Arama Sonuçları

Listeleniyor 1 - 8 / 8
  • Yayın
    An endoscopie imaging system based on a two-dimensional CMUT array: real-time imaging results
    (IEEE, 2005) Wygant, Ira O.; Zhuang, Xuefeng; Yeh, David T.; Vaithilingam, Srikant; Nikoozadeh, Amin; Oralkan, Ömer; Ergün, Arif Sanlı; Karaman, Mustafa; Khuri-Yakub, Butrus Thomas
    Real-time catheter-based ultrasound imaging tools are needed for diagnosis and image-guided procedures. The continued development of these tools is partially limited by the difficulty of fabricating two-dimensional array geometries of piezoelectric transducers. Using capacitive micromachined ultrasonic transducer (CMUT) technology, transducer arrays with widely varying geometries, high frequencies, and wide bandwidths can be fabricated. A volumetric ultrasound imaging system based on a two-dimensional, 16×l6-element, CMUT array is presented. Transducer arrays with operating frequencies ranging from 3 MHz to 7.5 MHz were fabricated for this system. The transducer array including DC bias pads measures 4 mm by 4.7 mm. The transducer elements are connected to flip-chip bond pads on the array back side with 400-?m long through-wafer interconnects. The array is flip-chip bonded to a custom-designed integrated circuit (IC) that comprises the front-end electronics. Integrating the front-end electronics with the transducer array reduces the effects of cable capacitance on the transducer's performance and provides a compact means of connecting to the transducer elements. The front-end IC provides a 27-V pulser and 10-MHz bandwidth amplifier for each element of the array. An FPGA-based data acquisition system is used for control and data acquisition. Output pressure of 230 kPa was measured for the integrated device. A receive sensitivity of 125 mV/kPa was measured at the output of the amplifier. Amplifier output noise at 5 Mhz is 112 nV/?Hz. Volumetric images of a wire phantom and vessel phantom are presented. Volumetric data for a wire phantom was acquired in real-time at 30 frames per second.
  • Yayın
    Optimisation of pedestrian detection system using FPGA-CPU hybrid implementation for vehicle industry
    (Inderscience Enterprises Ltd., 2019) Özcan, Ahmet Remzi; Tavşanoǧlu, Ahmet Vedat
    Improved image processing and developing technologies are rapidly expanding the application areas of image processing systems. In recent years, pedestrian detection systems have become one of the major safety technologies used in the automotive industry. This paper presents an optimised real-time pedestrian detection system using an FPGA-CPU based hybrid design. The histograms of oriented gradients (HOG) algorithm, which is extensively used for feature extraction in pedestrian detection applications, was implemented on a low-end FPGA. In the study, the original HOG descriptors are designed in low complexity without sacrificing performance. The obtained features were classified on a low-power single board computer with support vector machine (SVM). Tests with the INRIA pedestrian database show that the proposed model has high potential for use as a real-time low-cost pedestrian detection system in practice.
  • Yayın
    ViLDAR-Visible light sensing-based speed estimation using vehicle headlamps
    (IEEE, 2019-11) Abuella, Hisham; Miramirkhani, Farshad; Ekin, Sabit; Uysal, Murat; Ahmed, Samir
    The introduction of light emitting diodes (LED) in automotive exterior lighting systems provides opportunities to develop viable alternatives to conventional communication and sensing technologies. Most of the advanced driver-assist and autonomous vehicle technologies are based on Radio Detection and Ranging (RADAR) or Light Detection and Ranging (LiDAR) systems that use radio frequency or laser signals, respectively. While reliable and real-time information on vehicle speeds is critical for traffic operations management and autonomous vehicles safety, RADAR or LiDAR systems have some deficiencies especially in curved road scenarios where the incidence angle is rapidly varying. In this paper, we propose a novel speed estimation system so-called the Visible Light Detection and Ranging (ViLDAR) that builds upon sensing visible light variation of the vehicle's headlamp. We determine the accuracy of the proposed speed estimator in straight and curved road scenarios. We further present how the algorithm design parameters and the channel noise level affect the speed estimation accuracy. For wide incidence angles, the simulation results show that the ViLDAR outperforms RADAR/LiDAR systems in both straight and curved road scenarios.
  • Yayın
    Semantic communications in networked systems: a data significance perspective
    (IEEE, 2022-07-01) Uysal, Elif; Kaya, Onur; Ephremides, Anthony; Gross, James; Codreanu, Marian; Popovski, Petar; Assaad, Mohamad; Liva, Gianluigi; Munari, Andrea; Soret, Beatriz; Soleymani, Touraj; Johansson, Karl Henrik
    We present our vision for a departure from the established way of architecting and assessing communication networks, by incorporating the semantics of information for communications and control in networked systems. We define semantics of information, not as the meaning of the messages, but as their significance, possibly within a real time constraint, relative to the purpose of the data exchange. We argue that research efforts must focus on laying the theoretical foundations of a redesign of the entire process of information generation, transmission and usage in unison by developing: advanced semantic metrics for communications and control systems; an optimal sampling theory combining signal sparsity and semantics, for real-time prediction, reconstruction and control under communication constraints and delays; semantic compressed sensing techniques for decision making and inference directly in the compressed domain; semantic-aware data generation, channel coding, feedback, multiple and random access schemes that reduce the volume of data and the energy consumption, increasing the number of supportable devices. This paradigm shift targets jointly optimal information gathering, information dissemination, and decision making policies in networked systems.
  • Yayın
    Architecture of a fully pipelined real-time cellular neural network emulatort
    (IEEE-INST Electrical Electronics Engineers Inc, 2015-01) Yıldız, Nerhun; Cesur, Evren; Kayaer, Kamer; Tavşanoğlu, Ahmet Vedat; Alpay, Murathan
    In this paper, architecture of a Real-Time Cellular Neural Network (CNN) Processor (RTCNNP-v2) is given and the implementation results are discussed. The proposed architecture has a fully pipelined structure, capable of processing full-HD 1080p@60 (1920 1080 resolution at 60 Hz frame rate, 124.4 MHz visible pixel rate) video streams, which is implemented on both high-end and low-cost FPGA devices, Altera Stratix IV GX 230, and Cyclone III C 25, respectively. Many features of the architecture are designed to be either pre-synthesis configurable or runtime programmable, which makes the processor extremely flexible, reusable, scalable, and practical.
  • Yayın
    Range sensing with a Scheimpflug camera and a CMOS sensor/processor chip
    (IEEE-INST Electrical Electronics Engineers Inc, 2004-02) Çilingiroğlu, Uğur; Chen, Sicheng; Çilingiroğlu, Emre
    An image-based range-sensing technique is presented. The technique is originally considered for highway collision avoidance applications, but its generality makes it suitable for application in robotics, manufacturing, and metrology, as well. It relies on depth from focus but, unlike conventional techniques, it extracts range with a single unmodulated Scheimpflug camera in continuous time. The range extraction algorithm is memoryless and simple enough to be implemented on the same chip with photosensors. The technique deploys a sensor plane that is tilted at a nonorthogonal angle with respect to the optical axis of the lens and the optical axis intersects the sensor plane at the focal point. This optical arrangement creates a focusable object plane in an orientation parallel to the optical axis and, thus, enables range sensing along the same axis. This paper elaborates on the details of focus sensing on the tilted sensor plane, describes the CMOS sensor/processor chip designed and prototyped for this application, and presents experimental results.
  • Yayın
    Computer assisted sperm motility analysis implemented on hybrid CPU+FPGA architecture as an intelligent microscope application
    (IEEE Computer Society, 2016) Şavkay, Osman Levent; Yalçın, Müştak Erhan; Tavşanoğlu, Ahmet Vedat
    In this paper we present a Computer Assisted Semen Analysis (CASA) system which is designed and implemented on a hybrid CPU+FPGA architecture platform. The sperm motility analysis deals with the dynamics of sperm movements, thus requires video analysis. A 1280x960 pixel, up to 30 fps programmable camera is used and attached to a trinocular microscope and a PC is used as an HMI and for post calculations, data logging and reporting. The proposed system enables real-time image processing and hence a fast analysis environment, which is important for sperm analysis. In this way we achieved a reconfigurable, reprogrammable, adaptable and extendible system, which can be interpreted as an intelligent microscope.
  • Yayın
    A review of recent innovations in remote health monitoring
    (Multidisciplinary Digital Publishing Institute (MDPI), 2023-12) Dalloul, Ahmed Hany; Miramirkhani, Farshad; Kouhalvandi, Lida
    The development of remote health monitoring systems has focused on enhancing healthcare services’ efficiency and quality, particularly in chronic disease management and elderly care. These systems employ a range of sensors and wearable devices to track patients’ health status and offer real-time feedback to healthcare providers. This facilitates prompt interventions and reduces hospitalization rates. The aim of this study is to explore the latest developments in the realm of remote health monitoring systems. In this paper, we explore a wide range of domains, spanning antenna designs, small implantable antennas, on-body wearable solutions, and adaptable detection and imaging systems. Our research also delves into the methodological approaches used in monitoring systems, including the analysis of channel characteristics, advancements in wireless capsule endoscopy, and insightful investigations into sensing and imaging techniques. These advancements hold the potential to improve the accuracy and efficiency of monitoring, ultimately contributing to enhanced health outcomes for patients.