WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7150

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Now showing 1 - 10 of 31
  • Article
    Citation - WoS: 4
    Citation - Scopus: 3
    Papercraft Doppler Radar Measurements Based on Covariance Eigenvalue Spectrum-Assisted Empirical Mode Decomposition
    (Institute of Electrical and Electronics Engineers Inc., 2025) Atac, Enes; Onay, Fatih; Karatay, Anil
    Doppler radar systems encounter challenges due to their high costs, cumbersome designs, and heavy weights, especially in resource-limited environments. As a promising alternative, papercraft Doppler radar has emerged, offering a lightweight, easily deployable and cost-effective solution. However, despite many advantages, papercraft-based radar faces inherent challenges due to the material used, which leads to vulnerability to external stimuli. In this article, a novel method is proposed demonstrating that papercraft Doppler radar can achieve high performance comparable to its aluminum counterparts and perform multitarget detection even in noisy environment with multiple stimuli. For the first time, we integrate a papercraft Doppler radar with the proposed covariance eigenvalue spectrum (CES)-assisted empirical mode decomposition (EMD) method, significantly improving the performance of the papercraft radar system. Single and multitarget detection, exploiting proper intrinsic mode function (IMF) selection, is achieved through the CES algorithm, which distinguishes between the target and unwanted components via proper windowing and weighting of the decomposed radar signal. According to the results, the proposed method significantly enhances multitarget movement detection and outperforms existing methods.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Practical and Cost-Effective Approach for Thermal Light Characterization Based on Confined Area Measurements
    (Institute of Electrical and Electronics Engineers Inc., 2025) Atac, Enes; Dinleyici, Mehmet Salih
    Photon statistics and optical coherence measurements are essential in understanding light sources' properties and behaviors. However, the measurement setups require sophisticated detectors with short integration times. Otherwise, the results are indeed time average, which poses a significant challenge, particularly for thermal light sources due to their very short coherence times. In this article, we present a novel, practical, and low-cost measurement procedure for characterizing photon statistics and the second-order coherence function of thermal light using an ordinary charge-coupled device (CCD) camera. We focus on single-pixel analysis through the experiments since measurements of randomly distributed light in a confined region follow Bose-Einstein statistics. This way, the likelihood of averaging during detection is reduced, allowing us to extract statistical information from the spatially distributed intensity values. The outcomes prove the effectiveness of confined area measurements method by overcoming the detector's long exposure time issue.
  • Conference Object
    Community Detection for Large Graphs on GPUs With Unified Memory
    (Institute of Electrical and Electronics Engineers Inc., 2024) Dincer, Emre; Öz, Işıl; Oz, Isil
    While GPUs accelerate applications from different domains with different characteristics, processing large datasets gets infeasible on target systems with limited device memory. Unified memory support makes it possible to work with data larger than available GPU memory. However, page migration overhead for executions with irregular memory access patterns, like graph processing workloads, induces severe performance degradation. While memory hints help to deal with page movements by keeping data in suitable memory spaces, coarse-grain configurations can still not avoid migrations for executions having diverse data structures. In this work, we target the state-of-the-art CUDA implementation of the Louvain community detection algorithm and evaluate the impacts of the fine-grained unified memory hints on the performance. Our experimental evaluation shows that memory hints configured for specific data structures reveal significant performance improvements and enable us to work efficiently with large graphs.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 1
    Toward Cost-Effective and Lightweight Doppler Radars: Papercraft-Based Components and Comparisons With Aluminum and 3-D Printed Alternatives
    (Institute of Electrical and Electronics Engineers Inc., 2024) Karatay,A.; Atac,E.; Yaman,F.
    Doppler radar systems have an essential role in various applications, including aviation, weather forecasting, and military surveillance. However, their high fabrication costs and heavy weight may limit their utilization in rapid prototyping, small-scale applications, and seamless transportation. To address these challenges, a novel papercraft-based approach for producing the entire Doppler radar system's horn antenna, hybrid tee, and short termination components in the X-band was investigated with details in this study, alongside conventional aluminum and 3-D printing methods. This article presents the first attempt to develop a Doppler radar using papercraft-based manufacturing. The papercraft-based approach is cost-effective, lightweight, flexible, and readily available, offering a promising route for improving and fabricating Doppler radar systems that are both affordable and accessible, particularly in resource-limited settings. The experimental results show that the papercraft-based components can perform comparably to conventional aluminum-based and 3-D-printed components, making it an innovative and cost-effective solution for fabricating Doppler radar systems. © 2023 IEEE.
  • Conference Object
    Citation - WoS: 2
    Citation - Scopus: 3
    Adopting Heterogeneous Computing Modules: Experiences From a Touch Summer Workshop
    (Institute of Electrical and Electronics Engineers Inc., 2022) Bunde, D.P.; Ahmed, K.; Ayloo, S.; Brown-Gaines, T.; Fuentes, J.; Jatala, V.; Yeh, T.Y.
    We present efforts to encourage the adoption of modules for teaching heterogeneous parallel computing through a faculty development workshop. The workshop was held remotely using a novel format to exploit the advantages of a virtual format and mitigate its disadvantages. Adoption at a wide variety of institutions showed module effectiveness and also gathered feedback leading to several module improvements. We also report on the adoptions themselves, which show the importance of supporting adaptation of the modules for diverse settings. © 2022 IEEE.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 8
    Coverage Analysis of Physical Layer Network Coding in Massive Mimo Systems
    (Institute of Electrical and Electronics Engineers Inc., 2021) İlgüy, Mert; Özbek, Berna; Mumtaz, Rao; Busari, Sherif A.; Gonzalez, Jonathan
    Wireless networks are prone to interference due to their broadcast nature. In the design of most of the traditional networks, this broadcast nature is perceived as a performance-degrading factor. However, Physical Layer Network Coding (PNC) exploits this broadcast nature by enabling simultaneous transmissions from different sources and thereby enhances the performance of the wireless networks with respect to improvement in spectral efficiency, coverage, latency and security of the system. For fifth generation (5G) networks and beyond, massive multiple input multiple output (MIMO) is considered as a key physical layer technology. Thus, its combination with PNC can significantly enhance the performance of the network, facilitating capacity-coverage improvement, among other benefits. While the bit error rate performance of multiuser massive MIMO-PNC systems through linear detection has been investigated extensively, their coverage probability for a given target signal-to-noise ratio has not been explored yet. In this paper, we derive a closed form expression for coverage probability in PNC based multiuser massive MIMO systems employing zero-forcing equalization. Both theoretical and simulation results are provided for different number of users and antennas in the multiuser massive MIMO-PNC communications systems.
  • Conference Object
    Consistency Analysis of Kalman Filter for Modal Analysis of Structures
    (Institute of Electrical and Electronics Engineers Inc., 2009) Tanyer, İlker; Özen, Serdar; Dönmez, Cemalettin; Altınkaya, Mustafa Aziz
    In this paper, Consistency Analysis of Kalman Filter for Modal Analysis of Structural Systems is made. As a future work, A fundamental Modal Analysis algorithm, Eigensystem Realization Algorithm(ERA) will be used with Kalman filters together to make a modal parameter estimation for a structural system. By applying ERA to the impulse response measurements taken from the structure, a state-space representation will be written. Kalman filter will be used as a state estimator in this study and it will have a critical role on minimizing the measurement noise. Before using Kalman filter with ERA, a consistency analysis of Kalman filter is made for artificial impulse response data of the structural system.
  • Conference Object
    A Study on Nonlinear Photonic Crystal Optical Switching With Chi((3)) Type Material
    (Institute of Electrical and Electronics Engineers Inc., 2009) Karakılınç, Özgür Önder; Dinleyici, Mehmet Salih
    In this study two dimensional square photonic crystal with line defect waveguide and embedded in nonlinear Kerr type dielectric rods are examined. Depending on the number and location of Kerr type nonlinear rods, power flux and harmonics are investigated. Optical switching of carrier signal is performed with using the control signal.
  • Conference Object
    Transmit Beamforming Techniques for Multicast Wireless Communication Systems
    (Institute of Electrical and Electronics Engineers Inc., 2009) Özbek, Berna; Le Ruyet, Didier
    In this paperg transmit beamforming algorithm is designed for multicast wireless communication providing only one beam and multiple beams. The reduced complexity algorithms are imyproved the system performance with multiple transmit beamy forming techniques.
  • Conference Object
    Alpha-Trimmed Means of Multiple Location Estimates
    (Institute of Electrical and Electronics Engineers Inc., 2013) Altınkaya, Mustafa Aziz
    Localization by distance measurements is a common technique for solving this contemporary problem. The methods which achieve the theoretically optimum solutions have generally iterative structures. That is why when limited computational load is required, suboptimum methods described by closed form formulas like the one of Coope which depends on orthogonal decomposition of sensor coordinates, are preferred. In this method, when there are more than necessary distance measurements required for localization, the location will be found as the arithmetic average of the estimates obtained using the all three-combinations of distance measurements. In the averaging, eliminating the outlier estimates will increase the performance. In this case discarding the estimates making the ratio of alpha which are farthest away from the arithmetic average, one attains the socalled alpha-trimmed mean of the estimates. Applying this technique, the disturbing effects of impulsive mixture of Gaussian contamination are eliminated and similar performances as in the case of Gaussian distance measurements are attained in localization.