1,940 research outputs found
THE MARKET FOR E-COMMERCE SERVICES IN AGRICULTURE
We report results of a survey of 608 Ohio agribusinesses in 1999 and show them to be divided in their attitudes and acceptance of e-commerce. Half of the respondents report that their business has a web site, although many had taken a negative stance toward such a move. Nearly all say that the internet will significantly change their sector, and the majority of managers report that e-commerce has significantly affected the way they view their business.Marketing,
Free-space quantum key distribution
A working free-space quantum key distribution (QKD) system has been developed
and tested over a 205-m indoor optical path at Los Alamos National Laboratory
under fluorescent lighting conditions. Results show that free-space QKD can
provide secure real-time key distribution between parties who have a need to
communicate secretly.Comment: 5 pages, 2 figures, 2 tables. To be published in Physical review A on
or about 1 April 199
Universality relations in non-solvable quantum spin chains
We prove the exact relations between the critical exponents and the
susceptibility, implied by the Haldane Luttinger liquid conjecture, for a
generic lattice fermionic model or a quantum spin chain with short range weak
interaction. The validity of such relations was only checked in some special
solvable models, but there was up to now no proof of their validity in
non-solvable models
Effect of Cooked Soybeans and Type of Housing on Growth Performance and Carcass Chracteristics of Swine
Previous research conducted at the Southeast South Dakota Experiment Farm had shown very little difference in rate of gain of growing pigs housed in to tally confined or in open-front buildings . However, approximately 9% less feed was required when pigs were housed in the confinement buildings . The present experiment was conducted to obtain further information on the effect of cooked soybeans in diets for growing pigs wh en housed in a controlled environment confinement building or an open-front building with waterers and feeders in an outside concrete lot
Cooked and Raw Soybeans as Supplemental Protein Sources for Growing-Finishing Swine
The objective of the experiment reported herein was to evaluate the use of cooked and raw soybeans in diets for finishing swine
Laser beam filamentation in fractal aggregates
We investigate filamentation of a cw laser beam in soft matter such as
colloidal suspensions and fractal gels. The process, driven by
electrostriction, is strongly affected by material properties, which are taken
into account via the static structure factor, and have impact on the statistics
of the light filaments.Comment: 4 pages, 5 figures. Revised version with corrected figure 5. To be
published in Phys. Rev. Let
Bosonization of the Low Energy Excitations of Fermi Liquids
We bosonize the low energy excitations of Fermi Liquids in any number of
dimensions in the limit of long wavelengths. The bosons are coherent
superposition of electron-hole pairs and are related with the displacement of
the Fermi Surface in some arbitrary direction. A coherent-state path integral
for the bosonized theory is derived and it is shown to represent histories of
the shape of the Fermi Surface. The Landau equation for the sound waves is
shown to be exact in the semiclassical approximation for the bosons.Comment: 10 pages, RevteX, P-93-03-027 (UIUC
Correlation functions for a two-dimensional electron system with bosonic interactions and a square Fermi surface
We calculate zero-temperature correlation functions for a model of 2D
interacting electrons with short-range interactions and a square Fermi surface.
The model was arrived at by mapping electronic states near a square Fermi
surface with Hubbard-like interactions onto one-dimensional quantum chains,
retaining terms which can be written in terms of bosonic density operators.
Interactions between orthogonal chains, corresponding to orthogonal faces of
the square Fermi surface, are neglected. The correlation functions become sums
of Luttinger-type correlation functions due to the bosonic model. However, the
correlation function exponents differ in form from those of the Luttinger
model. As a consequence, the simple scaling relations found to exist between
the Luttinger model exponents, do not carry over to the leading exponents of
our model. We find that for repulsive effective interactions, charge-density
wave/spin-density wave instabilities are dominant. We do not consider d-wave
instabilities here.Comment: 12 pages, no figures; to be published in Physical Review
Method of isolating an analyte using a solid phase extraction medium
A functionalized macroporous poly(styrene divinylbenzene) particle comprises at least one ionic functional group covalently bonded thereto, the functionalized particle having sorptive capability towards an analyte, said functional group being present in the range of 0.1 to 2.5 milliequivalents per gram of poly(styrene divinylbenzene). The functionalized particles can be used in a packed column or enmeshed in a nonwoven web for utility in solid phase extraction applications
Non-linear Characteristics of Luttinger Liquids and Gated Hall Bars
Non-linear current voltage characteristics of a disordered Luttinger liquid
are calculated using a perturbative formalism. One finds non-universal power
law characteristics of the form which is valid
both in the superfluid phase when is small and also in the insulator phase
when is large. Mesoscopic voltage fluctuations are also calculated. One
finds \Var(\Delta V) \sim I^{4\tilde{g}-3}. Both the characteristic
and the voltage fluctuations exhibit universal power law behavior at the
superfluid insulator transition where \tilde{g}=\tot. The possible
application of these results to the non-linear transport properties of gated
Hall bars is discussed.Comment: 8 pages. 4 uuencoded tiff figures available upon request to
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