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S-box:six-dimensional compound hyperchaotic map and artificial bee colony algorithm 被引量:1
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作者 Ye Tian Zhimao Lu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期232-241,共10页
Being as unique nonlinear components of block ciphers,substitution boxes(S-boxes) directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes th... Being as unique nonlinear components of block ciphers,substitution boxes(S-boxes) directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes that simultaneously meet with multiple cryptographic criteria such as bijection,non-linearity,strict avalanche criterion(SAC),bits independence criterion(BIC),differential probability(DP) and linear probability(LP).To deal with this problem,a chaotic S-box based on the artificial bee colony algorithm(CSABC) is designed.It uses the S-boxes generated by the six-dimensional compound hyperchaotic map as the initial individuals and employs ABC to improve their performance.In addition,it considers the nonlinearity and differential uniformity as the fitness functions.A series of experiments have been conducted to compare multiple cryptographic criteria of this algorithm with other algorithms.Simulation results show that the new algorithm has cryptographically strong S-box while meeting multiple cryptographic criteria. 展开更多
关键词 substitution boxes(S-boxes) multiple cryptographic criteria six-dimensional compound hyperchaotic map artificial bee colony algorithm(ABC).
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A novel compound biped locomotion algorithm for humanoid robots to realize biped walking
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作者 Ruiwu XIN Nanfeng XIAO 《控制理论与应用(英文版)》 EI 2009年第1期23-28,共6页
In this paper, a compound biped locomotion algorithm for a humanoid robot under development is presented. This paper is organized in two main parts. In the first part, it mainly focuses on the structural design for th... In this paper, a compound biped locomotion algorithm for a humanoid robot under development is presented. This paper is organized in two main parts. In the first part, it mainly focuses on the structural design for the humanoid. In the second part, the compound biped locomotion algorithm is presented based on the reference motion and reference Zero Moment Point (ZMP). This novel algorithm includes calculation of the upper body motion and trajectory of the Center of Gravity (COG) of the robot. First, disturbances from the environment are eliminated by the compensational movement of the upper body; then based on the error between a reference ZMP and the real ZMP as well as the relation between ZMP and CoG, the CoG error is calculated, thus leading to the CoG trajectory. Then, the motion of the robot converges to its reference motion, generating stable biped walking. Because the calculation of upper body motion and trajectory of CoG both depend on the reference motion, they can work in parallel, thus providing double insurances against the robot's collapse. Finally, the algorithm is validated by different kinds of simulation experiments. 展开更多
关键词 Humanoid robot Structural design compound biped locomotion algorithm Simulation experiments
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基于Matlab的直流电机CMAC-PID智能控制系统设计 被引量:5
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作者 闻霞 吴龙 +1 位作者 李青虹 任雯 《三明学院学报》 2009年第2期165-167,共3页
为克服常规PID算法不能实时调整参数、非线性逼近能力差的问题,提出了直流电机的小脑模型神经网络(CMAC)与PID复合控制的策略。运用Matlab软件设计了CMAC-PID自适应智能控制器,证明了该算法的可行性、有效性,并得到了较为理想的控制效果。
关键词 直流电机 CMAC-PD复合控制算法 MATLAB仿真
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基于遗传禁忌搜索算法优化的CMAC-PID液压弯辊复合控制
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作者 郎宪明 屈宝存 张奎 《燕山大学学报》 CAS 2009年第5期455-458,共4页
针对液压伺服系统存在时滞、饱和等非线性特点,提出一种基于遗传禁忌搜索算法的CMAC-PID复合控制的板形控制策略,用遗传禁忌搜索算法优化PID控制器的初始参数,然后结合CMAC网络有效控制板形控制系统中弯辊力。仿真证明,该复合控制算法... 针对液压伺服系统存在时滞、饱和等非线性特点,提出一种基于遗传禁忌搜索算法的CMAC-PID复合控制的板形控制策略,用遗传禁忌搜索算法优化PID控制器的初始参数,然后结合CMAC网络有效控制板形控制系统中弯辊力。仿真证明,该复合控制算法提高了系统的精度,加快了系统的响应速度,并且具备较强的抗干扰能力。 展开更多
关键词 遗传禁忌搜索算法 CMAC神经网络 PID控制 板形控制 复合控制
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Bionic Mosaic Method of Panoramic Image Based on Compound Eye of Fly 被引量:8
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作者 Haipeng Chen Xuanjing Shen +1 位作者 Xiaofei Li Yushan Jin 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第4期440-448,共9页
To satisfy the requirements of real-time and high quality mosaics, a bionic compound eye visual system was designed by simulating the visual mechanism of a fly compound eye. Several CCD cameras were used in this syste... To satisfy the requirements of real-time and high quality mosaics, a bionic compound eye visual system was designed by simulating the visual mechanism of a fly compound eye. Several CCD cameras were used in this system to imitate the small eyes of a compound eye. Based on the optical analysis of this system, a direct panoramic image mosaic algorithm was proposed. Several sub-images were collected by the bionic compound eye visual system, and then the system obtained the overlapping proportions of these sub-images and cut the overlap sections of the neighboring images. Thus, a panoramic image with a large field of view was directly mosaicked, which expanded the field and guaranteed the high resolution. The experimental results show that the time consumed by the direct mosaic algorithm is only 2.2% of that by the traditional image mosaic algorithm while guaranteeing mosaic quality. Furthermore, the proposed method effectively solved the problem of misalignment of the mosaic image and eliminated mosaic cracks as a result of the illumination factor and other factors. This method has better real-time properties compared to other methods. 展开更多
关键词 bionic compound eye panoramic image image mosaic direct mosaic algorithm
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Efficient thermal analysis method for large scale compound semiconductor integrated circuits based on heterojunction bipolar transistor 被引量:1
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作者 Shi-Zheng Yang Hong-Liang Lv +3 位作者 Yu-Ming Zhang Yi-Men Zhang Bin Lu Si-Lu Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期598-606,共9页
In this paper, an efficient thermal analysis method is presented for large scale compound semiconductor integrated circuits based on a heterojunction bipolar transistor with considering the change of thermal conductiv... In this paper, an efficient thermal analysis method is presented for large scale compound semiconductor integrated circuits based on a heterojunction bipolar transistor with considering the change of thermal conductivity with temperature.The influence caused by the thermal conductivity can be equivalent to the increment of the local temperature surrounding the individual device. The junction temperature for each device can be efficiently calculated by the combination of the semianalytic temperature distribution function and the iteration of local temperature with high accuracy, providing a temperature distribution for a full chip. Applying this method to the InP frequency divider chip and the GaAs analog to digital converter chip, the computational results well agree with the results from the simulator COMSOL and the infrared thermal imager respectively. The proposed method can also be applied to thermal analysis in various kinds of semiconductor integrated circuits. 展开更多
关键词 thermal analysis temperature distribution iterative algorithm compound semiconductor inte-grated circuit
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Simulation and experimental research of digital valve control servo system based on CMAC-PID control method 被引量:6
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作者 赵劲松 Zhao Zining +2 位作者 Wang Zhipeng Zhang Chuanbi Yao Jing 《High Technology Letters》 EI CAS 2017年第3期306-314,共9页
Digital valve control servo system is studied in this paper. In order to solve the system problems of poor control precision and slow response time,a CMAC-PID( cerebellar model articulation controller-PID) compound co... Digital valve control servo system is studied in this paper. In order to solve the system problems of poor control precision and slow response time,a CMAC-PID( cerebellar model articulation controller-PID) compound control method is proposed. This compound controller consists of two components: one is a traditional PID for the feedback control to guarantee stability of the system; the other is the CMAC control algorithm to form a feed-forward control for achieving high control precision and short response time of the controlled plant. Then the CMAC-PID compound control method is used in the digital valve control servo system to improve its control performance. Through simulation and experiment,the proposed CMAC-PID compound control method is superior to the traditional PID control for enhancing stability and robustness,and thus this compound control can be used as a new control strategy for the digital valve control servo system. 展开更多
关键词 electro-servo system digital hydraulic digital valve cmac-pid compound control rapid control prototyping technology
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Brittle and ductile characteristics of intermetallic compounds in magnesium alloys: A large-scale screening guided by machine learning 被引量:1
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作者 Russlan Jaafreh Yoo Seong Kang Kotiba Hamad 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第1期392-404,共13页
In the present work,we have employed machine learning(ML)techniques to evaluate ductile-brittle(DB)behaviors in intermetallic compounds(IMCs)which can form magnesium(Mg)alloys.This procedure was mainly conducted by a ... In the present work,we have employed machine learning(ML)techniques to evaluate ductile-brittle(DB)behaviors in intermetallic compounds(IMCs)which can form magnesium(Mg)alloys.This procedure was mainly conducted by a proxy-based method,where the ratio of shear(G)/bulk(B)moduli was used as a proxy to identify whether the compound is ductile or brittle.Starting from compounds information(composition and crystal structure)and their moduli,as found in open databases(AFLOW),ML-based models were built,and those models were used to predict the moduli in other compounds,and accordingly,to foresee the ductile-brittle behaviors of these new compounds.The results reached in the present work showed that the built models can effectively catch the elastic moduli of new compounds.This was confirmed through moduli calculations done by density functional theory(DFT)on some compounds,where the DFT calculations were consistent with the ML prediction.A further confirmation on the reliability of the built ML models was considered through relating between the DB behavior in MgBe_(13) and MgPd_(2),as evaluated by the ML-predicted moduli,and the nature of chemical bonding in these two compounds,which in turn,was investigated by the charge density distribution(CDD)and electron localization function(ELF)obtained by DFT methodology.The ML-evaluated DB behaviors of the two compounds was also consistent with the DFT calculations of CDD and ELF.These findings and confirmations gave legitimacy to the built model to be employed in further prediction processes.Indeed,as examples,the DB characteristics were investigated in IMCs that might from in three Mg alloy series,involving AZ,ZX and WE. 展开更多
关键词 Mg alloys Intermetallic compounds Ductile-brittle Machine learning algorithm Features DFT
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An Improved Honey Badger Algorithm through Fusing Multi-Strategies 被引量:1
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作者 Zhiwei Ye Tao Zhao +2 位作者 Chun Liu Daode Zhang Wanfang Bai 《Computers, Materials & Continua》 SCIE EI 2023年第8期1479-1495,共17页
TheHoney Badger Algorithm(HBA)is a novelmeta-heuristic algorithm proposed recently inspired by the foraging behavior of honey badgers.The dynamic search behavior of honey badgers with sniffing and wandering is divided... TheHoney Badger Algorithm(HBA)is a novelmeta-heuristic algorithm proposed recently inspired by the foraging behavior of honey badgers.The dynamic search behavior of honey badgers with sniffing and wandering is divided into exploration and exploitation in HBA,which has been applied in photovoltaic systems and optimization problems effectively.However,HBA tends to suffer from the local optimum and low convergence.To alleviate these challenges,an improved HBA(IHBA)through fusing multi-strategies is presented in the paper.It introduces Tent chaotic mapping and composite mutation factors to HBA,meanwhile,the random control parameter is improved,moreover,a diversified updating strategy of position is put forward to enhance the advantage between exploration and exploitation.IHBA is compared with 7 meta-heuristic algorithms in 10 benchmark functions and 5 engineering problems.The Wilcoxon Rank-sum Test,Friedman Test and Mann-WhitneyU Test are conducted after emulation.The results indicate the competitiveness and merits of the IHBA,which has better solution quality and convergence traits.The source code is currently available from:https://github.com/zhaotao789/IHBA. 展开更多
关键词 Honey Badger algorithm multi-strategies fusion tent chaotic mapping compound random factors
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Quantitative Structure-retention Relationship Analysis of Nanoparticle Compounds by GA-PLS,GA-KPLS and L-M ANN 被引量:1
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作者 Hadi Noorizadeh Abbas Farmany Mehrab Noorizadeh 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第4期569-573,共5页
Genetic algorithm and partial least square(GA-PLS),kernel PLS(KPLS) and Levenberg-Marquardt artificial neural network(L-M ANN) techniques were used to investigate the correlation between retention time(RT) and... Genetic algorithm and partial least square(GA-PLS),kernel PLS(KPLS) and Levenberg-Marquardt artificial neural network(L-M ANN) techniques were used to investigate the correlation between retention time(RT) and descriptors for 15 nanoparticle compounds obtained by the comprehensive two-dimensional gas chromatography system(GC × GC).Application of the dodecanethiol monolayer-protected gold nanoparticle(MPN) column was for a high-speed separation as the second column of GC × GC.The L-M ANN model with the final optimum network architecture of [13-5-1] gave a significantly better performance than the other models.This is the first research on the quantitative structure-retention relationship(QSRR) of nanoparticle compounds using the GA-PLS,GA-KPLS and L-M ANN. 展开更多
关键词 nanoparticle compounds comprehensive two-dimensional gas chromatography system monolayer-protected gold nanoparticle genetic algorithm-kernel partial least squares Levenberg-Marquardt artificial neural network
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若干类联图的邻点可约边标号
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作者 李敬文 孙亮晶 +1 位作者 黄聪 王江 《华中师范大学学报(自然科学版)》 北大核心 2025年第6期878-885,共8页
对于一个简单无向连通图G(V,E),若存在映射f:E(G)→{1,2,…,|E|},且对于图中所有相邻且度相同的顶点,都有标号和相同,则称f为图G的邻点可约边标号(AVREL).本文在学习研究已有图标号算法的基础上,设计了一种启发式搜索算法,利用该算法对1... 对于一个简单无向连通图G(V,E),若存在映射f:E(G)→{1,2,…,|E|},且对于图中所有相邻且度相同的顶点,都有标号和相同,则称f为图G的邻点可约边标号(AVREL).本文在学习研究已有图标号算法的基础上,设计了一种启发式搜索算法,利用该算法对15个顶点以内的联图进行标号,得到了邻点可约边标号的结果集,接着分析结果集,总结圈图与路图、星图和完全图形成的各类联图在有限点内的标号规律,并给出相关定理及证明。 展开更多
关键词 圈图 联图 邻点可约边标号 标号算法
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基于高斯过程回归的船舶DMCC发动机整机性能优化
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作者 蒋更红 才正 +1 位作者 范金宇 黄加亮 《上海海事大学学报》 北大核心 2025年第2期121-128,152,共9页
针对柴油发动机推进特性下的中高负荷工况出现的NO_(x)排放峰值现象,以及燃油价格日益上涨带来降低油耗率的迫切需求,本研究通过调节柴油/甲醇组合燃烧(diesel/methanol compound combustion,DMCC)发动机多种控制参数,在保证动力性前提... 针对柴油发动机推进特性下的中高负荷工况出现的NO_(x)排放峰值现象,以及燃油价格日益上涨带来降低油耗率的迫切需求,本研究通过调节柴油/甲醇组合燃烧(diesel/methanol compound combustion,DMCC)发动机多种控制参数,在保证动力性前提下,实现NO_(x)排放和有效燃油消耗率(brake specific fuel consumption,BSFC)的同步下降。为避免大规模试验带来的成本增加,首先基于高斯过程回归建立DMCC发动机排放的NO_(x)体积分数、BSFC和指示功率预测模型;然后将所建模型与第二代非支配排序遗传算法(non-dominated sorting genetic algorithm-Ⅱ,NSGA-Ⅱ)结合,对NO_(x)的体积分数和BSFC进行优化,并将Pareto前沿解集代入逼近理想解排序法(the technique for order preference by similarity to an ideal solution,TOPSIS)寻找最优控制参数组合;最后将最优控制参数组合标定至电子控制单元,与原机数据进行对比分析。结果表明:基于高斯过程回归建立的预测模型的拟合优度大于0.95,均方根误差小于1,具有良好的一致性和准确性;使用NSGA-Ⅱ获取的最佳控制参数与优化前(原机工况)的相比,NO_(x)的排放量下降74.5%,仅为3.47 g/(kW·h),BSFC平均下降6.7%,仅为203.5 g/(kW·h)。 展开更多
关键词 船舶柴油机 柴油/甲醇组合燃烧 高斯过程回归 第二代非支配排序遗传算法(NSGA-Ⅱ) 逼近理想解排序法(TOPSIS)
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基于复合混沌序列的计算机信息加密算法分析
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作者 刘微 刘冰洲 《微型电脑应用》 2025年第11期238-241,263,共5页
互联网高速发展的当下,计算机信息的加密方法被人们关注。由于图片载有大量信息,所以易被攻击者关注。为了计算机信息的安全,在复合混沌序列中引入压缩技术,将图像由二维转换至一维,在其中引入量子遗传算法,将融合算法在Encrypt数据集... 互联网高速发展的当下,计算机信息的加密方法被人们关注。由于图片载有大量信息,所以易被攻击者关注。为了计算机信息的安全,在复合混沌序列中引入压缩技术,将图像由二维转换至一维,在其中引入量子遗传算法,将融合算法在Encrypt数据集上进行实验,并与复合混沌序列算法、量子遗传算法、黄金正弦算法进行比较。实验结果说明,所提出的算法在加密后,像素之间的相关性均值为0.13%,其他3种算法分别为1.52%、0.86%和0.94%。面对差分攻击时,融合算法被破译后的像素均值为(-1,5),与源图像相差87%,表明所提出的算法在保密计算机信息方面的性能卓越,能有效对抗差分攻击。 展开更多
关键词 复合混沌序列 计算机信息加密算法 压缩技术 量子遗传算法 限制均值
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一种干扰环境下线阵复合成像引信目标识别算法 被引量:1
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作者 高铭泽 徐立新 +5 位作者 施小龙 王伟翰 王凤杰 胡诗苑 吴沿江 陈慧敏 《兵工学报》 北大核心 2025年第7期227-235,共9页
为解决激光成像引信在烟雾、扬尘和伪装干扰下目标识别性能差的问题,提出一种线阵激光/线阵近红外复合成像目标识别算法。根据成像模型确立标定矩阵,得到激光点云与近红外图像的空间映射关系。构建了基于深度学习的目标识别算法框架,在... 为解决激光成像引信在烟雾、扬尘和伪装干扰下目标识别性能差的问题,提出一种线阵激光/线阵近红外复合成像目标识别算法。根据成像模型确立标定矩阵,得到激光点云与近红外图像的空间映射关系。构建了基于深度学习的目标识别算法框架,在数据输入层提出了一种体素融合模块,通过编码近红外像素级特征以增强点云,在中间层提出了一种鸟瞰图视角融合模块实现特征级融合,自适应动态调节双模态特征权重。基于自建的仿真数据集对算法进行验证,实验结果表明所提出的算法能够显著提高烟雾、扬尘和伪装干扰下的目标识别精度。 展开更多
关键词 复合成像引信 目标识别 激光点云 近红外图像 融合算法
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基于惩罚法接触模型的Cu/Al复合板轧制界面动态复合过程数值模拟
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作者 孙其美 覃志伟 +2 位作者 赵辰辰 孙亚波 王涛 《中国表面工程》 北大核心 2025年第1期182-194,共13页
数值模拟是金属复合板轧制过程分析的有力工具,然而目前模拟异种金属层状板冷轧复合的数值模型大多采用界面绑定或摩擦约束。难以对界面动态复合进行判定和模拟,较难反映复合板真实的应力应变场以及实现宏观翘曲、厚度比的高精度预测,... 数值模拟是金属复合板轧制过程分析的有力工具,然而目前模拟异种金属层状板冷轧复合的数值模型大多采用界面绑定或摩擦约束。难以对界面动态复合进行判定和模拟,较难反映复合板真实的应力应变场以及实现宏观翘曲、厚度比的高精度预测,并且在单道次大压下率下易出现网格畸变严重、计算不收敛等问题,从而制约了轧制复合仿真领域的融合发展。提出了一种新的数值模型,其中的Cu/Al板有限元建模部分采用一种长宽比大于等于2的细长形网格,并且改进先前复合判据在力学行为上只考虑法线方向的不足,引入了切向力限制条件,更好地描述了法向力和切向力综合作用的实际轧制复合过程。该模型可实现对40%~60%压下率区间内,2∶4、3∶3、4∶2厚度比Cu/Al板的轧制复合模拟和宏观样貌表征,同时实现对复合板翘曲度板形和轧后厚度比的高精度模拟,翘曲度的误差均小于7.40%,轧后厚度比误差一般小于10%。模型初步解决了单道次大压下率下的严重网格畸变和计算不收敛问题,此外,在评估层状金属板复合质量和进一步探究轧制复合内在作用机制等方面有良好的发展潜力。 展开更多
关键词 复合板轧制 数值模拟 惩罚接触算法 有限元法 轧制复合判据
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自适应双阻尼小波字典的轴承复合故障诊断方法 被引量:1
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作者 胡俊锋 赵丽娟 +1 位作者 严雪竹 张龙 《振动与冲击》 北大核心 2025年第7期239-246,共8页
针对强背景噪声下难以准确提取出轴承复合故障中各故障类型有效特征的问题,提出一种基于最大相关峭度解卷积(maximum correlated kurtosis deconvolution,MCKD)和稀疏表征的轴承复合故障诊断方法。该方法首先通过MCKD算法实现复合故障... 针对强背景噪声下难以准确提取出轴承复合故障中各故障类型有效特征的问题,提出一种基于最大相关峭度解卷积(maximum correlated kurtosis deconvolution,MCKD)和稀疏表征的轴承复合故障诊断方法。该方法首先通过MCKD算法实现复合故障的分离,并达到初步增强故障冲击特征的效果;然后进行稀疏表征字典设计先验知识分析,构造与真实故障脉冲响应更加匹配的双阻尼非对称小波参数字典,结合正交匹配追踪算法,稀疏重构出各故障特征;最后对重构分量做包络谱分析,提取轴承故障特征频率。考虑到MCKD算法和非对称小波中的参数选取决定着最终的特征提取效果,使用鲸鱼优化算法实现参数自动优化选取。仿真数据和试验台数据分析结果表明,所提出的方法可有效提取出轴承复合故障中的各类故障成分,且相比常用的单阻尼Laplace小波字典具有一定的优越性。 展开更多
关键词 复合故障 最大相关峭度解卷积(MCKD)算法 双阻尼非对称小波 稀疏分解 特征提取
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关联规则挖掘补益药方配伍规律
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作者 陈星鑫 聂斌 +1 位作者 苗震 杨洋 《现代信息科技》 2025年第13期119-123,128,共6页
为挖掘ETCM(The Encyclopedia of Traditional Chinese Medicine)数据库知识,以及挖掘其他中医用药规律、古籍配伍规律提供参考,以小承气汤和厚朴大黄汤配伍组方规律为研究实例,通过Apriori算法和分析软件IBM SPSS Modeler 14.1,通过支... 为挖掘ETCM(The Encyclopedia of Traditional Chinese Medicine)数据库知识,以及挖掘其他中医用药规律、古籍配伍规律提供参考,以小承气汤和厚朴大黄汤配伍组方规律为研究实例,通过Apriori算法和分析软件IBM SPSS Modeler 14.1,通过支持度得到频繁项集,再用置信度得到关联规则,从而挖掘中药复方配伍规律。支持度值并不高,这可能与样本数(配方数)有关,但从置信度可以发现,补益药配伍有一些药经常联用。ETCM数据库具有丰富的知识,关联分析是一种挖掘中药复方配伍规律的有效方法。 展开更多
关键词 ETCM APRIORI算法 中药复方配伍规律
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邹伯奇《乘方捷术》对年月日利率关系的新认识
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作者 廖运章 《内蒙古师范大学学报(自然科学版)》 2025年第4期400-408,共9页
借贷行为是人类经济社会发展到一定阶段出现的一种经济现象,在中国社会较早流行。利息发生于借贷,是借贷关系的核心,数学简牍典籍中文字记载最早的借贷取息问题源自岳麓书院藏秦简《数》。因历代律典对复利一般令行禁止,记载借贷复利算... 借贷行为是人类经济社会发展到一定阶段出现的一种经济现象,在中国社会较早流行。利息发生于借贷,是借贷关系的核心,数学简牍典籍中文字记载最早的借贷取息问题源自岳麓书院藏秦简《数》。因历代律典对复利一般令行禁止,记载借贷复利算法的存世文献典籍有限。晚清邹伯奇《乘方捷术》首次发现并揭示,在复利情形下,年利率均分为月利率或日利率时,会导致利息的不等值,至今仍有现实意义。 展开更多
关键词 邹伯奇 《乘方捷术》 借贷算法 复利
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基于DBO优化MCKD-VMD的齿轮轴承复合故障特征提取
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作者 马亮 王靖岳 +1 位作者 郑永灿 丁建明 《车辆与动力技术》 2025年第3期45-54,共10页
针对齿轮箱复合故障传输路径复杂,早期故障振动信号微弱,易被背景噪声淹没而特征提取困难等问题,提出了基于蜣螂优化算法(dung beetle optimizer,简称DBO)优化最大相关峭度解卷积(maximum correlated kurtosis deconvolution,简称MCKD)... 针对齿轮箱复合故障传输路径复杂,早期故障振动信号微弱,易被背景噪声淹没而特征提取困难等问题,提出了基于蜣螂优化算法(dung beetle optimizer,简称DBO)优化最大相关峭度解卷积(maximum correlated kurtosis deconvolution,简称MCKD)和变分模态分解(variational mode decomposition,简称VMD)的方法用来提取齿轮箱中齿轮轴承复合故障特征.为实现MCKD和VMD的参数自适应选取,采用DBO对两种算法中的参数进行寻优.首先以包络熵为评价指标,选取MCKD所需的参数组合,利用参数优化的MCKD增强故障特征;其次利用参数优化的VMD对增强信号进行分解,构建多尺度排列熵指标筛选有效模态分量进行重构降噪;最后对重构信号进行包络解调提取故障特征.通过与DBO-MCKD和DBO-MCKD-EEMD两种方法对比分析,仿真信号和齿轮箱中齿轮轴承复合故障模拟实验均验证了该方法可以有效的提取齿轮箱中齿轮轴承复合故障特征. 展开更多
关键词 齿轮箱复合故障 蜣螂优化算法 最大相关峭度解卷积 变分模态分解 多尺度排列熵
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复合随机需求下基于阈值策略的库存分配模型研究
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作者 崔利刚 谢文静 +1 位作者 吴有 杨京昊 《重庆师范大学学报(自然科学版)》 北大核心 2025年第1期1-13,共13页
在订单驱动的库存决策中,需求订单的到达常呈现出双重随机叠加的特点,即需求订单的随机到达和需求规模的随机呈现。为解决此背景下常见的库存问题,考虑了需求到达和规模符合复合随机条件下备件库存的最优分配问题。具体来看,在周期检查(... 在订单驱动的库存决策中,需求订单的到达常呈现出双重随机叠加的特点,即需求订单的随机到达和需求规模的随机呈现。为解决此背景下常见的库存问题,考虑了需求到达和规模符合复合随机条件下备件库存的最优分配问题。具体来看,在周期检查(S,T)订货策略下以备件库存系统为研究对象,研究在复合随机需求条件下,基于阈值策略的积压需求清理机制建立缺货成本高和低2类需求的库存分配模型,实现库存成本最小化。在模型求解上,不同于之前的研究仅采用枚举法,本文应用了改进遗传算法,并设计了一种简单、高效的启发式算法。数值实验结果表明,启发式算法在求解所建立的2类模型都表现出了更好的求解效果,阈值策略比先到先服务和库存分割策略有明显的降本优势;敏感性分析证明阈值策略的相对成本优势随检查期、到达需求规模均值增加而减少,随提前期、单位库存持有成本增加而增加。研究结果为库存的精益管理提供决策参考。 展开更多
关键词 复合随机需求 缺货成本 阈值策略 改进遗传算法 启发式算法
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