The influence of the steel strip cracking at the wound part of the high pressure compound vessel on the stress, strain and vessel safety has been investigated. An equivalent orthotropic material model with the zero tangential elasticity modulus Et has been utilised to describe this phenomenon. The stress and strain analysis was carried out by means of the problem oriented finite element method (F EM) code PROKOP [2]. The damaged strip packet of thickness 10 mm at any radial position influences negatively the vessel safety. The steel strip cracking near the inner winding radius is more dangerous than the cracking near the outer radius. and Obsahuje seznam literatury
In this paper, we prove that for a given positive continuous t-norm there is a fuzzy metric space in the sense of George and Veeramani, for which the given t-norm is the strongest one. For the opposite problem, we obtain that there is a fuzzy metric space for which there is no strongest t-norm. As an application of the main results, it is shown that there are infinite non-isometric fuzzy metrics on an infinite set.
PI4K IIα is a critical enzyme for the maintenance of Golgi and is also known to function in the synaptic vesicles. The product of its catalytical function, phosphatidylinositol 4-phosphate (PI4P), is an important lipid molecule because it is a hallmark of the Golgi and TGN, is directly recognized by many proteins and also serves as a precursor molecule for synthesis of higher phosphoinositides. Here, we report crystal structures of PI4K IIα
enzyme in the apo-state and inhibited by calcium. The apo-
structure reveals a surprising rigidity of the active site residues important for catalytic activity. The structure of calcium inhibited kinase reveals how calcium locks ATP in the active site.
We assign to each pair of positive integers $n$ and $k\ge 2$ a digraph $G(n,k)$ whose set of vertices is $H=\{0,1,\dots ,n-1\}$ and for which there is a directed edge from $a\in H$ to $b\in H$ if $a^k\equiv b\pmod n$. We investigate the structure of $G(n,k)$. In particular, upper bounds are given for the longest cycle in $G(n,k)$. We find subdigraphs of $G(n,k)$, called fundamental constituents of $G(n,k)$, for which all trees attached to cycle vertices are isomorphic.
The aim of the paper is to investigate the structure of disjoint iteration groups on the unit circle ${\mathbb{S}^1}$, that is, families ${\mathcal F}=\lbrace F^{v}\:{\mathbb{S}^1}\longrightarrow {\mathbb{S}^1}\; v\in V\rbrace $ of homeomorphisms such that
\[ F^{v_{1}}\circ F^{v_{2}}=F^{v_{1}+v_{2}},\quad v_1, v_2\in V, \] and each $F^{v}$ either is the identity mapping or has no fixed point ($(V, +)$ is an arbitrary $2$-divisible nontrivial (i.e., $\mathop {\mathrm card}V>1$) abelian group).
In this paper we study some special residuated lattices, namely, idempotent residuated chains. After giving some properties of Green's relation $\mathcal D$ on the monoid reduct of an idempotent residuated chain, we establish a structure theorem for idempotent residuated chains. As an application, we give necessary and sufficient conditions for a band with an identity to be the monoid reduct of some idempotent residuated chain. Finally, based on the structure theorem for idempotent residuated chains, we obtain some characterizations of subdirectly irreducible, simple and strictly simple idempotent residuated chains.
Záměr. Cílem studie bylo testování dimensionality české verze Jeffersonské škály empatie pro poskytovatele léčebné péče (JSPE-HP) na podkladě údajů získaných od representativního souboru českých lékařů a testování vlivu věku, pohlaví, délky a typu praxe na jejich výpověď. Soubor a procedura. Soubor tvořilo 1305 respondentů vybraných náhodným kvótním výběrem, dle regionu, pohlaví, věku a způsobu výkonu profese. Výsledky. Struktura nástroje byla nejprve zkoumána EFA a nález následně testován na jiném souboru CFA. Byly identifikovány tři korelované faktory s marginálně akceptovatelnou mírou shody modelu a dat. EFA vyššího řádu se Schmid-Leimanovou ortogonalizací identifikovala obecný faktor „vysvětlující“ 73,3 % rozptylu a 26,7 % rozptylu připadajících na faktory prvního řádu. Cronbachův koeficient alfa byl 0,842 a nebyl zjištěn klinicky závažný efekt věku, pohlaví, typu praxe a profesionální orientace. Neočekávaným nálezem byla relativně nízká průměrná hodnota skóru empatie ve srovnání s americkými lékaři. Výsledky studie naznačují, že česká verze JSPE-HP je jednodimensionální stupnice, psychometricky srovnatelná s US verzí a použitelná pro odhad empatického chování českých lékařů. Omezení studie. Extrapolace nálezů je limitovaná charakteristikami souborů a skutečností, že autoreferenční data nemusí nutně odrážet skutečné chování respondentů., Objectives. The aim of this study was to examine the Jefferson Scale of Physician Empathy (JSPEHP) underlying dimensionality and the relation of empathy scores to age, gender, practice experience, and practice type using responses from a representative sample of Czech physicians. Subjects and setting. The JSPE-HP was administered to a sample of 1,305 respondents selected using the hierarchical random proportional stratified sampling technique representing Czech physicians from the viewpoint of region, practice type, gender, and age. Results. The structure of the instrument was examined using EFA and the findings were tested on different sample using CFA. Three intercorrelated primary factors were identified with a marginally acceptable fit. High-order EFA employing Schmid-Leiman orthgonalization identified a general factor explaining 73.3% of the common variance with 26.7% explained by the first-order factors beyond the general factor. Cronbach’s alpha for total scale was 0.842 and no clinically important effect of age, gender, practice type, and professional orientation on physicians’ empathy score was found. The substantially lower mean empathy score of Czech physicians in comparison to that reported for US physicians is worthy of consideration. The results of this study indicate that the Czech version of JSPE-HP is an unidimensional scale, psychometrically comparable to the US version, and a sound instrument for self-reported assessment of the empathetic behavior of Czech physicians. Study limitation. The extrapolation of findings may be limited as the sample was representative of Czech physicians only from the viewpoint of four variables: region, practice type, gender, and age. Also, a self-report measure of empathy may not be necessarily a reflection of actual behavior in medical practice., and Jiří Kožený, Lýdie Tišanská.
The structure of the unit group of the group algebra of the group $A_4$ over any finite field of characteristic 2 is established in terms of split extensions of cyclic groups.
We give some necessary and sufficient conditions for transitive $l$-permutation groups to be $2$-transitive. We also discuss primitive components and give necessary and sufficient conditions for transitive $l$-permutation groups to be normal-valued.
The problem addressed in this paper is the reconstruction of an object in the form of a realistically textured 3D model from images taken with an uncalibrated camera. We especially focus on reconstructions from {\em short} image sequences. By means of a description of an easy to use system, which is able to accomplish this in a fast and reliable way, we give a survey of all steps of the reconstruction pipeline. For the purpose of developing a coherent reconstruction system it is necessary to integrate a number of different techniques such as feature detection, algorithms of the RANSAC-family, and methods for auto-calibration. We describe and review recent developments of distinct strands of these techniques. While developing our system the necessity of improvements of several steps of the state-of-the-art reconstruction pipeline emerged. Two of these innovations are introduced in detail in this paper: an advanced SIFT-based feature detector and a two-stage RANSAC process facilitating a faster selection of relevant object points. In addition, we give a recommendation regarding auto-calibration for short image sequences.