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Conference Object Citation - WoS: 4Citation - Scopus: 6A Reinforcement Learning Algorithm for Data Collection in Uav-Aided Iot Networks With Uncertain Time Windows(Ieee, 2021) Cicek, Cihan TugrulUnmanned aerial vehicles (UAVs) have been considered as an efficient solution to collect data from ground sensor nodes in Internet-of-Things (IoT) networks due to their several advantages such as flexibility, quick deployment and maneuverability. Studies on this subject have been mainly focused on problems where limited UAV battery is introduced as a tight constraint that shortens the mission time in the models, which significantly undervalues the UAV potential. Moreover, the sensors in the network are typically assumed to have deterministic working times during which the data is uploaded. In this study, we revisit the UAV trajectory planning problem with a different approach and revise the battery constraint by allowing UAVs to swap their batteries at fixed stations and continue their data collection task, hence, the planning horizon can be extended. In particular, we develop a discrete time Markov process (DTMP) in which the UAV trajectory and battery swapping times are jointly determined to minimize the total data loss in the network, where the sensors have uncertain time windows for uploading. Due to the so-called curse-of-dimensionality, we propose a reinforcement learning (RL) algorithm in which the UAV is trained as an agent to explore the network. The computational study shows that our proposed algorithm outperforms two benchmark approaches and achieves significant reduction in data loss.Conference Object Citation - WoS: 4A Layered Security Architecture for Corporate 802.11 Wireless Networks(Ieee, 2004) Erten, YM; Tomur, EIn this study we have investigated the security aspects of wireless local area networks and discussed the weaknesses associated with various conventional 802.11 security protocols such as WEP and 802.1x. We propose an architecture to control access to corporate 802.11 wireless networks, based on the privileges and location of users, using the tested wired network components such as VPNs and Firewalls. The presented architecture reduces the security risks in enterprise level deployment of wireless LANs.Conference Object Citation - WoS: 16Citation - Scopus: 30A Search-Based Approach for Cost-Effective Software Test Automation Decision Support and an Industrial Case Study(Ieee, 2014) Amannejad, Yasaman; Garousi, Vahid; Irving, Rob; Sahaf, ZahraTest automation is a widely-used approach to reduce the cost of manual software testing. However, if it is not planned or conducted properly, automated testing would not necessarily be more cost effective than manual testing. Deciding what parts of a given System Under Test (SUT) should be tested in an automated fashion and what parts should remain manual is a frequently-asked and challenging question for practitioner testers. In this study, we propose a search-based approach for deciding what parts of a given SUT should be tested automatically to gain the highest Return On Investment (ROI). This work is the first systematic approach for this problem, and significance of our approach is that it considers automation in the entire testing process (i.e., from test-case design, to test scripting, to test execution, and test result evaluation). The proposed approach has been applied in an industrial setting in the context of a software product used in the oil and gas industry in Canada. Among the results of the case study is that, when planned and conducted properly using our decision-support approach, test automation provides the highest ROI. In this study, we show that if automation decision is taken effectively, test-case design, test execution, and test evaluation can result in about 307%, 675%, and 41% ROI in 10 rounds of using automated test suites.Conference Object Design and Implementation of an Expressive Talking Mobile Robot: Toztorus(Ieee, 2018) Tozan, Ozalp; Tora, Hakan; Uslu, Baran; Unal, Bulcnt; Ceylan, EceThis paper is about a brand new robot and all its development stages from the design to the show time. As an undergraduate research project (the LAP program at Atilim University), the robot TozTorUs is the outcome of the dense efforts of a team. With the sensors equipped, it navigates autonomously in the environment in which it is located by avoiding the obstacles. It can understand your questions and answer them using Google's speech technologies. Although it is not a humanoid robot, with eyes and mouth simulator LED displays, it is as friendly as a human. We can also control TozTorUs using a mobile phone. Apart from these, it is able to adjust its height with respect to the visitor's, thus allowing it to make an eye contact with the person. Although TozTorUs is designed for welcoming, it may also be employed for consulting, security and elderly assistance.Conference Object Citation - WoS: 1Characterization of Satellite Transponder Impairments Based on Simulations with Test Data(Ieee, 2015) Ulubey, Orhan; Gulgonul, Senol; Kara, AliA satellite transponder simulator based on actual test data of TURKSAT 3A satellite has been developed to analyze degradation in multicarrier scenarios. Communication impairment sources through a transponder are explained in conjunction with a methodology defined to characterize total degradation resulting from them. Several transponder utilization scenarios are studied with respect to total degradation and optimum operation conditions are demonstrated.Conference Object Citation - WoS: 7Citation - Scopus: 8Formation Control of a Multi-Agent System Using Decentralized Nonlinear Servomechanism(Ieee, 2003) Gazi, VIn this article we consider the formation control problem of a system of M agents with general nonlinear dynamics. We show that the problem of the agents moving in a formation along constant or periodic trajectories can be formulated as a nonlinear output regulation (servomechanism) problem and solved using known techniques. Then, we consider the example of formation control of agents with point mass dynamics and apply the procedure. Few illustrative numerical simulation examples are also provided.Conference Object Citation - WoS: 13Citation - Scopus: 34Swarm Aggregations Using Artificial Potentials and Sliding Mode Control(Ieee, 2003) Gazi, VIn this article we build on our earlier results in [1, 2] on swarm stability. In [1, 2] we had considered aggregating swarm model in n-dimensional space based on artificial potential functions for inter-individual interactions and motion along the negative gradient of the combined potential. Here we consider a general model for vehicle dynamics of each agent (swarm member) and use sliding mode control theory to force their motion to obey the dynamics of the swarm considered in [1, 2]. In this context, the results in [1, 2] serve as a "proof of concept" for swarm aggregation, whereas the present results serve as possible implementation method for engineering swarms with given vehicle dynamics. Moreover, the presented control scheme is robust with respect to disturbances and system uncertainties.Conference Object Citation - WoS: 2Fem-Based Design Modifications and Efficiency Improvements of a Brushed Permanent Magnet Dc Motor(Ieee, 2017) Tarvirdilu-Asl, Rasul; Zeinali, Reza; Ertan, H. BulentThis paper describes design modifications of a brushed permanent magnet DC motor. Test motor is modeled using a Finite Element Method (FEM) based software. Model accuracy is investigated by comparing measurement and simulation results. Reducing material consumption in motor fabrication while the motor develops the desired torque at a higher efficiency is aimed in this paper. Modifications are done in three stages and simulations results are also presented. These results are also compared to simulation results of the test machine.Conference Object Citation - WoS: 2A Proposal on Requirements for Cosmic Fsm Automation From Source Code(Ieee, 2016) Tarhan, Ayca; Ozkan, Baris; Icoz, Gonca CananAutomation of functional size measurement (FSM) process has increasingly gained importance since manual measurement is time-consuming, costly, and sometimes error-prone. There exist studies that automate measurement from different software artifacts such as requirements specifications, design models, and software code. In this study we review and compare four studies that we have carried out in recent years to automate COSMIC FSM from software code. Based on the comparison and the lessons learned, we derive an operational scenario for automated FSM from software code and propose a set of requirements that need to be considered in automation. We think the proposal will be helpful not only for our future studies and also for future work of interested researchers.Conference Object Distance Laboratory Applications Errl(Ieee, 2008) Aydin, C. C.; Turkmen, G.; Ozyurt, E.; Aydin, E. U.; Cagiltay, N. E.; Ozbek, M. E.; Kara, A.In the last decade, the effect of internet usage in education is gradually increased. When we look from academic perspective, the new technologies provided alternatives for students learning. As distance education becomes important everyday, the indispensable elements of teaching and education, laboratories must be reachable via remote connection. Consequently, the education that is going to be given to the students will be more flexible with respect to place and time constraints and students can reach laboratory facilities at any time and anywhere not only in lectures and practical hours. In this study, European Remote Radio Laboratory (ERRL) which is a distance remote Radio Frequency (RF) laboratory designed for electrical-electronics students, is described generally. The software architecture, infrastructure and experiment that can be done with a remote connection have been described.
