共查询到19条相似文献,搜索用时 187 毫秒
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在集中式/协作式/云计算无线接入网(C-RAN)环境下,结合热点及室内覆盖的长期演进(LTE-Hi)特点,研究导频图案的设计。LTE-Hi要求插入的导频数量比传统的长期演进(LTE)少,又由于其覆盖特点导致小区边界更容易受相邻小区干扰,由此提出一种应用块重复的正交频分多址(BR-OFDMA)和压缩感知信道估计技术的导频图案设计方案。该方案能够探测各相邻小区间的干扰情况,然后根据干扰情况设置BR-OFDMA参数,最后得到导频图案。该方案能明显减少导频数量,在C-RAN的云结构下更适合LTE-Hi相邻小区间的协作配置,能根据干扰情况,在资源消耗与性能之间进行平衡。仿真表明该方案在低信干比环境下仍能表现较好性能,适合在C-RAN与LTE-Hi中应用。 相似文献
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电子支付的安全是电子商务发展和应用的技术保障。作者研究了PKI的体系结构,介绍了基于PKI技术的SSL和SET协议在电子商务中的应用,探讨了基于PKI的电子现金系统实现,提出了一个安全的电子商务支付平台实现方案(SEPP),并对系统架构进行了设计。 相似文献
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本文讨论了密集波分复用(DWDM)技术应用于光纤同轴混合(HFC)网络上的实现方案和网络体系结构,分析了其技术优势以及对系统性能的影响,并且预计将成为未来发展方向的3项关键技术:窄播技术、DWDM在HFC主干网上的多业务传送技术和DWDM应用于HFC网络的上行信道传输。 相似文献
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为了满足人们日益增长的数据流量需求,未来无线通信系统将向更小的小区部署迁移。小蜂窝网络是下一代无线通信系统的关键技术,也是适应未来更加复杂通信环境的有效途径。首先介绍了小蜂窝网络的基本概念,论述了其主要的技术特点和独特的应用优势,分析了其在未来无线通信系统中与其他各种技术可能的融合场景并讨论了对应的特点和存在的难题;然后概述了小蜂窝网络技术发展过程中所面临的主要挑战,分析了目前主要的研究成果和解决方案;最后,结合下一代无线通信的关键技术,如大规模多输入多输出通信、毫米波通信、D2D(Device-to-Device)通信和认知无线电技术等,总结了小蜂窝网络的应用现状并分析了其市场和发展前景。 相似文献
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本文提出一种基于硬件辅助虚拟化技术的恶意软件行为分析系统---THVA。THVA是一个只有6000余行代码,利用了安全虚拟机(SVM)、二级页表(NPT)、外部设备访问保护(EAP)和虚拟机自省等多种虚拟化技术完成的、专门针对恶意软件行为分析的微型VMM。并对系统的虚拟自省性进行了测试,证明了系统的有效性 相似文献
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陈文 《中国商界:上半月》2011,(11):358-359
入侵检测系统,实质上是一个关于如何把对系统具有恶意的行为(或事件)从大量的系统行为中区分出来的分类系统。其核心问题就是如何从己知数据中获得系统的正常行为知识和有关入侵行为的知识(定义、描述系统的行为)。入侵检测系统极其技术是当前网络安全领域研究的重点。本文主要分析和介绍了入侵检测系统的工作流程和部署,并详细介绍了入侵检测系统的分类和入侵检测技术。 相似文献
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针对当前中国制造业企业物流管理存在的问题,提出了企业第三方物流信息系统关键技术及数据挖掘关键算法的研究思路,并对系统技术原理和研究方法做了阐述,该系统的实现将对改善当前企业的物流管理机制、提高决策水平具有十分重要的意义。 相似文献
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在室内多径环境下信号视距传播易受障碍物影响,导致现有的一些室内定位技术对室内环境分布的估计较为困难。时间反转镜(TRM)室内无线定位技术可以有效地减少室内多径效应对信号的影响以及复杂环境造成的延时。但是,若没有信号传输信道的信息,常规TRM技术的定位精度就会大打折扣。针对该问题,给出了一种基于快速行进算法(FMM)的TRM室内无线定位方法。该方法首先利用FMM和同时代数重建算法(SART)迭代更新计算室内环境分布,然后使用估计结果进行TRM定位。仿真结果显示,对于小型规模的目标物体定位误差约为1.84 cm,在未知室内信道信息的仿真环境下,该方法比常规TRM技术的定位精度提高约32.90倍。 相似文献
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Emi Moriuchi 《心理学和销售学》2023,40(1):169-189
Voice conversation agents (VCAs) have moved beyond simple tasks such as information gathering. The integration of VCAs in smart technologies for security has grown in the consumer market. This paper investigates consumers' motivation to use smart technologies controlled by voice conversational agents and how that impacts their perceived hedonic and utilitarian value, which eventually leads to their satisfaction with smart technologies usage. Two cross-sectional studies and a netnography were conducted. The findings showed that the variables measuring technology acceptance mediate the relationship between consumers' motivation and the perceived value of the VCA-controlled smart technologies. Study 1 results show that ease of use and usefulness of the VCA-controlled smart technologies have a more substantial mediating effect between motivation and hedonic value than utilitarian value. For study 2, results show that the mediators had a stronger influence on hedonic and utilitarian values for outdoor voice conversational agent-controlled smart technologies than indoor smart technologies. Study 3 showed that smart technologies have both risks and benefits and depend on whether they are being used for themselves or others. The results suggest that marketers need to consider consumer's emphasis on the products' features including its ease of use and usefulness, and strategically complement it with consumers' prevention and promotion focus for each product. 相似文献
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典型的非正交多址接入技术(Non-orthogonal Multiple Access,NOMA)有稀疏码分(Sparse Code Multiple Access,SCMA)、多用户共享(Multi-user Shared Access,MUSA)、图样分割(Pattern Division Multiple Access,PDMA)等。为了研究这三种典型的NOMA技术与通用滤波多载波复用技术(Universal Filtered Multi-carrier,UFMC)技术结合后的性能,将三种典型的NOMA与UFMC结合,然后分析比较了它们的误码率性能,通过仿真对比得出UFMC-SCMA系统相比其他两种结合系统具有更好的系统性能。为了更进一步验证UFMC-SCMA系统的优点,还将其与热门的OFDM-SCMA系统进行对比。研究结果表明,由于UFMC-SCMA系统具有码本的稀疏性以及近似最优的信息传递算法(Message Passing Algorithm,MPA)检测方案,并采用子频带滤波,有效降低了误码率并提高了频谱效率,因而其具有较好的系统性能。 相似文献
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Gloria Phillips-Wren Sueanne McKniff 《Journal of Organizational Computing & Electronic Commerce》2013,23(2):213-232
Medication errors are causing harm, and even death, to hospital inpatients. These preventable errors occur at the hands of the same individuals who are charged to protect and provide care to patients—health care professionals. While decision support technologies are available to assist health care providers, patients continue to experience incorrect medications, inaccurate doses/rates of medication, duplicate doses, medication interactions, and other medication errors. This article investigates the reasons that health care professionals in hospital environments underutilize medication administration technologies and argues that a fusion view can provide guidance to increase their use. A Fusion Model is developed using the concept of embeddedness, the Technology Acceptance Model, the Task-Technology-Fit Model, and drawing on ethnographic fieldwork conducted at a modern hospital in the United States. The most important findings of this research are: (1) the concept of embeddedness can be used to study and frame fusion of technology in an environment; (2) four constructs (i.e., task characteristics, technology characteristics, individual use behavior, environmental characteristics) are identified and used to describe system characteristics needed to support medication decisions; and (3) guidance is provided for design and evaluation of decision support technologies for medication administration in hospitals. 相似文献
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The goal of this study was to identify and examine the various factors affecting adolescents' body‐tanning behaviours. Gender, body mass index (BMI), sociocultural attitudes towards appearance (SATA) and body satisfaction were examined in order to determine how these variables influence both outdoor sun‐tanning and indoor tanning‐bed use. Self‐administered survey data were collected from 155 adolescent boys and 202 adolescent girls with an average age of 14.3. Multivariate analysis of variance and multiple regression methods were used to analyse the data. Adolescent girls tended to engage in both outdoor and indoor tanning. Overall, adolescents' SATA significantly affected their body‐tanning behaviours. However, BMI and body satisfaction revealed a significant effect only on indoor tanning behaviour. Implications for the design of interventions and overall health promotion towards adolescents are discussed with suggestions for future research. 相似文献