Student EEICT 2021

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    Semi-Supervised Approach To Train Captcha Letter Position Detetor
    (Vysoké učení technické v Brně, Fakulta elektrotechniky a komunikačních technologií, 2021) Bostik, Ondrej
    Common Optical Character Recognition (OCR) methods benefit from the fact, that the text is distributedin images in a predictable pattern. This is not the situation with CAPTCHA systems. UtilizingOCR algorithms to overcome common web anti-abuse CAPTCHA systems is therefore a challengingtask. To train a system to overcome any CAPTCHA scheme, an attacker needs a huge dataset ofannotated images. And for some methods, the attacker needs not only the right answers but also anexact position of the character in the CAPTCHA image.Annotate the positions of the object in an image is a time-consuming task. In this paper, we proposea system, which can help to annotate the position of CAPTCHA character with minimal humaninteraction. After annotating a small sample of targeted CAPTCHA images, a YOLO-based regiondetection deep network is used to search for the characters’ locations.
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    Comparison Of Methods For Impulse Response Computation
    (Vysoké učení technické v Brně, Fakulta elektrotechniky a komunikačních technologií, 2021) Karsky, Vilem
    This paper deals with obtaining impulse responses from integer order and fractional ordertransfer functions. There are shown three method how to compute inverse Laplace transform. The firstmethod is based on Mittag-Leffler functions, the second method is formed on generalized Laguerrefunctions and the third method lays on Fourier transform. These methods are also compared on twoexamples.
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    Derivation And Practical Comparison Of Recursive Ls And Tls System Identification Methods
    (Vysoké učení technické v Brně, Fakulta elektrotechniky a komunikačních technologií, 2021) Friml, Dominik
    The least squares (LS) type of methods are the most widely used methods in system identificationdespite their obvious imperfection. Such methods use a regressor, that is supposed not tocontain any error, notwithstanding that it is constructed from measured data. This can be solved byusing the total least squares (TLS) type of methods. Derivation of both batch and recursive methodsof LS and TLS for identification and their practical comparison is presented in this paper
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    Comparison Of Modern Video Codecs For 4k And 8k Video Content
    (Vysoké učení technické v Brně, Fakulta elektrotechniky a komunikačních technologií, 2021) Budáč, Adam
    The purpose of this paper is to compare modern video codecs, that ensure delivery of 4Kand 8K video content in high quality at reasonable bitrates. There are compared three video codecs:HEVC, VVC and the AV1. Video quality assessment is ensured by using four objective video qualitymetrics, which are: PSNR, SSIM, VIF and VMAF. For tests, there were chosen two from total ofseven videosequencies with different parameters: very high resolutions, high framerates, wide rangeof spatial and temporal indexes and 3D and 360° projection.
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    Smart Home Wired Architecture
    (Vysoké učení technické v Brně, Fakulta elektrotechniky a komunikačních technologií, 2021) Sykora, Tomas
    This article deals with the problem of Smart home systems. Electrical installations innew built and older buildings have recently integrated smart devices. These devices use IoT technology,which needs to communicate with each other. This article discusses the possibilities of replacingmost often used wireless communication for a new type of wired based on Industry IoTstandards. Using wired technologies will enhance the system reliability, safety and security. Whatmore it involve reduction of the electromagnetic smog, a potentially health-endangering effect generatedby devices communicating wirelessly at high frequencies.