期刊文献+
共找到6,868篇文章
< 1 2 250 >
每页显示 20 50 100
IMPLEMENTING SECURITY FOR ACTIVE NETWORKS IN INTERNET
1
作者 Tang Yin Wang Weiran (College of Electronic Engineering, UEST of China, Chengdu 610054) 《Journal of Electronics(China)》 2003年第4期305-308,共4页
Active networks is primarily a Defense Advanced Research Projects Agency(DARPA)-funded project focusing on the research of mechanisms, applications, and operating systems to develop a reconfigurable network infrastruc... Active networks is primarily a Defense Advanced Research Projects Agency(DARPA)-funded project focusing on the research of mechanisms, applications, and operating systems to develop a reconfigurable network infrastructure. This letter proposes an Secure Active Tracing System (SATS) to implementing security for active networking in Internet. Unlike currently existing schemes, SATS reduces the computational overloads by executing the filtering operation on selected packet streams only when needed. 展开更多
关键词 active networks SECURITY Distributed Denial of Service (DDoS) active network Backbone(ABone) active network Transport System(ANTS) active Signaling Protocol (ASP)
下载PDF
Multi-Path Routing and Resource Allocation in Active Network 被引量:2
2
作者 XUWu-ping YANPu-liu WUMing 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第2期398-404,共7页
An algorithm of traffic distribution called active multi-path routing (AMR)in active network is proposed. AMR adopts multi-path routing and applies nonlinear optimizeapproximate method to distribute network traffic am... An algorithm of traffic distribution called active multi-path routing (AMR)in active network is proposed. AMR adopts multi-path routing and applies nonlinear optimizeapproximate method to distribute network traffic among multiple paths. It is combined to bandwidthresource allocation and the congestion restraint mechanism to avoid congestion happening and worsen.So network performance can be improved greatly. The frame of AMR includes adaptive trafficallocation model, the conception of supply bandwidth and its' allocation model, the principle ofcongestion restraint and its' model, and the implement of AMR based on multi-agents system in activenetwork. Through simulations, AMR has distinct effects on network performance. The results show AMRisa valid traffic regulation algorithm. 展开更多
关键词 multi-path routing resource allocation congestion control active network multi-agent system
下载PDF
Active Network研究综述 被引量:1
3
作者 夏正友 钟亦平 张世永 《小型微型计算机系统》 CSCD 北大核心 2003年第10期1821-1824,共4页
介绍了两种实现 Active Network方法 ,描述 Active Network结构与组成、Active Network封装协议和 ActiveNetwork编程模型 .讨论国内外对 Active Network的研究成果和进展 .在该文最后对 Active network研究作了总结 。
关键词 active-network 离散方法 集成方法 综述 封装协议 编程模型
下载PDF
GPS Rapid Static and Kinematic Positioning Based on GPS Active Network
4
作者 CHEN Wu HU Congwei CHEN Yongqi DING Xiaoli Simon Chi_wo Kowk 《Geo-Spatial Information Science》 2003年第1期5-11,共7页
This paper presents a data processing strategy for GPS kinematic positioning by using a GPS active network to model the GPS errors in double difference observable.Firstly,the double difference residuals are estimated ... This paper presents a data processing strategy for GPS kinematic positioning by using a GPS active network to model the GPS errors in double difference observable.Firstly,the double difference residuals are estimated between the reference stations in the active network.Then the errors at a user station are predicted as the network corrections to user measurements,based on the location of the user.Finally conventional kinematic positioning algorithms can be applied to determine the position of the user station.As an example,continuous 24_hour GPS data in March 2001 has been processed by this method.It clearly demonstrates that,after applying these corrections to a user within the network,both the success rate for ambiguity resolution and the positioning accuracy have been significantly improved. 展开更多
关键词 GPS AMBIGUITY active network network correction kinematic positioning
下载PDF
A Cluster-Based Secure Active Network Environment
5
作者 CHENXiao-lin ZHOUJing-yang +2 位作者 DAIHan LUSang-lu CHENGui-hai 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期142-146,共5页
We introduce a cluster-based secure active network environment (CSANE) which separates the processing of IP packets from that of active packets in active routers. In this environment, the active code authorized or tru... We introduce a cluster-based secure active network environment (CSANE) which separates the processing of IP packets from that of active packets in active routers. In this environment, the active code authorized or trusted by privileged users is executed in the secure execution environment (EE) of the active router, while others are executed in the secure EE of the nodes in the distributed shared memory (DSM) cluster. With the supports of a multi-process Java virtual machine and KeyNote, untrusted active packets are controlled to securely consume resource. The DSM consistency management makes that active packets can be parallely processed in the DSM cluster as if they were processed one by one in ANTS (Active Network Transport System). We demonstrate that CSANE has good security and scalability, but imposing little changes on traditional routers. 展开更多
关键词 active networks SECURITY DSM
下载PDF
A Novel Active Network Architecture Based on Extensible Services Router
6
作者 徐恪 XU +4 位作者 Mingwei Wu Jianping Yu Zhongchao 《High Technology Letters》 EI CAS 2003年第2期51-56,共6页
Active networks are a new kind of packet-switched networks in which packets have code fragments that are executed on the intermediary nodes (routers). The code can extend or modify the foundation architecture of a net... Active networks are a new kind of packet-switched networks in which packets have code fragments that are executed on the intermediary nodes (routers). The code can extend or modify the foundation architecture of a network. In this paper, the authors present a novel active network architecture combined with advantages of two major active networks technology based on extensible services router. The architecture consists of extensible service router, active extensible components server and key distribution center (KDC). Users can write extensible service components with programming interface. At the present time, we have finished the extensible services router prototype system based on Highly Efficient Router Operating System (HEROS), active extensible components server and KDC prototype system based on Linux. 展开更多
关键词 computer networks extensible services active network AUTHENTICATION
下载PDF
Active Network系统的结构分析与研究
7
作者 马燕 《计算机科学》 CSCD 北大核心 2002年第4期89-92,共4页
现有的网络系统基于"端到端"的模型体系,是1984年由H.Salzer、D.Reed和D.Clark提出来的.在这种网络中,相关的计算和控制是在发送和接收"端点"进行的,在网络的结点上不对包进行处理.虽然在网络中路由器和交换机可以... 现有的网络系统基于"端到端"的模型体系,是1984年由H.Salzer、D.Reed和D.Clark提出来的.在这种网络中,相关的计算和控制是在发送和接收"端点"进行的,在网络的结点上不对包进行处理.虽然在网络中路由器和交换机可以改变包头,但是对用户的数据不做任何处理,因此目前的网络系统又称为是"被动网络". 展开更多
关键词 主动网络 计算机网络 路由器 交换机 activenetwork系统 结构分析
下载PDF
HSCP:a hardware and software combined platform to improve precision in active network measurement
8
作者 王志东 Li Wenfa +1 位作者 Xu Qingjie Mao Jianbiao 《High Technology Letters》 EI CAS 2014年第2期173-178,共6页
In this paper,an active network measurement platform is proposed which is a combination of hardware and software.Its innovation lies in the high performance of hardware combined with features that the software is easy... In this paper,an active network measurement platform is proposed which is a combination of hardware and software.Its innovation lies in the high performance of hardware combined with features that the software is easy to program,which retains software flexibility at the same time.By improving the precision of packet timestamp programmable hardware equipment,it provides packet sending control more accurately and supports the microsecond packet interval.We have implemented a model on the NetMagic platform,and done some experiments to analyze the accuracy difference of the user,the kernel and hardware timestamp. 展开更多
关键词 active network measurement TIMESTAMP packet transmission control
下载PDF
An Identified Study on the Active Network of a Thermoacoustic Regenerator 被引量:1
9
作者 Guozhong Ding Feng Wu +2 位作者 Gang Zhou Xiaoqing Zhang Jiuyang Yu 《Engineering(科研)》 2009年第1期16-22,共7页
An active thermo-acoustic network model of regenerator which is a key component to accomplish the con-version between thermal-and acoustic power in thermo-acoustic system has been established in this paper. The experi... An active thermo-acoustic network model of regenerator which is a key component to accomplish the con-version between thermal-and acoustic power in thermo-acoustic system has been established in this paper. The experiment was carried out to quantify the network. A method called least square is employed in order to identify the H matrix describing the system. The results obtained here show that the active thermo-acoustic network can reliably depict the characteristics of a thermo-acoustic system. 展开更多
关键词 REGENERATOR active network H MATRIX System IDENTIFICATION
下载PDF
EFFICIENT SIMULATION AND OPTIMIZATION OF LINEAR ACTIVE NETWORKS
10
作者 曲明 《Journal of Electronics(China)》 1990年第4期365-370,共6页
An efficient method for the optimization of linear networks is presented.Thecomputation cost in circuit optimization mainly depends on the simulation of network;in general,the simulation of a linear network needs to s... An efficient method for the optimization of linear networks is presented.Thecomputation cost in circuit optimization mainly depends on the simulation of network;in general,the simulation of a linear network needs to solve a high dimension linear algebra equation.Animportant characteristic in circuit optimization is that the number of independently tunableparameters is small.In terms of the property of linear networks,the circuit is described by amultiport network in the presented method,and the hybrid matrix is established.The dimensionof the equation to be solved is the same as the number of optimization parameters in objectivefunction evaluations,which provides a fast simulation tool for optimization. 展开更多
关键词 active network HYBRID MATRIX SIMULATION OPTIMIZATION
下载PDF
Study of an Active Network Management System
11
作者 Yan Ma Xiaozhen Zhang Xiaomei Liang 《通讯和计算机(中英文版)》 2006年第1期32-36,共5页
关键词 网络管理 信息包 网络技术 网络资源
下载PDF
Study of the Active Network Management System Model Based on Agent
12
作者 Xianchun Zou Weiqun Zhang +1 位作者 Yan Ma Runzhen Zhou 《通讯和计算机(中英文版)》 2006年第3期51-56,共6页
下载PDF
A Critical Review of Active Distribution Network Reconfiguration:Concepts,Development,and Perspectives
13
作者 Bo Yang Rui Zhang +10 位作者 Jie Zhang Xianlong Cheng Jiale Li Yimin Zhou Yuanweiji Hu Bin He Gongshuai Zhang Xiuping Du Si Ji Yiyan Sang Zhengxun Guo 《Energy Engineering》 EI 2024年第12期3487-3547,共61页
In recent years,the large-scale grid connection of various distributed power sources has made the planning and operation of distribution grids increasingly complex.Consequently,a large number of active distribution ne... In recent years,the large-scale grid connection of various distributed power sources has made the planning and operation of distribution grids increasingly complex.Consequently,a large number of active distribution network reconfiguration techniques have emerged to reduce system losses,improve system safety,and enhance power quality via switching switches to change the system topology while ensuring the radial structure of the network.While scholars have previously reviewed these methods,they all have obvious shortcomings,such as a lack of systematic integration of methods,vague classification,lack of constructive suggestions for future study,etc.Therefore,this paper attempts to provide a comprehensive and profound review of 52 methods and applications of active distribution network reconfiguration through systematic method classification and enumeration.Specifically,these methods are classified into five categories,i.e.,traditional methods,mathematical methods,meta-heuristic algorithms,machine learning methods,and hybrid methods.A thorough comparison of the various methods is also scored in terms of their practicality,complexity,number of switching actions,performance improvement,advantages,and disadvantages.Finally,four summaries and four future research prospects are presented.In summary,this paper aims to provide an up-to-date and well-rounded manual for subsequent researchers and scholars engaged in related fields. 展开更多
关键词 active distribution network RECONFIGURATION meta-heuristic algorithm machine learning
下载PDF
Analysis of Lavandulyl Flavonoids from Sophora flavescens with Antiinflammatory Activity Based on Molecular Network Technology
14
作者 Yan LIN Bo TU +1 位作者 Shanggao LIAO Minghui HE 《Medicinal Plant》 2024年第2期1-5,14,共6页
[Objectives]This study was conducted to screen lavandulyl flavonoids with anti-inflammatory activity from Sophora flavescens.[Methods]35 compounds were screened from traditional Chinese medicine S.flavescens using the... [Objectives]This study was conducted to screen lavandulyl flavonoids with anti-inflammatory activity from Sophora flavescens.[Methods]35 compounds were screened from traditional Chinese medicine S.flavescens using the nitric oxide(NO)anti-inflammatory activity model.[Results]Five components,8(xanthohumol),13(kurarinol),27(4-methoxysalicylic acid),28(b-resorcic acid)and 30(b-resorcic acid),exhibited significant anti-inflammatory activity,with IC 50 values of 5.99,4.76,6.96,3.41 and 5.22μM,respectively.Especially,8(xanthohumol)and 13(kurarinol)were typical lavandulyl flavonoids in S.flavescens,which were worth further exploration.Furthermore,UPLC-Q-Exactive and GNPS molecular networking technique were used for rapid analysis of lavandulyl flavonoids from S.flavescens.A total of 15 components were identified.[Conclusions]This work lays a theoretical foundation for further separation and analysis of lavandulyl flavonoids with anti-inflammatory activity from S.flavescens. 展开更多
关键词 Sophora flavescens Molecular network Anti-inflammatory activity Lavandulyl flavonoids
下载PDF
Active components of Bupleuri Radix in the treatment of schizophrenia analyzed by network pharmacology and clinical verification
15
作者 Jiang Xiao Jun Guo +6 位作者 Xin-Yu Zheng Wen Sun Qiu-Xiang Ning Li Tang Jian-Ying Xiao Liang Li Ping Yang 《Traditional Medicine Research》 2023年第11期14-22,共9页
Background:Bupleuri Radix is a common Chinese medicinal material in traditional Chinese medicine.Currently,the therapeutic effect of treating schizophrenia is relatively well understood.However,there are fewer studies... Background:Bupleuri Radix is a common Chinese medicinal material in traditional Chinese medicine.Currently,the therapeutic effect of treating schizophrenia is relatively well understood.However,there are fewer studies examining the underlying mechanisms of its treatment.The objective of the study was to investigate the primary mechanisms of Bupleuri Radix in treating schizophrenia through network pharmacology and clinical validation.Method:Network pharmacology revealed possible molecular mechanisms,followed by clinical verification.Sixty-seven schizophrenia patients undergoing treatment at the Hunan Brain Hospital between October and November 2022 were recruited and randomly divided into the olanzapine group and the olanzapine+Bupleuri Radix group.Additionally,32 healthy people undergoing physical examinations during the same period were included as the control group.The patient’s positive and negative symptom scale scores were compared.qPCR was used to detect the mRNA expression levels of ESR1,mTOR,EIF4E,and SMAD4 in peripheral blood.Results:Through network pharmacological analysis,it was concluded in this study that Bupleuri Radix might regulate the mTOR,PI3K-Akt,and HIF-1 signaling pathways.Clinical experiments indicated that compared with before treatment,the positive and negative symptom scale scores and total scores of the two treatment groups were significantly decreased after treatment(P<0.01).In addition,the positive and negative symptom scale scores and total scores in the olanzapine+Bupleuri Radix group were significantly decreased(P<0.01)compared to the olanzapine group after treatment.Before treatment,ESR1 mRNA expression levels in peripheral blood were significantly higher in the two treatment groups than in the control group,whereas the mRNA expression levels of mTOR,EIF4E,and SMAD4 in peripheral blood were significantly lower(P<0.01).The mRNA expression levels of mTOR,EIF4E,and SMAD4 in peripheral blood were significantly higher after therapy than before treatment,whereas the mRNA expression levels of ESR1 in peripheral blood were significantly lower(P<0.01).After therapy,the olanzapine+Bupleuri Radix group’s mRNA expression levels of mTOR,EIF4E,and SMAD4 were significantly higher than those of the olanzapine group,whereas the mRNA expression levels of ESR1 were significantly lower(P<0.01).Conclusion:The mechanism of Bupleuri Radix’s therapeutic efficacy in schizophrenia may involve the up-regulation of mTOR,EIF4E,and SMAD4 mRNA expression and the down-regulation of ESR1 mRNA expression in peripheral blood. 展开更多
关键词 SCHIZOPHRENIA Bupleuri Radix network pharmacology clinical verification active components
下载PDF
Optimal Location and Sizing of Distributed Generator via Improved Multi-Objective Particle Swarm Optimization in Active Distribution Network Considering Multi-Resource
16
作者 Guobin He Rui Su +5 位作者 Jinxin Yang Yuanping Huang Huanlin Chen Donghui Zhang Cangtao Yang Wenwen Li 《Energy Engineering》 EI 2023年第9期2133-2154,共22页
In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distribut... In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distributed generation(DG)based on renewable energy is critical for active distribution network operation enhancement.To comprehensively analyze the accessing impact of DG in distribution networks from various parts,this paper establishes an optimal DG location and sizing planning model based on active power losses,voltage profile,pollution emissions,and the economics of DG costs as well as meteorological conditions.Subsequently,multiobjective particle swarm optimization(MOPSO)is applied to obtain the optimal Pareto front.Besides,for the sake of avoiding the influence of the subjective setting of the weight coefficient,the decisionmethod based on amodified ideal point is applied to execute a Pareto front decision.Finally,simulation tests based on IEEE33 and IEEE69 nodes are designed.The experimental results show thatMOPSO can achieve wider and more uniformPareto front distribution.In the IEEE33 node test system,power loss,and voltage deviation decreased by 52.23%,and 38.89%,respectively,while taking the economy into account.In the IEEE69 test system,the three indexes decreased by 19.67%,and 58.96%,respectively. 展开更多
关键词 active distribution network multi-resource penetration operation enhancement particle swarm optimization multi-objective optimization
下载PDF
Blockchain-Based Power Transaction Method for Active Distribution Network
17
作者 Fei Zeng Zhinong Wei +1 位作者 Haiteng Han Yang Chen 《Energy Engineering》 EI 2023年第5期1067-1080,共14页
A blockchain-based power transaction method is proposed for Active Distribution Network(ADN),considering the poor security and high cost of a centralized power trading system.Firstly,the decentralized blockchain struc... A blockchain-based power transaction method is proposed for Active Distribution Network(ADN),considering the poor security and high cost of a centralized power trading system.Firstly,the decentralized blockchain structure of the ADN power transaction is built and the transaction information is kept in blocks.Secondly,considering the transaction needs between users and power suppliers in ADN,an energy request mechanism is proposed,and the optimization objective function is designed by integrating cost aware requests and storage aware requests.Finally,the particle swarm optimization algorithm is used for multi-objective optimal search to find the power trading scheme with the minimum power purchase cost of users and the maximum power sold by power suppliers.The experimental demonstration of the proposed method based on the experimental platform shows that when the number of participants is no more than 10,the transaction delay time is 0.2 s,and the transaction cost fluctuates at 200,000 yuan,which is better than other comparison methods. 展开更多
关键词 Blockchain active distribution network power transaction energy request mechanism particle swarm optimization algorithm
下载PDF
Application of DSAPSO Algorithm in Distribution Network Reconfiguration with Distributed Generation
18
作者 Caixia Tao Shize Yang Taiguo Li 《Energy Engineering》 EI 2024年第1期187-201,共15页
With the current integration of distributed energy resources into the grid,the structure of distribution networks is becoming more complex.This complexity significantly expands the solution space in the optimization p... With the current integration of distributed energy resources into the grid,the structure of distribution networks is becoming more complex.This complexity significantly expands the solution space in the optimization process for network reconstruction using intelligent algorithms.Consequently,traditional intelligent algorithms frequently encounter insufficient search accuracy and become trapped in local optima.To tackle this issue,a more advanced particle swarm optimization algorithm is proposed.To address the varying emphases at different stages of the optimization process,a dynamic strategy is implemented to regulate the social and self-learning factors.The Metropolis criterion is introduced into the simulated annealing algorithm to occasionally accept suboptimal solutions,thereby mitigating premature convergence in the population optimization process.The inertia weight is adjusted using the logistic mapping technique to maintain a balance between the algorithm’s global and local search abilities.The incorporation of the Pareto principle involves the consideration of network losses and voltage deviations as objective functions.A fuzzy membership function is employed for selecting the results.Simulation analysis is carried out on the restructuring of the distribution network,using the IEEE-33 node system and the IEEE-69 node system as examples,in conjunction with the integration of distributed energy resources.The findings demonstrate that,in comparison to other intelligent optimization algorithms,the proposed enhanced algorithm demonstrates a shorter convergence time and effectively reduces active power losses within the network.Furthermore,it enhances the amplitude of node voltages,thereby improving the stability of distribution network operations and power supply quality.Additionally,the algorithm exhibits a high level of generality and applicability. 展开更多
关键词 Reconfiguration of distribution network distributed generation particle swarm optimization algorithm simulated annealing algorithm active network loss
下载PDF
Impact of tropospheric modelling on GNSS vertical precision:an empirical analysis based on a local active network 被引量:1
19
作者 MªSelmira Garrido MªClara de Lacy Ana MªRojas 《International Journal of Digital Earth》 SCIE EI 2018年第9期880-896,共17页
The troposphere affects Global Navigation Satellite System(GNSS)signals due to the variability of the refractive index.Tropospheric delay is a function of the satellite elevation angle and the altitude of the GNSS rec... The troposphere affects Global Navigation Satellite System(GNSS)signals due to the variability of the refractive index.Tropospheric delay is a function of the satellite elevation angle and the altitude of the GNSS receiver and depends on the atmospheric parameters.If the residual tropospheric delay is not modelled carefully a bias error will occur in the vertical component.In order to analyse the precise altimetric positioning based on a local active network,four scenarios in Southern Spain with different topographical,environmental,and meteorological conditions are presented,considering both favourable and non-favourable conditions.The use of surface meteorological observations allows us to take into account the tropospheric conditions instead of a standard atmosphere,but introduces a residual tropospheric bias which reduces the accuracy of precise GNSS positioning.Thus,with short observation times it is recommended not to estimate troposphere parameters,but to use an a priori model together with the standard atmosphere.The results confirm that it is possible to achieve centimetre-scale vertical accuracy and precision with real time kinematic positioning even with large elevation differences with respect to the nearest reference stations.These numerical results may be taken into consideration for improving the altimetric configuration of the local active network. 展开更多
关键词 ALTIMETRY GNSS meteorological data active network tropospheric refraction
原文传递
Network Configuration Entity Extraction Method Based on Transformer with Multi-Head Attention Mechanism
20
作者 Yang Yang Zhenying Qu +2 位作者 Zefan Yan Zhipeng Gao Ti Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期735-757,共23页
Nowadays,ensuring thequality of networkserviceshas become increasingly vital.Experts are turning toknowledge graph technology,with a significant emphasis on entity extraction in the identification of device configurat... Nowadays,ensuring thequality of networkserviceshas become increasingly vital.Experts are turning toknowledge graph technology,with a significant emphasis on entity extraction in the identification of device configurations.This research paper presents a novel entity extraction method that leverages a combination of active learning and attention mechanisms.Initially,an improved active learning approach is employed to select the most valuable unlabeled samples,which are subsequently submitted for expert labeling.This approach successfully addresses the problems of isolated points and sample redundancy within the network configuration sample set.Then the labeled samples are utilized to train the model for network configuration entity extraction.Furthermore,the multi-head self-attention of the transformer model is enhanced by introducing the Adaptive Weighting method based on the Laplace mixture distribution.This enhancement enables the transformer model to dynamically adapt its focus to words in various positions,displaying exceptional adaptability to abnormal data and further elevating the accuracy of the proposed model.Through comparisons with Random Sampling(RANDOM),Maximum Normalized Log-Probability(MNLP),Least Confidence(LC),Token Entrop(TE),and Entropy Query by Bagging(EQB),the proposed method,Entropy Query by Bagging and Maximum Influence Active Learning(EQBMIAL),achieves comparable performance with only 40% of the samples on both datasets,while other algorithms require 50% of the samples.Furthermore,the entity extraction algorithm with the Adaptive Weighted Multi-head Attention mechanism(AW-MHA)is compared with BILSTM-CRF,Mutil_Attention-Bilstm-Crf,Deep_Neural_Model_NER and BERT_Transformer,achieving precision rates of 75.98% and 98.32% on the two datasets,respectively.Statistical tests demonstrate the statistical significance and effectiveness of the proposed algorithms in this paper. 展开更多
关键词 Entity extraction network configuration knowledge graph active learning TRANSFORMER
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部