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151.
152.
Michal Martinek Sumita Swar Veronika Zajícová Lukáš Voleský Lenka Blažková Jana Müllerová Martin Stuchlík Michal Řezanka Ivan Stibor 《Chemical Papers》2017,71(12):2403-2415
Polypyrrole-coated polyethylene terephthalate is very attractive for various applications as electrically conductive fiber. This paper investigates the importance of polyester pre-treatment on the quality of the polypyrrole coating and its conductivity efficiency. The results showed nucleophilic pre-treatments by Grignard reagents resulting in the significantly higher surface quality and strongest adhesion of the polypyrrole coating to the polyester fibers compared to the other published methods. Moreover, several Grignard reagents were used for altering the hydrophobicity and morphology of the surface. 相似文献
153.
Lukáš Poul 《Central European Journal of Mathematics》2008,6(3):422-438
We consider the full Navier-Stokes-Fourier system of equations on an unbounded domain with prescribed nonvanishing boundary
conditions for the density and temperature at infinity. The topic of this article continues author’s previous works on existence
of the Navier-Stokes-Fourier system on nonsmooth domains. The procedure deeply relies on the techniques developed by Feireisl
and others in the series of works on compressible, viscous and heat conducting fluids. 相似文献
154.
In this article we present a simple and elegant algebraic proof of Pascal’s hexagon theorem which requires only knowledge
of basics on conic sections without theory of projective transformations. Also, we provide an efficient algorithm for finding
an equation of the conic containing five given points and a criterion for verification whether a set of points is a subset
of the conic. 相似文献
155.
Tomáš Kroupa 《Algebra Universalis》2018,79(4):86
Probability maps are additive and normalised maps taking values in the unit interval of a lattice ordered Abelian group. They appear in theory of affine representations and they are also a semantic counterpart of Hájek’s probability logic. In this paper we obtain a correspondence between probability maps and positive operators of certain Riesz spaces, which extends the well-known representation theorem of real-valued MV-algebraic states by positive linear functionals. When the codomain algebra contains all continuous functions, the set of all probability maps is convex, and we prove that its extreme points coincide with homomorphisms. We also show that probability maps can be viewed as a collection of states indexed by maximal ideals of a codomain algebra, and we characterise this collection in special cases. 相似文献
156.
We show that every frame can be essentially embedded in a Boolean frame, and that this embedding is the maximal essential extension of the frame in the sense that it factors uniquely through any other essential extension. This extension can be realized as the embedding \(L \rightarrow \mathcal {N}(L) \rightarrow \mathcal {B}\mathcal {N}(L)\), where \(L \rightarrow \mathcal {N}(L)\) is the familiar embedding of L into its congruence frame \(\mathcal {N}(L)\), and \(\mathcal {N}(L) \rightarrow \mathcal {B}\mathcal {N}(L)\) is the Booleanization of \(\mathcal {N}(L)\). Finally, we show that for subfit frames the extension can also be realized as the embedding \(L \rightarrow {{\mathrm{S}}}_\mathfrak {c}(L)\) of L into its complete Boolean algebra \({{\mathrm{S}}}_\mathfrak {c}(L)\) of sublocales which are joins of closed sublocales. 相似文献
157.
Uroš Kuzman 《Journal of Geometric Analysis》2010,20(1):168-176
We study the deformation space of an embedded J-holomorphic disc D in an almost complex surface (X,J). Every such J is shown to be equivalent to a small deformation of a certain model structure J
β
along D, where β
:
D→ℂ is a complex valued function whose modulus |β| is a biholomorphic invariant. Furthermore, we find a nonlinear invertible operator mapping the space of all small J-holomorphic deformations of the given J-holomorphic disc onto the space of small holomorphic deformations of the standard disc in ℂ2. 相似文献
158.
We extract the abstract core of finite homomorphism dualities using the techniques of Heyting algebras and (combinatorial)
categories. 相似文献
159.
Michal Hnatič Georgii Kalagov Tomáš Lučivjanský 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(11):269
Motivated by the ubiquity of turbulent flows in realistic conditions, effects of turbulent advection on two models of classical non-linear systems are investigated. In particular, we analyze model A (according to the Hohenberg–Halperin classification [P.C. Hohenberg, B.I. Halperin, Rev. Mod. Phys. 49, 435 (1977)]) of a non-conserved order parameter and a model of the direct bond percolation process. Having two paradigmatic representatives of distinct stochastic dynamics, our aim is to elucidate to what extent velocity fluctuations affect their scaling behavior. The main emphasis is put on an interplay between anisotropy and compressibility of the velocity flow on their respective scaling regimes. Velocity fluctuations are generated by means of the Kraichnan rapid-change model, in which the anisotropy is due to a distinguished spatial direction n and a correlator of the velocity field obeys the Gaussian distribution law with prescribed statistical properties. As the main theoretical tool, the field-theoretic perturbative renormalization group is adopted. Actual calculations are performed in the leading (one-loop) approximation. Having obtained infrared stable asymptotic regimes, we have found four possible candidates for macroscopically observable behavior for each model. In contrast to the isotropic case, anisotropy brings about enhancement of non-linearities and non-trivial regimes are proved to be more stable. 相似文献
160.
Miloje S. Radenković Miloš S. Stanković Srdjan S. Stanković 《Journal of Optimization Theory and Applications》2018,179(3):1008-1024
In this paper, we propose a stochastic approximation algorithm for optimization of functions based on an adaptive extremum seeking method. The essence of this method is to approximate the gradient direction by introduction of a probing sequence, that is added to approximations and subsequently demodulated using an adaptive gain. Assuming that the probing and the demodulation signals are martingale difference sequences with adaptive diminishing gains, it is proved that the approximations converge almost surely to the optimizing value, under mild constraints on the measurement disturbance, and without assuming a priori boundedness of the approximation sequence. The measurement disturbance can contain a stochastic component, as well as a mean-square bounded deterministic component. The stochastic component can be nonstationary colored noise or a state-dependent random sequence. 相似文献