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Öğe Analyzing the Water Budgets of Reservoirs by Using Autonomous Mini Boats(Trans Tech Publications Ltd, 2014) Tuna, Gurkan; Arkoc, Orhan; Potirakis, Stelios M.; Nefzi, BilelThe calculation and estimation of water deposits in both man-made reservoirs and natural reservoirs is very important in several aspects. For surface water reservoirs in hot and dry environments, evaporation is an important factor in their operations since it can cause significant water loss. Typically, hydrologists use different computer models which take into account the effects of evaporation to estimate the water budgets of reservoirs. An important step required for this repetitive process is to calculate the current water budget of a reservoir. In this paper, an autonomous system is proposed aiming to support this step. Unlike the common approaches, the proposed system is fast and accurate, and requires no human effort. In this system, first, an autonomous mini boat follows predefined trajectories at a reservoir and builds a depth map (bathymetric map) of it. Then, an onboard computer calculates the water budget of the reservoir. The proposed system is portable and a single system can periodically serve at several water reservoirs. Field tests in the water reservoir of Kirklareli (Kirklareli dam), Turkey, are in progress.Öğe Unmanned aerial vehicle-aided communications system for disaster recovery(Academic Press Ltd- Elsevier Science Ltd, 2014) Tuna, Gurkan; Nefzi, Bilel; Conte, GianpaoloAfter natural disasters such as earthquakes, floods, hurricanes, tornados and fires, providing emergency management schemes which mainly rely on communications systems is essential for rescue operations. To establish an emergency communications system during unforeseen events such as natural disasters, we propose the use of a team of unmanned aerial vehicles (UAVs). The proposed system is a post-disaster solution and can be used whenever and wherever required. Each UAV in the team has an onboard computer which runs three main subsystems responsible for end-to-end communication, formation control and autonomous navigation. The onboard computer and the low-level controller of the UAV cooperate to accomplish the objective of providing local communications infrastructure. In this study, the subsystems running on each UAV are explained and evaluated by simulation studies and field tests using an autonomous helicopter. While the simulation studies address the efficiency of the end-to-end communication subsystem, the field tests evaluate the accuracy of the navigation subsystem. The results of the field tests and the simulation studies show that the proposed system can be successfully used in case of disasters to establish an emergency communications system. (c) 2013 Elsevier Ltd. All rights reserved.Öğe A Wireless Network of Acoustic Sensors for Environmental Monitoring(Trans Tech Publications Ltd, 2014) Potirakis, Stelios M.; Nefzi, Bilel; Tatlas, N. -A.; Tuna, Gurkan; Rangoussi, M.A distributed microelectronic system for the sound/acoustic monitoring of areas of environmental interest, based on a wireless network of acoustic sensors (microphones), and the automated generation of multi-level sound maps for environmental assessment has been recently proposed. This contribution focuses on the relation between the density of the wireless nodes and node operational parameters, like the required communication rate, data compression and power autonomy, in each one of the proposed area coverage schemes/network architectures. The results provide the grounds both for the selection of the hardware architecture on network and on node level, but also for the decision on the distribution of the processing effort between the local and the central processing units.Öğe Wireless Sensor Network-based Water Quality Monitoring System(Trans Tech Publications Ltd, 2014) Tuna, Gurkan; Nefzi, Bilel; Arkoc, Orhan; Potirakis, Stelios M.Water is vital for both nature and human beings. The construction of dams and embankments, the irrigation practices, and the anthropogenic activities influence water quality. In order to control water quality, it is essential to understand the sources of pollutants. Water quality monitoring requires the collection of large numbers of samples and long delays until the results are available. Therefore, rapid monitoring of water quality is very important. In this respect, numerous systems exist for this kind of automatic monitoring. In this study, we propose a wireless sensor network (WSN)-based monitoring system controlled by a web-based online interface which allows the remote monitoring via Internet. This brings advantages over traditional monitoring systems in terms of cost effectiveness, portability and applicability. Field tests in the water reservoir of Kirklareli (Kirklareli dam), Turkey, are in progress.