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Resource Search in Unstructured Peer-to-Peer System Based on Multiple-Tree Overlay Structure 被引量:1
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作者 YU Jianqiao LIAO Jianwei 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期887-892,共6页
We propose a multiple-tree overlay structure for resource discovery in unstructured P2P systems. Peers that have similar interests or hold similar type of resources will be grouped into a tree-like cluster. We exploit... We propose a multiple-tree overlay structure for resource discovery in unstructured P2P systems. Peers that have similar interests or hold similar type of resources will be grouped into a tree-like cluster. We exploit the heterogeneity of peers in each cluster by connecting peers with more capacities closer to the root of the tree. The capacity of a peer can be defined in different ways (e.g. higher network bandwidth, larger disk space, more data items of a certain type etc.) according to different needs of users or applications. 展开更多
关键词 unstructured P2P system tree-like cluster similar interest
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ISS:Efficient Search Scheme Based on Immune Method in Modern Unstructured Peer-to-Peer Networks
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作者 GUAN Zhitao CAO Yuanda ZHU Liehuang ZHANG Changyou FAN Xiumei 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期866-870,共5页
Flooding is the most famous technique for locating contents in unstructured P2P networks. Recently traditional flooding has been replaced by more efficient dynamic query (DQ) and different variants of such algorithm... Flooding is the most famous technique for locating contents in unstructured P2P networks. Recently traditional flooding has been replaced by more efficient dynamic query (DQ) and different variants of such algorithms. Dynamic query is a new flooding technique which could estimate a proper time-to-live (TTL) value for a query flooding by estimating the popularity of the searched files, and retrieve sufficient results under controlled flooding range for reducing network traffic. However, all DQ-like search algorithms are "blind" so that a large amount of redundant messages are caused. In this paper, we proposed a new search scheme, called Immune Search Scheme (ISS), to cope with this problem. In ISS, an immune systems inspired concept of similarity-governed clone proliferation and mutation for query message movement is applied. Some assistant strategies, that is, shortcuts creation and peer traveling are incorporated into ISS to develop "immune memory" for improving search performance, which can make ISS not be blind but heuristic. 展开更多
关键词 peer-to-peer dynamic query immune method clone proliferation and mutation
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Modeling and Defending Passive Worms over Unstructured Peer-to-Peer Networks 被引量:8
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作者 王方伟 张运凯 马建峰 《Transactions of Tianjin University》 EI CAS 2008年第1期66-72,共7页
Passive worms can passively propagate through embedding themselves into some sharing files, which can result in significant damage to unstructured P2P networks. To study the passive worm behaviors, this paper firstly ... Passive worms can passively propagate through embedding themselves into some sharing files, which can result in significant damage to unstructured P2P networks. To study the passive worm behaviors, this paper firstly analyzes and obtains the average delay for all peers in the whole transmitting process due to the limitation of network throughput, and then proposes a mathematical model for the propagation of passive worms over the unstructured P2P networks. The model mainly takes the effect of the network throughput into account, and applies a new healthy files dissemination-based defense strategy according to the file popularity which follows the Zipf distribution. The simulation results show that the propagation of passive worms is mainly governed by the number of hops, initially infected files and uninfected files. The larger the number of hops, the more rapidly the passive worms propagate. If the number of the initially infected files is increased by the attackers, the propagation speed of passive worms increases obviously. A larger size of the uninfected file results in a better attack performance. However, the number of files generated by passive worms is not an important factor governing the propagation of passive worms. The effectiveness of healthy files dissemination strategy is verified. This model can provide a guideline in the control of unstructured P2P networks as well as passive worm defense. 展开更多
关键词 network security unstructured peer-to-peer networks passive worms propagationmodel patch dissemination strategy
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Survey on Anonymity in Unstructured Peer-to-Peer Systems
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作者 肖人毅 《Journal of Computer Science & Technology》 SCIE EI CSCD 2008年第4期660-671,共12页
Although anonymizing Peer-to-Peer (P2P) networks often means extra cost in terms of transfer efficiency, many systems try to mask the identities of their users for privacy consideration. By comparison and analysis o... Although anonymizing Peer-to-Peer (P2P) networks often means extra cost in terms of transfer efficiency, many systems try to mask the identities of their users for privacy consideration. By comparison and analysis of existing approaches, we investigate the properties of unstructured P2P anonymity, and summarize current attack models on these designs. Most of these approaches are path-based, which require peers to pre-construct anonymous paths before transmission, thus suffering significant overhead and poor reliability. We also discuss the open problems in this field and propose several future research directions. 展开更多
关键词 unstructured peer-to-peer systems mutual anonymity PRIVACY distributed system
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Proactive worm propagation modeling and analysis in unstructured peer-to-peer networks 被引量:3
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作者 Xiao-song ZHANG Ting CHEN +1 位作者 Jiong ZHENG Hua LI 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2010年第2期119-129,共11页
It is universally acknowledged by network security experts that proactive peer-to-peer (P2P) worms may soon en-gender serious threats to the Internet infrastructures. These latent threats stimulate activities of model... It is universally acknowledged by network security experts that proactive peer-to-peer (P2P) worms may soon en-gender serious threats to the Internet infrastructures. These latent threats stimulate activities of modeling and analysis of the proactive P2P worm propagation. Based on the classical two-factor model,in this paper,we propose a novel proactive worm propagation model in unstructured P2P networks (called the four-factor model) by considering four factors:(1) network topology,(2) countermeasures taken by Internet service providers (ISPs) and users,(3) configuration diversity of nodes in the P2P network,and (4) attack and defense strategies. Simulations and experiments show that proactive P2P worms can be slowed down by two ways:improvement of the configuration diversity of the P2P network and using powerful rules to reinforce the most connected nodes from being compromised. The four-factor model provides a better description and prediction of the proactive P2P worm propagation. 展开更多
关键词 Proactive peer-to-peer (P2P) worm propagation modeling Network topology Configuration diversity Attack and defense strategies Four-factor model
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Large Language Model in Healthcare for the Prediction of Genetic Variants from Unstructured Text Medicine Data Using Natural Language Processing
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作者 Noor Ayesha Muhammad Mujahid +2 位作者 Abeer Rashad Mirdad Faten S.Alamri Amjad R.Khan 《Computers, Materials & Continua》 2025年第7期1883-1899,共17页
Large language models(LLMs)and natural language processing(NLP)have significant promise to improve efficiency and refine healthcare decision-making and clinical results.Numerous domains,including healthcare,are rapidl... Large language models(LLMs)and natural language processing(NLP)have significant promise to improve efficiency and refine healthcare decision-making and clinical results.Numerous domains,including healthcare,are rapidly adopting LLMs for the classification of biomedical textual data in medical research.The LLM can derive insights from intricate,extensive,unstructured training data.Variants need to be accurately identified and classified to advance genetic research,provide individualized treatment,and assist physicians in making better choices.However,the sophisticated and perplexing language of medical reports is often beyond the capabilities of the devices we now utilize.Such an approach may result in incorrect diagnoses,which could affect a patient’s prognosis and course of therapy.This study evaluated the efficacy of the proposed model by looking at publicly accessible textual clinical data.We have cleaned the clinical textual data using various text preprocessing methods,including stemming,tokenization,and stop word removal.The important features are extracted using Bag of Words(BoW)and Term Frequency-Inverse Document Frequency(TFIDF)feature engineering methods.The important motive of this study is to predict the genetic variants based on the clinical evidence using a novel method with minimal error.According to the experimental results,the random forest model achieved 61%accuracy with 67%precision for class 9 using TFIDF features and 63%accuracy and a 73%F1 score for class 9 using Bag of Words features.The accuracy of the proposed BERT(Bidirectional Encoder Representations from Transformers)model was 70%with 5-fold cross-validation and 71%with 10-fold cross-validation.The research results provide a comprehensive overview of current LLM methods in healthcare,benefiting academics as well as professionals in the discipline. 展开更多
关键词 LLM unstructured data GENETICS PREDICTION healthcare MEDICINE
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CFH-Net:Transformer-Based Unstructured Road-Free Space Detection Network
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作者 Jingcheng Yang Lili Fan Hongmei Liu 《Computers, Materials & Continua》 2025年第6期4725-4740,共16页
With the advancement of deep learning in the automotive domain,more and more researchers are focusing on autonomous driving.Among these tasks,free space detection is particularly crucial.Currently,many model-based app... With the advancement of deep learning in the automotive domain,more and more researchers are focusing on autonomous driving.Among these tasks,free space detection is particularly crucial.Currently,many model-based approaches have achieved autonomous driving on well-structured urban roads,but these efforts primarily focus on urban road environments.In contrast,there are fewer deep learningmethods specifically designed for off-road traversable area detection,and their effectiveness is not yet satisfactory.This is because detecting traversable areas in complex outdoor environments poses significant challenges,and current methods often rely on single-image inputs,which do not align with contemporary multimodal approaches.Therefore,in this study,we propose a CFH-Net model for off-road traversable area detection.This model employs a Transformer architecture to enhance its capability of capturing global information.For multimodal feature extraction and fusion,we integrate the CM-FRM module for feature extraction and introduce the novel FFX module for feature fusion,thereby improving the perception capability of autonomous vehicles on unstructured roads.To address upsampling,we propose a new convolution precorrection method to reduce model parameters and computational complexity while enhancing the model’s ability to capture complex features.Finally,we conducted experiments on the ORFD off-road dataset and achieved outstanding results. 展开更多
关键词 Freespace detection semantic segmentation terrain perception unstructured environment
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Optimal Peer-to-Peer Coupled Electricity and Carbon Trading in Distribution Networks
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作者 Huangqi Ma Yue Xiang +2 位作者 Alexis Pengfei Zhao Shuangqi Li Junyong Liu 《Engineering》 2025年第8期37-48,共12页
The surge of distributed renewable energy resources has given rise to the emergence of prosumers,facilitating the low-carbon transition of distribution networks.However,flexible prosumers introduce bidirectional power... The surge of distributed renewable energy resources has given rise to the emergence of prosumers,facilitating the low-carbon transition of distribution networks.However,flexible prosumers introduce bidirectional power and carbon interaction,increasing the complexity of practical decision-making in distribution networks.To address these challenges,this paper presents a carbon-coupled network charge-guided bi-level interactive optimization method between the distribution system operator and prosumers.In the upper level,a carbon-emission responsibility settlement method that incorporates the impact of peer-to-peer(P2P)trading is proposed,based on a carbon-emission flow model and optimal power flow model,leading to the formulation of carbon-coupled network charges.In the lower level,a decentralized P2P trading mechanism is developed to achieve the clearing of energy and carbon-emission rights.Furthermore,an alternating direction method of multipliers with an adaptive penalty factor is introduced to address the equilibrium of the P2P electricity–carbon coupled market,and an improved bisection method is employed to ensure the convergence of the bi-level interaction.A case study on the modified IEEE 33-bus system demonstrates the effectiveness of the proposed model and methodology. 展开更多
关键词 Prosumer Network charge Carbon-emission rights peer-to-peer trading
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Adaptive Vibration-Driven Tensegrity in Unstructured Environments
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作者 Ruhe Mei Ruizhi Liu +1 位作者 Yafeng Wang Xian Xu 《Journal of Bionic Engineering》 2025年第5期2354-2366,共13页
Tensegrity structures,embodying the principles of continuous tensioning and discrete compression,have emerged as fundamental frameworks in locomotive soft robotics for navigating uneven and unpredictable environments,... Tensegrity structures,embodying the principles of continuous tensioning and discrete compression,have emerged as fundamental frameworks in locomotive soft robotics for navigating uneven and unpredictable environments,owing to their flexible and resilient traits.By means of a straightforward and cost-effective method to achieve structure-driven,vibration-driven tensegrity shows great potential,particularly in tasks demanding random exploration.However,the design guidance for vibration-driven tensegrity and their performance evaluation in unstructured terrain remain unrevealed due to the complex dynamics of the structure.This paper presents a small six-bar tensegrity robot,driven by wireless vibration motors,designed for deployment in disaster rescue and search scenarios.Finite element simulation is used to investigate how structural characteristics,excitation parameters,and the arrangement of motors affect the kinematic performance of this tensegrity system.A prototype of the six-bar tensegrity robot with three motors located on the lower ends of the three lower struts is designed and manufactured after the numerical simulations.A simple control policy which adjusts the motion of the tensegrity robot by turning on or off the motors on different locations is proposed.The prototype with and without the control policy is tested in man-made environments of various complexity.It shows that the ability and efficiency of the tensegrity robot in exploring unstructured environments is significantly enhanced by the proposed control policy.It is believed that the potential of the vibration-driven tensegrity robot could be further exploited by integrating multi-source sensors and more intelligent control policies. 展开更多
关键词 Finite element simulation Parametric design TENSEGRITY unstructured environment VIBRATION
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Vortex-Induced Vibration Prediction in Floating Structures via Unstructured CFD and Attention-Based Convolutional Modeling
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作者 Yan Li YibinWu Bo Zhang 《Fluid Dynamics & Materials Processing》 2025年第12期2905-2925,共21页
Traditional Computational Fluid Dynamics(CFD)simulations are computationally expensive when applied to complex fluid–structure interaction problems and often struggle to capture the essential flow features governing ... Traditional Computational Fluid Dynamics(CFD)simulations are computationally expensive when applied to complex fluid–structure interaction problems and often struggle to capture the essential flow features governing vortex-induced vibrations(VIV)of floating structures.To overcome these limitations,this study develops a hybrid framework that integrates high-fidelity CFD modeling with deep learning techniques to enhance the accuracy and efficiency of VIV response prediction.First,an unstructured finite-volume fluid–structure coupling model is established to generate high-resolution flow field data and extract multi-component time-series feature tensors.These tensors serve as inputs to a Squeeze-and-Excitation Convolutional Neural Network(SE-CNN),which models the nonlinear coupling between flow disturbances and structural responses.The SE-CNN architecture incorporates an attention-based weighting mechanism through an embedded Squeeze-and-Excitation module,dynamically optimizing channel feature importance and improving sensitivity to critical flow characteristics.During training,multidimensional inputs,including pressure,velocity gradient,and displacement sequences,are used to capture the full complexity of fluid–structure interactions.Results demonstrate that the proposed method achieves a maximum amplitude prediction error of only 2.9%and a main frequency deviation below 0.03 Hz,outperforming conventional CNN models by reducing amplitude prediction error from 3.2%to 1.9%.The approach is validated using a representative semi-submersible platform,confirming its robustness across varying damping conditions and flow velocities. 展开更多
关键词 unstructured grid computational fluid dynamics squeeze-and-excitation convolutional neural network vortex-induced vibration floating structure
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PeerIS:基于Peer-to-Peer的信息检索系统 被引量:29
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作者 凌波 陆志国 +2 位作者 黄维雄 钱卫宁 周傲英 《软件学报》 EI CSCD 北大核心 2004年第9期1375-1384,共10页
介绍了对等计算(peer-to-peer,简称 P2P)的特征、潜在优势和应用范围,指出了当前 P2P 数据共享系统(甚至缺乏语义)和粗粒度(文件水平)共享等局限性.针对这种现状,提出了基于 P2P 的信息检索,既可充分发掘 P2P 技术的潜在优势,克服传统... 介绍了对等计算(peer-to-peer,简称 P2P)的特征、潜在优势和应用范围,指出了当前 P2P 数据共享系统(甚至缺乏语义)和粗粒度(文件水平)共享等局限性.针对这种现状,提出了基于 P2P 的信息检索,既可充分发掘 P2P 技术的潜在优势,克服传统信息检索系统的可伸缩瓶颈等问题,又可实现 P2P 数据共享系统语义丰富和细粒度的信息检索与共享;并开发出 PeerIS:基于 P2P 的信息检索系统.描述了 PeerIS 的整体构架与节点的内部结构;重点阐述了 PeerIS 的通信机制、自配置机制、查询机制以及自适应路由机制等实现关键技术;并用实验证明了 PeerIS 的优异性. 展开更多
关键词 peer-to-peer 信息检索
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应用于移动互联网的Peer-to-Peer关键技术 被引量:20
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作者 李伟 徐正全 杨铸 《软件学报》 EI CSCD 北大核心 2009年第8期2199-2213,共15页
对现有的应用于移动互联网的P2P技术方面的研究进行了分析.首先介绍了P2P技术和移动互联网的概念,并提出将P2P技术应用在移动互联网所面临的挑战和应用模式.其次,分别针对集中式架构、超级节点体系架构和ad hoc架构对应用于互联网的P2P... 对现有的应用于移动互联网的P2P技术方面的研究进行了分析.首先介绍了P2P技术和移动互联网的概念,并提出将P2P技术应用在移动互联网所面临的挑战和应用模式.其次,分别针对集中式架构、超级节点体系架构和ad hoc架构对应用于互联网的P2P网络体系架构进行了阐述.再其次,针对移动终端的两种接入模式,分别在资源定位算法和跨层优化两个方面进行了介绍.对各关键技术的特点进行了详细的分析,指出其存在的不足.最后,对未来的工作进行了展望. 展开更多
关键词 移动互联网 peer-to-peer MOBILE AD HOC 资源定位
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基于贝叶斯网络的Peer-to-Peer识别方法 被引量:11
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作者 李君 张顺颐 +1 位作者 王浩云 李翠莲 《应用科学学报》 CAS CSCD 北大核心 2009年第2期124-130,共7页
网络业务分类与识别是网络管理、网络规划和安全的必要途径,而Peer-to-Peer(P2P)流量由于采用伪装端口、动态端口以及应用层加密,已成为业务分类与识别的主要难点.该文提出了P2P业务的精确识别方法,通过对流统计特性的分析,提取相关特... 网络业务分类与识别是网络管理、网络规划和安全的必要途径,而Peer-to-Peer(P2P)流量由于采用伪装端口、动态端口以及应用层加密,已成为业务分类与识别的主要难点.该文提出了P2P业务的精确识别方法,通过对流统计特性的分析,提取相关特征属性,应用遗传算法选取最优特征属性子集,并采用贝叶斯网络机器学习方法识别P2P流量.实验表明K2,TAN和BAN能有效快速地识别P2P业务,分类精度高达95%以上,很大程度上优于朴素贝叶斯分类和BP神经网络方法.同时该系统具有可扩展性,能够识别未知的P2P流量,并适用于实时分类识别环境. 展开更多
关键词 peer-to-peer 流量识别 朴素贝叶斯 贝叶斯网络
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分布式Peer-to-Peer网络Gnutella模型研究 被引量:23
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作者 黄道颖 李祖鹏 +2 位作者 庄雷 黄建华 张安琳 《计算机工程与应用》 CSCD 北大核心 2003年第5期60-63,共4页
计算机对等联网(peer-to-peernetwork,P2P)技术是目前新一代网络技术研究的活跃领域,而P2P网络模型研究是P2P网络技术研究的重要环节。该文着重介绍了Gnutella网络模型的体系结构及工作原理,分析了其优缺点。并对其未来发展改进前景进... 计算机对等联网(peer-to-peernetwork,P2P)技术是目前新一代网络技术研究的活跃领域,而P2P网络模型研究是P2P网络技术研究的重要环节。该文着重介绍了Gnutella网络模型的体系结构及工作原理,分析了其优缺点。并对其未来发展改进前景进行了展望。 展开更多
关键词 分布式peer-to-peer网络 Gnutella模型 计算机对等联网 活动对等点 扩散路由
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Internet中Peer-to-Peer应用流量测量与分析 被引量:7
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作者 张云飞 雷连虹 陈常嘉 《铁道学报》 EI CAS CSCD 北大核心 2004年第5期55-60,共6页
Peer to Peer网络(简称p2p)作为一种新型的覆盖网络引起了越来越多研究者的兴趣。本文介绍了在我国进行的骨干互联网上p2p网络流量测量。与现有国外研究不同,本文的数据来源于核心路由器,因此克服了它们的缺陷。其研究集中在汇聚流中的... Peer to Peer网络(简称p2p)作为一种新型的覆盖网络引起了越来越多研究者的兴趣。本文介绍了在我国进行的骨干互联网上p2p网络流量测量。与现有国外研究不同,本文的数据来源于核心路由器,因此克服了它们的缺陷。其研究集中在汇聚流中的3个周期性尖峰群、不同主机发送或接收流量的重尾分布、p2p流量的长相关特性以及提出了ADTE的估计方法来区分信令和数据流量。本文的研究也显示出Napster在p2p流中占大部分,这暗示着超级节点和阶层式拓扑较纯p2p结构潜在的优势。同时,观察到在我国p2p的流量仅占Internet总流量的1%弱,这个值跟国外的数据有很大区别。我们分析了其中的原因并希望该结论为我国p2p软件的发展提供参考。 展开更多
关键词 网络测量 peer-to-peer 数据挖掘 长相关
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主动peer-to-peer网络架构 被引量:2
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作者 陈华 钱剑飞 俞瑞钊 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2004年第5期554-558,576,共6页
针对当前peer-to-peer(P2P)网络只能通过固定的协议和服务有限地利用节点资源的弱点提出了主动P2P网络(APN)架构.结合P2P网络技术和主动网络技术,核心思想是把P2P网络的服务和协议代码封装在数据包中,随着数据包一起传送,并由需要的节... 针对当前peer-to-peer(P2P)网络只能通过固定的协议和服务有限地利用节点资源的弱点提出了主动P2P网络(APN)架构.结合P2P网络技术和主动网络技术,核心思想是把P2P网络的服务和协议代码封装在数据包中,随着数据包一起传送,并由需要的节点加载和执行,由此完成服务和协议的动态扩充和部署.通过在APN上部署自动代码理解和查询系统,验证了APN比现有P2P网络更能充分利用节点资源,更灵活,易于管理,同时,APN在安全性和性能方面的相对降低是可接受的. 展开更多
关键词 主动网络 peer-to-peer 网络架构
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基于Peer-to-Peer的单点登录服务研究和实现 被引量:2
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作者 刘艳 常丰峰 阎保平 《计算机应用研究》 CSCD 北大核心 2006年第5期222-224,共3页
使用Peer-to-Peer模型设计了一种新的单点登录服务模型,并在国家科技基础条件平台门户应用系统的身份认证系统中实际应用。该方案(NPSSO)把身份认证分配到多个身份认证服务器上,每个身份认证服务器均由一个单独的管理系统来管理,能够大... 使用Peer-to-Peer模型设计了一种新的单点登录服务模型,并在国家科技基础条件平台门户应用系统的身份认证系统中实际应用。该方案(NPSSO)把身份认证分配到多个身份认证服务器上,每个身份认证服务器均由一个单独的管理系统来管理,能够大大提高容错和抗攻击能力,并且能保证系统在用户和服务的数量上具有良好的可扩展性。最后,对该套单点登录方案进行了性能分析和相关工作的比较。 展开更多
关键词 peer-to-peer 身份认证 单点登录 SSO
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基于遗传算法的Peer-to-Peer路由算法R-GA 被引量:3
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作者 王涛 卢显良 《计算机应用研究》 CSCD 北大核心 2007年第1期316-317,320,共3页
路由算法是制约Peer-to-Peer系统整体性能的关键因素之一。目前大多数路由算法无法保证全局收敛,而链路延迟、费用、网络带宽等现实制约因素往往在选路时被忽略。针对上述问题,提出了基于遗传算法的R-GA路由算法。通过适度函数和遗传因... 路由算法是制约Peer-to-Peer系统整体性能的关键因素之一。目前大多数路由算法无法保证全局收敛,而链路延迟、费用、网络带宽等现实制约因素往往在选路时被忽略。针对上述问题,提出了基于遗传算法的R-GA路由算法。通过适度函数和遗传因子,R-GA可以快速地实现全局收敛。同时将链路的延迟、费用、带宽等参数插入到适度函数中,避免了盲目路由。仿真试验的结果表明,R-GA路由算法在大规模Peer-to-Peer系统中是高效和可扩展的。 展开更多
关键词 路由 peer-to-peer 遗传算法 适度函数
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UPWIND SCHEME FOR IDEAL 2-D MHD FLOWS BASED ON UNSTRUCTURED MESH 被引量:2
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作者 潘勇 王江峰 伍贻兆 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期1-7,共7页
An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (... An upwind scheme based on the unstructured mesh is developed to solve ideal 2-D magnetohydrodynamics (MHD) equations. The inviscid fluxes are approximated by using the modified advection upstream splitting method (AUSM) scheme, and a 5-stage explicit Runge-Kutta scheme is adopted in the time integration. To avoid the influence of the magnetic field divergence created during the simulation, the hyperbolic divergence cleaning method is introduced. The shock-capturing properties of the method are verified by solving the MHD shock-tube problem. Then the 2-D nozzle flow with the magnetic field is numerically simulated on the unstructured mesh. Computational results demonstrate the effects of the magnetic field and agree well with those from references. 展开更多
关键词 ideal magnetohydrodynamics equation unstructured mesh advection upstream splitting method(AUSM) scheme divergence cleaning
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一种基于Peer-to-Peer的分布式文件共享框架 被引量:2
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作者 张颖峰 李毓麟 《计算机工程》 CAS CSCD 北大核心 2003年第13期145-147,共3页
主要探讨了在基于非集中式Peer to Peer网络中实现分布式文件共享和传输管理需要考虑的主要因素,给出了基于Gnutella框架的改进之处以及实现细节,并提出了以通信自相似性和拓扑幂律分布相结合的特性模型。
关键词 peer-to-peer GNUTELLA 自相似 重尾分布 分布式文件共享框架
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