bluuebunny/crossref_metadata_2025 huggingface dataset:
Advancing Sustainability Through Green Public Procurement: A Comprehensive Analysis
Authors: Ahmari Dhafer Al , Brika Said K.
Published: December 2024

Greener Supply Initiatives acquisitions have received much focus from researchers, policymakers, and practitioners all over the world in the last four decades as a new approach for green public procurement. GPP practices and policies motivate the consideration of environmental criteria in the government buying processes. The present study attempts to put GPP into a historical perspective of research evolution by conducting a bibliometric analysis for public procurement, using 704 publications obtained from the Scopus database. Content and network analyses allow us to determine the existing thematic clusters, outstanding authors, and trends, as well as gaps in this developing area. The findings of this research suggest that the need to do research in this area has been gradually rising, and studying the effects of GPP on environmental management, principles of the circular economy, and sustainable development goals are among the major milestones made. It further explains the nature of the interaction that exists between the publish and perish brackets, that is, the academia, the industry, and the government. In order to provide a framework and context for GPP research, the authors also investigate which of the most cited papers references each other. The results open and outline a number of avenues for future research, such as the combination of digital information technologies and GPP processes and the inter-sectoral angles. This knowledge is beneficial both for scholars and practitioners, making it possible to propose more creative ways of fully exploiting the opportunities offered by green public procurement practices. This paper contributes to existing knowledge instead of being the last word on the subject and simultaneously offers possibilities for cross-disciplinary research on green public procurement and its importance in attaining the goals of sustainable public procurement.
DESIGNING AN ADVANCED MACHINE LEARNING-BASED PATIENT-CENTRIC DECISION SUPPORT MODEL FOR OPTIMIZED IVF TREATMENT RECOMMENDATION
Authors:   Sankalchand Patel University, Visnagar, Gujarat, India., Brahmbhatt Niku , Nakrani Tulsidas ,   Sankalchand Patel University, Visnagar, Gujarat, India.
Published: December 2024

In Vitro Fertilization (IVF) is a key assisted reproductive technique designed for individuals facing difficulties in natural conception. Due to IVF's complexity, personalized treatment recommendations are essential to maximize success rates while considering each patient's unique health profile. This study aims to create a machine learning-based, patient-centric Decision Support System (DSS) to optimize IVF treatment. By analyzing extensive patient data, including clinical and lifestyle factors, the study employs advanced algorithms such as Long Short-Term Memory (LSTM), Convolutional Neural Network (CNN), Light Gradient Boosting Machine (LightGBM), and Multi-Layer Perceptron (MLP), achieving notable prediction accuracies. Light GBM stands out with an accuracy of 84.97%, precision of 86.95%, and recall of 86.43%, demonstrating its reliability in IVF treatment recommendations. This proposed model not only advances decision-making in IVF treatments but also promotes a personalized, data-driven approach, offering clinicians accurate, consistent insights into each patient’s IVF needs, which can significantly improve treatment outcomes. Future work includes enhancing model robustness across diverse populations.
Autologous Transplantation of Dental Pulp Tissue - a Radiographic Evaluation
Authors: Hussein Dina Nashaat Hassan , El Sayed Hassanien Ehab , Abu Seida Ashraf , Abdel Aziz Tarek Mostafa
Published: December 2024

The study used decellularized autologous pulp tissue as a scaffold for regeneration of root canals of immature infected teeth. Four dogs’ premolar teeth were used. 96 roots of premolars were divided into four groups according to the treatment protocol. Group I: Dental pulp tissue transplantation and blood clot. Group II: Dental pulp tissue transplantation. Group III: Conventional regeneration. Group IV: Negative control group. Each subgroup was radiographically evaluated. Results revealed that after one as well as three months, there was no statistically significant difference between percentage increase in root lengths in the four groups, while in all groups, the percentage increase in root length after three months showed statistically significantly higher value than one month (P-value <0.001). Regarding dentin thickness, after one as well as three months, there was no statistically significant difference between percentage increase in dentin thickness in the four groups, while in all groups, the percentage increase in dentin thickness after three months showed statistically significantly higher value than one month (P-value <0.001). After one as well as three months, there was a statistically significant difference between percentages of apical closure in the four groups. Pair-wise comparisons between groups revealed that Group IV showed the statistically significantly highest percentage of apical closure. In all groups, the percentage of apical closure after three months showed statistically significantly higher value than one month (P-value <0.001). Decellularized pulp tissue can be successfully used as a scaffold in promoting pulp tissue regeneration.
Marketing digital y la personalización basada en inteligencia artificial
Authors: Pazmiño Arellano Stalin Gorky , Pazmiño Rodríguez Luis Danilo
Published: December 2024

El uso de la inteligencia artificial y sus implicaciones en la relación entre las marcas y el consumidor es igualmente un punto que marca la evolución. Por supuesto, la inteligencia artificial ha elevado la experiencia del consumidor, lo que solo puede ayudar a aumentar las estrategias de marketing. Tal alteración se realiza principalmente a través de la aplicación de numerosos algoritmos de esta inteligencia que logran superar las complejidades que se generan alrededor del patrón de comportamiento del consumidor. Hay una transición en el enfoque entre el trabajo y el consumidor, ya que la monitorización y optimización en tiempo real de la satisfacción del consumidor puede incluir elementos como análisis predictivos, codificación facial o métodos interactivos, predictivos y asistidos por animación. Este documento describe la personalización como un objetivo general en el comercio electrónico, con una descripción más detallada que incluye algunos cubos de comportamiento, emoción y cognición del consumidor. Tal comprensión amplia de la personalización también se basa en el análisis extenso de la literatura de arte económico cuyos trabajos son densos en el procesamiento moderno del lenguaje y algoritmos de aprendizaje automático para explicar cómo y por qué los consumidores actúan de la manera en que lo hacen. El gran reto que enfrentan, a su vez, se centra en la creación e implantación de estrategias de personalización que sean efectivas y que, además (y, quizás, lo que sería más importante), sean pertinentes en la pluralidad del entorno del marketing actual.
Proporsi Individu yang Memiliki Telepon Genggam 2021–2023 dalam Perspektif Teknologi Informasi dan Komunikasi (TIK)
Authors: Dwi Saputra Reynaldi , Dinda Marsyanadya Putri  , Jadiaman Parhusip
Published: December 2024

Penelitian ini menganalisis proporsi individu yang memiliki telepon genggam di Pulau Kalimantan dan Pulau Jawa selama periode 2021 hingga 2023. Telepon genggam, terutama smartphone, telah menjadi bagian integral dari kehidupan masyarakat, berfungsi sebagai alat komunikasi dan penunjang aktivitas sosial serta pendidikan. Tinjauan pustaka menunjukkan bahwa penggunaan telepon genggam di Indonesia, khususnya di kalangan mahasiswa, terus meningkat, dengan mahasiswa sebagai kelompok pengguna terbanyak, mencapai 85% dari total pengguna internet di Indonesia. Metode penelitian yang digunakan adalah pendekatan kuantitatif dengan memanfaatkan data sekunder dari sumber terpercaya, termasuk laporan dari Badan Pusat Statistik (BPS). Hasil penelitian menunjukkan bahwa pada tahun 2021, Kalimantan Timur memiliki persentase kepemilikan telepon genggam tertinggi sebesar 81,10%, yang meningkat menjadi 81,75% pada tahun 2023. Sementara itu, Kalimantan Selatan mencatat penurunan dari 70,51% pada tahun 2022 menjadi 68,98% pada tahun 2023. Di Pulau Jawa, DKI Jakarta mencatat peningkatan tertinggi sebesar 14,65% selama periode yang sama, dari 67,82% pada tahun 2021 menjadi 82,47% pada tahun 2023. Penelitian ini juga mencatat adanya kesenjangan digital dan ketimpangan dalam akses terhadap teknologi di berbagai wilayah. Dengan pendekatan kuantitatif dan data sekunder yang akurat, penelitian ini memberikan gambaran mengenai perkembangan kepemilikan telepon genggam dan relevansinya dalam mendukung transformasi di bidang Teknologi Informasi dan Komunikasi (TIK). Penelitian ini diharapkan dapat menjadi acuan untuk penelitian lebih lanjut.
The Intersection of Feminist Psychoanalysis and Literature: A Critical Examination of Sylvia Plath’s The Bell Jar and Charlotte Perkins Gilman’s "The Yellow Wallpaper"
Authors: Fatima Rameen
Published: December 2024

This paper explores Sylvia Plath's "The Bell Jar" and Charlotte Perkins Gilman's "The Yellow Wallpaper" through a feminist psychoanalytical lens, uncovering how Freudian theories have perpetuated gender biases. By examining the themes of hypocrisy and ontological insecurity, this analysis reveals the profound impact of societal expectations on women's mental well-being.  The relationship between the two works and feminine writing and the way they both undermine conventional narrative formations while presenting genuine voices of women is also explored in the analysis. Last, this paper also examines the ongoing significance of "The Bell Jar" and "The Yellow Wallpaper" in feminist and women's mental health contexts, emphasizing their continued relevance today.
The Moderating Effect Of Social Media Influencer On The Relationship Between Social Media Marketing And Consumer Engagement In Retail Fashion Industry In Bangladesh
Authors:   Putra Business School, Universiti Putra Malaysia, Serdang, Malaysia, Akash KH Parvez , Hamid Prof. Dr. Abu Bakar Abdul ,   Associate Fellow, Putra Business School, Universiti Putra Malaysia, Serdang, Malaysia
Published: December 2024

This study investigates the impact of social media marketing on consumer engagement, focusing on the moderating role of social media influencers within the Bangladeshi fashion retailers. By examining the relationships between various types of social media content—informativeness, electronic word of mouth (eWOM), entertaining content, and trendiness—and consumer engagement, the research posits that social media influencers can amplify or diminish these effects. Utilizing Partial Least Squares Structural Equation Modeling (PLS-SEM) to analyze data from a sample of 202 consumers, the study finds that all types of content significantly influence consumer engagement, with influencers enhancing the impact of entertaining and trendy content more than informative and eWOM content. The results align with previous research, confirming the robustness of these relationships and highlighting the need for alignment between influencer characteristics, brand values, and audience preferences. These findings have important implications for policymakers, academics, and industry practitioners. Industry practitioners should prioritize content quality and strategically select influencers to maximize engagement. Despite the study's limitations, including its focus on a specific market and cross-sectional data, it offers a robust framework for enhancing social media marketing effectiveness. Overall, the study underscores the strategic value of combining high-quality content with influencer marketing to drive consumer engagement, offering insights applicable to the Bangladeshi clothing retail industry and beyond.
SUPERNOVAE AS TRACERS OF THE STRUCTURE AND EVOLUTION OF THE SURROUNDING UNIVERSE
Authors: Kurfürst Petr
Published: December 2024

Abstract. The impact of mass lost from hot stars in general, including supernovae (SNe), as probably the leading contributor, has a direct impact on the evolution not only of stars but the entire universe. We study the interactions of expanding supernova (SN) envelopes with aspherical dense circumstellar medium (CSM) of various morphologies, including circum- stellar disks, bipolar lobes, or overdense layers of colliding ejected matter in binary systems. Many possible mechanisms can lead to wild eruptions of vast amounts of matter from po- tential SNe progenitors for a long time or shortly before the SN explosion. These effects are manifested by irregularities and bumps in light curves and asymmetries in spectra. Since massive stars usually end their lives as SNe, they appear to be candidates for neutron stars, black holes, gamma-ray bursts, or magnetars; understanding the behavior of the processes shortly before and after the SN explosions and their impact on the surroundings will help us understand how the stars become precursors to these exotic and interesting stellar objects.
MONITORING BLAZAR VARIABILITY TO UNDERSTAND EXTRAGALACTIC JETS
Authors: Maria Raiteri Claudia
Published: December 2024

Abstract. We review the main topics in the field of blazar multiwavelength variability as a tool to understand the physics and structure of extragalactic jets and their central engine. We address issues such as the cross-correlation between flux variations at different frequencies, the mechanisms to explain the long-term and short-term variability, the size of the jet emitting regions, the polarization behaviour, and the periodicities detected in the multiwavelength light curves.
WHY DO DIFFERENT EARLY-TYPE-GALAXIES HAVE DIFFERENT AMOUNTS OF ROTATIONAL SUPPORT?
Authors: Bílek Michal , Duc Pierre-Alain , Sola E.
Published: December 2024

Abstract. Early-type galaxies (ETGs, i.e. elliptical and lenticular galaxies) differ in their amount of rotational support – some are purely supported by velocity dispersion, while oth- ers show pronounced ordered rotation. Cosmological hydrodynamical simulations show that the progenitors of all ETGs were first rotating quickly, but then mergers decreased their rotational support. In the presented work, we studied this process using an observational archaeological approach. Namely, we inspected the correlations of 23 merger-sensitive char- acteristics of local ETGs with a parameter quantifying the rotational support. We used a volume-limited sample of local ETGs, that are not in galaxy clusters, from the MATLAS survey. We found, for example, that slowly rotating galaxies have tidal features and kinemat- ically distinct components more often and have lower metallicities. We sought for mutual interpretation of the correlations among all 23 quantities, together with literature results on high-redshift massive galaxies. There seems to be only one interpretation possible: on average, ETGs lose their rotational support through multiple minor wet mergers happening at the redshifts above about two.
PHASE-SPACE CORRELATIONS OF SATELLITE GALAXY SYSTEMS AND CHALLENGES TO ΛCDM COSMOLOGY
Authors: S. Pawlowski Marcel
Published: December 2024

Abstract. Driven by the increasingly complete observational knowledge of systems of satel- lite galaxies, mutual spatial alignments and relations in velocities among satellites belonging to a common host have become a productive field of research. The Planes of Satellite Galax- ies issue is maybe the best-known type of such phase-space correlations, with an ongoing, controversial debate on how much of a challenge it poses for the ΛCDM model of cosmol- ogy. With the fast expansion of proper motion measurements in recent years, largely driven by the Gaia mission, other peculiar phase-space correlations have been uncovered among the satellites of the Milky Way. At the same time, more complete observational samples of satellite galaxies around more distant hosts now enable us to expand the study of such cor- relations to the Andromeda galaxy and beyond. This contribution briefly reviews the highly active field of phase-space correlations among satellite galaxy systems, mainly summarizing recent results concerning observed satellite structures and what formation scenarios have been suggested for these peculiar arrangements.
SPECIFIC ANGULAR MOMENTUM CORRELATION WITH THE NUMBER OF SATELLITES
Authors: Lalović Ana , Jovanović Milena , Knežević Sladjana , Samurović Srdjan
Published: December 2024

Abstract. The number of satellites is correlated with the mass of the galaxy bulge and bulge-to-total ratio, indicating that the origin of satellites might be related to the mechanism responsible for bulge creation/growth. In this work, we have found that specific angular momentum correlates positively with the number of satellites for a sample of six nearby galaxies for which we have a complete census of the satellite population. Contrary to our previous work where we found a negative correlation using an approximate formula for specific angular momentum, in this work we have measured specific angular momentum more thoroughly: using both rotation curve data and galaxy mass distribution in the near infrared. Disagreement can be explained by the difference between approximate and more accurate measurements of angular momentum.
THE IMPORTANCE OF INTERACTION STRENGTH FOR NON-MERGER GALAXY ENCOUNTERS
Authors: Mitrašinović Ana
Published: December 2024

Abstract. Galaxy flybys, a class of non-merger interactions, outnumber mergers at lower redshifts (e.g. z ≤ 2), particularly in higher-density environments. Some of the previous research adopted merger-based classification based on the mass ratio of interacting galaxies, differentiating between equal-mass and lower-mass flybys (i.e. major versus minor). However, cosmological simulations showed that major flybys are extremely rare and almost exclusively distant, while minor ones are much more frequent, with the secondary galaxy penetrating deep into the primary. We demonstrated that this leads to comparable strengths of interaction between the two sub-classes and essentially the same effects. Focusing on morphological consequences, we will showcase a few examples (formation of spirals, bars, and some complex structures). Thus, flybys should be classified primarily based on the interaction strength and explored further as they contribute to the structural diversity of galaxies observed in the local Universe.
REDUCTION OF THE VLF SIGNAL NOISE AS POTENTIAL EARTHQUAKE PREKURSOR: PILOT STUDIES
Authors: Nina Aleksandra
Published: December 2024

Abstract. Studies of pre-earthquake disturbances in the ionosphere since the middle of the last century point to several types of potential precursors to these natural events. A large number of them are detected as disturbances in the Global navigation satellite system (GNSS) and very low / low frequency (VLF/LF) signals a few days before the earthquake. However, the analysis of the VLF signal emitted in Italy and received in Belgrade in the period around the earthquake in Kraljevo that occurred on 3 November, 2010 indicates a potentially new type of these precursors. It is visible as a reduction of the VLF signal noise which starts several minutes or several tens of minutes before earthquake. In addition, Fourier transform of the recorded data indicates wave excitations at discrete waveperiods under 1.5 s, and wave attenuations at other waveperiods. In this paper, pilot studies of the noise reduction of the amplitude and phase of the mentioned VLF signal in both time and frequency domains are presented. The data recorded by the Absolute Phase and Amplitude Logger (AbsPAL) receiver located at the Institute of Physics Belgrade on November 3, 4 and 9, 2010, and during the period of intense seismic activity when almost 1000 earthquakes occurred in Central Italy from October 25 to November 3, 2016, are analyzed. The obtained results indicate possible differences in the signal noise reduction in cases when the observed earthquake follow and not follow previous earthquakes in approximately the same area. Namely, in the first case, the signal noise reduction may already be present so that no new reductions occur before subsequent earthquakes. On the analyzed sample of 35 earthquakes of minimum magnitude 4, the signal noise is reduced in over 90% of cases. In the remaining three cases, it cannot be clearly concluded whether this reduction exists due to its reduced value over a longer time period, which can be explained by the intense seismic activity in that period.
ACCELERATING MCRT SIMULATIONS USING DIMENSIONALITY REDUCTION TECHNIQUES AND INLA
Authors: Smole Majda , Rino-Silvestre Joao , González-Gaitán Santiago , Stalevski Marko
Published: December 2024

Abstract. We propose a post-processing technique for Monte Carlo radiative transfer (MCRT) simulations with a main goal to reduce the total computational run time required for high quality images, by enhancing the output of lower quality images. Our method combines dimensionality reduction techniques with integrated nested Laplace approximation (INLA) to detect and reconstruct the underlying structure in lower quality images or images with missing data. We test the efficiency of our approach using high resolution synthetic observations of Milky Way-sized galaxy from the SKIRT Auriga project. This technique is able to reproduce high-photon-number reference images ∼ 5 times faster with median residuals below ∼ 20%.
PROPERTIES OF THE TIDAL SUBSTRUCTURES IN THE ANDROMEDA GALAXY
Authors: Milošević Stanislav
Published: December 2024

Abstract. We investigate the properties of the Giant Stellar Stream (GSS), formed in the merger of Andromeda galaxy (M31) and dwarf galaxy, the satellite of M31. We used N-body simulations to explain the properties of tidal substructures. The orientation of the GSS, distances, and velocities from our simulation are in agreement with the observed one. We confirmed that the Northeast shelf (NE) and West shelf (W) were formed in the same merger event. For the first time, we explained the observed metallicity distribution in the GSS and shell system. With a linearly decreasing gradient of the initial metallicity in the dwarf galaxy before the merger, using Monte Carlo (MC) simulations, we successfully explained the observed metallicity distribution in these substructures. These results are a contribution to the investigation of metallicity gradients in dwarf galaxies which is important for galaxy evolution in general.
DEEP IMAGING WITH MILANKOVIĆ TELESCOPE: LINKING MERGER HISTORY TO KINEMATICS OF ELLIPTICAL GALAXIES
Authors: Ebrová Ivana , Bílek Michal , Lalović Ana , K. Yıldız Mustafa , Duc Pierre-Alain , Mašek Martin , Prouza Michael
Published: December 2024

Abstract. Kinematical and morphological features observed in early-type galaxies provide valuable insights into the evolution of their hosts. We studied the origin of prolate rotation (i.e., rotation around the long axis) in Illustris large-scale cosmological hydrodynamical sim- ulations. We found that basically all the simulated massive prolate rotators were created in relatively recent major mergers of galaxies. Such mergers are expected to produce tidal features such as tails, shells, asymmetric stellar halos. We investigated deep optical images of prolate rotators, including newly obtained data from the Milankovic telescope (Astronomical Station Vidojevica), revealing signs of galaxy interaction in all of them. This correlation proves to be statistically very significant when compared with a general sample of early-type galaxies from the MATLAS deep imaging survey. In an ongoing project, we use the Milankovic telescope to assemble deep images of the complete sample of all known nearby massive prolate rotators. The most frequent tidal features among the prolate rotators happen to be shells. We developed methods to calculate the probable time of the merger from optical images. This will allow us to compare the merger history of the sample with predictions from Illustris. Our plan is to expand these methods to even larger samples of shell galaxies supplied by upcoming large surveys like LSST at Rubin Observatory. This will provide an unprecedented amount of statistically significant data on the recent merger history of our Universe and allow extensive investigation of the impact of mergers to a wide range of other astrophysical phenomena.
DYNAMICS OF SPIRAL GALAXIES IN NONLINEAR REGIME - NONLINEAR SOLITARY WAVES IN ACCRETION DISK
Authors: Vukčević Miroslava , Bon Edi , Bon Nataša
Published: December 2024

Abstract. Theory of accretion disk is subject of several different theoretical models. Here, we list all important effects that can influence the accretion disk dynamics. For each effect, we propose nonlinear solution that is able to overcome linearly unstable structure. Such a stable, long lasting structure is useful in many aspects, but the most important one is possibility to compare to observed parameters relevant for the existence of the nonlinear solution.
MUSE-NFM OBSERVATIONS OF THE CIRCINUS ACTIVE GALACTIC NUCLEUS
Authors: Knežević Sladjana , Kakkad Darshan , Stalevski Marko , Kishimoto Makoto , Asmus Daniel , P. A. Vogt Frédéric
Published: December 2024

Abstract. We present integral-field spectroscopic observations of the Circinus galaxy performed with the MUSE narrow field mode on the VLT. The spatial resolution of ∼ 0.1 within the field-of-view of 7.5 × 7.5 enabled us to zoom into the ionized gas kinematics within the central ∼ 100 pc of the AGN. The analysis revealed that the systemic component resembles the ionization cone structure seen in larger scales, while the outflowing component shows a "tuning-fork" morphology: a collimated structure originating near the AGN location and extending in the north-western direction before it splits into two arms at around 30 pc from the AGN. We speculate that the origin of the collimated outflow might be due to the radio jet and ISM interactions on parsec scales, while a presense of a dust clump at the tip of the collimated part of the outflow might explain its fragmentation. The estimated total instantaneous and time-average mass outflow rates suggests that the observed outflow is not expected to regulate star formation within the ∼ 100 pc. BPT diagram revealed that the dominant source of ionization is the AGN. In addition, we will present also the morphology and kinematics of the coronal gas traced by the high-ionization forbidden lines.
THE INFLUENCE OF INTERACTIONS OF DISTANT GALAXIES ON THEIR NON-THERMAL RADIO EMISSION
Authors: Pavlović Marina , Prodanović Tijana
Published: December 2024

Abstract. It has been established that a strong linear correlation exists between the thermal far-infrared (FIR) and non-thermal radio emissions of star-forming galaxies. Recent research on this correlation at high redshifts has revealed that it is evolving as redshifts increase. This paper explores potential physical factors contributing to this correlation’s evolution, with one likely explanation being galaxy interactions. To investigate this hypothesis, a sample of dusty star-forming galaxies from the COSMOS field, up to a redshift of z = 3.5, was carefully selected. The sample was divided into two subsets based on morphological types: disk and irregular galaxies. Here we use galactic morphology as an indicator of past or ongoing interactions, as irregular galaxy shapes are often the result of collisions or close encounters. The evolution of the correlation with redshift was analyzed separately for each subset. This study lack of indication of redshift evolution in the FIR-radio correlation for both disk and irregular galaxy subsets. However, the analysis did reveal a hint that irregular galaxies exhibited a lower mean correlation parameter, qFIR, suggesting that they might influence the correlation's evolution if their prevalence in the sample increases at higher redshifts.
ABOUT SOME NEAR-EARTH ORBITS181
Authors: Todorović Nataša , Knežević Nikola
Published: December 2024

Abstract. The population of near-Earth objects (NEOs) currently counts more than 30 000 known members. In general, NEOs have chaotic orbits, short lifetimes, and often an unidentified dynamical background. In this work, we discuss the discrepancy in the literature about the dynamical connection between the main belt asteroid 2 Pallas and the Apollo asteroid 3200 Phaethon, the parent body of the Geminides. We repeat the results on the Pallas-Phaethon link, using a still-developing Python platform running in REBOUND, and illustrate its sensitivity to some parameters of the numerical integration.
THE EQUATION BETWEEN 3-BODY MEAN MOTION RESONANCES AND YARKOVSKY DRIFTS ON ECCENTRICITIES IN THE RANGE (0.1, 0.2)
Authors: Milić Žitnik Ivana
Published: December 2024

Abstract. We studied the motion of asteroids across the 3-body mean motion resonances (MMRs) with Jupiter and Saturn and with the Yarkovsky drift in the semimajor axis of the asteroids. The research was conducted using numerical integrations performed using the Or- bit9 integrator with 72,000 test asteroids. We calculated time delays, dtr, caused by the six 3-body MMRs on the mobility of test asteroids with 10 positive and 10 negative Yarkovsky drifts, which are reliable for Main Belt asteroids. Our final results considered only test aster- oids that successfully crossed over the MMRs without close approaches to the planets. We devised equations that approximately describe the functional relation between the averagetime (dtr) spent in the resonance, the strength of the resonance SR, and the semimajor axis drifts da/dt (positive and negative) with the orbital eccentricities of asteroids in the range (0.1, 0.2). Comparing the values of (dtr) obtained from the numerical integrations and from the derived functional relations, we analysed average values of (dtr) in all 3-body MMRs for every da/dt. The main conclusion is that the analytical and numerical estimates of the average time (dtr) are in very good agreement, for both positive and negative da/dt. Finally, this study shows that the functional relation we obtain for 3-body MMRs for orbital eccentricities of asteroids in the range (0.1, 0.2) is analogous to that previously obtained fororbital eccentricities of asteroids in the range (0, 0.1) in Milić Žitnik 2021.
THE LIFE AND WORK OF ELIA MILLOSEVICH (1848-1919)
Authors: Arbutina Bojan
Published: December 2024

Abstract. In this contribution we briefly present the biography and professional activities of the Italian astronomer Elia Millosevich, professor of nautical astronomy at the Royal Institute of the Merchant Navy in Venice and later the director of the Roman College Observatory, whose family originates from the town of Dobrota in Boka Kotorska, present-day Montenegro.
DEPARTMENT OF ASTRONOMY AT PETNICA SCIENCE CENTER: 2021-2023
Authors: Milić Damnjan , Milošević Stanislav , Savić Nikola
Published: December 2024

Abstract. The main topic of our review will be the activities held by the Astronomy Department at the Petnica Science Center (PSC) from 2021 to 2023. The focus of the As- tronomy Department has been on high school students as participants and the programs created for them. During the whole of the educational cycle at the Astronomy Department, conceived as a two-year program, participants are introduced to the fundamentals of astron- omy and its research methodology in the first year, which ultimately leads to the completion of their first research projects by the end of the second year. Therefore, in this review, we will present the current structure of the Astronomy Department at PSC, the topics of the participants’ research projects, some of the other activities carried out during the mentioned period, and the outline of our plans for the future.
SERBIAN ASTRONOMICAL JOURNAL IN THE 2003-2023 PERIOD
Authors: Arbutina Bojan , Jovanović Milena , Urošević Dejan
Published: December 2024

Abstract. The bibliographic and citation data for the Serbian Astronomical Journal in the 2003-2023 period are presented. We report on the journal acceptance rate, geographical distribution of authors and impact factor, along with other metrics.
OPTICAL OBSERVATIONS OF SHOCK FILAMENTS IN TYCHO'S SUPERNOVA REMNANT
Authors: Knežević Sladjana , Schulze Steve , Méndez-Abreu Jairo , Van De Ven Glenn , Morlino Giovanni
Published: December 2024

Abstract. We present observations of the supernova remnant Tycho obtained with OSIRIS at the Gran Telescopio Canaria. With its large field-of-view (4t×4t), spatial sampling of 0.25tt and spectral resolution of 650 kms−1, we covered a large portion of the remnant and resolved the broad Hα component (∼ 1000 km s−1). Previously, we observed the narrow (∼ 10 km s−1) and intermediate (∼ 100 km s−1) component in the same region using GHαFaS on the William Herschel Telescope. Observing all three line components at exactly the samelocations along the filaments and applying shock models give more precise information on the overall conditions in the shock, and enable us to quantify cosmic-ray properties.
LOCAL KINEMATICS OF A GAIA SAMPLE OF STARS
Authors: Stojanović Milan , Ninković Slobodan
Published: December 2024

Abstract. A sample of stars from the Solar neighbourhood which are within 100 pc from the Sun is formed. For all of them the newest astrometric data, products of the GAIA Mission, and line-of-sight velocities are available. The objective is to examine the local kinematics bearing in mind the usual classification into thin disc, thick disc and halo. For this purpose a catalogue of galactocentric orbits is formed. The preliminary results, among others, indicate a sufficiently significant rotation of the halo at the Sun.
ОД МЕТЕОРОЛОШКЕ ОПСЕРВАТОРИЈЕ ДО ХИДРОМЕТЕОРОЛОШКОГ ЗАВОДА СРБИЈЕ
Authors: Максимовић С.
Published: December 2024

In this paper the history of development of meteorological science and praxis is chronologically presented, beginning with the Aristotelian Meteorology, written in the fourth century BC. The earliest manuscripts concerning climate extrema in the territory of Serbia originate from the XIV century. They were written by Orthodox monks. Systematic observations, as the first organized form of meteorological activity, in the territory of the Principality of Serbia started in mid-XIX century, which is the time when the services and first observatories in meteorology were founded and started its activity in many European countries. All scientists and enthusiasts who have significantly contributed to the development and functioning of meteorological facilities in the territory of Serbia are mentioned.
АСТРОНОМСКА ОПСЕРВАТОРИЈА КАО АМБИЈЕНТАЛНА ЦЕЛИНА: СИНТЕЗА НАУКЕ, АРХИТЕКТУРЕ И ПРИРОДЕ – ОБАВЕЗА И НЕОПХОДНОСТ САВРЕМЕНОГ ДРУШТВА
Authors: Скочајић Д. , Фолић Н. , Мијатовић В.
Published: December 2024

Astronomical observatory in Belgrade, in addition to the need for development and financing of research activities, advocates for the preservation of rich cultural, historical and natural heritage. The protection of the entire ambient unit can be achieved through the harmony of architecture and nature. Ambient unite means the environment designed for man, the atmosphere in which he lives and works and his surroundings. Ambience includes several terms, i.e. elements, from "atmosphere" in the sense of the carefully chosen location of buildings, through the effects that natural or artificial sources of light, sounds, heat, etc. as well as the relationship between architectural objects and the existing environment (Maldini, 2012). Through examples from around the world, the spatial development of astronomical observatories was analyzed with the need for improvement the existing state of the ambient environment of the Observatory in Belgrade. This paper refers to the synergy of architecture, nature and science in the setting of the Astronomical Observatory in Belgrade in one of the oldest scientific institutions in Serbia, which began its work in 1932 at the location known as "elevation 253" on the "Laudanov ditch" of the hill "Veliki Vračar".
КОМПЛЕКС АСТРОНОМСКЕ ОПСЕРВАТОРИЈЕ - ИЗАЗОВИ САВРЕМЕНЕ КОНЗЕРВАЦИЈЕ
Authors: Шевић А.
Published: December 2024

Ever since the first efforts to establish a modern astronomical observatory in this area, back in 1887, thanks to the efforts of scientist and professor Milan Nedeljković, this institution was established as a respectable scientific institution. Although it did not have its own permanent facility and space until 1929, with the construction of the modern complex of the Astronomical Observatory in East Vračar (now Zvezdara), all conditions were met for the Observatory in Belgrade to continue its exceptional scientific work. The complex project program was successfully realized by the architect Jan Dubovi, by building a complex with several Pavilions for observation and measurement, the Administrative Building and accompanyingfacilities that had the task of making the life and work of astronomers and other scientists easier and better. The development of astronomical science, technical and technological achievements have led to the gradual cessation of the use of objects and instruments for the purpose of obtaining relevant scientific results. In the last more than thirty years, part of the complex has been transformed in an inadequate way, which may have permanently destroyed and changed the architectural values of some authentic buildings. Preservation and restoration of buildings, reconstruction, rehabilitation and revitalization of the entire complex used by the Astronomical Observatory are only part of the overall process of its renewal.
Spectral line broadening and the corresponding databases
Authors: Dimitrijević M.S.
Published: December 2024

Profiles of spectral lines broadened by collisions with charged particles (Stark broadening) and neutral atoms (Van der Waals and resonance broadening) are needed for determination of various quantities and solution of different problems in astrophysics, physics and technology, as for example modelling of stellar plasma, analysis and synthesis of spectral lines, calculations of absorption coefficient, opacity, radiative transfer, abundance determination, laboratory plasma diagnostic, lasers and laser produced plasma, inertial fusion experiments and modelling and optimisation of plasmas in technology.In this contribution we will present databases containing data relevant to the broadening of atomic and ionic spectral lines, needed for above mentioned topics. We will discuss and describe Atomic Spectral Line Broadening Bibliographic Database of National Institute of Standards and Technology (NIST - Washington); the Vienna Atomic Line Database (VALD), a collection of atomic and molecular transition parameters of astronomical interest (Piskunov et al. 1995); the collection of databases of Paris Observatory: MOLAT Atomic and Molecular Data containing, among others, three databases of interest for line profiles: BALSS (Bibliography of Atomic Line Shapes and Shifts), Griem's tables (Griem 1974) and STARK-B database containing data on Stark broadening parameters (Sahal-Bréchot et al. 2015). Additionally we will present and VAMDC, european Virtual Atomic and Molecular Data Center. Also, we will dicuss where the data on spectral line profiles may be used. - FULL TEXT available in PDF.
Pseudo harmonic oscillator potential
Authors: Iacob F.
Published: December 2024

It is discussed and shown an analytical results for a chemical potential that can be assimilated to a harmonic oscillator. It can be applied to describe particles that are in a trap created in the plasma medium. Depending on the specificity of the bounding interaction this potential can be modified according to the states of a particle trapped inside. Unlike the classical harmonic oscillator potential, which is an infinitely deep well, the presented potential is tunable and the trapped particle can escape above a certain energy. This model can be used to describe particle trapping, such as electrostatic trapping in plasma. This is an essential effect that should be added to the description of the Dynamics of the plasma fluid and other collective systems. Furthermore, a damped harmonic oscillator can be a successful model to describe the adiabatic cooling process of a trapped atomic/molecular system.This presentation's goals are to illustrate the potential's analytical construction and demonstrate how its parameters can be changed. - FULL TEXT available in PDF.
Reactive collisions between electrons and molecular cations. Applications in astrophysics and cold plasmas modelling
Authors: Pop N. , Djuissi E. , Mezei J.Z. , Schneider I.F.
Published: December 2024

Dissociative recombination (DR) of molecular cations with electrons is a major elementary process in the kinetics and in the energy balance of astrophysical ionized media (supernovae, interstellar molecular clouds, planetary ionospheres), fusion plasmas in the divertor region, hypersonic entry plasmas and in many other cold media of technological interest.Using Multichannel Quantum Defect Theory (MQDT), cross sections and Maxwell rate coefficients have been obtained for DR and ro-vibrational transition (RVT) as ro-vibrational excitation (RVE, inelastic collisions), ro-vibrational de- excitation (RVdE, super-elastic collisions) of H2+ and HD+ for numerous ro- vibrational states of the ion. The computational results obtained are in reasonable agreement with experimental data (Motapon et al., 2014; Epée et al., 2016).A complete set of vibrationally resolved rate coefficients for BeH+ cation and its isotopomers: BeD+, BeT+ reactive collisions with electrons below the ion dissociation threshold has been provided (Niyonzima et al., 2017; Niyonzima et al., 2018; Pop et al., 2021).The resulting data are useful for the modeling of the kinetics of the Early Universe and of the magnetic-confinement-fusion-edge plasma.Our previous studies of DR, vibrational excitation/de-excitation and dissociative excitation (DE) of the BeH+ ion, based on the MQDT, are extended to collision energies above the dissociation threshold (up to 12 eV) by increasing the number of dissociative states for all molecular symmetries (Djuissi et al., 2024). - FULL TEXT available in PDF.
Soft x-ray photoelectron-photoion-photoion coincidence (PEPIPICO) spectroscopy of isolated molecular systems at PLEIADES beamline (SOLEIL synchrotron)
Authors: Milosavljevic A.R. , Nicolas C. , Robert E. , Bozek J.
Published: December 2024

The soft X-ray beamline PLEIADES at Synchrotron SOLEIL facility (France) will be presented, with the focus on the energy and angle resolved (Auger) electron- ion coincidence permanent setup (EPICEA). The EPICEA allows for photoelectron-photoion-photoion coincidence (PEPIPICO) and Auger electron- photoion-photoion coincidence (AEPIPICO) spectroscopy (PLEIADES, 2019; Ganguly et al., 2022). The setup consists of a double toroidal electron analyzer (DTA) (Miron et al., 1997) and a 3D focusing ion TOF spectrometer. Electrons emitted at an angle of 54.71 are accepted by the DTA and selected according to their predetermined pass energy (Ep). The detection electron kinetic energy window is about 12% of the defined Ep, whereas the energy resolution is about 1%of the Ep. After exiting the DTA, the electrons are recorded by a delay-line position sensitive detector (DLD40, Roentdek GmbH), where the distance of the electron position from the center is inversely proportional to its kinetic energy. The interaction region is placed in a zero- electric-field space between two extraction grids. The detection of an electron triggers a pulsed field that accelerates the ions toward a hexagonal delay-line detector (HEX75, Roentdek GmbH) placed after the TOF drift tube. The positions on the detector and time of flight of all extracted ions are recorded. Additionally, a pulse generator (Stanford DG645) was used to produce random triggers, which extract ions present in the interaction without a coincident electron event, thus allowing to analyze the background ion signal recorded due to false coincidences. In the present lecture, example results will be presented for several different molecular targets that are interesting for a range of research topics. - FULL TEXT available in PDF.
Kinetic and fluid studies on Resistive Plate Cambers operated with new eco-friendly gas mixtures
Authors: Dujko S. , Simonović I.B. , Bošnjaković D.V.
Published: December 2024

Resistive plate chambers (RPCs) are parallel plate gaseous detectors commonly used for timing and triggering purposes in many high-energy physics experiments. RPCs are employed at CERN-LHC (Large Hadron Collider) experiments due to their excellent time resolution, high-rate capability, and relatively low production cost (Rigoletti et al. 2020). They also play a key role in direct measurements of muons in air showers (Abreu et al. 2018) and in some neutrino observatories (Kumar et al. 2017). RPCs are operated with a gas mixture consisting of C2H2F4 (between 90% and 95%), a smaller fraction of i-C4H10 (around 5%) and SF6 (usually between 0.3% and 1%). C2H2F4 and SF6 are well-known greenhouse gases with a global warming potential of respectively 1430 and 22800. The substitution of C2H2F4 and SF6 with environmentally friendly alternatives is one of the major challenges in current RPC technology. C2H2F4 can be substituted with either a mixture of C2H2F4 and CO2, or a mixture of C3H2F4 and CO2, or eventually a mixture of C3H2F4 and He (Rigoletti et al. 2020, Abbrescia et al. 2024). On the other hand, CF3I, C4F7N and C5F10O were considered as alternatives to SF6 (Guida et al. 2022). The performance of the detector, including detection efficiency, time resolution, and streamer occurrence, with these gases and mixtures has only been tested experimentally so far. This work presents the first comprehensive modelling study of RPCs that operate with the new generation of environmentally friendly gases and corresponding mixtures.We approached the problem in three stages. We start by presenting completeand consistent cross-section sets for electron scattering in C2H2F4 and C3H2F4. A cross-section set for electron scattering in C3HF5 is also developed, as this gas could also be considered as an alternative to C2H2F4. The accuracy of cross-section sets was tested and validated through a series of comparisons between swarm data calculated using a numerical solution of Boltzmann’s equ ... - FULL TEXT available in PDF.
Terminator variations of VLF/LF amplitudes - observational techniques and case studies
Authors: Eichelberger H. , Nina A. , Boudjada M.Y. , Kolarski A. , Veselinović N.B. , Nico G. , Biagi P.F. , Srećković V.A.
Published: December 2024

AbstractThe VLF/LF Earth-ionosphere waveguide enables the remote detection of important variabilities related to environmental and solar processes. Two case studies have been considered with medium and high solar activities, both recorded by Belgrade (Serbia) and Graz (Austria) stations. This study shows the existence of electric field amplitude wave phenomena with periods of ~500 sec during terminator times. Our findings underscore the importance of measurement networks for future surveys. - FULL TEXT available in PDF.
Specific changes in VLF signals induced by astrophysical and geophysical phenomena: possibility of applying machine learning in statistical analyses
Authors: Nina A. , Butka P. , Kolarski A. , Srećković V.A. , Sarnovský M. , Bednár P. , Popović L.Č.
Published: December 2024

AbstractIn this paper, we present examples of changes in VLF signals used to monitor the lower ionosphere. The mentioned changes in signal characteristics are caused by astro- and geo-phenomena. We indicate the possibility of applying machine learning in statistical analysis of these changes, which is the basis of the work on the Serbian Slovak bilateral project Detection of astrophysical and geophysical phenomena from VLF radio measurements using machine learning methods. - FULL TEXT available in PDF.