By a torsion of a general connection $\Gamma $ on a fibered manifold $Y\rightarrow M$ we understand the Frölicher-Nijenhuis bracket of $\Gamma $ and some canonical tangent valued one-form (affinor) on $Y$. Using all natural affinors on higher order cotangent bundles, we determine all torsions of general connections on such bundles. We present the geometrical interpretation and study some properties of the torsions.
One of the most important problems in communication network design is the stability of network after any disruption of stations or links. Since a network can be modeled by a graph, this concept is examined under the view of vulnerability of graphs. There are many vulnerability measures that were defined in this sense. In recent years, measures have been defined over some vertices or edges having specific properties. These measures can be considered to be a second type of measures. Here we define a new measure of the second type called the total accessibility. This measure is based on accessible sets of a graph. In our study we give the total accessibility number of well known graph models such as Pn, Cn, Km,n, W1,n, K1,n. We also examine this new measure under operations on graphs. A simple algorithm, which calculates the total accessibility number of graphs, is given. We observe that when any two graphs of the same size are compared in stability, it is inferred that the graph of higher total accessibility number is more stable than the other one. All the graphs considered in this paper are undirected, loopless and connected.
Let $S$ and $R$ be two associative rings, let $ _{S}C_{R}$ be a semidualizing $(S,R)$-bimodule. We introduce and investigate properties of the totally reflexive module with respect to $_{S}C_{R}$ and we give a characterization of the class of the totally $C_{R}$-reflexive modules over any ring $R$. Moreover, we show that the totally $C_{R}$-reflexive module with finite projective dimension is exactly the finitely generated projective right $R$-module. We then study the relations between the class of totally reflexive modules and the Bass class with respect to a semidualizing bimodule. The paper contains several results which are new in the commutative Noetherian setting.
This article examines three memoirs by survivors of the Terezín (in German, Theresienstadt) ghetto, and especially their testimony about the cultural life of the ghetto, in the context of postwar reintegration. All Czech‑Jewish survivors of the concentration camps returned to a society very different from the prewar Czechoslovakia they remembered. Many found themselves struggling to adapt to the complete rejection of German‑language culture, the shift to the political left, and postwar anti‑S emitism. The authors of these three memoirs were all over sixty years of age, were all bilingual, and before the war had served as ambassadors between Czech‑ and German‑language culture. In their postwar memoirs, published in Czech, they employed their descriptions of the cultural life of the ghetto as a reintegration technique. That is, by describing their intense love of the specifically Czech works performed in Terezín, they attempted to establish common ground with their non‑Jewish fellow Czechs and overcome the suspicion engendered by their prewar association with German‑language culture.
In the current philosophical literature, determinism is rarely defined explicitly. This paper attempts to show that there are in fact many forms of determinism, most of which are familiar, and that these can be differentiated according to their particular components. Recognizing the composite character of determinism is thus central to demarcating its various forms. and V současné filozofické literatuře je determinismus zřídka výslovně definován. Tento dokument se snaží ukázat, že ve skutečnosti existuje mnoho forem determinismu, z nichž většina je známá, a že tyto mohou být diferencovány podle jejich jednotlivých složek. Rozpoznání kompozitního charakteru determinismu je tak zásadní pro vymezení jeho různých forem.