Homogenized behavior of architectured materials can thus be used in large structural computations, hence enabling the dissemination of architectured materials in the industry. As a matter of fact, one engineering challenge is to predict the effective properties of such materials computational homogenization using finite element analysis is a powerful tool to do so. The present chapter aims at providing such models, in the case of mechanical properties. Indicators of geometrical and mechanical percolation, especially relevant for connected microstructures, are proposed and estimated using 3D image analysis.Īrchitectured materials involve geometrically engineered distributions of microstructural phases at a scale comparable to the scale of the component, thus calling for new models in order to determine the effective properties of materials. This is due to a different percolation behaviour of the hard phase in the materials, which is investigated in the last section of the article. In particular, material A is twice as stiff as material B. Numerical predictions of the effective properties using simulations on a large number of subdomains extracted from the samples with periodic boundary conditions are in satisfactory agreement with available experimental results. The samples of material A are found to be representative, whereas at least twice as large sample volumes would be necessary to predict the properties of material B with a precision of 5%. A numerical and statistical computational homogenization methodology first proposed for random models of microstructures in is extended here to the case of real microstructures in order to estimate the size of representative volume elements (RVE) for both materials. Direct simulations on the entire samples show that KUBC and SUBC provide strongly different apparent properties, which rises the question of the representativity of the samples. For that purpose, finite element simulations based on explicit meshing of the microstructures are performed on six samples of the materials, with different boundary conditions: kinematic uniform (KUBC), stress uniform (SUBC) and periodic boundary conditions. Education should be used to solve this conflict, as it is one of the most important tools at our disposal.Three-dimensional confocal images of two materials A and B from food industry made of two constituents with highly contrasted properties, having the same volume fraction but different morphologies, are used to estimate their effective elastic and thermal properties. The main problem facing relations between Chisinau and Tiraspol is a lack of efficient communication. The discourse is aggressive and hateful, which is not acceptable in the twenty-first century and which violates existing international standards. In many cases, textbooks are based on Soviet historiography, and Western neighbors are treated as enemies. History education reflects the official discourse and focuses on Transnistrian interests. The separatist region of Transnistria, established after 1991, controls its own educational system, including curricula and textbooks. The post-Soviet states with ongoing internal or external conflicts have even greater difficulties in the process of statehood construction. Moreover, each political involvement in the process of changing history curricula and textbooks in the past decades has provoked vehement debate and protest in Moldovan society. The Republic of Moldova is among those states where the country’s identity discourse and history education are closely related to each other. In the new post-Soviet political context, history education and history textbooks have played an important role throughout the processes of state-building identity formation. Post-Soviet political developments, regime dynamics, democratic or (in some cases) authoritarian transformations, civil society, conflicts and identity issues constitute the subjects most often under research. The demise of the USSR and subsequent developments in the former Soviet republics have continued to attract the attention of social scientists for two and a half decades.
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