NNT: Nearest Neighbour Trapezoid Algorithm for IoT WLAN Smart Indoor Localization Leveraging RSSI Height Estimation

Indoor localization as a technique for assisting, or replacing outdoor satellite and cell tower localization systems, has taken a toll in the recent Internet of Things (IoT) era. This IoT drive has prompted increased research towards indoor localization, where fingerprinting, radio mapping as a cost-effective and efficient scheme, is emerging as the best enterprise entrepreneurs choose. However, indoor complex environments comprise of trackable devices (TD) at various heights, such as child trackers, dog tags, TD on the table, TD’s in the pockets, and situations such as pedestrians talking on the phone: that is at the height of the ear, amongst others. This paper first investigates and analyses “experimentally” the impact of received signal strength indicator (RSSI) fingerprinting height to construct radio maps for indoor localization. Secondly, it proposes the novel trapezoid path loss model for RSSI estimation and finally the nearest neighbour trapezoid (NNT) algorithm for IoT smart indoor localization leveraging and mitigating the impact of height considered during the offline signal fingerprinting. We further propose approximately 1 meter above the flooring of the target space as the effective fingerprinting height for indoor localization approaches.

Africa, China, and the Global South Novel: In Koli Jean Bofane’s Congo Inc.

The People’s Republic of China’s (PRC) presence in Africa has fundamentally changed globalization patterns. Most scholarship interrogates whether the Chinese presence is either a “new colonialism” or a “win-win” for development by focusing on economic or social scientific factors. In contrast, this article examines China as a trope in Congo Inc. (2014) by In Koli Jean Bofane. Congo Inc. is one of the first African novels to take the Africa-China relationship as central theme, depicting how Congolese actors negotiate the PRC’s presence in the Democratic Republic of the Congo. The article examines the unexpected partnership of a trickster, Isookanga, and a stranded Chinese national, Zhang Xia, analyzing their partnership according to the relationship between time and globalization. The argument uses the concept of the postcolony’s durées to demonstrate how the narrative creates a global South temporality, which differentiates Africa-China patterns of globalization from previous instantiations. These durées include Isookanga’s digital consciousness enabled by a PRC-built cell tower; allusions to Chinese history; and Isookanga and Zhang Xia’s collaboration on Eau Pire Suisse. In sum Congo Inc.’s innovative temporality, embodied by the term mondialiste, signals a shift in type of postcolonial narrative toward the global South novel.

MODELLING A CELL TOWER USING SFM: AUTOMATED DETECTION OF STRUCTURAL ELEMENTS FROM SKELETON EXTRACTION ON A POINT CLOUD

The surveying and management of telecommunication towers poses a series of engineering challenges. Not only they must be regularly inspected for the purpose of checking for issues that require maintenance interventions, but they are often sub-let by their owners to communication companies, requiring a survey of the many (several thousand per company) installed appliances to check that they respect the established contracts. This requires a surveying methodology that is fast and possibly automated. Photogrammetric techniques using UAV-mounted cameras seem to offer a solution that is both suitable and economical. Our research team was asked to evaluate whether, from the information acquired by small drones it was possible to obtain geometric information on the structure, with what degree of accuracy and what level of detail. The workflow of this process is naturally articulated in three steps: the acquisition, the construction of the point cloud, and the extraction of geometries. The case study is a tower carrying antennas owned by several operators and placed in the industrial district of Cagliari. The article examines the problems found in modelling such structures using point clouds derived from the Structure-from-Motion technique, in order to obtain a model of nodes and beams suitable for the reconstruction of the structure’s geometric elements, and possibly for a finite elements analysis or for populating GIS and BIM, either automatically or with minimal user intervention. In order to achieve this, we have used voxelization and skeleton extraction algorithms to obtain a 3D graph of the structure. The analysis of the results was carried out by varying the parameters relating to the voxel size, which defines the resolution, and the density of the points contained inside each voxel.