Satellite Test Assistant Robot (STAR)

A three-year, three-phase program to demonstrate the applicability of telerobotic technology to the testing of satellites and other spacecraft has been initiated. Specifically, the objectives are to design, fabricate, and install into the JPL 25-ft. Space Simulator (SS) a system that will provide the capability to view test articles from all directions in both the visible and infrared (IR) spectral regions, to automatically map the solar flux intensity over the entire work volume of the chamber, and to provide the capability for leak detection. The first year's work, which provides a vertically mobile viewing platform equipped with stereo cameras, will be discussed. Design constraints and system implementation approaches mandated by the requirements of thermal vacuum operation will be emphasized

Animal Behaviour and Pasture Depletion in a Pasture-Based Automatic Milking System

In an automatic milking system (AMS) feed is used as an incentive to encourage voluntary and distributed cow traffic to the milking unit (Prescott et al. 1998). Therefore the timing, placement and size of feed allocations need to be managed in order to achieve targeted milking events per day. Behavioural studies allow the construction of time budgets (Gibb et al. 1998), and aid understanding of how cows modify their behaviour under different management regimes (Johansson et al. 1999). To date there are no published reports on how different location of feed incentives affect cows’ behaviour upon arrival at a pasture allocation in pasture-based AMS. A behavioural study was conducted in a pasture-based AMS where cows received supplementary feed either prior to (PRE), or immediately after (POST) milking. It was hypothesised that as PRE cows would have spent comparatively more time than POST cows since they ate their respective allocation of supplementary feed (at the time of exiting the dairy), they would be more motivated to go to the paddock in search of additional feed. Thus they would graze more intensively once they entered their pasture allocation

Problems encountered during impact calculations using analytic equations of state

During modeling of the impact of a projectile on a target or other calculations that bring materials together at high velocities, computer simulations of materials being shocked to high pressure and then releasing to low pressure are performed. Depending on the circumstances, the release to low pressure is often accompanied by release to a very low density. Numerical problems leading to very large sound speeds (and thus small time steps) or to negative Lagrangian volumes have been encountered during MESA-2D calculations of this nature. These problems can be traced to the behavior of the equation of state (EOS) in the limit as the density becomes much less than the normal or reference density. Although analytic solutions for expansion isentropes may show acceptable behavior in the low-density limit, numerical solutions can show undesirable behavior. Examples of this undesirable behavior in the low-density regime are given for some simple, analytic equations of state that have closed-form solutions for isentropes. The behavior of three analytic EOSs that are frequently used in MESA-2D calculations are then discussed. These EOSs are the Los Alamos EOS, the MESA polynomial EOS, and a Mie-Gruneisen EOS based on a linear relation between shock and particle velocity. The problems in the low-density region can be corrected for the Los Alamos EOS and the MESA polynomial EOS by the proper choice of EOS coefficients in the expansion region (density less than the reference density). Problems with the Mie-Gruneisen EOS can be corrected if the functional relationship between the Gruneisen parameter ({Tau}) and density differs above and below the reference density

Comparison of Two Systems of Pasture Allocation on Milking Intervals and Total Daily Milk Yield of Dairy Cows in a Pasture-Based Automatic Milking System

In pasture-based automatic milking systems (AMS), cows usually have a lower milking frequency (MF, the number of milking events in any 24 h period) than those reported in indoor housing systems (García and Fulkerson 2005). Moreover, milking intervals (MI, the interval between consecutive milking events, measured at every milking session in hours since the previous milking event) are higher, with up to 30% of milking events occurring with intervals above 16 h in grazing systems (NA Lyons unpublished data). Milking events occurring with long intervals have a negative effect on milk yield (Schmidt 1960) and udder health (Hammer et al. 2012). Recognising that feed is the main incentive to achieve voluntary cow traffic (Prescott et al. 1998), some initial reports have depicted the potential importance and effect of incentives put in place per day (Jago et al. 2007). Yet to date no research has been published that quantifies the actual impact of number of feed allocations, on animal performance in pasture-based systems. The aim of this study was to determine the impact of 2 different grazing treatments (2-way grazing [2WG] versus 3-way grazing [3WG] allocations of feed per 24 h period), on MI, MF and daily milk yield (DY, in kg milk/d). It was hypothesised that an increase in frequency of feed allocation would result in increased cow traffic, MF and DY

Groundwater chemistry along flow paths between a proposed repository site and the accessible environment

The Nevada Nuclear Waste Storage Investigations Program of the Department of Energy is investigating Yucca Mountain in the Nevada Test Site as a possible repository location. As part of this investigation, the groundwater from all pumped wells in and near the site has been sampled and analyzed; the results are reported in this document. The speciation and solubility of nuclear waste elements in these groundwaters have been calculated using the EQ3/6 computer code. Estimates have also been made of the pH and Eh buffering capacity of the water/rock system of Yucca Mountain

Attachment accuracy of a novel prototype robotic rotary and investigation of two management strategies for incomplete milked quarters

Throughout 2009 and 2010, FutureDairy (Camden, NSW, Australia) was involved in testing a novel prototype robotic rotary (RR). The commercial version RR is expected to be capable of carrying out 90 milkings per hour. To achieve the high throughput the rotary rotates the cow to the cup attachment robot and then around the platform in a stop–start fashion. The robot does not remain with the cow during the entire milking process. When not all teat cups are attached during a milking session there is an opportunity for cows to be sent back to the waiting yard for a second milking attempt. The study presented here was designed to test whether or not the extension of the interval to a second milking attempt improved milking success of incompletely milked cows. It was expected that with an increased milking interval between the two subsequent milkings the changes to the udder conformation could positively affect the attachment success at the second attempt. The 1 h milking interval treatment (1 h) simulated cows being drafted directly back to the pre-milking waiting yard, whilst the 3 h milking interval treatment (3 h) was designed to simulate cows being drafted back after accessing post-milking supplementary feed on a feedpad. The results presented in this manuscript showed no significant difference between the frequencies of successful attachment in the second attempt between the 1 h and 3 h treatments indicating that a reasonable level of flexibility exists with management of incompletely milked cows and dairy layout designs. Milk production level affected the probability of success at second attempt, which was about 7.5 times higher in cows with an average milk production level greater than 19.3 kg than those with less than 10.8 kg. When looking at the total proportion of cows successfully milked after two attempts, it was found that successful milking was more likely in multiparous cows compared to primiparous cows. Highlights • We studied management options for incompletely milked cows on a robotic rotary. • Firstly cows returned to waiting yard with approx. 1 h interval between attempts. • Secondly cows returned to waiting yard via feed pad – approx. 3 h between attempts. • No difference found between 1 and 3 h intervals on attachment success. • Level of flexibility exists with management of incompletely milked cows. Keywords: Success-rate; Pasture based; Automatic milking system; Robotic rotary; DairyDairy Australia, DeLaval, Department of Primary Industries NSW and The University of Sydney

System Fitness of Grazeable Forages for Large Herds in Automatic Milking Systems

Automatic milking rotary (AMR) systems have the capacity to milk 800 cows. To maintain a pasture-based system whereby \u3e 50% of the total diet is pasture (Garcia and Fulkerson, 2005), large herds milked by AMR will be required to walk significant distances. Walking distances of greater than 1-km are associated with an increased incidence of undesirably long milking intervals and reduced milk yield (Lyons N, unpubl. data). The aim of this study was to investigate the total land area required and associated walking distance for large automatic milking system (AMS) herds when incorporating complementary forage rotations (CFR; Garcia et al., 2008) into the system

Factors affecting reproductive performance of dairy cows in a pasture-based, automatic milking system research farm: a retrospective, single-cohort study

A retrospective single cohort study was conducted to identify production and health factors associated with reproductive performance in a pasture-based automatic milking system research farm. The calving system of this herd shifted from split calving to year round calving gradually during the study period. Data from 365 cows with 798 lactations were analysed in the study. Reproductive outcome variables of interest were intervals from calving to first oestrus, to first insemination, and to conception as well as number of inseminations per conception, probability of submission for insemination by 80 days in milk, probability of conception by 100 days in milk and probability of conception at first insemination. Production factors (milk yield and its composition; milking frequency), record of periparturient disease, parity and season of calving were considered as predictor variables. The associations between predictor and outcome variables were assessed by multivariable linear regression, logistic regression and survival analyses for quantitative, binary and time-to-event outcomes, respectively. Average milk yield and milking frequency during 100 days in milk were not significantly associated with any of the reproductive measures. The likelihood of conception by 100 days in milk decreased gradually with year of automatic milking systems commissioning. Cows calved in autumn were 43% (hazard ratio: 1.43, P < 0.05) more likely to conceive compared to cows that calved in summer. Multiparous cows were more likely (P < 0.05) to be recorded for oestrus compared to primiparous cows. Twinning was negatively associated with the reproductive outcomes measured in the automatic milking systems research herd. Milk yield and milking frequency during 100 days in milk had no effect on reproductive measures in the pasture-based automatic milking system research herd. Key words: Reproduction, Automatic Milking System, Pasture-Based Syste

High-precision molecular dynamics simulation of UO2-PuO2: superionic transition in uranium dioxide

Our series of articles is devoted to high-precision molecular dynamics simulation of mixed actinide-oxide (MOX) fuel in the rigid ions approximation using high-performance graphics processors (GPU). In this article we assess the 10 most relevant interatomic sets of pair potential (SPP) by reproduction of the Bredig superionic phase transition (anion sublattice premelting) in uranium dioxide. The measurements carried out in a wide temperature range from 300K up to melting point with 1K accuracy allowed reliable detection of this phase transition with each SPP. The {\lambda}-peaks obtained are smoother and wider than it was assumed previously. In addition, for the first time a pressure dependence of the {\lambda}-peak characteristics was measured, in a range from -5 GPa to 5 GPa its amplitudes had parabolic plot and temperatures had linear (that is similar to the Clausius-Clapeyron equation for melting temperature).Comment: 7 pages, 6 figures, 1 tabl

Factors affecting reproductive performance of dairy cows in a pasture-based, automatic milking system research farm: a retrospective, single-cohort study

A retrospective single cohort study was conducted to identify production and health factors associated with reproductive performance in a pasture-based automatic milking system research farm. The calving system of this herd shifted from split calving to year round calving gradually during the study period. Data from 365 cows with 798 lactations were analysed in the study. Reproductive outcome variables of interest were intervals from calving to first oestrus, to first insemination, and to conception as well as number of inseminations per conception, probability of submission for insemination by 80 days in milk, probability of conception by 100 days in milk and probability of conception at first insemination. Production factors (milk yield and its composition; milking frequency), record of periparturient disease, parity and season of calving were considered as predictor variables. The associations between predictor and outcome variables were assessed by multivariable linear regression, logistic regression and survival analyses for quantitative, binary and time-to-event outcomes, respectively. Average milk yield and milking frequency during 100 days in milk were not significantly associated with any of the reproductive measures. The likelihood of conception by 100 days in milk decreased gradually with year of automatic milking systems commissioning. Cows calved in autumn were 43% (hazard ratio: 1.43, P < 0.05) more likely to conceive compared to cows that calved in summer. Multiparous cows were more likely (P < 0.05) to be recorded for oestrus compared to primiparous cows. Twinning was negatively associated with the reproductive outcomes measured in the automatic milking systems research herd. Milk yield and milking frequency during 100 days in milk had no effect on reproductive measures in the pasture-based automatic milking system research herd. Key words: Reproduction, Automatic Milking System, Pasture-Based Syste