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Edge detection of aerial images using artificial bee colony algorithm
(Selcuk University Faculty of Technology, 2021-11) Yelmenoğlu, Elif Deniz; Akhan Baykan, Nurdan; Taşdemir, Şakir
Edge detection techniques are the one of the best popular and significant implementation areas of the image processing. Moreover, image processing is very widely used in so many fields. Therefore, lots of methods are used in the development and the developed studies provide a variety of solutions to problems of computer vision systems. In many studies, metaheuristic algorithms have been used for obtaining better results. In this paper, aerial images are used for edge information extraction by using Artificial Bee Colony (ABC) Optimization Algorithm. Procedures were performed on gray scale aerial images which are taken from RADIUS/DARPA-IU Fort Hood database. Initially bee colony size was specified according to sizes of images. Then a threshold value was set for each image, which related with images’ standard deviation of gray scale values. After the bees were distributed, fitness values and probability values were computed according to gray scale value. While appropriate pixels were specified, the other ones were being abandoned and labeled as banned pixels therefore bees never located on these pixels again. So the edges were found without the need to examine all pixels in the image. Our improved method’s results are compared with other results found in the literature according to detection error and similarity calculations’. All the experimental results show that ABC can be used for obtaining edge information from images.
Impact of vaccines on the COVID-19 pandemic in Turkey
(2022-06-01) Yelmenoğlu, Elif Deniz; Elmas, Dilara
COVID-19 (coronavirus disease-2019 pandemic continues to threaten public health and this situation is raising great concern all over the world. With the development of different vaccines, it was aimed to end the epidemic and increase community immunity in the past years. The research reduced public anxiety but the extent of the impact of vaccines in the pandemic is should be under investigation. Because the degree of availability of the COVID-19 vaccines was differing both nationally and globally. This makes it important to investigate how effective vaccination is on the epidemic. The main aim of this study is to investigate the possible recovery impact of vaccination on the COVID-19 pandemic in Turkey. In addition, the rates of severe disease during the first 3 doses of vaccination were also examined in this study. The analyses are conducted based on Spearman, Kendall and Pearson's correlation by using the data of the Ministry of Health of the Republic of Turkey. The obtained results showed that there are strong correlations between vaccination and recovery.
İnsansız hava aracı ve Sentinel-2 görüntüleri kullanılarak ayçiçeği haritalamasına dayalı kovan yerleştirme karar destek sistemi
(BZT Turan Publishing House, 2025-12-31) Yelmenoğlu, Elif Deniz; Aydın, Şahin; Çavdaroğlu, Gülsüm Çiğdem; Deniz, Hüseyin; Pajenado, Rex S.; Dilli, Şirin
Ayçiçeği, yüksek nektar üretim kapasitesi nedeniyle gezici arıcılık faaliyetleri açısından stratejik öneme sahip tarımsal bitkilerden biridir. Ayçiçeği ekim alanlarının mekânsal ve zamansal dağılımı, arı kolonilerinin beslenme olanaklarını ve dolayısıyla bal verimini doğrudan etkilemektedir. Bu nedenle, arı kovanlarının uygun alanlara ve doğru zaman dilimlerinde yerleştirilmesi, gezici arıcılığın verimliliği açısından kritik bir karar sürecini oluşturmaktadır. Ancak mevcut uygulamalarda, kovan yer seçimi çoğunlukla arıcıların bireysel deneyimlerine ve sezgisel yaklaşımlarına dayalı olarak gerçekleştirilmekte; uzaktan algılama, görüntü işleme ve mekânsal analiz gibi veri temelli yöntemlerden yeterince yararlanılmamaktadır. Bu durum, potansiyel olarak verim kayıplarına ve kaynakların etkin kullanılmamasına yol açabilmektedir. Bu çalışmada, ayçiçeği yoğunluğunun doğru ve güvenilir biçimde belirlenmesi yoluyla kovan yerleştirme planlamasını desteklemeyi amaçlayan, çok ölçekli bir uzaktan algılama tabanlı karar destek çerçevesi önerilmektedir. Önerilen yaklaşım, saha ölçeğinde yüksek mekânsal çözünürlük sağlayan insansız hava aracı (İHA) görüntüleri ile bölgesel ölçekte geniş alan kapsama imkânı sunan Sentinel-2 uydu görüntülerinin entegrasyonuna dayanmaktadır. Çalışma alanı olarak, Türkiye’nin önemli ayçiçeği üretim merkezlerinden biri olan Kırklareli ili seçilmiş; veri seti, nektar üretiminin en yüksek olduğu ayçiçeği çiçeklenme dönemi dikkate alınarak oluşturulmuştur. Ayçiçeği tespiti, makine öğrenmesi tabanlı Random Forest sınıflandırma yöntemi kullanılarak gerçekleştirilmiş ve geliştirilen model %90,7 genel doğruluk değerine ulaşmıştır. Sınıf bazlı performans değerlendirmelerinde ise, ayçiçeği ekili alanlar ile ayçiçeği olmayan alanlar için F1-skoru her iki sınıf açısından da 0,91 olarak hesaplanmıştır. Bu sonuçlar, modelin hem nektar açısından zengin ayçiçeği alanlarını hem de ayçiçeği bulunmayan bölgeleri güçlü ve dengeli bir şekilde ayırt edebildiğini göstermektedir. Elde edilen ayçiçeği yoğunluk haritaları temel alınarak, ayçiçeği oranının yüksek olduğu alanlar arı kovanı yerleştirilmesi için uygun bölgeler olarak tanımlanmış; ayçiçeği yoğunluğunun düşük olduğu veya hiç bulunmadığı alanlar ise kovan yerleştirilmesine uygun olmayan bölgeler olarak değerlendirilmiştir. Çalışmadan elde edilen bulgular, çok ölçekli uzaktan algılama verilerinin makine öğrenmesi yöntemleriyle bütünleştirilmesinin, gezici arıcılık uygulamalarında veri temelli, güvenilir ve ölçeklenebilir karar destek sistemlerinin geliştirilmesine önemli katkılar sağlayabileceğini ortaya koymaktadır.
Hybridization strategies in swarm intelligence: the case of ABC–FA and ABC–RUN algorithms
(BZT Turan Publishing House, 2025-10-08) Yelmenoğlu, Elif Deniz; Pajenado, Rex S.; Dilli, Şirin
Metaheuristic optimization algorithms have become a very popular field of study in recent years due to their ability to effectively solve complex, multidimensional problems. In this study, the Artificial Bee Colony (ABC), Firefly Algorithm (FA), and Runge–Kutta (RUN) optimization algorithms, known for their good performance among metaheuristic methods, are compared with their hybrid variants ABC_RUN and ABC_FA. Five widely used benchmark functions were selected for performance evaluation, and the performance results of the algorithms were statistically evaluated using the Wilcoxon signed-rank test. Furthermore, convergence curves were generated to show the average performance of the algorithms, and average running times were calculated to examine the balance between accuracy and computational cost. The findings show that hybrid methods provide higher accuracy compared to classical methods, while the RUN algorithm has an advantage in terms of running time. This comparative analysis demonstrates that hybrid approaches can more effectively balance exploration and exploitation, increase global optimization performance, and are applicable to real-world problems.
A novel hybrid RUN-ABC optimization algorithm
(BZT Turan Publishing House, 2025-10-08) Yelmenoğlu, Elif Deniz; Pajenado, Rex S.; Dilli, Şirin
In recent years, with the development of technology, complex and high-dimensional problems have increased. The use of metaheuristic optimization algorithms in solving these complex problems has become an important research area. In this study, a new hybrid RUN-ABC optimization algorithm was developed by combining the RUN (Runge Kutta Optimization) algorithm and the ABC (Artificial Bee Colony) algorithm. By taking into account the powerful exploration capabilities of the ABC algorithm and the efficient exploitation capabilities of the RUN algorithm, the aim was to search for the best solution in a more balanced manner in the search space. Experiments were conducted on five different benchmark functions to evaluate the performance of the hybrid RUN-ABC method. In these experiments, the developed hybrid method ABC and RUN algorithms were compared based on the average best value, standard deviation, and convergence rate. Furthermore, the Wilcoxon signed-rank test (signrank) was applied to measure the performance between the algorithms. The results showed that the developed hybrid RUN-ABC algorithm outperformed both the RUN and ABC algorithms in most cases. The developed method demonstrated impressive performance in terms of achieving a global minimum and the stability of its results. This study demonstrates that the developed hybrid RUN-ABC method can be a powerful alternative and provides a basis for its future use in solving various complex problems.
A geospatial analysis of the parks, emergency assembly areas, and urban green spaces in Izmir districts
(IKSAD Publications, 2024-12-30) Çavdaroğlu, Gülsüm Çiğdem; Günay, Nazan
Ensuring equity in the allocation of public resources is a central objective for planners. In the context of planning, equitable distribution involves strategically placing resources or facilities to maximize accessibility for a diverse range of spatially distinct social groups. Equity in resource distribution has been a focal point of interest across numerous disciplines. The equity mapping method, which utilizes visualization techniques within geographic information systems (GIS), serves as a valuable tool for analyzing the spatial equity in the distribution of public resources. In this study, equity mapping was applied to parks, green spaces, and emergency assembly areas - resources of significant societal importance - to evaluate individual accessibility to these public facilities. The fundamental methodological approach to equity mapping involves overlaying the distribution of accessibility measures with socioeconomic data to analyze spatial variations in equity. This approach relies on spatial univariate, bivariate, or multivariate analysis, which examines the mapped data distributions and spatial patterns to identify and characterize spatial associations. The study answers eight research questions: (1) the number of emergency assembly areas per capita by district, (2) the number of children's playgrounds per capita among the population aged 0-19 by district, (3) the number of fitness areas per capita among the population aged 20 and above by district, (4) the amount of urban green space per capita among the entire population by district, (5) the distance of the nearest emergency assembly area to the district center, (6) the distance of the nearest emergency assembly area to the neighborhood center, (7) the number of parks within reach of the neighborhood center, (8) number of parks within 1 km of buildings on a district basis. Obtained fundamental patterns of inequity in the distribution of focused public resources in the study may help the municipalities better understand the current situation, make plans for the following years and ensure a more equitable distribution of public resources.
An analysis of the effects of external factors on Covid-19 projections
(ICONSOS Publishing House, 2021-05-10) Çavdaroğlu, Gülsüm Çiğdem; Nuhui, Agim; Yılmaz, Baha Ahmet
[No abstract available]
NFC loyal system on the cloud
(IEEE Computer Society, 2013) Coşkun, Vedat; Özdenizci Köse, Büşra; Ok, Kerem; Alsadi, Mohammed
FC (Near Field Communication) technology facilitates mobile phone usage of billions of people throughout the world that offers diverse services ranging from payment and loyalty applications to access keys for offices and houses. NFC technology is one promising technology that have adopted smart card as secure element (SE) to provide a secure area for the execution of multiple applications and storing sensitive data. In this paper, we developed a framework to integrate NFC loyal system onto the cloud. We adapted NFC mobiles together with their SE to the cloud (Infrastructure as a Service - IaaS) using Cloud Computing methodology.
Reviewing the effects of spatial features on price prediction for real estate market: Istanbul case
(IEEE, 2022-09-16) Ecevit, Mert İlhan; Erdem, Zeki; Dağ, Hasan
In the real estate market, spatial features play a crucial role in determining property appraisals and prices. When spatial features are considered, classification techniques have been rarely studied compared to regression, which is commonly used for price prediction. This study reviews spatial features' effects on predicting the house price ranges for real estate in Istanbul, Turkey, in the classification context. Spatial features are generated and extracted by geocoding the address information from the original data set. This geocoding and feature extraction is another challenge in this research. The experiments compare the performance of Decision Trees (DT), Random Forests (RF), and Logistic Regression (LR) classifier models on the data set with and without spatial features. The prediction models are evaluated based on classification metrics such as accuracy, precision, recall, and F1-Score. We additionally examine the ROC curve of each classifier. The test results show that the RF model outperforms the DT and LR models. It is observed that spatial features, when incorporated with non-spatial features, significantly improve the prediction performance of the models for the house price ranges. It is considered that the results can contribute to making decisions more accurately for the appraisal in the real estate industry.
Comparison of choreography vs orchestration based Saga patterns in microservices
(Institute of Electrical and Electronics Engineers Inc., 2022) Aydın, Şahin; Çebi, Cem Berke
Microservice Architecture (MSA) is a design and architecture pattern created to deal with the challenges of conventional software programs in terms of stream processing, highly available flexibility, and infrastructural agility. Despite the many advantages of MSA, designing isolated services using the autonomous Databases per Services paradigm is difficult. We realized that because each microservice will have its repository, ensuring data coherence between databases becomes difficult, especially in reversals, where operations transcend different sites. Distributed networked transactions and rollbacks can be efficiently handled using two-phase commitment methods in hardware virtualization using RDBMS databases. However, these approaches can't be used in micro-services with segregated NoSQL servers. Three issues have been addressed in this study: (i) investigate the implementation of event choreography and orchestration methods for the Saga pattern execution in MSA, (ii) existing reality suggestions on the saga pattern adoption and implementation besides the use cases, and (iii) introduce the disbursed transaction records and rollbacks challenges in isolated No-SQL databases with reliant collections in MSA.
Photogrammetric monitoring of an artificially generated landslide
(Copernicus GmbH, 2011-05-08) Akça, Mehmet Devrim; Gruen, Armin W.; Askarinejad, Amin; Springman, Sarah Marcella
According to pre-planned schedules, a series of two artificial rainfall events were applied to a forested slope in Ruedlingen, northern Switzerland. The experiments were conducted in autumn 2008 and spring 2009, the second of which resulted in mobilising about 130 m3 of debris. Both experiments were monitored by a photogrammetric camera network in order to quantify spatial and temporal changes. A 4-camera arrangement was used for the image acquisition. The cameras operated at a data acquisition rate of circa 8 frames per second (fps). Image measurements were made using the Least Squares image matching method, which was implemented in an in-house developed software package (BAAP) to compute 3D coordinates of the target points. The surface deformation was quantified by tracking the small (ping-pong and tennis) balls pegged into the ground. The average 3D point-positioning precision of ±1.6 cm was achieved in the first experiment and ±1.8 cm in the second experiment.
Realities & constraints of coal from energy and environmental perspectives
(University of Pittsburgh, 2010) Ekinci, Ekrem
[No abstract available]
Primitives of service oriented information system development
(2011) Aydın, Mehmet Nafiz; Yalçınkaya, Tayfun
One can find the long standing problems with conceptual modeling such as model transformation, reusability and agility in the classical information system development (ISD). New approaches may help in overcoming these issues in conventional ISD's problems. The service oriented approach which is one of the promising approaches, brings solutions to some existing problems. By adopting service orientation in ISD - which we call service oriented ISD, one can deal with the aforementioned problems. This study examines the very notion of service in the context of conceptual modeling method. In particular, we show how to support service modeling in terms of guidance (that is, the way of modeling). The proposed modeling support is demarcated along with a method at the foundational level. The paper is a conceptual and work-in-progress paper.
Usability of mobile voting with NFC technology
(Acta Press, 2010) Ok, Kerem; Coşkun, Vedat; Aydın, Mehmet Nafiz
Voting is a method to select one opinion or a person often following discussion, debate or an election campaign. After centuries of paper based voting ballots, electronic voting is used along with various technologies. One of the promising technologies is Near Field Communication (NFC) which allows data transfer between NFC-enabled devices and smart tags within a short distance. In this paper, we have presented a new type of a secure voting system, namely NFC voting, and evaluated the system's usability in a university council election with an executable prototype. Among other findings, we found that NFC voting satisfies electronic voting requirements and further increases the subjective usability of the proposed system.
Automatic XML schema matching
(2009) Kılıç, Yasin Ozan; Aydın, Mehmet Nafiz
As the enterprise systems increasingly use the XML technology in their data presentation, the Enterprise Application Integration is gradually becoming the problem of Xml Schema matching. Different organizations overall need to exchange information which is mainly all in different Xml Schemas and these schemas need to be transformed before an information exchange takes place. Manually transforming different Xml Schemas is a tedious work and this process needs to be done automatically. This is the problem of Automatic Xml Schema Matching. In this paper, an academic literature review will be given on the subject. The article will examine the problems with contemporary solutions while pointing their weaknesses and propose possible solutions to these problems which reduce it to ontological mapping.
NFC loyal: A Beneficial model to promote loyalty on smart cards of mobile devices
(IEEE, 2010) Özdenizci Köse, Büşra; Coşkun, Vedat; Aydın, Mehmet Nafiz; Ok, Kerem
Near Field Communication (NFC) as a new emerging technology currently tries to find a suitable ecosystem. Development of new standards such as secure element, secure channel, as well as Java Card enables creating new ecosystems using a concurrent multi application platform based on Global Platform. We proposed NFC Loyal, which maintains data interaction and data sharing among payment and loyalty applications through our proposed structure, called as Secure Common Domain Management System (SCDM). SCDM as a centralized database management system on the smart card stores valuable iriformation provided by payment applications and shares them with loyalty applications. The direct outcome of using NFC Loyal is the increase in repeat purchases of customers; as well as a business plan among the payment firms, loyalty firms, and the smart card owner. We fully describe the technical including security architectures and background for the SCDM, and explain the details of the proposed model.
Estimation of microstretch elastic moduli by the use of vibrational data
(Springer, 2007) Kırış, Ahmet; İnan, Esin
In the present work, a nonlinear wave theory is used for the estimation of the material properties of a "microstretch" medium. For this purpose a thin plate is considered and triplicate Chebyshev polynomial series are used as admissible functions to ensure the satisfaction of geometric boundary conditions of the plate. The Ritz technique is applied to derive the frequency equation of the microstretch plate and an optimization procedure is performed by minimising the least square "distance" between computed natural frequencies from the energy method and measured natural frequencies. To realize the optimization procedure, a genetic algorithm is used to estimate the elastic moduli of microstretch medium.
Readiness and mindset for IT offshoring: Insights from banking and insurance organizations
(2009-07-13) Aydın, Mehmet Nafiz; de Groot, Jeroen; Van Hillegersberg, Jos
In this research we examine the IT offshore outsourcing (offshoring) practice of a number of leading finance and insurance organizations in the Netherlands. In particular, we investigate the readiness (the state, condition or quality of being ready) and mindset (habits, opinions which affect a person's attitudes) of the organizations for IT offshoring. We examine IT offshoring practice from the process perspective (that is, the dynamics of IT offshoring projects in terms of culture, method use, IT activities, IT governance, knowledge sharing). Among other findings, this research shows that to a greater extent the organizations have realized readiness for method use and mindset for IT activities, and that the overall improvements regarding these aspects have been modest in a two-year period. On the other hand, mindset for dealing with cultural difference has increased while readiness for flexible working, tracking of requirements change, efficient division of work, and systematic communication is still inadequate. Theoretical and practical implications of the findings are further discussed.
Comparison of evolutionary techniques for Value-at-Risk calculation
(Springer-Verlag Berlin, 2007) Uludağ, Gönül; Etaner Uyar, Ayşe Şima; Senel, Kerem; Dağ, Hasan
The Value-at-Risk (VaR) approach has been used for measuring and controlling the market risks in financial institutions. Studies show that the t-distribution is more suited to representing the financial asset returns in VaR calculations than the commonly used normal distribution. The frequency of extremely positive or extremely negative financial asset returns is higher than that is suggested by normal distribution. Such a leptokurtic distribution can better be approximated by a t-distribution. The aim of this study is to asses the performance of a real coded Genetic Algorithm (CA) with Evolutionary Strategies (ES) approach for Maximum Likelihood (ML) parameter estimation. Using Monte Carlo (MC) simulations, we compare the test results of VaR simulations using the t-distribution, whose optimal parameters are generated by the Evolutionary Algorithms (EAs), to that of the normal distribution. It turns out that the VaR figures calculated with the assumption of normal distribution significantly understate the VaR figures computed from the actual historical distribution at high confidence levels. On the other hand, for the same confidence levels, the VaR figures calculated with the assumption of t-distribution are very close to the results found using the actual historical distribution. Finally, in order to speed up the MC simulation technique, which is not commonly preferred in financial applications due to its time consuming algorithm, we implement a parallel version of it.
Design science in NFC research
(IEEE, 2010) Özdenizci Köse, Büşra; Aydın, Mehmet Nafiz; Coşkun, Vedat; Ok, Kerem
Near Field Communication (NFC), as one of the promising technological developments, provides means to short range contactless communication for mobile phones and other devices alike. NFC has become an attractive design science research area for many academicians due to its exploding growth. A better understanding of the current status of NFC research is necessary to identify the gap between theory and practice. In this paper, we evaluate NFC literature from a design science point of view and seven important guidelines of the design science research are employed for evaluating some of the NFC related studies which propose innovative artifacts. Design science perspective of NFC literature gives beneficial guidelines for future studies. This rigorous and holistic literature review with the objective of bringing to the state-of-art in NFC design science research provides advancement of knowledge in NFC research and further research directions.

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