561 research outputs found
An assessment system for rating scientific journals in the field of ergonomics and human factors
A method for selecting and rating scientific and professional journals representing the discipline of ergonomics and human factors is proposed. The method is based upon the journal list, impact factors and citations provided by the Institute of Scientific Information (ISI), and the journal list published in the Ergonomics Abstracts. Three groups of journals were distinguished. The "ergonomics journals" focus exclusively on ergonomics or human factors. The "related journals" focus on other disciplines than ergonomics or human factors, but regularly publish ergonomics/human factors papers. The "basic journals" focus on other technical, medical or social sciences than ergonomics, but are important for the development of ergonomics/human factors. Journal quality was rated using a maximum of four categories: top quality (A-level), high quality (B-level), good quality (C-level)) and professional (P-level). The above methods were applied to develop journal ratings for the year 2003. A total of 24 'ergonomics journals', 58 'related journals' and 142 'basic journals' were classified.impact factor;rating;scientific journals
An assessment system for rating scientific journals in the field of ergonomics and human factors
A method for selecting and rating scientific and professional journals representing the discipline of ergonomics and human factors is proposed. The method is based upon the journal list, impact factors and citations provided by the Institute of Scientific Information (ISI), and the journal list published in the Ergonomics Abstracts. Three groups of journals were distinguished. The "ergonomics journals" focus exclusively on ergonomics or human factors. The "related journals" focus on other disciplines than ergonomics or human factors, but regularly publish ergonomics/human factors papers. The "basic journals" focus on other technical, medical or social sciences than ergonomics, but are important for the development of ergonomics/human factors. Journal quality was rated using a maximum of four categories: top quality (A-level), high quality (B-level), good quality (C-level)) and professional (P-level). The above methods were applied to develop journal ratings for the year 2003. A total of 24 'ergonomics journals', 58 'related journals' and 142 'basic journals' were classified
The Three-Nucleon System Near the N-d Threshold
The three-nucleon system is studied at energies a few hundred keV above the
N-d threshold. Measurements of the tensor analyzing powers and
for p-d elastic scattering at keV are presented
together with the corresponding theoretical predictions. The calculations are
extended to very low energies since they are useful for extracting the p-d
scattering lengths from the experimental data. The interaction considered here
is the Argonne V18 potential plus the Urbana three-nucleon potential. The
calculation of the asymptotic D- to S-state ratio for H and He, for
which recent experimental results are available, is also presented.Comment: Latex, 11 pages, 2 figures, to be published in Phy.Lett.
Human sensitivity to gearshift loads
This paper describes an investigation of the ability of humans to distinguish different levels of gearlever load. A test rig with a forward-backward moving gearshift lever was constructed using the typical interior dimensions of European B segment automobiles. The rig used a system of weights and pulleys to provide a load which could be varied in steps of 1%. Four reference loads were chosen which were considered representative of automotive gearshift operation: 0.5, 1.0, 2.0 and 5.0 kg. Twenty subjects took part in the study. Using a variation on the psychophysical method of limits, the subjects were asked to respond whether a test load was heavier or lighter
than a reference load. The Weber Fraction was found to decrease monotonically from a value of 0.036 for the 0.5 kg reference load to a value of 0.029 at the 5.0 kg reference load. The average value across all reference loads was 0.032. Measurements of the gearshift force made by means of a knob containing a load cell suggested that the variation in the measured Weber Fraction might be attributable to the time behaviour of the force exchanged between the human subject and the control surface
Recoil Ranges of Nuclei Produced in Proton-Induced Reactions
This work was supported by National Science Foundation Grant PHY 76-84033 and Indiana Universit
Precision Measurements of d(d,p)t and d(d,n)^3He Total Cross Sections at Big-Bang Nucleosynthesis Energies
Recent Wilkinson Microwave Anisotropy Probe (WMAP) measurements have
determined the baryon density of the Universe with a precision of
about 4%. With tightly constrained, comparisons of Big Bang
Nucleosynthesis (BBN) abundance predictions to primordial abundance
observations can be made and used to test BBN models and/or to further
constrain abundances of isotopes with weak observational limits. To push the
limits and improve constraints on BBN models, uncertainties in key nuclear
reaction rates must be minimized. To this end, we made new precise measurements
of the d(d,p)t and d(d,n)^3He total cross sections at lab energies from 110 keV
to 650 keV.
A complete fit was performed in energy and angle to both angular distribution
and normalization data for both reactions simultaneously. By including
parameters for experimental variables in the fit, error correlations between
detectors, reactions, and reaction energies were accurately tabulated by
computational methods. With uncertainties around 2% +/- 1% scale error, these
new measurements significantly improve on the existing data set. At relevant
temperatures, using the data of the present work, both reaction rates are found
to be about 7% higher than those in the widely used Nuclear Astrophysics
Compilation of Reaction Rates (NACRE). These data will thus lead not only to
reduced uncertainties, but also to modifications in the BBN abundance
predictions.Comment: 15 pages, 11 figures, minor editorial change
Evidence for Three Nucleon Force Effects in p-d Elastic Scattering
A new measurement of the p-d differential cross section at Ep= 1 MeV has been
performed. These new data and older data sets at energies below the deuteron
breakup are compared to calculations using the two-nucleon Argonne v18 and the
three-nucleon Urbana IX potentials. A quantitative estimate of the capability
of these interactions to describe the data is given in terms of a chi^2
analysis. The chi^2 per datum drastically improves when the three-nucleon
interaction is included in the Hamiltonian.Comment: 13 pages, 5 figures, to be published in Phys. Rev.
Intermediate-mass-fragment Production in the Reaction of 200 MeV 3-He with Ag
This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440
Photoneutron reaction cross section measurements on 94Mo and 90Zr relevant to the p-process nucleosynthesis
The photodisintegration cross sections for the 94Mo({\gamma},n) and
90Zr({\gamma},n) reactions have been experimentally investigated with
quasi-monochromatic photon beams at the High Intensity {\gamma}-ray Source
(HI{\gamma}S) facility of the Triangle Universities Nuclear Laboratory (TUNL).
The energy dependence of the photoneutron reaction cross sections was measured
with high precision from the respective neutron emission thresholds up to 13.5
MeV. These measurements contribute to a broader investigation of nuclear
reactions relevant to the understanding of the p-process nucleosynthesis. The
results are compared with the predictions of Hauser-Feshbach statistical model
calculations using two different models for the dipole {\gamma}-ray strength
function. The resulting 94Mo({\gamma},n) and 90Zr({\gamma},n) photoneutron
stellar reaction rates as a function of temperature in the typical range of
interest for the p-process nucleosynthesis show how sensitive the photoneutron
stellar reaction rate can be to the experimental data in the vicinity of the
neutron threshold
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