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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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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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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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Topology-driven energy transfer networks for upconversion stimulated emission depletion microscopy
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作者 Weizhao Gu Simone Lamon +2 位作者 Haoyi Yu Qiming Zhang Min Gu 《Light: Science & Applications》 2025年第12期4176-4191,共16页
Lanthanide-doped upconversion nanoparticles enable upconversion stimulated emission depletion microscopy with high photostability and low-intensity near-infrared continuous-wave lasers.Controlling energy transfer dyna... Lanthanide-doped upconversion nanoparticles enable upconversion stimulated emission depletion microscopy with high photostability and low-intensity near-infrared continuous-wave lasers.Controlling energy transfer dynamics in these nanoparticles is crucial for super-resolution microscopy with minimal laser intensities and high photon budgets.However,traditional methods neglect the spatial distribution of lanthanide ions and its effect on energy transfer dynamics.Here,we introduce topology-driven energy transfer networks in lanthanide-doped upconversion nanoparticles for upconversion stimulated emission depletion microscopy with reduced laser intensities,maintaining a high photon budget.Spatial separation of Yb^(3+)sensitizers and Tm^(3+)emitters in 50-nm core-shell nanoparticles enhance energy transfer dynamics for super-resolution microscopy.Topology-dependent energy migration produces strong 450-nm upconversion luminescence under low-power 980-nm excitation.Enhanced cross-relaxation improves optical switching efficiency,achieving a saturation intensity of 0.06 MW cm^(−2) under excitation at 980 nm and depletion at 808 nm.Super-resolution imaging with a 65-nm lateral resolution is achieved using intensities of 0.03 MW cm^(−2) for a Gaussian-shaped excitation laser at 980 nm and 1 MW cm^(−2) for a donut-shaped depletion laser at 808 nm,representing a 10-fold reduction in excitation intensity and a 3-fold reduction in depletion intensity compared to conventional methods.These findings demonstrate the potential of harnessing topology-dependent energy transfer dynamics in upconversion nanoparticles for advancing low-power super-resolution applications. 展开更多
关键词 photostability lanthanide doped upconversion nanoparticles topology driven energy transfer networks lanthanide ions upconversion stimulated emission depletion microscopy near infrared continuous wave lasers energy transfer dynamics super resolution microscopy
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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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Deep transfer network of heterogeneous domain feature in machine translation
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作者 Yupeng Liu Yanan Zhang Xiaochen Zhang 《High-Confidence Computing》 2022年第4期8-13,共6页
In order to address the shortcoming of feature representation limitation in machine translation(MT)system,this paper presents a feature transfer method in MT.Meta feature transfer of the decoding process considered no... In order to address the shortcoming of feature representation limitation in machine translation(MT)system,this paper presents a feature transfer method in MT.Meta feature transfer of the decoding process considered not only their own translation system,but also transferred knowledge of another translation system.The domain meta feature and the objective function of domain adaptation are used to better model the domain transfer task.In this paper,extensive experiments and comparisons are made.The experiment results show that the proposed model has a significant improvement in domain transfer task.The first model has better performance than baseline system,which improves 3.06 BLEU score on the news test set,improves 3.27 BLEU score on the education test set,and improves 3.93 BLEU score on the law test set;The second model improves 3.16 BLEU score on the news test set,improves 3.54 BLEU score on the education test set,and improves 4.2 BLEU score on the law test set. 展开更多
关键词 Neural translation model Deep transfer network Heterogeneous domain Meta feature
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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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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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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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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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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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Land-Use Classification via Transfer Learning with a Deep Convolutional Neural Network
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作者 Chu-Yin Weng 《Journal of Intelligent Learning Systems and Applications》 2022年第2期15-23,共9页
Land cover classification provides efficient and accurate information regarding human land-use, which is crucial for monitoring urban development patterns, management of water and other natural resources, and land-use... Land cover classification provides efficient and accurate information regarding human land-use, which is crucial for monitoring urban development patterns, management of water and other natural resources, and land-use planning and regulation. However, land-use classification requires highly trained, complex learning algorithms for accurate classification. Current machine learning techniques already exist to provide accurate image recognition. This research paper develops an image-based land-use classifier using transfer learning with a pre-trained ResNet-18 convolutional neural network. Variations of the resulting approach were compared to show a direct relationship between training dataset size and epoch length to accuracy. Experiment results show that transfer learning is an effective way to create models to classify satellite images of land-use with a predictive performance. This approach would be beneficial to the monitoring and predicting of urban development patterns, management of water and other natural resources, and land-use planning. 展开更多
关键词 Land-Use Classification Machine Learning transfer Learning Convolutional Neural network
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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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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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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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基于半监督和迁移学习算法的气瓶阶段损伤分布预测
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作者 蒋鹏 吴爽 +3 位作者 邵云飞 杨畅 张璐莹 孙博文 《无损检测》 2026年第2期44-51,共8页
目前气瓶损伤分布识别主要采用聚类算法,但聚类的类别数受评判准则的影响较大,无法确认真实的损伤类型分布。因此,提出了一种基于Mean-teacher加迁移学习的半监督算法。首先构建了气瓶分阶段压力损伤试验,对不同通道获得的声发射信号数... 目前气瓶损伤分布识别主要采用聚类算法,但聚类的类别数受评判准则的影响较大,无法确认真实的损伤类型分布。因此,提出了一种基于Mean-teacher加迁移学习的半监督算法。首先构建了气瓶分阶段压力损伤试验,对不同通道获得的声发射信号数据进行了时域、频域特征分析,采用1~7阶段的声发射信号标注数据及未标注数据用于训练,形成数据集,并利用第8阶段的声发射信号标注数据进行测试。试验结果表明,所提出的半监督学习算法,在少量标签数据下仍获得了较高的预测准确率。 展开更多
关键词 玻璃纤维缠绕气瓶 半监督算法 声发射信号 迁移学习 mean-teacher网络结构模型
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一种基于无监督学习的智能并行结构网格生成框架
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作者 陈新海 彭嘉明 +5 位作者 乔鹏 贾孟涵 王庆林 张翔 杨博 刘杰 《计算机研究与发展》 北大核心 2026年第2期434-447,共14页
随着高性能计算技术的迅猛发展,科学计算问题的复杂度和计算规模显著提升。网格生成作为科学计算的前置输入,是高性能计算领域的重要研究方向。针对大规模网格生成计算效率低、人机交互复杂等难题,发展智能化网格方法已成为研究热点,但... 随着高性能计算技术的迅猛发展,科学计算问题的复杂度和计算规模显著提升。网格生成作为科学计算的前置输入,是高性能计算领域的重要研究方向。针对大规模网格生成计算效率低、人机交互复杂等难题,发展智能化网格方法已成为研究热点,但如何在网格领域实现高性能计算与人工智能深度融合仍处于研究空白。针对上述问题,提出了一种基于无监督学习的智能并行结构网格生成框架,支持大规模多块结构网格的高效生成。框架集成了基于标架场的分块方法、傅里叶柯尔莫哥洛夫-阿诺德网络(Fourier Kolmogorov-Arnold network,傅里叶KAN)模型和网格对齐方法,采用无监督学习模式,自适应学习高质量网格划分规则,有效解决了已有智能方法在处理复杂外形上的局限性。引入并行迁移学习机制,通过迁移不同进程间网格生成任务的相似性特征,显著提升了模型收敛效率。实验结果表明,所提出的方法在亿维网格生成任务中,相比传统网格生成实现了最高10倍的效率提升。同时在5个不同质量度量下优于已有智能网格生成方法,达到了最优水平。 展开更多
关键词 高性能计算 无监督学习 并行网格生成 傅里叶KAN 迁移学习
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不同内膜准备方案对子宫内膜异位症患者冻融胚胎移植妊娠结局影响的网状Meta分析
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作者 陶钰 王新 赵瑞华 《生殖医学杂志》 2026年第2期230-241,共12页
目的采用网状Meta分析系统评价冻融胚胎移植(FET)前不同内膜准备方案对子宫内膜异位症(EMs)患者妊娠结局的影响。方法检索中国知网(CNKI)、维普、万方、PubMed、Embase、Web of Science、Cochrane Library等数据库关于EMs患者行FET前采... 目的采用网状Meta分析系统评价冻融胚胎移植(FET)前不同内膜准备方案对子宫内膜异位症(EMs)患者妊娠结局的影响。方法检索中国知网(CNKI)、维普、万方、PubMed、Embase、Web of Science、Cochrane Library等数据库关于EMs患者行FET前采用不同内膜准备方案与妊娠结局关联的研究,检索时间自建库至2025年2月。由2名评价员按Cochrane手册标准独立对文献资料进行提取,应用Jadad量表和纽卡斯尔-渥太华量表分别进行质量评价。采用Stata SE 16.0软件进行一致性检验与网络证据图绘制。结果最终纳入文献41篇,涉及到的内膜准备方案共14种。网状Meta分析结果显示,应用不同内膜准备方案EMs患者FET周期临床妊娠率的高低顺序依次为:提前降调节2个周期以上联合激素替代周期>卵泡期长效降调节联合诱导排卵周期>提前降调节2个周期联合激素替代周期>提前降调节2个周期以上>卵泡期长效降调节联合激素替代周期>提前降调节2个周期>黄体期长效降调节>诱导排卵周期>卵泡期长效降调节>激素替代周期>黄体期短效降调节>自然周期>促性腺激素释放激素拮抗剂>卵泡期短效降调节。结论从EMs患者FET周期的临床妊娠率来看,最优的子宫内膜准备方案是提前降调节2个周期以上联合激素替代周期,其次是卵泡期长效降调节联合诱导排卵周期,再次是提前降调节2个周期联合激素替代周期,而卵泡期短效降调节方案的效果相对较差。 展开更多
关键词 子宫内膜异位症 内膜准备方案 冻融胚胎移植 网状Meta分析
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城市技术转移网络地位、要素流动与企业创新质量
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作者 刘书彤 曹效喜 《云南财经大学学报》 北大核心 2026年第1期93-110,共18页
技术转移网络与企业创新质量是推动经济高质量发展和增强区域创新竞争力的核心要素。运用复杂网络方法构建城市技术转移网络,测度地级市的网络中心性特征,并通过实证分析其对企业创新质量的影响。研究发现,城市技术转移网络中心性的提... 技术转移网络与企业创新质量是推动经济高质量发展和增强区域创新竞争力的核心要素。运用复杂网络方法构建城市技术转移网络,测度地级市的网络中心性特征,并通过实证分析其对企业创新质量的影响。研究发现,城市技术转移网络中心性的提升显著促进企业创新质量,该结论经多种稳健性检验后依然成立。异质性分析表明,该促进效应在不同情境下存在差异:从企业层面看,面临激烈外部竞争且处于稳定环境的企业中效应更为显著;从行业层面看,非高科技行业和制造业的促进效应更加明显;从区域层面看,东部地区和市场化程度较高地区的作用更加突出。机制检验表明,技术转移网络中心地位的提升主要通过要素流动渠道影响创新质量,具体表现为促进劳动力和数据要素流动,同时抑制资本要素流动。而潜在的知识溢出机制的作用相对较小,创新生态系统机制和政策支持机制不显著。拓展性分析表明,知识溢出机制在技术转移网络影响企业创新质量中发挥了补充作用,但作用相对有限;而创新生态系统机制和政策支持机制的传导路径则未通过显著性检验。 展开更多
关键词 技术转移网络 企业创新质量 要素流动 网络中心性 复杂网络
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基于多尺度分层交替迁移学习的小样本轴承跨域故障诊断
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作者 曹景浩 文传博 《轴承》 北大核心 2026年第1期65-74,共10页
针对实际应用中训练样本不足以及跨工况轴承故障诊断中不同工况数据分布差异较大导致无法取得令人满意的诊断结果的问题,提出了一种基于多尺度分层交替迁移学习的小样本轴承跨域故障诊断模型。构造了一个多尺度特征提取器,以减少信息损... 针对实际应用中训练样本不足以及跨工况轴承故障诊断中不同工况数据分布差异较大导致无法取得令人满意的诊断结果的问题,提出了一种基于多尺度分层交替迁移学习的小样本轴承跨域故障诊断模型。构造了一个多尺度特征提取器,以减少信息损失,充分挖掘振动信号中的特征;为了处理域位移问题,提出分层交替迁移学习算法(HATL),分层交替计算Coral和LMMD损失函数,缩小源域与目标域的分布距离。在凯斯西储大学轴承数据集和江南大学轴承数据集上进行了迁移试验,并与一些经典迁移学习模型进行对比,结果表明在小样本训练数据集下,所提模型具有优秀的特征迁移能力。 展开更多
关键词 滚动轴承 故障诊断 小样本 迁移学习 卷积神经网络
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