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Rare Bilateral Radius and Ulna Fractures: A Case Report
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作者 Kwabena Nana Achiaw Dankwa Ekins Kuuzie Samuel Kwame Ofori 《Open Journal of Orthopedics》 2024年第1期1-11,共11页
Introduction: Forearm fractures involving both the radius and ulna, present distinctive challenges in orthopedic trauma management. This case report explores the complexities of a rare case of bilateral fractures, emp... Introduction: Forearm fractures involving both the radius and ulna, present distinctive challenges in orthopedic trauma management. This case report explores the complexities of a rare case of bilateral fractures, emphasizing the importance of a comprehensive approach for optimal outcomes. Case Presentation: This report presents the case of a 40-year-old motorcyclist who was involved in a road accident and arrived at the emergency department shortly after the incident. Clinical examination revealed closed fractures in both forearms with mild swelling and severe tenderness. Fortunately, no neurovascular issues or compartment syndrome were detected. The patient was administered intravenous fluids and effective pain relief. Forearm splints were applied and the arms were elevated using pillows. Radiographs showed fractures in the right distal radius and ulna, as well as the left mid-shaft radius and ulna. Under general anesthesia, open reduction and internal fixation were per-formed using plates and screws for all four fractures. Postoperatively, the patient’s arms were immobilized and elevated, with gradual recovery during follow-up appointments over six months, eventually achieving full function without complaints. Conclusion: This article highlights the possibility, although infrequent, of bilateral shaft fractures of the ulna and radius. With thorough clinical assessment and radiological investigation, such fractures can be well-defined. The required definitive treatment, which usually involves open reduction and internal fixation, can be performed. 展开更多
关键词 FOREARM FRACTURE ULNAR radius BILATERAL
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Wind-sand flow simulation and radius optimization of highway embankment under different vertical curve radius
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作者 LI Liangying LI Qi +2 位作者 WANG Xu XIN Guowei WANG Zhenqiang 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2533-2546,共14页
It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius fo... It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius for reducing the risk of sand accumulation.In this study,three-dimensional models of desert highway embankments with different vertical curve radii were constructed,and Fluent software was used to simulate the wind-sand flow field and sand accumulation distribution of vertical curve embankments.The results show that:(1)Along the direction of the road,the concave and the convex vertical curve embankments have the effect of collecting and diverging the wind-sand flow,respectively.When the radius of the concave vertical curve is 3000 m,5000 m,8000 m,10000 m and 20000 m,the wind velocity in the middle of the vertical curve is 31.76%,22.58%,10.78%,10.53%and 10.44%,higher than that at both ends.When the radius of the convex vertical curve is 6500 m,8000 m,10000 m,20000 m and 30000 m,the wind velocity at both ends of the vertical curve is 14.06%,9.99%,6.14%,3.22%and 2.41%,higher than that in the middle.The diversion effect also decreases with the increase of the radius.(2)The conductivity of the concave and convex vertical curve embankments with different radii is greater than 1,which is the sediment transport roadbed.The conductivity increases with the increase of radius and gradually tends to be stable.When the radius of the concave and convex vertical curves reaches 8000 m and 20000 m respectively,the phenomenon of sand accumulation is no longer serious.Under the same radius condition,the concave vertical curve embankment is more prone to sand accumulation than the convex one.(3)Considering the strength of the collection and diversion of the vertical curve embankment with different radii,and the sand accumulation of the vertical curve embankment in the desert section of Wuma Expressway,the radius of the concave vertical curve is not less than 8000 m,and the radius of the convex vertical curve is not less than 20000 m,which can effectively reduce the sand accumulation of the vertical curve embankment.In the desert highway area,the research results of this paper can provide reference for the design of vertical curve to ensure the safe operation of desert highway. 展开更多
关键词 Highway engineering Vertical curve Numerical simulation Embankment wind-sand flow radius optimization
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Nuclear charge radius predictions by kernel ridge regression with odd-even effects
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作者 Lu Tang Zhen-Hua Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期94-102,共9页
The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear models.These are:(i)the isospin-dependent A^(... The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear models.These are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-Bogoliubov(RCHB)theory,(iii)Hartree-Fock-Bogoliubov(HFB)model HFB25,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFB25*model.In the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFB25 models,respectively.For each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number Z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR method.The best among them was the RCHB model,with a root-mean-square deviation of 0.0092 fm.The extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR method.The strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method. 展开更多
关键词 Nuclear charge radius Machine learning Kernel ridge regression method
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Revisiting the Electron Radius in Light of Length Contraction
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作者 Julie Marty 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1743-1748,共6页
In previous work, the electron radius was identified as the “actual electron radius.” However, this is more accurately described as the electron radius at rest. This study reexamines the electron with an emphasis on... In previous work, the electron radius was identified as the “actual electron radius.” However, this is more accurately described as the electron radius at rest. This study reexamines the electron with an emphasis on the electron radius under motion, incorporating the effects of length contraction. The findings suggest that the radius is subject to Lorentz contraction, which has interesting implications for relativistic effects at the subatomic level. 展开更多
关键词 Electron radius Length Contraction Lorentz Factor Relativistic Effects Subatomic Particles Compton Scattering
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Anisotropy of Trabecular Bone from Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jian-Feng Chen 《Open Journal of Radiology》 2024年第1期14-23,共10页
Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions... Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBS<sub>x</sub>, and along the direction parallel to the forearm, TBS<sub>y</sub>, were calculated respectively. The statistics of TBS<sub>x</sub> and TBS<sub>y</sub> were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBS<sub>y</sub> to TBS<sub>x</sub> and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBS<sub>x</sub> and TBS<sub>y</sub> was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age. 展开更多
关键词 ANISOTROPY Trabecular Bone Score Bone Mineral Density Ultra-Distal radius Digital X-Ray Image
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Hemiarthroplasty for irreparable distal radius fractures in the elderly:A comprehensive review
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作者 Adriano Cannella Ludovico Caruso +4 位作者 Giulia Maria Sassara Giuseppe Taccardo Marco Passiatore Marina Marescalchi Rocco De Vitis 《World Journal of Orthopedics》 2024年第6期578-584,共7页
BACKGROUND Elderly patients maintaining functional independence can now be candidates for primary wrist hemiarthroplasty to manage acute irreparable distal radius fractures(DRFs).However,further investigation with lon... BACKGROUND Elderly patients maintaining functional independence can now be candidates for primary wrist hemiarthroplasty to manage acute irreparable distal radius fractures(DRFs).However,further investigation with long-term follow-up is required to validate these initial findings.AIM To review the literature on the outcomes of distal radius hemiarthroplasty with available implants to assess its viability as a treatment option.METHODS A comprehensive review of the literature was conducted using electronic databases,including PubMed,Medline,and Scopus.The search terms employed were"distal radius fracture","hemiarthroplasty","wrist arthroplasty",and related terminology.The search was restricted to articles published in English from 1980 until June 2023.Inclusion criteria encompassed cases or case series of DRF treated with hemiarthroplasty,providing clinical or radiographic outcomes,and published in peer-reviewed journals.RESULTS A total of 2508 articles from PubMed and 883 from Scopus were identified initially.Following screening and removal of duplicates,13 articles met the inclusion criteria.These articles,predominantly clinical retrospective studies,provided insights into hemiarthroplasty outcomes,including functional improvements and complications.Hemiarthroplasty was a treatment option for complex DRF,particularly those cases with severe comminution,intraarticular involvement,or severe osteoporosis.Functional outcomes demonstrated improvements in pain relief,wrist mobility,and grip strength,with variability across studies.Complications included implant loosening,infection,nerve injury,and stiffness,with varying incidence rates influenced by surgical techniques and implant choice.Long-term outcomes were inadequately documented,warranting further research.CONCLUSION Hemiarthroplasty is a promising treatment for irreparable DRF in the elderly.Long-term outcomes and complications require further study. 展开更多
关键词 Irreparable distal radius fracture HEMIARTHROPLASTY OSTEOPOROSIS Wrist prosthesis ELDERLY
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The extending length calculation of hydraulic drive non-metallic completion screen pipe running into ultra-short radius horizontal well
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作者 BI Yansen XIAN Baoan +1 位作者 SHI Xiaolei GAO Deli 《Petroleum Exploration and Development》 CSCD 2022年第4期942-954,共13页
Focusing on the extending length restriction of the completion screen pipe resistance running into ultra-short radius horizontal well,this paper proposed technology of hydraulic drive completion tubular string running... Focusing on the extending length restriction of the completion screen pipe resistance running into ultra-short radius horizontal well,this paper proposed technology of hydraulic drive completion tubular string running into ultra-short radius horizontal well.Innovative hydraulic drive tools and string structure are designed,which are composed of guide tubing,hydraulic drive tubing and non-metallic completion screen pipe from inside to outside.A novel mechanical-hydraulic coupling model is established.Based on the wellbore structure of an ultra-short radius horizontal well for deep coalbed methane,the numerical calculations of force and hydraulic load on tubular strings were accomplished by the mechanical-hydraulic coupling model.The results show that the extending length of completion tubular string with the hydraulic drive is 17 times that of conventional completion technology under the same conditions.The multi-factor orthogonal design is adopted to analyze the numerical calculations,and the results show that the extending length of the completion tubular string is mainly affected by the completion tubular string structure and the friction coefficient between the non-metallic composite continuous screen pipe and the wellbore.Two series of hydraulic drive completion tubular string structures suitable for ultra-short radius horizontal wells under different conditions are optimized,with the extending limits of 381 m and 655 m,respectively.These researches will provide theoretical guidance for design and control of hydraulic drive non-metallic composite continuous completion screen pipe running into ultra-short radius horizontal wells. 展开更多
关键词 ultra-short radius horizontal well screen pipe completion hydraulic drive technology non-metallic composite continuous screen pipe screen pipe extending length
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RADIUS服务器防重播攻击策略研究
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作者 高进坤 《福建电脑》 2024年第4期49-52,共4页
为提高网络信息访问的安全性,有意识减少用户在访问RADIUS服务器时可能存在被重播攻击的风险,本文探讨了RADIUS网络服务器简单有效的防御策略。通过用黑名单机制加固RADIUS服务器,来防范对RADIUS服务器的重播攻击。该策略可有效减小恶... 为提高网络信息访问的安全性,有意识减少用户在访问RADIUS服务器时可能存在被重播攻击的风险,本文探讨了RADIUS网络服务器简单有效的防御策略。通过用黑名单机制加固RADIUS服务器,来防范对RADIUS服务器的重播攻击。该策略可有效减小恶意数据的攻击的影响,提高RADIUS服务器的安全性和健壮性。 展开更多
关键词 radius协议 重播攻击 黑名单 网络安全
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Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems
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作者 Chein-Shan Liu Chung-Lun Kuo Chih-Wen Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3189-3208,共20页
To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection techniq... To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit function.We can quickly determine the optimal values of the parameters within a preferred rage using the golden section search algorithm.The novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical examples.Moreover,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being ill-posed.The optimal MQ-RBF is extremely accurate.We further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11). 展开更多
关键词 Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method
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Spatial Distribution Characteristics and Coverage Rate of Commercial Facilities in 15-minute Radius Livelihood Service Circles of Chunshu Street
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作者 HAN Qiqi YANG Kaitai 《Journal of Landscape Research》 2024年第1期17-21,共5页
Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,... Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,Xicheng District of Beijing served as a national pilot of the 15-minute radius livelihood service circle.Based on the data of POI,urban walking network and building outline,this paper studies the coverage of commercial service facilities in the 15-minute radius livelihood service circle of Chunshu Street by using kernel density analysis and urban network analysis tools.The research shows that the commercial facilities are concentrated in Zhuangsheng Square and Dazhalan commercial district.There are large gaps in housekeeping and couriers logistics facilities,which need to be further improved. 展开更多
关键词 Chunshu Street 15-minute radius livelihood service circle POI Historic urban areas Community business
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基于RADIUS和数字证书的无线网络接入认证技术研究
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作者 王润园 葛声 荆浩 《通信电源技术》 2024年第3期140-142,共3页
随着网络技术的发展,无线网络接入认证技术的应用越来越广泛。通过远程认证拨入用户服务(Remote Authentication Dial In User Service,RADIUS)和数字证书配合使用,可以实现较为安全完善的无线网络接入认证。介绍RADIUS和数字证书的相... 随着网络技术的发展,无线网络接入认证技术的应用越来越广泛。通过远程认证拨入用户服务(Remote Authentication Dial In User Service,RADIUS)和数字证书配合使用,可以实现较为安全完善的无线网络接入认证。介绍RADIUS和数字证书的相关概念,概述使用RADIUS和数字证书进行无线网络接入时的网络拓扑与接入认证过程,给出RADIUS代理服务器、认证服务器以及数字证书的配置方法同时,给出验证该无线网络接入认证技术的方法,也是Linux客户端进行网络接入认证的方法。通过搭建RADIUS网络接入环境,使用数字证书作为认证凭证,实现客户端对无线网络的接入认证。 展开更多
关键词 远程认证拨入用户服务(radius) 数字证书 无线网络接入认证技术
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RADIUS在802.1x中的应用 被引量:18
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作者 黄永锋 王滨 许晓东 《计算机工程与设计》 CSCD 北大核心 2006年第5期798-801,共4页
在802.1x中使用RADIUS认证,可以为宽带网络提供一种安全的认证、授权、计费方案,而用户的统一认证、上网时限控制和同一账户的多人使用问题并没有被RADIUS本身所解决,使用目录树统一存储用户信息,并通过Schema扩展RadiusSi-multaneous和... 在802.1x中使用RADIUS认证,可以为宽带网络提供一种安全的认证、授权、计费方案,而用户的统一认证、上网时限控制和同一账户的多人使用问题并没有被RADIUS本身所解决,使用目录树统一存储用户信息,并通过Schema扩展RadiusSi-multaneous和RadiusLoginTime属性以及改进认证流程可以解决上述问题。 展开更多
关键词 802.1x NAS radius EAP 轻量级目录访问协议 单点登录
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RADIUS服务器安全性分析及其改进 被引量:8
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作者 张琪 喻占武 李锐 《计算机工程》 CAS CSCD 北大核心 2007年第5期146-148,共3页
对RADIUS协议所采用的通过共享密钥、认证码等实现的安全措施进行分析,指出其仍然存在的多方面的安全漏洞。在实现中针对RADIUS协议的安全漏洞采取可能的改进措施,在一定程度上弥补了RADIUS协议安全性上的不足,使实现的RADIUS服务器端... 对RADIUS协议所采用的通过共享密钥、认证码等实现的安全措施进行分析,指出其仍然存在的多方面的安全漏洞。在实现中针对RADIUS协议的安全漏洞采取可能的改进措施,在一定程度上弥补了RADIUS协议安全性上的不足,使实现的RADIUS服务器端更好地满足了实际应用的需要。 展开更多
关键词 radius 共享密钥 认证码 安全性
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802.1x标准和Radius协议的扩展应用研究 被引量:15
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作者 蒋海锋 苗放 《计算机应用》 CSCD 北大核心 2003年第11期88-90,共3页
首先介绍了802.1x标准和RADIUS协议的基本概念和原理,并对802.1x标准和RADIUS协议在宽带网络和无线网络中的应用做了分析,结合实际应用的需求,指出了802.1x标准和RADIUS协议在实际应用中的不足与缺陷,分析其难以推广的原因,提出了实现... 首先介绍了802.1x标准和RADIUS协议的基本概念和原理,并对802.1x标准和RADIUS协议在宽带网络和无线网络中的应用做了分析,结合实际应用的需求,指出了802.1x标准和RADIUS协议在实际应用中的不足与缺陷,分析其难以推广的原因,提出了实现扩展应用的设计方案和具体实现方法,以符合宽带环境下认证和计费的实际应用需求。 展开更多
关键词 802.1x radius 认证 计费 宽带网络
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一种基于Linux的Radius客户端的设计与实现 被引量:6
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作者 赵宇 刘刚 杨宗凯 《计算机工程》 CAS CSCD 北大核心 2003年第15期112-114,共3页
提出了一种基于Linux操作系统的Radius客户端的设计,具有良好的可扩展性并通过并行处理解决了现有的客户端数目增加导致阻塞的问题。基于Red Hat Linux6.2系统加以实现并通过测试达到了良好的效果。
关键词 radius 验证 授权 计费 网络接入服务器
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RADIUS在端口认证中的应用及其实现 被引量:4
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作者 张敬伟 周娅 周德新 《计算机应用》 CSCD 北大核心 2004年第6期36-38,共3页
端口认证是一种基于物理端口的认证机制,它以物理端口为操控对象,通过在物理端口级对用户施加认证来加强网络安全。RADIUS提供了一种安全有效的认证服务。文中就如何在端口认证中利用RADIUS提供的认证服务,进行安全的认证交换,在一定程... 端口认证是一种基于物理端口的认证机制,它以物理端口为操控对象,通过在物理端口级对用户施加认证来加强网络安全。RADIUS提供了一种安全有效的认证服务。文中就如何在端口认证中利用RADIUS提供的认证服务,进行安全的认证交换,在一定程度上保证网络的安全性进行了探讨,并介绍了RADIUS服务器的实现,分析了RADIUS服务器的安全性。 展开更多
关键词 radius NAS EAP 端口认证
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RADIUS协议在AAA系统中的应用研究 被引量:24
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作者 王军号 陆奎 《计算机技术与发展》 2009年第7期199-202,共4页
RADIUS协议在宽带网络认证授权计费解决方案AAA认证系统中得到了广泛应用。介绍了RADIUS协议的结构特点、报文内容、AAA系统架构和802.1x标准,讨论了RADIUS认证的工作流程,研究了RADIUS协议的认证机制以及在Linux环境下RADIUS服务器的... RADIUS协议在宽带网络认证授权计费解决方案AAA认证系统中得到了广泛应用。介绍了RADIUS协议的结构特点、报文内容、AAA系统架构和802.1x标准,讨论了RADIUS认证的工作流程,研究了RADIUS协议的认证机制以及在Linux环境下RADIUS服务器的配置方法,建立了RADIUS认证服务器的功能模型,分析了RADIUS协议所采取的安全措施以及存在的安全隐患,并对其安全性的进一步完善提出了建议。 展开更多
关键词 radius AAA 802.1x 安全性
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RADIUS协议认证和授权方法及包结构 被引量:11
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作者 张南雨 屈雪莲 《重庆邮电学院学报(自然科学版)》 2001年第3期78-81,共4页
RADIUS(Remote Authentication Dial In User Service)协议是一种基于client/server的拔号认证协议标准,其主要用途是进行身份认证,授权和计费、介绍了RADIUS... RADIUS(Remote Authentication Dial In User Service)协议是一种基于client/server的拔号认证协议标准,其主要用途是进行身份认证,授权和计费、介绍了RADIUS协议在网络接入服务器和认证服务器间进行认证和授权的方法,以及数据包的格式. 展开更多
关键词 radius协议 认证 授权 通信协议 包结构
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RADIUS在远程接入安全认证中的应用 被引量:8
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作者 曹敬 张敬平 《计算机工程与应用》 CSCD 北大核心 2003年第7期134-136,共3页
该文深入分析了在Linux平台下用FreeRadius软件构建远程用户安全认证服务器的原理和RADIUSClient/Server集成配置的实现方法。这种实现方法在笔者承担的基金项目中得到充分的应用,实践证明该方法安全、高效、可行。
关键词 radius 安全认证 Freeradius软件 网络接人服务器 计算机网络
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基于RADIUS协议的网络认证技术研究 被引量:14
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作者 杨建军 贾晨军 冉立新 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2005年第2期234-237,共4页
介绍了远程用户拨号认证(RADIUS)协议的工作原理和使用的安全算法,分析了其安全性和可能存在的安全漏洞,提出了改进的RADIUS协议以增加网络的安全性能.利用该协议建立了提供给运行商用于无线接入网络的网络认证、授权和计费(AAA)系统.... 介绍了远程用户拨号认证(RADIUS)协议的工作原理和使用的安全算法,分析了其安全性和可能存在的安全漏洞,提出了改进的RADIUS协议以增加网络的安全性能.利用该协议建立了提供给运行商用于无线接入网络的网络认证、授权和计费(AAA)系统.该系统不增加协议的通信复杂性,并具有简单和易实现的特点. 展开更多
关键词 radius协议 AAA MD5 网络安全
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