76,256 research outputs found
Full employment maintenance in the private sector
Operationally, full employment can be accomplished by applying modern computer capabilities, game and decision concepts, and communication feedback possibilities, rather than accepted economic tools, to the problem of assuring invariant full employment. The government must provide positive direction to individual firms concerning the net number of employees that each firm must hire or refrain from hiring to assure national full employment. To preserve free enterprise and the decision making power of the individual manager, this direction must be based on each private firm's own numerical employment projections
High dispersion observations of Venus during 1972. The CO2 band at 7820 angstrom
Photographic plates of Venus which show the spectrum of the carbon dioxide band at 7820A were obtained at Table Mountain Observatory in September-October 1972. These spectra showed a semi-regular 4-day variation in the CO2 abundance over the disk of the planet. Evidence for temporal variations in the rotational temperature of this band and temperature variations over the disk was found. The two quantities, CO2 abundance and temperature, do not show any obvious relationship; however, an increase in the temperature usually is accompanied by a decrease in the abundance of CO2. The average temperature, found from a curve of growth analysis assuming a constant CO2 line of width, is 249 plus or minus 1.4 K (one standard deviation)
Probing the Almeida-Thouless line away from the mean-field model
Results of Monte Carlo simulations of the one-dimensional long-range Ising
spin glass with power-law interactions in the presence of a (random) field are
presented. By tuning the exponent of the power-law interactions, we are able to
scan the full range of possible behaviors from the infinite-range
(Sherrington-Kirkpatrick) model to the short-range model. A finite-size scaling
analysis of the correlation length indicates that the Almeida-Thouless line
does not occur in the region with non-mean-field critical behavior in zero
field. However, there is evidence that an Almeida-Thouless line does occur in
the mean-field region.Comment: 5 pages, 3 figures, 3 table
Adaptive polarization separation
A broadband adaptively controlled polarization separation network is discussed. Two transmitted signals vertically and horizontally polarized are received as elliptically polarized signals. If there is any vertical polarization on the other signal the separation network provides two signals. The separation is done automatically by the use of two sets of crosscouplers which couple a single line to the other line to complete the polarization decoupling operation
Predicting Avian Influenza Co-Infection with H5N1 and H9N2 in Northern Egypt.
Human outbreaks with avian influenza have been, so far, constrained by poor viral adaptation to non-avian hosts. This could be overcome via co-infection, whereby two strains share genetic material, allowing new hybrid strains to emerge. Identifying areas where co-infection is most likely can help target spaces for increased surveillance. Ecological niche modeling using remotely-sensed data can be used for this purpose. H5N1 and H9N2 influenza subtypes are endemic in Egyptian poultry. From 2006 to 2015, over 20,000 poultry and wild birds were tested at farms and live bird markets. Using ecological niche modeling we identified environmental, behavioral, and population characteristics of H5N1 and H9N2 niches within Egypt. Niches differed markedly by subtype. The subtype niches were combined to model co-infection potential with known occurrences used for validation. The distance to live bird markets was a strong predictor of co-infection. Using only single-subtype influenza outbreaks and publicly available ecological data, we identified areas of co-infection potential with high accuracy (area under the receiver operating characteristic (ROC) curve (AUC) 0.991)
Monte Carlo Simulations of Spin Glasses at Low Temperatures
We report the results of Monte Carlo simulations on several spin glass models
at low temperatures. By using the parallel tempering (Exchange Monte Carlo)
technique we are able to equilibrate down to low temperatures, for moderate
sizes, and hence the data should not be affected by critical fluctuations. Our
results for short range models are consistent with a picture proposed earlier
that there are large scale excitations which cost only a finite energy in the
thermodynamic limit, and these excitations have a surface whose fractal
dimension is less than the space dimension. For the infinite range Viana-Bray
model, our results obtained for a similar number of spins are consistent with
standard replica symmetry breaking.Comment: 12 pages, 21 postscript figures included. Replaced by published
versio
Integrability and maximally helicity violating diagrams in n=4 supersymmetric yang-mills theory.
We apply maximally helicity violating (MHV) diagrams to the derivation of the one-loop dilatation operator of N=4 supersymmetric Yang-Mills theory in the SO(6) sector. We find that in this approach the calculation reduces to the evaluation of a single MHV diagram in dimensional regularization. This provides the first application of MHV diagrams to an off-shell quantity. We also discuss other applications of the method and future directions
Planetary isophotes as a clue to aerosol characteristics
A study was conducted to see how much information could be extracted from the Mariner 9 Mars isophotes taken at a phase angle of approximately 60 deg. It was found that the Minnaert functions and both isotropic and Rayleigh scattering could easily be ruled out, and that it was essential to use forward-peaked phase functions, which were computed from Mie theory. Isophotes similar to those observed assuming a semi-infinite dust cloud with a considerable variation in particle properties and size distribution could be obtained, so long as the ratio of the multiply- to singly-scattered light was held within certain limits. These conditions are met by micron-sized, moderatly absorbing mineral grains whose mean size should not be much larger than a micron. It was also found that a dust cloud of finite optical thickness bounded from below by a Lambert ground would fit the isophote data
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