It is well known that every $x\in (0,1]$ can be expanded to an infinite Lüroth series in the form of $$x=\frac {1}{d_1(x)}+\cdots +\frac {1}{d_1(x)(d_1(x)-1)\cdots d_{n-1}(x)(d_{n-1}(x)-1)d_n(x)}+\cdots , $$ where $d_n(x)\geq 2$ for all $n\geq 1$. In this paper, sets of points with some restrictions on the digits in Lüroth series expansions are considered. Mainly, the Hausdorff dimensions of the Cantor sets $$ F_{\phi }=\{x\in (0,1]\colon d_n(x)\geq \phi (n), \ \forall n\geq 1\} $$are completely determined, where $\phi $ is an integer-valued function defined on $\mathbb N$, and $\phi (n)\to \infty $ as $n\to \infty $.
This paper considers the problem of determining linear relations from data affected by additive noise in the context of the Frisch scheme. The loci of solutions of the Frisch scheme and their properties are first described in the algebraic case. In this context two main problems are analyzed: the evaluation of the maximal number of linear relations compatible with data affected by errors and the determination of the linear relation actually linking the noiseless data. Subsequently the extension of the Frisch scheme to the identification of dynamical systems is considered for both SISO and MIMO cases and the problem of its application to real processes is investigated. For this purpose suitable identification criteria and model parametrizations are described. Finally two classical identification problems are mapped into the Frisch scheme, the blind identification of FIR channels and the identification of AR + noise models. This allows some theoretical and practical extensions.
The aim of this review is to explain the functional significance of mantis peering behaviour from an entomological perspective. First the morphological and optical features of the mantis compound eye that are important for spatial vision are described. The possibility that praying-mantises use binocular retinal disparity (stereopsis) and other alternative visual cues for determining distance in prey capture, are discussed. The primary focus of the review is the importance of peering movements for estimating the distance to stationary objects. Here the following aspects are examined: (1) Direct evidence via object manipulation experiments of absolute distance estimation with the aid of self-induced retinal image motion; (2) the mechanism of absolute distance estimation (with the interaction of visual and proprioceptive information); (3) the range of absolute and relative distance estimation; (4) the influence of target object features on distance estimation; and (5) the relationship between peering behaviour and habitat structures, based on results of studies on three species of mantis., Karl Kral., and Obsahuje seznam literatury
For a finite commutative ring $R$ and a positive integer $k\geqslant 2$, we construct an iteration digraph $G(R, k)$ whose vertex set is $R$ and for which there is a directed edge from $a\in R$ to $b\in R$ if $b=a^k$. Let $R=R_1\oplus \ldots \oplus R_s$, where $s>1$ and $R_i$ is a finite commutative local ring for $i\in \{1, \ldots , s\}$. Let $N$ be a subset of $\{R_1, \dots , R_s\}$ (it is possible that $N$ is the empty set $\emptyset $). We define the fundamental constituents $G_N^*(R, k)$ of $G(R, k)$ induced by the vertices which are of the form $\{(a_1, \dots , a_s)\in R\colon a_i\in {\rm D}(R_i)$ if $R_i\in N$, otherwise $a_i\in {\rm U}(R_i), i=1,\ldots ,s\},$ where U$(R)$ denotes the unit group of $R$ and D$(R)$ denotes the zero-divisor set of $R$. We investigate the structure of $G_N^*(R, k)$ and state some conditions for the trees attached to cycle vertices in distinct fundamental constituents to be isomorphic.
The model for deducing the local value of galactocentric gradient of the velociy dispersion is based on the local distribution of the orbital eccentricity e, the mean orbital radius ω and the velocity perpendicular to the galactic plane. We apply it to samples of the Gliese´s catalogue delimited by stars of F,. Gand K spectral types. We obtain for the galactic radial gradient of velocity disperion: -0,2 kpc-1, a value compatible with the Toomre´s local stability criterion.
The multitalented neuropeptide galanin was first discovered 30 years ago but initially no biologic activity was found. Further research studies discovered the presence of galanin in the brain and some peripheral tissues, and galanin was identified as a modulator of neurotransmission in the central and peripheral nervous system. Over the last decade there were performed very intensive studies of the neuronal actions and also of nonneuronal actions of galanin. Other galanin family peptides have been described, namely galanin, galanin-like peptide, galanin-message associated peptide and alarin. The effect of these peptides is mediated through three galanin receptors subtypes, GalR1, GalR2
and GalR3 belonging to G protein coupled receptors, and signaling via multiple transduction pathways, including inhibition of cyclic AMP/protein kinase A (GalR1, GalR3) and stimulation of phospholipase C (GalR2). This also explains why one specific molecule of galanin can be responsible for different roles in different tissues. The present review summarizes the information currently available on the relationship between the galaninergic system and known pathological states. The research of novel galanin receptor specific agonists and antagonists is also very promising for its future role in pharmacological treatment. The galaninergic system is important target for current and future biomedical research.
Up to present for modelling and analyzing of random phenomenons, some statistical distributions are proposed. This paper considers a new general class of distributions, generated from the logit of the gamma random variable. A special case of this family is the \textit{Gamma-Uniform} distribution. We derive expressions for the four moments, variance, skewness, kurtosis, Shannon and Rényi entropy of this distribution. We also discuss the asymptotic distribution of the extreme order statistics, simulation issues, estimation by method of maximum likelihood and the expected information matrix. We show that the Gamma-Uniform distribution provides great flexibility in modelling for negatively and positively skewed, convex-concave shape and reverse `J' shaped distributions. The usefulness of the new distribution is illustrated through two real data sets by showing that it is more flexible in analysing of the data than of the Beta Generalized-Exponential, Beta-Exponential, Beta-Pareto, Generalized Exponential, Exponential Poisson, Beta Generalized Half-Normal and Generalized Half-Normal distributions. and Na konci článku uvedena podoba jména Narges Montazeri Hedesh