317 research outputs found
Model-based training of manual procedures in automated production systems
Maintenance engineers deal with increasingly complex automated production
systems (aPSs). Such systems are characterized by an increasing computerization
or the addition of robots that collaborate with human workers. The effects of
changing or replacing components of such systems are difficult to assess since
there are complex interdependencies between process parameters and the state of
the components. This paper proposes a model-based training system that
visualizes these interdependencies using domain-independent SysML models. The
training system consists of a virtual training system for initial training and
an online support system for assistance during maintenance or changeover
procedures. Both systems use structural SysML models to visualize the state of
the machine at a certain step of a procedure. An evaluation of the system in a
changeover procedure against a paper-based manual showed promising results
regarding effectiveness, usability and attractiveness.Comment: 25 pages,
https://www.sciencedirect.com/science/article/pii/S095741581830080
Inelastic nucleon contributions in nuclear response functions
We estimate the contribution of inelastic nucleon excitations to the
inclusive cross section in the CEBAF kinematic range.
Calculations are based upon parameterizations of the nucleon structure
functions measured at SLAC. Nuclear binding effects are included in a
vector-scalar field theory, and are assumed have a minimal effect on the
nucleon excitation spectrum. We find that for q\lsim 1 GeV the elastic and
inelastic nucleon contributions to the nuclear response functions are
comparable, and can be separated, but with roughly a factor of two uncertainty
in the latter from the extrapolation from data. In contrast, for q\rsim 2 GeV
this uncertainty is greatly reduced but the elastic nucleon contribution is
heavily dominated by the inelastic nucleon background.Comment: 20 pages, 7 figures available from the authors at Department of
Physics and Astronomy, University of Rochester, Rochester NY 1462
Evaluation of in vitro penetration of fluticasone propionate from MP-AzeFlu and fluticasone propionate nasal spray through EpiAirway (TM) 606 tissues using vertical diffusion cells
Purpose: Most patients with allergic rhinitis (AR) have moderate-to-severe disease, requiring complete and prompt relief when symptoms occur. The time course of fluticasone propionate (FP) penetration into nasal tissues after intranasal administration is not well characterized. The goal of this proof-of-concept study was to evaluate the mucosal penetration of FP from fixed-combination FP-azelastine nasal spray (MP-AzeFlu) compared with an FP-only nasal spray in an in vitro, 3-dimensional human bronchial tissue model. Materials and Methods: Absorption of FP from MP-AzeFlu and FP nasal spray was modeled using EpiAirway (TM) 606 (MatTek Corporation; Ashland, MA, USA) tissue cultured in vertical diffusion cells. The dosing amount of MP-AzeFlu was optimized in a pilot study. Based on the results of the pilot study, 10 mu L of MP-AzeFlu (3.65 mu g; n = 8) and 10 mu L of FP nasal spray (5.00 mu g; n = 8) were evaluated for penetration of tissue. Tissue integrity was monitored with Lucifer yellow. FP in the receiving media was quantified for each sample using liquid chromatography with tandem mass spectrometry. Results: MP-AzeFlu and FP nasal spray were associated with similar FP accumulation profiles in the receiving media, but the permeability of FP was greater for MP-AzeFlu during hours 0 to 6, suggesting faster absorption for MP-AzeFlu. No indications of compromised tissue integrity were found in any of the tested cells. Conclusion: The higher and more rapid penetration of FP from MP-AzeFlu supports the use of MP-AzeFlu for patients with AR, particularly when prioritizing fast and pronounced symptom relief
Seniority number in spin-adapted spaces and compactness of configuration interaction wave functions
This work extends the concept of seniority number, which has been widely used for classifying N-electron Slater determinants, to wave functions of N electrons and spin S, as well as to N-electron spin-adapted Hilbert spaces. We propose a spin-free formulation of the seniority number operator and perform a study on the behavior of the expectation values of this operator under transformations of the molecular basis sets. This study leads to propose a quantitative evaluation for the convergence of the expansions of the wave functions in terms of Slater determinants. The non-invariant character of the seniority number operator expectation value of a wave function with respect to a unitary transformation of the molecular orbital basis set, allows us to search for a change of basis which minimizes that expectation value. The results found in the description of wave functions of selected atoms and molecules show that the expansions expressed in these bases exhibit a more rapid convergence than those formulated in the canonical molecular orbital bases and even in the natural orbital ones.Fil: Alcoba, Diego Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Torre, Alicia. Universidad del País Vasco. Facultad de Ciencia y Tecnología. Departamento de Química Física; España;Fil: Lain, Luis. Universidad del País Vasco. Facultad de Ciencia y Tecnología. Departamento de Química Física; España;Fil: Massaccesi, Gustavo Ernesto. Universidad de Buenos Aires. Ciclo Básico Común; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; ArgentinaFil: Oña, Ofelia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentin
Configuration interaction wave functions: A seniority number approach
This work deals with the configuration interaction method when an N-electron Hamiltonian is projected on Slater determinants which are classified according to their seniority number values. We study the spin features of the wave functions and the size of the matrices required to formulate states of any spin symmetry within this treatment. Correlation energies associated with the wave functions arising from the seniority-based configuration interaction procedure are determined for three types of molecular orbital basis: canonical molecular orbitals, natural orbitals, and the orbitals resulting from minimizing the expectation value of the N-electron seniority number operator. The performance of these bases is analyzed by means of numerical results obtained from selected N-electron systems of several spin symmetries. The comparison of the results highlights the efficiency of the molecular orbital basis which minimizes the mean value of the seniority number for a state, yielding energy values closer to those provided by the full configuration interaction procedure.Fil: Alcoba, Diego Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Torre, Alicia. Universidad del Pais Vasco; EspañaFil: Lain, Luis . Universidad del Pais Vasco; EspañaFil: Massaccesi, Gustavo Ernesto. Universidad de Buenos Aires. Ciclo Básico Común; ArgentinaFil: Oña, Ofelia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentin
Improved lower bounds for the ground-state energy of many-body systems
New lower bounds for the binding energy of a quantum-mechanical system of
interacting particles are presented. The new bounds are expressed in terms of
two-particle quantities and improve the conventional bounds of the Hall-Post
type. They are constructed by considering not only the energy in the
two-particle system, but also the structure of the pair wave function. We apply
the formal results to various numerical examples, and show that in some cases
dramatic improvement over the existing bounds is reached.Comment: 29 pages, 5 figures, to be published in Phys. Rev.
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