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Framework to Model User Request Access Patterns in the World Wide Web
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作者 Richard Hurley Robert Sturgeon 《Journal of Software Engineering and Applications》 2024年第2期69-88,共20页
In this paper, we present a novel approach to model user request patterns in the World Wide Web. Instead of focusing on the user traffic for web pages, we capture the user interaction at the object level of the web pa... In this paper, we present a novel approach to model user request patterns in the World Wide Web. Instead of focusing on the user traffic for web pages, we capture the user interaction at the object level of the web pages. Our framework model consists of three sub-models: one for user file access, one for web pages, and one for storage servers. Web pages are assumed to consist of different types and sizes of objects, which are characterized using several categories: articles, media, and mosaics. The model is implemented with a discrete event simulation and then used to investigate the performance of our system over a variety of parameters in our model. Our performance measure of choice is mean response time and by varying the composition of web pages through our categories, we find that our framework model is able to capture a wide range of conditions that serve as a basis for generating a variety of user request patterns. In addition, we are able to establish a set of parameters that can be used as base cases. One of the goals of this research is for the framework model to be general enough that the parameters can be varied such that it can serve as input for investigating other distributed applications that require the generation of user request access patterns. 展开更多
关键词 Performance Modelling World Wide Web SIMULATION user Request access Patterns FRAMEWORK
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Remote Access Communications Security: Analysis of User Authentication Roles in Organizations 被引量:2
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作者 Ezer Osei Yeboah-Boateng Grace Dzifa Kwabena-Adade 《Journal of Information Security》 2020年第3期161-175,共15页
Remote access is a means of accessing resources outside one’s immediate physical location. This has made employee mobility more effective and productive for most organizations. Remote access can be achieved via vario... Remote access is a means of accessing resources outside one’s immediate physical location. This has made employee mobility more effective and productive for most organizations. Remote access can be achieved via various channels of remote communication, the most common being Virtual Private Networks (VPNs). The demand for remote access is on the rise, especially during the Covid-19 pandemic, and will continue to increase as most organizations are re-structuring to make telecommuting a permanent part of their mode of operation. Employee mobility, while presenting organizations with some advantages, comes with the associated risk of exposing corporate cyber assets to attackers. The remote user and the remote connectivity technology present some vulnerabilities which can be exploited by any threat agent to violate the confidentiality, integrity and availability (CIA) dimensions of these cyber assets. So, how are users and remote devices authenticated? To what extent is the established connection secured? With employee mobility on the rise, it is necessary to analyze the user authentication role since the mobile employee is not under the monitoring radar of the organization, and the environment from which the mobile employee connects may be vulnerable. In this study, an experiment was setup to ascertain the user authentication roles. The experiment showed the process of 2FA in user authentication and it proved to be an effective means of improving user authentication during remote access. This was depicted via the use of what the user has (mobile phone/soft-token) as a second factor in addition to what the user knows, i.e. password. This authentication method overcomes the security weaknesses inherent in single-factor user authentication via the use of password only. However, the results also showed that though 2FA user authentication ensures security, the remote devices could exhibit further vulnerabilities and pose serious risks to the organization. Thus, a varied implementation was recommended to further enhance the security of remote access communication with regards to the remote user authentication. 展开更多
关键词 Remote access Communications Security user Authentication 2FA Virtual Private Network (VPN) TELECOMMUTING Threats VULNERABILITIES
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Factors Influence Hanoians’ Choice of Non-Motorized Transport Mode to Access Bus Stations
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作者 Ngo Trung Phuong Masahiko Kikuchi +1 位作者 Aya Kojima Hisashi Kubota 《Journal of Transportation Technologies》 2024年第3期372-389,共18页
Hanoi’s rapid urbanization has led to a surge in private vehicle ownership, particularly motorcycles, amidst inadequate public transportation infrastructure. Despite government efforts, many still prefer motorized tr... Hanoi’s rapid urbanization has led to a surge in private vehicle ownership, particularly motorcycles, amidst inadequate public transportation infrastructure. Despite government efforts, many still prefer motorized transport, citing mobility and safety concerns, exacerbated by insufficient pedestrian infrastructure. This study examines the motivations behind this reliance on motorized vehicles, particularly motorcycles, in Hanoi. Findings reveal safety and convenience as primary factors driving motorized transport use, especially for accessing bus stations. Economic incentives could promote non-motorized travel and public transport adoption. Policy implications highlight the importance of addressing economic factors and improving access infrastructure to manage motorized vehicle reliance and foster sustainable urban mobility in Hanoi. 展开更多
关键词 access Mode Choice Non-Motorized Vehicles Motorized Vehicles Bus user Urban Transport Behavior
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ACCESS中利用宏实现系统的多用户分角色登录 被引量:1
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作者 姚一红 《办公自动化(综合月刊)》 2009年第5期52-53,共2页
用户标识与鉴别(Identification&Authentication)是系统为数据库提供的最外层的安全保护措施。一般来讲,用户标识与鉴别(系统登录)的实现需要计算机专业人员用编程语言来实现,考虑到ACCESS可以直接面向数据库的最终用户,而数据库最... 用户标识与鉴别(Identification&Authentication)是系统为数据库提供的最外层的安全保护措施。一般来讲,用户标识与鉴别(系统登录)的实现需要计算机专业人员用编程语言来实现,考虑到ACCESS可以直接面向数据库的最终用户,而数据库最终用户往往并非计算机的专业人员,本文介绍了一种在ACCESS数据库中不用编码而用宏对象实现的系统多用户分角色登录方法。 展开更多
关键词 access 多用户 分角色 登录
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Access XP数据库的安全性研究 被引量:2
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作者 李海燕 《中国安全科学学报》 CAS CSCD 2005年第5期67-70,共4页
在信息化时代来临、Internet高速发展的今天,信息资源的经济和社会价值越来越明显,而数据库系统所管理、存储的数据已成为各个部门宝贵的信息资源,所以其安全保密性是目前所迫切需要解决的问题。笔者从数据库的安全性、保密性的角度,详... 在信息化时代来临、Internet高速发展的今天,信息资源的经济和社会价值越来越明显,而数据库系统所管理、存储的数据已成为各个部门宝贵的信息资源,所以其安全保密性是目前所迫切需要解决的问题。笔者从数据库的安全性、保密性的角度,详细地阐述了MicrosoftAccessXP数据库的安全机制;探讨了实现MicrosoftAccessXP数据库不同保护级别的各种方法;还讨论了共享级安全性和用户级安全性问题。 展开更多
关键词 access 安全性研究 XP MICROSOFT Internet 信息资源 信息化时代 数据库系统 安全保密性 安全性问题 社会价值 安全机制 保护级别 用户级 共享
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用VB6.0设计Access数据库的用户级安全管理模块
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作者 罗彬 刘独玉 《渝州大学学报》 2001年第1期15-19,共5页
在分析了Access数据库安全的重要性的基础上 ,用VB6 .0开发了Access数据库的用户级安全管理模块 ,并详细地介绍了其实现的基本原理、主要过程和核心代码。
关键词 access数据库 用户级 安全管理 VB6.0 数据访问对象模型 密码 权限控制
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基于ACCESS的用户信息系统框架设计与实现
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作者 高恩勇 谢德银 《沧州师范学院学报》 2010年第3期113-115,126,共4页
现代的用户信息系统框架是在应用系统启动的时候出现"用户登录窗口",用户输入正确的登录信息后,单击"登录"按钮,出现系统主窗口,主窗口采用windos风格,即在主窗口界面中使用菜单栏和工具栏实现应用系统的各项功能... 现代的用户信息系统框架是在应用系统启动的时候出现"用户登录窗口",用户输入正确的登录信息后,单击"登录"按钮,出现系统主窗口,主窗口采用windos风格,即在主窗口界面中使用菜单栏和工具栏实现应用系统的各项功能。讨论了在Access环境下,用户应用系统框架的设计与实现的技术、技巧和方法。对于指导Access初学者,尤其是不会Access VBA编程的人员具有较高的应用参考价值。 展开更多
关键词 用户信息系统框架 MICROSOFT access 宏(Micro) 菜单(menu) 窗体(form)
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ASP+Access的安全性研究 被引量:4
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作者 谌爱文 施荣华 《微电子学与计算机》 CSCD 北大核心 2006年第6期106-108,共3页
随着计算机技术的发展,基于计算机网络的数据库应用系统越来越广泛,其安全保密性成为目前迫切需要解决的问题。为了更好地提高数据库的安全性,文章分析了Access数据库及ASP技术的安全问题,并给出了相应的解决方案。
关键词 access数据库 ASP 用户级安全系统 数据库安全管理
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关于Access2000的安全机制解析 被引量:2
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作者 李川 李中 《西安航空技术高等专科学校学报》 2008年第1期64-65,67,共3页
Microsoft Access 2000数据库作为常用的桌面数据库软件,在中小型的数据库系统中得到了广泛的应用。针对Access 2000安全性能不高,探讨如何设置及提高Access 2000的安全性方法。
关键词 access 2000数据库 安全机制 用户级权限 加密或解密 工作组信息文件
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Research and Realization of the Role-Based System Access Control Management 被引量:1
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作者 蔡红 陈荣耀 令狐佳 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期267-269,共3页
The systematical structure of the role-based access control was analyzed,giving a full description of the definitions of user,user access,and the relation between post role and access. It puts forward a role-based acc... The systematical structure of the role-based access control was analyzed,giving a full description of the definitions of user,user access,and the relation between post role and access. It puts forward a role-based access control management which is relatively independent in the applied system. This management achieves the control on user's access by distribution and cancel of role-play,which is a better solution to the problems of the access control management for the applied system. Besides,a complete scheme for the realization of this access control was provided. 展开更多
关键词 access control user distribution
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ACCESS中数据完整性的实现 被引量:1
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作者 吴险峰 《河北软件职业技术学院学报》 2007年第1期49-51,共3页
本文介绍了三类完整性约束规则和相关策略及其实际意义,重点介绍了在ACCESS数据库的设计阶段,如何利用ACCESS提供的机制来实施三类完整性,并对其进行了简要的评价。
关键词 access 参照完整性 实体完整性 用户完整性
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User Interface for People with Autism Spectrum Disorders 被引量:1
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作者 Nikolay Pavlov 《Journal of Software Engineering and Applications》 2014年第2期128-134,共7页
This paper describes the requirements for building accessible user interface for users with autism spectrum disorders (ASD) and presents the user interface (UI) of Open Book, a reading assistive tool for people with A... This paper describes the requirements for building accessible user interface for users with autism spectrum disorders (ASD) and presents the user interface (UI) of Open Book, a reading assistive tool for people with ASD. The requirements are extracted from both existing research on improving reading comprehension for people with ASD, and from the feedback of users and clinical professionals. The findings are applied in practice to create the user interface of Open Book tool. Key screens of the user interface are presented. It is implied that the features of the UI for people with ASD can be successfully applied to improving overall accessibility of any graphical user interface. 展开更多
关键词 accessIBILITY accessible user Interface userS with AUTISM Spectrum DISORDERS Project FIRST
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下行RIS-NOMA的用户集群方法 被引量:1
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作者 彭艺 吴桐 杨青青 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2024年第1期128-136,共9页
为提高用户分布非均匀的场景下可重构智能表面(RIS)辅助下行非正交多址(NOMA)通信系统的性能,提出了一种分布式RIS辅助下行NOMA的用户聚类方案。首先,采用自适应几何分布(AGD)聚类算法划分用户集群(UCs),从而为各UC匹配RIS。然后,利用... 为提高用户分布非均匀的场景下可重构智能表面(RIS)辅助下行非正交多址(NOMA)通信系统的性能,提出了一种分布式RIS辅助下行NOMA的用户聚类方案。首先,采用自适应几何分布(AGD)聚类算法划分用户集群(UCs),从而为各UC匹配RIS。然后,利用分式规划(FP)方法将非凸最大化频谱效率问题转换为凸优化问题。最后,为UC内用户逐级进行功率分配(PA)与被动波束形成(PB)。仿真结果表明,与谱聚类(SPC)、K均值(K-means)、高斯混合模型(GMM)聚类方案和正交多址(OMA)方案相比,在AGD方案下,功率对频谱效率提升了7%、14%、19%和42%的增益,反射面对频谱效率提升了16%、19%、26%和40%的增益。 展开更多
关键词 可重构智能表面 非正交多址 用户集群 分式规划
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智能反射表面辅助的非正交多址接入系统用户分组、波束赋形与相移的优化 被引量:1
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作者 雷维嘉 于顺洪 +1 位作者 雷宏江 唐宏 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第3期858-866,共9页
该文研究智能反射表面(IRS)辅助的多天线非正交多址接入(NOMA)网络中用户分组、发送波束赋形、相移等的联合优化问题。系统中1个分组分配1个波束并在组内进行连续干扰消除检测。该文提出一种不依赖于发送波束赋形和IRS相移的用户分组配... 该文研究智能反射表面(IRS)辅助的多天线非正交多址接入(NOMA)网络中用户分组、发送波束赋形、相移等的联合优化问题。系统中1个分组分配1个波束并在组内进行连续干扰消除检测。该文提出一种不依赖于发送波束赋形和IRS相移的用户分组配对策略,将用户分组与其他优化分离,显著降低了优化问题求解的难度和计算复杂度。进一步,联合优化基站发送波束赋形、功率分配和IRS相移矩阵,最小化基站的总发送功率。原始优化问题是一个多变量相互耦合的非凸优化问题,利用松弛变量、连续凸逼近、半定松弛、交替迭代优化等方法将原问题转化为凸问题并求解。仿真结果显示,相较于1个用户1个波束的方案,所提方案在基站天线数较少时性能更优,而在天线数较多时也与该对比方案非常接近,但所提方案的优化计算复杂度更低。而对比采用不同分组算法、随机IRS相移方案、最大比发射方案,以及无IRS的方案,所提方案的性能始终更优。 展开更多
关键词 智能反射表面 非正交多址接入 用户分组 波束赋形
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Qualitative System Dynamics as a Tool in Accessible Design
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作者 Anthony S. White 《Journal of Software Engineering and Applications》 2011年第1期69-80,共12页
A description of the Systems Dynamics paradigm is given and the reduced Qualitative System Dynamics (QSD) form explained. A simple example is given to illustrate the diagram construction. The principles of states (lev... A description of the Systems Dynamics paradigm is given and the reduced Qualitative System Dynamics (QSD) form explained. A simple example is given to illustrate the diagram construction. The principles of states (levels), rates and feedback loops are outlined. The QSD method is used to address the problem of accessibility by using human control of automation as an example, and applying the QSD method to evaluate the effects of the researcher and user in the de- sign of an accessible artefact. This simple automation model illustrates what can be found out from such a picture, in this indicating how the feedback from users has an influence on the time to deliver such designs. 展开更多
关键词 Qualitative System Dynamics COMPUTER Interaction accessIBILITY user FEEDBACK SOFTWARE Design
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Research on User Pairing Techniques Based on NOMA in Cognitive Radio Networks
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作者 Yongming Huang Xiaoli He Yuxin Du 《Journal of Computer and Communications》 2023年第3期131-145,共15页
This paper outlined a Non-Orthogonal Multiple Access (NOMA) grouping transmission scheme for cognitive radio networks. To address the problems of small channel gain difference of the middle part users caused by the tr... This paper outlined a Non-Orthogonal Multiple Access (NOMA) grouping transmission scheme for cognitive radio networks. To address the problems of small channel gain difference of the middle part users caused by the traditional far-near pairing algorithm, and the low transmission rate of the traditional Orthogonal Multiple Access (OMA) transmission, a joint pairing algorithm was proposed, which provided multiple pairing schemes according to the actual scene. Firstly, the secondary users were sorted according to their channel gain, and then different secondary user groups were divided, and the far-near pairing combined with (Uniform Channel Gain Difference (UCGD) algorithm was used to group the secondary users. After completing the user pairing, the power allocation problem was solved. Finally, the simulation data results showed that the proposed algorithm can effectively improve the system transmission rate. 展开更多
关键词 Cognitive Radio Non-Orthogonal Multiple access user Grouping Power Allocation
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A General Attribute and Rule Based Role-Based Access Control Model
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作者 朱一群 李建华 张全海 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第6期719-724,共6页
Growing numbers of users and many access control policies which involve many different resource attributes in service-oriented environments bring various problems in protecting resource.This paper analyzes the relatio... Growing numbers of users and many access control policies which involve many different resource attributes in service-oriented environments bring various problems in protecting resource.This paper analyzes the relationships of resource attributes to user attributes in all policies, and propose a general attribute and rule based role-based access control(GAR-RBAC) model to meet the security needs. The model can dynamically assign users to roles via rules to meet the need of growing numbers of users. These rules use different attribute expression and permission as a part of authorization constraints, and are defined by analyzing relations of resource attributes to user attributes in many access policies that are defined by the enterprise. The model is a general access control model, and can support many access control policies, and also can be used to wider application for service. The paper also describes how to use the GAR-RBAC model in Web service environments. 展开更多
关键词 ATTRIBUTE RULE user-role ASSIGNMENT ROLE-BASED access control(RBAC) access policy
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An Efficient Scheduling Scheme for Fronthaul Load Reduction in Fog Radio Access Networks
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作者 Sovit Bhandari Hong Ping Zhao Hoon Kim 《China Communications》 SCIE CSCD 2019年第11期146-153,共8页
Fog radio access network(F-RAN) is one of the key technology that brings cloud computing benefit to the future of wireless communications for handling massive access and high volume of data traffic. The high fronthaul... Fog radio access network(F-RAN) is one of the key technology that brings cloud computing benefit to the future of wireless communications for handling massive access and high volume of data traffic. The high fronthaul burden of a typical cellular system can be partially diminished by utilizing the storage and signal processing capabilities of the F-RANs, which is still not desirable as user throughput requirement is in the increasing trend with the increment of the internet of things(IoT) devices. This paper proposes an efficient scheduling scheme that minimizes the fronthaul load of F-RAN system optimally to improve user experience, and minimize latency. The scheduling scheme is modeled in a way that the scheduler which provides the lower fronthaul load while fulfilling the minimum user throughput requirement is selected for the data transmission process. Simulation results in terms of user selection fairness, outage probability, and fronthaul load for a different portion of user equipments(UEs) contents in fog access point(F-AP) are shown and compared with the most common scheduling scheme such as round robin(RR) scheme to validate the proposed method. 展开更多
关键词 FOG RADIO access networks FOG access POINTS fronthaul load user THROUGHPUT
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档案工作数字化转型场域下法规体系的完善理路——以《中华人民共和国档案法实施条例》为分析视角 被引量:2
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作者 陈永生 包惠敏 邓文慧 《档案管理》 北大核心 2024年第2期58-62,共5页
档案工作数字化转型是适应数字中国重要发展战略、提高档案治理效能、实现档案事业高质量发展的必然路径。《中华人民共和国档案法实施条例》在提高档案法规体系立法质量、推动档案法规体系科学构建,进而完善新时代国家档案法规体系方... 档案工作数字化转型是适应数字中国重要发展战略、提高档案治理效能、实现档案事业高质量发展的必然路径。《中华人民共和国档案法实施条例》在提高档案法规体系立法质量、推动档案法规体系科学构建,进而完善新时代国家档案法规体系方面具有重要作用。基于此,《中华人民共和国档案法实施条例》从顶层设计、数字资源建设、数字基础设施建设、利用服务四个层面推动档案工作实现数字化转型,但对于相关规定的具体落实仍存在进一步精细化和优化的空间。 展开更多
关键词 档案法规体系 档案信息化 数字化转型 档案法实施条例 数字资源 数据治理 可及性 便利性
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The Impact of User and Traffic Models on the Design of the Communications Network in the Smart Grid
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作者 A. T. Burrell Fernando Mancilla-David P. Papantoni-Kazakos 《International Journal of Communications, Network and System Sciences》 2014年第3期90-99,共10页
A critical component of the smart grid (SG) infrastructure is the embedded communications network, where an important objective of the latter is the expansion of its throughput, in conjunction with the satisfaction of... A critical component of the smart grid (SG) infrastructure is the embedded communications network, where an important objective of the latter is the expansion of its throughput, in conjunction with the satisfaction of specified latency and accuracy requirements. For the effective design of the communications network, the user and traffic profiles, such as known-user vs. unknown-user populations and bursty vs. non-bursty data traffics, must be carefully considered and subsequently modeled. This paper relates user and traffic models to the deployment of effective multiple access transmission algorithms in the communications network of the SG. 展开更多
关键词 Smart Grid COMMUNICATIONS user MODELS TRAFFIC MODELS MATCHING Multiple access COMMUNICATIONS Algorithms
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