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Conference Object Citation - WoS: 2CAWP A Combinatorial Auction Web Platform(Scitepress, 2010) Cereci, Ibrahim; Kilic, HurevrenOnline auctions, including online Combinatorial Auctions, are important examples of e-commerce applications. In this paper, a Combinatorial Auction Web Platform (CAWP) is introduced. The platform enables both product selling and buying capabilities that can be realized in a combinatorial way. CAWP supports a Sealed-Bid Single-Unit type of Combinatorial Auctions. Easy customization for any selected problem domain is a distinguished feature of CAWP. Platform users are not expected to have any technical knowledge about how to solve the Winner Determination Problem (WDP) known to be critical for profit maximization of the auctioneers in Combinatorial Auctions.Conference Object An Investigation About Process Matchmaking Performances of Unstructured and Decentralized Digital Environments(Ieee, 2007) Cakir, Bugra; Kilic, HurevrenEfficient matchmaking is an important problem in unstructured and decentralized digital environments. We report the results of simulations of these environments and provide measurements of match performance focusing on unstructured and decentralized environments. In the study, different environment models including P2P (Hypergrid, Gnutella with/without ultrapeer); small-world (Watts-Strogatz); heavy-tailed and random versions of Autonomous System Waxman model showing power-law distribution property; random and 2D-Grid are considered. The flooding mechanism enabling process encounters for match purposes is uninformed Breadth-First-Search. Simulations show that the matchmaking performance of random environment outperforms the others for almost all different problems and time-to-live settings. On the other hand, the total cost of small world environment model is the highest for almost all setups.Conference Object Citation - WoS: 3An Agent-based Trading Infrastructure for Combinatorial Reverse Auctions(Ieee, 2014) Bayindir, Hakan; Kilic, Hurevren; Rehan, MohammedA Combinatorial Reverse Auction Trading Infrastructure - CRATI is designed and implemented as an agent-based system. Two basic building blocks Java Agent Development Framework (JADE) and an Open Source Java Constraint Programming Library (Choco Solver) are used to facilitate agent interactions and an optimization task. For our purpose, it is shown that auction Winner Determination Problem (WDP) can suitably be represented as a weighted set covering problem instance whose solution gives the decided winners of the auction process. In order to realize the system, a variation of Contract Net protocol is designed and implemented to handle auctions that occur in the platform from start to finish.Conference Object F-Actor: a Multiagent Gaming Environment for Controlling Virtual Flow Networks(Univ Wolverhampton, 2008) Ocal, Ilter Kagan; Cevik, Ahmet; Cereci, Ibrahim; Kilic, Hurevren; Computer EngineeringA gaming environment that enables agent-based local control of a configurable virtual flow network is developed. The gaming software what we call F-Actor provides a graph-based discrete virtual control environment on which user-developed controller agents reside and act according to their assigned design goals. Runtime performances of user-developed controller agent codes are made observable through a graphical user interface. The proposed game can be played by different developers having different level of control and programming knowledge. By playing with F-Actor, engineers (or students) can make practices on a virtual flow environment and try alternative intelligent control algorithms before their potential implementations on field.Conference Object Citation - WoS: 6Citation - Scopus: 7Protocol and Connectivity Based Overlay Level Capacity Calculation of P2p Networks(Ieee Computer Soc, 2006) Oztoprak, Kasim; Kilic, HurevrenIn this paper, we proposed a metric for P2P networks based on Shannon's L-channel capacity calculation idea. The metric calculates the maximum rate of information (in bits per second) that can be transmitted over P2P network (a.k.a. combinatorial capacity) caused by protocol and overlay-level connectivity. We suggest P2P systems to be modeled as a discrete noiseless channel on which the protocol together with dynamically changing overlay-level instant connectivity topology defines a Shannon Language. In experimental works, we applied the metric first to the Gnutella 0.6 protocol for which message traffic explosion is a known problem and then to its time-based clustering version. The obtained results are compared with other two known metrics' namely, number of query hits and unit query-hit response time, results and potential correlations among them are discussed.Article Citation - WoS: 3Citation - Scopus: 3Online Learning Perceptions Amid Covid-19 Pandemic: the Engineering Undergraduates' Perspective(Tempus Publications, 2022) Eryilmaz, Meltem; Kalem, Guler; Kilic, Hurevren; Tirkes, Guzin; Topalli, Damla; Turhan, Cigdem; Yazici, Ali; Information Systems Engineering; Computer Engineering; Software EngineeringThe COVID-19 pandemic caused face-to-face education in just about all universities worldwide to shift to online education. For most students, this educational model was a compulsory first experience. In this study, the survey results are analyzed and discussed related to a group of students in the Engineering Faculty of a university in Turkey regarding their online education perceptions. Briefly summarized, the findings of the study indicate that: (a) most of the students still prefer face-to-face learning, which is also favored if accompanied by distance learning; (b) the concentration level of the students has dropped due to the concerns about the COVID-19 pandemic which affects their learning negatively; and (c) around half of the students participating in the study feel that the online exams conducted without a secure exam software, is considered unsafe. Additionally, the study's results were further extended to evaluate the questionnaire results and reported along with the suggestions of necessary actions in emergency online learning (EOL).Conference Object Mobile Prisoner's Dilemma Game Played on Diverse Habitats(Ieee, 2011) Celebi, Remzi; Kilic, HurevrenPromotion of cooperative behavior in Prisoner's Dilemma (PD) game while players that are allowed to move between different gaming environments (i.e. habitats) is investigated. The stochastic mobile model under study is realized over connected habitats that are situated on a two dimensional grid environment. The players appearing in the same habitat are allowed to interact with their immediate neighbors. Mobility of a player is defined as movement from its habitat to another based on both obtained payoff and randomly assigned habitat diversity values. By the end of extensive experimentation, it is concluded that player mobility is an effective factor that contributes to promotion of cooperation in spatial evolutionary games. Also, even for higher values of temptation of PD game, habitat diversity supports and triggers a collective resistance for the emergence and promotion of cooperative system behavior.Article Citation - WoS: 4Citation - Scopus: 5Automata Networks as Preprocessing Technique of Artificial Neural Network in Estimating Primary Production and Dominating Phytoplankton Levels in a Reservoir(Elsevier, 2006) Kilic, Hurevren; Soyupak, Selcuk; Gurbuz, Hasan; Kivrak, ErsinArtificial Neural Networks (ANN) is computational architectures that can be used for estimating primary production levels and dominating phytoplankton species in reservoirs. Automata Networks (AN) were applied as a pre-processing method with subsequent ANN model development for Demirdoven Dam Reservoir. The primary purpose of using preprocessing technique was to distinguish the suitable and appropriate constituents of the input parameters' matrix, to eliminate redundancy, to enhance prediction power and calculation efficiency. The data were collected monthly over two years. The applications have yielded following results: The correlation coefficients (r values) between predicted and observed counts were as high as 0.83, 0.87, 0.83 and 0.88 for Cyclotella ocellata, Sphaerocystis schroeteri, Staurastrum longiradiatum counts, and Chlorophyll-a (Chl-a) concentrations respectively with AN. The performance of AN based pre-processing technique was compared with the performance of a well-known pre-processing technique, namely Principle Component Analysis(PCA), experimentally. r values between the predicted and observed C. ocellata, S. schroeteri and S. longiradiatum counts, and (Chl-a) were as high as 0.80, 0.86, 0.81 and 0.86 respectively with PCA. (c) 2006 Elsevier B.V. All rights reserved.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.Conference Object Citation - WoS: 13Search-Based Parallel Refactoring Using Population-Based Direct Approaches(Springer-verlag Berlin, 2011) Kilic, Hurevren; Koc, Ekin; Cereci, IbrahimAutomated software refactoring is known to be one of the "hard" combinatorial optimization problems of the search-based software engineering field. The difficulty is mainly due to candidate solution representation, objective function description and necessity of functional behavior preservation of software. The problem is formulated as a combinatorial optimization problem whose objective function is characterized by an aggregate of object-oriented metrics or pareto-front solution description. In our recent empirical study, we have reported the results of a comparison among alternative search algorithms applied for the same problem: pure random, steepest descent, multiple first descent, simulated annealing, multiple steepest descent and artificial bee colony searches. The main goal of the study was to investigate potential of alternative multiple and population-based search techniques. The results showed that multiple steepest descent and artificial bee colony algorithms were most suitable two approaches for an efficient solution of the problem. An important observation was either with depth-oriented multiple steepest descent or breadth-oriented population-based artficial bee colony searches, better results could be obtained through higher number of executions supported by a lightweight solution representation. On the other hand different from multiple steepest descent search, population-based, scalable and being suitable for parallel execution characteristics of artificial bee colony search made the population-based choices to be the topic of this empirical study. I In this study, we report the search-based parallel refactoring results of an empirical comparative study among three population-based search techniques namely, artificial bee colony search, local beam search and stochastic beam search and a non-populated technique multiple steepest descent as the baseline. For our purpose, we used parallel features of our prototype automated refactoring tool A-CMA written in Java language. A-CMA accepts bytecode compiled Java codes as its input. It supports 20 different refactoring actions that realize searches on design landscape defined by an adhoc quality model being an aggregation of 24 object-oriented software metrics. We experimented 6 input programs written in Java where 5 of them being open source codes and one student project code. The empirical results showed that for almost all of the considered input programs with different run parameter settings, local beam search is the most suitable population-based search technique for the efficient solution of the search-based parallel refactoring problem in terms of mean and maximum normalized quality gain. However, we observed that the computational time requirement for local beam search becomes rather high when the beam size exceeds 60. On the other hand, even though it is not able to identify high quality designs for less populated search setups, time-efficiency and scalability properties of artificial bee colony search makes it a good choice for population sizes >= 200.
