The paper deals with a modeling of the ongoing epidemic caused by Coronavirus disease 2019 (COVID-19) on the closed territory of the Republic of Croatia. Using the official public information on the number of confirmed infected, recovered and deceased individuals, the modified SEIR compartmental model is developed to describe the underlying dynamics of the epidemic. Fitted modified SEIR model provides the prediction of the disease progression in the near future, considering strict control interventions by means of social distancing and quarantine for infected and at-risk individuals introduced at the beginning of COVID-19 spread on February, 25 th by Croatian Ministry of Health. Assuming the accuracy of provided data and satisfactory representativeness of the model used, the basic reproduction number is derived. Obtained results portray potential positive developments and justify the stringent precautionary measures introduced by the Ministry of Health.

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The human exposure assessment to wireless communications systems including the fifth generation (5G) mobile systems is related to determining the specific absorption rate (SAR) or the absorbed power density (APD). The assessment of both quantities requires the use of various numerical techniques, including moments method (MoM). As the use of MoM results in a fully populated system matrix, a tremendous computational cost is incurred, both in terms of matrix fill time and memory allocation, as the matrix size is directly related to frequency of the problem. This paper investigates the applicability of numerical integration at frequencies related to 5G. The novelty of this work is related to the comprehensive set of tests of various combination of source and observation triangles using the developed unit cube test. A number of convergence tests were performed to investigate the effects of the increasing frequency and the discretization scheme on the numerical solution, as well as to determine how to curb the computational requirements by the proficient use of numerical integration. The results show that in the lower GHz range, lower integration orders could be used, resulting in the decrease of matrix fill time without loss of solution accuracy.

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This paper examines the effect of electromagnetic induction on the electrophysiology of a single cortex neuronthrough two different modes associated with the nature of the external neuronal stimulus. By using the recently extended induction-based variant of the well-known and biologically plausible Hodgkin-Huxley neuron model, bifurcation analysis is performed. Electromagnetic induction caused by magnetic flux is captured using a polynomial approximation of a memristor embedded into the neuron model. In order to determine true influence of the variability of ion channels conductivity, the stochastic sensitivity analysis is performed post hoc. Additionally, numerical simulations are enriched with uncertainty quantification, observing values of ion channels conductivity as random variables. The aim of the study is to computationally determine the sensitivity of the action potential dynamics with respect to the changes in conductivity of each ion channel so that the future experimental procedures, most often medical treatments, may be adapted to different individuals in various environmental conditions.