Main pipelines as long linear objects are vulnerable to dangerous natural and man-made influences. One of the technogenic sources is large-scale explosions, which cause a sharp fluctuations of soil and cause serious damage to underground pipelines. When calculating the strength of pipeline systems, it is assumed that the damage occurs mainly due to additional axial stretching. However, the destruction and damage of pipelines can occur during seismic impacts directed perpendicular to the longitudinal axis of the pipeline. To assess the impact of longitudinal and transverse waves on the underground pipeline during seismic action a software-calculation module is developed. It implements a model of dynamic strength analysis, which allows estimating the magnitude of longitudinal and trans-verse seismic loads on the underground pipeline to establish safe parameters of seismic loads and geometric dimensions of the protected object. The final system of equations of motion of N nodes of a discrete system for a single length of the pipeline is presented as a system of 4N equations of the first order. The efforts on the internal nodes are determined by the strain stresses at the displacement of the nodes of the adjacent rods. The efforts on the nodes of the pipe contour are the diffraction interaction of seismic waves in the soil with the pipe. The system of equations is supplemented by the corresponding initial and boundary conditions. The dependences of the inflow of longitudinal and transverse pressure of explosive seismic pressure on the pipeline are established. The dependences of stresses in the pipeline of the diameter, thickness and type of soil are researched.

The present paper provides the dependence of the temperature change on time and the depth of the soil massif based on numerical calculations. Mathematical modelling of the one-dimensional soil temperature field via an algorithm and a PC program is carried out without taking into account the influence of the phase transition of moisture in the soil pores during seasonal freezing and thawing using the finite difference method. The amplitude of fluctuations in the temperature regime is obtained as that decreases with depth from the soil surface. It is established that over time heat spreads from the pipeline to the surface of the soil, and over time more intense heating occurs both near the pipeline and in the body of the soil massif.

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This article aims to study activity and functioning models of clusters, that are an important component of rural development. We present analytical data on their numbers and analyse the main literature on this topic. The main purpose and objectives of the study are to form the concept of the agricultural cluster as a form of cooperation in conditions of competition and to determine its place in regional development policy. We state that the cluster-based policy of regional development (cluster-based policy, CBP) is to coordinate activities in various spheres of economic, political and scientific life. We study the influence of clusters on the competitiveness of the economy and economic development, that allows as to determine the main conditions of cluster development. Particular attention is paid to analyses of one of the successful examples of a fruit cluster created in 2012 in the Masovian Voivodeship (Poland). It was created at the initiative of gardeners and as an attempt to strengthen innovation and competitiveness of the Masovian fruit industry in response to increased competition in the globalization age. The purpose of the cluster is to create an impact on improving cooperation between regional authorities, research units, business organisations and local economies. And, last but not least, to strengthen competitiveness through projects that help in the development and promotion of the fruit sector in the Masovian Voivodeship. We trace the creation of the value chain on the above-mentioned example. The cluster has an open formula, and new members are introduced as the structures expand. To improve quality and innovation in production, logistics and packaging, the Fruit Cluster cooperates with the University of Warsaw, the Institute of Nutrition, the Masovian Agricultural Advisory Centre and the Warsaw University of Technology. From the research that has been carried out, we develop recommendations for implementation of the Polish experience in cluster functioning in Ukraine. We also identify the main reasons that block the successful development of clusters in Ukraine: the imperfection of the legal framework; lack of state support; weakness of existing agrarian clusters due to low level of competition in the domestic market; lack of a single structured information base on existing and potential clusters. We expect that promoting the creation and development of agricultural clusters following the example of Poland will increase the efficiency and competitiveness of agricultural enterprises. And this is an important issue to ensure the development of rural areas in our country.