504 research outputs found
A REVIEW OF CONTRIBUTIONS TO THE WESTERN JOURNAL OF AGRICULTURAL ECONOMICS: 1977-81
In this study a complete survey of all WJAE articles was conducted. The 158 titles that have appeared in the WJAE as of December 1981 are categorized by institutional category, authorship affiliation, and subject category. These results are compared to similar studies concerning the SJAE and AJAE. Our findings indicate that the WJAE has a broad range of contributors and is not dominated by any one institution, author, or group of authors. We feel that these and other interesting results are of general interest to all WJAE readers.Teaching/Communication/Extension/Profession,
A three-dimensional analysis of marine radar images for the determination of ocean wave directionality and surface currents
A series of spatial wave images recorded by a conventional marine radar is analyzed to determine the three-dimensional E(kx, ky, ω) spectrum. In the absence of a surface current the spectral energy in this three-dimensional wave number frequency space will lie on a shell defined by the dispersion relationship. Any deviation from the expected dispersion relationship can be interpreted as being due to a current induced Doppler shift of the wave frequency. A least squares curve fitting technique is used to determine the surface current required to account for the observed Doppler shift. A comparison of the radar determined spectra and surface currents with ground truth data indicates that the radar system and analysis technique produces results consistent with conventional instrumentation
The enclosure method for the heat equation
This paper shows how the enclosure method which was originally introduced for
elliptic equations can be applied to inverse initial boundary value problems
for parabolic equations. For the purpose a prototype of inverse initial
boundary value problems whose governing equation is the heat equation is
considered. An explicit method to extract an approximation of the value of the
support function at a given direction of unknown discontinuity embedded in a
heat conductive body from the temperature for a suitable heat flux on the
lateral boundary for a fixed observation time is given.Comment: 12pages. This is the final versio
Null sets of harmonic measure on NTA domains: Lipschitz approximation revisited
We show the David-Jerison construction of big pieces of Lipschitz graphs
inside a corkscrew domain does not require its surface measure be upper Ahlfors
regular. Thus we can study absolute continuity of harmonic measure and surface
measure on NTA domains of locally finite perimeter using Lipschitz
approximations. A partial analogue of the F. and M. Riesz Theorem for simply
connected planar domains is obtained for NTA domains in space. As a consequence
every Wolff snowflake has infinite surface measure.Comment: 22 pages, 6 figure
Boundary Asymptotic Analysis for an Incompressible Viscous Flow: Navier Wall Laws
We consider a new way of establishing Navier wall laws. Considering a bounded
domain of R N , N=2,3, surrounded by a thin layer ,
along a part 2 of its boundary , we consider a
Navier-Stokes flow in with
Reynolds' number of order 1/ in . Using
-convergence arguments, we describe the asymptotic behaviour of the
solution of this problem and get a general Navier law involving a matrix of
Borel measures having the same support contained in the interface 2. We
then consider two special cases where we characterize this matrix of measures.
As a further application, we consider an optimal control problem within this
context
Extraction of electromagnetic neutron form factors through inclusive and exclusive polarized electron scattering on polarized 3He target
Inclusive 3He(e,e') and exclusive 3He(e,e'n) processes with polarized
electrons and 3He have been theoretically analyzed and values for the magnetic
and electric neutron form factors have been extracted. In both cases the form
factor values agree well with the ones extracted from processes on the
deuteron. Our results are based on Faddeev solutions, modern NN forces and
partially on the incorporation of mesonic exchange currents.Comment: 28 pages, 29 Postscript figure
Phase transition and correlation decay in Coupled Map Lattices
For a Coupled Map Lattice with a specific strong coupling emulating
Stavskaya's probabilistic cellular automata, we prove the existence of a phase
transition using a Peierls argument, and exponential convergence to the
invariant measures for a wide class of initial states using a technique of
decoupling originally developed for weak coupling. This implies the exponential
decay, in space and in time, of the correlation functions of the invariant
measures
Global Solutions of the Navier-Stokes Equations for Isentropic Flow with Large External Potential Force
We prove the global-in-time existence of weak solutions to the Navier-Stokes
equations of compressible isentropic flow in three space dimensions with
adiabatic exponent . Initial data and solutions are small in
around a non-constant steady state with densities being positive and
essentially bounded. No smallness assumption is imposed on the external forces
when . A great deal of information about partial regularity and
large-time behavior is obtained.Comment: 17 page
- …