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Sample records for chlorobium tepidum comparison

  1. Two genes encoding new carotenoid-modifying enzymes in the green sulfur bacterium Chlorobium tepidum.

    PubMed

    Maresca, Julia A; Bryant, Donald A

    2006-09-01

    The green sulfur bacterium Chlorobium tepidum produces chlorobactene as its primary carotenoid. Small amounts of chlorobactene are hydroxylated by the enzyme CrtC and then glucosylated and acylated to produce chlorobactene glucoside laurate. The genes encoding the enzymes responsible for these modifications of chlorobactene, CT1987, and CT0967, have been identified by comparative genomics, and these genes were insertionally inactivated in C. tepidum to verify their predicted function. The gene encoding chlorobactene glucosyltransferase (CT1987) has been named cruC, and the gene encoding chlorobactene lauroyltransferase (CT0967) has been named cruD. Homologs of these genes are found in the genomes of all sequenced green sulfur bacteria and filamentous anoxygenic phototrophs as well as in the genomes of several nonphotosynthetic bacteria that produce similarly modified carotenoids. The other bacteria in which these genes are found are not closely related to green sulfur bacteria or to one another. This suggests that the ability to synthesize modified carotenoids has been a frequently transferred trait.

  2. Genetic manipulation of carotenoid biosynthesis in the green sulfur bacterium Chlorobium tepidum.

    PubMed

    Frigaard, Niels-Ulrik; Maresca, Julia A; Yunker, Colleen E; Jones, A Daniel; Bryant, Donald A

    2004-08-01

    The green sulfur bacterium Chlorobium tepidum is a strict anaerobe and an obligate photoautotroph. On the basis of sequence similarity with known enzymes or sequence motifs, nine open reading frames encoding putative enzymes of carotenoid biosynthesis were identified in the genome sequence of C. tepidum, and all nine genes were inactivated. Analysis of the carotenoid composition in the resulting mutants allowed the genes encoding the following six enzymes to be identified: phytoene synthase (crtB/CT1386), phytoene desaturase (crtP/CT0807), zeta-carotene desaturase (crtQ/CT1414), gamma-carotene desaturase (crtU/CT0323), carotenoid 1',2'-hydratase (crtC/CT0301), and carotenoid cis-trans isomerase (crtH/CT0649). Three mutants (CT0180, CT1357, and CT1416 mutants) did not exhibit a discernible phenotype. The carotenoid biosynthetic pathway in C. tepidum is similar to that in cyanobacteria and plants by converting phytoene into lycopene using two plant-like desaturases (CrtP and CrtQ) and a plant-like cis-trans isomerase (CrtH) and thus differs from the pathway known in all other bacteria. In contrast to the situation in cyanobacteria and plants, the construction of a crtB mutant completely lacking carotenoids demonstrates that carotenoids are not essential for photosynthetic growth of green sulfur bacteria. However, the bacteriochlorophyll a contents of mutants lacking colored carotenoids (crtB, crtP, and crtQ mutants) were decreased from that of the wild type, and these mutants exhibited a significant growth rate defect under all light intensities tested. Therefore, colored carotenoids may have both structural and photoprotection roles in green sulfur bacteria. The ability to manipulate the carotenoid composition so dramatically in C. tepidum offers excellent possibilities for studying the roles of carotenoids in the light-harvesting chlorosome antenna and iron-sulfur-type (photosystem I-like) reaction center. The phylogeny of carotenogenic enzymes in green sulfur

  3. Exciton dynamics in the chlorosomal antennae of the green bacteria Chloroflexus aurantiacus and Chlorobium tepidum.

    PubMed Central

    Prokhorenko, V I; Steensgaard, D B; Holzwarth, A R

    2000-01-01

    The energy transfer processes in isolated chlorosomes from green bacteria Chlorobium tepidum and Chloroflexus aurantiacus have been studied at low temperatures (1.27 K) by two-pulse photon echo and one-color transient absorption techniques with approximately 100 fs resolution. The decay of the coherence in both types of chlorosomes is characterized by four different dephasing times stretching from approximately 100 fs up to 300 ps. The fastest component reflects dephasing that is due to interaction of bacteriochlorophylls with the phonon bath, whereas the other components correspond to dephasing due to different energy transfer processes such as distribution of excitation along the rod-like aggregates, energy exchange between different rods in the chlorosome, and energy transfer to the base plate. As a basis for the interpretation of the excitation dephasing and energy transfer pathways, a superlattice-like structural model is proposed based on recent experimental data and computer modeling of the Bchl c aggregates (1994. Photosynth. Res. 41:225-233.) This model predicts a fine structure of the Q(y) absorption band that is fully supported by the present photon echo data. PMID:11023914

  4. The three-dimensional structure of CsmA: a small antenna protein from the green sulfur bacterium Chlorobium tepidum.

    PubMed

    Pedersen, Marie Østergaard; Underhaug, Jarl; Dittmer, Jens; Miller, Mette; Nielsen, Niels Chr

    2008-08-20

    The structure of the chlorosome baseplate protein CsmA from Chlorobium tepidum in a 1:1 chloroform:methanol solution was determined using liquid-state NMR spectroscopy. The data reveal that the 59-residue protein is predominantly alpha-helical with a long helical domain extending from residues V6 to L36, containing a putative bacteriochlorophyll a binding domain, and a short helix in the C-terminal part extending from residues M41 to G49. These elements are compatible with a model of CsmA having the long N-terminal alpha-helical stretch immersed into the lipid monolayer confining the chlorosome and the short C-terminal helix protruding outwards, thus available for interaction with the Fenna-Matthews-Olson antenna protein.

  5. Two exopolyphosphatases with distinct molecular architectures and substrate specificities from the thermophilic green-sulfur bacterium Chlorobium tepidum TLS.

    PubMed

    Albi, Tomás; Serrano, Aurelio

    2014-09-01

    The genome of the thermophilic green-sulfur bacterium Chlorobium tepidum TLS possesses two genes encoding putative exopolyphosphatases (PPX; EC 3.6.1.11), namely CT0099 (ppx1, 993 bp) and CT1713 (ppx2, 1557 bp). The predicted polypeptides of 330 and 518 aa residues are Ppx-GppA phosphatases of different domain architectures - the largest one has an extra C-terminal HD domain - which may represent ancient paralogues. Both ppx genes were cloned and overexpressed in Escherichia coli BL21(DE3). While CtPPX1 was validated as a monomeric enzyme, CtPPX2 was found to be a homodimer. Both PPX homologues were functional, K(+)-stimulated phosphohydrolases, with an absolute requirement for divalent metal cations and a marked preference for Mg(2+). Nevertheless, they exhibited remarkably different catalytic specificities with regard to substrate classes and chain lengths. Even though both enzymes were able to hydrolyse the medium-size polyphosphate (polyP) P13-18 (polyP mix with mean chain length of 13-18 phosphate residues), CtPPX1 clearly reached its highest catalytic efficiency with tripolyphosphate and showed substantial nucleoside triphosphatase (NTPase) activity, while CtPPX2 preferred long-chain polyPs (>300 Pi residues) and did not show any detectable NTPase activity. These catalytic features, taken together with the distinct domain architectures and molecular phylogenies, indicate that the two PPX homologues of Chl. tepidum belong to different Ppx-GppA phosphatase subfamilies that should play specific biochemical roles in nucleotide and polyP metabolisms. In addition, these results provide an example of the remarkable functional plasticity of the Ppx-GppA phosphatases, a family of proteins with relatively simple structures that are widely distributed in the microbial world.

  6. Two exopolyphosphatases with distinct molecular architectures and substrate specificities from the thermophilic green-sulfur bacterium Chlorobium tepidum TLS.

    PubMed

    Albi, Tomás; Serrano, Aurelio

    2014-09-01

    The genome of the thermophilic green-sulfur bacterium Chlorobium tepidum TLS possesses two genes encoding putative exopolyphosphatases (PPX; EC 3.6.1.11), namely CT0099 (ppx1, 993 bp) and CT1713 (ppx2, 1557 bp). The predicted polypeptides of 330 and 518 aa residues are Ppx-GppA phosphatases of different domain architectures - the largest one has an extra C-terminal HD domain - which may represent ancient paralogues. Both ppx genes were cloned and overexpressed in Escherichia coli BL21(DE3). While CtPPX1 was validated as a monomeric enzyme, CtPPX2 was found to be a homodimer. Both PPX homologues were functional, K(+)-stimulated phosphohydrolases, with an absolute requirement for divalent metal cations and a marked preference for Mg(2+). Nevertheless, they exhibited remarkably different catalytic specificities with regard to substrate classes and chain lengths. Even though both enzymes were able to hydrolyse the medium-size polyphosphate (polyP) P13-18 (polyP mix with mean chain length of 13-18 phosphate residues), CtPPX1 clearly reached its highest catalytic efficiency with tripolyphosphate and showed substantial nucleoside triphosphatase (NTPase) activity, while CtPPX2 preferred long-chain polyPs (>300 Pi residues) and did not show any detectable NTPase activity. These catalytic features, taken together with the distinct domain architectures and molecular phylogenies, indicate that the two PPX homologues of Chl. tepidum belong to different Ppx-GppA phosphatase subfamilies that should play specific biochemical roles in nucleotide and polyP metabolisms. In addition, these results provide an example of the remarkable functional plasticity of the Ppx-GppA phosphatases, a family of proteins with relatively simple structures that are widely distributed in the microbial world. PMID:24969471

  7. Pump-probe anisotropies of Fenna-Matthews-Olson protein trimers from Chlorobium tepidum: a diagnostic for exciton localization?

    PubMed Central

    Savikhin, S; Buck, D R; Struve, W S

    1997-01-01

    Exciton calculations on symmetric and asymmetric Fenna-Matthews-Olson (FMO) trimers, combined with absorption difference anisotropy measurements on FMO trimers from the green bacterium Chlorobium tepidum, suggest that real samples exhibit sufficient diagonal energy disorder so that their laser-excited exciton states are noticeably localized. Our observed anisotropies are clearly inconsistent with 21-pigment exciton simulations based on a threefold-symmetric FMO protein. They are more consistent with a 7-pigment model that assumes that the laser-prepared states are localized within a subunit of the trimer. Differential diagonal energy shifts of 50 cm(-1) between symmetry-related pigments in different subunits are large enough to cause sharp localization in the stationary states; these shifts are commensurate with the approximately 95 cm(-1) inhomogeneous linewidth of the lowest exciton levels. Experimental anisotropies (and by implication steady-state linear and circular dichroism) likely arise from statistical averaging over states with widely contrasting values of these observables, in consequence of their sensitivity to diagonal energy disorder. PMID:9336204

  8. Electron transfer kinetics in purified reaction centers from the green sulfur bacterium Chlorobium tepidum studied by multiple-flash excitation.

    PubMed

    Kusumoto, N; Sétif, P; Brettel, K; Seo, D; Sakurai, H

    1999-09-14

    Reaction center preparations from the green sulfur bacterium Chlorobium tepidum, which contain monoheme cytochrome c, were studied by flash-absorption spectroscopy in the near-UV, visible, and near-infrared regions. The decay kinetics of the photooxidized primary donor P840(+), together with the amount of photooxidized cytochrome c, were analyzed along a series of four flashes spaced by 1 ms: 95% of the P840(+) was reduced by cytochrome c with a t(1/2) of approximately 65 micros after the first flash, 80% with a t(1/2) of approximately 100 micros after the second flash, and 23% with a t(1/2) of approximately 100 micros after the third flash; after the fourth flash, almost no cytochrome c oxidation occurred. The observed rates, the establishment of redox equilibrium after each flash, and the total amount of photooxidizable cytochrome c are consistent with the presence of two equivalent cytochrome c molecules per photooxidizable P840. The data are well fitted assuming a standard free energy change DeltaG degrees of -53 meV for electron transfer from one cytochrome c to P840(+), DeltaG degrees being independent of the oxidation state of the other cytochrome c. These observations support a model with two monoheme cytochromes c which are symmetrically arranged around the reaction center core. From the ratio of menaquinone-7 to the bacteriochlorophyll pigment absorbing at 663 nm, it was estimated that our preparations contain 0.6-1.2 menaquinone-7 molecules per reaction center. However, no transient signal due to menaquinone could be observed between 360 and 450 nm in the time window from 10 ns to 4 micros. No recombination reaction between the primary partners P840(+) and A(0)(-) could be detected under normal conditions. Such a recombination was observed (t(1/2) approximately 19 ns) under highly reducing conditions or after accumulation of three electrons on the acceptor side during a series of flashes, showing that the secondary acceptors can stabilize three electrons

  9. The crystal structure of ferritin from Chlorobium tepidum reveals a new conformation of the 4-fold channel for this protein family.

    PubMed

    Arenas-Salinas, Mauricio; Townsend, Philip D; Brito, Christian; Marquez, Valeria; Marabolli, Vanessa; Gonzalez-Nilo, Fernando; Matias, Cata; Watt, Richard K; López-Castro, Juan D; Domínguez-Vera, José; Pohl, Ehmke; Yévenes, Alejandro

    2014-11-01

    Ferritins are ubiquitous iron-storage proteins found in all kingdoms of life. They share a common architecture made of 24 subunits of five α-helices. The recombinant Chlorobium tepidum ferritin (rCtFtn) is a structurally interesting protein since sequence alignments with other ferritins show that this protein has a significantly extended C-terminus, which possesses 12 histidine residues as well as several aspartate and glutamic acid residues that are potential metal ion binding residues. We show that the macromolecular assembly of rCtFtn exhibits a cage-like hollow shell consisting of 24 monomers that are related by 4-3-2 symmetry; similar to the assembly of other ferritins. In all ferritins of known structure the short fifth α-helix adopts an acute angle with respect to the four-helix bundle. However, the crystal structure of the rCtFtn presented here shows that this helix adopts a new conformation defining a new assembly of the 4-fold channel of rCtFtn. This conformation allows the arrangement of the C-terminal region into the inner cavity of the protein shell. Furthermore, two Fe(III) ions were found in each ferroxidase center of rCtFtn, with an average FeA-FeB distance of 3 Å; corresponding to a diferric μ-oxo/hydroxo species. This is the first ferritin crystal structure with an isolated di-iron center in an iron-storage ferritin. The crystal structure of rCtFtn and the biochemical results presented here, suggests that rCtFtn presents similar biochemical properties reported for other members of this protein family albeit with distinct structural plasticity. PMID:25079050

  10. Electromagnetic study of the chlorosome antenna complex of Chlorobium tepidum.

    PubMed

    Valleau, Stéphanie; Saikin, Semion K; Ansari-Oghol-Beig, Davood; Rostami, Masoud; Mossallaei, Hossein; Aspuru-Guzik, Alán

    2014-04-22

    Green sulfur bacteria are an iconic example of nature's adaptation: thriving in environments of extremely low photon density, the bacterium ranks itself among the most efficient natural light-harvesting organisms. The photosynthetic antenna complex of this bacterium is a self-assembled nanostructure, ≈60 × 150 nm, made of bacteriochlorophyll molecules. We study the system from a computational nanoscience perspective by using electrodynamic modeling with the goal of understanding its role as a nanoantenna. Three different nanostructures, built from two molecular packing moieties, are considered: a structure built of concentric cylinders of aggregated bacteriochlorophyll d monomers, a single cylinder of bacteriochlorophyll c monomers, and a model for the entire chlorosome. The theoretical model captures both coherent and incoherent components of exciton transfer. The model is employed to extract optical spectra, concentration and depolarization of electromagnetic fields within the chlorosome, and fluxes of energy transfer for the structures. The second model nanostructure shows the largest field enhancement. Further, field enhancement is found to be more sensitive to dynamic noise rather than structural disorder. Field depolarization, however, is similar for all structures. This indicates that the directionality of transfer is robust to structural variations, while on the other hand, the intensity of transfer can be tuned by structural variations.

  11. Sorption of metals by Chlorobium spp.

    PubMed

    Garcia-Gil, J; Borrego, C

    1997-12-01

    The capacity of two species of green phototrophic sulfur bacteria, Chlorobium limicola and C. phaeobacteroides, to sorb several metal ions (Mn2+, Fe2+, Ni2+, Cu2+, Zn2+, Cd2+ and Pb2+) has been tested in laboratory batch cultures at increasing concentrations up to 2,000 mumol/l. Except for nickel--which was not sorbed to bacterial cells--the rest of metals tested were bound in a fast and passive process, which was mathematically described by means of Freundlich isotherms models. The sorption capacity of the two species studied were found to be dependent on the metal involved, whereas no differences were observed in the sorption intensity, suggesting that in all cases the sorption process proceeds in a similar way. Further, the comparison of the sorption intensity values as well as the metal recovery index (Ri), for both species, revealed that C. phaeobacteroides was more efficient that C. limicola to attach metal ions. The ecological significance of this ability in the water column of some stratified lakes, where coinciding maxima of ferrous iron and green photosynthetic sulfur bacteria are frequently found, is discussed.

  12. High-pressure hole-burning studies of the bacteriochlorophyll a antenna complex from Chlorobium tepidum

    SciTech Connect

    Reddy, N.R.S.; Jankowiak, R.; Small, G.J. |

    1995-10-26

    The dependence of the low-temperature Q{sub y} absorption and nonphotochemical hole-burned spectra of the title complex (also known as the FMO complex) on pressure (<= 700 MPa) is reported. Pressure-induced structural changes of the complex were found to be elastic. The linear pressure shifts at 4.2 K for the principal absorption bands at 805, 814 and 825 nm are -0.08, -0.11, and -0.11 cm{sup -1}/MPa, respectively. Importantly, the 825 and 814 nm absorption profiles (shape, intensity) are independent of pressure. The results establish that, even at the highest values used, pressure has only a weak effect on the pairwise excitonic couplings of the bacteriochlorophyll (BChl) molecules, inhomogeneous broadening, and electron-phonon coupling. The pressure dependence of the Q{sub y} spectrum and zero-phonon holes (ZPH) burned in the 825 nm band can be rationalized in terms of dispersion interactions when BChl occupation numbers for the exciton levels are taken into account. These ZPH, which are assigned to the lowest level at 827 nm, carry a width of 0.6 cm{sup -1} at 4.2 K, which is independent of the pressure at which the hole is burned. This width is ascribed to dephasing, T{sub 2} = 35 ps. Possible mechanisms for the dephasing are considered, and its pressure independence is discussed. 80 refs., 12 figs., 1 tab.

  13. Conformational heterogeneity of the Roc domains in C. tepidum Roc–COR and implications for human LRRK2 Parkinson mutations

    PubMed Central

    Rudi, Katharina; Ho, Franz Y.; Gilsbach, Bernd K.; Pots, Henderikus; Wittinghofer, Alfred; Kortholt, Arjan; Klare, Johann P.

    2015-01-01

    Ras of complex proteins (Roc) is a Ras-like GTP-binding domain that always occurs in tandem with the C-terminal of Roc (COR) domain and is found in bacteria, plants and animals. Recently, it has been shown that Roco proteins belong to the family of G-proteins activated by nucleotide (nt)-dependent dimerization (GADs). We investigated the RocCOR tandem from the bacteria Chlorobium tepidum with site-directed spin labelling and pulse EPR distance measurements to follow conformational changes during the Roco G-protein cycle. Our results confirm that the COR domains are a stable dimerization device serving as a scaffold for the Roc domains that, in contrast, are structurally heterogeneous and dynamic entities. Contrary to other GAD proteins, we observed only minor structural alterations upon binding and hydrolysis of GTP, indicating significant mechanistic variations within this protein class. Mutations in the most prominent member of the Roco family of proteins, leucine-rich repeat (LRR) kinase 2 (LRRK2), are the most frequent cause of late-onset Parkinson's disease (PD). Using a stable recombinant LRRK2 Roc-COR-kinase fragment we obtained detailed kinetic data for the G-protein cycle. Our data confirmed that dimerization is essential for efficient GTP hydrolysis and PD mutations in the Roc domain result in decreased GTPase activity. Previous data have shown that these LRRK2 PD-mutations are located in the interface between Roc and COR. Importantly, analogous mutations in the conserved C. tepidum Roc/COR interface significantly influence the structure and nt-induced conformational changes of the Roc domains. PMID:26310572

  14. Biological conversion of synthesis gas. [Chlorobium thiosulfatophilum, chlorobium phaeobacteroides, and Rhodospirillum rubrum

    SciTech Connect

    Not Available

    1992-01-06

    The anaerobic bacterium Rhodospirillum rubrum has been chosen for catalysis of the biological water gas shift reaction. Two bacteria, Chlorobium thiosulfatophilum and Chlorobium phaeobacteroides, are being evaluated as candidates for H{sub 2}S conversion to elemental sulfur. Since these latter two organisms both grow and convert H{sub 2}S in batch culture using standard basal medium, the choice of a suitable bacterium must be made in consideration of specific growth and uptake rates. Produced elemental sulfur stability against further oxidation to sulfate, and minimal use of H{sub 2} as a producing agent must also be considered. The effects of temperature on the performance of R. rubrum were evaluated. It was found that the cell concentration was highest at temperatures of 25 and 30{degree}C, and that the specific uptake rate was highest at temperatures of 30, 32 and 34{degree}C. No growth was observed at 37{degree}C. Also, temperature did not affect the yield of H{sub 2} from CO. Thus, R. rubrum may be used for biological rates gas shift at any temperature between 30 and 34{degree}C, although growth is maximized at lower temperatures. Preliminary studies with C. thiosulfatophilum showed rapid utilization of H{sub 2}S from the gas and liquid phases with subsequent production of elemental sulfur. Elemental sulfur production interfered with cell concentrations measurements, although a technique has been developed to rectify this problem.

  15. Membrane orientation of the FMO antenna protein from Chlorobaculum tepidum as determined by mass spectrometry-based footprinting.

    PubMed

    Wen, Jianzhong; Zhang, Hao; Gross, Michael L; Blankenship, Robert E

    2009-04-14

    The high excitation energy-transfer efficiency demanded in photosynthetic organisms relies on the optimal pigment-protein binding orientation in the individual protein complexes and also on the overall architecture of the photosystem. In green sulfur bacteria, the membrane-attached Fenna-Matthews-Olson (FMO) antenna protein functions as a "wire" to connect the large peripheral chlorosome antenna complex with the reaction center (RC), which is embedded in the cytoplasmic membrane (CM). Energy collected by the chlorosome is funneled through the FMO to the RC. Although there has been considerable effort to understand the relationships between structure and function of the individual isolated complexes, the specific architecture for in vivo interactions of the FMO protein, the CM, and the chlorosome, ensuring highly efficient energy transfer, is still not established experimentally. Here, we describe a mass spectrometry-based method that probes solvent-exposed surfaces of the FMO by labeling solvent-exposed aspartic and glutamic acid residues. The locations and extents of labeling of FMO on the native membrane in comparison with it alone and on a chlorosome-depleted membrane reveal the orientation. The large differences in the modification of certain peptides show that the Bchl a #3 side of the FMO trimer interacts with the CM, which is consistent with recent theoretical predictions. Moreover, the results also provide direct experimental evidence to confirm the overall architecture of the photosystem from Chlorobaculum tepidum (C. tepidum) and give information on the packing of the FMO protein in its native environment.

  16. Chlorobium aminolipid: a new membrane lipid from green sulfur bacteria

    SciTech Connect

    Olson, J.M.; Shaw, E.K.; Gaffney, J.S.; Scandella, C.J.

    1983-01-01

    A preliminary chemical characterization of the aminolipid from Chlorobium limicola f. thiosulfatophilum shows that this lipid contains no phosphorus, glycerol, sugar, ornithine or lysine. The lipid has an R/sub f/-value of 0.03 in chloroform-methanol-ammonia (13:5:1 v/v) on silica gel TLC plates. In chloroform-methanol-water (65:25:4) the R/sub f/- value is 0.16. The absorption spectrum indicates bands at 225 and 231 nm, and the fluorescence (maximum emission at 340 nm) shows excitation maxima at 232, 288, and approx. 325 nm. Acid hydrolysis of the lipid yields fluorescent substances A (ninhydrin positive) and B (negative) in addition to myristic acid (C 14:0). The fluorescence emission and excitation spectra of substance A are very similar to those of the intact lipid. Although these excitation spectra resemble the absorption spectra of 7,8-dihydropterins (bands at approx. 230, approx. 280, and 320-330 nm at pH 7), the weight of evidence appears to be against substance A being a pterin. Nevertheless the UV absorption and fluorescence spectra do indicate that the amino moiety (substance A) is an aromatic heterocyclic component.

  17. Unusually Stable Spinae from a Freshwater Chlorobium sp

    PubMed Central

    Brooke, J. S.; Koval, S. F.; Beveridge, T. J.

    1995-01-01

    A green Chlorobium sp. with spinae, strain JSB1, was isolated from an enrichment culture previously obtained from Fayetteville Green Lake, N.Y. (J. S. Brooke, J. B. Thompson, T. J. Beveridge, and S. F. Koval, Arch. Microbiol. 157:319-322, 1992). Cells were gram-negative, nonmotile rods which contained bacteriochlorophyll c and chlorosomes. Spinae were best seen by transmission electron microscopy in thin sections of cells fixed in the presence of tannic acid. High-resolution scanning electron microscopy showed the spinae randomly distributed at the cell surface and at the junctions between cells. Spinae were physically sheared from cells and isolated from the culture supernatant by ultrafiltration. As observed by electron microscopy, spinae demonstrated unusual structural stability when exposed for 1 h at 37 deg C to chemical treatments such as hydrogen bond-breaking agents, detergents, metal-chelating agents, proteases, and organic solvents. They were stable for 1 h at 37 deg C over the pH range 2.3 to 9.9 and in 1 M HCl and 1 M NaOH. The structural integrity of the spinae was also maintained when spinae were subjected to harsher treatments of autoclaving in 2% (wt/vol) sodium dodecyl sulfate and exposure to dithiothreitol at pH 9 for 1 h at 100 deg C. Partially dissociated spinae were obtained after 5 h at 100 deg C in 1 M HCl and 1 M NaOH. In acid, the tubular spinae became amorphous structures, with no helical striations visible. In alkali, the spinae had dissociated into irregular aggregates of disks. Since both high temperature and extremes of pH were required to achieve partial dissociation of the spinae, the strength of the structure presumably comes from covalent bonding. PMID:16534897

  18. Draft Genome Sequence of Lampenflora Chlorobium limicola Strain Frasassi in a Sulfidic Cave System.

    PubMed

    Mansor, Muammar; Macalady, Jennifer L

    2016-01-01

    The draft genome sequence of Chlorobium limicola strain Frasassi was assembled from metagenomic sequencing of a green mat in an artificially lighted aquarium inside the Frasassi caves in Italy. The genome is 2.08 Mbp in size and contains the necessary genes for anoxygenic photosynthesis and CO2 fixation. PMID:27174272

  19. Final Report - "CO2 Sequestration in Cell Biomass of Chlorobium Thiosulfatophilum"

    SciTech Connect

    James L. Gaddy, PhD; Ching-Whan Ko, PhD

    2009-05-04

    World carbon dioxide emissions from the combustion of fossil fuels have increased at a rate of about 3 percent per year during the last 40 years to over 24 billion tons today. While a number of methods have been proposed and are under study for dealing with the carbon dioxide problem, all have advantages as well as disadvantages which limit their application. The anaerobic bacterium Chlorobium thiosulfatophilum uses hydrogen sulfide and carbon dioxide to produce elemental sulfur and cell biomass. The overall objective of this project is to develop a commercial process for the biological sequestration of carbon dioxide and simultaneous conversion of hydrogen sulfide to elemental sulfur. The Phase I study successfully demonstrated the technical feasibility of utilizing this bacterium for carbon dioxide sequestration and hydrogen sulfide conversion to elemental sulfur by utilizing the bacterium in continuous reactor studies. Phase II studies involved an advanced research and development to develop the engineering and scale-up parameters for commercialization of the technology. Tasks include culture isolation and optimization studies, further continuous reactor studies, light delivery systems, high pressure studies, process scale-up, a market analysis and economic projections. A number of anaerobic and aerobic microorgansims, both non-photosynthetic and photosynthetic, were examined to find those with the fastest rates for detailed study to continuous culture experiments. C. thiosulfatophilum was selected for study to anaerobically produce sulfur and Thiomicrospira crunogena waws selected for study to produce sulfate non-photosynthetically. Optimal conditions for growth, H2S and CO2 comparison, supplying light and separating sulfur were defined. The design and economic projections show that light supply for photosynthetic reactions is far too expensive, even when solar systems are considered. However, the aerobic non-photosynthetic reaction to produce sulfate with T

  20. Structure analysis and comparative characterization of the cytochrome c' and flavocytochrome c from thermophilic purple photosynthetic bacterium Thermochromatium tepidum.

    PubMed

    Hirano, Yu; Kimura, Yukihiro; Suzuki, Hideaki; Miki, Kunio; Wang, Zheng-Yu

    2012-08-21

    The thermodynamic and spectroscopic properties of two soluble electron transport proteins, cytochrome (Cyt) c' and flavocytochrome c, isolated from thermophilic purple sulfur bacterium Thermochromatium (Tch.) tepidum were examined and compared with those of the corresponding proteins from a closely related mesophilic bacterium Allochromatium (Alc.) vinosum. These proteins share sequence identities of 82% for the cytochromes c' and 86% for the flavocytochromes c. Crystal structures of the two proteins have been determined at high resolutions. Differential scanning calorimetry and denaturing experiments show that both proteins from Tch. tepidum are thermally and structurally much more stable than their mesophilic counterparts. The denaturation temperature of Tch. tepidum Cyt c' was 22 °C higher than that of Alc. vinosum Cyt c', and the midpoints of denaturation using guanidine hydrochloride were 2.0 and 1.2 M for the Tch. tepidum and Alc. vinosum flavocytochromes c, respectively. The enhanced stabilities can be interpreted on the basis of the structural and sequence information obtained in this study: increased number of hydrogen bonds formed between main chain nitrogen and oxygen atoms, more compact structures and reduced number of glycine residues. Many residues with large side chains in Alc. vinosum Cyt c' are substituted by alanines in Tch. tepidum Cyt c'. Both proteins from Tch. tepidum exhibit high structural similarities to their counterparts from Alc. vinosum, and the different residues between the corresponding proteins are mainly located on the surface and exposed to the solvent. Water molecules are found in the heme vicinity of Tch. tepidum Cyt c' and form hydrogen bonds with the heme ligand and C-terminal charged residues. Similar bound waters are also found in the vicinity of one heme group in the diheme subunit of Tch. tepidum flavocytochrome c. Electron density map of the Tch. tepidum flavocytochrome c clearly revealed the presence of disulfur atoms

  1. In situ high-resolution structure of the baseplate antenna complex in Chlorobaculum tepidum.

    PubMed

    Nielsen, Jakob Toudahl; Kulminskaya, Natalia V; Bjerring, Morten; Linnanto, Juha M; Rätsep, Margus; Pedersen, Marie Østergaard; Lambrev, Petar H; Dorogi, Márta; Garab, Győző; Thomsen, Karen; Jegerschöld, Caroline; Frigaard, Niels-Ulrik; Lindahl, Martin; Nielsen, Niels Chr

    2016-01-01

    Photosynthetic antenna systems enable organisms harvesting light and transfer the energy to the photosynthetic reaction centre, where the conversion to chemical energy takes place. One of the most complex antenna systems, the chlorosome, found in the photosynthetic green sulfur bacterium Chlorobaculum (Cba.) tepidum contains a baseplate, which is a scaffolding super-structure, formed by the protein CsmA and bacteriochlorophyll a. Here we present the first high-resolution structure of the CsmA baseplate using intact fully functional, light-harvesting organelles from Cba. tepidum, following a hybrid approach combining five complementary methods: solid-state NMR spectroscopy, cryo-electron microscopy, isotropic and anisotropic circular dichroism and linear dichroism. The structure calculation was facilitated through development of new software, GASyCS for efficient geometry optimization of highly symmetric oligomeric structures. We show that the baseplate is composed of rods of repeated dimers of the strongly amphipathic CsmA with pigments sandwiched within the dimer at the hydrophobic side of the helix. PMID:27534696

  2. In situ high-resolution structure of the baseplate antenna complex in Chlorobaculum tepidum

    PubMed Central

    Nielsen, Jakob Toudahl; Kulminskaya, Natalia V.; Bjerring, Morten; Linnanto, Juha M.; Rätsep, Margus; Pedersen, Marie Østergaard; Lambrev, Petar H.; Dorogi, Márta; Garab, Győző; Thomsen, Karen; Jegerschöld, Caroline; Frigaard, Niels-Ulrik; Lindahl, Martin; Nielsen, Niels Chr.

    2016-01-01

    Photosynthetic antenna systems enable organisms harvesting light and transfer the energy to the photosynthetic reaction centre, where the conversion to chemical energy takes place. One of the most complex antenna systems, the chlorosome, found in the photosynthetic green sulfur bacterium Chlorobaculum (Cba.) tepidum contains a baseplate, which is a scaffolding super-structure, formed by the protein CsmA and bacteriochlorophyll a. Here we present the first high-resolution structure of the CsmA baseplate using intact fully functional, light-harvesting organelles from Cba. tepidum, following a hybrid approach combining five complementary methods: solid-state NMR spectroscopy, cryo-electron microscopy, isotropic and anisotropic circular dichroism and linear dichroism. The structure calculation was facilitated through development of new software, GASyCS for efficient geometry optimization of highly symmetric oligomeric structures. We show that the baseplate is composed of rods of repeated dimers of the strongly amphipathic CsmA with pigments sandwiched within the dimer at the hydrophobic side of the helix. PMID:27534696

  3. In situ high-resolution structure of the baseplate antenna complex in Chlorobaculum tepidum

    NASA Astrophysics Data System (ADS)

    Nielsen, Jakob Toudahl; Kulminskaya, Natalia V.; Bjerring, Morten; Linnanto, Juha M.; Rätsep, Margus; Pedersen, Marie Østergaard; Lambrev, Petar H.; Dorogi, Márta; Garab, Győző; Thomsen, Karen; Jegerschöld, Caroline; Frigaard, Niels-Ulrik; Lindahl, Martin; Nielsen, Niels Chr.

    2016-08-01

    Photosynthetic antenna systems enable organisms harvesting light and transfer the energy to the photosynthetic reaction centre, where the conversion to chemical energy takes place. One of the most complex antenna systems, the chlorosome, found in the photosynthetic green sulfur bacterium Chlorobaculum (Cba.) tepidum contains a baseplate, which is a scaffolding super-structure, formed by the protein CsmA and bacteriochlorophyll a. Here we present the first high-resolution structure of the CsmA baseplate using intact fully functional, light-harvesting organelles from Cba. tepidum, following a hybrid approach combining five complementary methods: solid-state NMR spectroscopy, cryo-electron microscopy, isotropic and anisotropic circular dichroism and linear dichroism. The structure calculation was facilitated through development of new software, GASyCS for efficient geometry optimization of highly symmetric oligomeric structures. We show that the baseplate is composed of rods of repeated dimers of the strongly amphipathic CsmA with pigments sandwiched within the dimer at the hydrophobic side of the helix.

  4. Triplet excited state spectra and dynamics of carotenoids from the thermophilic purple photosynthetic bacterium Thermochromatium tepidum

    SciTech Connect

    Niedzwiedzki, Dariusz; Kobayashi, Masayuki; Blankenship, R. E.

    2011-01-13

    Light-harvesting complex 2 from the anoxygenic phototrophic purple bacterium Thermochromatium tepidum was purified and studied by steady-state absorption, fluorescence and flash photolysis spectroscopy. Steady-state absorption and fluorescence measurements show that carotenoids play a negligible role as supportive energy donors and transfer excitation to bacteriochlorophyll-a with low energy transfer efficiency of ~30%. HPLC analysis determined that the dominant carotenoids in the complex are rhodopin and spirilloxanthin. Carotenoid excited triplet state formation upon direct (carotenoid) or indirect (bacteriochlorophyll-a Q{sub x} band) excitation shows that carotenoid triplets are mostly localized on spirilloxanthin. In addition, no triplet excitation transfer between carotenoids was observed. Such specific carotenoid composition and spectroscopic results strongly suggest that this organism optimized carotenoid composition in the light-harvesting complex 2 in order to maximize photoprotective capabilities of carotenoids but subsequently drastically suppressed their supporting role in light-harvesting process.

  5. Origin of bimodal fluorescence enhancement factors of Chlorobaculum tepidum reaction centers on silver island films.

    PubMed

    Maćkowski, Sebastian; Czechowski, Nikodem; Ashraf, Khuram U; Szalkowski, Marcin; Lokstein, Heiko; Cogdell, Richard J; Kowalska, Dorota

    2016-08-01

    We focus on the spectral dependence of plasmon-induced enhancement of fluorescence of Chlorobaculum tepidum reaction centers. When deposited on silver island film, they exhibit up to a 60-fold increase in fluorescence. The dependence of enhancement factors on the excitation wavelength is not correlated with the absorption spectrum of the plasmonic structure. In particular, the presence of one (or multiple) trimers of the Fenna-Matthews-Olson (FMO) protein reveals itself in bimodal distribution of enhancement factors for the excitation at 589 nm, the wavelength corresponding to bacteriochlorophyll absorption of FMO and the core of the RC. We conclude that the structure of multichromophoric complexes can substantially affect the impact of plasmonic excitations, which is important in the context of assembling functional biohybrid systems.

  6. Origin of bimodal fluorescence enhancement factors of Chlorobaculum tepidum reaction centers on silver island films.

    PubMed

    Maćkowski, Sebastian; Czechowski, Nikodem; Ashraf, Khuram U; Szalkowski, Marcin; Lokstein, Heiko; Cogdell, Richard J; Kowalska, Dorota

    2016-08-01

    We focus on the spectral dependence of plasmon-induced enhancement of fluorescence of Chlorobaculum tepidum reaction centers. When deposited on silver island film, they exhibit up to a 60-fold increase in fluorescence. The dependence of enhancement factors on the excitation wavelength is not correlated with the absorption spectrum of the plasmonic structure. In particular, the presence of one (or multiple) trimers of the Fenna-Matthews-Olson (FMO) protein reveals itself in bimodal distribution of enhancement factors for the excitation at 589 nm, the wavelength corresponding to bacteriochlorophyll absorption of FMO and the core of the RC. We conclude that the structure of multichromophoric complexes can substantially affect the impact of plasmonic excitations, which is important in the context of assembling functional biohybrid systems. PMID:27406896

  7. In situ solid-state NMR spectroscopy of protein in heterogeneous membranes: the baseplate antenna complex of Chlorobaculum tepidum.

    PubMed

    Kulminskaya, Natalia V; Pedersen, Marie Ø; Bjerring, Morten; Underhaug, Jarl; Miller, Mette; Frigaard, Niels-Ulrik; Nielsen, Jakob T; Nielsen, Niels Chr

    2012-07-01

    A clever combination: an in situ solid-state NMR analysis of CsmA proteins in the heterogeneous environment of the photoreceptor of Chlorobaculum tepidum is reported. Using different combinations of 2D and 3D solid-state NMR spectra, 90 % of the CsmA resonances are assigned and provide on the basis of chemical shift data information about the structure and conformation of CsmA in the CsmA-bacteriochlorophyll a complex.

  8. Measurement of photosynthesis using PAM technology in a purple sulfur bacterium Thermochromatium tepidum (Chromatiaceae).

    PubMed

    Ritchie, Raymond J; Mekjinda, Nutsara

    2015-01-01

    We demonstrate that Blue-diode-based pulse amplitude modulation (PAM) technology can be used to measure the photosynthetic electron transport rate (ETR) of purple sulfur bacteria (Thermochromatium tepidum, Chromatiaceae). Previous studies showed that PAM technology could be used to estimate photosynthesis in purple nonsulfur bacteria and so PAM technology can be used to estimate photosynthesis of both kinds of purple photosynthetic bacteria. The absorptance of Thermochromatium films on glass fiber disks was measured and used to calculate actual ETR. ETR vs Irradiance (P vs E) curves fitted the waiting-in-line model (ETR = (ETRmax × E/Eopt) × exp (1−E/Eopt)). Yield (Y) was only ≈ 0.3–0.4. Thermochromatium saturates at 325 ± 13.8 μmol photons m(−2) s(−1) or ≈15% sunlight and shows photoinhibition at high irradiances. A pond of Thermochromatium would exhibit classic surface inhibition. Photosynthesis is extremely low in the absence of an electron source: ETR increases in the presence of acetate (5 mol m(−3)) provided as an organic carbon source and also increases in the presence of sulfite (3 mol m(−3)) but not sulfide and is only marginally increased by the presence of Fe(2+). Nonphotochemical quenching does occur in Thermochromatium but at very low levels compared to oxygenic photo-organisms or Rhodopseudomonads. PMID:25932491

  9. Measurement of photosynthesis using PAM technology in a purple sulfur bacterium Thermochromatium tepidum (Chromatiaceae).

    PubMed

    Ritchie, Raymond J; Mekjinda, Nutsara

    2015-01-01

    We demonstrate that Blue-diode-based pulse amplitude modulation (PAM) technology can be used to measure the photosynthetic electron transport rate (ETR) of purple sulfur bacteria (Thermochromatium tepidum, Chromatiaceae). Previous studies showed that PAM technology could be used to estimate photosynthesis in purple nonsulfur bacteria and so PAM technology can be used to estimate photosynthesis of both kinds of purple photosynthetic bacteria. The absorptance of Thermochromatium films on glass fiber disks was measured and used to calculate actual ETR. ETR vs Irradiance (P vs E) curves fitted the waiting-in-line model (ETR = (ETRmax × E/Eopt) × exp (1−E/Eopt)). Yield (Y) was only ≈ 0.3–0.4. Thermochromatium saturates at 325 ± 13.8 μmol photons m(−2) s(−1) or ≈15% sunlight and shows photoinhibition at high irradiances. A pond of Thermochromatium would exhibit classic surface inhibition. Photosynthesis is extremely low in the absence of an electron source: ETR increases in the presence of acetate (5 mol m(−3)) provided as an organic carbon source and also increases in the presence of sulfite (3 mol m(−3)) but not sulfide and is only marginally increased by the presence of Fe(2+). Nonphotochemical quenching does occur in Thermochromatium but at very low levels compared to oxygenic photo-organisms or Rhodopseudomonads.

  10. Chlorobium limicola forma thiosulfatophilum: biocatalyst in the production of sulfur and organic carbon from a gas stream containing H/sub 2/O and CO/sub 2/

    SciTech Connect

    Cork, D.J.; Garunas, R.; Sajjad, A.

    1983-03-01

    Chlorobium limicola forma thiosulfatophilum (ATCC 17092) was grown in a 1-liter continuously stirred tank reactor (800-ml liquid volume) at pH 6.8, 30/sup 0/C, saturated light intensity, and gas flow rate of 23.6 ml/min from a gas cylinder blend consisting of 3.9 mol% H/sub 2/S, 9.2 mol% CO/sub 2/, 86.4 mol% N/sub 2/, and 0.5 mol% H/sub 2/. This is the first demonstration of photoautotrophic growth of a Chlorobium sp. on a continuous inorganic gas feed. A significant potential exists for applying this photoautotrophic process to desulfurization and CO/sub 2/ fixation of gases containing acidic components (H/sub 2/S and CO/sub 2/).

  11. Ultrafast time-resolved spectroscopy of the light-harvesting complex 2 (LH2) from the photosynthetic bacterium Thermochromatium tepidum

    SciTech Connect

    Niedzwiedzki, Dariusz M.; Fuciman, Marcel; Kobayashi, Masayuki; Frank, Harry A.; Blankenship, Robert E.

    2011-10-08

    The light-harvesting complex 2 from the thermophilic purple bacterium Thermochromatium tepidum was purified and studied by steady-state absorption and fluorescence, sub-nanosecond-time-resolved fluorescence and femtosecond time-resolved transient absorption spectroscopy. The measurements were performed at room temperature and at 10 K. The combination of both ultrafast and steady-state optical spectroscopy methods at ambient and cryogenic temperatures allowed the detailed study of carotenoid (Car)-to-bacteriochlorophyll (BChl) as well BChl-to-BChl excitation energy transfer in the complex. The studies show that the dominant Cars rhodopin (N = 11) and spirilloxanthin (N = 13) do not play a significant role as supportive energy donors for BChl a. This is related with their photophysical properties regulated by long π-electron conjugation. On the other hand, such properties favor some of the Cars, particularly spirilloxanthin (N = 13) to play the role of the direct quencher of the excited singlet state of BChl.

  12. The roles of C-terminal residues on the thermal stability and local heme environment of cytochrome c' from the thermophilic purple sulfur bacterium Thermochromatium tepidum.

    PubMed

    Kimura, Yukihiro; Kasuga, Sachiko; Unno, Masashi; Furusawa, Takashi; Osoegawa, Shinsuke; Sasaki, Yuko; Ohno, Takashi; Wang-Otomo, Zheng-Yu

    2015-04-01

    A soluble cytochrome (Cyt) c' from thermophilic purple sulfur photosynthetic bacterium Thermochromatium (Tch.) tepidum exhibits marked thermal tolerance compared with that from the closely related mesophilic counterpart Allochromatium vinosum. Here, we focused on the difference in the C-terminal region of the two Cyts c' and examined the effects of D131 and R129 mutations on the thermal stability and local heme environment of Cyt c' by differential scanning calorimetry (DSC) and resonance Raman (RR) spectroscopy. In the oxidized forms, D131K and D131G mutants exhibited denaturing temperatures significantly lower than that of the recombinant control Cyt c'. In contrast, R129K and R129A mutants denatured at nearly identical temperatures with the control Cyt c', indicating that the C-terminal D131 is an important residue maintaining the enhanced thermal stability of Tch. tepidum Cyt c'. The control Cyt c' and all of the mutants increased their thermal stability upon the reduction. Interestingly, D131K exhibited narrow DSC curves and unusual thermodynamic parameters in both redox states. The RR spectra of the control Cyt c' exhibited characteristic bands at 1,635 and 1,625 cm(-1), ascribed to intermediate spin (IS) and high spin (HS) states, respectively. The IS/HS distribution was differently affected by the D131 and R129 mutations and pH changes. Furthermore, R129 mutants suggested the lowering of their redox potentials. These results strongly indicate that the D131 and R129 residues play significant roles in maintaining the thermal stability and modulating the local heme environment of Tch. tepidum Cyt c'.

  13. Biosynthesis of bacteriochlorophyll c derivatives possessing chlorine and bromine atoms at the terminus of esterifying chains in the green sulfur bacterium Chlorobaculum tepidum.

    PubMed

    Saga, Yoshitaka; Hayashi, Keisuke; Mizoguchi, Tadashi; Tamiaki, Hitoshi

    2014-07-01

    The green sulfur photosynthetic bacterium Chlorobaculum tepidum newly produced BChl c derivatives possessing a chlorine or bromine atom at the terminus of the esterifying chain in the 17-propionate residue by cultivation with exogenous ω-halo-1-alkanols. The relative ratios of BChl c derivatives esterified with 8-chloro-1-octanol and 10-chloro-1-decanol were estimated to be 26.5% and 33.3% by cultivation with these ω-chloro-1-alkanols at the final concentrations of 300 and 150 μM, respectively. In contrast, smaller amounts of unnatural BChls c esterified with ω-bromo-1-alkanols were biosynthesized than those esterified with ω-chloro-1-alkanols: the ratios of BChl c derivatives esterified with 8-bromo-1-octanol and 10-bromo-1-decanol were 11.3% and 12.2% at the concentrations of 300 and 150 μM, respectively. These indicate that ω-chloro-1-alkanols can be incorporated into bacteriochlorophyllide c more than ω-bromo-1-alkanols in the BChl c biosynthetic pathway. The homolog compositions of the novel BChl c derivatives possessing a halogen atom were analogous to those of coexisting natural BChl c esterified with farnesol. These results demonstrate unique properties of BChl c synthase, BchK, which can utilize unnatural substrates containing halogen in the BChl c biosynthesis of Cba. tepidum.

  14. The origin of the unusual Qy red shift in LH1-RC complexes from purple bacteria Thermochromatium tepidum as revealed by Stark absorption spectroscopy.

    PubMed

    Ma, Fei; Yu, Long-Jiang; Wang-Otomo, Zheng-Yu; van Grondelle, Rienk

    2015-12-01

    Native LH1-RC of photosynthetic purple bacteria Thermochromatium (Tch.) tepidum, B915, has an ultra-red BChl a Qy absorption. Two blue-shifted complexes obtained by chemical modification, B893 and B882, have increasing full widths at half maximum (FWHM) and decreasing transition dipole oscillator strength. 77K Stark absorption spectroscopy studies were employed for the three complexes, trying to understand the origin of the 915 nm absorption. We found that Tr(∆α) and |∆μ| of both Qy and carotenoid (Car) bands are larger than for other purple bacterial LH complexes reported previously. Moreover, the red shifts of the Qy bands are associated with (1) increasing Tr(∆α) and |∆μ| of the Qy band, (2) the red shift of the Car Stark signal and (3) the increasing |∆μ| of the Car band. Based on the results and the crystal structure, a combined effect of exciton-charge transfer (CT) states mixing, and inhomogeneous narrowing of the BChl a site energy is proposed to be the origin of the 915 nm absorption. CT-exciton state mixing has long been found to be the origin of strong Stark signal in LH1 and special pair, and the more extent of the mixing in Tch. tepidum LH1 is mainly the consequence of the shorter BChl-BChl distances. The less flexible protein structure results in a smaller site energy disorder (inhomogeneous narrowing), which was demonstrated to be able to influence |∆μ| and absorption.

  15. Menaquinone-7 in the reaction center complex of the green sulfur bacterium Chlorobium vibrioforme functions as the electron acceptor A1.

    PubMed

    Kjaer, B; Frigaard, N U; Yang, F; Zybailov, B; Miller, M; Golbeck, J H; Scheller, H V

    1998-03-10

    Photosynthetically active reaction center complexes were prepared from the green sulfur bacterium Chlorobium vibrioforme NCIMB 8327, and the content of quinones was determined by extraction and high-performance liquid chromatography. The analysis showed a stoichiometry of 1.7 molecules of menaquinone-7/reaction center. No other quinones were detected in the isolated reaction centers, whereas membrane preparations also contained chlorobiumquinone. The possible involvement of quinones in electron transport was investigated by electron paramagnetic resonance (EPR) spectroscopy. A highly anisotropic radical was detected by Q-band EPR spectroscopy in both membranes and isolated reaction centers following dark reduction with sodium dithionite and photoaccumulation at 205 K. At 34 GHz, the EPR spectrum is characterized by a g tensor with gxx = 2.0063, gyy = 2.0052, gzz = 2.0020 and delta B of 0.7 mT, consistent with its identification as a quinone. This spectrum is highly similar in terms of g values and line widths to photoaccumulated A1- in photosystem I of Synechococcus sp. PCC 7002. The results indicate that menaquinone-7 in the green sulfur bacterial reaction center is analogous to phylloquinone in photosystem I.

  16. Dynamics of Energy and Electron Transfer in the FMO-Reaction Center Core Complex from the Phototrophic Green Sulfur Bacterium Chlorobaculum tepidum.

    PubMed

    He, Guannan; Niedzwiedzki, Dariusz M; Orf, Gregory S; Zhang, Hao; Blankenship, Robert E

    2015-07-01

    The reaction center core (RCC) complex and the RCC with associated Fenna-Matthews-Olson protein (FMO-RCC) complex from the green sulfur bacterium Chlorobaculum tepidum were studied comparatively by steady-state and time-resolved fluorescence (TRF) and femtosecond time-resolved transient absorption (TA) spectroscopies. The energy transfer efficiency from the FMO to the RCC complex was calculated to be ∼40% based on the steady-state fluorescence. TRF showed that most of the FMO complexes (66%), regardless of the fact that they were physically attached to the RCC, were not able to transfer excitation energy to the reaction center. The TA spectra of the RCC complex showed a 30-38 ps lifetime component regardless of the excitation wavelengths, which is attributed to charge separation. Excitonic equilibration was shown in TA spectra of the RCC complex when excited into the BChl a Qx band at 590 nm and the Chl a Qy band at 670 nm, while excitation at 840 nm directly populated the low-energy excited state and equilibration within the excitonic BChl a manifold was not observed. The TA spectra for the FMO-RCC complex excited into the BChl a Qx band could be interpreted by a combination of the excited FMO protein and RCC complex. The FMO-RCC complex showed an additional fast kinetic component compared with the FMO protein and the RCC complex, which may be due to FMO-to-RCC energy transfer.

  17. Calcium ions are involved in the unusual red shift of the light-harvesting 1 Qy transition of the core complex in thermophilic purple sulfur bacterium Thermochromatium tepidum.

    PubMed

    Kimura, Yukihiro; Hirano, Yu; Yu, Long-Jiang; Suzuki, Hiroaki; Kobayashi, Masayuki; Wang, Zheng-Yu

    2008-05-16

    Thermophilic purple sulfur bacterium, Thermochromatium tepidum, can grow at temperatures up to 58 degrees C and exhibits an unusual Qy absorption at 915 nm for the core light-harvesting complex (LH1), an approximately 35-nm red shift from those of its mesophilic counterparts. We demonstrate in this study, using a highly purified LH1-reaction center complex, that the LH1 Qy transition is strongly dependent on metal cations and Ca2+ is involved in the unusual red shift. Removal of the Ca2+ resulted in formation of a species with the LH1 Qy absorption at 880 nm, and addition of the Ca2+ to the 880-nm species recovered the native 915-nm form. Interchange between the two forms is fully reversible. Based on spectroscopic and isothermal titration calorimetry analyses, the Ca2+ binding to the LH1 complex was estimated to occur in a stoichiometric ratio of Ca2+/alphabeta-subunit = 1:1 and the binding constant was in 10(5) m(-1) order of magnitude, which is comparable with those for EF-hand Ca2+-binding proteins. Despite the high affinity, conformational changes in the LH1 complex upon Ca2+ binding were small and occurred slowly, with a typical time constant of approximately 6 min. Replacement of the Ca2+ with other metal cations caused blue shifts of the Qy bands depending on the property of the cations, indicating that the binding site is highly selective. Based on the amino acid sequences of the LH1 complex, possible Ca2+-binding sites are proposed that consist of several acidic amino acid residues near the membrane interfaces of the C-terminal region of the alpha-polypeptide and the N-terminal region of the beta-polypeptide.

  18. Temperature dependent LH1→RC energy transfer in purple bacteria Tch. tepidum with shiftable LH1-Qy band: A natural system to investigate thermally activated energy transfer in photosynthesis.

    PubMed

    Ma, Fei; Yu, Long-Jiang; Wang-Otomo, Zheng-Yu; van Grondelle, Rienk

    2016-04-01

    The native LH1-RC complex of the purple bacterium Thermochromatium (Tch.) tepidum has an ultra-red LH1-Qy absorption at 915nm, which can shift to 893 and 882nm by means of chemical modifications. These unique complexes are a good natural system to investigate the thermally activated energy transfer process, with the donor energies different while the other factors (such as the acceptor energy, special pair at 890nm, and the distance/relative orientation between the donor and acceptor) remain the same. The native B915-RC, B893-RC and B882-RC complexes, as well as the LH1-RC complex of Rhodobacter (Rba.) sphaeroides were studied by temperature-dependent time-resolved absorption spectroscopy. The energy transfer time constants, kET(-1), are 65, 45, 46 and 45ps at room temperature while 225, 58, 85, 33ps at 77K for the B915-RC, B893-RC, B882-RC and Rba. sphaeroides LH1-RC, respectively. The dependences of kET on temperature have different trends. The reorganization energies are determined to be 70, 290, 200 and 45cm(-1), respectively, by fitting kET vs temperature using Marcus equation. The activation energies are 200, 60, 115 and 20cm(-1), respectively. The influences of the structure (the arrangement of the 32 BChl a molecules) on kET are discussed based on these results, to reveal how the B915-RC complex accomplishes its energy transfer function with a large uphill energy of 290cm(-1).

  19. Biochemistry and control of the reductive tricarboxylic acid pathway of CO2 fixation and physiological role of the Rubis CO-like protein

    SciTech Connect

    Tabita, F. Robert

    2008-12-04

    During the past years of this project we have made progress relative to the two major goals of the proposal: (1) to study the biochemistry and regulation of the reductive TCA cycle of CO2 fixation and (2) to probe the physiological role of a RubisCO-like protein (RLP). Both studies primarily employ the green sulfur bacterium Chlorobium tepidum as well as other photosynthetic bacteria including Rhodospirillum rubrum and Rhodopseudomonas palustris.

  20. Influence of organics and silica on Fe(II) oxidation rates and cell-mineral aggregate formation by the green-sulfur Fe(II)-oxidizing bacterium Chlorobium ferrooxidans KoFox - Implications for Fe(II) oxidation in ancient oceans

    NASA Astrophysics Data System (ADS)

    Gauger, Tina; Byrne, James M.; Konhauser, Kurt O.; Obst, Martin; Crowe, Sean; Kappler, Andreas

    2016-06-01

    Most studies on microbial phototrophic Fe(II) oxidation (photoferrotrophy) have focused on purple bacteria, but recent evidence points to the importance of green-sulfur bacteria (GSB). Their recovery from modern ferruginous environments suggests that these photoferrotrophs can offer insights into how their ancient counterparts grew in Archean oceans at the time of banded iron formation (BIF) deposition. It is unknown, however, how Fe(II) oxidation rates, cell-mineral aggregate formation, and Fe-mineralogy vary under environmental conditions reminiscent of the geological past. To address this, we studied the Fe(II)-oxidizer Chlorobium ferrooxidans KoFox, a GSB living in co-culture with the heterotrophic Geospirillum strain KoFum. We investigated the mineralogy of Fe(III) metabolic products at low/high light intensity, and in the presence of dissolved silica and/or fumarate. Silica and fumarate influenced the crystallinity and particle size of the produced Fe(III) minerals. The presence of silica also enhanced Fe(II) oxidation rates, especially at high light intensities, potentially by lowering Fe(II)-toxicity to the cells. Electron microscopic imaging showed no encrustation of either KoFox or KoFum cells with Fe(III)-minerals, though weak associations were observed suggesting co-sedimentation of Fe(III) with at least some biomass via these aggregates, which could support diagenetic Fe(III)-reduction. Given that GSB are presumably one of the most ancient photosynthetic organisms, and pre-date cyanobacteria, our findings, on the one hand, strengthen arguments for photoferrotrophic activity as a likely mechanism for BIF deposition on a predominantly anoxic early Earth, but, on the other hand, also suggest that preservation of remnants of Fe(II)-oxidizing GSB as microfossils in the rock record is unlikely.

  1. Ultrafast absorption difference spectra of the Fenna-Matthews-Olson protein at 19 K: experiment and simulations.

    PubMed

    Buck, D R; Savikhin, S; Struve, W S

    1997-01-01

    We describe simulations of absorption difference spectra in strongly coupled photosynthetic antennas. In the presence of large resonance couplings, distinctive features arise from excited-state absorption transitions between one- and two-exciton levels. We first outline the theory for the heterodimer and for the general N-pigment system, and we demonstrate the transition between the strong and weak coupling regimes. The theory is applied to Fenna-Matthews-Olson (FMO) bacteriochlorophyll a protein trimers from the green photosynthetic bacterium Prosthecochloris aestuarii and then compared with experimental low-temperature absorption difference spectra of FMO trimers from the green bacterium Chlorobium tepidum.

  2. Chirality-Based Signatures of Local Protein Environments in Two-Dimensional Optical Spectroscopy of Two Species Photosynthetic Complexes of Green Sulfur Bacteria: Simulation Study

    PubMed Central

    Voronine, Dmitri V.; Abramavicius, Darius; Mukamel, Shaul

    2008-01-01

    Two-dimensional electronic chirality-induced signals of excitons in the photosynthetic Fenna-Matthews-Olson complex from two species of green sulfur bacteria (Chlorobium tepidum and Prosthecochloris aestuarii) are compared. The spectra are predicted to provide sensitive probes of local protein environment of the constituent bacteriochlorophyll a chromophores and reflect electronic structure variations (site energies and couplings) of the two complexes. Pulse polarization configurations are designed that can separate the coherent and incoherent exciton dynamics contributions to the two-dimensional spectra. PMID:18676650

  3. Software Comparison

    NASA Technical Reports Server (NTRS)

    Blanchard, D. C.

    1986-01-01

    Software Comparison Package (SCP) compares similar files. Normally, these are 90-character files produced by CDC UPDATE utility from program libraries that contain FORTRAN source code plus identifier. SCP also used to compare load maps, cross-reference outputs, and UPDATE corrections sets. Helps wherever line-by-line comparison of similarly structured files required.

  4. The Diversity of Sulfide Oxidation and Sulfate Reduction Genes Expressed by the Bacterial Communities of the Cariaco Basin, Venezuela.

    PubMed

    Rodriguez-Mora, Maria J; Edgcomb, Virginia P; Taylor, Craig; Scranton, Mary I; Taylor, Gordon T; Chistoserdov, Andrei Y

    2016-01-01

    Qualitative expression of dissimilative sulfite reductase (dsrA), a key gene in sulfate reduction, and sulfide:quinone oxidoreductase (sqr), a key gene in sulfide oxidation was investigated. Neither of the two could be amplified from mRNA retrieved with Niskin bottles but were amplified from mRNA retrieved by the Deep SID. The sqr and sqr-like genes retrieved from the Cariaco Basin were related to the sqr genes from a Bradyrhizobium sp., Methylomicrobium alcaliphilum, Sulfurovum sp. NBC37-1, Sulfurimonas autotrophica, Thiorhodospira sibirica and Chlorobium tepidum. The dsrA gene sequences obtained from the redoxcline of the Cariaco Basin belonged to chemoorganotrophic and chemoautotrophic sulfate and sulfur reducers belonging to the class Deltaproteobacteria (phylum Proteobacteria) and the order Clostridiales (phylum Firmicutes). PMID:27651847

  5. The Diversity of Sulfide Oxidation and Sulfate Reduction Genes Expressed by the Bacterial Communities of the Cariaco Basin, Venezuela

    PubMed Central

    Rodriguez-Mora, Maria J.; Edgcomb, Virginia P.; Taylor, Craig; Scranton, Mary I.; Taylor, Gordon T.; Chistoserdov, Andrei Y.

    2016-01-01

    Qualitative expression of dissimilative sulfite reductase (dsrA), a key gene in sulfate reduction, and sulfide:quinone oxidoreductase (sqr), a key gene in sulfide oxidation was investigated. Neither of the two could be amplified from mRNA retrieved with Niskin bottles but were amplified from mRNA retrieved by the Deep SID. The sqr and sqr-like genes retrieved from the Cariaco Basin were related to the sqr genes from a Bradyrhizobium sp., Methylomicrobium alcaliphilum, Sulfurovum sp. NBC37-1, Sulfurimonas autotrophica, Thiorhodospira sibirica and Chlorobium tepidum. The dsrA gene sequences obtained from the redoxcline of the Cariaco Basin belonged to chemoorganotrophic and chemoautotrophic sulfate and sulfur reducers belonging to the class Deltaproteobacteria (phylum Proteobacteria) and the order Clostridiales (phylum Firmicutes). PMID:27651847

  6. The Diversity of Sulfide Oxidation and Sulfate Reduction Genes Expressed by the Bacterial Communities of the Cariaco Basin, Venezuela

    PubMed Central

    Rodriguez-Mora, Maria J.; Edgcomb, Virginia P.; Taylor, Craig; Scranton, Mary I.; Taylor, Gordon T.; Chistoserdov, Andrei Y.

    2016-01-01

    Qualitative expression of dissimilative sulfite reductase (dsrA), a key gene in sulfate reduction, and sulfide:quinone oxidoreductase (sqr), a key gene in sulfide oxidation was investigated. Neither of the two could be amplified from mRNA retrieved with Niskin bottles but were amplified from mRNA retrieved by the Deep SID. The sqr and sqr-like genes retrieved from the Cariaco Basin were related to the sqr genes from a Bradyrhizobium sp., Methylomicrobium alcaliphilum, Sulfurovum sp. NBC37-1, Sulfurimonas autotrophica, Thiorhodospira sibirica and Chlorobium tepidum. The dsrA gene sequences obtained from the redoxcline of the Cariaco Basin belonged to chemoorganotrophic and chemoautotrophic sulfate and sulfur reducers belonging to the class Deltaproteobacteria (phylum Proteobacteria) and the order Clostridiales (phylum Firmicutes).

  7. Ultrafast absorption difference spectra of the Fenna-Matthews-Olson protein at 19 K: experiment and simulations.

    PubMed Central

    Buck, D R; Savikhin, S; Struve, W S

    1997-01-01

    We describe simulations of absorption difference spectra in strongly coupled photosynthetic antennas. In the presence of large resonance couplings, distinctive features arise from excited-state absorption transitions between one- and two-exciton levels. We first outline the theory for the heterodimer and for the general N-pigment system, and we demonstrate the transition between the strong and weak coupling regimes. The theory is applied to Fenna-Matthews-Olson (FMO) bacteriochlorophyll a protein trimers from the green photosynthetic bacterium Prosthecochloris aestuarii and then compared with experimental low-temperature absorption difference spectra of FMO trimers from the green bacterium Chlorobium tepidum. Images FIGURE 1 FIGURE 7 FIGURE 8 FIGURE 12 PMID:8994590

  8. Risk comparison

    SciTech Connect

    Coppola, A.; Hall, R.E.

    1981-02-01

    This report presents data for the comparison of societal risk from natural and man-made hazards. Only fatalities resulting from the hazards are used in the comparison, with the data and the comparative analysis taken from current literature. In comparing societal risks for most of the hazards, both expected values and frequency vs consequence curves are presented. For a subset of hazards, notably the power generation technologies (nuclear, coal, oil, and gas), which have not exhibited high consequence events (catastrophes), the comparisons are based on estimated expected values only. Individual risk data are presented in two ways, a probability of death within a year and the amount of life shortening of an average life span. 27 refs., 21 figs., 25 tabs.

  9. Characterization of an FMO Variant of Chlorobaculum tepidum Carrying Bacteriochlorophyll a Esterified by Geranylgeraniol

    SciTech Connect

    Wen, Jianzhong; Harada, Jiro; Buyle, Kenny; Yuan, Kevin; Tamiaki, Hitoshi; Oh-oka, Hirozo; Loomis, Richard A; Blankenship, R. E.

    2010-06-15

    The Fenna-Matthews-Olson light-harvesting antenna (FMO) protein has been a model system for understanding pigment-protein interactions in the energy transfer process in photosynthesis. All previous studies have utilized wild-type FMO proteins from several species. Here we report the purification and characterization of the first FMO protein variant generated via replacement of the esterifying alcohol at the C-17 propionate residue of bacteriochlorophyll (BChl) a, phytol, with geranylgeraniol, which possesses three more double bonds. The FMO protein still assembles with the modified pigment, but both the whole cell absorption and the biochemical purification indicate that the mutant cells contain a much less mature FMO protein. The gene expression was checked using qRT-PCR, and none of the genes encoding BChl a-binding proteins are strongly regulated at the transcriptional level. The smaller amount of the FMO protein in the mutant cell is probably due to the degradation of the apo-FMO protein at different stages after it does not bind the normal pigment. The absorption, fluorescence, and CD spectra of the purified FMO variant protein are similar to those of the wild-type FMO protein except the conformations of most pigments are more heterogeneous, which broadens the spectral bands. Interestingly, the lowest-energy pigment binding site seems to be unchanged and is the only peak that can be well resolved in 77 K absorption spectra. The excited-state lifetime of the variant FMO protein is unchanged from that of the wild type and shows a temperature-dependent modulation similar to that of the wild type. The variant FMO protein is less thermally stable than the wild type. The assembly of the FMO protein and also the implications of the decreased FMO/chlorosome stoichiometry are discussed in terms of the topology of these two antennas on the cytoplasmic membrane.

  10. Acquisition of Comparison Constructions

    ERIC Educational Resources Information Center

    Hohaus, Vera; Tiemann, Sonja; Beck, Sigrid

    2014-01-01

    This article presents a study on the time course of the acquisition of comparison constructions. The order in which comparison constructions (comparatives, measure phrases, superlatives, degree questions, etc.) show up in English- and German-learning children's spontaneous speech is quite fixed. It is shown to be insufficiently determined by…

  11. Theoretical Simulations and Ultrafast Pump-probe Spectroscopy Experiments in Pigment-protein Photosynthetic Complexes

    SciTech Connect

    Buck, D.R.

    2000-09-12

    Theoretical simulations and ultrafast pump-probe laser spectroscopy experiments were used to study photosynthetic pigment-protein complexes and antennae found in green sulfur bacteria such as Prosthecochloris aestuarii, Chloroflexus aurantiacus, and Chlorobium tepidum. The work focused on understanding structure-function relationships in energy transfer processes in these complexes through experiments and trying to model that data as we tested our theoretical assumptions with calculations. Theoretical exciton calculations on tubular pigment aggregates yield electronic absorption spectra that are superimpositions of linear J-aggregate spectra. The electronic spectroscopy of BChl c/d/e antennae in light harvesting chlorosomes from Chloroflexus aurantiacus differs considerably from J-aggregate spectra. Strong symmetry breaking is needed if we hope to simulate the absorption spectra of the BChl c antenna. The theory for simulating absorption difference spectra in strongly coupled photosynthetic antenna is described, first for a relatively simple heterodimer, then for the general N-pigment system. The theory is applied to the Fenna-Matthews-Olson (FMO) BChl a protein trimers from Prosthecochloris aestuarii and then compared with experimental low-temperature absorption difference spectra of FMO trimers from Chlorobium tepidum. Circular dichroism spectra of the FMO trimer are unusually sensitive to diagonal energy disorder. Substantial differences occur between CD spectra in exciton simulations performed with and without realistic inhomogeneous distribution functions for the input pigment diagonal energies. Anisotropic absorption difference spectroscopy measurements are less consistent with 21-pigment trimer simulations than 7-pigment monomer simulations which assume that the laser-prepared states are localized within a subunit of the trimer. Experimental anisotropies from real samples likely arise from statistical averaging over states with diagonal energies shifted by

  12. Exciton Theory for Supramolecular Chlorosomal Aggregates: 1. Aggregate Size Dependence of the Linear Spectra

    PubMed Central

    Prokhorenko, V. I.; Steensgaard, D. B.; Holzwarth, A. R.

    2003-01-01

    The interior of chlorosomes of green bacteria forms an unusual antenna system organized without proteins. The steady-spectra (absorption, circular dichroism, and linear dichroism) have been modeled using the Frenkel Hamiltonian for the large tubular aggregates of bacteriochlorophylls with geometries corresponding to those proposed for Chloroflexus aurantiacus and Chlorobium tepidum chlorosomes. For the Cf. aurantiacus aggregates we apply a structure used previously (V. I. Prokhorenko., D. B. Steensgaard, and A. R. Holzwarth, Biophys. J. 2000, 79:2105–2120), whereas for the Cb. tepidum aggregates a new extended model of double-tube aggregates, based on recently published solid-state nuclear magnetic resonance studies (B.-J. van Rossum, B. Y. van Duhl, D. B. Steensgaard, T. S. Balaban, A. R. Holzwarth, K. Schaffner, and H. J. M. de Groot, Biochemistry 2001, 40:1587–1595), is developed. We find that the circular dichroism spectra depend strongly on the aggregate length for both types of chlorosomes. Their shape changes from “type-II” (negative at short wavelengths to positive at long wavelengths) to the “mixed-type” (negative-positive-negative) in the nomenclature proposed in K. Griebenow, A. R. Holzwarth, F. van Mourik, and R. van Grondelle, Biochim. Biophys. Acta 1991, 1058:194–202, for an aggregate length of 30–40 bacteriochlorophyll molecules per stack. This “size effect” on the circular dichroism spectra is caused by appearance of macroscopic chirality due to circular distribution of the transition dipole moment of the monomers. We visualize these distributions, and also the corresponding Frenkel excitons, using a novel presentation technique. The observed size effects provide a key to explain many previously puzzling and seemingly contradictory experimental data in the literature on the circular and linear dichroism spectra of seemingly identical types of chlorosomes. PMID:14581217

  13. Redox regulation of energy transfer efficiency in antennas of green photosynthetic bacteria

    NASA Technical Reports Server (NTRS)

    Blankenship, R. E.; Cheng, P.; Causgrove, T. P.; Brune, D. C.; Wang, J.

    1993-01-01

    The efficiency of energy transfer from the peripheral chlorosome antenna structure to the membrane-bound antenna in green sulfur bacteria depends strongly on the redox potential of the medium. The fluorescence spectra and lifetimes indicate that efficient quenching pathways are induced in the chlorosome at high redox potential. The midpoint redox potential for the induction of this effect in isolated chlorosomes from Chlorobium vibrioforme is -146 mV at pH 7 (vs the normal hydrogen electrode), and the observed midpoint potential (n = 1) decreases by 60 mV per pH unit over the pH range 7-10. Extraction of isolated chlorosomes with hexane has little effect on the redox-induced quenching, indicating that the component(s) responsible for this effect are bound and not readily extractable. We have purified and partially characterized the trimeric water-soluble bacteriochlorophyll a-containing protein from the thermophilic green sulfur bacterium Chlorobium tepidum. This protein is located between the chlorosome and the membrane. Fluorescence spectra of the purified protein indicate that it also contains groups that quench excitations at high redox potential. The results indicate that the energy transfer pathway in green sulfur bacteria is regulated by redox potential. This regulation appears to operate in at least two distinct places in the energy transfer pathway, the oligomeric pigments in the interior of the chlorosome and in the bacteriochlorophyll a protein. The regulatory effect may serve to protect the cell against superoxide-induced damage when oxygen is present. By quenching excitations before they reach the reaction center, reduction and subsequent autooxidation of the low potential electron acceptors found in these organisms is avoided.

  14. Modelling the bacterial photosynthetic reaction center. V. Assignment of the electronic transition observed at 2200 cm-1 in the special-pair radical-cation as a second-highest occupied molecular orbital to highest occupied molecular orbital transition

    NASA Astrophysics Data System (ADS)

    Reimers, Jeffrey R.; Shapley, Warwick A.; Hush, Noel S.

    2003-08-01

    Primary charge separation in photoexcited photosynthetic reaction centers produces the radical cation P+ of a bacteriochlorophyll dimer known as the special-pair P. P+ has an intense electronic transition in the vicinity of 1800-5000 cm-1 which is usually assigned to the interchromophore hole-transfer excitation of the dimer radical cation; in principle, this spectrum can give much insight into key steps of the solar-to-electrical energy-conversion process. The extent to which this transition is localized on one-half of the dimer or delocalized over both is of utmost importance; an authoritative deduction of this quantity from purely spectroscopic arguments requires the detailed assignment of the observed high to medium resolution spectra. For reaction centers containing bacteriochlorophylls a or b, a shoulder is observed at 2200 cm-1 on the low-energy side of the main hole-transfer absorption band, a band whose maximum is near 2700 cm-1. Before quantitative analysis of the hole-transfer absorption in these well-studied systems can be attempted, the nature of the processes leading to this shoulder must be determined. We interpret it as arising from an intrachromophore SHOMO to HOMO transition whose intensity arises wholly through vibronic coupling with the hole-transfer band. A range of ab initio and density-functional calculations are performed to estimate the energy of this transition both for monomeric cations and for P+ of Blastochloris viridis, Rhodobacter sphaeroides, Chlorobium limicola, Chlorobium tepidum, Chlamydomonas reinhardtii, Synochocystis S.6803, spinach photosystems I and II, Heliobacillus mobilis, and finally Heliobacterium modesticaldum, with the results found to qualitatively describe the available experimental data. Subsequent papers in this series provide quantitative analyses of the vibronic coupling and complete spectral simulations based on the model developed herein.

  15. Redox regulation of energy transfer efficiency in antennas of green photosynthetic bacteria.

    PubMed

    Blankenship, R E; Cheng, P; Causgrove, T P; Brune, D C; Wang SH-H; Choh J-U; Wang, J

    1993-01-01

    The efficiency of energy transfer from the peripheral chlorosome antenna structure to the membrane-bound antenna in green sulfur bacteria depends strongly on the redox potential of the medium. The fluorescence spectra and lifetimes indicate that efficient quenching pathways are induced in the chlorosome at high redox potential. The midpoint redox potential for the induction of this effect in isolated chlorosomes from Chlorobium vibrioforme is -146 mV at pH 7 (vs the normal hydrogen electrode), and the observed midpoint potential (n = 1) decreases by 60 mV per pH unit over the pH range 7-10. Extraction of isolated chlorosomes with hexane has little effect on the redox-induced quenching, indicating that the component(s) responsible for this effect are bound and not readily extractable. We have purified and partially characterized the trimeric water-soluble bacteriochlorophyll a-containing protein from the thermophilic green sulfur bacterium Chlorobium tepidum. This protein is located between the chlorosome and the membrane. Fluorescence spectra of the purified protein indicate that it also contains groups that quench excitations at high redox potential. The results indicate that the energy transfer pathway in green sulfur bacteria is regulated by redox potential. This regulation appears to operate in at least two distinct places in the energy transfer pathway, the oligomeric pigments in the interior of the chlorosome and in the bacteriochlorophyll a protein. The regulatory effect may serve to protect the cell against superoxide-induced damage when oxygen is present. By quenching excitations before they reach the reaction center, reduction and subsequent autooxidation of the low potential electron acceptors found in these organisms is avoided.

  16. Public opinion: Country comparisons

    NASA Astrophysics Data System (ADS)

    Hopkins, Debbie

    2015-11-01

    Climate change awareness, risk perception and policy support vary between and within countries. National-scale comparisons can help to explain this variability and be used to develop targeted interventions.

  17. 1997 MWD comparison tables

    SciTech Connect

    Wiseman, K.

    1997-05-01

    This year`s MWD Comparison Tables include a Quick Reference Guide listing MWD sensors by collar size for each manufacturer. Following the Quick Reference Guide are the comparison tables, which list general, directional, gamma ray, resistivity, density and neutron data for each tool. The MWD Tables should only be used as a reference source. System specifications frequently change as tools are refined and developed. Consult MWD marketing representatives prior to making final tool selections. A contact key for all the companies listed in the tables appears on the last page.

  18. Fall 2013 International Comparisons

    ERIC Educational Resources Information Center

    Northwest Evaluation Association, 2014

    2014-01-01

    This Fall report is an aggregated statistical analysis of Measures of Academic Progress® (MAP®) data from international schools. The report provides a consistent means of comparisons of specific sub-groups by subject and grade, which allows partners to compare their MAP® results with other schools within their region or membership organization.…

  19. Spring 2013 International Comparisons

    ERIC Educational Resources Information Center

    Northwest Evaluation Association, 2013

    2013-01-01

    This report is an aggregated statistical analysis of Measures of Academic Progress® (MAP®) data from international schools. The report provides a consistent means of comparisons of specific sub-groups by subject and grade, which allows partners to compare their MAP® results with other schools within their region or membership organization. There…

  20. Motives for Social Comparison.

    ERIC Educational Resources Information Center

    Helgeson, Vicki S.; Mickelson, Kristin D.

    1995-01-01

    A set of motive statements for social comparison was elicited from one group of subjects and then rated in terms of usefulness by a second group of subjects. Analysis of these statements revealed six motives in response to two different hypothetical scenarios: self-evaluation, common bond, self-improvement, self-enhancement, altruism, and…

  1. Comparison of five benchmarks

    SciTech Connect

    Huss, J. E.; Pennline, J. A.

    1987-02-01

    Five benchmark programs were obtained and run on the NASA Lewis CRAY X-MP/24. A comparison was made between the programs codes and between the methods for calculating performance figures. Several multitasking jobs were run to gain experience in how parallel performance is measured.

  2. 1996 MWD comparison tables

    SciTech Connect

    Gastineau, J.

    1996-05-01

    Petroleum Engineer International`s ninth annual Measurement While Drilling Tables compare the different operating capabilities of survey and logging tools from 13 MWD vendors. This year`s MWD Comparison Tables include a Quick Reference Guide listing MWD sensors by collar size for each manufacturer. Following the Quick Reference Guide are the comparison tables, listing general, directional, gamma ray, resistivity, density and neutron data for each tool. The MWD Tables should serve only as a reference source. System specifications can change rapidly as tools are refined and developed. Consultation with MWD marketing representatives before making a final tool selection is recommended. A contact key for all of the companies listed in the tables is provided.

  3. Phylobiochemical characterization of class-Ib aspartate/prephenate aminotransferases reveals evolution of the plant arogenate phenylalanine pathway.

    PubMed

    Dornfeld, Camilla; Weisberg, Alexandra J; K C, Ritesh; Dudareva, Natalia; Jelesko, John G; Maeda, Hiroshi A

    2014-07-01

    The aromatic amino acid Phe is required for protein synthesis and serves as the precursor of abundant phenylpropanoid plant natural products. While Phe is synthesized from prephenate exclusively via a phenylpyruvate intermediate in model microbes, the alternative pathway via arogenate is predominant in plant Phe biosynthesis. However, the molecular and biochemical evolution of the plant arogenate pathway is currently unknown. Here, we conducted phylogenetically informed biochemical characterization of prephenate aminotransferases (PPA-ATs) that belong to class-Ib aspartate aminotransferases (AspAT Ibs) and catalyze the first committed step of the arogenate pathway in plants. Plant PPA-ATs and succeeding arogenate dehydratases (ADTs) were found to be most closely related to homologs from Chlorobi/Bacteroidetes bacteria. The Chlorobium tepidum PPA-AT and ADT homologs indeed efficiently converted prephenate and arogenate into arogenate and Phe, respectively. A subset of AspAT Ib enzymes exhibiting PPA-AT activity was further identified from both Plantae and prokaryotes and, together with site-directed mutagenesis, showed that Thr-84 and Lys-169 play key roles in specific recognition of dicarboxylic keto (prephenate) and amino (aspartate) acid substrates. The results suggest that, along with ADT, a gene encoding prephenate-specific PPA-AT was transferred from a Chlorobi/Bacteroidetes ancestor to a eukaryotic ancestor of Plantae, allowing efficient Phe and phenylpropanoid production via arogenate in plants today.

  4. The cyanobacterial genome core and the origin of photosynthesis

    PubMed Central

    Mulkidjanian, Armen Y.; Koonin, Eugene V.; Makarova, Kira S.; Mekhedov, Sergey L.; Sorokin, Alexander; Wolf, Yuri I.; Dufresne, Alexis; Partensky, Frédéric; Burd, Henry; Kaznadzey, Denis; Haselkorn, Robert; Galperin, Michael Y.

    2006-01-01

    Comparative analysis of 15 complete cyanobacterial genome sequences, including “near minimal” genomes of five strains of Prochlorococcus spp., revealed 1,054 protein families [core cyanobacterial clusters of orthologous groups of proteins (core CyOGs)] encoded in at least 14 of them. The majority of the core CyOGs are involved in central cellular functions that are shared with other bacteria; 50 core CyOGs are specific for cyanobacteria, whereas 84 are exclusively shared by cyanobacteria and plants and/or other plastid-carrying eukaryotes, such as diatoms or apicomplexans. The latter group includes 35 families of uncharacterized proteins, which could also be involved in photosynthesis. Only a few components of cyanobacterial photosynthetic machinery are represented in the genomes of the anoxygenic phototrophic bacteria Chlorobium tepidum, Rhodopseudomonas palustris, Chloroflexus aurantiacus, or Heliobacillus mobilis. These observations, coupled with recent geological data on the properties of the ancient phototrophs, suggest that photosynthesis originated in the cyanobacterial lineage under the selective pressures of UV light and depletion of electron donors. We propose that the first phototrophs were anaerobic ancestors of cyanobacteria (“procyanobacteria”) that conducted anoxygenic photosynthesis using a photosystem I-like reaction center, somewhat similar to the heterocysts of modern filamentous cyanobacteria. From procyanobacteria, photosynthesis spread to other phyla by way of lateral gene transfer. PMID:16924101

  5. Fructose-1,6-bisphosphate aldolases in amitochondriate protists constitute a single protein subfamily with eubacterial relationships.

    PubMed

    Sánchez, Lidya; Horner, David; Moore, Dorothy; Henze, Katrin; Embley, T; Müller, Miklós

    2002-07-24

    Sequences of putative fructose-1,6-bisphospate aldolases (FBA) in five amitochondriate unicellular eukaryotes, the diplomonads Giardia intestinalis (published earlier) and Spironucleus barkhanus, the pelobiont Mastigamoeba balamuthi,the entamoebid Entamoeba histolytica, and the parabasalid Trichomonas vaginalis all belong to Class II of FBAs and are highly similar to each other (>48% amino acid identity). The five protist sequences, however, do not form a monophyletic group. Diplomonad FBAs share a most recent common ancestor, while FBAs of the three other protist species are part of a lineage that also includes sequences from a few eubacteria (Clostridium difficile, Treponema pallidum, Chlorobium tepidum). Both clades are part of the Type B of Class II aldolases, a complex that contains at least three additional lineages (subgroups) of enzymes. Type B enzymes are distant from Type A Class II aldolases, which consists of a number of bacterial and fungal enzymes and also contains the cytosolic FBA of Euglena gracilis. Class II aldolases are not homologous to Class I enzymes, to which animal and plant enzymes belong. The results indicate that amitochondriate protists acquired their FBAs from separate and different sources, involving lateral gene transfer from eubacteria, than did all other eukaryotes studied so far and underscore the complex composition of the glycolytic machinery in unicellular eukaryotes.

  6. Retained gas inventory comparison

    SciTech Connect

    BARTON, W.B.

    1999-05-18

    Gas volume data derived from four different analytical methods were collected and analyzed for comparison to volumes originally used in the technical basis for the Basis for Interim Operations (BIO). The original volumes came from Hodgson (1996) listed in the reference section of this document. Hodgson (1996) screened all 177 single and double-shell tanks for the presence of trapped gas in waste via two analytical methods: Surface Level Rise (SLR), and Barometric Pressure Effect (BPE). More recent gas volume projections have been calculated using different analytical techniques along with updates to the parameters used as input to the SLR and BPE models. Gas volumes derived from new analytical instruments include those as measured by the Void Fraction Instrument (VFI) and Retained Gas Sampler (RGS). The results of this comparison demonstrate that the original retained gas volumes of Hodgson (1996) used as a technical basis in developing the BIO were conservative, and were conservative from a safety analysis standpoint. These results represent only comparisons to the original reported volumes using the limited set of newly acquired data that is available.

  7. NTP comparison process

    NASA Technical Reports Server (NTRS)

    Corban, Robert

    1993-01-01

    The systems engineering process for the concept definition phase of the program involves requirements definition, system definition, and consistent concept definition. The requirements definition process involves obtaining a complete understanding of the system requirements based on customer needs, mission scenarios, and nuclear thermal propulsion (NTP) operating characteristics. A system functional analysis is performed to provide a comprehensive traceability and verification of top-level requirements down to detailed system specifications and provides significant insight into the measures of system effectiveness to be utilized in system evaluation. The second key element in the process is the definition of system concepts to meet the requirements. This part of the process involves engine system and reactor contractor teams to develop alternative NTP system concepts that can be evaluated against specific attributes, as well as a reference configuration against which to compare system benefits and merits. Quality function deployment (QFD), as an excellent tool within Total Quality Management (TQM) techniques, can provide the required structure and provide a link to the voice of the customer in establishing critical system qualities and their relationships. The third element of the process is the consistent performance comparison. The comparison process involves validating developed concept data and quantifying system merits through analysis, computer modeling, simulation, and rapid prototyping of the proposed high risk NTP subsystems. The maximum amount possible of quantitative data will be developed and/or validated to be utilized in the QFD evaluation matrix. If upon evaluation of a new concept or its associated subsystems determine to have substantial merit, those features will be incorporated into the reference configuration for subsequent system definition and comparison efforts.

  8. NTP comparison process

    NASA Astrophysics Data System (ADS)

    Corban, Robert

    The systems engineering process for the concept definition phase of the program involves requirements definition, system definition, and consistent concept definition. The requirements definition process involves obtaining a complete understanding of the system requirements based on customer needs, mission scenarios, and nuclear thermal propulsion (NTP) operating characteristics. A system functional analysis is performed to provide a comprehensive traceability and verification of top-level requirements down to detailed system specifications and provides significant insight into the measures of system effectiveness to be utilized in system evaluation. The second key element in the process is the definition of system concepts to meet the requirements. This part of the process involves engine system and reactor contractor teams to develop alternative NTP system concepts that can be evaluated against specific attributes, as well as a reference configuration against which to compare system benefits and merits. Quality function deployment (QFD), as an excellent tool within Total Quality Management (TQM) techniques, can provide the required structure and provide a link to the voice of the customer in establishing critical system qualities and their relationships. The third element of the process is the consistent performance comparison. The comparison process involves validating developed concept data and quantifying system merits through analysis, computer modeling, simulation, and rapid prototyping of the proposed high risk NTP subsystems. The maximum amount possible of quantitative data will be developed and/or validated to be utilized in the QFD evaluation matrix. If upon evaluation of a new concept or its associated subsystems determine to have substantial merit, those features will be incorporated into the reference configuration for subsequent system definition and comparison efforts.

  9. MACPEX Water Measurement Comparison

    NASA Astrophysics Data System (ADS)

    Al-Saadi, J. A.; Thornhill, A.; Alston, E. J.; Chen, G.; Fahey, D. W.; Jensen, E. J.; Mace, G. G.

    2012-12-01

    The Mid-latitude Airborne Cirrus Properties Experiment (MACPEX) airborne field campaign was conducted in March and April 2011 to investigate cirrus cloud properties and the processes that affect their impact on radiation. In pursuit of this goal the NASA WB-57 was outfitted with dozens of in-situ instruments from government and university science teams including a wide range of water instruments. This provided an unprecedented situation to compare eight water instruments on one platform measuring water vapor (CIMS, DLH, HWV, JLH, and ULH), total water (ALIAS and FISH) and ice water content (CLH/IWC) for 14 flight days. Objective and data-driven approaches were applied to analyze the comparison data and to assess the consistency levels between the instruments and instrument uncertainties. The analysis is primarily focused on the upper tropospheric and lower stratospheric conditions, paying particular attention to water levels below 20 ppmv and between 20 - 120 ppmv depending on specific instrument data coverage. To be presented are comparison results suggesting the level of the agreement among the instrument as a function of atmospheric conditions, e.g., temperature and water vapor. Also discussed are some exploratory analyses of instrument precisions.

  10. Notes on the Comparison Class

    NASA Astrophysics Data System (ADS)

    Solt, Stephanie

    This paper investigates the role of comparison classes in the semantics of gradable adjectives in the positive form, focusing on the case where the comparison class is expressed overtly via a for-phrase (e.g. John is tall for a jockey). Two central questions are addressed: what information does the comparison class provide, and how is this information integrated compositionally? It is shown that the standard of comparison invoked by the positive form can be analyzed as a range of values whose width is based on the degree of dispersion in the comparison class. Compositionally, the comparison class can be analyzed as an argument of a null positive morpheme (contra Kennedy [13]), in parallel to recent proposals for the superlative (e.g. Heim [9]). The implications of the analysis for the choice between degree- and delineation-based analyses of gradable adjectives are discussed.

  11. Long History of IAM Comparisons

    SciTech Connect

    Smith, Steven J.; Clarke, Leon E.; Edmonds, James A.; Kejun, Jiang; Kriegler, Elmar; Masui, Toshihiko; Riahi, Keywan; Shukla, Priyadarshi R.; Tavoni, Massimo; Van Vuuren, Detlef; Weyant, John

    2015-04-23

    Correspondence to editor: We agree with the editors that the assumptions behind models of all types, including integrated assessment models (IAMs), should be as transparent as possible. The editors were in error, however, when they implied that the IAM community is just “now emulating the efforts of climate researchers by instigating their own model inter-comparison projects (MIPs).” In fact, model comparisons for integrated assessment and climate models followed a remarkably similar trajectory. Early General Circulation Model (GCM) comparison efforts, evolved to the first Atmospheric Model Inter-comparison Project (AMIP), which was initiated in the early 1990s. Atmospheric models evolved to coupled atmosphere-ocean models (AOGCMs) and results from the first Coupled Model Inter-Comparison Project (CMIP1) become available about a decade later. Results of first energy model comparison exercise, conducted under the auspices of the Stanford Energy Modeling Forum, were published in 1977. A summary of the first comparison focused on climate change was published in 1993. As energy models were coupled to simple economic and climate models to form IAMs, the first comparison exercise for IAMs (EMF-14) was initiated in 1994, and IAM comparison exercises have been on-going since this time.

  12. Geology orbiter comparison study

    NASA Technical Reports Server (NTRS)

    Cutts, J. A. J.; Blasius, K. R.; Davis, D. R.; Pang, K. D.; Shreve, D. C.

    1977-01-01

    Instrument requirements of planetary geology orbiters were examined with the objective of determining the feasibility of applying standard instrument designs to a host of terrestrial targets. Within the basic discipline area of geochemistry, gamma-ray, X-ray fluorescence, and atomic spectroscopy remote sensing techniques were considered. Within the discipline area of geophysics, the complementary techniques of gravimetry and radar were studied. Experiments using these techniques were analyzed for comparison at the Moon, Mercury, Mars and the Galilean satellites. On the basis of these comparative assessments, the adaptability of each sensing technique was judged as a basic technique for many targets, as a single instrument applied to many targets, as a single instrument used in different mission modes, and as an instrument capability for nongeoscience objectives.

  13. Glovebox decontamination technology comparison

    SciTech Connect

    Quintana, D.M.; Rodriguez, J.B.; Cournoyer, M.E.

    1999-09-26

    Reconfiguration of the CMR Building and TA-55 Plutonium Facility for mission requirements will require the disposal or recycle of 200--300 gloveboxes or open front hoods. These gloveboxes and open front hoods must be decontaminated to meet discharge limits for Low Level Waste. Gloveboxes and open front hoods at CMR have been painted. One of the deliverables on this project is to identify the best method for stripping the paint from large numbers of gloveboxes. Four methods being considered are the following: conventional paint stripping, dry ice pellets, strippable coatings, and high pressure water technology. The advantages of each technology will be discussed. Last, cost comparisons between the technologies will be presented.

  14. 1994 MWD comparison tables

    SciTech Connect

    Not Available

    1994-05-01

    Twenty-eight measurement while drilling tools are listed in this year's MWD Comparison Tables. Updated data on tools listed last year and data on five new tools provide a convenient guide for choosing MWD systems. Future MWD technologies include sonic tools and tools that make measurements ahead of the bit. For the seventh year, Petroleum Engineer International presents the Measurement While Drilling (MWD) Tables comparing a variety of available tools from many different vendors. The 1994 Tables include two additional companies and five new MWD tools not found in last year's Tables. However, the tables should serve only as a reference source. System specifications can change rapidly as tools are refined and new technologies develop. Operators and contractors should consult designated MWD marketing representatives before making a final tool selection.

  15. Social Comparison Processes in Organizations

    ERIC Educational Resources Information Center

    Greenberg, Jerald; Ashton-James, Claire E.; Ashkanasy, Neal M.

    2007-01-01

    We systematically analyze the role of social comparison processes in organizations. Specifically, we describe how social comparison processes have been used to explain six key areas of organizational inquiry: (1) organizational justice, (2) performance appraisal, (3) virtual work environments, (4) affective behavior in the workplace, (5) stress,…

  16. Social Comparison in the Classroom: A Review

    ERIC Educational Resources Information Center

    Dijkstra, Pieternel; Kuyper, Hans; van der Werf, Greetje; Buunk, Abraham P.; van der Zee, Yvonne G.

    2008-01-01

    This article reviews research conducted on social comparison processes in the classroom since Festinger proposed his theory of social comparison. It covers the theoretical framework of social comparison theory, and it is organized around the following themes: motives for social comparison, dimensions of social comparison, direction of social…

  17. Indirect comparisons of therapeutic interventions

    PubMed Central

    Schöttker, Ben; Lühmann, Dagmar; Boulkhemair, Dalila; Raspe, Heiner

    2009-01-01

    Health political background The comparison of the effectiveness of health technologies is not only laid down in German law (Social Code Book V, § 139 and § 35b) but also constitutes a central element of clinical guidelines and decision making in health care. Tools supporting decision making (e. g. Health Technology Assessments (HTA)) are therefore in need of a valid methodological repertoire for these comparisons. Scientific background Randomised controlled head-to-head trials which directly compare the effects of different therapies are considered the gold standard methodological approach for the comparison of the efficacy of interventions. Because this type of trial is rarely found, comparisons of efficacy often need to rely on indirect comparisons whose validity is being controversially debated. Research questions Research questions for the current assessment are: Which (statistical) methods for indirect comparisons of therapeutic interventions do exist, how often are they applied and how valid are their results in comparison to the results of head-to-head trials? Methods In a systematic literature research all medical databases of the German Institute of Medical Documentation and Information (DIMDI) are searched for methodological papers as well as applications of indirect comparisons in systematic reviews. Results of the literature analysis are summarized qualitatively for the characterisation of methods and quantitatively for the frequency of their application. The validity of the results from indirect comparisons is checked by comparing them to the results from the gold standard – a direct comparison. Data sets from systematic reviews which use both direct and indirect comparisons are tested for consistency by of the z-statistic. Results 29 methodological papers and 106 applications of indirect methods in systematic reviews are being analysed. Four methods for indirect comparisons can be identified: Unadjusted indirect comparisons include, independent of

  18. Data storage technology comparisons

    NASA Technical Reports Server (NTRS)

    Katti, Romney R.

    1990-01-01

    The role of data storage and data storage technology is an integral, though conceptually often underestimated, portion of data processing technology. Data storage is important in the mass storage mode in which generated data is buffered for later use. But data storage technology is also important in the data flow mode when data are manipulated and hence required to flow between databases, datasets and processors. This latter mode is commonly associated with memory hierarchies which support computation. VLSI devices can reasonably be defined as electronic circuit devices such as channel and control electronics as well as highly integrated, solid-state devices that are fabricated using thin film deposition technology. VLSI devices in both capacities play an important role in data storage technology. In addition to random access memories (RAM), read-only memories (ROM), and other silicon-based variations such as PROM's, EPROM's, and EEPROM's, integrated devices find their way into a variety of memory technologies which offer significant performance advantages. These memory technologies include magnetic tape, magnetic disk, magneto-optic disk, and vertical Bloch line memory. In this paper, some comparison between selected technologies will be made to demonstrate why more than one memory technology exists today, based for example on access time and storage density at the active bit and system levels.

  19. {sup 129}I interlaboratory comparison

    SciTech Connect

    Roberts, M.L.; Caffee, M.W.; Proctor, L.D.

    1996-05-01

    An interlaboratory comparison exercise for {sup 129}I has been organized and conducted. A total of seven laboratories participated in the exercise to either a full or limited extent. In the comparison, a suite of 11 samples were used. This suite of standards contained both synthetic `standard type` materials(i.e., AgI) and environmental materials. The isotopic {sup 129}I/{sup 127}I ratio of the samples varied from 10{sup -8} to 10{sup -14}. Preliminary results of the comparison are presented.

  20. Comparison of Artificial Compressibility Methods

    NASA Technical Reports Server (NTRS)

    Kiris, Cetin; Housman, Jeffrey; Kwak, Dochan

    2004-01-01

    Various artificial compressibility methods for calculating the three-dimensional incompressible Navier-Stokes equations are compared. Each method is described and numerical solutions to test problems are conducted. A comparison based on convergence behavior, accuracy, and robustness is given.

  1. On the Benefit of Dimensional Comparisons

    ERIC Educational Resources Information Center

    Pohlmann, Britta; Moller, Jens

    2009-01-01

    People not only use social comparisons to evaluate their abilities, they also engage in dimensional comparisons, comparing their own achievement in different domains. Processes of dimensional comparison have contrasting effects on subject-specific self-concepts: downward dimensional comparisons result in higher self-concept in the…

  2. Do ants make direct comparisons?

    PubMed

    Robinson, Elva J H; Smith, Faith D; Sullivan, Kathryn M E; Franks, Nigel R

    2009-07-22

    Many individual decisions are informed by direct comparison of the alternatives. In collective decisions, however, only certain group members may have the opportunity to compare options. Emigrating ant colonies (Temnothorax albipennis) show sophisticated nest-site choice, selecting superior sites even when they are nine times further away than the alternative. How do they do this? We used radio-frequency identification-tagged ants to monitor individual behaviour. Here we show for the first time that switching between nests during the decision process can influence nest choice without requiring direct comparison of nests. Ants finding the poor nest were likely to switch and find the good nest, whereas ants finding the good nest were more likely to stay committed to that nest. When ants switched quickly between the two nests, colonies chose the good nest. Switching by ants that had the opportunity to compare nests had little effect on nest choice. We suggest a new mechanism of collective nest choice: individuals respond to nest quality by the decision either to commit or to seek alternatives. Previously proposed mechanisms, recruitment latency and nest comparison, can be explained as side effects of this simple rule. Colony-level comparison and choice can emerge, without direct comparison by individuals.

  3. Do ants make direct comparisons?

    PubMed Central

    Robinson, Elva J.H.; Smith, Faith D.; Sullivan, Kathryn M.E.; Franks, Nigel R.

    2009-01-01

    Many individual decisions are informed by direct comparison of the alternatives. In collective decisions, however, only certain group members may have the opportunity to compare options. Emigrating ant colonies (Temnothorax albipennis) show sophisticated nest-site choice, selecting superior sites even when they are nine times further away than the alternative. How do they do this? We used radio-frequency identification-tagged ants to monitor individual behaviour. Here we show for the first time that switching between nests during the decision process can influence nest choice without requiring direct comparison of nests. Ants finding the poor nest were likely to switch and find the good nest, whereas ants finding the good nest were more likely to stay committed to that nest. When ants switched quickly between the two nests, colonies chose the good nest. Switching by ants that had the opportunity to compare nests had little effect on nest choice. We suggest a new mechanism of collective nest choice: individuals respond to nest quality by the decision either to commit or to seek alternatives. Previously proposed mechanisms, recruitment latency and nest comparison, can be explained as side effects of this simple rule. Colony-level comparison and choice can emerge, without direct comparison by individuals. PMID:19386652

  4. Protein Structure Comparison and Classification

    NASA Astrophysics Data System (ADS)

    Çamoǧlu, Orhan; Singh, Ambuj K.

    The success of genome projects has generated an enormous amount of sequence data. In order to realize the full value of the data, we need to understand its functional role and its evolutionary origin. Sequence comparison methods are incredibly valuable for this task. However, for sequences falling in the twilight zone (usually between 20 and 35% sequence similarity), we need to resort to structural alignment and comparison for a meaningful analysis. Such a structural approach can be used for classification of proteins, isolation of structural motifs, and discovery of drug targets.

  5. International Comparisons and Educational Reform.

    ERIC Educational Resources Information Center

    Purves, Alan C., Ed.

    Increasingly over the past decade there have appeared in the press bar graphs comparing the performance of U.S. students with their counterparts in other countries. Usually these graphs have been accompanied by dire warnings and pointing fingers. The main source of the data on international comparisons has been the International Association for…

  6. Inhibition in Dot Comparison Tasks

    ERIC Educational Resources Information Center

    Clayton, Sarah; Gilmore, Camilla

    2015-01-01

    Dot comparison tasks are commonly used to index an individual's Approximate Number System (ANS) acuity, but the cognitive processes involved in completing these tasks are poorly understood. Here, we investigated how factors including numerosity ratio, set size and visual cues influence task performance. Forty-four children aged 7-9 years completed…

  7. A comparison of five benchmarks

    NASA Technical Reports Server (NTRS)

    Huss, Janice E.; Pennline, James A.

    1987-01-01

    Five benchmark programs were obtained and run on the NASA Lewis CRAY X-MP/24. A comparison was made between the programs codes and between the methods for calculating performance figures. Several multitasking jobs were run to gain experience in how parallel performance is measured.

  8. Matrixed business support comparison study.

    SciTech Connect

    Parsons, Josh D.

    2004-11-01

    The Matrixed Business Support Comparison Study reviewed the current matrixed Chief Financial Officer (CFO) division staff models at Sandia National Laboratories. There were two primary drivers of this analysis: (1) the increasing number of financial staff matrixed to mission customers and (2) the desire to further understand the matrix process and the opportunities and challenges it creates.

  9. Metric-Free Distributional Comparisons.

    ERIC Educational Resources Information Center

    Haertel, Edward H.; And Others

    Two methods are presented for comparing distributions, such as achievement test score distributions, for distinctly different groups of persons in such a way that the comparison will not be influenced by the particular metric of the test being used. Both methods use percentile scores. One method, attributed to Flanagan, fits a straight line to the…

  10. Comparison of Air Temperature Calibrations

    NASA Astrophysics Data System (ADS)

    Heinonen, M.; Anagnostou, M.; Bartolo, J.; Bell, S.; Benyon, R.; Bergerud, R. A.; Bojkovski, J.; Böse, N.; Dinu, C.; Smorgon, D.; Flakiewicz, K.; Martin, M. J.; Nedialkov, S.; Nielsen, M. B.; Oğuz Aytekin, S.; Otych, J.; Pedersen, M.; Rujan, M.; Testa, N.; Turzó-András, E.; Vilbaste, M.; White, M.

    2014-07-01

    European national metrology institutes use calibration systems of various types for calibrating thermometers in air. These were compared to each other for the first time in a project organized by the European Association of National Metrology Institutes (EURAMET). This EURAMET P1061 comparison project had two main objectives: (1) to study the equivalence of calibrations performed by different laboratories and (2) to investigate correlations between calibration methods and achievable uncertainties. The comparison was realized using a pair of 100 platinum resistance thermometer probes connected to a digital thermometer bridge as the transfer standard. The probes had different dimensions and surface properties. The measurements covered the temperature range between and , but each laboratory chose a subrange most relevant to its scope and performed measurements at five nominal temperature points covering the subrange. To enable comparison between the laboratories, comparison reference functions were determined using weighted least-squares fitting. Various effects related to variations in heat transfer conditions were demonstrated but clear correlations to specific characteristics of calibration system were not identified. Calibrations in air and liquid agreed typically within at and . Expanded uncertainties determined by the participants ranged from to and they were shown to be realistic in most cases.

  11. Characteristics of Multiple Comparison Procedures.

    ERIC Educational Resources Information Center

    Yusuf, Mian Muhammad; And Others

    Multiple comparison procedures (MCPs), in the context of analysis of variance, are becoming more popular than the overall F tests. An attempt is made to clarify confusion among the different MCPs by systematically comparing and contrasting the procedures in terms of their purposes, restrictions, robustness to assumptions, and other special…

  12. The cosmic code comparison project

    NASA Astrophysics Data System (ADS)

    Heitmann, Katrin; Lukić, Zarija; Fasel, Patricia; Habib, Salman; Warren, Michael S.; White, Martin; Ahrens, James; Ankeny, Lee; Armstrong, Ryan; O'Shea, Brian; Ricker, Paul M.; Springel, Volker; Stadel, Joachim; Trac, Hy

    2008-10-01

    Current and upcoming cosmological observations allow us to probe structures on smaller and smaller scales, entering highly nonlinear regimes. In order to obtain theoretical predictions in these regimes, large cosmological simulations have to be carried out. The promised high accuracy from observations makes the simulation task very demanding: the simulations have to be at least as accurate as the observations. This requirement can only be fulfilled by carrying out an extensive code verification program. The first step of such a program is the comparison of different cosmology codes including gravitational interactions only. In this paper, we extend a recently carried out code comparison project to include five more simulation codes. We restrict our analysis to a small cosmological volume which allows us to investigate properties of halos. For the matter power spectrum and the mass function, the previous results hold, with the codes agreeing at the 10% level over wide dynamic ranges. We extend our analysis to the comparison of halo profiles and investigate the halo count as a function of local density. We introduce and discuss ParaView as a flexible analysis tool for cosmological simulations, the use of which immensely simplifies the code comparison task.

  13. Comparison of Optimal Thermodynamic Models of the Tricarboxylic Acid Cycle from Heterotrophs, Cyanobacteria, and Green Sulfur Bacteria

    SciTech Connect

    Thomas, Dennis G.; Jaramillo Riveri, Sebastian I.; Baxter, Douglas J.; Cannon, William R.

    2014-12-15

    We have applied a new stochastic simulation approach to predict the metabolite levels, energy flow, and material flux in the different oxidative TCA cycles found in E. coli and Synechococcus sp. PCC 7002, and in the reductive TCA cycle typical of chemolithoautotrophs and phototrophic green sulfur bacteria such as Chlorobaculum tepidum. The simulation approach is based on equations of state and employs an assumption similar to that used in transition state theory. The ability to evaluate the thermodynamics of metabolic pathways allows one to understand the relationship between coupling of energy and material gradients in the environment and the selforganization of stable biological systems, and it is shown that each cycle operates in the direction expected due to its environmental niche. The simulations predict changes in metabolite levels and flux in response to changes in cofactor concentrations that would be hard to predict without an elaborate model based on the law of mass action. In fact, we show that a thermodynamically unfavorable reaction can still have flux in the forward direction when it is part of a reaction network. The ability to predict metabolite levels, energy flow and material flux should be significant for understanding the dynamics of natural systems and for understanding principles for engineering organisms for production of specialty chemicals, such as biofuels.

  14. Group membership and everyday social comparison experiences

    PubMed Central

    SMITH, HEATHER J.; LEACH, COLIN W.

    2006-01-01

    In two everyday experience studies, we examined the degree to which everyday social comparisons are framed by group membership. In the first study, 30 undergraduates attending a public university in the United States completed short questionnaires about their social comparison experiences whenever they were signalled. In the second study, 34 ethnic minority undergraduates from the same university completed similar questionnaires about their social comparison experiences. Across both studies, comparisons in which participants viewed themselves as an ingroup member in comparison to an outgroup comprised less than 10% of the comparison experiences reported by participants. However, minorities in the second study who reported closer identification with their ethnic group reported more comparison experiences in which they mentioned their own or the comparison target's ethnicity. PMID:16691290

  15. High pressure rinsing system comparison

    SciTech Connect

    D. Sertore; M. Fusetti; P. Michelato; Carlo Pagani; Toshiyasu Higo; Jin-Seok Hong; K. Saito; G. Ciovati; T. Rothgeb

    2007-06-01

    High pressure rinsing (HPR) is a key process for the surface preparation of high field superconducting cavities. A portable apparatus for the water jet characterization, based on the transferred momentum between the water jet and a load cell, has been used in different laboratories. This apparatus allows to collected quantitative parameters that characterize the HPR water jet. In this paper, we present a quantitative comparison of the different water jet produced by various nozzles routinely used in different laboratories for the HPR process

  16. Comparison of Artificial Compressibility Methods

    NASA Technical Reports Server (NTRS)

    Kiris, Cetin; Housman, Jeffrey; Kwak, Dochan

    2003-01-01

    Various artificial compressibility methods for calculating three-dimensional, steady and unsteady, laminar and turbulent, incompressible Navier-Stokes equations are compared in this work. Each method is described in detail along with appropriate physical and numerical boundary conditions. Analysis of well-posedness and numerical solutions to test problems for each method are provided. A comparison based on convergence behavior, accuracy, stability and robustness is used to establish the relative positive and negative characteristics of each method.

  17. Nonphotochemical Hole-Burning Studies of Energy Transfer Dynamics in Antenna Complexes of Photosynthetic Bacteria

    SciTech Connect

    Satoshi Matsuzaki

    2002-06-27

    This thesis contains the candidate's original work on excitonic structure and energy transfer dynamics of two bacterial antenna complexes as studied using spectral hole-burning spectroscopy. The general introduction is divided into two chapters (1 and 2). Chapter 1 provides background material on photosynthesis and bacterial antenna complexes with emphasis on the two bacterial antenna systems related to the thesis research. Chapter 2 reviews the underlying principles and mechanism of persistent nonphotochemical hole-burning (NPHB) spectroscopy. Relevant energy transfer theories are also discussed. Chapters 3 and 4 are papers by the candidate that have been published. Chapter 3 describes the application of NPHB spectroscopy to the Fenna-Matthews-Olson (FMO) complex from the green sulfur bacterium Prosthecochloris aestuarii; emphasis is on determination of the low energy vibrational structure that is important for understanding the energy transfer process associated within three lowest energy Q{sub y}-states of the complex. The results are compared with those obtained earlier on the FMO complex from Chlorobium tepidum. In Chapter 4, the energy transfer dynamics of the B800 molecules of intact LH2 and B800-deficient LH2 complexes of the purple bacterium Rhodopseudomonas acidophila are compared. New insights on the additional decay channel of the B800 ring of bacteriochlorophyll{sub a} (BChl{sub a}) molecules are provided. General conclusions are given in Chapter 5. A version of the hole spectrum simulation program written by the candidate for the FMO complex study (Chapter 3) is included as an appendix. The references for each chapter are given at the end of each chapter.

  18. How collective comparisons emerge without individual comparisons of the options.

    PubMed

    Robinson, Elva J H; Feinerman, Ofer; Franks, Nigel R

    2014-07-22

    Collective decisions in animal groups emerge from the actions of individuals who are unlikely to have global information. Comparative assessment of options can be valuable in decision-making. Ant colonies are excellent collective decision-makers, for example when selecting a new nest-site. Here, we test the dependency of this cooperative process on comparisons conducted by individual ants. We presented ant colonies with a choice between new nests: one good and one poor. Using individually radio-tagged ants and an automated system of doors, we manipulated individual-level access to information: ants visiting the good nest were barred from visiting the poor one and vice versa. Thus, no ant could individually compare the available options. Despite this, colonies still emigrated quickly and accurately when comparisons were prevented. Individual-level rules facilitated this behavioural robustness: ants allowed to experience only the poor nest subsequently searched more. Intriguingly, some ants appeared particularly discriminating across emigrations under both treatments, suggesting they had stable, high nest acceptance thresholds. Overall, our results show how a colony of ants, as a cognitive entity, can compare two options that are not both accessible by any individual ant. Our findings illustrate a collective decision process that is robust to differences in individual access to information.

  19. Comparison of automatic control systems

    NASA Technical Reports Server (NTRS)

    Oppelt, W

    1941-01-01

    This report deals with a reciprocal comparison of an automatic pressure control, an automatic rpm control, an automatic temperature control, and an automatic directional control. It shows the difference between the "faultproof" regulator and the actual regulator which is subject to faults, and develops this difference as far as possible in a parallel manner with regard to the control systems under consideration. Such as analysis affords, particularly in its extension to the faults of the actual regulator, a deep insight into the mechanism of the regulator process.

  20. Comparison of ASGARD and UFOCapture

    NASA Astrophysics Data System (ADS)

    Blaauw, R.; Cruse, K. S.

    2012-01-01

    The Meteoroid Environment Office is undertaking a comparison between UFOCapture/Analyzer and Asgard (All Sky and Guided Automatic Realtime Detection), both software used to detect meteors. To accomplish this, video output from a Watec video camera on a 17 mm Schneider lens (25degrees field of view) was split and input into two computers, one running UFOCapture and the other running Asgard. The purpose of this study is to compare the sensitivity of the two systems, false alarm rates, and ease of use.

  1. Comparison of ASGARD and UFOCapture

    NASA Technical Reports Server (NTRS)

    Blaauw, Rhiannon C.; Cruse, Katherine S.

    2011-01-01

    The Meteoroid Environment Office is undertaking a comparison between UFOCapture/Analyzer and ASGARD (All Sky and Guided Automatic Realtime Detection). To accomplish this, video output from a Watec video camera on a 17 mm Schneider lens (25 degree field of view) was split and input into the two different meteor detection softwares. The purpose of this study is to compare the sensitivity of the two systems, false alarm rates and trajectory information, among other quantities. The important components of each software will be highlighted and comments made about the detection/rejection algorithms and the amount of user-labor required for each system.

  2. Selected Theoretical Comparisons for Bosons

    NASA Astrophysics Data System (ADS)

    Proukakis, Nick P.; Davis, Matthew J.; Gardiner, Simon A.

    2013-02-01

    One of the aims of the organisers of the FINESS conferences, and of the editors of this book, has been to encourage dialogue between researchers working in the general area of non-equilibrium superfluids. The researchers come from widely different backgrounds, and come with a broad array of favourite theoretical techniques. In this chapter we present an incomplete survey of figures from previously published papers that make a comparison between selected subsets of different theoretical methods. The goal is that this compilation of figures, when placed in a broader context, will provide some background for the reader to understand the physical conditions that determine when various theories are useful.

  3. RISKIND verification and benchmark comparisons

    SciTech Connect

    Biwer, B.M.; Arnish, J.J.; Chen, S.Y.; Kamboj, S.

    1997-08-01

    This report presents verification calculations and benchmark comparisons for RISKIND, a computer code designed to estimate potential radiological consequences and health risks to individuals and the population from exposures associated with the transportation of spent nuclear fuel and other radioactive materials. Spreadsheet calculations were performed to verify the proper operation of the major options and calculational steps in RISKIND. The program is unique in that it combines a variety of well-established models into a comprehensive treatment for assessing risks from the transportation of radioactive materials. Benchmark comparisons with other validated codes that incorporate similar models were also performed. For instance, the external gamma and neutron dose rate curves for a shipping package estimated by RISKIND were compared with those estimated by using the RADTRAN 4 code and NUREG-0170 methodology. Atmospheric dispersion of released material and dose estimates from the GENII and CAP88-PC codes. Verification results have shown the program to be performing its intended function correctly. The benchmark results indicate that the predictions made by RISKIND are within acceptable limits when compared with predictions from similar existing models.

  4. Comparisons of gyrofluid and gyrokinetic simulations

    SciTech Connect

    Parker, S.E.; Dorland, W.; Santoro, R.A.; Beer, M.A.; Liu, Q.P.; Lee, W.W.; Hammett, G.W.

    1994-03-01

    The gyrokinetic and gyrofluid models show the most promise for large scale simulations of tokamak microturbulence. This paper discusses detailed comparisons of these two complementary approaches. Past comparisons with linear theory have been fairly good, therefore the emphasis here is on nonlinear comparisons. Simulations include simple two dimensional slab test cases, turbulent three dimensional slab cases, and toroidal cases, each modeling the nonlinear evolution of the ion temperature gradient instability. There is good agreement in both turbulent and coherent nonlinear slab comparisons in terms of the ion heat flux, both in magnitude and scaling with magnetic shear. However, the nonlinear saturation level for {vert_bar}{Phi}{vert_bar} in the slab comparisons show differences of approximately 40%. Preliminary toroidal comparisons show agreement within 50%, in terms of ion heat flux and saturation level.

  5. Computational Chemistry Comparison and Benchmark Database

    National Institute of Standards and Technology Data Gateway

    SRD 101 NIST Computational Chemistry Comparison and Benchmark Database (Web, free access)   The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of molecules. The goals are to provide a benchmark set of molecules for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of thermochemical properties.

  6. European Measurement Comparisons of Environmental Radioactivity

    NASA Astrophysics Data System (ADS)

    Wätjen, Uwe

    2008-08-01

    The scheme of European measurement comparisons to verify radioactivity monitoring in the European Union is briefly explained. After a review of comparisons conducted during the years 1990, the approach of IRMM organising these comparisons since 2003 is presented. IRMM is providing comparison samples with a reference value traceable to the SI units and which is fully documented to all participants and national authorities after completion of the comparison. The sample preparation and determination of traceable reference values at IRMM, the sample treatment and measurement in the participating laboratories, as well as the evaluation of comparison results are described in some detail using the example of an air filter comparison. The results of a comparison to determine metabolised 40K, 90Sr and 137Cs in milk powder are presented as well. The necessary improvements in the estimation of measurement uncertainty by the participating laboratories are discussed. The performance of individual laboratories which have participated in at least four comparison exercises over the years is studied in terms of observable trends.

  7. The neural correlates of beauty comparison.

    PubMed

    Kedia, Gayannée; Mussweiler, Thomas; Mullins, Paul; Linden, David E J

    2014-05-01

    Beauty is in the eye of the beholder. How attractive someone is perceived to be depends on the individual or cultural standards to which this person is compared. But although comparisons play a central role in the way people judge the appearance of others, the brain processes underlying attractiveness comparisons remain unknown. In the present experiment, we tested the hypothesis that attractiveness comparisons rely on the same cognitive and neural mechanisms as comparisons of simple nonsocial magnitudes such as size. We recorded brain activity with functional magnetic resonance imaging (fMRI) while participants compared the beauty or height of two women or two dogs. Our data support the hypothesis of a common process underlying these different types of comparisons. First, we demonstrate that the distance effect characteristic of nonsocial comparisons also holds for attractiveness comparisons. Behavioral results indicated, for all our comparisons, longer response times for near than far distances. Second, the neural correlates of these distance effects overlapped in a frontoparietal network known for its involvement in processing simple nonsocial quantities. These results provide evidence for overlapping processes in the comparison of physical attractiveness and nonsocial magnitudes.

  8. European Measurement Comparisons of Environmental Radioactivity

    SciTech Connect

    Waetjen, Uwe

    2008-08-14

    The scheme of European measurement comparisons to verify radioactivity monitoring in the European Union is briefly explained. After a review of comparisons conducted during the years 1990, the approach of IRMM organising these comparisons since 2003 is presented. IRMM is providing comparison samples with a reference value traceable to the SI units and which is fully documented to all participants and national authorities after completion of the comparison. The sample preparation and determination of traceable reference values at IRMM, the sample treatment and measurement in the participating laboratories, as well as the evaluation of comparison results are described in some detail using the example of an air filter comparison. The results of a comparison to determine metabolised {sup 40}K, {sup 90}Sr and {sup 137}Cs in milk powder are presented as well. The necessary improvements in the estimation of measurement uncertainty by the participating laboratories are discussed. The performance of individual laboratories which have participated in at least four comparison exercises over the years is studied in terms of observable trends.

  9. The neural correlates of beauty comparison.

    PubMed

    Kedia, Gayannée; Mussweiler, Thomas; Mullins, Paul; Linden, David E J

    2014-05-01

    Beauty is in the eye of the beholder. How attractive someone is perceived to be depends on the individual or cultural standards to which this person is compared. But although comparisons play a central role in the way people judge the appearance of others, the brain processes underlying attractiveness comparisons remain unknown. In the present experiment, we tested the hypothesis that attractiveness comparisons rely on the same cognitive and neural mechanisms as comparisons of simple nonsocial magnitudes such as size. We recorded brain activity with functional magnetic resonance imaging (fMRI) while participants compared the beauty or height of two women or two dogs. Our data support the hypothesis of a common process underlying these different types of comparisons. First, we demonstrate that the distance effect characteristic of nonsocial comparisons also holds for attractiveness comparisons. Behavioral results indicated, for all our comparisons, longer response times for near than far distances. Second, the neural correlates of these distance effects overlapped in a frontoparietal network known for its involvement in processing simple nonsocial quantities. These results provide evidence for overlapping processes in the comparison of physical attractiveness and nonsocial magnitudes. PMID:23508477

  10. Visual Color Comparisons in Forensic Science.

    PubMed

    Thornton, J I

    1997-06-01

    Color is used extensively in forensic science for the characterization and comparison of physical evidence, and should thus be well understood. Fundamental elements of color perception and color comparison systems are first reviewed. The second portion of this article discusses instances in which defects in color perception may occur, and the recognition of opportunities by means of which color perception and color discrimination may be expressed and enhanced. Application and limitations of color comparisons in forensic science, including soil, paint, and fibers comparisons and color tests, are reviewed.

  11. Comparison of Holdup Measurement Techniques

    SciTech Connect

    Lousteau, Angela L; Stooksbury, John C; Cleveland, Steven L

    2012-01-01

    The measurement of uranium holdup, the residual material left in process equipment such as pipes or ducts, is an integral element of material control and accountability. Not only are the measurements important for accountability, they are also important for criticality safety. The goal in measuring holdup is to quantify the amount of material in the pipes to verify that all material is accounted for (inventory in [inventory out + holdup] = 0) and to ensure that the amount of material heldup is not a criticality risk. There are a number of ways to measure holdup in process equipment; however, this paper will evaluate only two methods (i.e., Holdup Measurement System 4 (HMS-4) and In Situ Object Counting Software (ISOCS)) for specific measurement scenarios. The comparison will use measurements of well-known reference materials in various configurations and will examine the results, uncertainties, repeatability, time required, portability, and cost of each system.

  12. Comparison of energy calculation procedures

    SciTech Connect

    Kusuda, T.

    1981-08-01

    ASHRAE has developed a simplified energy-calculation procedure suitable for small calculators that applied to nonresidential buildings and includes all the essential calculation elements - climatic data, buildings construction, operational characteristics, utility system and equipment performance, and internal heat gain due to lighting, occupancy, cooking, etc. A comparison of the results predicted by the proposed method for four typical HVAC (heating, ventilation, and air conditioning) systems in an office building in Washington, DC, against the predictions of seven detailed computer-simulation programs - AXCESS, BLAST, BLDSIM, DOE-2, E-CUBE, ESAS, and TRACE - revealed that the similarity of the results depended more on which analyst employed the methods than on which methods were used.

  13. MCNPX Model/Table Comparison

    SciTech Connect

    J.S. Hendricks

    2003-03-03

    MCNPX is a Monte Carlo N-Particle radiation transport code extending the capabilities of MCNP4C. As with MCNP, MCNPX uses nuclear data tables to transport neutrons, photons, and electrons. Unlike MCNP, MCNPX also uses (1) nuclear data tables to transport protons; (2) physics models to transport 30 additional particle types (deuterons, tritons, alphas, pions, muons, etc.); and (3) physics models to transport neutrons and protons when no tabular data are available or when the data are above the energy range (20 to 150 MeV) where the data tables end. MCNPX can mix and match data tables and physics models throughout a problem. For example, MCNPX can model neutron transport in a bismuth germinate (BGO) particle detector by using data tables for bismuth and oxygen and using physics models for germanium. Also, MCNPX can model neutron transport in UO{sub 2}, making the best use of physics models and data tables: below 20 MeV, data tables are used; above 150 MeV, physics models are used; between 20 and 150 MeV, data tables are used for oxygen and models are used for uranium. The mix-and-match capability became available with MCNPX2.5.b (November 2002). For the first time, we present here comparisons that calculate radiation transport in materials with various combinations of data charts and model physics. The physics models are poor at low energies (<150 MeV); thus, data tables should be used when available. Our comparisons demonstrate the importance of the mix-and-match capability and indicate how well physics models work in the absence of data tables.

  14. Commentary: Problematic issues in cultural comparisons.

    PubMed

    Campesino, Maureen

    2002-01-01

    This commentary offers a critique of cross-cultural comparisons of health care systems between the United States and less economically developed nations. Two main issues are discussed: the abuse of power in such comparisons and the reluctance of nurses from the United States to address conditions of suffering in their own country. Recommendations are given to increase sensitivity of nurses. PMID:12486641

  15. Adaptive sequential testing for multiple comparisons.

    PubMed

    Gao, Ping; Liu, Lingyun; Mehta, Cyrus

    2014-01-01

    We propose a Markov process theory-based adaptive sequential testing procedure for multiple comparisons. The procedure can be used for confirmative trials involving multi-comparisons, including dose selection or population enrichment. Dose or subpopulation selection and sample size modification can be made at any interim analysis. Type I error control is exact. PMID:24926848

  16. Comparison of debris flux models

    NASA Astrophysics Data System (ADS)

    Sdunnus, H.; Beltrami, P.; Klinkrad, H.; Matney, M.; Nazarenko, A.; Wegener, P.

    The availability of models to estimate the impact risk from the man-made space debris and the natural meteoroid environment is essential for both, manned and unmanned satellite missions. Various independent tools based on different approaches have been developed in the past years. Due to an increased knowledge of the debris environment and its sources e.g. from improved measurement capabilities, these models could be updated regularly, providing more detailed and more reliable simulations. This paper addresses an in-depth, quantitative comparison of widely distributed debris flux models which were recently updated, namely ESA's MASTER 2001 model, NASA's ORDEM 2000 and the Russian SDPA 2000 model. The comparison was performed in the frame of the work of the 20t h Interagency Debris Coordination (IADC) meeting held in Surrey, UK. ORDEM 2000ORDEM 2000 uses careful empirical estimates of the orbit populations based onthree primary data sources - the US Space Command Catalog, the H ystackaRadar, and the Long Duration Exposure Facility spacecraft returned surfaces.Further data (e.g. HAX and Goldstone radars, impacts on Shuttle windows andradiators, and others) were used to adjust these populations for regions in time,size, and space not covered by the primary data sets. Some interpolation andextrapolation to regions with no data (such as projections into the future) wasprovided by the EVOLVE model. MASTER 2001The ESA MASTER model offers a full three dimensional description of theterrestrial debris distribution reaching from LEO up to the GEO region. Fluxresults relative to an orbiting target or to an inertial volume can be resolved intosource terms, impactor characteristics and orbit, as well as impact velocity anddirection. All relevant debris source terms are considered by the MASTERmodel. For each simulated source, a corresponding debris generation model interms of mass/diameter distribution, additional velocities, and directionalspreading has been developed. A

  17. What Is Social Comparison and How Should We Study It?

    ERIC Educational Resources Information Center

    Wood, Joanne V.

    1996-01-01

    Examines frequently used measures and procedures in social comparison research. The question of whether a method truly captures social comparison requires a clear understanding of what social comparison is; hence a definition of social comparison is proposed, multiple ancillary processes in social comparison are identified, and definitional…

  18. Risk comparisons, conflict, and risk acceptability claims.

    PubMed

    Johnson, Branden B

    2004-02-01

    Despite many claims for and against the use of risk comparisons in risk communication, few empirical studies have explored their effect. Even fewer have examined the public's relative preferences among different kinds of risk comparisons. Two studies, published in this journal in 1990 and 2003, used seven measures of "acceptability" to examine public reaction to 14 examples of risk comparisons, as used by a hypothetical factory manager to explain risks of his ethylene oxide plant. This study examined the effect on preferences of scenarios involving low or high conflict between the factory manager and residents of the hypothetical town (as had the 2003 study), and inclusion of a claim that the comparison demonstrated the risks' acceptability. It also tested the Finucane et al. (2000) affect hypothesis that information emphasizing low risks-as in these risk comparisons-would raise benefits estimates without changing risk estimates. Using similar but revised scenarios, risk comparison examples (10 instead of 14), and evaluation measures, an opportunity sample of 303 New Jersey residents rated the comparisons, and the risks and benefits of the factory. On average, all comparisons received positive ratings on all evaluation measures in all conditions. Direct and indirect measures showed that the conflict manipulation worked; overall, No-Conflict and Conflict scenarios evoked scores that were not significantly different. The attachment to each risk comparison of a risk acceptability claim ("So our factory's risks should be acceptable to you.") did not worsen ratings relative to conditions lacking this claim. Readers who did or did not see this claim were equally likely to infer an attempt to persuade them to accept the risk from the comparison. As in the 2003 article, there was great individual variability in inferred rankings of the risk comparisons. However, exposure to the risk comparisons did not reduce risk estimates significantly (while raising benefit estimates

  19. RTU Comparison Calculator Enhancement Plan

    SciTech Connect

    Miller, James D.; Wang, Weimin; Katipamula, Srinivas

    2015-07-01

    Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.

  20. Comparison of microarray preprocessing methods.

    PubMed

    Shakya, K; Ruskin, H J; Kerr, G; Crane, M; Becker, J

    2010-01-01

    Data preprocessing in microarray technology is a crucial initial step before data analysis is performed. Many preprocessing methods have been proposed but none has proved to be ideal to date. Frequently, datasets are limited by laboratory constraints so that the need is for guidelines on quality and robustness, to inform further experimentation while data are yet restricted. In this paper, we compared the performance of four popular methods, namely MAS5, Li & Wong pmonly (LWPM), Li & Wong subtractMM (LWMM), and Robust Multichip Average (RMA). The comparison is based on the analysis carried out on sets of laboratory-generated data from the Bioinformatics Lab, National Institute of Cellular Biotechnology (NICB), Dublin City University, Ireland. These experiments were designed to examine the effect of Bromodeoxyuridine (5-bromo-2-deoxyuridine, BrdU) treatment in deep lamellar keratoplasty (DLKP) cells. The methodology employed is to assess dispersion across the replicates and analyze the false discovery rate. From the dispersion analysis, we found that variability is reduced more effectively by LWPM and RMA methods. From the false positive analysis, and for both parametric and nonparametric approaches, LWMM is found to perform best. Based on a complementary q-value analysis, LWMM approach again is the strongest candidate. The indications are that, while LWMM is marginally less effective than LWPM and RMA in terms of variance reduction, it has considerably improved discrimination overall.

  1. RTU Comparison Calculator Enhancement Plan

    SciTech Connect

    Miller, James D.; Wang, Weimin; Katipamula, Srinivas

    2014-03-31

    Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.

  2. Distributed Wind Policy Comparison Tool

    SciTech Connect

    2011-12-01

    Power through Policy: 'Best Practices' for Cost-Effective Distributed Wind is a U.S. Department of Energy (DOE)-funded project to identify distributed wind technology policy best practices and to help policymakers, utilities, advocates, and consumers examine their effectiveness using a pro forma model. Incorporating a customized feed from the Database of State Incentives for Renewables and Efficiency (DSIRE), the Web-based Distributed Wind Policy Comparison Tool (Policy Tool) is designed to assist state, local, and utility officials in understanding the financial impacts of different policy options to help reduce the cost of distributed wind technologies. The Policy Tool can be used to evaluate the ways that a variety of federal and state policies and incentives impact the economics of distributed wind (and subsequently its expected market growth). It also allows policymakers to determine the impact of policy options, addressing market challenges identified in the U.S. DOE’s '20% Wind Energy by 2030' report and helping to meet COE targets.

  3. Attractor comparisons based on density

    SciTech Connect

    Carroll, T. L.

    2015-01-15

    Recognizing a chaotic attractor can be seen as a problem in pattern recognition. Some feature vector must be extracted from the attractor and used to compare to other attractors. The field of machine learning has many methods for extracting feature vectors, including clustering methods, decision trees, support vector machines, and many others. In this work, feature vectors are created by representing the attractor as a density in phase space and creating polynomials based on this density. Density is useful in itself because it is a one dimensional function of phase space position, but representing an attractor as a density is also a way to reduce the size of a large data set before analyzing it with graph theory methods, which can be computationally intensive. The density computation in this paper is also fast to execute. In this paper, as a demonstration of the usefulness of density, the density is used directly to construct phase space polynomials for comparing attractors. Comparisons between attractors could be useful for tracking changes in an experiment when the underlying equations are too complicated for vector field modeling.

  4. Performance Comparison of CGM Systems

    PubMed Central

    Kirchsteiger, Harald; Heinemann, Lutz; Freckmann, Guido; Lodwig, Volker; Schmelzeisen-Redeker, Günther; Schoemaker, Michael; del Re, Luigi

    2015-01-01

    Background: The ongoing progress of continuous glucose monitoring (CGM) systems results in an increasing interest in comparing their performance, in particular in terms of accuracy, that is, matching CGM readings with reference values measured at the same time. Most often accuracy is evaluated by the mean absolute relative difference (MARD). It is frequently overseen that MARD does not only reflect accuracy, but also the study protocol and evaluation procedure, making a cross-study comparison problematic. Methods: We evaluate the effect of several factors on the MARD statistical properties: number of paired reference and CGM values, distribution of the paired values, accuracy of the reference measurement device itself and the time delay between data pairs. All analysis is done using clinical data from 12 patients wearing 6 sensors each. Results: We have found that a few paired points can have a potentially high impact on MARD. Leaving out those points for evaluation thus reduces the MARD. Similarly, accuracy of the reference measurements greatly affects the MARD as numerical and graphical data show. Results also show that a log-normal distribution of the paired references provides a significantly different MARD than, for example, a uniform distribution. Conclusions: MARD is a reasonable parameter to characterize the performance of CGM systems when keeping its limitations in mind. To support clinicians and patients in selecting which CGM system to use in a clinical setting, care should be taken to make MARD more comparable by employing a standardized evaluation procedure. PMID:26330485

  5. CCN Cloud Processing Interhemispheric Comparisons

    NASA Astrophysics Data System (ADS)

    Tabor, S. S.; Noble, S. R., Jr.; Hudson, J. G.

    2014-12-01

    Cloud processing of CCN spectra is described by Hudson and Noble (2014) and Noble and Hudson (2014). Bimodal CCN spectra have also been observed in 4 Southern Hemisphere (SH) cloud research projects: SOCEX1, July 1993 and 2, Jan-Feb, 1995 and ACE1, Nov-Dec, 1995 all off Tasmania and INDOEX, Feb-Mar, 1999 Indian Ocean (Fig.). However, as in the Northern Hemisphere (NH) bimodal CCN spectra are interspersed with monomodal spectra, which indicates that cloudy boundary layers are not as well-mixed as conventional wisdom. Hoppel minima between the modes provide estimates of cloud effective supersaturations (Seff). Unlike DMA measurements particle composition/hygroscopicity (κ) is not needed for these Seff estimate because CCN are measured in terms of S. However, these Hoppel Seff often tend to be lower than Seff obtained by comparing below cloud CCN spectra with nearby cloud droplet concentrations (Nc). These Seff differences may be due to less cloud processing by smaller cloud droplets. However, this may be a smaller issue in the SH due to larger droplets in cleaner air masses. Furthermore, SH Seff may also tend to be higher for the same reason. This might reduce the Seff differences of the two types of estimates compared to the more polluted NH. SH/NH comparisons of detailed differential CCN spectra can provide an important baseline for preindustrial aerosol. Relative differences between the contribution of chemical and physical cloud processing between hemispheres also provide important baseline characteristics. Chemical processing enhance the indirect aerosol effect (IAE) by moving CCN to lower critical S (Sc), which increases droplet concentrations (Nc) whereas physical processing reduces IAE by inherently reducing CCN (Noble and Hudson 2014). The extent of cloud processing is as important as CCN sources. Hudson and Noble 2014, this meeting. Noble and Hudson 2014, this meeting.

  6. Uav Photogrammetry: Block Triangulation Comparisons

    NASA Astrophysics Data System (ADS)

    Gini, R.; Pagliari, D.; Passoni, D.; Pinto, L.; Sona, G.; Dosso, P.

    2013-08-01

    UAVs systems represent a flexible technology able to collect a big amount of high resolution information, both for metric and interpretation uses. In the frame of experimental tests carried out at Dept. ICA of Politecnico di Milano to validate vector-sensor systems and to assess metric accuracies of images acquired by UAVs, a block of photos taken by a fixed wing system is triangulated with several software. The test field is a rural area included in an Italian Park ("Parco Adda Nord"), useful to study flight and imagery performances on buildings, roads, cultivated and uncultivated vegetation. The UAV SenseFly, equipped with a camera Canon Ixus 220HS, flew autonomously over the area at a height of 130 m yielding a block of 49 images divided in 5 strips. Sixteen pre-signalized Ground Control Points, surveyed in the area through GPS (NRTK survey), allowed the referencing of the block and accuracy analyses. Approximate values for exterior orientation parameters (positions and attitudes) were recorded by the flight control system. The block was processed with several software: Erdas-LPS, EyeDEA (Univ. of Parma), Agisoft Photoscan, Pix4UAV, in assisted or automatic way. Results comparisons are given in terms of differences among digital surface models, differences in orientation parameters and accuracies, when available. Moreover, image and ground point coordinates obtained by the various software were independently used as initial values in a comparative adjustment made by scientific in-house software, which can apply constraints to evaluate the effectiveness of different methods of point extraction and accuracies on ground check points.

  7. OpenMP Experiences and Comparisons

    NASA Technical Reports Server (NTRS)

    Nelson, Terry; Thigpen, William W. (Technical Monitor)

    2002-01-01

    The document discusses message passage interfaces (MPI), open message passage issues and parallelization. A comparison of the two vector platforms, C90 and SVlex is presented. Sections of the document are written in computer code.

  8. STS-134 Launch Composite Video Comparison

    NASA Video Gallery

    A side-by-side comparison video shows a one-camera view of the STS-134 launch (left) with the six-camera composited view (right). Imaging experts funded by the Space Shuttle Program and located at ...

  9. Comparison of LASSO and GPS time transfers

    NASA Technical Reports Server (NTRS)

    Lewandowski, W.; Petit, G.; Baumont, F.; Fridelance, P.; Gaignebet, J.; Grudler, P.; Veillet, C.; Wiant, J.; Klepczynski, W. J.

    1994-01-01

    The LASSO is a technique which should allow the comparison of remote atomic clocks with sub-nanosecond precision and accuracy. The first successful time transfer using LASSO has been carried out between the Observatoire de la Cote d'Azur in France and the McDonald Observatory in Texas, United States. This paper presents a preliminary comparison of LASSO time transfer with GPS common-view time transfer.

  10. Rankings, Standards, and Competition: Task vs. Scale Comparisons

    ERIC Educational Resources Information Center

    Garcia, Stephen M.; Tor, Avishalom

    2007-01-01

    Research showing how upward social comparison breeds competitive behavior has so far conflated local comparisons in "task" performance (e.g. a test score) with comparisons on a more general "scale" (i.e. an underlying skill). Using a ranking methodology (Garcia, Tor, & Gonzalez, 2006) to separate task and scale comparisons, Studies 1-2 reveal that…

  11. Differential Item Functioning Detection across Two Methods of Defining Group Comparisons: Pairwise and Composite Group Comparisons

    ERIC Educational Resources Information Center

    Sari, Halil Ibrahim; Huggins, Anne Corinne

    2015-01-01

    This study compares two methods of defining groups for the detection of differential item functioning (DIF): (a) pairwise comparisons and (b) composite group comparisons. We aim to emphasize and empirically support the notion that the choice of pairwise versus composite group definitions in DIF is a reflection of how one defines fairness in DIF…

  12. Comparison of Tritium Component Failure Rate Data

    SciTech Connect

    Lee C. Cadwallader

    2004-09-01

    Published failure rate values from the US Tritium Systems Test Assembly, the Japanese Tritium Process Laboratory, the German Tritium Laboratory Karlsruhe, and the Joint European Torus Active Gas Handling System have been compared. This comparison is on a limited set of components, but there is a good variety of data sets in the comparison. The data compared reasonably well. The most reasonable failure rate values are recommended for use on next generation tritium handling system components, such as those in the tritium plant systems for the International Thermonuclear Experimental Reactor and the tritium fuel systems of inertial fusion facilities, such as the US National Ignition Facility. These data and the comparison results are also shared with the International Energy Agency cooperative task on fusion component failure rate data.

  13. Photon/Electron Benchmarks for Intercode Comparisons

    SciTech Connect

    Hughes, Henry Grady III; Sweezy, Jeremy Ed; Lemaire, Sebastien

    2015-07-21

    The goal of this work was to improve accuracy and efficiency of two Monte-Carlo transport codes (MCNP and DIANE) with an emphasis on γ+electron physics. The approach involved intercode comparisons + measurements for gamma/e- energy deposition in a cylinder with a photon source and different materials (C, Pb) and the bombardment of 15-MeV electrons on thick targets (Al, Be, Pb). Comparisons of the codes DIANE and MCNP6 showed good agreement (differences < 3%) for gamma-electron energy deposition in a 2D cylinder, except for the first 0.1 μm of lead (difference < 10%). Comparisons with measurements showed generally good agreement, often better than 10%; best-performing codes/options are problem-dependent; and single-event discrepancies are in active use in reviewing electron elastic scattering.

  14. Real medical benefit assessed by indirect comparison.

    PubMed

    Falissard, Bruno; Zylberman, Myriam; Cucherat, Michel; Izard, Valérie; Meyer, François

    2009-01-01

    Frequently, in data packages submitted for Marketing Approval to the CHMP, there is a lack of relevant head-to-head comparisons of medicinal products that could enable national authorities responsible for the approval of reimbursement to assess the Added Therapeutic Value (ASMR) of new clinical entities or line extensions of existing therapies.Indirect or mixed treatment comparisons (MTC) are methods stemming from the field of meta-analysis that have been designed to tackle this problem. Adjusted indirect comparisons, meta-regressions, mixed models, Bayesian network analyses pool results of randomised controlled trials (RCTs), enabling a quantitative synthesis.The REAL procedure, recently developed by the HAS (French National Authority for Health), is a mixture of an MTC and effect model based on expert opinions. It is intended to translate the efficacy observed in the trials into effectiveness expected in day-to-day clinical practice in France. PMID:19671436

  15. Real medical benefit assessed by indirect comparison.

    PubMed

    Falissard, Bruno; Zylberman, Myriam; Cucherat, Michel; Izard, Valérie; Meyer, François

    2009-01-01

    Frequently, in data packages submitted for Marketing Approval to the CHMP, there is a lack of relevant head-to-head comparisons of medicinal products that could enable national authorities responsible for the approval of reimbursement to assess the Added Therapeutic Value (ASMR) of new clinical entities or line extensions of existing therapies.Indirect or mixed treatment comparisons (MTC) are methods stemming from the field of meta-analysis that have been designed to tackle this problem. Adjusted indirect comparisons, meta-regressions, mixed models, Bayesian network analyses pool results of randomised controlled trials (RCTs), enabling a quantitative synthesis.The REAL procedure, recently developed by the HAS (French National Authority for Health), is a mixture of an MTC and effect model based on expert opinions. It is intended to translate the efficacy observed in the trials into effectiveness expected in day-to-day clinical practice in France.

  16. Infrared spectral normal emittance/emissivity comparison

    NASA Astrophysics Data System (ADS)

    Hanssen, L.; Wilthan, B.; Filtz, J.-R.; Hameury, J.; Girard, F.; Battuello, M.; Ishii, J.; Hollandt, J.; Monte, C.

    2016-01-01

    The National Measurement Institutes (NMIs) of the United States, Germany, France, Italy and Japan, have joined in an inter-laboratory comparison of their infrared spectral emittance scales. This action is part of a series of supplementary inter-laboratory comparisons (including thermal conductivity and thermal diffusivity) sponsored by the Consultative Committee on Thermometry (CCT) Task Group on Thermophysical Quantities (TG-ThQ). The objective of this collaborative work is to strengthen the major operative National Measurement Institutes' infrared spectral emittance scales and consequently the consistency of radiative properties measurements carried out worldwide. The comparison has been performed over a spectral range of 2 μm to 14 μm, and a temperature range from 23 °C to 800 °C. Artefacts included in the comparison are potential standards: oxidized Inconel, boron nitride, and silicon carbide. The measurement instrumentation and techniques used for emittance scales are unique for each NMI, including the temperature ranges covered as well as the artefact sizes required. For example, all three common types of spectral instruments are represented: dispersive grating monochromator, Fourier transform and filter-based spectrometers. More than 2000 data points (combinations of material, wavelength and temperature) were compared. Ninety-eight percent (98%) of the data points were in agreement, with differences to weighted mean values less than the expanded uncertainties calculated from the individual NMI uncertainties and uncertainties related to the comparison process. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  17. Comparison of IR and Visible Cloud Imagers

    NASA Astrophysics Data System (ADS)

    Mandeville, W.; McLaughlin, T.; Bygren, S.; Randell, C.

    This paper presents a comparison between the Infrared Cloud Imager (IRCI) used at Ground-based Electro-Optical Deep Space Surveillance (GEODSS) sites and the Visible Cloud Imager (VCI) developed using a COTS all-sky camera. The cloud imagers are used to create exclusion maps for GEODSS observations based on detected cloud locations. Excluding observation attempts in obscured areas of the sky is done to improve the allocation of sensor resources. Estimates are made for atmospheric extinction across the entire sky by comparing known star brightness to measured brightness. Data for the comparison were collected at the GEODSS test site located in Yoder, Colorado for a variety of cloud conditions.

  18. Systematic Comparison of Operating Reserve Methodologies: Preprint

    SciTech Connect

    Ibanez, E.; Krad, I.; Ela, E.

    2014-04-01

    Operating reserve requirements are a key component of modern power systems, and they contribute to maintaining reliable operations with minimum economic impact. No universal method exists for determining reserve requirements, thus there is a need for a thorough study and performance comparison of the different existing methodologies. Increasing penetrations of variable generation (VG) on electric power systems are posed to increase system uncertainty and variability, thus the need for additional reserve also increases. This paper presents background information on operating reserve and its relationship to VG. A consistent comparison of three methodologies to calculate regulating and flexibility reserve in systems with VG is performed.

  19. Comparison of MMW ground vehicle signatures

    NASA Astrophysics Data System (ADS)

    Saylor, Ph. D., Annie V.; Kissell, Ann

    2006-05-01

    A continuing question asked of MMW target signature and model providers is the applicability of data from one frequency band to another. Recent monopulse Ka-band ground target signature measurements made by US Army programs provide an opportunity to do an in-depth comparison of signatures of several ground vehicles. The vehicles measured correspond to those measured at W-band by another Army program. This paper provides a comparison of vehicle signatures produced by models derived by AMRDEC from the measurements. The results have implications for missile programs that do not have an extensive measurement budget but require target signatures and models for algorithm development.

  20. IASON-FREE: theory and experimental comparisons.

    PubMed

    Felsberger, E; O'Brien, K; Kindl, P

    2009-10-01

    A sophisticated flight code named FREE (acronym for Flight Route Effective Dose Estimation) was built for professional commercial usage. During its creation special precautions have been taken to take correctly into account all existing dependencies and details, so that the best possible result is achieved. Some of these factors are presented in detail and their effect on doses or dose rates is estimated. Detailed comparisons to more recent measurements for both quiescent as well as disturbed conditions are presented. The agreement at undisturbed conditions turns out to be excellent and also the comparisons to measured transient effects are very satisfactory.

  1. Metrics for comparison of crystallographic maps

    SciTech Connect

    Urzhumtsev, Alexandre; Afonine, Pavel V.; Lunin, Vladimir Y.; Terwilliger, Thomas C.; Adams, Paul D.

    2014-10-01

    Numerical comparison of crystallographic contour maps is used extensively in structure solution and model refinement, analysis and validation. However, traditional metrics such as the map correlation coefficient (map CC, real-space CC or RSCC) sometimes contradict the results of visual assessment of the corresponding maps. This article explains such apparent contradictions and suggests new metrics and tools to compare crystallographic contour maps. The key to the new methods is rank scaling of the Fourier syntheses. The new metrics are complementary to the usual map CC and can be more helpful in map comparison, in particular when only some of their aspects, such as regions of high density, are of interest.

  2. 1998 MWD/LWD comparison tables

    SciTech Connect

    1998-05-01

    This year`s comparison tables feature an updated Quick Reference Guide listing MWD sensors by collar size for each manufacturer. Following the Quick Reference Guide are the comparison tables, which list general, directional, gamma ray, resistivity, density and neutron data for each tool. The MWD Tables should only be used as a reference source. System specifications frequently change as tools are refined and developed. Please consult representatives for each company prior to making final tool selections. A contact key for all the companies is included.

  3. On relative distortion in fingerprint comparison.

    PubMed

    Kalka, Nathan D; Hicklin, R Austin

    2014-11-01

    When fingerprints are deposited, non-uniform pressure in conjunction with the inherent elasticity of friction ridge skin often causes linear and non-linear distortions in the ridge and valley structure. The effects of these distortions must be considered during analysis of fingerprint images. Even when individual prints are not notably distorted, relative distortion between two prints can have a serious impact on comparison. In this paper we discuss several metrics for quantifying and visualizing linear and non-linear fingerprint deformations, and software tools to assist examiners in accounting for distortion in fingerprint comparisons.

  4. Parallel mergs sort using comparison matrices. I

    SciTech Connect

    Romm, Y.E.

    1995-05-01

    The topics discussed in this paper are connected with internal merge sorting by a key (in short, M-sorting or M-sort). Originally developed by von Neumann, this is one of the first sorting methods. It still remains one of the fastest, involving Nlog{sub 2}N comparisons. The purpose of our article is to demonstrate the use of comparison matrices (CMs) for merging in M-sort. While preserving the known advantages of the sequential implementation of M-sort. CMs ensure more efficient use of main memory (one of the known weaknesses of M-sort is its large memory requirements) and effective parallelizability.

  5. Performance comparison of electronic radon monitors.

    PubMed

    Lin, Chi-Feng; Wang, Jeng-Jong; Lin, Shih-Jung; Lin, Chien-Kung

    2013-11-01

    The electronic radon monitors are noted for their convenience and acceptable accuracy. Even so, it is necessary to reassure their data quality regularly. We utilized a performance comparison system for this purpose. The instruments in our laboratories (Alphaguard, RAD7, RTM-2100 and Safety Siren) were tested via the comparison experiments. We conclude that by utilizing this system with the concept of calibration factor, it can be helpful to decide whether to send the monitors back to the original manufacturers for adjustment. PMID:23566805

  6. Consistent Comparisons between Monopoly and Perfect Competition.

    ERIC Educational Resources Information Center

    Skeath, Susan E.; And Others

    1992-01-01

    Identifies inconsistencies in treatments of the perfect competition, monopoly welfare comparison in textbooks for economics instruction. Argues for explanation of how experiments are being conducted and explicit identification of all underlying assumptions. Suggests straightforward analysis of the social cost of monopoly based on a comparison…

  7. COMPARISONS AND CONTRASTS AMONG DIFFERENT SCALED ASSESSMENTS

    EPA Science Inventory

    A comparison of a regional (multi-state) and local (multi-county) scale assessment was done to evaluate similarities and differences in the collection, analysis, and interpretation of landscape data. The study areas included EP A Region 3 a11d a sub-region spanning North and Sout...

  8. Comparison Between Different Notions of Resonances

    NASA Astrophysics Data System (ADS)

    Helffer, Bernard

    Introduction A Brief Review on the Analytic Distortion or Dilation Techniques From the Second Definition From the First Definition Case a. The Analytic Dilation (or Complex Scaling) Case b. The Exterior Scaling Case c. The "Regularized" Exterior Scaling (Hislop and Sigal) Case d. A "Linearized" Analytic Distortion Comparison to the Definition of Resonances by Helffer and Sjöstrand Final Remarks

  9. Measurement of Social Development: An International Comparison

    ERIC Educational Resources Information Center

    Ray, Amal Kanti

    2008-01-01

    PQLI and HDI are the two most popular measures of development, besides per capita income. Over the years, PQLI appears to be not much in use for regional comparisons, especially after the introduction of HDI. While PQLI considers only the physical variables--adult literacy, life expectancy at birth and infant survival rate, HDI has life expectancy…

  10. "Units of Comparison" across Languages, across Time

    ERIC Educational Resources Information Center

    Thomas, Margaret

    2009-01-01

    Lardiere's keynote article adverts to a succession of "units of comparison" that have been employed in the study of cross-linguistic differences, including mid-twentieth-century structural patterns, generative grammar's parameters, and (within contemporary Minimalism) features. This commentary expands on the idea of units of cross-linguistic…

  11. Photographic catalog of selected planetary size comparisons

    NASA Technical Reports Server (NTRS)

    Meszaros, S. P.

    1985-01-01

    Photographs taken by NASA spacecraft, and cartographic products based on these photos, are used to illustrate size comparisons of the planets and moons of the solar system. Global views and prominent geographical features are depicted at the same scale, allowing size relationships to be studied visually.

  12. A comparison of Monte Carlo generators

    SciTech Connect

    Golan, Tomasz

    2015-05-15

    A comparison of GENIE, NEUT, NUANCE, and NuWro Monte Carlo neutrino event generators is presented using a set of four observables: protons multiplicity, total visible energy, most energetic proton momentum, and π{sup +} two-dimensional energy vs cosine distribution.

  13. Multiple Comparison Procedures when Population Variances Differ.

    ERIC Educational Resources Information Center

    Olejnik, Stephen; Lee, JaeShin

    A review of the literature on multiple comparison procedures suggests several alternative approaches for comparing means when population variances differ. These include: (1) the approach of P. A. Games and J. F. Howell (1976); (2) C. W. Dunnett's C confidence interval (1980); and (3) Dunnett's T3 solution (1980). These procedures control the…

  14. Do Young Children Understand Relative Value Comparisons?

    PubMed Central

    Benenson, Joyce F.; Markovits, Henry; Whitmore, Bjorn; Van, Christophe; Margolius, Sara; Wrangham, Richard W.

    2015-01-01

    Many forms of judgments, such as those used in economic games or measures of social comparison, require understanding relative value, as well as the more complex ability to make comparisons between relative values. To examine whether young children can accurately compare relative values, we presented children 4 to 7 years with simple judgments of relative value in two scenarios. Children then were asked to compare the relative values in the two scenarios. Results show that even the youngest children downgraded evaluations of a reward when another has a larger amount, indicating the ability to make relative value judgments. When asked to compare relative values however, only the oldest children were able to make these comparisons consistently. We then extended this analysis to economic game performance. Specifically, previous results using economic games suggest that younger children are more generous than older ones. We replicate this result, and then show that a simple change in procedure, based on the initial study, is sufficient to change young children’s choices. Our results strongly suggest that conclusions regarding young children’s pro-social motives based on relative value comparisons should be viewed cautiously. PMID:25875949

  15. The discovery and comparison of symbolic magnitudes.

    PubMed

    Chen, Dawn; Lu, Hongjing; Holyoak, Keith J

    2014-06-01

    Humans and other primates are able to make relative magnitude comparisons, both with perceptual stimuli and with symbolic inputs that convey magnitude information. Although numerous models of magnitude comparison have been proposed, the basic question of how symbolic magnitudes (e.g., size or intelligence of animals) are derived and represented in memory has received little attention. We argue that symbolic magnitudes often will not correspond directly to elementary features of individual concepts. Rather, magnitudes may be formed in working memory based on computations over more basic features stored in long-term memory. We present a model of how magnitudes can be acquired and compared based on BARTlet, a representationally simpler version of Bayesian Analogy with Relational Transformations (BART; Lu, Chen, & Holyoak, 2012). BARTlet operates on distributions of magnitude variables created by applying dimension-specific weights (learned with the aid of empirical priors derived from pre-categorical comparisons) to more primitive features of objects. The resulting magnitude distributions, formed and maintained in working memory, are sensitive to contextual influences such as the range of stimuli and polarity of the question. By incorporating psychological reference points that control the precision of magnitudes in working memory and applying the tools of signal detection theory, BARTlet is able to account for a wide range of empirical phenomena involving magnitude comparisons, including the symbolic distance effect and the semantic congruity effect. We discuss the role of reference points in cognitive and social decision-making, and implications for the evolution of relational representations.

  16. Inter-comparison of subglacial hydrological models

    NASA Astrophysics Data System (ADS)

    de Fleurian, Basile; Werder, Mauro

    2016-04-01

    The recent emergence of a number of subglacial hydrological models allows us to obtain theoretical insights on basal processes; for instance on the coupling between water pressure and the sliding of glaciers. In ice-flow models, it is relatively clear what the simulated physics ought to be. Conversely, the physical processes incorporated into subglacial hydrology models are diverse as it is yet unclear which ones are of relevance for a particular setting. An inter-comparison of hydrology models will therefore need a somewhat different approach to the one used in the many ice-flow model inter-comparisons (EISMINT, ISMIP, etc.). Here, we present a set of experiments that will allow the comparison of the behavior of different hydrology models. The design of the benchmark aims at allowing the participation of a wide range of models based on different physical approaches. We aim at evaluating the models with a focus on the effective pressure which has the most impact on the dynamics of glaciers. The aim of this inter-comparison is to provide modellers with the necessary data to make an informed decision on which subglacial hydrology model to use for a particular study.

  17. ABL and BAM Friction Analysis Comparison

    DOE PAGES

    Warner, Kirstin F.; Sandstrom, Mary M.; Brown, Geoffrey W.; Remmers, Daniel L.; Phillips, Jason J.; Shelley, Timothy J.; Reyes, Jose A.; Hsu, Peter C.; Reynolds, John G.

    2014-12-29

    Here, the Integrated Data Collection Analysis (IDCA) program has conducted a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here is a comparison of the Alleghany Ballistic Laboratory (ABL) friction data and Bundesanstalt fur Materialforschung und -prufung (BAM) friction data for 19 HEM and military standard explosives.

  18. Social Comparison of Pay and Inequity Theory.

    ERIC Educational Resources Information Center

    Judd, Ben

    Inequity theory differs from social exchange theory in its analysis of a worker's reaction to pay by asserting that effects on work performance caused by high or low pay are due to social comparison of fairness rather than principles of direct exchange, such as reciprocity and power. The present experiment held piece-rate pay constant at two…

  19. International Comparisons and Sensitivity to Instruction

    ERIC Educational Resources Information Center

    Wiliam, Dylan

    2008-01-01

    While international comparisons such as those provided by PISA may be meaningful in terms of overall judgements about the performance of educational systems, caution is needed in terms of more fine-grained judgements. In particular it is argued that the results of PISA to draw conclusions about the quality of instruction in different systems is…

  20. 78 FR 38075 - International Labor Comparisons

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... Comparisons (ILC) program adjusted foreign data to a common framework of concepts, definitions, and... Productivity and Technology, Bureau of Labor Statistics, Room 2120, 2 Massachusetts Avenue NE., Washington, DC... Productivity and Technology, Bureau of Labor Statistics, telephone number 202-691-6304 (this is not a toll...

  1. Benefits of State-by-State Comparisons.

    ERIC Educational Resources Information Center

    Phillips, Gary W.

    1991-01-01

    Suggests that the National Assessment of Educational Progress's (NAEP) Trial State Assessment (TSA) will provide reliable and valid state-by-state comparisons of what students have learned and will assess their progress over time. The TSA will also provide information on home learning environments, instructional practices, educational resources,…

  2. What's Wrong with Media Comparison Studies?

    ERIC Educational Resources Information Center

    Surry, Daniel W.; Ensminger, David

    2001-01-01

    Reviews the use of media comparison studies in the field of educational technology, argues that they are weak and inappropriate, and recommends a new focus on the issues of instructional methods and learner characteristics. Discusses intra-medium studies and aptitude treatment interaction studies as better alternatives. (LRW)

  3. Analysis of Paired Comparison Data Using Mx

    ERIC Educational Resources Information Center

    Tsai, Rung-Ching; Wu, Tsung-Lin

    2004-01-01

    By postulating that the random utilities associated with the choice options follow a multivariate normal distribution, Thurstonian models (Thurstone, 1927) provide a straightforward representation of paired comparison data. The use of Monte Carlo Expectation-Maximization (MCEM) algorithms and limited information approaches have been proposed to…

  4. Comparison of Classical and Quantum Mechanical Uncertainties.

    ERIC Educational Resources Information Center

    Peslak, John, Jr.

    1979-01-01

    Comparisons are made for the particle-in-a-box, the harmonic oscillator, and the one-electron atom. A classical uncertainty principle is derived and compared with its quantum-mechanical counterpart. The results are discussed in terms of the statistical interpretation of the uncertainty principle. (Author/BB)

  5. Cross-Cultural Comparisons: The Validity of Assessment by Indices of Factor Comparison.

    ERIC Educational Resources Information Center

    Eysenck, Hans J.

    1986-01-01

    Considers the cross-cultural consistency of personality inventories, concluding that it is justifiable to use the scale of the Eysenck Personality Questionnaire for comparisons within and between different countries. (Author/LHW)

  6. An Analysis of Comparison Questions in the Context of Auditing.

    ERIC Educational Resources Information Center

    Lauer, Thomas W.; Peacock, Eileen

    1990-01-01

    Provides a definition of comparison questions and shows how they relate to the semantic categories of two taxonomies for classifying questions, both of which omit comparison questions. Examines the comparison questions that auditors generate when they diagnose problems in a company. (SR)

  7. The Performance versus Ability Distinction Following Social Comparison Feedback

    ERIC Educational Resources Information Center

    Buckingham, Justin T.; LeBeau, Lavonia Smith; Klein, William M. P.

    2011-01-01

    Previous research suggests that self-evaluations can be influenced by social comparison feedback. The present study tested whether social comparison feedback has stronger effects on self-evaluations of performance than ability. Participants received social comparison feedback indicating that they had performed above or below average. In addition…

  8. Comparison versus Contrast: Task Specifics Affect Category Acquisition

    ERIC Educational Resources Information Center

    Ankowski, Amber A.; Vlach, Haley A.; Sandhofer, Catherine M.

    2013-01-01

    A large literature has documented that comparison and contrast lead to better performance in a variety of tasks. However, studies of comparison and contrast present contradictory conclusions as to when and how these processes benefit learners. Across four studies, we examined how the specifics of the comparison and contrast task affect performance…

  9. 30 CFR 1206.155 - Accounting for comparison.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Accounting for comparison. 1206.155 Section... INTERIOR Natural Resources Revenue PRODUCT VALUATION Federal Gas § 1206.155 Accounting for comparison. (a... with § 1206.152 of this subpart. (b) The requirement for accounting for comparison contained in...

  10. Robot Trajectories Comparison: A Statistical Approach

    PubMed Central

    Ansuategui, A.; Arruti, A.; Susperregi, L.; Yurramendi, Y.; Jauregi, E.; Lazkano, E.; Sierra, B.

    2014-01-01

    The task of planning a collision-free trajectory from a start to a goal position is fundamental for an autonomous mobile robot. Although path planning has been extensively investigated since the beginning of robotics, there is no agreement on how to measure the performance of a motion algorithm. This paper presents a new approach to perform robot trajectories comparison that could be applied to any kind of trajectories and in both simulated and real environments. Given an initial set of features, it automatically selects the most significant ones and performs a statistical comparison using them. Additionally, a graphical data visualization named polygraph which helps to better understand the obtained results is provided. The proposed method has been applied, as an example, to compare two different motion planners, FM2 and WaveFront, using different environments, robots, and local planners. PMID:25525618

  11. Bayesian hypothesis testing for key comparisons

    NASA Astrophysics Data System (ADS)

    Wübbeler, Gerd; Bodnar, Olha; Elster, Clemens

    2016-08-01

    Unilateral degrees of equivalence are the key result in the analysis of key comparison data and they are used to approve, or disapprove, calibration and measurement capabilities of the participating laboratories. To this end, it is checked whether a degree of equivalence differs significantly from zero. Proceeding in such a way can be viewed as carrying out a classical hypothesis test. We develop a Bayesian counterpart to this approach which has the advantage that it can include prior assessment of the corresponding Consultative Committee about the calibration and measurement capabilities of the participating laboratories. Simple expressions are derived and their implementation is provided in terms of MATLAB® and R programs. The novel procedure is illustrated by its application to two recent key comparisons CCL-K1 and CCM.FF-K4.1.2011.

  12. Robot trajectories comparison: a statistical approach.

    PubMed

    Ansuategui, A; Arruti, A; Susperregi, L; Yurramendi, Y; Jauregi, E; Lazkano, E; Sierra, B

    2014-01-01

    The task of planning a collision-free trajectory from a start to a goal position is fundamental for an autonomous mobile robot. Although path planning has been extensively investigated since the beginning of robotics, there is no agreement on how to measure the performance of a motion algorithm. This paper presents a new approach to perform robot trajectories comparison that could be applied to any kind of trajectories and in both simulated and real environments. Given an initial set of features, it automatically selects the most significant ones and performs a statistical comparison using them. Additionally, a graphical data visualization named polygraph which helps to better understand the obtained results is provided. The proposed method has been applied, as an example, to compare two different motion planners, FM(2) and WaveFront, using different environments, robots, and local planners. PMID:25525618

  13. Comparison of stereoscopic technologies in various configurations

    NASA Astrophysics Data System (ADS)

    Fliegel, Karel; Vítek, Stanislav; Jindra, Tomáš; Páta, Petr; Klíma, Miloš

    2012-10-01

    The aim of this paper is twofold. In the first part of the paper we present results of subjective quality assessment based comparison of stereoscopic technologies in various configurations. Subjective assessment has been done on a limited set of observers while using a database of stereoscopic test videos of various source types. There is also comparison of results obtained with the same stereoscopic content from the two cooperating test laboratories. The results can be used to address different aspects of viewing experience, especially comparing passive and active stereoscopic display technologies. The second part of the paper is focused on preliminary experimental results analyzing the vergence-accommodation conflict present in current stereoscopic systems. Simultaneous measurement of the vergence and accommodation has been done with observers viewing a real scene and its stereoscopic reproduction.

  14. Comparison of fugitive coal dust sizing techniques

    SciTech Connect

    Meyer, J.H.; Lenkevich, M.J.; Davis, E.A.

    1984-10-01

    In conjunction with a field-test program to measure fugitive dust emissions from a rotary railcar dumper, several techniques for particle sizing were compared. The comparison experiments were done at Potomac Electric Power Company's coal-fired generating station at Morgantown, Maryland with support of the Maryland Power Plant Siting Program. Three cascade impactor instruments were compared, including a quartz-crystal microbalance. In addition, two other methods, a 40mm millipore filter operated isokinetically and a rotary arm impactor, were used to obtain particulate samples for optical sizing from calibrated microphotographs. The microphotographs also provided information on coal-particle shape, aggregation, and friability. An aerodynamic particle sizer based on laser velocimetry was also used during one of three comparison tests. Two particle resuspension and sizing methods were attempted but abandoned due to experimental difficulties. Coal particle size and cumulative mass-fraction size distributions for the various sampling techniques were compared.

  15. Metrics for comparison of crystallographic maps

    DOE PAGES

    Urzhumtsev, Alexandre; Afonine, Pavel V.; Lunin, Vladimir Y.; Terwilliger, Thomas C.; Adams, Paul D.

    2014-10-01

    Numerical comparison of crystallographic contour maps is used extensively in structure solution and model refinement, analysis and validation. However, traditional metrics such as the map correlation coefficient (map CC, real-space CC or RSCC) sometimes contradict the results of visual assessment of the corresponding maps. This article explains such apparent contradictions and suggests new metrics and tools to compare crystallographic contour maps. The key to the new methods is rank scaling of the Fourier syntheses. The new metrics are complementary to the usual map CC and can be more helpful in map comparison, in particular when only some of their aspects,more » such as regions of high density, are of interest.« less

  16. Robot trajectories comparison: a statistical approach.

    PubMed

    Ansuategui, A; Arruti, A; Susperregi, L; Yurramendi, Y; Jauregi, E; Lazkano, E; Sierra, B

    2014-01-01

    The task of planning a collision-free trajectory from a start to a goal position is fundamental for an autonomous mobile robot. Although path planning has been extensively investigated since the beginning of robotics, there is no agreement on how to measure the performance of a motion algorithm. This paper presents a new approach to perform robot trajectories comparison that could be applied to any kind of trajectories and in both simulated and real environments. Given an initial set of features, it automatically selects the most significant ones and performs a statistical comparison using them. Additionally, a graphical data visualization named polygraph which helps to better understand the obtained results is provided. The proposed method has been applied, as an example, to compare two different motion planners, FM(2) and WaveFront, using different environments, robots, and local planners.

  17. 33alloy: comparison between experiment and simulation

    SciTech Connect

    Kramer, M J; Mendelev, M I; Asta, M

    2014-04-22

    We report data on the structure of liquid Al and an Al67Mg33 alloy obtained from state-of-the-art X-ray diffraction experiments and ab initio molecular dynamics (AIMD) simulations. To facilitate a direct comparison between these data, we develop a method to elongate the AIMD pair correlation function in order to obtain reliable AIMD structure factors. The comparison reveals an appreciable level of discrepancy between experimental and AIMD liquid structures, with the latter being consistently more ordered than the former at the same temperature. The discrepancy noted in this study is estimated to have significant implications for simulation-based calculations of liquid transport properties and solid–liquid interface kinetic properties.

  18. Visual comparison testing of automotive paint simulation

    NASA Astrophysics Data System (ADS)

    Meyer, Gary; Fan, Hua-Tzu; Seubert, Christopher; Evey, Curtis; Meseth, Jan; Schnackenberg, Ryan

    2015-03-01

    An experiment was performed to determine whether typical industrial automotive color paint comparisons made using real physical samples could also be carried out using a digital simulation displayed on a calibrated color television monitor. A special light booth, designed to facilitate evaluation of the car paint color with reflectance angle, was employed in both the real and virtual color comparisons. Paint samples were measured using a multi-angle spectrophotometer and were simulated using a commercially available software package. Subjects performed the test quicker using the computer graphic simulation, and results indicate that there is only a small difference between the decisions made using the light booth and the computer monitor. This outcome demonstrates the potential of employing simulations to replace some of the time consuming work with real physical samples that still characterizes material appearance work in industry.

  19. Rocket/Nimbus Sounder Comparison (RNSC)

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The experimental results for radiance and temperature differences in the Wallops Island comparisons indicate that the differences between satellite and rocket systems are of the same order of magnitude as the differences among the various satellite and rocket sounders. The Arcasondes produced usable data to about 50 km, while the Datasondes require design modification. The SIRS and IRIS soundings provided usable data to 30 mb; extension of these soundings was also investigated.

  20. Comparison of STIS and SNAP spectrograph throughputs

    SciTech Connect

    Aldering, Greg

    2002-06-30

    This is a comparison of the measured throughput of STIS on HST versus what we might expect from the spectrograph on SNAP. The principle reference is Woodgate et al. (1998) PASP, 110, 1183. Additional material was taken from the STIS Handbook, available on-line at www.stsci.edu. The goal is to demonstrate that there are sound reasons to expect better performance for a SNAP spectrograph (even one with a grating) than would be expected by scaling from HST+STIS.

  1. Supercomputers and biological sequence comparison algorithms.

    PubMed

    Core, N G; Edmiston, E W; Saltz, J H; Smith, R M

    1989-12-01

    Comparison of biological (DNA or protein) sequences provides insight into molecular structure, function, and homology and is increasingly important as the available databases become larger and more numerous. One method of increasing the speed of the calculations is to perform them in parallel. We present the results of initial investigations using two dynamic programming algorithms on the Intel iPSC hypercube and the Connection Machine as well as an inexpensive, heuristically-based algorithm on the Encore Multimax.

  2. Spectral comparisons of sunlight and different lamps

    NASA Technical Reports Server (NTRS)

    Deitzer, Gerald

    1994-01-01

    The tables in this report were compiled to characterize the spectra of available lamp types and provide comparison to the spectra of sunlight. Table 1 reports the spectral distributions for various lamp sources and compares them to those measured for sunlight. Table 2 provides the amount of energy in Wm(exp -2) relative to the number of photons of PAR (photosynthetically active radiation) (400-700 nm) for each light source.

  3. Comparison of two dissimilar modal identification techniques

    NASA Technical Reports Server (NTRS)

    Pappa, Richard S.; Schenk, Axel; Niedbal, Norbert; Klusowski, Erhard

    1992-01-01

    Recent laboratory results using a refined phase resonance method and the eigensystem realization algorithm on the same test structure are reported. These methods are dissimilar modal identification techniques suitable for future large spacecraft. The theory, application approach, and results obtained for each technique are summarized and compared. Although both methods worked well in this investigation, significant differences occurred in some identified mode shapes. Comparison of independently derived modal parameters provides the means for disclosing such discrepancies in flight projects.

  4. Sequence comparisons via algorithmic mutual information.

    PubMed

    Milosavljević, A

    1994-01-01

    One of the main problems in DNA and protein sequence comparisons is to decide whether observed similarity of two sequences should be explained by their relatedness or by mere presence of some shared internal structure, e.g., shared internal tandem repeats. The standard methods that are based on statistics or classical information theory can be used to discover either internal structure or mutual sequence similarity, but cannot take into account both. Consequently, currently used methods for sequence comparison employ "masking" techniques that simply eliminate sequences that exhibit internal repetitive structure prior to sequence comparisons. The "masking" approach precludes discovery of homologous sequences of moderate or low complexity, which abound at both DNA and protein levels. As a solution to this problem, we propose a general method that is based on algorithmic information theory and minimal length encoding. We show that algorithmic mutual information factors out the sequence similarity that is due to shared internal structure and thus enables discovery of truly related sequences. We extend that recently developed algorithmic significance method (Milosavljević & Jurka 1993) to show that significance depends exponentially on algorithmic mutual information.

  5. On the role of code comparisons in verification and validation.

    SciTech Connect

    Oberkampf, William Louis; Trucano, Timothy Guy; Pilch, Martin M.

    2003-08-01

    This report presents a perspective on the role of code comparison activities in verification and validation. We formally define the act of code comparison as the Code Comparison Principle (CCP) and investigate its application in both verification and validation. One of our primary conclusions is that the use of code comparisons for validation is improper and dangerous. We also conclude that while code comparisons may be argued to provide a beneficial component in code verification activities, there are higher quality code verification tasks that should take precedence. Finally, we provide a process for application of the CCP that we believe is minimal for achieving benefit in verification processes.

  6. Overview of Recent Radiation Transport Code Comparisons for Space Applications

    NASA Astrophysics Data System (ADS)

    Townsend, Lawrence

    Recent advances in radiation transport code development for space applications have resulted in various comparisons of code predictions for a variety of scenarios and codes. Comparisons among both Monte Carlo and deterministic codes have been made and published by vari-ous groups and collaborations, including comparisons involving, but not limited to HZETRN, HETC-HEDS, FLUKA, GEANT, PHITS, and MCNPX. In this work, an overview of recent code prediction inter-comparisons, including comparisons to available experimental data, is presented and discussed, with emphases on those areas of agreement and disagreement among the various code predictions and published data.

  7. KEY COMPARISON: Key comparison CCQM-K29: Anion calibration solutions: final report

    NASA Astrophysics Data System (ADS)

    Weber, Michael; Wüthrich, Jürg

    2006-01-01

    In this key comparison anion calibration solutions of chloride and phosphate were investigated. The contents of both solutions were about 1 g/kg relative to the anion mass. For the chloride comparison 10 participants provided results by the following three analytical techniques: coulometry, titrimetry and ion chromatography. The phosphate amount content was determined by 10 NMIs whereby the following 6 techniques were applied: ion chromatography, titrimetry, ICP-OES, gravimetry, UV-Vis and ion-exchange followed by coulometry. The following institutes participated in this key comparison: BAM and PTB (Germany) BNM-LNE (France) CENAM (Mexico) EMPA (Switzerland) GUM (Poland) INTEC (Chile) KRISS (Korea) NMIJ (Japan) NRCCRM (China) SMU (Slovakia) With one exception all results were found within the range of +/-0.25% with respect to the gravimetric value. The variability (RSD) of the results is below 0.1% for both the chloride and the phosphate solution (chloride without CENAM result). Compared to the pilot study CCQM-P32 the results of CCQM-K29 were significantly better. This is especially true for the phosphate comparison. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  8. Social comparisons in novel situations: finding inspiration during life transitions.

    PubMed

    Lockwood, Penelope; Shaughnessy, Sarah C; Fortune, Jennifer L; Tong, Man-On

    2012-08-01

    The authors propose that individuals transitioning to a novel environment will prefer upward comparisons, particularly those made with individuals who have experienced a similar transition. Such comparisons help to reduce uncertainty and demonstrate that future success is possible. Study 1 found that individuals facing transitions to unfamiliar situations seek upward comparisons as a result of their uncertainty. Study 2 demonstrated that individuals who perceive themselves to be making a significant life transition are especially motivated by upward comparisons. Study 3 provided evidence that upward comparisons are especially inspiring to individuals making a transition to a novel cultural environment. Study 4 provided experimental evidence that individuals in a novel cultural environment are particularly inspired by upward comparisons with other newcomers. These studies suggest that upward comparisons with individuals who have experienced a similar transition enhance individuals' sense of control over future outcomes and play a key role during adjustment to novel environments. PMID:22825208

  9. Physical appearance comparisons in ethnically diverse college women.

    PubMed

    Schaefer, Lauren M; Thibodaux, Lia K; Krenik, Daniel; Arnold, Elysse; Thompson, J Kevin

    2015-09-01

    Research demonstrates ethnic differences in rates of body dissatisfaction and disordered eating. Appearance comparison frequency is related to these outcomes, however, research has not examined possible ethnic differences in levels of appearance comparisons nor their relation to body dissatisfaction and disordered eating. The current study examined the frequency of appearance comparisons and the strength of the relationships between appearance comparisons, appearance evaluation, and disordered eating among White, Black, and Hispanic women. Measures of appearance comparison, appearance evaluation, and disordered eating were administered to 895 college women. Compared with White and Hispanic women, Black women reported fewer appearance comparisons, more positive appearance evaluation, and lower levels of disordered eating. Associations between examined variables were generally weaker among Black women. Results suggest that the reduced frequency and impact of appearance comparisons may contribute to more positive appearance evaluation and reduced levels of disordered eating among Black women. PMID:26453998

  10. Physical appearance comparisons in ethnically diverse college women.

    PubMed

    Schaefer, Lauren M; Thibodaux, Lia K; Krenik, Daniel; Arnold, Elysse; Thompson, J Kevin

    2015-09-01

    Research demonstrates ethnic differences in rates of body dissatisfaction and disordered eating. Appearance comparison frequency is related to these outcomes, however, research has not examined possible ethnic differences in levels of appearance comparisons nor their relation to body dissatisfaction and disordered eating. The current study examined the frequency of appearance comparisons and the strength of the relationships between appearance comparisons, appearance evaluation, and disordered eating among White, Black, and Hispanic women. Measures of appearance comparison, appearance evaluation, and disordered eating were administered to 895 college women. Compared with White and Hispanic women, Black women reported fewer appearance comparisons, more positive appearance evaluation, and lower levels of disordered eating. Associations between examined variables were generally weaker among Black women. Results suggest that the reduced frequency and impact of appearance comparisons may contribute to more positive appearance evaluation and reduced levels of disordered eating among Black women.

  11. Social comparisons in novel situations: finding inspiration during life transitions.

    PubMed

    Lockwood, Penelope; Shaughnessy, Sarah C; Fortune, Jennifer L; Tong, Man-On

    2012-08-01

    The authors propose that individuals transitioning to a novel environment will prefer upward comparisons, particularly those made with individuals who have experienced a similar transition. Such comparisons help to reduce uncertainty and demonstrate that future success is possible. Study 1 found that individuals facing transitions to unfamiliar situations seek upward comparisons as a result of their uncertainty. Study 2 demonstrated that individuals who perceive themselves to be making a significant life transition are especially motivated by upward comparisons. Study 3 provided evidence that upward comparisons are especially inspiring to individuals making a transition to a novel cultural environment. Study 4 provided experimental evidence that individuals in a novel cultural environment are particularly inspired by upward comparisons with other newcomers. These studies suggest that upward comparisons with individuals who have experienced a similar transition enhance individuals' sense of control over future outcomes and play a key role during adjustment to novel environments.

  12. Comparison of erosion and channel characteristics

    USGS Publications Warehouse

    Parker, Gene W.

    1998-01-01

    Erosion was observed at 33 percent of 22,495 bridge sites in nine States. Among sites with erosion, 56 percent were associated with skewed flows, curved channels, or a combination of these two conditions, and at 18 percent of the sites, channels were straight with steep bank angles. The remaining 26 percent are sites with observable erosion at piers or abutments on straight channels. Comparison of the sites with erosion to channel bed-material indicate that 44 percent of the single-span sites had gravel-size or smaller bed material and 70 percent of the multiple-span sites had gravel-size or smaller bed material.

  13. Comparison of properties of digital spectrometer systems.

    PubMed

    Mazanova, Monika; Dryak, Pavel; Kovar, Petr; Auerbach, Pavel

    2014-05-01

    We have tested two digital spectrometer systems, the DSP 9660 and Lynx(®) modules, connected to a HPGe detector. Lynx(®) is a fully integrated 32K channel signal analyzer based on digital signal processing techniques, which offers advanced digital stabilization. The model DSP 9660 digitalizes the signal directly at a very high sampling rate. The evaluated properties were integral nonlinearity, differential linearity, channel profiles, resolution and throughput. We found that the DSP system has slightly inferior resolution and throughput in comparison with the Lynx(®) system.

  14. A comparison of thermal zone aggregation methods

    SciTech Connect

    Dobbs, Justin R.; Hencey, Brandon M.

    2012-12-10

    The impact of increasing energy prices on building operation budgets has fueled demand for more energy-efficient structures. Existing building energy simulation tools generate an immense amount of data yet comparatively little knowledge. This paper introduces a framework that allows aggregation-based model reduction to operate on geometric building information models. The resulting aggregation sequence provides designers with faster simulations and affords insight into complex multi-scale thermal interactions. A comparison of the trade-off between simulation speed and accuracy for three hierarchical cluster partitioning methods concludes the discussion.

  15. A comparison of RISKIND and RADTRAN 4

    SciTech Connect

    Brumburgh, G.P.; Alesso, H.P.

    1993-11-01

    Our objective in this paper is to provide preliminary comparisons between the two computer codes RISKIND and RADTRAN 4. These codes have utility in evaluating radiological consequences during the transportation of radioactive materials. We reviewed the codes to three criteria: (1) the code`s evaluation capability for accident sequences, frequencies, and environmental consequences, (2) the code`s ``user friendliness`` (as well as how much specific technical expertise the user needed to apply to it), and (3) compatibility with other code output or modules.

  16. Rooftop Unit Comparison Calculator User Manual

    SciTech Connect

    Miller, James D.

    2015-04-30

    This document serves as a user manual for the Packaged rooftop air conditioners and heat pump units comparison calculator (RTUCC) and is an aggregation of the calculator’s website documentation. Content ranges from new-user guide material like the “Quick Start” to the more technical/algorithmic descriptions of the “Methods Pages.” There is also a section listing all the context-help topics that support the features on the “Controls” page. The appendix has a discussion of the EnergyPlus runs that supported the development of the building-response models.

  17. Cross comparison of four DPRK events

    NASA Astrophysics Data System (ADS)

    Bobrov, Dmitry; Kitov, Ivan; Rozhkov, Mikhail

    2016-04-01

    Seismic signals were detected by the IMS seismic network from four announced underground test conducted by the DPRK in 2006, 2009, 2013, and 2016. These data allow thorough comparison of relative locations, including depth estimates, and magnitudes using several techniques based on waveforms cross correlation. Seismic signals from these events also provide waveform templates for detection of possible aftershocks with magnitudes by two-to-three units lower than the events themselves. We have processed one month of continuous data after each of four events and detected no aftershocks. Independent Component Analysis based Blind Source Separation was conducted for all events at different stations to compare the robustness of the source function recovery.

  18. Technoeconomic comparisons of leading hydrogen storage options

    NASA Astrophysics Data System (ADS)

    Carpetis, C.

    The purpose of this paper is to discuss the main features of the leading options for hydrogen storage and to deliver a basic framework for technoeconomic comparisons. From the utilization point of view, several major areas of hydrogen storage (e.g., for large-scale stationary storage, transient storage, onboard storage for vehicular applications) must be considered separately. In each area, more than one storage option (gaseous, liquid, adsorbed, or adsorbed in solid materials) may be economically beneficial. Typical areas of beneficial use and restrictive features will be shown for each of the different storage options.

  19. Multivariate Lipschitz optimization: Survey and computational comparison

    SciTech Connect

    Hansen, P.; Gourdin, E.; Jaumard, B.

    1994-12-31

    Many methods have been proposed to minimize a multivariate Lipschitz function on a box. They pertain the three approaches: (i) reduction to the univariate case by projection (Pijavskii) or by using a space-filling curve (Strongin); (ii) construction and refinement of a single upper bounding function (Pijavskii, Mladineo, Mayne and Polak, Jaumard Hermann and Ribault, Wood...); (iii) branch and bound with local upper bounding functions (Galperin, Pint{acute e}r, Meewella and Mayne, the present authors). A survey is made, stressing similarities of algorithms, expressed when possible within a unified framework. Moreover, an extensive computational comparison is reported on.

  20. Planetary size comparisons: A photographic study

    NASA Technical Reports Server (NTRS)

    Meszaros, S. P.

    1983-01-01

    Over the past two decades NASA spacecraft missions obtained photographs permitting accurate size measurements of the planets and moons, and their surface features. Planetary global views are displayed at the same scale, in each picture to allow visual size comparisons. Additionally, special geographical features on some of the planets are compared with selected Earth areas, again at the same scale. Artist renderings and estimated sizes are used for worlds not yet reached by spacecraft. Included with each picture is number designation for use in ordering copies of the photos.

  1. Intercode comparison of gyrokinetic global electromagnetic modes

    NASA Astrophysics Data System (ADS)

    Görler, T.; Tronko, N.; Hornsby, W. A.; Bottino, A.; Kleiber, R.; Norscini, C.; Grandgirard, V.; Jenko, F.; Sonnendrücker, E.

    2016-07-01

    Aiming to fill a corresponding lack of sophisticated test cases for global electromagnetic gyrokinetic codes, a new hierarchical benchmark is proposed. Starting from established test sets with adiabatic electrons, fully gyrokinetic electrons, and electrostatic fluctuations are taken into account before finally studying the global electromagnetic micro-instabilities. Results from up to five codes involving representatives from different numerical approaches as particle-in-cell methods, Eulerian and Semi-Lagrangian are shown. By means of spectrally resolved growth rates and frequencies and mode structure comparisons, agreement can be confirmed on ion-gyro-radius scales, thus providing confidence in the correct implementation of the underlying equations.

  2. Smythii basin topography and comparisons with Orientale

    NASA Technical Reports Server (NTRS)

    Strain, P. L.; El-Baz, F.

    1979-01-01

    The Smythii basin has the most extensive topographic coverage of any lunar multi-ringed basin. Topographic data are used to study the morphology and morphometry of Smythii and to make comparisons with similar basins. The depth of the basin is shown to be over 8 km, which is comparable to that of Orientale. The inner ring reaches heights of 3.4 km, while the intermediate ring exhibits little relief. Lowest points in the basin are related to mare ridges. Basin volume is estimated to be 21 million cubic kilometers. Evidence suggests that significant differences in substrate characteristics may have existed for the Smythii and Orientale impacts.

  3. Digital signal processing methods for biosequence comparison.

    PubMed Central

    Benson, D C

    1990-01-01

    A method is discussed for DNA or protein sequence comparison using a finite field fast Fourier transform, a digital signal processing technique; and statistical methods are discussed for analyzing the output of this algorithm. This method compares two sequences of length N in computing time proportional to N log N compared to N2 for methods currently used. This method makes it feasible to compare very long sequences. An example is given to show that the method correctly identifies sites of known homology. PMID:2349096

  4. Comparison of Ridges on Triton and Europa

    NASA Technical Reports Server (NTRS)

    Prockter, L. M.; Pappalardo, R. .

    2003-01-01

    Triton and Europa each display a variety of ridges and associated troughs. The resemblance of double ridges on these two satellites has been previously noted [R. Kirk, pers. comm.], but as yet, the similarities and differences between these feature types have not been examined in any detail. Triton s ridges, and Europa s, exhibit an evolutionary sequence ranging from isolated troughs, through doublet ridges, to complex ridge swaths [1, 2]. Comparison of ridges on Europa to those on Triton may provide insight into their formation on both satellites, and thereby have implications for the satellites' histories.

  5. On using the bootstrap for multiple comparisons.

    PubMed

    Westfall, Peter H

    2011-11-01

    There are many ways to bootstrap data for multiple comparisons procedures. Methods described here include (i) bootstrap (parametric and nonparametric) as a generalization of classical normal-based MaxT methods, (ii) bootstrap as an approximation to exact permutation methods, (iii) bootstrap as a generator of realistic null data sets, and (iv) bootstrap as a generator of realistic non-null data sets. Resampling of MinP versus MaxT is discussed, and the use of the bootstrap for closed testing is also presented. Applications to biopharmaceutical statistics are given.

  6. Interior structure of Neptune - Comparison with Uranus

    NASA Technical Reports Server (NTRS)

    Hubbard, W. B.; Nellis, W. J.; Mitchell, A. C.; Holmes, N. C.; Mccandless, P. C.; Limaye, S. S.

    1991-01-01

    Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-called planetary 'ice', have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.

  7. Interior structure of neptune: comparison with uranus.

    PubMed

    Hubbard, W B; Nellis, W J; Mitchell, A C; Holmes, N C; Limaye, S S; McCandless, P C

    1991-08-01

    Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-calied planetary ;;ice,'' have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.

  8. Interior structure of Neptune: Comparison with Uranus

    SciTech Connect

    Hubbard, W.B. ); Nellis, W.J.; Mitchell, A.C.; Holmes, N.C.; McCandless, P.C. ); Limaye, S.S. )

    1991-08-09

    Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-called planetary ice, have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.

  9. Comparison of hyperbolic and hyperboloid conductor electrostatics

    NASA Astrophysics Data System (ADS)

    Lekner, John

    2006-01-01

    The potentials and fields of hyperbolic and hyperboloidal conductors are available analytically. A detailed comparison of the two-dimensional and three-dimensional problems shows strong similarities, but also interesting differences. The electric field near a hyperboloidal needle is stronger (ceteris paribus) than near a hyperbolic blade, and dies off faster. The field at the hyperbolic conductor varies as the 1/3 power of the local curvature. At the hyperboloid conductor the field varies as the 1/4 power of the local Gaussian curvature (which is the product of the two principal curvatures).

  10. A comparison of two ozone sampling methods

    SciTech Connect

    Downey, E.B.; Buchan, R.M.; Blehm, K.D.; Gunter, B.J.

    1983-05-01

    A study was conducted to compare the alkaline potassium iodide (AKI) impinger method versus a direct-reading chemiluminescent monitor for determining ozone concentrations. Comparisons were made in both a controlled laboratory situation and in the field during MIG welding. Laboratoy results indicated that the accuracy of the AKI procedure is affected by sample size. In the field, AKI impinger samples seemed to give very low estimations of the true ozone concentration. The direct-reading chemiluminescent monitor performed excellently in both the laboratory and field, and exhibited its merit as an industrial hygiene field instrument.

  11. Comparison of RESRAD with hand calculations

    SciTech Connect

    Rittmann, P.D.

    1995-09-01

    This report is a continuation of an earlier comparison done with two other computer programs, GENII and PATHRAE. The dose calculations by the two programs were compared with each other and with hand calculations. These band calculations have now been compared with RESRAD Version 5.41 to examine the use of standard models and parameters in this computer program. The hand calculations disclosed a significant computational error in RESRAD. The Pu-241 ingestion doses are five orders of magnitude too small. In addition, the external doses from some nuclides differ greatly from expected values. Both of these deficiencies have been corrected in later versions of RESRAD.

  12. Local and Global Comparison of Continuous Functions

    SciTech Connect

    Edelsbrunner, H; Harer, J; Natarajan, V; Pascucci, V

    2004-12-16

    We introduce local and global comparison measures for a collection of k {<=} d real-valued smooth functions on a common d-dimensional Riemannian manifold. For k = d = 2 we relate the measures to the set of critical points of one function restricted to the level sets of the other. The definition of the measures extends to piecewise linear functions for which they are easy to compute. The computation of the measures forms the centerpiece of a software tool which we use to study scientific datasets.

  13. Classifications and comparisons of multilocus recombination distributions

    PubMed Central

    Karlin, Samuel; Liberman, Uri

    1978-01-01

    Various classifications and representations of multilocus recombination structures are delineated based on generalized notions of linkage values and recombination rates. An important class of recombination distributions (called the count-location chiasma process) is parameterized by a distribution of the number of crossover events and, for each such crossover count, by a conditional distribution of crossover locations. A number of properties of this recombination structure are developed. A multilocus definition of a “natural” recombination range is set forth. Orderings among recombination distributions in the multilocus setting are also discussed. Comparisons are made in terms of complete linkage, free assortment and noninterference schemes serving as standards. PMID:16592601

  14. Quantum Private Comparison Protocol with Linear Optics

    NASA Astrophysics Data System (ADS)

    Luo, Qing-bin; Yang, Guo-wu; She, Kun; Li, Xiaoyu

    2016-09-01

    In this paper, we propose an innovative quantum private comparison(QPC) protocol based on partial Bell-state measurement from the view of linear optics, which enabling two parties to compare the equality of their private information with the help of a semi-honest third party. Partial Bell-state measurement has been realized by using only linear optical elements in experimental measurement-device-independent quantum key distribution(MDI-QKD) schemes, which makes us believe that our protocol can be realized in the near future. The security analysis shows that the participants will not leak their private information.

  15. KEY COMPARISON: Final report on the key comparison CCQM-K48: Assay of potassium chloride

    NASA Astrophysics Data System (ADS)

    Liandi, Ma; Mariassy, Michal; Pratt, Kenneth W.

    2010-01-01

    The CCQM-K48 key comparison for determination of the purity of potassium chloride was organized jointly by the inorganic analysis and electrochemical analysis working groups of CCQM to test the abilities of the metrology institutes to measure the amount content of chloride in KCl. National Institute of Metrology P.R.China (NIM) acted as the coordinating laboratory of this comparison with SMU and NIST as co-coordinating laboratories. Seven NMIs participated in this key comparison. All participants used coulometry (except NMIJ which used gravimetry) and all of them analyzed the impurity bromine in the sample and made corrections. In general very good agreement of the results was observed. Some possible problems were highlighted. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  16. 16 CFR 233.2 - Retail price comparisons; comparable value comparisons.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... comparisons. 233.2 Section 233.2 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES... charged by others for the same merchandise in the advertiser's trade area (the area in which he does... advertiser or by others in the advertiser's trade area for other merchandise of like grade and...

  17. 16 CFR 233.2 - Retail price comparisons; comparable value comparisons.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... comparisons. 233.2 Section 233.2 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES... charged by others for the same merchandise in the advertiser's trade area (the area in which he does... advertiser or by others in the advertiser's trade area for other merchandise of like grade and...

  18. 16 CFR 233.2 - Retail price comparisons; comparable value comparisons.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... comparisons. 233.2 Section 233.2 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES... charged by others for the same merchandise in the advertiser's trade area (the area in which he does... advertiser or by others in the advertiser's trade area for other merchandise of like grade and...

  19. 16 CFR 233.2 - Retail price comparisons; comparable value comparisons.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... comparisons. 233.2 Section 233.2 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES... charged by others for the same merchandise in the advertiser's trade area (the area in which he does... advertiser or by others in the advertiser's trade area for other merchandise of like grade and...

  20. 16 CFR 233.2 - Retail price comparisons; comparable value comparisons.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... comparisons. 233.2 Section 233.2 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES... charged by others for the same merchandise in the advertiser's trade area (the area in which he does... advertiser or by others in the advertiser's trade area for other merchandise of like grade and...

  1. Comparison of State Unemployment Insurance Laws. Comparison Revision, Number 1, August 6, 1978.

    ERIC Educational Resources Information Center

    Employment and Training Administration (DOL), Washington, DC. Unemployment Insurance Service.

    To inform the public about details of the employment security program and how it functions, this comparison of state unemployment insurance laws is presented. The report is based primarily on an analysis of state statutes. It examines state by state the types of workers and employers that are covered under the state law, the methods of financing…

  2. A Comparison of Type I Error Rates of Alpha-Max with Established Multiple Comparison Procedures.

    ERIC Educational Resources Information Center

    Barnette, J. Jackson; McLean, James E.

    J. Barnette and J. McLean (1996) proposed a method of controlling Type I error in pairwise multiple comparisons after a significant omnibus F test. This procedure, called Alpha-Max, is based on a sequential cumulative probability accounting procedure in line with Bonferroni inequality. A missing element in the discussion of Alpha-Max was the…

  3. The interpretation of shoeprint comparison class correspondences.

    PubMed

    Hancock, Sheida; Morgan-Smith, Rian; Buckleton, John

    2012-12-01

    The underlying principles involved in the interpretation of shoeprint comparisons have become a topical subject due to criticisms in the 2009 National Academy of Science (NAS) report on forensic sciences [1]. Difficulties in the application and understanding of these principles were also highlighted in a recent court ruling [2-5]. We report here a survey that may inform some aspects of this interpretation and discuss the implications of findings from this survey in the light of that court ruling and more importantly the NAS report. Five hundred shoeprints taken from student volunteers in Auckland, New Zealand were compared against each other for the presence of any pattern correspondences. Comparisons were undertaken of the full outsole and of smaller portions of the more common patterns. Of the 500 shoe impressions collected 488 (97.6%) were ultimately represented only once in the survey. The greatest number of corresponding patterns was for the most common brand of shoe (Converse Chuck Taylor All Star) and occurred in 3 of 500 observations. No instances of an imitation brand matching the authentic brand were found. Smaller sections of the common patterns showed a greater number of corresponding prints. However, the greatest number of matching partial patterns was again for the most common brand of shoe (Converse Chuck Taylor All Star) and occurred in 29 of 500 observations. We conclude that pattern match alone is of considerable evidential value even when the print is partial. PMID:23068775

  4. Comparison of radar data versus rainfall data

    PubMed Central

    Espinosa, B.; Hromadka, T.V.; Perez, R.

    2015-01-01

    Doppler radar data are increasingly used in rainfall-runoff synthesis studies, perhaps due to radar data availability, among other factors. However, the veracity of the radar data are often a topic of concern. In this paper, three Doppler radar outcomes developed by the United States National Weather Service at three radar sites are examined and compared to actual rain gage data for two separate severe storm events in order to assess accuracy in the published radar estimates of rainfall. Because the subject storms were very intense rainfall events lasting approximately one hour in duration, direct comparisons between the three radar gages themselves can be made, as well as a comparison to rain gage data at a rain gage location subjected to the same storm cells. It is shown that topographic interference with the radar outcomes can be a significant factor leading to differences between radar and rain gage readings, and that care is needed in calibrating radar outcomes using available rain gage data in order to interpolate rainfall estimates between rain gages using the spatial variation observed in the radar readings. The paper establishes and describes•the need for “ground-truthing” of radar data, and•possible errors due to topographic interference. PMID:26649276

  5. Comparison of radar data versus rainfall data.

    PubMed

    Espinosa, B; Hromadka, T V; Perez, R

    2015-01-01

    Doppler radar data are increasingly used in rainfall-runoff synthesis studies, perhaps due to radar data availability, among other factors. However, the veracity of the radar data are often a topic of concern. In this paper, three Doppler radar outcomes developed by the United States National Weather Service at three radar sites are examined and compared to actual rain gage data for two separate severe storm events in order to assess accuracy in the published radar estimates of rainfall. Because the subject storms were very intense rainfall events lasting approximately one hour in duration, direct comparisons between the three radar gages themselves can be made, as well as a comparison to rain gage data at a rain gage location subjected to the same storm cells. It is shown that topographic interference with the radar outcomes can be a significant factor leading to differences between radar and rain gage readings, and that care is needed in calibrating radar outcomes using available rain gage data in order to interpolate rainfall estimates between rain gages using the spatial variation observed in the radar readings. The paper establishes and describes•the need for "ground-truthing" of radar data, and•possible errors due to topographic interference. PMID:26649276

  6. Comparison of radar data versus rainfall data.

    PubMed

    Espinosa, B; Hromadka, T V; Perez, R

    2015-01-01

    Doppler radar data are increasingly used in rainfall-runoff synthesis studies, perhaps due to radar data availability, among other factors. However, the veracity of the radar data are often a topic of concern. In this paper, three Doppler radar outcomes developed by the United States National Weather Service at three radar sites are examined and compared to actual rain gage data for two separate severe storm events in order to assess accuracy in the published radar estimates of rainfall. Because the subject storms were very intense rainfall events lasting approximately one hour in duration, direct comparisons between the three radar gages themselves can be made, as well as a comparison to rain gage data at a rain gage location subjected to the same storm cells. It is shown that topographic interference with the radar outcomes can be a significant factor leading to differences between radar and rain gage readings, and that care is needed in calibrating radar outcomes using available rain gage data in order to interpolate rainfall estimates between rain gages using the spatial variation observed in the radar readings. The paper establishes and describes•the need for "ground-truthing" of radar data, and•possible errors due to topographic interference.

  7. Water gun vs air gun: A comparison

    USGS Publications Warehouse

    Hutchinson, D.R.; Detrick, R. S.

    1984-01-01

    The water gun is a relatively new marine seismic sound source that produces an acoustic signal by an implosive rather than explosive mechanism. A comparison of the source characteristics of two different-sized water guns with those of conventional air guns shows the the water gun signature is cleaner and much shorter than that of a comparable-sized air gun: about 60-100 milliseconds (ms) for an 80-in3. (1.31-liter (I)) water gun compared with several hundred ms for an 80-in3. (1.31-1) air gun. The source spectra of water guns are richer in high frequencies (>200 Hz) than are those of air guns, but they also have less energy than those of air guns at low frequencies. A comparison between water gun and air gun reflection profiles in both shallow (Long Island Sound)-and deep (western Bermuda Rise)-water settings suggests that the water gun offers a good compromise between very high resolution, limited penetration systems (e.g. 3.5-kHz profilers and sparkers) and the large volume air guns and tuned air gun arrays generally used where significant penetration is required. ?? 1984 D. Reidel Publishing Company.

  8. Alternate Propulsion Subsystem Concepts Tripropellant Comparison Study

    NASA Technical Reports Server (NTRS)

    Levack, Daniel

    1995-01-01

    A study was conducted under MSFC contract NAS8-39210 to compare tripropellant and bipropellant engine configurations for the SSTO mission. The objective was to produce an 'apples-to-apples' comparison to isolate the effects of design implementation, designing company, year of design, or technologies included from the basic tripropellant/bipropellant comparison. Consequently, identical technologies were included (e.g., jet pumps) and the same design groundrules and practices were used. Engine power cycles were examined as were turbomachinery/preburner arrangements for each cycle. The bipropellant approach and two tripropellant approaches were separately optimized in terms of operating parameters: exit pressures, mixture ratios, thrust splits, etc. This briefing presents the results of the study including engine weights for both tripropellant and bipropellant engines; dry vehicle weight performance for a range of engine chamber pressures; discusses the basis for the results; examines vehicle performance due to engine cycles and the margin characteristics of various cycles; and identifies technologies with significant payoffs for this application.

  9. Multiple comparison analysis testing in ANOVA.

    PubMed

    McHugh, Mary L

    2011-01-01

    The Analysis of Variance (ANOVA) test has long been an important tool for researchers conducting studies on multiple experimental groups and one or more control groups. However, ANOVA cannot provide detailed information on differences among the various study groups, or on complex combinations of study groups. To fully understand group differences in an ANOVA, researchers must conduct tests of the differences between particular pairs of experimental and control groups. Tests conducted on subsets of data tested previously in another analysis are called post hoc tests. A class of post hoc tests that provide this type of detailed information for ANOVA results are called "multiple comparison analysis" tests. The most commonly used multiple comparison analysis statistics include the following tests: Tukey, Newman-Keuls, Scheffee, Bonferroni and Dunnett. These statistical tools each have specific uses, advantages and disadvantages. Some are best used for testing theory while others are useful in generating new theory. Selection of the appropriate post hoc test will provide researchers with the most detailed information while limiting Type 1 errors due to alpha inflation.

  10. Storage as a Metric of Catchment Comparison

    USGS Publications Warehouse

    McNamara, J.P.; Tetzlaff, D.; Bishop, K.; Soulsby, C.; Seyfried, M.; Peters, N.E.; Aulenbach, Brent T.; Hooper, R.

    2011-01-01

    The volume of water stored within a catchment, and its partitioning among groundwater, soil moisture, snowpack, vegetation, and surface water are the variables that ultimately characterize the state of the hydrologic system. Accordingly, storage may provide useful metrics for catchment comparison. Unfortunately, measuring and predicting the amount of water present in a catchment is seldom done; tracking the dynamics of these stores is even rarer. Storage moderates fluxes and exerts critical controls on a wide range of hydrologic and biologic functions of a catchment. While understanding runoff generation and other processes by which catchments release water will always be central to hydrologic science, it is equally essential to understand how catchments retain water. We have initiated a catchment comparison exercise to begin assessing the value of viewing catchments from the storage perspective. The exercise is based on existing data from five watersheds, no common experimental design, and no integrated modelling efforts. Rather, storage was estimated independently for each site. This briefing presents some initial results of the exercise, poses questions about the definitions and importance of storage and the storage perspective, and suggests future directions for ongoing activities. ?? 2011 John Wiley & Sons, Ltd.

  11. PROCAIN: protein profile comparison with assisting information

    PubMed Central

    Wang, Yong; Sadreyev, Ruslan I.; Grishin, Nick V.

    2009-01-01

    Detection of remote sequence homology is essential for the accurate inference of protein structure, function and evolution. The most sensitive detection methods involve the comparison of evolutionary patterns reflected in multiple sequence alignments (MSAs) of protein families. We present PROCAIN, a new method for MSA comparison based on the combination of ‘vertical’ MSA context (substitution constraints at individual sequence positions) and ‘horizontal’ context (patterns of residue content at multiple positions). Based on a simple and tractable profile methodology and primitive measures for the similarity of horizontal MSA patterns, the method achieves the quality of homology detection comparable to a more complex advanced method employing hidden Markov models (HMMs) and secondary structure (SS) prediction. Adding SS information further improves PROCAIN performance beyond the capabilities of current state-of-the-art tools. The potential value of the method for structure/function predictions is illustrated by the detection of subtle homology between evolutionary distant yet structurally similar protein domains. ProCAIn, relevant databases and tools can be downloaded from: http://prodata.swmed.edu/procain/download. The web server can be accessed at http://prodata.swmed.edu/procain/procain.php. PMID:19357092

  12. PROCAIN: protein profile comparison with assisting information.

    PubMed

    Wang, Yong; Sadreyev, Ruslan I; Grishin, Nick V

    2009-06-01

    Detection of remote sequence homology is essential for the accurate inference of protein structure, function and evolution. The most sensitive detection methods involve the comparison of evolutionary patterns reflected in multiple sequence alignments (MSAs) of protein families. We present PROCAIN, a new method for MSA comparison based on the combination of 'vertical' MSA context (substitution constraints at individual sequence positions) and 'horizontal' context (patterns of residue content at multiple positions). Based on a simple and tractable profile methodology and primitive measures for the similarity of horizontal MSA patterns, the method achieves the quality of homology detection comparable to a more complex advanced method employing hidden Markov models (HMMs) and secondary structure (SS) prediction. Adding SS information further improves PROCAIN performance beyond the capabilities of current state-of-the-art tools. The potential value of the method for structure/function predictions is illustrated by the detection of subtle homology between evolutionary distant yet structurally similar protein domains. ProCAIn, relevant databases and tools can be downloaded from: http://prodata.swmed.edu/procain/download. The web server can be accessed at http://prodata.swmed.edu/procain/procain.php. PMID:19357092

  13. Topology based methods for vector field comparisons

    NASA Astrophysics Data System (ADS)

    Batra, Rajesh Kumar

    Vector fields are commonly found in almost all branches of the physical sciences. Aerodynamics, dynamical systems, electromagnetism, and global climate modeling are a few examples. These multivariate data fields are often large, and no general, automated method exists for comparing these fields. Existing methods require either subjective visual judgments, or data interface compatibility, or domain specific knowledge. A topology based method intrinsically eliminates all of the above limitations and has the additional advantage of significantly compressing the vector field by representing only key features of the flow. Therefore, large databases are compactly represented and quickly searched. Topology is a natural framework for the study of many vector fields. It provides rules of an organizing principle, a flow grammar, that can describe and connect together the properties common to flows. Helman and Hesselink first introduced automated methods to extract and visualize this grammar. This work extends their method by introducing automated methods for vector topology comparison. Basic two-dimensional flows are first compared. The theory is extended to compare three-dimensional flow fields and the topology on no-slip surfaces. Concepts from graph theory and linear programming are utilized to solve these problems. Finally, the first automated method for higher order singularity comparisons is introduced using mathematical theories from geometric (Clifford) algebra.

  14. Bilateral Comparison in Chemosensory-Mediated Foraging

    NASA Astrophysics Data System (ADS)

    Webster, D. R.; Rahman, S.; Dasi, L. P.

    2000-11-01

    Motivation is drawn from the need to determine the sensory cues that animals such as blue crabs and lobsters use to track chemical odor plumes to locate food or mates. Major steps forward with this difficult problem can only be achieved through an appreciation of the spatial and temporal variation of concentration fields and the information content available to a forager in the plume. Here we discuss the usefulness of bilateral comparison to an animal tracking a turbulent plume. Instantaneous concentration fields of a chemical plume diffusing in a fully-developed turbulent open channel flow are measured using planar laser-induced fluorescence (PLIF). The plume is released iso-kinetically 25 mm above the smooth bed (z+ = 90), thus transport is mainly due to advection and ambient turbulence. A spatial correlation function in the spanwise direction is a dramatic indicator of the relative position of the centerline and distance from the source. The relative direction of the plume centerline can be estimated from an instantaneous bilateral comparison provided the sensors are separated by a distance that is relatively large compared to the spanwise integral length scale based on the spatial correlation function.

  15. Cirrus Parcel Model Comparison Project. Phase 1

    NASA Technical Reports Server (NTRS)

    Lin, Ruei-Fong; Starr, David O'C.; DeMott, Paul J.; Cotton, Richard; Jensen, Eric; Sassen, Kenneth

    2000-01-01

    The Cirrus Parcel Model Comparison (CPMC) is a project of the GEWEX Cloud System Study Working Group on Cirrus Cloud Systems (GCSS WG2). The primary goal of this project is to identify cirrus model sensitivities to the state of our knowledge of nucleation and microphysics. Furthermore, the common ground of the findings may provide guidelines for models with simpler cirrus microphysics modules. We focus on the nucleation regimes of the warm (parcel starting at -40 C and 340 hPa) and cold (-60 C and 170 hPa) cases studied in the GCSS WG2 Idealized Cirrus Model Comparison Project. Nucleation and ice crystal growth were forced through an externally imposed rate of lift and consequent adiabatic cooling. The background haze particles are assumed to be lognormally-distributed H2SO4 particles. Only the homogeneous nucleation mode is allowed to form ice crystals in the HN-ONLY runs; all nucleation modes are switched on in the ALL-MODE runs. Participants were asked to run the HN-lambda-fixed runs by setting lambda = 2 (lambda is further discussed in section 2) or tailoring the nucleation rate calculation in agreement with lambda = 2 (exp 1). The depth of parcel lift (800 m) was set to assure that parcels underwent complete transition through the nucleation regime to a stage of approximate equilibrium between ice mass growth and vapor supplied by the specified updrafts.

  16. PROCAIN: protein profile comparison with assisting information.

    PubMed

    Wang, Yong; Sadreyev, Ruslan I; Grishin, Nick V

    2009-06-01

    Detection of remote sequence homology is essential for the accurate inference of protein structure, function and evolution. The most sensitive detection methods involve the comparison of evolutionary patterns reflected in multiple sequence alignments (MSAs) of protein families. We present PROCAIN, a new method for MSA comparison based on the combination of 'vertical' MSA context (substitution constraints at individual sequence positions) and 'horizontal' context (patterns of residue content at multiple positions). Based on a simple and tractable profile methodology and primitive measures for the similarity of horizontal MSA patterns, the method achieves the quality of homology detection comparable to a more complex advanced method employing hidden Markov models (HMMs) and secondary structure (SS) prediction. Adding SS information further improves PROCAIN performance beyond the capabilities of current state-of-the-art tools. The potential value of the method for structure/function predictions is illustrated by the detection of subtle homology between evolutionary distant yet structurally similar protein domains. ProCAIn, relevant databases and tools can be downloaded from: http://prodata.swmed.edu/procain/download. The web server can be accessed at http://prodata.swmed.edu/procain/procain.php.

  17. Final report on CCM key comparison CCM.D-K2: Comparison of liquid density standards

    NASA Astrophysics Data System (ADS)

    Bettin, Horst; Jacques, Claude; Zelenka, Zoltán; Fujii, Ken-ichi; Kuramoto, Naoki; Chang, Kyung-Ho; Lee, Yong Jae; Becerra, Luis Omar; Domostroeva, Natalia

    2013-01-01

    The results are presented of the key comparison CCM.D-K2 that covered the density measurements of four liquids: the density of water at 20 °C, of pentadecane at 15 °C, 20 °C, 40 °C and 60°C, of tetrachloroethlyene at 5 °C and 20 °C and of a viscous oil at 20 °C. Seven national metrology institutes measured the densities at atmospheric pressure by hydrostatic weighing of solid density standards in the time interval from 27 April 2004 to 28 June 2004. Since the participants were asked not to include components for a possible drift or inhomogeneity of the liquid in their uncertainty budget, these uncertainty contributions are investigated for the final evaluation of the data. For this purpose, results of stability and homogeneity measurements of the pilot laboratory are used. The participants decided not to include a possible drift of the liquid's density since no significant drift could be detected, and the influence of the drift and its uncertainty are negligible. Similarly, the inhomogeneity of the water and pentadecane samples is not significant and has no influence on the evaluation. Thus, it was neglected. Only the inhomogeneities of tetrachloroethylene and of the viscous oil were significant. Consequently, they were included in the evaluation. With one or two exceptions, the results show good agreement among the participants. Only in the case of water are the results clearly discrepant. The key comparison reference values were calculated by the weighted mean (taking into account a small correlation between two participants) in the case of consistent results. Otherwise the Procedure B of Cox was used. The expanded uncertainties of all reference densities are below 1 × 10-5 in relative terms. This satisfies the needs of all customers who wish to calibrate or check liquid density measuring instruments such as oscillation-type density meters. The comparison fully supports the calibration measurement capabilities table in the BIPM key comparison database

  18. How social neuroscience can inform theories of social comparison.

    PubMed

    Swencionis, Jillian K; Fiske, Susan T

    2014-04-01

    Social comparison pervades our interactions with others, informing us of our standing and motivating improvement, but producing negative emotional and behavioral consequences that can harm relationships and lead to poor health outcomes. Social neuroscience research has begun to illuminate some mechanisms by which status divides lead to interpersonal consequences. This review integrates core findings on the neuroscience of social comparison processes, showing the effects of comparing the self to relevant others on dimensions of competence and warmth. The literature converges to suggest that relative status divides initiate social comparison processes, that upward and downward comparisons initiate pain- and pleasure-related neural responses, and that these responses can predict people׳s kindly or aggressive intentions toward one another. Across different types of comparisons, brain regions involved in mentalizing are also sometimes involved. Along with future work, the research reviewed here may inform efforts to mitigate negative outcomes of constant social comparisons.

  19. How Social Neuroscience Can Inform Theories of Social Comparison

    PubMed Central

    Swencionis, Jillian K.; Fiske, Susan T.

    2016-01-01

    Social comparison pervades our interactions with others, informing us of our standing and motivating improvement, but producing negative emotional and behavioral consequences that can harm relationships and lead to poor health outcomes. Social neuroscience research has begun to illuminate some mechanisms by which status divides lead to interpersonal consequences. This review integrates core findings on the neuroscience of social comparison processes, showing the effects of comparing the self to relevant others on dimensions of competence and warmth. The literature converges to suggest that relative status divides initiate social comparison processes, that upward and downward comparisons initiate pain- and pleasure- related neural responses, and that these responses can predict people's kindly or aggressive intentions toward one another. Across different types of comparisons, brain regions involved in mentalizing are also sometimes involved. Along with future work, the research reviewed here may inform efforts to mitigate negative outcomes of constant social comparisons. PMID:24486767

  20. A comparison of packaged piezoactuators for industrial applications

    NASA Astrophysics Data System (ADS)

    Pretorius, Jaco; Hugo, Marius; Spangler, Ronald L., Jr.

    2004-07-01

    A comparison of different commercially available packaged piezoelectric actuators is presented. The comparisons are based on force, stress and strain performance at similar field densities. A new metric of comparison, based on energy efficiency, is introduced. This paper provides designers with useful information on actuators and actuator performance for industrial applications. The QuickPack and PowerAct actuators remain the only packaged piezoelectric actuators to be produced in high volume and to feature in commercial applications.

  1. PR Personnel and Print Journalists: A Comparison of Professionalism

    ERIC Educational Resources Information Center

    Nayman, Oguz; And Others

    1977-01-01

    Reports on a comparison of Colorado public relations personnel and newspaper journalists, which focused on demographic characteristics, professional orientation, job satisfaction, and attitude toward professional improvement. (GW)

  2. Remote and Ground Truth Spectral Measurement Comparisons

    NASA Technical Reports Server (NTRS)

    Abercromby, Kira Jorgensen; Hamada, Kris; Guyote, Michael; Okada, Jennifer; Barker, Edwin

    2007-01-01

    FORMOSAT III are a set of six research satellites from Taiwan that were launched in April 2006. The satellites are in 800 km, 71 degree inclination orbits and separated by 24 degrees in ascending node. Ground truth spectral measurements were taken of outer surface materials on FORMOSAT III. From those measurements, a computer model was built to predict the spectral reflectance, which included phase angle and orientation of the spacecraft relative to the observer. However, materials exposed to the space environment have exhibited spectral changes including a darkening and a reddening of the spectra. This reddening was seen as an increase in slope of the reflectance as the wavelength increases. Therefore, the model of pristine materials was augmented to include the space weathering effects. Remote data were collected on two of the six FORMOSAT satellites using the 1.6 meter telescope at AMOS (Air Force Maui Optical and Supercomputing) site with the Spica spectrometer. Due to the separation in ascending node, observations were made on whichever one of the six satellites was visible on that specific night. Three nights of data were collected using the red (6000 9500 angstroms) filter and two nights of data were collected using the blue (3200 -6600 angstroms) filter. A comparison of the data showed a good match to the pristine model for the blue filter region. The absorption feature near 5500 angstroms due to the copper colored Kapton multi-layer insulation (MLI) was very apparent in the remote samples and a good fit to the data was seen in both satellites observed. The features in the red filter regime agreed with the pristine model up through 7000 angstroms where the reddening begins and the slope of the remote sample increases. A comparison of the two satellites showed similar features in the red and blue filter regions, i.e. the satellites were aging at the same rate. A comparison of the pristine model to the first month of remote measurements showed the amount by

  3. Remote and Ground Truth Spectral Measurement Comparisons

    NASA Astrophysics Data System (ADS)

    Abercromby, K.; Hamada, K.; Guyote, M.; Okada, J.; Barker, E.

    FORMOSAT III are a set of six research satellites from Taiwan that were launched in April 2006. The satellites are in 800 km, 71 degree inclination orbits and separated by 24 degrees in ascending node. Laboratory spectral measurements were taken of outer surface materials on FORMOSAT III. From those measurements, a computer model was built to predict the spectral reflectance accounting for both solar phase angle and orientation of the spacecraft relative to the observer. However, materials exposed to the space environment have exhibited spectral changes including a darkening and a "reddening" of the spectra. This "reddening" is characterized by an increase in slope of the reflectance as the wavelength increases. Therefore, the model of pre-flight materials was augmented to include the presumed causative agent: space weathering effects. Remote data were collected on two of the six FORMOSAT satellites using the 1.6 meter telescope at the AMOS (Air Force Maui Optical and Supercomputing) site with the Spica spectrometer. Due to the separation in ascending node, observations were acquired of whichever one of the six satellites was visible on that specific night. Three nights of data were collected using the red (6000 - 9500 angstroms) filter and five nights of data were collected using the blue (3200 -6600 angstroms) filter. A comparison of the data showed a good match to the pre-flight models for the blue filter region. The absorption feature near 5500 angstroms due to the copper colored Kapton multi-layer insulation (MLI) was very apparent in the remote samples and a good fit to the data was seen in all satellites observed. The features in the red filter regime agreed with the pre-flight model up through 7000 angstroms where the reddening begins and the slope of the remote sample increases. A comparison of the satellites showed similar features in the red and blue filter regions, i.e. the satellite surfaces were aging at the same rate. A comparison of the pre

  4. Comparison of metagenomic samples using sequence signatures

    PubMed Central

    2012-01-01

    Background Sequence signatures, as defined by the frequencies of k-tuples (or k-mers, k-grams), have been used extensively to compare genomic sequences of individual organisms, to identify cis-regulatory modules, and to study the evolution of regulatory sequences. Recently many next-generation sequencing (NGS) read data sets of metagenomic samples from a variety of different environments have been generated. The assembly of these reads can be difficult and analysis methods based on mapping reads to genes or pathways are also restricted by the availability and completeness of existing databases. Sequence-signature-based methods, however, do not need the complete genomes or existing databases and thus, can potentially be very useful for the comparison of metagenomic samples using NGS read data. Still, the applications of sequence signature methods for the comparison of metagenomic samples have not been well studied. Results We studied several dissimilarity measures, including d2, d2* and d2S recently developed from our group, a measure (hereinafter noted as Hao) used in CVTree developed from Hao’s group (Qi et al., 2004), measures based on relative di-, tri-, and tetra-nucleotide frequencies as in Willner et al. (2009), as well as standard lp measures between the frequency vectors, for the comparison of metagenomic samples using sequence signatures. We compared their performance using a series of extensive simulations and three real next-generation sequencing (NGS) metagenomic datasets: 39 fecal samples from 33 mammalian host species, 56 marine samples across the world, and 13 fecal samples from human individuals. Results showed that the dissimilarity measure d2S can achieve superior performance when comparing metagenomic samples by clustering them into different groups as well as recovering environmental gradients affecting microbial samples. New insights into the environmental factors affecting microbial compositions in metagenomic samples are obtained through

  5. Comparison of genomic data via statistical distribution.

    PubMed

    Amiri, Saeid; Dinov, Ivo D

    2016-10-21

    Sequence comparison has become an essential tool in bioinformatics, because highly homologous sequences usually imply significant functional or structural similarity. Traditional sequence analysis techniques are based on preprocessing and alignment, which facilitate measuring and quantitative characterization of genetic differences, variability and complexity. However, recent developments of next generation and whole genome sequencing technologies give rise to new challenges that are related to measuring similarity and capturing rearrangements of large segments contained in the genome. This work is devoted to illustrating different methods recently introduced for quantifying sequence distances and variability. Most of the alignment-free methods rely on counting words, which are small contiguous fragments of the genome. Our approach considers the locations of nucleotides in the sequences and relies more on appropriate statistical distributions. The results of this technique for comparing sequences, by extracting information and comparing matching fidelity and location regularization information, are very encouraging, specifically to classify mutation sequences. PMID:27460589

  6. Ozone Profile Comparisons at High Latitudes

    NASA Astrophysics Data System (ADS)

    McPeters, R. D.; Bojkov, B. R.; Deland, M.

    2008-05-01

    Ozone profiles measured by both satellite and ground based instruments at a site at 67.4 N were compared. The measurements were made during the Sodankyla Total Column Ozone Intercomparison (SAUNA) which was held in Sodankyla, Finland in March-April 2006 in support of Aura validation. Measurements by the NOAA 16 SBUV/2 and the Aura MLS instrument were compared with lidar and sonde profiles measured in Sodankyla. Profiles from the satellite instruments generally agreed with profiles from the ground-based instruments to within about 10%. The total column ozone comparisons showed that SBUV/2 and the Aura OMI instrument agreed well with the double Brewer instruments provided the scenes were carefully matched.

  7. Comparison of Kolmogorov's and coherent turbulence.

    PubMed

    Lukin, V P; Bol'basova, L A; Nosov, V V

    2014-04-01

    Features of optical wave fluctuations while propagating through a randomly inhomogeneous turbulent medium with a finite outer scale are considered, including conditions when areas with dominating influence of one large-scale coherent structure are observed in the atmosphere, for which the spectrum of atmospheric turbulence can differ significantly from the Kolmogorov model spectrum. Using an approximate model of the spectrum for coherent turbulence, described earlier in our works, the variance of jitter of an optical image is calculated (under the applicability condition for the smooth perturbation method). The comparison of these equations with known similar equations for Kolmogorov turbulence has shown that the variance of fluctuations is significantly weaker in coherent turbulence than in the Kolmogorov theory under similar conditions. This means that phase fluctuations of optical radiation decrease significantly in coherent turbulence. The importance of this conclusion is noted for interpretation of the results of optical sounding of atmospheric turbulence.

  8. Critical comparison of 3D imaging approaches

    SciTech Connect

    Bennett, C L

    1999-06-03

    Currently three imaging spectrometer architectures, tunable filter, dispersive, and Fourier transform, are viable for imaging the universe in three dimensions. There are domains of greatest utility for each of these architectures. The optimum choice among the various alternative architectures is dependent on the nature of the desired observations, the maturity of the relevant technology, and the character of the backgrounds. The domain appropriate for each of the alternatives is delineated; both for instruments having ideal performance as well as for instrumentation based on currently available technology. The environment and science objectives for the Next Generation Space Telescope will be used as a specific representative case to provide a basis for comparison of the various alternatives.

  9. Comparison of genomic data via statistical distribution.

    PubMed

    Amiri, Saeid; Dinov, Ivo D

    2016-10-21

    Sequence comparison has become an essential tool in bioinformatics, because highly homologous sequences usually imply significant functional or structural similarity. Traditional sequence analysis techniques are based on preprocessing and alignment, which facilitate measuring and quantitative characterization of genetic differences, variability and complexity. However, recent developments of next generation and whole genome sequencing technologies give rise to new challenges that are related to measuring similarity and capturing rearrangements of large segments contained in the genome. This work is devoted to illustrating different methods recently introduced for quantifying sequence distances and variability. Most of the alignment-free methods rely on counting words, which are small contiguous fragments of the genome. Our approach considers the locations of nucleotides in the sequences and relies more on appropriate statistical distributions. The results of this technique for comparing sequences, by extracting information and comparing matching fidelity and location regularization information, are very encouraging, specifically to classify mutation sequences.

  10. Historical comparisons of IRI and early ionograms

    NASA Astrophysics Data System (ADS)

    Rice, Donald; Sojka, Jan J.

    2015-04-01

    The IRI2012 provides ionospheric modeling from 1 January 1958 through the present and near future. However, archives of ionogram films exist dating back to the late 1940s, and are potentially valuable for studying long-term trends and change. IRI is very useful for the analysis and interpretation of the films, so Space Environment Corporation (SEC) has modified IRI2012 to extend its operations back to 1 January 1950. This paper describes results from IRI2012 and observations from the Washington DC ionosonde WA938 (38.7°N, -77.1°E) for 1951 (active post-solar maximum) and 1954 (quiet solar minimum). The comparison shows general agreement between the extended IRI2012 and the ionosonde observations. A nighttime enhancement found in IRI results is observed in some ionograms, with modification by atmospheric waves. A significant discrepancy between IRI and observations was found in nighttime 1954 solar minimum results.

  11. Flexible Substrates Comparison for Pled Technology

    NASA Astrophysics Data System (ADS)

    Nenna, G.; Miscioscia, R.; Tassini, P.; Minarini, C.; Vacca, P.; Valentino, O.

    2008-08-01

    Flexible substrate displays are critical to organic electronics, e-paper's and e-ink's development. Many different types of materials are under investigation, including glass, polymer films and metallic foils. In this work we report a comparison study of polymer films as flexible substrates for polymer light emitting diodes (PLEDs) technology. The selected polymer substrates are two thermoplastic semi-crystalline polymers (PET and PEN) and a high Tg material that cannot be melt processed (PAR). Firstly, the chosen films were characterized in morphology and optical properties with the aim to confirm their suitability for optoelectronic applications. Transmittance was analysed by UV-Vis spectrophotometry and roughness by a surface profilometer. Finally, the surface energy of substrates (untreated and after UV-ozone treatment) was estimated by contact angle measurements in order to evaluate their wettability for active materials deposition.

  12. GCSS Idealized Cirrus Model Comparison Project

    NASA Technical Reports Server (NTRS)

    Starr, David OC.; Benedetti, Angela; Boehm, Matt; Brown, Philip R. A.; Gierens, Klaus; Girard, Eric; Giraud, Vincent; Jakob, Christian; Jensen, Eric; Khvorostyanov, Vitaly; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The GCSS Working Group on Cirrus Cloud Systems (WG2) is conducting a systematic comparison and evaluation of cirrus cloud models. This fundamental activity seeks to support the improvement of models used for climate simulation and numerical weather prediction through assessment and improvement of the "process" models underlying parametric treatments of cirrus cloud processes in large-scale models. The WG2 Idealized Cirrus Model Comparison Project is an initial comparison of cirrus cloud simulations by a variety of cloud models for a series of idealized situations with relatively simple initial conditions and forcing. The models (16) represent the state-of-the-art and include 3-dimensional large eddy simulation (LES) models, two-dimensional cloud resolving models (CRMs), and single column model (SCM) versions of GCMs. The model microphysical components are similarly varied, ranging from single-moment bulk (relative humidity) schemes to fully size-resolved (bin) treatments where ice crystal growth is explicitly calculated. Radiative processes are included in the physics package of each model. The baseline simulations include "warm" and "cold" cirrus cases where cloud top initially occurs at about -47C and -66C, respectively. All simulations are for nighttime conditions (no solar radiation) where the cloud is generated in an ice supersaturated layer, about 1 km in depth, with an ice pseudoadiabatic thermal stratification (neutral). Continuing cloud formation is forced via an imposed diabatic cooling representing a 3 cm/s uplift over a 4-hour time span followed by a 2-hour dissipation stage with no cooling. Variations of these baseline cases include no-radiation and stable-thermal-stratification cases. Preliminary results indicated the great importance of ice crystal fallout in determining even the gross cloud characteristics, such as average vertically-integrated ice water path (IWP). Significant inter-model differences were found. Ice water fall speed is directly

  13. Poultry litter toxicity comparison from various bioassays

    SciTech Connect

    Gupta, G.; Kelly, P. )

    1992-01-01

    Poultry litter contains many toxic chemicals including Cu, As, Pb, Cd, Hg, Se and PCBs. Poultry litter leachate has been shown to be more toxic to marine luminescent organisms (Photobacterium phosphoreum) than other farm animal manures. A comparison of toxicity of the poultry litter leachate was undertaken using various bioassays. The EC{sub 50} (or LC{sub 50}) value for the leachate with the Microtox and Daphnia bioassays was 2.9 g/L/ Nitrobacter and Pseudomonas bioassays were not useful in determining the leachate toxicity because of the nutritional properties of the litter. Poultry litter leachate was found to be mutagenic to strains TA 97, TA 98, TA 100 and TA 102 using the Ames Test.

  14. PhenoBlocks: Phenotype Comparison Visualizations.

    PubMed

    Glueck, Michael; Hamilton, Peter; Chevalier, Fanny; Breslav, Simon; Khan, Azam; Wigdor, Daniel; Brudno, Michael

    2016-01-01

    The differential diagnosis of hereditary disorders is a challenging task for clinicians due to the heterogeneity of phenotypes that can be observed in patients. Existing clinical tools are often text-based and do not emphasize consistency, completeness, or granularity of phenotype reporting. This can impede clinical diagnosis and limit their utility to genetics researchers. Herein, we present PhenoBlocks, a novel visual analytics tool that supports the comparison of phenotypes between patients, or between a patient and the hallmark features of a disorder. An informal evaluation of PhenoBlocks with expert clinicians suggested that the visualization effectively guides the process of differential diagnosis and could reinforce the importance of complete, granular phenotypic reporting.

  15. Quality of life: an international comparison

    SciTech Connect

    Hopkinson, J.; Anderson, C.F.; Liu, B.C.

    1980-04-01

    Dissatisfaction with gross national product (GNP) as a realistic yardstick for comparing the well-being of societies has led to a quality of life (QOL) concept which considers the environment in which people live. QOL includes both the economic and noneconomic factors affecting an individual's happiness. An international comparison of energy, GNP, and QOL in 50 countries considers five major categories (social, economic, health and education, environmental, and national vitality and security) and 12 subcategories. The study indicates that substantial increases in energy consumption will be needed to raise the living standards of developing countries. QOL appears to decline beyond a certain level of GNP, while continuing a direct relationship to per capita energy consumption and electricity production. 12 references. (DCK)

  16. An agreement coefficient for image comparison

    USGS Publications Warehouse

    Ji, L.; Gallo, K.

    2006-01-01

    Combination of datasets acquired from different sensor systems is necessary to construct a long time-series dataset for remotely sensed land-surface variables. Assessment of the agreement of the data derived from various sources is an important issue in understanding the data continuity through the time-series. Some traditional measures, including correlation coefficient, coefficient of determination, mean absolute error, and root mean square error, are not always optimal for evaluating the data agreement. For this reason, we developed a new agreement coefficient for comparing two different images. The agreement coefficient has the following properties: non-dimensional, bounded, symmetric, and distinguishable between systematic and unsystematic differences. The paper provides examples of agreement analyses for hypothetical data and actual remotely sensed data. The results demonstrate that the agreement coefficient does include the above properties, and therefore is a useful tool for image comparison. ?? 2006 American Society for Photogrammetry and Remote Sensing.

  17. Insights from Human/Mouse genome comparisons

    SciTech Connect

    Pennacchio, Len A.

    2003-03-30

    Large-scale public genomic sequencing efforts have provided a wealth of vertebrate sequence data poised to provide insights into mammalian biology. These include deep genomic sequence coverage of human, mouse, rat, zebrafish, and two pufferfish (Fugu rubripes and Tetraodon nigroviridis) (Aparicio et al. 2002; Lander et al. 2001; Venter et al. 2001; Waterston et al. 2002). In addition, a high-priority has been placed on determining the genomic sequence of chimpanzee, dog, cow, frog, and chicken (Boguski 2002). While only recently available, whole genome sequence data have provided the unique opportunity to globally compare complete genome contents. Furthermore, the shared evolutionary ancestry of vertebrate species has allowed the development of comparative genomic approaches to identify ancient conserved sequences with functionality. Accordingly, this review focuses on the initial comparison of available mammalian genomes and describes various insights derived from such analysis.

  18. Code comparison for accelerator design and analysis

    SciTech Connect

    Parsa, Z.

    1988-01-01

    We present a comparison between results obtained from standard accelerator physics codes used for the design and analysis of synchrotrons and storage rings, with programs SYNCH, MAD, HARMON, PATRICIA, PATPET, BETA, DIMAD, MARYLIE and RACE-TRACK. In our analysis we have considered 5 (various size) lattices with large and small angles including AGS Booster (10/degree/ bend), RHIC (2.24/degree/), SXLS, XLS (XUV ring with 45/degree/ bend) and X-RAY rings. The differences in the integration methods used and the treatment of the fringe fields in these codes could lead to different results. The inclusion of nonlinear (e.g., dipole) terms may be necessary in these calculations specially for a small ring. 12 refs., 6 figs., 10 tabs.

  19. Comparison of select reference management tools.

    PubMed

    Zhang, Yingting

    2012-01-01

    Bibliographic management tools have been widely used by researchers to store, organize, and manage their references for research papers, theses, dissertations, journal articles, and other publications. There are a number of reference management tools available. In order for users to decide which tool is best for their needs, it is important to know each tool's strengths and weaknesses. This article compares four reference management tools, one of which is licensed by University of Medicine and Dentistry of New Jersey libraries and the other three are open source and freely available. They were chosen based on their functionality, ease of use, availability to library users, and popularity. These four tools are EndNote/EndNote Web, Zotero, Connotea, and Mendeley Desktop/Mendeley Web. Each tool is analyzed in terms of the following features: accessing, collecting, organizing, collaborating, and citing/formatting. A comparison table is included to summarize the key features of these tools.

  20. Comparison of select reference management tools.

    PubMed

    Zhang, Yingting

    2012-01-01

    Bibliographic management tools have been widely used by researchers to store, organize, and manage their references for research papers, theses, dissertations, journal articles, and other publications. There are a number of reference management tools available. In order for users to decide which tool is best for their needs, it is important to know each tool's strengths and weaknesses. This article compares four reference management tools, one of which is licensed by University of Medicine and Dentistry of New Jersey libraries and the other three are open source and freely available. They were chosen based on their functionality, ease of use, availability to library users, and popularity. These four tools are EndNote/EndNote Web, Zotero, Connotea, and Mendeley Desktop/Mendeley Web. Each tool is analyzed in terms of the following features: accessing, collecting, organizing, collaborating, and citing/formatting. A comparison table is included to summarize the key features of these tools. PMID:22289095

  1. Illicit drug profiling, reflection on statistical comparisons.

    PubMed

    Esseiva, Pierre; Gaste, Laeticia; Alvarez, Daniel; Anglada, Frederic

    2011-04-15

    This paper presents reflexions about statistical considerations on illicit drug profiling and more specifically about the calculation of threshold for determining of the seizure are linked or not. The specific case of heroin and cocaine profiling is presented with the necessary details on the target profiling variables (major alkaloids) selected and the analytical method used. Statistical approach to compare illicit drug seizures is also presented with the introduction of different scenarios dealing with different data pre-treatment or transformation of variables. The main aim consists to demonstrate the influence of data pre-treatment on the statistical outputs. A thorough study of the evolution of the true positive rate (TP) and the false positive rate (FP) in heroin and cocaine comparison is then proposed to investigate this specific topic and to demonstrate that there is no universal approach available and that the calculations have to be revaluate for each new specific application.

  2. Comparison of open source visual analytics toolkits.

    SciTech Connect

    Crossno, Patricia Joyce; Harger, John R.

    2010-11-01

    We present the results of the first stage of a two-stage evaluation of open source visual analytics packages. This stage is a broad feature comparison over a range of open source toolkits. Although we had originally intended to restrict ourselves to comparing visual analytics toolkits, we quickly found that very few were available. So we expanded our study to include information visualization, graph analysis, and statistical packages. We examine three aspects of each toolkit: visualization functions, analysis capabilities, and development environments. With respect to development environments, we look at platforms, language bindings, multi-threading/parallelism, user interface frameworks, ease of installation, documentation, and whether the package is still being actively developed.

  3. A Comparison of Digital Signal Extraction Techniques

    SciTech Connect

    Cunningham, M; Dowla, F

    2004-12-28

    We compare the performance of two methods of digital filtering to detect a radioactive source moving past a gamma-ray sensor. The first method is the box-car filter, which is a standard method used in the detection of a moving radioactive source. The second method is the matched filter, which takes into account the variation in the number of photons absorbed in a gamma-ray sensor as a source moves past the sensor. We optimize both methods to detect a source moving at 5, 10, 15 and 20 mph, and the receiver-operator characteristics of the two techniques are plotted for comparison. The improvement of the matched filter over the box car filter is 27% at 5 mph and 22% at 10 mph for a 90% probability of detection and an average hours between false alarms equal to 10.

  4. Comparison of historical documents for writership

    NASA Astrophysics Data System (ADS)

    Ball, Gregory R.; Pu, Danjun; Stritmatter, Roger; Srihari, Sargur N.

    2010-01-01

    Over the last century forensic document science has developed progressively more sophisticated pattern recognition methodologies for ascertaining the authorship of disputed documents. These include advances not only in computer assisted stylometrics, but forensic handwriting analysis. We present a writer verification method and an evaluation of an actual historical document written by an unknown writer. The questioned document is compared against two known handwriting samples of Herman Melville, a 19th century American author who has been hypothesized to be the writer of this document. The comparison led to a high confidence result that the questioned document was written by the same writer as the known documents. Such methodology can be applied to many such questioned documents in historical writing, both in literary and legal fields.

  5. Secure multiparty computation of a comparison problem.

    PubMed

    Liu, Xin; Li, Shundong; Liu, Jian; Chen, Xiubo; Xu, Gang

    2016-01-01

    Private comparison is fundamental to secure multiparty computation. In this study, we propose novel protocols to privately determine [Formula: see text], or [Formula: see text] in one execution. First, a 0-1-vector encoding method is introduced to encode a number into a vector, and the Goldwasser-Micali encryption scheme is used to compare integers privately. Then, we propose a protocol by using a geometric method to compare rational numbers privately, and the protocol is information-theoretical secure. Using the simulation paradigm, we prove the privacy-preserving property of our protocols in the semi-honest model. The complexity analysis shows that our protocols are more efficient than previous solutions. PMID:27652062

  6. Comparison of Two Recent Launch Abort Platforms

    NASA Technical Reports Server (NTRS)

    Dittemore, Gary D.; Harding, Adam

    2011-01-01

    The development of new and safer manned space vehicles is a top priority at NASA. Recently two different approaches of how to accomplish this mission of keeping astronauts safe was successfully demonstrated. With work already underway on an Apollo-like launch abort system for the Orion Crew Exploration Vehicle (CEV), an alternative design concept named the Max Launch Abort System, or MLAS, was developed as a parallel effort. The Orion system, managed by the Constellation office, is based on the design of a single solid launch abort motor in a tower positioned above the capsule. The MLAS design takes a different approach placing the solid launch abort motor underneath the capsule. This effort was led by the NASA Engineering and Safety Center (NESC). Both escape systems were designed with the Ares I Rocket as the launch vehicle and had the same primary requirement to safely propel a crew module away from any emergency event either on the launch pad or during accent. Beyond these two parameters, there was little else in common between the two projects, except that they both concluded in successful launches that will further promote the development of crew launch abort systems. A comparison of these projects from the standpoint of technical requirements; program management and flight test objectives will be done to highlight the synergistic lessons learned by two engineers who worked on each program. This comparison will demonstrate how the scope of the project architecture and management involvement in innovation should be tailored to meet the specific needs of the system under development.

  7. Vesta: a Comparison with Asteroid 21 Lutetia

    NASA Astrophysics Data System (ADS)

    Skorov, Y. V.; Keller, H.; Mottola, S.; Jorda, L.; Schroeder, S.; Jaumann, R.; Neukum, G.; Marchi, S.

    2011-12-01

    4 Vesta is a miniature (proto) planet. Its nearly spherical shape indicates that it was formed in hydrostatic equilibrium. Vesta is considered the parent body of the HED meteorites, achondrites that experienced extensive igneous processing, and therefore it is expected that Vesta is a differentiated body, probably the smallest of our solar system. The images by the Framing Camera onboard Dawn display a surface with complex topography due to impacts and possibly endogenic processes. Features and processes on the lunar surface are often used for comparison in order to understand the geomorphology and geophysics of Vesta. Vesta's diameter, however, is 6.5 times smaller than that of the Moon. It is comparable to those of other big asteroids and about 5 times the mean diameter of the asteroid 21 Lutetia. Lutetia was recently observed by the Rosetta spacecraft during a flyby. Its mass and volume were determined to yield a density of 3400 kg/m3. The densities of the Moon, Vesta, and Lutetia are similar within the error bars and hence surface gravity and escape velocity scale with the radii of these bodies. These parameters (density, surface gravity, and escape velocity) strongly influence crater forming dynamics. Geomorphologic features on Vesta and Lutetia can be directly compared because the scales of images taken during the Dawn high altitude mapping orbit (HAMO) and those of Rosetta are both about 60 m/pixel. The number densities and properties of impactors should have been rather similar for both asteroids considering their mean heliocentric distances. A direct comparison with Lutetia's properties (shape, geomorphology, crater size distribution, and variegation) will help to constrain parameters of processes on Vesta and possibly be useful to separate exogenic from endogenic effects.

  8. Bayesian model comparison of solar flare spectra

    NASA Astrophysics Data System (ADS)

    Ireland, J.; Holman, G.

    2012-12-01

    The detailed understanding of solar flares requires an understanding of the physics of accelerated electrons, since electrons carry a large fraction of the total energy released in a flare. Hard X-ray energy flux spectral observations of solar flares can be fit with different parameterized models of the interaction of the flare-accelerated electrons with the solar plasma. Each model describes different possible physical effects that may occur in solar flares. Bayesian model comparison provides a technique for assessing which model best describes the data. The advantage of this technique over others is that it can fully account for the different number and type of parameters in each model. We demonstrate this using Ramaty High Energy Solar Spectroscopic Imager (RHESSI) spectral data from the GOES (Geostationary Operational Environmental Satellite) X4.8 flare of 23-July-2002. We suggest that the observed spectrum can be reproduced using two different parameterized models of the flare electron content. The first model assumes that the flare-accelerated electron spectrum consisting of a single power law with a fixed low energy cutoff assumed to be below the range of fitted X-ray energies, interacting with a non-uniformly ionized target. The second model assumes that the flare-accelerated electron spectrum has a broken power law and a low energy cutoff, which interacts with a fully ionized target plasma. The low energy cutoff in this model is a parameter used in fitting the data. We will introduce and use Bayesian model comparison techniques to decide which model best explains the observed data. This work is funded by the NASA Solar and Heliospheric Physics program.

  9. SUPPLEMENTARY COMPARISON Technically enhanced naturally occurring radionuclides (TENORM) in phosphogypsum: Comparison CCRI(II)-S5

    NASA Astrophysics Data System (ADS)

    Shakhashiro, A.; Sansone, U.; Wershofen, H.; Bollhöfer, A.; Kim, C. K.; Kim, C. S.; Korun, M.; Moune, M.; Lee, S. H.; Tarjan, S.

    2010-01-01

    Within the frame of mutual cooperation between the IAEA and the BIPM, the Consultative Committee for Ionizing Radiation Section II—Measurement of Radionuclides accepted an IAEA-organized interlaboratory comparison in 2008 on the determination of technically enhanced naturally occurring radionuclides in phosphogypsum. The study was piloted by the Chemistry Unit at the IAEA's Laboratories in Seibersdorf (Austria). This report presents the methodology applied in conducting this comparison and the results. Activity results for Pb-210, Ra-226, Th-230, U-234, U-235 and U-238 were reported by three national metrology institutes (NMI) and five other expert laboratories or designated institutes. Four different approaches were used to calculate the nominal value of the reported results and associated uncertainties, and the results from each individual participant were evaluated and compared with this nominal reference value. The reported evaluation of the measurement results demonstrated agreement amongst the participating laboratories. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI Section II, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  10. KEY COMPARISON: Final report, on-going key comparison BIPM.QM-K1: Ozone at ambient level, comparison with ISCIII, 2007

    NASA Astrophysics Data System (ADS)

    Viallon, Joële; Moussay, Philippe; Wielgosz, Robert; Morillo Gomez, Pilar; Sánchez Blaya, Carmen

    2009-01-01

    As part of the on-going key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of the Instituto de Salud Carlos III (ISCIII) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone mole fraction range of 0 nmol/mol to 500 nmol/mol. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  11. A Note on Multigroup Comparisons Using SAS PROC CALIS

    ERIC Educational Resources Information Center

    Jones-Farmer, L. Allison; Pitts, Jennifer P.; Rainer, R. Kelly

    2008-01-01

    Although SAS PROC CALIS is not designed to perform multigroup comparisons, it is believed that SAS can be "tricked" into doing so for groups of equal size. At present, there are no comprehensive examples of the steps involved in performing a multigroup comparison in SAS. The purpose of this article is to illustrate these steps. We demonstrate…

  12. Social Comparison Information and Judgments about Depression and Seeking Counseling.

    ERIC Educational Resources Information Center

    Strohmer, Douglas C.; And Others

    1984-01-01

    Used a role playing technique to examine the influence of social comparison on help seeking attitudes in 80 students. Results indicated that subjects who received serious social comparison information reported the highest depression scores and were more willing to seek counseling help. (JAC)

  13. Social Comparison Processes in an Organizational Context: New Directions

    ERIC Educational Resources Information Center

    Goodman, Paul S.; Haisley, Emily

    2007-01-01

    The goal of this article is to frame some new directions to social comparison research in organizational settings. Four themes are developed. First, we examine the role of organizational variables in shaping the basic sub processes in social comparison, such as the selection of referents. The second theme focuses on the meaning of level of…

  14. 30 CFR 1206.155 - Accounting for comparison.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Accounting for comparison. 1206.155 Section 1206.155 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES REVENUE PRODUCT VALUATION Federal Gas § 1206.155 Accounting for comparison. (a) Except as...

  15. 30 CFR 1206.155 - Accounting for comparison.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Accounting for comparison. 1206.155 Section 1206.155 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES REVENUE PRODUCT VALUATION Federal Gas § 1206.155 Accounting for comparison. (a) Except as...

  16. 30 CFR 1206.155 - Accounting for comparison.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Accounting for comparison. 1206.155 Section 1206.155 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES REVENUE PRODUCT VALUATION Federal Gas § 1206.155 Accounting for comparison. (a) Except as...

  17. Using Paired Comparisons to Assess Maslow's Hierarchy of Needs.

    ERIC Educational Resources Information Center

    Strong, Lisa L.; Fiebert, Martin S.

    Past studies which have examined need levels have identified individuals as functioning at specific need levels without an adequate assessment of the intensity of each need or a clear comparison with other need levels. To address these issues, a self-report inventory using a modified paired comparison format was developed to assess need potencies…

  18. Competitive Behavior: A Manifestation of Motivation for Ability Comparison

    ERIC Educational Resources Information Center

    Conolley, Edward S.; And Others

    1978-01-01

    Social comparison theory predicts that when the person is uncertain about the level of his ability, he may seek comparison information through competitive behavior. An experiment is reported in which the level of the subject's uncertainty about his competence was manipulated and subsequent measures of his competitive motivation and behavior were…

  19. 30 CFR 206.155 - Accounting for comparison.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Accounting for comparison. 206.155 Section 206.155 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT PRODUCT VALUATION Federal Gas § 206.155 Accounting for comparison. (a) Except as provided...

  20. [Apples with oranges? Comparison of scientometric indicators between fields].

    PubMed

    Schubert, András

    2016-04-17

    It is well known that all scientometric indicators strongly depend on research fields. Therefore, there is a certain reluctance to make any cross-field comparison of these indicators. The paper reviews the possibilities to normalize the most important scientometric indicators: publication counts, citation rate or h-index, thus making them suitable for cross-field comparison. PMID:27063431

  1. 42 CFR 493.1281 - Standard: Comparison of test results.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 5 2012-10-01 2012-10-01 false Standard: Comparison of test results. 493.1281... Testing Analytic Systems § 493.1281 Standard: Comparison of test results. (a) If a laboratory performs the... between test results using the different methodologies, instruments, or testing sites. (b) The...

  2. 42 CFR 493.1281 - Standard: Comparison of test results.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 5 2011-10-01 2011-10-01 false Standard: Comparison of test results. 493.1281... Testing Analytic Systems § 493.1281 Standard: Comparison of test results. (a) If a laboratory performs the... between test results using the different methodologies, instruments, or testing sites. (b) The...

  3. 42 CFR 493.1281 - Standard: Comparison of test results.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Standard: Comparison of test results. 493.1281... Testing Analytic Systems § 493.1281 Standard: Comparison of test results. (a) If a laboratory performs the... between test results using the different methodologies, instruments, or testing sites. (b) The...

  4. Numerical Order and Quantity Processing in Number Comparison

    ERIC Educational Resources Information Center

    Turconi, Eva; Campbell, Jamie I. D.; Seron, Xavier

    2006-01-01

    We investigated processing of numerical order information and its relation to mechanisms of numerical quantity processing. In two experiments, performance on a quantity-comparison task (e.g. 2 5; which is larger?) was compared with performance on a relative-order judgment task (e.g. 2 5; ascending or descending order?). The comparison task…

  5. Cache-Cache Comparison for Supporting Meaningful Learning

    ERIC Educational Resources Information Center

    Wang, Jingyun; Fujino, Seiji

    2015-01-01

    The paper presents a meaningful discovery learning environment called "cache-cache comparison" for a personalized learning support system. The processing of seeking hidden relations or concepts in "cache-cache comparison" is intended to encourage learners to actively locate new knowledge in their knowledge framework and check…

  6. Comparison of INMARSAT and ATS3 satellite communication

    SciTech Connect

    Not Available

    1993-03-29

    There exists a need to provide communication through a satellite- based network which allows a user to communicate from a remote site to a fixed site. This discussion provides a comparison, both technical and financial, between the existing ATS3 satellite system and the commercial INMARSAT system. This comparison identified the limitations of each system to provide various types of communication.

  7. 16 CFR 233.1 - Former price comparisons.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Former price comparisons. 233.1 Section 233.1 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.1 Former price comparisons. (a) One of the most commonly used forms of...

  8. 16 CFR 233.1 - Former price comparisons.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Former price comparisons. 233.1 Section 233.1 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.1 Former price comparisons. (a) One of the most commonly used forms of...

  9. 16 CFR 233.1 - Former price comparisons.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Former price comparisons. 233.1 Section 233.1 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.1 Former price comparisons. (a) One of the most commonly used forms of...

  10. 16 CFR 233.5 - Miscellaneous price comparisons.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Miscellaneous price comparisons. 233.5 Section 233.5 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.5 Miscellaneous price comparisons. The practices covered in the provisions set...

  11. 16 CFR 233.5 - Miscellaneous price comparisons.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Miscellaneous price comparisons. 233.5 Section 233.5 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.5 Miscellaneous price comparisons. The practices covered in the provisions set...

  12. 16 CFR 233.5 - Miscellaneous price comparisons.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Miscellaneous price comparisons. 233.5 Section 233.5 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.5 Miscellaneous price comparisons. The practices covered in the provisions set...

  13. 16 CFR 233.5 - Miscellaneous price comparisons.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Miscellaneous price comparisons. 233.5 Section 233.5 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.5 Miscellaneous price comparisons. The practices covered in the provisions set...

  14. 16 CFR 233.1 - Former price comparisons.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Former price comparisons. 233.1 Section 233.1 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.1 Former price comparisons. (a) One of the most commonly used forms of...

  15. 16 CFR 233.5 - Miscellaneous price comparisons.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Miscellaneous price comparisons. 233.5 Section 233.5 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.5 Miscellaneous price comparisons. The practices covered in the provisions set...

  16. 16 CFR 233.1 - Former price comparisons.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Former price comparisons. 233.1 Section 233.1 Commercial Practices FEDERAL TRADE COMMISSION GUIDES AND TRADE PRACTICE RULES GUIDES AGAINST DECEPTIVE PRICING § 233.1 Former price comparisons. (a) One of the most commonly used forms of...

  17. Model Comparison of Bayesian Semiparametric and Parametric Structural Equation Models

    ERIC Educational Resources Information Center

    Song, Xin-Yuan; Xia, Ye-Mao; Pan, Jun-Hao; Lee, Sik-Yum

    2011-01-01

    Structural equation models have wide applications. One of the most important issues in analyzing structural equation models is model comparison. This article proposes a Bayesian model comparison statistic, namely the "L[subscript nu]"-measure for both semiparametric and parametric structural equation models. For illustration purposes, we consider…

  18. [Apples with oranges? Comparison of scientometric indicators between fields].

    PubMed

    Schubert, András

    2016-04-17

    It is well known that all scientometric indicators strongly depend on research fields. Therefore, there is a certain reluctance to make any cross-field comparison of these indicators. The paper reviews the possibilities to normalize the most important scientometric indicators: publication counts, citation rate or h-index, thus making them suitable for cross-field comparison.

  19. Comparison of JPL and European Environmental Testing Standards

    NASA Technical Reports Server (NTRS)

    Man, Kin Fung; Forgave, John C.; Hoffman, Alan R.

    2006-01-01

    A comparison of JPL and European environmental testing standards is presented. The contents include: 1) JPL Environmental Testing Documents; 2) Focus of the Comparison; 3) Test Policy; 4) Documentation; 5) Programmatics; 6) Functional Testing; 7) Reporting; 8) Dynamics Test Levels, Durations, & Margins; 9) Thermal Test Levels, Durations, & Margins; and 10) EMC Test Levels, Durations, & Margins.

  20. Learning Radiological Appearances of Diseases: Does Comparison Help?

    ERIC Educational Resources Information Center

    Kok, Ellen M.; de Bruin, Anique B. H.; Robben, Simon G. F.; van Merrienboer, Jeroen J. G.

    2013-01-01

    Comparison learning is a promising approach for learning complex real-life visual tasks. When medical students study radiological appearances of diseases, comparison of images showing diseases with images showing no abnormalities could help them learn to discriminate relevant, disease-related information. Medical students studied 12 diseases on…

  1. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Conducting the comparison study. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  2. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Conducting the comparison study. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  3. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Conducting the comparison study. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  4. 40 CFR 761.326 - Conducting the comparison study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Conducting the comparison study. 761.326 Section 761.326 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...-liquid PCB Remediation Waste Samples § 761.326 Conducting the comparison study. Extract or analyze...

  5. Automatic comparison of striation information on firearm bullets

    NASA Astrophysics Data System (ADS)

    Puente Leon, Fernando; Beyerer, Juergen

    1999-08-01

    This paper deals with an important task within forensic science - the automatic comparison of bullets for the purpose of firearm identification. Bullets bear groove- shaped marks that can be though of as a kind of 'fingerprint' of the firearm on their circumferential surface. To accomplish the comparison task, mainly the fine grooves on the bullet surface are of interests.

  6. Group Comparisons of Mathematics Performance from a Cognitive Diagnostic Perspective

    ERIC Educational Resources Information Center

    Chen, Yi-Hsin; Ferron, John M.; Thompson, Marilyn S.; Gorin, Joanna S.; Tatsuoka, Kikumi K.

    2010-01-01

    Traditional comparisons of test score means identify group differences in broad academic areas, but fail to provide substantive description of how the groups differ on the specific cognitive attributes required for success in the academic area. The rule space method (RSM) allows for group comparisons at the cognitive attribute level, which…

  7. RDV77 VLBA Hardware/Software Correlator Comparisons

    NASA Technical Reports Server (NTRS)

    Gordon, David

    2010-01-01

    Results of a hardware vs. software correlation of the RDV77 session are presented. Group delays are found to agree (WRMS differences) at an average level of 4.2 psec and with a noise floor of 2.5 psec. These RDV77 comparisons agree well with several previous correlator comparison studies.

  8. Optimism, Social Comparisons, and Coping with Vision Loss in Israel

    ERIC Educational Resources Information Center

    Ben-Zur, Hasida; Debi, Zoharit

    2005-01-01

    This study of 90 adults (aged 55?80) who lost their vision assessed their dispositional optimism, social comparisons, coping strategies, and wellbeing. The findings suggest that optimism and positive social comparisons play an important role in stimulating the motivation to cope adaptively with vision loss and that enhancing optimism and social…

  9. Finding a Comparison Group: Is Online Crowdsourcing a Viable Option?

    ERIC Educational Resources Information Center

    Azzam, Tarek; Jacobson, Miriam R.

    2013-01-01

    This article explores the viability of online crowdsourcing for creating matched-comparison groups. This exploratory study compares survey results from a randomized control group to survey results from a matched-comparison group created from Amazon.com's MTurk crowdsourcing service to determine their comparability. Study findings indicate…

  10. Item Response Modeling of Paired Comparison and Ranking Data

    ERIC Educational Resources Information Center

    Maydeu-Olivares, Alberto; Brown, Anna

    2010-01-01

    The comparative format used in ranking and paired comparisons tasks can significantly reduce the impact of uniform response biases typically associated with rating scales. Thurstone's (1927, 1931) model provides a powerful framework for modeling comparative data such as paired comparisons and rankings. Although Thurstonian models are generally…

  11. Unlimited Capacity Parallel Quantity Comparison of Multiple Integers

    ERIC Educational Resources Information Center

    Blanc-Goldhammer, Daryn R.; Cohen, Dale J.

    2014-01-01

    Research has shown that integer comparison is quick and efficient. This efficiency may be a function of the structure of the integer comparison system. The present study tests whether integers are compared with an unlimited capacity system or a limited capacity system. We tested these models using a visual search task with time delimitation. The…

  12. Filter system cost comparison for IGCC and PFBC power systems

    SciTech Connect

    Dennis, R.A.; McDaniel, H.M.; Buchanan, T.

    1995-12-01

    A cost comparison was conducted between the filter systems for two advanced coal-based power plants. The results from this study are presented. The filter system is based on a Westinghouse advanced particulate filter concept, which is designed to operate with ceramic candle filters. The Foster Wheeler second-generation 453 MWe (net) pressurized fluidized-bed combustor (PFBC) and the KRW 458 MWe (net) integrated gasification combined cycle (IGCC) power plants are used for the comparison. The comparison presents the general differences of the two power plants and the process-related filtration conditions for PFBC and IGCC systems. The results present the conceptual designs for the PFBC and IGCC filter systems as well as a cost summary comparison. The cost summary comparison includes the total plant cost, the fixed operating and maintenance cost, the variable operating and maintenance cost, and the effect on the cost of electricity (COE) for the two filter systems.

  13. Final report of supplementary comparison SIM.M.P-S7: Hydraulic pressure comparison from 7 MPa to 70 MPa

    NASA Astrophysics Data System (ADS)

    Gil Romero, Juan Carlos; Catalina Neira, María; Torres Guzmán, Jorge C.

    2013-01-01

    This report presents the final results of supplementary comparison SIM.M.P-S7 in the field of hydraulic pressure up to 70 MPa, within the PTB-ANDIMET-PLUS project. Seven national pressure reference laboratories participated in this comparison, which started with an opening meeting in November 2011 at the city of Lima; the closing meeting was held at the National Metrology Institute of Colombia INM, at Bogota, on 27-28 November 2012. Each participating laboratory used for the comparison its best hydraulic pressure balance standard in the range from 7 MPa to 70 MPa. The transfer standard for the comparison was a digital manometer DH Instruments Fluke RPM-4 with an accuracy of 0.008% of the reading. The reference laboratory and advisor for the comparison was CENAM, Mexico. The comparison protocol and results analysis was made by the pressure laboratory of National Metrology Institute INM (Colombia) who participated in the comparison as well. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by SIM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  14. Watershed comparison beyond rainfall-runoff analysis

    NASA Astrophysics Data System (ADS)

    McGlynn, B. L.; Weiler, M.

    2004-05-01

    Comparing runoff response and runoff generation processes among catchments not only requires rainfall and runoff data, but more importantly, additional process knowledge and tools to quantify similarity/difference. Isotopic hydrograph separation is a well established tool to help elucidate runoff processes, but is a poor tool for quantitative catchment comparison. Unit hydrograph analysis is a good tool to quantify catchment response, but provides little processes information. We developed the TRANSEP model to combine the positive merits of hydrograph separation and unit hydrograph analysis (Weiler et al., 2003, WRR). Application of TRANSEP to measured rainfall runoff events and associated tracer data allows quantification of the runoff response and separation of the runoff response into its event and pre-event water components. In addition, the effective precipitation and the precipitation that reaches the stream can be determined. We applied TRANSEP to two storms in four catchments ranging in size from 2.6 ha to 280 ha size at the Maimai research watersheds (NZ). We demonstrate the performance of TRANSEP in quantifying the tracer response, runoff response, and event water contribution across catchment scale. TRANSEP offers a new approach for quantifying catchment hydrology and comparing watersheds based on runoff processes and response characteristics.

  15. Method and apparatus for biological sequence comparison

    DOEpatents

    Marr, Thomas G.; Chang, William I-Wei

    1997-01-01

    A method and apparatus for comparing biological sequences from a known source of sequences, with a subject (query) sequence. The apparatus takes as input a set of target similarity levels (such as evolutionary distances in units of PAM), and finds all fragments of known sequences that are similar to the subject sequence at each target similarity level, and are long enough to be statistically significant. The invention device filters out fragments from the known sequences that are too short, or have a lower average similarity to the subject sequence than is required by each target similarity level. The subject sequence is then compared only to the remaining known sequences to find the best matches. The filtering member divides the subject sequence into overlapping blocks, each block being sufficiently large to contain a minimum-length alignment from a known sequence. For each block, the filter member compares the block with every possible short fragment in the known sequences and determines a best match for each comparison. The determined set of short fragment best matches for the block provide an upper threshold on alignment values. Regions of a certain length from the known sequences that have a mean alignment value upper threshold greater than a target unit score are concatenated to form a union. The current block is compared to the union and provides an indication of best local alignment with the subject sequence.

  16. Method and apparatus for biological sequence comparison

    DOEpatents

    Marr, T.G.; Chang, W.I.

    1997-12-23

    A method and apparatus are disclosed for comparing biological sequences from a known source of sequences, with a subject (query) sequence. The apparatus takes as input a set of target similarity levels (such as evolutionary distances in units of PAM), and finds all fragments of known sequences that are similar to the subject sequence at each target similarity level, and are long enough to be statistically significant. The invention device filters out fragments from the known sequences that are too short, or have a lower average similarity to the subject sequence than is required by each target similarity level. The subject sequence is then compared only to the remaining known sequences to find the best matches. The filtering member divides the subject sequence into overlapping blocks, each block being sufficiently large to contain a minimum-length alignment from a known sequence. For each block, the filter member compares the block with every possible short fragment in the known sequences and determines a best match for each comparison. The determined set of short fragment best matches for the block provide an upper threshold on alignment values. Regions of a certain length from the known sequences that have a mean alignment value upper threshold greater than a target unit score are concatenated to form a union. The current block is compared to the union and provides an indication of best local alignment with the subject sequence. 5 figs.

  17. Comparison of modern icing cloud instruments

    NASA Technical Reports Server (NTRS)

    Takeuchi, D. M.; Jahnsen, L. J.; Callander, S. M.; Humbert, M. C.

    1983-01-01

    Intercomparison tests with Particle Measuring Systems (PMS) were conducted. Cloud liquid water content (LWC) measurements were also taken with a Johnson and Williams (JW) hot-wire device and an icing rate device (Leigh IDS). Tests include varying cloud LWC (0.5 to 5 au gm), cloud median volume diameter (MVD) (15 to 26 microns), temperature (-29 to 20 C), and air speeds (50 to 285 mph). Comparisons were based upon evaluating probe estimates of cloud LWC and median volume diameter for given tunnel settings. Variations of plus or minus 10% and plus or minus 5% in LWC and MVD, respectively, were determined of spray clouds between test made at given tunnel settings (fixed LWC, MVD, and air speed) indicating cloud conditions were highly reproducible. Although LWC measurements from JW and Leigh devices were consistent with tunnel values, individual probe measurements either consistently over or underestimated tunnel values by factors ranging from about 0.2 to 2. Range amounted to a factor of 6 differences between LWC estimates of probes for given cloud conditions. For given cloud conditions, estimates of cloud MVD between probes were within plus or minus 3 microns and 93% of the test cases. Measurements overestimated tunnel values in the range between 10 to 20 microns. The need for improving currently used calibration procedures was indicated. Establishment of test facility (or facilities) such as an icing tunnel where instruments can be calibrated against known cloud standards would be a logical choice.

  18. Comparison of Polar Cap (PC) index calculations.

    NASA Astrophysics Data System (ADS)

    Stauning, P.

    2012-04-01

    The Polar Cap (PC) index introduced by Troshichev and Andrezen (1985) is derived from polar magnetic variations and is mainly a measure of the intensity of the transpolar ionospheric currents. These currents relate to the polar cap antisunward ionospheric plasma convection driven by the dawn-dusk electric field, which in turn is generated by the interaction of the solar wind with the Earth's magnetosphere. Coefficients to calculate PCN and PCS index values from polar magnetic variations recorded at Thule and Vostok, respectively, have been derived by several different procedures in the past. The first published set of coefficients for Thule was derived by Vennerstrøm, 1991 and is still in use for calculations of PCN index values by DTU Space. Errors in the program used to calculate index values were corrected in 1999 and again in 2001. In 2005 DMI adopted a unified procedure proposed by Troshichev for calculations of the PCN index. Thus there exists 4 different series of PCN index values. Similarly, at AARI three different sets of coefficients have been used to calculate PCS indices in the past. The presentation discusses the principal differences between the various PC index procedures and provides comparisons between index values derived from the same magnetic data sets using the different procedures. Examples from published papers are examined to illustrate the differences.

  19. Comparison of bioseparation methods for microgravity experiments

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.; Cohly, Hari H. P.; Rodkey, L. Scott; Barlow, Grant H.; Hymer, Wesley C.

    1988-01-01

    The efficiency of the 1-g version of the continuous-flow electrophoresis (CFE) system flown on Space Shuttle missions is compared with the efficiency of a commercial CFE for separating living cells (human kidney, liver, and pituitary-gland cells and T-lymphocytes). In addition, the CFE system and a reciprocal isoelectric focusing (RIEF) system are compared with respect to protein pyrification efficiency. Correlations were made among electrophoretic mobilities (EPMs), secretory functions of cells, and input sample concentrations. A significant reduction in mean and range EPM was observed when input sample concentrations exceeded a low threshohold. This effect was not observed in microgravity experiments conducted at sample concentrations three times greater than the threshold for the controls. Comparison of CFE and RIEF methods showed that there are apparent advantages for each method depending on the product. For example, RIEF purification of urokinase removed more protein impurities, but focused the enzyme at a pH different than the enzyme's known isoelectric point.

  20. Comparison of IRST systems by SNR

    NASA Astrophysics Data System (ADS)

    Kim, Charles C.; Meyer, Ron

    2014-05-01

    Infrared (IR) cameras are widely used in systems to search and track. IR search and track (IRST) systems are most often available in one of two distinct spectral bands: mid-wave IR (MWIR) or long-wave IR (LWIR). Many have compared both systems in a number of ways. The comparison included field data and analysis under different scenarios. Yet, it is a challenge to make a right decision in choosing one band over the other band for a new scenario. In some respects, the attempt is like choosing between an apple and an orange. The signal-to-noise ratio (SNR) of a system for a point-like target is one criterion that helps one to make an informed decision. The formula for SNR commonly uses noise equivalent irradiance (NEI) that requires front optics. Such formalism cannot compare two bands before a camera is built complete with front optics. We derive a formula for SNR that utilizes noise equivalent differential temperature (NEDT) that does not require front optics. The formula is further simplified under some assumptions, which identifies critical parameters and provides an insight in comparing two bands. We have shown an example for a simple case.

  1. Distributed Wind Policy Comparison Tool Guidebook

    SciTech Connect

    Not Available

    2011-11-01

    Power through Policy: 'Best Practices' for Cost-Effective Distributed Wind is a U.S. Department of Energy (DOE)-funded project to identify distributed wind technology policy best practices and to help policymakers, utilities, advocates, and consumers examine their effectiveness using a pro forma model. Incorporating a customized feed from the Database of State Incentives for Renewables and Efficiency (DSIRE), the Web-based Distributed Wind Policy Comparison Tool (Policy Tool) is designed to assist state, local, and utility officials in understanding the financial impacts of different policy options to help reduce the cost of distributed wind technologies. The Policy Tool can be used to evaluate the ways that a variety of federal and state policies and incentives impact the economics of distributed wind (and subsequently its expected market growth). It also allows policymakers to determine the impact of policy options, addressing market challenges identified in the U.S. DOE's '20% Wind Energy by 2030' report and helping to meet COE targets.

  2. Comparison of Fiber Optic Strain Demodulation Implementations

    NASA Technical Reports Server (NTRS)

    Quach, Cuong C.; Vazquez, Sixto L.

    2005-01-01

    NASA Langley Research Center is developing instrumentation based upon principles of Optical Frequency-Domain Reflectometry (OFDR) for the provision of large-scale, dense distribution of strain sensors using fiber optics embedded with Bragg gratings. Fiber Optic Bragg Grating technology enables the distribution of thousands of sensors immune to moisture and electromagnetic interference with negligible weight penalty. At Langley, this technology provides a key component for research and development relevant to comprehensive aerospace vehicle structural health monitoring. A prototype system is under development that includes hardware and software necessary for the acquisition of data from an optical network and conversion of the data into strain measurements. This report documents the steps taken to verify the software that implements the algorithm for calculating the fiber strain. Brief descriptions of the strain measurement system and the test article are given. The scope of this report is the verification of software implementations as compared to a reference model. The algorithm will be detailed along with comparison results.

  3. Comparison of Ontology Reasoners: Racer, Pellet, Fact++

    NASA Astrophysics Data System (ADS)

    Huang, T.; Li, W.; Yang, C.

    2008-12-01

    In this paper, we examine some key aspects of three of the most popular and effective Semantic reasoning engines that have been developed: Pellet, RACER, and Fact++. While these reasonably advanced reasoners share some notable similarities, it is ultimately the creativity and unique nature of these reasoning engines that have resulted in the successes of each of these reasoners. Of the numerous dissimilarities, the most obvious example might be that while Pellet is written in Java, RACER employs the Lisp programming language and Fact++ was developed using C++. From this and many other distinctions in the system architecture, we can understand the benefits of each reasoner and potentially discover certain properties that may contribute to development of an optimal reasoner in the future. The objective of this paper is to establish a solid comparison of the reasoning engines based on their system architectures, features, and overall performances in real world application. In the end, we expect to produce a valid conclusion about the advantages and problems in each reasoner. While there may not be a decisive first place among the three reasoners, the evaluation will also provide some answers as to which of these current reasoning tools will be most effective in common, practical situations.

  4. Santa Barbara Cluster Comparison Test with DISPH

    NASA Astrophysics Data System (ADS)

    Saitoh, Takayuki R.; Makino, Junichiro

    2016-06-01

    The Santa Barbara cluster comparison project revealed that there is a systematic difference between entropy profiles of clusters of galaxies obtained by Eulerian mesh and Lagrangian smoothed particle hydrodynamics (SPH) codes: mesh codes gave a core with a constant entropy, whereas SPH codes did not. One possible reason for this difference is that mesh codes are not Galilean invariant. Another possible reason is the problem of the SPH method, which might give too much “protection” to cold clumps because of the unphysical surface tension induced at contact discontinuities. In this paper, we apply the density-independent formulation of SPH (DISPH), which can handle contact discontinuities accurately, to simulations of a cluster of galaxies and compare the results with those with the standard SPH. We obtained the entropy core when we adopt DISPH. The size of the core is, however, significantly smaller than those obtained with mesh simulations and is comparable to those obtained with quasi-Lagrangian schemes such as “moving mesh” and “mesh free” schemes. We conclude that both the standard SPH without artificial conductivity and Eulerian mesh codes have serious problems even with such an idealized simulation, while DISPH, SPH with artificial conductivity, and quasi-Lagrangian schemes have sufficient capability to deal with it.

  5. Comparison of Home Retrofit Programs in Wisconsin

    SciTech Connect

    Cunningham, K.; Hannigan, E.

    2013-03-01

    To explore ways to reduce customer barriers and increase home retrofit completions, several different existing home retrofit models have been implemented in the state of Wisconsin. This study compared these programs' performance in terms of savings per home and program cost per home to assess the relative cost-effectiveness of each program design. However, given the many variations in these different programs, it is difficult to establish a fair comparison based on only a small number of metrics. Therefore, the overall purpose of the study is to document these programs' performance in a case study approach to look at general patterns of these metrics and other variables within the context of each program. This information can be used by energy efficiency program administrators and implementers to inform home retrofit program design. Six different program designs offered in Wisconsin for single-family energy efficiency improvements were included in the study. For each program, the research team provided information about the programs' approach and goals, characteristics, achievements and performance. The program models were then compared with performance results -- program cost and energy savings -- to help understand the overall strengths and weaknesses or challenges of each model.

  6. Comparison of Home Retrofit Programs in Wisconsin

    SciTech Connect

    Cunningham, Kerrie; Hannigan, Eileen

    2013-03-01

    To explore ways to reduce customer barriers and increase home retrofit completions, several different existing home retrofit models have been implemented in the state of Wisconsin. This study compared these programs' performance in terms of savings per home and program cost per home to assess the relative cost-effectiveness of each program design. However, given the many variations in these different programs, it is difficult to establish a fair comparison based on only a small number of metrics. Therefore, the overall purpose of the study is to document these programs' performance in a case study approach to look at general patterns of these metrics and other variables within the context of each program. This information can be used by energy efficiency program administrators and implementers to inform home retrofit program design. Six different program designs offered in Wisconsin for single-family energy efficiency improvements were included in the study. For each program, the research team provided information about the programs' approach and goals, characteristics, achievements and performance. The program models were then compared with performance results-program cost and energy savings-to help understand the overall strengths and weaknesses or challenges of each model.

  7. Performance comparison of video quality metrics

    NASA Astrophysics Data System (ADS)

    Zoran, Kotevski; Pece, Mitrevski

    2010-02-01

    The development of digital video technology, due to its nature, introduced new approach to the objective video quality estimation. Basically there are two types of metrics for measuring the quality of digital video: purely mathematically defined video quality metrics (DELTA, MSAD, MSE, SNR and PSNR) where the error is mathematically calculated as a difference between the original and processed pixel, and video quality metrics that have similar characteristics as the Human Visual System (SSIM, NQI, VQM), where the perceptual quality is also considered in the overall quality estimation. The metrics from the first group are more technical ones and because the visual quality of perception is more complex than pixel error calculation, many examples show that their video quality estimation is deficiently accurate. The second group of metrics work in a different manner compared to previous, calculating the scene structure in the overall video quality estimation. This paper is concerned with experimental comparison of the performance of Structural Similarity (SSIM) and Video Quality Metric (VQM) metrics for objective video quality estimation. For the purpose of this experiment, more than 300 short video sequences were prepared. The measurements of these video sequences are used to draw the metrics dependence to common changes in processed video sequences. These changes include changes in: brightness, contrast, hue, saturation and noise. This paper pinpoints the key characteristics of each metric, gives the conclusion of the better performing one and gives directions for improvement of objective video quality estimation.

  8. Perceptual expertise in forensic facial image comparison

    PubMed Central

    White, David; Phillips, P. Jonathon; Hahn, Carina A.; Hill, Matthew; O'Toole, Alice J.

    2015-01-01

    Forensic facial identification examiners are required to match the identity of faces in images that vary substantially, owing to changes in viewing conditions and in a person's appearance. These identifications affect the course and outcome of criminal investigations and convictions. Despite calls for research on sources of human error in forensic examination, existing scientific knowledge of face matching accuracy is based, almost exclusively, on people without formal training. Here, we administered three challenging face matching tests to a group of forensic examiners with many years' experience of comparing face images for law enforcement and government agencies. Examiners outperformed untrained participants and computer algorithms, thereby providing the first evidence that these examiners are experts at this task. Notably, computationally fusing responses of multiple experts produced near-perfect performance. Results also revealed qualitative differences between expert and non-expert performance. First, examiners' superiority was greatest at longer exposure durations, suggestive of more entailed comparison in forensic examiners. Second, experts were less impaired by image inversion than non-expert students, contrasting with face memory studies that show larger face inversion effects in high performers. We conclude that expertise in matching identity across unfamiliar face images is supported by processes that differ qualitatively from those supporting memory for individual faces. PMID:26336174

  9. Comparison of Biomass Burning Smoke Plume Models

    NASA Astrophysics Data System (ADS)

    Carlson, L. J.; Mason, S. A.; Trentmann, J.; Winterrath, T.; Christian, T. J.; Yokelson, R. J.; Andreae, M. O.; Hobbs, P. V.

    2003-12-01

    Biomass burning is known to inject considerable quantities of trace gases into the atmosphere. Recent laboratory, field, and modeling studies have shown that significant atmospheric transformations occur within the vicinity of fire events before these emissions are released into the regional atmosphere. Understanding the local-scale transformations is an important parameter for inclusion into larger, global tropospheric models. An inter-model comparison was carried out between two independently developed zero-dimensional, gas-phase tropospheric models used to describe the photochemical evolution of young biomass burning smoke plumes. One of these models was developed and operated at the Max Planck Institute in Mainz, Germany; the second was constructed at the University of Montana- Missoula and is currently run at SUNY Fredonia. Identical initial parameters used in both models were taken from field measurements of biomass burning events under very different fire conditions (African savanna and Alaskan forest/shrub/bog mixture). The Fredonia model predicts slightly different chemistry than the Mainz model, which results in higher radical concentrations and lower PAN production when the same initial conditions are applied. Differences in the simulated results may be attributed to subtle differences in the calculation of photolytic rate constants and the modeled tropospheric chemistry. We survey the differences in model construction and the outcomes.

  10. Cephalometric comparison of cesarean and normal births

    PubMed Central

    Goymen, Merve; Topcuoglu, Tolga; Aktan, Ali Murat; Isman, Ozlem

    2016-01-01

    Objective: The aim of this study was to compare cephalometric variables of subjects with normal and cesarean births. Materials and Methods: Ninety age- and gender-matched patients, who were treated in Gaziantep University, Faculty of Dentistry Orthodontics Department were equally divided into normal and cesarean groups according to the birth methods reported by their mothers. To eliminate the negative effects of being different in terms of age and gender among parameters, control, and patient groups were matched in the present study. Pretreatment cephalometrics radiographs were used. Six measurements representing sagittal and vertical relationships were evaluated from pretreatment cephalograms using Dolphin Imaging Orthodontics Software was used in this issue by an orthodontist. Kolmogorov–Smirnov test, Student's t-test, and Mann–Whitney U-test were used for statistical comparisons. Results: A point-nasion-B point angle (ANB) and Wits values were higher in the normal group, while sella-nasion-A point angle, sella-nasion-B point angle, Frankfort horizontal-mandibular plane angle, and gonion-gnathion-SN plane angle values were higher in the cesarean group. However, the groups showed no significant differences (P > 0.05). ANB angle and Wits values showed high correlation. Conclusions: Within the study limitations, the results suggest that the birth method may not have a considerable effect on the development of the craniofacial skeletal system. PMID:27095896

  11. Valuing Science: A Turkish-American comparison

    NASA Astrophysics Data System (ADS)

    Titrek, Osman; Cobern, William W.

    2011-02-01

    The process of modernization began in Turkey under the reform government of Mustafa Kemal Ataturk (1881-1938). Turkey officially became a secular nation seeking to develop a modern economy with modern science and technology and political democracy. Turkey also has long been, and remains, a deeply religious society. Specifically, the practice of Islam is widespread, which raises the important question: whether the path of modernization in Turkey will look more like the American pattern or the European, where the Europeans are much more philosophically secular than the Americans? One way to look at this question is by examining how people value science vis-à-vis other important aspects of society and culture. Hence, our study is a comparative look at Turkish and American opinions about science. The American society, which is certainly a very modern society, is of particular interest in Turkey, given the significant religiosity of the American people, making the American and Turkish societies similar at least on this one significant point. Although we do not have comparable European data at this time, our Turkish-American comparison can be suggestive of whether or not Turkey is likely to follow the American pattern of a highly modernized yet deeply religious society.

  12. Comparison and optimization of ancient DNA extraction.

    PubMed

    Rohland, Nadin; Hofreiter, Michael

    2007-03-01

    Ancient DNA analyses rely on the extraction of the tiny amounts of DNA remaining in samples that are hundreds to tens of thousands of years old. Despite the critical role extraction efficiency plays in this field of research, no study has comprehensively compared ancient DNA extraction techniques to date. There are a wide range of methods currently in use, which rely on such disparate principles as spin columns, alcohol precipitation, or binding to silica. We have compared a number of these methods using quantitative PCR and then optimized each step of the most promising method. We found that most chemicals routinely added to ancient DNA extraction buffers do not increase, and sometimes even decrease, DNA yields. Consequently, our optimized method uses a buffer consisting solely of EDTA and proteinase K for bone digestion and binding DNA to silica via guanidinium thiocyanate for DNA purification. In a comparison with published methods, this minimalist approach, on average, outperforms all other methods in terms of DNA yields as measured using quantitative PCR. We also found that the addition of bovine serum albumin (BSA) to the PCR helps to overcome inhibitors in ancient DNA extracts. Finally, we observed a marked difference in the performance between different types of DNA polymerases, as measured by amplification success.

  13. Models comparison for JET polarimeter data

    SciTech Connect

    Mazzotta, C.; Orsitto, F. P.; Giovannozzi, E.; Boboc, A.; Tudisco, O.; Zabeo, L.; Brombin, M.; Murari, A.

    2008-03-12

    A complete comparison between the theory and the measurements in polarimetry was done by using the Far Infrared Polarimeter at JET. More than 300 shots were analyzed, including a wide spectrum of JET scenarios in all critical conditions for polarimetry: high density, high and very low fields, high temperatures.This work is aimed at the demonstration of the robustness of the theoretical models for the JET polarimeter measurements in the perspective of using these models for ITER like plasma scenarios . In this context, an assessment was performed on how the line-integrated plasma density along the central vertical chord of FIR polarimeter could be evaluated using the Cotton-Mouton effect and its possible concrete use to correct fringe jumps of the interferometer.The models considered are: i) the rigorous numerical solution of the Stokes propagation equations, using dielectric tensor evaluated from JET equilibrium and Thomson scattering [1,2]; ii) two types of approximated solutions [2,3] and iii) the Guenther empirical model [4] that considers the mutual effect between Cotton-Mouton and Faraday rotation angle. The model calculations have been compared with polarimeter measurements for the Cotton-Mouton phase shift.The agreement with theory is satisfactory within the limits of experimental errors [3].

  14. jTracker and Monte Carlo Comparison

    NASA Astrophysics Data System (ADS)

    Selensky, Lauren; SeaQuest/E906 Collaboration

    2015-10-01

    SeaQuest is designed to observe the characteristics and behavior of `sea-quarks' in a proton by reconstructing them from the subatomic particles produced in a collision. The 120 GeV beam from the main injector collides with a fixed target and then passes through a series of detectors which records information about the particles produced in the collision. However, this data becomes meaningful only after it has been processed, stored, analyzed, and interpreted. Several programs are involved in this process. jTracker (sqerp) reads wire or hodoscope hits and reconstructs the tracks of potential dimuon pairs from a run, and Geant4 Monte Carlo simulates dimuon production and background noise from the beam. During track reconstruction, an event must meet the criteria set by the tracker to be considered a viable dimuon pair; this ensures that relevant data is retained. As a check, a comparison between a new version of jTracker and Monte Carlo was made in order to see how accurately jTracker could reconstruct the events created by Monte Carlo. In this presentation, the results of the inquest and their potential effects on the programming will be shown. This work is supported by U.S. DOE MENP Grant DE-FG02-03ER41243.

  15. Comparison between electroglottography and electromagnetic glottography

    SciTech Connect

    Titze, Ingo R.; Story, Brad H.; Burnett, Gregory C.; Holzrichter, John F.; Ng, Lawrence C.; Lea, Wayne A.

    2000-01-01

    Newly developed glottographic sensors, utilizing high-frequency propagating electromagnetic waves, were compared to a well-established electroglottographic device. The comparison was made on four male subjects under different phonation conditions, including three levels of vocal fold adduction (normal, breathy, and pressed), three different registers (falsetto, chest, and fry), and two different pitches. Agreement between the sensors was always found for the glottal closure event, but for the general wave shape the agreement was better for falsetto and breathy voice than for pressed voice and vocal fry. Differences are attributed to the field patterns of the devices. Whereas the electroglottographic device can operate only in a conduction mode, the electromagnetic device can operate in either the forward scattering (diffraction) mode or in the backward scattering (reflection) mode. Results of our tests favor the diffraction mode because a more favorable angle imposed on receiving the scattered (reflected) signal did not improve the signal strength. Several observations are made on the uses of the electromagnetic sensors for operation without skin contact and possibly in an array configuration for improved spatial resolution within the glottis. (c) 2000 Acoustical Society of America.

  16. A Comparison of Simulation Capabilities for Ducts

    SciTech Connect

    Miller, William A.; Smith, Matt K.; Gu, Lixing; New, Joshua Ryan

    2014-11-01

    Typically, the cheapest way to install a central air conditioning system in residential buildings is to place the ductwork in the attic. Energy losses due to duct-attic interactions can be great, but current whole-house models are unable to capture the dynamic multi-mode physics of the interactions. The building industry is notoriously fragmented and unable to devote adequate research resources to solve this problem. Builders are going to continue to put ducts in the attic because floor space is too expensive to closet them within living space, and there are both construction and aesthetic issues with other approaches such as dropped ceilings. Thus, there is a substantial need to publicly document duct losses and the cost of energy used by ducts in attics so that practitioners, builders, homeowners and state and federal code officials can make informed decisions leading to changes in new construction and additional retrofit actions. Thus, the goal of this study is to conduct a comparison of AtticSim and EnergyPlus simulation algorithms to identify specific features for potential inclusion in EnergyPlus that would allow higher-fidelity modeling of HVAC operation and duct transport of conditioned air. It is anticipated that the resulting analysis from these simulation tools will inform energy decisions relating to the role of ducts in future building energy codes and standards.

  17. The National Ballistics Imaging Comparison (NBIC) project.

    PubMed

    Song, J; Vorburger, T V; Ballou, S; Thompson, R M; Yen, J; Renegar, T B; Zheng, A; Silver, R M; Ols, M

    2012-03-10

    In response to the guidelines issued by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB-International) to establish traceability and quality assurance in U.S. crime laboratories, a NIST/ATF joint project entitled National Ballistics Imaging Comparison (NBIC) was initialized in 2008. The NBIC project aims to establish a National Traceability and Quality System for ballistics identifications in crime laboratories within the National Integrated Ballistics Information Network (NIBIN) of the U.S. NIST Standard Reference Material (SRM) 2460 bullets and 2461 cartridge cases are used as reference standards. 19 ballistics examiners from 13 U.S. crime laboratories participated in this project. They each performed 24 periodic image acquisitions and correlations of the SRM bullets and cartridge cases over the course of a year, but one examiner only participated in Phase 1 tests of SRM cartridge case. The correlation scores were collected by NIST for statistical analyses, from which control charts and control limits were developed for the proposed Quality System and for promoting future assessments and accreditations for firearm evidence in U.S. forensic laboratories in accordance with the ISO 17025 Standard.

  18. Comparisons of some large scientific computers

    NASA Technical Reports Server (NTRS)

    Credeur, K. R.

    1981-01-01

    In 1975, the National Aeronautics and Space Administration (NASA) began studies to assess the technical and economic feasibility of developing a computer having sustained computational speed of one billion floating point operations per second and a working memory of at least 240 million words. Such a powerful computer would allow computational aerodynamics to play a major role in aeronautical design and advanced fluid dynamics research. Based on favorable results from these studies, NASA proceeded with developmental plans. The computer was named the Numerical Aerodynamic Simulator (NAS). To help insure that the estimated cost, schedule, and technical scope were realistic, a brief study was made of past large scientific computers. Large discrepancies between inception and operation in scope, cost, or schedule were studied so that they could be minimized with NASA's proposed new compter. The main computers studied were the ILLIAC IV, STAR 100, Parallel Element Processor Ensemble (PEPE), and Shuttle Mission Simulator (SMS) computer. Comparison data on memory and speed were also obtained on the IBM 650, 704, 7090, 360-50, 360-67, 360-91, and 370-195; the CDC 6400, 6600, 7600, CYBER 203, and CYBER 205; CRAY 1; and the Advanced Scientific Computer (ASC). A few lessons learned conclude the report.

  19. Comparison of Different Commercial Wireless Keypad Systems

    NASA Astrophysics Data System (ADS)

    Burnstein, Ray A.; Lederman, Leon M.

    2003-05-01

    Wireless keypad systems have been in limited use for the past 10 years in the classroom.1,2 Such systems can be used to quiz students in real time during the class, thus engaging students more directly in the lecture.3 Nonetheless, until recently widespread use of such keypad systems has been limited for several reasons. First, the original systems were relatively expensive but perhaps more important was the reluctance on the part of faculty to change the existing passive lecture format.4,5 However, problems associated with large lecture classes6 and the validation of the concept of "interactive engagement" from the high-statistics study of Hake7 has changed the opinions of many. In addition the desirability of peer learning,8 which is enhanced with a response system, has also been accepted. At the present time a number of commercial systems are available. The purpose of this paper is to present a comparison and summary of what is commercially available9 and a reminder that keypads are a dramatically effective teaching and learning tool.

  20. A numerical comparison of sensitivity analysis techniques

    SciTech Connect

    Hamby, D.M.

    1993-12-31

    Engineering and scientific phenomena are often studied with the aid of mathematical models designed to simulate complex physical processes. In the nuclear industry, modeling the movement and consequence of radioactive pollutants is extremely important for environmental protection and facility control. One of the steps in model development is the determination of the parameters most influential on model results. A {open_quotes}sensitivity analysis{close_quotes} of these parameters is not only critical to model validation but also serves to guide future research. A previous manuscript (Hamby) detailed many of the available methods for conducting sensitivity analyses. The current paper is a comparative assessment of several methods for estimating relative parameter sensitivity. Method practicality is based on calculational ease and usefulness of the results. It is the intent of this report to demonstrate calculational rigor and to compare parameter sensitivity rankings resulting from various sensitivity analysis techniques. An atmospheric tritium dosimetry model (Hamby) is used here as an example, but the techniques described can be applied to many different modeling problems. Other investigators (Rose; Dalrymple and Broyd) present comparisons of sensitivity analyses methodologies, but none as comprehensive as the current work.

  1. Protein sequence comparison and protein evolution

    SciTech Connect

    Pearson, W.R.

    1995-12-31

    This tutorial was one of eight tutorials selected to be presented at the Third International Conference on Intelligent Systems for Molecular Biology which was held in the United Kingdom from July 16 to 19, 1995. This tutorial examines how the information conserved during the evolution of a protein molecule can be used to infer reliably homology, and thus a shared proteinfold and possibly a shared active site or function. The authors start by reviewing a geological/evolutionary time scale. Next they look at the evolution of several protein families. During the tutorial, these families will be used to demonstrate that homologous protein ancestry can be inferred with confidence. They also examine different modes of protein evolution and consider some hypotheses that have been presented to explain the very earliest events in protein evolution. The next part of the tutorial will examine the technical aspects of protein sequence comparison. Both optimal and heuristic algorithms and their associated parameters that are used to characterize protein sequence similarities are discussed. Perhaps more importantly, they survey the statistics of local similarity scores, and how these statistics can both be used to improve the selectivity of a search and to evaluate the significance of a match. They them examine distantly related members of three protein families, the serine proteases, the glutathione transferases, and the G-protein-coupled receptors (GCRs). Finally, the discuss how sequence similarity can be used to examine internal repeated or mosaic structures in proteins.

  2. Alignment-free protein interaction network comparison

    PubMed Central

    Ali, Waqar; Rito, Tiago; Reinert, Gesine; Sun, Fengzhu; Deane, Charlotte M.

    2014-01-01

    Motivation: Biological network comparison software largely relies on the concept of alignment where close matches between the nodes of two or more networks are sought. These node matches are based on sequence similarity and/or interaction patterns. However, because of the incomplete and error-prone datasets currently available, such methods have had limited success. Moreover, the results of network alignment are in general not amenable for distance-based evolutionary analysis of sets of networks. In this article, we describe Netdis, a topology-based distance measure between networks, which offers the possibility of network phylogeny reconstruction. Results: We first demonstrate that Netdis is able to correctly separate different random graph model types independent of network size and density. The biological applicability of the method is then shown by its ability to build the correct phylogenetic tree of species based solely on the topology of current protein interaction networks. Our results provide new evidence that the topology of protein interaction networks contains information about evolutionary processes, despite the lack of conservation of individual interactions. As Netdis is applicable to all networks because of its speed and simplicity, we apply it to a large collection of biological and non-biological networks where it clusters diverse networks by type. Availability and implementation: The source code of the program is freely available at http://www.stats.ox.ac.uk/research/proteins/resources. Contact: w.ali@stats.ox.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25161230

  3. Perceptual expertise in forensic facial image comparison.

    PubMed

    White, David; Phillips, P Jonathon; Hahn, Carina A; Hill, Matthew; O'Toole, Alice J

    2015-09-01

    Forensic facial identification examiners are required to match the identity of faces in images that vary substantially, owing to changes in viewing conditions and in a person's appearance. These identifications affect the course and outcome of criminal investigations and convictions. Despite calls for research on sources of human error in forensic examination, existing scientific knowledge of face matching accuracy is based, almost exclusively, on people without formal training. Here, we administered three challenging face matching tests to a group of forensic examiners with many years' experience of comparing face images for law enforcement and government agencies. Examiners outperformed untrained participants and computer algorithms, thereby providing the first evidence that these examiners are experts at this task. Notably, computationally fusing responses of multiple experts produced near-perfect performance. Results also revealed qualitative differences between expert and non-expert performance. First, examiners' superiority was greatest at longer exposure durations, suggestive of more entailed comparison in forensic examiners. Second, experts were less impaired by image inversion than non-expert students, contrasting with face memory studies that show larger face inversion effects in high performers. We conclude that expertise in matching identity across unfamiliar face images is supported by processes that differ qualitatively from those supporting memory for individual faces.

  4. Comparison of hyperspectral change detection algorithms

    NASA Astrophysics Data System (ADS)

    Pieper, M.; Manolakis, D.; Truslow, E.; Cooley, T.; Brueggeman, M.; Weisner, A.; Jacobson, J.

    2015-09-01

    There are a multitude of civilian and military applications for the detection of anomalous changes in hyper-spectral images. Anomalous changes occur when the material within a pixel is replaced. Environmental factors that change over time, such as illumination, will affect the radiance of all the pixels in a scene, despite the materials within remaining constant. The goal of an anomalous change detection algorithm is to suppress changes caused by the environment, and detect pixels where the materials within have changed. Anomalous change detection is a two step process. Two co-registered images of a scene are first transformed to maximize the overall correlation between the images, then an anomalous change detector (ACD) is applied to the transformed images. The transforms maximize the correlation between the two images to attenuate the environmental differences that distract from the anomalous changes of importance. Several categories of transforms with different optimization parameters are discussed and compared. One of two types of ACDs are then applied to the transformed images. The first ACD uses the difference of the two transformed images. The second concatenates the spectra of two images and uses an aggregated ACD. A comparison of the two ACD methods and their effectiveness with the different transforms is done for the first time.

  5. The Scylla Multi-Code Comparison Project

    NASA Astrophysics Data System (ADS)

    Maller, Ariyeh; Stewart, Kyle; Bullock, James; Oñorbe, Jose; Scylla Team

    2016-01-01

    Cosmological hydrodynamical simulations are one of the main techniques used to understand galaxy formation and evolution. However, it is far from clear to what extent different numerical techniques and different implementations of feedback yield different results. The Scylla Multi-Code Comparison Project seeks to address this issue by running idenitical initial condition simulations with different popular hydrodynamic galaxy formation codes. Here we compare simulations of a Milky Way mass halo using the codes enzo, ramses, art, arepo and gizmo-psph. The different runs produce galaxies with a variety of properties. There are many differences, but also many similarities. For example we find that in all runs cold flow disks exist; extended gas structures, far beyond the galactic disk, that show signs of rotation. Also, the angular momentum of warm gas in the halo is much larger than the angular momentum of the dark matter. We also find notable differences between runs. The temperature and density distribution of hot gas can differ by over an order of magnitude between codes and the stellar mass to halo mass relation also varies widely. These results suggest that observations of galaxy gas halos and the stellar mass to halo mass relation can be used to constarin the correct model of feedback.

  6. Orion Landing Simulation Eight Soil Model Comparison

    NASA Technical Reports Server (NTRS)

    Mark, Stephen D.

    2009-01-01

    LS-DYNA finite element simulations of a rigid Orion Crew Module (CM) were used to investigate the CM impact behavior on eight different soil models. Ten different landing conditions, characterized by the combination of CM vertical and horizontal velocity, hang angle, and roll angle were simulated on the eight different soils. The CM center of gravity accelerations, pitch angle, kinetic energy, and soil contact forces were the outputs of interest. The simulation results are presented, with comparisons of the CM behavior on the different soils. The soils analyzed in this study can be roughly categorized as soft, medium, or hard, according to the CM accelerations that occur when landing on them. The soft group is comprised of the Carson Sink Wet soil and the Kennedy Space Center (KSC) Low Density Dry Sand. The medium group includes Carson Sink Dry, the KSC High Density In-Situ Moisture Sand and High Density Flooded Sand, and Cuddeback B. The hard soils are Cuddeback A and the Gantry Unwashed Sand. The softer soils were found to produce lower peak accelerations, have more stable pitch behavior, and to be less sensitive to the landing conditions. This investigation found that the Cuddeback A soil produced the highest peak accelerations and worst stability conditions, and that the best landing performance was achieved on the KSC Low Density Dry Sand.

  7. Comparison of surface and satellite gravity data

    NASA Technical Reports Server (NTRS)

    Rapp, R. H.

    1978-01-01

    Satellite derived potential coefficients (GEM 9) are compared to terrestrial gravity data by degree in terms of coefficient differences and in terms of mean anomaly differences. The root mean square undulation difference (to degree 20) was 9 + or - m and the anomaly difference was + or - 7 mgals with GEM 9 commission errors of + or - 1.7 m and + or - 3.8 mgals. The standard deviations of the GEM 9 implied undulations increased from + or - 4 cm at degree 2 to + or - 53 cm at degree 20. The corresponding values implied by a recent (June 1978) terrestrial 5 deg field were + or - 2.53 m and + or - 0.38 m (at degree 20). Comparisons between Geos-3 altimeter derived anomalies and 1 deg X 1 Deg terrestrial data showed that + or - 6-8 mgals is a reasonable accuracy estimate for the altimeter derived anomalies. Anomalies derived from satellite to satellite tracking data indicate an accuracy of about + or - 6 mgals for the recovery of 5 deg equal area blocks.

  8. Programming Tools: Status, Evaluation, and Comparison

    NASA Technical Reports Server (NTRS)

    Cheng, Doreen Y.; Cooper, D. M. (Technical Monitor)

    1994-01-01

    In this tutorial I will first describe the characteristics of scientific applications and their developers, and describe the computing environment in a typical high-performance computing center. I will define the user requirements for tools that support application portability and present the difficulties to satisfy them. These form the basis of the evaluation and comparison of the tools. I will then describe the tools available in the market and the tools available in the public domain. Specifically, I will describe the tools for converting sequential programs, tools for developing portable new programs, tools for debugging and performance tuning, tools for partitioning and mapping, and tools for managing network of resources. I will introduce the main goals and approaches of the tools, and show main features of a few tools in each category. Meanwhile, I will compare tool usability for real-world application development and compare their different technological approaches. Finally, I will indicate the future directions of the tools in each category.

  9. Comparison of computed tomography dose reporting software.

    PubMed

    Abdullah, A; Sun, Z; Pongnapang, N; Ng, K-H

    2012-08-01

    Computed tomography (CT) dose reporting software facilitates the estimation of doses to patients undergoing CT examinations. In this study, comparison of three software packages, i.e. CT-Expo (version 1.5, Medizinische Hochschule, Hannover, Germany), ImPACT CT Patients Dosimetry Calculator (version 0.99×, Imaging Performance Assessment on Computed Tomography, www.impactscan.org) and WinDose (version 2.1a, Wellhofer Dosimetry, Schwarzenbruck, Germany), has been made in terms of their calculation algorithm and the results of calculated doses. Estimations were performed for head, chest, abdominal and pelvic examinations based on the protocols recommended by European guidelines using single-slice CT (SSCT) (Siemens Somatom Plus 4, Erlangen, Germany) and multi-slice CT (MSCT) (Siemens Sensation 16, Erlangen, Germany) for software-based female and male phantoms. The results showed that there are some differences in final dose reporting provided by these software packages. There are deviations of effective doses produced by these software packages. Percentages of coefficient of variance range from 3.3 to 23.4 % in SSCT and from 10.6 to 43.8 % in MSCT. It is important that researchers state the name of the software that is used to estimate the various CT dose quantities. Users must also understand the equivalent terminologies between the information obtained from the CT console and the software packages in order to use the software correctly.

  10. The National Ballistics Imaging Comparison (NBIC) project.

    PubMed

    Song, J; Vorburger, T V; Ballou, S; Thompson, R M; Yen, J; Renegar, T B; Zheng, A; Silver, R M; Ols, M

    2012-03-10

    In response to the guidelines issued by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB-International) to establish traceability and quality assurance in U.S. crime laboratories, a NIST/ATF joint project entitled National Ballistics Imaging Comparison (NBIC) was initialized in 2008. The NBIC project aims to establish a National Traceability and Quality System for ballistics identifications in crime laboratories within the National Integrated Ballistics Information Network (NIBIN) of the U.S. NIST Standard Reference Material (SRM) 2460 bullets and 2461 cartridge cases are used as reference standards. 19 ballistics examiners from 13 U.S. crime laboratories participated in this project. They each performed 24 periodic image acquisitions and correlations of the SRM bullets and cartridge cases over the course of a year, but one examiner only participated in Phase 1 tests of SRM cartridge case. The correlation scores were collected by NIST for statistical analyses, from which control charts and control limits were developed for the proposed Quality System and for promoting future assessments and accreditations for firearm evidence in U.S. forensic laboratories in accordance with the ISO 17025 Standard. PMID:22014973

  11. 77 FR 39236 - Nanomaterial Case Study: A Comparison of Multiwalled Carbon Nanotubes and Decabromodiphenyl Ether...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... AGENCY Nanomaterial Case Study: A Comparison of Multiwalled Carbon Nanotubes and Decabromodiphenyl Ether... Study: A Comparison of Multiwalled Carbon Nanotubes and Decabromodiphenyl Ether Flame-Retardant Coatings... ``Nanomaterial Case Study: A Comparison of Multiwalled Carbon Nanotubes and Decabromodiphenyl Ether...

  12. KEY COMPARISON: Final report on key comparison CCQM-K30: Determination of lead in wine

    NASA Astrophysics Data System (ADS)

    Hearn, Ruth; Santamaria-Fernandez, Rebeca; Sargent, Mike

    2008-01-01

    The CCQM-K30 key comparison was organized by the Inorganic Analysis Working Group (IAWG) of the CCQM to test the capabilities of national metrological institutes (NMIs) to measure the lead content of wine at the ~3 ng/g level. LGC designed and coordinated the study with the samples being prepared and distributed by Fundacion Chile. Eleven NMIs participated in the key comparison, nine of whom used isotope dilution, one used ICP-MS with external calibration and another used GF-AAS with external calibration. The two laboratories who did not use IDMS, subsequently reported technical difficulties and were therefore not used in the calculation of the KCRV. The agreement among the laboratories using IDMS was excellent as evidenced by the small values for both the equivalence statements (Di < 0.2 ng/g) and the associated uncertainties (ui < 0.3 ng/g). A pilot study (P12.1) was performed concurrently with the same sample used in CCQM-K30 by laboratories preferring to participate in the pilot study. The pilot study also included the additional analytes: iron, copper and cadmium. The results of the pilot study are reported separately. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  13. Quantum private comparison with a malicious third party

    NASA Astrophysics Data System (ADS)

    Sun, Zhiwei; Yu, Jianping; Wang, Ping; Xu, Lingling; Wu, Chunhui

    2015-06-01

    In this paper, we will show that quantum private comparison protocol is secure when a malicious third party is presented. The security of the protocol is considered in a cheat-sensitive model, in which the TP is kept honest by the possibility of being caught cheating. Besides, we enhance the privacy of the quantum private comparison protocol, where the participants' inputs and the comparison result can be preserved. Furthermore, in contrast to pervious protocols requiring a large amount of quantum resources, such as entanglement and quantum memory, our protocol is based on BB84 protocol, which is more feasible for practical applications. Finally, we analyze the security of the presented protocol.

  14. SRTM Radar - Landsat Image Comparison, Patagonia, Argentina

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In addition to an elevation model of most of Earth'slandmass, the Shuttle Radar Topography Mission will produce C-band radar imagery of the same area. This imagery is essentially a 10-day snapshot view of the Earth, as observed with 5.8 centimeter wavelength radar signals that were transmitted from the Shuttle, reflected by the Earth, and then recorded on the Shuttle. This six-image mosaic shows two examples of SRTM radar images (center) with comparisons to images acquired by the Landsat 7 satellite in the visible wavelengths (left) and an infrared wavelength (right). Both sets of images show lava flows in northern Patagonia, Argentina. In each case, the lava flows are relatively young compared to the surrounding rock formations.

    In visible light (left) image brightness corresponds to mineral chemistry and -- as expected -- both lava flows appear dark. Generally, the upper flow sits atop much lighter bedrock, providing good contrast and making the edges of the flow distinct. However, the lower flow borders some rocks that are similarly dark, and the flow boundaries are somewhat obscured. Meanwhile, in the radar images (center), image brightness corresponds to surface roughness (and topographic orientation) and substantial differences between the flows are visible. Much of the top flow appears dark, meaning it is fairly smooth. Consequently, it forms little or no contrast with the smooth and dark surrounding bedrock and thus virtually vanishes from view. However, the lower flow appears rough and bright and mostly forms good contrast with adjacent bedrock such that the flow is locally more distinct here than in the visible Landsat view. For further comparison, infrared Landsat images (right) again show image brightnesses related to mineral chemistry, but the lava flows appear lighter than in the visible wavelengths. Consequently, the lower lava flow becomes fairly obscure among the various surrounding rocks, just as the upper flow did in the radar image. The

  15. GCSS Cirrus Parcel Model Comparison Project

    NASA Technical Reports Server (NTRS)

    Lin, Ruei-Fong; Starr, David OC.; DeMott, Paul J.; Cotton, Richard; Jensen, Eric; Sassen, Kenneth; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The Cirrus Parcel Model Comparison Project, a project of GCSS Working Group on Cirrus Cloud Systems (WG2), involves the systematic comparison of current models of ice crystal nucleation and growth for specified, typical, cirrus cloud environments. The goal of this project is to document and understand the factors resulting in significant inter-model differences. The intent is to foment research leading to model improvement and validation. In Phase 1 of the project reported here, simulated cirrus cloud microphysical properties are compared for situations of "warm" (-40 C) and "cold" (-60 C) cirrus subject to updrafts of 4, 20 and 100 cm/s, respectively. Five models participated. These models employ explicit microphysical schemes wherein the size distribution of each class of particles (aerosols and ice crystals) is resolved into bins. Simulations are made including both homogeneous and heterogeneous ice nucleation mechanisms. A single initial aerosol population of sulfuric acid particles is prescribed for all simulations. To isolate the treatment of the homogeneous freezing (of haze drops) nucleation process, the heterogeneous nucleation mechanism is disabled for a second parallel set of simulations. Qualitative agreement is found for the homogeneous-nucleation-only simulations, e.g., the number density of nucleated ice crystals increases with the strength of the prescribed updraft. However, non-negligible quantitative differences are found. Detailed analysis reveals that the homogeneous nucleation formulation, aerosol size, ice crystal growth rate (particularly the deposition coefficient), and water vapor uptake rate are critical components that lead to differences in predicted microphysics. Systematic bias exists between results based on a modified classical theory approach and models using an effective freezing temperature approach to the treatment of nucleation. Each approach is constrained by critical freezing data from laboratory studies, but each includes

  16. ENCORE: Software for Quantitative Ensemble Comparison.

    PubMed

    Tiberti, Matteo; Papaleo, Elena; Bengtsen, Tone; Boomsma, Wouter; Lindorff-Larsen, Kresten

    2015-10-01

    There is increasing evidence that protein dynamics and conformational changes can play an important role in modulating biological function. As a result, experimental and computational methods are being developed, often synergistically, to study the dynamical heterogeneity of a protein or other macromolecules in solution. Thus, methods such as molecular dynamics simulations or ensemble refinement approaches have provided conformational ensembles that can be used to understand protein function and biophysics. These developments have in turn created a need for algorithms and software that can be used to compare structural ensembles in the same way as the root-mean-square-deviation is often used to compare static structures. Although a few such approaches have been proposed, these can be difficult to implement efficiently, hindering a broader applications and further developments. Here, we present an easily accessible software toolkit, called ENCORE, which can be used to compare conformational ensembles generated either from simulations alone or synergistically with experiments. ENCORE implements three previously described methods for ensemble comparison, that each can be used to quantify the similarity between conformational ensembles by estimating the overlap between the probability distributions that underlie them. We demonstrate the kinds of insights that can be obtained by providing examples of three typical use-cases: comparing ensembles generated with different molecular force fields, assessing convergence in molecular simulations, and calculating differences and similarities in structural ensembles refined with various sources of experimental data. We also demonstrate efficient computational scaling for typical analyses, and robustness against both the size and sampling of the ensembles. ENCORE is freely available and extendable, integrates with the established MDAnalysis software package, reads ensemble data in many common formats, and can work with large

  17. ENCORE: Software for Quantitative Ensemble Comparison

    PubMed Central

    Tiberti, Matteo; Papaleo, Elena; Bengtsen, Tone; Boomsma, Wouter; Lindorff-Larsen, Kresten

    2015-01-01

    There is increasing evidence that protein dynamics and conformational changes can play an important role in modulating biological function. As a result, experimental and computational methods are being developed, often synergistically, to study the dynamical heterogeneity of a protein or other macromolecules in solution. Thus, methods such as molecular dynamics simulations or ensemble refinement approaches have provided conformational ensembles that can be used to understand protein function and biophysics. These developments have in turn created a need for algorithms and software that can be used to compare structural ensembles in the same way as the root-mean-square-deviation is often used to compare static structures. Although a few such approaches have been proposed, these can be difficult to implement efficiently, hindering a broader applications and further developments. Here, we present an easily accessible software toolkit, called ENCORE, which can be used to compare conformational ensembles generated either from simulations alone or synergistically with experiments. ENCORE implements three previously described methods for ensemble comparison, that each can be used to quantify the similarity between conformational ensembles by estimating the overlap between the probability distributions that underlie them. We demonstrate the kinds of insights that can be obtained by providing examples of three typical use-cases: comparing ensembles generated with different molecular force fields, assessing convergence in molecular simulations, and calculating differences and similarities in structural ensembles refined with various sources of experimental data. We also demonstrate efficient computational scaling for typical analyses, and robustness against both the size and sampling of the ensembles. ENCORE is freely available and extendable, integrates with the established MDAnalysis software package, reads ensemble data in many common formats, and can work with large

  18. Cross-Cultural Comparison of Maternal Sleep

    PubMed Central

    Mindell, Jodi A.; Sadeh, Avi; Kwon, Robert; Goh, Daniel Y. T.

    2013-01-01

    Background: To characterize cross-cultural sleep patterns and sleep problems in a large sample of mothers of children (ages birth to 6 years) in multiple predominantly Asian and predominantly Caucasian countries. Methods: Mothers of 10,085 young children (predominantly Asian countries/regions: China, Hong Kong, India, Korea, Japan, Malaysia, Philippines, Singapore, Thailand; predominantly Caucasian countries: Australia, Canada, New Zealand, United Kingdom, United States) completed an internet-based expanded version of the Pittsburgh Sleep Quality Index. Results: Mothers in predominantly Asian countries/regions had later bedtimes, decreased number and duration of night wakings, more nighttime sleep, and more total sleep than mothers from predominantly Caucasian countries, P < 0.001. More than half (54.7%) of mothers reported having poor sleep, ranging from 50.9% of mothers in Malaysia to 77.8% of mothers in Japan. Sleep disturbance symptoms were quite common, especially symptoms related to insomnia, and were more likely to be reported by mothers in predominantly Caucasian countries. However, psychosocial factors, including having children of a younger age, being unemployed, and having a lower education level were the best predictors of poor sleep, whereas culture was not a significant predictor. Conclusions: Overall, mothers in predominantly Asian countries/regions reported later bedtimes but sleeping better and longer than mothers from predominantly Caucasian countries, which is dissimilar to cross-cultural findings of young children. Psychosocial factors were found to be the best predictors of poor sleep, irrespective of culture. Further studies are needed to understand the impact of these findings. Citation: Mindell JA; Sadeh A; Kwon R; Goh DYT. Cross-cultural comparison of maternal sleep. SLEEP 2013;36(11):1699-1706. PMID:24179304

  19. Comparison of AMZIRC and GRCop-84

    NASA Technical Reports Server (NTRS)

    de Groh, Henry C. III; Ellis, David; Loewenthal, William

    2006-01-01

    The mechanical properties of two copper alloys with high thermal conductivity, GRCop-84 and AMZIRC, were compared. These are competing alloys in high temperature, high heat flux applications such as rocket nozzles. The GRCop-84 data presented was taken from previous work. The results of new tensile, creep, and compression tests on AMZIRC are presented. Tests were done on as-received hard drawn material, and on material that had been subjected to a heat treatment designed to simulate a brazing operation at 935 C. As-received AMZIRC was found to have excellent properties at temperatures below 550 C, with room temperature yield and ultimate tensile strengths of about 500 MPa, and ductile failures. By comparison, GRCop-84 s room temperature tensile yield and ultimate strengths are about 200 and 380 MPa respectively. However, the simulated brazing heat treatment substantially decreased the mechanical properties of AMZIRC; and the strength of as-received AMZIRC dropped precipitously as test temperatures exceeded 500 C. The properties of GRCop-84 were not significantly affected by the 935 C heat treatment. As a result, there appear to be advantages to GRCop- 84 over AMZIRC if use or processing temperatures of greater than 500 C are expected. Tensile creep tests were done at 500 and 650 C. At these temperatures, the creep properties of GRCop-84 were superior to AMZIRC s. At equivalent rupture life and stress, GRCop-84 was found to have a 150 C temperature advantage over AMZIRC; for equivalent rupture life and temperature GRCop-84 was two times stronger.

  20. Second-generation central receiver technology comparison

    NASA Astrophysics Data System (ADS)

    Klimas, P. C.; Becker, M.

    Fifteen years of solar thermal technology development have produced a considerable amount of knowledge relating to the production of electricity from central receiver power plants. This body of knowledge is under examination by researchers from the United States and the Federal Republic of Germany for the purpose of defining the next generation central receiver electricity producers. This second generation power plant is expected to represent a significant step towards commercialization of these systems. During the course of the study, specific activities needed to realize this next-step technology are being defined. The study is an international team effort. Under the International Energy Agency Small Solar Power Systems project, researchers from DLR, Interatom, Sandia National Laboratories, and Bechtel have designed a study in which technologies relating to existing systems are quantified, logical next-step systems are characterized, and future potential advances are identified. The receiver concepts under investigation are: salt-in-tube, volumetric, and direct absorption. Two plant performance levels are examined, 30 and 100 MW(sub e). Each concept is applied with common capacity factors, solar multiples, and types and sizes of heliostats at each performance level. Availability and uncertainty analyses are also performed. Annual energy production figures are calculated using the SOLERGY computer code. Capital and Operation and Maintenance cost methodologies are mutually agreed upon in order that levelized energy cost calculations will be consistent for each power plant. During the course of this effort, further potential advances in central receiver technology have continued to become apparent. These possible areas for improvement will be described. An additional comparison is being made between central receivers and trough-based systems.

  1. Comparison of Established and Emerging Biodosimetry Assays

    PubMed Central

    Rothkamm, K.; Beinke, C.; Romm, H.; Badie, C.; Balagurunathan, Y.; Barnard, S.; Bernard, N.; Boulay-Greene, H.; Brengues, M.; De Amicis, A.; De Sanctis, S.; Greither, R.; Herodin, F.; Jones, A.; Kabacik, S.; Knie, T.; Kulka, U.; Lista, F.; Martigne, P.; Missel, A.; Moquet, J.; Oestreicher, U.; Peinnequin, A.; Poyot, T.; Roessler, U.; Scherthan, H.; Terbrueggen, B.; Thierens, H.; Valente, M.; Vral, A.; Zenhausern, F.; Meineke, V.; Braselmann, H.; Abend, M.

    2014-01-01

    Rapid biodosimetry tools are required to assist with triage in the case of a large-scale radiation incident. Here, we aimed to determine the dose-assessment accuracy of the well-established dicentric chromosome assay (DCA) and cytokinesis-block micronucleus assay (CBMN) in comparison to the emerging γ-H2AX foci and gene expression assays for triage mode biodosimetry and radiation injury assessment. Coded blood samples exposed to 10 X-ray doses (240 kVp, 1 Gy/min) of up to 6.4 Gy were sent to participants for dose estimation. Report times were documented for each laboratory and assay. The mean absolute difference (MAD) of estimated doses relative to the true doses was calculated. We also merged doses into binary dose categories of clinical relevance and examined accuracy, sensitivity and specificity of the assays. Dose estimates were reported by the first laboratories within 0.3–0.4 days of receipt of samples for the γ-H2AX and gene expression assays compared to 2.4 and 4 days for the DCA and CBMN assays, respectively. Irrespective of the assay we found a 2.5–4-fold variation of interlaboratory accuracy per assay and lowest MAD values for the DCA assay (0.16 Gy) followed by CBMN (0.34 Gy), gene expression (0.34 Gy) and γ-H2AX (0.45 Gy) foci assay. Binary categories of dose estimates could be discriminated with equal efficiency for all assays, but at doses ≥1.5 Gy a 10% decrease in efficiency was observed for the foci assay, which was still comparable to the CBMN assay. In conclusion, the DCA has been confirmed as the gold standard biodosimetry method, but in situations where speed and throughput are more important than ultimate accuracy, the emerging rapid molecular assays have the potential to become useful triage tools. PMID:23862692

  2. Comparison of Weather Shows in Eastern Europe

    NASA Astrophysics Data System (ADS)

    Najman, M.

    2009-09-01

    Comparison of Weather Shows in Eastern Europe Television weather shows in Eastern Europe have in most cases in the high graphical standard. There is though a wast difference in duration and information content in the weather shows. There are few signs and regularities by which we can see the character of the weather show. The main differences are mainly caused by the income structure of the TV station. Either it is a fully privately funded TV relying on the TV commercials income. Or it is a public service TV station funded mainly by the national budget or fixed fee structure/tax. There are wast differences in duration and even a graphical presentation of the weather. Next important aspect is a supplier of the weather information and /or the processor. Shortly we can say, that when the TV show is produced by the national met office, the TV show consists of more scientific terms, synoptic maps, satellite imagery, etc. If the supplier is the private meteorological company, the weather show is more user-friendly, laical with less scientific terms. We are experiencing a massive shift in public weather knowledge and demand for information. In the past, weather shows consisted only of maps with weather icons. In todaýs world, even the laic weather shows consist partly of numerical weather model outputs - they are of course designed to be understandable and graphically attractive. Outputs of the numerical weather models used to be only a part of daily life of a professional meteorologist, today they are common part of life of regular people. Video samples are a part of this presentation.

  3. Comparison of several methods for BAP measurement.

    PubMed

    Nakajima, J; Murata, Y; Sakamoto, M

    2006-01-01

    It has been more important for management of water quality to estimate the amount of bioavailable phosphorus (BAP) in suspended solids (SS) entering lakes and estuaries. AGP test or extraction by 0.1 mol l(-1) NaOH (C-BOD) is widely used. Recently, highly bioavailable phosphorus (HBAP) was introduced to indicate a more easily soluble and bioavailable fraction using successive extraction by 0.1 mol l(-1) HCl and 0.1 mol l(-1) NaOH. New biologically measured BAP (B-BAP) using bacterial respiration activity was introduced in this paper. B-BAP was estimated from oxygen uptake rate (OUR), which was measured by a respiratory meter for BOD measurement using a pressure sensor. B-BAP is useful for a rapid and direct measurement of phosphorus bioavailability. B-BAP, HBAP and C-BAP in river SS were measured and compared with each other. The percentages of HBAP and B-BAP to PP were large in the urban river, while the percentage of NaOH-P or C-BAP was large in the rivers flowing in agricultural areas. By comparison with phosphorus fractions in paddy soil and activated sludge it was suggested that SS in the rivers flowing in agricultural areas mainly consisted of clay, silt or sand, while the SS in the urban river consisted of a large percentage of organic particles as well. Phosphorus in SS was suggested to be more easily bioavailable in the urban river than the rivers in agricultural areas. The ratio of C-BAP/B-BAP was large in the rivers in agricultural areas and small in the urban river. As HBAP contents were almost similar to B-BAP contents in the river SS, HBAP can be a suitable index of phosphorus indicating easily and rapidly the bioavailable fraction in SS.

  4. ENCORE: Software for Quantitative Ensemble Comparison.

    PubMed

    Tiberti, Matteo; Papaleo, Elena; Bengtsen, Tone; Boomsma, Wouter; Lindorff-Larsen, Kresten

    2015-10-01

    There is increasing evidence that protein dynamics and conformational changes can play an important role in modulating biological function. As a result, experimental and computational methods are being developed, often synergistically, to study the dynamical heterogeneity of a protein or other macromolecules in solution. Thus, methods such as molecular dynamics simulations or ensemble refinement approaches have provided conformational ensembles that can be used to understand protein function and biophysics. These developments have in turn created a need for algorithms and software that can be used to compare structural ensembles in the same way as the root-mean-square-deviation is often used to compare static structures. Although a few such approaches have been proposed, these can be difficult to implement efficiently, hindering a broader applications and further developments. Here, we present an easily accessible software toolkit, called ENCORE, which can be used to compare conformational ensembles generated either from simulations alone or synergistically with experiments. ENCORE implements three previously described methods for ensemble comparison, that each can be used to quantify the similarity between conformational ensembles by estimating the overlap between the probability distributions that underlie them. We demonstrate the kinds of insights that can be obtained by providing examples of three typical use-cases: comparing ensembles generated with different molecular force fields, assessing convergence in molecular simulations, and calculating differences and similarities in structural ensembles refined with various sources of experimental data. We also demonstrate efficient computational scaling for typical analyses, and robustness against both the size and sampling of the ensembles. ENCORE is freely available and extendable, integrates with the established MDAnalysis software package, reads ensemble data in many common formats, and can work with large

  5. Comparison of eigensolvers for symmetric band matrices

    PubMed Central

    Moldaschl, Michael; Gansterer, Wilfried N.

    2014-01-01

    We compare different algorithms for computing eigenvalues and eigenvectors of a symmetric band matrix across a wide range of synthetic test problems. Of particular interest is a comparison of state-of-the-art tridiagonalization-based methods as implemented in Lapack or Plasma on the one hand, and the block divide-and-conquer (BD&C) algorithm as well as the block twisted factorization (BTF) method on the other hand. The BD&C algorithm does not require tridiagonalization of the original band matrix at all, and the current version of the BTF method tridiagonalizes the original band matrix only for computing the eigenvalues. Avoiding the tridiagonalization process sidesteps the cost of backtransformation of the eigenvectors. Beyond that, we discovered another disadvantage of the backtransformation process for band matrices: In several scenarios, a lot of gradual underflow is observed in the (optional) accumulation of the transformation matrix and in the (obligatory) backtransformation step. According to the IEEE 754 standard for floating-point arithmetic, this implies many operations with subnormal (denormalized) numbers, which causes severe slowdowns compared to the other algorithms without backtransformation of the eigenvectors. We illustrate that in these cases the performance of existing methods from Lapack and Plasma reaches a competitive level only if subnormal numbers are disabled (and thus the IEEE standard is violated). Overall, our performance studies illustrate that if the problem size is large enough relative to the bandwidth, BD&C tends to achieve the highest performance of all methods if the spectrum to be computed is clustered. For test problems with well separated eigenvalues, the BTF method tends to become the fastest algorithm with growing problem size. PMID:26594079

  6. Comparison of Electrophysiological Auditory Measures in Fishes.

    PubMed

    Maruska, Karen P; Sisneros, Joseph A

    2016-01-01

    Sounds provide fishes with important information used to mediate behaviors such as predator avoidance, prey detection, and social communication. How we measure auditory capabilities in fishes, therefore, has crucial implications for interpreting how individual species use acoustic information in their natural habitat. Recent analyses have highlighted differences between behavioral and electrophysiologically determined hearing thresholds, but less is known about how physiological measures at different auditory processing levels compare within a single species. Here we provide one of the first comparisons of auditory threshold curves determined by different recording methods in a single fish species, the soniferous Hawaiian sergeant fish Abudefduf abdominalis, and review past studies on representative fish species with tuning curves determined by different methods. The Hawaiian sergeant is a colonial benthic-spawning damselfish (Pomacentridae) that produces low-frequency, low-intensity sounds associated with reproductive and agonistic behaviors. We compared saccular potentials, auditory evoked potentials (AEP), and single neuron recordings from acoustic nuclei of the hindbrain and midbrain torus semicircularis. We found that hearing thresholds were lowest at low frequencies (~75-300 Hz) for all methods, which matches the spectral components of sounds produced by this species. However, thresholds at best frequency determined via single cell recordings were ~15-25 dB lower than those measured by AEP and saccular potential techniques. While none of these physiological techniques gives us a true measure of the auditory "perceptual" abilities of a naturally behaving fish, this study highlights that different methodologies can reveal similar detectable range of frequencies for a given species, but absolute hearing sensitivity may vary considerably.

  7. Comparison-Bot: an Automated Preliminary-Final Report Comparison System.

    PubMed

    Kalaria, Amit D; Filice, Ross W

    2016-06-01

    Regular comparison of preliminary to final reports is a critical part of radiology resident and fellow education as prior research has documented substantial preliminary to final discrepancies. Unfortunately, there are many barriers to this comparison: high study volume; overnight rotations without an attending; the ability to finalize reports remotely; the subtle nature of many changes; and lack of easy access to the preliminary report after finalization. We developed a system that automatically compiles and emails a weekly summary of report differences for all residents and fellows. Trainees can also create a custom report using a date range of their choice and can view this data on a resident dashboard. Differences between preliminary and final reports are clearly highlighted with links to the associated study in Picture Archiving and Communication Systems (PACS) for efficient review and learning. Reports with more changes, particularly changes made in the impression, are highlighted to focus attention on those exams with substantive edits. Our system provides an easy way for trainees to review changes to preliminary reports with immediate access to the associated images, thereby improving their educational experience. Departmental surveys showed that our report difference summary is easy to understand and improves the educational experience of our trainees. Additionally, interesting descriptive statistics help us understand how reports are changed by trainee level, by attending, and by exam type. Finally, this system can be easily ported to other departments who have access to their Health Level 7 (HL7) data. PMID:26537931

  8. Comparison of marine productivity among Outer Continental Shelf planning areas

    SciTech Connect

    Darnell, R.M.

    1991-04-01

    Continental Shelf Associates was contracted to update and expand an earlier work on a comparison of primary productivity among Outer Continental Shelf (OCS) planning areas. The update consists of four general objectives. This report addresses the fourth objective, the potential to use measures of marine secondary productivity in determining relative rankings of the OCS planning area. Ideally, comparisons of secondary productivity among diverse geographic areas would take an ecosystem perspective. However, there is not enough ecosystem-level understanding to allow a comparison on that basis. The report focuses on individual species and group of species. Zooplankton and benthic communities represent major portions of the marine ecosystems and would be the preferred subjects for comparative studies. At this time comparisons of secondary productivity among planning areas would be difficult with existing databases. It is unlikely this situation will improve in the near future.

  9. COMPARISON OF BIOLOGICAL COMMUNITIES: THE PROBLEM OF SAMPLE REPRESENTATIVENESS

    EPA Science Inventory

    Obtaining an adequate, representative sample of biological communities or assemblages to make richness or compositional comparisons among sites is a continuing challenge. Traditionally, sample size is based on numbers of replicates or area collected or numbers of individuals enum...

  10. Appearance comparison in individuals with body dysmorphic disorder and controls.

    PubMed

    Anson, Martin; Veale, David; Miles, Sarah

    2015-09-01

    Research investigating appearance comparison in body dysmorphic disorder (BDD) remains very limited, despite the fact that this is one of the most commonly observed behaviors in individuals with the disorder. The present study investigated the self-reported extent and nature of appearance comparison in 35 BDD participants relative to 45 controls using a newly devised and a standardized appearance comparison measure. The results showed that BDD participants reported significantly higher levels of appearance comparison than controls. Individuals with BDD also reported greater levels of comparing in terms of the specific feature(s) of their appearance they were most concerned about as compared to overall appearance, whilst controls showed the opposite pattern. Levels of comparing in BDD participants increased as targets increased in terms of attractiveness, and individuals with BDD rated themselves as being markedly less attractive than targets, and feeling markedly less satisfied with their appearance after comparing. Cognitive-behavioral treatment implications are discussed. PMID:26379252

  11. Comparison of Accreditation Criteria: CBHDP, NLN, and COA Accreditation Criteria.

    ERIC Educational Resources Information Center

    Frels, Lois; Horton, Betty

    1991-01-01

    Presents a detailed comparison of similarities and differences in the accreditation criteria of two nursing accrediting agencies--the National League for Nursing and the Council on Accreditation--as they relate to nurse anesthesiology programs. (JOW)

  12. Operating Reserves and Wind Power Integration: An International Comparison; Preprint

    SciTech Connect

    Milligan, M.; Donohoo, P.; Lew, D.; Ela, E.; Kirby, B.; Holttinen, H.; Lannoye, E.; Flynn, D.; O'Malley, M.; Miller, N.; Eriksen, P. B.; Gottig, A.; Rawn, B.; Gibescu, M.; Lazaro, E. G.; Robitaille, A.; Kamwa, I.

    2010-10-01

    This paper provides a high-level international comparison of methods and key results from both operating practice and integration analysis, based on an informal International Energy Agency Task 25: Large-scale Wind Integration.

  13. Comparison Campaign of VLBI Data Analysis Software - First Results

    NASA Technical Reports Server (NTRS)

    Plank, Lucia; Bohm, Johannes; Schuh, Harald

    2010-01-01

    During the development of the Vienna VLBI Software VieVS at the Institute of Geodesy and Geophysics at Vienna University of Technology, a special comparison setup was developed with the goal of easily finding links between deviations of results achieved with different software packages and certain parameters of the observation. The object of comparison is the computed time delay, a value calculated for each observation including all relevant models and corrections that need to be applied in geodetic VLBI analysis. Besides investigating the effects of the various models on the total delay, results of comparisons between VieVS and Occam 6.1 are shown. Using the same methods, a Comparison Campaign of VLBI data analysis software called DeDeCC is about to be launched within the IVS soon.

  14. Radioxenon standards used in laboratory inter-comparisons.

    PubMed

    Gohla, H; Auer, M; Cassette, Ph; Hague, R K; Lechermann, M; Nadalut, B

    2016-03-01

    Preparation methods for (133)Xe standards of activity concentration and the results of the 2014 (133)Xe laboratory inter-comparison exercise are described. One element of the quality assurance/quality control (QA/QC) program for laboratories of the International Monitoring System (IMS) will be regular inter-comparison exercises. However, until recently, no activity concentration standards for benchmarking were available. Therefore, two (133)Xe activity concentration reference standards were produced independently by Idaho National Laboratory and Seibersdorf Laboratories and used for the 2014 laboratory inter-comparison exercise. The preparation of a complementary (127)Xe activity concentration standard as well as a (127)Xe laboratory inter-comparison exercise suggests (127)Xe as a suitable isotope for QA/QC of remote IMS noble gas stations.

  15. CCM key comparison CCM.D-K4 'Hydrometer'

    NASA Astrophysics Data System (ADS)

    Lorefice, S.; Becerra, L. O.; Lenard, E.; Lee, Y. J.; Lee, W. G.; Madec, T.; Meury, P. A.; Caceres, J.; Santos, C.; Vamossy, C.; Man, J.; Fen, K.; Toda, K.; Wright, J.; Bettin, H.; Toth, H.

    2016-01-01

    This report presents the comparison philosophy, methodology, analysis and the results of the designed CCM.D-K4 key comparison that covered the calibration of high resolution hydrometers for liquid and alcoholometers in the density range 600 kg/m3 to 2000 kg/m3 at the temperature of 20°C. The main purpose of this comparison was not only to evaluate the degree of equivalence in the calibration of high accuracy hydrometers between NMI participants, but also to link, were it is possible, the results of previous comparisons to Key Comparison Reference Values (KCRVs) of CCM.D-K4. Eleven NMI laboratories took part in the CCM.D-K4 divided in two groups (petals). With the CCM.D-K4 purpose, two similar sets consisting of three hydrometers for liquid density determinations and an alcoholometer were circulated to the NMI participants as a travelling standard in the time interval from January 2011 to April 2012. Twelve Key Comparison Reference Values (KCRVs) for each petal have been obtained at the density values related to the tested density marks of the transfer standards by the results of participants. The KCRVs and corresponding uncertainties were calculated by the weighted mean in the case of consistent results, otherwise the median was used. The degree of equivalence (DoE) with respect to the corresponding KCRV was determined for each participant and, in this particular comparison, the Weighted Least Squares (WLS) method was used to link the individual DoE of each participant by a continuous function. Significant drift of the transfer standards was not detected. This report also gives instructions on calculating pair-wise degrees of equivalence, with the addition of any information on correlations that may be necessary to estimate more accurately as well as the procedure for linking international comparisons to the CCM.D-K4. Finally an example of linkage to the CCM.D-K4 is given by dealing with the results of the bilateral comparison between INRiM and NMIA, which was

  16. COMPARISON OF ECOLOGICAL COMMUNITIES: THE PROBLEM OF SAMPLE REPRESENTATIVENESS

    EPA Science Inventory

    Obtaining an adequate, representative sample of ecological communities to make taxon richness (TR) or compositional comparisons among sites is a continuing challenge. Sample representativeness literally means the similarity in species composition and relative abundance between a ...

  17. A Simple Illustration for the Need of Multiple Comparison Procedures

    ERIC Educational Resources Information Center

    Carter, Rickey E.

    2010-01-01

    Statistical adjustments to accommodate multiple comparisons are routinely covered in introductory statistical courses. The fundamental rationale for such adjustments, however, may not be readily understood. This article presents a simple illustration to help remedy this.

  18. Genuine and drug-induced synesthesia: a comparison.

    PubMed

    Sinke, Christopher; Halpern, John H; Zedler, Markus; Neufeld, Janina; Emrich, Hinderk M; Passie, Torsten

    2012-09-01

    Despite some principal similarities, there is no systematic comparison between the different types of synesthesia (genuine, acquired and drug-induced). This comprehensive review compares the three principal types of synesthesia and focuses on their phenomenological features and their relation to different etiological models. Implications of this comparison for the validity of the different etiological models are discussed. Comparison of the three forms of synesthesia show many more differences than similarities. This is in contrast to their representation in the literature, where they are discussed in many respects as being virtually similar. Noteworthy is the much broader spectrum and intensity with the typical drug-induced synesthesias compared to genuine and acquired synesthesias. A major implication of the phenomenological comparison in regard to the etiological models is that genuine and acquired synesthesias point to morphological substrates, while drug-induced synesthesia appears to be based on functional changes of brain activity.

  19. Appearance comparison in individuals with body dysmorphic disorder and controls.

    PubMed

    Anson, Martin; Veale, David; Miles, Sarah

    2015-09-01

    Research investigating appearance comparison in body dysmorphic disorder (BDD) remains very limited, despite the fact that this is one of the most commonly observed behaviors in individuals with the disorder. The present study investigated the self-reported extent and nature of appearance comparison in 35 BDD participants relative to 45 controls using a newly devised and a standardized appearance comparison measure. The results showed that BDD participants reported significantly higher levels of appearance comparison than controls. Individuals with BDD also reported greater levels of comparing in terms of the specific feature(s) of their appearance they were most concerned about as compared to overall appearance, whilst controls showed the opposite pattern. Levels of comparing in BDD participants increased as targets increased in terms of attractiveness, and individuals with BDD rated themselves as being markedly less attractive than targets, and feeling markedly less satisfied with their appearance after comparing. Cognitive-behavioral treatment implications are discussed.

  20. Clinical Comparison of Haloperidol with Chlorpromazine in Mentally Retarded Children

    ERIC Educational Resources Information Center

    LeVann, Leonard J.

    1971-01-01

    In an 8-week double-blind comparison, haloperidol reduced the severity of the target symptoms impulsiveness, hostility, and aggressiveness in significantly more mentally retarded children than did chlorpromazine. (Author)

  1. COMPARISON OF METHODS FOR MEASURING CONCENTRATIONS OF SEMIVOLATILE PARTICULATE MATTER

    EPA Science Inventory

    The paper gives results of a comparison of methods for measuring concentrations of semivolatile particulate matter (PM) from indoor-environment, small, combustion sources. Particle concentration measurements were compared for methods using filters and a small electrostatic precip...

  2. Comparison of Nutrient Drivers and Response Metrics in Oregon Estuaries

    EPA Science Inventory

    With the goal of assessing sensitivity to nutrient enrichment, we present a cross-estuary comparison of nutrient sources, levels, and biological responses (phytoplankton and macroalgae) for thirteen Oregon estuaries. Nitrogen levels in the upstream portions of the estuaries are ...

  3. Role and Evaluation of Interlaboratory Comparison Results in Laboratory Accreditation

    SciTech Connect

    Bode, P.

    2008-08-14

    Participation in interlaboratory comparisons provides laboratories an opportunity for independent assessment of their analytical performance, both in absolute way and in comparison with those by other techniques. However, such comparisons are hindered by differences in the way laboratories participate, e.g. at best measurement capability or under routine conditions. Neutron activation analysis laboratories, determining total mass fractions, often see themselves classified as 'outliers' since the majority of other participants employ techniques with incomplete digestion methods. These considerations are discussed in relation to the way results from interlaboratory comparisons are evaluated by accreditation bodies following the requirements of Clause 5.9.1 of the ISO/IEC 17025:2005. The discussion and conclusions come largely forth from experiences in the author's own laboratory.

  4. Role and Evaluation of Interlaboratory Comparison Results in Laboratory Accreditation

    NASA Astrophysics Data System (ADS)

    Bode, P.

    2008-08-01

    Participation in interlaboratory comparisons provides laboratories an opportunity for independent assessment of their analytical performance, both in absolute way and in comparison with those by other techniques. However, such comparisons are hindered by differences in the way laboratories participate, e.g. at best measurement capability or under routine conditions. Neutron activation analysis laboratories, determining total mass fractions, often see themselves classified as `outliers' since the majority of other participants employ techniques with incomplete digestion methods. These considerations are discussed in relation to the way results from interlaboratory comparisons are evaluated by accreditation bodies following the requirements of Clause 5.9.1 of the ISO/IEC 17025:2005. The discussion and conclusions come largely forth from experiences in the author's own laboratory.

  5. Characterization and comparison of emissions from rudimentary waste disposal technologies

    EPA Science Inventory

    Results from 2011 simulation of burn pit emissions and air curtain incinerator emissions, recent developments in methods for open air sampling, comparison of waste energy technologies, current SERDP programs in this area.

  6. Comparisons of Remote And In-situ CME Features

    NASA Astrophysics Data System (ADS)

    Reinard, Alysha; Mulligan, T.; Lynch, B.

    2011-05-01

    We present a comparison of remote and in-situ CME ejecta using data from the Ulysses and SOHO missions. Quadrature occurs when two spacecraft form a 90 degree angle with the Sun. Quadrature studies allow the comparison of visible features of limb CMEs and and in-situ ICME properties. We investigate several events, including so-called "cannibal" CMEs, and compare the relationship between CME morphology and in-situ structures such as magnetic field, composition, and plasma properties.

  7. A Comparison of Cross-Sector Cyber Security Standards

    SciTech Connect

    Robert P. Evans

    2005-09-01

    This report presents a review and comparison (commonality and differences) of three cross-sector cyber security standards and an internationally recognized information technology standard. The comparison identifies the security areas covered by each standard and reveals where the standards differ in emphasis. By identifying differences in the standards, the user can evaluate which standard best meets their needs. For this report, only cross-sector standards were reviewed.

  8. Comparisons organized by Ionizing Radiation Metrology Laboratory of FTMC, Lithuania.

    PubMed

    Gudelis, A; Gorina, I

    2016-03-01

    The newly established Ionizing Radiation Metrology Laboratory of the National Metrology Institute (FTMC) in Lithuania organized four comparisons in the field of low-level radioactivity measurements in water. For gamma-ray emitters, the activity concentration in the samples was in the range 1-25Bq/kg, while for tritium it was around 2Bq/g. The assigned values of all comparisons were traceable to the primary standards of the Czech Metrology Institute (CMI). PMID:26585643

  9. Comparison groups on bills: Automated, personalized energy information

    SciTech Connect

    Iyer, Maithili; Kempton, Willett; Payne, Christopher

    2006-07-01

    A program called ``Innovative Billing?? has been developed to provide individualized energy information for a mass audience?the entireresidential customer base of an electric or gas utility. Customers receive a graph on the bill that compares that customer?s consumption with othersimilar customers for the same month. The program aims to stimulate customers to make ef?ciency improvements. To group as many as severalmillion customers into small ``comparison groups??, an automated method must be developed drawing solely from the data available to the utility.This paper develops and applies methods to compare the quality of resulting comparison groups.A data base of 114,000 customers from a utility billing system was used to evaluate Innovative Billing comparison groups, comparing fouralternative criteria: house characteristics (?oor area, housing type, and heating fuel); street; meter read route; billing cycle. Also, customers wereinterviewed to see what forms of comparison graphs made most sense and led to fewest errors of interpretation. We ?nd that good qualitycomparison groups result from using street name, meter book, or multiple house characteristics. Other criteria we tested, such as entire cycle, entiremeter book, or single house characteristics such as ?oor area, resulted in poor quality comparison groups. This analysis provides a basis forchoosing comparison groups based on extensive user testing and statistical analysis. The result is a practical set of guidelines that can be used toimplement realistic, inexpensive innovative billing for the entire customer base of an electric or gas utility.

  10. Social Comparison Manifests in Event-related Potentials

    PubMed Central

    Luo, Yi; Feng, Chunliang; Wu, Tingting; Broster, Lucas S.; Cai, Huajian; Gu, Ruolei; Luo, Yue-jia

    2015-01-01

    Social comparison, a widespread phenomenon in human society, has been found to affect outcome evaluation. The need to belong to a social group may result in distinct neural responses to diverse social comparison outcomes. To extend previous studies by examining how social comparison with hierarchical characteristics is temporally processed, electroencephalography responses were recorded in the current study. Participants played a lottery game with two pseudo-players simultaneously and received both their own and the other two players’ outcomes. Results of three event-related potential components, including the P2, the feedback-related negativity (FRN), and the late positive component (LPC), indicate that social comparison manifests in three stages. First, outcomes indicating a different performance from others elicited a larger P2 than evenness. Second, the FRN showed hierarchical sensitivity to social comparison outcomes. This effect manifested asymmetrically. Finally, large difference between the participant’s outcome and the other two players’ evoked a larger LPC than the medium difference and the even condition. We suggest that during social comparison, people detect if there is any difference between self and others, and then evaluate the information of this difference hierarchically, and finally interpret the situations in which oneself deviates from the group as most motivationally salient. PMID:26183734

  11. The envious brain: the neural basis of social comparison.

    PubMed

    Dvash, Jonathan; Gilam, Gadi; Ben-Ze'ev, Aharon; Hendler, Talma; Shamay-Tsoory, Simone G

    2010-11-01

    Humans have a drive to evaluate themselves by examining their abilities and outcomes in comparison to others. The present study examined the emotional and neural correlates of upward social comparison (comparison with those who have more) and downward social comparison (comparison with those who have less). Two experiments were conducted with volunteers in an interactive game of chance, in which a putative player won or lost more money than the participant. The results showed that even when participants lost money, they expressed joy and schadenfreude (gloating) if the other player had lost more money. On the other hand when they actually won money, but the other player had won more they expressed envy. This pattern was also demonstrated in a differential BOLD response in the ventral striatum. Comparing the activations between an actual gain and a relative gain indicated that even when a person loses money, merely adding information about another person's greater loss may increase ventral striatum activations to a point where these activations are similar to those of an actual gain. We suggest that the ventral striatum plays a role in mediating the emotional consequences of social comparison. PMID:20205244

  12. Changes in latent fingerprint examiners' markup between analysis and comparison.

    PubMed

    Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

    2015-02-01

    After the initial analysis of a latent print, an examiner will sometimes revise the assessment during comparison with an exemplar. Changes between analysis and comparison may indicate that the initial analysis of the latent was inadequate, or that confirmation bias may have affected the comparison. 170 volunteer latent print examiners, each randomly assigned 22 pairs of prints from a pool of 320 total pairs, provided detailed markup documenting their interpretations of the prints and the bases for their comparison conclusions. We describe changes in value assessments and markup of features and clarity. When examiners individualized, they almost always added or deleted minutiae (90.3% of individualizations); every examiner revised at least some markups. For inconclusive and exclusion determinations, changes were less common, and features were added more frequently when the image pair was mated (same source). Even when individualizations were based on eight or fewer corresponding minutiae, in most cases some of those minutiae had been added during comparison. One erroneous individualization was observed: the markup changes were notably extreme, and almost all of the corresponding minutiae had been added during comparison. Latents assessed to be of value for exclusion only (VEO) during analysis were often individualized when compared to a mated exemplar (26%); in our previous work, where examiners were not required to provide markup of features, VEO individualizations were much less common (1.8%). PMID:25553355

  13. The differing roles of comparison and contrast in children's categorization.

    PubMed

    Namy, Laura L; Clepper, Lauren E

    2010-11-01

    Comparison of perceptually similar exemplars from an object category encourages children to overlook compelling perceptual similarities and use relational and functional properties more relevant for taxonomic categorization. This article investigates whether showing children a contrasting object that is perceptually similar but out of kind serves the same function as comparison in heightening children's attention to taxonomically relevant features. In this study, 4-year-olds completed a forced-choice categorization task in which they viewed exemplars from a target category and then selected among (a) a perceptually similar out-of-kind object, (b) a category member that differed perceptually from the exemplars, and (c) a thematically related object. Children were assigned to one of four conditions: No-Compare/No-Contrast, Compare/No-Contrast, No-Compare/Contrast, or Compare/Contrast. As in previous work, comparison increased the frequency of category responses, but there was no effect of contrast on categorization. However, only those in the Compare/Contrast condition displayed consistently taxonomic patterns of responding. Follow-up studies revealed that the effect of comparison plus contrast was evident only when comparison preceded, rather than followed, contrast information and that the value added by providing contrastive information is not attributable to the perceptual similarity between the category exemplars and the contrast object. Comparison and contrast make differing contributions to children's categorization. PMID:20609449

  14. Social Comparison Manifests in Event-related Potentials.

    PubMed

    Luo, Yi; Feng, Chunliang; Wu, Tingting; Broster, Lucas S; Cai, Huajian; Gu, Ruolei; Luo, Yue-jia

    2015-01-01

    Social comparison, a widespread phenomenon in human society, has been found to affect outcome evaluation. The need to belong to a social group may result in distinct neural responses to diverse social comparison outcomes. To extend previous studies by examining how social comparison with hierarchical characteristics is temporally processed, electroencephalography responses were recorded in the current study. Participants played a lottery game with two pseudo-players simultaneously and received both their own and the other two players' outcomes. Results of three event-related potential components, including the P2, the feedback-related negativity (FRN), and the late positive component (LPC), indicate that social comparison manifests in three stages. First, outcomes indicating a different performance from others elicited a larger P2 than evenness. Second, the FRN showed hierarchical sensitivity to social comparison outcomes. This effect manifested asymmetrically. Finally, large difference between the participant's outcome and the other two players' evoked a larger LPC than the medium difference and the even condition. We suggest that during social comparison, people detect if there is any difference between self and others, and then evaluate the information of this difference hierarchically, and finally interpret the situations in which oneself deviates from the group as most motivationally salient. PMID:26183734

  15. Changes in latent fingerprint examiners' markup between analysis and comparison.

    PubMed

    Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

    2015-02-01

    After the initial analysis of a latent print, an examiner will sometimes revise the assessment during comparison with an exemplar. Changes between analysis and comparison may indicate that the initial analysis of the latent was inadequate, or that confirmation bias may have affected the comparison. 170 volunteer latent print examiners, each randomly assigned 22 pairs of prints from a pool of 320 total pairs, provided detailed markup documenting their interpretations of the prints and the bases for their comparison conclusions. We describe changes in value assessments and markup of features and clarity. When examiners individualized, they almost always added or deleted minutiae (90.3% of individualizations); every examiner revised at least some markups. For inconclusive and exclusion determinations, changes were less common, and features were added more frequently when the image pair was mated (same source). Even when individualizations were based on eight or fewer corresponding minutiae, in most cases some of those minutiae had been added during comparison. One erroneous individualization was observed: the markup changes were notably extreme, and almost all of the corresponding minutiae had been added during comparison. Latents assessed to be of value for exclusion only (VEO) during analysis were often individualized when compared to a mated exemplar (26%); in our previous work, where examiners were not required to provide markup of features, VEO individualizations were much less common (1.8%).

  16. Comparison between Dione’ and Enceladus’ terrain units

    NASA Astrophysics Data System (ADS)

    Scipioni, Francesca; Tosi, F.; Stephan, K.; Filacchione, G.; Capaccioni, F.; Cerroni, P.

    2013-10-01

    of water ice coming from the E-ring, deposits on Dione’s leading hemisphere, making this side of brighter than the trailing hemisphere. Therefore, a comparison between Dione and Enceladus spectra is crucial to quantify the effectiveness of this mechanism.

  17. Comparison between Dione' and Enceladus' terrain units

    NASA Astrophysics Data System (ADS)

    Scipioni, F.; Tosi, F.; Stephan, K.; Filacchione, G.; Ciarniello, M.; Cerroni, P.

    2013-12-01

    water ice coming from the E-ring, deposits on Dione's leading hemisphere, making this side of brighter than the trailing hemisphere. Therefore, a comparison between Dione and Enceladus spectra is crucial to quantify the effectiveness of this mechanism.

  18. A Comparison of High-Voltage Switches

    SciTech Connect

    Chu, K.W.; Scott, G.L.

    1999-02-01

    This report summarizes our work on high-voltage switches during the past few years. With joint funding from the Department of Energy (DOE) and the Department of Defense (DOD), we tested a wide variety of switches to a common standard. This approach permitted meaningful comparisons between disparate switches. Most switches were purchased from commercial sources, though some were experimental devices. For the purposes of this report, we divided the switches into three generic types (gas, vacuum, and semiconductor) and selected data that best illustrates important strengths and weaknesses of each switch type. Test techniques that indicate the state of health of the switches are emphasized. For example, a good indicator of residual gas in a vacuum switch is the systematic variation of the switching delay in response to changes in temperature and/or operating conditions. We believe that the presentation of this kind of information will help engineers to select and to test switches for their particular applications. Our work was limited to switches capable of driving slappers. Also known as exploding-foil initiators, slappers are detonators that initiate a secondary explosive by direct impact with a small piece of matter moving at the detonation velocity (several thousands of meters per second). A slapper is desirable for enhanced safety (no primary explosive), but it also places extra demands on the capacitor-discharge circuit to deliver a fast-rising current pulse (greater than 10 A/ns) of several thousand amperes. The required energy is substantially less than one joule; but this energy is delivered in less than one microsecond, taking the peak power into the megawatt regime. In our study, the switches operated in the 1 kV to 3 kV range and were physically small, roughly 1 cm{sup 3} or less. Although a fuze functions only once in actual use, multiple-shot capability is important for production testing and for research work. For this reason, we restricted this report

  19. Algorithmic comparisons of decaying, isothermal, supersonic turbulence

    NASA Astrophysics Data System (ADS)

    Kitsionas, S.; Federrath, C.; Klessen, R. S.; Schmidt, W.; Price, D. J.; Dursi, L. J.; Gritschneder, M.; Walch, S.; Piontek, R.; Kim, J.; Jappsen, A.-K.; Ciecielag, P.; Mac Low, M.-M.

    2009-12-01

    Context: Simulations of astrophysical turbulence have reached such a level of sophistication that quantitative results are now starting to emerge. However, contradicting results have been reported in the literature with respect to the performance of the numerical techniques employed for its study and their relevance to the physical systems modelled. Aims: We aim at characterising the performance of a variety of hydrodynamics codes including different particle-based and grid-based techniques on the modelling of decaying supersonic turbulence. This is the first such large-scale comparison ever conducted. Methods: We modelled driven, compressible, supersonic, isothermal turbulence with an rms Mach number of M_rms ˜ 4, and then let it decay in the absence of gravity, using runs performed with four different grid codes (ENZO, FLASH, TVD, ZEUS) and three different SPH codes (GADGET, PHANTOM, VINE). We additionally analysed two calculations denoted as PHANTOM A and PHANTOM B using two different implementations of artificial viscosity in PHANTOM. We analysed the results of our numerical experiments using volume-averaged quantities like the rms Mach number, volume- and density-weighted velocity Fourier spectrum functions, and probability distribution functions of density, velocity, and velocity derivatives. Results: Our analysis indicates that grid codes tend to be less dissipative than SPH codes, though details of the techniques used can make large differences in both cases. For example, the Morris & Monaghan viscosity implementation for SPH results in less dissipation (PHANTOM B and VINE versus GADGET and PHANTOM A). For grid codes, using a smaller diffusion parameter leads to less dissipation, but results in a larger bottleneck effect (our ENZO versus FLASH runs). As a general result, we find that by using a similar number of resolution elements N for each spatial direction means that all codes (both grid-based and particle-based) show encouraging similarity of all

  20. Intercontinental comparison of caustic ingestion in children

    PubMed Central

    Rafeey, Mandana; Ghojazadeh, Morteza; Mehdizadeh, Amir; Hazrati, Hakimeh

    2015-01-01

    Purpose To investigate the caustic ingestion in children among different continents according to demographic characteristics (core purpose), main symptoms, common caustic agents, signs and symptoms, management, treatment and complications. Methods This systematic review was performed by searching the databases Science Direct, ProQuest, Google Scholar, and PubMed, electronically and manually. We included studies that were published from 1980 to 2013, at University of Medical Sciences of Tabriz, Iran. A strategic search was performed with keywords including caustic, corrosive, ingestion and children, and was limited to articles in English and Persian. Statistical analysis was performed by SPSS ver. 18. Results Of 63 selected articles of caustic ingestion with 9,888 samples, the proportion of Africa was 3 articles (4.8%) and 95 samples (1%), America 9 articles (14.3%) and 305 sample (3%), Asia 29 articles (46%) and 2,780 samples (28.1%), Europe 17 articles (27%) and 3,002 samples (30.4%), and Oceania 5 articles (7.9%) and 3,706 samples (37.5%). The average age was in the Africa 3.07±2.02 years, America 3.17±1.83 years, Asia 3.34±1.58 years, Europe 3.58±2.09 years and Oceania 3.52±2.02 years. Sex distribution was in Africa 76 males (0.91%) and 19 females (0.23%), America 49 males (0.58%) and 41 females (0.49%), Asia 1,575 males (18.76%) and 1,087 females (12.95%), Europe 1,018 males (12.13%) and 823 females (9.8%), and Oceania 1,918 males (22.85%) and 1,788 females (21.3%). Statistical analysis of the data indicated higher consumption in Europe and Oceania in the boys with higher average age of years. Conclusion The comparison of caustic ingestion indicated that the cause substances of caustic ingestion in children are different among continents, therefore prevention strategy and different treatment guidelines among continents will be needed. PMID:26770225

  1. Collective violence: comparisons between youths and chimpanzees.

    PubMed

    Wrangham, Richard W; Wilson, Michael L

    2004-12-01

    Patterns of collective violence found among humans include similarities to those seen among chimpanzees. These include participation predominantly by males, an intense personal and group concern with status, variable subgroup composition, defense of group integrity, inter-group fights that include surprise attacks, and a tendency to avoid mass confrontation. Compared to chimpanzee communities, youth gangs tend to be larger, composed of younger individuals, occupying smaller territories and having a more complex organization. Youth gangs also differ from chimpanzee communities as a result of numerous cultural and environmental influences including complex relations with non-gang society. These relations are governed in important ways by such factors as perceived economic and personal constraints, policing, family structure, and levels of poverty, crime, and racism. Nevertheless, the concepts that sociologists use to account for collective violence in youth gangs are somewhat similar to those applied by anthropologists and biologists to chimpanzees. Thus in both cases collective violence is considered to emerge partly because males are highly motivated to gain personal status, which they do by physical violence. In the case of youth gangs, the reasons for the prevalence of physical violence in status competition compared to non-gang society are clearly context-specific, both culturally and historically. By contrast, among chimpanzees the use of physical violence to settle status competition is universal (in the wild and captivity). The use of physical violence in individual status competition therefore has different sources in youth gangs and chimpanzees. Regardless of its origin, however, its combination with an intense concern for status can explain: (1) why individual males form alliances among each other; and hence (2) how such alliances generate social power, closed groups, and a capacity for defense of territory or pre-emptive attacks on rivals. This comparison

  2. Worldwide site comparison for submillimetre astronomy

    NASA Astrophysics Data System (ADS)

    Tremblin, P.; Schneider, N.; Minier, V.; Durand, G. Al.; Urban, J.

    2012-12-01

    Aims: The most important limitation for ground-based submillimetre (submm) astronomy is the broad-band absorption of the total water vapour in the atmosphere above an observation site, often expressed as the precipitable water vapour (PWV). A long-term statistic on the PWV is thus mandatory to characterize the quality of an existing or potential site for observational submm-astronomy. In this study we present a three-year statistic (2008-2010) of the PWV for ground-based telescope sites all around the world and for stratospheric altitudes relevant for SOFIA (Stratospheric Observatory for Far-Infrared Astronomy). The submm-transmission is calculated for typical PWVs using an atmospheric model. Methods: We used data from IASI (Infrared Atmospheric Sounding Interferometer) on the Metop-A satellite to retrieve water vapour profiles for each site (11 in total, comprising Antarctica, Chile, Mauna Kea, Greenland, Tibet). The use of a single instrument to make the comparison provides unbiased data with a common calibration method. The profiles are integrated above the mountain/stratospheric altitude to get an estimation of the PWV. We then applied the atmospheric model MOLIERE (Microwave Observation and LIne Estimation and REtrieval) to compute the corresponding atmospheric absorption for wavelengths between 150 μm and 3 mm. Results: We present the absolute PWV values for each site sorted by year and time percentage. The PWV corresponding to the first decile (10%) and the quartiles (25%, 50%, 75%) are calculated and transmission curves between 150 μm and 3 mm for these values are shown. The Antarctic and South-American sites present very good conditions for submillimetre astronomy. The 350 μm and 450 μm atmospheric windows are open all year long, whereas the 200 μm atmospheric window opens reasonably for 25% of the time in Antarctica and the extremely high-altitude sites in Chile. Potential interesting new facilities are Macon in Argentina and Summit in Greenland

  3. Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with ISCIII (December 2014)

    NASA Astrophysics Data System (ADS)

    Viallon, Joële; Moussay, Philippe; Idrees, Faraz; Wielgosz, Robert; Sanchez, Carmen; Morillo Gomez, Pilar

    2015-01-01

    As part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of the Instituto de Salud Carlos III (ISCIII) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount-of-substance fraction range of 0 nmol/mol to 500 nmol/mol. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  4. Bilateral comparison of cryogenic radiometers between NPL and UME, linked to the CCPR-S3 supplementary comparison

    NASA Astrophysics Data System (ADS)

    Goodman, T.

    2016-01-01

    This report presents the results of a bilateral comparison between NPL and UME, which was carried out to establish the unilateral degrees of equivalence for UME with respect to the defined reference value of the CCPR S3 supplementary comparison of cryogenic radiometers using silicon trap detectors as transfer devices. In accordance with the protocol for the CCPR S3 comparison, UME was asked to calibrate a set of NPL supplied silicon trap transfer detectors at a series of laser wavelengths; UME chose to measure at 514.5 nm and 632.8 nm. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCPR, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  5. SUPPLEMENTARY COMPARISON Final report on EUROMET.L-S19 (EUROMET Project 910): Comparison of squareness measurements

    NASA Astrophysics Data System (ADS)

    Mokros, Jiri

    2010-01-01

    A bilateral comparison has been undertaken between two European national metrology institutes (NMIs) in the subject field of squareness measurement. Specifically, both NMIs made measurements of a cylindrical squareness standard, made of steel. Both participants made measurements of the internal angles at several positions around the circumference, as well as measurement of the corresponding straightness profiles. The report lists the results obtained by both participants, as well as an analysis of the results and their uncertainties. The results are in good agreement with one another. This bilateral comparison followed the same technical protocol as a previous supplementary comparison (EUROMET.L-S10). Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by EURAMET, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  6. Final report of the regional key comparison EURAMET.M.G-K1: European Comparison of Absolute Gravimeters ECAG-2011

    NASA Astrophysics Data System (ADS)

    Francis, Olivier; Klein, Gilbert; Baumann, Henri; Dando, Nicolas; Tracey, Ray; Ullrich, Christian; Castelein, Stefaan; Hua, Hu; Kang, Wu; Chongyang, Shen; Songbo, Xuan; Hongbo, Tan; Zhengyuan, Li; Pálinkás, Vojtech; Kostelecký, Jakub; Mäkinen, Jaakko; Näränen, Jyri; Merlet, Sébastien; Farah, Tristan; Guerlin, Christine; Pereira Dos Santos, Franck; Le Moigne, Nicolas; Champollion, Cédric; Deville, Sabrina; Timmen, Ludger; Falk, Reinhard; Wilmes, Herbert; Iacovone, Domenico; Baccaro, Francesco; Germak, Alessandro; Biolcati, Emanuele; Krynski, Jan; Sekowski, Marcin; Olszak, Tomasz; Pachuta, Andrzej; Agren, Jonas; Engfeldt, Andreas; Reudink, René; Inacio, Pedro; McLaughlin, Daniel; Shannon, Geoff; Eckl, Marc; Wilkins, Tim; van Westrum, Derek; Billson, Ryan

    2012-01-01

    During November 2011 a EURAMET key comparison of absolute gravimeters was organized in the Underground Laboratory for Geodynamics in Walferdange, Luxemburg. The comparison assembled 22 participants coming from 16 countries and four different continents. The comparison was divided into two parts: a key comparison that included six National Metrology Institutes or Designated Institutes, and a pilot study including all participants. The global result given by the pilot study confirms that all instruments are absolutely coherent with each other. The results obtained in the key comparison confirm a good agreement between the NMI instruments. Finally, a link to ICAG-2009 shows also that the NMI gravimeters are stable in time. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  7. International comparison CCQM-K101: oxygen in nitrogen—a track B comparison and that the matrix contains argon

    NASA Astrophysics Data System (ADS)

    Zhou, Z.; Han, Q.; Wang, D.; Macé, T.; Kipphardt, H.; Maiwald, M.; Tuma, D.; Uehara, S.; Akima, D.; Shimosaka, T.; Jung, J.; Oh, S.-H.; van der Veen, A.; van Wijk, J. I. T.; Ziel, P. R.; Konopelko, L.; Valkova, M.; Mogale, David M.; Botha, A.; Brewer, P.; Murugan, A.; Doval Minnaro, M.; Miller, M.; Guenther, F.; Kelly, M. E.

    2016-01-01

    This key comparison aims to assess the capabilities of the participants to determine the amount-of-substance fraction oxygen in nitrogen. The GAWG has classified this as a track B comparison, due to the unexpected 50 μmol/mol argon mole fraction content of the transfer standards, which effects the achievable performance of some measurement techniques such a GC-TCD. The separation of oxygen and argon is challenging, and not all systems in use are equally well designed for it. As this analytical challenge due to a substantial fraction of argon in the transfer standards became a reality, the Gas Analysis Working Group (GAWG) decided to qualify this key comparison as a regular key comparison and not as a core comparison, which may be used to support calibration and measurement capabilities (CMCs) for oxygen in nitrogen, or for oxygen in nitrogen mixtures containing argon only (see also the section on support to CMCs). Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  8. PWC - PAIRWISE COMPARISON SOFTWARE: SOFTWARE PROGRAM FOR PAIRWISE COMPARISON TASK FOR PSYCHOMETRIC SCALING AND COGNITIVE RESEARCH

    NASA Technical Reports Server (NTRS)

    Ricks, W. R.

    1994-01-01

    PWC is used for pair-wise comparisons in both psychometric scaling techniques and cognitive research. The cognitive tasks and processes of a human operator of automated systems are now prominent considerations when defining system requirements. Recent developments in cognitive research have emphasized the potential utility of psychometric scaling techniques, such as multidimensional scaling, for representing human knowledge and cognitive processing structures. Such techniques involve collecting measurements of stimulus-relatedness from human observers. When data are analyzed using this scaling approach, an n-dimensional representation of the stimuli is produced. This resulting representation is said to describe the subject's cognitive or perceptual view of the stimuli. PWC applies one of the many techniques commonly used to acquire the data necessary for these types of analyses: pair-wise comparisons. PWC administers the task, collects the data from the test subject, and formats the data for analysis. It therefore addresses many of the limitations of the traditional "pen-and-paper" methods. By automating the data collection process, subjects are prevented from going back to check previous responses, the possibility of erroneous data transfer is eliminated, and the burden of the administration and taking of the test is eased. By using randomization, PWC ensures that subjects see the stimuli pairs presented in random order, and that each subject sees pairs in a different random order. PWC is written in Turbo Pascal v6.0 for IBM PC compatible computers running MS-DOS. The program has also been successfully compiled with Turbo Pascal v7.0. A sample executable is provided. PWC requires 30K of RAM for execution. The standard distribution medium for this program is a 5.25 inch 360K MS-DOS format diskette. Two electronic versions of the documentation are included on the diskette: one in ASCII format and one in MS Word for Windows format. PWC was developed in 1993.

  9. New York State 2009 NHTS Comparison Report

    SciTech Connect

    Southworth, Frank; Reuscher, Tim; Hwang, Ho-Ling

    2012-06-01

    The U.S. Department of Transportation (USDOT) initiated an effort in 1969 to collect detailed data on personal travel, with the most recent surveys being the 1995 Nationwide Personal Transportation Survey (NPTS) and the 2001 and 2009 National Household Travel Surveys (NHTS). The primary objective of these surveys is to collect trip-based data on the nature and characteristics of personal travel so that the relationships between the characteristics of personal travel and the socio-economic and demographic characteristics of the traveler and his/her household can be established. In addition to the number of sample households that the national NPTS/NHTS survey allotted to New York State, NYDOT procured an additional sample of households in the 1995, 2001, and 2009 surveys. The comparisons drawn in this report compare the results from these NYS sampled households to the results from households drawn for the rest of the nation. Many of the differences between NYC counties and others in the state result from the striking differences in private vehicle ownership levels, with less than one in two NYC drivers and only 64% of NYC households owning a vehicle in 2009: versus 9 out of 10 drivers owning a vehicle, and between 1.5 and 2 vehicles owned per household, on the average, in the state's other metro areas. And this situation has changed very little over the past fourteen years covered by the three latest NPTS/NHTS surveys. While households in metro areas outside NYC do not own a vehicle largely due to income constraints, many households in NYC/Manhattan do not own a vehicle by choice. However, the statistics suggest that the mobility of zero-vehicle households in NYC/Manhattan is by no means deterred by the lack of a vehicle. While the private vehicle tripmaking rate of NYC residents was between one half and one third that in the state's other metro areas, and their daily VMT about half that of other metro areas, most of their daily travel needs were met by walking or by

  10. Current Comparison of Advanced Fuel Cycle Options

    SciTech Connect

    Steven J. Piet; B. W. Dixon; A. Goldmann; R. N. Hill; J. J. Jacobson; G. E. Matthern; J. D. Smith; A. M. Yacout

    2006-03-01

    The nuclear fuel cycle includes mining, enrichment, nuclear power plants, recycling (if done), and residual waste disposition. The U.S. Advanced Fuel Cycle Initiative (AFCI) has four program objectives to guide research on how best to glue these pieces together, as follows: waste management, proliferation resistance, energy recovery, and systematic management/economics/safety. We have developed a comprehensive set of metrics to evaluate fuel cycle options against the four program objectives. The current list of metrics is long-term heat, long-term dose, radiotoxicity and weapons usable material. This paper describes the current metrics and initial results from comparisons made using these metrics. The data presented were developed using a combination of “static” calculations and a system dynamic model, DYMOND. In many cases, we examine the same issue both dynamically and statically to determine the robustness of the observations. All analyses are for the U.S. reactor fleet. This work aims to clarify many of the issues being discussed within the AFCI program, including Inert Matrix Fuel (IMF) versus Mixed Oxide (MOX) fuel, single-pass versus multi-pass recycling, thermal versus fast reactors, and the value of separating cesium and strontium. The results from a series of dynamic simulations evaluating these options are included in this report. The model interface includes a few “control knobs” for flying or piloting the fuel cycle system into the future. The results from the simulations show that the future is dark (uncertain) and that the system is sluggish with slow time response times to changes (i.e., what types of reactors are built, what types of fuels are used, and the capacity of separation and fabrication plants). Piloting responsibilities are distributed among utilities, government, and regulators, compounding the challenge of making the entire system work and respond to changing circumstances. We identify four approaches that would increase our

  11. Aerosol Angstrom Absorption Coefficient Comparisons during MILAGRO.

    NASA Astrophysics Data System (ADS)

    Marley, N. A.; Marchany-Rivera, A.; Kelley, K. L.; Mangu, A.; Gaffney, J. S.

    2007-12-01

    Measurements of aerosol absorption were obtained as part of the MAX-Mex component of the MILAGRO field campaign at site T0 (Instituto Mexicano de Petroleo in Mexico City) by using a 7-channel aethalometer (Thermo- Anderson) during the month of March, 2006. The absorption measurements obtained in the field at 370, 470, 520, 590, 660, 880, and 950 nm were used to determine the aerosol Angstrom absorption exponents by linear regression. Since, unlike other absorbing aerosol species (e.g. humic like substances, nitrated PAHs), black carbon absorption is relatively constant from the ultraviolet to the infrared with an Angstrom absorption exponent of -1 (1), a comparison of the Angstrom exponents can indicate the presence of aerosol components with an enhanced UV absorption over that expected from BC content alone. The Angstrom exponents determined from the aerosol absorption measurements obtained in the field varied from - 0.7 to - 1.3 during the study and was generally lower in the afternoon than the morning hours, indicating an increase in secondary aerosol formation and photochemically generated UV absorbing species in the afternoon. Twelve-hour integrated samples of fine atmospheric aerosols (<0.1micron) were also collected at site T0 and T1 (Universidad Technologica de Tecamac, State of Mexico) from 5 am to 5 pm (day) and from 5 pm to 5 am (night) during the month of March 2006. Samples were collected on quartz fiber filters with high volume impactor samplers. Continuous absorption spectra of these aerosol samples have been obtained in the laboratory from 280 to 900nm with the use of an integrating sphere coupled to a UV spectrometer (Beckman DU with a Labsphere accessory). The integrating sphere allows the detector to collect and spatially integrate the total radiant flux reflected from the sample and therefore allows for the measurement of absorption on highly reflective or diffusely scattering samples. These continuous spectra have also been used to obtain the

  12. COMPARISON FRICTION: EXPERIMENTAL EVIDENCE FROM MEDICARE DRUG PLANS*

    PubMed Central

    Kling, Jeffrey R.; Mullainathan, Sendhil; Shafir, Eldar; Vermeulen, Lee; Wrobel, Marian V.

    2011-01-01

    Consumers need information to compare alternatives for markets to function efficiently. Recognizing this, public policies often pair competition with easy access to comparative information. The implicit assumption is that comparison friction—the wedge between the availability of comparative information and consumers’ use of it—is inconsequential because information is readily available and consumers will access this information and make effective choices. We examine the extent of comparison friction in the market for Medicare Part D prescription drug plans in the United States. In a randomized field experiment, an intervention group received a letter with personalized cost information. That information was readily available for free and widely advertised. However, this additional step—providing the information rather than having consumers actively access it—had an impact. Plan switching was 28 percent in the intervention group, versus 17 percent in the comparison group, and the intervention caused an average decline in predicted consumer cost of about $100 per year among letter recipients—roughly 5 percent of the cost in the comparison group. Our results suggest that comparison friction can be large even when the cost of acquiring information is small, and may be relevant for a wide range of public policies that incorporate consumer choice. PMID:22454838

  13. 2D/3D image (facial) comparison using camera matching.

    PubMed

    Goos, Mirelle I M; Alberink, Ivo B; Ruifrok, Arnout C C

    2006-11-10

    A problem in forensic facial comparison of images of perpetrators and suspects is that distances between fixed anatomical points in the face, which form a good starting point for objective, anthropometric comparison, vary strongly according to the position and orientation of the camera. In case of a cooperating suspect, a 3D image may be taken using e.g. a laser scanning device. By projecting the 3D image onto a 2D image with the suspect's head in the same pose as that of the perpetrator, using the same focal length and pixel aspect ratio, numerical comparison of (ratios of) distances between fixed points becomes feasible. An experiment was performed in which, starting from two 3D scans and one 2D image of two colleagues, male and female, and using seven fixed anatomical locations in the face, comparisons were made for the matching and non-matching case. Using this method, the non-matching pair cannot be distinguished from the matching pair of faces. Facial expression and resolution of images were all more or less optimal, and the results of the study are not encouraging for the use of anthropometric arguments in the identification process. More research needs to be done though on larger sets of facial comparisons. PMID:16337353

  14. Multiple comparisons for survival data with propensity score adjustment

    PubMed Central

    Zhu, Hong; Lu, Bo

    2015-01-01

    This article considers the practical problem in clinical and observational studies where multiple treatment or prognostic groups are compared and the observed survival data are subject to right censoring. Two possible formulations of multiple comparisons are suggested. Multiple Comparisons with a Control (MCC) compare every other group to a control group with respect to survival outcomes, for determining which groups are associated with lower risk than the control. Multiple Comparisons with the Best (MCB) compare each group to the truly minimum risk group and identify the groups that are either with the minimum risk or the practically minimum risk. To make a causal statement, potential confounding effects need to be adjusted in the comparisons. Propensity score based adjustment is popular in causal inference and can effectively reduce the confounding bias. Based on a propensity-score-stratified Cox proportional hazards model, the approaches of MCC test and MCB simultaneous confidence intervals for general linear models with normal error outcome are extended to survival outcome. This paper specifies the assumptions for causal inference on survival outcomes within a potential outcome framework, develops testing procedures for multiple comparisons and provides simultaneous confidence intervals. The proposed methods are applied to two real data sets from cancer studies for illustration, and a simulation study is also presented. PMID:25663729

  15. Application of Paired-Comparison Methods to Hearing Aids

    PubMed Central

    Amlani, Amyn M.; Schafer, Erin C.

    2009-01-01

    The method of paired comparisons was introduced into the hearing aid literature nearly 50 years ago. Over time, studies have found paired comparisons to be sensitive, valid, and reliable in determining either the perceptual difference or relative ranking among hearing aids and electroacoustic characteristics. With the increasing number of adjustable electroacoustic parameters in today's digital hearing aids—and the lack of procedural guidelines necessary to fit many of them—the method of paired comparisons provides the clinician with the ability to compare different devices, electroacoustic characteristics, memory settings, or combinations of these variables under the listener's everyday listening conditions. Furthermore, this procedure provides the clinician with the ability to individualize the prescriptive approach—which is predicated mainly on hearing threshold data and listening in quiet—so that a combination of parameters can be set to optimize the user's listening needs in a given environment. In this article, the authors present an overview of the theoretical principle supporting this procedure, the various paired-comparison strategies and associated approaches, the advantages of this method, and recommended procedures for implementing the method of paired comparisons in the fitting of today's sophisticated hearing aids. PMID:20150188

  16. Comparison of Meteorological Service Calibration Laboratories in Southeastern Europe

    NASA Astrophysics Data System (ADS)

    Groselj, D.; Bojkovski, J.

    2012-09-01

    Interlaboratory comparisons serve as tools for assessment of measurement results performed by calibration laboratories in the relevant field of measurement. They are effective means to demonstrate technical competence of the participant and are used as a technical base for accreditation. However, in the network of meteorological services calibration laboratories, comparisons among laboratories are still rare. Some laboratories are still not evaluating measurement uncertainty, thus causing problems when comparing meteorological data from different countries. The Environmental Agency of the Republic of Slovenia (EARS), serving in the frame of the World Meteorological Organization as a Regional Instrument Centre, has organized a round-robin comparison of calibration laboratories of meteorological services in the southeastern part of Europe using instruments for temperature, relative humidity, and barometric pressure. Each participant laboratory had to calibrate a set of instruments at defined calibration points, to evaluate the measurement uncertainty (if possible), and to report the results. EARS RIC invited the National Hydrometeorological Services in the southeastern part of Europe to take part in the intercomparison. In addition, the Laboratory of Metrology and Quality (MIRS/UL-FE/LMK), which holds the Slovenian national standard for temperature and relative humidity, was also invited to participate in the comparison and in the data analysis. Results from MIRS/UL-FE/LMK and EARS were used to calculate the temperature and humidity comparison reference values, while the EARS results were taken as reference values for barometric pressure.

  17. International Pyroheliometer Comparison 2010 Results from SORCE/TIM

    NASA Astrophysics Data System (ADS)

    Heuerman, K.; Kopp, G.; Harber, D.

    2010-12-01

    The Eleventh International Pyrheliometer Comparison (IPC-XI), organized by the World Radiation Center (WRC) on behalf of the World Meteorological Organization (WMO), was held 27 September - 15 October 2010 at the Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC) in Davos Dorf, Switzerland with nearly 100 participants representing approximately 60 countries. This ground-based comparison, held every 5 years, has established a multi-decadal baseline record of solar measurement inter-comparisons with which solar radiometers can be linked to the WRC-maintained World Radiation Reference (WRR) and compared to other current and historical radiometers across the IPC’s multi-decadal time range. A ground-based SOlar Radiation and Climate Experiment (SORCE) Total Irradiance Monitor (TIM) participated in the IPC this year, indirectly linking the on-orbit total solar irradiance (TSI) measurements that NASA’s SORCE mission has been acquiring since 2003 with the IPC record. We report the results of this 3-week inter-comparison and estimate the corrections needed and uncertainties introduced in linking these ground-based relative comparisons to the spaceborne TSI data record.

  18. Comparison friction: experimental evidence from medicare drug plans.

    PubMed

    Kling, Jeffrey R; Mullainathan, Sendhil; Shafir, Eldar; Vermeulen, Lee C; Wrobel, Marian V

    2012-01-01

    Consumers need information to compare alternatives for markets to function efficiently. Recognizing this, public policies often pair competition with easy access to comparative information. The implicit assumption is that comparison friction—the wedge between the availability of comparative information and consumers' use of it—is inconsequential because when information is readily available, consumers will access this information and make effective choices. We examine the extent of comparison friction in the market for Medicare Part D prescription drug plans in the United States. In a randomized field experiment, an intervention group received a letter with personalized cost information. That information was readily available for free and widely advertised. However, this additional step—providing the information rather than having consumers actively access it—had an impact. Plan switching was 28% in the intervention group, versus 17% in the comparison group, and the intervention caused an average decline in predicted consumer cost of about $100 a year among letter recipients—roughly 5% of the cost in the comparison group. Our results suggest that comparison friction can be large even when the cost of acquiring information is small and may be relevant for a wide range of public policies that incorporate consumer choice. PMID:22454838

  19. Comparison of density determination of liquid samples by density meters

    NASA Astrophysics Data System (ADS)

    Vámossy, C.; Davidson, S.; Zelenka, Z.

    2016-01-01

    This project was a European regional bilateral comparison of volume determination of stainless steel standards of 10 g, 20 g, and 200 g and 1 kg carried out under the auspices of EURAMET (project 1356, EURAMET.M.D-S3). The objectives of the present comparison were to check the measurement capabilities of the participants in the field of volume measurements of weights and provide a basis for the calibration measurement capabilities (CMC). BEV (Austria) was the pilot laboratory and the provider of the transfer standards. MKEH was the other participant in the bilateral comparison and NPL collected the measurement data ensuring the impartiality. The objectives of the comparison were achieved. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  20. Report on APMP supplementary comparison: high precision roundness measurement

    NASA Astrophysics Data System (ADS)

    Buajarern, J.; Naoi, K.; Baker, A.; Zi, X.; Tsai, C.-L.; Eom, T. B.; Leng, T. S.; Kruger, O.

    2016-01-01

    A regional supplementary comparison, APMP.L-S4, was held in 2012 to demonstrate the equivalence of routine calibration services offered by NMIs to clients. Participants in this APMP.L-S4 comparison agreed to apply multi-step method for spidle error separation in order to yield the high precision roundness measurement. Eight laboratories from NMIs participated in this supplementary comparison; NIMT, NMIJ, NMIA, NIM, CMS/ITRI, KRISS, NMC/A*STAR and NMISA. This report describes the measurement results of 2 glass hemispheres and 2 softgauges. The calibrations of this comparison were carried out by participants during the period from March 2012 to May 2013. The results show that there is a degree of equivalence within 0.8 for all measurands. Hence, there is a close agreement between the measurements. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  1. Artificial bias typically neglected in comparisons of uncertain atmospheric data

    NASA Astrophysics Data System (ADS)

    Pitkänen, Mikko R. A.; Mikkonen, Santtu; Lehtinen, Kari E. J.; Lipponen, Antti; Arola, Antti

    2016-09-01

    Publications in atmospheric sciences typically neglect biases caused by regression dilution (bias of the ordinary least squares line fitting) and regression to the mean (RTM) in comparisons of uncertain data. We use synthetic observations mimicking real atmospheric data to demonstrate how the biases arise from random data uncertainties of measurements, model output, or satellite retrieval products. Further, we provide examples of typical methods of data comparisons that have a tendency to pronounce the biases. The results show, that data uncertainties can significantly bias data comparisons due to regression dilution and RTM, a fact that is known in statistics but disregarded in atmospheric sciences. Thus, we argue that often these biases are widely regarded as measurement or modeling errors, for instance, while they in fact are artificial. It is essential that atmospheric and geoscience communities become aware of and consider these features in research.

  2. The NIH Toolbox Pattern Comparison Processing Speed Test: Normative Data.

    PubMed

    Carlozzi, Noelle E; Beaumont, Jennifer L; Tulsky, David S; Gershon, Richard C

    2015-08-01

    The NIH Toolbox Pattern Comparison Processing Speed Test was developed to assess processing speed. While initial validation work provides preliminary support for this test in both children and adults, more work is needed to ensure dependability and generalizability. Thus, this replication study examines descriptive data (including age effects), test-retest reliability, and construct validity in n = 4,859 participants ages 3-85 years (matched to 2010 census data). Although the Pattern Comparison was not appropriate for all 3 and 4 years old, by ages 5 and 6, more meaningful scores were apparent. There was evidence for convergent and discriminant validity. There was also a moderate practice effect (i.e., increase of 5.5 points) over a 1-week time frame. Pattern Comparison exhibits a number of strengths: it is appropriate for use across the lifespan (ages 5-85), it is short and easy to administer, and there is support for construct validity. PMID:26025230

  3. Facilitating comparisons between ICESat waveforms and ICESat-2 point data

    NASA Astrophysics Data System (ADS)

    Grigsby, S.; Freeman, S.; Abdalati, W.

    2015-12-01

    A major challenge for ICESat-2 is how to make meaningful comparisons between the photon counting point data and legacy ICESat waveforms. Such comparisons are essential in quantifying changes in ice sheets across the last decade, but are complicated by the disparate data that is produced by the two instruments. These comparisons are especially important over complex surfaces such as crevasses, which are among the most dynamic ice sheet features and are often indicative of underlying changes in the ice stress fields. We use a density based algorithm (Ordering Points To Identify the Clustering Structure, or OPTICS) to filter photon counting data from two separate Photon-counting LiDAR instruments; the filtered point data is then weighted and convolved to simulate ICESat waveforms. Linking ICESat waveforms with ICESat-2 photon counts is needed in order to understand changes in ice sheet dynamics, and will help quantify the temporal scale of changes occurring in Greenland's outlet glaciers.

  4. The NIH Toolbox Pattern Comparison Processing Speed Test: Normative Data

    PubMed Central

    Carlozzi, Noelle E.; Beaumont, Jennifer L.; Tulsky, David S.; Gershon, Richard C.

    2015-01-01

    The NIH Toolbox Pattern Comparison Processing Speed Test was developed to assess processing speed. While initial validation work provides preliminary support for this test in both children and adults, more work is needed to ensure dependability and generalizability. Thus, this replication study examines descriptive data (including age effects), test–retest reliability, and construct validity in n = 4,859 participants ages 3–85 years (matched to 2010 census data). Although the Pattern Comparison was not appropriate for all 3 and 4 years old, by ages 5 and 6, more meaningful scores were apparent. There was evidence for convergent and discriminant validity. There was also a moderate practice effect (i.e., increase of 5.5 points) over a 1-week time frame. Pattern Comparison exhibits a number of strengths: it is appropriate for use across the lifespan (ages 5–85), it is short and easy to administer, and there is support for construct validity. PMID:26025230

  5. cocor: a comprehensive solution for the statistical comparison of correlations.

    PubMed

    Diedenhofen, Birk; Musch, Jochen

    2015-01-01

    A valid comparison of the magnitude of two correlations requires researchers to directly contrast the correlations using an appropriate statistical test. In many popular statistics packages, however, tests for the significance of the difference between correlations are missing. To close this gap, we introduce cocor, a free software package for the R programming language. The cocor package covers a broad range of tests including the comparisons of independent and dependent correlations with either overlapping or nonoverlapping variables. The package also includes an implementation of Zou's confidence interval for all of these comparisons. The platform independent cocor package enhances the R statistical computing environment and is available for scripting. Two different graphical user interfaces-a plugin for RKWard and a web interface-make cocor a convenient and user-friendly tool. PMID:25835001

  6. Comparison between the performance of two classes of fuzzy controllers

    NASA Technical Reports Server (NTRS)

    Janabi, T. H.; Sultan, L. H.

    1992-01-01

    This paper presents an application comparison between two classes of fuzzy controllers: the Clearness Transformation Fuzzy Controller (CTFC) and the CRI-based Fuzzy Controller. The comparison is performed by studying the application of the controllers to simulation examples of nonlinear systems. The CTFC is a new approach for the organization of fuzzy controllers based on a cognitive model of parameter driven control, the notion of fuzzy patterns to represent fuzzy knowledge and the Clearness Transformation Rule of Inference (CTRI) for approximate reasoning. The approach facilitates the implementation of the basic modules of the controller: the fuzzifier, defuzzifier, and the control protocol in a rule-based architecture. The CTRI scheme for approximate reasoning does not require the formation of fuzzy relation matrices yielding improved performance in comparison with the traditional organization of fuzzy controllers.

  7. Comparison of immunoturbidimetric and immunonephelometric assays for specific proteins.

    PubMed

    Mali, Bahera; Armbruster, David; Serediak, Ernie; Ottenbreit, Tammy

    2009-10-01

    Immunoturbidimetric assays for specific proteins are available on "open system" clinical chemistry analyzers. The analytical performance of nine immunoturbidimetric specific protein assays (C3, C4, CRP, Haptoglobin, IgA, IgG, IgM, RF, and Transferrin) was compared to immunonephelometry. Testing was performed on the Abbott ARCHITECT ci8200 and the Dade Behring BNII nephelometer and evaluated for precision, linearity, limit of detection, prozone phenomenon, method comparison, workflow, and proficiency testing survey comparison. Immunoturbidimetric assays performance was satisfactory for total precision, linearity, limit of detection and the prozone effect was not observed. Method comparison was acceptable for the immunoglobulins, CRP and transferrin but less favorable for the other assays, likely due to methodology and antibody specificity differences. Immunourbidimetric specific protein assays allow for efficient test consolidation on a general purpose clinical chemistry analyzer.

  8. Price comparisons on the internet based on computational intelligence.

    PubMed

    Kim, Jun Woo; Ha, Sung Ho

    2014-01-01

    Information-intensive Web services such as price comparison sites have recently been gaining popularity. However, most users including novice shoppers have difficulty in browsing such sites because of the massive amount of information gathered and the uncertainty surrounding Web environments. Even conventional price comparison sites face various problems, which suggests the necessity of a new approach to address these problems. Therefore, for this study, an intelligent product search system was developed that enables price comparisons for online shoppers in a more effective manner. In particular, the developed system adopts linguistic price ratings based on fuzzy logic to accommodate user-defined price ranges, and personalizes product recommendations based on linguistic product clusters, which help online shoppers find desired items in a convenient manner.

  9. Report on APMP key comparison: calibration of angle standards

    NASA Astrophysics Data System (ADS)

    Kang, C.-S.; Kruger, O. A.; Cox, P.; Xue, Z.; Liou, P.; Wong, S. Y.; Chaudhary, K. P.; Alfiyati, N.; Watanabe, T.; Eom, T.; Halim, R. M.; Tan, S. L.; Tonmueanwai, A.; Dibo, M.

    2016-01-01

    A regional key comparison, APMP.L-K3 (calibration of angle standards) was held in 2005. Thirteen National Metrology Institutes (NMISA, NMIA, KRISS, NMIJ/ AIST, NMC/ A*STAR, NIMT, SCL, CMS/ ITRI, NPLI, RCM- LIPI, NIM, and NSCL) have participated in this comparison and the measurements were carried out during the period from April 2005 to December 2007. This report describes the measurement results of a 12-sided optical polygon with nominal angles of 30°, and four angle blocks with nominal angles of 5 arc seconds, 5 minutes, 30 minutes and 5 degrees, respectively. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  10. A comparison of hypersonic vehicle flight and prediction results

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.; Shafer, Mary F.

    1995-01-01

    Aerodynamic and aerothermodynamic comparisons between flight and ground test for four hypersonic vehicles are discussed. The four vehicles are the X-15, the Reentry F, the Sandia Energetic Reentry Vehicle Experiment (SWERVE), and the Space Shuttle. The comparisons are taken from papers published by researchers active in the various programs. Aerodynamic comparisons include reaction control jet interaction on the Space Shuttle. Various forms of heating including catalytic, boundary layer, shock interaction and interference, and vortex impingement are compared. Predictions were significantly exceeded for the heating caused by vortex impingement (on the Space Shuttle OMS pods) and for heating caused by shock interaction and interference on the X-15 and the Space Shuttle. Predictions of boundary-layer state were in error on the X-15, the SWERVE, and the Space Shuttle vehicles.

  11. Price Comparisons on the Internet Based on Computational Intelligence

    PubMed Central

    Kim, Jun Woo; Ha, Sung Ho

    2014-01-01

    Information-intensive Web services such as price comparison sites have recently been gaining popularity. However, most users including novice shoppers have difficulty in browsing such sites because of the massive amount of information gathered and the uncertainty surrounding Web environments. Even conventional price comparison sites face various problems, which suggests the necessity of a new approach to address these problems. Therefore, for this study, an intelligent product search system was developed that enables price comparisons for online shoppers in a more effective manner. In particular, the developed system adopts linguistic price ratings based on fuzzy logic to accommodate user-defined price ranges, and personalizes product recommendations based on linguistic product clusters, which help online shoppers find desired items in a convenient manner. PMID:25268901

  12. Comparison of the NIST and ENEA air kerma standards

    SciTech Connect

    Laitano, R.F.; Toni, M.P.; Lamperti, P.J.

    1998-07-01

    A comparison was made between the National Institute of Standards and Technology (NIST) and Ente per le Nuov Tecnologie l`Energia e l`Ambiente (ENEA) air kerma standards for medium energy x rays and {sup 60}Co gamma rays. The comparison took place at ENEA in June 1994. Two different transfer chambers from NIST were used for the comparison. The measurements were made at radiation qualities similar to those used at the Bureau International des Poids et Mesures (BIPM) (generating voltages of 100 kV, 135 kV, 180 kV and 250 kV, respectively) and with {sup 60}Co gamma radiation. The transfer chamber calibration factors obtained at the NIST and at the ENEA agreed with one another to 0.03% for {sup 60}Co gamma radiation and between 0.1% to 0.8% for the medium energy x-ray beam codes.

  13. Process comparison study. MSFC Center Director's Discretionary Fund (CDDF)

    NASA Technical Reports Server (NTRS)

    Golden, T.; Krawiec, J.

    1992-01-01

    A process comparison study was conducted using four different advanced manufacturing techniques to fabricate a composite solid rocket booster systems tunnel cover. Costs and labor hours were tracked to provide the comparison between the processes. A relative structural comparison of the components is also included. The processes utilized included filament winding, pultrusion, automated tape laying, and thermoplastic thermoforming. The hand layup technique is also compared. Of the four advanced processes evaluated, the thermoformed thermoplastic component resulted in the least total cost. The automated tape laying and filament winding techniques closely followed the thermoplastic component in terms of total cost; and, these techniques show the most promise for high quality components and lower production costs. The pultruded component, with its expensive tooling and material requirements, was by far the most expensive process evaluated, although the results obtained would not be representative of large production runs.

  14. Computational methods for protein sequence comparison and search.

    PubMed

    Xu, Dong

    2009-04-01

    Protein sequence comparison and search has become commonplace not only for bioinformatics researchers but also for experimentalists in many cases. Because of the exponential growth in sequence data, sequence comparison in particular has become an increasingly important tool. Relating a new gene sequence to other known sequences often reveals its function, structure, and evolution. Many sequence comparison and search tools are available through public Web servers, and biologists can use them easily with little knowledge of computers or bioinformatics. This unit provides some theoretical background and describes popular tools for dot plot, sequence search against a database, multiple sequence alignments, protein tree construction, and protein family and motif search. Step-by-step examples are provided to illustrate how to use some of the most well-known tools. Finally, some general advice is given on combining different sequence analysis tools for biological inference.

  15. A comparison of hypersonic flight and prediction results

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.; Shafer, Mary F.

    1993-01-01

    Aerodynamic and aerothermodynamic comparisons between flight and ground test for four hypersonic vehicles are discussed. The four vehicles are the X-15, the Reentry F, the Sandia Energetic Reentry Vehicle Experiment (SWERVE), and the Space Shuttle. The comparisons are taken from papers published by researchers active in the various programs. Aerodynamic comparisons include reaction control jet interaction on the Space Shuttle. Various forms of heating including catalytic, boundary layer, shock interaction and interference, and vortex impingement are compared. Predictions were significantly exceeded for the heating caused by vortex impingement (on the Space Shuttle OMS pods) and for heating caused by shock interaction and interference on the X-15 and the Space Shuttle. Predictions of boundary-layer state were in error on the X-15, the SWERVE, and the Space Shuttle vehicles.

  16. SUPPLEMENTARY COMPARISON: COOMET.RI(II)-S1.Rn-222 (169/UA/98): Rn-222 volume activity comparison

    NASA Astrophysics Data System (ADS)

    Skliarov, V.; Röttger, A.; Honig, A.; Korostin, S.; Kuznetsov, S.; Lapenas, A.; Milevsky, V.; Ivaniukovich, A.; Kharitonov, I.; Sepman, S.

    2009-01-01

    According to a first program, a supplementary comparison of Rn-222 volume activity was drawn up as a bilateral supplementary comparison between NSC 'Institute of Metrology', Ukraine, and VNIIFTRI, Russia. It took place in March 2005. In April 2005, at the 5th meeting of COOMET held in Braunschweig (Germany), representatives of these institutes exchanged data which showed the comparability of the national standards of Ukraine and Russia for the check points. During the discussion of the procedure some other institutes decided to join the comparison program, which was extended to BelGIM (Belarus), PTB (Germany), VNIIM (Russia) and RMTC (Latvia). The national standards of volume activity of radon-222 were thus calibrated using one standard radon radiometer as the transfer standard. Results are shown in the Final Report of the comparison. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by COOMET, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  17. MODIS comparisons with northeastern Pacific in situ stratocumulus microphysics

    PubMed Central

    Noble, Stephen R.

    2015-01-01

    Abstract Vertical sounding measurements within stratocumuli during two aircraft field campaigns, Marine Stratus/stratocumulus Experiment (MASE) and Physics of Stratocumulus Top (POST), are used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (r e). In situ COT, LWP, and r e were calculated using 5 m vertically averaged droplet probe measurements of complete vertical cloud penetrations. MODIS COT, LWP, and r e 1 km pixels were averaged along these penetrations. COT comparisons in POST showed strong correlations and a near 1:1 relationship. In MASE, comparisons showed strong correlations; however, MODIS COT exceeded in situ COT, likely due to larger temporal differences between MODIS and in situ measurements. LWP comparisons between two cloud probes show good agreement for POST but not MASE, giving confidence to POST data. Both projects provided strong LWP correlations but MODIS exceeded in situ by 14–36%. MODIS in situ r e correlations were strong, but MODIS 2.1 µm r e exceeded in situ r e, which contributed to LWP bias; in POST, MODIS r e was 20–30% greater than in situ r e. Maximum in situ r e near cloud top showed comparisons nearer 1:1. Other MODIS r e bands (3.7 µm and 1.6 µm) showed similar comparisons. Temporal differences between MODIS and in situ measurements, airplane speed differences, and cloud probe artifacts were likely causes of weaker MASE correlations. POST COT comparison was best for temporal differences under 20 min. POST data validate MODIS COT but it also implies a positive MODIS r e bias that propagates to LWP while still capturing variability. PMID:27708990

  18. MODIS comparisons with northeastern Pacific in situ stratocumulus microphysics

    PubMed Central

    Noble, Stephen R.

    2015-01-01

    Abstract Vertical sounding measurements within stratocumuli during two aircraft field campaigns, Marine Stratus/stratocumulus Experiment (MASE) and Physics of Stratocumulus Top (POST), are used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (r e). In situ COT, LWP, and r e were calculated using 5 m vertically averaged droplet probe measurements of complete vertical cloud penetrations. MODIS COT, LWP, and r e 1 km pixels were averaged along these penetrations. COT comparisons in POST showed strong correlations and a near 1:1 relationship. In MASE, comparisons showed strong correlations; however, MODIS COT exceeded in situ COT, likely due to larger temporal differences between MODIS and in situ measurements. LWP comparisons between two cloud probes show good agreement for POST but not MASE, giving confidence to POST data. Both projects provided strong LWP correlations but MODIS exceeded in situ by 14–36%. MODIS in situ r e correlations were strong, but MODIS 2.1 µm r e exceeded in situ r e, which contributed to LWP bias; in POST, MODIS r e was 20–30% greater than in situ r e. Maximum in situ r e near cloud top showed comparisons nearer 1:1. Other MODIS r e bands (3.7 µm and 1.6 µm) showed similar comparisons. Temporal differences between MODIS and in situ measurements, airplane speed differences, and cloud probe artifacts were likely causes of weaker MASE correlations. POST COT comparison was best for temporal differences under 20 min. POST data validate MODIS COT but it also implies a positive MODIS r e bias that propagates to LWP while still capturing variability.

  19. MODIS comparisons with northeastern Pacific in situ stratocumulus microphysics

    NASA Astrophysics Data System (ADS)

    Noble, Stephen R.; Hudson, James G.

    2015-08-01

    Vertical sounding measurements within stratocumuli during two aircraft field campaigns, Marine Stratus/stratocumulus Experiment (MASE) and Physics of Stratocumulus Top (POST), are used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (re). In situ COT, LWP, and re were calculated using 5 m vertically averaged droplet probe measurements of complete vertical cloud penetrations. MODIS COT, LWP, and re 1 km pixels were averaged along these penetrations. COT comparisons in POST showed strong correlations and a near 1:1 relationship. In MASE, comparisons showed strong correlations; however, MODIS COT exceeded in situ COT, likely due to larger temporal differences between MODIS and in situ measurements. LWP comparisons between two cloud probes show good agreement for POST but not MASE, giving confidence to POST data. Both projects provided strong LWP correlations but MODIS exceeded in situ by 14-36%. MODIS in situ re correlations were strong, but MODIS 2.1 µm re exceeded in situ re, which contributed to LWP bias; in POST, MODIS re was 20-30% greater than in situ re. Maximum in situ re near cloud top showed comparisons nearer 1:1. Other MODIS re bands (3.7 µm and 1.6 µm) showed similar comparisons. Temporal differences between MODIS and in situ measurements, airplane speed differences, and cloud probe artifacts were likely causes of weaker MASE correlations. POST COT comparison was best for temporal differences under 20 min. POST data validate MODIS COT but it also implies a positive MODIS re bias that propagates to LWP while still capturing variability.

  20. The Ring total knee replacement--a comparison of survivorship.

    PubMed Central

    Curtis, M J; Bland, J M; Ring, P A

    1992-01-01

    Long term results of joint replacement are frequently expressed as survivorship; it therefore becomes increasingly important to have the ability to make valid comparisons between survivorship tables in order to determine accurately the statistical significance of published differences. We present a statistical method for direct comparison of survivorship tables. We have applied this technique to evaluate the survivorship of the unconstrained, uncemented Ring total knee replacement first implanted in 1975 and compare this to contemporaneous constrained prostheses. There is a significant improvement in survival, which suggests a beneficial long-term effect on the bone/implant interface of this changing design concept. Images Figure 1. PMID:1433061

  1. Estimating neighborhood variability with a binary comparison matrix.

    USGS Publications Warehouse

    Murphy, D.L.

    1985-01-01

    A technique which utilizes a binary comparison matrix has been developed to implement a neighborhood function for a raster format data base. The technique assigns an index value to the center pixel of 3- by 3-pixel neighborhoods. The binary comparison matrix provides additional information not found in two other neighborhood variability statistics; the function is sensitive to both the number of classes within the neighborhood and the frequency of pixel occurrence in each of the classes. Application of the function to a spatial data base from the Kenai National Wildlife Refuge, Alaska, demonstrates 1) the numerical distribution of the index values, and 2) the spatial patterns exhibited by the numerical values. -Author

  2. CCL: an algorithm for the efficient comparison of clusters

    PubMed Central

    Hundt, R.; Schön, J. C.; Neelamraju, S.; Zagorac, J.; Jansen, M.

    2013-01-01

    The systematic comparison of the atomic structure of solids and clusters has become an important task in crystallography, chemistry, physics and materials science, in particular in the context of structure prediction and structure determination of nanomaterials. In this work, an efficient and robust algorithm for the comparison of cluster structures is presented, which is based on the mapping of the point patterns of the two clusters onto each other. This algorithm has been implemented as the module CCL in the structure visualization and analysis program KPLOT. PMID:23682193

  3. Blue Marble Matches: Using Earth for Planetary Comparisons

    NASA Technical Reports Server (NTRS)

    Graff, Paige Valderrama

    2009-01-01

    Goal: This activity is designed to introduce students to geologic processes on Earth and model how scientists use Earth to gain a better understanding of other planetary bodies in the solar system. Objectives: Students will: 1. Identify common descriptor characteristics used by scientists to describe geologic features in images. 2. Identify geologic features and how they form on Earth. 3. Create a list of defining/distinguishing characteristics of geologic features 4. Identify geologic features in images of other planetary bodies. 5. List observations and interpretations about planetary body comparisons. 6. Create summary statements about planetary body comparisons.

  4. Preliminary Comparison of Skin Friction Measurements with CFD Predictions

    NASA Technical Reports Server (NTRS)

    Kennelly, Robert A., Jr.; Lawrence, Scott L.; Flamm, Jeffrey D.

    1999-01-01

    The work to be described was performed at the NASA Langley UPWT (4-ft supersonic), test section #2, during 21-24 May 1996. The configuration being tested was the 1.675% Ref H controls model; test conditions were Ma = 2.40, Re = 3 million/ft. This was an exploration of a new technique, and it was not intended to provide definitive comparison of measured and computed skin friction results. It is, however, hoped that the experience gained will make such a rigorous comparison possible in the future.

  5. Status and solidarity in social comparison: agentic and communal values and vertical and horizontal directions.

    PubMed

    Locke, Kenneth D

    2003-03-01

    Social comparison involves positioning the self relative to others on a vertical or status dimension (ranging from upward to downward comparisons) and a horizontal or solidarity dimension (ranging from contrastive to connective comparisons). Across 3 studies in which 389 undergraduates recorded everyday social comparisons (n = 4,417), downward and connective comparisons were rated as more helpful and mood enhancing than upward and contrastive comparisons. The effects of horizontal comparisons were greater for people for whom solidarity was an important value; however, the effects of vertical comparisons were not greater for people who valued status. The roles of the comparison target, topic, and situation were also explored; for example, noticing undesirable features of the target enhanced status but undermined solidarity. PMID:12635921

  6. [Development of an Excel spreadsheet for meta-analysis of indirect and mixed treatment comparisons].

    PubMed

    Tobías, Aurelio; Catalá-López, Ferrán; Roqué, Marta

    2014-01-01

    Meta-analyses in clinical research usually aimed to evaluate treatment efficacy and safety in direct comparison with a unique comparator. Indirect comparisons, using the Bucher's method, can summarize primary data when information from direct comparisons is limited or nonexistent. Mixed comparisons allow combining estimates from direct and indirect comparisons, increasing statistical power. There is a need for simple applications for meta-analysis of indirect and mixed comparisons. These can easily be conducted using a Microsoft Office Excel spreadsheet. We developed a spreadsheet for indirect and mixed effects comparisons of friendly use for clinical researchers interested in systematic reviews, but non-familiarized with the use of more advanced statistical packages. The use of the proposed Excel spreadsheet for indirect and mixed comparisons can be of great use in clinical epidemiology to extend the knowledge provided by traditional meta-analysis when evidence from direct comparisons is limited or nonexistent.

  7. SUPPLEMENTARY COMPARISON: Negative gauge pressure comparison: range -95 kPa to +95 kPa (EURAMET Project 1131)

    NASA Astrophysics Data System (ADS)

    Rantanen, Markku; Saxholm, Sari; Altintas, Aykurt; Pavis, Richard; Peterson, Guliko

    2010-01-01

    A pressure comparison in the negative gauge pressure range was arranged in 2009. The participating laboratories were CMI/Czech Republic, FORCE Technology/Denmark, AS Metrosert/Estonia and MIKES/Finland. Negative gauge pressures are a common range for pressure calibrations although uncertainty requirements are generally not very high. The results from the four participating laboratories suggest that calibrations in the negative gauge pressure range are not as easy as expected. Some of the claimed uncertainties were perhaps too optimistic, and the large variation in the results made it difficult to generate consistent reference values. The agreement of the results at positive gauge pressures on the same transfer standard was much better. Obviously there is a need for further comparisons in the negative gauge pressure range. The transfer standard was a multifunction calibrator Beamex MC5 equipped with an internal pressure module for the range -100 kPa to 104 kPa in the gauge mode. The resolution of the display was 0.001 kPa. The stability of the transfer standard was good. The comparison was registered as EURAMET Project No. 1131 and as the supplementary comparison EURAMET.M.P-S8 in the BIPM key comparison database. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by EURAMET, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  8. KEY COMPARISON: Final report on key comparison CCQM-K59: Determination of nitrite and nitrate in calibration solutions

    NASA Astrophysics Data System (ADS)

    Máriássy, Michal; Hioki, Akiharu; Konopelko, Leonid A.; Dimchoglo, Irina; Winchester, Michael; Butler, Therese; Case, Ryan; Hernández, Ana; Galli, Ariel; Alvarez, Pablo; Hae Lee, Joung; Royer, Chantal; Shi, Naijie; Chao, Jingbo; Wu, Bing; Li, Haifeng

    2008-01-01

    In this key comparison anion calibration solutions of nitrate and nitrite were investigated. The mass fractions of the anions in both solutions were about 1 g/kg. For the nitrate comparison 8 participants provided results; 3 analytical techniques were used: ion chromatography, capillary electrophoresis and coulometry after ion exchange. The nitrite amount content was determined by 7 participants using one of the following 3 techniques: ion chromatography, titrimetry and capillary electrophoresis. The following institutes participated in this key comparison: INTI (Argentina), KRISS (Korea), LNE (France), NIM (Pepole's Republic of China), NIST (USA), NMIJ (Japan), SMU (Slovakia) and VNIIM (Russia). The variability (RSD) of the results is about 0.75% for both the nitrite and the nitrate solutions. Compared to the key comparison CCQM-K29 the results of CCQM-K59 were significantly worse. This is in part due to the measurement methods used, possibly also due to the standards used by the institutes. A pilot study (P89) was performed in parallel on the same calibration solutions used in this K59 comparison study by laboratories preferring to participate in the pilot study and on a seawater sample containing about 0.1 mg/kg nitrite and 1 mg/kg nitrate. The results of the pilot study are reported separately. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  9. International Comparisons in Education: Curriculum, Values, and Lessons.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Communications Branch.

    This study was intended to promote discussion between business leaders and educators in Alberta (Canada) on the quality of Alberta's education system and its relation to the province's economic competitiveness. The study offers an objective comparison of materials used in grades 7 to 12 to teach mathematics, physics, and chemistry in Japan,…

  10. Rodent nutrition: digestive comparisons of 4 common rodent species.

    PubMed

    Grant, Kerrin

    2014-09-01

    This article summarizes the literature regarding digestive strategies and captive diets of common rodent pocket pets. A comparison is made between the 2 suborders in which chinchillas, guinea pigs, hamsters, and gerbils occur, highlighting digestive anatomy and dietary adaptations. Recommended captive diets are provided, as well as common nutritionally related health issues that may be presented to veterinary clinics.

  11. Student Assessment: A Comparison of Solitary, Cooperative, and Competitive Testing

    ERIC Educational Resources Information Center

    Desrochers, Marcie N.; Fink, Herbert C.; Thomas, Andrea; Kimmerling, Joe; Tung, Wendy

    2007-01-01

    Alternatives to a solitary testing format can involve students working in teams to arrive at the correct answer. We compared two group assessment methods, cooperative and competitive, to a solitary testing approach. In most comparisons examining the undergraduate respondents' (N = 77) performance, the two group-testing methods were equivalent.…

  12. A Comparison of Three Online Information Retrieval Services.

    ERIC Educational Resources Information Center

    Zais, Harriet W.

    Three firms which offer online information retrieval are compared. The firms are Lockheed Information Service, System Development Corporation and the Western Research Application Center. Comparison tables provide information such as hours accessible, coverage, file update, search elements and cost figures for 15 data bases. In addition, general…

  13. Ares 1X Hybrid Modeling with Comparisons to Flight Data

    NASA Technical Reports Server (NTRS)

    Niedermaier, Dan; Kaouk, Mo

    2010-01-01

    This slide presentation reviews the Ares 1X test flight and compares the resultant flight data with the results of modeled data from siumulations of the flight. It includes: (1) Ares 1X Flight Summary, (2) Ares 1X Data Summary (3) Model Descriptions (4) Model Comparisons to Flight Data in three areas: (a) Liftoff, (b) Transonic and (c) Roll Control Firings (RCS) Firings.

  14. Comparison of density determination of liquid samples by density meters

    NASA Astrophysics Data System (ADS)

    Buchner, C.; Wolf, H.; Vámossy, C.; Lorefice, S.; Lenard, E.; Spohr, I.; Mares, G.; Perkin, M.; Parlic-Risovic, T.; Grue, L.-L.; Tammik, K.; van Andel, I.; Zelenka, Z.

    2016-01-01

    Hydrostatic density determinations of liquids as reference material are mainly performed by National Metrology Institutes to provide means for calibrating or checking liquid density measuring instruments such as oscillation-type density meters. These density meters are used by most of the metrology institutes for their calibration and scientific work. The aim of this project was to compare the results of the liquid density determination by oscillating density meters of the participating laboratories. The results were linked to CCM.D.K-2 partly via Project EURAMET.M.D.K-2 (1019) "Comparison of liquid density standards" by hydrostatic weighing piloted by BEV in 2008. In this comparison pentadecane, water and of oil with a high viscosity were measured at atmospheric pressure using oscillation type density meter. The temperature range was from 15 °C to 40 °C. The measurement results were in some cases discrepant. Further studies, comparisons are essential to explore the capability and uncertainty of the density meters Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  15. Arima model and exponential smoothing method: A comparison

    NASA Astrophysics Data System (ADS)

    Wan Ahmad, Wan Kamarul Ariffin; Ahmad, Sabri

    2013-04-01

    This study shows the comparison between Autoregressive Moving Average (ARIMA) model and Exponential Smoothing Method in making a prediction. The comparison is focused on the ability of both methods in making the forecasts with the different number of data sources and the different length of forecasting period. For this purpose, the data from The Price of Crude Palm Oil (RM/tonne), Exchange Rates of Ringgit Malaysia (RM) in comparison to Great Britain Pound (GBP) and also The Price of SMR 20 Rubber Type (cents/kg) with three different time series are used in the comparison process. Then, forecasting accuracy of each model is measured by examinethe prediction error that producedby using Mean Squared Error (MSE), Mean Absolute Percentage Error (MAPE), and Mean Absolute deviation (MAD). The study shows that the ARIMA model can produce a better prediction for the long-term forecasting with limited data sources, butcannot produce a better prediction for time series with a narrow range of one point to another as in the time series for Exchange Rates. On the contrary, Exponential Smoothing Method can produce a better forecasting for Exchange Rates that has a narrow range of one point to another for its time series, while itcannot produce a better prediction for a longer forecasting period.

  16. PACIFIC NORTHWEST SIDE-BY-SIDE PROTOCOL COMPARISON TEST

    EPA Science Inventory

    Eleven state, tribal, and federal agencies participated during summer 2005 in a side-by-side comparison of protocols used to measure common in-stream physical attributes to help determine which protocols are best for determining status and trend of stream/watershed condition. Th...

  17. A Comparison of Three Auditory Discrimination-Perception Tests

    ERIC Educational Resources Information Center

    Koenke, Karl

    1978-01-01

    Comparisons were made between scores of 52 third graders on three measures of auditory discrimination: Wepman's Auditory Discrimination Test, the Goldman-Fristoe Woodcock (GFW) Test of Auditory Discrimination, and the Kimmell-Wahl Screening Test of Auditory Perception (STAP). (CL)

  18. Effects of Perceptual Variations on Number Comparison Tasks.

    ERIC Educational Resources Information Center

    Kingma, Johannes; Loth, Franciska L.

    1984-01-01

    Investigates the performance of 502 children ranging in age from four years to six years, ten months, on two-choice and multiple-choice number comparison tasks, and explores the effects of perceptual manipulations of elements in the multiple-choice tasks. (RH)

  19. 38 CFR 4.120 - Evaluations by comparison.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... gait, tremors, visceral manifestations, injury to the skull, etc. In rating disability from the... FOR RATING DISABILITIES Disability Ratings Neurological Conditions and Convulsive Disorders § 4.120 Evaluations by comparison. Disability in this field is ordinarily to be rated in proportion to the...

  20. A Fiducial Approach to Extremes and Multiple Comparisons

    ERIC Educational Resources Information Center

    Wandler, Damian V.

    2010-01-01

    Generalized fiducial inference is a powerful tool for many difficult problems. Based on an extension of R. A. Fisher's work, we used generalized fiducial inference for two extreme value problems and a multiple comparison procedure. The first extreme value problem is dealing with the generalized Pareto distribution. The generalized Pareto…

  1. Challenges in Using Comparison Data in Child Welfare Evaluations

    ERIC Educational Resources Information Center

    White, Catherine Roller; O'Brien, Kirk; Davis, Cynthia W.; Rogg, Carla; Rudlang-Perman, Kristen; Morgan, Linda Jewell; Houston, Millicent

    2016-01-01

    Objective: This article describes the evaluation of permanency roundtables, an intervention to help youth in foster care achieve legal permanency and the challenges evaluators faced in finding and using appropriate comparison data. Method: In 2009, permanency roundtables were conducted for 496 children in Georgia, most of whom had spent extended…

  2. Efficient Multicriteria Protein Structure Comparison on Modern Processor Architectures

    PubMed Central

    Sharma, Anuj; Manolakos, Elias S.

    2015-01-01

    Fast increasing computational demand for all-to-all protein structures comparison (PSC) is a result of three confounding factors: rapidly expanding structural proteomics databases, high computational complexity of pairwise protein comparison algorithms, and the trend in the domain towards using multiple criteria for protein structures comparison (MCPSC) and combining results. We have developed a software framework that exploits many-core and multicore CPUs to implement efficient parallel MCPSC in modern processors based on three popular PSC methods, namely, TMalign, CE, and USM. We evaluate and compare the performance and efficiency of the two parallel MCPSC implementations using Intel's experimental many-core Single-Chip Cloud Computer (SCC) as well as Intel's Core i7 multicore processor. We show that the 48-core SCC is more efficient than the latest generation Core i7, achieving a speedup factor of 42 (efficiency of 0.9), making many-core processors an exciting emerging technology for large-scale structural proteomics. We compare and contrast the performance of the two processors on several datasets and also show that MCPSC outperforms its component methods in grouping related domains, achieving a high F-measure of 0.91 on the benchmark CK34 dataset. The software implementation for protein structure comparison using the three methods and combined MCPSC, along with the developed underlying rckskel algorithmic skeletons library, is available via GitHub. PMID:26605332

  3. Library Research: A Domain Comparison of Two Library Journals

    ERIC Educational Resources Information Center

    Davies, Karen; Thiele, Jennifer

    2013-01-01

    Research articles published by the "Community & Junior College Libraries" journal and the "College & Undergraduate Libraries" journal were analyzed to determine their domain. The discussion includes a comparison of past domain studies with the current research. The researchers found the majority of articles (52%) in the…

  4. Can Comparison of Contrastive Examples Facilitate Graph Understanding?

    ERIC Educational Resources Information Center

    Smith, Linsey A.; Gentner, Dedre

    2011-01-01

    The authors explore the role of comparison in improving graph fluency. The ability to use graphs fluently is crucial for STEM achievement, but graphs are challenging to interpret and produce because they often involve integration of multiple variables, continuous change in variables over time, and omission of certain details in order to highlight…

  5. Emphases of Parenting in the Light of Three Comparison Groups

    ERIC Educational Resources Information Center

    Laukkanen, Ella; Karppinen, Sanna; Määttä, Kaarina; Uusiautti, Satu

    2014-01-01

    Parenthood is a phenomenon that is not easy to research. This study analyzed the emphases of parenting in the light of three comparison groups. The research was grounded on Bradley's (2007) theory of six fundamental parenting tasks. This was a case study focusing in one second-grade classroom. The teacher, 18 parents, and 19 pupils were recruited…

  6. Laboratory comparisons of acoustic and optical sensors for microbubble measurement

    NASA Technical Reports Server (NTRS)

    Su, Ming Yang; Todoroff, Douglas; Cartmill, John

    1994-01-01

    This paper presents the results of a recent comparison between three microbubble size spectrum measurement systems. These systems are the light-scattering bubble counter, the photographic bubble-imaging system, and the acoustic resonator array. Good agreement was formed among these three systems over the bubble size range appropriate for each system.

  7. A Comparison of Chinese and American Indian (Chumash) Medicine

    PubMed Central

    Garcia, Cecilia; Lien, Eric J.

    2010-01-01

    Chinese and Chumash traditional medical approaches are similar in terms of disease causation, use of acupuncture or healing touch, plants, spiritual and philosophical approaches. This article provides a brief comparison and discussion of Chinese and Chumash traditional medical practices. A table of 66 plants is presented along with Chinese and Chumash uses of each plant. These uses are compared and contrasted. PMID:18955312

  8. Attentional Modulation of Perceptual Comparison for Feature Binding

    ERIC Educational Resources Information Center

    Kuo, Bo-Cheng; Rotshtein, Pia; Yeh, Yei-Yu

    2011-01-01

    We investigated the neural correlates of attentional modulation in the perceptual comparison process for detecting feature-binding changes in an event-related functional magnetic resonance imaging (fMRI) experiment. Participants performed a variant of a cued change detection task. They viewed a memory array, a spatial retro-cue, and later a probe…

  9. FIELD MEASUREMENT OF DISSOLVED OXYGEN: A COMPARISON OF METHODS

    EPA Science Inventory

    The ability to confidently measure the concentration of dissolved oxygen (D.O.) in ground water is a key aspect of remedial selection and assessment. Presented here is a comparison of the commonly practiced methods for determining D.O. concentrations in ground water, including c...

  10. Efficient Multicriteria Protein Structure Comparison on Modern Processor Architectures.

    PubMed

    Sharma, Anuj; Manolakos, Elias S

    2015-01-01

    Fast increasing computational demand for all-to-all protein structures comparison (PSC) is a result of three confounding factors: rapidly expanding structural proteomics databases, high computational complexity of pairwise protein comparison algorithms, and the trend in the domain towards using multiple criteria for protein structures comparison (MCPSC) and combining results. We have developed a software framework that exploits many-core and multicore CPUs to implement efficient parallel MCPSC in modern processors based on three popular PSC methods, namely, TMalign, CE, and USM. We evaluate and compare the performance and efficiency of the two parallel MCPSC implementations using Intel's experimental many-core Single-Chip Cloud Computer (SCC) as well as Intel's Core i7 multicore processor. We show that the 48-core SCC is more efficient than the latest generation Core i7, achieving a speedup factor of 42 (efficiency of 0.9), making many-core processors an exciting emerging technology for large-scale structural proteomics. We compare and contrast the performance of the two processors on several datasets and also show that MCPSC outperforms its component methods in grouping related domains, achieving a high F-measure of 0.91 on the benchmark CK34 dataset. The software implementation for protein structure comparison using the three methods and combined MCPSC, along with the developed underlying rckskel algorithmic skeletons library, is available via GitHub. PMID:26605332

  11. Comparison of Turbulent Thermal Diffusivity and Scalar Variance Models

    NASA Technical Reports Server (NTRS)

    Yoder, Dennis A.

    2016-01-01

    This paper will include a detailed comparison of heat transfer models that rely upon the thermal diffusivity. The goals are to inform users of the development history of the various models and the resulting differences in model formulations, as well as to evaluate the models on a variety of validation cases so that users might better understand which models are more broadly applicable.

  12. The Differing Roles of Comparison and Contrast in Children's Categorization

    ERIC Educational Resources Information Center

    Namy, Laura L.; Clepper, Lauren E.

    2010-01-01

    Comparison of perceptually similar exemplars from an object category encourages children to overlook compelling perceptual similarities and use relational and functional properties more relevant for taxonomic categorization. This article investigates whether showing children a contrasting object that is perceptually similar but out of kind serves…

  13. A Cross-Cultural Comparison of Letters of Recommendation.

    ERIC Educational Resources Information Center

    Precht, Kristen

    1998-01-01

    Distinct regional patterns emerged in a comparison of letters of recommendation from the United States, United Kingdom, Germany, and Eastern Europe. Both quantitative (linearity, symmetry, data integration, advance organizers, sentence types) and qualitative (content) analyses revealed differences, including organizational patterns and methods of…

  14. Teacher Job Satisfaction and Burnout Viewed through Social Comparisons

    ERIC Educational Resources Information Center

    Kitchel, Tracy; Smith, Amy R.; Henry, Anna L.; Robinson, J. Shane; Lawver, Rebecca G.; Park, Travis D.; Schell, Ashley

    2012-01-01

    Understanding job satisfaction, stress, and burnout within agricultural education has the potential to impact the profession's future. Studying these factors through the theoretical lens of social comparison takes a cultural approach by investigating how agriculture teachers interact with and compare themselves to others. The purpose of this study…

  15. 1976-77 Internal Revenue Service Comparison Study. Final Report.

    ERIC Educational Resources Information Center

    Applied Management Sciences, Inc., Silver Spring, MD.

    Application forms for the Basic Educational Opportunity Grant (BEOG) program for 1976-1977 were compared to 1975 tax forms filed with the Internal Revenue Service (IRS). Comparisons were also made to data from a similar 1974-1975 study. Based on a sample of 212,263 applicants, findings include the following: during 1976-1977, 70.7 percent of all…

  16. 1979-80 Internal Revenue Service Comparison Study. Final Report.

    ERIC Educational Resources Information Center

    Applied Management Sciences, Inc., Silver Spring, MD.

    Application forms for the Basic Educational Opportunity Grant (BEOG) program for 1979-1980 were compared to 1978 tax forms filed with the Internal Revenue Service (IRS). Comparisons were also made to data from similar 1974-1975 and 1976-1977 studies. Based on a sample of 407,596 applicants, findings include the following: between 1976-1977 and…

  17. Comparison of drop size distributions from two droplet sizing systems

    NASA Technical Reports Server (NTRS)

    Oldenburg, John R.; Ide, Robert F.

    1990-01-01

    A comparison between the Phase Doppler Particle Analyzer and the combined measurements from Particle Measuring Systems' Forward Scattering Spectrometer Probe and the Optical Array Probe was conducted in an icing wind tunnel using NASA Icing Research Tunnel spray nozzles to produce the supercooled water droplet cloud. Clouds having a range of volume median diameters from 10 to greater than 50 microns were used for the instrument comparisons. A volume median diameter was calculated from combining the droplet distributions of the Optical Array Probe and the Forward Scattering Spectrometer Probe. A comparison of the combined volume median diameters and the Phase Doppler Particle Analyzer volume median diameters showed agreement from 10 microns up to 30 microns. Typical drop size distributions from the Phase Doppler Particle Analyzer, the Forward Scattering Spectrometer Probe, and Optical Array Probe are presented for several median volume diameters. A comparison of the distributions illustrates regions of the distributions where there is good agreement and other regions where there are discrepancies between the Phase Doppler Particle Analyzer and the Particle Measuring Systems' droplet size instruments.

  18. Mathematics Comparison Study = Etude Comporative Portant Sur les Mathematiques.

    ERIC Educational Resources Information Center

    Alberta Dept. of Education, Edmonton. Curriculum Standards Branch.

    At the request of the Council of Ministries of Education, Canada (CMEC), Alberta Learning conducted this Mathematics Comparison Study. The focus of this study is from Kindergarten to Grade 12. All provinces and territories were invited to participate, and only the Quebec region declined. Participating regions were invited to send a representative…

  19. COMPARISON OF THREE METHODS FOR COUNTING HUMAN SPERMATOZOA

    EPA Science Inventory

    COMPARISON OF THREE METHODS FOR COUNTING HUMAN SPERMATOZOA SC Jeffay1, LF Strader1, RA Morris1, JE Schmid1, AF Olshan2, LW Lansdell2, SD Perreault1. 1US EPA/ORD, RTP, NC; 2UNC-CH, Chapel Hill, NC.
    The IDENT feature of the HTM-IVOS semen analyzer (Hamilton Thorne Research, Bev...

  20. Some Advantages of Controlling for False Discoveries in Multiple Comparisons.

    ERIC Educational Resources Information Center

    Williams, Valerie S. L.

    Multiple comparison procedures for controlling familywise Type I error and the false discovery rate are described and compared, including the traditional Bonferroni correction, a sequential (step-up) Bonferroni procedure (Hochberg, 1988), and a sequential false discovery rate procedure proposed by Benjamini and Hochberg (1995). Motivation for…

  1. How Fragile Is Consolidated Knowledge? Ben's Comparisons of Infinite Sets

    ERIC Educational Resources Information Center

    Tsamir, Pessia; Dreyfus, Tommy

    2005-01-01

    This article builds on two previous ones in which we presented the processes of construction and consolidation of one student's knowledge structures about comparisons of infinite sets, according to a recently proposed theory of abstraction. In the present article, we show that under slight variations of context, knowledge structures that have…

  2. 42 CFR 493.1281 - Standard: Comparison of test results.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 5 2013-10-01 2013-10-01 false Standard: Comparison of test results. 493.1281 Section 493.1281 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... following relevant criteria, when available: (1) Patient age. (2) Sex. (3) Diagnosis or pertinent...

  3. 42 CFR 493.1281 - Standard: Comparison of test results.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 5 2014-10-01 2014-10-01 false Standard: Comparison of test results. 493.1281 Section 493.1281 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... following relevant criteria, when available: (1) Patient age. (2) Sex. (3) Diagnosis or pertinent...

  4. 8. Comparison of construction of bottom and top chords and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Comparison of construction of bottom and top chords and pin connections, bottom chord second panel point, top chords showing third panel point. - Bridge No. 2.4, Spanning Boiling Fork Creek at Railroad Milepost JC-2.4, Decherd, Franklin County, TN

  5. Composition, Context, and Endogeneity in School and Teacher Comparisons

    ERIC Educational Resources Information Center

    Castellano, Katherine E.; Rabe-Hesketh, Sophia; Skrondal, Anders

    2014-01-01

    Investigations of the effects of schools (or teachers) on student achievement focus on either (1) individual school effects, such as value-added analyses, or (2) school-type effects, such as comparisons of charter and public schools. Controlling for school composition by including student covariates is critical for valid estimation of either kind…

  6. Comparison of CRBRP standards to DOE prescribed standards

    SciTech Connect

    Ogg, W W; Copeland, G S

    1983-09-02

    The tables list standards committed to by CRBRP in its design documents, its Environmental Report, and its Preliminary Safety Analysis Report. The compilation of these standards has been placed in column form beside the column of prescribed standards listed under the various headings of Chapter 1 of DOE's Order 5480.1A, Environmental Protection, Safety, and Health Protection Program for DOE Operations. (The DOE standards listed, however, include all those in the other applicable chapters of 5480.1A as mandated in Chapter 1.) There are some CRBRP systems which are impacted very little, if any, by the safety requirements of 5480.1A's prescribed standards. The standards committed to in those systems are, consequently, not included in this comparison. The comparison is made in detail, however, for standards committed to in those systems of CRBRP having areas of safety corresponding to DOE's jurisdiction/requirements as opposed to areas covered only by the USNRC's jurisdiction/regulations. Included in this document are: (1) a table listing titles of the standards not already listed in the comparison table, and (2) a list of acronyms. It seems apparent by the comparison that CRBRP meets the DOE requirement that the Project standards be equal or better (more conservative) than DOE's own prescribed standards.

  7. Comparison of large networks with sub-sampling strategies

    NASA Astrophysics Data System (ADS)

    Ali, Waqar; Wegner, Anatol E.; Gaunt, Robert E.; Deane, Charlotte M.; Reinert, Gesine

    2016-07-01

    Networks are routinely used to represent large data sets, making the comparison of networks a tantalizing research question in many areas. Techniques for such analysis vary from simply comparing network summary statistics to sophisticated but computationally expensive alignment-based approaches. Most existing methods either do not generalize well to different types of networks or do not provide a quantitative similarity score between networks. In contrast, alignment-free topology based network similarity scores empower us to analyse large sets of networks containing different types and sizes of data. Netdis is such a score that defines network similarity through the counts of small sub-graphs in the local neighbourhood of all nodes. Here, we introduce a sub-sampling procedure based on neighbourhoods which links naturally with the framework of network comparisons through local neighbourhood comparisons. Our theoretical arguments justify basing the Netdis statistic on a sample of similar-sized neighbourhoods. Our tests on empirical and synthetic datasets indicate that often only 10% of the neighbourhoods of a network suffice for optimal performance, leading to a drastic reduction in computational requirements. The sampling procedure is applicable even when only a small sample of the network is known, and thus provides a novel tool for network comparison of very large and potentially incomplete datasets.

  8. Intensity perception. VIII. Loudness comparisons between different types of stimuli.

    PubMed

    Lim, J S; Rabinowtiz, W M; Braida, L D; Durlach, N I

    1977-11-01

    In this paper, we describe an extension of our preliminary theory of intensity resolution [Durlach and Braida, J. Acoust. Soc. Am. 46, 372-383 (1969)] to include loudness comparisons among different types of stimuli. The extended theory relates mean loudness matches to discrimination and provides a framework for the interpretation of results on the intrasubject variability of loudness comparisons. The predicted relation between mean loudness matches and discrimination is essentially the same as that proposed by Riesz [J. Acoust. Soc. Am. 5, 211-216 (1933)]. With regard to the variability of loudness comparisons, the extended model is essentially the same as the preliminary model except that a new term is included in the trace-mode memory variance to account for the dissimilarity of the stimuli being compared. The model is compared to some published data on loudness matching and discrimination and to some new data of our own on the variability of loudness comparisons obtained in a two-interval, roving-level, loudness-discrimination experiment. PMID:915119

  9. NAA For Human Serum Analysis: Comparison With Conventional Analyses

    SciTech Connect

    Oliveira, Laura C.; Zamboni, Cibele B.; Medeiros, Jose A. G.; Azevedo, Maria R.

    2010-08-04

    Instrumental and Comparator methods of Neutron Activation Analysis (NAA) were applied to determine elements of clinical relevancy in serum samples of adult population (Sao Paulo city, Brazil). A comparison with the conventional analyses, Colorimetric for calcium, Titrymetric for chlorine and Ion Specific Electrode for sodium and potassium determination were also performed permitting a discussion about the performance of NAA methods for clinical chemistry research.

  10. An experimental manipulation of social comparison in social anxiety.

    PubMed

    Mitchell, Melissa A; Schmidt, Norman B

    2014-01-01

    Negative self-appraisal is thought to maintain social anxiety particularly when comparing oneself to others. Work on social comparison suggests that gender may moderate the effects of social comparison in social anxiety. Self-appraisals of the desirability of one's personality may be more important to women, whereas self-appraisal of signs of anxiety may be more important to men. Within each gender, those with high social anxiety are expected to report more negative self-appraisal when comparing themselves to someone else described as high achieving. This study is the first we are aware of that examined gender-based interactive effects after a social comparison manipulation. Participants read a bogus profile of a fellow student's adjustment to college. They were randomly assigned to read a profile suggesting that the fellow student was "high achieving" or more normative in his/her achievements. When comparing to a "high achieving" individual, men with high social anxiety reported the most negative self-appraisals of their signs of anxiety. In addition, greater social anxiety was associated with a poorer self-appraisal of personality only among men. The implications of the findings for conceptualizing the role of social comparison in social anxiety are discussed.

  11. A Comparison of Methods for Detecting Differential Distractor Functioning

    ERIC Educational Resources Information Center

    Koon, Sharon

    2010-01-01

    This study examined the effectiveness of the odds-ratio method (Penfield, 2008) and the multinomial logistic regression method (Kato, Moen, & Thurlow, 2009) for measuring differential distractor functioning (DDF) effects in comparison to the standardized distractor analysis approach (Schmitt & Bleistein, 1987). Students classified as participating…

  12. A comparison of filtering algorithms for GPS satellite navigation application

    NASA Technical Reports Server (NTRS)

    Tapley, B. D.; Peters, J. G.; Schutz, B. E.

    1979-01-01

    A comparison of three square root filter formulations with the standard extended Kalman filter is described. The characteristics of the algorithms were compared by simulating the application of a phase one GPS system to the determination of a LANDSAT-D Satellite.

  13. A Comparison of Deaf and Hearing Children's Reading Comprehension Profiles

    ERIC Educational Resources Information Center

    Kyle, Fiona E.; Cain, Kate

    2015-01-01

    Purpose: Although deaf children typically exhibit severe delays in reading achievement, there is a paucity of research looking at their text-level comprehension skills. We present a comparison of deaf and normally hearing readers' profiles on a commonly used reading comprehension assessment: the Neale Analysis of Reading Ability II. Methods:…

  14. A Comparison of Acculturation Measures among Hispanic/Latino Adolescents

    ERIC Educational Resources Information Center

    Unger, Jennifer B.; Ritt-Olson, Anamara; Wagner, Karla; Soto, Daniel; Baezconde-Garbanati, Lourdes

    2007-01-01

    Acculturation has been associated with numerous health and social outcomes among Hispanic/Latino adolescents. Various self-report scales have been used to measure acculturation, making comparisons of results across studies difficult. This study administered several commonly-used acculturation scales to 221 Hispanic/Latino 9th grade students in Los…

  15. NREL Pyrheliometer Comparisons: 22 September - 3 October 2008

    SciTech Connect

    Stoffel, T.; Reda, I.

    2009-02-01

    NREL Pyrheliometer Comparisons (NPCs) are held annually at the Solar Radiation Research Laboratory (SRRL) in Golden, Colorado. Open to all pyrheliometer owner/operators, the NPC provides an opportunity to determine the unique WRR transfer factor for each participating pyrheliometer. This paper reports on the results of NPC-2008, which was scheduled from September 22 to October 3, 2008.

  16. The Comparison of Visual Working Memory Representations with Perceptual Inputs

    ERIC Educational Resources Information Center

    Hyun, Joo-seok; Woodman, Geoffrey F.; Vogel, Edward K.; Hollingworth, Andrew; Luck, Steven J.

    2009-01-01

    The human visual system can notice differences between memories of previous visual inputs and perceptions of new visual inputs, but the comparison process that detects these differences has not been well characterized. In this study, the authors tested the hypothesis that differences between the memory of a stimulus array and the perception of a…

  17. Aligning the Structural Components across Learning Tasks of Case Comparisons

    ERIC Educational Resources Information Center

    Alfieri, Louis; Nokes, Timothy J.; Schunn, Christian D.

    2011-01-01

    Analogous thinking has been commonly discussed as being an inherent and distinguishing characteristic of human cognition (e.g., Gentner, 2010; Goldstone, Day, & Son, 2010; Holyoak, in press; Rittle-Johnson & Star, in press). Gentner (2003) has argued that as part of the human cognitive toolbox, comparison accompanied by the relational language to…

  18. Does Matching Quality Matter in Mode Comparison Studies?

    ERIC Educational Resources Information Center

    Zeng, Ji; Yin, Ping; Shedden, Kerby A.

    2015-01-01

    This article provides a brief overview and comparison of three matching approaches in forming comparable groups for a study comparing test administration modes (i.e., computer-based tests [CBT] and paper-and-pencil tests [PPT]): (a) a propensity score matching approach proposed in this article, (b) the propensity score matching approach used by…

  19. Direct Field and Reverberant Chamber Acoustic Test Comparisons

    NASA Technical Reports Server (NTRS)

    OConnell, Michael

    2007-01-01

    Reverberant and direct acoustic test comparisons were analyzed in this viewgraph presentation. The acoustic test data set includes: 1) CloudSat antenna subjected to PF reverberant chamber acoustic test; 2) CloudSat subjected to a PF direct speaker acoustic test; and 3) DAWN flight spacecraft subjected to PF direct speaker and a workmanship reverberant chamber acoustic test.

  20. Commercialising Comparison: Pearson Puts the TLC in Soft Capitalism

    ERIC Educational Resources Information Center

    Hogan, Anna; Sellar, Sam; Lingard, Bob

    2016-01-01

    This paper provides a critical policy analysis of "The Learning Curve" (TLC) (2012), an initiative developed by the multinational edu-business, Pearson, in conjunction with the Economist Intelligence Unit. "TLC" exemplifies the commercialising of comparison and the efforts of edu-businesses to strategically position themselves…