Comparison of Gaussian process modeling software

Gaussian process fitting, or kriging, is often used to create a model from a set of data. Many available software packages do this, but we show that very different results can be obtained from different packages even when using the same data and model. We describe the parameterization, features, and optimization used by eight different fitting packages that run on four different platforms. We then compare these eight packages using various data functions and data sets, revealing that there are stark differences between the packages. In addition to comparing the prediction accuracy, the predictive variance--which is important for evaluating precision of predictions and is often used in stopping criteria--is also evaluated

Structural Relationships for National and regional Beef Cattle Production

Changes have occurred in recent years which have produced changes in the beef industry. Structural relationships that existed for the producer-feeder are not necessarily important in the operation of the cow-calf operator or the feed-lot operator. Because of these changes, a more thorough knowledge of the supply response of a small regional breakdown of the beef cattle industry should be available to farmers, econmists, outlook workers and policy makers in the agricultural industry. The study examines cow-calf operations and feed-lot operations to investigate U.S. beef calf production and develop an economic model for number of beef calves produced by region in the U.S

On the Number of Facets of Three-Dimensional Dirichlet Stereohedra III: Full Cubic Groups

We are interested in the maximum possible number of facets that Dirichlet stereohedra for three-dimensional crystallographic groups can have. The problem for non-cubic groups was studied in previous papers by D. Bochis and the second author (Discrete Comput. Geom. 25:3 (2001), 419-444, and Beitr. Algebra Geom., 47:1 (2006), 89-120). This paper deals with ''full'' cubic groups, while ''quarter'' cubic groups are left for a subsequent paper. Here, ''full'' and ''quarter'' refers to the recent classification of three-dimensional crystallographic groups by Conway, Delgado-Friedrichs, Huson and Thurston (math.MG/9911185, Beitr. Algebra Geom. 42.2 (2001), 475-507). Our main result in this paper is that Dirichlet stereohedra for any of the 27 full groups cannot have more than 25 facets. We also find stereohedra with 17 facets for one of these groups.Comment: 28 pages, 12 figures. Changes from v1: apart of some editing (mostly at the end of the introduction) and addition of references, an appendix has been added, which analyzes the case where the base point does not have trivial stabilize

Effects of Modified Distillers Grains and Corn Ratios as Supplements in Diets Varying in Forage Quality on Performance of Growing Beef Steers

Distillers grains (DG) have been intensively used for beef production, but prices relative to corn vary such that it may be beneficial to displace a portion of DG with corn in certain circumstances. Four ratios of supplemental energy (40% of diet DM) from modified distillers grains and corn (100:0, 80:20, 60:40, and 40:60) were supplemented in one of 3 forage diets (56% of diet DM) and evaluated for performance. Forages were high (brome hay + sorghum silage) or low quality. Low quality forages were corn residue baled through conventional rake and bale, or by disengaging the spreader on the combine and baling the tailings (easy bale). Steers fed the high quality forage had greater ADG due to greater DMI, but similar F:G as both residue forage diets, which were not different. Decreasing the ratio of modified DG:corn linearly decreased ADG and resulted in poorer F:G

Spontaneous Symmetry Breaking in Two-Channel Asymmetric Exclusion Processes with Narrow Entrances

Multi-particle non-equilibrium dynamics in two-channel asymmetric exclusion processes with narrow entrances is investigated theoretically. Particles move on two parallel lattices in opposite directions without changing them, while the channels are coupled only at the boundaries. A particle cannot enter the corresponding lane if the exit site of the other lane is occupied. Stationary phase diagrams, particle currents and densities are calculated in a mean-field approximation. It is shown that there are four stationary phases in the system, with two of them exhibiting spontaneous symmetry breaking phenomena. Extensive Monte Carlo computer simulations confirm qualitatively our predictions, although the phase boundaries and stationary properties deviate from the mean-field results. Computer simulations indicate that several dynamic and phase properties of the system have a strong size dependency, and one of the stationary phases predicted by the mean-field theory disappears in the thermodynamic limit.Comment: 13 page

Associations of the lipidome with ageing, cognitive decline and exercise behaviours

One of the most recognisable features of ageing is a decline in brain health and cognitive dysfunction, which is associated with perturbations to regular lipid homeostasis. Although ageing is the largest risk factor for several neurodegenerative diseases such as dementia, a loss in cognitive function is commonly observed in adults over the age of 65. Despite the prevalence of normal age-related cognitive decline, there is a lack of effective methods to improve the health of the ageing brain. In light of this, exercise has shown promise for positively influencing neurocognitive health and associated lipid profiles. This review summarises age-related changes in several lipid classes that are found in the brain, including fatty acyls, glycerolipids, phospholipids, sphingolipids and sterols, and explores the consequences of age-associated pathological cognitive decline on these lipid classes. Evidence of the positive effects of exercise on the affected lipid profiles are also discussed to highlight the potential for exercise to be used therapeutically to mitigate age-related changes to lipid metabolism and prevent cognitive decline in later life

Aircraft and avionic related research required to develop an effective high-speed runway exit system

Research was conducted to increase airport capacity by studying the feasibility of the longitudinal separation between aircraft sequences on final approach. The multidisciplinary factors which include the utility of high speed exits for efficient runway operations were described along with recommendations and highlights of these studies

Charge Exchange Spectra of Hydrogenic and He-like Iron

We present H-like Fe XXVI and He-like Fe XXV charge-exchange spectra resulting from collisions of highly charged iron with N2 gas at an energy of 10 eV/amu in an electron beam ion trap. Although individual high-n emission lines are not resolved in our measurements, we observe that the most likely level for Fe25+ --> Fe24+ electron capture is n~9, in line with expectations, while the most likely value for Fe26+ --> Fe25+ charge exchange is significantly higher. In the Fe XXV spectrum, the K-alpha emission feature dominates, whether produced via charge exchange or collisional excitation. The K-alpha centroid is lower in energy for the former case than the latter (6666 versus 6685 eV, respectively), as expected because of the strong enhancement of emission from the forbidden and intercombination lines, relative to the resonance line, in charge-exchange spectra. In contrast, the Fe XXVI high-n Lyman lines have a summed intensity greater than that of Ly-alpha, and are substantially stronger than predicted from theoretical calculations of charge exchange with atomic H. We conclude that the angular momentum distribution resulting from electron capture using a multi-electron target gas is significantly different from that obtained with H, resulting in the observed high-n enhancement. A discussion is presented of the relevance of our results to studies of diffuse Fe emission in the Galactic Center and Galactic Ridge, particularly with ASTRO-E2/Suzaku.Comment: 16 pages, 4 figures (3 color), accepted by Ap

Impacts of alternative grassland management regimes on the population ecology of grassland birds

We investigated the impacts of rangeland management practices on the diversity, density, and nest survival of grassland songbirds and on the demography, habitat selection, and population viability of Greater Prairie-Chickens (Tympanuchus cupido). Our study site was located in eastcentral Kansas and included portions of Chase, Greenwood, Lyon, and Morris Counties. We had access to ~1,100 km2 of private and public lands. Over 95% of the land was privately owned (~1040 km2), and the remaining ~5% was the Tallgrass Prairie National Preserve. Our final project report is based on data collected during a 3-year period from Feb. 2011 through Feb. 2014. Our study focused on grassland songbirds and Greater Prairie-Chickens as indicators of ecosystem response. Our analyses are based on direct comparisons between monitoring efforts in pastures managed with patch-burn grazing (PBG) and pastures managed with traditional intensive early stocking and annual burning (IESB).Citation: Sandercock, B.K., V.L. Winder, A.E. Erickson, and L.B. McNew. 2014. Impacts of alternative grassland management regimes on the population ecology of grassland birds. Kansas Department of Wildlife, Parks and Tourism, Final Project Report for Award No. KDWP-W-67-R. (technical report)

Impact of Cleaning Frequency on Nitrogen Balance in Open Feedlot Pens

Pen cleaning frequency of feedlot pens was evaluated during the summer of 2001 and 2002. Dry matter, organic matter and nitrogen recoveries were evaluated on a per head basis. Cleaning pens monthly compared to cleaning at the end of the feeding period resulted in significantly more DM, OM and N recovered. Cleaning pens every month increased N removal by 7.0 lb per steer (49.9% increase) above manure N removed at the end of the feeding period