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Analyzing the Water Budgets of Reservoirs by Using Autonomous Mini Boats
(Trans Tech Publications Ltd, 2014) Tuna, Gurkan; Arkoc, Orhan; Potirakis, Stelios M.; Nefzi, Bilel
The 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.
An Android Application to Secure Text Messages
(IEEE, 2017) Demirol, Doygun; Das, Resul; Tuna, Gurkan
For mobile phone users, short message service (SMS) is the most commonly used text-based communication type on mobile devices. Users can interact with other users and services via SMS. For example, users can send private messages, use information services, apply for a job advertisement, conduct bank transactions, and so on. Users should be very careful when using SMS. During the sending of SMS, the message content should be aware that it can be captured and act accordingly. Based on these findings, the elderly, called as Silent Generation which represents 70 years or older adults, are text messaging much more than they did in the past. Therefore, they need solutions which are both simple and secure enough if there is a need to send sensitive information via SMS. In this study, we propose and develop an android application to secure text messages. The application has a simple and easy-to-use graphical user interface but provides significant security.
ANN-Based Control of a Multiboat Group for the Deployment of an Underwater Sensor Network
(Hindawi Ltd, 2014) Michailidis, Emmanouel T.; Tuna, Gurkan; Gezer, Gulsum; Potirakis, Stelios M.; Gulez, Kayhan
Underwater sensor networks (USNs) can be used for several types of commercial and noncommercial applications. However, some constraints resulting from the nature of aquatic environments severely limit their use. Due to constraints such as large propagation latency, low-bandwidth capacity, and short-distance communications, a large number of USN nodes are deployed to provide reliability in most applications. In this study, an unattended deployment approach based on the use of an autonomous boat group is proposed. A map of the deployment zone and optimal locations of USN nodes are fed into the onboard computers of the boat group. After processing these data and determining paths to be followed, the boat group deploys sensor nodes at predetermined locations. During the deployment, the boat group is controlled by an artificial neural network-(ANN-) based control system for reducing path errors. A set of performance evaluations is given to prove efficiency of the proposed control system. Performance results show that the boat group can successfully follow a predefined path set and deploy USN nodes. The tradeoffs between energy consumptions, end-to-end delay, and number of hops between underwater relay nodes of energy-efficient USN are also examined. The results indicate that increasing the number of hops reduces the total energy consumption and the end-to-end delay.
ANN-Based Estimation of Groundwater Quality Using a Wireless Water Quality Network
(Hindawi Ltd, 2014) Kilicaslan, Yilmaz; Tuna, Gurkan; Gezer, Gulsum; Gulez, Kayhan; Arkoc, Orhan; Potirakis, Stelios M.
Water is essential for life. Considering its importance for humans, it must be periodically analyzed to ensure its quality. In this study, a wireless water quality network is deployed to collect water quality parameters periodically and an artificial neural network-based estimation method is proposed to estimate groundwater quality. Estimating groundwater quality enables the authorities to take immediate actions for ensuring water quality. Compared to traditional water quality analysis methods, the proposed method has the advantage of letting the authorities know the quality of their water resources beforehand. A set of simulation studies given in this paper proves the efficiency and accuracy of the proposed method.
Autonomous Intruder Detection System Using Wireless Networked Mobile Robots
(IEEE, 2012) Tuna, Gurkan; Tasdemir, Coskun; Gulez, Kayhan; Mumcu, Tarik Veli; Gungor, Vehbi Cagri
Wireless networked mobile robots pursuing a common objective are envisioned to be an efficient solution for many military, industrial, commercial, and environmental applications. This paper presents the design considerations of an autonomous intruder detection system based on wireless networked robots. Specifically, three critical aspects of these systems, such as coordination and task allocation, communication, and map-based intruder detection, have been investigated and a multi-sensor fusion mechanism has been presented. Performance results show that the fusion of redundant information from different sensors can increase the accuracy of a system and reduce overall uncertainty in intruder detection applications.
An autonomous wireless sensor network deployment system using mobile robots for human existence detection in case of disasters
(Elsevier, 2014) Tuna, Gurkan; Gungor, V. Cagri; Gulez, Kayhan
This paper presents a novel approach of using autonomous mobile robots to deploy a Wireless Sensor Network (WSN) for human existence detection in case of disasters. During WSN deployment, mobile robots perform cooperative Simultaneous Localization and Mapping (SLAM) and communicate over the WSN. The proposed system has important advantages over a human-assisted system, including autonomous deployment, aggregated intelligence, and flexibility. However, the realization of these envisaged gains depends on communication and coordination capabilities of the system. In this study, the advantages of an autonomous WSN deployment system by mobile robots, design principles and implementation related issues have been explained. In addition, simulation studies have been performed to show the effectiveness of the proposed approach considering WSN coverage, coordination strategies, and SLAM perspectives. Overall, this paper addresses the advantages of using multiple robots for WSN deployment in terms of cooperative exploration and cooperative SLAM, the benefit of simultaneously deploying wireless sensor nodes during the exploration of an unknown deployment zone and the use of WSN-based communication as an alternative communication method during exploration. (C) 2012 Elsevier B.V. All rights reserved.
Clustering-based energy-efficient routing approach for underwater wireless sensor networks
(Inderscience Enterprises Ltd, 2018) Tuna, Gurkan
In underwater wireless sensor networks (UWSNs), although energy dissipation in transmission mainly depends on employed routing algorithms and media access control (MAC) schemes, given the nature and challenges of the acoustic communication in water, all the layers of the protocol stack play an important role on achieving a high energy efficiency. Therefore, novel approaches that handle energy inefficiencies and extend the lifetime of UWSNs are required. In this paper, an event-driven energy-efficient routing approach called clustering-based energy-efficient routing (CBEER) is proposed to prolong the lifetime of UWSNs and its performance is evaluated through extensive simulations. Based on a novel clustering-based scheme, the proposed approach can find shortest routing paths to carry data packets and is able to realise uniform network energy consumption profile in the entire UWSN. The simulation-based evaluation studies reveal that CBEER performs well in terms of packet delivery ratio and overall network energy consumption.
Cognitive Radio Networks for Smart Grid Communications Potential Applications, Protocols, and Research Challenges
(Crc Press-Taylor & Francis Group, 2016) Kogias, Dimitris; Tuna, Gurkan; Gungor, Vehbi Cagri
[Abstract Not Available]
Common Network Attack Types and Defense Mechanisms
(IEEE, 2015) Das, Resul; Karabade, Abubakar; Tuna, Gurkan
For every organization having a well secured network is the primary requirement to reach their goals. A network is said to be secure if it can protect itself from sophisticated attacks. Due to the rapid increase in the number of network users, security becomes the main challenge in the area of network field. Most security related threats target the layers of the OSI reference model. Sophisticated attack types such as Distributed Denial of Service (DDoS), Man-in-the-Middle and IP spoofing attacks are used to attack these layers. In this paper, we analyze most of the attack types that cause serious problems in computer networks and defense techniques to stop or prevent these attacks.
Comparison of QoS-aware single-path vs. multi-path routing protocols for image transmission in wireless multimedia sensor networks
(Elsevier, 2014) Macit, Muhammet; Gungor, V. Cagri; Tuna, Gurkan
Wireless multimedia sensor network (WMSN) applications require strong multimedia communication competence. Therefore, in WMSN applications, it is necessary to use specific mechanisms in order to handle multimedia communication challenges and address desired energy efficiency and reliability goals. Nevertheless, the existing communication protocols are not suitable for the communication challenges and the desired goals. In this respect, specific mechanisms for prioritization, link-quality estimation and multi-path selection can be employed by quality of service (QoS)-aware routing protocols to meet the reliability and delay requirements of WMSN applications. In this study a novel approach is proposed to set different reliability values for image packets for image transmission in WMSNs. Using this prioritization, important parts of an image are assigned high priority and take priority during data transmission. In order to evaluate the proposed approach, the performance of single-path and multi-path QoS-aware routing protocols has been investigated for WMSN-based image transmission applications. Specifically, comparative performance analysis of single-path routing and multi-path routing in image transmission have been conducted in terms of peak signal-to-noise ratio (PSNR), average delay, reachability, and control overhead. As proven by the results of the performance evaluations in this study, multi-path routing is better than single-path routing in terms of reliability. On the other hand, at high traffic loads, multi-path routing may perform worse in terms of delay due to its associated overhead. (C) 2014 Elsevier B.V. All rights reserved.
Continuous Monitoring of Water Quality Using Portable and Low-Cost Approaches
(Sage Publications Inc, 2013) Tuna, Gurkan; Arkoc, Orhan; Gulez, Kayhan
Water quality refers to the physical, chemical, and biological characteristics of water, and it is a measure of the condition of water relative to any human need or purpose. A particular problem with measuring the condition of water quality at drinking water reservoirs is the requirement of collecting a large number of samples. To handle this problem, we focus on the practical use of two different portable and low-cost approaches for continuous monitoring of water quality: miniboats loaded with sondes with probes and wireless sensor network-(WSN-) based monitoring system. These approaches bring several advantages over traditional monitoring systems in terms of cost, portability, and applicability. Our simulation studies show that these systems can be used to monitor water quality at drinking water reservoirs such as dams and holding ponds. Field tests to prove the effectiveness of the proposed systems are in progress.
Cryptolog: A new approach to provide log security for digital forensics
(Istanbul Univ, Fac Engineering, 2017) Baykara, Muhammet; Das, Resul; Tuna, Gurkan
As security vulnerabilities generated by the developments in information and communication technologies as well as emerging technologies can lead to severe loss in terms of individual and institutional aspects, the importance of information security has been increasing in recent years. Nowadays, digital information is considered as an important asset which must be appropriately evaluated and protected against all forms of unauthorized access, use, disclosure, modification, destruction, or denial. Since information security is more prominent and more important now than ever before, this growing awareness of digital information security has led societies to develop innovative ways of protecting their sensitive information. On the other hand, in today's digital world, keeping sensitive information secure is not as easy as it was in the past. In this regard, it is obvious that for all types of institutions there is a need for security software which provides the necessary security measures and policies for the protection and retrieval of sensitive digital information. To ensure information security, security software must have the ability to make logging of certain events. Through log files, some analysis can be performed to find out what kind of attacks were done by which users and when. In this respect, this study proposes a novel approach of recording traffic flow on the log files stored on a server to determine the changes made by unauthorized people/users on the log records, and this way ensures the security of the log records and contributes to digital forensics processes in terms of accuracy, integrity and confidentiality of the log records.
Design considerations of UAV-aided automated meter reading
(Wydawnictwo Sigma-N O T Sp Z O O, 2012) Tuna, Gurkan
This paper introduces a new approach of using mini/micro unmanned aerial vehicles (UAVs) for automatic meter reading (AMR) in rural areas where there are subscribers dispersed over a large area. Compared to other AMR systems, the use of UAVs brings many advantages including easy integration to existing AMR systems, flexibility, and low-cost and automatic operation. In this paper, design considerations and associated challenges of this approach are presented. In addition, simulation studies are given to prove the effectiveness of the proposed approach.
Design Strategies of Unmanned Aerial Vehicle-Aided Communication for Disaster Recovery
(IEEE, 2012) Tuna, Gurkan; Mumcu, Tarik Veli; Gulez, Kayhan
This paper presents a novel approach of using unmanned aerial vehicles (UAVs) to establish a communication infrastructure in case of disasters. Due to the collapse of buildings, power systems, and antennas, the collapse of communication infrastructure is the usual effect of disasters. In this study, we propose an emergency communications system established by unmanned aerial vehicles (UAVs). The system is a post-disaster solution; hence, it can be used anywhere required. In this study, first we briefly explain the details of the system in three aspects: end-to-end communication, localization and navigation, and coordination Then, we evaluate the efficiency of the localization and navigation subsystem. Our simulation studies with Air Robot quadrotor helicopters in Unified System for Automation and Robot Simulation (USARSim) simulation environment show that UAV-aided communications system can be used in case of disasters to establish an emergency communications infrastructure in terms of localization and navigation.
Detection of Hazardous Liquids Using Microwave Data and Well-Known Classification Algorithms
(Pleiades Publishing Inc, 2020) Efeoglu, Ebru; Tuna, Gurkan
The recent increase in terrorist attacks realized using liquid explosives has made it important to develop quick and reliable methods that can distinguish between nonhazardous liquids and other liquids that can be used in these explosives. Since the stability and sensitivity properties of microwave systems are high, microwave frequency band is preferred to differentiate hazardous liquids from non-hazardous liquids. In this study, a noncontact system based on electromagnetic response measurements of liquids in microwave frequency band is proposed to develop a classification approach that can be used in liquid scanners. Naive Bayes, linear discriminant analysis, qualitative data analysis, support vector machine, sequential minimal optimization, K-nearest neighbors classification algorithms are used to classify liquids and their classification performances are analyzed. The results of the set of classification experiments prove the success of the proposed measurement method. As the results prove, K-nearest neighbors is the most appropriate classification algorithm for hazardous liquid detection. Since it can be easily implemented and its detection process is fast, a classification system based on the proposed approach can be very useful in airports and shopping malls.
Determination of salt concentration in water using decision trees and electromagnetic waves
(Iwa Publishing, 2022) Efeoglu, Ebru; Tuna, Gurkan
Salt water adversely affects human health and plant growth. In parallel with the increasing interest in non-contact determination of salt concentration in water, a novel approach is proposed in this study. In the proposed approach, S parameter measurements, which show the scattering properties of electromagnetic waves, are used. First, the relationship between salt concentration in water and permittivity values, a distinguishing feature for liquids, is shown. Then, based on the derived correlations from a set of S parameter measurements, it is shown that the salt concentration in water can be predicted. Finally, after exactly determining the relations of permittivity, salt concentration and S parameter, a system that allows non-contact determination of salt concentration is proposed. Since the proposed system makes its prediction using a classifier, decision tree algorithms are employed for this purpose. In order to evaluate the appropriateness and success of the algorithms, a set of classification experiments were held using various water samples with different levels of salt concentration. The results of the classification experiments show that the Hoeffding tree algorithm achieved the best results and is the most suitable decision tree algorithm for determining the salt concentration of liquids. For this reason, the proposed non-contact approach can be used to determine the salt concentration in water reliably and quickly if its hardware and software components can be embedded into a prototype system.
EDHRP: Energy efficient event driven hybrid routing protocol for densely deployed wireless sensor networks
(Academic Press Ltd- Elsevier Science Ltd, 2015) Faheem, Muhammad; Abbas, Muhammad Zahid; Tuna, Gurkan; Gungor, Vehbi Cagri
Efficient management of energy resources is a challenging research area in Wireless Sensor Networks (WSNs). Recent studies have revealed that clustering is an efficient topology control approach for organizing a network into a connected hierarchy which balances the traffic load of the sensor nodes and improves the overall scalability and the lifetime of WSNs. Inspired by the advantages of clustering techniques, we have three main contributions in this paper. First, we propose an energy efficient cluster formation algorithm called Active Node Cluster Formation (ANCF). The core aim to propose ANCF algorithm is to distribute heavy data traffic and high energy consumption load evenly in the network by offering unequal size of clusters in the network. The developed scheme appoints each cluster head (CH) near to the sink and sensing event while the remaining set of the cluster heads (CHs) are appointed in the middle of each cluster to achieve the highest level of energy efficiency in dense deployment. Second, we propose a lightweight sensing mechanism called Active Node Sensing Algorithm (ANSA). The key aim to propose the ANSA algorithm is to avoid high sensing overlapping data redundancy by appointing a set of active nodes in each cluster with satisfy coverage near to the event. Third, we propose an Active Node Routing Algorithm (ANRA) to address complex inter and intra cluster routing issues in highly dense deployment based on the node dominating values. Extensive experimental studies conducted through network simulator NCTUNs 6.0 reveal that our proposed scheme outperforms existing routing techniques in terms of energy efficiency, end-to-end delay and data redundancy, congestion management and setup robustness. (C) 2015 Elsevier Ltd. All rights reserved.
The effects of exploration strategies and communication models on the performance of cooperative exploration
(Elsevier, 2013) Tuna, Gurkan; Gulez, Kayhan; Gungor, V. Cagri
Exploration with mobile robots is utilized in a wide range of applications including search and rescue missions, planetary exploration, homeland security; surveillance, and reconnaissance. Cooperative exploration offers the potential of exploring an unknown zone more quickly and robustly than single-robot case. However, coordinating multiple robots is a challenging task due to heterogeneous processing and communication requirements, and the complexities of exploration algorithms. This paper presents a comparison of different cooperative exploration strategies, such as frontier-based exploration, market-driven exploration, and role-based exploration, based on their exploration performances and processing time requirements. To show the effect of CPU power on the processing time of the exploration algorithms, two notebooks and a netbook with different specifications have been extensively used. Comparative simulation results of our own application developed in Java show that the processing time requirements are consistent with the computational complexities of the exploration strategies. The results we obtained are consistent with the CPU power tests of independent organizations, and show that higher processing power reduces processing time accordingly. (C) 2012 Elsevier B.V. All rights reserved.
EXPLORATION AND MAPPING OF ANCIENT UNDERGROUND TUNNELS WITH A HETEROGENEOUS ROBOT TEAM
(Stef92 Technology Ltd, 2016) Savran, Dogan; Tuna, Gurkan
Although archaeologists have a great desire to uncover ancient underground tunnels, it is a really hard work since most of the ancient tunnels are very small, measuring only around 60 in width, typically just enough for a person to crawl through. In addition, although most ancient underground tunnels include small rooms and storage chambers in some places, since the tunnels are generally very long, exploring and mapping those tunnels is not practical at all by using such an approach. In this paper, we present a novel approach to explore and map ancient underground tunnels. The approach we present is based on a combination of autonomous mobile robots, namely a water-proof autonomous mobile robot and an unmanned aerial vehicle. In our approach, while the mobile robot is responsible for exploring and mapping of underground tunnels, the unmanned aerial vehicle is used to map and localize the tunnels on a global map. With a set of calculations realized with handheld highly-accurate GPS devices, possible mapping errors are minimized. A case study is presented to explain the proposed approach.
Exploration Strategy Related Design Considerations of WSN-Aided Mobile Robot Exploration Teams
(Springer-Verlag Berlin, 2012) Tuna, Gurkan; Gulez, Kayhan; Gungor, Vehbi Cagri; Mumcu, Tarik Veli
This paper presents a novel approach to mobile robot exploration. In this approach, mobile robots send their local maps to the central controller and coordinate with each other using a wireless sensor network (WSN). Different from existing rendezvous point-based exploration strategies, the use of a WSN as the communication media allows quick and cost-effective exploration and mapping of an unknown environment. Overall, this paper introduces WSN-aided mobile robot exploration strategy and shows comparative performance evaluations using the Player/Stage simulation platform. Here, our main goal is to present potential advantages of WSN-aided mobile robot exploration for Simultaneous Localization and Mapping (SLAM).

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