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991.
992.
《Journal of Location Based Services》2013,7(1):16-32
The current success of ephemeral communication apps such as Snapchat points to the growing awareness among users about online ‘biographic mining’ through information technology by advertisers, companies and government agencies. Based on the literature, we argue that location-based services (LBS) can be the answer to preserving privacy, on the condition that they target trusted communities of anonymous users and that the communication is transient. The paper describes in three steps the development of an app fulfilling these conditions. From the interdisciplinary exchange between digital anthropologists, GIScientists and ICT engineers resulted Zone-it, a virtual notice board for self-zoning, permitting the user to start location-based interactions under certain categories. We present the results of a user survey that determined the app's functionalities. The functionalities offer a way for LBS to invert the purpose of social media such as Facebook by shifting attention from person-based to goal-oriented communication. The paper discusses why this move away from ‘faces’ to ‘places’ meets the purpose of community-building, rather than jeopardising it. 相似文献
993.
994.
针对星间光通信系统的要求,采用一种新型的半导体激光耦合方案,用前后正交的非球面柱面透镜准直半导体激光束,再经渐变折射率(graduated refractive index,GR IN)自聚焦透镜聚焦,把光束耦合入单模光纤。就此耦合单元,对耦合效率随半导体激光器的位置偏离及角度偏移进行了研究,在光纤尾纤处测得了输出功率随驱动电流的变化关系,单模运行的半导体激光二极管经耦合后的出纤功率可以达到80mW。结果表明,耦合效率随位置偏离及角度偏移的变化灵敏度都不高,这可以满足星间光通信的要求。 相似文献
995.
赵媛 《南京工业职业技术学院学报》2006,6(2):61-63
介绍了一种采用无线传输技术和LED大屏幕显示技术相结合,利用无线收发的方式来更新LED大屏幕显示的信息的实现方法。 相似文献
996.
Eliseo Eugenin Enrico Camporesi Camillo Peracchia 《International journal of molecular sciences》2022,23(11)
The history of direct cell-cell communication has evolved in several small steps. First discovered in the 1930s in invertebrate nervous systems, it was thought at first to be an exception to the “cell theory”, restricted to invertebrates. Surprisingly, however, in the 1950s, electrical cell-cell communication was also reported in vertebrates. Once more, it was thought to be an exception restricted to excitable cells. In contrast, in the mid-1960s, two startling publications proved that virtually all cells freely exchange small neutral and charged molecules. Soon after, cell-cell communication by gap junction channels was reported. While gap junctions are the major means of cell-cell communication, in the early 1980s, evidence surfaced that some cells might also communicate via membrane pores. Questions were raised about the possible artifactual nature of the pores. However, early in this century, we learned that communication via membrane pores exists and plays a major role in medicine, as the structures involved, “tunneling nanotubes”, can rescue diseased cells by directly transferring healthy mitochondria into compromised cells and tissues. On the other hand, pathogens/cancer could also use these communication systems to amplify pathogenesis. Here, we describe the evolution of the discovery of these new communication systems and the potential therapeutic impact on several uncurable diseases. 相似文献
997.
目前移动通信业务在我国的发展呈上升趋势,我国的人口基数较大,相关的用户数量较多,这在一定程度上导致相关的数据量十分庞大。传统的通信网络规划已不适用于当前的通信需求,所以加强大数据在通信网络规划中的应用十分重要。基于此,本文探讨了通信网络规划的重要意义和发展现状,分析了大数据在通信网络规划中的作用以及面临的问题,提出了大数据在通信网络规划中的应用措施。 相似文献
998.
999.
编码电缆定位技术和无线扩频通信技术在焦炉四大车自动化系统中的应用 总被引:1,自引:0,他引:1
阐述攀钢煤化工厂新1#、2#焦炉四大车自动化系统应用情况,并对编码电缆定位技术和无线扩频通信技术进行了分析与论述。 相似文献
1000.
Zhengyuan Xu Weijie Liu Zhaocheng Wang Lajos Hanzo 《Digital Communications & Networks》2021,7(4):605-614
With the rapid deployment of Next-Generation Networks (NGN), the research community has initiated discussions on an entirely new suite of optical enabling techniques. To pave the way for the development of future wireless networks, this article aims to unify the existing infrared, visible light, and ultraviolet subbands while also exploring the potential of the Petahertz (PHz) band to support extremely bandwidth-thirsty telepresence style applications. Our focus is on the emerging Petahertz Communication (PetaCom) framework, scenario-dependent propagation channels, modulation schemes, system performance, multiple access techniques, and networking. We conclude with a range of PetaCom challenges and open research issues. 相似文献