The motion of fluids is modeled by various systems of partial differential equations, depending on the properties of the fluid, the medium through which it moves, or the space-time scales on which the motion is studied. I will start by discussing two of the most fundamental of these models: the 2D Euler equations modeling motions of ideal fluids, and the incompressible porous media equation...
We study a fluctuation test where cell colonies grow from a single cell to a specified population size before undergoing treatment. During growth, cells may acquire resistance to treatment and pass it to their offspring with a small probability. Unlike the classical Luria–Delbrück test, which assumes irreversible resistance, our model allows resistant cells to revert to a drug-sensitive state....
Určenie veku artefaktov s presnosťou na niekoľko desaťročí v závislosti od veku vzorky, je dnes možné vďaka rádiouhlíkovému datovaniu a použitiu vysokocitlivej urýchľovačovej hmotnostnej spektrometrie. Datovanie pomocou rádiouhlíka využíva koncentráciu 14C na určenie veku vzorky a patrí medzi deštruktívne analytické metódy. Táto metóda v minulosti pomohla s odhaľovaním falzifikátov a ochranou...
Táto práca sa zameriava na využitie programu Algodoo vo vyučovaní fyziky. Algodoo poskytuje učiteľom fyziky možnosť doplniť experimenty realizované na hodinách fyziky počítačovým modelom alebo, v prípade potreby, niektoré experimenty úplne nahradiť, najmä v oblastiach mechaniky a optiky. Súčasťou práce je vytvorenie konkrétnych modelov a aktivít pre žiakov, ktoré podporujú rozvoj ich zručností...
A computer transmits visual information to a monitor as a continuous stream of RGB pixels, with their intensities encoded as voltage levels in the signal traveling through the video cable. The high-frequency voltage transitions of the signals generate unintentional electromagnetic emissions, which can be intercepted and used to reconstruct the displayed image. Under standard conditions, using...
Human--robot interaction requires robots whose actions are legible, allowing humans to interpret, predict, and feel safe around them. This study investigates the legibility of humanoid robot arm movements in a pointing task, aiming to understand how humans predict robot intentions from truncated movements and bodily cues. We designed an experiment using the NICO humanoid robot, where...
We study a fluctuation test where cell colonies grow from a single cell to a specified population size before undergoing treatment. During growth, cells may acquire resistance to treatment and pass it to their offspring with a small probability. Unlike the classical Luria–Delbrück test, which assumes irreversible resistance, our model allows resistant cells to revert to a drug-sensitive state....
V práci sa navrhuje konceptuálny model výučby fyziky založený na integrácii teórie skefoldingu a adaptovanej Rumsfeldovej matice. Výskum chápe edukačný proces ako cyklický pohyb žiaka cez štyri kognitívne stavy – od nevedomého nepoznania až k intuitívnemu ovládaniu poznatkov. Model opisuje mechanizmus postupného oslabovania pedagogickej podpory a formovania autonómnych stratégií poznávacej...
The light reflected from the surface of solid celestial bodies like asteroids contains information about chemical composition, physical and structural properties of their near-surface material. Measurements of this reflected light through different broadband photometric filters enable us to study color properties of minor bodies. Color-color diagrams, constructed from photometric color...
The paper presents the results of an analysis of the performance of pupils who participated in the international rounds of the International Junior Science Olympiad (IJSO) in 2023 and 2024 (six pupils each year). The aim of the analysis was to find out how the selected sample of Slovak pupils performed in standardized tests, more precisely – to what extent the pupils lacked the ability to use...
Space weathering impacts all objects exposed to the space environment, including artificial satellites and space debris. Exposure to high-energy solar particles, micrometeoroids, and atmospheric particles degrades surface materials through oxidation, erosion, and paint peeling, producing wavelength-dependent changes detectable with observations in Johnson-Cousins photometric bands.
These...
Gene expression is inherently stochastic, resulting in cell-to-cell variability in protein levels, even among genetically identical cells.
Such variability plays a crucial role in such processes as cell differentiation, stress response, and antibiotic tolerance.
- Proteins are synthesized in instantaneous discrete events, bursts, each producing a random number of...
Abstract
Car exhaust treatment is essential for mitigating harmful environmental and health effects caused by emissions from car engines. A usual approach for car exhaust emission control is the use of honeycomb monoliths integrated with advanced catalytic materials. Catalytic systems are widely used in diesel and car exhaust treatment due to their large surface area and effectiveness in...
The classification of smooth structures on a manifold $X$ is a classical problem in topology. Surgery theory provides a framework for solving this problem by calculating the structure set of $X$. One of the steps in this process involves finding normal invariants, which can be represented by a homotopy class of maps from $X$ to the space $\text{G}/\text{O}$. A similar notion exists in the...
Transient spark (TS) produces high concentrations of reactive oxygen and nitrogen species (RONS). Solvation of these gaseous molecules in water promotes various environmental applications. The solvation can be enhanced by an electrospray (ES), directly in TS discharge zone. In this work, we focus on the precursors of RONS, investigating the time resolved optical emission spectra of TS w/wo...
A Halin graph is a planar graph consisting of a tree and an additional cycle connecting all the leaves in such manner that no two edges are crossing.
Total colouring of a graph is a mapping from the set of vertices and edges to a set of colours such that no two neighbouring objects receive the same colour.
As there were only 4 known cubic Halin graphs with total chromatic index greater...
V práci sme sa snažili priblížiť žiakom druhého stupňa základnej školy koncepty teórie grafov pomocou zábavnej formy, únikovej hry. Hra bola určená pre žiakov siedmeho a ôsmeho ročníka základných škôl a realizovaná vo forme pracovného listu, ktorý žiaci riešili bez použitia počítača. Obsahovala sedem úloh, pričom jedna z nich bola bonusová.
Úlohy boli inšpirované úlohami zo súťaže iBobor a...
Absorption spectroscopy utilising an optical cavity represents a technique frequently employed for the purpose of investigating particle concentration, particularly in the context of analysing gases and atmospheric conditions. However, its use for investigating phase interfaces, particularly in the context of plasma discharges, is less well studied. The utilisation of incoherent broadband...
This project is concerned with the problem of classifying different smooth structures admitted by a smooth manifold up to homotopy. This classification is made possible by the tools of surgery theory and is summarized in the notion of the smooth structure set $\mathcal{S}^{DIFF}(X)$ of a smooth manifold $X$. We focus on cases when $X$ is the product of the complex projective space with a...
Jedna z mnohých výziev, ktorým čelí slovenské vysoké školstvo, je odliv študentov do zahraničia a dlhodobo klesajúci záujem o prírodovedné a technické študijné programy. Zo študentov, ktorí nastúpili na štúdium fyzikálnych odborov na FMFI UK medzi rokmi 2020 až 2024, ktorí mohli získať bakalársky titul z fyziky do 30. júna 2025, bolo úspešných 33 % študentov v konverznom programe a 41 %...
We continue the research of the notion of usefulness of information.
We formalize a problem by a regular language $L$ and we measure its complexity using the state complexity of the minimal automaton $A$ accepting the language $L$.
A language $L_{adv}$ provides a useful supplementary information about the problem, if it allows us to solve the problem easier, i.e., if it allows us to find an...
Transient spark (TS) a pulsed, atmospheric-pressure discharge transitioning between non-equilibrium and equilibrium plasma is important for applications like sterilization. This work focuses on optical diagnostics of the TS is high-speed gas-dynamic behavior. We employed high-speed schlieren imaging to visualize gas density gradients, complemented by numerical simulations of the electric...
Táto práca sa zameriava na využitie programu Algodoo vo vyučovaní fyziky. Algodoo poskytuje učiteľom fyziky možnosť doplniť experimenty realizované na hodinách fyziky počítačovým modelom alebo, v prípade potreby, niektoré experimenty úplne nahradiť, najmä v oblastiach mechaniky a optiky. Súčasťou práce je vytvorenie konkrétnych modelov a aktivít pre žiakov, ktoré podporujú rozvoj ich zručností...
Cieľom prezentovaného dizertačného projektu je identifikovať úlohy zo súťaže iBobor, ktoré nesú vysokú mieru informácie o algebrickom myslení (AM) a posúdiť ich z hľadiska charakteristiky. Výskum nadväzuje na aktuálne teoretické rámce AM a využíva prístup teórie odpovede na položku (IRT) na modelovanie pravdepodobnosti úspechu žiaka v teste AM na základe jeho výkonu v úlohách zo súťaže iBobor....
White matter hyperintensities (WMHs) or lesion in brain MRI are key biomarkers for neurological conditions, but detecting small lesions remains challenging. Existing deep learning models often act as “black boxes,” limiting clinical trust due to lack of interpretability. This study proposes a hybrid Xception-Vision Transformer (XViT) integrated with explainable AI (XAI) methods to enhance...
This work presents the fabrication and characterization of carbon microstructures from SU-8 photoresist by rapid thermal pyrolysis. The aim was to optimize lithography
and pyrolysis parameters to obtain conductive microstructures for sensor use. Structures were prepared on Si/SiO₂ and Al₂O₃ substrates and pyrolyzed up to 1200 °C
in nitrogen. The effect of temperature and dwell time on...
Polymeric materials are widely used across industries due to their low weight, high mechanical strength, chemical resistance, and cost-effectiveness. Despite these advantages, most polymers exhibit low surface energy and hydrophobicity, which limit their performance in applications such as coating, adhesion, painting, and composite interfaces [1]. Consequently, surface modification has become...
V práci sa zaoberáme analýzou diela významných osobností fyziky. Vybrané osobnosti sa okrem známych prínosov vo fyzike venovali aj filozofickým otázkam v oblastiach poznania, učenia sa a využitia získaných vedomostí. Táto práca je východiskom pre analýzu súčasného stavu, akým pristupujú pedagógovia na gymnáziách k fyzikálnemu vzdelávaniu, a filozoficko-psychologickým kontextom, ktoré možno...
The state-of-the-art complete algorithms to solve ABox abduction in DL include the original Reiter’s algorithm for minimal hitting sets alongside its more recent updates: Wotawa’s HST and Pill and Quaritch’s RC-Tree. On the other hand, incomplete methods that quickly find some but not all solutions include Junker’s QuickXplain and MergeXplain by Shchekotykhin et al. We present CATS, a new...
Abstract
Because of their unique components, particularly reactive oxygen and nitrogen species (RONS), non-thermal plasma and plasma-activated water (PAW) are used in a wide range of applications. PAW is mostly used in food safety [1] and biomedical applications [2], agriculture, and surface treatment and alterations [3]. Even though a lot of study has been done on the use of PAW [4],...
Plasmids are small, circular, extrachromosomal DNA molecules commonly found in bacteria. They can be transferred between different bacterial cells through horizontal gene transfer and often carry genes conferring antimicrobial resistance (AMR), making them a critical focus in the study of antibiotic resistance.
The goal of our work is to develop new bioinformatics methods for plasmid...
Chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate) is one of the harmful pesticide that persist long time in the environment and effect human health [1]. As a result of its accumulation in the environment and the effect it causes on human health its degradation into non-harmful substances is of high importance. In recent days, Plasma assisted degradation that involves...
Reliable quantification of the biogenic carbon content in liquid fuels is needed to satisfy EU renewable-fuel requirements (Directive (EU) 2018/2001). Accelerator-mass spectrometry (AMS) provides a fast, self-consistent, and well-validated approach to distinguishing fossil from biogenic carbon, fully in accordance with ASTM D6866-2024 Rev A and EN 16640 standards.
In this study, we employ a...
We propose X-MalNet, an inherently explainable malware detection framework based on Matrix Product States (MPS) tensor networks. Unlike previous explainability methods that provide fragmented insights, X-MalNet natively generates multi-level explanations from a single coherent architecture. The MPS explicitly learns the joint probability distribution of features and labels, enabling faithful...
Určenie veku artefaktov s presnosťou na niekoľko desaťročí v závislosti od veku vzorky, je dnes možné vďaka rádiouhlíkovému datovaniu a použitiu vysokocitlivej urýchľovačovej hmotnostnej spektrometrie. Datovanie pomocou rádiouhlíka využíva koncentráciu 14C na určenie veku vzorky a patrí medzi deštruktívne analytické metódy. Táto metóda v minulosti pomohla s odhaľovaním falzifikátov a ochranou...
The preservation of historical documents is a crucial component of cultural heritage protection. One significant threat to these artifacts is the appearance of colored stains, which may originate from biological agents (e.g., fungi, bacteria, insects) or synthetic compounds (e.g., ink stamps, dyes). Currently, conservators rely primarily on subjective visual assessment and invasive analysis to...
Emission spectroscopy is particularly valuable in space exploration, as it enables remote analysis of planetary atmospheres, cometary comas, and nebulas irradiated mainly by nearby stars. In comets, atomic sulphur can be stored inside the dust grains or as part of volatiles in the form of OCS, H$_2$S, SO, S$_2$ or CS$_2$ [1, 2]. The comet’s sulphur inventory is closely linked to the pre-solar...
A computer transmits visual information to a monitor as a continuous stream of RGB pixels, with their intensities encoded as voltage levels in the signal traveling through the video cable. The high-frequency voltage transitions of the signals generate unintentional electromagnetic emissions, which can be intercepted and used to reconstruct the displayed image. Under standard conditions, using...
In the age of AI becoming an everyday partner and support tool in both professional and private domains, users and stakeholders are increasingly confronted with the question of interpretability. This work contributes to the search for answers by exploring hidden meanings in the internal layers of convolutional neural networks trained on image classification tasks. Combining supervised...
CF-LIBS is a proven effective method for elemental analysis of metal alloys. EUROFER97’s development began more than 25 years ago as a replacement for radiologically undesired elements like Mo, Nb, Ni and Co with their lower-activation counterparts like Ta, W, Mn, and V. The addition of about 0.2 wt% of V improves creep strength and impact behavior, whereas about 1 wt% of W can acts as...
Laser-induced breakdown spectroscopy is a well-known analytical technique with a huge potential for characterization of materials in all three states of matter. It enables quick remote analysis without time-consuming sample preparation. The temporal evolution of plasma in liquid samples due to the nature of liquid itself provides further challenges. Plasma produced by a laser pulse (PPL) in...
We present a work-in-progress study on mitochondrial fluorescence microscopy scans using classical image-processing techniques. The workflow combines morphological and intensity-based segmentation with the extraction of descriptive textural features that capture structural variability of mitochondria. To identify the most informative characteristics, we apply systematic feature selection and...
Coumarin, a fluorescent aromatic compound widely used in dyes, pharmaceuticals, and optical brighteners, is frequently detected in industrial effluents and poses ecological risks due to its persistence, phototoxicity, and potential bioaccumulation in aquatic environments [1]. This study presents a novel approach for the rapid degradation of coumarin using recycled gas from a dielectric barrier...
Indoor air quality is a critical factor in occupant health,safety and building performance, making it a key concern in civil engineering and sustainable construction. Volatile organic compounds (VOCs), particularly ketones such as 2-hexanone, 3-hexanone, 2-heptanone, and 3-heptanone, are commonly emitted from building materials and finishing products.
This study applies Ion Mobility...
Future climate projections are based on future climate simulations by numerical climate models. Model performance is evaluated by comparing historical model simulations against observations. As model simulations are gridded, gridded observation-based datasets are widely used as the evaluation reference. These datasets can be created either by interpolation of station observations, or by using...
This study investigates electron collisions (10 – 100 eV) with molecular species using emission spectroscopy processes that are fundamental to the chemistry of extraterrestrial environments. Electron-induced chemistry, in which low-energy electrons interact with molecules, plays a crucial role in the study of objects in space and has significant implications for astrochemical research. At the...
We present selected results from the work in the topology group at KAG FMFI UK supported by the grant VEGA 1/0425/25. The main focus is on the results of the PhD student Ajay Raj, who defended his thesis in August 2025. His work is located in surgery theory which is a specific way of approaching classification problems of topological and smooth manifolds. His aim was to calculate the...
We present a bottom-up approach to an effective theory that simultaneously explains the matter–antimatter asymmetry via leptogenesis, the dark matter relic abundance via freeze-in or freeze-out mechanisms, and neutrino masses via the Weinberg operator. We show that, in the minimal scenario, only two new particles and a single portal operator coupling the visible and dark sectors are sufficient...
In this paper, we present innovative approaches to teaching probability that were developed as part of the KEGA 037UK-4/2024 project Innovative learning technologies in the preparation of future mathematics teachers and the project Digital Transformation of Education and Schools (DiTEdu, code ITMS2014+: 401402DVR6). These approaches aim to foster a deep conceptual understanding of...
Binary quantization approaches, which replace weight matrices with binary matrices and substitute costly multiplications with cheaper additions, offer a computationally efficient approach to address the increasing computational and storage requirements of Large Language Models (LLMs). However, the severe quantization constraint ($\pm1$) can lead to significant accuracy degradation.
In this...
Advances in experimental biology increasingly provide time-resolved data that capture essential aspects of complex biological dynamics. Yet, uncovering how the underlying components interact remains a challenging inverse problem, requiring the separation of systematic behavior from stochastic fluctuations and measurement noise.
Among existing approaches, the method of Brückner et al. (2020)...
Metamodelling in ontologies enables the structured representation of complex domains by defining relationships between concepts across multiple levels of abstraction. Subsumption, a core relation in hierarchical reasoning, provides a strong foundation for organizing ontological knowledge. In this work, we build on an extended form of higher-order description logic, denoted $\mathscr{H}...
In our contribution, we present the introduction of Challenge-based Education (CBE) in lower-secondary mathematics and sciences as a means to enhance pupils’ scientific competences and engagement. We described the design and implementation of activities that apply CBE principles to connect curricular content with real-world challenges. This approach supports the development of collaboration,...
Titanium dioxide nanotubes are promising nanomaterials with wide-range potential applications in energy, environmental, and medical fields, driven by their tunable structure and exceptional properties. However, pure TiO2 nanotubes usage is limited by relatively wide energy gap.
The fabrication and oxidation processes of iron-doped titanium nanotubes were investigated. The structural and...
A system of two doubly nonlinear diffusion equations acting on two different rectangles in $\mathbb{R}^2$, connected by nonlinear boundary conditions on the contact line, is studied. The goal is to present numerical simulations of this coupled problem. We use a conservative finite-volume discretization in space and fully implicit time stepping with adaptive step sizes and adaptive damping. The...
V našej prezentácii uvedieme prehľad programovacích nástrojov a edukačných materiálov na výučbu programovania pre nevidiacich žiakov rôznych vekových kategórií od prvého ročníka základnej školy až po maturantov.
Pre žiakov prvého stupňa ZŠ sú to robotické hračky Bee-Bot alebo Blue-Bot v kombinácii s tabuľkou Tactile Reader. Ďalej sa zmienime o fyzickom programovacom jazyku Code Jumper.
Pre...
Indoor air can be polluted by many different harmful contaminants, such as chemicals, viruses or bacteria, aerosols or fine particles from combustion, among others [1]. The recent global pandemic is the perfect example showing how contaminants such as viruses are dealt with. Instead of destroying or inactivating them, physical barriers, i.e. filters, were mostly used. Similarly, current...
Attack Trees (ATs) are a widely adopted formalism for modeling security threats. However, their conventional use relies on an unrealistic assumption of perfect knowledge, where the system's entire state and all adversarial actions are fully known. Real-world security interactions are characterized by limited visibility and finite resource constraints for both the attacker and the...
The study of three-dimensional objects in school mathematics is frequently mediated through planar projections. For many students, however, these two-dimensional representations do not sufficiently support the development of accurate spatial imagery, making it difficult to mentally reconstruct the intended 3D structure. Recent advances in low-cost 3D printing technologies provide new...
Our study explores how preservice teachers perceive the process of creating mind maps manually compared to generating them with artificial intelligence (AI). Over two academic years, 34 preservice teachers enrolled in the course Software for the Modern Teacher were tasked with creating mind maps on the theme of software and education. Initially, they constructed their mind maps using Coggle,...
In most eukaryotes, chromosomal DNA terminates with tandem repeats of a short G-rich motif, such as the canonical TTAGGG sequence. Here we report that nuclear chromosomes of several basidiomycetous yeasts classified into the order Microstromatales carry unusual telomeres. We demonstrate that instead of TTAGGG-like repeats these telomeres are composed of unique tandem arrays which are in most...
Coumarin is widely used in cosmetics and pharmaceuticals, has emerged as a persistent and potentially toxic contaminant. This study investigates coumarin degradation using a modified fountain dielectric barrier discharge (MF-DBD) plasma reactor, operated alone and in combination with WO₃, WO₃–ZnO, and ZnO catalysts. Under identical conditions (16 mg/L, atmospheric air pressure, 0–65 min),...
Malware analysis increasingly relies on machine learning classification. In this mission-critical domain, analysts require deeper insights that justify the classification results and help them understand how the results were reached. In the project EMA (NextGenerationEU/Recovery and Resilience Plan project No. 09I05-03-V02-00064), we focus on applications of eXplainable (XAI) methods that...
In this paper, we present innovative approaches to teaching probability that were developed as part of the KEGA 037UK-4/2024 project Innovative learning technologies in the preparation of future mathematics teachers and the project Digital Transformation of Education and Schools (DiTEdu, code ITMS2014+: 401402DVR6). These approaches aim to foster a deep conceptual understanding of...
The four-terminal measurement technique is a foundational and widely utilized method for determining the electrical conducting characteristics of materials, especially thin films, bulk crystals, semiconductors, and complex nanostructures. By employing four separate electrical contacts - two for current injection and two for voltage measurements - on top of a sample, this methodology...
We present selected results from the work in the topology group at KAG FMFI UK supported by the grant VEGA 1/0425/25. The main focus is on the results of the PhD student Ajay Raj, who defended his thesis in August 2025. His work is located in surgery theory which is a specific way of approaching classification problems of topological and smooth manifolds. His aim was to calculate the...
We introduce a stochastic model of cancer–immune coevolution, where mutations trigger effector responses. Simulations show that interactions impact outcomes (e.g. suppression), with implications for immunotherapy. We find signatures of selection in sequencing statistics such as the single-cell mutational burden distribution. (based on the paper: https://doi.org/10.7554/eLife.103970.3)
Pangenomes are becoming increasingly popular data structures for genomics analyses due to their ability to compactly represent the genetic diversity within populations. Constructing a pangenome graph, however, is still a time-consuming and expensive process. A promising approach for pangenome construction consists in progressively augmenting a pangenome graph with additional high-quality...
Súťaž Informatický bobor vznikla v roku 2004 v Litve. Jej myšlienka sa odvtedy rozšírila do ďalších európskych aj mimoeurópskych krajín. Jej hlavným cieľom je podporiť záujem žiakov, učiteľov a rodičov o informatiku a rozvoj digitálnych zručností u všetkých žiakov. Súťaž chce posilniť v mladých ľuďoch záujem o intenzívne a inovatívne používanie moderných digitálnych technológií pri učení...
We present a bottom-up approach to an effective theory that simultaneously explains the matter–antimatter asymmetry via leptogenesis, the dark matter relic abundance via freeze-in or freeze-out mechanisms, and neutrino masses via the Weinberg operator. We show that, in the minimal scenario, only two new particles and a single portal operator coupling the visible and dark sectors are sufficient...
In our presentation, we focus on the ongoing curriculum reform, the results of analyses of current trends in education in the field of school informatics, aspects of the process of creating a national document, such as the relationship between digital literacy and informatics or the role of artificial intelligence in education. The new legislation brings several changes, not only in the...
OSCAR (One-Station methods for site ChARacterisation) is an international, collaborative benchmark that compares single-station approaches—i.e., methods using a single three-component seismometer—for estimating subsurface structure. Its goal is to provide the missing standardized framework for comparing these increasingly popular methods, which offer low cost and simple logistics at the...
This presentation provides a statistical analysis of personality data based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Across three independent studies, we examine the psychometric and statistical properties of the instruments used to evaluate personality psychopathology. The first study tests the reliability and validity of the Structured Interview of Personality...
ACM and IEEE Curricula for Computing science defines seven disciplines of computing. One of the disciplines is Software engineering which deals with development of complex software systems. Software engineering is the important discipline as, according to U.S. Bureau of Labor Statistics, 42% of ‘computer and Information technology jobs’ are software developers and testers. The issue, however,...
The growing demand for large, diverse datasets in AI and machine learning is often limited by the cost, privacy, and complexity of real-world data collection. Synthetic Data Generation offers a powerful alternative-creating realistic, controllable datasets through computer graphics, generative models, and physics-based simulations.
This approach enables precise control over environments,...
The Creative Science project, developed with the Slovak Academy of Sciences, promotes experiential learning in physics and technical education. Using custom-made experiment kits and a methodological guide, the project aimed to boost pupils’ scientific and critical thinking and interest in science. A pilot study with 42 schools showed that pupils exposed to hands-on physics lessons achieved...
We introduce a birth–death model of neutral tumour evolution uniting summary statistics via dynamical matrices. We derive and solve recurrence relations to find analytical expressions for expected mutational distributions. We compare to known results and simulated data, validating our predictions. (based on the paper: https://doi.org/10.1371/journal.pcbi.1013241)
The ISOLDE facility at CERN is one of the world’s leading centers for the investigation of exotic nuclei and their structure. Thanks to large production yields and element-selective laser ionisation, ISOLDE provides access to a broad range of radioactive isotopes far from stability. Various experimental techniques, for example, laser or decay spectroscopy, are used to probe properties of these...
In the past decade, several research teams have investigated the bio-psycho-social aspects of students and analyzed the basic principles of personality theory, taking into account genetic mapping. Recently developed medical brain imaging techniques, combined with investigations into the fundamental connections between learning theories that encompass psychological, social, and biological...
Circular colourings are a relaxation of proper graph colourings where we allow real numbers as colours. They serve as a model for scheduling problems in which we have arbitrary starting times instead of aligned slots. We provide an overview of computational methods we successfully used to determine circular chromatic index of small graphs and discuss recent results related to the Upper Gap...
We prove the existence and uniqueness of periodic solutions of a first order differential equation
$$x'(t)=f(x(t))+x(\lfloor t \rfloor)g(t-\lfloor t \rfloor),\quad t\geq 0$$
that contains a piecewise constant term. Such equations admit periodic solutions and hence they can be used for numerical modelling of temperature changes in a space surrounded by environment with different...
KM3NeT collaboration announced an observation of the most energetic cosmic neutrino with energy of 220 PeV on Wednesday, February 12, 2025, by means of a publication in Nature journal. This event, practically near-horizontal muon traversing three-dimensional network of optical modules (photosensors) of the telescope, was registered by the ARCA detector that is located offshore Sicily at a...
Jedným zo spôsobov, akým dokáže systém umelej inteligencie pomenovať predmet na obraze je spriahnutie extraktora príznakov z obrazu s extraktorom príznakov textu. V takomto spoločnom priestore obrazových a textových príznakov je potom pre príznaky obrazu hľadať akým príznakom textu sú podobné. Robí to takto napríklad model CLIP, pričom používa kosínusovú podobnosť medzi príznakovým vektorom...
Cold plasma discharges generate reactive oxygen and nitrogen species (RONS), which can be trapped in the liquid phase to form plasma-activated water (PAW), a chemically rich solution with applications in agriculture, biomedicine, and environmental treatment. When transient spark (TS) discharges are coupled with electrospray (ES) microdroplet generation, PAW production efficiency increases...
Iterated function systems (IFSs) with probabilities have been investigated in various settings. In the simplest case, they can be interpreted as Markov chains. In this context, it was proved that for every continuous probability distribution $\mu$ with support in $\mathbb{R}$, there exists an IFS for which $\mu$ is the unique stationary distribution of the associated Markov chain. Moreover,...
Stránka WILMA.sk vznikla na Oddelení didaktiky matematiky FMFI UK s cieľom ponúknuť učiteľom matematiky rôzne inšpirácie a materiály priamo na výučbu, no aj na mimoškolskú činnosť. Na základe spätnej väzby od učiteľov vieme, že v období pred prázdninami si nami pravidelne vytvárané a publikované materiály nachádzajú u učiteľov obľubu. Zohľadňujúc túto skutočnosť, bol v júni 2025 na stránke...
Tento konferenčný príspevok je venovaný predstaveniu a zhodnoteniu spolupráce dvoch matematických pracovísk na Fakulte matematiky, fyziky a informatiky Univerzity Komenského v Bratislave (FMFI UK) s praktickou sférou. Katedra matematickej analýzy a numerickej matematiky a Katedra aplikovanej matematiky a štatistiky sú v priamom kontakte s desiatkami spoločností, ktoré pôsobia v rôznych...
Interactive Escape Rooms for Climate Crisis Awareness and Civic Engagement in School Education. International Erasmus+ project with Greece, Italy, Portugal and Romania.
EcoMystery project aims to integrate innovative educational methodologies with pressing environmental challenges to enhance the school community’s awareness of the climate crisis and strengthen civic engagement. Utilising the...
Direct injection of electrons into synthetic bone mineral hydroxyapatite can change its surface potential in thin films prepared by spin coating, reduce bacterial adhesion at the surface of bulk ceramics and impact biological adhesion. To explore this further, we investigate direct electron injection, and trapping of charge in hydroxyapatite thin films produced by Pulsed Laser Deposition (PLD)...
In this paper, we propose a novel approach for recovering focal lengths from three-view homographies. By examining the consistency of normal vectors between two homographies, we derive new explicit constraints between the focal lengths and homographies using an elimination technique. We demonstrate that three-view homographies provide two additional constraints, enabling the recovery of one or...
Challenge-based Education (CBE) is an innovative educational approach that engages pupils in solving real-world problems through active learning, collaboration, and the integration of knowledge across different subject areas. In this paper, we present a set of activities designed to implement the CBE method, aimed at lower secondary school pupils. We also discuss the results of the pilot...
Artificial neural networks are currently at their prime, mainly due to the bloom of deep learning. Despite their inspiration from brain processes, learning in such systems, based on error backpropagation (BP), is only loosely inspired by the actual neural mechanisms. Learning in the brain is local and makes use of the bidirectional flow of information. Our Universal Bidirectional...
Topological phases emerge from the global properties of electronic band structures, stabilized by time-reversal or mirror symmetries. Their hallmark is the presence of gapless boundary states that are robust against perturbations and enable charge transport without backscattering. To realize a non-trivial conducting state, we adopted a stacking strategy by fabricating a superlattice composed...
Graph Neural Networks (GNNs) are increasingly applied to cybersecurity tasks such as malware detection, intrusion detection, and program analysis, as they can model structured program representations and capture relational dependencies beyond flat feature vectors. However, their black-box nature poses challenges in security-critical do- mains, where analysts and stakeholders require...
Transition metal borides (TMBy) represent a structurally rich group of materials with attractive physical properties, including high hardness and high melting points, making them promising candidates for applications in extreme conditions. Considerable attention has been paid to overstoichiometric TMB2+Δ films with hexagonal α-P6/mmm structure exhibiting super-hardness attributed to high...
The Student Scientific Conference is an annual showcase of scientific and professional works by students of bachelor’s, master’s and doctoral studies from all fields of mathematics, physics, computer science and didactics of these disciplines. All contributions are assessed by a scientific committee, the best of them are awarded as winners or laureates of the ŠVK, or nominated for...
Binary quantization approaches, which replace weight matrices with binary matrices and substitute costly multiplications with cheaper additions, offer a computationally efficient approach to address the increasing computational and storage requirements of Large Language Models (LLMs). However, the severe quantization constraint ($\pm1$) can lead to significant accuracy degradation.
In this...
We study spaces that don’t have to be continuous like ordinary space but can instead be built from matrices that replace the usual notion of points. These matrix spaces allow us to explore what happens when geometry itself becomes quantum. Our work includes well-known examples such as the fuzzy sphere and newer constructions like the fuzzy onion, where several fuzzy layers form a richer...
Sparse Matrix-Vector Multiplication (SpMV) is a fundamental operation in the inference of sparse Large Language Models (LLMs). Because existing SpMV methods perform poorly under the low and unstructured sparsity ($30–90\%$) commonly observed in pruned LLMs, unstructured pruning struggled to deliver real memory reduction or speedup. We propose MACKO-SpMV, a GPU-optimized format and kernel...
Current demands on computing technologies and storage units, such as speed, low power consumption, and high memory density, are leading to the development of new technologies. One promising area is superconducting cryoelectronics, including qubits, superconducting spintronics, or memory cells. Devices combining two antagonistic phenomena – superconductivity and ferromagnetism – show great...
Cold atmospheric plasma generates multiple reactive oxygen and nitrogen species (RONS), which dissolve in water to form plasma-activated water (PAW), resulting in its subsequent chemical modifications. Due to the presence of RONS, PAW shows considerable potential in agriculture, as these species act as signaling molecules in plant metabolic pathways and enhance nutrient availability. This...
Beryllium-10 ($^{10}$Be) is a long-lived radioactive cosmogenic isotope of beryllium (half-life = 1.387 Ma), primarily produced in the Earth’s atmosphere through spallation reactions induced by high-energy cosmic rays. Owing to its extended half-life and β⁻-decay mode, the quantification of $^{10}$Be at ultratrace levels in natural samples is most effectively achieved using accelerator mass...
Most objects in space are too distant to be studied in situ. Therefore, emission spectroscopy is one of the primary methods used. The generation of excited species responsible for this emission can be induced either by radiation from nearby stars or by collisions with other particles. In our Solar System, planets and small bodies are constantly exposed to photon irradiation from the Sun. These...
Thin-film systems exhibiting magnetoresistive effects have found broad practical application in various industries, including nanoelectronics, automotive engineering, and biotechnology. During the operation of devices that utilize magnetoresistive elements (e.g., non-volatile magnetic memory such as MRAM, or magnetic field sensors), the materials are subjected to elevated temperatures. The...
This work is devoted to development and characterization of inter-electrode separators for alkaline water electrolysis (WE) for hydrogen production. The purpose of the separator is to prevent mixing of the produced hydrogen and oxygen, therefore the separator must possess low permeability to these gases under WE conditions. Meanwhile, the separator must be highly conductive to OH- ions to...
The versatility and design adaptability of the Spatial Heterodyne Spectrometer (SHS) have proven to be beneficial in various disciplines, including analyses in atmospheric, astrophysical, elemental, and others [1]. A hybrid of interferometric and dispersive domains of the spectrometers is implemented in the single SHS spectrometer, providing high throughput and resolutions with design...
Silver-containing nanocomposite coatings were deposited using the High Target Utilization Sputtering technique (HiTUS) by simultaneous sputtering of Ag target and polymerization of hexamethyldisiloxane (HMDSO) vapours in the radiofrequency plasma. The presence of silver in the form of nanoclusters with dimensions below 10 nm embedded in an amorphous organosilicon plasma polymer was confirmed...
The term "superconducting diode effect" (SDE) was introduced in the context of advancing superconducting quantum electronics. However, the ac rectification was observed in the 1960s in dc SQUIDs caused by asymmetry in their current–voltage characteristics in magnetic fields. Later, similar behavior was identified in wide thin films due to asymmetry in the Bean–Livingston edge...
In our laboratory, we study the interaction of light with small molecules (such as ammonia or NOx radicals). These particles often play a key role in everyday physical and chemical processes on both terrestrial and cosmic scales. One example is the characterization of exoplanets based on the detection of such molecules in their atmospheres.
Effective analysis of absorption signals requires a...
Modern experimental techniques, such as Accelerator Mass Spectrometry (AMS), allow us to analyze environmental samples with high sensitivity and resolution. The concentration of cosmogenic nuclides in these samples is the result of the interplay between three processes: production, transport, and deposition. The knowledge of involved processes and their simulations allowed us to obtain...
This study investigates laser ablation of materials relevant for thermonuclear reactor walls under various laser irradiation conditions. Copper was selected as the target material due to its high thermal and electrical conductivity and relevance in fusion technology. The study is focused on laser ablation processes using a EKSPLA NT342C laser system operating at a wavelength of 532 nm with...
On Monday, October 9, 2023, 20:23 CEST, an earthquake with a local magnitude of 4.9 occurred in Eastern Slovakia with an epicenter near the village of Ďapalovce. The epicentral macroseismic intensity reached 8° EMS-98. It was the strongest earthquake on the territory of Slovakia in more than 100 years (since earthquake on the night of January 9-10, 1906 near the municipality Dobrá Voda,...
Traveling-Wave Parametric Amplifiers (TWPAs) are essential tools for ultra-sensitive measurements, particularly in quantum systems. Their performance, however, is often limited by challenges in impedance and phase matching. Conventional phase-matching techniques, such as periodic impedance modulation or the use of resonators and phase shifters, complicate circuit design and increase impedance...
Volatile organic compounds (VOCs) such as toluene are major air pollutants, contributing to photochemical smog and posing severe environmental and health risks. Conventional abatement methods often require high operating temperatures or show poor efficiency for intermittent emissions. In this study, non-thermal plasma (NTP) assisted VOC decomposition was investigated using a dielectric barrier...
Jednou z hlavných výziev súčasného vzdelávania je, ako zmysluplne zapojiť študentov do procesu učenia sa. Učitelia na všetkých úrovniach vzdelávania, vrátane vysokoškolského, sa často stretávajú s klesajúcou motiváciou, roztrieštenou pozornosťou a pasívnymi študijnými návykmi študentov. Súčasná mladá generácia vyrastala v prostredí presýtenom technológiami, s okamžitým prístupom k informáciám...
