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The Effect of Resources Capabilities on Cross Functional Coordination in the Footwear Micro Industry in West Jawa
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作者 Utang Jujur 《Management Studies》 2017年第5期438-444,共7页
This study is aimed at analyzing resources capabilities and cross functional coordination, and recognizes the effect of resources capabilities on cross functional coordination in the footwear micro industry in West Ja... This study is aimed at analyzing resources capabilities and cross functional coordination, and recognizes the effect of resources capabilities on cross functional coordination in the footwear micro industry in West Jawa. The author conducted descriptive survey and quatitative study to determine the level of relationship of different variables on population and to measure the contribution of free variables to restricted variables. The result shows that the resources capabilities, including leather raw materials, synthetic raw materials, funding, human resources, science management, and information and technology influence cross functional coordination in footwear micro industry in West Jawa. This study also reveals that significant resources capabilities elements include leather raw materials, funding, and human resources supplies, while other elements provided insignificant impact. 展开更多
关键词 resources capabilities cross functional coordination MSME FOOTWEAR
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基于改进Crossformer的自适应多尺度电力时间序列数据预测模型
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作者 曾孟佳 郑康伟 《计算机时代》 2025年第5期23-27,共5页
时间序列预测在电力系统运行、能源调度和设备维护中具有重要应用价值,但其面临多尺度信息利用不充分、动态分布偏移与异常噪声干扰等挑战。本文提出一种基于AMSC(自适应多适度Crossformer)架构的深度学习模型,通过多尺度特征融合框架... 时间序列预测在电力系统运行、能源调度和设备维护中具有重要应用价值,但其面临多尺度信息利用不充分、动态分布偏移与异常噪声干扰等挑战。本文提出一种基于AMSC(自适应多适度Crossformer)架构的深度学习模型,通过多尺度特征融合框架提取不同时间粒度特征,借助跨尺度规范化层缓解分布偏移,并采用自适应损失函数抑制异常值影响。与三个基准模型进行预测对比实验,结果显示,AMSC在不同数据集上均能有效完成预测任务,且预测误差更小。 展开更多
关键词 时间序列预测 多尺度架构 跨尺度规范化 自适应损失函数
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Fast Computation of Cross-Ambiguity Function 被引量:3
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作者 卓智海 单涛 陶然 《Journal of Beijing Institute of Technology》 EI CAS 2008年第4期466-471,共6页
A novel method based on zoom fast Fourier transform(FFT) is proposed for minimizing the burden processing of cross-ambiguity functions without affecting performance. The low-pass anti-aliasing filter in zoom FFT is ... A novel method based on zoom fast Fourier transform(FFT) is proposed for minimizing the burden processing of cross-ambiguity functions without affecting performance. The low-pass anti-aliasing filter in zoom FFT is realized by using the multistage filtering technique and the weighting processing is employed in the first stage filter to get rid of the redundancy of the computation. In practical systems, the input data is divided into overlapped data frames to avoid loss of detection ability which results in the rapid increase of computational complexity. A segment technique is also proposed in which CAF calculation of overlapped data frames is viewed as slide window FFT to decrease the computational complexity. The experimental results show that compared to the conventional methods, the proposed method can lower computational complexity and is consistent with the real time implementation in existing high-speed digital processors. 展开更多
关键词 cross-ambiguity function pre-weight zoom fast Fourier transform (FFT) multistage filtering
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Cross-frequency network analysis of functional brain connectivity in temporal lobe epilepsy 被引量:1
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作者 Hai-TaoYu Li-Hui Cai +3 位作者 Xin-Yu Wu Jiang Wang Jing Liu Hong Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第4期392-400,共9页
In this study, we investigate the cross-frequency coupling and functional brain networks in the subjects with temporal lobe epilepsy(TLE) using interictal EEG signals. The phase to phase synchronization within and acr... In this study, we investigate the cross-frequency coupling and functional brain networks in the subjects with temporal lobe epilepsy(TLE) using interictal EEG signals. The phase to phase synchronization within and across frequency bands is calculated and a significant difference between the epilepsy and control groups is observed. Compared with the controls,the epilepsy patients exhibit a stronger within-frequency coupling(WFC) within theta and beta bands, and shows a stronger cross-frequency coupling(CFC) in the delta–alpha and theta–alpha band pairs, but a weakened CFC in alpha–beta band pairs. The weakened coupling between alpha and high frequency band reflects a suppression of phase modulation between the brain regions related to epilepsy. Moreover, WFC and CFC are positively correlated, which is higher in the patients relative to controls. We further reconstruct functional brain connectivity and find that both WFC and CFC networks show small-world properties. For the epilepsy, the small-world efficiency is enhanced in the CFC networks in delta–alpha and theta–alpha band pairs, whereas weakened between alpha and beta bands, which suggests a shift away from the optimal operating point in the epileptic brain with a new balance between WFC and CFC. Our results may help us to understand the important role of information communication across different frequency bands and shed new light on the study of pathology of epilepsy. 展开更多
关键词 cross-frequency coupling EPILEPSY functionAL CONNECTIVITY phase SYNCHRONIZATION
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Application of Weighted Cross-Entropy Loss Function in Intrusion Detection 被引量:3
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作者 Ziyun Zhou Hong Huang Binhao Fang 《Journal of Computer and Communications》 2021年第11期1-21,共21页
The deep learning model is overfitted and the accuracy of the test set is reduced when the deep learning model is trained in the network intrusion detection parameters, due to the traditional loss function convergence... The deep learning model is overfitted and the accuracy of the test set is reduced when the deep learning model is trained in the network intrusion detection parameters, due to the traditional loss function convergence problem. Firstly, we utilize a network model architecture combining Gelu activation function and deep neural network;Secondly, the cross-entropy loss function is improved to a weighted cross entropy loss function, and at last it is applied to intrusion detection to improve the accuracy of intrusion detection. In order to compare the effect of the experiment, the KDDcup99 data set, which is commonly used in intrusion detection, is selected as the experimental data and use accuracy, precision, recall and F1-score as evaluation parameters. The experimental results show that the model using the weighted cross-entropy loss function combined with the Gelu activation function under the deep neural network architecture improves the evaluation parameters by about 2% compared with the ordinary cross-entropy loss function model. Experiments prove that the weighted cross-entropy loss function can enhance the model’s ability to discriminate samples. 展开更多
关键词 cross-Entropy Loss function Visualization Analysis Intrusion Detection KDD Data Set ACCURACY
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Reflection on Teaching Language from Analysis of Interpersonal Function in Cross-cultural Conversations
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作者 胡筱蓉 《海外英语》 2015年第6期243-244,共2页
The interpersonal function in Halliday's system-functional grammar can instruct and apply to many-sided language communication.The article is aimed at analyzing language function reflected in the conversations bet... The interpersonal function in Halliday's system-functional grammar can instruct and apply to many-sided language communication.The article is aimed at analyzing language function reflected in the conversations between international students in different cultural background and native speakers,and then getting reflections on classroom teaching language. 展开更多
关键词 cross-CULTURAL CONVERSATIONS INTERPERSONAL function TEACHING LANGUAGE
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Exploration of functional health, mental well-being and cross-sex hormone use in a sample of Thai male-to-female transgendered persons (kathoeys)
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作者 Louis J Gooren Tanapong Sungkaew Erik J Giltay 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第2期280-285,I0009,I0010,共8页
Transgender people sometimes use cross-sex hormones without medical supervision. The use of cross-sex hormones, as well as the functional health and mental well-being, among male-to-female transgendered people ('kat... Transgender people sometimes use cross-sex hormones without medical supervision. The use of cross-sex hormones, as well as the functional health and mental well-being, among male-to-female transgendered people ('kathoeys') in Chiang Mai, Thailand, was studied. Sixty kathoeys were interviewed regarding their use of cross-sex hormones and their familyrelationships. Individuals also completed the Life Orientation Test Revised (LOT-R) to assess dispositional optimism, the Social Functioning Questionnaire (SFQ) and the Short Form Health Survey 36 (SF-36). Three categories were established as follows: those who never cross-dress, those who sometimes cross-dress and those who always cross-dress in public. Of the 60 subjects, 44 had used hormones for prolonged periods (9.7+6.1 years). Their use was related to the permanence of cross-dressing but unrelated to functional health and mental well-being. Fifty percent of subjects had overdosed on commonly used oral contraceptives. Three people used injectable oestrogen in a higher-than-recommended dose. Self-acceptance was high or reasonably good (83%) compared to no acceptance (17%), and neither was related to the permanence of cross-dressing. Their acceptance by parents and siblings was also relatively high (85% and 89%, respectively). The permanence of cross-dressing had no effect on the scores of optimism, SF-36 scores and social functioning. Acceptance by oneself or one's parents did not seem to affect most aspects of functional health and mental well-being, but non-acceptance by siblings generated lower scores on the social functioning and general mental health subscales. Stressors tended to include physical rather than social factors. In conclusion, the unsupervised use of cross-sex hormones was common among kathoeys, and 50% of the sample had overdosed on them. Acceptance was relatively good, except by siblings. New strategies are needed for a more responsible use of cross-sex hormones. 展开更多
关键词 cross-sex hormones functional health kathoeys OPTIMISM TRANSGENDER WELL-BEING
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Lepton Scattering Cross Section and Nuclear Structure Function of <sup>4</sup>He and <sup>12</sup>C Nuclei
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作者 Mir Hamid Musavi Negin Sattary Nikkhoo Farhad Zolfagharpour 《World Journal of Nuclear Science and Technology》 2013年第4期131-135,共5页
This paper is an effort to extract the structure function, the EMC ratio, and the lepton scattering cross section in the convolution nuclear theory framework for 4He and 12C nuclei. We suppose that, in conventional ap... This paper is an effort to extract the structure function, the EMC ratio, and the lepton scattering cross section in the convolution nuclear theory framework for 4He and 12C nuclei. We suppose that, in conventional approach, based on harmonic oscillator model, one could consider for a nucleus shell different hw?parameters which are associated with the square root of the mean radius of the nucleus shells. We use GRV free nucleon structure function, which has good agreement with the proton and neutron structure function, extracted from experimental results. In addition, the lepton scattering cross sections of 4He and 12C nuclei are calculated in energy higher than 1 GeV. The extracted results show good agreement with experimental data. 展开更多
关键词 Structure function Differential cross SECTION The EMC Effect
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基于声纹识别的变压器故障检测方法 被引量:1
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作者 李章维 周浩 +1 位作者 郑文皓 陈毅恒 《浙江工业大学学报》 北大核心 2025年第3期293-298,共6页
由于传统的变压器故障检测方法通过专业技术人员根据设备运行声音判断故障类型与故障位置,存在一定的局限性和主观性,因此提出了一种利用变压器声音的纹理特征进行故障诊断的方法。在利用x-vector的基础上,针对变压器故障负样本数据获... 由于传统的变压器故障检测方法通过专业技术人员根据设备运行声音判断故障类型与故障位置,存在一定的局限性和主观性,因此提出了一种利用变压器声音的纹理特征进行故障诊断的方法。在利用x-vector的基础上,针对变压器故障负样本数据获取困难、数据量少的特点,引入抑制过拟合和改善交叉熵损失函数方法,解决内部数据分类不平衡的问题,准确实现变压器的故障识别。 展开更多
关键词 变压器故障 声纹识别 x-vector 交叉熵损失函数
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颈淋巴结清扫损伤指数量表的汉化及信效度检验
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作者 任晓波 田梓蓉 +3 位作者 刘永玲 韦昌韵 金晓婷 许亚红 《护理研究》 北大核心 2025年第7期1138-1143,共6页
目的:汉化颈淋巴结清扫损伤指数(NDII)量表,并在头颈肿瘤行颈淋巴结清扫术(ND)病人中检验其信效度。方法:根据自我报告量表跨文化调适指南,经前译、整合、回译、专家委员会评定和预调查对NDII量表进行汉化。采用便利抽样方法,选取2024年... 目的:汉化颈淋巴结清扫损伤指数(NDII)量表,并在头颈肿瘤行颈淋巴结清扫术(ND)病人中检验其信效度。方法:根据自我报告量表跨文化调适指南,经前译、整合、回译、专家委员会评定和预调查对NDII量表进行汉化。采用便利抽样方法,选取2024年3月—2024年5月在首都医科大学附属北京同仁医院复诊的113例头颈肿瘤行颈淋巴结清扫术病人为研究对象,使用汉化后的NDII量表进行调查,检验其信效度。结果:中文版NDII量表各条目水平的内容效度指数为0.857~1.000,全体一致性量表水平的内容效度指数为0.900,平均量表水平的内容效度指数为0.986。以肩关节功能评价量表(CMS)、健康调查简表(SF-36)及颈部功能作为效标,NDII量表与CMS得分高度相关(r=0.817,P<0.01),与SF-36的躯体疼痛(BP)维度及生理机能(PF)维度中度相关(r=0.648,P<0.01;r=0.661,P<0.01),与颈部功能疼痛评分弱相关(r=-0.340,P<0.01),以颈部功能正常与否分组的两组头颈肿瘤行颈淋巴结清扫术病人NDII量表得分差异有统计学意义(P<0.01)。NDII量表的Cronbach's α系数为0.901,重测信度为0.959。结论:中文版NDII量表为单维度量表,具有良好的信效度,且操作性良好,可作为头颈肿瘤行颈淋巴结清扫术病人颈肩功能及相关生活质量测评的特异性评估工具。 展开更多
关键词 颈淋巴结清扫术 颈肩功能 跨文化调适 信度 效度 量表
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Configuration of propagator method for calculation of electron velocity distribution function in gas under crossed electric and magnetic fields
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作者 Hirotake SUGAWARA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第9期1-18,共18页
This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic f... This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic fields crossed at a right angle. Velocity space is divided into cells with respect to three polar coordinates v,θ and f. The number of electrons in each cell is stored in three-dimensional arrays. The changes of electron velocity due to acceleration by the electric and magnetic fields and scattering by gas molecules are treated as intercellular electron transfers on the basis of the Boltzmann equation and are represented using operators called the propagators or Green’s functions. The collision propagator, assuming isotropic scattering, is basically unchanged from conventional PMs performed under electric fields without magnetic fields. On the other hand, the acceleration propagator is customized for rotational acceleration under the action of the Lorentz force. The acceleration propagator specific to the present cell configuration is analytically derived. The mean electron energy and average electron velocity vector in a model gas and SF6 were derived from the EVDF as a demonstration of the PM under the Hall deflection and they were in a fine agreement with those obtained by Monte Carlo simulations. A strategy for fast relaxation is discussed, and extension of the PM for the EVDF under AC electric and DC/AC magnetic fields is outlined as well. 展开更多
关键词 PROPAGATOR method ELECTRON velocity distribution function ELECTRON transport COEFFICIENTS crossED electric and magnetic fields MAGNETIZED plasma BOLTZMANN equation
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基于多复合测井参数的复杂岩性核主元识别方法——以开鲁盆地陆西凹陷九佛堂组储层为例 被引量:1
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作者 裴家学 郭晗 +5 位作者 周立国 张甲明 田涯 李皓 李雪英 隋强 《大庆石油地质与开发》 北大核心 2025年第2期136-146,共11页
开鲁盆地陆西凹陷九佛堂组储层复杂岩性与测井曲线之间存在非线性响应关系,致使常规岩性识别方法存在多解性和不确定性。为此引入4个与储层岩性相关的复合测井参数,增强测井曲线描述复杂岩性非线性响应特征能力;结合高斯核函数和多项式... 开鲁盆地陆西凹陷九佛堂组储层复杂岩性与测井曲线之间存在非线性响应关系,致使常规岩性识别方法存在多解性和不确定性。为此引入4个与储层岩性相关的复合测井参数,增强测井曲线描述复杂岩性非线性响应特征能力;结合高斯核函数和多项式核函数各自的优良特性,构建组合核函数,改善核主元分析方法的全局识别能力;采用K-折交叉验证法确定合理的核半径参数,从而建立一套基于多复合测井参数表征的复杂岩性核主元识别方法。实际岩性数据测试分析结果表明,引入多复合测井参数后,复杂岩性数据在核主元空间具有显著的线性可分性,岩性相对位置集中、固定且区带划分标准明确,表明该岩性划分方法具有良好的稳定性,后验识别符合率92.7%以上,证明该方法在复杂岩性识别中的有效性。研究成果为开鲁盆地复杂岩性区的岩性精确识别提供了一种新的技术思路。 展开更多
关键词 核主元分析 岩性识别 复合测井参数 组合核函数 K-折交叉验证法
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Analysis of Dynamic Cross Response between Spindles in a Dual Spindle Type Multi-Functional Turning Machine
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作者 Y. H. Choi S. T. Kim +1 位作者 T. Y. Seo K. H. Kim 《Journal of Power and Energy Engineering》 2013年第7期20-24,共5页
In order to meet increasing demand for higher productivity and flexibility, recently many kinds of multi-functional machine tools, which are capable of multiple machining functions or different kinds of machining proc... In order to meet increasing demand for higher productivity and flexibility, recently many kinds of multi-functional machine tools, which are capable of multiple machining functions or different kinds of machining processes on one machine, have been developed and widely used in manufacturing industries. In this study, a multi-functional turning lathe, which has two spindles and two turrets so that multiple turning operations and various machining processes could be performed simultaneously, has been developed. Furthermore, the equations of correlation between whole responses and cross responses of the two spindles have been derived to examine to what extent the two spindles affect each other’s vibrations. 展开更多
关键词 Multi-functional LATHE Multi-Spindles Frequency RESPONSE cross RESPONSE FEM Structural ANALYSIS
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基于混合分位数回归长短期记忆神经网络的风电功率短期区间预测 被引量:2
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作者 杨茂 张书天 +1 位作者 王勃 于欣楠 《太阳能学报》 北大核心 2025年第2期582-590,共9页
为进一步提升风电功率区间预测精度,提出一种基于混合分位数回归长短期记忆神经网络的风电功率短期区间预测方法。通过同时考虑复合、平滑和非交叉3个特点对传统分位数回归模型进行改进,首先使用平滑函数代替弹球损失函数,使长短期记忆... 为进一步提升风电功率区间预测精度,提出一种基于混合分位数回归长短期记忆神经网络的风电功率短期区间预测方法。通过同时考虑复合、平滑和非交叉3个特点对传统分位数回归模型进行改进,首先使用平滑函数代替弹球损失函数,使长短期记忆神经网络更易于拟合分位数回归模型。然后构建复合目标函数,使其能在给出多个分位数的条件下不重复训练多个独立模型。接着利用ReLU罚函数进行非交叉约束来避免分位数交叉现象的发生。最后将改进后的分位数回归与长短期记忆神经网络相结合并应用于中国甘肃省某风电场,运行结果表明所提模型在不同置信水平下对应PICP和PIAW分别提高了4.17个百分点和降低了2.31 MW,验证了方法的有效性。 展开更多
关键词 风电功率 深度学习 区间预测 复合非交叉 分位数回归 ReLU罚函数
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奇异谱分析与小波变换改进的弱磁检测方法研究
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作者 刘伟 常青 王耀力 《仪表技术与传感器》 北大核心 2025年第5期81-87,共7页
为满足日益增长的地下弱磁信号检测需求,文中提出了一种交叉验证增强的时间延迟嵌入奇异值分解(CV-TE-SVD)算法和小波变换改进的标准正交基(WT-OBF)磁异常检测方法。CV-TE-SVD算法通过时间延迟嵌入将实测磁场数据形成相应的轨迹矩阵,并... 为满足日益增长的地下弱磁信号检测需求,文中提出了一种交叉验证增强的时间延迟嵌入奇异值分解(CV-TE-SVD)算法和小波变换改进的标准正交基(WT-OBF)磁异常检测方法。CV-TE-SVD算法通过时间延迟嵌入将实测磁场数据形成相应的轨迹矩阵,并结合交叉验证优化奇异值选择,使得重构结果既保留目标信号的主体特征,又对噪声做了滤波处理,提高了信号重构的精度。WT-OBF方法利用小波变换的多分辨率分析能力,在不同尺度上分析信号,捕捉到不同频率成分,从而提升了磁异常信号的检测精度和鲁棒性。实验结果表明:CV-TE-SVD算法在不同距离下均表现出优异的性能,平均重构误差约为0.08,改进的WT-OBF算法信噪比(SNR)平均提升4.85 dB,在3倍物径距下的SNR最大提升了7.20 dB,其检测性能显著高于OBF算法和实测数据,为地下弱磁信号检测提供了技术支持。 展开更多
关键词 地下弱磁检测 奇异谱分析 正交基函数 小波变换 交叉验证
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基于分段评价遗传算法的移动机器人路径规划
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作者 谢嘉 孙帅浩 +3 位作者 李永国 梁锦涛 金昌兵 陈学飞 《传感技术学报》 北大核心 2025年第6期1064-1071,共8页
针对传统遗传算法在处理路径规划问题时存在适应性差、收敛速度慢和易早熟等问题,提出一种基于分段评价路径的改进遗传算法。设计一种动态权重适应度函数,在线调节参数并考虑坡度因素,来增强算法对复杂环境的适应能力;提出一种新的交叉... 针对传统遗传算法在处理路径规划问题时存在适应性差、收敛速度慢和易早熟等问题,提出一种基于分段评价路径的改进遗传算法。设计一种动态权重适应度函数,在线调节参数并考虑坡度因素,来增强算法对复杂环境的适应能力;提出一种新的交叉变异方式,分段评价个体后进行有选择性的交叉和变异,提升算法的寻优能力,加快收敛速度;采用模糊控制在线调节交叉变异概率,避免算法早熟;引入删除算子剔除冗余节点,提高最优解的平滑性;在20×20和30×30地图环境上进行仿真实验,结果表明所提算法具有更强的适应能力,改进型交叉变异能更快地搜索到更优路径,在线调节交叉变异概率很好地避免了算法早熟,最终解在路径长度、收敛速度及平滑度上均有提升。 展开更多
关键词 路径规划 分段评价路径 改进遗传算法 动态权重适应度函数 选择性交叉变异 模糊控制
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基于FDTRP-ALDCNN的小样本轴承故障诊断方法
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作者 王娜 刘佳林 王子从 《铁道科学与工程学报》 北大核心 2025年第9期4271-4283,共13页
针对滚动轴承在小样本条件下诊断精度低的问题,提出一种基于频域无阈值递归图与自适应线性可变卷积神经网络(frequency domain thresholdless recurrence plot-adaptive linear deformable convolutional neural network,FDTRP-ALDCNN)... 针对滚动轴承在小样本条件下诊断精度低的问题,提出一种基于频域无阈值递归图与自适应线性可变卷积神经网络(frequency domain thresholdless recurrence plot-adaptive linear deformable convolutional neural network,FDTRP-ALDCNN)的滚动轴承故障诊断方法。首先,使用快速傅里叶变换(fast fourier transform,FFT)将一维时域信号转为频域信号,并与无阈值递归图(thresholdless recurrence plot,TRP)相结合,以有效构建初始特征,提高模型输入质量;其次,采用线性可变卷积核(linear deformable convolutional kernel,LDConv)替换卷积神经网络中方形卷积核,从而能够根据采样数据的分布来调整卷积核形状,准确获取空间信息中的关键特征,提高小样本数据的利用率;再次,设计自适应交叉熵(adaptive cross entropy,ACE)损失函数,根据样本分类损失自适应调整分类器对难分与易分样本的拟合程度,增强难分样本损失在整体分类损失中的显著性,进一步提高小样本下的模型诊断精度;最后,采用CWRU滚动轴承数据集对所提方法进行3组仿真验证。对比仿真的结果表明,所提模型在不同小样本数量下均有较高的诊断准确率,最高可达到99.82%。而对2组不平衡数据集的泛化性分析可知,本模型的诊断准确率分别达到98.56%与99.3%,泛化能力优于其他模型,且具有良好的稳定性。并通过消融实验验证了FFT、LDConv与ACE损失函数对提高故障诊断精度的有效性。综上所述,所提方法能够有效诊断出小样本轴承故障,具有较高的实际应用价值。 展开更多
关键词 故障诊断 小样本 无阈值递归图 线性可变卷积核 卷积神经网络 交叉熵损失函数
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规则截面无限长柱体的光散射研究
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作者 颜兵 张华永 +1 位作者 陈平 刘晨华 《激光技术》 北大核心 2025年第1期62-66,共5页
为了研究任意规则截面的无限长柱体对入射光束的散射特性,提出了一种半解析方法。采用适当的圆柱矢量波函数来展开散射场和内场,通过电磁场边界条件和投影法确定展开系数;以基模高斯光束和径向环状光束照射横截面为圆形、椭圆形和矩形... 为了研究任意规则截面的无限长柱体对入射光束的散射特性,提出了一种半解析方法。采用适当的圆柱矢量波函数来展开散射场和内场,通过电磁场边界条件和投影法确定展开系数;以基模高斯光束和径向环状光束照射横截面为圆形、椭圆形和矩形的无限长柱体为例,对归一化的近场强度分布进行了数值仿真。结果表明,光束经过圆柱和椭圆柱传输后发生明显的干涉现象,而矩形柱对光束具有一定的汇聚作用。该研究为求解任意规则横截面的无限长柱体对任意光束的散射提供了一个应用方便的半解析解。 展开更多
关键词 散射 干涉现象 半解析方法 规则截面无限长柱体 圆柱矢量波函数 归一化场强分布
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养家动机影响因素的组态分析:基于人-境互动的视角 被引量:1
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作者 李伟贺 张亚静 +1 位作者 夏宇欣 商士杰 《中国临床心理学杂志》 北大核心 2025年第1期45-50,共6页
目的:基于人-境互动的视角,探究影响养家动机的多重并发因果关系。方法:通过间隔8周的两阶段问卷调查,获得340份已婚职工样本。首先,采用交叉-滞后模型检验情境变量家庭功能对养家动机的影响;其次,采用模糊集定性比较分析(fsQCA)来检验... 目的:基于人-境互动的视角,探究影响养家动机的多重并发因果关系。方法:通过间隔8周的两阶段问卷调查,获得340份已婚职工样本。首先,采用交叉-滞后模型检验情境变量家庭功能对养家动机的影响;其次,采用模糊集定性比较分析(fsQCA)来检验个体变量(性别、家庭自尊)和情境变量(有无孩子、家庭财务压力、家庭功能)的组态对养家动机的影响。结果:(1)家庭功能正向影响员工的养家动机;(2)发现两条导致高养家动机的因素组态(Y1:gender*ESTEEM*FINANCE*function;Y2:~GENDER*child*finance*FUNCTION)和三条导致低养家动机的因素组态(N1:child*~esteem*~FINANCE*~FUNCTION;N2:gender*~esteem*~FINANCE*~FUNCTION;N3:gender*child*~FINANCE*~FUNCTION)。结论:家庭经济因素和情感因素是驱动养家动机的重要情境因素。对于高家庭自尊的男性,经济因素更具激励作用;对于有孩子的女性,情感因素更具激励作用。 展开更多
关键词 养家动机 家庭功能 交叉-滞后分析 组态分析 人-境互动
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长江中下游降水分区的季节特征及其对大气环流的响应 被引量:1
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作者 李函珂 董晓华 +4 位作者 马耀明 龚成麒 李璐 冷梦辉 苏中波 《水文》 北大核心 2025年第3期86-92,共7页
探究长江中下游流域季节降水的时空特征及其对大气环流的响应,可以揭示气候变化对流域内异常降水的影响,对进一步准确预估流域旱涝灾情有重要意义。研究基于长江中下游1978—2017年总计40a的日降雨数据,采用旋转经验正交分解函数(Rotate... 探究长江中下游流域季节降水的时空特征及其对大气环流的响应,可以揭示气候变化对流域内异常降水的影响,对进一步准确预估流域旱涝灾情有重要意义。研究基于长江中下游1978—2017年总计40a的日降雨数据,采用旋转经验正交分解函数(Rotated Empirical Orthogonal Function,REOF)以及非参数Mann-Kendall检验等趋势突变检验方法,分析了研究区季节尺度降水的时空变化特征,并结合交叉小波法分析研究区不同季节降水对典型北半球大尺度大气环流的响应。结果显示:(1)在未来,春季降水易在中部Ⅰ区异常增加;夏季降水易在东南Ⅱ区异常增加;秋季降水易在东北Ⅲ区异常增加;冬季降水易在西南Ⅳ区异常减少。(2)春季降水与四种大气环流高度相关,秋季降水不易受环流因子影响,夏、冬季流域东北地区降水易受影响。AO主要影响冬季降水,PDO易影响春、冬季降水,SOI对夏季降水影响大。流域季节降水对大气环流的响应由南部及东北地区逐渐向西北地区递减;(3)东南Ⅱ区春、秋季降水不可预测性强,夏季降水极端且趋于增加,冬季异常降水影响大且关联小麦种植,需重点关注气候变化对东南地区降水的影响。以上结论可为区域季节性降水灾害防治提供潜在的预测因子,并有助于及时应对区域旱涝灾情,可提高灾害防治措施的针对性和效果。 展开更多
关键词 长江中下游 季节降水 大气环流 旋转经验正交方程 交叉小波变换
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