Ahmet Sayar

Ahmet Sayar
Kocaeli University · Department of Computer Engineering

Ph.D.

About

157
Publications
84,906
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974
Citations
Introduction
Ahmet Sayar received M.Sc. in Computer Science (2001) from Syracuse University and PhD in Computer Sci (2009) from Indiana University, USA. He has worked at Los Alamos National Laboratory (New Mexico, USA) and Community Grids Laboratory (Indiana, USA) as a researcher. Since 2010, he is a professor at Computer Engineering Department, Kocaeli University, Turkey. He is currently a Member of Advisory Committee, TUBİTAK (The Scientific And Technological Research Council Of Turkey). He is also a Member of Board of Directors at Kocaeli University Institute of Science and Technology. He is an associate editor for six journals. His current research interests include Distributed Systems, Big Data, Data-Intensive Computing, Geographic Information Systems (GIS) and Exploratory Data Analysis (EDA).
Additional affiliations
March 2021 - present
Kocaeli University
Position
  • Professor
April 2014 - present
Kocaeli University
Position
  • Professor
July 2009 - April 2014
Kocaeli University
Position
  • Professor (Assistant)

Publications

Publications (157)
Article
The digitalization era has brought digital documents with it, and the classification of document images has become an important need as in classical text documents. Document images, in which text documents are stored as images, contain both text and visual features, unlike images. Therefore, it is possible to use both text and visual features while...
Chapter
Full-text available
The Coronavirus, also known as COVID-19, initially surfaced in Wuhan, China, in December of 2019. The virus was one of the most widely discussed subjects on social media. As a result, these social media sources are exposed to and present a variety of viewpoints, beliefs, and feelings. Big data is a significant resource for computer scientists and s...
Chapter
Full-text available
The Internet of Things (IoT) is the concept of connecting the electronic objects we use in our daily lives to the Internet and allowing them to communicate with one another. These devices can collect a large amount of data, monitor objects, reduce workload, and boost efficiency by saving resources. All of these scenarios highlight the significance...
Article
Full-text available
IoT is becoming ubiquitous in industry, homes, cities, literally in every aspect of our daily lives. Securing IoT-based systems is difficult because of deficiencies in the very nature of IoT devices such as limited battery power, processing, and storage, etc. Blockchain is a new approach used to securely record transactions and offers potential sol...
Article
Full-text available
This study provides a method for determining the location information from a photograph taken by an Unmanned Aerial Vehicle (UAV). In today's defense industry, the goal is to design a reliable navigation system that can operate even when the Internet and GPS systems are unavailable. In the proposed system, it is expected that there is an image data...
Conference Paper
Full-text available
In today's industrial and academic research area, the publish/subscribe (pub/sub) communication paradigm is gaining attention. Due to its capacity to decouple communication entities in time, space, and synchronization, it is a useful interaction mechanism for large-scale distributed systems. Rather than interacting directly with one another, servic...
Article
Full-text available
Satellite mosaic images are of huge sizes and, therefore, the stitching process becomes time- and resource-consuming. To overcome this challenge, we propose a MapReduce-based distributed and scalable image stitching framework. In this framework, we first convert all raster images to binary format. Each binary image is compared with other images usi...
Article
Full-text available
Logistic companies rely on heavily Vehicle Tracking Systems (VTS) to provide instant and valuable data about the vehicle’s condition, the cargoes’ statuses, and the trips. The data that is collected from the vehicles and drivers are generally not fully utilized to its full potential other than day-to-day business activities because of the difficult...
Article
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Digital document collections have been created with the transfer of a large number of documents to digital media. These digital archives have provided many benefits to users. As the diversity and size of digital image collections have grown exponentially, it has become increasingly important and difficult to obtain the desired image from them. The...
Article
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The work presented in this paper proposes a novel approach to tracking a specific vehicle over the video streams published by the collaborating traffic surveillance cameras. In recent years, smart, effective transportation systems and intelligent traffic management applications are among the topics that have been given importance by various institu...
Article
Full-text available
In order for traffic management and information systems to provide proper traffic flow, it is necessary to obtain information about traffic with the help of various sensors. In this context, in recent years the use of video cameras in traffic observation and control has become very widespread and actively used. Numerous studies such as license plat...
Article
As autonomous cars and complex features of them grow in popularity, ensuring that analyses and capabilities are reproducible and repeatable has taken on importance in education plans too. This paper describes a reproducible research plan on mini autonomous race car programming. This educational plan is designed and implemented as part of a summer i...
Article
Full-text available
With respect to the mass categorization that is central to most computer operations, there are two types of relevant data which affect speed of assimilation as well as information recall: structured data and unstructured data. Structured data refers to information with a high degree of organization, such that inclusion in a relational database. How...
Conference Paper
Full-text available
Video processing techniques are used in research areas about traffic for many purposes such as measuring traffic density, crash detection, vehicle classification and counting. To control the traffic flow and create a safer environment, vehicle detection, tracking, security lane and wrong way violation detection is achieved with the developed system...
Article
Full-text available
This paper proposes a new approach to solving the scalability problem in stitching and registration of satellite images. The image stitching process is mostly utilized to capture an image of an entire object, whose parts fall in separate but overlapping mosaics. Due to their high resolutions and huge sizes, the stitching of satellite mosaic images...
Article
Full-text available
The polygon covering problem is an important class of problems in the area of computational geometry. There are slightly different versions of this problem depending on the types of polygons to be addressed. In this paper, we focus on finding an answer to a question of whether an orthogonal rectangle, or spatial query window, is fully covered by a...
Chapter
Full-text available
Advanced driving assistance systems (ADAS) could perform basic object detection and classification to alert drivers for road conditions, vehicle speed regulation, and etc. With the advances in the new hardware and software platforms, deep learning has been used in ADAS technologies. Traffic signs are an important part of road infrastructure. So, it...
Chapter
Full-text available
Seismology, which is a sub-branch of geophysics, is one of the fields in which data mining methods can be effectively applied. In this chapter, employing data mining techniques on multivariate seismic data, decomposition of non-spatial variable is done. Then k-means clustering, density-based spatial clustering of applications with noise (DBSCAN), a...
Article
Bu çalışmanın amacı farklı DNA örneklerindeki dizilimlerin benzerlik oranını hesaplamaktır. DNA verilerinin büyüklüklerinin getirdiği işlem hacmini kısaltmak ve performansı arttırmak için,DNA dizileri sıkıştırılıp motif çıkarımı yapıldı. Bunun için LZ Sıkıştırma algoritması kullanıldı. Elde edilen motiflerden her biri sadece bir graf düğümünü ifade...
Chapter
In the last decade, usage of personal smartphones has tremendously increased. Almost everyone is using cell phones, which are communicating with location-aware devices. A large amount of trajectory data is produced from these devices and can be used for information services. One of the key elements in the mining of GPS or mobility data is the stay...
Conference Paper
Carbide volume fraction and size distribution in 100cr6 steel has been studied using experimental and computational methods. Industrial production cycle of bearing steels includes spheroidization and hardening steps results with coarse globular carbides in martensitic matrix. It is well known that coarse precipitates adversely effects fatigue stren...
Conference Paper
Çalışma genelinde büyük graf eşleşmesi için hızlı bir yaklaşık eşleme algoritması olarak önerilen Fast Projected Fixed-Point (FastPFP) algoritması incelenmeye çalışılmıştır. Çalışma sırasında algoritma testi için gerekli olan verinin elde edilmesi aşamasında görüntü işleme kullanılmıştır. Görüntü işleme adımları da ayrıntılı olarak ele alınmıştır....
Conference Paper
zet. Otel rezervasyon yöntemleri gelişen teknoloji ile birlikte sürekli yenilenmektedir. Rezervasyonda en önemli problem kullanıcıların en az para ile en çok memnuniyet verebilecek otellerin tespitidir. Bu tür problemlerin çözümünde son yıllarda gelişen makine öğrenmesi tekniklerinin kullanıldığı görülmektedir. Ancak mevcut sistemler, statik yapıda...
Conference Paper
Full-text available
zet. Görme engelliler hayatta birçok zorlukla karşılaşmaktadır. Kamuoyunda birçok kurum ve kuruluş bu engelleri aşmak için çalışmalar yapsa da maalesef bazı sorunlar hala çözüme kavuşturulmamıştır. Bunlardan birisi de görme engellilerin kaybettikleri veya o an yerini tam kestiremedikleri eşyaları bulamamasıdır. Geliştirilen uygulama mobil cihazlar...
Preprint
Full-text available
Processing and analyzing of massive clinical data are resource intensive and time consuming with traditional analytic tools. Electroencephalogram (EEG) is one of the major technologies in detecting and diagnosing various brain disorders, and produces huge volume big data to process. In this study, we propose a big data framework to diagnose sleep d...
Preprint
Full-text available
We propose a framework stitching of vector representations of large scale raster mosaic images in distributed computing model. In this way, the negative effect of the lack of resources of the central system and scalability problem can be eliminated. The product obtained by this study can be used in applications requiring spatial and temporal analys...
Article
Full-text available
Transport is an important area for urban policies. Urban transport and independent urban mobility. It is very important in providing social and economic opportunities. Accessibility is a driving factor for urban and social development. An accessible urban transportation infrastructure and system for all will enable all individuals in the city to ac...
Conference Paper
Full-text available
Safe autonomous vehicle steering is one of the most difficult aspects of an artificial intelligence system. Therefore, researchers have concentrated on training deep network models from front-facing camera data synchronized with the steering angles. In this study, three different end-to-end deep learning models are developed and the success of thes...
Chapter
Full-text available
Intelligent traffic management systems needs to obtain information about traffic with different sensors to control the traffic flow properly. Traffic surveillance videos are very actively used for this purpose. In this paper, we firstly create a vehicle dataset from an uncalibrated camera. Then, we test Tiny-YOLO real-time object detection and clas...
Article
Full-text available
Örüntü tanıma psikolojiden biyometriye, biyoenformatikten gen ifadelerinin analizine, trafikten hesaplamalı finansa kadar birçok alanda kullanılmaktadır. Optik Karakter Tanıma da bu alanlardan bir tanesidir. Kamu ve özel birçok firma, arşivlerindeki klasörlenmiş verilerini taratarak dijital hale getirmekte ve bunun için emek yoğun çalışmalar yapmak...
Article
Full-text available
In this study we present a two-step map/reduce framework to stitch satellite mosaic images. The proposed system enable recognition and extraction of objects whose parts falling in separate satellite mosaic images. However this is a time and resource consuming process. The major aim of the study is improving the performance of the image stitching pr...
Article
Full-text available
In this paper, we propose distributed feature extraction tool from high spatial resolution remote sensing images. Tool is based on Apache Hadoop framework and Hadoop Image Processing Interface. Two corner detection (Harris and Shi-Tomasi) algorithms and five feature descriptors (SIFT, SURF, FAST, BRIEF, and ORB) are considered. Robustness of the to...
Conference Paper
Full-text available
Video gözetimi; güvenlik, kolluk kuvvetleri ve trafik izleme gibi önemli uygulama alanlarına sahiptir. Araçların tespiti ve sınıflandırılması, AUS'de kullanılabilen trafik istatistiklerinin ve değerli bilgilerin toplanmasında yardımcı olur. Bu çalışmada, gerçek zamanlı araç sınıflandırmasını inceledik ve YOLO gerçek zamanlı nesne sınıflandırma çerç...
Conference Paper
Full-text available
Cyber security is the major concern in today’s highly networked environment and logging is the primary way of tracking compliance with the security policies. However analyzing the massive amount of logs has become a “Big Data” problem. Apache Spark is one of the latest and most notable incarnation of Data Flow Models in cluster computing. In terms...
Conference Paper
Full-text available
Vektörleştirme, piksel formdaki raster görüntülerin çizgi segmentlerine, çoklu çizgi ve poligon formuna dönüştürmeye odaklanmaktadır. Kaynak ve performans problemleri dikkate alınarak çok sayıda raster görüntüyü vektörleştirmek için MapReduce tabanlı HIPI görüntü işleme dağıtık büyük veri arayüzü kullanılmıştır. Apache Hadoop bu çatının çekirdeğind...
Conference Paper
Full-text available
Nokta seti şablonu eşleştirmesi, bilgisayarla görü ve şablon tanıma alanlarında önemli konulardandır. Nokta seti şablonu eşleştirmedeki ana amaç, aynı sahnenin iki görüntüsündeki noktaları eşleştirmektir. Bu çalışmada vektör hale getirilmiş (noktalarla ifade edilen) aynı sahneyi paylaşan görüntülerdeki noktaların eşleştirilmesi MapReduce programlam...
Conference Paper
Full-text available
Traffic management and information systems need to obtain information about traffic with various sensors to control the traffic flow properly. In this context, videos are very actively used in traffic surveillance and control in recent years. With the help of image processing based video surveillance system in traffic management systems, many studi...
Article
Full-text available
Traffic surveillance cameras are widely used in traffic management and information systems. Processing streaming media in real time is resource and time-consuming processes and even impossible to realize in most real-world applications. To overcome the performance problems in such applications, this article introduces a middleware system based on p...
Conference Paper
Full-text available
With the technological development of global positioning and video surveillance systems and extensive utilization of social media platforms, large amounts of trajectories data are captured. Processing and analyzing of moving objects such as people, animals, and vehicles provides valuable information for industrial and academic studies. In this stud...
Conference Paper
Full-text available
Fonolojik gerilik veya bozukluğun tespit edilmesi ve düzeltilmesi bireylerin kişilik üzerlerindeki negatif etkisinin kalkması ve sosyal yaşama entegrasyon açısından önemlidir. Telaffuz bozukluklarında konuşmacılar, normal olarak konuşabilmesine rağmen bazı ses veya ses gruplarını yanlış telaffuz etmekteler. Bu çalışmada mobil tabanlı olarak izole o...
Conference Paper
Full-text available
To define the state of communication, a lot of signaling protocol has been studied by many researchers. In this paper, we firstly focus on a new hybrid optimized signaling protocol, ARCSPXP (ARDIC Cloud Service Platform Extension Protocol), which is specialized to mobile devices which are communicating with cloud based services via its internet con...
Conference Paper
Full-text available
Sosyal medyanın artan kullanımı ve dijital teknolojilerin yaygın olarak kullanımının artmasıyla veriler çok farklı kaynaklardan ve çok değişik tiplerde üretilmeye başlanmıştır. Text verileri, görüntü verileri ve video verileri bunların en genel örnekleridir. Oluşan büyük verilerin depolanması, işlenmesi ve yo-rumlanması çok büyük önem arz etmektedi...
Conference Paper
Full-text available
Unstructured data forms close to 80% of information in the healthcare industry and is growing exponentially. Analyzing and querying of those type of data is not efficient with traditional relational database technologies. In this paper, we propose a distributed and scalable big data framework for querying and analyzing of unstructured clinical data...
Conference Paper
Full-text available
Birçok karmaşık işlemin yapılmasını gerektiren akademik çalışma (maka-le, bildiri vs.) değerlendirme işlemi, çalışmanın uzmanlarca yeterliliğinin, öne-minin ve orijinalliğinin değerlendirilmesi için yapılmaktadır. Akademik çalış-malara alanlarına uygun hakemlerin atanması bu işlemlerden biridir. Akademik çalışma yazarları; çalışmalarını, yapılan ça...
Conference Paper
Full-text available
Trafik yönetim ve bilgi sistemlerinin trafik akışını düzgün bir şekilde sağlayabilmesi için çeşitli algılayıcılar yardımıyla trafikle ilgili bilgileri elde etmesi gerekmektedir. Bu kapsamda, son yıllarda trafik gözlemi ve denetiminde video kameralarının kullanımı çok yaygınlaşmış ve aktif olarak kullanılmaktadır. Bu çalışmada, araç görüntülerinin s...
Chapter
Full-text available
Finding all objects that overlap a given range query is very important in terms of extraction useful information from big spatial data. In this study, in order to be able to realize range query on large amounts of spatial data, three datasets are created with different size and a MapReduce computation model is set up to test scalability of range qu...
Conference Paper
Full-text available
This study proposes a song recommender system. The architecture is based on a distributed scalable big data framework. The recommender system analyzes songs a person listens to most and recommends a list of songs as a playlist. To realize the system, we use Word2vec algorithm by creating vector representations of songs. Word2vec algorithm is adapte...
Conference Paper
Video surveillance systems have been used in various applications such as traffic monitoring, detecting military threats and public safety. In this study, we evaluate real-time performance for BGSLibrary (Background Subtraction Library) algorithms on well-known datasets, which are Background Models Challenge (BMC) and ChangeDetection.
Conference Paper
Full-text available
We propose a framework stitching of vector representations of large scale raster mosaic images in distributed computing model. In this way, the negative effect of the lack of resources of the central system and scalability problem can be eliminated. The product obtained by this study can be used in applications requiring spatial and temporal analys...
Article
Full-text available
Synchronization is a promising approach to solve the consistency problems in replicated distributed file systems. The synchronization can be repeated periodically, with fixed time interval or a time interval which can be adjusted adaptively. In this paper, we propose a policy-based performance efficient distributed file synchronization approach, in...