This paper proposes a new access link (AL) and backhaul link (BL) resource management technique for use in 3-dimensional (3D) aerial networks. Increased traffic resulting from the emergence of various applications for unmanned aerial vehicles (UAVs) has resulted in a scarcity of resources. The non-orthogonal shared resource allocation (NSRA) framework proposed here solves the problem of resource scarcity by allocating resources to be shared non-orthogonally between the AL and the BL. In addition, we propose a new selective AL-BL resource sharing algorithm assisted by successive interference cancellation (SIC). We also define the resource sharing allowable zone of the 3D aerial network based on air-to-air channel characteristics. Numerical results show that the proposed algorithm enhances the data rate of the 3D network compared with orthogonal resource allocation.

As the number of docent robots in museums has increased, robot personalization services have become important. A survey-based experiment was conducted to catch the difference in perceptions of personalized service for exhibition visitors. As a result, it was found that the background knowledge of the visitors listening to the explanation had an effect on the perception of the personalized service. The finding gives us a set of design criteria for personalized museum guide robot services.

The grant-free non-orthogonal multiple access (GF-NOMA) system, in which users autonomously transmit uplink data signals without carrying out a complicated random access process, offers significant advantages for increasing the efficiency of resource usage with low signaling overhead. In the proposed GF-NOMA system, since the collision resolution process is omitted and resources are not pre-assigned to users, multiple users may use same resource, without the base station (BS) being able to identify these collided users. In addition, in the absence of the UL synchronization procedure generally performed in the random access process, multiple users' signals are received asynchronously. To solve these problems, we have developed a new transceiver structure for the GF-NOMA system consisting of a secondary preamble and a multiuser-multisymbol (MUMS) detector. The purpose of the secondary preamble is to successfully detect user access and estimate channel information even when no collision resolution process is being performed. The MUMS receiver is then proposed as a way to effectively mitigate the severe interference caused by the asynchronous transmission. Simulation results show that the proposed preamble structure and the receiver structure are superior to the conventional schemes. Furthermore, we show that the GF-NOMA system with the proposed transceiver structure achieves much better performance than other GF-NOMA systems in terms of reliability and successfully detected bits.

Radio frequency identification (RFID) technology that is used to identify objects and users and automatically takes advantage of contextual information such as user's location is expected to become an important and a core technology of ubiquitous infrastructure. This technology has been applied to many applications such as retail and supply chain. At recent, there are an increasing number of researches related to mobile RFID that provides RFID service to user with a reader embedded in the mobile device as the one of RFID applications. However, there are an increasing number of concerns, and even some resistance, related to user tracking and profiling using RFID technology. Therefore, in this paper, we review privacy threats that have been reported in various RFID applications and bring up some additional privacy threats in mobile RFID, impeding the deployment of mobile RFID. And we analyze whether various privacy protecting measures that have been proposed to address privacy problems in RFID can also apply to mobile RFID.