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Short Waves

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lightbulbAbout this topic
Short waves refer to electromagnetic waves with wavelengths typically ranging from 10 meters to 100 meters, corresponding to frequencies between 3 MHz and 30 MHz. They are utilized in various applications, including radio communication, broadcasting, and amateur radio, due to their ability to reflect off the ionosphere and travel long distances.
lightbulbAbout this topic
Short waves refer to electromagnetic waves with wavelengths typically ranging from 10 meters to 100 meters, corresponding to frequencies between 3 MHz and 30 MHz. They are utilized in various applications, including radio communication, broadcasting, and amateur radio, due to their ability to reflect off the ionosphere and travel long distances.

Key research themes

1. How are short surface waves in the ocean accurately measured and characterized to inform meteorology and coastal engineering?

This research area focuses on the development and refinement of measurement techniques for short surface waves (wind waves) in the ocean, which have wavelengths from meters to hundreds of meters. Accurate measurement is crucial because short waves influence meteorology, coastal safety, navigation, and the development of wave energy harvesting. Researchers strive to understand the spectral properties of waves (in frequency and direction), to analyze wave height statistics (significant wave height, wave period), and to integrate diverse observational techniques like buoys, satellite remote sensing, coastal radars, and microseism analysis. Increasingly, the need to integrate data across multiple platforms to enable consistent wave climate characterization at local and global scales is emphasized.

Key finding: This paper reviews the main techniques for measuring sea waves, including buoys (drifting and moored), satellite observations, coastal radars, shipboard instruments, and microseism analysis. It emphasizes that wave... Read more
Key finding: The study develops a statistical framework that combines short-term individual wave statistics with long-term sea state occurrence frequencies for improved description of joint distributions of significant wave height and... Read more
Key finding: This paper presents a thorough review of wind wave dynamics including the physical processes governing wave growth, nonlinear interactions, dissipation, and their role within the sea state spectrum. It details the historical... Read more

2. What physical mechanisms govern the generation and statistics of extreme short waves (rogue waves) in oceanic seas?

This research cluster investigates the nonlinear dynamics and statistical properties underlying the formation of unusually large amplitude short waves known as rogue waves, which have significant implications for maritime safety and ocean engineering. The focus is on identifying the relative roles of nonlinear modulational instabilities, bound wave nonlinearities, and wave-wave interference in short-crested multidirectional seas, and on quantifying the probability and occurrence statistics of such extreme waves. These studies employ theoretical analyses, numerical simulations, and field data to elucidate the transient nature and generation mechanisms of rogue waves in realistic ocean environments.

Key finding: By analyzing extensive field measurements from multiple European marine locations, this study provides evidence that rogue wave formation is predominantly caused by constructive interference of elementary waves enhanced by... Read more
Key finding: This work analytically studies the time evolution of the excess kurtosis (a measure of deviation from Gaussianity and an indicator of nonlinear focusing and rogue wave formation) in narrow-band ocean wave fields governed by... Read more
Key finding: This paper offers analytical solutions, including solitons, to the long-short wave equation that models coupled nonlinear wave systems, relevant for shallow water waves exhibiting both long and short components. Employing... Read more

3. How do nonlinear internal waves propagate, interact, and impact shallow water environments and coastal dynamics?

This theme encompasses the study of the generation, transformation, stability, and impact of nonlinear internal waves (NLIWs) especially in shallow and intermediate depth waters, including coral reef flats and continental shelves. These waves affect vertical mixing, coastal flooding, and marine infrastructure safety. Research investigates how internal waves behave under variable bathymetry and currents, their parameterization from field data, and their interactions with surface waves and underwater vehicles. Understanding their statistics, physical characteristics, and interactions is vital for accurate modeling of coastal processes and mitigation of hazards.

Key finding: Utilizing detailed in situ measurements and radar data from the SW06 experiment on the New Jersey continental shelf, this study reconstructs three-dimensional temperature fields spanning over a month of nonlinear internal... Read more
Key finding: This paper compares physical characteristics of traveling waves in shallow and intermediate waters using fully nonlinear Serre-Green-Naghdi (SGN) type models and weakly nonlinear Boussinesq models. It highlights significant... Read more
Key finding: Through linear analysis of one-dimensional internal wave propagation in stationary two-layer flows with variable depth and width, the study identifies three classes of inhomogeneous flows that support reflectionless internal... Read more
Key finding: Analyzing a 5-month dataset from Roi-Namur Island, this research classifies very low frequency (VLF, 0.001-0.005 Hz) waves into resonant, standing, progressive-growing, and progressive-dissipative types based on reef flat... Read more
Key finding: By tracking internal solitary waves (ISWs) of large amplitude from deep waters (up to 500 m depth) to the shore near Dongsha Atoll, this study observes shoaling, breaking, and run-up behaviors dependent on wave amplitude and... Read more

All papers in Short Waves

Recensione dell'articolo di Matteo Leone e Nadia Robotti "La spedizione del dirigibile Italia (1928): un capitolo della storia della fisica" inPhys. Perspect. (2025). https://doi.org/10.1007/S00016-025-00338-9
The article deals with the substitution of a dynamic system defined by a corresponding database of Inputs/Outputs using an equivalent fuzzy system that has a similar behavior in terms of inputs and outputs. The main aim of the article is... more
The aim of this work is to design and construct robotic platform that can move in more than 2 directions without rotating itself. The robot should be capable of object tracking based on colour or temperature and in order to that,... more
Prehlasujem, že som prácu: Spracovanie geodát prostredníctvom rozšírenej reality vypracoval samostatne a všetky použité zdroje a informácie uvádzam v zozname použitej literatúry. Súhlasím, aby moja práca bola zverejnená v súlade s § 47b... more
Since its beginning radio has also been used as an instrument of international communication. Broadcast stations sending messages abroad began to appear shortly after the first wireless transmissions were successfully performed with the... more
In HF broadcasting, the transmitters are typically very powerful. In the case of Turkish Radio and Television (TRT), total transmission average power may reach up to 5 MW. Therefore, it is natural to utilize solar panels as a means of... more
In HF broadcasting, the transmitters are typically very powerful. In the case of Turkish Radio and Television (TRT), total transmission average power may reach up to 5 MW. Therefore, it is natural to utilize solar panels as a means of... more
Hodnota statického parametra je premenlivá a závisí od okamžitej hodnoty nezávislej veli iny. Preto sa zavádzajú ešte: diferenciálny parameter P d = ∂f(x, p)/∂ x , prenosový diferenciálny parameter K d = ∂f(x, p)/∂ p. Je zrejmé, že v... more
Import 05/08/2014Táto práca sa zoberá popisom, matematickým odvodením a realizáciou metódy priameho riadenia momentu na synchrónnom motore s permanentnými magnetmi. Počiatočné kapitoly spracúvajú teoretický popis metódy riadenia. Na... more
V článku je prezentovaný laboratórny model hydraulického systému z hľadiska matematicko-fyzikálneho opisu jeho dynamiky a technickej realizácie, ktorá umožňuje overovať rozličné algoritmy identifikácie a riadenia dynamických systémov.... more
To assess ship maneuverability in waves, computations of a ship with heave, roll and pitch motions in oblique wave are presented. The wave drift forces, heave and pitch motions are investigated numerically. The computations are based on... more
Táto práca sa zaoberá možnosťami využitia koncepcie softwarového rádia pre rádioamatérske účely v pásme KV a jej následnej implementácie do vhodne navrhnutého hardwaru. Cieľom je návrh transceiveru schopného pracovať v režimoch AM, FM,... more