48,013 research outputs found
Using C-Tool to simulate soil carbon and radiocarbon development
Tho model framework C-TOOL was used to simulate soil carbon and radiocarbon development. A simple three-compartment model was sufficient for describing the data
A survey of the effect of grooved runway operations on the wear of commercial airline tires
Effect of grooved runway operations on wear of commercial airline tire
Hamiltonian Reduction of -theories at the Level of Correlators
Since the work of Bershadsky and Ooguri and Feigin and Frenkel it is well
known that correlators of current algebra for admissible
representations should reduce to correlators for conformal minimal models. A
precise proposal for this relation has been given at the level of correlators:
When primary fields are expressed as with being
a variable to keep track of the representation multiplet (possibly
infinitely dimensional for admissible representations), then the minimal model
correlator is supposed to be obtained simply by putting all . Although
strong support for this has been presented, to the best of our understanding a
direct, simple proof seems to be missing so in this paper we present one based
on the free field Wakimoto construction and our previous study of that in the
present context. We further verify that the explicit correlators we
have published in a recent preprint reduce in the above way, up to a constant
which we also calculate. We further discuss the relation to more standard
formulations of hamiltonian reduction.Comment: 13 pages, LaTe
Survey of Australian father\u27s attitudes towards infant vaccination: Findings from the Australian Father\u27s Study
Objective: To investigate the attitudes of expectant Australian fathers towards vaccination, and to identify factors which may influence these attitudes.
Methods: A cross-sectional survey study of 407 Australian men with expectant partners, mean age 30.4 (SD 6.7). Self reported attitude, level of knowledge and information resources accessed regarding pregnancy related issues. Participant demographics collected included: Age, number of children, relationship status, level of education, employment information and smoking status.
Results: Majority (89%) of participants had a positive attitude towards infant vaccination, 9% felt neutral and 2% had negative attitudes. Positive attitudes towards vaccination were associated with lower self-reported knowledge of pregnancy issues but a higher likelihood of discussing pregnancy issues with health care providers rather than sourcing information from the internet (both p\u3c0.001).
Conclusion: A majority of Australian expectant fathers have a positive attitude towards infant vaccination. Fathers with negative attitudes to vaccination self-reported higher levels of knowledge. They were more likely to obtain information from the Internet instead of healthcare staff.
Implication for public health: Including fathers in health discussion with knowledgeable health care providers may result in increased vaccine uptake
Extended Superconformal Algebras from Classical and Quantum Hamiltonian Reduction
We consider the extended superconformal algebras of the Knizhnik-Bershadsky
type with -algebra like composite operators occurring in the commutation
relations, but with generators of conformal dimension 1, and 2,
only. These have recently been neatly classified by several groups, and we
emphasize the classification based on hamiltonian reduction of affine Lie
superalgebras with even subalgebras . We reveiw the situation
and improve on previous formulations by presenting generic and very compact
expressions valid for all algebras, classical and quantum. Similarly generic
and compact free field realizations are presented as are corresponding
screening charges. Based on these a discussion of singular vectors is
presented. (Based on talk by J.L. Petersen at the Int. Workshop on "String
Theory, Quantum Gravity and the Unification of the Fundamental Interactions",
Rome Sep. 21-26, 1992)Comment: 30 pages, NBI-HE-92-8
European lessons for Green and Blue Services in The Netherlands
Green and Blue Services were developed in The Netherlands to reward farmers for the environmental services they provide to society. Especially the first initiatives were area specific, developed together with farmers and different from the national Agri-environmental scheme. In the PLUREL case study region Haaglanden, Green and Blue Services are seen as a strategy to strengthen agriculture in the urban fringe
Directed flow, a signal for the phase transition in Relativistic Nuclear Collisions?
The sign change of the slope of the directed flow of baryons has been
predicted as a signal for a first order phase transition within fluid dynamical
calculations. Recently, the directed flow of identified particles has been
measured by the STAR collaboration in the beam energy scan (BES) program. In
this article, we examine the collision energy dependence of directed flow
in fluid dynamical model descriptions of heavy ion collisions for
GeV. The first step is to reproduce the existing
predictions within pure fluid dynamical calculations. As a second step we
investigate the influence of the order of the phase transition on the
anisotropic flow within a state-of-the-art hybrid approach that describes other
global observables reasonably well. We find that, in the hybrid approach, there
seems to be no sensitivity of the directed flow on the equation of state and in
particular on the existence of a first order phase transition. In addition, we
explore more subtle sensitivities like e.g. the Cooper-Frye transition
criterion and discuss how momentum conservation and the definition of the event
plane affects the results. At this point, none of our calculations matches
qualitatively the behavior of the STAR data, the values of the slopes are
always larger than in the data.Comment: 7 pages, 7 figure
Nonsquare Spectral Factorization for Nonlinear Control Systems
This paper considers nonsquare spectral factorization of nonlinear input affine state space systems in continuous time. More specifically, we obtain a parametrization of nonsquare spectral factors in terms of invariant Lagrangian submanifolds and associated solutions of Hamilton–Jacobi inequalities. This inequality is a nonlinear analogue of the bounded real lemma and the control algebraic Riccati inequality. By way of an application, we discuss an alternative characterization of minimum and maximum phase spectral factors and introduce the notion of a rigid nonlinear system.
A Derivation of Moment Evolution Equations for Linear Open Quantum Systems
Given a linear open quantum system which is described by a Lindblad master
equation, we detail the calculation of the moment evolution equations from this
master equation. We stress that the moment evolution equations are well-known,
but their explicit derivation from the master equation cannot be found in the
literature to the best of our knowledge, and so we provide this derivation for
the interested reader
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