14,883 research outputs found
Construction of SU(3) irreps in canonical SO(3)-coupled bases
Alternative canonical methods for defining canonical SO(3)-coupled bases for
SU(3) irreps are considered and compared. It is shown that a basis that
diagonalizes a particular linear combination of SO(3) invariants in the SU(3)
universal enveloping algebra gives basis states that have good quantum
numbers in the asymptotic rotor-model limit.Comment: no figure
Coherent state triplets and their inner products
It is shown that if H is a Hilbert space for a representation of a group G,
then there are triplets of spaces F_H, H, F^H, in which F^H is a space of
coherent state or vector coherent state wave functions and F_H is its dual
relative to a conveniently defined measure. It is shown also that there is a
sequence of maps F_H -> H -> F^H which facilitates the construction of the
corresponding inner products. After completion if necessary, the F_H, H, and
F^H, become isomorphic Hilbert spaces. It is shown that the inner product for H
is often easier to evaluate in F_H than F^H. Thus, we obtain integral
expressions for the inner products of coherent state and vector coherent state
representations. These expressions are equivalent to the algebraic expressions
of K-matrix theory, but they are frequently more efficient to apply. The
construction is illustrated by many examples.Comment: 33 pages, RevTex (Latex2.09) This paper is withdrawn because it
contained errors that are being correcte
Examining the relationship of dieting behavior and substance use among female adolescents
Indiana University-Purdue University Indianapolis (IUPUI)The problem behavior theory suggests that the engagement in one problematic behavior increases the likelihood of engagement in another problematic behavior. Previous research has found among youth an increasing probability of co-occurring dieting and substance use behavior, particularly among girls. However, to date findings are inconclusive on the temporal ordering of these behaviors. Further, limited research has been conducted to explore whether the temporal ordering of the two behaviors exist similarly between White and Black youth. The present study will use a cross-lagged panel design across one year to examine the temporal ordering between dieting behavior and substance use among a sample of 2,016 adolescent females (grade mean=7; 77.2% White; 22.8% Black). We hypothesized that a bidirectional relationship would be observed between the two behaviors. However, given no published studies on this relationship by race, no a priori hypotheses were made for this second aim. Result showed that within the full sample dieting behavior significantly predicted substance use one year later, but the inverse relationship was not found. Additionally, this effect was replicated in the White sample but null effects in both directions was found among Black youth. These findings provide support for a temporal relationship between dieting behavior and substance use, such that the former predicts risk for the latter. Moreover, although there is evidence of race differences in the risk pathway, further research is needed to confirm this effect. Future studies are also needed to determine whether this observed temporal relationship is present among adolescent females of other racial/ethnic groups, as well as if the relationship varies as a function of other demographic variables, such as age (e.g., early, mid, or late-adolescence)
Integrating case-based reasoning and hypermedia documentation: an application for the diagnosis of a welding robot at Odense steel shipyard
Reliable and effective maintenance support is a vital consideration for the management within today's manufacturing environment. This paper discusses the development of a maintenance system for the world's largest robot welding facility. The development system combines a case-based reasoning approach for diagnosis with context information, as electronic on-line manuals, linked using open hypermedia technology. The work discussed in this paper delivers not only a maintenance system for the robot stations under consideration, but also a design framework for developing maintenance systems for other similar applications
The Tamm-Dancoff Approximation as the boson limit of the Richardson-Gaudin equations for pairing
A connection is made between the exact eigen states of the BCS Hamiltonian
and the predictions made by the Tamm-Dancoff Approximation. This connection is
made by means of a parametrised algebra, which gives the exact quasi-spin
algebra in one limit of the parameter and the Heisenberg-Weyl algebra in the
other. Using this algebra to construct the Bethe Ansatz solution of the BCS
Hamiltonian, we obtain parametrised Richardson-Gaudin equations, leading to the
secular equation of the Tamm-Dancoff Approximation in the bosonic limit. An
example is discussed in depth.Comment: Submitted to the proceedings of the Group28 conference
(Newcastle-upon-Tyne, UK). Journal of Physics: Conference Serie
Economic Development in Kentucky: The Integration of Politics, Government and Economic Policy from the Founding Fathers to the Present
A thesis presented to the faculty of the College of the Institute for Regional Analysis and Public Policy at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Public Administration by Joe T. Rowe on April 16, 2008
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