bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on signal modulation based on machine learning intelligent algorithm and computer automatic identification
Authors: Li Zixi 
Published: December 2021

Abstract
In the process of communication, modulation signal recognition and classification are an important part of non-cooperative communication. Automatic modulation recognition technology of communication signals based on feature extraction and pattern recognition is a key research object in the radio field. The use of neural network can achieve automatic recognition of a variety of modulation signals and achieve good results. In this method, the received signal is preprocessed to obtain the complex baseband signal including in-phase component and orthogonal component. As the data set of the input convolution neural network model, the signal further optimizes the traditional method of manual extraction of expert features for communication signal recognition, which has great limitations and low accuracy under low signal-to-noise ratio, and the simulation results are verified. The results show that the proposed method has stronger feature representation ability and competitiveness in automatic modulation recognition, and is helpful to promote the application of deep learning in the field of automatic modulation recognition.
Modelling the water droplet motion on a leaf surface
Authors: Oqielat Moa’ath N. 
Published: December 2021

Abstract
The main object of the research given in this paper is modelling the water droplet movements on the leaf surface which is an important factor in realising how pesticide, nutrient or water engrossed through the surface. Therefore, a physical model based on mathematics proposed here for producing a realistic trajectory of droplet traversing a leaf surface. A vital feature of our methodology is to build the leaf surface using a recently developed method, by the author, so-called a hybrid CloughTocher cubic polynomial interpolation (CT-CPI) method. The leaf surface consisted of a mesh of triangles over which the hybrid CT-CPI method is build from 3D real life data gathered using a laser scanner. The droplet motion in our model affected by friction, resistance and gravity forces. The model verified using Matlab programming; the outcomes are promising and seem to capture reality well.
Evaluation of the vacuum infusion process objectives at the early stages of computer simulation
Authors: Huang J-P , Zhilyaev I , Snezhina N , Shevtsov S 
Published: December 2021

Abstract
Increasing the quality and reliable reproducibility of large-size composite structures molding using the vacuum infusion method, which is gaining popularity in various industries, is achieved in practice through numerous tests by try and errors that require significant costs and time. The purpose of these tests is to determine the layout of the ports for the resin injection and vacuum supply, as well as the temperature regime that ensures the absence of isolated non-impregnated zones, the minimum porosity and the required reinforcement volume fraction in the composite. The proposed approach removes the simplifying assumptions used in commercial software for modeling the process, which reduce the accuracy of reconstruction of its dynamics and the sensitivity to the formation of unrepairable defects such as dry spots. It involves multiphysics modeling of resin filling in a porous preform by describing the resin front dynamics by the phase field equation, pressure distribution in an unsaturated porous medium by the Richards equation, the evolution of the degree of cure by the convection / diffusion / thermokinetics equation, and thermal processes by the heat transfer equation using modified models of viscosity, the diffusion coefficient of the degree of cure, the boundary condition for the vacuum port. To reduce the finite element computation time of the investigated variants of the process, which is necessary for its computer optimization, the predictive partial sub-criteria were used, which give a reliable prediction before the beginning of the resin gel and solidification. Due to this, a gain in computation time is 30-50% with a significant prediction accuracy of quality objectives and the presence of possible defects.
Validation of a spatial-time concentration gradients estimation by the superposition of sphere sources diffusion fields using the finite element method
Authors: Nartsissov Y.R. 
Published: December 2021

Abstract
A convectional reaction-diffusion is the main process causing a stable distribution of nutrients in biological objects. Indeed, the boundary problems for PDE are always used to describe this phenomenon. The spatial structure of biological objects is usually complex and non-uniform. Therefore, the creation of a digital phantom where gradients will be estimated becomes an especial procedure taking both a computational time and the resources. Recently, a simplified method of time dependent concentration gradient evaluation has been introduced. It represents the final spatial-time distribution as a superposition of the sphere sources diffusion fields. Using such an approximation, one can avoid preliminary reconstruction of digital mech-objects simulating a biological structure. In the present study the introduced approach is validated using the finite element method (FEM). It was shown that the exactness of coincidence is determined by the reciprocal distance of the sources and the scale of the considered area. The symmetry of a mutual boundary position plays an essential part in a validation conformity. A sphere sources formed field differs from the finite element method estimation on 7% under the most appropriate conditions. Other possible applications of the introduced approach to concentration gradient modelling in biological objects are discussed.
Energy analysis of Duffing oscillators with quadratic damping: exact solutions
Authors: Rakaric Z , Kovacic I 
Published: December 2021

Abstract
Oscillators with a Duffing-type restoring force and quadratic damping are dealt with in this paper. Four characteristic cases of this restoring force are analysed: hardening, softening, bistable and a pure cubic one. Their energy-displacement relationships are considered, and the corresponding closed-form exact solutions are obtained in terms of the incomplete Gamma function, which represent new results. Such results provide insight into damped dynamics of the class of system, including finding the phase trajectories as well as the comparison between these cases from the viewpoint of the energy loss per cycle.
A novel algorithm of the digital nervous tissue phantom creation based on 3D Voronoi diagram application
Authors: Nartsissov Y.R. 
Published: December 2021

Abstract
The essential part of mathematical modelling of nutrients convectional reaction-diffusion is creation of a digital phantom of considered biological object. This process becomes an especial problem which needs to be solved before numerical calculations of the concentration gradients will be done. There are two principal ways to get the solution in this case. The first approach is the reconstruction of a digital phantom on the base of the experimental data directly. The second one is the creation of a virtual object according to the experimental evidence and the known principals de novo. The main advantage of the created phantom is a high adaptability to modelling demands and a physical problem formulation. In the present study a new algorithm of a digital phantom creation has been established. The principles of the claimed procedures are demonstrated by the example of a nervous tissue. Initially, one needs to create N 3D objects according to Voronoi diagrams. Each object has 144 edges and 69 boundaries on average. Having chosen M rear objects, a long 3D structure mimicking neurons axons is created according to a loft procedure from the start boundaries to the end ones. Then, the set of Boolean operations has been applied to form continuous smooth objects. The remain (N-(M+s)) objects are combined into several whole bodies using the loft procedures between the closet neighbours. The final structure has a good conformity with a nervous tissue architecture. Furthermore, the obtained phantom is correct to the mesh application and further numerical calculations.
Features of the Multi-Criteria Optimization Mathematical Model of the Thermal and Electrical Loads Distribution at a Combined Heat and Power Plant with a Mixed Equipment Composition
Authors: Arakelyan E K , Andryushin A V , Mezin S V , Kosoy A A 
Published: December 2021

Abstract
The features of the mathematical model of multi-criteria optimization of the distribution of current thermal and electrical loads at a combined heat and power plant with a mixed composition of equipment based on traditional heating units and a heating CCGT are considered. The previously proposed mathematical apparatus for solving the problem of multi-criteria optimization at a thermal power plant is analyzed. It is shown that with a mixed composition of equipment, along with the criteria of efficiency and environmental friendliness, it is also necessary to take into account the factors of reliability and mobility (maneuverability). The substantiation of the choice of reliability and mobility criteria for optimizing the operation modes of a thermal power plant is given. Approaches to solving the multi-criteria task are considered. The description of the features of the algorithm for solving the optimization problem is given in relation to thermal power plants with a mixed composition of equipment, including heating turbines of the T type and PGU.
Digital twin of the management process of field service teams of an electric grid company
Authors: Kinzhalieva A R , Protalinskiy O M , Khanova A A , Bondareva I O 
Published: December 2021

Abstract
Modern electric grid companies are focused on minimum economically feasible costs and are aimed at improving the efficiency of financial and economic activities through the rational use of resources. The digital twin structure is proposed for the management of field service teams in the event of accidents and technological failures in an electric grid company. The digital twin includes an agent model, a system dynamics model, a geographic information system component, and modules with experiments. The description of the simulation model of management of field service teams in the event of accidents and technological failures is formalized, the input and output information on the model components is highlighted, the information is structured, and the scheme of the system dynamics model is created. Experiment designs for the digital twin of the management of field service teams in the event of accidents and technological failures in order to determine the best reliability and cost indicators are developed. The developed approach can be used to create digital twins of the management process of field service teams in the event of accidents and technological failures for various electric grid companies by selecting the parameters of simulation models according to the statistical reports by electric grid companies and connecting the appropriate GIS modules.
The effect of privacy concerns, risk, control, and trust on individuals’ decisions to share personal information: A game theory-based approach
Authors: Dimodugno M , Hallman S , Plaisent M , Bernard P 
Published: December 2021

AbstractThe rapid developments and innovations in technology have created unlimited opportunities for private and public organizations to collect, store and analyze the large and complex information about users and their online activities. Data mining, data publishing, and sharing sensitive data with third parties help organizations improve the quality of their products and services and raise significant individuals’ privacy concerns. Privacy of personal information remains subject to considerable controversy. The problem is that big data analytics methods allow user’s data to be unlawfully generated, stored, and processed by leaving users with little to no control over their personal information. This quantitative correlational study measures the effect of privacy concerns, risk, control, and trust on individuals’ decisions to share personal information in the context of big data analysis. The key research question aimed to examine the relationship among the variables of perceived privacy concerns, perceived privacy risk, perceived privacy control, and trust. Drawing on Game Theory, the study explores all the game players’ actions, strategies, and payoffs. Correlation analysis was used to test these variables based on the research model with 418 internet users of e-services in the United States. The overall correlation analysis showed that the variables were significantly related. Recommendations for future studies are to explore e-commerce, e-government, and social networking separately, and data should be collected in different regions where many factors can affect the privacy concerns of the individuals.
Understanding the outbreak of COVID-19 in Ecuador
Authors: Tene Talia , Guevara Marco , Svozilík Jiří , Gomez Cristian Vacacela 
Published: December 2021

Abstract
In this study is presented a mathematical approach that can be used to estimate the variability of the growth rate coefficient (λ), the total number of cases, and the midpoint of maximum infection due to the COVID-19 pandemic. The different parameters are quantified using one-year data set reported for Ecuador (from March 2020 to February 2021) and the (discrete or differential) logistic model. In particular, the results evidence that the most critical months of the pandemic in Ecuador were March and April 2020. In the following months, the outbreak continues with low growth rate values but in a variable way, which can be attributed to state health policies and the social behavior of the population. The estimated number of confirmed cases is around 409 K agrees with the data reported at the end of May 2021, validating the proposed mathematical approach.
The correlation analysis of the daily Covid-19 new cases data series in Albania
Authors: Gjana Agron , Kovaçi Sandër 
Published: December 2021

Abstract
We analyzed herein the new covid-19 daily positive cases recorded in Albania. We observed that the distribution of the daily new cases is non-stationary and usually has a power law behavior in the low incidence zone, and a bell curve for the remaining part of the incidence interval. We qualified this finding as the indicator intensive dynamics and as proof that up now, the heard immunity has not been reached. By parallelizing the preferential attachment mechanisms responsible for a power law distribution in the social graphs elsewhere, we explain the low daily incidence distribution as result of the imprudent gatherings of peoples. Additionally, the bell-shaped distribution observed for the high daily new cases is agued as outcome of the competition between illness advances and restriction measures. The distribution is acceptably smooth, meaning that the management has been accommodated appropriately. This behavior is observed also for two neighbor countries Greece and Italy respectively, but was not observed for Turkey, Serbia, and North Macedonia. Next, we used the multifractal analysis to conclude about the features related with heterogeneity of the data. We have identified the local presence self-organization behavior in some separate time intervals. Formally and empirically we have identified that the full set of the data contain two regimes finalized already, followed by a third one which started in July 2021.
The influence of accidental physical contacts between individuals on viral infection
Authors: Derevich I V , Panova A A 
Published: December 2021

Abstract
The paper is devoted to the results of numerical modelling of non-stationary effects during the spread of a viral infection in a small group of individuals. We are considering the case of the spread of a viral infection by airborne droplets. Two consecutive stages of infection of the body are considered. At the first stage, virions enter the lungs and as a result of viremia are transported to the affected organs. In the second stage, the virions actively replicate in the affected organs. Random movement of individuals in the group changes the local concentration of virions near the selected individual. The random level of virion concentration may be greater than a certain critical value after which the infection of the selected individual will go into an irreversible stage. The main purpose of our work is to illustrate qualitatively new effects that occur in nonlinear systems in a random environment.
Mathematical Model Considering Effect of COVID-19 Contact-Confirming Application (COCOA) and “GoTo Travel Campaign”
Authors: Maehashi Ryota , Nagaoka Rian , Nigoshi Yuka , Hayashi Yuga , Moriguchi Ryuhei , Kakimoto Yohei , Toyotani Jun , Hara Kazuyuki , Takahashi Hirotaka , Omae Yuto 
Published: December 2021

Abstract
In the end of 2019, the emergence of COVID-19 was reported and confirmed for the first time, and it triggered an international pandemic. In Japan, the strong tendency to spread of infection is still continuing. The Japanese Government has been raised two concepts to overcome this difficulty. One is the thorough measures to control of the spread of infection and the other is the economic recovery. The government has carried out the corresponding two policies: the use of COVID-19 Contact-Confirming Application (COCOA) and the application of “GoTo Travel Campaign”. We focus on these two policies and study an ideal situation, which enables us to balance more economic recovery and control of the spread of infection. To pursue this goal, we propose a mathematical model to estimate these policies’s effects and conduct simulations of 28 scenarios. In addition, we analyze each result of the simulation and investigate characteristics of each situation. As a result, we clearly find that it required that not only the increasing the using rate of COCOA but also a positive change of people’s behaviors and awareness.
Does the Zero Carry Essential Information for Artificial Neural Network learning to simulate the contaminant transport in Urban Areas?
Authors: Berendt-Marchel M. , Wawrzynczak A. 
Published: December 2021

Abstract
The release of hazardous materials in urbanized areas is a considerable threat to human health and the environment. Therefore, it is vital to detect the contamination source quickly to limit the damage. In systems localizing the contamination source based on the measured concentrations, the dispersion models are used to compare the simulated and registered point concentrations. These models are run tens of thousands of times to find their parameters, giving the model output’s best fit to the registration. Artificial Neural Networks (ANN) can replace in localization systems the dispersion models, but first, they need to be trained on a large, diverse set of data. However, providing an ANN with a fully informative training data set leads to some computational challenges. For example, a single simulation of airborne toxin dispersion in an urban area might contain over 90% of zero concentration in the positions of the sensors. This leads to the situation when the ANN target includes a few percent positive values and many zeros. As a result, the neural network focuses on the more significant part of the set - zeros, leading to the non-adaptation of the neural network to the studied problem. Furthermore, considering the zero value of concentration in the training data set, we have to face many questions: how to include zero, scale a given interval to hide the zero in the set, and include zero values at all; or limit their number? This paper will try to answer the above questions and investigate to what extend zero carries essential information for the ANN in the contamination dispersion simulation in urban areas. For this purpose, as a testing domain, the center of London is used as in the DAPPLE experiment. Training data is generated by the Quick Urban & Industrial Complex (QUIC) Dispersion Modeling System.
The effects of gravitational potential on chemical reaction rates
Authors: Lecca Paola 
Published: December 2021

Abstract
This study aims to answer through a mathematical model and its numerical simulation the question whether the kinetic rate constants of chemical reactions are influenced by the strength of gravitational field. In order to calculate the effects of gravity on the kinetic rate constants, the model of kinetic rate constants derived from collision theory is amended by introducing the mass and length corrections provided by general relativity. Numerical simulations of the model show that the rate constant is higher where the gravitational field is more intense.
Geometry, Coordinatization and Cardinality of the Rational Numbers from Physical Perspective
Authors: Ghosh Kaushik 
Published: December 2021

Abstract
In this article, we will first discuss the completeness of real numbers in the context of an alternate definition of the straight line as a geometric continuum. According to this definition, points are not regarded as the basic constituents of a line segment and a line segment is considered to be a fundamental geometric object. This definition is in particular suitable to coordinatize different points on the straight line preserving the order properties of real numbers. Geometrically fundamental nature of line segments are required in physical theories like the string theory. We will construct a new topology suitable for this alternate definition of the straight line as a geometric continuum. We will discuss the cardinality of rational numbers in the later half of the article. We will first discuss what we do in an actual process of counting and define functions well-defined on the set of all positive integers. We will follow an alternate approach that depends on the Hausdorff topology of real numbers to demonstrate that the set of positive rationals can have a greater cardinality than the set of positive integers. This approach is more consistent with an actual act of counting. We will illustrate this aspect further using well-behaved functionals of convergent functions defined on the finite dimensional Cartezian products of the set of positive integers and non-negative integers. These are similar to the partition functions in statistical physics. This article indicates that the axiom of choice can be a better technique to prove theorems that use second-countability. This is important for the metrization theorems and physics of spacetime.
Higher-order Darboux transformations for two-dimensional Dirac systems with diagonal matrix potential
Authors: Schulze-Halberg A 
Published: December 2021

Abstract
We construct the explicit form of higher-order Darboux transformations for the two-dimensional Dirac equation with diagonal matrix potential. The matrix potential entries can depend arbitrarily on the two variables. Our construction is based on results for coupled Korteweg-de Vries equations [27].