fiber mode monitoring in optical information systems. 展开更多
关键词 near-infrared mode monitor Mach-Zehnder interferometer two-path structure all-fiber-format
在线阅读 下载PDF
Investigation on the Ice Load on a Cylinder Vertically Breaking through Model Ice Sheet from Underneath
6
作者 ZHAO Wei−hang TIAN Yu−kui +3 位作者 JI Shao−peng GANG Xu−hao YU Chao−ge KONG Shuai 《船舶力学》 北大核心 2025年第6期964-975,共12页
Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical e... Ice load on underwater vehicles breaking through ice covers from underneath is a significant concern for researchers in polar exploration,and the research on this problem is still in its early stages.Both mechanical experimental measurement and numerical simulation pose research challenges.This study focuses on the ice load of a cylinder structure breaking upward through the ice sheet form underneath in the Small Ice Model Basin of China Ship Scientific Research Center(CSSRC SIMB).A high-speed camera system was employed to observe the ice sheet failure during the tests,in which,with the loading position as center,local radial cracks and circumferential cracks were generated.A load sensor was used to measure the overall ice load during this process.Meanwhile,a numerical model was developed using LS-DYNA for validation and comparison.With this model,numerical simulation was conducted under various ice thicknesses and upgoing speeds to analyze the instantaneous curves of ice load.The calculation results were statistically analyzed under different working conditions to determine the influence of the factors on the ice load of the cylinder.The study explores the measurement method about ice load of objects vertically breaking through model ice sheet and is expected to provide some fundamental insights into the safety design of underwater structures operating in ice waters. 展开更多
关键词 CYLINDER model test failure mode crack propagation ice load numerical modeling
在线阅读 下载PDF
Fault-tolerant control for diesel engine air path system via sliding mode surface
7
作者 WU Wen-jie ZHANG Yi-xin +4 位作者 WANG Xing-jian WANG Shao-ping ZHANG Jian ZHENG Wei TAO Mo 《控制理论与应用》 北大核心 2025年第8期1570-1577,共8页
The operating environment of the diesel engine air path system is complex and may be affected by external random disturbances.Potentially leading to faults.This paper addresses the fault-tolerant control problem of th... The operating environment of the diesel engine air path system is complex and may be affected by external random disturbances.Potentially leading to faults.This paper addresses the fault-tolerant control problem of the diesel engine air path system,assuming that the system may simultaneously be affected by actuator faults and external random disturbances,a disturbance observer-based sliding mode controller is designed.Through the linear matrix inequality technique for solving observer and controller gains,optimal gain matrices can be obtained,eliminating the manual adjustment process of controller parameters and reducing the chattering phenomenon of the sliding mode surface.Finally,the effectiveness of the proposed method is verified through simulation analysis. 展开更多
关键词 disel engine air path fault-tolerant control sliding mode control disturbance observer
在线阅读 下载PDF
Modeling and sliding mode control based on inverse compensation of piezo-positioning system
8
作者 LI Zhi-bin XIN Yuan-ze +1 位作者 ZHANG Jian-qiang SUN Chong-shang 《中国光学(中英文)》 北大核心 2025年第1期170-185,共16页
In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis... In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis nonlinear characteristics of piezo-positioning actuator.The static nonlinear part and dynamic linear part of the Hammerstein model are represented by models obtained through the Prandtl-Ishlinskii(PI)model and Hankel matrix system identification method,respectively.This model demonstrates good generalization capability for typical input frequencies below 200 Hz.A sliding mode inverse compensation tracking control strategy based on P-I inverse model and integral augmentation is proposed.Experimental results show that compared with PID inverse compensation control and sliding mode control without inverse compensation,the sliding mode inverse compensation control has a more ideal step response and no overshoot,moreover,the settling time is only 6.2 ms.In the frequency domain,the system closed-loop tracking bandwidth reaches 119.9 Hz,and the disturbance rejection bandwidth reaches 86.2 Hz.The proposed control strategy can effectively compensate the hysteresis nonlinearity,and improve the tracking accuracy and antidisturbance capability of piezo-positioning system. 展开更多
关键词 piezo-positioning system hysteresis nonlinearity Hammerstein model Prandtl-Ishlinskii(P-I)model system identification sliding mode control
在线阅读 下载PDF
Design and implementation of disturbance sliding mode observer for enhancing the dynamic control precision of inertial stabilization platform
9
作者 ZHANG Zhidong YANG Gongliu +2 位作者 CAI Qingzhong FAN Jing LI Tao 《Journal of Systems Engineering and Electronics》 2025年第3期791-802,共12页
In order to enhance the dynamic control precision of inertial stabilization platform(ISP),a disturbance sliding mode observer(DSMO)is proposed in this paper suppressing disturbance torques inherent within the system.T... In order to enhance the dynamic control precision of inertial stabilization platform(ISP),a disturbance sliding mode observer(DSMO)is proposed in this paper suppressing disturbance torques inherent within the system.The control accuracy of ISP is fundamentally circumscribed by various disturbance torques in rotating shaft.Therefore,a dynamic model of ISP incorporating composite perturbations is established with regard to the stabilization of axis in the inertial reference frame.Subsequently,an online estimator for control loop uncertainties based on the sliding mode control algorithm is designed to estimate the aggregate disturbances of various parameters uncertainties and other unmodeled disturbances that cannot be accurately calibrated.Finally,the proposed DSMO is integrated into a classical proportional-integral-derivative(PID)control scheme,utilizing feedforward approach to compensate the composite disturbance in the control loop online.The effectiveness of the proposed disturbance observer is validated through simulation and hardware experimentation,demonstrating a significant improvement in the dynamic control performance and robustness of the classical PID controller extensively utilized in the field of engineering. 展开更多
关键词 inertial stabilization platform disturbance suppression sliding mode observer robust control
在线阅读 下载PDF
Cross-platform mission planning for UAVs under carrier delivery mode
10
作者 Junhong Jin Genlai Zhang +6 位作者 Xin Li Xichao Su Chen Lu Yujie Cheng Yu Ding Lei Wang Xinwei Wang 《Defence Technology(防务技术)》 2025年第11期76-97,共22页
As battlefield scale enlarges,cross-platform collaborative combat provides an appealing paradigm for modern warfare.Complicated constraints and vast solution space pose great challenge for reasonable and efficient mis... As battlefield scale enlarges,cross-platform collaborative combat provides an appealing paradigm for modern warfare.Complicated constraints and vast solution space pose great challenge for reasonable and efficient mission planning,where path planning and target assignment are tightly coupled.In this paper,we focus on UAV mission planning under carrier delivery mode(e.g.,by aircraft carrier,ground vehicle,or transport aircraft) and design a three-layer hierarchical solution framework.In the first layer,we simultaneously determine delivery points and target set division by clustering.To address the safety concerns of radar risk and UAV endurance,an improved density peak clustering algorithm is developed by constraint fusio n.In the second layer,mission planning within each cluster is viewed as a coope rative multiple-task assignment problem.A hybrid heuristic algorithm that integrates a voting-based heuristic solution generation strategy(VHSG) and a stochastic variable neighborhood search(SVNS),called VHSG-SVNS,is proposed for rapid solution.Based on the results of the first two layers,the third layer transforms carrier path planning into a multiple-vehicle routing problem with time window.The cost between any two nodes is calculated by the A~* algorithm,and the genetic algorithm is then implemented to determine the global route.Finally,a practical mission scenario containing 200 targets is used to validate the effectiveness of the designed framework,where three layers cooperate well with each other to generate satisfactory combat scheduling.Comparisons are made in each layer to highlight optimum-seeking capability and efficiency of the proposed algorithms.Works done in this paper provide a simple but efficient solution framework for cross-platform cooperative mission planning problems,and can be potentially extended to other applications such as post-disaster search and rescue,forest surveillance and firefighting,logistics pick and delivery,etc. 展开更多
关键词 Cross-platform mission planning UAV Carrier delivery mode Clustering algorithm Heuristic optimization algorithm
在线阅读 下载PDF
Non-singular fast terminal sliding mode control for roll-pitch seeker based on extended state observers
11
作者 XIAO Bowen XIA Qunli 《Journal of Systems Engineering and Electronics》 2025年第2期537-551,共15页
For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode contr... For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode control method, aimed at resolving the frame control problem of roll-pitch seeker tracking high maneu-vering target. The sliding mode surface is structured around the principle of segmentation, which enables the control system’s rapid attainment of the zero point and ensure global fast conver-gence. The system’s state is more swiftly converged to the slid-ing mode surface through an improved adaptive fast dual power reaching law. Utilizing an extended state observer, the overall disturbance is both identified and compensated. The validation of the system’s stability and its convergence within a finite-time is grounded in Lyapunov’s stability criteria. The performance of the introduced control method is confirmed through roll-pitch seeker tracking control simulation. Data analysis reveals that newly proposed control technique significantly outperforms existing sliding mode control methods by rapidly converging the frame to the target angle, reduce the tracking error of the detec-tor for the target, and bolster tracking precision of the roll-pitch seeker huring disturbed conditions. 展开更多
关键词 air-to-air missile roll-pitch seeker finite-time con-vergence combined sliding mode control extended state observer
在线阅读 下载PDF
A diagnosis method based on graph neural networks embedded with multirelationships of intrinsic mode functions for multiple mechanical faults
12
作者 Bin Wang Manyi Wang +3 位作者 Yadong Xu Liangkuan Wang Shiyu Chen Xuanshi Chen 《Defence Technology(防务技术)》 2025年第8期364-373,共10页
Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types o... Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types of signals or faults in individual mechanical components while being constrained by data types and inherent characteristics.To address the limitations of existing methods,we propose a fault diagnosis method based on graph neural networks(GNNs)embedded with multirelationships of intrinsic mode functions(MIMF).The approach introduces a novel graph topological structure constructed from the features of intrinsic mode functions(IMFs)of monitored signals and their multirelationships.Additionally,a graph-level based fault diagnosis network model is designed to enhance feature learning capabilities for graph samples and enable flexible application across diverse signal sources and devices.Experimental validation with datasets including independent vibration signals for gear fault detection,mixed vibration signals for concurrent gear and bearing faults,and pressure signals for hydraulic cylinder leakage characterization demonstrates the model's adaptability and superior diagnostic accuracy across various types of signals and mechanical systems. 展开更多
关键词 Fault diagnosis Graph neural networks Graph topological structure Intrinsic mode functions Feature learning
在线阅读 下载PDF
Modeling and analysis of maneuver laws based on higher order multi-resolution dynamic mode decomposition for hypersonic glide vehicles
13
作者 Zichu Liu Yudong Hu +2 位作者 Changsheng Gao Wuxing Jing Xudong Ji 《Defence Technology(防务技术)》 2025年第6期34-47,共14页
The precise characterization of hypersonic glide vehicle(HGV) maneuver laws in complex flight scenarios still faces challenges. Non-stationary changes in flight state due to abrupt changes in maneuver modes place high... The precise characterization of hypersonic glide vehicle(HGV) maneuver laws in complex flight scenarios still faces challenges. Non-stationary changes in flight state due to abrupt changes in maneuver modes place high demands on the accuracy of modeling methods. To address this issue, a novel maneuver laws modeling and analysis method based on higher order multi-resolution dynamic mode decomposition(HMDMD) is proposed in this work. A joint time-space-frequency decomposition of the vehicle's state sequence in the complex flight scenario is achieved with the higher order Koopman assumption and standard multi-resolution dynamic mode decomposition, and an approximate dynamic model is established. The maneuver laws can be reconstructed and analyzed with extracted multi-scale spatiotemporal modes with clear physical meaning. Based on the dynamic model of HGV, two flight scenarios are established with constant angle of attack and complex maneuver laws, respectively. Simulation results demonstrate that the maneuver laws obtained using the HMDMD method are highly consistent with those derived from the real dynamic model, the modeling accuracy is better than other common modeling methods, and the method has strong interpretability. 展开更多
关键词 Hypersonic glide vehicle Dynamic mode decomposition Higher order koopman assumption Manoeuvre law modeling INTERPRETABILITY
在线阅读 下载PDF
基于批次拆分机制的IMODE算法求解成品卷烟生产调度问题
14
作者 安裕强 张源 +1 位作者 邹平 陶翼飞 《中国机械工程》 北大核心 2025年第8期1893-1903,共11页
针对成品卷烟生产调度问题,结合卷烟企业生产实际,以承担成品卷烟生产任务的卷包车间为研究对象,将其转换为异构并行机分批调度问题,以卷包机组的总切换次数和同停综合评价时间为目标建立符合成品卷烟生产工况的仿真优化模型,并设计一... 针对成品卷烟生产调度问题,结合卷烟企业生产实际,以承担成品卷烟生产任务的卷包车间为研究对象,将其转换为异构并行机分批调度问题,以卷包机组的总切换次数和同停综合评价时间为目标建立符合成品卷烟生产工况的仿真优化模型,并设计一种基于批次拆分机制的改进多目标差分进化(IMODE)算法进行求解。为满足分批生产特点,该算法采用一种不规则的矩阵编码方式表示可行解,基于反向批次学习策略生成初始种群,通过矩阵向量间的差分运算更新种群个体,采用批次拆分机制详细划分批次批量,并对子代个体进行邻域搜索,在选择操作中引入改进精英保留策略,以提高算法的寻优能力。最后基于不同订单量和车间规模的卷烟企业生产实例进行实验对比,验证了IMODE算法的性能及其在解决成品卷烟生产调度问题上的有效性。 展开更多
关键词 异构并行机 批次拆分 总切换次数 同停综合评价时间 多目标差分进化算法
在线阅读 下载PDF
基于新的相异度量的模糊K-Modes聚类算法 被引量:5
15
作者 白亮 曹付元 梁吉业 《计算机工程》 CAS CSCD 北大核心 2009年第16期192-194,共3页
传统的模糊K-Modes聚类算法采用简单匹配方法度量对象与Mode之间的相异程度,没有充分考虑Mode对类的代表程度,容易造成信息的丢失,弱化了类内的相似性。针对上述问题,通过对象对类的隶属度反映Mode对类的代表程度,提出一种新的相异度量... 传统的模糊K-Modes聚类算法采用简单匹配方法度量对象与Mode之间的相异程度,没有充分考虑Mode对类的代表程度,容易造成信息的丢失,弱化了类内的相似性。针对上述问题,通过对象对类的隶属度反映Mode对类的代表程度,提出一种新的相异度量,并将它应用于传统的模糊K-Modes聚类算法。与传统的K-Modes和模糊K-Modes聚类算法相比,该相异度量是有效的。 展开更多
关键词 模糊K—modes聚类算法 相异度量 类中心
在线阅读 下载PDF
基于贝叶斯距离的K-modes聚类算法 被引量:5
16
作者 赵亮 刘建辉 张昭昭 《计算机工程与科学》 CSCD 北大核心 2017年第1期188-193,共6页
K-modes算法中原有的分类变量间距离度量方法无法体现属性值之间差异,对此提出了一种基于朴素贝叶斯分类器中间运算结果的距离度量。该度量构建代表分类变量的特征向量并计算向量间的欧氏距离作为变量间的距离。将提出的距离度量代入K-m... K-modes算法中原有的分类变量间距离度量方法无法体现属性值之间差异,对此提出了一种基于朴素贝叶斯分类器中间运算结果的距离度量。该度量构建代表分类变量的特征向量并计算向量间的欧氏距离作为变量间的距离。将提出的距离度量代入K-modes聚类算法并在多个UCI公共数据集上与其他度量方法进行比较,实验结果表明该距离度量更加有效。 展开更多
关键词 K—modes聚类算法 分类变量 朴素贝叶斯分类器 距离度量
在线阅读 下载PDF
动态的模糊K-Modes初始化算法 被引量:1
17
作者 张伟 周霆 +1 位作者 陈芸 邹汉斌 《计算机工程与设计》 CSCD 北大核心 2006年第4期682-683,707,共3页
模糊K-Modes聚类算法针对分类属性的数据进行聚类,使用爬山法来寻找最优解,因此该算法对初始值较为敏感。为了克服该缺点,提出一种动态的模糊K-Modes初始化算法,该方法能够自动确定聚类数目,以及对应的聚类中心;而且能够应用于数值属性... 模糊K-Modes聚类算法针对分类属性的数据进行聚类,使用爬山法来寻找最优解,因此该算法对初始值较为敏感。为了克服该缺点,提出一种动态的模糊K-Modes初始化算法,该方法能够自动确定聚类数目,以及对应的聚类中心;而且能够应用于数值属性和分类属性相混合的数据集。该初始化算法可以有效地克服模糊K-Modes算法对初值的敏感性。实验的结果表明了该初始化算法的可行性和有效性。 展开更多
关键词 模糊 K—modes算法 动态初始化算法 聚类中心 分类属性
在线阅读 下载PDF
基于互信息量的改进K-Modes聚类方法 被引量:3
18
作者 吴润秀 《统计与决策》 CSSCI 北大核心 2012年第6期89-91,共3页
文章提出了一种基于互信息量的改进K-Modes聚类方法,采用样本互信息来刻画数据对象属性之间的相互关系。在此基础上提出了一种新的距离度量,该距离度量方法既考虑了对象某个属性值本身的不同,又考虑了对象其它属性对该属性值的影响,使... 文章提出了一种基于互信息量的改进K-Modes聚类方法,采用样本互信息来刻画数据对象属性之间的相互关系。在此基础上提出了一种新的距离度量,该距离度量方法既考虑了对象某个属性值本身的不同,又考虑了对象其它属性对该属性值的影响,使之更符合实际问题情况。实验结果表明,聚类方法有效地提高了聚类精度。 展开更多
关键词 互信息量 K—modes 聚类方法
在线阅读 下载PDF
模糊K-Modes聚类精确度分析 被引量:14
19
作者 赵恒 杨万海 《计算机工程》 CAS CSCD 北大核心 2003年第12期27-28,175,共3页
模糊K-Modes聚类算法是对具有分类属性的数据进行聚类的一种有效的算法。为了评价聚类结果,以具有明确分类结构的数据作为输入数据,将模糊K-Modes聚类结果与原始数据的分类结构进行对比,分析了确定它们之间对应关系的方法,在期望聚... 模糊K-Modes聚类算法是对具有分类属性的数据进行聚类的一种有效的算法。为了评价聚类结果,以具有明确分类结构的数据作为输入数据,将模糊K-Modes聚类结果与原始数据的分类结构进行对比,分析了确定它们之间对应关系的方法,在期望聚类结果应该具有的特点的基础上,对现有的精确度定义和计算方法进行修正,在划分相似度的基础上,重新定义模糊K-Modes聚类精确度。 展开更多
关键词 模糊K-modes聚类 精确度 分类属性 相似度
在线阅读 下载PDF
Close-space modes in shock dynamic analysis 被引量:4
20
作者 贺少华 吴新跃 +1 位作者 万强 谢最伟 《海军工程大学学报》 CAS 北大核心 2011年第5期31-35,共5页
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部