The human as a detector of changes in variance and bandwidth

The detection of changes in random process variance and bandwidth was studied. Psychophysical thresholds for these two parameters were determined using an adaptive staircase technique for second order random processes at two nominal periods (1 and 3 seconds) and damping ratios (0.2 and 0.707). Thresholds for bandwidth changes were approximately 9% of nominal except for the (3sec,0.2) process which yielded thresholds of 12%. Variance thresholds averaged 17% of nominal except for the (3sec,0.2) process in which they were 32%. Detection times for suprathreshold changes in the parameters may be roughly described by the changes in RMS velocity of the process. A more complex model is presented which consists of a Kalman filter designed for the nominal process using velocity as the input, and a modified Wald sequential test for changes in the variance of the residual. The model predictions agree moderately well with the experimental data. Models using heuristics, e.g. level crossing counters, were also examined and are found to be descriptive but do not afford the unification of the Kalman filter/sequential test model used for changes in mean

Develop New Hog Watering System

Agricultural engineers at Iowa State Colle have developed a continuously circulating hog watering system. It eliminates the need for individual heating units in the waterers to prevent winter freeze-ups

Experimental characterization of the effects of pneumatic tubing on unsteady pressure measurements

Advances in aircraft control system designs have, with increasing frequency, required that air data be used as flight control feedback. This condition requires that these data be measured with accuracy and high fidelity. Most air data information is provided by pneumatic pressure measuring sensors. Typically unsteady pressure data provided by pneumatic sensing systems are distorted at high frequencies. The distortion is a result of the pressure being transmitted to the pressure sensor through a length of connective tubing. The pressure is distorted by frictional damping and wave reflection. As a result, air data provided all-flush, pneumatically sensed air data systems may not meet the frequency response requirements necessary for flight control augmentation. Both lab and flight test were performed at NASA-Ames to investigate the effects of this high frequency distortion in remotely located pressure measurement systems. Good qualitative agreement between lab and flight data are demonstrated. Results from these tests are used to describe the effects of pneumatic distortion in terms of a simple parametric model

Considerations for the design of an onboard air traffic situation display

The basic concept of remoting information to the cockpit is used to design and develop a computerized airborne traffic situation display device that automatically selects and presents segments of a controller's scope to the aircraft pilot via a narrow band digital data link. These data are integrated with aircraft heading and navigation information to provide a display useful in congested air space. The display can include alphanumerical symbols, air route maps, and controller instructions

Management Production Systems and Timing Strategies for Cull Cows

Replaced with revised version of paper 06/04/09.Cattle, cull cows, management, marketing, production systems, timing, Farm Management, Marketing,

Influence of Beginning Body Condition Scores on Net Returns From Feeding Cull Cows

The impact of beginning body condition scores on returns from feeding cull cows was investigated in a two year experiment. In each of two culling years, physical performance data and financial data were measured at approximately monthly intervals for culls on pasture versus dry lot. Specifically, data was collected for cows culled in October 2007 and held through April 2008 and for cows culled in October 2008 and held through March 2009. We examine the sensitivity of net returns relative to the choice of body condition score as a sorting trigger for heavy versus thin cows. In this two year study, while a pasture system was generally more profitable than a drylot system, thin cows were typically more profitable than cows with higher BCS, regardless of the feeding system. The importance of the sorting criteria is highlighted in year two. Using the lower BCS criteria for sorting is the only scenario that generates positive net returns, albeit small. Thus, decisions regarding cull cow retention and feeding should consider body condition scores.Agricultural and Food Policy,

The feeding-stuffs inspection for 1913, Bulletin, no. 165

The Bulletin is a publication of the New Hampshire Agricultural Experiment Station, College of Life Sciences and Agriculture, University of New Hampshire, Durham, New Hampshire

Analysis of fertilizers for 1916, Bulletin, no. 179

The Bulletin is a publication of the New Hampshire Agricultural Experiment Station, College of Life Sciences and Agriculture, University of New Hampshire, Durham, New Hampshire

Analysis of feeding stuffs, Bulletin, no. 187

The Bulletin is a publication of the New Hampshire Agricultural Experiment Station, College of Life Sciences and Agriculture, University of New Hampshire, Durham, New Hampshire

Results of the feed inspection for 1910, Bulletin, no. 149

The Bulletin is a publication of the New Hampshire Agricultural Experiment Station, College of Life Sciences and Agriculture, University of New Hampshire, Durham, New Hampshire