3,230 research outputs found
Analysis of the Economic Effects of Requiring Post-harvest Processing for Raw Oysters
oysters, post-harvest processing, hydrostatic pressure, cool pasteurization, GIS, Agricultural and Food Policy, Food Consumption/Nutrition/Food Safety, L510, Q180, Q220,
Food Safety Audits, Plant Characteristics, and Food Safety Technology Use in Meat and Poultry Plants
Food safety technology can increase a company’s capacity to prevent a foodborne contamination. A food safety audit—a quality control tool in which an auditor observes whether a plant’s processing practices and technologies are compatible with good food safety practices—can indicate how effectively food safety technology is being used. Fast food restaurants, grocery stores, and other major customers of meat and poultry processing plants conduct their own audits or hire auditors to assess the soundness of a plant’s processing operation. Meat and poultry plants can also audit themselves as a way to help maintain process control. In this report, we document the extent of food safety audits in meat and poultry processing plants. We also examine the associations between the use of audits and plant size, firm structure, and food safety technology use. Results show that larger plants, plants subject to food safety audits, and plants that are part of a multiplant firm use more food safety technology than other plants. Plants subject to both plant-hired and customer-hired audits had greater technology use than single (plant- or customer-hired) audit plants.Meat and poultry processing, safety standards, product recalls, food safety technology, food safety audits, Agribusiness, Food Consumption/Nutrition/Food Safety, Industrial Organization, Livestock Production/Industries,
Ultracold bosons in disordered superlattices: Mott-insulators induced by tunneling
We analyse the phase diagram of ultra-cold bosons in a one-dimensional
superlattice potential with disorder using the time evolving block decimation
algorithm for infinite sized systems (iTEBD). For degenerate potential energies
within the unit cell of the superlattice loophole-shaped insulating phases with
non-integer filling emerge with a particle-hole gap proportional to the boson
hopping. Adding a small amount of disorder destroys this gap. For not too large
disorder the loophole Mott regions detach from the axis of vanishing hopping
giving rise to insulating islands. Thus the system shows a transition from a
compressible Bose-glass to a Mott-insulating phase with increasing hopping
amplitude. We present a straight forward effective model for the dynamics
within a unit cell which provides a simple explanation for the emergence of
Mott-insulating islands. In particular it gives rather accurate predictions for
the inner critical point of the Bose-glass to Mott-insulator transition
EXIT OF MEAT SLAUGHTER PLANTS DURING IMPLEMENTATION OF THE PR/HACCP REGULATIONS
Implementation of the Pathogen Reduction and Hazard Analysis and Critical Control Points (PR/HACCP) regulations has occurred across all U.S. meat and poultry plants. A probit model is estimated to determine which factors have affected the probability of red meat slaughter plant exit during implementation of the regulations. While controlling for plant-level, company-level, regional-level, and supply conditions that may affect the probability of plant exit, smaller plants are found to exhibit a much greater probability of exit than larger plants. Other factors affecting plant exit include plant age, market share relative to the degree of market concentration, regional entry rates, and state-level wage rates.Agribusiness,
PLANT ENTRY AND EXIT FROM THE MEATPACKING INDUSTRY DURING PATHOGEN REDUCTION AND HACCP IMPLEMENTATION
Implementation of the Pathogen Reduction and Hazard Analysis and Critical Control Points (PR/HACCP) regulations has now occurred across all U.S. meat and poultry plants. Using databases of plants under federal inspection, we estimate a probit model to determine which factors have affected the probability of exit of meat slaughtering plants during implementation of the regulations.Industrial Organization, Livestock Production/Industries,
The Relationship Between Body Composition and Baseball Performance in Division II Baseball Players
Please view abstract in the attached PDF file
Particle number conservation in quantum many-body simulations with matrix product operators
Incorporating conservation laws explicitly into matrix product states (MPS)
has proven to make numerical simulations of quantum many-body systems much less
resources consuming. We will discuss here, to what extent this concept can be
used in simulation where the dynamically evolving entities are matrix product
operators (MPO). Quite counter-intuitively the expectation of gaining in speed
by sacrificing information about all but a single symmetry sector is not in all
cases fulfilled. It turns out that in this case often the entanglement imposed
by the global constraint of fixed particle number is the limiting factor.Comment: minor changes, 18 pages, 5 figure
Dynamics and evaporation of defects in Mott-insulating clusters of boson pairs
Repulsively bound pairs of particles in a lattice governed by the
Bose-Hubbard model can form stable incompressible clusters of dimers
corresponding to finite-size n=2 Mott insulators. Here we study the dynamics of
hole defects in such clusters corresponding to unpaired particles which can
resonantly tunnel out of the cluster into the lattice vacuum. Due to bosonic
statistics, the unpaired particles have different effective mass inside and
outside the cluster, and "evaporation" of hole defects from the cluster
boundaries is possible only when their quasi-momenta are within a certain
transmission range. We show that quasi-thermalization of hole defects occurs in
the presence of catalyzing particle defects which thereby purify the Mott
insulating clusters. We study the dynamics of one-dimensional system using
analytical techniques and numerically exact t-DMRG simulations. We derive an
effective strong-interaction model that enables simulations of the system
dynamics for much longer times. We also discuss a more general case of two
bosonic species which reduces to the fermionic Hubbard model in the strong
interaction limit.Comment: 12 pages, 10 figures, minor update
Prediction with Expert Advice under Discounted Loss
We study prediction with expert advice in the setting where the losses are
accumulated with some discounting---the impact of old losses may gradually
vanish. We generalize the Aggregating Algorithm and the Aggregating Algorithm
for Regression to this case, propose a suitable new variant of exponential
weights algorithm, and prove respective loss bounds.Comment: 26 pages; expanded (2 remarks -> theorems), some misprints correcte
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