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Transfer-free CVD graphene for highly sensitive glucose sensors 被引量:1
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作者 Shijing Wei Yabin Hao +7 位作者 Zhe Ying Chuan Xu Qinwei Wei Sen Xue Hui-Ming Cheng Wencai Ren Lai-Peng Ma You Zeng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第2期71-76,共6页
Chemical vapor deposition(CVD)graphene film is a promising electrode-modifying material for fabricating high-performance glucose sensor due to its high electrical conductivity and two-dimensional structure over large ... Chemical vapor deposition(CVD)graphene film is a promising electrode-modifying material for fabricating high-performance glucose sensor due to its high electrical conductivity and two-dimensional structure over large area.However,the use of typical metal-based CVD graphene suffers from the residue contamination of polymer transfer-support and heavy metal ions.In this work,we directly grew fewlayer graphene on the SiO2/Si substrate without transfer process and then fabricated graphene-based glucose sensors by sequentially immobilizing glucose oxidase and depositing Nafion layer on its surface that was functionalized by oxygen-plasma treatment.Our transfer-and metal-free process shows distinct advantage over the common metal-CVD method in improving the electrochemical performance by eliminating the contamination of transfer-residue.Thus-obtained glucose sensor shows a high sensitivity(16.16μA mM-1cm-2)with a detection limit of 124.19μM.This method is simple and promising for the development of highly sensitive glucose sensors. 展开更多
关键词 GRAPHENE Chemical vapor DEPOSITION transfer-free Oxygen-plasma treatment GLUCOSE sensor
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Farmers' Land Transfer-out Behavior from the Perspective of Household Livelihood Endowment Based on the Survey in Anhui,Hubei and Sichuan 被引量:2
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作者 Zhangjin FEI 《Asian Agricultural Research》 2018年第6期23-29,共7页
Based on the household livelihood endowment theory and the survey of 367 farmer households in Anhui,Hubei,and Sichuan in 2016,and using the orderly multi-category logistic model,the behavioral decision of farmers in t... Based on the household livelihood endowment theory and the survey of 367 farmer households in Anhui,Hubei,and Sichuan in 2016,and using the orderly multi-category logistic model,the behavioral decision of farmers in the land circulation was discussed to explore the key parameters influencing the land transfer-out. It found that decisions of farmers on land transfer-out behavior are affected by many factors.Specifically,household non-agricultural income and per capita land area significantly reduce farmers' willingness to transfer land,while the household head age,agricultural input-output ratio,and confirmation of land right significantly promote the farmers' decision on land transferout. Therefore,increasing the allocation efficiency of household livelihood endowment has important policy value and practical significance for eliminating unreasonable land circulation and promoting large-scale agricultural production. 展开更多
关键词 Household livelihood endowment Land transfer-out Orderly multi-category logistic model
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On U(1) Gauge Theory Transfer-Matrix in Fourier Basis
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作者 Narges Vadood Amir H.Fatollahi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第8期921-926,共6页
The properties of the transfer-matrix of U(1) lattice gauge theory in the Fourier basis are explored.Among other statements it is shown:(i) the transfer-matrix is block-diagonal,(ii) all consisting vectors of a block ... The properties of the transfer-matrix of U(1) lattice gauge theory in the Fourier basis are explored.Among other statements it is shown:(i) the transfer-matrix is block-diagonal,(ii) all consisting vectors of a block are known based on an arbitrary block vector,(iii) the ground-state belongs to the zero-mode’s block.The emergence of maximum-points in matrix-elements as functions of the gauge coupling is clarified.Based on explicit expressions for the matrix-elements we present numerical results as tests of our statements. 展开更多
关键词 LATTICE GAUGE theories transfer-MATRIX method energy SPECTRUM
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Study of a mass transfer-reaction model for SO_2 absorption process using LAS/H_2SO_4 solution
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作者 Yue Changtao Li Shuyuan +3 位作者 Chen Weihong Guo Shaohui Yang Yuhua Sha Yingxun 《Petroleum Science》 SCIE CAS CSCD 2010年第3期397-402,共6页
A regenerative absorption process for removal of SOx from FCC off-gas using LAS/ H2SO4 solution as absorbant was studied and pilot-plant experiments were carried out. A mass transfer- reaction model for the SO2 absorp... A regenerative absorption process for removal of SOx from FCC off-gas using LAS/ H2SO4 solution as absorbant was studied and pilot-plant experiments were carried out. A mass transfer- reaction model for the SO2 absorption process was established based on pilot-plant experiments, and the concentration distribution of components in the liquid film, and the partial pressure and mass transfer rate of SO2 along the height of the absorption tower, was calculated from this model. The numerical simulation results were compared with the experimental results and proved that the model can be used for describing the SO2 absorption process. 展开更多
关键词 Regenerative absorption process SOx cleanup LAS/H2SO4 solution mass transfer-reactionmodel
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Cu(0) Wire-mediated Single-electron Transfer-living Radical Polymerization of Oligo(ethylene oxide) Methyl Ether Acrylate by Selecting the Optimal Reaction Conditions
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作者 Liang Ding Juan Li +3 位作者 Rui-Yu Jiang Ling-Fang Wang Wei Song Lei Zhu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第11期1130-1141,共12页
The efficient Cu(0) wire-catalyzed single-electron transfer-living radical polymerization (SET-LRP) in organic solvents and mixtures of the organic solvents with water has been thoroughly investigated. 01igo(ethylene ... The efficient Cu(0) wire-catalyzed single-electron transfer-living radical polymerization (SET-LRP) in organic solvents and mixtures of the organic solvents with water has been thoroughly investigated. 01igo(ethylene oxide) methyl ether acrylate was used as an exemplar oligomer monomer to determine the optimum polymerization conditions for rapid, controlled, and quantitative production of well-defined polymers. The effects of Cu(0)-wire length (12.5 or 4.5 cm), ligand type (tris(dimethylaminoethyl)amine, Me6-TREN, or tris(2-aminoethyl)amine, TREN), and solvent type (dipolar aprotic solvents, cyclic ethers, alcohol, or acetone) on the polymerization have been evaluated. Kinetic experiments were performed for all polymerizations to assess the "living" behavior of each system employed. Importantly, TREN could be used as a replacement for Me6-TREN in Cu(0) wire-catalyzed SET-LRP of oligomer monomer, which probably provides the most economical and efficient methodology since TREN is 80 times less expensive than Me6-TREN. The high chain-end fidelity of resulting polymer was experimentally verified by thiol-Michael addition reaction at the a-Br chain end and subsequent chain extension with methyl acrylate. 展开更多
关键词 SINGLE-ELECTRON transfer-living RADICAL POLYMERIZATION Oligo(ethylene oxide) methyl ETHER ACRYLATE Kinetics of POLYMERIZATION Modification
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A Simple but Accurate Ultraviolet Limb-Scan Spherically-Layered Radiative-Transfer-Model Based on Single-Scattering Physics 被引量:3
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作者 郭霞 吕达仁 吕曜 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期619-630,共12页
Here we present a study focusing on atmospheric limb-scattered radiative characteristics in the ultraviolet band by using a limb-scan spherically-layered radiative-transfer-model based on the single-scattering approxi... Here we present a study focusing on atmospheric limb-scattered radiative characteristics in the ultraviolet band by using a limb-scan spherically-layered radiative-transfer-model based on the single-scattering approximation, which was developed by the present authors. We have applied an accurate numerical integration technique involving an auto-adaptive modified-space step, which assured high accuracy and simplification. Comparisons were made to the newly released spherical radiative transfer model, SCIATRAN2.0, which was developed by Institute of Remote Sensing/Institute of Environmental Physics (IUP/IFE) at University of Bremen and to measurements collected via an ultraviolet spectrometer on the Solar Mesospheric Explorer (SME) satellite, which was launched in October, 1981. Preliminary results indicate that the present model provides a good interpretation of the earth-limb scattered ultraviolet radiance, and thus, is suitable for the study of the ultraviolet-limb radiative-transfer problem with high accuracy. 展开更多
关键词 ULTRAVIOLET limb geometry spherical atmosphere radiative-transfer model
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基于Transfer-SVM多标签文本分类算法研究 被引量:2
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作者 李程文 宋文广 谭建平 《无线互联科技》 2019年第10期102-103,共2页
传统的支持向量机分类模型只有在利用大量已标注数据进行训练才能获得较高精度。在实际应用中,多标签数据相对于传统单标签数据更具有价值,但多标签数据中含有大量冗余数据,获取大量多标签数据难度非常大。文章提出一种基于迁移学习的... 传统的支持向量机分类模型只有在利用大量已标注数据进行训练才能获得较高精度。在实际应用中,多标签数据相对于传统单标签数据更具有价值,但多标签数据中含有大量冗余数据,获取大量多标签数据难度非常大。文章提出一种基于迁移学习的分类算法,利用目标数据域和源数据域的相关性,从源数据域中选取对分类超平面起关键作用的支持向量和目标数据域,一起训练分类模型以提高分类精度。 展开更多
关键词 多标签 迁移学习 文本分类 支持向量机
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Optimization of the Classic Transfer-Stacking Model Migration Algorithm: A Way to Solve Time-Varying Performance Degradation of Acute Kidney Injury Clinical Prediction Model
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作者 Yunfei Xue 《Journal of Biosciences and Medicines》 2021年第4期14-28,共15页
Acute Kidney Injury (AKI) is one of the most common acute and critical illnesses in general wards and intensive care units. Its high morbidity and high fatality rate have become a major global public health problem. T... Acute Kidney Injury (AKI) is one of the most common acute and critical illnesses in general wards and intensive care units. Its high morbidity and high fatality rate have become a major global public health problem. There are often serious lags in clinical diagnosis of AKI. Early diagnosis and timely intervention and effective care become critical. The use of electronic medical record data to build an AKI risk prediction model has been proven to help prevent the occurrence of AKI. However, in actual clinical applications, the distribution of historical data and new data will continue to vary over time, resulting in a significant decrease in the performance of the model. How to solve the problem of model performance degradation over time will be a core challenge for the long-term use of predictive models in clinical applications. Aiming at the above problems, this paper studies the classic Transfer-Stacking model migration algorithm. Aiming at the lack of this algorithm, such as the loss of a large amount of feature information of the target domain and poor fit when integrating the model of the target domain, the Accumulate-Transfer-Stacking algorithm is proposed to improve it. Improvements include: 1) Optimize the input vector and model integration algorithm of Transfer-Stacking’s target domain model. 2) Optimize Transfer-Stacking from a single-source domain model to a multi-source domain model. The experimental results show that for the improved algorithm proposed in this paper when the data is sufficient and insufficient, the average AUC value of the model on the data of subsequent years is 0.89 and 0.87, and the average F1 Score value is 0.45 and 0.36. Moreover, this method is significantly better than the unimproved Transfer-Stacking algorithm and baseline method, and can effectively overcome the problem of data distribution heterogeneity caused by time factors. 展开更多
关键词 Acute Kidney Injury Electronic Medical Record Risk Prediction Transfer Learning
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Transfer-Learning for Automated Seizure Detection Based on Electric Field Encephalography Reconstructed Signal
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作者 Gefei Zhu 《Communications and Network》 2020年第4期174-198,共25页
Building an automatic seizure onset prediction model based on multi-channel electroencephalography (EEG) signals has been a hot topic in computer science and neuroscience field for a long time. In this research, we co... Building an automatic seizure onset prediction model based on multi-channel electroencephalography (EEG) signals has been a hot topic in computer science and neuroscience field for a long time. In this research, we collect EEG data from different epilepsy patients and EEG devices and reconstruct and combine the EEG signals using an innovative electric field encephalography (EFEG) method, which establishes a virtual electric field vector, enabling extraction of electric field components and increasing detection accuracy compared to the conventional method. We extract a number of important features from the reconstructed signals and pass them through an ensemble model based on support vector machine (SVM), Random Forest (RF), and deep neural network (DNN) classifiers. By applying this EFEG channel combination method, we can achieve the highest detection accuracy at 87% which is 6% to 17% higher than the conventional channel averaging combination method. Meanwhile, to reduce the potential overfitting problem caused by DNN models on a small dataset and limited training patient, we ensemble the DNN model with two “weaker” classifiers to ensure the best performance in model transferring for different patients. Based on these methods, we can achieve the highest detection accuracy at 82% on a new patient using a different EEG device. Thus, we believe our method has good potential to be applied on different commercial and clinical devices. 展开更多
关键词 EEG Seizure Detection Transfer Learning Deep Neural Network Electric Field Encephalography
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TRANSFER-MATRIX METHOD FOR SURFACE SPIN WAVES IN A SEMI-INFINITE MAGNETIC SUPERLATTICE WITH A SINGLE-ION ANISOTROPY
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作者 李振亚 沈文忠 《苏州大学学报(自然科学版)》 CAS 1992年第2期176-184,共9页
Surface spin waves in a semi-infinite magnetre super lattice with a single-ion uniaxial anisotropy are investigated through the transfer mafrix method.The dispersion equations of surface spin wavs are obfained.We find... Surface spin waves in a semi-infinite magnetre super lattice with a single-ion uniaxial anisotropy are investigated through the transfer mafrix method.The dispersion equations of surface spin wavs are obfained.We find that not all the magnetic superlattice structures can excite the surface spin waves,and that the anisotropy term need not be favorable to the excitation of surface spin wavs,but surely influences the values of the energy of the excited surface spin waves. 展开更多
关键词 转移矩阵法 表面旋转波 超点阵 磁性材料 各向异性 离子
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3C智能制造工厂的AGV智慧物料传输与调度综述 被引量:7
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作者 孙孝飞 郭捷 +4 位作者 魏灿名 金翔 赵飞 王磊 梅雪松 《中南大学学报(自然科学版)》 北大核心 2025年第2期514-535,共22页
介绍了3C行业智能制造的发展现状与趋势,总结了3C智能制造过程中物料传输与调度的技术要求、现状问题与发展趋势。在此基础上,通过分析AGV的技术发展及其在智能工厂的应用进展,重点探讨了3C智能制造工厂中AGV物料传输与调度的关键技术,... 介绍了3C行业智能制造的发展现状与趋势,总结了3C智能制造过程中物料传输与调度的技术要求、现状问题与发展趋势。在此基础上,通过分析AGV的技术发展及其在智能工厂的应用进展,重点探讨了3C智能制造工厂中AGV物料传输与调度的关键技术,包括AGV物料传输任务数据库、路径规划、多机协同调度、动态调度管控、AGV调度管理系统等。最后,对3C智能制造工厂的AGV智慧物料传输与调度技术进行了总结和展望,提出了5G(第五代移动通信技术)+人工智能物联网(AIoT)以及高集成化的技术趋势,以促进3C制造业的数智化、高效化发展。 展开更多
关键词 3C制造 物料传输 AGV 动态调度 智能化
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汉江经济带生态系统服务价值空间流转及生态补偿研究 被引量:5
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作者 张静 宋晓玲 +2 位作者 胡仪元 徐增让 王鹏涛 《长江流域资源与环境》 北大核心 2025年第2期320-330,共11页
汉江生态经济带是我国南水北调中线工程水源区,加强其生态系统服务价值空间流转及生态补偿研究,对于推进区域生态文明建设,促进生态产品价值转化具有重要意义。采用生态系统服务价值当量因子法、生态补偿优先级指数和空间自相关分析法等... 汉江生态经济带是我国南水北调中线工程水源区,加强其生态系统服务价值空间流转及生态补偿研究,对于推进区域生态文明建设,促进生态产品价值转化具有重要意义。采用生态系统服务价值当量因子法、生态补偿优先级指数和空间自相关分析法等,在测算生态系统服务价值的基础上,评估了汉江经济带生态补偿优先级、生态补偿额度和比较生态辐射力大小,揭示了区域生态系统服务供给状况及空间流转特征。结果表明:(1)1990~2020年汉江生态经济带各县区单位面积生态系统服务价值多年平均值在82.64~491.19万元/km^(2),内部空间差异大。(2)从县域尺度来看,单位面积生态系统服务价值空间集聚性呈微下降倾向,局部集聚显著。(3)研究区生态补偿总额度理论值为235.34亿元,占汉江经济带国内生产总值的0.97%,上游汉中市、安康市、商洛市、十堰市和神农架林区生态补偿总额占总补偿额度的80.97%。(4)十堰市比较生态辐射力较大,对研究区中下游城市的生态贡献度高,应建立横向生态补偿机制,推进上下游形成流域协同治理与统筹发展。总体来看,汉江生态经济带生态系统服务价值内部差异大,从生态补偿优先级角度,进行生态补偿空间识别及生态补偿额度确定是指导流域生态补偿可资借鉴的方法,也为建立横向生态补偿机制提供了理论基础和实践指导。 展开更多
关键词 生态服务价值 生态补偿标准 空间流转 汉江生态经济带
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基于改进YOLOv8m的稻田害虫识别方法 被引量:4
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作者 谭泗桥 陈涵 +4 位作者 朱磊 孙浩然 张政兵 尹丽 黄婉婉 《农业工程学报》 北大核心 2025年第2期185-195,共11页
为解决现有基于机器视觉的稻田害虫监测过程中存在的检测速度慢、小目标检测精度低、害虫堆积遮挡时检测精度低以及样本不平衡等问题,该研究提出了一种基于改进YOLOv8m模型的稻田害虫识别方法FieldSentinel-YOLOv8。该方法首先简化了YOL... 为解决现有基于机器视觉的稻田害虫监测过程中存在的检测速度慢、小目标检测精度低、害虫堆积遮挡时检测精度低以及样本不平衡等问题,该研究提出了一种基于改进YOLOv8m模型的稻田害虫识别方法FieldSentinel-YOLOv8。该方法首先简化了YOLOv8m模型,并用双检测头代替三检测头,以减少小目标细粒度信息的丢失,降低模型的复杂度;其次将卷积注意力模块CBAM(convolutional block attention module)添加到YOLOv8m,使模型抑制背景等一般特征信息,更加关注害虫区域,从而提高被遮挡害虫的识别准确率;最后使用Focal-CIoU Loss来替换CIoU Loss(complete intersection over union),以减少样本类别不平衡对模型精度的影响。FieldSentinel-YOLOv8模型的平均精度均值(mean average precisoin)mAP_(0.5)为73.64%,精确率为65.43%,召回率为75.17%,检测帧率为199.88帧/s。与原模型YOLOv8m相比,FieldSentinel-YOLOv8的模型参数量从25.86 M(million)降到10.34 M,所需浮点运算数从79.10 G(1 G=109)降到62.80 G,召回率、平均精度均值和检测帧率分别提升7.05、2.72个百分点和52.73帧/s。该研究还采用Pest24数据集作为源域,自建数据集作为目标域的迁移学习方法训练FieldSentinel-YOLOv8模型,得到高精度FieldSentinelTransferYOLOv8模型,进一步提升模型检测性能,使用迁移学习方法后,m AP_(0.5)再次提升3.36个百分点,达到77.00%,精确率为69.90%,召回率为77.73%。在自建数据集上进行模型对比试验,结果表明,FieldSentinel-YOLOv8模型具有较高的识别准确率及较强的鲁棒性,该模型的轻量化方法可为农业害虫的精准且快速识别提供技术参考。高精度FieldSentinelTransfer-YOLOv8模型精度的大幅提升,也表明迁移学习在农业害虫检测上提供了技术支持。 展开更多
关键词 虫害 深度学习 图像识别 YOLOv8m 卷积注意力模块 Focal-CIoU 迁移学习
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农场道路图层构建和农机转移路径规划方法与试验 被引量:3
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作者 高锐涛 资乐 +5 位作者 胡炼 何杰 汪沛 黄培奎 谢佳生 刘善琪 《华南农业大学学报》 北大核心 2025年第2期256-264,共9页
【目的】针对农场内农机转移依赖人工驾驶或人工打点及规划耗时费力且不满足无人化应用需求等问题,提出一种无人农场农机转移路径规划方法。【方法】利用ArcGIS构建农场道路图层和路网,进行仿真试验;开发基于图论的Dijkstra双向搜索的... 【目的】针对农场内农机转移依赖人工驾驶或人工打点及规划耗时费力且不满足无人化应用需求等问题,提出一种无人农场农机转移路径规划方法。【方法】利用ArcGIS构建农场道路图层和路网,进行仿真试验;开发基于图论的Dijkstra双向搜索的转移路径规划算法,利用Python进行单、双向搜索仿真;搭建基于web平台的转移路径规划系统。【结果】在路网的仿真中,农机在0.7 m/s的速度下从机库到田块、田块到田块、田块到机库的行驶距离分别为241.57、74.46和75.66 m,对应时间分别为345.10、106.37和108.09 s。Dijkstra算法的单、双向搜索用时分别为0.632和0.216 s,在运算效率上双向搜索较单向搜索提升了65.82%。基于web平台的转移路径规划系统的农机以0.7 m/s的速度从机库到田块、田块到田块和田块到机库进行了实车道路试验,路径与农机实际路径采样点的算术平均值差值绝对值小于0.1 m,可以满足无人农场农机的转移要求。相对于人工打点,转移路径规划系统的路径规划效率更高。【结论】构建的农场道路图层、路网和转移路径规划系统,满足无人农场农机的道路转移需求。研究结果可为无人农场的农机转移路径提供技术支持。 展开更多
关键词 无人农场 农场道路图层 路网 转移路径规划系统
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基于改进Res2Net与迁移学习的水果图像分类 被引量:3
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作者 吴迪 肖衍 +2 位作者 沈学军 万琴 陈子涵 《电子科技大学学报》 北大核心 2025年第1期62-71,共10页
针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成... 针对传统水果图像分类算法特征学习能力弱和细粒度特征信息表示不强的缺点,提出一种基于改进Res2Net与迁移学习的水果图像分类算法。首先,针对网络结构,在Res2Net的残差单元中引入动态多尺度融合注意力模块,对各种尺寸的图像动态地生成卷积核,利用meta-ACON激活函数优化ReLU激活函数,动态学习激活函数的线性和非线性,自适应选择是否激活神经元;其次,采用基于模型迁移的训练方式进一步提升分类的效率与鲁棒性。实验结果表明,该算法在Fruit-Dataset和Fruits-360数据集上的测试准确率相比Res2Net提升了1.2%和1.0%,召回率相比Res2Net提升了1.13%和0.89%,有效提升了水果图像分类性能。 展开更多
关键词 图像分类 Res2Net 动态多尺度融合注意力 激活函数 迁移学习
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基于跨时间尺度迁移学习的污水处理模型漂移校正方法 被引量:1
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作者 申渝 廖万山 +6 位作者 李慧敏 冯东 郭智威 张冰 高旭 王建辉 陈猷鹏 《环境科学》 北大核心 2025年第1期318-326,共9页
数据是智能运维的核心基础,但当前污水厂数据普遍不足,且污水处理系统状态随内外部环境动态演化.污水厂的智能运维面临着建模难度大,及因系统演化而导致的模型漂移问题.针对该问题,选取水温、水质和微生物状态等都有显著差异的夏冬两季... 数据是智能运维的核心基础,但当前污水厂数据普遍不足,且污水处理系统状态随内外部环境动态演化.污水厂的智能运维面临着建模难度大,及因系统演化而导致的模型漂移问题.针对该问题,选取水温、水质和微生物状态等都有显著差异的夏冬两季作为典型对比场景,将机制模型与神经网络结合,建立了基于跨时间尺度迁移学习的污水处理模型漂移校正方法 .首先,针对数据不足问题,建立并校准活性污泥模型(ASM),以夏季工况数据作为输入,模拟计算运行参数和出水数据,生成模拟运行数据集,实现数据增广和质量提升,用于训练多层感知机神经网络(MLP)模型.结果显示,MLP模型对夏季出水COD、氨氮和总磷等的平均模拟准确率在95%以上;然后,针对模型在冬季工况中出现模拟准确率大幅下降等模型漂移问题,将冬季实测数据作为目标域数据集,以MLP模型作为预训练模型进行迁移学习.结果表明,迁移学习后模型性能显著提升,出水COD、氨氮、总氮和总磷的平均模拟准确率分别提高了21.49%、60.79%、58.14%和46.74%.研究提出的跨时间尺度迁移学习方法,能有效解决模型漂移问题,实现模型对污水处理系统动态演化的跟随响应. 展开更多
关键词 多层感知机神经网络(MLP)模型 机制模型 迁移学习 模型漂移 系统适应性 知识迁移
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数字经济赋能农村产业现代化的内在逻辑、现实挑战及优化路径 被引量:18
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作者 刘学侠 徐文哲 温啸宇 《中国流通经济》 北大核心 2025年第1期14-24,共11页
在数字经济迅猛发展的当今时代,各行各业都迎来了新的变革机遇。农村产业体系作为我国经济的基础产业体系,也应把握数字时代新机遇,为发展注入新动力。数字经济赋能农村产业现代化具有全链路深度覆盖的特征。从作用机理看,数字经济依托... 在数字经济迅猛发展的当今时代,各行各业都迎来了新的变革机遇。农村产业体系作为我国经济的基础产业体系,也应把握数字时代新机遇,为发展注入新动力。数字经济赋能农村产业现代化具有全链路深度覆盖的特征。从作用机理看,数字经济依托物联网、大数据、人工智能(AI)、生物技术等新兴数字技术,对技术研发、品种繁育、种植养殖到生产加工、物流、销售等农业产业链全过程赋能,促进农业生产的优质化、品牌化、产业化、集约化、规模化、专业化、社会化、绿色化,进而助力乡村产业现代化进程。这不仅能够提升农业生产效率和产品质量,还能够促进农业产业间的融合发展,增强农业产业的整体竞争力。从发展模式看,我国当前的农业经营主体占比最大的仍然是小农户,如何实现小农户与现代农业的有机衔接是农村产业现代化进程中的关键问题。得益于数字经济广覆盖、高效率、非竞争性等特性,通过建立农业社会化服务体系,提供技术支持和市场信息服务,可以帮助小农户提高生产效率,降低成本,增加收入;通过数字技术推动农业产业链的延伸、强化和补充,即“延链”“强链”“补链”,可以帮助小农户将生产活动从种养环节向农产品加工流通等二三产业延伸,提高农户综合收益;通过改善供产销之间的衔接效率,实现订单形势变化与生产组织方式的高度匹配,可以帮助小农户充分发挥资源优势,转化为市场竞争力;通过土地流转的数字化管理,可以帮助小农户提升规模化经营水平,进而提升发展质量;通过数据分析预测作物病虫害发生,可以帮助小农户进行科学农业生产决策,指导精准灌溉施肥,减少资源浪费。 展开更多
关键词 数字经济 农村产业现代化 农业产业链 土地流转
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活性染料墨水配制及在棉织物冷转印中的应用 被引量:1
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作者 彭勇刚 纪俊玲 +1 位作者 陶永新 汪媛 《针织工业》 北大核心 2025年第3期21-25,共5页
以市售的活性染料无盐色浆为着色剂,通过分析染料质量分数、添加剂用量与墨水性能间的关系,得到墨水配方为:活性染料无盐色浆14.0%~18.0%、乙二醇10.0%、乙醇7.5%、乙二醇丁醚5.0%、烷基糖苷0.4%~0.6%、其余为去离子水,并用三乙醇胺调... 以市售的活性染料无盐色浆为着色剂,通过分析染料质量分数、添加剂用量与墨水性能间的关系,得到墨水配方为:活性染料无盐色浆14.0%~18.0%、乙二醇10.0%、乙醇7.5%、乙二醇丁醚5.0%、烷基糖苷0.4%~0.6%、其余为去离子水,并用三乙醇胺调节pH值至8.0~8.5。将其用于纯棉织物薄膜转移印花,探讨涂层剂种类及用量、碳酸钠质量分数、转印压力、汽蒸时间对印花效果的影响,获得转印最佳工艺条件,转印织物的耐摩擦、耐皂洗色牢度均超过4级。 展开更多
关键词 活性染料 墨水 薄膜 转移印花
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基于响应面法-遗传算法的船舶推进轴系多目标优化设计 被引量:2
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作者 张聪 疏炳南 +1 位作者 张江涛 金勇 《上海交通大学学报》 北大核心 2025年第4期466-475,I0001,共11页
为降低船舶在航行过程中传动设备的功率损失,提高推进轴系的传递效率,并改善轴系振动性能,基于响应面模型与遗传算法(GA)对某船舶轴系实验台进行了多目标优化设计.采用星点设计(CCD)方法,在优化设计空间中选取合理实验点,拟合构建最小... 为降低船舶在航行过程中传动设备的功率损失,提高推进轴系的传递效率,并改善轴系振动性能,基于响应面模型与遗传算法(GA)对某船舶轴系实验台进行了多目标优化设计.采用星点设计(CCD)方法,在优化设计空间中选取合理实验点,拟合构建最小总功耗和振动响应幅值的响应面模型.基于GA,利用MATLAB软件求解响应面模型回归函数的Pareto最优解.对比分析各组优化结果,获得最佳优化设计方案,研究结果表明采用这种联合方法后,轴系功耗损失降低了约7.10%,轴系振动幅值降低了2.30%,能有效提高轴系传递效率和抑制推进轴系振动问题,从而验证了船舶推进轴系多目标优化方法的正确性和可行性. 展开更多
关键词 推进轴系 传递效率 响应面法 遗传算法
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新兴领域军民两用技术转移机制、趋势与障碍因子研究 被引量:3
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作者 田庆锋 沈伟康 +2 位作者 李瑶 曾紫韬 方聪聪 《北京理工大学学报(社会科学版)》 北大核心 2025年第1期174-187,共14页
新兴领域军民两用技术的高效转移是形成新域新质作战力量的关键驱动力。通过提炼新兴领域军民两用技术转移的内涵和形成机制,以2015—2021年间145家新兴领域军民融合企业作为研究样本,采用退火算法优化投影寻踪模型及高斯核密度估计分... 新兴领域军民两用技术的高效转移是形成新域新质作战力量的关键驱动力。通过提炼新兴领域军民两用技术转移的内涵和形成机制,以2015—2021年间145家新兴领域军民融合企业作为研究样本,采用退火算法优化投影寻踪模型及高斯核密度估计分析其演化趋势,通过ICTM分析框架诊断其障碍因子。结果表明:新兴领域军民两用技术的转移通过双螺旋耦合机制和相对技术势差流向机制得以实现;新兴领域技术转移水平呈现上升趋势,存在能力跃迁现象,但不同战区间转移水平差距逐渐扩大,形成明显的“梯型效应”。研究还发现,新兴领域技术转移意愿、军民融合理念、技术要素流动性、保密机制和中介能力是影响新兴领域军民两用技术转移的关键障碍因子。本研究结果丰富了技术转移相关理论,为新兴领域军民融合发展提供参考价值。 展开更多
关键词 新兴领域 军民两用技术 转移机制 转移趋势 障碍因子
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