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Publication Metadata only SCORING: Towards Smart Collaborative cOmputing, caching and netwoRking paradIgm for Next Generation communication infrastructures(IEEE, 2022) Hmitti, Zakaria Ait; Ben Ammar, Hamza; Soyak, Ece Gelal; Kardjadja, Youcef; Malektaji, Sepideh; Ali, Soukaina Ouledsidi; Rayani, Marsa; Saqib, Muhammad; Taghizadeh, Seyedreza; Ajib, Wessam; Elbiaze, Halima; Ercetin, Ozgur; Ghamri-Doudane, Yacine; Glitho, Roch; University of Quebec; University of Quebec Montreal; Sabanci University; Concordia University - Canada; Bahcesehir UniversityThe unprecedented increase of heterogeneous devices connected to the Internet, along with tight requirements of future networks, including 5G and beyond, poses new design challenges to network infrastructures. Collaborative computing, caching and communication paradigm together with artificial intelligence have the potential to enable the Next-Generation Networking Infrastructure (NGNI) that is needed to fulfill the stringent requirements of emerging applications. In this paper, we propose the SCORING project vision for reshaping the current network infrastructure towards an NGNI acting as a truly distributed, collaborative, and pervasive system that enables the execution of application-specific tasks and the storage of the related data contents in the Cloud-Edge-Mist continuum with high QoS/QoE guarantees.Publication Metadata only Metaheuristic-based task scheduling for latency-sensitive IoT applications in edge computing(SPRINGER, 2025) Satouf, Aram; Hamidoglu, Ali; Gul, Omer Melih; Kuusik, Alar; Ata, Lutfiye Durak; Kadry, Seifedine; Bahcesehir University; University of Alberta; University of Alberta; Istanbul Technical University; Tallinn University of Technology; Lebanese American UniversityThe increasing amount of data produced by Internet of Things (IoT) devices imposes significant limitations on the resources available in conventional cloud data centers, undermining their capacity to accommodate time-sensitive IoT applications. Cloud-fog computing has emerged as a promising paradigm that extends cloud services to the network edge. However, the distribution of tasks in a cloud-fog environment presents new challenges. Our research paper introduces a semi-dynamic real-time task scheduling system designed explicitly for the cloud-fog environment. This algorithm effectively assigns jobs while minimizing energy consumption, cost, and makespan. An adapted version of the grey wolf optimizer is introduced to optimize task scheduling by considering various criteria such as task duration, resource requirements, and execution time. Our approach outperforms existing methods, such as genetic algorithm, particle swarm optimization, and artificial bee colony algorithm, in terms of makespan, total execution time, cost, and energy consumption.Publication Metadata only A reliable method for data aggregation on the industrial internet of things using a hybrid optimization algorithm and density correlation degree(SPRINGER, 2024) Heidari, Arash; Shishehlou, Houshang; Darbandi, Mehdi; Navimipour, Nima Jafari; Yalcin, Senay; Halic University; Islamic Azad University; Kadir Has University; National Yunlin University Science & Technology; Bahcesehir UniversityThe Internet of Things (IoT) is a new information technology sector in which each device may receive and distribute data across a network. Industrial IoT (IIoT) and related areas, such as Industrial Wireless Networks (IWNs), big data, and cloud computing, have made significant strides recently. Using IIoT requires a reliable and effective data collection system, such as a spanning tree. Many previous spanning tree algorithms ignore failure and mobility. In such cases, the spanning tree is broken, making data delivery to the base station difficult. This study proposes an algorithm to construct an optimal spanning tree by combining an artificial bee colony, genetic operators, and density correlation degree to make suitable trees. The trees' fitness is measured using hop count distances of the devices from the base station, residual energy of the devices, and their mobility probabilities in this technique. The simulation outcomes highlight the enhanced data collection reliability achieved by the suggested algorithm when compared to established methods like the Reliable Spanning Tree (RST) construction algorithm in IIoT and the Hop Count Distance (HCD) based construction algorithm. This proposed algorithm shows improved reliability across diverse node numbers, considering key parameters including reliability, energy consumption, displacement probability, and distance.Publication Metadata only Throughput-maximizing OFDMA Scheduler for IEEE 802.11ax Networks(IEEE, 2020) Kuran, Mehmet Sukru; Dilmac, A.; Topal, Omer; Yamansavascilar, Baris; Avallone, Stefano; Tugcu, Tuna; Bahcesehir University; Bogazici University; University of Naples Federico IIIn this paper, we develop a novel throughput-maximizing OFDMA scheduler for the multi-user MAC framework for the IEEE 802.11ax networks. The scheduler works both in the downlink and uplink directions and assigns resource units to stations using a linear programming technique considering load of each client, possible resource unit configurations, modulation-coding scheme of each client, and ageing factor of each client's load. The performance of the proposed scheduler has been evaluated using the NS3 simulator and compared against the legacy MAC layer mechanism of IEEE 802.11 protocol (i.e., DCF/EDCA). Simulation results show that our proposed throughput-maximizing scheduler increases the total throughput in the network as well as decrease the average end-to-end delay regardless of the number of stations connected to the access point by prioritizing the traffic of clients connected via high modulation-coding schemes.Publication Metadata only Age of Information in G/G/1/1 Systems: Age Expressions, Bounds, Special Cases, and Optimization(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2021) Soysal, Alkan; Ulukus, Sennur; Bahcesehir University; Virginia Polytechnic Institute & State University; University System of Maryland; University of Maryland College ParkWe consider the average age of information in G/G/1/1 systems under two service discipline models. In the first model, if a new update arrives when the service is busy, it is blocked, in the second model, a new update preempts the current update in service. For the blocking model, we first derive an exact age expression for G/G/1/1 systems. Then, using the age expression for G/G/1/1 systems, we calculate average age expressions for special cases, i.e., M/G/1/1 and G/M/1/1 systems. We observe that deterministic interarrivals minimize the average age of G/M/1/1 systems for a given mean interarrival time. Next, for the preemption in service model, we first derive an exact average age expression for G/G/1/1 systems. Then, similar to blocking discipline, using the age expression for G/G/1/1 systems, we calculate average age expressions for special cases, i.e., M/G/1/1 and G/M/1/1 systems. Average age for G/M/1/1 can be written as a summation of two terms, the first of which depends only on the first and second moments of interarrival times and the second of which depends only on the service rate. In other words, interarrival and service times are decoupled. We prove that deterministic interarrivals are optimum for G/M/1/1 systems for a given mean interarrival time. On the other hand, we observe for non-exponential service times that the optimal distribution of interarrival times depends on the relative values of the mean interarrival time and the mean service time. Finally, we propose a simple to calculate upper bound to the average age for the preemption in service discipline.Publication Metadata only A Holistic Methodology for Digital Governance Transition and Measuring Its Effect on Enterprise Companies(ASSOC COMPUTING MACHINERY, 2021) Ozturk, Ediz; Kocak, Taskin; Loukis, E; Macadar, MA; Nielsen, MM; Bahcesehir University; University of Louisiana System; University of New OrleansDigital transformation has become one of the most emphasized issues for organizations today. Organizations have a long way to go in this difficult road. First of all, they should develop and measure their governance skills, and then they need to create the necessary studies in both technological and managerial terms for IT systems to become a value. While doing all these, they should also create a risk management structure with a correct approach by performing consultancy, supervision, and evaluation services completely. In line with this whole process, there are different standards and practices in every field they need to follow. This paper presents a methodology proposition in a general perspective that can be applied end-to-end in the field of digitalization, starting from the governance structure to the IT value-adding strategy. Thanks to this new methodology, it is possible to see many processes such as governance, consultancy, digital transformation, auditing, internal control, which are disconnected from each other, in the big picture and arrange all activities accordingly. With long-term follow-up, the strategic and tactical perspectives of institutions can be created and their progress over time can be followed by this new methodology. This paper performs both qualitative and quantitative measurements of the applications of the new methodology to compare them with existing ones. This methodology introduces a holistic methodology lacking in the market.Publication Metadata only A Research for Measuring the Effects of COVID-19 on Digital Transformation within Enterprise Companies(ASSOC COMPUTING MACHINERY, 2021) Ozturk, Ediz; Kocak, Taskin; Loukis, E; Macadar, MA; Nielsen, MM; Bahcesehir University; University of Louisiana System; University of New OrleansPandemics are not only medical phenomenon, but they also influence people and society in many respects. It has an effect on almost all markets all over the world. COVID-19 pandemic, expressed as change, empowerment, or post-traumatic growth, with several negative consequences as well as positive consequences. It also has the potential for opportunities. Years of change in the way companies do business have resulted from the COVID 19 crisis across all industries and regions. The aim of this research is to examine the relationship between different demographic variables, COVID-19's impact on digital transformation and post-traumatic effects. The article reflects in practical terms on whether and how the COVID-19 emergence in organizations accelerates digital transformation. This study is a descriptive quantitative approach research based on general survey model.Publication Metadata only Multivariate Spatio-temporal Cellular Traffic Prediction with Handover Based Clustering(IEEE, 2022) Tuna, Evren; Soysal, Alkan; Turkcell Turkey; Bahcesehir University; Virginia Polytechnic Institute & State UniversityWe consider an RNN-based traffic volume prediction, which is a critical problem for network slice management and resource allocation in slicing-enabled next generation cellular networks. We propose to use a novel cost function that takes SLA violations into account. Our approach is multivariate and spatio-temporal in three aspects. First, we consider the effects of several other RAN features in a cell besides the traffic volume. Second, we introduce feature vectors based on peak hours of the day and days of the week. Third, we introduce feature vectors based on incoming handover statistics from the neighboring cells. Our results show about 60% improvement over MAE-based univariate LSTM models and about 20% improvement over SLA-based univariate models.Publication Metadata only An experimental and comparative benchmark study examining resource utilization in managed Hadoop context(SPRINGER, 2023) Ozdil, Uluer Emre; Ayvaz, Serkan; Bahcesehir University; Capgemini; Yildiz Technical UniversityTransitioning cloud-based Hadoop frameworks from IaaS to PaaS, which are commercially conceptualized as pay-as-you-go or pay-per-use, often reduces the associated system costs. However, the managed Hadoop systems obscure the inner performance dynamics of the platform and present a black-box behavior to the end-users. The aim of this study was to investigate the resource utilization of current managed Hadoop platforms. Thus, we explored three prominent Hadoop-on-PaaS proposals as they come out-of-the-box and conducted Hadoop-specific workloads using the HiBench Benchmark Suite. During the benchmark executions, the system resource utilization data from the worker nodes were collected and analyzed. The results indicated that the same property specifications among cloud services neither do guarantee similar performance outputs, nor produce consistent results based on different workloads within themselves. We anticipate that the managed systems' architectures and pre-configurations play a crucial role in the performance outcomes.Publication Metadata only BinoVFAR: An Efficient Binocular Visual Field Assessment Method using Augmented Reality Glasses(ASSOC COMPUTING MACHINERY, 2021) Islam, Md Baharul; Sadeghzadeh, Arezoo; Bahcesehir University; Bahcesehir UniversityVirtual Reality (VR)-based Visual Field Assessment (VFA) methods completely isolate the users from the real world, which results in nausea, eye strain, and lack of concentration and patience for the time-consuming test. In this paper, a robust binocular visual field assessment method based on novel Augmented Reality (AR) glasses is presented, namely, BinoVFAR that can simultaneously find the VF of both eyes. In this method, 60 stimuli in an arrangement of 6 rows and 10 columns randomly appear on a white background on the display of the AR glasses. These stimuli are displayed for 2 seconds that continuously change the intensities from light gray to black. Wearing the AR glasses and focusing on the central fixation point, the users are asked to click the clicker by seen a stimulus. The visible stimuli's intensities and positions are recorded in a 6 x 10 matrix based on the users' responses. A bi-cubic interpolation is applied to compute the binocular visual field map (as a 600 x 1000 matrix). A set of experiments (with an average accuracy of 99.93%), including repeatability and reproducibility tests (with an average Intra-class correlation coefficient (ICC) of 99.72%), are conducted to evaluate the BinoVFAR method.