101 research outputs found
Coxeter discriminants and logarithmic Frobenius structures
We consider a class of solutions of the WDVV equation related to the special
systems of covectors (called -systems) and show that the corresponding
logarithmic Frobenius structures can be naturally restricted to any
intersection of the corresponding hyperplanes. For the Coxeter arrangements the
corresponding structures are shown to be almost dual in Dubrovin's sense to the
Frobenius structures on the strata in the discriminants discussed by Strachan.
For the classical Coxeter systems this leads to the families of -systems
from the earlier work by Chalykh and Veselov. For the exceptional Coxeter
systems we give the complete list of the corresponding -systems. We
present also some new families of -systems, which can not be obtained in
such a way from the Coxeter systems.Comment: 28 pages, minor corrections mad
Singularity, complexity, and quasi--integrability of rational mappings
We investigate global properties of the mappings entering the description of
symmetries of integrable spin and vertex models, by exploiting their nature of
birational transformations of projective spaces. We give an algorithmic
analysis of the structure of invariants of such mappings. We discuss some
characteristic conditions for their (quasi)--integrability, and in particular
its links with their singularities (in the 2--plane). Finally, we describe some
of their properties {\it qua\/} dynamical systems, making contact with
Arnol'd's notion of complexity, and exemplify remarkable behaviours.Comment: Latex file. 17 pages. To appear in CM
Generalized Calogero-Moser systems from rational Cherednik algebras
We consider ideals of polynomials vanishing on the W-orbits of the
intersections of mirrors of a finite reflection group W. We determine all such
ideals which are invariant under the action of the corresponding rational
Cherednik algebra hence form submodules in the polynomial module. We show that
a quantum integrable system can be defined for every such ideal for a real
reflection group W. This leads to known and new integrable systems of
Calogero-Moser type which we explicitly specify. In the case of classical
Coxeter groups we also obtain generalized Calogero-Moser systems with added
quadratic potential.Comment: 36 pages; the main change is an improvement of section 7 so that it
now deals with an arbitrary complex reflection group; Selecta Math, 201
GABRIELA : a new detector array for gamma-ray and conversion electron spectroscopy of transfermium elements
With the aid of the Geant4 Monte Carlo simulation package a new detection
system has been designed for the focal plane of the recoil separator VASSILISSA
situated at the Flerov Laboratory of Nuclear Reactions, JINR, Dubna. GABRIELA
(Gamma Alpha Beta Recoil Investigations with the Electromagnetic Analyser
VASSILISSA) has been optimised to detect the arrival of reaction products and
their subsequent radioactive decays involving the emission of alpha- and
beta-particles, fission fragments, gamma- and X-rays, and conversion electrons.
The new detector system is described and the results of the first commissioning
experiments are presented.Comment: 24 pages, Submitted to NIM
The effects of conflict role and intensity on preschoolers’ expectations about peer conflict
Using a puppet procedure depicting hypothetical conflict involving the participant and a peer, 96 preschoolers’ (48 boys and 48 girls; M 1/4 5.14 years, SD 1/4 0.78 years) expectations about peer conflict were assessed as a function of their role in the conflict (i.e., initiator of or responder to initial provocation) and the intensity level of the conflict. Initiators of conflict expected less conflict escalation and subsequent problems with the same peer from the conflict than did responders, particularly following low-intensity conflict. Findings also indicated that, for low-intensity but not high-intensity conflict, girls expected the same peer to provoke them during a subsequent interaction more often than did boys. Results provide further support for assessing preschoolers’ understanding of conflict and are consistent with previous work demonstrating a self-serving bias in young children’s perceptions and reports of their conflicts with other children. Moreover, findings are discussed in terms of their implications for the development of peer relations.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
A pilot ASKAP survey of radio transient events in the region around the intermittent pulsar PSR J1107-5907
Biostimulation of inoculation with Glomus proliferum and application of humic acid in the in vitro growth of Lunularia cruciata
Some Aspects of Latent Structure Analysis
Latent structure models involve real, potentially observable variables and latent, unobservable variables. The framework includes various particular types of model, such as factor analysis, latent class analysis, latent trait analysis, latent profile models, mixtures of factor analysers, state-space models and others. The simplest scenario, of a single discrete latent variable, includes finite mixture models, hidden Markov chain models and hidden Markov random field models. The paper gives a brief tutorial of the application of maximum likelihood and Bayesian approaches to the estimation of parameters within these models, emphasising especially the fact that computational complexity varies greatly among the different scenarios. In the case of a single discrete latent variable, the issue of assessing its cardinality is discussed. Techniques such as the EM algorithm, Markov chain Monte Carlo methods and variational approximations are mentioned
Masculinities, affect and the (re)place(ment) of stardom in Formula One fan leisure practices
Writing from an autoethnographic perspective, this article explores male leisure practices via the mediated relationships fans enter into with stars. More specifically, my own fandom for Formula One driver Jacques Villeneuve is the locus of study, revealing how this affective investment shapes and furnishes my corresponding leisure practices. Notions of gendered 'performativity' come to the fore, with my own displays evoking, enacting and revealing oscillating performances of masculinity. Moreover, there are interesting gendered dynamics that such fan leisure practices flag in terms of the intersection of female/male relationships and the potential 'fantasy' and/or narcissistic readings that a male fan identifying with and performing as another male sport star afford. Finally, my research reveals paradoxes for contemporary masculinities, with fans reliant upon mediation and commodification to facilitate and sustain their performative roles. © 2011 Taylor & Francis
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