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The finite element quasi‐static analysis of elastoplastic systems is studied by making use of a generalized variable approach for the spatial discretization and a generalized mid‐point rule for the time integration. Both the classical form of the constitutive law and the convex analysis formulation are presented. The relation between the mid‐point time integration and the extremal path theory is discussed. Extremal properties for the finite‐step solution are formulated.

Science of systems requires a specific and constructive mathematical model and language, which describe jointly such systemic categories as adaptation, self‐organization, complexity, evolution, and bring the applied tools for building a system model for each specific object of a diverse nature. This formalism should be connected directly with a world of information and computer applications of systemic model, developed for a particular object. The considered information systems theory (IST) is aimed at building a bridge between the mathematical systemic formalism and information technologies to develop a constructive systemic model of revealing information regularities and specific information code for each object.

To fulfill this goal and the considered systems' definition, the IST joins two main concepts: unified information description of interacted flows, initiated by the sources of different nature, with common information language and systems modeling methodology, applied to distinct interdisciplinary objects; general system's information formalism for building the model, which allows expressing mathematically the system's regularities and main systemic mechanisms.

The formalism of informational macrodynamics (IMD), based of the minimax variational principle, reveals the system model's main layers: microlevel stochastics, macrolevel dynamics, hierarchical dynamic network (IN) of information structures, its minimal logic, and optimal code of communication language, generated by the IN hierarchy, dynamics, and geometry. The system's complex dynamics originate information geometry and evolution with the functional information mechanisms of ordering, cooperation, mutation, stability, diversity, adaptation, self‐organization, and the double helix's genetic code.

The developed IMD's theoretical computer‐based methodology and the software has been applied to such areas as technology, communications, computer science, intelligent processes, biology, economy, management, and other nonphysical and physical subjects.

The IMD's macrodynamics of uncertainties connect randomness and regularities, stochastic and determinism, reversibility and irreversibility, symmetry and asymmetry, stability and instability, structurization and stochastization, order and disorder, as a result of micro‐macrolevel's interactions for an open system, when the external environment can change the model's structure.

Fat‐tailed distributions have been found in many financial and economic variables ranging from forecasting returns on financial assets to modeling recovery distributions in bankruptcies. They have also been found in numerous insurance applications such as catastrophic insurance claims and in value‐at‐risk measures employed by risk managers. Financial applications include:

A theory of knowledge shows that all four systems of nature are recursive combinatorial‐hamiltonian self‐programmed flow‐wave systems that can be deduced from the usual Conservation Law promoted to the Axiom of Science.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

The potential advantage of extreme value theory in modeling management phenomena is the central theme of this paper. The statistics of extremes have played only a very limited role in management studies despite the disproportionate emphasis on unusual events in the world of managers. An overview of this theory and related statistical models is presented, and illustrative empirical examples provided.

A typology of basic affective and cognitive orientations is developed within a generic cultural socio-cognitive trait theory of a “plural affect agency” (the emotional organisation).

Affective personality is defined in terms of a set of affect traits. These are defined in terms of epistemically independent bipolar affect types, which in turn coalesce into a set of mindset types that can be related to the classical four temperaments.

Different affect types are supposed to differently regulate the three stages of emotion management. Affect types and cognitive types provide mutual contexts, and foster reciprocal affect and cognitive orientations.

The theory provides guidance for analysis of cultural differentiation within social systems (societies/organisations), with reference to identification, elaboration and execution of “emotion knowledge” and “cognitive knowledge”.

Understanding interdependencies between cognition and emotion regulation is a prerequisite of managerial intelligence and strategic cultural intelligence, which is in demand for interaction and integration processes across social systems.

From the framework model linking emotion expression and emotion regulation with cognition analysis, a typology arises allowing ex-ante expectation of typical patterns of behaviour.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

The purpose of this paper is to assess the Gurson yield criterion for porous ductile metals.

A finite element procedure is used within a purely kinematical multi‐scale constitutive modelling framework to determine estimates of extremal overall yield surfaces. The RVEs analysed consist of an elastic‐perfectly plastic von Mises type matrix under plane strain conditions containing a single centered circular hole. Macroscopic yield surface estimates are obtained under three different RVE kinematical assumptions: linear boundary displacements (an upper bound); periodic boundary displacement fluctuations (corresponding to periodically perforated media); and, minimum constraint or uniform boundary traction (a lower bound).

The Gurson criterion predictions fall within the bounds obtained under relatively high void ratios – when the bounds lie farther apart. Under lower void ratios, when the bounds lie close together, the Gurson predictions of yield strength lie slightly above the computed upper bounds in regions of intermediate to high stress triaxiality. A modification to the original Gurson yield function is proposed that can capture the computed estimates under the three RVE kinematical constraints considered.

Assesses the accuracy of the Gurson criterion by means of a fully computational multi‐scale approach to constitutive modelling. Provides an alternative criterion for porous plastic media which encompasses the common microscopic kinematical constraints adopted in this context.