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TDNN:A novel transfer discriminant neural network for gear fault diagnosis of ammunition loading system manipulator
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作者 Ming Li Longmiao Chen +3 位作者 Manyi Wang Liuxuan Wei Yilin Jiang Tianming Chen 《Defence Technology(防务技术)》 2025年第3期84-98,共15页
The ammunition loading system manipulator is susceptible to gear failure due to high-frequency,heavyload reciprocating motions and the absence of protective gear components.After a fault occurs,the distribution of fau... The ammunition loading system manipulator is susceptible to gear failure due to high-frequency,heavyload reciprocating motions and the absence of protective gear components.After a fault occurs,the distribution of fault characteristics under different loads is markedly inconsistent,and data is hard to label,which makes it difficult for the traditional diagnosis method based on single-condition training to generalize to different conditions.To address these issues,the paper proposes a novel transfer discriminant neural network(TDNN)for gear fault diagnosis.Specifically,an optimized joint distribution adaptive mechanism(OJDA)is designed to solve the distribution alignment problem between two domains.To improve the classification effect within the domain and the feature recognition capability for a few labeled data,metric learning is introduced to distinguish features from different fault categories.In addition,TDNN adopts a new pseudo-label training strategy to achieve label replacement by comparing the maximum probability of the pseudo-label with the test result.The proposed TDNN is verified in the experimental data set of the artillery manipulator device,and the diagnosis can achieve 99.5%,significantly outperforming other traditional adaptation methods. 展开更多
关键词 Manipulator gear fault diagnosis Reciprocating machine Domain adaptation Pseudo-label training strategy transfer discriminant neural network
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Transnational technology transfer network in China:Spatial dynamics and its determinants 被引量:1
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作者 LIU Chengliang YAN Shanshan 《Journal of Geographical Sciences》 SCIE CSCD 2022年第12期2383-2414,共32页
Patent transfer has been regarded as an important channel for the nations and regions to acquire external technology,and also a direct research object to depict the relationship between supply and demand of technology... Patent transfer has been regarded as an important channel for the nations and regions to acquire external technology,and also a direct research object to depict the relationship between supply and demand of technology flow.Therefore,based on traceable patent transfer data,this article has established a dual-pipeline theoretical framework of transnational-domestic technology transfer from the interaction of the global and local(glocal)perspective,and combines social networks,GIS spatial analysis as well as spatial econometric model to discover the spatial evolution of China’s transnational technology channels and its determinant factors.It is found that:(1)The spatial heterogeneity of the overall network is significant while gradually weakened over time.(2)The eastward shift of the core cities involved in transnational technology channels is accelerating,from the hubs in North America(New York Bay Area,Silicon Valley,Caribbean offshore financial center,etc.)and West Europe(London offshore financial center etc.)to East Asia(Tokyo and Seoul)and Southeast Asia(Singapore),which illustrates China has decreased reliance on the technology from the USA and West Europe.(3)The four major innovation clusters:Beijing-Tianjin-Hebei region(Beijing as the hub),Yangtze River Delta(Shanghai as the hub),The Greater Bay Area(Shenzhen and Hong Kong as the hubs)and north Taiwan(Taipei and Hsinchu as the hubs),are regarded as global technology innovation hubs and China’s distribution centers in transnational technology flow.Among those,Chinese Hong Kong’s betweenness role of technology is strengthened due to linkage of transnational corporations and their branches,and low tax coverage of offshore finance,thus becoming the top city for technology transfer.Meanwhile,Chinese Taiwan’s core position is diminishing.(4)The breadth,intensity,and closeness of domestic technology transfer are conducive to the expansion of transnational technology import channels.Additionally,local economic level has positive effect on transnational technology transfer channels while technology strength and external economic linkage have multifaceted influences. 展开更多
关键词 patent rights transaction technology transfer’s dual pipelines technology transfer network spatial evolution determinant factor
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Fault Estimation and Accommodation for Networked Control Systems with Transfer Delay 被引量:24
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作者 MAO Ze-Hui JIANG Bin 《自动化学报》 EI CSCD 北大核心 2007年第7期738-743,共6页
在这份报纸,差错评价和差错的一个方法为有转移延期和进程噪音的联网的控制系统(NCS ) 的容忍的控制被介绍。首先,联网的控制系统作为有转移的分离时间的系统推迟的 multiple-input-multiple-output (MIMO ) 被建模,处理噪音,并且... 在这份报纸,差错评价和差错的一个方法为有转移延期和进程噪音的联网的控制系统(NCS ) 的容忍的控制被介绍。首先,联网的控制系统作为有转移的分离时间的系统推迟的 multiple-input-multiple-output (MIMO ) 被建模,处理噪音,并且为无常建模。在这个模型下面并且在一些条件下面,一个差错评价方法被建议估计系统差错。根据差错评价和滑动模式控制理论的信息,一个差错容忍的控制器被设计恢复系统性能。最后,模拟结果被用来验证方法的效率。 展开更多
关键词 网络控制系统 迟滞转移 容错估计 容错控制 不确定性模型 滑动模型控制
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Designing an Intelligent Control Philosophy in Reservoirs of Water Transfer Networks in Supervisory Control and Data Acquisition System Stations
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作者 Ali Dolatshahi Zand Kaveh Khalili-Damghani Sadigh Raissi 《International Journal of Automation and computing》 EI CSCD 2021年第5期694-717,共24页
In this paper, a hybrid neural-genetic fuzzy system is proposed to control the flow and height of water in the reservoirs of water transfer networks. These controls will avoid probable water wastes in the reservoirs a... In this paper, a hybrid neural-genetic fuzzy system is proposed to control the flow and height of water in the reservoirs of water transfer networks. These controls will avoid probable water wastes in the reservoirs and pressure drops in water distribution networks. The proposed approach combines the artificial neural network, genetic algorithm, and fuzzy inference system to improve the performance of the supervisory control and data acquisition stations through a new control philosophy for instruments and control valves in the reservoirs of the water transfer networks. First, a multi-core artificial neural network model, including a multi-layer perceptron and radial based function, is proposed to forecast the daily consumption of the water in a reservoir. A genetic algorithm is proposed to optimize the parameters of the artificial neural networks. Then, the online height of water in the reservoir and the output of artificial neural networks are used as inputs of a fuzzy inference system to estimate the flow rate of the reservoir inlet. Finally, the estimated inlet flow is translated into the input valve position using a transform control unit supported by a nonlinear autoregressive exogenous model. The proposed approach is applied in the Tehran water transfer network. The results of this study show that the usage of the proposed approach significantly reduces the deviation of the reservoir height from the desired levels. 展开更多
关键词 Water demand forecasting water transfer network supervisory control and data acquisition water management multicore artificial neural network fuzzy inference system
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Transfer Learning Based on Joint Feature Matching and Adversarial Networks 被引量:1
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作者 ZHONG Haowen WANG Chao +3 位作者 TUO Hongya HU Jian QIAO Lingfeng JING Zhongliang 《Journal of Shanghai Jiaotong university(Science)》 EI 2019年第6期699-705,共7页
Domain adaptation and adversarial networks are two main approaches for transfer learning.Domain adaptation methods match the mean values of source and target domains,which requires a very large batch size during train... Domain adaptation and adversarial networks are two main approaches for transfer learning.Domain adaptation methods match the mean values of source and target domains,which requires a very large batch size during training.However,adversarial networks are usually unstable when training.In this paper,we propose a joint method of feature matching and adversarial networks to reduce domain discrepancy and mine domaininvariant features from the local and global aspects.At the same time,our method improves the stability of training.Moreover,the method is embedded into a unified convolutional neural network that can be easily optimized by gradient descent.Experimental results show that our joint method can yield the state-of-the-art results on three common public datasets. 展开更多
关键词 transfer learning adversarial networks feature matching domain-invariant features
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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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Neonatal Transfer Situation Following Implementation of a Perinatal Network: An Analysis in Douala, Cameroon
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作者 Daniele Kedy Koum Diomede Noukeu Njinkui +5 位作者 Monique Carole Magnibou Loick Pradel Kojom Foko Charlotte Eposse Rhita Mbono Patricia Epée Eboumbou Calixte Ida Penda 《Open Journal of Pediatrics》 2022年第1期148-161,共14页
Background: Postnatal transfer (PT) is interhospital transport of care-needing newborns. In 2016, a perinatal network was implemented to facilitate PT in the town of Douala, Cameroon. The network was supposed to impro... Background: Postnatal transfer (PT) is interhospital transport of care-needing newborns. In 2016, a perinatal network was implemented to facilitate PT in the town of Douala, Cameroon. The network was supposed to improve PT-related care standards. This study aimed at determining characteristics of PT five years following the implementation of this network. Methods: A cross-sectional study was carried out from February to May 2021 at neonatology wards of six hospitals in Douala. Medical records of newborns transferred to the hospitals were scrutinized to document their characteristics. Parents were contacted to obtain information on PT route and itinerary. Data were analyzed using Epi Info software and summarized as percentages, mean and odds ratio. Results: In total, 234 of the 1159 newborns admitted were transferred, giving a PT prevalence of 20.2% (95% CI 17.9% - 22.6%). Male-to-female ratio of the transferred newborns was 1.3. Neonatal infection (26.5%), prematurity (23.5%) and respiratory distress (15.4%) were the main reasons for transfer. Only 3% of the PT was medicalized while only 2% of the newborns were transferred through perinatal network. On admission, hypothermia and respiratory distress were found in 31% and 35% of the newborns, respectively. The mortality rate among babies was 20% and these had a two-fold risk of dying (95% CI 1.58 - 3.44, p Conclusion: PT and the perinatal network are lowly organized and implemented in Douala. Sensitization of medical staff on in utero transfer, creating center for coordination of the network, and implementation of neonatal transport system could improve the quality of PT. 展开更多
关键词 Postnatal transfer Perinatal network Characterization Douala
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Routing in Delay Tolerant Networks (DTN)<br>—Improved Routing with MaxProp and the Model of “Transfer by Delegation” (Custody Transfer)
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作者 El Mastapha Sammou Abdelmounaim Abdali 《International Journal of Communications, Network and System Sciences》 2011年第1期53-58,共6页
In this paper, we address the problem of routing in delay tolerant networks (DTN). In such networks there is no guarantee of finding a complete communication path connecting the source and destination at any time, esp... In this paper, we address the problem of routing in delay tolerant networks (DTN). In such networks there is no guarantee of finding a complete communication path connecting the source and destination at any time, especially when the destination is not in the same region as the source, which makes traditional routing protocols inefficient in that transmission of the messages between nodes. We propose to combine the routing protocol MaxProp and the model of “transfer by delegation” (custody transfer) to improve the routing in DTN networks and to exploit nodes as common carriers of messages between the network partitioned. To implement this approach and assess those improvements and changes we developed a DTN simulator. Simulation examples are illustrated in the article. 展开更多
关键词 ROUTING Delay TOLERANT networks DTN MaxProp CUSTODY transfer Simulator
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SCHEDULE ARRANGEMENT AND OPTIMIZATION OF THE FILE TRANSFER NETWORK
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作者 潘建平 谢俊清 +1 位作者 张雪梅 邓建明 《Journal of Southeast University(English Edition)》 EI CAS 1995年第1期72-82,共11页
This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktis... This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktispan the smallestone. Three situations with 展开更多
关键词 FILE transfer network packet switchins I virtual circuit I etjges color-ing VERTEX COLORING I heuristic alsorithm
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机器学习方法预测油气产量技术发展现状及前景展望 被引量:1
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作者 谢坤 田轩硕 +5 位作者 刘长龙 邵明 刘延春 高铭宣 袁世亮 张宝岩 《特种油气藏》 北大核心 2025年第4期14-24,共11页
受油气开发过程中储层物性、流体性质和工艺措施的复杂多变性影响,生产数据的分析利用程度多取决于石油科技工作者的专业经验,计算成本和时间成本高,难以满足油气藏高效开发需求,亟待发现更加高效的油气产量预测方法。近年来,以深度神... 受油气开发过程中储层物性、流体性质和工艺措施的复杂多变性影响,生产数据的分析利用程度多取决于石油科技工作者的专业经验,计算成本和时间成本高,难以满足油气藏高效开发需求,亟待发现更加高效的油气产量预测方法。近年来,以深度神经网络、随机森林算法和迁移学习为代表的机器学习方法凭借处理高维数据、捕捉时序数据长期依赖关系和提取开发数据特征等方面的独特优势,在油气产量预测中取得了显著应用效果。该文通过对常用油气产量预测机器学习方法的原理及其优缺点进行分析,阐述了机器学习方法在油气产量预测领域的应用现状,总结了应用过程中潜在的问题,同时对油气产量预测方法的发展前景进行展望。未来,一方面应加强对物理约束融入机器学习模型的研究,提高模型的可解释性,避免过于理想化的预测结果;另一方面要开发适合小样本情况下的算法和迁移学习技术,充分利用历史生产数据,为油气产量预测提供更好的数据分析技术支持。该研究对油气产量的智能预测技术完善具有理论指导意义。 展开更多
关键词 油气田开发 产量预测 机器学习 神经网络 迁移学习
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Enhancing Pneumonia Detection in Pediatric Chest X-Rays Using CGAN-Augmented Datasets and Lightweight Deep Transfer Learning Models 被引量:1
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作者 Coulibaly Mohamed Ronald Waweru Mwangi John M. Kihoro 《Journal of Data Analysis and Information Processing》 2024年第1期1-23,共23页
Pneumonia ranks as a leading cause of mortality, particularly in children aged five and under. Detecting this disease typically requires radiologists to examine chest X-rays and report their findings to physicians, a ... Pneumonia ranks as a leading cause of mortality, particularly in children aged five and under. Detecting this disease typically requires radiologists to examine chest X-rays and report their findings to physicians, a task susceptible to human error. The application of Deep Transfer Learning (DTL) for the identification of pneumonia through chest X-rays is hindered by a shortage of available images, which has led to less than optimal DTL performance and issues with overfitting. Overfitting is characterized by a model’s learning that is too closely fitted to the training data, reducing its effectiveness on unseen data. The problem of overfitting is especially prevalent in medical image processing due to the high costs and extensive time required for image annotation, as well as the challenge of collecting substantial datasets that also respect patient privacy concerning infectious diseases such as pneumonia. To mitigate these challenges, this paper introduces the use of conditional generative adversarial networks (CGAN) to enrich the pneumonia dataset with 2690 synthesized X-ray images of the minority class, aiming to even out the dataset distribution for improved diagnostic performance. Subsequently, we applied four modified lightweight deep transfer learning models such as Xception, MobileNetV2, MobileNet, and EfficientNetB0. These models have been fine-tuned and evaluated, demonstrating remarkable detection accuracies of 99.26%, 98.23%, 97.06%, and 94.55%, respectively, across fifty epochs. The experimental results validate that the models we have proposed achieve high detection accuracy rates, with the best model reaching up to 99.26% effectiveness, outperforming other models in the diagnosis of pneumonia from X-ray images. 展开更多
关键词 Pneumonia Detection Pediatric Radiology CGAN (Conditional Generative Adversarial networks) Deep transfer Learning Medical Image Analysis
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Spatial patterns nitrogen transfer models of ectomycorrhizal networks in a Mongolian scotch pine plantation
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作者 Yanbin Liu Hongmei Chen Pu Mou 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期337-344,共8页
Ectomycorrhizal(EM)networks provide a variety of services to plants and ecosystems include nutrient uptake and transfer,seedling survival,internal cycling of nutrients,plant competition,and so on.To deeply their struc... Ectomycorrhizal(EM)networks provide a variety of services to plants and ecosystems include nutrient uptake and transfer,seedling survival,internal cycling of nutrients,plant competition,and so on.To deeply their structure and function in ecosystems,we investigated the spatial patterns and nitrogen(N)transfer of EM networks usingN labelling technique in a Mongolian scotch pine(Pinus sylvestris var.mongolica Litv.)plantation in Northeastern China.In August 2011,four plots(20 × 20 m)were set up in the plantation.125 ml 5 at.%0.15 mol/LNHNOsolution was injected into soil at the center of each plot.Before and 2,6,30 and 215 days after theN application,needles(current year)of each pine were sampled along four 12 m sampling lines.Needle total N andN concentrations were analyzed.We observed needle N andN concentrations increased significantly over time afterN application,up to 31 and0.42%,respectively.There was no correlation between needle N concentration andN/N ratio(R2=0.40,n=5,P=0.156),while excess needle N concentration and excess needleN/N ratio were positively correlated across different time intervals(R~2=0.89,n=4,P\0.05),but deceased with time interval lengthening.NeedleN/N ratio increased with time,but it was not correlated with distance.NeedleN/N ratio was negative with distance before and 6th day and 30th day,positive with distance at 2nd day,but the trend was considerably weaker,their slop were close to zero.These results demonstrated that EM networks were ubiquitous and uniformly distributed in the Mongolian scotch pine plantation and a random network.We found N transfer efficiency was very high,absorbed N by EM network was transferred as wide as possible,we observed N uptake of plant had strong bias forN andN,namely N fractionation.Understanding the structure and function of EM networks in ecosystems may lead to a deeper understanding of ecological stability and evolution,and thus provide new theoretical approaches to improve conservation practices for the management of the Earth’s ecosystems. 展开更多
关键词 Ectomycorrhizal networks Spatial patterns Nitrogen transfer Mongolian scotch pine plantation Stable isotope 15N labelling
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基于回声状态网络的智能合约漏洞检测方法 被引量:1
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作者 刘春霞 徐晗颖 +2 位作者 高改梅 党伟超 李子路 《计算机应用》 北大核心 2025年第1期153-161,共9页
区块链平台上的智能合约是为链上各方提供安全可信赖服务的去中心化应用程序,而智能合约漏洞检测能确保智能合约的安全性。然而,现有的智能合约漏洞检测方法在样本数量不均衡和语义信息挖掘不全面时,会出现特征学习不足和漏洞检测准确... 区块链平台上的智能合约是为链上各方提供安全可信赖服务的去中心化应用程序,而智能合约漏洞检测能确保智能合约的安全性。然而,现有的智能合约漏洞检测方法在样本数量不均衡和语义信息挖掘不全面时,会出现特征学习不足和漏洞检测准确率低的问题,而且,这些方法无法对新的合约漏洞进行检测。针对上述问题,提出一种基于回声状态网络(ESN)的智能合约漏洞检测方法。首先,根据合约图,对不同语义、语法边进行学习,并利用Skip-Gram模型训练得到特征向量;其次,结合ESN和迁移学习,实现对新合约漏洞的迁移扩展,以提高漏洞检测率;最后,在Etherscan平台搜集的智能合约数据集上进行实验。实验结果表明,所提方法的准确率、精确率、召回率和F1分数分别达到了94.30%、97.54%、91.68%和94.52%,与双向长短时记忆(BLSTM)网络、自注意力机制的双向长短时记忆(BLSTM-ATT)相比,所提方法的准确率分别提高了5.93和11.75个百分点,漏洞检测性能更优。消融实验也进一步验证了ESN对智能合约漏洞检测的有效性。 展开更多
关键词 漏洞检测 智能合约 回声状态网络 迁移学习 区块链
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融合时频图与分布适应的轴承故障诊断方法 被引量:2
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作者 许志恒 葛鲲鹏 《机械设计与制造》 北大核心 2025年第4期51-59,共9页
针对实际工业场景下轴承故障诊断仍面临的缺少足量故障样本和变工况导致数据分布差异,提出一种融合时频图与分布适应的轴承故障诊断方法。首先,采用连续小波变换处理原始振动信号并提取时频图;其次,构建卷积神经网络实现深度特征自适应... 针对实际工业场景下轴承故障诊断仍面临的缺少足量故障样本和变工况导致数据分布差异,提出一种融合时频图与分布适应的轴承故障诊断方法。首先,采用连续小波变换处理原始振动信号并提取时频图;其次,构建卷积神经网络实现深度特征自适应提取;其次,提出一种改进平衡分布对齐的域适应方法,通过融合最大边际准则实现缩小不同域间分布差异过程中提高特征数据可分性,并基于源域特征数据训练获得自适应分类器,实现不同工况下的轴承故障识别与分类;最后,为验证所提出方法的有效性与泛化能力,采用两种轴承故障数据集开展平衡与非平衡数据样本下的跨域故障诊断实验分析,实验结果表明所提出方法在两种数据集上的平均故障诊断准确率最高分别可达100%和97.50%,明显优于基于经典迁移学习方法构建的对比模型。 展开更多
关键词 故障诊断 振动信号 时频图 卷积神经网络 迁移学习
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Mid-Range Wireless Power Transfer and Its Application to Body Sensor Networks 被引量:5
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作者 Fei Zhang Jianbo Liu +1 位作者 Zhihong Mao Mingui Sun 《Open Journal of Applied Sciences》 2012年第1期35-46,共12页
It has been reported that, through the evanescent near fields, the strongly coupled magnetic resonance is able to achieve an efficient mid-range Wireless Power Transfer (WPT) beyond the characteristic size of the reso... It has been reported that, through the evanescent near fields, the strongly coupled magnetic resonance is able to achieve an efficient mid-range Wireless Power Transfer (WPT) beyond the characteristic size of the resonator. Recent studies on of the relay effect of the WPT allow more distant and flexible energy transmission. These new developments hold a promise to construct a fully wireless Body Sensor Network (wBSN) using the new mid-range WPT theory. In this paper, a general optimization strategy for a WPT network is presented by analysis and simulation using the coupled mode theory. Based on the results of theoretical and computational study, two types of thin-film resonators are designed and prototyped for the construction of wBSNs. These resonators and associated electronic components can be integrated into a WPT platform to permit wireless power delivery to multiple wearable sensors and medical implants on the surface and within the human body. Our experiments have demonstrated the feasibility of the WPT approach. 展开更多
关键词 BODY Sensor network STRONGLY COUPLED Magnetic RESONANCE Wireless Power transfer COUPLED Mode Theory RELAY Effect
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基于改进随机配置网络的工业软测量建模实验
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作者 邓晓刚 张静 王平 《实验室研究与探索》 北大核心 2025年第5期32-36,53,共6页
针对传统随机配置网络方法在变工况工业场景下难以建立准确软测量模型的问题,提出一种改进的随机配置网络(SCN)软测量建模方法,即多源迁移随机配置网络。以典型工业装置连续搅拌反应釜为例,通过实验研究验证了该方法的有效性。该方法将... 针对传统随机配置网络方法在变工况工业场景下难以建立准确软测量模型的问题,提出一种改进的随机配置网络(SCN)软测量建模方法,即多源迁移随机配置网络。以典型工业装置连续搅拌反应釜为例,通过实验研究验证了该方法的有效性。该方法将历史工况数据作为源域,将新工况数据作为目标域,采用K-means聚类算法将源域划分为多个子源域。针对每个子源域与目标域,分别建立SCN模型,并引入最大均值差异准则对多个迁移SCN模型进行加权集成。实验结果表明,所提出的多源迁移随机配置网络模型能够准确预测目标域的新样本,其建模性能优于传统的SCN模型。 展开更多
关键词 软测量 随机配置网络 迁移学习 多源域 最大均值差异
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基于复杂网络的城市轨道交通网络韧性分析
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作者 杨向飞 童冬冬 张静芳 《中国铁路》 北大核心 2025年第11期141-150,共10页
为分析城市轨道交通网络应对不同攻击时的韧性特征,基于复杂网络和韧性理论,构建定量网络结构韧性评估模型。模型包括初始、攻击和恢复3个阶段,采用点度值、聚类系数、中心性以及随机排序4种不同的攻击和恢复模式,以网络密度、网络效率... 为分析城市轨道交通网络应对不同攻击时的韧性特征,基于复杂网络和韧性理论,构建定量网络结构韧性评估模型。模型包括初始、攻击和恢复3个阶段,采用点度值、聚类系数、中心性以及随机排序4种不同的攻击和恢复模式,以网络密度、网络效率及网络连通率3个特征作为衡量城市轨道交通网络韧性的关键指标,通过空间向量计算网络结构韧性值。以北京市城市轨道交通为例,运用Space-L和Space-C模型构建线路网络与换乘网络,分析4种攻击和恢复模式下网络韧性指标变化情况。研究表明,线路网络规模大于换乘网络规模,但其网络密度和效率均极低。同时,2种网络在经受DA模式攻击下,网络各项指标下降最快;在ZR模式下,网络各项指标恢复最快;在ZADR模式下2个网络同时具有最高韧性水平,韧性值分别为0.21244和0.52209。建议北京市轨道交通应重点加强站点、线路之间的衔接性,对中心性和点度值较高的站点和线路进行保护,以提高整体网络的韧性水平。 展开更多
关键词 城市交通 复杂网络 韧性评估 线路网络 换乘网络
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Pattern recognition and data mining software based on artificial neural networks applied to proton transfer in aqueous environments 被引量:2
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作者 Amani Tahat Jordi Marti +1 位作者 Ali Khwaldeh Kaher Tahat 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期410-421,共12页
In computational physics proton transfer phenomena could be viewed as pattern classification problems based on a set of input features allowing classification of the proton motion into two categories: transfer 'occu... In computational physics proton transfer phenomena could be viewed as pattern classification problems based on a set of input features allowing classification of the proton motion into two categories: transfer 'occurred' and transfer 'not occurred'. The goal of this paper is to evaluate the use of artificial neural networks in the classification of proton transfer events, based on the feed-forward back propagation neural network, used as a classifier to distinguish between the two transfer cases. In this paper, we use a new developed data mining and pattern recognition tool for automating, controlling, and drawing charts of the output data of an Empirical Valence Bond existing code. The study analyzes the need for pattern recognition in aqueous proton transfer processes and how the learning approach in error back propagation (multilayer perceptron algorithms) could be satisfactorily employed in the present case. We present a tool for pattern recognition and validate the code including a real physical case study. The results of applying the artificial neural networks methodology to crowd patterns based upon selected physical properties (e.g., temperature, density) show the abilities of the network to learn proton transfer patterns corresponding to properties of the aqueous environments, which is in turn proved to be fully compatible with previous proton transfer studies. 展开更多
关键词 pattern recognition proton transfer chart pattern data mining artificial neural network empiricalvalence bond
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Forecasting Loss of Ecosystem Service Value Using a BP Network: A Case Study of the Impact of the South-to-north Water Transfer Project on the Ecological Environmental in Xiangfan, Hubei Province, China 被引量:1
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作者 YUN-FENG CHEN, JING-XUAN ZHOU, JIE XIAO, AND YAN-PING LIEnvironmental Science and Engineering College, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第4期379-391,共13页
Objective To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific... Objective To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific countermeasures. Methods A three-layer BP network was built to simulate topology and process of the eco-economy system of Xiangfan. Historical data of ecological environmental factors and socio-economic factors as inputs, and corresponding historical data of ecosystem service value (ESV) and GDP as target outputs, were presented to train and test the network. When predicted input data after 2001 were presented to trained network as generalization sets, ESVs and GDPs of 2002, 2003, 2004... till 2050 were simulated as output in succession. Results Up to 2050, the area would have suffered an accumulative total ESV loss of RMB 104.9 billion, which accounted for 37.36% of the present ESV. The coinstantaneous GDP would change asynchronously with ESV, it would go through an up-to-down process and finally lose RMB89.3 billion, which accounted for 18.71% of 2001. Conclusions The simulation indicates that ESV loss means damage to the capability of socio-economic sustainable development, and suggests that artificial neural networks (ANNs) provide a feasible and effective method and have an important potential in ESV modeling. 展开更多
关键词 Artificial neural network BP Ecosystem service value South-to-north Water transfer Project
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基于ADS-B多特征迁移学习的GNSS干扰检测方法
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作者 陈敏 李昊宇 +1 位作者 何炜琨 吴仁彪 《信号处理》 北大核心 2025年第7期1241-1254,共14页
全球导航卫星系统(Global Navigation Satellite System,GNSS)是现代航空系统的重要基础,其极易受到射频干扰,这可能导致航班备降、复飞或进近中止等情形,对航空安全造成严重影响。广播式自动相关监视(Automatic Dependent Surveillance... 全球导航卫星系统(Global Navigation Satellite System,GNSS)是现代航空系统的重要基础,其极易受到射频干扰,这可能导致航班备降、复飞或进近中止等情形,对航空安全造成严重影响。广播式自动相关监视(Automatic Dependent Surveillance-Broadcast,ADS-B)依赖于GNSS获取飞机位置信息,当GNSS受到射频干扰时,ADS-B的可用性也会受到影响。基于ADS-B数据来进行GNSS干扰检测成为一种可行的解决方案。针对现有基于ADS-B数据的GNSS干扰检测模型存在无法兼容多个ADS-B版本,难以适应我国国情的问题,以GNSS干扰事件中的ADS-B数据为研究对象,分析其在干扰条件下的特点,包括航迹波动和导航质量指标的变化特性。引入滑动窗口技术,动态计算统计特征并扩展特征维度,以更全面准确地反映干扰影响;提出了一种结合长短期记忆网络自编码器(Long Short-Term Memory-AutoEncoder,LSTM-AE)与领域对抗神经网络(Domain Adversarial Neural Network,DANN)的GNSS干扰检测方法。该方法通过LSTM-AE提取不同版本ADS-B的特征,并将其映射到同一个特征空间,提供一致的特征表示;采用DANN网络实现对DO-260A/B版本ADS-B数据(源域)中GNSS干扰的检测,并借助DANN的迁移学习能力,使其适应于DO-260版本的ADS-B数据(目标域),从而实现跨版本的高效检测。实验结果表明,所提出的LSTM-AE-DANN模型在DO-260、DO-260A/B版本的ADS-B数据集上均表现出优秀的检测性能和更强的适用性,适合我国国情,具有显著的实用价值。 展开更多
关键词 全球导航卫星系统干扰检测 广播式自动相关监视 长短期记忆自编码器 领域对抗神经网络 迁移学习 航空安全
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