This paper explores three groups of time–frequency distributions: the Cohen’s, affine, and reassigned classes of time–frequency representations (TFRs). This study provides detailed insight into the theory behind the selected TFRs belonging to these classes. Extensive numerical simulations were performed with examples that illustrate the behavior of the analyzed TFR classes in the joint time–frequency domain. […]
Laboratory for Information Processing and Pattern Recognition
Assoc. prof. Jonatan Lerga received the Croatian Academy of Sciences and Arts award
Assoc. Prof. Dr. Sc. Jonatan Lerga received an annual award from the Croatian Academy of Sciences and Arts for the highest scientific achievements in 2021 in the field of technical sciences for the work “Advanced Digital Signal Processing and Machine Learning,” containing 28 scientific papers in renowned international journals (13 of which were published in […]
Dr. Sc. Nikola Lopac successfully defended his doctoral dissertation
Dr. Sc. Nikola Lopac successfully defended his doctoral dissertation “Detection of Gravitational-Wave Signals from Time-Frequency Distributions Using Deep Learning” at the University of Rijeka, Faculty of Engineering on the 11th of March 2022. The doctoral dissertation was defended under the supervision of Assoc. Prof. Dr. Sc. Jonatan Lerga.
Improved Parametrized Multiple Window Spectrogram with Application in Ship Navigation Systems
In analyzing non-stationary noisy signals with time-varying frequency content, it’s convenient to use distribution methods in joint, time and frequency, domains. Besides different adaptive data-driven time-frequency (TF) representations, the approach with multiple orthogonal and optimally concentrated Hermite window functions is an effective solution to achieve a good trade-off between low variance and minimized stable bias […]
BlueNavi: A Microservices Architecture-Styled Platform Providing Maritime Information
Traditional methods of marine navigation are undergoing a revolution brought about by the almost universal adoption of the Automatic Identification System (AIS). AIS exchanges a wealth of navigational information among vessels and between ships to shore through Very High Frequency (VHF). With AIS data integrated into the Electronic Chart Display and Information System (ECDIS), the […]
Shipboard Data Compression Method for Sustainable Real-Time Maritime Communication in Remote Voyage Monitoring of Autonomous Ships
Due to the ever-increasing amount of data collected and the requirements for the rapid and reliable exchange of information across many interconnected communication devices, land-based communications networks are experiencing continuous progress and improvement of existing infrastructures. However, maritime communications are still characterized by slow communication speeds and limited communication capacity, despite a similar trend of […]
Detection of Non-Stationary GW Signals in High Noise from Cohen’s Class of Time-Frequency Representations Using Deep Learning
Analysis of non-stationary signals in a noisy environment is a challenging research topic in many fields often requiring simultaneous signal decomposition in the time and frequency domain. This paper proposes a method for the classification of noisy non-stationary time-series signals based on Cohen’s class of their time-frequency representations (TFRs) and deep learning algorithms. We demonstrated […]
Analysis of Cryptography Algorithms Implemented in Android Mobile Application
This paper evaluates the performances of numerous encryption algorithms on mobile devices running the Android operating system. The primary objective of our research was to measure and compare the relative performances of tested algorithm implementations (Data Encryption Standard (DES), 3DES, Advanced Encryption Standard (AES), ChaCha20, Blowfish, and Rivest Cipher 4 (RC4)) on the Android platform. […]
Modeling Uncertainty in Fracture Age Estimation from Pediatric Wrist Radiographs
In clinical practice, fracture age estimation is commonly required, particularly in children with suspected non-accidental injuries. It is usually done by radiologically examining the injured body part and analyzing several indicators of fracture healing such as osteopenia, periosteal reaction, and fracture gap width. However, age-related changes in healing timeframes, inter-individual variabilities in bone density, and […]
Presentation at the conference “Digital Innovation and Technology for People”
Assoc. Prof. Dr. Sc. Jonatan Lerga held a talk on “How is AI Changing Financial Services?” at the conference “Digital Innovation and Technology for People” held in Opatija on the 9th of December 2021.
