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On Temporal Behaviour of Solutions in Thermoelasticity of Porous Micropolar Bodies

Abstract

We consider a porous thermoelastic body, including voidage time derivative among the independent constitutive variables. For the initial boundary value problem of such materials, we analyze the temporal behaviour of the solutions. To this aim we use the Cesaro means for the components of energy and prove the asymptotic equipartition in mean of the kinetic and strain energies.

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Temporal species turnover and plant community changes across different habitats in the Lake Engure Nature Park, Latvia

. Sci. Sect. B, 65 (5/6) 138-145. Kollmann, J., Rasmussen, K. (2012). Succession of a degraded bog in NE Denmark over 164 years - monitoring one of the earliest restoration eksperiments. Tuexenia, 32, 67-85. Krieger, A., Porembski, S., Barthlott, W. (2003). Temporal dynamics of an ephemeral plant community: Species turnover in seasonal rock pools on Ivorian inselbergs. Plant Ecol., 167, 283-292. Kuiters, A. T. (2013). Diversity-stability relationships in plant communities of contrasting habitats. J. Veg. Sci., 24, 453

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On continuous dependence for the mixed problem of microstretch bodies

Abstract

We do a qualitative study on the mixed initial-boundary value problem in the elastodynamic theory of microstretch bodies. After we trans- form this problem in a temporally evolutionary equation on a Hilbert space, we will use some results from the theory of semigroups of linear operators in order to prove the continuous dependence of the solutions upon initial data and supply terms.

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Error Analysis and Model Adaptivity for Flows in Gas Networks

Abstract

In the simulation and optimization of natural gas flow in a pipeline network, a hierarchy of models is used that employs different formulations of the Euler equations. While the optimization is performed on piecewise linear models, the flow simulation is based on the one to three dimensional Euler equations including the temperature distributions. To decide which model class in the hierarchy is adequate to achieve a desired accuracy, this paper presents an error and perturbation analysis for a two level model hierarchy including the isothermal Euler equations in semilinear form and the stationary Euler equations in purely algebraic form. The focus of the work is on the effect of data uncertainty, discretization, and rounding errors in the numerical simulation of these models and their interaction. Two simple discretization schemes for the semilinear model are compared with respect to their conditioning and temporal stepsizes are determined for which a well-conditioned problem is obtained. The results are based on new componentwise relative condition numbers for the solution of nonlinear systems of equations. More- over, the model error between the semilinear and the algebraic model is computed, the maximum pipeline length is determined for which the algebraic model can be used safely, and a condition is derived for which the isothermal model is adequate.

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Solute transport in aquifers with evolving scale heterogeneity

References [1] Attinger, S., Dentz, M., H. Kinzelbach, and W. Kinzelbach (1999), Temporal behavior of a solute cloud in a chemically heterogeneous porous medium, J. Fluid Mech., 386, 77-104. [2] Bellin, A., M. Pannone, A. Fiori, and A. Rinaldo (1996), On transport in porous formations characterized by heterogeneity of evolving scales, Water Resour. Res., 32, 3485-3496. [3] Cintoli, S., S. P. Neuman, and V. Di Federico (2005), Generating and scaling fractional Brownian motion on finite domains, Geophys. Res. Lett

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An adaptive stepsize algorithm for the numerical solving of initial-value problems

.D., Computational Methods in Ordinary Differential Equations , Wiley, 1973. [12] Marin, M., Florea O., On temporal behavior of solutions in Thermoelasticity of porous micropolar bodies , An. St. Univ. Oidius Constanta vol. 22 , issue 1, (2014), 169-188. [13] Marin, M., Sharma, K., Reflection and transmission of waves from imperfect boundary between two heat conducting micropolar thermoelastic solids , An. St. Univ. Oidius Constanta vol. 22 , issue 2, (2014), 151-175. [14] MATLAB The Language of Technical Computing , MathWorks, 2004. [15] Philips, G

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Some remarks on a fractional integro-differential inclusion with boundary conditions

), 758-772. [11] Filippov, A.F., Classical solutions of differential equations with multivalued right hand side , SIAM J. Control 5 (1967), 609-621. [12] Karthikeyan, K., Trujillo, J.J., Existence and uniqueness results for fractional integro-differential equations with boundary value conditions , Commun Nonlinear Sci. Numer. Simulat. 17 (2012), 4037-4043. [13] Kilbas, A., Srivastava, H.M., Trujillo, J.J., Theory and Applications of Fractional Differential Equations , Elsevier, Amsterdam, 2006. [14] Marin, M., Florea, O., On temporal

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A Spectral Approach to Peak Velocity Estimation of Pipe Flows from Noisy Image Sequences

References [BGPS15] E. Bodnariuc, A. Gurung, S. Petra, and C. Schnőrr, Adaptive Dictionary-Based Spatio-temporal Flow Estimation for Echo PIV, Proc. EMMCVPR, Lecture Notes in Computer Science, vol. 8932, Springer, 2015, pp. 378-391. [BMR00] E. G. Birgin, J. M. Martinez, and M. Raydan, Nonmonotone Spectral Projected Gradient Methods on Convex Sets, SIAM Journal on Optimization 10 (2000), no. 4, 1196-1211. [BPPS16] E. Bodnariuc, S. Petra, C. Poelma, and C. Schnőrr, Parametric Dictionary-Based Velocimetry for Echo

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Nonuniform exponential stability for evolution families on the real line

-autonomous equations in Banach spaces , J. Dynam. Differential Equations 3 (1998), 489-510. [9] Levitan, B.M., Zhikov, V.V., Almost Periodic Functions and Differential Equations , Cambridge Univ. Press, Cambridge, 1982. [10] Marin, M., Florea, O., On temporal behaviour of solutions in Thermoelasticity of porous micropolar bodies , An. Sti. Univ. Ovidius Constanţa, Vol. 22 , issue 1, (2014) 169-188. [11] Massera, J.L., Schäffer, J.J., Linear Differential Equations and Function Spaces , Academic Press, New York, 1966. [12] Van Minh, N., Räbiger, F

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Consistency issues in PDF methods

, A joint velocity-concentration PDF method for tracer ow in heterogeneous porous media, Water Resour. Res., 46 (2010) W12522. [9] R. W. Bilger, The Structure of Diffusion Flames, Combust. Sci. Tech. 13 (1976) 155-170. [10] S. Attinger, M. Dentz, H. Kinzelbach, W. Kinzelbach, Temporal behavior of a solute cloud in a chemically heterogeneous porous medium, J. Fluid Mech. 386 (1999) 77-104. [11] N. Suciu, C. Vamos, J. Vanderborght, H. Hardelauf, H. Vereecken, Numerical investigations on ergodicity of solute transport in

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