53,386 research outputs found
Palindromic complexity of infinite words associated with simple Parry numbers
A simple Parry number is a real number \beta>1 such that the R\'enyi
expansion of 1 is finite, of the form d_\beta(1)=t_1...t_m. We study the
palindromic structure of infinite aperiodic words u_\beta that are the fixed
point of a substitution associated with a simple Parry number \beta. It is
shown that the word u_\beta contains infinitely many palindromes if and only if
t_1=t_2= ... =t_{m-1} \geq t_m. Numbers \beta satisfying this condition are the
so-called confluent Pisot numbers. If t_m=1 then u_\beta is an Arnoux-Rauzy
word. We show that if \beta is a confluent Pisot number then P(n+1)+ P(n) =
C(n+1) - C(n)+ 2, where P(n) is the number of palindromes and C(n) is the
number of factors of length n in u_\beta. We then give a complete description
of the set of palindromes, its structure and properties.Comment: 28 pages, to appear in Annales de l'Institut Fourie
Delphine Red Shirt: George Sword's Warrior Narratives: Compositional Processes in Lakota Oral Tradition
George Sword an Oglala Lakota (1846–1914) learned to write in order to transcribe and preserve his people’s oral narratives. In her book Delphine Red Shirt, also Oglala Lakota and a native speaker, examines the compositional processes of George Sword and shows how his writings reflect recurring themes and story patterns of the Lakota oral tradition. Her book invites further studies in several areas including literature, translation studies and more. My review of her book suggests some ways it could be used as a primary resource book in developing curricula in Indigenous philosoph
Intercultural ethics: questions of methods in language and intercultural communication
This paper explores how questions of ethics and questions of method are intertwined and unavoidable in any serious study of language and intercultural communication. It argues that the focus on difference and solution orientations to intercultural conflict has been a fundamental driver for theory, data collection and methods in the field. These approaches, the paper argues, have created a considerable consciousness raising industry, with methods, trainings and ‘critical incidents’, which ultimately focus intellectual energy in areas which may be productive in terms of courses and publications but which have a problematic basis in their ethical terrain.
Dieser Artikel untersucht wie ethische und methodische Fragen nicht nur ineinander greifen, sondern in keiner ernstzunehmenden Studie ueber Sprache und interkulturelle Kommunikation ausgelassen werden duerfen. Es wird hier argumentiert, dass der Schwerpunkt auf Verschiedenheit und Problemorientierung im interkulturellen Konflikt einen wesentlichen Einfluss auf theoretische Entwicklungen, Datenerhebung und Methoden in diesem Bereich hatte. Dieser Artikel legt auch dar, wie diese Ansaetze eine betraechtliche ‘Bewusstseinsbildungs – Branche' erzeugt haben, mit Methoden, Trainings, und ‘kritischen Interaktionssituationen’, welche letztendlich allen intellektuellen Arbeitseifer auf Bereiche konzentriert hat, die zwar ertragreich sind in Bezug auf Kurse und Publikationen, jedoch eine problematische Grundlage im ethischen Bereich aufweisen
The rationality of Sol manifolds
Let be the fundamental group of a manifold modeled on three
dimensional Sol geometry. We prove that has a finite index subgroup
which has a rational growth series with respect to a natural generating
set. We do this by enumerating by a regular language. However, in contrast
to most earlier proofs of this sort our regular language is not a language of
words in the generating set, but rather reflects a different geometric
structure in .Comment: 30 pages; author's name changed to agree with published version; to
appear in Journal of Algebr
e-Social Science and Evidence-Based Policy Assessment : Challenges and Solutions
Peer reviewedPreprin
Markovian dynamics of concurrent systems
Monoid actions of trace monoids over finite sets are powerful models of
concurrent systems---for instance they encompass the class of 1-safe Petri
nets. We characterise Markov measures attached to concurrent systems by
finitely many parameters with suitable normalisation conditions. These
conditions involve polynomials related to the combinatorics of the monoid and
of the monoid action. These parameters generalise to concurrent systems the
coefficients of the transition matrix of a Markov chain.
A natural problem is the existence of the uniform measure for every
concurrent system. We prove this existence under an irreducibility condition.
The uniform measure of a concurrent system is characterised by a real number,
the characteristic root of the action, and a function of pairs of states, the
Parry cocyle. A new combinatorial inversion formula allows to identify a
polynomial of which the characteristic root is the smallest positive root.
Examples based on simple combinatorial tilings are studied.Comment: 35 pages, 6 figures, 33 reference
Agglomerative Algebras
This paper investigates a generalization of Boolean algebras which I call agglomerative algebras. It also outlines two conceptions of propositions according to which they form an agglomerative algebra but not a Boolean algebra with respect to conjunction and negation
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