查看更多>>摘要：This article shows an Ito-Wentzell type formula adapted to Young integral. Weapply this formula to study differential equations driven by a-Holder paths with alpha is an element of(1/2, 1]. We obtain a formula for the composition and the inverse of solution maps associated with a Young differential equation. Also, we prove a Leibniz rule for interchanging derivative and the Young integral, and a substitution formula for Young integrals. We also study the Cauchy problemfor first-order semilinear differential equations driven by a Holder path via the Method of Characteristics. We also prove a version of the structure theorem of characteristics in the Young context. We conclude by showing the explicit solution of a transport equation perturbed by the H-fractional Brownian motion with Hurst parameter 1/2 < H <= 1. (C) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：The Lee-Huang-Yang(LHY) correction to the mean field dynamics, originated from quantum fluctuations, can suppress the collapse and create stable localized modes in two and three dimensional systems. Binary quantum droplets(QDs) are studied in free space by introducing the effect of Lee-Huang-Yang correction to the mean field dynamics. Three types of binary QDs are studied, one is belonging to the ground state and the other two are belonging to excited states. In the ground state, the shape change of QDs is demonstrated. Two types of semi-vortex (SV) quantumdroplets, one with a bell-shaped fundamental component and the otherwith the ring-shaped fundamental component, are found in the semi-vortex system. Their characteristics depends on their total norms N, embedded vorticity(topological charge) S and coupling constant g. A noticeable finding is that the SV QDs can be stable up to S= 8. It is found that the size of the quantum droplets depends only on the total norms N, while the inner radii of the vortex component depend only on the embedded vorticity S. The relative share of the total norms of each component with different S is also demonstrated. The stability boundary of the SV QDs are given by the long time evolution. It is found that the SV QDs with the bell-shaped fundamental component are easier to table in relevant small N, while the SV QDs with ring-shaped fundamental components need more large total norms to be stabled. It should be noted that there is a bistable area for these two kinds of SV QDs in the parameter plane of (4p/g, N). The binary vortex quantum droplets, with different embedded vorticity S in each component, are also discussed. (C) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：In this paper, a Chikungunya dynamical model with virus mutation and transovarial transmission is developed, which incorporates the effect of seasonal temperature changes on disease transmission through time-dependent parameters. Firstly, the threshold parameter (Rm) that determines the persistence and ex -0 tinction of mosquito populations is given, and then the disease reproduction number R-0 is defined. Sec-ondly, it is proved that if (R-0(m)) > 1 and R-0 < 1, the disease disappears; if (R-0(m)) > 1 and R-0 > 1, then 0 0 Chikungunya with mutants and non-mutants will persist simultaneously. Finally, a case study is carried out with the data in Kerala, India, where the virus mutation causes the outbreak of Chikungunya. Data on newly confirmed human cases in the state between 2007 and 2010 is fitted and the theoretical results obtained in the previous section are validated. In addition, the effects of seasonal temperature change, virus mutation and transovarial transmission on the prevalence of the disease are studied by numerical simulations from different aspects. 2020 MSC: 34K13; 37N25; 92D30.(C) 2022 Elsevier Ltd. All rights reserved.
De Santis, DuilioGuarcello, ClaudioSpagnolo, BernardoCarollo, Angelo...
5页
查看更多>>摘要：The generation of travelling sine-Gordon breathers is achieved through the nonlinear supratransmission effect in a magnetically driven long Josephson junction, in the presence of losses, a current bias, and a thermal noise source. We demonstrate how to exclusively induce breather modes by means of controlled magnetic pulses. A nonmonotonic behavior of the breather-only generation probability is observed as a function of the noise intensity. An experimental protocol providing evidence of the Josephson breather's existence is proposed.(c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Pneumococcal pneumonia is a contagious, possibly fatal bacterial lung infection that can strike at any time and in any place. It can land you in the hospital and possibly put your life in jeopardy in severe situations. Pneumonia can range from a minor illness to a major or life-threatening infection and it can even be fatal. Therefore, it is of great importance to conceptualize the transmission phenomena of this dangerous infection and to provide control interventions. Here, an epidemic model to conceptualize the transmission phenomena of pneumococcal pneumonia with vaccination and treatment factors is structured. The equilibria of the model are inspected and the reproduction parameter (indicated by Script capital R-0) is determined. Stability results for the equilibria of the system have been proved. The reproduction parameters of the scheme are analyzed numerically with the variation of various input parameters. Moreover, adequate conditions for the uniqueness and existence of the solution to the hypothesized problem of pneumococcal pneumonia infection have been proved. Different simulations of the recommended pneumococcal pneumonia model are performed by changing the input factors to study the complicated dynamics of pneumococcal pneumonia infection with the influence of different input parameters of the system. This article discusses the system's dynamic behavior in order to develop effective infection control policies. Important changes have been observed when the order of the fractional derivative is decreased. This study recommended different factors for the reduction of pneumococcal pneumonia to the policymakers in the community.(c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Many fractional-order grey models are proposed and discussed for electric power generation data analysis, which are helpful in enterprise production and policy scheduling. Considering that time-delay is a universal phenomenon in real life and engineering application, a new and comprehensive conformable fractional grey time-delay model is established by extending classical grey models with the forms of conformable fractional derivative, conformable fractional accumulation and delay parameters. Considering delay data is always unknown, Lagrange interpolation is used to estimate the time-delay data. Compared with linear estimation, high order Lagrange interpolation will provide more detail information in the fitting stage. Furthermore, the optimal and modified models are also disused for predicting the future power generation by the tested data in this paper. The errors between the simulated and real data were analyzed and predicted by autoregression model, which is good at revealing the inner trend for historical residuals. The accuracies of modeling and forecasting can be improved by the optimization algorithm and autoregression error estimation in this paper. The results show the optimal and modified models could be widely used in forecasting electrical time series data, which has high effectiveness and flexibility. The novel model could enrich the connotation of parameters and the physical significance of the traditional fractional grey model. (c) 2022 Elsevier Ltd. All rights reserved.
Fernandes, Leonardo H. S.Silva, Jose W. L.de Araujo, Fernando H. A.
10页
查看更多>>摘要：This paper examines the Brazilian inflation indexes dynamics using the multifractal detrended fluctuations analysis (MF-DFA) and the multifractal detrended cross-correlation analysis (MF-DCCA). We find that the Brazilian inflation indexes (alpha(0)> 0.5) and the pairs of Brazilian Inflation indexes (Delta alpha> 0.5) display a persistentmultifractal behaviour, high complexity and skewsymmetries. Also, we propose a novel multifractal risk measure (MR) considering the multifractal cross-correlation measure (MRCC). The higher MR and MRCC values indicate the more complex and persistent analyzed phenomenon. In contrast, the lowest MR value indicates less complexity and less persistence. Froma Macroeconophysics perspective, our findings clarify that the dynamics of Brazilian inflation indexes and the pairs of Brazilian inflation indexes genuinely have a robust inertial component that makes inflation last for a long time. (C) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：The world has been undergoing a global economic recession for almost two years because of the health crisis stemming from the outbreak and its effects have still continued so far. Especially, COVID-19 reduced consumer spending due to social isolation, lockdown and travel restrictions in 2020. As a result of this, with social and economic life coming to a standstill, oil prices plummeted. With the ongoing uncertainty concerning the COVID-19 pandemic, it has been of great importance for all economic agents to predict crude oil prices. The objective of this paper is to improve a model in order to make more accurate predictions for crude oil price movements. The performance of this model is assessed in terms of some significant criteria comparing our model with its counterparts as well as artificial neural networks (ANNs) and support vector machine (SVM) methods. As for these criteria, root mean square error (RMSE) and mean absolute error (MAE) results show that this model outperforms other models in forecasting crude oil prices. Further, the simulation results for 2021 show that the daily crude oil price forecasts are almost close to the real oil prices. Oil price forecasting has become more and more important for economic agents in COVID-19 period. A consistent model is required to cope with the movements in crude oil prices. A novel method combining fuzzy time series and the greatest integer function is developed. The results show that our model outperforms other counterparts or ANN and SVM methods. We capture non-linearity and volatility in crude oil prices. (c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：To improve the electrical characteristics of an analog indium-gallium-zinc oxide (IGZO) memristor, two kinds of IGZO memristive device with different electrode materials were fabricated, and their electrical characteristics and switching mechanisms were analyzed. It was confirmed that the endurance and retention characteristics of the IGZO memristive device were improved, which was explained by the analysis of operation mechanism. Analog IGZO memristive devices operate through interfacial switching based on the Schottky barrier modulation resulting from the generation and recombination of oxygen vacancies, but the devices with silicon electrode perform analog switching based on conductive filaments through the forming process. The retention time of both devices was measured and estimated with exponential decay functions, and the pulse-induced learning characteristics were also verified. The electrical and synaptic characteristics were considered in the modified national institute of standards and technology (MNIST) database pattern recognition test, and the effects of retention and linearity of weight-update on the recognition rate were analyzed.
Guyo, G. A.Pavlov, A. N.Pitsik, E. N.Frolov, N. S....
5页
查看更多>>摘要：Multiresolution wavelet analysis with thorough processing of decomposition coefficients using a set of cumulants is proposed as a way to improve the characterization of complex dynamics based on experimental data. The application of this approach for quantification the effects of aging in the responses of the electrical activity of the brain to fine motor tasks (clenching the fist) is considered. It is shown that young and elderly adults have significant differences in reactions to this type of movements carried out by the dominant and nondominant hand. The characterization of inter-group distinctions using the skewness and kurtosis of the probability distribution of the wavelet decomposition coefficients outperforms the diagnostics of age-related differences based on standard deviation of this distribution. (C) 2022 Elsevier Ltd. All rights reserved.
NSTL
Elsevier