The asymptotic method

The article is devoted to the shape optimization of shell structures in Comsol Multiphysics using three gradient-based methods: IPOPT (Interior Point OPTimizer), SNOPT (Sparse Nonlinear OPTimizer) and MMA or GCMMA (the Method of Moving Asymptotes). Two types of complex shapes, such as right helicoid and developable helicoid are taken for the computational experiment.

11p viamancio 04-06-2024 1 0   Download

Ebook "Introduction to physical oceanography" begins with the basic equations of motion in integral form and covers such essential topics as geostropic flow, barotropic and baroclinic ocean circulations, vorticity, and the astronomical tides. Among the many appendices is one on the method of Matched Asymptotic Expansions as applied to the Gulf Stream the most modern and systematic way of looking at boundary layer problems. Problems are included at the end of each chapter.

354p duongthandue0501 28-02-2024 1 1   Download

The result show that taking into account the coupling between the deformation of the porous space and the capillary effects can radically modify the prediction of the temperature influence on the capillary curve.

12p vijeff 30-11-2023 10 4   Download

In this paper, we present the establishment the vibration equation for the study of nonlinear beam effects. A illustrative example allows us to derive equations und use nonlinear vibration for calculating vibration of beams.

19p vijeff 30-11-2023 6 3   Download

In this paper, using the asymptotic a priori estimate method, we prove the existence of pullback attractors for a nonautonomous semilinear strongly degenerate parabolic equation, without restriction on the growth order of the polynomial type non-linearity and with a suitable exponential growth of the external force. The obtained results improve some recent ones for the non-autonomous reaction–diffusion equations.

9p nhanchienthien 25-07-2023 4 3   Download

In the paper, a hierarchical fuzzy sliding-mode controller (HFSMC) designing method is proposed. This method provides a simple way to achieve asymptotical stability and remove the chattering signal for a class of SIMO under-actuated systems with fuzzy control rules. This class of under-actuated systems is made from several subsystems.

9p vidoctorstrange 06-05-2023 9 3   Download

In this paper, an approach method to improve secrecy cooperation transmissions using combined signals is investigated in which data and jamming signals are combined at a source node based on power allocation strategy. The secrecy system performances are evaluated using asymptotic secrecy outage probabilities of end-to-end achievable secrecy rates over flat and block Rayleigh fading channels.

9p vidoctorstrange 06-05-2023 7 2   Download

The purpose of this paper is to combine the Bregman distance with the shrinking projection method to introduce a new hybrid iteration process for a generalized mixed equilibrium problem and a Bregman totally quasi-asymptotically nonexpansive mapping.

17p viellenkullman 16-05-2022 11 1   Download

This model relaxes the assumption, crucial to slab methods, that the stresses are uniformly distributed through the thickness of each material layer. Thus, our model is able to predict the through-thickness velocity and stress distributions.

10p guernsey 28-12-2021 9 0   Download

The asymptotic form of solution is a specific solution of difference equations. It represents the rate of convergence of solution to equilibrium point of difference equations. In this paper, we investigate asymptotic form of a class of nonlinear difference equations. By asymptotic method, we show the existence of a solution of a class of difference equations converging to zero as n " 3 , and to determine its asymptotic behavior

3p chauchaungayxua11 23-03-2021 9 1   Download

In this work, a sliding mode control (SMC) method and a composite learning SMC (CLSMC) method are proposed to solve the synchronization problem of chaotic fractional-order neural networks (FONNs). A sliding mode surface and an adaptive law are constructed to update parameter estimation. The SMC ensures that the synchronization error asymptotically tends to zero under a strict permanent excitation (PE) condition. To reduce its rigor, online recording data together with instantaneous data is used to define a prediction error about the uncertain parameter.

10p dayhoctainha 10-09-2020 22 0   Download

In this paper, by combining the shrinking projection method with a modified inertial Siteration process, we introduce a new inertial hybrid iteration for two asymptotically Gnonexpansive mappings and a new inertial hybrid iteration for two G-nonexpansive mappings in Hilbert spaces with graphs. We establish a sufficient condition for the closedness and convexity of the set of fixed points of asymptotically G-nonexpansive mappings in Hilbert spaces with graphs.

13p caygaocaolon6 22-07-2020 13 2   Download

In hybrid structures, material layers of different mechanical properties are integrated to increase bearing capacity. When the difference in mechanical properties or thickness of the material layers is very large, debonding usually occurs along the interface between the two layers. This study uses a homogenization procedure combined with asymptotic algorithm applied on weaker/thinner materials to determine the interface stiffnesses for such structures. All the material layers and the interface are assumed to be linear elastic.

12p kequaidan6 11-07-2020 12 1   Download

This paper derives a semi-analytical solution to determine displacements and stresses in a thick cylindrical shell with variable thickness under uniform pressure based on disk form multilayers. The proposed study partitions the thick cylinder into disk-layer parts based on their thickness of the cylinder.

14p tohitohi 19-05-2020 18 0   Download

A new model is developed in this paper which demonstrates a flexible method for modeling a cash flow stream with a declining growth rate that asymptotically approaches a mature long-term growth rate. This model can be applied when the initial growth rate in cash flows is temporarily larger than the required rate of return.

14p vimadrid2711 18-12-2019 14 2   Download

This is the main result of the paper. We use the method to estimate the region of attraction for the case of the asymptotical stability. We study this technique for the case autonomous systems.

6p vixyliton2711 12-04-2019 39 0   Download

We construct an iteration sequence converging (in the uniform norm in the space of continuous functions) to the solution of the Cauchy problem for a singularly perturbed weakly nonlinear differential equation of an arbitrary order (the weak nonlinearity means the presence of a small parameter in the nonlinear term).

13p nutifooddau 21-01-2019 22 1   Download

This paper intends to study some dynamical properties of a stochastic three-dimensional Lotka–Volterra system. Under some mild assumptions, we first introduce a simple method to show that the model has a global and positive solution almost surely. Secondly, we prove that this model has a stationary distribution. Then we study the global asymptotic stability of the positive solution. Finally, some numerical simulations are introduced to illustrate the theoretical results.

16p danhdanh27 07-01-2019 30 1   Download

The paper develops a general framework to derive the effective properties of quasi-periodic elastic medium. By using the asymptotic expansion method, the solution is expanded to the second order by solving a sequence of minimization problems.

24p danhdanh11 09-01-2019 22 1   Download

We propose an entropy based classification of propositional calculi. Our method can be applied to finite–valued propositional logics and then, extended asymptotically to infinite–valued logics. In this paper we consider a classification depending on the number of truth values of a logic and not on the number of its designated values. Furthermore, we believe that almost the same approach can be useful in classification of finite algebras.

6p danhnguyentuongvi27 19-12-2018 19 1   Download