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CreatorTitleDescriptionSubjectDate
1 Arbitrarily slow approach to limiting behaviorABSTRACT. Let f(k, t): RN x [0, oo) -- R be jointly continuous in k and t, with lim(t)--(oo) f(k, t) = F(k) discontinuous for a dense set of k's. It is proven that there exists a dense set T of k's such that, for k e T , |f(k, t) - F(k)| approaches 0 arbitrarily slowly, i.e., roughly speaking, more ...Random; Conductivity; Diffusion1991
2 Bounds on the complex permittivity of matrix-particle compositesThe complex effective dielectric constant E* of matrix-particle composites is considered. Such composites consist of separated inclusions of material of type one embedded in a matrix of material of type two. The analytic continuation method is used to derive a series of bounds which incorporate a n...Random; Parameters; Continuation1995
3 Bounds on the complex permittivity of sea iceAn analytic method for obtaining bounds on effective properties of composites is applied to the complex permittivity e* of sea ice. The sea ice is assumed to be a two-component random medium consisting of pure ice of permittivity e1, and brine of permittivity e2. The method exploits the properties ...Brine; Properties; Geometry1995
4 Brine percolation and the transport properties of sea iceSea ice is distinguished from many other porous composites, such as sandstones or bone, in that its microstructure and bulk material properties can vary dramatically over a small temperature range. For brine-volume fractions below a critical value of about 5%, which corresponds to a critical tempera...Brine volume; Percolation theory; Connectedness properties2001
5 Broad spectral, interdisciplinary investigation of the electromagnetic properties of sea iceThis paper highlights the interrelationship of research completed by a team of investigators and presented in the several individual papers comprising this Special Section on the Office of Naval Research (ONR), Arlington, VA, Sponsored Sea Ice Electromagnetics Accelerated Research Initiative (ARI).Scattering; Radiation; EM1998
6 BTS1 encodes a geranylgeranyl diphosphate synthase in Saccharomyces cerevisiaeProtein prenylation utilizes different types of isoprenoids groups, namely farnesyl and geranylgeranyl, to modify proteins. These lipophilic moieties attach to carboxyl-terminal cysteine residues to promote the association of soluble proteins to membranes. Most prenylated proteins are geranylgeranyl...Amino Acid Sequence; Cloning, Molecular; Gene Expression1995-09-15
7 Classical transport in quasiperiodic mediaAbstract. Classical transport coefficients such as the effective conductivity or diffusivity of a quasiperiodic medium were observed [1] to depend discontinuously on the frequencies of the quasiperiodicity. For example, for a one-dimensional medium with a potential V(x) = cosx + coskx , the effecti...Transport; Diffusion; Random1991
8 Climate change and the mathematics of transport in sea iceAs the boundary layer between the ocean and atmosphere in the polar regions, sea ice is a critical component of the global climate system. As temperatures on Earth have warmed, the Arctic sea ice pack in particular has exhibited a dramatic decline in its summer extent. Indeed, the polar sea-ice pack...Polar ice; Fluid flow; Complex permittivity2009
9 Composite microstructures and climate changeDevelop mathematical models to better understand the changes in sea ice as it pertains to global climate. Compare Diffusion Limited Aggregates (DLA) and Electrorheological (ER) fluids to sea ice microstructures.Composite microstructures; Climate change; Effect on climate; Trapeze Interactive Poster2010-03-15
10 Convexity and exponent inequalities for conduction near percolationThe bulk conductivity o*(p) of the bond lattice in Zd with a fraction p of conducting bonds is analyzed. Assuming a hierarchical node-link-blob (NLB) model of the conducting backbone, it is shown that o*(p) (for this model) is convex in p near the percolation threshold pc, and that its critical expo...Lattice; Conductivity; Model1990
11 Convexity in random resistor networksThe bulk conductivity o*(p) of the bond lattice in Zd is considered, where the conductivity of the bonds is either 1 with probability p or e > 0 with probability 1 - p. Rigorous and non-rigorous results demonstrating convexity of o*(p) near the percolation threshold pc are presented.Conductivity; Bond lattice; Critical exponent t1989
12 Critical behavior of transport in lattice and continuum percolation modelsIt has been observed that the critical exponents of transport in the continuum, such as in the Swiss cheese and random checkerboard models, can exhibit nonuniversal behavior, with values different than the lattice case. Nevertheless, it is shown here that the transport exponents for both lattice a...Ising model; Magnetization; Scaling1997
13 Critical behavior of transport in percolation-controlled smart compositesThe electrical transport properties of many smart composites and other technologically important materials are dominated by the connectedness, or percolation properties of a particular component. Predicting the critical behavior of such media near their percolation threshold, where one typically obt...Matrix-particle composites1997
14 Electrical transport in high contrast composite materialsA broad range of problems in the physics of materials involve highly disordered media whose effective behavior depends critically on the connectedness, or percolation properties of a particular component. Examples include smart materials such as piezoresistors and thermistors, smart insulators, rada...1997
15 Exact result for the effective conductivity of a continuum percolation modelA random two-dimensional checkerboard of squares of conductivities 1 and 8 in proportions p and 1 - p is considered. Classical duality implies that the effective conductivity obeys o* = V8 at p = 1/2. It is rigorously found here that to leading order as 8--0, this exact result holds for all p in the...Particles; Matrix; Checkerboard1994
16 Forward electromagnetic scattering models for sea iceRecent advances in forward modeling of the electromagnetic scattering properties of sea ice are presented. In particular, the principal results include the following: 1) approximate calculations of electromagnetic scattering from multilayer random media with rough interfaces, based on the distorte...Polar ice; Electromagnetic scattering; Electromagnetic scattering forward problems; Multilayer random media; Dielectric materials; Nonhomogeneous media; Remote sensing1998
17 Inverse electromagnetic scattering models for sea iceInverse scattering algorithms for reconstructing the physical properties of sea ice from scattered electromagnetic field data are presented. The development of these algorithms has advanced the theory of remote sensing, particularly in the microwave region, and has the potential to form the basis f...Polar ice; Electromagnetic scattering; Electromagnetic scattering inverse problems; Multilayer random media; Dielectric materials; Nonhomogeneous media; Remote sensing1998
18 Laboratory measurements of sea ice: connections to microwave remote sensingThe connections between laboratory measurements and remote-sensing observations of sea ice are explored. The focus of this paper is on thin ice, which is more easily simulated in a laboratory environment. We summarize results of C-band scatterometer measurements and discuss how they may help in the ...Electromagnetic; Radar; Backscatter1998
19 The lsing model and critical behavior of transport in binary composite mediaWe present a general theory for critical behavior of transport in binary composite media. The theory holds for lattice and continuum percolation models in both the static case with real parameters and the quasi-static case (frequency dependent) with complex parameters. Through a direct, analytic cor...2012-01-01
20 Modeling of anisotropic electromagnetic reflection from sea iceThe contribution of brine layers to observed reflective anisotropy of sea ice at 100 MHz is quantitatively assessed, and a theoretical explanation for observed reflective anisotropy is proposed in terms of anisotropic electric flux penetration into the brine layers. The sea ice is assumed to be a st...Brine; Anisotropy; Polarization1981
21 Multiscale analysis of heat transfer in fully developed turbulent channel flowAn analysis is given for fully developed thermal transport through a wall-bounded turbulent fluid with constant heat flux supplied at the boundary. The analysis proceeds from the aver-aged heat equation and utilizes, as principal tools, various scaling considerations. The paper first provides an acc...Turbulant flow; Channel flow; Heat transfer; Multiscale analysis2005-12
22 Nash estimates and the asymptotic behavior of diffusionsIn order to analyze the asymptotic behavior of a particle diffusing in a drift field derived from a smooth bounded potential, we develop Nash-type a priori estimates on the transition density of the process. As an immediate consequence of the estimates, we find that for a rapidly decaying potential...Potentials; Transition; Divergence1988
23 Network model for fluid transport through sea iceThe flow of liquid through porous sea ice is a fundamental process affecting problems in polar biology, oceanography and geophysics. The geometry and connectedness of the pore microstructure of sea ice determine its fluid permeability, which depends strongly on temperature. Here we analyze a simple ...Fluid transport; Pipe network; Brine2006
24 Physical and structural characteristics of Weddell Sea pack iceRecent studies by CRREL researchers of the dynamics and thermodynamics of sea ice in the Antarctic have included investigations of the physical and structural properties of pack ice in the Weddell Sea. The formation of pack ice and its subsequent movement from source areas in the Weddell Sea is part...Salinity; Brine; Frazil1987
25 Properties of the mean momentum balance in turbulent boundary layer, pipe and channel flowsThe properties of the mean momentum balance in turbulent boundary layer, pipe and channel flows are explored both experimentally and theoretically. Available high-quality data reveal a dynamically relevant four-layer description that is a departure from the mean profile four-layer description tradit...Turbulent channel flow; Pipe flow; Reynolds stress2005
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