17,268 research outputs found
Collaborating to develop an online resource for parents
Background The development and evaluation of Online Parent Information and Support (OPIS) involved the creation of a web resource for parents who needed support for the home-based management of their child's chronic kidney disease (CKD)
Perceptual thresholds for the effects of room modes as a function of modal decay
Room modes cause audible artefacts in listening environments. Modal control approaches have emerged in scientific literature over the years and, often, their performance is measured by criteria that may be perceptually unfounded. Previous research has shown modal decay as a key perceptual factor in detecting modal effects. In this work, perceptual thresholds for the effects of modes as a function of modal decay have been measured in the region between 32Hz and 250Hz. A test methodology has been developed to include modal interaction and temporal masking from musical events, which are important aspects in recreating an ecologically valid test regime. This method has been deployed in addition to artificial test stimuli traditionally used in psychometric studies, which provide unmasked, absolute thresholds. For artificial stimuli, thresholds decrease monotonically from 0.9 seconds at 32 Hz to 0.17 seconds at 200 Hz, with a knee at 63 Hz. For music stimuli, thresholds decrease monotonically from 0.51 seconds at 63 Hz to 0.12 seconds at 250 Hz. Perceptual thresholds are shown to be dependent on frequency and to a much lesser extent on level. Results presented here define absolute and practical thresholds, which are useful as perceptually relevant optimization targets for modal control methods
Nonadiabatic Electronic Interactions In The Ion-Pair States Of NelCl
Nonadiabatic interactions in the NeIC1 van der Waals complex have been explored in the lowest energy triad of IC1 ion-pair states (approximately 39 000 cm-1). Dispersed fluorescence measurements reveal emission characteristic of multiple ion-pair electronic states, with the relative contributions from the E(O+ ), beta(1), and D\u27(2) states changing with the initial IC1 vibrational excitation (v(IC1)). Emission directly from NeIC1 (v(IC1) = O) complexes indicates that the initially prepared NeIC1 levels have mixed electronic character and that the IC1 electronic parentage changes with the initial van der Waals vibrational level selected. NeIC1 complexes prepared with 1-4 quanta of IC1 stretch undergo rapid vibrational predissociation with a strong propensity for DELTA-V(IC1) = - 1 relaxation. The electronic state(s) populated in the IC1 fragments differ from the mixed electronic character of the initially prepared level, demonstrating that vibrational predissociation is accompanied by nonadiabatic electronic state changing processes. The observed final state selectivity may be attributed to the relative strength of the nonadiabatic couplings between the initial NeIC1 bound state and the final IC1 states or a momentum gap rationale based on the overlap between the NeIC1 bound state wave function and the highly oscillatory continuum wave function of the separating fragments
Shuttle passenger couch
Conceptual design and fabrication of a full scale shuttle passenger couch engineering model are reported. The model was utilized to verify anthropometric dimensions, reach dimensions, ingress/egress, couch operation, storage space, restraint locations, and crew acceptability. These data were then incorported in the design of the passenger couch verification model that underwent performance tests
Extended Bose-Hubbard model with incompressible states at fractional numbers
The Bose-Hubbard model is extended to include nearest and far neighbor
interactions and is related to the fractional quantum Hall effect (FQHE). Both
models may be studied in optical lattices with quantum gases. The ground state
is calculated for the extended Bose-Hubbard model with strong repulsive
interactions (weak hopping). Incompressible Mott insulator states are found at
rational filling fractions compatible with the principal and secondary FQHE
filling fractions of the lowest Landau levels observed experimentally. It is
discussed to which extent these states at fractional filling survive or
undergoes a Mott insulator transition to a superfluid as hopping terms are
included.Comment: Revised version, to appear in PR
A reliable liquid helium detector
Detector and indicator system, utilizing commercial perforated germanium cryogenic thermometer as level sensor containing adjustable level discriminator with indicators, operates reliably over pressure range from 50 to 900 mm Hg without electronic adjustments
Approaches to liberalizing services
Inly since completion of the Uruguay Round have developing countries in East AsOnly since completion of the Uruguay Round have developing countries in East Asia and the Western Hemisphere shown interest in liberalizing services. Ambitious effortsare now being made to incorporate services in liberalization objectives of both sub-regional and regional integration efforts, including in the Asia-Pacific region under APEC and in the Western Hemisphere under the Free Trade Area of the Americas (FTAA) process. At the sub-regional level, member countries of both ASEAN (in East Asia) and MERCOSUR (in Latin America) have chosen to follow the liberalization model set forth in the World Trade Organization's (WTO) General Agreement on Trade in Services (GATS), and to open their services markets gradually and piecemeal. In the Western Hemisphere, Mexico has successfully promoted the NAFTA model of a more comprehensive liberalization of services markets - and several Latin American countries have adopted the same approach. Regionally, APEC has chosen a concerted voluntary approach to liberalizing services markets. Within the Western Hemisphere, participants are defining which approach they will use in the negotiations on services launched as part of the FTAA in April 1998. In all these efforts, a stated desire to promote more efficient services markets is often hindered by reluctance to open services markets rapidly or comprehensively because of historically entrenched protectionism in the sector and ignorance of the regulatory measures that impede trade in services. Presumably it would be easier to liberalize services at the sub-regional level, among countries at similar stages of development (although the liberalization's economic value there might be questioned). Liberalizing services at the broader regional level is a difficult and ambitious goal, given the diversity of countries involved in such efforts. Thus liberalization will probably move more slowly at the regional than at the sub-regional level - perhaps even more slowly than at the multilateral level. It is possible that the new round of multilateral talks on services scheduled to begin under the WTO in 2000 may well eclipse the recently begun regional efforts.Economic Theory&Research,Payment Systems&Infrastructure,Decentralization,Enterprise Development&Reform,ICT Policy and Strategies,Economic Theory&Research,Health Economics&Finance,Trade and Services,Governance Indicators,ICT Policy and Strategies
From Perturbation Theory to Confinement: How the String Tension is built up
We study the spatial volume dependence of electric flux energies for SU(2)
Yang-Mills fields on the torus with twisted boundary conditions. The results
approach smoothly the rotational invariant Confinement regime. The would-be
string tension is very close to the infinite volume result already for volumes
of . We speculate on the consequences of our result for
the Confinement mechanism.Comment: 6p, ps-file (uuencoded). Contribution to Lattice'93 Conference
(Dallas, 1993). Preprint INLO-PUB 18/93, FTUAM-93/4
Rovibrational Resonance Effects In Collision-Induced Electronic Energy Transfer: I2(E,v=0-2)+CF4
Collisions of I-2 in the E(0(g)(+)) electronic state with CF4 molecules induce electronic energy transfer to the nearby D, beta, and D-\u27 ion-pair states. Simulations of dispersed fluorescence spectra reveal collision-induced electronic energy transfer rate constants and final vibrational state distributions within each final electronic state. In comparison with earlier reports on I-2(upsilon(E)=0-2) collisions with He or Ar atoms, we find markedly different dynamics when I-2, excited to the same rovibronic states, collides with CF4. Final vibrational state distributions agree with the associated Franck-Condon factors with the initially prepared state to a greater degree than those found with He or Ar collision partners and suggest that internal degrees of freedom in the CF4 molecule represent a substantial means for accepting the accompanying loss of I-2 vibronic energy. Comparison of the E -\u3e D transfer of I-2 excited to the J=23 and J=55 levels of the upsilon(E)=0 state reveals the onset of specific, nonstatistical dynamics as the available energy is increased above the threshold for excitation of the low frequency nu(2) bending mode of CF4. (c) 2006 American Institute of Physics
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