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Article A Model Proposal To Optimize Bandwidth Usage in Multi-Access Wireless Networks(Univ Osijek, Tech Fac, 2012) Koyuncu, Murat; Gercek, Mehmet Kazim; Information Systems EngineeringDistribution of load among multiple access points, and therefore, optimizing the total throughput is one of the problems of wireless local area networks when there is more than one access point available in the network. It is not easy to balance the load when wireless hosts associate with one access point by using only the Received Signal Strength Indicator (RSSI). In this study, a new model which increases total throughput in a wireless local area network is proposed. The proposed model is mainly based on the prediction of the loads of all the available access points checking both their wireless and Ethernet interfaces and the association to the least loaded one. It is a host-based model and does not require any changes on the network infrastructure. The tests performed on the real wireless local area networks prove the applicability of the proposed model.Article Citation - Scopus: 1Optimizing the Stochastic Deployment of Small Base Stations in an Interleave Division Multiple Access-Based Heterogeneous Cellular Networks(Wiley, 2022) Noma-Osaghae, Etinosa; Misra, Sanjay; Koyuncu, MuratThe use of small base stations (SBSs) to improve the throughput of cellular networks gave rise to the advent of heterogeneous cellular networks (HCNs). Still, the interleave division multiple access (IDMA) performance in sleep mode active HCNs has not been studied in the existing literature. This research examines the 24-h throughput, spectral efficiency (SE), and energy efficiency (EE) of an IDMA-based HCN and compares the result with orthogonal frequency division multiple access (OFDMA). An energy-spectral-efficiency (ESE) model of a two-tier HCN was developed. A weighted sum modified particle swarm optimization (PSO) algorithm simultaneously maximized the SE and EE of the IDMA-based HCN. The result obtained showed that the IDMA performs at least 68% better than the OFDMA on the throughput metric. The result also showed that the particle swarm optimization algorithm produced the Pareto optimal front at moderate traffic levels for all varied network parameters of SINR threshold, SBS density, and sleep mode technique. The IDMA-based HCN can improve the throughput, SE, and EE via sleep mode techniques. Still, the combination of network parameters that simultaneously maximize the SE and EE is interference limited. In sleep mode, the performance of the HCN is better if the SBSs can adapt to spatial and temporal variations in network traffic.Article Citation - WoS: 12Citation - Scopus: 12A Polarity Calculation Approach for Lexicon-Based Turkish Sentiment Analysis(Tubitak Scientific & Technological Research Council Turkey, 2019) Yurtalan, Gökhan; Koyuncu, Murat; Turhan, ÇiğdemSentiment analysis attempts to resolve the senses or emotions that a writer or speaker intends to send across tothe people about an object or event. It generally uses natural language processing and/or artificial intelligence techniquesfor processing electronic documents and mining the opinion specified in the content. In recent years, researchers haveconducted many successful sentiment analysis studies for the English language which consider many words and wordgroups that set emotion polarities arising from the English grammar structure, and then use datasets to test theirperformance. However, there are only a limited number of studies for the Turkish language, and these studies have lowerperformance results compared to those studies for English. The reasons for this can be incorrect translation of datasetsfrom English into Turkish and ignoring the special grammar structures in the latter. In this study, special Turkish wordsand linguistic constructs which affect the polarity of a sentence are determined with the aid of a Turkish linguist, and anappropriate lexicon-based polarity determination and calculation approach is introduced for this language. The proposedmethodology is tested using different datasets collected from Twitter, and the test results show that the proposed systemachieves better accuracy than the previously developed lexical-based sentiment analysis systems for Turkish. The authorsconclude that especially analysis of word groups increases the overall performance of the system significantly.Article Citation - WoS: 3Citation - Scopus: 5Particle Swarm Optimization of the Spectral and Energy Efficiency of an Scma-Based Heterogeneous Cellular Network(Wiley, 2022) Noma-Osaghae, Etinosa; Misra, Sanjay; Ahuja, Ravin; Koyuncu, MuratBackground The effect of stochastic small base station (SBS) deployment on the energy efficiency (EE) and spectral efficiency (SE) of sparse code multiple access (SCMA)-based heterogeneous cellular networks (HCNs) is still mostly unknown. Aim This research study seeks to provide insight into the interaction between SE and EE in SBS sleep-mode enabled SCMA-based HCNs. Methodology A model that characterizes the energy-spectral-efficiency (ESE) of a two-tier SBS sleep-mode enabled SCMA-based HCN was derived. A multiobjective optimization problem was formulated to maximize the SE and EE of the SCMA-based HCN simultaneously. The multiobjective optimization problem was solved using a proposed weighted sum modified particle swarm optimization algorithm (PSO). A comparison was made between the performance of the proposed weighted sum modified PSO algorithm and the genetic algorithm (GA) and the case where the SCMA-based HCN is unoptimized. Results The Pareto-optimal front generated showed a simultaneous maximization of the SE and EE of the SCMA-based HCN at high traffic levels and a convex front that allows network operators to select the SE-EE tradeoff at low traffic levels flexibly. The proposed PSO algorithm offers a higher SBS density, and a higher SBS transmit power at high traffic levels than at low traffic levels. The unoptimized SCMA-based HCN achieves an 80% lower SE and a 51% lower EE than the proposed PSO optimized SCMA-based HCN. The optimum SE and EE achieved by the SCMA-based HCN using the proposed PSO algorithm or the GA are comparable, but the proposed PSO uses a 51.85% lower SBS density and a 35.96% lower SBS transmit power to achieve the optimal SE and EE at moderate traffic levels. Conclusion In sleep-mode enabled SCMA-based HCNs, network engineers have to decide the balance of SBS density and SBS transmit power that helps achieve the desired SE and EE.Article Citation - WoS: 11Citation - Scopus: 12A Comprehensive Assessment Plan for Accreditation in Engineering Education: A Case Study in Turkey(Tempus Publications, 2015) Turhan, Cigdem; Sengul, Gokhan; Koyuncu, Murat; Information Systems Engineering; Software Engineering; Computer EngineeringThis 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-ACElabel, and a full member signatory of Washington 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 Citation - WoS: 3Citation - Scopus: 3Application of Fnbdt/Scip Protocol on Local Area Network and Determination of Limit Values(Gazi Univ, Fac Engineering Architecture, 2010) Dilli, Orkun; Akcam, Nursel; Koyuncu, Murat; Information Systems EngineeringFast progress in technologies affects all the domains as well as the communication systems. Different types of systems or devices are developed and given to the services without losing time. Although these progresses, in general, have positive effects sometimes they may cause some problems. One of these problems is that the different terminal devices based on ISDN, PSTN and IP cannot communicate end-to-end with each other in a seamless secure way. In this study, FNBDT (Future Narrow Band Digital Terminal)/SCIP (Secure Communication Interoperability Protocol) protocol, which is developed for end-to-end secure communication of different terminal devices communicating on different networks, is tested from different perspectives using terminal emulator on IP Networks. These types of study have great importance in terms of providing some feedbacks to the development of FNBDT/SCIP and, as one of the initial work on this topic, this study will contribute to the future works in the area.Article Citation - WoS: 24Citation - Scopus: 40An Inheritance Complexity Metric for Object-Oriented Code: a Cognitive Approach(Springer india, 2011) Misra, Sanjay; Akman, Ibrahim; Koyuncu, MuratSoftware metrics should be used in order to improve the productivity and quality of software, because they provide critical information about reliability and maintainability of the system. In this paper, we propose a cognitive complexity metric for evaluating design of object-oriented (OO) code. The proposed metric is based on an important feature of the OO systems: Inheritance. It calculates the complexity at method level considering internal structure of methods, and also considers inheritance to calculate the complexity of class hierarchies. The proposed metric is validated both theoretically and empirically. For theoretical validation, principles of measurement theory are applied since the measurement theory has been proposed and extensively used in the literature as a means to evaluate the software engineering metrics. We applied our metric on a real project for empirical validation and compared it with Chidamber and Kemerer (CK) metrics suite. The theoretical, practical and empirical validations and the comparative study prove the robustness of the measure.Article Citation - WoS: 3Citation - Scopus: 2Designing Senior Graduation Project Course for Computing Curricula: an Active Learning Approach(Tempus Publications, 2010) Kilic, Hurevren; Kılıç, Hürevren; Koyuncu, Murat; Koyuncu, Murat; Rehan, Mohammad; Rehan, Mohammad; Kılıç, Hürevren; Koyuncu, Murat; Rehan, Mohammad; Computer Engineering; Computer Engineering; Information Systems Engineering; Information Systems Engineering; Computer Engineering; Information Systems EngineeringThis paper proposes an active learning-based design approach to senior graduation project courses for computing curricula. The proposed approach focuses mainly on course requirements including increasing the interaction between instructor and project team members; providing better and fair student/team performance assessment; encouraging students to practise life-cycle driven development; preparing students for role-based team-working; motivating students to communicate with experts from industry and supporting cooperation between students. It is observed that implementation of the proposed approach increases the student course satisfaction level while higher quality student projects are achieved.Article Citation - WoS: 2Citation - Scopus: 4Ronsi: a Framework for Calculating Return on Network Security Investment(Springer, 2023) Barik, Kousik; Misra, Sanjay; Fernandez-Sanz, Luis; Koyuncu, MuratThis competitive environment is rapidly driving technological modernization. Sophisticated cyber security attacks are expanding exponentially, inflicting reputation damage and financial and economic loss. Since security investments may take time to generate revenues, organizations need more time to convince top management to support them. Even though several ROSI techniques have been put out, they still need to address network-related infrastructure. By addressing gaps in existing techniques, this study delivers a comprehensive framework for calculating Return on Network Security Investment (RONSI). The proposed framework uses a statistical prediction model based on Bayes' theorem to calculate the RONSI. It is validated by Common Vulnerability Security Systems (CVSS) datasets and compared to existing studies. The results demonstrate that the annual loss is reduced to 75% with the proposed RONSI model after implementing a security strategy, and the proposed model is compared with existing studies. An organization can effectively justify investments in network-related infrastructure while enhancing its credibility and dependability in the cutthroat marketplace.Article Fnbdt/scıp Protokolünün Yerel Alan Ağında Uygulanması ve Sınır Değerlerin Tespit Edilmesi(2010) Dilli, Orkun; Akçam, Nursel; Koyuncu, MuratTeknolojideki hızlı değişim her alanda olduğu gibi haberleşme sistemlerinde de yaşanmaktadır. Geliştirilen farklı sistemler veya cihazlar zaman kaybedilmeden kullanıma sunulmaktadır. Söz konusu değişim genelde olumlu olmakla birlikte bazen olumsuz sonuçlara da yol açabilmektedir. Bu olumsuz sonuçlardan bir tanesi, ISDN, PSTN ve IP tabanlı haberleşme cihazlarının birbirleriyle uçtan uca güvenli olarak haberleşme yapamamasıdır. Bu çalışmada, farklı haberleşme ağları üzerinde uçtan uca emniyetli haberleşmenin yapılması amacıyla geliştirilen FNBDT (Future Narrow Band Digital Terminal)/SCIP (Secure Communication Interoperability Protocol) protokolü, emulatörler vasıtasıyla IP ağ üzerinde değişik açılardan test edilmiştir. Bu tür çalışmaların yapılmasının FNBDT/SCIP protokolünün gelişimine katkıda bulunmak açısından büyük önem arz etmekte olduğu ve sunulan çalışmanın bu alanda gerçekleştirilmiş ilk çalışmalardan birisi olması nedeniyle de gelecekte konuyla ilgili yapılacak çalışmalara katkı sağlayacağı düşünülmektedir.
