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Article Customizing Ssl Certificate Extensions To Reduce False-Positive Certificate Error/Warning Messages(International Journal of Information Security Science, 2016) Tarazan, Şafak; Bostan, AtilaIn today’s Internet world, X.509 certificates are commonly used in SSL protocol to provide security for web-based services by server/client authentication and secure communication. Although SSL protocol presents a technical basis, this web security largely depends on user awareness of security measures as well. There are significant number of scientific studies in the literature reporting that the count of invalid or self-signed certificate usage in today’s Internet can not be overlooked. At the same time, quite a number of studies place emphasis on the acquired indifference towards certificate warning messages which are popped up by web browsers when visiting web pages with invalid or self-signed certificates. In this study, with the importance of user’s daily practices in developing habits in mind, we studied a modification of X.509 certificates in order to reduce the number of false-positive certificate-warning pop ups in order to reduce gaining faulty usage habit of invalid certificates.Article How To Teach Usage of Equipments in a Remote Laboratory(IEEE, 2007) Alparslan, Nimet Ceren; Çağıltay, Nergiz; Özen, Mustafa; Aydın, ElifEuropean Remote Radio Laboratory (ERRL) is an e learning project for students, teachers and technicians of the universities who will use the very important devices of this laboratory remotely. These devices are very expensive to buy and can be broken easily while they have been using by the people who does not really know how to use them professionally. As a solution we have developed an e-learning system which aims to support the ERRL learners while studying on how to use equipments in the system. The system is developed according to the electronic performance support systems (EPSS) approach. An EPSS is a computer-based, well structured system which improves the performance of individuals. It is an electronic infrastructure that contains, stores and distributes personal (individual) or corporate knowledge to enable people to reach necessary levels of performance in the fastest possible time and with minimum teaching support of other people. This paper discusses how the content for such a system is developed and how this content is interactively used in the EPSS platform. The technical details of the developed EPSS are also discussed in this study. We believe that this paper will help instructional system designers for designing different alternatives to improve learners’ performance.Article Flotation of Refractory Marmatite Ore by Using Ammoniacal Copper (ii) Solution as Activator(The International Journal of Mineral Resources Engineering, 2008) Rao, Feng; Song, Shaoxian; Tong, Xiong; Xıe, Xian; Lopez-valdıvıeso, AlejandroThe flotation of a refactory marmatite ore in China has been studied by using ammoniacal copper (II) solution as the activator in this work, in order to improve the Zn recovery of the marmetite flotation. The experimental results have shown that the ACS could increase the Zn recovery of 9%, compared withcopper sulphate (a commonly used activator for sphalerite and marmatite). The marmatite flotation with the ACS as activator consume much less lime because it was realized at pH 9, while that with copper sulphate as the activator is carried out around pH 12. The less lime consumption not only leads to savings on operation costs, but also reduces the corrosions of flotation celss and stirring tanks, etc. The mechanism by which the ACS acts as activator in marmatite flotation has been found to be attributed to the chemical adsorption of copper (II)-ammonia complexes (CuNH32 and Cu(NH3)22) on marmatite surfaces, leaving to active sites on the surfaces for the adsorption of xanthate ions.Article Using Bluetooth Low Energy Beacons for Indoor Localization(International Journal of Intelligent Systems and Applications in Engineering, 2017) Şengül, Gökhan; Karakaya, MuratBluetooth Low Energy (BLE) Beacons gain high popularity due to their low consumption of energy and, thereby, long lifetime. Using the BLE protocol, these devices emit advertisement packets at fixed intervals for a short duration. Indoor localization solutions aim to provide an accurate, low cost estimate of sub-room indoor positioning. There are various techniques proposed for this purpose. BLE Beacons are good hardware candidates to assist the creation of such indoor localization solutions. Given the exact position of BLE Beacons, one can attempt to estimate a receiver position according to the received signal power. In this work, we investigated the success of such an indoor localization approach employing multiple BLE Beacons and two different estimation techniques. The results of the experiments indicate that employing multiple BLE Beacons increases the success of prediction techniques considerably.Article Symplectic and multi-symplectic methods for coupled nonlinear Schrödinger equations with periodic solutions(Computer Physics Communications, 2007) Aydın, Ayhan; Karasözen, BülentWe consider for the integration of coupled nonlinear Schrödinger equations with periodic plane wave solutions a splitting method from the class of symplectic integrators and the multi-symplectic six-point scheme which is equivalent to the Preissman scheme. The numerical experiments show that both methods preserve very well the mass, energy and momentum in long-time evolution. The local errors in the energy are computed according to the discretizations in time and space for both methods. Due to its local nature, the multi-symplectic six-point scheme preserves the local invariants more accurately than the symplectic splitting method, but the global errors for conservation laws are almost the same.Article A Smart Classroom Application: Monitoring and Reporting Attendance Automatically Using Smart Devices(International Journal of Scientific Research in Information Systems and Engineering, 2017) Şengül, Gökhan; Karakaya, Murat; Bostan, AtilaFor recording attendance in a classroom, generally instructors collect signatures of the attendees. Then, at the end of the semester, those signatures need to be counted and reported. This process causes waste of time and effort for both instructors and attendees. Besides this process is very error prone. Moreover, in crowded classes, there could be some misuses of this process. In this study, a smart classroom application is proposed and developed in order to monitor the attendance of the students in a classroom environment. In the design, a low-energy Bluetooth device is located at each classroom. Identification number (ID) of the low-energy Bluetooth device and the name/number of the classroom that the device is located are matched and stored in a central database. In addition to this information, the name of the courses given in that classroom and their time tables are also stored in the central database. Thus, in the database, the weekly course schedule of the classrooms is available. In addition to this central database infrastructure, a mobile application is developed that can run on both in mobile phones and smart watches. The users first install the application on their own smart devices. Whenever an attendee enters to a classroom, the smart device and its application interacts with the low-energy Bluetooth device. The student’s identification number (Student ID: SID), the identification number (ID) of the low-energy Bluetooth device located at the class, the day and time of the interaction are sent to the central database by the smart device. Using this information, the name of the attendee and the courses that he/she attended are matched using the SID of the attendee, the ID of the low-energy Bluetooth device, the day and time of the interaction. Those matching information are also stored in the central database. The records in the central database are used to create any automatic reports, i.e. the attendance status, the time and duration of the attendance, and the classroom (course) of the record. The advantage of the proposed system is that it is a fully automatic system that records the presence of the students, generates automatic attendance reports, does not require any extra device except installing a mobile application onto smart phones or smart watches of the student, and can be deployed with a low budget. The proposed system is tested in real classroom environment and it is proven to be operational.Article Design and Development of a Remote and Virtual Environment for Experimental Training in Electrical and Electronics Engineering(2010 9th International Conference on Information Technology Based Higher Education and Training (ITHET), 2010) Kara, Ali; Aydın, Elif; Özbek, Mehme Efe; Çağıltay, NergizEuropean Remote Radio Laboratory (ERRL) has been developed by the support of European Commission. It intends to provide remote access to high cost devices remotely, and perform experiments in radio frequency (RF), communications and microwave domains of Electrical and Electronics Engineering. The system has been operational for two years, and been integrated into curriculum of some courses. In this work, the hardware and software structures of the system are presented. Then, experimental content and the motivations in the design of the system are discussed.Article Teaching Usage of Equipments in a Remote Laboratory(2008) Alparslan, Nimet Ceren; Çağıltay, Nergiz; Özen, Mustafa; Aydın, ElifRemote laboratories are technologies that aim to increase the effectiveness of educational programs. European Remote Radio Laboratory (ERRL) is an e-learning project for students, teachers and technicians who will use very important devices of a radio frequency laboratory remotely. As a solution we have developed an e-learning system which aims to support the ERRL learners while studying on how to use equipments in the system. The system is developed according to the electronic performance support system (EPSS) approach. An EPSS is a computer-based, well-structured system which improves the performance of individuals. It is an electronic infrastructure that contains, stores and distributes personal (individual) or corporate knowledge to enable people to reach necessary levels of performance in the fastest possible time and with minimum teaching support of other people. This paper discusses how the content for such a system is developed and how this content is interactively used in the EPSS platform. The technical details of the developed EPSS are also discussed in this study. We believe that this paper will help instructional system designers for designing different alternatives to improve learners’ performance.Article A Fixed Point Theorem for Set-Valued Quasi-Contractions in B-Metric Space(2014) Karapınar, Erdal; Aydı, Hassen; Bota, Monica-felicia; Mıtrovıć, SlobodankaIn this article, we give a fixed point theorem for set-valued quasi-contraction maps in b-metric spaces. This theorem extends, unifies and generalizes several well known comparable results in the existing literature.Article Maintenance, Sustainability and Extendibility in Virtual and Remote Laboratories(Social and Behavioral Sciences, 2011) Kara, Ali; Özbek, Mehmet Efe; Çağıltay, Nergiz; Aydın, ElifThis study presents discussions on sustainability of Virtual and Remote Laboratories (VRL), and provides challenges toward maintenance of VRLs. Technical and pedagogical issues in extension and sustenance of VRLs are discussed with the experiences of the authors gained in the development of a VRL system, European Remote Radio Laboratory (ERRL) platform. Moreover, the study presents actions to be taken in sustenance plan and expendability of VRL system with the advances in Information and Communication Technologies (ICT) and educational technologies along with the needs of educators and learners in formal education.
