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An investigation into bipolar fuzzy hoop algebras and their applications
Get PDFThis paper introduces bipolar fuzzy sub-hoops and bipolar fuzzy filters within
hoop algebras, extending fuzzy logic to incorporate both positive and negative membership
degrees. We define these structures, explore their algebraic properties, and establish
their interplay through rigorous theorems. Key results include characterizations of bipolar
fuzzy filters via level sets and conditions under which they become implicative filters.
These findings enhance the theoretical framework of many-valued logic and offer practical
applications in decision-making, image processing, and spatial reasoning under uncertainty.
Our work provides a foundation for advanced fuzzy systems handling complex,
contradictory information
Amplifying UHECR arrival direction information using mass estimators at the Pierre Auger Observatory
Get PDFThe origin of Ultra-High-Energy Cosmic Rays (UHECRs) is one of the biggest mysteries in modern astrophysics. Since UHECRs are deflected by Galactic and extragalactic magnetic fields, their arrival directions do not point to their sources. Previous analyses conducted on the arrival directions of high-energy events (E ≥ 32 EeV) recorded by the Surface Detector of the Pierre Auger Observatory have not shown significant anisotropies. The largest excess found in the first 19 years of data - at the 4.0 sigma level - is in the region around Centaurus A, and it is also the driving force of a correlation of UHECR arrival directions with a catalog of Starburst Galaxies, which is at the 3.8 sigma level. Since UHECRs are mostly nuclei, the lightest ones (least charged) are also the least deflected. While the mass of the events can be estimated better using the Fluorescence Detector of the Pierre Auger Observatory, the Surface Detector provides the necessary statistics needed for astrophysical studies. The introduction of novel mass-estimation techniques, such as machine learning models and an algorithm based on air-shower universality, will help identify high-rigidity events in the Surface Detector data of the Pierre Auger Observatory. With this work, we present how event-per-event mass estimators can help enhance the sensitivity in the search for anisotropies in the arrival directions of UHECRs at small and intermediate angular scales using simulations
The (un)expectedly stacked prefixes in Slovenian
Get PDFWhen a Slavic verb occurs with multiple prefixes their order is often claimed to follow certain restrictions of a fairly formal character. Firstly, lexical prefixes, which can modify the argument structure of the verb and contribute idiosyncratic interpretations, are always found adjacent to the verbal root, while superlexical prefixes, which do not alter the argument structure and whose interpretative contribution is adverbial, can be stacked over the lexicals. And secondly, when multiple superlexicals stack on a verbal stem, they follow a fixed order. We set out to test these two generalizations with a corpus study. We find that there exist a number of verbs which seem to have more than one lexical prefix, in direct contradiction of the standard assumptions about prefixation
A 1.8 m class pathfinder Raman LIDAR for the Northern Site of the Cherenkov Telescope Array Observatory
Get PDFThe Barcelona Raman LIDAR (BRL) will provide continuous monitoring of the aerosol extinction profile along the line of sight of the Cherenkov Telescope Array Observatory (CTAO). It will be located at its Northern site (CTAO-N) on the Observatorio del Roque de Los Muchachos. This article presents the performance of the pathfinder Barcelona Raman LIDAR (pBRL), a prototype instrument for the final BRL. Power budget simulations were carried out for the pBRL operating under various conditions, including clear nights, moon conditions, and dust intrusions. The LIDAR PreProcessing (LPP) software suite is presented, which includes several new statistical methods for background subtraction, signal gluing, ground layer and cloud detection and inversion, based on two elastic and one Raman lines. Preliminary test campaigns were conducted, first close to Barcelona and later at CTAO-N, albeit during moonlit nights only. The pBRL, under these non-optimal conditions, achieves maximum ranges up to about 35 km, range resolution of about 50 m for strongly absorbing dust layers, and 500 m for optically thin clouds with the Raman channel only, leading to similar resolutions for the LIDAR ratios and Ångström exponents. Given the reasonable agreement between the extinction coefficients obtained from the Raman and elastic lines independently, an accuracy of aerosol optical depth retrieval in the order of 0.05 can be assumed with the current setup. The results show that the pBRL can provide valuable scientific results on aerosol characteristics and structure, although not all performance requirements could be validated under the conditions found at the two test sites. Several moderate hardware improvements are planned for its final upgraded version, such as gated PMTs for the elastic channels and a reduced-power laser with a higher repetition rate, to ensure that the data acquisition system is not saturated and therefore not affected by residual ringing
Reconstructing air-shower observables using a universality-based model
Get PDFAir-Shower universality describes the regularity in the longitudinal, lateral, and energy distributions of electromagnetic shower particles, as motivated by solutions of the cascade equations. To reconstruct air-shower observables from ultra-high-energy cosmic rays, we employ a universality-based model of shower development that incorporates hadronic particle components. Depending on the input parameters, the model can be used, for example, to estimate the depth of the shower maximum or the number of muons on event level. In this context, we present the expected performance for the reconstruction using air-shower simulations and data from the Pierre Auger Observatory
Observation of the Shadows of the Moon and Sun Using the Pierre Auger Observatory at an Average Energy of ▫▫ eV
No full textThe interaction of cosmic rays with celestial bodies such as the Moon or the Sun
produces a shadow in the arrival direction distribution of the cosmic rays reaching
the Earth. Such deficits from an isotropic flux have been observed by astroparticle
observatories below energies of 1 PeV. Above this energy, measurements were
limited due to the low number of events as a result of the steeply falling cosmic-ray
flux with energy. With more than 10.6 million events recorded during 20 years
of operation of the Pierre Auger Observatory, we report the first observation of the
shadow of the Moon at an average energy of 700 PeV with a maximum significance
above 3σ. The shadow is an end-to-end check that the celestial directions are
correctly reconstructed from the air shower data, and it is used here to derive
the effective angular resolution for this dataset. Additionally, we present the results
of a similar study on the shadow of the Sun
Chemical and optical properties of biomass burning and diesel emissions and their atmospheric aging
No full textEmissions from biomass burning (BB) and diesel combustion significantly impact air quality, health and climate by releasing pollutants. However, due to variability in combustion sources and efficiency, and emission aging, their aerosol\u27s composition and optical properties remain poorly understood and underrepresented in climate and air quality models. This study investigated the chemical and physical properties of BB aerosol emissions using advanced instrumentation in the EUPHORE simulation chamber. Emissions from different wood types (including mixtures with diesel exhaust) were analyzed, considering flaming and smoldering combustion, and their evolution under day and night conditions.
Results indicated that combustion phase had a greater influence on emissions than wood type. Flaming combustion and diesel exhaust produced similar elemental carbon (EC) emissions (0.55 g/kg fuel and 0.46–0.73 g/kg fuel, respectively) while smoldering yielded lower EC (0.1–0.37 g/kg fuel) and higher organic carbon (OC), leading to higher OC/EC ratios (53 ± 20 g/kg fuel) than flaming and diesel fumes (1.5 ± 0.8 and 0.6 ± 0.1 g/kg fuel, respectively). Smoldering emissions contained more complex, higher molecular weight organics, with more harmful effects than flaming. Daytime aging promoted formation of highly-oxidized organic compounds, while nighttime aging, driven by nitrate radicals, formed nitro-aromatic compounds, associated with genotoxicity and carcinogenicity. Both aging processes also increased aerosol absorption and scattering, affecting climate-relevant properties.
This study provides one of the most comprehensive chamber-based analyses of BB and diesel-related emissions and their atmospheric evolution, integrating aerosol chemical composition and optical properties. The results contribute to understanding the impact of BB on air quality, health and climate, enhancing models and informing effective mitigation strategies