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1 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
2 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
3 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
4 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
5 Transition in the fractal geometry of Arctic melt pondsDuring the Arctic melt season, the sea ice surface undergoes a remarkable transformation from vast expanses of snow covered ice to complex mosaics of ice and melt ponds. Sea ice albedo, a key parameter in climate modeling, is determined by the complex evolution of melt pond configurations. In fact, ...2012-01-01
6 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
7 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
8 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
9 Stress gradient balance layers and scale hierarchies in wall-bounded turbulent flowsSteady Couette and pressure-driven turbulent channel flows have large regions in which the gradients of the viscous and Reynolds stresses are approximately in balance (stress gradient balance regions). In the case of Couette flow, this region occupies the entire channel. Moreover, the relevant featu...Couette flow; Stress gradient balance; Reynolds stress; Turbulent channel flow2005
10 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
11 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
12 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
13 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
14 Statistical mechanics of conducting phase transitionsThe critical behavior of the effective conductivity o* of the random resistor network in Zd, near its percolation threshold, is considered. The network has bonds assigned the conductivities 1 and E >_0 in the volume fractions p and 1 -p. Motivated by the statistical mechanics of an Ising ferromagn...Resistor; Ising; Ferromagnet1995
15 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
16 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
17 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
18 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
19 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
20 Sea ice studies in the Weddell Sea aboard USCGC Polar SeaOur purpose was to investigate several of the characteristics of Weddell Sea pack ice that may affect the relative roles of dynamics and thermodynamics of pack ice development in this region. The total pack ice production and the movement of pack ice from its source area in the Weddell Sea is part...Floes.; Salinity; Formation1980
21 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
22 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
23 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
24 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
25 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
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