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The model of information propagation in the heterogeneous system “human—environment” is considered. For the transition from one part of phase space to the other part we use a technique known as joker. The existence of a singularity in the given model is investigated. A computer program has been developed and some of the obtained numerical results are presented. [ABSTRACT FROM AUTHOR]

Franz Reuleaux (1829 - 1905) is a famous mechanical engineer, a Professor of the Berlin Royal Technical Academy. He became widely known as an engineer-scientist, a Professor and industrial consultant, education reformer and leader of the technical elite of Germany. He directed the design and manufacture of over 300 models of simple mechanisms. They were sold to many famous universities for pedagogical and scientific purposes. Today, the most complete set is at Cornell University, College of Engineering. In this article we discuss the history, the modern state and our using the Reuleaux models that survived at St. Petersburg State University for educational purposes. We present description of certain models and our electronic resource with these models. We provide the information of similar electronic resources from other universities. [ABSTRACT FROM AUTHOR]

This paper details findings from the research work targeted at economic communications investigation with agent-based models usage. The agent-based model set was engineered to simulate economic communications. Money in the form of internal and external currencies was introduced into the models to support exchanges in communications. Every model, being based on the general concept, has its own peculiarities in algorithm and input data set since it was engineered to solve the specific problem. Several and different origin data sets were used in experiments: theoretic sets were estimated on the basis of static Leontief's equilibrium equation and the real set was constructed on the basis of statistical data. While simulation experiments, communication process was observed in dynamics, and system macroparameters were estimated. This research approved that combination of an agent-based and mathematical model can cause a synergetic effect. [ABSTRACT FROM AUTHOR]

The paper presents a mathematical model of distribution the discharged heat water from thermal power plant under various operational capacities on the aquatic environment. It was solved by the Navier-Stokes and temperature equations for an incompressible fluid in a stratified medium were based on the splitting method by physical parameters which approximated by the finite volume method. The numerical solution of the equation system was divided into four stages. At the first step it was assumed that the momentum transfer carried out only by convection and diffusion. While the intermediate velocity field was solved by 5-step Runge-Kutta method. At the second stage, the pressure field was solved by found the intermediate velocity field. Whereas Poisson equation for the pressure field was solved by Jacobi method. The third step assumes that the transfer was carried out only by pressure gradient. Finally the fourth step of the temperature equation was also solved as motion equations, with 5-step Runge-Kutta method. The algorithm was parallelized on high-performance computer. The obtained numerical results of three-dimensional stratified turbulent flow were compared with experimental data. What revealed qualitatively and quantitatively approximately the basic laws of hydrothermal processes occurring in the reservoir-cooler. [ABSTRACT FROM AUTHOR]

We propose a three dimensional model for the adhesion and rolling of biological cells on surfaces. We study cells moving in shear flow above a wall to which they can adhere via specific receptor-ligand bonds based on receptors from selectin as well as integrin family. The computational fluid dynamics are governed by the lattice-Boltzmann method. The movement and the deformation of the cells is described by the immersed boundary method. Both methods are fully coupled by implementing a two-way fluid-structure interaction. The adhesion mechanism is modelled by adhesive bonds including stochastic rules for their creation and rupture. We explore a simplified model with dissociation rate independent of the length of the bonds. We demonstrate that this model is able to resemble the mesoscopic properties, such as velocity of rolling cells. [ABSTRACT FROM AUTHOR]

A shortest path based algorithm is proposed in this paper to find splitting lines for touching cells. Firstly, an initial splitting line is obtained through the distance transform of a marker image and the watershed algorithm. Then, the initial splitting line is separated into different line segments if necessary, and the start and end points of these line segments act as the start and end points of shortest path. Finally, the shortest path algorithm is used to find the splitting line between the start and end points, and the final result of touching cells splitting can be formed by the contour of the touching cells and the splitting lines. Experimental results show that the proposed algorithm is efficient for different types of touching cells. [ABSTRACT FROM AUTHOR]

In this paper, a preference relations based on the conflicting bifuzzy set, namely equilibrium linguistic preference relation was introduced. The concept and some relations were studied briefly which emphasis on the new approach to group decision making process. Then, the negation operator, fuzzy arithmetic averaging operator and balancing coefficient were used to aggregate equilibrium linguistic preference information to the ranking and selection of alternatives. Finally, a numerical example is provided to illustrate the proposed approaches. The results show that the method is highly beneficial and offers a new computation technique for problem solving under fuzzy group decision environment. [ABSTRACT FROM AUTHOR]

We discuss how the model of magnetic reconnection in the presence of turbulence proposed in Lazarian & Vishniac 1999 makes the reconnection rate independent either of resistivity or microscopic plasma effects, but determined entirely by the magnetic field line wandering induced by turbulence. We explain that the model accounts for both fast and slow regimes of reconnection and that this property naturally induces flares of reconnection in low beta plasma environments. In addition, we show that the model involves volume reconnection which can convert a substantial part of the energy into energetic particles. It is important that the reconnection induces an efficient acceleration of the first order Fermi type. Finally, we relate the properties of the reconnection with the observed properties of gamma ray bursts and provide evidence supporting the explanation of gamma ray bursts based on energy release via reconnection. [ABSTRACT FROM AUTHOR]

The solubility of CO2 in 1-butylpyridinium bis(trifluoromethylsulfonyl)imide [C4py][Tf2N] ionic liquid has been determined using Magnetic Suspension Balance instrument at 298.15 K and in the pressures up to about 27 bar. A group contribution method, namely UNIFAC has been used to fit the experimental data. The interaction parameters of the model were estimated. The predicted CO2 solubility data by the model shows good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

A robust and reliable computational model of complex human systems dynamics could support advancements in theory and practice for social systems at all levels, from intrapersonal experience to global politics and economics. Models of human interactions have evolved from traditional, Newtonian systems assumptions, which served a variety of practical and theoretical needs of the past. Another class of models has been inspired and informed by models and methods from nonlinear dynamics, chaos, and complexity science. None of the existing models, however, is able to represent the open, high dimension, and nonlinear self-organizing dynamics of social systems. An effective model will represent interactions at multiple levels to generate emergent patterns of social and political life of individuals and groups. Existing models and modeling methods are considered and assessed against characteristic pattern-forming processes in observed and experienced phenomena of human systems. A conceptual model, CDE Model, based on the conditions for self-organizing in human systems, is explored as an alternative to existing models and methods. While the new model overcomes the limitations of previous models, it also provides an explanatory base and foundation for prospective analysis to inform real-time meaning making and action taking in response to complex conditions in the real world. An invitation is extended to readers to engage in developing a computational model that incorporates the assumptions, meta-variables, and relationships of this open, high dimension, and nonlinear conceptual model of the complex dynamics of human systems. [ABSTRACT FROM AUTHOR]

In this contribution we deal with a multi-criteria shape optimization of an induction furnace. We want to find shape parameters of the furnace in such a way, that two different criteria are optimized. Since they cannot be optimized simultaneously, instead of one optimum we find set of partially optimal designs, so called Pareto front. We compare two different approaches to the optimization, one using nonlinear conjugate gradient method and second using variation of genetic algorithm. As can be seen from the numerical results, genetic algorithm seems to be the right choice for this problem. Solution of direct problem (coupled problem consisting of magnetic and heat field) is done using our own code Agros2D. It uses finite elements of higher order leading to fast and accurate solution of relatively complicated coupled problem. It also provides advanced scripting support, allowing us to prepare parametric model of the furnace and simply incorporate various types of optimization algorithms. [ABSTRACT FROM AUTHOR]

Advances in detector techniques, coupled to improved secondary beams at meson factories, have brought about major improvements in the experimental precision of pion and muon rare decay measurements over the last decade. We review recent results, focusing in particular on: π+→π0e+ν (pion beta, πe3, or πβ decay), and π+→e+νγ (radiative pion decay, πe2γ or RPD), as well as the radiative muon decay, μ+→e+ννγ (radiative muon decay, RMD), and their theoretical implications. The PIBETA experiment, with measurements completed at PSI, has brought about an order of magnitude improvement, or better, in the branching ratio precision for these processes. The successor PEN experiment, currently under way at PSI, aims to improve the precision of the π+→e+ν(πe2) decay branching ratio by about an order of magnitude. Each of these results contributes toward a better understanding of the limits on certain particles and interactions not included in the standard model, or toward improving the precision of chiral lagrangian and pion structure parameters. We finally review the near-term prospects for their further improvement. [ABSTRACT FROM AUTHOR]

Retrocausation has been postulated in physical systems and observed in animate systems. The experiments described here extend methods used in human experiments to systems that are inanimate. One random-event generator, the controller-REG, was used to shut off a second REG, the subject-REG, at a random time. The output of the subject-REG was accumulated over several runs, each consisting of hundreds of trials, to look for a change in the randomness of its output bit stream in advance of the subject-REGs shut off. For the first three runs large changes were observed during the last second before shut off, changes of approximately 1 bit in 40 that exceeded odds against chance of 1 million to 1. Variations and later an exact replication of the early results failed to show the changes observed in the first three runs. This failure to replicate is an indication that there is an additional uncontrolled variable that must be taken into account, quite possibly the intention and enthusiasm of the experimenters. That addition leads to the question as to whether the subject-REG was subject to advance influence from its impending shut off, or instead whether its output was in a superposition of different states until the operator observed the results. The observation would then have caused a collapse of the superposition into a fixed state, like the collapse of quantum mechanical wavefunction. In either case, a retroactive influence was clearly in evidence. [ABSTRACT FROM AUTHOR]

Modelling the acoustic scattering and absorption at an area expansion in a flow duct requires the incorporation of the flow-acoustic interaction. One way to quantify the interaction is to study the energy in the incident and the scattered field respectively. If the interaction is strong, energy may be transferred between the acoustic and the main flow field. In particular, shear layers, that may be the result of the flow separation, are unstable to low frequency perturbations such as acoustic waves. The vortex sheet model is an analytical linear acoustic model, developed to study scattering of acoustic waves in duct with sharp edges including the interaction with primarily the separated flows that arise at sharp edges and corners. In the model the flow field at an area expansion in a duct is described as a jet issuing into the larger part of the duct. In this paper, the flow-acoustic interaction is described in terms of energy flow. The linear convective wave equation is solved for a two-dimensional, rectangular flow duct geometry. The resulting modes are classified as “hydrodynamic” and “acoustic” when separating the acoustic energy from the part of the energy arising from the steady flow field. In the downstream duct, the set of modes for this complex flow field are not orthogonal. For small Strouhal numbers, the plane wave and the two hydrodynamic waves are all plane, although propagating with different wave speeds. As the Strouhal numbers increases, the hydrodynamic modes changes to get a shape where the amplitude is concentrated near the vortex sheet. In an intermediate Strouhal number region, the mode shape of the first higher order mode is very similar to the damped hydrodynamic mode. A physical interpretation of this is that we have a strong coupling between the flow field and the acoustic field when the modes are non-orthogonal. Energy concepts for this duct configuration and mean flow profile are introduced. The energy is formulated such that the vortex sheet turns out as a sink for the acoustic field, but a source for the unstable hydrodynamic wave. This model is physical only close to the edge, due to an exponentially growing hydrodynamic mode. In a real flow, non-linearities will limit the growth, but this is not included in the model. [ABSTRACT FROM AUTHOR]

This study presents a model of transverse vibrations in a log with a weak part. The aim is to use this model for the inverse application to find the weak part from measurements of transverse vibrations. More precisely, an optimization procedure based on the square of the difference, between measurements and simulations from the model is formulated. The error in the location of the weak part, caused by noise in measurements, can be reduced by including the spatial derivative of transverse vibrations in the optimization and by choosing an optimal frequency. It is shown that for a weak part with no spatial extension along the log, a weak layer, the optimal frequency is a resonance frequency. The a priori information that there is a weak part makes it possible to use wavelengths much longer than the size of the weak part. [ABSTRACT FROM AUTHOR]

The procedure of recognition can be described as follows: There is a set of complex signals stored in the memory. Choosing one of these signals may be interpreted as generating a hypothesis concerning an “expexted view of the world”. Then the brain compares a signal arising from our senses with the signal chosen from the memory leading to a change of the state of both signals. Furthermore, measurements of that procedure like EEG or MEG are based on the fact that recognition of signals causes a certain loss of excited neurons, i.e. the neurons change their state from “excited” to “nonexcited”. For that reason a statistical model of the recognition process should reflect both—the change of the signals and the loss of excited neurons. A first attempt to explain the process of recognition in terms of quantum statistics was given in [1]. In the present note it is not possible to present this approach in detail. In lieu we will sketch roughly a few of the basic ideas and structures of the proposed model of the recognition process (Section). Further, we introduce the basic spaces and justify the choice of spaces used in this approach. A more elaborate presentation including all proofs will be given in a series of some forthcoming papers [2, 3]. In this series also the procedures of creation of signals from the memory, amplification, accumulation and transformation of input signals, and measurements like EEG and MEG will be treated in detail. [ABSTRACT FROM AUTHOR]