1,499 research outputs found
Spray drying costs in low-volume milk plants
Since World War II several developments have given impetus to a shift from marketing farm-separated cream to marketing whole milk. The increased consumer demand for nonfat dry milk, the government price-support program, the introduction of drying equipment small enough to make drying feasible for small plants, and farmers preferences have all had a share in inducing plants to shift from a butter manufacturing operation to a butter-powder operation.https://lib.dr.iastate.edu/specialreports/1016/thumbnail.jp
Manufacturing costs: whole milk creameries
Dairying in Iowa has been an essential part of most farm operations. The skim milk resulting from farm separation of the cream has been a useful supplement to com in the swine feeding operations which constitute the most important single phase of Iowa agriculture. Because of this relationship between dairying and hog farming, the dairy processing industry in Iowa has been based primarily on one product, butter, and most of this has been manufactured in creameries receiving only farm-separated cream. Many of these creameries were established 50-60 years ago when the roads and transportation facilities of the time dictated the need for many local plants which tended to remain small. Over the years this system of dairy marketing has persisted in Iowa. In other important dairy sections of the United States, there has been a trend to concentrate dairy processing in larger plants manufacturing a number of different products.https://lib.dr.iastate.edu/specialreports/1014/thumbnail.jp
Fluctuations of elastic interfaces in fluids: Theory and simulation
We study the dynamics of elastic interfaces-membranes-immersed in thermally
excited fluids. The work contains three components: the development of a
numerical method, a purely theoretical approach, and numerical simulation. In
developing a numerical method, we first discuss the dynamical coupling between
the interface and the surrounding fluids. An argument is then presented that
generalizes the single-relaxation time lattice-Boltzmann method for the
simulation of hydrodynamic interfaces to include the elastic properties of the
boundary. The implementation of the new method is outlined and it is tested by
simulating the static behavior of spherical bubbles and the dynamics of bending
waves. By means of the fluctuation-dissipation theorem we recover analytically
the equilibrium frequency power spectrum of thermally fluctuating membranes and
the correlation function of the excitations. Also, the non-equilibrium scaling
properties of the membrane roughening are deduced, leading us to formulate a
scaling law describing the interface growth, W^2(L,T)=L^3 g[t/L^(5/2)], where
W, L and T are the width of the interface, the linear size of the system and
the temperature respectively, and g is a scaling function. Finally, the
phenomenology of thermally fluctuating membranes is simulated and the frequency
power spectrum is recovered, confirming the decay of the correlation function
of the fluctuations. As a further numerical study of fluctuating elastic
interfaces, the non-equilibrium regime is reproduced by initializing the system
as an interface immersed in thermally pre-excited fluids.Comment: 15 pages, 11 figure
Hybrid quantum computation in quantum optics
We propose a hybrid quantum computing scheme where qubit degrees of freedom for computation are combined with quantum continuous variables for communication. In particular, universal two-qubit gates can be implemented deterministically through qubit-qubit communication, mediated by a continuous-variable bus mode (“qubus”), without direct interaction between the qubits and without any measurement of the qubus. The key ingredients are controlled rotations of the qubus and unconditional qubus displacements. The controlled rotations are realizable through typical atom-light interactions in quantum optics. For such interactions, our scheme is universal and works in any regime, including the limits of weak and strong nonlinearities
Integration of highly probabilistic sources into optical quantum architectures: perpetual quantum computation
In this paper we introduce a design for an optical topological cluster state
computer constructed exclusively from a single quantum component. Unlike
previous efforts we eliminate the need for on demand, high fidelity photon
sources and detectors and replace them with the same device utilised to create
photon/photon entanglement. This introduces highly probabilistic elements into
the optical architecture while maintaining complete specificity of the
structure and operation for a large scale computer. Photons in this system are
continually recycled back into the preparation network, allowing for a
arbitrarily deep 3D cluster to be prepared using a comparatively small number
of photonic qubits and consequently the elimination of high frequency,
deterministic photon sources.Comment: 19 pages, 13 Figs (2 Appendices with additional Figs.). Comments
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Domain Growth, Wetting and Scaling in Porous Media
The lattice Boltzmann (LB) method is used to study the kinetics of domain
growth of a binary fluid in a number of geometries modeling porous media.
Unlike the traditional methods which solve the Cahn-Hilliard equation, the LB
method correctly simulates fluid properties, phase segregation, interface
dynamics and wetting. Our results, based on lattice sizes of up to , do not show evidence to indicate the breakdown of late stage dynamical
scaling, and suggest that confinement of the fluid is the key to the slow
kinetics observed. Randomness of the pore structure appears unnecessary.Comment: 13 pages, latex, submitted to PR
Quantum cellular automata quantum computing with endohedral fullerenes
We present a scheme to perform universal quantum computation using global
addressing techniques as applied to a physical system of endohedrally doped
fullerenes. The system consists of an ABAB linear array of Group V endohedrally
doped fullerenes. Each molecule spin site consists of a nuclear spin coupled
via a Hyperfine interaction to an electron spin. The electron spin of each
molecule is in a quartet ground state . Neighboring molecular electron
spins are coupled via a magnetic dipole interaction. We find that an
all-electron construction of a quantum cellular automata is frustrated due to
the degeneracy of the electronic transitions. However, we can construct a
quantum celluar automata quantum computing architecture using these molecules
by encoding the quantum information on the nuclear spins while using the
electron spins as a local bus. We deduce the NMR and ESR pulses required to
execute the basic cellular automata operation and obtain a rough figure of
merit for the the number of gate operations per decoherence time. We find that
this figure of merit compares well with other physical quantum computer
proposals. We argue that the proposed architecture meets well the first four
DiVincenzo criteria and we outline various routes towards meeting the fifth
criteria: qubit readout.Comment: 16 pages, Latex, 5 figures, See http://planck.thphys.may.ie/QIPDDF/
submitted to Phys. Rev.
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