Search

The rapid and accurate detection of biochemical compositions in fish is a crucial real-world task that facilitates optimal utilization and extraction of high-value products in the seafood industry. Raman spectroscopy provides a promising solution for quickly and non-destructively analyzing the biochemical composition of fish by associating Raman spectra with biochemical reference data using machine learning regression models. This paper investigates different regression models to address this task and proposes a new design of Convolutional Neural Networks (CNNs) for jointly predicting water, protein, and lipids yield. To the best of our knowledge, we are the first to conduct a successful study employing CNNs to analyze the biochemical composition of fish based on a very small Raman spectroscopic dataset. Our approach combines a tailored CNN architecture with the comprehensive data preparation procedure, effectively mitigating the challenges posed by extreme data scarcity. The results demonstrate that our CNN can significantly outperform two state-of-the-art CNN models and multiple traditional machine learning models, paving the way for accurate and automated analysis of fish biochemical composition.

Recent experimental data from space-based instruments of the DAMPE and CALET collaborations have shown that the energy spectrum of protons has a new feature, a break in the $\sim 10$ TeV region. In this energy range, the spectrum index of the observed particles varies from $-2.6$ to $-2.9$. The purpose of this work is to establish the local sources's position and age that determine this break, the index of the proton generation spectrum in them, as well as the astrophysical interpretation of the results obtained in the DAMPE and CALET experiments. Within the framework of the model of nonclassical diffusion of cosmic rays developed by the authors, which has break due to the propagation of particles in a sharply inhomogeneous (fractal type) galactic medium, it is shown that break in this energy range is formed by tevatron located at a distance of $\sim 120$ pc from the Earth. These source, whose age is $\sim 5 \cdot 10^5$ years, generate particles with a spectrum index $\sim 2.7$. The power-law behavior of the proton spectrum before and after the break, soft spectrum of particles generation in the source, first obtained in the DAMPE and CALET experiments, should be considered as an indication of the need to revise the standard paradigm accepted today about the sources of cosmic rays, mechanisms of particle acceleration in them and particles propagation in the Galaxy., Comment: 13 pages, 5 figures, 1 table, The 4th International Symposium on Cosmic Rays and Astrophysics (ISCRA-2023)

The paper discusses an approach that made it possible to estimate the distance to the nearest pevatrons, which form a knee in the spectrum of the cosmic ray nucleon component of about $4$ PeV. It is based on the spectra of nucleons and electrons obtained by the authors in the framework of the superdiffusion model of nonclassical cosmic rays diffusion, which have a knee, on the assumption that nucleons and electrons are accelerated by the same type sources and their propagation in an inhomogeneous turbulent galactic medium is characterized by the same diffusion coefficient, and also on the knee in the spectrum of the electronic component in the region of $0.9$ TeV, established in the DAMPE experiment. It is shown that pevatrons, which form a knee in the spectrum of the cosmic ray nucleon component of about $4$ PeV, are located at distances of the order of $0.75$ kpc from the Earth., Comment: 12 pages, 3 figures, 2 tables, The 4th International Symposium on Cosmic Rays and Astrophysics (ISCRA-2023)

The physical motivations, present status, main results in study of cosmic rays and in the field of gamma-ray astronomy as well future plans of the TAIGA-1 (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) project are presented. The TAIGA observatory addresses ground-based gamma-ray astronomy and astroparticle physics at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. The pilot TAIGA-1 complex is located in the Tunka valley, ~50 km west from the southern tip of the lake Baikal., Comment: Submission to SciPost Phys. Proc., 10 pages, 2 figures

The corrected dependence of the mean depth of the EAS maximum $X_{max}$ on the energy was obtained from the data of the Tunka-133 array for 7 years and the TAIGA-HiSCORE array for 2 years. The parameter $\langle\ln A\rangle$, characterizing the mean mass compositon was derived from these results. The differential energy spectrum of primary cosmic rays in the energy range of $2\cdot 10^{14}$ - $2\cdot 10^{16}$\,eV was reconstructed using the new parameter $Q_{100}$ the Cherenkov light flux at the core distance 100 m.}, Comment: 6 pages, 3 figures, Submitted to SciPost Phys.Proc

The Tunka-Grande experiment is a scintillation array with about 0.5 sq.km sensitive area at Tunka Valley, Siberia, for measuring charged particles and muons in extensive air showers (EASs). Tunka-Grande is optimized for cosmic ray studies in the energy range 10 PeV to about 1 EeV, where exploring the composition is of fundamental importance for understanding the transition from galactic to extragalactic origin of cosmic rays. This paper attempts to provide a synopsis of the current results of the experiment. In particular, the reconstruction of the all-particle energy spectrum in the range of 10 PeV to 1 EeV based on experimental data from four observation seasons is presented., Comment: 7 pages, 3 figures, submission to SciPost Phys. Proc

Recent works leveraging learning to enhance sampling have shown promising results, in particular by designing effective non-local moves and global proposals. However, learning accuracy is inevitably limited in regions where little data is available such as in the tails of distributions as well as in high-dimensional problems. In the present paper we study an Explore-Exploit Markov chain Monte Carlo strategy ($Ex^2MCMC$) that combines local and global samplers showing that it enjoys the advantages of both approaches. We prove $V$-uniform geometric ergodicity of $Ex^2MCMC$ without requiring a uniform adaptation of the global sampler to the target distribution. We also compute explicit bounds on the mixing rate of the Explore-Exploit strategy under realistic conditions. Moreover, we also analyze an adaptive version of the strategy ($FlEx^2MCMC$) where a normalizing flow is trained while sampling to serve as a proposal for global moves. We illustrate the efficiency of $Ex^2MCMC$ and its adaptive version on classical sampling benchmarks as well as in sampling high-dimensional distributions defined by Generative Adversarial Networks seen as Energy Based Models. We provide the code to reproduce the experiments at the link: https://github.com/svsamsonov/ex2mcmc_new., Comment: arXiv admin note: text overlap with arXiv:1111.5421 by other authors

A wide-angle Cerenkov array TAIGA-HiSCORE (FOV $\sim$0.6 sr), was originally created as a part of TAIGA installation for high-energy gamma-ray astronomy and cosmic ray physics. Array now consist on nearly 100 optical stations on the area of 1 km$^2$. Due to high accuracy and stability ($\sim$1 ns) of time synchronization of the optical stations the accuracy of EAS arrival direction reconstruction is reached 0.1$^\mathrm{o}$. It was proven that the array can also be used to search for nanosecond events of the optical range. The report discusses the method of searching for optical transients using the HiSCORE array and demonstrates its performance on a real example of detecting signals from an artificial Earth satellite. The search for this short flares in the HiSCORE data of the winter season 2018--2019 is carried out. One candidate for double repeater has been detected, but the estimated probability of random simulation of such a transient by background EAS events is not less than 10%, which does not allow us to say that the detected candidate corresponds to a real astrophysical transient. An upper bound on the frequency of optical spikes with flux density of more than $10^{-4} \mathrm{erg/s/cm}^2$ and a duration of more than 5\,ns is established as $\sim 2 \times 10^{-3}$ events/sr/hour., Comment: 15 pages, 6 figures, reported at the conference ISCRA-2021, Accepted for publication in Physics of Atomic Nuclei

The progress and the chronology in understanding the influence of electron correlations on the electronic structure of atoms and the dynamics of atomic processes are reviewed focusing on benchmark rare-gas atoms. The contributions and the chronological development of Photon-Induced Fluorescence Spectroscopy (PIFS), measuring {} dispersed-fluorescence emission cross sections upon excitation by single photons provided by monochromatized synchrotron radiation is described. Selected experimental results obtained by complementary techniques are also discussed for comparison. The basic suites of computer programs used for the investigation of the many-electron effects in atoms and the obtained results are analyzed. Special attention is paid to the Configuration Interaction Pauli-Fock approximation with Core Polarization (CIPFCP) method used to interpret the PIFS data., Comment: 88 pages, 54 figures, 344 bibliography items

The absolute generalized cross sections and angular distribution parameters of photoelectrons for the two-photon above threshold $3p$-ionization of Ar were calculated in the exciting photon energy range from 15.76 to 36 eV. The correlation function technique developed earlier was extended for the case when an intermediate-state function is of a continuum-type. We show that two-photon ionization of Ar near the $3p^{4}$ threshold to a large extent is determined by the $(3p\dashrightarrow\varepsilon d)^{2}$ two-photon absorption via the giant resonance. This many-electron correlation causes (i) an increase of the photoionization cross sections by more than a factor of 3; (ii) the appearance of resonances in the exciting-photon energy range of the doubly-excited states. The predictions are supported by a good agreement between length and velocity results obtained after taking into account of the higher-order perturbation theory corrections., Comment: 11 pages, 8 figures, 26 bibliography

A detailed theoretical analysis of the 1s photoionization of neon is presented. It is found that the most significant many-electron correlation in computing photoionization of inner shells is the rearrangement of the outer shells caused by the inner vacancy. Further noticeable effects are: (i) the polarization of the ion core by the outgoing photoelectron and (ii) the coherent effect of double excitation/ionization. The core polarization increases the photoionization cross section by about 10% at the 1s threshold, and the coherent excitation results in further increases by about 5%. Incoherent excitation of the satellite channel leads to an additional 10% increase in the photoabsorption cross section in the double-ionization threshold region., Comment: 6 pages, 3 figures, 22 bibliography

Likelihood training and maximization-based decoding result in dull and repetitive generated texts even when using powerful language models (Holtzman et al., 2019). Adding a loss function for regularization was shown to improve text generation output by helping avoid unwanted properties, such as contradiction or repetition (Li at al., 2020). In this work, we propose fine-tuning a language model by using policy gradient reinforcement learning, directly optimizing for better generation. We apply this approach to minimizing repetition in generated text, and show that, when combined with unlikelihood training (Welleck et al., 2020), our method further reduces repetition without impacting the language model quality. We also evaluate other methods for improving generation at training and decoding time, and compare them using various metrics aimed at control for better text generation output., Comment: accepted to EACL 2021

The lack of interoperability among IoT platforms has led to a fragmented environment, where the users and society as a whole suffer from lock-ins, lack of privacy, and reduced functionality. This paper presents SOFIE, a solution for federating the existing IoT platforms in an open and secure manner using Distributed Ledger Technologies (DLTs) and without requiring modifications to the IoT platforms, and describes how SOFIE is used to enable two complex real life pilots: food supply chain tracking from field to fork and electricity distribution grid balancing with guided electrical vehicle (EV) charging. SOFIE's main contribution is to provide interoperability between IoT systems while also enabling new functionality and business models., Comment: 5 pages. European Conference on Networking and Communications 2019 (EuCNC 2019)

We consider the problem of night-time atmosphere monitoring at the locations of the Yakutsk EAS array and the TAIGA observatory for the annual October-April period of observations at these facilities. It is shown that the use of data from instruments aboard Terra, Aqua, Suomi-NPP and NOAA-20 satellites, received by the ground stations of the Altai State University, Russia, and processed to Level 2 (retrieval of geophysical parameters of the atmosphere), gives the possibility of the near-real-time monitoring observations of the cloud cover structure and the temperature profiles at night with a spatial resolution and a frequency sufficient for meteorological correction of the detector readings., Comment: 7 pages, 6 figures, 26th Extended European Cosmic Ray Symposium

Recent balloon-borne and satellite experiments have established new features in the behavior of the spectra of cosmic rays. An analysis of all the data showed that hardening of most abundant primary cosmic ray nuclei spectra with increasing rigidity is observed in $>200$ GV region. At the same time, rigidity dependencies of secondary cosmic rays are distinctly different. The AMS-02 data show that above 200 GV the secondary cosmic rays Li, Be, B harden more than the primary He, C, O. In this paper we discuss a new scenario that self-consistently describes these new features of the cosmic ray spectra. We demonstrate that the measured by the AMS-02 changes in the slope of the cosmic ray spectra caused by the transition from the contribution of multiple distant Galactic sources, including the nuclear interactions of the particles accelerated by these sources with an interstellar medium during their wandering in the Galaxy, to the contribution of mainly local ones. We also found that the spectral universality is observed at rigidity $R> 10^5$ GV., Comment: 8 pages, 4 figures, 26th Extended European Cosmic Ray Symposium

We consider the problem of the cosmic ray spectrum formation assuming that cosmic rays are produced by Galactic sources. The anomalous diffusion equation proposed in our recent papers is used to describe cosmic ray propagation in the interstellar medium. We show that in the framework of this approach and with generation spectrum exponent $\gamma=2.85$ it is possible to reproduce locally observed basic features of cosmic rays in the energy region of $10^{10}\div 10^{20}$ eV: difference between spectral exponents of protons and other nuclei, mass composition variation, `knee' problem, flattening of the primary spectrum at $E \geq 10^{18}\div 10^{19}$ eV. The crucial model predictions for the mass composition behaviour in the ultra-high energy region are discussed., Comment: 7 pages, 4 figures, 24th European Cosmic Ray Symposium

We present the results of new calculations of the energy spectra of cosmic ray electrons, positrons and also positron fraction under assumption that both electrons and positrons are generated by the same Galactic sources, which accelerate particles with same power-law injection spectral index $p$. The value of the injection index $p\approx 2.85$ retrieved in our works from the analysis of the observed CR spectra has been used. The propagation of particles through the highly non-homogeneous interstellar medium has been described by the anomalous diffusion model. We show that proposed approach allows the self-consistent description of the recent AMS-02 data. In contrast to the conclusion made by AMS-02 collaboration about the different origin of the high-energy positrons and electrons, our results demonstrate that the differing behavior of spectral indices of electrons and positrons with energy can be described under the assumption that both positrons and electrons have common Galactic sources. Our prediction (Lagutin et al. Bull. Russian Academy of Sciences. Physics, 2013, Vol. 77, No. 11, p. 1312) that the $e^{+}$ to total $e^{-} + e^{+}$ ratio reaches a constant value for E $\gg 200$ GeV is confirmed., Comment: 8 pages, 5 figures, 24th European Cosmic Ray Symposium

The paper is a script of a lecture given at the ISAPP-Baikal summer school in 2018. The lecture gives an overview of the Tunka Advanced Instrument for cosmic rays and Gamma Astronomy (TAIGA) facility including historical introduction, description of existing and future setups, and outreach and open data activities., Comment: Lectures given at the ISAPP-Baikal Summer School 2018: Exploring the Universe through multiple messengers, 12-21 July 2018, Bol'shie Koty, Russia

Lateral distributions of electrons in air showers initiated by photons of ultra high energies ($10^{18}-10^{22}$ eV) obtained on the basis of numerical solution of adjoint cascade equations are presented. An extended analysis has been made considering separately the Landau-Pomeranchuk-Migdal (LPM) effect and the interaction of photons and electrons with the geomagnetic field (GMF) with respect to the scaling formalism for lateral distributions. It is shown that one-parametric scaling description of the lateral distribution of electrons remains valid up to the highest energies considering the LPM and GMF effects, that allow effective primary particle type discrimination using the surface detectors data of largest ground-based air shower arrays., Comment: Presented at 26th Extended European Cosmic Ray Symposium 2018 (Barnaul-Belokurikha, Russia). Submitted to Journal of Physics: Conference Series

New analysis of lateral distributions (LD) of electrons, muons and charged particles in extensive air showers generated by $10^{15}-10^{19}$ eV cosmic rays has been made with respect to the scaling formalism for LD and air shower universality paradigm. It is found that lateral distributions of electrons and muons, when considered separately, are well described by one-parametric scaling functions, while for the charged particles mixture distributions the scaling description is not accurate in radial distance range where electrons and muons give a comparable contribution to the local particle densities. The use of scaling formalism enables enhancing the electron/muon separation capabilities and, when combined with theoretically motivated air shower universality concept, provides robust mass composition estimates. The proposed approach could be implemented for the present and future (multi-) hybrid air shower observations, especially in realizing the potential of Auger and Telescope Array observatories upgrades, as well as for re-analysis and cross-calibration of the data collected from different air shower arrays in a broad primary energy range., Comment: Presented at 26th Extended European Cosmic Ray Symposium (http://ecrs18.asu.ru). Submitted to Journal of Physics Conference Series

Content-centric networking (CCN) introduces a paradigm shift from a host centric to an information centric communication model for future Internet architectures. It supports the retrieval of a particular content regardless of the physical location of the content. Content caching and content delivery networks are the most popular approaches to deal with the inherent issues of content delivery on the Internet that are caused by its design. Moreover, intermittently connected mobile environments or disruptive networks present a significant challenge to CCN deployment. In this paper, we consider the possibility of using mobile users in improving the efficiency of content delivery. Mobile users are producing a significant fraction of the total Internet traffic, and modern mobile devices have enough storage to cache the downloaded content that may interest other mobile users for a short period too. We present an analytical model of the CCN framework that integrates a delay tolerant networking architecture into the native CCN, and we present large-scale simulation results. Caching on mobile devices can improve the content retrieval time by more than 50%, while the fraction of the requests that are delivered from other mobile devices can be more than 75% in many cases., Comment: IEEE Access Journal

Information-Centric Networking (ICN) introduces a paradigm shift from a host centric communication model for Future Internet architectures. It supports the retrieval of a particular content regardless of the physical location of the content. Emergency network in a disaster scenario or disruptive network presents a significant challenge to the ICN deployment. In this paper, we present a Content dIstribution and retrieval framework in disaster netwOrks for public pRotection (CIDOR) which exploits the design principle of the native CCN architecture in the native Delay Tolerant Networking (DTN) architecture. We prove the feasibility and investigate the performance of our proposed solution using extensive simulation with different classes of the DTN routing strategies in different mobility scenarios. The simulation result shows that CIDOR can reduce the content retrieval time up to 50% while the response ratio is close to 100%., Comment: International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob)

The Constrained Application Protocol (CoAP) and its extensions, such as observe and group communication, offer the potential for developing novel IoT applications. However, a full-fledged CoAP-based application requires delay-tolerant communication and support for multicast: since these properties cannot be easily provided by existing IP networks, developers cannot take full advantage of CoAP, preferring to use HTTP instead. In this demo we show how proxying CoAP traffic over an ICN network can unleash the full potential of CoAP, simultaneously shifting overhead and complexity from the (constrained) endpoints to the network.