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Article Determination of Measurement Noise, Conductivity Errors and Electrode Mislocalization Effects To Somatosensory Dipole Localization(Biomedical Research, 2012) Şengül, Gökhan; Baysal, UğurCalculating the spatial locations, directions and magnitudes of electrically active sources of human brain by using the measured scalp potentials is known as source localization. An accu rate source localization method requires not only EEG data but also the 3-D positions and number of measurement electrodes, the numerical head model of the patient/subject and the conductivities of the layers used in the head model. In this study we computationally deter mined the effect of noise, conductivity errors and electrode mislocalizations for electrical sources located in somatosensory cortex. We first randomly selected 1000 electric sources in somatosensory cortex, and for these sources we simulated the surface potentials by using av erage conductivities given in the literature and 3-D positions of the electrodes. We then added random noise to measurements and by using noisy data; we tried to calculate the positions of the dipoles by using different electrode positions or different conductivity values. The esti mated electrical sources and original ones are compared and by this way the effect of meas urement noise, electrode mislocalizations and conductivity errors to somatosensory dipole lo calization is investigated. We conclude that for an accurate somatosensory source localization method, we need noiseless measurements, accurate conductivity values of scalp and skull lay ers and the accurate knowledge of 3-D positions of measurement sensors.Article Classification of Parasite Egg Cells Using Gray Level Cooccurence Matrix and Knn.(Biomedical Research, 2016) Şengül, GökhanParasite eggs are around 20 to 80 μm dimensions, and they can be seen under microscopes only and their detection requires visual analyses of microscopic images, which requires human expertise and long analysis time. Besides visual analysis is very error prone to human procedures. In order to automatize this process, a number of studies are proposed in the literature. But there is still a gap between the preferred performance and the reported ones and it is necessary to increase the performance of the automatic parasite egg classification approaches. In this study a learning based statistical pattern recognition approach for parasite egg classification is proposed that will both decrease the time required for the manual classification by an expert and increase the performance of the previously suggested automated parasite egg classification approaches. The proposed method uses Gray-Level Co-occurrence Matrix as the feature extractor, which is a texture based statistical method that can differentiate the parasite egg cells based on their textures, and the k-Nearest Neighbourhood (kNN) classifier for the classification. The proposed method is tested on 14 parasite egg types commonly seen in humans. The results show that proposed method can classify the parasite egg cells with a performance rate of 99%.Article Unidirectional Data Transfer: a Secure System To Push the Data From a High Security Network To a Lower One Over an Actual Air-Gap(International Journal of Scientific Research in Information Systems and Engineering, 2017) Şengül, Gökhan; Bostan, Atila; Karakaya, MuratThe term “air-gap” is typically used to refer physical and logical separation of two computer networks. This type of a separation is generally preferred when the security levels of the networks are not identical. Although the security requirements entail parting the data networks, there is a growing need for fast and automatic transfer of data especially from high-security networks to low-security ones. To protect security sensitive system from the risks originating from low-security network, unidirectional connections that permit the data transfer only from high to low-security network, namely information-diodes, are in use. Nonetheless, each diode solution has its drawbacks either in performance or security viewpoints. In this study, we present a unidirectional data transfer system in which the primary focus is data and signal security in technical design and with a plausible and adaptable data transfer performance. Such that the networks do not touch each other either in physically or logically and the transfer is guaranteed to be unidirectional. Apart from avoiding the malicious transmissions from low to high-security network, we claim that the proposed data diode design is safe from emanation leakage with respect to the contemporary sniffing and spoofing techniques.Article Bilimsel İletişimde Yeşil ve Altın Yollarda Yakınsama ve Türkiye’deki Yansımaları(Bilgi Dünyası, 2011) Ertürk, Korhan Levent; Şengül, GökhanSon yıllarda özellikle sosyal ağlarda bilgi dolaşımının artması, gelişmiş mobil iletişim cihazlarının yoğun kullanımı kısıtsız ve farklı ortamlarda bilgi erişim ve paylaşımını gerektirmektedir. Bu bağlamda bilimsel bulguların yer aldığı makalelerin geniş kitlelere ve diğer bilim insanlarının erişimine açılması; hem bilimsel eserin doğruluk ve güvenirliğini artırmaya yardımcı olmakta, hem de bilimsel verinin paylaşılmasını ve dolayısı ile de bilimsel gelişimi olumlu yönde etkilemektedir. Yaklaşık on yıldır bu amaca açık erişim insiyatifi katkı sağlamaktadır. Bu amaçla kendi kendine arşivleme (yeşil yol) ve açık erişim dergisi (altın yol) bilimsel çalışmaların bilim topluluğuna sunulmasında yeni yöntemler olarak takdim edilmiştir Bu çalışmada; uluslararası alanda yeşil ve altın yollar üzerinde ortaya konan kurallar irdelenmiş, yazar ve yayıncılarının oluşan iklime uyumluluğu sorgulanmış ve Türkiye adresli kurumsal arşiv ve dergilerin ortaya çıkan durum karşısında konumları üzerine bir değerlendirme yapılmıştır. Çalışma esnasında Ulrich Süreli Yayın Rehberi, Thomson Reuters (ISI) Bilimsel Web (Web of Science - WoS) ve Elsevier Scopus uluslararası ticari atıf veri tabanları, RoMEO, Juliet, ve ROARMAP telif politikası rehberleri, OpenDOAR, ROAR kurumsal arşiv rehberleri ve DOAJ açık erişim dergisi rehberi ile ULAKBİM ulusal veri tabanları incelenmiştir.Article Biometric Verification on E-Id Secure Access Devices: a Case Study on Turkish National E-Id Card Secure Access Device Specifications(International Journal of Information Security Science, 2017) Bostan, Atila; Şengül, Gökhan; Karakaya, MuratBiometric verification on e-ID cards requires clear procedures and standards be defined, especially when the access devices are anticipated to be produced commercial companies. Turkish national e-ID card project has reached the dissemination step. Now the commercial companies are expected to produce and market e-ID card access devices which will conduct secure electronic identity verification functions. However, published standards specifying e-ID card-access-device requirements are ambiguous on biometric verification procedures. In this study, we intended to attract scientific interest to the problems identified in the current design of biometric verification on Turkish national e-ID cards and proposed several verification alternatives which enables the production of e-ID card access devices in a commercial-competition environment.Article Türkiye’de Engelli Farkındalığı ve Engelli Bireylerin Adalete Web Erişilebilirlikleri Üzerine Bir Değerlendirme(Bilgi Dünyası, 2014) Ertürk, Korhan Levent; Şimşek, A. Aslı; Songür, Damla Gülseren; Şengül, GökhanFiziksel veya zihinsel nedenlerle bazı hareketleri, duyuları veya işlevleri kısıtlı olan bireyler toplumun bir grubunu oluşturmaktadır. türkiye’de bu bireyler ve/veya çevreleri toplumda doğrudan ya da dolaylı olarak çeşitli sorunlarla karşı karşıya kalmaktadırlar. Günümüzde eğitim, sağlık, adalet, sosyal güvenlik gibi alanlarda bu durum sıklıkla görülebilmektedir. Söz konusu bireyler sorunlarıyla ilgilenilmesini ve çözüme kavuşturulmasını istemektedirler. Bir ülkenin gelişmişlik düzeyi anılan sorunların çözümüne yönelik çalışmalar ile doğrudan ilişkilidir. Çalışmamız, bazı hareketleri, duyuları veya işlevleri kısıtlı olan bireylerin ortak bir terimle ifade edilmesi, engelli birey farkındalığının ortaya konulması ve bu bağlamda ilgili bazı web sitelerinin bu bireyler açısından yeterliliğinin sorgulanmasına yöneliktir. Web sitelerinin olabildiğince erişilebilir yapılması engelli kullanıcılara diğer bireyler ile eşit hakların sağlanmasına katkı sağlayabilecek, bilgi ve iletişim kaynaklarını çeşitlendirebilecektir.Article Determination and Identification of Dangerously Lane Changing Vehicles in Traffic by Image Processing Techniques(International Journal of Scientific Research in Information Systems and Engineering, 2017) Şengül, Gökhan; Karakaya, Murat; Bostan, AtilaDue to increase of vehicle usage all around the world, the importance of safety driving in traffic is increasing. All of the countries around the world are taking actions to increase the safety driving habitats and decrease the number of traffic accidents. One of the applied precautions is to put necessary automatic auditing mechanisms into service for controlling the drivers as they drive since reckless drivers may not obey many traffic rules. In this study, image and video processing based methods are applied to identify the dangerously lane changing vehicles/drivers in the traffic. The proposed method focuses on to detect three different violations in traffic: the vehicles frequently changing traffic lanes, the vehicles changing lanes when it is forbidden, and the vehicles overtaking the other vehicles using the right lanes instead of left one. The proposed method is based on the image and video processing techniques. It first detects the vehicles in video sequences, then tracks the vehicles in the following frames and determines the lane changes of the vehicles. In the vehicle detection phase an image subtraction method is used. In the vehicle tracking phase, Kalman filtering tracking algorithm is used. After determining the lane changes of the vehicles/drivers, a rule based decision system is used to find out the vehicles/drivers improperly changing lanes and those vehicles are marked on the video. The proposed method is tested on the videos captured from real traffic environments and promising results are obtained.Article A Comprehensive Assessment Plan for Accreditation in Engineering Education: A Case Study in Turkey(International Journal of Engineering Education, 2015) Turhan, Çiğdem; Şengül, Gökhan; Koyuncu, MuratThis paper describes the procedure followed by Computer Engineering and Software Engineering programs at Atilim University, Ankara, Turkey, which led to the granting of five years of accreditation by MUDEK, the local accreditation body authorized by The European Network for Accreditation of Engineering Education (ENAEE) to award the EUR ACE label, and a full member signatory ofWashington Accord of International Engineering Alliance (IEA). It explains the organizational structure established for preparation, determination and measurement of the educational objectives, program outcomes, course outcomes, and the continuous improvement cycle carried out during the preparation period. The aim of the paper is to share methods and experiences which may be beneficial for the other programs that are intended for accreditation.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 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.
