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Purpose. A goal of the work is development of 3D numerical model for a territorial risk assessment in a case of a terrorist attack with usage of a chemical agent. Methodology. To describe the process of chemical agent dispersion in the atmosphere, emitted in a case of a terrorist attack, the equation of mass transfer of an admixture in atmospheric air is used. The equation takes into account a velocity of the wind flow, atmospheric diffusion, an intensity of chemical agent emission, a buildings presence near a place of a chemically hazardous substance release. For numerical integration of the modeling equation, a finite difference method is used. A feature of the developed numerical model is possibility of a territorial risk assessment in a case of a terrorist attack under different weather conditions and a buildings presence. For calculation of wind flow velocity field in a case of building presence 3D equation for potential of velocity is used. Findings. The specialized numerical model and software package which can be used for a territorial risk assessment, both in a case of terrorist attacks with usage of chemical agents, and in a case of extreme situations at chemically hazardous facilities and transport are developed. The method can be implemented on small and medium-powered computers, which allows it to be widely used for solving this class of problems. The results of a computational experiment are presented that allow estimating possibilities of the proposed method for assessing a territorial risk in a case of a terrorist attack with usage of chemical agent. Originality. An effective method of a territorial risk assessment in a case of a terrorist attack with usage of a chemically hazardous substance is proposed. The method can be used to assess a territorial risk in an urban environment, which allows to obtain adequate data about possible affected areas. The method is based on numerical integration of the fundamental mass transfer equation, which expresses the law of conservation of mass in a liquid medium. Practical value. The proposed method for a territorial risk assessment in a case of a terrorist attack with usage of a chemical agent can be used to calculate the affected areas near administrative buildings, centers and other socially significant facilities.

Purpose.The purpose of the paper is: (1) the definition of perspectives development of Ukrainian railway tourism on the narrow gauge lines of Zakarpattia; 2) technical condition analysis of Borzhava narrow gauge railway for the project to restore the effective functioning of mountain railways track, width 750 mm in the Carpathian region, with the possibility of their accession to the distributed travel network; 3) the study of the modern state and tendencies of development of tourist industry of Ukraine and the passenger economy of national railways; 4) clarification of the role and place of the railway tourism in the transportation system. Methodology. The expert group has carried out field inspections and field investigations of facilities track facilities and passenger infrastructure, rolling stock and ancillary industries involved in the functioning narrow-gauge railway. It was estimated the overall technical condition of the railway track and engineering structures section of narrow-gauge Railways in the Carpathian region. Findings. In the framework of on-site examinations of the expert group found that the objects of tracks, passenger and freight infrastructure, rolling stock and ancillary industries involved in the operation of narrow-gauge Railways are in poor condition and require significant updates and major repairs. But the routes of passenger trains remain fit for participation in the project of development of railway tourism of Ukraine Originality. For the first time the state of the narrow-gauge railway for further implementation of the project on the development of rail tourism in Ukraine was realized. The analysis of foreign experience of organization of railway tourism has been carried out. The modern state and tendencies of development of tourist industry of Ukraine was studied, the factors of competitiveness of rail transport for providing tourist transport in Ukraine were identified and systematized.Practical value. The recovery and effective functioning of mountain railways with a width of 750 mm in the Carpathian region will give an impetus to the tourism development, engineering, construction and energy. At the same time, these actions will allow us to finally implement a scientifically-based effective flood control measures that will protect the population from natural environmental disasters.

Purpose. The aim of the research is to build a model of the generalzed logistic mapping and assessment of the possibilities of its use for the formation of the mathematical description, as well as operational forecasts of parameters of complex dynamic processes described by the time series. Methodology. The research results are obtained on the basis of mathematical modeling and simulation of nonlinear systems using the tools of chaotic dynamics. Findings. A model of the generalized logistic mapping, which is used to interpret the characteristics of dynamic processes was proposed. We consider some examples of representations of processes based on enhanced logistic mapping varying the values of model parameters. The procedures of modeling and interpretation of the data on the investigated processes, represented by the time series, as well as the operational forecasting of parameters using the generalized model of logistic mapping were proposed. Originality. The paper proposes an improved mathematical model, generalized logistic mapping, designed for the study of nonlinear discrete dynamic processes. Practical value. The carried out research using the generalized logistic mapping of railway transport processes, in particular, according to assessment of the parameters of traffic volumes, indicate the great potential of its application in practice for solving problems of analysis, modeling and forecasting complex nonlinear discrete dynamical processes. The proposed model can be used, taking into account the conditions of uncertainty, irregularity, the manifestations of the chaotic nature of the technical, economic and other processes, including the railway ones.

In the article the use of method of T. Demark for construction of the operative forecast of the basic indicators of activity of railway transport enterprises is offered.