590 research outputs found
Social Services and Newcomer Families in NYS: Bridging Cultural Differences
This report outlines some of the cultural practices and values of the major newcomer communities represented in New York State. It also describes reasons that some issues tend to arise in newcomer families and ways that social service agencies can take preventative action before issues in families lead to dramatic consequences
The Role of Human-Automation Consensus in Multiple Unmanned Vehicle Scheduling
Objective: This study examined the impact of increasing automation replanning rates on operator performance and workload when supervising a decentralized network of heterogeneous unmanned vehicles. Background: Futuristic unmanned vehicles systems will invert the operator-to-vehicle ratio so that one operator can control multiple dissimilar vehicles connected through a decentralized network. Significant human-automation collaboration will be needed because of automation brittleness, but such collaboration could cause high workload. Method: Three increasing levels of replanning were tested on an existing multiple unmanned vehicle simulation environment that leverages decentralized algorithms for vehicle routing and task allocation in conjunction with human supervision. Results: Rapid replanning can cause high operator workload, ultimately resulting in poorer overall system performance. Poor performance was associated with a lack of operator consensus for when to accept the automation’s suggested prompts for new plan consideration as well as negative attitudes toward unmanned aerial vehicles in general. Participants with video game experience tended to collaborate more with the automation, which resulted in better performance. Conclusion: In decentralized unmanned vehicle networks, operators who ignore the automation’s requests for new plan consideration and impose rapid replans both increase their own workload and reduce the ability of the vehicle network to operate at its maximum capacity. Application: These findings have implications for personnel selection and training for futuristic systems involving human collaboration with decentralized algorithms embedded in networks of autonomous systems.Aurora Flight Sciences Corp.United States. Office of Naval Researc
Progress in Absorber R&D for Muon Cooling
A stored-muon-beam neutrino factory may require transverse ionization cooling
of the muon beam. We describe recent progress in research and development on
energy absorbers for muon-beam cooling carried out by a collaboration of
university and laboratory groups.Comment: 7 pages, 1 figure, presented at the 3rd International Workshop on
Neutrino Factory Based on Muon Storage Rings (NuFACT'01), May 24-30, 2001,
Tsukuba, Japa
Evidence for a three-nucleon-force effect in proton-deuteron elastic scattering
Developments in spin-polarized internal targets for storage rings have
permitted measurements of 197 MeV polarized protons scattering from vector
polarized deuterons. This work presents measurements of the polarization
observables A_y, iT_11, and C_y,y in proton-deuteron elastic scattering. When
compared to calculations with and without three-nucleon forces, the
measurements indicate that three-nucleon forces make a significant contribution
to the observables. This work indicates that three-body forces derived from
static nuclear properties appear to be crucial to the description of dynamical
properties.Comment: 8 pages 2 figures Latex, submitted to Phys. Rev. Letter
Raman coupler for a trapped two-component quantum-degenerate Fermi gas
We investigate theoretically the Raman coupling between two internal states
of a trapped low-density quantum-degenerate Fermi gas. In general, the trap
frequencies associated with the two internal states can be different, leading
to the onset of collapses and revivals in the population difference of the two
internal states. This behavior can be changed drastically by two-body
collisions. In particular, we show that under appropriate conditions they can
suppress the dephasing leading to the collapse of the population difference,
and restore almost full Rabi oscillations between the two internal states.
These results are compared and contrasted to those for a quantum-degenerate
bosonic gas.Comment: 7 pages incl. 7 PostScript figures (.eps), LaTeX using RevTeX4,
submitted to Phys. Rev. A, modified versio
The Modeling of Anisotropic Fuselage Lining Material
In this paper a theoretical model that can account for the effect of lining anisotropy on sound transmission through fuselage structures is developed. The model allows for anisotropic flow resistivity, tortuosity and elastic moduli. Implicit to the theory is a characteristic dispersion relation of sixth order that yields the allowed wave numbers for wave propagation in anisotropic elastic porous media. In addition, explicit expressions for field variables such as displacements and stresses appropriate for anisotropic foams are derived. Predictions of random incidence sound transmission loss for double panels with anisotropic linings have been performed. To verify the prediction, the theoretical results have been compared with random incidence transmission loss measurements
Confirmation of a pi_1^0 Exotic Meson in the \eta \pi^0 System
The exclusive reaction , at 18 GeV has been studied with a partial wave analysis on a sample
of 23~492 events from BNL experiment E852. A mass-dependent fit
is consistent with a resonant hypothesis for the wave, thus providing
evidence for a neutral exotic meson with , a mass of MeV, and a width of MeV. New
interpretations of the meson exotics in neutral system observed in
E852 and Crystal Barrel experiments are discussed.Comment: p3, rewording the paragraph (at the bottom) about the phase
variations. p4, rewording paragrath "The second method ..." . p4, at the
bottom of paragrath "The third method ..." added consistent with the results
of methods 1 and 2
Exotic Meson Production in the System observed in the Reaction at 18 GeV/c
This letter reports results from the partial wave analysis of the
final state in collisions at 18GeV/c.
Strong evidence is observed for production of two mesons with exotic quantum
numbers of spin, parity and charge conjugation, in the decay
channel . The mass MeV/c^2 and
width MeV/c^2 of the first state are consistent
with the parameters of the previously observed . The second
resonance with mass MeV/c^2 and width MeV/c^2 agrees very well with predictions from theoretical
models. In addition, the presence of is confirmed with mass MeV/c^2 and width MeV/c^2
and a new state, , is observed with mass
MeV/c^2 and width MeV/c^2. The decay properties of
these last two states are consistent with flux tube model predictions for
hybrid mesons with non-exotic quantum numbers
Recommended from our members
An update for the MuCool test area
Construction of a new facility known as the MuCool Test Area (MTA) has been completed at Fermi National Accelerator Laboratory. This facility supports research in new accelerator technologies for future endeavors such as a Neutrino Factory or Muon Collider. During the summer of 2004, an initial set of tests was completed for the filling of a convection-style liquid hydrogen absorber designed by KEK. The absorber contained 6.2 liquid liters of hydrogen and was tested for a range of heating conditions to quantify the absorber's heat exchanger performance. Future work at Fermilab includes the design, construction, and installation of a forced-flow absorber to be used with other components built to investigate the properties of a muon ionization cooling channel. A Tevatron-style refrigerator/compressor building is to be operational by spring of 2006 in support of the absorber tests and also to provide 5-K helium and liquid nitrogen to a 5-T solenoid magnet, an active element of the future test apparatus. The refrigerator will be configured in such a manner as to meet the 5 K and 14-20-K helium needs of the MTA. This paper reviews the challenges and successes of the past KEK absorber tests as well as looks into the future cryogenic capabilities and intentions of the site
- …