55,025 research outputs found
Recommended from our members
Coated Feedstock for Fabrication of Ceramic Parts by CAM-LEM
In laminated object manufacturing of ceramic components, lamination is one of the most
important materials issues. Good lamination ensures monolithic component after firing.
Otherwise, lamination defects that inevitably will occur in the parts will affect the
properties of ceramic components. Adhesive (both liquid and non-liquid) lamination
processes were developed for the cut-then-stack (CAM-LEM) procedure. The non-liquid
adhesive lamination is discussed in detail.Mechanical Engineerin
TROPHIC PORTFOLIOS IN MARINE FISHERIES: A STEP TOWARDS ECOSYSTEM MANAGEMENT
Marine ecologists warn that humans are "fishing down marine food webs." To explore the economic implications of this phenomenon, this paper applies portfolio theory to aggregate fisheries data. It poses two definitions of a sustainable mean-variance catch frontier. It computes a mean-variance frontier for catch using UNFAO historical fisheries data. Finally, the paper discusses the historical trend in inefficiency.Environmental Economics and Policy, Resource /Energy Economics and Policy,
Quantum Confinement Induced Metal-Insulator Transition in Strongly Correlated Quantum Wells of SrVO Superlattice
Dynamical mean-field theory (DMFT) has been employed in conjunction with
density functional theory (DFT+DMFT) to investigate the metal-insulator
transition (MIT) of strongly correlated electrons due to quantum
confinement. We shed new light on the microscopic mechanism of the MIT and
previously reported anomalous subband mass enhancement, both of which arise as
a direct consequence of the quantization of V states in the SrVO
layers. We therefore show that quantum confinement can sensitively tune the
strength of electron correlations, leading the way to applying such approaches
in other correlated materials
Quantum imaging of spin states in optical lattices
We investigate imaging of the spatial spin distribution of atoms in optical
lattices using non-resonant light scattering. We demonstrate how scattering
spatially correlated light from the atoms can result in spin state images with
enhanced spatial resolution. Furthermore, we show how using spatially
correlated light can lead to direct measurement of the spatial correlations of
the atomic spin distribution
THE DYNAMICS OF FEEDER CATTLE MARKET RESPONSES TO CORN PRICE CHANGE
A feeder-calf price model is estimated which incorporates elements of break-even budget analysis, including estimates of placement weights, slaughter weights, ration cost, and feed-conversion rates. From this model, a corn price multiplier is calculated which quantifies the corn/feeder-calf price relationship. Because the multiplier includes information on cattle weight, feed conversion, and ration cost, it also provides insight into how feeding programs are altered in response to corn price changes. Changes in feeding programs which occur in response to corn price changes are illustrated with dynamic simulation based on weight, ration cost, and price models presented here.corn, corn price multiplier, dynamic simulation, feeder cattle, Demand and Price Analysis,
Predictions of the emergence of vaccine-resistant hepatitis B in The Gambia using a mathematical model
Vaccine escape variants of hepatitis B virus (HBV) have been identified world-wide. A mathematical model of HBV transmission is used to investigate the potential pattern of emergence of such variants. Attention is focused on The Gambia as a country with high quality epidemiological data, universal infant immunization and in which escape mutants after childhood infections have been observed. We predict that a variant cannot become dominant for at least 20 years from the start of vaccination, even when using a vaccine which affords no cross protection. The dominant factor responsible for this long time scale is the low rate of infectious contacts between infected and susceptible individuals (we estimate the basic reproduction number of hepatitis B in The Gambia to be 1·7). A variant strain that achieves high prevalence will also take many years to control, and it is questionable whether emergence will be identifiable by sero-surveillance until of high prevalence. The sensitivity of the model predictions to epidemiological and demographic factors is explored
Predictions of the emergence of vaccine-resistant hepatitis B in The Gambia using a mathematical model
Vaccine escape variants of hepatitis B virus (HBV) have been identified world-wide. A mathematical model of HBV transmission is used to investigate the potential pattern of emergence of such variants. Attention is focused on The Gambia as a country with high quality epidemiological data, universal infant immunization and in which escape mutants after childhood infections have been observed. We predict that a variant cannot become dominant for at least 20 years from the start of vaccination, even when using a vaccine which affords no cross protection. The dominant factor responsible for this long time scale is the low rate of infectious contacts between infected and susceptible individuals (we estimate the basic reproduction number of hepatitis B in The Gambia to be 1·7). A variant strain that achieves high prevalence will also take many years to control, and it is questionable whether emergence will be identifiable by sero-surveillance until of high prevalence. The sensitivity of the model predictions to epidemiological and demographic factors is explored
Top quark asymmetry from a non-Abelian horizontal symmetry
Motivated by the persistence of a large measured top quark forward-backward
asymmetry at the Tevatron, we examine a model of non-Abelian flavor gauge
symmetry. The exchange of the gauge bosons in the -channel can give a large
asymmetry due to the forward Rutherford scattering peak. We address generic
constraints on non-Abelian -channel physics models including flavor diagonal
resonances and potentially dangerous contributions to inclusive top pair cross
sections. We caution on the general difficulty of comparing theoretical
predictions for top quark signals to the existing experimental results due to
potentially important acceptance effects. The first signature at the Large
Hadron Collider can be a large inclusive top pair cross section, or like-sign
dilepton events, although the latter signal is much smaller than in Abelian
models. Deviations of the invariant mass distributions at the LHC will also be
promising signatures. A more direct consistency check of the Tevatron asymmetry
through the LHC asymmetry is more likely to be relevant at a later stage.Comment: 21 pages, 7 figure
- …