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Curvularin derivatives from hydrothermal vent sediment fungus Penicillium sp.HL-50 guided by molecular networking and their antiinflammatory activity 被引量:2
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作者 Chunxue Yu Zixuan Xia +6 位作者 Zhipeng Xu Xiyang Tang Wenjuan Ding Jihua Wei Danmei Tian Bin Wu Jinshan Tang 《Chinese Journal of Natural Medicines》 2025年第1期119-128,共10页
Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid ... Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid of curvularin and purine.The structures and absolute configurations of compounds 1-9 were elucidated via nuclear magnetic resonance(NMR)spectroscopy,X-ray diffraction,electronic circular dichroism(ECD)calculations,^(13)C NMR calculation,modified Mosher's method,and chemical derivatization.Investigation of anti-inflammatory activities revealed that compounds 7-9,11,12,14,15,and 18 exhibited significant suppressive effects against lipopolysaccharide(LPS)-induced nitric oxide(NO)production in murine macrophage RAW264.7 cells,with IC_(50)values ranging from 0.44 to 4.40μmol·L^(-1).Furthermore,these bioactive compounds were found to suppress the expression of inflammation-related proteins,including inducible NO synthase(i NOS),cyclooxygenase-2(COX-2),NLR family pyrin domain-containing protein 3(NLRP3),and nuclear factor kappa-B(NF-κB).Additional studies demonstrated that the novel compound 7 possessed potent antiinflammatory activity by inhibiting the transcription of inflammation-related genes,downregulating the expression of inflammation-related proteins,and inhibiting the release of inflammatory cytokines,indicating its potential application in the treatment of inflammatory diseases. 展开更多
关键词 Penicillium sp.HL-50 Curvularin derivatives Molecular networking Anti-inflammatory activity
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Cross-Domain Time Synchronization in Software-Defined Time-Sensitive Networking 被引量:1
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作者 Zhang Xiaodong Shou Guochu +2 位作者 Li Hongxing Liu Yaqiong Hu Yihong 《China Communications》 2025年第9期289-306,共18页
The rise of time-sensitive applications with broad geographical scope drives the development of time-sensitive networking(TSN)from intra-domain to inter-domain to ensure overall end-to-end connectivity requirements in... The rise of time-sensitive applications with broad geographical scope drives the development of time-sensitive networking(TSN)from intra-domain to inter-domain to ensure overall end-to-end connectivity requirements in heterogeneous deployments.When multiple TSN networks interconnect over non-TSN networks,all devices in the network need to be syn-chronized by sharing a uniform time reference.How-ever,most non-TSN networks are best-effort.Path delay asymmetry and random noise accumulation can introduce unpredictable time errors during end-to-end time synchronization.These factors can degrade syn-chronization performance.Therefore,cross-domain time synchronization becomes a challenging issue for multiple TSN networks interconnected by non-TSN networks.This paper presents a cross-domain time synchronization scheme that follows the software-defined TSN(SD-TSN)paradigm.It utilizes a com-bined control plane constructed by a coordinate con-troller and a domain controller for centralized control and management of cross-domain time synchroniza-tion.The general operation flow of the cross-domain time synchronization process is designed.The mecha-nism of cross-domain time synchronization is revealed by introducing a synchronization model and an error compensation method.A TSN cross-domain proto-type testbed is constructed for verification.Results show that the scheme can achieve end-to-end high-precision time synchronization with accuracy and sta-bility. 展开更多
关键词 cross-domain time synchronization de-terministic communications error compensation software-defined networking(SDN) time-sensitive networking(TSN)
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Multi-Band Integrated Networking for Efficient Spectrum Utilization in 6G 被引量:1
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作者 Wang Ailing Kong Lei +4 位作者 Liu Jianjun Xia Liang Wang Xiaoqian Wang Qixing Liu Guangyi 《China Communications》 2025年第4期42-54,共13页
The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic c... The sixth-generation(6G)networks will consist of multiple bands such as low-frequency,midfrequency,millimeter wave,terahertz and other bands to meet various business requirements and networking scenarios.The dynamic complementarity of multiple bands are crucial for enhancing the spectrum efficiency,reducing network energy consumption,and ensuring a consistent user experience.This paper investigates the present researches and challenges associated with deployment of multi-band integrated networks in existing infrastructures.Then,an evolutionary path for integrated networking is proposed with the consideration of maturity of emerging technologies and practical network deployment.The proposed design principles for 6G multi-band integrated networking aim to achieve on-demand networking objectives,while the architecture supports full spectrum access and collaboration between high and low frequencies.In addition,the potential key air interface technologies and intelligent technologies for integrated networking are comprehensively discussed.It will be a crucial basis for the subsequent standards promotion of 6G multi-band integrated networking technology. 展开更多
关键词 full spectrum access high and low frequency collaboration multi-band integrated networking 6G spectrum efficiency
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Call for Papers─Feature Topic Vol.23,No.1,2026 Space-Terrestrial Integrated 6G Network:Architecture,Networking,and Transmission Technologies
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《China Communications》 2025年第6期F0003-F0003,共1页
With the large-scale deployment of satellite constellations such as Starlink and the rapid advancement of technologies including artificial intelligence (AI) and non-terrestrial networks (NTNs), the integration of hig... With the large-scale deployment of satellite constellations such as Starlink and the rapid advancement of technologies including artificial intelligence (AI) and non-terrestrial networks (NTNs), the integration of high, medium, and low Earth orbit satellite networks with terrestrial networks has become a critical direction for future communication technologies. The objective is to develop a space-terrestrial integrated 6G network that ensures ubiquitous connectivity and seamless services, facilitating intelligent interconnection and collaborative symbiosis among humans, machines, and objects. This integration has become a central focus of global technological innovation. 展开更多
关键词 communication technologiesthe space terrestrial integrated G network g network satellite constellations terrestrial networks artificial intelligence ai intelligent int satellite networks
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Theory and Key Technologies in Space Internet Networking
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作者 Jiangzhou Wang Jiandong Li Di Zhou 《Engineering》 2025年第11期1-2,共2页
The rapid evolution of satellite constellation projects(e.g.,SpaceX)and the standardization of 3rd Generation Partnership Project(3GPP)non-terrestrial networks(NTNs)have positioned satellite Internet networking(SIN)as... The rapid evolution of satellite constellation projects(e.g.,SpaceX)and the standardization of 3rd Generation Partnership Project(3GPP)non-terrestrial networks(NTNs)have positioned satellite Internet networking(SIN)as a cornerstone of future communication systems.The demand for ubiquitous connectivity,resilient infrastructures,and intelligent network services has never been greater,driven by applications ranging from global broadband access to emergency response and space-air-ground integration. 展开更多
关键词 emergency response rd generation partnership project gpp non terrestrial communication systemsthe global broadband access intelligent network services satellite internet networking sin satellite constellation projects egspacex space internet networking
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Non-Terrestrial Networking for 6G:Evolution,Opportunities,and Future Directions
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作者 Feng Wang Shengyu Zhang +1 位作者 Huiting Yang Tony Q.S.Quek 《Engineering》 2025年第11期56-68,共13页
From fifth-generation(5G)communication technology onward,non-terrestrial networks(NTNs)have emerged as a key component of future network architectures.Especially through the rise of low-Earth-orbit satellite constella... From fifth-generation(5G)communication technology onward,non-terrestrial networks(NTNs)have emerged as a key component of future network architectures.Especially through the rise of low-Earth-orbit satellite constellations,NTNs enable a space Internet and present a paradigm shift in delivering reliable services to even the most remote regions on Earth.However,the extensive coverage and rapid movement of satellites pose unique challenges in user equipment access and inter-satellite transmission,impacting the quality of service and service continuity.This paper offers an in-depth review of NTN networking technologies in the context of six-generation(6G)mobile networks evolution,focusing on access management,satellite mobility,and hetero-network slicing.Building on this foundation and considering the latest trends in NTN development,we then present innovative perspectives on emerging challenges,including satellite beamforming,handover mechanisms,and service delivery.Lastly,we identify key open research areas and propose future directions to improve NTN performance and accelerate satellite Internet deployment. 展开更多
关键词 Non-terrestrial networks Six-generation mobile networks Satellite networking Access and mobility management Inter-satellite transmission
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End-to-End Deterministic Transmission with Bounded Time Error in Time-Sensitive Networking
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作者 Ma Hao Shou Guochu +3 位作者 Li Hongxing Liu Yaqiong Hu Yihong Chen Li 《China Communications》 2025年第12期30-46,共17页
Time synchronization is a prerequisite for ensuring determinism in time-sensitive networking(TSN).While time synchronization errors cannot be overlooked,pursuing minimal time errors may incur unnecessary costs.Using c... Time synchronization is a prerequisite for ensuring determinism in time-sensitive networking(TSN).While time synchronization errors cannot be overlooked,pursuing minimal time errors may incur unnecessary costs.Using complex network theory,this study proposes a hierarchy for TSN and introduces the concept of bounded time error.A coupling model between traffic scheduling and time synchronization is established,deriving functional relationships among end-to-end delay,delay jitter,gate window,and time error.These relationships illustrate that time errors can trigger jumps in delay and delay jitter.To evaluate different time errors impact on traffic scheduling performance,an end-to-end transmission experiment scheme is designed,along with the construction of a TSN test platform implementing two representative cases.Case A is a closed TSN domain scenario with pure TSN switches emulating closed factory floor network.Case B depicts remote factory interconnection where TSN domains link via non-TSN domains composed of OpenFlow switches.Results from Case A show that delay and delay jitter on a single node are most significantly affected by time errors,up to one gating cycle.End-to-end delay jitter tends to increase with the number of hops.When the ratio of time error bound to window exceeds 10%,the number of schedulable traffic flows decreases rapidly.Case B reveals that when time error is below 1μs,the number of schedulable traffic flows begins to increase significantly,approaching full schedulability at errors below 0.6μs. 展开更多
关键词 bounded time error deterministic communications time synchronization time-sensitive networking traffic scheduling
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Deep Learning-Based Natural Language Processing Model and Optical Character Recognition for Detection of Online Grooming on Social Networking Services
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作者 Sangmin Kim Byeongcheon Lee +2 位作者 Muazzam Maqsood Jihoon Moon Seungmin Rho 《Computer Modeling in Engineering & Sciences》 2025年第5期2079-2108,共30页
The increased accessibility of social networking services(SNSs)has facilitated communication and information sharing among users.However,it has also heightened concerns about digital safety,particularly for children a... The increased accessibility of social networking services(SNSs)has facilitated communication and information sharing among users.However,it has also heightened concerns about digital safety,particularly for children and adolescents who are increasingly exposed to online grooming crimes.Early and accurate identification of grooming conversations is crucial in preventing long-term harm to victims.However,research on grooming detection in South Korea remains limited,as existing models trained primarily on English text and fail to reflect the unique linguistic features of SNS conversations,leading to inaccurate classifications.To address these issues,this study proposes a novel framework that integrates optical character recognition(OCR)technology with KcELECTRA,a deep learning-based natural language processing(NLP)model that shows excellent performance in processing the colloquial Korean language.In the proposed framework,the KcELECTRA model is fine-tuned by an extensive dataset,including Korean social media conversations,Korean ethical verification data from AI-Hub,and Korean hate speech data from Hug-gingFace,to enable more accurate classification of text extracted from social media conversation images.Experimental results show that the proposed framework achieves an accuracy of 0.953,outperforming existing transformer-based models.Furthermore,OCR technology shows high accuracy in extracting text from images,demonstrating that the proposed framework is effective for online grooming detection.The proposed framework is expected to contribute to the more accurate detection of grooming text and the prevention of grooming-related crimes. 展开更多
关键词 Online grooming KcELECTRA natural language processing optical character recognition social networking service text classification
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Cytotoxic anthrone–cyclopentenone heterodimers from the fungus Penicillium sp.guided by molecular networking
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作者 Ruiyun Huo Jiayu Dong +2 位作者 Gaoran Liu Ying Shi Ling Liu 《Chinese Journal of Natural Medicines》 2025年第10期1259-1267,共9页
(±)-Penicithrones A–D(1a/1b–4a/4b),four novel pairs of anthrone–cyclopentenone heterodimers characterized by a distinctive bridged 6/6/6−5 tetracyclic core skeleton,together with three previously identified co... (±)-Penicithrones A–D(1a/1b–4a/4b),four novel pairs of anthrone–cyclopentenone heterodimers characterized by a distinctive bridged 6/6/6−5 tetracyclic core skeleton,together with three previously identified compounds(5–7),were isolated from the crude extract of the mangrove-derived fungus Penicillium sp.,guided by heteronuclear single quantum correlation(HSQC)-based small molecule accurate recognition technology(SMART 2.0)and liquid chromatography-tandem mass spectrometry(LC-MS/MS)-based molecular networking.The structural elucidation of new compounds was accomplished through comprehensive spectroscopic analysis,and their absolute configurations were determined using DP4+^(13)C nuclear magnetic resonance(NMR)calculations and electronic circular dichroism(ECD)calculations.Compounds 1a/1b–4a/4b demonstrated moderate cytotoxicity against three human cancer cell lines HeLa,HCT116 and MCF-7 with half maximal inhibitory concentration(IC50)values ranging from 15.95±1.64 to 28.56±2.59μmol·L–1. 展开更多
关键词 Mangrove-derived fungi Molecular networking HSQC-based SMART Structure elucidation DP4+13C NMR calculation Cytotoxic activity
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A Hierarchical-Based Sequential Caching Scheme in Named Data Networking
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作者 Zhang Junmin Jin Jihuan +3 位作者 Hou Rui Dong Mianxiong Kaoru Ota Zeng Deze 《China Communications》 2025年第5期48-60,共13页
Named data networking(NDNs)is an idealized deployment of information-centric networking(ICN)that has attracted attention from scientists and scholars worldwide.A distributed in-network caching scheme can efficiently r... Named data networking(NDNs)is an idealized deployment of information-centric networking(ICN)that has attracted attention from scientists and scholars worldwide.A distributed in-network caching scheme can efficiently realize load balancing.However,such a ubiquitous caching approach may cause problems including duplicate caching and low data diversity,thus reducing the caching efficiency of NDN routers.To mitigate these caching problems and improve the NDN caching efficiency,in this paper,a hierarchical-based sequential caching(HSC)scheme is proposed.In this scheme,the NDN routers in the data transmission path are divided into various levels and data with different request frequencies are cached in distinct router levels.The aim is to cache data with high request frequencies in the router that is closest to the content requester to increase the response probability of the nearby data,improve the data caching efficiency of named data networks,shorten the response time,and reduce cache redundancy.Simulation results show that this scheme can effectively improve the cache hit rate(CHR)and reduce the average request delay(ARD)and average route hop(ARH). 展开更多
关键词 hierarchical router named data networking sequential caching
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Detecting and Mitigating Distributed Denial of Service Attacks in Software-Defined Networking
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作者 Abdullah M.Alnajim Faisal Mohammed Alotaibi Sheroz Khan 《Computers, Materials & Continua》 2025年第6期4515-4535,共21页
Distributed denial of service(DDoS)attacks are common network attacks that primarily target Internet of Things(IoT)devices.They are critical for emerging wireless services,especially for applications with limited late... Distributed denial of service(DDoS)attacks are common network attacks that primarily target Internet of Things(IoT)devices.They are critical for emerging wireless services,especially for applications with limited latency.DDoS attacks pose significant risks to entrepreneurial businesses,preventing legitimate customers from accessing their websites.These attacks require intelligent analytics before processing service requests.Distributed denial of service(DDoS)attacks exploit vulnerabilities in IoT devices by launchingmulti-point distributed attacks.These attacks generate massive traffic that overwhelms the victim’s network,disrupting normal operations.The consequences of distributed denial of service(DDoS)attacks are typically more severe in software-defined networks(SDNs)than in traditional networks.The centralised architecture of these networks can exacerbate existing vulnerabilities,as these weaknesses may not be effectively addressed in this model.The preliminary objective for detecting and mitigating distributed denial of service(DDoS)attacks in software-defined networks(SDN)is to monitor traffic patterns and identify anomalies that indicate distributed denial of service(DDoS)attacks.It implements measures to counter the effects ofDDoS attacks,and ensure network reliability and availability by leveraging the flexibility and programmability of SDN to adaptively respond to threats.The authors present a mechanism that leverages the OpenFlow and sFlow protocols to counter the threats posed by DDoS attacks.The results indicate that the proposed model effectively mitigates the negative effects of DDoS attacks in an SDN environment. 展开更多
关键词 Software-defined networking(SDN) distributed denial of service(DDoS)attack sampling Flow(sFlow) OpenFlow OpenDaylight controller
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A High Destruction-Resistant Resilient Networking Platform for Air-to-Ground Cooperative Communications
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作者 Dong Ping Ren Jiaxin +3 位作者 Guo Jiannan Zhang Yuzhen Liu Qianwen Amr Tolba 《China Communications》 2025年第4期27-41,共15页
With the continuous advancement of communication and unmanned aerial vehicle(UAV)technologies,the collaborative operations of diverse platforms,including UAVs and ground vehicles,have been significantly promoted.Howev... With the continuous advancement of communication and unmanned aerial vehicle(UAV)technologies,the collaborative operations of diverse platforms,including UAVs and ground vehicles,have been significantly promoted.However,battlefield uncertainties,such as equipment failures and enemy attacks,can impact these collaborative operations'stability and communication efficiency.To this end,we design a highly destruction-resistant air-ground cooperative resilient networking platform that aims to enhance the robustness of network communications by integrating ground vehicle information for UAV network deployment.It then incorporates the concept of virtual guiding force,enabling the UAV swarm to adaptively configure its network layout based on ground vehicle information,thereby improving network destruction resistance.Simulation results demonstrate that the UAV swarm involved in the proposed platform exhibits balanced flight energy consumption and excellent performance in network destruction resistance. 展开更多
关键词 air-to-ground coordination network destruction resistance SpringBoot UAV
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Key technologies for networking in satellite-terrestrial integrated network
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作者 Haijun ZHANG Sichen LU Xiaoqi ZHANG 《Chinese Journal of Aeronautics》 2025年第9期267-270,共4页
1.Introduction As a key development of the next-generation spatial information infrastructure,1the Satellite-Terrestrial Integrated Network(STIN)has become a strategic priority actively pursued by major spacefaring na... 1.Introduction As a key development of the next-generation spatial information infrastructure,1the Satellite-Terrestrial Integrated Network(STIN)has become a strategic priority actively pursued by major spacefaring nations and regions,including the United States,Europe,China,and Russia.Specifically,Space X’s Starlink project has deployed over 6750 satellites,2while One Web has completed its initial phase of satellite constellation deployment with more than 600 satellites. 展开更多
关键词 satellite terrestrial integrated network satellite constellation starlink project next generation spatial information infrastructure Starlink OneWeb STIN
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基于树形决策卷积神经网络的滚动轴承故障分层诊断
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作者 杨旭 吴程飞 +1 位作者 黄健 赵鹰昊 《北京工业大学学报》 北大核心 2026年第1期64-74,共11页
针对传统滚动轴承故障诊断中故障层次信息利用不充分、诊断精度不足的问题,提出一种带有树形决策层的卷积神经网络(convolutional neural network,CNN)方法以实现故障位置与严重程度的逐层诊断。该模型同时具备CNN的特征提取能力和决策... 针对传统滚动轴承故障诊断中故障层次信息利用不充分、诊断精度不足的问题,提出一种带有树形决策层的卷积神经网络(convolutional neural network,CNN)方法以实现故障位置与严重程度的逐层诊断。该模型同时具备CNN的特征提取能力和决策树的层次结构及分层决策特性。首先,采用共享网络层和2个任务特定的分支全连接层分别提取与故障位置和故障严重程度有关的特征;然后,将2个全连接层的分类结果输入到树形决策层,并使用加权层次分类损失调整模型权重参数,从而实现模型对故障层次信息的自学习;最后,应用帕德博恩大学轴承数据集进行算法性能测试。实验结果表明,该模型的平均分类准确率可达99.15%,与领域内其他的诊断模型相比,实现了更准确的故障位置和严重性的分类。 展开更多
关键词 故障诊断 分层诊断 滚动轴承 卷积神经网络(convolutional neural network CNN) 决策树 集成模型
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极端天气下高速公路自洽能源系统应急资源优化调度方案
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作者 李艳波 张云锐 +4 位作者 杨凯 陈楚润 吕浩楠 武奇生 陈俊硕 《西安交通大学学报》 北大核心 2026年第1期190-200,共11页
针对近年来频发的极端天气灾害对高速公路交通及电力网络基础设施造成严重破坏,导致灾后应急资源调度困难的问题,提出了一种考虑交通网(TN)-电力网(PN)耦合网络的高速公路应急资源优化调度方案。分别搭建TN和PN模型以及TN-PN耦合网络模... 针对近年来频发的极端天气灾害对高速公路交通及电力网络基础设施造成严重破坏,导致灾后应急资源调度困难的问题,提出了一种考虑交通网(TN)-电力网(PN)耦合网络的高速公路应急资源优化调度方案。分别搭建TN和PN模型以及TN-PN耦合网络模型;结合历史气象数据构建极端天气模型并利用蒙特卡罗模拟抽样方法模拟故障场景,得到极端天气运行情况以及线路故障率曲线;利用Dijkstra算法分析应急资源移动路径并构建其调度模型,求出灾后最优调度路线;结合河南某高速公路自洽能源系统的相关数据进行灾后应急资源调度仿真。结果表明:所提优化调度方案比目前常用的两种方案能够提前1~2 h完成故障线路维修,故障负荷的平均负荷恢复量提高了5.95%和2.27%,恢复至正常运行状态所需时间缩短了31.38%和16.28%,可进一步提高应急资源调度效率和高速公路自洽能源系统弹性。 展开更多
关键词 自洽能源系统 极端天气 交通网-电力网耦合网络 应急资源调度
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基于多道卡尔曼滤波神经网络的无监督微地震去噪方法
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作者 张岩 张永雪 +4 位作者 魏子心 董宏丽 韩非 张林军 汪靖哲 《地球物理学报》 北大核心 2026年第1期353-365,共13页
微地震数据中有效信号的振幅、频率,及噪声具有显著的时变特征,当前微地震去噪方法中基于卡尔曼滤波方法高度依赖经验调参而影响应用效率,深度学习方法往往需要大量有效样本监督学习.针对以上问题,提出一种结合卡尔曼滤波与循环神经网... 微地震数据中有效信号的振幅、频率,及噪声具有显著的时变特征,当前微地震去噪方法中基于卡尔曼滤波方法高度依赖经验调参而影响应用效率,深度学习方法往往需要大量有效样本监督学习.针对以上问题,提出一种结合卡尔曼滤波与循环神经网络的无监督微地震数据去噪方法.首先,建立多道微地震数据的卡尔曼滤波状态预测与更新方程,充分利用多道相关性提高卡尔曼滤波参数的表征能力;其次,设计多道卡尔曼滤波状态预测与更新的RNN运算算子,通过链式梯度自动求取方式优化卡尔曼滤波的参数,构建基于循环神经网络模式的多道卡尔曼网络去噪;再次,结合无监督的微地震去噪训练方法,实现卡尔曼参数自动优化,避免有效数据标签的过度依赖;最后,通过理论正演与实际微地震数据的实验结果表明,本文方法在微地震去噪准确性与效率上优于传统卡尔曼滤波与变分自编码器等同类方法. 展开更多
关键词 微地震数据处理 卡尔曼滤波 循环神经网络 噪声压制 无监督网络
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基于轻量化SuperPoint网络的水下光学图像特征提取
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作者 刘艳 朱昌盛 +1 位作者 余彬 霍冠英 《河海大学学报(自然科学版)》 北大核心 2026年第1期167-176,共10页
针对水下光学图像质量下降导致的图像配准、三维重建等水下视觉任务中特征提取鲁棒性差的问题,提出了一种轻量化SuperPoint网络,该网络针对水下光学图像普遍存在颜色失真、模糊等细节退化问题,利用注意力机制,构建频域-空间域动态注意... 针对水下光学图像质量下降导致的图像配准、三维重建等水下视觉任务中特征提取鲁棒性差的问题,提出了一种轻量化SuperPoint网络,该网络针对水下光学图像普遍存在颜色失真、模糊等细节退化问题,利用注意力机制,构建频域-空间域动态注意力融合模块,融合频域与空间域的特征信息,提升网络在水下退化图像中的特征提取能力;构建残差特征增强深度可分离卷积模块,以降低模型复杂度并增强网络的特征提取能力。验证结果表明:该网络较SuperPoint网络参数量减少了13.8%,计算量降低了8.0%,帧率提升31.7%,光照变化和视角变化下的重复率分别提高了2.3%和2.1%,在SQUID和FLSea数据集上的特征点检测与匹配性能评估中具有较好的特征提取鲁棒性。 展开更多
关键词 水下光学图像 SuperPoint网络 轻量化网络 特征提取 特征融合
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基于Space P和K-means的货运航司航线网络特征分析研究
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作者 罗凤娥 卫昌波 +1 位作者 韩晓彤 郭玲玉 《现代电子技术》 北大核心 2026年第1期102-107,共6页
针对航空货运行业的迅速扩张,航空货运网络结构变得更加复杂,文中通过Space P建模方法构建了货运航空公司航线网络模型,并运用K-means聚类算法对网络进行了深入分析。选取度、平均路径长度、聚类系数和中间度等关键网络特性指标对航线... 针对航空货运行业的迅速扩张,航空货运网络结构变得更加复杂,文中通过Space P建模方法构建了货运航空公司航线网络模型,并运用K-means聚类算法对网络进行了深入分析。选取度、平均路径长度、聚类系数和中间度等关键网络特性指标对航线网络进行层次化分类,揭示了网络的复杂特征和层次结构。通过仿真实验评估了网络的小世界特性,并利用轮廓系数得到不同K值下的聚类结果,进而确定最优聚类结果。同时,模拟了航线网络在遭受攻击时的鲁棒性,实验结果表明:在航线网络较为脆弱的情况下,该方法为货运航司航线网络的优化和抗风险能力的提升提供了重要参考。 展开更多
关键词 航空货运 Space P 航线网络 复杂网络 聚类算法 网络特征
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胰高血糖素样肽1受体激动剂替西帕肽治疗阿尔茨海默病的潜在靶点
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作者 张晓敏 杜朋洋 +1 位作者 张秀萍 薛国芳 《中国组织工程研究》 北大核心 2026年第23期6122-6133,共12页
背景:胰高血糖素样肽1受体激动剂作为神经退行性疾病治疗的新型候选药物,已在阿尔茨海默病临床研究中取得突破性进展,其中索马鲁肽等药物已推进至Ⅲ期临床试验阶段。然而,目前对于该类药物神经保护效应的分子作用机制仍存在显著的知识... 背景:胰高血糖素样肽1受体激动剂作为神经退行性疾病治疗的新型候选药物,已在阿尔茨海默病临床研究中取得突破性进展,其中索马鲁肽等药物已推进至Ⅲ期临床试验阶段。然而,目前对于该类药物神经保护效应的分子作用机制仍存在显著的知识缺口。目的:创新性地整合多组学分析技术与网络药理学方法,系统解析阿尔茨海默病病理相关基因谱系与替西帕肽潜在作用靶点的交集网络,鉴定关键调控基因,并通过体内外实验验证其分子机制。方法:采用多维度研究策略:①基于DisGeNET数据库(整合了多种疾病相关的基因组学数据库)构建阿尔茨海默病差异表达基因谱。②通过PubChem数据库(小分子生物活性数据库)获取替西帕肽结构并筛选潜在靶点。③应用DAVID数据库开展GO功能注释及KEGG通路富集分析。④结合STRING数据库与Cytoscape 3.9.1构建蛋白质互作网络,经拓扑网络分析筛选关键基因。⑤细胞水平验证:将HT22细胞分为对照组、模型组(β-淀粉样蛋白1-42寡聚体处理36 h建立HT22细胞阿尔茨海默病体外模型)、给药组(先以β-淀粉样蛋白1-42寡聚体预处理24 h,再加入替西帕肽共处理12 h),通过Western blot分析血管紧张素Ⅱ2型受体蛋白表达,ELISA检测突触蛋白1、突触后致密物质95等突触功能标志物表达水平。⑥动物实验验证:实验分为3组,对照组为WT型C57BL/6小鼠,腹腔注射生理盐水;模型组为3xTg小鼠(拟阿尔茨海默症小鼠),腹腔注射生理盐水;给药组为3xTg小鼠,腹腔注射20 nmol/L替西帕肽;均为隔日1次,共给药15次。使用水迷宫技术分析阿尔茨海默病模型小鼠的认知行为学改善;使用Western blot定量分析β-淀粉样蛋白(6E10)、磷酸化的Tau蛋白(P-tau-181)的表达情况。结果与结论:①从DisGeNET数据库筛选出阿尔茨海默病相关联的基因,共得到3397个关联基因;根据蛋白关联度筛选出了10个连接度最高的关键基因:AGTR2、NTSR1、NTSR2、GHSR、C5AR1、C3AR1、OPRM1、SSTR2、OPRD1、STAT3;GO富集分析和KEGG通路分析,提示替西帕肽可能通过改善神经受体-配体功能来改善阿尔茨海默病。②细胞实验提示,替西帕肽可能通过改善阿尔茨海默病的突触功能来发挥治疗作用,血管紧张素Ⅱ2型受体可能是替西帕肽治疗阿尔茨海默病的潜在靶点。③动物实验提示,替西帕肽能够改善3xTg小鼠的认知能力,改善3xTg小鼠模型脑内的异常β-淀粉样蛋白沉积和Tau蛋白磷酸化。④结论:揭示血管紧张素Ⅱ2型受体是替西帕肽作用于阿尔茨海默病病理进程的关键分子靶点,替西帕肽可能通过调控血管紧张素Ⅱ2型受体介导的突触功能改善来治疗阿尔茨海默病。 展开更多
关键词 替西帕肽 阿尔茨海默病 网络药理学 血管紧张素Ⅱ2型受体 蛋白互作网络 突触功能
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融合注意力增强CNN与Transformer的电网关键节点识别
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作者 黎海涛 乔禄 +2 位作者 杨艳红 谢冬雪 高文浩 《北京工业大学学报》 北大核心 2026年第2期117-129,共13页
为了精确识别电网关键节点以保障电力系统的可靠运行,提出一种基于融合拓扑特征与电气特征的双重自注意力卷积神经网络(convolutional neural network,CNN)的电网关键节点识别方法。首先,构建包含节点的局部拓扑特征、半局部拓扑特征、... 为了精确识别电网关键节点以保障电力系统的可靠运行,提出一种基于融合拓扑特征与电气特征的双重自注意力卷积神经网络(convolutional neural network,CNN)的电网关键节点识别方法。首先,构建包含节点的局部拓扑特征、半局部拓扑特征、电气距离及节点电压的多维特征集;然后,利用压缩-激励(squeeze-and-excitation,SE)自注意力机制改进CNN以增强对节点特征的提取能力,并引入多头自注意力的Transformer编码器以实现拓扑特征与电气特征的深度融合。结果表明:在IEEE 30节点和IEEE 118节点的标准测试系统上,该方法识别关键节点的准确性更高,并且在节点影响力评估和网络鲁棒性方面,得到的电网关键节点对网络的影响更大,鲁棒性更好,为电网的安全稳定运行提供了有效的决策支持。 展开更多
关键词 复杂网络 电网 关键节点识别 卷积神经网络(convolutional neural network CNN) 注意力 特征融合
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