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1.
独立式火灾探测报警器联网系统,可在其保护区域内获取火灾信息,并及时为面临火灾威胁的人员疏散提供保障,为物业及消防救援机构对该类消防安全产品的使用提供有效的监管手段,为消防救援人员在第一时间确定火灾发生部位及灾后火因鉴定提供相关信息支持。随着物联网的发展,近年来此类系统应用较多,但在使用中也存在许多问题,影响了系统的可靠性。本文介绍了保证独立式火灾探测报警器联网系统稳定可靠的关键技术要求与系统平台的相关要求,为独立式火灾探测报警器联网系统的推广、应用提供指导。 相似文献
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Hua Pang 《Telematics and Informatics》2018,35(8):2147-2156
Although WeChat has recently spawned significant resolutions in technology-mediated social contact and interpersonal communication, the research regarding the social and psychological impacts of the newly emerging technology is relatively few. The primary purpose of the current empirical research is to unearth whether and how WeChat interaction could enhance overseas students’ sense of subjective well-being by concentrating on social integration, bridging relationships, and bonding relationships. Using web-based data of 228 Chinese subjects, the obtained results reveal that the time spent on WeChat significantly and directly impacts users’ subjective well-being. Additionally, the findings demonstrate that social integration, bridging relationships, bonding relationships are all significant predictors to subjective well-being. Furthermore, the perceptions of social integration and social capital could play the crucial mediating roles in the connection between WeChat use and the dependent variable of subjective well-being. Therefore, these outcomes may shed light on a more nuanced comprehending of the influence of the new social media interaction on sojourner’s social adaption and overall life quality in the digital age. 相似文献
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The emerging software‐defined networking (SDN) paradigm introduces new opportunities to improve network performance due to the flexibility and programmability provided by a logically centralized element named controller. However, a rapid adoption of the full SDN architecture is difficult in the short term due to economic and technical reasons. This paper faces the SDN nodes replacement problem during the transition from traditional IP networks to fully deployed SDN networks. Six different replacement methods are proposed to select the most appropriate set of traditional IP nodes to be upgraded to SDN‐enabled switches at a particular transition stage. To show the effectiveness of the proposed methods, they have been applied on an optimization problem currently studied by the research community: the power consumption problem. An integer linear programming formulation is presented to solve it and a genetic algorithm is evaluated through simulations on realistic network topologies. Results highlight that energy‐efficiency in hybrid IP/SDN networks can be significantly improved by only replacing a reduced number of IP nodes. 相似文献
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In view of the fact that existing security service path optimization methods lack a comprehensive consideration of the specific security requirements and the underlying resource status, a dynamic construction mechanism of security service path based on the heuristic breadth first search algorithm is proposed. First, the overall structure of the dynamic construction of the security service path based on the software-defined networking is given, and the integer linear programming is introduced to model this problem. Second, a model solving algorithm is proposed, which mainly adopts the "first select after search" method to solve the security service path construction problem which considers both the specific security needs and the underlying resource status. Finally, simulation results show that the proposed construction mechanism is better than the compared method in terms of the performance index. 相似文献
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ABSTRACTSocial networking technology has the potential to transform how organizations communicate, cooperate, and connect with key stakeholders. Our research explores how social networking technologies are deployed within organizations and how the use of these technologies is related to effectiveness in organizational communication and promotion. We also identify the facilitating factors and constraints around the use of social networking tools for communication. To examine these questions, we conducted interviews with 131 senior level executives across a broad range of organizations and employed both quantitative and qualitative methods of analysis. The executives were asked to rate numerically and then discuss in narrative form a series of questions about IT strategy and issues affecting social networking in their organization. We find important differences both in the types of tools used as well as how they are used and discuss the implications of our findings for companies seeking to more effectively harness social networking technologies. 相似文献
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互联网目前已经发展为一个由实时视频和视频点播等内容分发服务主导的网络.传统IP网络对于视频分发类任务的支持存在组播的部署复杂且开销大,不能有效利用多路径获取内容、对移动性的支持差和难以同时满足可靠性以及低延时需求等问题.命名数据网络(named data networking,NDN)作为新型的下一代互联网体系结构,支持网络内缓存和多路径传输,而且由消费者驱动的传输模式使其天然地支持消费者端移动性.以上特点使NDN具有高效传输视频内容的潜力.首先介绍了视频传输和NDN的基础背景,然后阐述了一些利用NDN中优势实现视频传输的设计方案.通过对已有方案的总结与比较,最后指出了在NDN中传输视频所面临的挑战. 相似文献
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针对信息中心移动自组网场景中节点间间歇连接和网内泛在缓存的特点,提出一种基于门限秘密共享机制的数据访问控制机制.通过构建辅助密钥块,降低了消费者解密的开销和网络节点的存储资源消耗.同时,通过引入双变量单向函数,保障了消费者子秘密份额的唯一性,减少了消费者侧秘密份额管理所带来的空间开销.仿真和理论分析结果表明,该机制显著降低了消费者侧的解密开销,良好地适应了信息中心移动自组织网络场景. 相似文献
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为了纪念长江科学院建院70周年,对《长江科学院院报》近10 a来的稿源与载文量、影响因子、作者群结构、基金论文比、学科分析、编委会作用、优质稿源、论文学术不端、新媒体融合、编辑队伍建设、取得的成绩等进行梳理与分析。结果表明:近10 a来期刊发展变化较大,来稿量和发文量分别增加了191%和41%;期刊复合被引频次和期刊影响因子分别提高了146%和74%;期刊其他各项指标也呈稳步提升趋势。通过分析,梳理了期刊的发展历程,旨在进一步提高办刊质量,更好地为推进水利科技进步、促进社会经济发展服务。 相似文献
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传统的流量工程策略的研究大多集中在构建和求解数学模型方面,其计算复杂度过高,为此,提出了一种经验驱动的基于多智能体强化学习的流量分配算法.该算法无需求解复杂数学模型即可在预计算的路径上进行有效的流量分配,从而高效且充分地利用网络资源.算法在软件定义网络控制器上进行集中训练,且在训练完成后再接入交换机或者路由器上分布式执行,同时也避免和控制器的频繁交互.实验结果表明,相对于最短路径和等价多路径算法,新算法有效减少了网络的端到端时延,并且增大了网络吞吐量. 相似文献