34 Search Results

In this study we describe RooFitUnfold, an extension of the RooFit statistical software package to treat unfolding problems, and which includes most of the unfolding methods that commonly used in particle physics. The package provides a common interface to these algorithms as well as common uniform methods to evaluate their performance in terms of bias, variance and coverage. In this paper we exploit this common interface of RooFitUnfold to compare the performance of unfolding with the Richardson–Lucy, Iterative Dynamically Stabilized, Tikhonov, Gaussian Process, bin-by-bin and inversion methods on several example problems.

There is considerable focus on technology manufacturing locations and the value in funding innovation when upstream products are not manufactured within a domestic economy. Light-emitting diodes (LEDs) are such an upstream product. Here, we evaluate the value added along the supply chain of luminaires, a product that utilizes LEDs, using bottom-up cost modelling. Coupling the results with analysis of shipping cost and time, this analysis examines how advances in LEDs can incentivize LED luminaire adoption leading to the potential for significant domestic manufacturing effects even if the upstream products are produced in other economies.

In this work, we present a measurement of the cosmic microwave background (CMB) lensing potential using 500 deg$^2$ of 150 GHz data from the SPTpol receiver on the South Pole Telescope. The lensing potential is reconstructed with signal-to-noise per mode greater than unity at lensing multipoles $$L \lesssim 250$$, using a quadratic estimator on a combination of CMB temperature and polarization maps. We report measurements of the lensing potential power spectrum in the multipole range of $100< L < 2000$ from sets of temperature-only, polarization-only, and minimum-variance estimators. We measure the lensing amplitude by taking the ratio of the measuredmore » spectrum to the expected spectrum from the best-fit $$\Lambda$$CDM model to the $$\textit{Planck}$$ 2015 TT+lowP+lensing dataset. For the minimum-variance estimator, we find $$A_{\rm{MV}} = 0.944 \pm 0.058{\rm (Stat.)}\pm0.025{\rm (Sys.)}$$; restricting to only polarization data, we find $$A_{\rm{POL}} = 0.906 \pm 0.090 {\rm (Stat.)} \pm 0.040 {\rm (Sys.)}$$. Considering statistical uncertainties alone, this is the most precise polarization-only lensing amplitude constraint to date (10.1 $$\sigma$$), and is more precise than our temperature-only constraint. We perform null tests and consistency checks and find no evidence for significant contamination.« less

Summary Photoacclimation consists of short‐ and long‐term strategies used by photosynthetic organisms to adapt to dynamic light environments. Observable photophysiology changes resulting from these strategies have been used in coarse‐grained models to predict light‐dependent growth and photosynthetic rates. However, the contribution of the broader metabolic network, relevant to species‐specific strategies and fitness, is not accounted for in these simple models. We incorporated photophysiology experimental data with genome‐scale modeling to characterize organism‐level, light‐dependent metabolic changes in the model diatom Phaeodactylum tricornutum . Oxygen evolution and photon absorption rates were combined with condition‐specific biomass compositions to predict metabolic pathway usage for cellsmore » acclimated to four different light intensities. Photorespiration, an ornithine‐glutamine shunt, and branched‐chain amino acid metabolism were hypothesized as the primary intercompartment reductant shuttles for mediating excess light energy dissipation. Additionally, simulations suggested that carbon shunted through photorespiration is recycled back to the chloroplast as pyruvate, a mechanism distinct from known strategies in photosynthetic organisms. Our results suggest a flexible metabolic network in P. tricornutum that tunes intercompartment metabolism to optimize energy transport between the organelles, consuming excess energy as needed. Characterization of these intercompartment reductant shuttles broadens our understanding of energy partitioning strategies in this clade of ecologically important primary producers.« less

An analysis was performed to determine the risk posed by wind turbine fragments on roads and buildings at the National Wind Technology Center at the National Renewable Energy Laboratory. The authors used a previously developed model of fragment trajectory and took into account the wind speed/direction distribution at the site and the probability of rotor failure. The site-specific risk was assessed by determining the likelihood of impact and related consequences. For both the roads and buildings, the risk varied from low to routine, which was considered acceptable.

Performing analysis or generating visualizations concurrently with high performance simulations can yield great benefits compared to post-processing data. Writing and reading large volumes of data can be reduced or eliminated, thereby producing an I/O cost savings. One such method for concurrent simulation and analysis is in transit - streaming data from the resource running the simulation to a separate resource running the analysis. In transit analysis can be beneficial since computational resources may not have certain resources needed for visualization and analysis (e.g. GPUs) and to reduce the impact of performing analysis tasks to the run time of the simulation.more » When sending and receiving data in transit, data redistribution mechanisms are needed in order to support heterogeneous data layouts that may be required by the simulation and analysis applications. The work described in this paper compares two mechanisms for on-the-fly data redistribution when streaming data in parallel between two distributed memory applications. Finally, our results show that it is often more advantageous to stream data in the same layout as the sender and redistribute data amongst processes on the receiving end than to stream data in the final layout needed by the receiver.« less

Abstract Foot and Mouth Disease ( FMD ) is endemic in Nepal and causes substantial economic losses in the livestock industry. The goal of this study was to perform an epidemiological analysis of FMD outbreaks reported to the Veterinary Epidemiology Center, Tripureshwor, Nepal during 2010–2015, in order to strengthen the National FMD Control Program. These current data were considered in the context of historical data on FMD virus ( FMDV ) serotypes detected in the country between 1965 and 2015. During 2010–2015, a total of 1333 livestock holdings reported FMD outbreaks in Nepal. On average, 71.2 animals were affected inmore » each outbreak, with a case fatality rate of 3.6%. FMD was reported throughout the country, and the proportion of affected holdings was not significantly among eco‐zones, regions, or species. The Hill eco‐zone had the highest number of holdings affected (782), followed by Mountain (304), and Terai (247). When analysed by the developmental region, the Western (381) and Central (368) Developmental Regions had the highest numbers of holdings affected. Cattle were the most frequently affected species (39%), followed by buffalo (33%), and goats (19%). FMD occurred throughout the year, with peaks in winter (December/January) and in the pre‐monsoon period (April/May). Between 1965 and 2015 FMDV serotype O had the highest prevalence (81%), followed by Asia‐1 (11%), A (6%), and C (2%). Serotype C was not detected after 1996, and only serotype O was reported after 2011. These descriptive analyses provide critical landmarks to establish baselines, and document early progress of the ongoing Progressive Control Pathway of FMD ( PCP ‐ FMD ) which could be useful in Nepal and other South Asian nations.« less

Several endeavors have been made over the years to estimate the sensitivity of audible scan surveys. Some estimates involved certain factors of the background count rate, while others involved calculations utilizing parameters pulled from the normal (Gaussian) distribution, regardless of background count rate. This paper discusses the results of a purely Poisson-based calculational method for the determination of appropriate decision levels and affiliated detection limits associated with health physics audible scan surveys. Comparisons are made to the other approaches and to empirical tests, where available. Although agreement with previous estimates can be had over limited ranges of background count rate,more » order-of-magnitude differences are possible outside of those ranges. The previous estimates are generally conservative at the higher count rates yet quite nonconservative at the lowest count rates. Several real-life operational examples are provided that illustrate the approach.« less

We demonstrate how the wavelet transform, which is a powerful tool for compression, filtering, and scaling analysis of signals, may be used to separate large- and short-scale electron density features in X-ray diffraction patterns. Wavelets can isolate the electron density associated with delocalized bonds from the much stronger background of highly localized core electrons. The wavelet-processed signals clearly reveal the bond formation and breaking in the early steps of the photoinduced pericyclic ring opening reaction of 1,3-cyclohexadiene, which are not resolved in the bare signal.

The analyses of thermochemically-derived bio-oil properties and composition are challenging due to the diversity of compounds present and the reactivity of the oils. There are currently a variety of techniques used and no standard method established for the analysis of the molecular weight distribution, weight average molecular weight (Mw) and other molecular weight metrics of bio-oils. This review focuses on the challenges and variation in methodologies employed for the analysis of bio-oils on the basis of molecular weight, particularly by gel permeation chromatography (GPC). GPC is the most practical means for determination of molecular weight metrics of bio-oils but needsmore » to be refined using appropriate standards and/or detectors to ensure consistency and accurate quantification of molecular weight metrics. Future method development for a robust technique with accurate and comparable molecular weight data should focus on GPC with multiple detection methodology on whole bio-oils, verified relative to another technique such as mass spectrometry (MS). MS techniques, such as Fourier transform-ion cyclotron resonance (FT-ICR MS), have also been utilized for the determination of molecular weight distribution of bio-oils and are briefly addressed in this review. Many MS methods can provide extensive characterization and structural speciation of components in bio-oils, and while accurate molecular weight metrics can be obtained with the appropriate use of ionization techniques and optimized parameters to ensure appropriate range of m/z and signals representative of abundance, MS is not a robust or an economically practical method for routine molecular weight analyses. Physical separation techniques such as preparative scale GPC, distillation, and liquid-liquid extraction methods are also briefly addressed in this review in the context of molecular weight analyses.« less