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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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Fast Computation of Cross-Ambiguity Function 被引量:2
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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:2
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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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全链路数字化转型过程中的组织惯性克服机制
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作者 苏敬勤 武宪云 《技术经济》 北大核心 2024年第8期74-84,共11页
数字经济时代,涵盖全场域的全链路数字化转型往往面临更广范围的历史束缚,使得传统企业深陷历史惯性囹圄,克服组织惯性成为传统企业实现数字化发展的首要任务。本文对飞鹤乳业的数字化转型实践过程进行探索性案例分析,探究传统企业全链... 数字经济时代,涵盖全场域的全链路数字化转型往往面临更广范围的历史束缚,使得传统企业深陷历史惯性囹圄,克服组织惯性成为传统企业实现数字化发展的首要任务。本文对飞鹤乳业的数字化转型实践过程进行探索性案例分析,探究传统企业全链路数字化转型过程中面临的组织惯性及其克服机制。研究发现:全链路数字化转型过程中,(1)组织惯性显现范围被扩大,企业面临跨功能认知惯性与跨功能结构惯性的变革阻力;(2)传统企业通过由外而内的资源编排方式来克服跨功能组织惯性阻力,且不同类别跨功能组织惯性克服的内在机理存在异质性。对于跨功能认知惯性克服,企业采用“外源型结构化-传承型能力化-置换型杠杆化”的资源编排策略;对于跨功能结构惯性克服,企业采用“外源型结构化-开拓型能力化-组合型杠杆化”的资源编排策略。本文不仅扩展了数字化转型情境下组织惯性的相关理论,还为传统企业成功推进数字化转型提供了实践指引。 展开更多
关键词 全链路数字化转型 跨功能组织惯性 资源编排 克服机制 案例研究
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基于阵列风速仪实测的台风“苏迪罗”近地风场空间相关性研究
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作者 张建国 刘哲瑄 雷鹰 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期504-511,共8页
[目的]针对沿海区域近地台风风场的空间相关性问题进行研究.[方法]根据阵列风速仪实测的台风“苏迪罗”风速风向数据,选取4个稳定时段的288个风速样本,对台风近地风场的空间相关性进行详细的分析.首先定性研究平均风速和风向角对顺、横... [目的]针对沿海区域近地台风风场的空间相关性问题进行研究.[方法]根据阵列风速仪实测的台风“苏迪罗”风速风向数据,选取4个稳定时段的288个风速样本,对台风近地风场的空间相关性进行详细的分析.首先定性研究平均风速和风向角对顺、横风向、垂直方向脉动风速的竖向和水平互相关系数的影响,然后分析平均风速和风向角对3种脉动风速竖向和水平相干函数的影响,最后对顺风向竖向相干函数、顺风向水平相干函数和横风向水平相干函数进行公式拟合,获得相关参数的取值.[结果]平均风速对顺、横风向的竖向和水平互相关系数及相干函数有一定影响,平均风速越大,相应的互相关系数和相干函数也随之增大;风向角对3种脉动风速的竖向相关性影响不大,但对顺、横风向的水平互相关系数和相干函数影响较大;各种相干函数在零频率处(f=0 Hz)的数值大都小于1.0,零频率处的数值随距离与平均风速的比值呈指数衰减规律;顺风向竖向相干函数、顺风向水平相干函数和横风向水平相干函数随距离与平均风速比值的衰减系数分别为9.3 f+0.38,3.1 f+0.18,3.2 f+0.16.[结论]基于阵列风速仪实测的近地台风数据,分析得到了台风风场的空间相关性特性,竖向和水平的互相关系数和相干函数,给出的拟合公式可用于大跨度空间结构和桥梁结构的动态响应分析计算,可有效评估工程结构的抗风安全性. 展开更多
关键词 台风实测 阵列布置 风速仪 互相关系数 相干函数
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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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融合残差连接的图像语义分割方法
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作者 王龙宝 张珞弦 +3 位作者 张帅 徐亮 曾昕 徐淑芳 《计算机测量与控制》 2024年第1期157-164,共8页
由于传统SegNet模型在采样过程中产生了大量信息损失,导致图像语义分割精度较低,为此提出了一种融合残差连接的新型编-解码器网络结构:文中引入了多残差连接策略,更为全面地保留了多尺度图像中包含的大量细节信息,降低还原降采样所带来... 由于传统SegNet模型在采样过程中产生了大量信息损失,导致图像语义分割精度较低,为此提出了一种融合残差连接的新型编-解码器网络结构:文中引入了多残差连接策略,更为全面地保留了多尺度图像中包含的大量细节信息,降低还原降采样所带来的信息损失;为进一步加速网络训练的收敛效率,改善样本的不平衡问题,设计了一种带平衡因子的交叉熵损失函数,对正负样本不平衡现象予以针对性的优化,使得模型的训练更加高效;实验表明该方法较好地解决了语义分割中信息损失以及分割不准确的问题,与SegNet相比,本网络在Cityscapes数据集上进行精细标注的mIoU值提高了约13%。 展开更多
关键词 语义分割 残差连接 交叉熵损失函数 SegNet模型 深度学习
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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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基于结构功能交叉神经网络的多模态医学图像融合
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作者 邸敬 郭文庆 +2 位作者 任莉 杨燕 廉敬 《光学精密工程》 EI CAS CSCD 北大核心 2024年第2期252-267,共16页
针对多模态医学图像融合中存在纹理细节模糊和对比度低的问题,提出了一种结构功能交叉神经网络的多模态医学图像融合方法。首先,根据医学图像的结构信息和功能信息设计了结构功能交叉神经网络模型,不仅有效地提取解剖学和功能学医学图... 针对多模态医学图像融合中存在纹理细节模糊和对比度低的问题,提出了一种结构功能交叉神经网络的多模态医学图像融合方法。首先,根据医学图像的结构信息和功能信息设计了结构功能交叉神经网络模型,不仅有效地提取解剖学和功能学医学图像的结构信息和功能信息,而且能够实现这两种信息之间的交互,从而很好地提取医学图像的纹理细节信息。其次,利用交叉网络通道和空间特征变化构造了一种新的注意力机制,通过不断调整结构信息和功能信息权重来融合图像,提高了融合图像的对比度和轮廓信息。最后,设计了一个从融合图像到源图像的分解过程,由于分解图像的质量直接取决于融合结果,因此分解过程可以使融合图像包含更多的细节信息。通过与近年来提出的7种高水平方法相比,本文方法的AG,EN,SF,MI,QAB/F和CC客观评价指标分别平均提高了22.87%,19.64%,23.02%,12.70%,6.79%,30.35%,说明本文方法能够获得纹理细节更清晰、对比度更好的融合结果,在主观视觉和客观指标上都优于其他对比算法。 展开更多
关键词 多模态医学图像融合 结构功能信息交叉网络 注意力机制 分解网络
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大气湍流下部分相干涡旋光束经粗糙目标回波特性
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作者 吴鹏飞 辛蕾 +1 位作者 王姣 谭震坤 《激光杂志》 CAS 北大核心 2024年第4期148-153,共6页
利用广义Huygens-Fresnel原理和随机高斯粗糙面模型,研究部分相干高斯-谢尔模型涡旋光束的回波特性,通过特殊积分推导出部分相干涡旋光束经随机粗糙面散射后到达接收端的交叉谱密度函数和光强解析式,并进行仿真分析。结果表明:随着拓扑... 利用广义Huygens-Fresnel原理和随机高斯粗糙面模型,研究部分相干高斯-谢尔模型涡旋光束的回波特性,通过特殊积分推导出部分相干涡旋光束经随机粗糙面散射后到达接收端的交叉谱密度函数和光强解析式,并进行仿真分析。结果表明:随着拓扑荷数、束腰半径和相干长度的增加,光强自相关函数曲线下降的越来越陡峭;在强湍流环境下,自相关函数衰减越来越严重;内尺度会影响光强自相关函数,并且随着内尺度的增大而衰减严重,外尺度对其影响作用不大;随着粗糙目标相干长度的增大,光强自相关函数的半峰宽值逐渐趋增大。 展开更多
关键词 光通信 大气湍流 随机高斯粗糙目标 交叉谱密度函数 散斑
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电火工品换能元性能优化的策略与展望
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作者 王力 任炜 +4 位作者 褚恩义 牛惠媛 李慧 李蛟 张文超 《火工品》 CAS CSCD 北大核心 2024年第5期1-9,I0002,共10页
伴随着高安全性、高可靠性、低能发火和高能输出等应用需求,电火工品换能元的发展经历了技术交叉、融合创新的过程。本文从电火工品换能元的发展历程、技术发展热点和发展展望3个方面对其进行了梳理总结,从内部需求牵引下的换能机制和... 伴随着高安全性、高可靠性、低能发火和高能输出等应用需求,电火工品换能元的发展经历了技术交叉、融合创新的过程。本文从电火工品换能元的发展历程、技术发展热点和发展展望3个方面对其进行了梳理总结,从内部需求牵引下的换能机制和外部技术驱动下学科交叉2个方面对电火工品换能元的发展历程进行了综合阐述。最后,从本质机理探究、安全性和可靠性兼顾、功能拓展3个方面,陈述了对电火工品换能元未来发展思路的一些见解。 展开更多
关键词 电火工品 换能元 机理探究 学科交叉 功能拓展
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改进YOLOv4的遥感图像目标检测算法 被引量:1
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作者 闵锋 况永刚 +2 位作者 毛一新 彭伟明 郝琳琳 《计算机工程与设计》 北大核心 2024年第2期396-404,共9页
为有效解决遥感图像目标检测算法在复杂背景下的检测效果不佳的问题,提出一种改进YOLOv4的目标检测算法。设计一种跨阶段残差结构,替换原主干网络的简单残差结构,降低模型参数量和计算负担;引入CBAM注意力机制,加强CSP模块间有效特征交... 为有效解决遥感图像目标检测算法在复杂背景下的检测效果不佳的问题,提出一种改进YOLOv4的目标检测算法。设计一种跨阶段残差结构,替换原主干网络的简单残差结构,降低模型参数量和计算负担;引入CBAM注意力机制,加强CSP模块间有效特征交互;使用跨阶段分层卷积模块重构特征融合阶段对深层特征图的处理方式,防止网络退化和梯度消失;采用Mish激活函数,增强融合网络对非线性特征的提取能力。在RSOD、DIOR数据集上的实验结果表明,改进YOLOv4算法的测试mAP相比原YOLOv4算法分别高出4.5%、7.3%,其检测速度分别达到48 fps、45 fps,在保证实时性的同时检测精度有较大提升。 展开更多
关键词 遥感图像 目标检测 跨阶段残差结构 特征交互 跨阶段分层卷积模块 激活函数 非线性特征
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两岸融合发展示范区建设的逻辑理路和实践进路——基于“结构-过程”框架的分析
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作者 罗海成 《闽台关系研究》 2024年第1期2-16,共15页
建设两岸融合发展示范区,是推进两岸关系和平发展和服务祖国统一大业的重大战略安排。基于结构功能主义理论,应用“结构-过程”框架,建构两岸融合发展示范区研究模型。从结构角度分析,可以清晰展现两岸融合发展示范区在内涵、空间两个... 建设两岸融合发展示范区,是推进两岸关系和平发展和服务祖国统一大业的重大战略安排。基于结构功能主义理论,应用“结构-过程”框架,建构两岸融合发展示范区研究模型。从结构角度分析,可以清晰展现两岸融合发展示范区在内涵、空间两个维度的全领域、全区域的全域网格化图景;从过程角度分析,可以动态体现两岸融合发展中两类主体、两种不同方向作用力的互动作用过程。两岸融合发展示范区建设蕴含了社会系统建构的内在逻辑机理,是两岸关系领域理论与实践相结合的创新探索。两岸融合发展示范区是一项创新性系统工程,在结构层面要强化系统观念,完善两岸融合发展示范区有机系统;在过程层面要强化合作观念,推动两岸融合发展示范区合作共建;在创新层面要强化质效观念,实现两岸融合发展示范区建设规划目标。 展开更多
关键词 两岸融合发展示范区 结构功能主义 “结构-过程” 逻辑理路 社会系统
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一类新的单参数F-C函数及其应用
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作者 李硕 尚有林 屈德强 《工程数学学报》 CSCD 北大核心 2024年第3期494-506,共13页
填充函数法作为可以有效求解多变量、多极值函数的全局最优化方法,通过交替求解目标函数和填充函数找到问题的全局最优解或近似全局最优解,其寻优能力与所采用的填充函数性质有直接关系。因此,构造具有良好数学性质的填充函数新形式一... 填充函数法作为可以有效求解多变量、多极值函数的全局最优化方法,通过交替求解目标函数和填充函数找到问题的全局最优解或近似全局最优解,其寻优能力与所采用的填充函数性质有直接关系。因此,构造具有良好数学性质的填充函数新形式一直都是填充函数法的重要研究领域。然而,当前已有的填充函数存在以下问题:填充函数不连续不可微;参数过多难以控制和调整;包含指数项或对数项。为解决上述不足,将填充函数和跨越函数相结合,引入求解无约束全局优化问题的F-C函数定义。根据此定义,构造一类新的单参数F-C函数,此参数在迭代过程中易于调节。在分析该函数理论性质的基础上,提出新的全局优化F-C函数方法,该算法打破传统填充函数算法的求解框架,成功减少求解目标函数的次数,提高计算效率。通过数值计算验证F-C函数算法的有效性和可行性。最后,用F-C函数算法对切削温度实验中的参数进行优化,并与已有结果进行比较,数值试验结果表明该算法具有更好的拟合效果。 展开更多
关键词 全局最优化 填充函数 跨越函数 F-C函数 切削温度
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基于加窗互相关函数的微动面波岩溶塌陷探测
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作者 宋同 李欣欣 +2 位作者 张伟 胡涛 郑晓慧 《中国岩溶》 CAS CSCD 北大核心 2024年第4期937-947,共11页
文章利用微动面波成像方法对江西某研究区的岩溶塌陷进行探测:先针对微动信号的互相关函数进行窗函数优化处理,提高数据信噪比,改善微动面波的频散能量谱分辨率;再对研究区各组虚源面波记录进行频散曲线提取和反演处理,获得测线上各点... 文章利用微动面波成像方法对江西某研究区的岩溶塌陷进行探测:先针对微动信号的互相关函数进行窗函数优化处理,提高数据信噪比,改善微动面波的频散能量谱分辨率;再对研究区各组虚源面波记录进行频散曲线提取和反演处理,获得测线上各点的横波速度结构;最后联合各测点反演结果生成测线下方的横波速度剖面,并结合钻孔资料进行地质解释,成功揭示区内岩溶塌陷的分布位置及深度。结果表明:(1)互相关函数计算时的窗函数选取将影响频散能量谱的分辨率,在微动数据处理时应进行窗函数测试;(2)对互相关函数进行加窗处理和优化,可有效提高微动面波的信噪比和频散能量谱的分辨率,拓宽频散曲线的频带范围,提高反演的准确性;(3)微动面波技术在岩溶塌陷探测中具有较好的应用效果,结合加窗函数优化处理能更准确确定地下危害体的范围。 展开更多
关键词 微动 面波 互相关函数 窗函数 岩溶塌陷
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新工科背景下功能材料专业多元交叉复合型人才培养探索
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作者 陈雅君 《高教学刊》 2024年第28期63-66,共4页
21世纪以来,对于材料科学与工程同其他众多高新科学技术领域交叉融合的需求逐渐提高。功能材料专业应运而生,北京工商大学的功能材料专业2019年获批建设。该文在具体方法上讨论四个方面内容,即课程模块化建设和课程组建设构建多元交叉... 21世纪以来,对于材料科学与工程同其他众多高新科学技术领域交叉融合的需求逐渐提高。功能材料专业应运而生,北京工商大学的功能材料专业2019年获批建设。该文在具体方法上讨论四个方面内容,即课程模块化建设和课程组建设构建多元交叉的课程体系;课程团队共建、教师教育背景多元化、促进教师交流合作等建设多元交叉的教师队伍;共建教学科研平台和实习实践基地及共建学生创新创业团队搭建多元交叉融合的教学资源与教学科研平台,以及强化实践教学。通过该文的实践和探索,为促进学科间相互渗透交叉、专业可持续发展及复合型优秀人才的培养提供参考。 展开更多
关键词 功能材料专业 新工科 多元交叉 复合型人才培养 课程建设
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