Design and development criteria for metal bellows

Experimental research describes fluid flow and the fluid-elastic mechanism causing bellows flow excitation, and aids in design of conventional bellows liner which suppresses flow-induced vibrations. Analytical models facilitate prediction of flow excitation occurrence and estimation of severity of bellows vibrations

FED CATTLE SPATIAL TRANSACTIONS PRICE RELATIONSHIPS

Delineation of geographic markets for fed cattle is essential in monitoring price behavior and determining geographic markets. This study uses transactions data from 28 U.S. fed cattle slaughter plants to determine the extent of the geographic market for fed cattle. Results indicate a national market for fed cattle with prices across most plants cointegrated. In addition, price discovery originates predominantly at plants located in Nebraska, and typically one-third of the total price adjustment to spatial integration occurs in one day.Cointegration, Relevant market, Spatial prices, Demand and Price Analysis, Livestock Production/Industries,

DETERMINANTS OF FEEDER CATTLE PRICE-WEIGHT SLIDES

Feeder cattle price-weight slides are analyzed using transactions data on 46,123 pens of feeder cattle over a 10-year period. Fed cattle futures prices and corn prices are important determinants of price-weight slides. Cattle producers can use this information when making sell timing decision, purchase decisions, and managing production.Livestock Production/Industries,

HEDGING WHOLESALE BEEF CUTS

Live cattle futures markets do not offer much opportunity for effective hedging of wholesale beef cuts. If a Choice-to-Select price spread futures contract were introduced this would enhance hedging effectiveness although likely not enough to encourage cross hedging. If a Choice boxed beef futures contract were introduced, hedging Choice wholesale beef cuts would be less risky and the addition of a Choice-to-Select price spread would enhance hedging effectiveness especially for Select wholesale beef cuts.Livestock Production/Industries, Marketing,

EFFECTS OF ADDITIONAL QUALITY ATTRIBUTES ON CONSUMER WILLINGNESS-TO-PAY FOR FOOD LABELS

Contingent valuation (CV), choice experiment (CE) and experimental auction (EA) or the combinations of the three methods are often used by researchers to elicit consumer willingness to pay for food attributes (food labels). One concern about using these approaches is that quality attributes of food provided to respondents are assumed independent of other attributes which are not provided to respondents during the survey. The limited attributes provided in a survey may lead respondents to allocate their budgets to those limited attributes rather than allocate their budgets to a larger number of product attributes to truly reveal their preferences. Surveys containing a series of online CEs were collected to investigate the effects of additional beef steak attributes on consumer WTP in two different US markets. Random parameters logit models are estimated for each CE in the questionnaires with survey results from both samples. The models with the different survey samples reveal consistent results regarding changes in WTP with more attributes added to the CEs. Consumer WTP for the most important attributes in the CE decreases when the number of attributes increases from three to four, while the WTP for the most important attributes increases when the number of attribute increase from four to five. The changes in the WTP for attributes depend on their relationships with the newly added attributes to the CEs and the number of attributes in CEs.Food Labels, Willingness-to-Pay, Choice Experiment, Demand and Price Analysis,

Crossover to Potential Energy Landscape Dominated Dynamics in a Model Glass-forming Liquid

An equilibrated model glass-forming liquid is studied by mapping successive configurations produced by molecular dynamics simulation onto a time series of inherent structures (local minima in the potential energy). Using this ``inherent dynamics'' approach we find direct numerical evidence for the long held view that below a crossover temperature, $T_x$, the liquid's dynamics can be separated into (i) vibrations around inherent structures and (ii) transitions between inherent structures (M. Goldstein, J. Chem. Phys. {\bf 51}, 3728 (1969)), i.e., the dynamics become ``dominated'' by the potential energy landscape. In agreement with previous proposals, we find that $T_x$ is within the vicinity of the mode-coupling critical temperature $T_c$. We further find that at the lowest temperature simulated (close to $T_x$), transitions between inherent structures involve cooperative, string like rearrangements of groups of particles moving distances substantially smaller than the average interparticle distance.Comment: Expanded from 4 to 7 page

Optimized pulse sequences for suppressing unwanted transitions in quantum systems

We investigate the nature of the pulse sequence so that unwanted transitions in quantum systems can be inhibited optimally. For this purpose we show that the sequence of pulses proposed by Uhrig [Phys. Rev. Lett. \textbf{98}, 100504 (2007)] in the context of inhibition of environmental dephasing effects is optimal. We derive exact results for inhibiting the transitions and confirm the results numerically. We posit a very significant improvement by usage of the Uhrig sequence over an equidistant sequence in decoupling a quantum system from unwanted transitions. The physics of inhibition is the destructive interference between transition amplitudes before and after each pulse.Comment: 5 figure

FACTORS AFFECTING LIVE CATTLE BASIS

Cattle producers and beef packers need to understand basis determinants as they develop price expectations and make pricing, hedging, and forward contracting decisions. This study empirically estimated factors explaining variability in monthly fed cattle basis. The five main results regarding live cattle basis are 1) corn price is an important determinant, 2) a change in the value of the Choice-to-Select spread positively affects basis, 3) changes in the levels of captive supplies have no significant statistical or economic impact on basis 4) the June 1995 live cattle futures contract did not impact basis, and 5) both market fundamentals and seasonal components are important basis determinants.basis, fed cattle, cattle prices, Livestock Production/Industries, Marketing,