Michal Kuba - Academia.edu (original) (raw)
Papers by Michal Kuba
Communications - Scientific letters of the University of Zilina, 2013
Communications - Scientific letters of the University of Zilina, 2004
Communications - Scientific letters of the University of Zilina, 2013
Communications - Scientific letters of the University of Zilina, 2004
2017 Conference on Microwave Techniques (COMITE), 2017
Numerical modelling is an important tool for design and simulation of optical components in the o... more Numerical modelling is an important tool for design and simulation of optical components in the optical communication systems. Signal characteristics of active devices, like distributed feedback laser and avalanche photodiode, which can be obtained from simulations, are the key for performance optical systems. Selection of appropriate numerical methods and tools leads to possibility create effective models emulating more sophisticated optical communication configurations. Sufficiently precise and time effective numerical methods are necessary to obtain characteristics compatible with real devices. Equivalent circuit models utilize sets of differential equations. The key output characteristics of the laser and avalanche photodiode are the optical power, instantaneous optical phase and electrical current at the output. Those fundamental characteristics can be utilized for determination of signal to noise ratio, impact impulse response on the bias voltage and time duration of transmitted symbol. To achieve the maximum signal to noise ratio it is necessary to suppress noise of the semiconductor laser and emit light on the maximum output power. It may be achieved when the laser lasing at the wavelength 800 nm for maximal injected current 24 mA. The 80 V reverse-bias voltage near the breakdown voltage allows maximize output electrical current, simultaneously with high bit rates around 25 Gb/s which increase impulse response of photodiode. Carefully controlling of these parameters is possible by optimization of optical communication system performance.
2020 ELEKTRO, 2020
Two algorithms for removal of short cycles in Tanner graphs of parity-check matrices of binary LD... more Two algorithms for removal of short cycles in Tanner graphs of parity-check matrices of binary LDPC codes constructed by Progressive Edge-Growth algorithm are described. These loop-removing algorithms can be used to improve error-correcting performance of existing LDPC codes and achieved results are provided.
Carpathian Journal of Electronic and Computer Engineering, 2017
Several modern error-correcting codes can perform close to the Shannon limit thanks to the turbo ... more Several modern error-correcting codes can perform close to the Shannon limit thanks to the turbo principle applied in their iterative decoding algorithms. In this paper the principle is discussed in relation to LDPC codes and turbo codes. Methods for improvement of both these codes are described, namely removal of short cycles for LDPC codes and trellis termination for turbo codes. Performance of reference LDPC and turbo codes with and without these improvements is simulated and compared.
2013 Federated Conference on Computer Science and Information Systems, 2013
This article deals with universal sequential audio pattern search and sound recognition method. I... more This article deals with universal sequential audio pattern search and sound recognition method. Inspired by classical phoneme-based speech recognition and word spotting systems, where longer speech patterns are formed by sequences of basic speech units, we propose a methodology for creating a finite database of elementary sound models. These models can be arbitrary concatenated into sequences, thus forming a model of the required acoustical pattern or sound event.
2016 39th International Conference on Telecommunications and Signal Processing (TSP), 2016
In this paper we propose two-dimensional cepstrum analysis approach applied in the emotion recogn... more In this paper we propose two-dimensional cepstrum analysis approach applied in the emotion recognition task in continuous space. Experiments has been done on IEMOCAP database which allows emotion recognition in three dimensions: dimension valence, arousal and dominance. Sequence of experiments has been done over whole range of emotions available in the IEMOCAP database. It includes 6 basic emotional states with three additional emotional states. Performance of system based on two-dimensional cepstrum approach is immediate compared with different approaches. For that cause we utilized concept of “bag-of-features”. It includes vast collection of features with final amount of 961 features per vector. Then we selected most appropriate features with Bat Algorithm and Particle Swarm Optimization method. Performance of our system has been evaluated with Pearson correlation coefficient. Results from both systems presented in this contribution show that we achieved better results in dimensio...
Advances in Electrical and Electronic Engineering, 2003
The article gives a review of a research on processing and automatic recognition of speech signal... more The article gives a review of a research on processing and automatic recognition of speech signals (ARR) at the Department of Telecommunications of the Faculty of Electrical Engineering, University of iilina. On-going research is oriented to speech parametrization using 2-dimensional cepstral analysis, and to an application of HMMs and neural networks for speech recognition in Slovak language. The article summarizes achieved results and outlines future orientation of our research in automatic speech recognition.
International Journal of Geomate, 2015
This paper introduces an innovative and economically convenient measurement system that is based ... more This paper introduces an innovative and economically convenient measurement system that is based on a novelty method of installation, operation and remote control technology for ground watertable measurement. The technology is based on TDR (Time Domain Reflectometry) that employ a unique hollow coaxial cable. Installation is performed by CPT/DP penetration testing equipment, which in its nature, is relatively light, versatile, operative, and is not demanding of manpower or machinery. This method brings benefit to currently unreachable sites ex. steep slopes, places with little or no road access, option for setting up additional probes on existing structures etc., as the method doesnt require conventionally truck-mounted drilling rigs. Electronic origin of measurement offer the possibility of probe networking, remote sensing, automatic data acquisition and evaluation through developed software. Proposed measurement system has been laboratory tested, calibrated and installed on variou...
2019 42nd International Conference on Telecommunications and Signal Processing (TSP), 2019
In this article, we present system for dynamic dimensional music emotion recognition (MER) and co... more In this article, we present system for dynamic dimensional music emotion recognition (MER) and comparison of the system efficiency depending on different audio features. Experiments were performed on the database provided within the Emotion in Music task of MediaEva12015 benchmark (EiMME2015). In addition to the baseline features that were defined by the EiMME2015 organizers and included in the development data, we selected two-dimensional cepstral coefficients (TDC), linear prediction (LP) based coefficients, and the group of musical descriptors to evaluate their discriminative properties for recognition of music emotion. The experiments show that a combination of the EiMME2015 baseline features, LP coefficients and proposed set of music features significantly increases system performance for both arousal and valence emotional dimensions.
paper, we present an approach to detect spoken keywords according to a given query, as part of th... more paper, we present an approach to detect spoken keywords according to a given query, as part of the MediaEval benchmark. The proposed approach is based on a concept of modelling the speech query as a concatenation of language-independent quasi- phoneme models, which are derived by unsupervised clustering on various audio data. Since only an initial version of the system is presented, issues concerning further system improvements are also discussed.
Hydrometeors (rain, fog and ice crystals) affect the transmission of electromagnetic signals. Pre... more Hydrometeors (rain, fog and ice crystals) affect the transmission of electromagnetic signals. Previous research showed that alterations in the signal (amplitude and phase) are affected by the composition of the atmosphere, e.g. the presence of hydrometeors. The majority of hydrometeorological detecting methods are based on the attenuation of electromagnetic signals as they penetrate the atmosphere. Novel methods based on monitoring of parameters of the signal appeared in recent time. This article presents the first results from our investigation of how hydrometeors affect the phase differences in signals transmitted by BTS stations. Cell phone operators transmit electromagnetic signals in the 1 GHz frequency band. This paper describes a novel concept of how phase differences between two signals arriving at two different antennas can be used to detect hydrometeors. Although the described concept is assumed to be independent from the signal strength, the analysed signal must be detect...
The paper is focused on the possibilities of using high-level language-Python in the development ... more The paper is focused on the possibilities of using high-level language-Python in the development of IoT applications. Described are the basic features of the MicroPython implementation and its use in the development of peripherals on the STM32 class microcontroller platform, as well as the possibilities of modification and extension of the standard implementation. Further are mentioned terms of code portability, modularity, flexibility, scalability and expandability significant for MicroPython applications.
An integral part of our environment in addition to the surface of the Earth is the adjacent part ... more An integral part of our environment in addition to the surface of the Earth is the adjacent part of the atmosphere, the lower layer of the troposphere. This part of the troposphere has essential influence on weather evolution and information on its condition is an important part of the weather forecasting models. Standard methods of the data acquisition such as radars, satellites and weather stations do not provide information with sufficiently high temporal and spatial resolution. The subject of the article is a method of monitoring the condition of lower layers of the troposphere by passive monitoring and evaluation the parameters of cellular network signals. The elementary theory of an virtual sensor for the atmospheric radio refractive index monitoring and the preliminary results of experimental monitoring of the selected meteorological situation are presented.
The phonemes recognition is one of the fundamental problems in automatic speech recognition. Desp... more The phonemes recognition is one of the fundamental problems in automatic speech recognition. Despite the great progress in speech recognition, discrimination of isolated phonemes is still challenging task due to coarticulation, and great variability in speaking style. The aim of this work is to develop a system for classification of isolated English vowels from the TIMIT dataset. In the paper, the following conventional methods are compared: a) k-Nearest Neighbours approach as a simple nonlinear instance-based classifier b) Gaussian Mixture Model, which belongs to the class of probabilistic acoustical modelling techniques. As a front-end, we applied standard mel-frequency cepstral coefficients with their time derivates. Various experimental methods such as trimming of audio data and cross-validation were used to increase recognition precision and reliability of system evaluation. The developed system will be used as a baseline for comparison with other newer state-of-the-art approac...
An integral part of our environment in addition to the surface of the Earth is the adjacent part ... more An integral part of our environment in addition to the surface of the Earth is the adjacent part of the atmosphere, the lower layer of the troposphere. This part of the troposphere has essential influence on weather evolution and information on its condition is an important part of the weather forecasting models. Standard methods of the data acquisition such as radars, satellites and weather stations do not provide information with sufficiently high temporal and spatial resolution. The subject of the article is a method of monitoring the condition of lower layers of the troposphere by passive monitoring and evaluation the parameters of cellular network signals. The elementary theory of an virtual sensor for the atmospheric radio refractive index monitoring and the preliminary results of experimental monitoring of the selected meteorological situation are presented.
In this paper, an overview of various types of error-correcting codes is present. Three generatio... more In this paper, an overview of various types of error-correcting codes is present. Three generations of forward error correction methods used in optical communication systems are listed and described. Forward error correction schemes proposed for use in future high-speed optical networks can be found in the third generation of codes.
IoT and their industrial implementation aimed at Industry 4.0 is of a major interest among both r... more IoT and their industrial implementation aimed at Industry 4.0 is of a major interest among both research and development professionals. This article deals with the modifications and extensions possibilities of the standard MicroPython implementation on the STM32 platform, as well as the use in the development, implementation and programming of IoT peripherals, creation of custom libraries and custom modules at the hardware level. Discussed are the essentials associated with the development of general IoT application and the MicroPython environment, as a tool for rapid-prototyping of such applications. Portability is ensured thanks to the intensive utilization of HAL (Hardware Abstraction Layer) technology, which allows usage across the entire spectrum of devices with ported MicroPython. Modularity, scalability and extendibility of the application are demonstrated in examples, where the connection of a common LM92 temperature sensor, the control of a microcontroller pin and a DDS (Di...
Communications - Scientific letters of the University of Zilina, 2013
Communications - Scientific letters of the University of Zilina, 2004
Communications - Scientific letters of the University of Zilina, 2013
Communications - Scientific letters of the University of Zilina, 2004
2017 Conference on Microwave Techniques (COMITE), 2017
Numerical modelling is an important tool for design and simulation of optical components in the o... more Numerical modelling is an important tool for design and simulation of optical components in the optical communication systems. Signal characteristics of active devices, like distributed feedback laser and avalanche photodiode, which can be obtained from simulations, are the key for performance optical systems. Selection of appropriate numerical methods and tools leads to possibility create effective models emulating more sophisticated optical communication configurations. Sufficiently precise and time effective numerical methods are necessary to obtain characteristics compatible with real devices. Equivalent circuit models utilize sets of differential equations. The key output characteristics of the laser and avalanche photodiode are the optical power, instantaneous optical phase and electrical current at the output. Those fundamental characteristics can be utilized for determination of signal to noise ratio, impact impulse response on the bias voltage and time duration of transmitted symbol. To achieve the maximum signal to noise ratio it is necessary to suppress noise of the semiconductor laser and emit light on the maximum output power. It may be achieved when the laser lasing at the wavelength 800 nm for maximal injected current 24 mA. The 80 V reverse-bias voltage near the breakdown voltage allows maximize output electrical current, simultaneously with high bit rates around 25 Gb/s which increase impulse response of photodiode. Carefully controlling of these parameters is possible by optimization of optical communication system performance.
2020 ELEKTRO, 2020
Two algorithms for removal of short cycles in Tanner graphs of parity-check matrices of binary LD... more Two algorithms for removal of short cycles in Tanner graphs of parity-check matrices of binary LDPC codes constructed by Progressive Edge-Growth algorithm are described. These loop-removing algorithms can be used to improve error-correcting performance of existing LDPC codes and achieved results are provided.
Carpathian Journal of Electronic and Computer Engineering, 2017
Several modern error-correcting codes can perform close to the Shannon limit thanks to the turbo ... more Several modern error-correcting codes can perform close to the Shannon limit thanks to the turbo principle applied in their iterative decoding algorithms. In this paper the principle is discussed in relation to LDPC codes and turbo codes. Methods for improvement of both these codes are described, namely removal of short cycles for LDPC codes and trellis termination for turbo codes. Performance of reference LDPC and turbo codes with and without these improvements is simulated and compared.
2013 Federated Conference on Computer Science and Information Systems, 2013
This article deals with universal sequential audio pattern search and sound recognition method. I... more This article deals with universal sequential audio pattern search and sound recognition method. Inspired by classical phoneme-based speech recognition and word spotting systems, where longer speech patterns are formed by sequences of basic speech units, we propose a methodology for creating a finite database of elementary sound models. These models can be arbitrary concatenated into sequences, thus forming a model of the required acoustical pattern or sound event.
2016 39th International Conference on Telecommunications and Signal Processing (TSP), 2016
In this paper we propose two-dimensional cepstrum analysis approach applied in the emotion recogn... more In this paper we propose two-dimensional cepstrum analysis approach applied in the emotion recognition task in continuous space. Experiments has been done on IEMOCAP database which allows emotion recognition in three dimensions: dimension valence, arousal and dominance. Sequence of experiments has been done over whole range of emotions available in the IEMOCAP database. It includes 6 basic emotional states with three additional emotional states. Performance of system based on two-dimensional cepstrum approach is immediate compared with different approaches. For that cause we utilized concept of “bag-of-features”. It includes vast collection of features with final amount of 961 features per vector. Then we selected most appropriate features with Bat Algorithm and Particle Swarm Optimization method. Performance of our system has been evaluated with Pearson correlation coefficient. Results from both systems presented in this contribution show that we achieved better results in dimensio...
Advances in Electrical and Electronic Engineering, 2003
The article gives a review of a research on processing and automatic recognition of speech signal... more The article gives a review of a research on processing and automatic recognition of speech signals (ARR) at the Department of Telecommunications of the Faculty of Electrical Engineering, University of iilina. On-going research is oriented to speech parametrization using 2-dimensional cepstral analysis, and to an application of HMMs and neural networks for speech recognition in Slovak language. The article summarizes achieved results and outlines future orientation of our research in automatic speech recognition.
International Journal of Geomate, 2015
This paper introduces an innovative and economically convenient measurement system that is based ... more This paper introduces an innovative and economically convenient measurement system that is based on a novelty method of installation, operation and remote control technology for ground watertable measurement. The technology is based on TDR (Time Domain Reflectometry) that employ a unique hollow coaxial cable. Installation is performed by CPT/DP penetration testing equipment, which in its nature, is relatively light, versatile, operative, and is not demanding of manpower or machinery. This method brings benefit to currently unreachable sites ex. steep slopes, places with little or no road access, option for setting up additional probes on existing structures etc., as the method doesnt require conventionally truck-mounted drilling rigs. Electronic origin of measurement offer the possibility of probe networking, remote sensing, automatic data acquisition and evaluation through developed software. Proposed measurement system has been laboratory tested, calibrated and installed on variou...
2019 42nd International Conference on Telecommunications and Signal Processing (TSP), 2019
In this article, we present system for dynamic dimensional music emotion recognition (MER) and co... more In this article, we present system for dynamic dimensional music emotion recognition (MER) and comparison of the system efficiency depending on different audio features. Experiments were performed on the database provided within the Emotion in Music task of MediaEva12015 benchmark (EiMME2015). In addition to the baseline features that were defined by the EiMME2015 organizers and included in the development data, we selected two-dimensional cepstral coefficients (TDC), linear prediction (LP) based coefficients, and the group of musical descriptors to evaluate their discriminative properties for recognition of music emotion. The experiments show that a combination of the EiMME2015 baseline features, LP coefficients and proposed set of music features significantly increases system performance for both arousal and valence emotional dimensions.
paper, we present an approach to detect spoken keywords according to a given query, as part of th... more paper, we present an approach to detect spoken keywords according to a given query, as part of the MediaEval benchmark. The proposed approach is based on a concept of modelling the speech query as a concatenation of language-independent quasi- phoneme models, which are derived by unsupervised clustering on various audio data. Since only an initial version of the system is presented, issues concerning further system improvements are also discussed.
Hydrometeors (rain, fog and ice crystals) affect the transmission of electromagnetic signals. Pre... more Hydrometeors (rain, fog and ice crystals) affect the transmission of electromagnetic signals. Previous research showed that alterations in the signal (amplitude and phase) are affected by the composition of the atmosphere, e.g. the presence of hydrometeors. The majority of hydrometeorological detecting methods are based on the attenuation of electromagnetic signals as they penetrate the atmosphere. Novel methods based on monitoring of parameters of the signal appeared in recent time. This article presents the first results from our investigation of how hydrometeors affect the phase differences in signals transmitted by BTS stations. Cell phone operators transmit electromagnetic signals in the 1 GHz frequency band. This paper describes a novel concept of how phase differences between two signals arriving at two different antennas can be used to detect hydrometeors. Although the described concept is assumed to be independent from the signal strength, the analysed signal must be detect...
The paper is focused on the possibilities of using high-level language-Python in the development ... more The paper is focused on the possibilities of using high-level language-Python in the development of IoT applications. Described are the basic features of the MicroPython implementation and its use in the development of peripherals on the STM32 class microcontroller platform, as well as the possibilities of modification and extension of the standard implementation. Further are mentioned terms of code portability, modularity, flexibility, scalability and expandability significant for MicroPython applications.
An integral part of our environment in addition to the surface of the Earth is the adjacent part ... more An integral part of our environment in addition to the surface of the Earth is the adjacent part of the atmosphere, the lower layer of the troposphere. This part of the troposphere has essential influence on weather evolution and information on its condition is an important part of the weather forecasting models. Standard methods of the data acquisition such as radars, satellites and weather stations do not provide information with sufficiently high temporal and spatial resolution. The subject of the article is a method of monitoring the condition of lower layers of the troposphere by passive monitoring and evaluation the parameters of cellular network signals. The elementary theory of an virtual sensor for the atmospheric radio refractive index monitoring and the preliminary results of experimental monitoring of the selected meteorological situation are presented.
The phonemes recognition is one of the fundamental problems in automatic speech recognition. Desp... more The phonemes recognition is one of the fundamental problems in automatic speech recognition. Despite the great progress in speech recognition, discrimination of isolated phonemes is still challenging task due to coarticulation, and great variability in speaking style. The aim of this work is to develop a system for classification of isolated English vowels from the TIMIT dataset. In the paper, the following conventional methods are compared: a) k-Nearest Neighbours approach as a simple nonlinear instance-based classifier b) Gaussian Mixture Model, which belongs to the class of probabilistic acoustical modelling techniques. As a front-end, we applied standard mel-frequency cepstral coefficients with their time derivates. Various experimental methods such as trimming of audio data and cross-validation were used to increase recognition precision and reliability of system evaluation. The developed system will be used as a baseline for comparison with other newer state-of-the-art approac...
An integral part of our environment in addition to the surface of the Earth is the adjacent part ... more An integral part of our environment in addition to the surface of the Earth is the adjacent part of the atmosphere, the lower layer of the troposphere. This part of the troposphere has essential influence on weather evolution and information on its condition is an important part of the weather forecasting models. Standard methods of the data acquisition such as radars, satellites and weather stations do not provide information with sufficiently high temporal and spatial resolution. The subject of the article is a method of monitoring the condition of lower layers of the troposphere by passive monitoring and evaluation the parameters of cellular network signals. The elementary theory of an virtual sensor for the atmospheric radio refractive index monitoring and the preliminary results of experimental monitoring of the selected meteorological situation are presented.
In this paper, an overview of various types of error-correcting codes is present. Three generatio... more In this paper, an overview of various types of error-correcting codes is present. Three generations of forward error correction methods used in optical communication systems are listed and described. Forward error correction schemes proposed for use in future high-speed optical networks can be found in the third generation of codes.
IoT and their industrial implementation aimed at Industry 4.0 is of a major interest among both r... more IoT and their industrial implementation aimed at Industry 4.0 is of a major interest among both research and development professionals. This article deals with the modifications and extensions possibilities of the standard MicroPython implementation on the STM32 platform, as well as the use in the development, implementation and programming of IoT peripherals, creation of custom libraries and custom modules at the hardware level. Discussed are the essentials associated with the development of general IoT application and the MicroPython environment, as a tool for rapid-prototyping of such applications. Portability is ensured thanks to the intensive utilization of HAL (Hardware Abstraction Layer) technology, which allows usage across the entire spectrum of devices with ported MicroPython. Modularity, scalability and extendibility of the application are demonstrated in examples, where the connection of a common LM92 temperature sensor, the control of a microcontroller pin and a DDS (Di...