Mikhail Alexeevich Kharitonov

Extreme flooding of the floodplains of large lowland rivers poses a danger to the population due to the vastness of the flooded areas. This requires the organization of safe evacuation in conditions of a shortage of temporary and transport resources due to significant differences in the moments of flooding of different spatial parts. We consider the case of a shortage of evacuation vehicles, in which the safe evacuation of the entire population to permanent evacuation points is impossible. Therefore, the evacuation is divided into two stages with the organization of temporary evacuation points on evacuation routes. Our goal is to develop a method for analyzing the minimum resource requirement for the safe evacuation of the population of floodplain territories based on a mathematical model of flood dynamics and minimizing the number of vehicles on a set of safe evacuation schedules. The core of the approach is a numerical hydrodynamic model in shallow water approximation. Modeling the hydrological regime of a real water body requires a multi-layer geoinformation model of the territory with layers of relief, channel structure, and social infrastructure. High-performance computing is performed on GPUs using CUDA. The optimization problem is a variant of the resource investment problem of scheduling theory with deadlines for completing work and is solved on the basis of a heuristic algorithm. We use the results of numerical simulation of floods for the Northern part of the Volga-Akhtuba floodplain to plot the dependence of the minimum number of vehicles that ensure the safe evacuation of the population. The minimum transport resources depend on the water discharge in the Volga river, the start of the evacuation, and the localization of temporary evacuation points. The developed algorithm constructs a set of safe evacuation schedules for the minimum allowable number of vehicles in various flood scenarios. The population evacuation schedules constructed for the Volga-Akhtuba floodplain can be used in practice for various vast river valleys.

The subject of our study is the tendency to reduce the floodplain area of regulated rivers and its impact on the degradation of the socio-environmental systems in the floodplain. The aim of the work is to create a new approach to the analysis and forecasting of the multidimensional degradation processes of floodplain territories under the influence of natural and technogenic factors. This approach uses methods of hydrodynamic and geoinformation modeling, statistical analysis of observational data and results of high-performance computational experiments. The basis of our approach is the dynamics model of the complex structure of the floodplain. This structure combines the characteristics of the frequency ranges of flooding and the socio-environmental features of various sites (cadastral data of land use). Modeling of the hydrological regime is based on numerical shallow water models. The regression model of the technogenic dynamics of the riverbed allowed us to calculate corrections to the parameters of real floods that imitate the effect of this factor. This made it possible to use digital maps of the modern topography for hydrodynamic modeling and the construction of floods maps for past and future decades. The technological basis of our study is a set of algorithms and software, consisting of three modules. The data module includes, first of all, the cadastres of the territory of the Volga-Akhtuba floodplain (VAF, this floodplain is the interfluve of the Volga and Akhtuba rivers for the last 400 km before flowing into the Caspian Sea), satellite and natural observation data, spatial distributions of parameters of geoinformation and hydrodynamic models. The second module provides the construction of a multilayer digital model of the floodplain area, digital maps of floods and their aggregated characteristics. The third module calculates a complex territorial structure, criteria for the state of the environmental and socio-economic system (ESES) and a forecast of its changes. We have shown that the degradation of the ESES of the northern part of the VAF is caused by the negative dynamics of the hydrological structure of its territory, due to the technogenic influence the hydroelectric power station on the Volga riverbed. This dynamic manifests itself in a decrease in the stable flooded area and an increase in the unflooded and unstable flooded areas. An important result is the forecast of the complex territorial structure and criteria for the state of the interfluve until 2050.

The article describes the methods and algorithms of numerical optimization for the hierarchical structures, described by hierarchical graphs with structurally dependent objective functions that can be represented as superpositions of elementary objective functions, specified at their vertices. On their basis, the authors built and implemented formal models and algorithms for analytical and numerical optimization by symmetric hierarchical structures of the production subsystems of enterprises with structurally dependent production functions of the Leontief type.

The purpose of the paper is studying the optimality properties of local artificial channel systems of floodplain territories. It proposes the method to construct the topological structure and cross-sectional area of artificial channels, which maximize the total weighted area of the flooded territory. To state adequate formulation and solution of the control problem, the authors made an adaptive zoning floodplain territory digital model for the areas with an insignificant effect of interband flooding at small and medium floods. The optimal capacity of small channels was detected using a multi-step recursive dynamic programming method. It is presented the numerical results obtained by computer hydrodynamic simulations of flood dynamics and geoinformation modeling of the spatially distributed relief parameters of several FAV northen sections.

SHS Web of Conferences, open access proceedings in Humanities and Social Sciences

Contents IJPAM: Volume 107, No. 4 (2016)

This paper suggests a constrained optimization model for the operating core of an organization. Structurally, the core consists of the basic technological module and several modules of support facilities. The production function of the operating core is represented through the superposition of Leontief production functions corresponding to each of the modules. We reduce the optimization problem to a linear programming problem with a parameter describing the operational structure of the core. In addition, we develop a certain algorithm for automatic construction of the basic equations for each value of the parameter. Finally, the optimization problem is solved numerically for a wide range of the model variables and parameters. The proposed model may serve for designing generalized control mechanisms for an organizational system on a large horizon.