bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating Collisional and Radiative Processes: Important Datasets for Molecular Dynamics
Authors: Srećković V.A. , Iacob F. , Vujčić V.
Published: December 2024

According to García & Fuss (2012) and Verkhovtsev et al. (2016), understanding complex processes induced by photons and particles is a significant challenge in today's world. These processes could, for example, result in energy conversion and storage or be critical to the creation of novel light sources (Mason et al. 2014). In recent decades, new experimental techniques and computational chemistry methods have emerged as important tools for studying molecular interactions and dynamics. Furthermore, one can note the present importance of investigating collisional and radiative processes, as well as the associated A&M data (VAMDC, RADAM) (see, for example, Dubernet et al. 2016). Today, the scientific community and industry require access to such molecular data (Marinković et al. 2017). The purpose of this work is to investigate collisional and radiative processes of small molecules and give data for characterization and chemistry of such systems. We will present, discuss, compare, and analyze cross sections and rate coefficients. The results, i.e. the created datasets/databases, can be used for important activities such as modeling, industry, synchrotron experiments, and so on (Giuliani et al. 2014; Milosavljevic et al. 2011). - FULL TEXT available in PDF.
Earth's Lower Ionosphere under energetic events: solar flares and gamma ray bursts as drivers for VLF signal perturbations
Authors: Kolarski A. , Nina A. , Srećković V.A. , Arnaut F. , Langović M.
Published: December 2024

Earth's lower ionospheric perturbations induced by different phenomena, such as energetic solar flare events of high class on one hand and gamma ray bursts on the other, were examined through a remote sensing approach by utilization of VLF radio signals (Very Low Frequency, 3-30 kHz) propagating globally within Earth-ionosphere waveguide. Solar X-ray radiation data were taken from Geostationary Operational Environmental Satellites (GOES) database, while data related to gamma ray bursts were taken from Swift satellite database. VLF data used in this research are from Belgrade database, obtained from receiver system located at the Institute of Physics in Belgrade, Serbia, cover period of several consecutive years during solar cycle 24. Based on VLF registrations from European transmitters, temporal evolution and general patterns in VLF signal perturbations related to these events were examined, with main results related to D-region plasma behavior under such energetic events presented here. - FULL TEXT available in PDF.
Photodissociation processes in non-symmetric systems
Authors: Tošić S. , Srećković V.A. , Vujčić V.
Published: December 2024

New findings in the fields of atmospheric science, astrochemistry etc. have been made possible by recent experimental and theoretical developments. One of the most crucial processes in planetary atmospheres and interstellar media is photodissociation. A brief overview of the fundamental physical processes including photodissociation and photoionization of molecules of astronomical interest as well as new astrophysically relevant molecular species have recently been added to the Leiden VUV cross section database (Hrodmarsson and Dishoeck, 2023). The importance of these data for analyzing observations and measurement results in a variety of fields is also growing (Vujcic et al., 2023). On the other hand, despite of involvement of both ionic and neutral alkali hydride species in a number of astrophysical and astrochemical processes (Sreckovic et al., 2021), only a small amount of theory and observation is known about their spectroscopy, especially when it comes to molecule ions. Here we present results of investigations of the mechanisms of photodissociation processes in non-symmetric systems/configurations involving ions, molecular ions, hydrogen, helium, and alkali atoms. Quantum mechanical analysis of the cross-sections and spectral rate coefficient data has been carried out. - FULL TEXT available in PDF.
Elastic electron scattering by xenon atom and data coverage within BEAMDB
Authors: Marinković B.P. , Ivanović S.Đ. , Uskoković N.A.
Published: December 2024

We investigated data on elastic electron scattering by xenon atom in the intermediate electron energy range (from 10 eV to 100 eV). Our preliminary survey have been contrasted to those data curated within BEAMDB - Belgrade Electron/Atom (Molecule) DataBase. BEAMDB1 is one of the VAMDC (Virtual Atomic and Molecular Data Centre) nodes specialized for data on electron interactions (elastic scattering, excitation, ionization, energy loss spectra, threshold spectra) with atomic species. Previous recent work on xenon atom involves Auger spectra (Jureta et al. 2023). We just want to mention some of the earlier work on electron scattering that includes excitations (Filipović et al. 1988), ionization (Stephan and Märk, 1984) and elastic scattering (Cho et al. 2006). - FULL TEXT available in PDF.
Fitting of the current signal of the Pulsed Towsend experiment with the gradient descent algorithm
Authors: Simonović I.B. , Bošnjaković D.V. , Dujko S.
Published: December 2024

The Pulsed Townsend experiment is used for determining the transport coefficients for a swarm of electrons in gases (see e.g., Casey 2021, De Urquijo 2007, Haefliger 2018). These transport coefficients include drift velocity, longitudinal diffusion and the effective ionization coefficient. In general, these transport coefficients are determined by fitting an analytical expression, in which the current signal is expressed in terms of these transport coefficients, to the actual current signal that is measured in the experiment by a nonlinear curve fitting procedure. In the literature, different analytical expressions for the current signal are used by different authors, and the employed nonlinear curve fitting procedures are not always publicly available. For this reason, a systematic study of the fitting of the current signal of the Pulsed Towsend experiment is long overdue, and this work makes first steps in that direction.In this contribution, we investigate the applicability of the gradient descent algorithm for the fitting of the current signal of the Pulsed Towsend experiment. The gradient descent algorithm is a method for unconstrained mathematical optimization, that is commonly used to train machine learning models including linear regression, logistic regression, neural networks, and support vector machines (see e.g. Bishop 2006). This algorithm minimizes the desired differentiable multivariate function by making repeated steps in the direction opposite to the gradient.In this contribution, we investigate two different analytical expressions for the current signal from the Pulsed Towsend experiment. We have defined two machine learning models that implement these expressions in the torch.nn.Module class from the PyTorch library. PyTorch is an open-source library for machine learning, data science, and artificial intelligence, that has been originally developed by Meta AI (see e.g. Ketkar 2021). The transport coefficients, that are determined from the cur ... - FULL TEXT available in PDF.
Spatio-temporal dynamics of a microsecond pulsed glow discharge
Authors: Krstić I.B. , Obradović B.M. , Kuraica M.M.
Published: December 2024

As a type of pulsed discharges, microsecond pulsed glow discharges (µs-PGD) brought an improvement of the analytical characteristics of the GD sources for several optical and mass spectrometric methods. Advantages of µs-PGD are increasing signal outputs and the temporal resolution of analytical species from concomitant species in the discharge plasma. Another benefit of µs-PGD is that even though instantaneous power is higher, the average power can be significantly lower than in millisecond PGD, resulting in reduced thermal stress of the analyzing sample. The higher instantaneous power of the µs-PGD is closely related to the so- called “pre-peak”, a spike in the electrical current and a spike of plasma radiation at the leading edge of the discharge pulse. The radiation pre-peak, together with an increased radiation in afterglow for some spectral lines (after-peak) are responsible for the improvement of the analytical characteristics of the PGD in optical emission spectrometry. Here we present results of measurement of spatio-temporal distributions of several atomic spectral lines of copper in a Grimm-type µs-PGD.To run discharge, a laboratory made pulsed voltage power supply were used, with capability to ensure up to 300 W per pulse. For a space resolved emission measurements we used optical system contained of quartz lens and 1m- Spectrometer equipped with ICCD camera. Following the suggestion (Alberts et al al, 2010) measurements have done by using the frequency of 5 kHz and the pulse width of 30 μs. 170 μs off-time allows to investigate near afterglow of the discharge.At the line intensity distribution, three characteristic phases (or the discharge regimes) can be resolved: the pre-peak (0 – 5 µs) caused by fast increase of the applied voltage; steady-state (5 – 30 µs) during it the voltage has a constant value, and the afterglow when the voltage is switched off, see Fig. 1. There are the two space regions, characteristic for the discharge: the CF which bor ... - FULL TEXT available in PDF.
Helium plasma jet as a probe for the laser irradiance measurements
Authors: Sretenović G.B. , Kovačević V.V. , Obradović B.M. , Kuraica M.M. , Ranitović P.
Published: December 2024

The knowledge of the effective value of the laser power density in the arbitrary position is usually of importance for any experimental work. It has been shown that the non-resonant laser irradiation induces line shift through the dynamical Stark effect of the excited atoms (Dubreuil et al. 1978). The effect is shown to be of order of 4·10-3 nm/(MW·cm-2) for particular helium atom transition 43S - 23P at 471.3 nm. The work included theoretical calculations based on the second order perturbation theory and the experimental confirmation utilized by continuous wave CO2 laser irradiation of low-pressure discharge in helium.In this work we present preliminary results of the measurements of the helium line shift caused by helium atmospheric pressure plasma jet irradiation by tunable energy (4 mJ maximum) femtosecond ytterbium doped fiber laser at 1030 nm (Pharos, Light Conversion). Atmospheric pressure plasma jets represent controllable plasma devices of simple construction that found broad applications in various fields, from material science to medicine. These devices emit spatially and temporally stabilized low electron density streamers through the helium gas stream that flows into the air (Lu et al. 2014). Thus, their construction enables generation of plasma in free space which candidates them as ideal plasma probes.Helium atmospheric plasma jet based on the asymmetric dialectic barrier discharge was powered by 2.5 kV sinusoidal voltage at 30 kHz. The laser operated at the same frequency and its average power could be changed in range 0-20 W. The laser and the plasma jet were synchronized by means of delay generator in a manner that the laser light and the streamer appear at the same time at the same place. 1-m focal length spectrometer equipped with iCCD recorded helium emission at the particular wavelength. The laser intensity was kept bellow breakdown value. The recorded line profile and the line shift dependence on the applied power are given in Figure 1( ... - FULL TEXT available in PDF.
Constraining the Deser-Woodard non-local gravity by Fundamental plane of elliptical galaxies
Authors: Borka Jovanović V. , Borka D. , Capozziello S. , Jovanović P.
Published: December 2024

Among extended theories of gravity, there are the non-local theories of gravity. In the case when the non-local terms of such a theory are canceled out, the limit of General Relativity is obtained. Non-locality in the present context applies to field theory, and non-local field theory extends classical field theory. Here, we take non- local gravity model given in Deser & Woodard 2007.On the other hand, the Fundamental plane (FP) is an empirical relation among three global parameters of elliptical galaxies expressed as a relationship between the central projected velocity dispersion, the effective radius, and the mean effective surface brightness within effective radius (for more details see e.g. Dressler et al. 1987, Borka Jovanović et al. 2016, Capozziello et al. 2020).In this contribution we use freely available observations of elliptical galaxies from Burstein et al. (1997) (their effective radii, effective luminosities and characteristic velocities) in order to study if Deser-Woodard non-local gravity can recover FP of elliptical galaxies. We also use these data to constrain parameters of this gravity model and demonstrate that FP can be successfully recovered without need for dark matter hypothesis. - FULL TEXT available in PDF.
Analysis of flood fatalities in the Republic of Serbia
Authors: Langović Milica
Published: December 2024

Abstract: The paper analyses the impact of floods on the loss of human lives in the Republic of Serbia in the period 1960-2023. In the purpose of the paper, a dataset based on EM-DAT data on the number of floods and deaths caused by floods were analyzed in this period. It was shown that floods have not only socio-economic but also demographic consequences. Likewise, it has been established that floods occurred more frequently in Serbia at the beginning of the 21st century than in previous periods. Based on the available data, the floods in 1981 and 2014 were identified as the ones with the highest number of fatalities. In order to reduce effects of future floods on human life, the paper emphasized the importance of adequate policies. - FULL TEXT available in PDF.
Annual PM2.5 and PM10 Variations on Belgrade’s Mostar Interchange – Traffic Impact
Authors: Jevremović Sreten , Langović Milica , Kolarski Aleksandra , Arnaut Filip
Published: December 2024

Abstract: Air pollution is becoming an increasingly pronounced problem globally, while Belgrade is often one of the most polluted cities in Europe. Some of the most common emitters and air pollutants are individual combustion plants, factory plants and traffic. In this paper, the variations of PM2.5 and PM10 particles were analyzed in the four-year period (from 2018 to 2021) in the area of Mostar interchange in Belgrade. The results showed that there is a statistically significant difference in the levels of PM2.5 and PM10 particles by year, which is why the influence of traffic on the increase in the level of harmful substances in the air was analyzed. The analysis showed that traffic has no influence on the change of PM2.5 and PM10 particles at the analyzed location. The obtained results indicate that traffic, in this particular case, is not a central source of pollution, but of course it can have an impact on reducing air quality. Accordingly, the impacts of other emitters, such as individual combustion plants and factory plants, on the territory of Belgrade should be analyzed and determined in more detail, which will be the subject of future research. - FULL TEXT available in PDF.
Space weather influence and multifaceted observations of natural hazards events inferred from sub-ionospheric VLF/LF electric fields and satellite magnetic measurements
Authors: Eichelberger Hans , Nina Aleksandra , Y. Boudjada Mohammed , Kolarski Aleksandra , B. Veselinović Nikola , Nico Giovanni , Francesco Biagi Pier , A. Srećković Vladimir
Published: December 2024

Abstract: Monitoring of the ionosphere enables the detection of changes that are related to numerous processes on Earth. However, space weather, primarily solar radiation, has a very significant influence on the atmospheric layers. Variations caused by these influences can be affected by some processes on Earth, which can be used to detect relevant terrestrial processes. On the other hand, the strong influence of solar radiation can mask changes due to processes on Earth. Therefore, it is important to examine the impact of space weather on the detection of changes in signals associated with natural hazards. Natural hazards events like earthquakes or volcanic eruptions could significantly excite lithosphere – atmosphere– ionosphere coupling (LAIC) up to high altitudes with different physical processes. However, the impacts of specific phenomena are complex and the details are still difficult to disentangle.This study considers selected earthquakes (USGS catalogue) with magnitude M ≥5.5 related to LAIC coupling processes based on the combining of ground-based sub-ionospheric VLF/LF electric field measurements from the INFREP network and complementary low earth orbit (LEO) satellite magnetic field measurements. Ground- based and space borne observations require temporal and spatial proximity to the events.We investigate electric field narrowband VLF/LF transmitter signals propagating in the ionospheric waveguide and detected by two INFREP receiving stations in Belgrade (Serbia) and Graz (Austria). It encloses areas along the radio paths from the lithosphere and up to the ionospheric D/E-layers. The analyses are carried out in the time- and frequency-domain and are restricted to European sites due to the INFREP network infrastructure. Complementary magnetic field measurements are obtained by ESA’s three satellite Swarm mission at~500 km altitude (ionospheric F-region). Case studies like the 29.12.2020 earthquake, M6.4, Petrinja, Croatia, and the 06.02.2023 Turkey-Syria ... - FULL TEXT available in PDF.
Electron-induced excitation and recombination of BeH+ ions and isotopomers
Authors: Pop Nicolina , Djuissi Emerance , Bofelli Jeoffrey , Zsolt Mezei Janos , Iacob Felix , Niyonzima Sebastien , Reiter Detlev , Chakrabarti Kalyan , F. Schneider Ioan
Published: December 2024

Abstract: Cross sections and Maxwell rate coefficients for reactive collisons between electrons and Beryllium monohydride cations and isotopologues are computing using the Multichannel Quantum Defect Theory (MQDT). The key challenge in the use of beryllium as main chamber material for experimental and commercial fusion devices is to understand, predict and controle the characteristics of the thermonuclear burning plasma. Due to its toxicity, few experimental data are currently available. In order to model anddiagnose the low-temperature edge plasmas, a complete database for electron-impact collision processes is required for molecular species containing beryllium and hydrogen. Significant fractions of the eroded beryllium will be transported towards the divertor and will form compounds with the fuel atoms, molecules and/or molecular ions. For the fusion plasma edge, extensive cross sections and rate coefficients have been produced for BeH+ (Niyonzima et al., 2017), BeD+ (Niyonzima et al., 2018) and BeT+ (Pop et. al., 2021) cations. The isotopic effects demonstrates the quasi-independence of the rate coefficients on the istopologue, if they are represented with respect to the vibrational energy of the target, at a given electron temperature.New computations on extended energy/temperature range, up to 12 eV/30000 K, are ongoing. - FULL TEXT available in PDF.
Molecular Electron Collisions in Exoplanet Atmospheres and the Interstellar Medium
Authors: Iacob Felix
Published: December 2024

Abstract: Recent changes in the climate have sparked interest in studying molecular-electron collisions in exoplanet atmospheres and, to a greater extent, in the interstellar medium. The competitive model of quantum mechanics can be used to describe Feshbach resonances, which are extremely excited bound states superposed with the continuum. Because they generate dissociation at low energy, these bound states are essential for explaining the dissociative recombination of the molecule that often occurs in this plasma environment. One effective theory that yields quantitative findings for identifying the interaction indicated by potential energy curves is the R-Matrix technique.The contribution of Feshbach resonances to the dissociation of molecules, as indicated by the dissociative rates, will be discussed in this presentation. The illustrations are based on NS molecule. - FULL TEXT available in PDF.
Recent advances in the kinetic and fluid modeling of Resistive Plate Chambers
Authors: Dujko Saša , B. Simonović Ilija , Bošnjaković Danko
Published: December 2024

Abstract: This work explores and describes new advances in fluid and kinetic modeling of resistive plate chambers (RPCs). RPCs are gaseous particle detectors often used for triggering and timing purposes in many high-energy physics experiments. At the Large Hadron Collider at CERN, all mega science experiments, ATLAS, CMS, ALICE, and LHCb, use RPCs in slightly different configurations, mainly for triggering muons and particle identification (Abbrescia et al. 2024). RPCs are also used for detecting charged particles in extensive air showers, which are cascades of secondary particles created when a high-energy cosmic ray interacts with the Earth's atmosphere (Abreu et al. 2018). RPC detectors are a vital component of the Iron Calorimeter detector at the India-based Neutrino Observatory (Kumar et al. 2017). They are used to detect muons produced by neutrino interactions with the iron plates in the Iron Calorimeter. RPCs can also be used for air quality monitoring by analyzing ionization caused by pollutants. They also found their way in novel medical imaging technology that combines RPC technology and Positron Emission Tomography (Fonte et al. 2023). In most of these experiments and applications, RPCs are operated with a gas mixture composed of C2H2F4, iso-C4H10, and SF6. Due to the very high global warming potentials of C2H2F4 and SF6, the search for a suitable replacement for C2H2F4 and SF6 is currently one of the major concerns in RPC technology. This work explores the possibility of using C3H2F4 andC3HF5 instead of C2H2F4, as well as CF3I, C5F10O, and C4F7N instead of SF6. Using a swarm method of deriving cross sections, we have developed complete and consistent cross-section sets for electron scattering in these gases. Cross sections are then used as input to solve the Boltzmann equation. The hierarchy of kinetic equations resulting from a spherical harmonic decomposition of the Boltzmann equation in the hydrodynamic regime is solved numerically by expandin ... - FULL TEXT available in PDF.
Application of Stark broadening in astrophysics and space sciences
Authors: D. Christova Magdalena
Published: December 2024

Abstract: We will present a part of our recent calculated results for Stark broadening parameters of spectral lines. Semiclassical perturbation theory in collisional approach of Sahal-Bréchot and developed further is used. Plasma conditions of interest cover a wide range of temperatures and particle densities, and they are applicable for the interpretation and analysis of stellar spectra. A demonstration of Stark broadening influence on the spectral lines in stellar spectra will be given. - FULL TEXT available in PDF.
Fluence of energetic protons at L1 in heliosphere before and during some extreme space weather events in heliosphere
Authors: B. Veselinović Nikola , Savić Mihailo , Maričić Darije , Šterc Filip , R. Joković Dejan , M. Banjanac Radomir , L. Dragić Aleksandar
Published: December 2024

Abstract: The study of transient phenomena caused by solar activity is of great importance (Savić et al. 2023), as these events can affect Earth's magnetosphere, environment, technological infrastructure, and systems (see Kataoka et al. 2018, Belov et al. 2022, Kolarski et al. 2023, and references therein). Extreme events originating from the Sun, in addition to inducing various processes in the heliosphere such as shock waves and particle acceleration (Waterfall et al. 2023), can increase the flux of charged particles within the heliosphere.In this work, the relationship between various solar activity indices and event-integrated fluence spectra of energetic protons measured at Lagrange Point L1 has been studied. The investigation focuses on the parametrization of differential fluence spectra using several proposed models to characterize the fluence spectra before and during extreme events. Three functions used to model the energetic proton fluence spectra appear to be comparatively useful in this type of analysis. This study demonstrates that SEP enhancement at L1 concurrent with the arrival of the CME shock is well-modeled by modified power-law functions. However, structures that do not coincide with the shock arrival (and often precede it) are poorly modeled, leading to the conclusion that these particles are apparently not related to the shock and possibly have a different origin. - FULL TEXT available in PDF.
Aerosol vertical profiles and ABL heights derived from lidar measurements in Belgrade
Authors: Kuzmanoski Maja , Mijić Zoran
Published: December 2024

Abstract: Information on vertical profile of atmospheric aerosols is important in studies of aerosol contribution to air pollution, their role in cloud formation and radiative effects. Aerosol lidar measurements provide information on vertical profiles of aerosol backscatter and extinction coefficients. Besides, it can be used to derive the height of atmospheric boundary layer (ABL), which determines the volume available for dispersion of air pollution. Aerosol lidar measurements at 355 nm performed in Belgrade (Mijić et al., 2023) are used to derive vertical profile of aerosol backscatter coefficient and temporal changes of ABL height (Ilić et al. 2018). These measurements are used to determine the altitude of long-range transported aerosols (such as Saharan dust) and to detect their intrusion into the ABL. Selected cases of lidar-derived aerosol backscatter coefficient profiles corresponding to episodes of elevated air pollution, as well as episodes of long-range aerosol transport and their intrusion into the ABL, will be presented. Air pollution measurements in Belgrade, obtained from the Serbian Environmental Protection Agency (SEPA) automatic monitoring stations are used to select times of high and low particulate air pollution and to analyze the contribution of long- range transported aerosol to PM10 concentrations at surface level. - FULL TEXT available in PDF.
Impacts of seismic activity on human mobility
Authors: Langović Milica , A. Srećković Vladimir , Kolarski Aleksandra , Arnaut Filip , Jevremović Sreten
Published: December 2024

Abstract: Earthquakes are natural disasters that have led to the displacement of large number of people in different parts of the world. These geophysical events, often destructive in scale, lead to short- or long-term displacement from vulnerable areas. The aim of this research is to analyse the impact of earthquakes on the intensity and dynamics of human mobility in the Balkan region. For this purpose, data on internal displacement under the influence of earthquakes in the Balkan countries in the period 2008-2023 were analysed and processed. The results show that the earthquake is a serious push factor for human mobility and has a major influence on the decision of the population in the Balkans to migrate. It was found that the largest number of internal displacements under the influence of earthquakes was recorded in Croatia and Albania. However, it is important to point out that the intensity of displacement is directly related to the magnitude of the earthquake and the resulting living conditions and environmental damage. In order to provide a detailed overview of the different aspects of this topic, this paper emphasises the need for more detailed research on this topic in the area mentioned. - FULL TEXT available in PDF.
Overview of Serbian involvement in COST framework – new open call and networking tools for young researchers and ITC participants
Authors: Mijić Zoran , P. Marinković Bratislav
Published: December 2024

Abstract: Serbia is COST (European Cooperation in Science and Technology) full member country and during the last decade there is an increasing interest of researchers and innovators from Serbia to actively participate in COST networking activities. In this paper the statistical overview of Serbian participants will be presented based on the available data for 2023. There is an increasing trend in country representation in active COST actions reaching 97% in 2023, and almost double leadership positions in actions comparing to 2018. Taking into the account activity, actions Management Committee (MC) members from Serbia have the leading role and mobilization of young researchers is among top five countries. Having in mind MC members are nominated by COST national coordinator following specific national procedure (Mijić and Marinković, 2024) these statistical indicators are useful to assess the quality of the current national rules and its possible improvements. New open call OC- 2025-1 have been lunched and introduced young researchers and ITC (Inclusive Target Country) conference grants (Mijić and Marinković, 2024a) which will be discussed together with additional networking opportunities. - FULL TEXT available in PDF.
Non-typical Spectral Line Shapes from Laboratory Plasma of Interest for Astrophysics
Authors: Cvetanović Nikola , M. Obradović Bratislav
Published: December 2024

Abstract: Spectral line shapes are a powerful diagnostic tool for investigating both laboratory and astrophysical plasma. Typical applications include determination of plasma parameters and the strength of the electric or magnetic field. However, in certain cases atypical line shapes occur that cannot be explained using standard models for the line-profile analysis e.g. Doppler or pressure line broadening. To perform the line analysis in such cases, new and advanced fitting procedures must be developed, often paired with imaging and backed up by wider theoretical framework to take in to account the specific processes at play. The physical mechanisms that cause such line-shape effects in laboratory plasma are often similar or analogous to those in astrophysical plasma. Therefore, the methods can be seen as a link between the laboratory plasma formed in controlled experiments and the investigation of astrophysical objects. - FULL TEXT available in PDF.
Quantum calculation of the optical properties of dense plasma
Authors: M. Sakan Nenad , Simić Zoran , A. Srećković Vladimir , Dechev Momchil
Published: December 2024

Abstract:A problem of describing a optical properties of dense plasma arises from the inconsistency of the application of the models for plasma of moderate or extreme densities onto high density plasma. Although it is not of extreme interest in laser confined fusion, the interest of plasma of moderate and high density is of high importance in Solar and stellar plasma, especially in photosphere region. From the reason of applicability, the steps for inclusion of complex ions are made. Since the moderate density plasma models are not capable to describe a strong collective phenomena in dense plasma, and since commonly used molecular dynamic coupled with Schrodinger solver is computing power hungry and in case of moderate density plasma they must use a much bigger ansamble of particles with enlarged calculation error. Here a retrospective of approach in fully quantum model is presented. The relatively simple model is capable of describing a emitter in dense plasma. Here the focus would be both on model potential as well as ideas for further development of used model. The further steps could bring a more accurate and widelyapplicable model that could help in research of both theoretical as well as experimental research of dense plasma. - FULL TEXT available in PDF.
Preliminary Analysis of Barometric and Temperature Effects in Cosmic Muon Datasets Simulated Using CORSIKA
Authors: R. Savić Mihailo , B. Veselinović Nikola , L. Dragić Aleksandar , M. Maletić Dimitrije , R. Joković Dejan , M. Banjanac Radomir , Knežević David , Travar Miloš , I. Udovičić Vladimir
Published: December 2024

Abstract: Muon detectors are among the most widely used ground- based cosmic ray detectors, alongside neutron monitors. Due to the fact they detect higher energy primary cosmic rays, they serve as a complement to neutron monitors for long-term monitoring of cosmic ray variations and the study of space weather phenomena. Furthermore, alongside the existing independent detector setups and established networks, new muon detector networks are currently being developed and implemented.Secondary cosmic ray muons are sensitive to changes in atmospheric conditions, particularly variations in atmospheric pressure and temperature. Careful study of these effects offers a twofold benefit: first, it allows better understanding of the fundamental processes affecting muon propagation through the atmosphere; second, it allows the correction of atmospheric effects, thus increasing the sensitivity of muon detectors to variations of primary cosmic rays.Empirical models based on principal component analysis and machine learning have the benefit of taking into account the maximum information about the meteorological parameters. However, these are based on the assumption that all variations in muon count rates can be solely attributed to the change ofatmospheric parameters, and therefore introduce an inherent risk of overcorrection.To minimize this potential drawback, models can be trained and tested on datasets that exclusively reflect variations in atmospheric parameters. One way to produce such data is by using theCORSIKA package, which can simulate extensive atmospheric showers while incorporating changing atmospheric conditions. Here, we present an analysis of preliminary data generated through this approach to establish how effectively CORSIKA simulates atmospheric effects on cosmic ray muons. - FULL TEXT available in PDF.
The confined molecular systems and astrophysical models
Authors: A. Srećković Vladimir , Vujčić Veljko , S. Dimitrijević Milan , Pop Nicolina , Iacob Felix , Bezuglov Nikolai , Majlinger Zlatko , D. Christova Magdalena
Published: December 2024

Abstract: The importance of computational chemistry techniques for examining the dynamics and interactions of molecules enclosed in larger structures has increased over the last few decades (Srećković et al. 2020, Albert et al. 2020). Despite their vast scale, molecular clouds play an important but little understood role in confined systems (Reis et al. 2022). There are currently a few hundred molecular species known to exist in interstellar space, ranging from diatomic to massive anions, cations, and neutrals (see, e.g. de Lara-Castells and Hauser 2020, Roesky & Mandel 2010). Interstellar radiation is scattered and absorbed into molecular clouds and molecules can resistphotodissociation and/or photoionization (Vujčić et al. 2023). Therefore, it is essential to investigate both radiative and collisional mechanisms. - FULL TEXT available in PDF.
Novel Research in Astronomy & Earth Observation
Authors: A. Srećković Vladimir , Mijić Zoran , Kolarski Aleksandra , Langović Milica , Arnaut Filip , Jevremović Sreten , Barović Jelena , Kounchev Ognyan , Simeonov Georgi
Published: December 2024

Abstract: With a high potential for direct application in Earth and other planetary research, the innovative approach of the past few decades has promoted cooperation and productive synergies among disciplines like space exploration, atmospheric and Earth observations, laboratory and field experiments, and numerical modeling. To model atmospheres with supercomputers and diagnose astrophysical and laboratory plasma using atomic and molecular datasets, theoretical methodologies and data computation methods must be developed and improved (see e.g. Srećković et al., 2024 and references therein). To address complex climate issues and their consequences, multi-instrumental and multi-disciplinary expertise is required. As data grows, automated tools and retrieval approaches are increasingly being used (e.g., Škoda and Adam 2020). We participated in this research with our contribution. - FULL TEXT available in PDF.
Low ionosphere modeling: new dataset
Authors: A. Srećković Vladimir
Published: December 2024

Abstract: Severe solar radiation and activity can lead to a number ofnatural disasters, disrupt space communications and electrical equipment on Earth, and produce sudden ionospheric disturbances (SIDs) (see Srećković et al. 2021; Šulićet al. 2016). This work focuses on the analysis of ionosphere plasmas and their properties, as well as the investigation of SIDs utilizing very low frequency (VLF) radio signals to forecast the impact of strong radiation o society (FutureMed), supported by COST. - FULL TEXT available in PDF.
Orbital precession of S-stars in Yukawa-like gravity: Case of bulk mass distribution
Authors: Borka Jovanović Vesna , Borka Duško , F. Zakharov Alexander , Jovanović Predrag
Published: December 2024

Abstract: In this study we use a Yukawa-like correction of the Newtonian gravitational potential, proposed by C. Will (see Ref. Jovanović et al. 2024a) in order to obtain new bounds on graviton mass from the observed orbits of S-stars around Sgr A*, but taking into account bulk mass distribution (Jovanović et al. 2021). Orbital precession of investigated stars is influenced by other stars, gas and dark matter and it is expected that the stars represent the dominant component of the extended galactic mass distribution near the Sgr A*. We adopted a double power-law density profile of the bulk distribution of mass around supermassive black hole (SMBH) in the central regions of our galaxy. We also assumed that the orbital precession of S-stars is close to the prediction of General Relativity (GRAVITY Collaboration in 2020 and 2022) for Schwarzschild precession, but with a possible small discrepancy from it. By comparison of the observed orbits of bright stars (Gillessen et al. 2017) in the Galactic center with their simulated orbits in Yukawa-like gravitational potential, we estimated the constraints on the parameters of this Yukawa-like theory of gravity. Assuming that λrepresents the graviton Compton wavelength, we also found the corresponding upper bound of graviton mass. We also evaluated the parameters of the Yukawa-like gravity model in the case of different values of bulk mass density distribution of extended matter. The obtained results were then compared with our previous estimates (Jovanović et al. 2023, Jovanović et al. 2024b), as well as with the estimates of other authors. Also, obtained results are in a good agreement with the corresponding LIGO results. We believe that proposed method is a useful tool to evaluate parameters of the gravitational potential at the Galactic Center.
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Classroom Management in Increasing Student Learning Interest
Authors: Yulianta Eka
Published: December 2024

Classroom management is an important component in determining the success of the education process and one of the factors in improving the quality of education in Indonesia. The importance of classroom management makes every educational institution make maximum efforts to meet classroom management standards to improve the quality of the learning process. This research uses a qualitative approach with descriptive analysis. The research subjects were the principal, head of the expertise program and homeroom teacher. The data collection techniques used are the interview method, observation method, and documentation method, which will later obtain primary and secondary data to be analyzed together to draw conclusions. Based on the results of the research that the author has done, it can be concluded that classroom management at SMK Islam Moyudan in supporting the learning process is quite good. However, some classroom management has not been realized, among others, in the process of planning, organizing, maintaining, and supervising classroom infrastructure. The obstacles experienced are the lack of human resources in the field of administration and infrastructure as well as incoming funds for the procurement facility process and the slow infrastructure
THE METHOD OF SEMA-ANALYSIS OF THE CONCEPTS OF “FRIEND-ENEMY” IN KYRGYZ FOLK PROVERBS
Authors:   K.Tynystanov Issyk-Kul State University, D. T. Chynybayeva , F. M. Zhumagulova ,   K.Tynystanov Issyk-Kul State University
Published: December 2024

This article examines the work of sema in the cognitive aspect and component analysis, revealing the individual semantic nature of the word. The initial unit of any word or concept is called Sema. The question arises, what is the difference or similarity between these two concepts. As a similarity, they both study the semantic nature of the word, whereas as a difference, Seme refers to the individual semantic nature of each word, and semantics refers to the general meaning of the word. To be more precise how many meanings, significant signs in the word has so much seme that they are placed in a connecting semantic field. Therefore, the question arises, what are the semantic meanings of the antonymic concepts of “friend-enemy” that we are analyzing. When we hear the word friend, concepts and meanings associated with it arise in a person's mind.
Thus, the analysis of words by sema in a proverb not only gives a deep understanding of the meaning of this word, but also allows us to extract a new meaning from words that go unnoticed.
This reflects the semantic proximity and difference of the antonymic concepts of “friend-enemy” in Kyrgyz folk proverbs.
THE GRAMMATICAL CORRELATION BETWEEN SEMANTICS AND PRAGMATICS
Authors:   K.Tynystanov Issyk-Kul State University, E. Zh. Sagymbaeva
Published: December 2024

This article explores the interplay between the cognitive, physical, and linguistic worlds of human experience, focusing on the triangle formed by IDEA, ITEM, and LABEL. These elements interact through mutually defining correlations: ideas are represented by labels, labels signify items, and items realize ideas. The concept of meaning arises from this interaction, which is shared within speech communities. Geoffrey Leech's seven types of meaning conceptual, connotative, stylistic, affective, reflected, collocative and thematic are discussed, particularly in relation to how meaning is constructed and understood in different contexts.
Further, the text examines different sources of meaning, including lexical, grammatical, phonological and sociocultural meanings, distinguishing between code-based meanings (sememes) and user-based meanings (pragmemes). The role of grammar in determining meaning through functional relations and sentence structure is also addressed.
Additionally, meaning relations among words are analyzed, following John Lyons' classification into descriptive, expressive, and social meanings. Synonymy, polysemy, homonymy, metaphor, and metonymy are explained, alongside semantic phenomena like ambiguity, antonymy, hyponymy, and valency. Pragmatics is discussed through concepts like performatives, presuppositions, and speech act theory, including locutions, illocutions, and perlocutions. The analysis highlights how meaning is shaped by these relations and contexts, integrating both semantics and pragmatics into the broader understanding of language and communication.
LEXICAL TRANSLATION ERRORS IN CHINESE LANGUAGE TEXTBOOKS FOR RUSSIAN-SPEAKING STUDENTS
Authors:   Shanghai International Studies University, A. Zh. Arzykulova , N. K. Kalykova ,   K.Tynystanov Issyk-Kul State University
Published: December 2024

This study investigates the frequency and nature of translation errors in widely used Chinese language textbooks designed for Russian-speaking learners. By analyzing the source texts and their corresponding translations, the paper identifies common error types, including inaccurate word choice, incomplete or misleading annotations, and inconsistencies between word-level translations and sentence-level meaning. To mitigate these issues, the study proposes several recommendations. These include enhancing the interpretation of original Chinese words, ensuring the completeness and accuracy of annotations, addressing discrepancies between word and sentence-level translations, and involving native Chinese speakers in the editorial process. By implementing these strategies, the quality of Chinese language textbooks can be significantly improved, fostering more effective language learning for Russian-speaking students.
Exploring the Effectiveness of Concept-Based Instruction Versus Deductive Methods in Teaching English Grammar
Authors: Wang Ponna , Ricard Buehler , Guang Zhou
Published: December 2024

Objective: This study investigates the impact of Concept-Based Instruction (CBI) compared to deductive methods on English grammar knowledge, student engagement and overall student teacher satisfaction in Sihanoukville, Cambodia.Methods: A quasi-experimental design was used with two groups of student teachers. In the CBI group, the experimental group was taught using CBI, while the control group used deductive methods. Grammar knowledge was assessed with pre- and post-tests, and student engagement and satisfaction were measured through observation and surveys. Statistical analyses were performed on the data to evaluate the effect of each teaching method.Results: The results showed that the CBI group significantly outperformed the control group in grammar knowledge, and they also reported significantly higher levels of engagement and satisfaction. Through CBI, students learned in an active, collaborative and meaningful way, thus improving learning outcomes.Novelty: By extending the evidence base for the effectiveness of CBI in language teaching in Cambodia, this study adds to the growing body of data supporting these claims, particularly in relation to the practice of CBI in teaching in Cambodian contexts. It also explores how a task and collaborative learning perspective can be applied to improve student outcomes in English language teaching.Theoretical and policy implications: The study confirms that CBI is effective in English language teaching and is consistent with the principles of constructivist learning theories. Based on the findings, they reflect on the implications for policy makers and educators and suggest that CBI could be integrated into language curricula to create more dynamic and effective learning environments.
Revolutionising education: In the midst of the COVID-19 crisis and its global implications, China pioneers online learning strategies
Authors: Lojunt Ming , Lie Shanshan lie , Li Fangmei Li
Published: December 2024

Objective: This study investigates the effectiveness and global implications of China's innovative online education strategies implemented during the COVID-19 pandemic, with a focus on academic performance, engagement, and equity in learning outcomes.Methods: A quasi-experimental design was employed, utilizing data from 700 undergraduate students in Wuhan, China, collected from 2019 to 2024. Statistical analyses, including paired t-tests and regression models, were conducted to evaluate differences in academic performance across demographic groups and assess the correlation between engagement levels and learning outcomes.Results: The findings revealed that China's large-scale online education initiatives significantly enhanced academic performance and engagement, especially among urban students. However, challenges such as the digital divide persisted, disproportionately affecting rural learners. These insights emphasize the importance of equitable resource distribution in online education.Novelty: This research provides a unique perspective on the rapid adaptation of educational systems during a global crisis, highlighting China's unprecedented efforts to maintain learning continuity. It identifies both strengths and limitations of large-scale online learning, offering innovative solutions for bridging gaps in digital education.Theory and Policy Implications: The results validate key theoretical frameworks, including the Technology Acceptance Model and Engagement Theory, while providing actionable recommendations for policymakers. These include strategies for enhancing digital infrastructure, improving accessibility, and fostering sustainable online education models globally