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Öğe Analysing the success of level determination exam according to the school type and lesson type that is represented by questions in the exam(Elsevier Science Bv, 2013) Cavusoglu, Abdullah; Sen, Baha; Ucar, Emine; Ucar, MuratThe purpose of this study is to determine if there is any relation between level determination exam (LDE) point and the type of school and the points that student got from those lessons which are represented by questions in the exam. Randomly selected data belongs to 8th degree primary school students among whole Turkey are used as the sample data. To investigate the significance level of relationship between two variables independent of each other, first of all the correlation values between two variables has been examined and then some statistical tests has been applied. As a result, it has been observed that there is a strong, meaningful and positive relation between the achievement of students on the lessons which are represented by questions in the exam and the LDE points. Furthermore, it has been observed that the type of school that students attend is also effective to the success and it has been seen that the students who attend private schools are more successful than the students in public schools. (C) 2013 The Authors. Published by Elsevier Ltd.Öğe Analysis of Demographic Characteristics Creating Coronary Artery Disease Susceptibility using Random Forests Classifier(Elsevier Science Bv, 2015) Akyol, Kemal; Calik, Elif; Bayir, Safak; Sen, Baha; Cavusoglu, AbdullahCardiovascular system diseases are an important health problem. These diseases are very common also responsible for many deaths. With this study, it is aimed to analyze factors that cause Coronary Artery Disease using Random Forests Classifier. According to the analysis, we observed correct classification ratio and performance measure that creates susceptibility to Coronary Artery Disease for each factor. The performance measure results clearly show the impact of demographic characteristics on CAD. Additionally, this study shows that random forests algorithm can be used to the processing and classification of medical data such as CAD. (C) 2015 The Authors. Published by Elsevier B.V.Öğe A Comparative Study on Classification of Sleep Stage Based on EEG Signals Using Feature Selection and Classification Algorithms(Springer, 2014) Sen, Baha; Peker, Musa; Cavusoglu, Abdullah; Celebi, Fatih V.Sleep scoring is one of the most important diagnostic methods in psychiatry and neurology. Sleep staging is a time consuming and difficult task undertaken by sleep experts. This study aims to identify a method which would classify sleep stages automatically and with a high degree of accuracy and, in this manner, will assist sleep experts. This study consists of three stages: feature extraction, feature selection from EEG signals, and classification of these signals. In the feature extraction stage, it is used 20 attribute algorithms in four categories. 41 feature parameters were obtained from these algorithms. Feature selection is important in the elimination of irrelevant and redundant features and in this manner prediction accuracy is improved and computational overhead in classification is reduced. Effective feature selection algorithms such as minimum redundancy maximum relevance (mRMR); fast correlation based feature selection (FCBF); ReliefF; t-test; and Fisher score algorithms are preferred at the feature selection stage in selecting a set of features which best represent EEG signals. The features obtained are used as input parameters for the classification algorithms. At the classification stage, five different classification algorithms (random forest (RF); feed-forward neural network (FFNN); decision tree (DT); support vector machine (SVM); and radial basis function neural network (RBF)) classify the problem. The results, obtained from different classification algorithms, are provided so that a comparison can be made between computation times and accuracy rates. Finally, it is obtained 97.03 % classification accuracy using the proposed method. The results show that the proposed method indicate the ability to design a new intelligent assistance sleep scoring system.Öğe CUDA Based Speed Optimization of the PCA Algorithm(Assoc Information Communication Technology Education & Science, 2016) Gorgunoglu, Salih; Oz, Kadriye; Cavusoglu, AbdullahPrincipal Component Analysis (PCA) is an algorithm involving heavy mathematical operations with matrices. The data extracted from the face images are usually very large and to process this data is time consuming. To reduce the execution time of these operations, parallel programming techniques are used. CUDA is a multipurpose parallel programming architecture supported by graphics cards. In this study we have implemented the PCA algorithm using both the classical programming approach and CUDA based implementation using different configurations. The algorithm is subdivided into its constituent calculation steps and evaluated for the positive effects of parallelization on each step. Therefore, the parts of the algorithm that cannot be improved by parallelization are identified. On the other hand, it is also shown that, with CUDA based approach dramatic improvements in the overall performance of the algorithm arepossible.Öğe Detailing the co-authorship networks in degree coupling, edge weight and academic age perspective(Pergamon-Elsevier Science Ltd, 2016) Turker, Ilker; Cavusoglu, AbdullahScientific collaboration networks are good resources for understanding self-organizing systems, reflecting the main generic properties like clustering, small-world and scale-free degree distribution. Beyond discovering the evolution of main parameters, we aimed to uncover the microscopic wiring properties in this study. We focused on the degree circumstances of pairing nodes together with degree differences, academic age differences and link weights. Analyzes are visualized by single distribution plots of the network parameters together with the 2D coupling characteristics of these parameters with a logarithmic colorbar as a third dimension, drawing visual perspective presenting who prefers connecting to whom during the network evolution. We showed that majority of the edges in the co-authorship network connects the nodes of comparable degrees and academic ages, featuring that strong collaboration activities occur between comparable academic careers. We also stated out that beyond the node degree distributions, power-law regimes are also observed in link weight and degree difference distributions. (C) 2016 Elsevier Ltd. All rights reserved.Öğe Detection of Eye Motion Direction in Real Time Video Image(Ieee, 2014) Atasoy, Nesrin Aydin; Cavusoglu, AbdullahIn this study, eye motion that captured by webcam is classified in real time. Eyes are detected with using Viola-Jones face detection algorithm. Iris and its center are detected with using Circle Hough Transform on single eye. Eye corners and region are determined OpenCV functions. And finally; The eye motion has been categorized in a way that it looks at down, up, left and right sides according to its distance to corner points of iris center. System is examined according to user's distance to camera and light.Öğe Developing a parameterized simulation platform with intelligent synthetic agents for training driver candidates(Elsevier Science Bv, 2011) Cavusoglu, Abdullah; Kurnaz, IsmailThis study presents a driver Traffic Training Simulator (TTS) that utilizes intelligent synthetic actors. The movements of intelligent actors are realized using a network flow graph consisting of segment nodes. The intelligent actors in traffic are capable of such objectives as vehicles and lane following. In addition, they are capable of moving according to the traffic signs and lights. The duration of traffic lights can parametrically be determined by the simulator interface. Moreover, parametric values such as weather conditions, seasons, and sunlight can be fed to the simulator as inputs. Similarly, the type of the driver's vehicle and other intelligent vehicles and their numbers can also be parametrically determined. The driver is able to drive in the heavy and light traffic conditions. Currently we are focusing on incorporating the hardware components into the system. Following the tests for the candidates with the system is expected to take place in driver training schools. (C) 2010 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of the Guest Editor.Öğe The development of a hardware- and software-based simulation platform for the training of driver candidates(Tubitak Scientific & Technological Research Council Turkey, 2013) Cavusoglu, Abdullah; Kurnaz, IsmailIn this study, a traffic simulation system (TSS) to provide novice driver candidates with opportunities for training and testing has been developed. Autonomous vehicles that follow the flow of traffic in a microsimulation environment were prepared using a hierarchical concurrent state machine. Autonomous vehicles are skilled and have behavioral aspects such as tracking the lanes, following the vehicles, complying with traffic rules, decelerating, accelerating, and intersection crossings. These driver behaviors are parameterized to allow the autonomous agents to act while disregarding the rules (i.e. aggressive behaviors) or behaving normally. The TSS is operated in 3 different modes, namely the orientation, training, and testing modes. During the orientation phase, the candidate driver's target is to get used to the system and the vehicle, along with traffic rules in city conditions. During training, the driver is warned orally (when necessary) and given written handouts about the mistakes that occurred during the training session. The rules to be obeyed in traffic are kept in an XML file in the system and the data are used to follow the driver's behaviors. During the testing phase, an evaluation mechanism is employed. It observes whether the drivers obey or disregard the rules during the testing time interval. At the end of the test drive, a report showing the driver's mistakes is given. The reports and test results can be recorded in the database with the drivers' names for further analysis and evaluation processes. Driver candidates perform the driving using a steering wheel and pedals, along with a screen platform consisting of 3 monitors. With the TSS user interface, parameterized items such as vehicle selection, the crowdedness of the traffic, the timing of the traffic lights, and the determination of air conditions are possible. The system provides a cheap, affordable, and nonrisky platform for the trainees. Test results show that the system improves the drivers' skills and builds trust in them.Öğe An efficient Pseudo microprocessor for engineering education(Elsevier Science Bv, 2012) Gorgunoglu, Salih; Peker, Musa; Sen, Baha; Cavusoglu, AbdullahComputer architecture, computer organization and digital circuits are among the basic topics that are taught in computer sciences and engineering. Because of the degree of abstraction, students often find it difficult to comprehend the subject. Computer architecture and digital circuits are bases for microprocessors and microcontrollers which are widely used in the controlling of the systems in the industry. Therefore, It is necessary to know and understand the structure and programming of the microprocessors in order to be used effectively in applications. In this study, an educational tool for simulating execution of a simple microprocessors commands are presented. This simple microprocessors is in fact an imaginary microprocessors which does not exists commercially. However, it is custom made to fit our educational training purposes. The simulation platform is realized by a visual programming platform. By this study, we have exercised an improvement over the student's understanding of the topics which has been thought in our engineering education classes. (C) 2011 Published by Elsevier Ltd.Öğe Examination of Speed Contribution of Parallelization for Several Fingerprint Pre-Processing Algorithms(Univ Suceava, Fac Electrical Eng, 2014) Gorgunoglu, Salih; Orak, Ilhami Muharrem; Cavusoglu, Abdullah; Gok, MehmetIn analysis of minutiae based fingerprint systems, fingerprints needs to be pre-processed. The pre-processing is carried out to enhance the quality of the fingerprint and to obtain more accurate minutiae points. Reducing the pre-processing time is important for identification and verification in real time systems and especially for databases holding large fingerprints information. Parallel processing and parallel CPU computing can be considered as distribution of processes over multi core processor. This is done by using parallel programming techniques. Reducing the execution time is the main objective in parallel processing. In this study, pre-processing of minutiae based fingerprint system is implemented by parallel processing on multi core computers using OpenMP and on graphics processor using CUDA to improve execution time. The execution times and speedup ratios are compared with the one that of single core processor. The results show that by using parallel processing, execution time is substantially improved. The improvement ratios obtained for different pre-processing algorithms allowed us to make suggestions on the more suitable approaches for parallelization.Öğe Impact of The Ion Channel Blockage on the Collective Spiking Regularity of a Scale-Free Neuronal Network(Elsevier Science Bv, 2012) Yilmaz, Ergin; Ozer, Mahmut; Cavusoglu, AbdullahThe voltage-gated ion channels embedded in biological membranes play crucial roles on the generation and transmission of action potentials. Therefore, understanding of impacts of each ion channel is of great importance for the dynamics of neuronal networks. Among the others, one method on this way is to block a specific ion channel type while keeping the remaining ion channel types active across the membrane and to observe their impact on neuronal dynamics. In this study, we study the effects of sodium and potassium channels blockage on the collective spiking regularity of a scale-free neuronal network with stochastic Hodgkin-Huxley neurons, and investigate how the dependence of the collective spiking regularity on the membrane area or cell size varies with the coupling constant between neurons. Results reveal that the collective spiking regularity exhibits coherence resonance (CR) depending on the channel blockage scaling factor and the cell size, where potassium channel blockage enhances the collective spiking regularity whereas sodium channel blockage decreases it. We show that there is a lower limit for the coupling constant which warrants the CR behavior. We also show that the maximal regularity is obtained for a smaller cell size with the increasing the value of the coupling constant.Öğe Patterns of collaboration in four scientific disciplines of the Turkish collaboration network(Elsevier, 2014) Cavusoglu, Abdullah; Turker, IlkerScientific collaboration networks, as a prototype of complex evolving networks, are studied in many aspects of their structure and evolving characteristics. The organizing principles of these networks also vary in different scientific disciplines, demonstrating that each discipline has specific connecting rules. Retrieving the co-authorship data from the ISI Web of Science, we constructed networks of four disciplines (engineering, mathematics, physics and surgery) as a subset of the Turkish scientific collaboration network spanning 33 years' data, To provide a comparative perspective on the network topologies, we studied some statistical and topological properties such as the number of authors, degree distributions, authors per paper and papers per author histograms and distributions. These properties yield that the rapid growth of high education in Turkey (i.e. doubling of the number of universities and students within the last decade) had boosted the number of publications and increased the level of collaborations in the scientific collaboration networks. We showed the occurrence of Matthew effect in career longevity distributions, and also outlined the Heaps' law relation in the scaling of the collaborations as well. We outlined the prominent properties of each subset, while the similarities and deviations from the interdisciplinary networks are also evaluated. (C) 2014 Elsevier B.V. All rights reserved.Öğe Real-time motorized electrical hospital bed control with eye-gaze tracking(Tubitak Scientific & Technological Research Council Turkey, 2016) Aydin Atasoy, Nesrin; Cavusoglu, Abdullah; Atasoy, FerhatPatients with motor neuron disease and most terminal patients cannot use their hands or arms, and so they need an other person for their all needs. However, the mental functions and memories of such patients are generally sound, and they can control their eyes. Using an eye-gaze tracking technique, we have realized a real-time system for such patients. The system controls a motorized electrical hospital bed (EHB) by eye gaze with 4 degrees of freedom, using a low-cost webcam. Contactless systems that require calibration cannot be used for EHB control. The system developed in this work does not require any calibration process and it is contactless. These properties are the most innovative part of the proposed approach. To begin, the system detects the eye region and computes their is centers. It then tracks the centers and moves a mouse pointer on a screen with the eye gaze. The specific movements of the mouse pointer are evaluated asposition changing request sand the completed movements of the mouse pointer change the EHB position electrically. The communication between the computer and the EHB is provided by a relay control card driven by Arduino Mega. The system work sunder day/artificial lighting conditions successfully with or without eye glasses. The system was tested with 30 volunteers on the EHB safely and was completed with 90% success (the exceptions being people with slanted eyes).Öğe The reforming of vocational teacher training colleges in Turkey(Inderscience Enterprises Ltd, 2011) Cavusoglu, Abdullah; Gunay, DurmusIn Turkey, for many decades college level technical education has been in the form of two main tracks: namely the 'Faculty of Engineering' and the 'Faculty of Technical Education'. The Faculties of Engineering are very similar to engineering schools and colleges around the world; they train engineering students. The 'Faculties of Technical Education' are similar to the 'Schools of Applied Sciences' that many European countries have. The graduates of these schools are either employed at high schools as teachers at technical or vocational high schools, self- employed or employed at other governmental organisations as technical staff. Due to the employability problems that the graduates of these schools have faced in recent years and the suggestions made by The Council of the Higher Education of Turkey (CoHE), Turkish parliament has recently took a decision to close down these colleges and open new colleges called 'Faculty of Technology' in November of 2009. According to the CoHE, these new faculties will train engineering students. The graduates of these faculties can also become teachers at the technical or vocational high schools if they get teaching certificate. This paper discusses the content, outlook, and prospects of this recent reform.Öğe The Reforming of Vocational Teacher Training Colleges in Turkey(Springer-Verlag Berlin, 2010) Cavusoglu, Abdullah; Gunay, DurmusIn Turkey, for many decades college level technical education has been in the form of two main tracks: namely the Faculty of Engineering and the Faculty of Technical Education. The Faculties of Engineering are very similar to engineering schools and colleges around the world; they train engineering students. The Faculties of Technical Education are similar to the Schools of Applied Sciences that many European countries have. The graduates of these schools are either employed at high schools as teachers at technical or vocational high schools, self employed or employed at other governmental organizations as technical staff. Due to the employability problems that the graduates of these schools have faced in recent years and the suggestions made by the The Council of the Higher Education of Turkey (CoHE), Turkish parliament has recently took a decision to close down these colleges and open new colleges called Faculty of Technology in November of 2009. According to the CoHE, these new faculties will train engineering students. The graduates of these faculties can also become teachers at the technical or vocational high schools if they get teaching certificate. This paper discusses the content, outlook, and prospects of this recent reform.Öğe Scientific collaboration network of Turkey(Pergamon-Elsevier Science Ltd, 2013) Cavusoglu, Abdullah; Turker, IlkerNetworking via co-authorship is an important area of research and used in many fields such as ranking of the universities/departments. Studying on the data supplied by the Web of Science, we constructed a structural database that defines the scientific collaboration network of the authors from Turkey, based on the publications between 1980 and 2010. To uncover the evolution and structure of this complex network by scientific means, we executed some empirical measurements. The Turkish scientific collaboration network is in an accelerating phase in growth, highly governed by the national policies aiming to develop a competitive higher education system in Turkey. As our results suggest the authors tend to make more number of collaborations in their studies over the years. The results also showed that, node separation of the network slightly converges about 4, consistent with the small world phenomenon. Together with this key indicator, the high clustering coefficient, (which is about 0.75) reveals that our network is strongly interconnected. Another quantity of major interest about such networks is, the degree distribution. It has a power-law tail that defines the network as scale-free. Along with the final values, the time evolutions of the above-mentioned parameters are presented in detail with this work. In a good agreement with the recent studies, our network yields some significant differences especially in growing rate, clustering properties and node separation. In contrast with the recent studies, we also showed that preferring to attach popular nodes result with being a more popular node in the future. (C) 2013 Elsevier Ltd. All rights reserved.
