Probing the Dawn of Galaxies at z ~ 9-12 : New Constraints from HUDF12/XDF and CANDELS data
Oesch, P.A.; Bouwens, R.J.; Illingworth, G.D.; Labbé, I.; Franx, M.; Dokkum, van P.G.; Trenti, M.; Stiavelli, M.; Gonzalez, V.; Magee, D.
2013-01-01
We present a comprehensive analysis of z {gt} 8 galaxies based on ultra-deep WFC3/IR data. We exploit all the WFC3/IR imaging over the Hubble Ultra-Deep Field from the HUDF09 and the new HUDF12 program, in addition to the HUDF09 parallel field data, as well as wider area imaging over GOODS-South.
Probing the Dawn of Galaxies at z ~{} 9-12 : New Constraints from HUDF12/XDF and CANDELS data
Oesch, P.; Bouwens, R.J.; Illingworth, G.; Labbé, I.F.L.; Franx, M.; Dokkum, P.; Trenti, M.; Stiavelli, M.; Gonzalez, V.; Magee, D.
2013-01-01
We present a comprehensive analysis of z {gt} 8 galaxies based on ultra-deep WFC3/IR data. We exploit all the WFC3/IR imaging over the Hubble Ultra-Deep Field from the HUDF09 and the new HUDF12 program, in addition to the HUDF09 parallel field data, as well as wider area imaging over GOODS-South.
International Nuclear Information System (INIS)
Illingworth, G. D.; Magee, D.; Oesch, P. A.; Bouwens, R. J.; Labbé, I.; Franx, M.; Stiavelli, M.; Van Dokkum, P. G.; Trenti, M.; Carollo, C. M.; Gonzalez, V.
2013-01-01
The eXtreme Deep Field (XDF) combines data from 10 years of observations with the Hubble Space Telescope Advanced Camera for Surveys (ACS) and the Wide-Field Camera 3 Infra-Red (WFC3/IR) into the deepest image of the sky ever in the optical/near-IR. Since the initial observations of the Hubble Ultra-Deep Field (HUDF) in 2003, numerous surveys and programs, including supernovae follow-up, HUDF09, CANDELS, and HUDF12, have contributed additional imaging data across this region. However, these images have never been combined and made available as one complete ultra-deep image dataset. We combine them now with the XDF program. Our new and improved processing techniques provide higher quality reductions of the total dataset. All WFC3/IR and optical ACS data sets have been fully combined and accurately matched, resulting in the deepest imaging ever taken at these wavelengths, ranging from 29.1 to 30.3 AB mag (5σ in a 0.''35 diameter aperture) in 9 filters. The combined image therefore reaches to 31.2 AB mag 5σ (32.9 at 1σ) for a flat f ν source. The gains in the optical for the four filters done in the original ACS HUDF correspond to a typical improvement of 0.15 mag, with gains of 0.25 mag in the deepest areas. Such gains are equivalent to adding ∼130 to ∼240 orbits of ACS data to the HUDF. Improved processing alone results in a typical gain of ∼0.1 mag. Our 5σ (optical+near-IR) SExtractor catalogs reveal about 14,140 sources in the full field and about 7121 galaxies in the deepest part of the XDF
Bouwens, R. J.; Illingworth, G. D.; Blakeslee, J. P.; Franx, M.
2006-12-01
We have detected 506 i-dropouts (z~6 galaxies) in deep, wide-area HST ACS fields: HUDF, enhanced GOODS, and HUDF parallel ACS fields (HUDF-Ps). The contamination levels are ~92% are at z~6). With these samples, we present the most comprehensive, quantitative analyses of z~6 galaxies yet and provide optimal measures of the UV luminosity function (LF) and luminosity density at z~6, and their evolution to z~3. We redetermine the size and color evolution from z~6 to z~3. Field-to-field variations (cosmic variance), completeness, flux, and contamination corrections are modeled systematically and quantitatively. After corrections, we derive a rest-frame continuum UV (~1350 Å) LF at z~6 that extends to M1350,AB~-17.5 (0.04L*z=3). There is strong evidence for evolution of the LF between z~6 and z~3, most likely through a brightening (0.6+/-0.2 mag) of M* (at 99.7% confidence), although the degree depends on the faint-end slope. As expected from hierarchical models, the most luminous galaxies are deficient at z~6. Density evolution (φ*) is ruled out at >99.99% confidence. Despite large changes in the LF, the luminosity density at z~6 is similar to (0.82+/-0.21 times) that at z~3. Changes in the mean UV color of galaxies from z~6 to z~3 suggest an evolution in dust content, indicating that the true evolution is substantially larger: at z~6 the star formation rate density is just ~30% of the z~3 value. Our UV LF is consistent with z~6 galaxies providing the necessary UV flux to reionize the universe. Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program 9803. Observations have been carried out using the Very Large Telescope at the European Southern Observatory (ESO) Paranal Observatory, under program ID LP168.A-0485.
National Research Council Canada - National Science Library
Hathi, N. P; Jansen, R. A; Windhorst, R. A; Cohen, S. H; Keel, W. C; Corbin, M. R; Ryan, Jr, R. E
2007-01-01
The Hubble Ultra Deep Field (HUDF) contains a significant number of B-, V-, and iota'-band dropout objects, many of which were recently confirmed to be young star-forming galaxies at Z approximately equal 4-6...
Discovery of z ~ 8 Galaxies in the Hubble Ultra Deep Field from Ultra-Deep WFC3/IR Observations
Bouwens, R. J.; Illingworth, G. D.; Oesch, P. A.; Stiavelli, M.; van Dokkum, P.; Trenti, M.; Magee, D.; Labbé, I.; Franx, M.; Carollo, C. M.; Gonzalez, V.
2010-02-01
We utilize the newly acquired, ultra-deep WFC3/IR observations over the Hubble Ultra Deep Field (HUDF) to search for star-forming galaxies at z ~ 8-8.5, only 600 million years from recombination, using a Y 105-dropout selection. The new 4.7 arcmin2 WFC3/IR observations reach to ~28.8 AB mag (5σ) in the Y 105 J 125 H 160 bands. These remarkable data reach ~1.5 AB mag deeper than the previous data over the HUDF, and now are an excellent match to the HUDF optical ACS data. For our search criteria, we use a two-color Lyman break selection technique to identify z ~ 8-8.5Y 105-dropouts. We find five likely z ~ 8-8.5 candidates. The sources have H 160-band magnitudes of ~28.3 AB mag and very blue UV-continuum slopes, with a median estimated β of lsim-2.5 (where f λ vprop λβ). This suggests that z ~ 8 galaxies are not only essentially dust free but also may have very young ages or low metallicities. The observed number of Y 105-dropout candidates is smaller than the 20 ± 6 sources expected assuming no evolution from z ~ 6, but is consistent with the five expected extrapolating the Bouwens et al. luminosity function (LF) results to z ~ 8. These results provide evidence that the evolution in the LF seen from z ~ 7 to z ~ 3 continues to z ~ 8. The remarkable improvement in the sensitivity of WFC3/IR has enabled Hubble Space Telescope to cross a threshold, revealing star-forming galaxies at z~ 8-9. Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs 11563, 9797.
Energy Technology Data Exchange (ETDEWEB)
Bouwens, R. J.; Labbé, I.; Franx, M.; Smit, R. [Leiden Observatory, Leiden University, NL-2300 RA Leiden (Netherlands); Illingworth, G. D.; Oesch, P. A.; Gonzalez, V.; Magee, D. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Van Dokkum, P. G. [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); Trenti, M. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)
2014-10-01
We measure the UV-continuum slope β for over 4000 high-redshift galaxies over a wide range of redshifts z ∼ 4-8 and luminosities from the HST HUDF/XDF, HUDF09-1, HUDF09-2, ERS, CANDELS-N, and CANDELS-S data sets. Our new β results reach very faint levels at z ∼ 4 (–15.5 mag: 0.006 L{sub z=3}{sup ∗}), z ∼ 5 (–16.5 mag: 0.014 L{sub z=3}{sup ∗}), and z ∼ 6 and z ∼ 7 (–17 mag: 0.025 L{sub z=3}{sup ∗}). Inconsistencies between previous studies led us to conduct a comprehensive review of systematic errors and develop a new technique for measuring β that is robust against biases that arise from the impact of noise. We demonstrate, by object-by-object comparisons, that all previous studies, including our own and those done on the latest HUDF12 data set, suffered from small systematic errors in β. We find that after correcting for the systematic errors (typically Δβ ∼ 0.1-0.2) all β results at z ∼ 7 from different groups are in excellent agreement. The mean β we measure for faint (–18 mag: 0.1 L{sub z=3}{sup ∗}) z ∼ 4, z ∼ 5, z ∼ 6, and z ∼ 7 galaxies is –2.03 ± 0.03 ± 0.06 (random and systematic errors), –2.14 ± 0.06 ± 0.06, –2.24 ± 0.11 ± 0.08, and –2.30 ± 0.18 ± 0.13, respectively. Our new β values are redder than we have reported in the past, but bluer than other recent results. Our previously reported trend of bluer β's at lower luminosities is confirmed, as is the evolution to bluer β's at high redshifts. β appears to show only a mild luminosity dependence faintward of M {sub UV,AB} ∼ –19 mag, suggesting that the mean β asymptotes to ∼–2.2 to –2.4 for faint z ≥ 4 galaxies. At z ∼ 7, the observed β's suggest non-zero, but low dust extinction, and they agree well with values predicted in cosmological hydrodynamical simulations.
International Nuclear Information System (INIS)
Bouwens, R. J.; Labbé, I.; Franx, M.; Smit, R.; Illingworth, G. D.; Oesch, P. A.; Gonzalez, V.; Magee, D.; Van Dokkum, P. G.; Trenti, M.
2014-01-01
We measure the UV-continuum slope β for over 4000 high-redshift galaxies over a wide range of redshifts z ∼ 4-8 and luminosities from the HST HUDF/XDF, HUDF09-1, HUDF09-2, ERS, CANDELS-N, and CANDELS-S data sets. Our new β results reach very faint levels at z ∼ 4 (–15.5 mag: 0.006 L z=3 ∗ ), z ∼ 5 (–16.5 mag: 0.014 L z=3 ∗ ), and z ∼ 6 and z ∼ 7 (–17 mag: 0.025 L z=3 ∗ ). Inconsistencies between previous studies led us to conduct a comprehensive review of systematic errors and develop a new technique for measuring β that is robust against biases that arise from the impact of noise. We demonstrate, by object-by-object comparisons, that all previous studies, including our own and those done on the latest HUDF12 data set, suffered from small systematic errors in β. We find that after correcting for the systematic errors (typically Δβ ∼ 0.1-0.2) all β results at z ∼ 7 from different groups are in excellent agreement. The mean β we measure for faint (–18 mag: 0.1 L z=3 ∗ ) z ∼ 4, z ∼ 5, z ∼ 6, and z ∼ 7 galaxies is –2.03 ± 0.03 ± 0.06 (random and systematic errors), –2.14 ± 0.06 ± 0.06, –2.24 ± 0.11 ± 0.08, and –2.30 ± 0.18 ± 0.13, respectively. Our new β values are redder than we have reported in the past, but bluer than other recent results. Our previously reported trend of bluer β's at lower luminosities is confirmed, as is the evolution to bluer β's at high redshifts. β appears to show only a mild luminosity dependence faintward of M UV,AB ∼ –19 mag, suggesting that the mean β asymptotes to ∼–2.2 to –2.4 for faint z ≥ 4 galaxies. At z ∼ 7, the observed β's suggest non-zero, but low dust extinction, and they agree well with values predicted in cosmological hydrodynamical simulations.
DISCOVERY OF z ∼ 8 GALAXIES IN THE HUBBLE ULTRA DEEP FIELD FROM ULTRA-DEEP WFC3/IR OBSERVATIONS
International Nuclear Information System (INIS)
Bouwens, R. J.; Illingworth, G. D.; Magee, D.; Gonzalez, V.; Oesch, P. A.; Carollo, C. M.; Stiavelli, M.; Van Dokkum, P.; Trenti, M.; Labbe, I.; Franx, M.
2010-01-01
We utilize the newly acquired, ultra-deep WFC3/IR observations over the Hubble Ultra Deep Field (HUDF) to search for star-forming galaxies at z ∼ 8-8.5, only 600 million years from recombination, using a Y 105 -dropout selection. The new 4.7 arcmin 2 WFC3/IR observations reach to ∼28.8 AB mag (5σ) in the Y 105 J 125 H 160 bands. These remarkable data reach ∼1.5 AB mag deeper than the previous data over the HUDF, and now are an excellent match to the HUDF optical ACS data. For our search criteria, we use a two-color Lyman break selection technique to identify z ∼ 8-8.5Y 105 -dropouts. We find five likely z ∼ 8-8.5 candidates. The sources have H 160 -band magnitudes of ∼28.3 AB mag and very blue UV-continuum slopes, with a median estimated β of ∼ λ ∝ λ β ). This suggests that z ∼ 8 galaxies are not only essentially dust free but also may have very young ages or low metallicities. The observed number of Y 105 -dropout candidates is smaller than the 20 ± 6 sources expected assuming no evolution from z ∼ 6, but is consistent with the five expected extrapolating the Bouwens et al. luminosity function (LF) results to z ∼ 8. These results provide evidence that the evolution in the LF seen from z ∼ 7 to z ∼ 3 continues to z ∼ 8. The remarkable improvement in the sensitivity of WFC3/IR has enabled Hubble Space Telescope to cross a threshold, revealing star-forming galaxies at z∼ 8-9.
Unveiling the Galaxy Population at 1.3 < z < 4: the HUDF05 NICMOS Parallel Fields
Petty, Sara M.; deMello, Duilia F.; Wiklind, Tomy; Gardner, Jonathan P.; Mountain, Matt
2010-01-01
Using the Hubble Ultra Deep Field Near Infrared Camera and Multi-Object Spectrometer (HUDF-NICMOS) UDF05 parallel fields, we cross-matched 301 out of 630 galaxies with the ACS filters V606 and z850, NICMOS filters J110 and H160, and Spitzer IRAC filters at 3.6, 4.5, 5.8 , and 8.0 (mu)m. We modeled the spectral energy distributions (SEDs) to estimate: photometric redshifts, dust extinction, stellar mass, bolometric luminosity, starburst age and metallicity. To validate the photometric redshifts, comparisons with 16 spectroscopic redshifts give 75% within Delta or approx. 1.3. Based on the robustness of the photometric redshifts, we analyze a subsample of the 301 galaxies at 1.3 < or = z < or = 2 (35 objects) and 3 < or = z < or = 4 (31 objects) and determine that L(BoI) and the star formation rate increase significantly from z approx. 1.5 to 4. The Balmer decrement is indicative of more evolved galaxies, and at high redshifts, they serve as records of some of the first galaxies. Therefore, the galaxies in this sample are great candidates for future surveys with the James Webb Space Telescope and Atacama Large Millimeter Array.
Lyman Break Galaxies in the Hubble Ultra Deep Field through Deep U-Band Imaging
Rafelski, Marc; Wolfe, A. M.; Cooke, J.; Chen, H. W.; Armandroff, T. E.; Wirth, G. D.
2009-12-01
We introduce an extremely deep U-band image taken of the Hubble Ultra Deep Field (HUDF), with a one sigma depth of 30.7 mag arcsec-2 and a detection limiting magnitude of 28 mag arcsec-2. The observations were carried out on the Keck I telescope using the LRIS-B detector. The U-band image substantially improves the accuracy of photometric redshift measurements of faint galaxies in the HUDF at z=[2.5,3.5]. The U-band for these galaxies is attenuated by lyman limit absorption, allowing for more reliable selections of candidate Lyman Break Galaxies (LBGs) than from photometric redshifts without U-band. We present a reliable sample of 300 LBGs at z=[2.5,3.5] in the HUDF. Accurate redshifts of faint galaxies at z=[2.5,3.5] are needed to obtain empirical constraints on the star formation efficiency of neutral gas at high redshift. Wolfe & Chen (2006) showed that the star formation rate (SFR) density in damped Ly-alpha absorption systems (DLAs) at z=[2.5,3.5] is significantly lower than predicted by the Kennicutt-Schmidt law for nearby galaxies. One caveat to this result that we wish to test is whether LBGs are embedded in DLAs. If in-situ star formation is occurring in DLAs, we would see it as extended low surface brightness emission around LBGs. We shall use the more accurate photometric redshifts to create a sample of LBGs around which we will look for extended emission in the more sensitive and higher resolution HUDF images. The absence of extended emission would put limits on the SFR density of DLAs associated with LBGs at high redshift. On the other hand, detection of faint emission on scales large compared to the bright LBG cores would indicate the presence of in situ star formation in those DLAs. Such gas would presumably fuel the higher star formation rates present in the LBG cores.
The MUSE Hubble Ultra Deep Field Survey. IX. Evolution of galaxy merger fraction since z ≈ 6
Ventou, E.; Contini, T.; Bouché, N.; Epinat, B.; Brinchmann, J.; Bacon, R.; Inami, H.; Lam, D.; Drake, A.; Garel, T.; Michel-Dansac, L.; Pello, R.; Steinmetz, M.; Weilbacher, P. M.; Wisotzki, L.; Carollo, M.
2017-11-01
We provide, for the first time, robust observational constraints on the galaxy major merger fraction up to z ≈ 6 using spectroscopic close pair counts. Deep Multi Unit Spectroscopic Explorer (MUSE) observations in the Hubble Ultra Deep Field (HUDF) and Hubble Deep Field South (HDF-S) are used to identify 113 secure close pairs of galaxies among a parent sample of 1801 galaxies spread over a large redshift range (0.2 separation limit of 109.5 M⊙ or the median value of stellar mass computed in each redshift bin. Overall, the major close pair fraction for low-mass and massive galaxies follows the same trend. These new, homogeneous, and robust estimates of the major merger fraction since z ≈ 6 are in good agreement with recent predictions of cosmological numerical simulations. Based on observations made with ESO telescopes at the La Silla-Paranal Observatory under programmes 094.A-0289(B), 095.A-0010(A), 096.A-0045(A) and 096.A-0045(B).
Gardner, J. P.; Straughn, Amber N.; Meurer, Gerhardt R.; Pirzkal, Norbert; Cohen, Seth H.; Malhotra, Sangeeta; Rhoads, james; Windhorst, Rogier A.; Gardner, Jonathan P.; Hathi, Nimish P.;
2007-01-01
The Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) grism PEARS (Probing Evolution And Reionization Spectroscopically) survey provides a large dataset of low-resolution spectra from thousands of galaxies in the GOODS North and South fields. One important subset of objects in these data are emission-line galaxies (ELGs), and we have investigated several different methods aimed at systematically selecting these galaxies. Here we present a new methodology and results of a search for these ELGs in the PEARS observations of the Hubble Ultra Deep Field (HUDF) using a 2D detection method that utilizes the observation that many emission lines originate from clumpy knots within galaxies. This 2D line-finding method proves to be useful in detecting emission lines from compact knots within galaxies that might not otherwise be detected using more traditional 1D line-finding techniques. We find in total 96 emission lines in the HUDF, originating from 81 distinct "knots" within 63 individual galaxies. We find in general that [0 1111 emitters are the most common, comprising 44% of the sample, and on average have high equivalent widths (70% of [0 1111 emitters having rest-frame EW> 100A). There are 12 galaxies with multiple emitting knots; several show evidence of variations in H-alpha flux in the knots, suggesting that the differing star formation properties across a single galaxy can in general be probed at redshifts approximately greater than 0.2 - 0.4. The most prevalent morphologies are large face-on spirals and clumpy interacting systems, many being unique detections owing to the 2D method described here, thus highlighting the strength of this technique.
Lauer, Tod
1995-07-01
We request deep, near-IR (F814W) WFPC2 images of five nearby Brightest Cluster Galaxies (BCG) to calibrate the BCG Hubble diagram by the Surface Brightness Fluctuation (SBF) method. Lauer & Postman (1992) show that the BCG Hubble diagram measured out to 15,000 km s^-1 is highly linear. Calibration of the Hubble diagram zeropoint by SBF will thus yield an accurate far-field measure of H_0 based on the entire volume within 15,000 km s^-1, thus circumventing any strong biases caused by local peculiar velocity fields. This method of reaching the far field is contrasted with those using distance ratios between Virgo and Coma, or any other limited sample of clusters. HST is required as the ground-based SBF method is limited to team developed the SBF method, the first BCG Hubble diagram based on a full-sky, volume-limited BCG sample, played major roles in the calibration of WFPC and WFPC2, and are conducting observations of local galaxies that will validate the SBF zeropoint (through GTO programs). This work uses the SBF method to tie both the Cepheid and Local Group giant-branch distances generated by HST to the large scale Hubble flow, which is most accurately traced by BCGs.
THE UV CONTINUUM OF z > 1 STAR-FORMING GALAXIES IN THE HUBBLE ULTRAVIOLET ULTRADEEP FIELD
Energy Technology Data Exchange (ETDEWEB)
Kurczynski, Peter; Gawiser, Eric [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Rafelski, Marc [NASA Postdoctoral Program Fellow, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States); Teplitz, Harry I. [Infrared Processing and Analysis Center, MS 100-22, Caltech, Pasadena, CA 91125 (United States); Acquaviva, Viviana [New York City College of Technology, Brooklyn, NY 11201 (United States); Brown, Thomas M.; Coe, Dan; Grogin, Norman A.; Koekemoer, Anton M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); De Mello, Duilia F. [Laboratory for Observational Cosmology, Astrophysics Science Division, Code 665, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Finkelstein, Steven L. [Department of Astronomy, The University of Texas at Austin, Austin, TX 78712 (United States); Lee, Kyoung-soo [Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907 (United States); Scarlata, Claudia [Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Siana, Brian D. [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States)
2014-09-20
We estimate the UV continuum slope, β, for 923 galaxies in the range 1 < z < 8 in the Hubble Ultradeep Field (HUDF). These data include 460 galaxies at 1 < z < 2 down to an absolute magnitude M{sub UV}=−14(∼0.006 L{sub z=1}{sup ∗};0.02 L{sub z=0}{sup ∗}), comparable to dwarf galaxies in the local universe. We combine deep HST/UVIS photometry in F225W, F275W, F336W wavebands (UVUDF) with recent data from HST/WFC3/IR (HUDF12). Galaxies in the range 1 < z < 2 are significantly bluer than local dwarf galaxies. We find their mean (median) values <β > = – 1.382(– 1.830) ± 0.002 (random) ± 0.1 (systematic). We find comparable scatter in β (standard deviation = 0.43) to local dwarf galaxies and 30% larger scatter than z > 2 galaxies. We study the trends of β with redshift and absolute magnitude for binned sub-samples and find a modest color-magnitude relation, dβ/dM = –0.11 ± 0.01, and no evolution in dβ/dM with redshift. A modest increase in dust reddening with redshift and luminosity, ΔE(B – V) ∼ 0.1, and a comparable increase in the dispersion of dust reddening at z < 2, appears likely to explain the observed trends. At z > 2, we find trends that are consistent with previous works; combining our data with the literature in the range 1 < z < 8, we find a color evolution with redshift, dβ/dz = –0.09 ± 0.01 for low luminosity (0.05 L{sub z=3}{sup ∗}), and dβ/dz = –0.06 ± 0.01 for medium luminosity (0.25 L{sub z=3}{sup ∗}) galaxies.
Inami, H.; Bacon, R.; Brinchmann, J.; Richard, J.; Contini, T.; Conseil, S.; Hamer, S.; Akhlaghi, M.; Bouché, N.; Clément, B.; Desprez, G.; Drake, A. B.; Hashimoto, T.; Leclercq, F.; Maseda, M.; Michel-Dansac, L.; Paalvast, M.; Tresse, L.; Ventou, E.; Kollatschny, W.; Boogaard, L. A.; Finley, H.; Marino, R. A.; Schaye, J.; Wisotzki, L.
2017-11-01
We have conducted a two-layered spectroscopic survey (1' × 1' ultra deep and 3' × 3' deep regions) in the Hubble Ultra Deep Field (HUDF) with the Multi Unit Spectroscopic Explorer (MUSE). The combination of a large field of view, high sensitivity, and wide wavelength coverage provides an order of magnitude improvement in spectroscopically confirmed redshifts in the HUDF; i.e., 1206 secure spectroscopic redshifts for Hubble Space Telescope (HST) continuum selected objects, which corresponds to 15% of the total (7904). The redshift distribution extends well beyond z> 3 and to HST/F775W magnitudes as faint as ≈ 30 mag (AB, 1σ). In addition, 132 secure redshifts were obtained for sources with no HST counterparts that were discovered in the MUSE data cubes by a blind search for emission-line features. In total, we present 1338 high quality redshifts, which is a factor of eight increase compared with the previously known spectroscopic redshifts in the same field. We assessed redshifts mainly with the spectral features [O II] at zcolor selection (dropout) diagrams of high-z galaxies. The selection condition for F336W dropouts successfully captures ≈ 80% of the targeted z 2.7 galaxies. However, for higher redshift selections (F435W, F606W, and F775W dropouts), the success rates decrease to ≈ 20-40%. We empirically redefine the selection boundaries to make an attempt to improve them to ≈ 60%. The revised boundaries allow bluer colors that capture Lyα emitters with high Lyα equivalent widths falling in the broadbands used for the color-color selection. Along with this paper, we release the redshift and line flux catalog. Based on observations made with ESO telescopes at the La Silla Paranal Observatory under program IDs 094.A-0289(B), 095.A-0010(A), 096.A-0045(A) and 096.A-0045(B).MUSE Ultra Deep Field redshift catalogs (Full Table A.1) are available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http
Energy Technology Data Exchange (ETDEWEB)
Ono, Yoshiaki; Ouchi, Masami [Institute for Cosmic Ray Research, The University of Tokyo, Kashiwa 277-8582 (Japan); Curtis-Lake, Emma; McLure, Ross J.; Dunlop, James S.; Bowler, Rebecca A. A.; Rogers, Alexander B.; Cirasuolo, Michele [Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh EH9 3HJ (United Kingdom); Schenker, Matthew A.; Ellis, Richard S. [Department of Astrophysics, California Institute of Technology, MS 249-17, Pasadena, CA 91125 (United States); Robertson, Brant E.; Schneider, Evan; Stark, Daniel P. [Department of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Koekemoer, Anton M. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Charlot, Stephane [UPMC-CNRS, UMR7095, Institut d' Astrophysique, F-75014 Paris (France); Shimasaku, Kazuhiro [Department of Astronomy, Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan); Furlanetto, Steven R., E-mail: ono@icrr.u-tokyo.ac.jp [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)
2013-11-10
We analyze the redshift- and luminosity-dependent sizes of dropout galaxy candidates in the redshift range z ∼ 7-12 using deep images from the 2012 Hubble Ultra Deep Field (UDF12) campaign, which offers two advantages over that used in earlier work. First, we utilize the increased signal-to-noise ratio offered by the UDF12 imaging to provide improved measurements for known galaxies at z ≅ 6.5-8 in the HUDF. Second, because the UDF12 data have allowed the construction of the first robust galaxy sample in the HUDF at z > 8, we have been able to extend the measurement of average galaxy size out to higher redshifts. Restricting our measurements to sources detected at >15σ, we confirm earlier indications that the average half-light radii of z ∼ 7-12 galaxies are extremely small, 0.3-0.4 kpc, comparable to the sizes of giant molecular associations in local star-forming galaxies. We also confirm that there is a clear trend of decreasing half-light radius with increasing redshift, and provide the first evidence that this trend continues beyond z ≅ 8. Modeling the evolution of the average half-light radius as a power law, ∝(1 + z) {sup s}, we obtain a best-fit index of s=-1.30{sup +0.12}{sub -0.14} over z ∼ 4-12. A clear size-luminosity relation is evident in our dropout samples. This relation can be interpreted in terms of a constant surface density of star formation over a range in luminosity of 0.05-1.0 L{sub z=3}. The average star formation surface density in dropout galaxies is 2-3 orders of magnitude lower than that found in extreme starburst galaxies, but is comparable to that seen today in the centers of normal disk galaxies.
International Nuclear Information System (INIS)
Ono, Yoshiaki; Ouchi, Masami; Curtis-Lake, Emma; McLure, Ross J.; Dunlop, James S.; Bowler, Rebecca A. A.; Rogers, Alexander B.; Cirasuolo, Michele; Schenker, Matthew A.; Ellis, Richard S.; Robertson, Brant E.; Schneider, Evan; Stark, Daniel P.; Koekemoer, Anton M.; Charlot, Stephane; Shimasaku, Kazuhiro; Furlanetto, Steven R.
2013-01-01
We analyze the redshift- and luminosity-dependent sizes of dropout galaxy candidates in the redshift range z ∼ 7-12 using deep images from the 2012 Hubble Ultra Deep Field (UDF12) campaign, which offers two advantages over that used in earlier work. First, we utilize the increased signal-to-noise ratio offered by the UDF12 imaging to provide improved measurements for known galaxies at z ≅ 6.5-8 in the HUDF. Second, because the UDF12 data have allowed the construction of the first robust galaxy sample in the HUDF at z > 8, we have been able to extend the measurement of average galaxy size out to higher redshifts. Restricting our measurements to sources detected at >15σ, we confirm earlier indications that the average half-light radii of z ∼ 7-12 galaxies are extremely small, 0.3-0.4 kpc, comparable to the sizes of giant molecular associations in local star-forming galaxies. We also confirm that there is a clear trend of decreasing half-light radius with increasing redshift, and provide the first evidence that this trend continues beyond z ≅ 8. Modeling the evolution of the average half-light radius as a power law, ∝(1 + z) s , we obtain a best-fit index of s=-1.30 +0.12 -0.14 over z ∼ 4-12. A clear size-luminosity relation is evident in our dropout samples. This relation can be interpreted in terms of a constant surface density of star formation over a range in luminosity of 0.05-1.0 L z=3 . The average star formation surface density in dropout galaxies is 2-3 orders of magnitude lower than that found in extreme starburst galaxies, but is comparable to that seen today in the centers of normal disk galaxies
Delivering Hubble Discoveries to the Classroom
Eisenhamer, B.; Villard, R.; Weaver, D.; Cordes, K.; Knisely, L.
2013-04-01
Today's classrooms are significantly influenced by current news events, delivered instantly into the classroom via the Internet. Educators are challenged daily to transform these events into student learning opportunities. In the case of space science, current news events may be the only chance for educators and students to explore the marvels of the Universe. Inspired by these circumstances, the education and news teams developed the Star Witness News science content reading series. These online news stories (also available in downloadable PDF format) mirror the content of Hubble press releases and are designed for upper elementary and middle school level readers to enjoy. Educators can use Star Witness News stories to reinforce students' reading skills while exposing students to the latest Hubble discoveries.
2002-01-01
or simply dissipate? This image is a composite of data taken by Hubble's Wide Field Planetary Camera 2 in June 2001 by Bob O'Dell (Vanderbilt University) and collaborators and in January 2002 by The Hubble Heritage Team (STScI). Filters used to create this color image show oxygen, hydrogen, and nitrogen gas glowing in this object. Image Credit: NASA and the Hubble Heritage Team (STScI/AURA) Acknowledgment: C.R. O'Dell (Vanderbilt University)
Chandra Independently Determines Hubble Constant
2006-08-01
A critically important number that specifies the expansion rate of the Universe, the so-called Hubble constant, has been independently determined using NASA's Chandra X-ray Observatory. This new value matches recent measurements using other methods and extends their validity to greater distances, thus allowing astronomers to probe earlier epochs in the evolution of the Universe. "The reason this result is so significant is that we need the Hubble constant to tell us the size of the Universe, its age, and how much matter it contains," said Max Bonamente from the University of Alabama in Huntsville and NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala., lead author on the paper describing the results. "Astronomers absolutely need to trust this number because we use it for countless calculations." Illustration of Sunyaev-Zeldovich Effect Illustration of Sunyaev-Zeldovich Effect The Hubble constant is calculated by measuring the speed at which objects are moving away from us and dividing by their distance. Most of the previous attempts to determine the Hubble constant have involved using a multi-step, or distance ladder, approach in which the distance to nearby galaxies is used as the basis for determining greater distances. The most common approach has been to use a well-studied type of pulsating star known as a Cepheid variable, in conjunction with more distant supernovae to trace distances across the Universe. Scientists using this method and observations from the Hubble Space Telescope were able to measure the Hubble constant to within 10%. However, only independent checks would give them the confidence they desired, considering that much of our understanding of the Universe hangs in the balance. Chandra X-ray Image of MACS J1149.5+223 Chandra X-ray Image of MACS J1149.5+223 By combining X-ray data from Chandra with radio observations of galaxy clusters, the team determined the distances to 38 galaxy clusters ranging from 1.4 billion to 9.3 billion
Cosmological Hubble constant and nuclear Hubble constant
International Nuclear Information System (INIS)
Horbuniev, Amelia; Besliu, Calin; Jipa, Alexandru
2005-01-01
The evolution of the Universe after the Big Bang and the evolution of the dense and highly excited nuclear matter formed by relativistic nuclear collisions are investigated and compared. Values of the Hubble constants for cosmological and nuclear processes are obtained. For nucleus-nucleus collisions at high energies the nuclear Hubble constant is obtained in the frame of different models involving the hydrodynamic flow of the nuclear matter. Significant difference in the values of the two Hubble constant - cosmological and nuclear - is observed
HUBBLE VISION: A Planetarium Show About Hubble Space Telescope
Petersen, Carolyn Collins
1995-05-01
In 1991, a planetarium show called "Hubble: Report From Orbit" outlining the current achievements of the Hubble Space Telescope was produced by the independent planetarium production company Loch Ness Productions, for distribution to facilities around the world. The program was subsequently converted to video. In 1994, that program was updated and re-produced under the name "Hubble Vision" and offered to the planetarium community. It is periodically updated and remains a sought-after and valuable resource within the community. This paper describes the production of the program, and the role of the astronomical community in the show's production (and subsequent updates). The paper is accompanied by a video presentation of Hubble Vision.
z ~ 7-10 Galaxies in the HUDF and GOODS Fields: UV Luminosity Functions
Bouwens, Rychard J.; Illingworth, Garth D.; Franx, Marijn; Ford, Holland
2008-10-01
We use all available deep optical ACS and near-IR data over both the HUDF and the two GOODS fields to search for star-forming galaxies at zgtrsim 7 and constrain the UV LF within the first 700 Myr. Our data set includes ~23 arcmin2 of deep NICMOS J + H data and ~248 arcmin2 of ground-based (ISAAC+MOIRCS) data, coincident with ACS optical data of greater or equal depths. In total, we find eight ~ 7.3 z-dropouts in our search fields, but no z ~ 9 J-dropout candidates. A careful consideration of a wide variety of different contaminants suggest an overall contamination level of just ~12% for our z-dropout selection. After performing detailed simulations to accurately estimate the selection volumes, we derive constraints on the UV LFs at z ~ 7 and z ~ 9. For a faint-end slope α = - 1.74, our most likely values for MUV* and phiv* at z ~ 7 are -19.8 +/- 0.4 mag and 1.1+ 1.7-0.7 × 10-3 Mpc-3, respectively. Our search results for z ~ 9 J-dropouts set a 1 σ lower limit on MUV* of -19.6 mag assuming that phiv* and α are the same as their values at slightly later times. This lower limit on MUV* is 1.4 mag fainter than our best-fit value at z ~ 4, suggesting that the UV LF has undergone substantial evolution over this time period. No evolution is ruled out at 99% confidence from z ~ 7 to z ~ 6 and at 80% confidence from z ~ 9 to z ~ 7. We find that the mass-to-light ratio of halos evolves as ~(1 + z)-1 if we require that the observed brightening in MUV* with redshift [i.e., MUV* = (- 21.02 +/- 0.09) + (0.36 +/- 0.08) (z - 3.8) ] be consistent with the expected evolution in the halo mass function. Finally, we consider the shape of the UV LF at zgtrsim 5 and discuss the implications of the Schechter-like form of the observed LFs, particularly the unexpected abrupt cutoff at the bright end. Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5
A Unique test for Hubble's new Solar Arrays
2000-10-01
In mid-October, a team from the European Space Agency (ESA) and NASA will perform a difficult, never-before-done test on one of the Hubble Space Telescope's new solar array panels. Two of these panels, or arrays, will be installed by astronauts in November 2001, when the Space Shuttle Columbia visits Hubble on a routine service mission. The test will ensure that the new arrays are solid and vibration free before they are installed on orbit. The test will be conducted at ESA's European Space Research and Technology Center (ESTEC) in Noordwijk, The Netherlands. Because of the array's size, the facility's special features, and ESA's longstanding experience with Hubble's solar arrays, ESTEC is the only place in the world the test can be performed. This test is the latest chapter in a longstanding partnership between ESA and NASA on the Hubble Space Telescope. The Large Space Simulator at ESTEC, ESA's world-class test facility, features a huge vacuum chamber containing a bank of extremely bright lights that simulate the Sun's intensity - including sunrise and sunset. By exposing the solar wing to the light and temperature extremes of Hubble's orbit, engineers can verify how the new set of arrays will act in space. Hubble orbits the Earth once every 90 minutes. During each orbit, the telescope experiences 45 minutes of searing sunlight and 45 minutes of frigid darkness. This test will detect any tiny vibrations, or jitters, caused by these dramatic, repeated changes. Even a small amount of jitter can affect Hubble's sensitive instruments and interfere with observations. Hubble's first set of solar arrays experienced mild jitter and was replaced in 1993 with a much more stable pair. Since that time, advances in solar cell technology have led to the development of even more efficient arrays. In 2001, NASA will take advantage of these improvements, by fitting Hubble with a third-generation set of arrays. Though smaller, this new set generates more power than the previous
Hubble Observes Surface of Titan
1994-01-01
Scientists for the first time have made images of the surface of Saturn's giant, haze-shrouded moon, Titan. They mapped light and dark features over the surface of the satellite during nearly a complete 16-day rotation. One prominent bright area they discovered is a surface feature 2,500 miles across, about the size of the continent of Australia.Titan, larger than Mercury and slightly smaller than Mars, is the only body in the solar system, other than Earth, that may have oceans and rainfall on its surface, albeit oceans and rain of ethane-methane rather than water. Scientists suspect that Titan's present environment -- although colder than minus 289 degrees Fahrenheit, so cold that water ice would be as hard as granite -- might be similar to that on Earth billions of years ago, before life began pumping oxygen into the atmosphere.Peter H. Smith of the University of Arizona Lunar and Planetary Laboratory and his team took the images with the Hubble Space Telescope during 14 observing runs between Oct. 4 - 18. Smith announced the team's first results last week at the 26th annual meeting of the American Astronomical Society Division for Planetary Sciences in Bethesda, Md. Co-investigators on the team are Mark Lemmon, a doctoral candidate with the UA Lunar and Planetary Laboratory; John Caldwell of York University, Canada; Larry Sromovsky of the University of Wisconsin; and Michael Allison of the Goddard Institute for Space Studies, New York City.Titan's atmosphere, about four times as dense as Earth's atmosphere, is primarily nitrogen laced with such poisonous substances as methane and ethane. This thick, orange, hydrocarbon haze was impenetrable to cameras aboard the Pioneer and Voyager spacecraft that flew by the Saturn system in the late 1970s and early 1980s. The haze is formed as methane in the atmosphere is destroyed by sunlight. The hydrocarbons produced by this methane destruction form a smog similar to that found over large cities, but is much thicker
Lehtonen, Ken
1999-01-01
This is a report to the Third Annual International Virtual Company Conference, on The Development of a Virtual Company to Support the Reengineering of the NASA/Goddard Hubble Space Telescope (HST) Control Center System. It begins with a HST Science "Commercial": Brief Tour of Our Universe showing various pictures taken from the Hubble Space Telescope. The presentation then reviews the project background and goals. Evolution of the Control Center System ("CCS Inc.") is then reviewed. Topics of Interest to "virtual companies" are reviewed: (1) "How To Choose A Team" (2) "Organizational Model" (3) "The Human Component" (4) "'Virtual Trust' Among Teaming Companies" (5) "Unique Challenges to Working Horizontally" (6) "The Cultural Impact" (7) "Lessons Learned".
European astronomers' successes with the Hubble Space Telescope*
1997-02-01
[Figure: Laguna Nebula] Their work spans all aspects of astronomy, from the planets to the most distant galaxies and quasars, and the following examples are just a few European highlights from Hubble's second phase, 1994-96. A scarcity of midget stars Stars less massive and fainter than the Sun are much numerous in the Milky Way Galaxy than the big bright stars that catch the eye. Guido De Marchi and Francesco Paresce of the European Southern Observatory as Garching, Germany, have counted them. With the wide-field WFPC2 camera, they have taken sample censuses within six globular clusters, which are large gatherings of stars orbiting independently in the Galaxy. In every case they find that the commonest stars have an output of light that is only one-hundredth of the Sun's. They are ten times more numerous than stars like the Sun. More significant for theories of the Universe is a scarcity of very faint stars. Some astronomers have suggested that vast numbers of such stars could account for the mysterious dark matter, which makes stars and galaxies move about more rapidly than expected from the mass of visible matter. But that would require an ever-growing count of objects at low brightnesses, and De Marchi and Paresce find the opposite to be the case -- the numbers diminish. There may be a minimum size below which Nature finds starmaking difficult. The few examples of very small stars seen so far by astronomers may be, not the heralds of a multitude of dark-matter stars, but rareties. Unchanging habits in starmaking Confirmation that very small stars are scarce comes from Gerry Gilmore of the Institute of Astronomy in Cambridge (UK). He leads a European team that analyses long-exposure images in the WFPC2 camera, obtained as a by-product when another instrument is examining a selected object. The result is an almost random sample of well-observed stars and galaxies. The most remarkable general conclusion is that the make-up of stellar populations never seems to
Lindberg Christensen, Lars; Kornmesser, M
2006-01-01
Hubble: 15 Years of Discovery was a key element of the European Space Agency's 15th anniversary celebration activities for the 1990 launch of the NASA/ESA Hubble Space Telescope. As an observatory in space, Hubble is one of the most successful scientific projects of all time, both in terms of scientific output and its immediate public appeal.
International Nuclear Information System (INIS)
Labbe, I.; Gonzalez, V.; Bouwens, R. J.; Illingworth, G. D.; Magee, D.; Franx, M.; Trenti, M.; Oesch, P. A.; Carollo, C. M.; Van Dokkum, P. G.; Stiavelli, M.; Kriek, M.
2010-01-01
We investigate the Spitzer/IRAC properties of 36 z ∼ 7 z 850 -dropout galaxies and three z ∼ 8 Y 098 galaxies derived from deep/wide-area WFC3/IR data of the Early Release Science, the ultradeep HUDF09, and wide-area NICMOS data. We fit stellar population synthesis models to the spectral energy distributions to derive mean redshifts, stellar masses, and ages. The z ∼ 7 galaxies are best characterized by substantial ages (>100 Myr) and M/L V ∼ 0.2. The main trend with decreasing luminosity is that of bluing of the far-UV slope from β ∼ -2.0 to β ∼ -3.0. This can be explained by decreasing metallicity, except for the lowest luminosity galaxies (0.1L* z =3 ), where low metallicity and smooth star formation histories (SFHs) fail to match the blue far-UV and moderately red H - [3.6] color. Such colors may require episodic SFHs with short periods of activity and quiescence ('on-off' cycles) and/or a contribution from emission lines. The stellar mass of our sample of z ∼ 7 star-forming galaxies correlates with star formation rate (SFR) according to log M* = 8.70(±0.09) + 1.06(±0.10)log SFR, implying that star formation may have commenced at z > 10. No galaxies are found with SFRs much higher or lower than the past averaged SFR suggesting that the typical star formation timescales are probably a substantial fraction of the Hubble time. We report the first IRAC detection of Y 098 -dropout galaxies at z ∼ 8. The average rest-frame U - V ∼ 0.3 (AB) of the three galaxies are similar to faint z ∼ 7 galaxies, implying similar M/L. The stellar mass density to M UV,AB +0.7 -1.0 x 10 6 M sun Mpc -3 , following log ρ*(z) = 10.6(±0.6) - 4.4(±0.7) log(1 + z) [M sun Mpc -3 ] over 3 < z < 8.
The new European Hubble archive
De Marchi, Guido; Arevalo, Maria; Merin, Bruno
2016-01-01
The European Hubble Archive (hereafter eHST), hosted at ESA's European Space Astronomy Centre, has been released for public use in October 2015. The eHST is now fully integrated with the other ESA science archives to ensure long-term preservation of the Hubble data, consisting of more than 1 million observations from 10 different scientific instruments. The public HST data, the Hubble Legacy Archive, and the high-level science data products are now all available to scientists through a single, carefully designed and user friendly web interface. In this talk, I will show how the the eHST can help boost archival research, including how to search on sources in the field of view thanks to precise footprints projected onto the sky, how to obtain enhanced previews of imaging data and interactive spectral plots, and how to directly link observations with already published papers. To maximise the scientific exploitation of Hubble's data, the eHST offers connectivity to virtual observatory tools, easily integrates with the recently released Hubble Source Catalog, and is fully accessible through ESA's archives multi-mission interface.
NASA and ESA astronauts visit ESO. Hubble repair team meets European astronomers in Garching.
1994-02-01
On Wednesday, February 16, 1994, seven NASA and ESA astronauts and their spouses will spend a day at the Headquarters of the European Southern Observatory. They are the members of the STS-61 crew that successfully repaired the Hubble Space Telescope during a Space Shuttle mission in December 1993. This will be the only stop in Germany during their current tour of various European countries. ESO houses the Space Telescope European Coordinating Facility (ST/ECF), a joint venture by the European Space Agency and ESO. This group of astronomers and computer specialists provide all services needed by European astronomers for observations with the Space Telescope. Currently, the European share is about 20 of the total time available at this telescope. During this visit, a Press Conference will be held on Wednesday, February 16, 11:45 - 12:30 at the ESO Headquarters Karl-Schwarzschild-Strasse 2 D-85748 Garching bei Munchen. Please note that participation in this Press Conference is by invitation only. Media representatives may obtain invitations from Mrs. E. Volk, ESO Information Service at this address (Tel.: +49-89-32006276; Fax.: +49-89-3202362), until Friday, February 11, 1994. After the Press Conference, between 12:30 - 14:00, a light refreshment will be served at the ESO Headquarters to all participants. >From 14:00 - 15:30, the astronauts will meet with students and teachers from the many scientific institutes in Garching in the course of an open presentation at the large lecture hall of the Physics Department of the Technical University. It is a 10 minute walk from ESO to the hall. Later the same day, the astronauts will be back at ESO for a private discussion of various space astronomy issues with their astronomer colleagues, many of whom are users of the Hubble Space Telescope, as well as ground-based telescopes at the ESO La Silla Observatory and elsewhere. The astronauts continue to Switzerland in the evening.
Dark Energy and the Hubble Law
Chernin, A. D.; Dolgachev, V. P.; Domozhilova, L. M.
The Big Bang predicted by Friedmann could not be empirically discovered in the 1920th, since global cosmological distances (more than 300-1000 Mpc) were not available for observations at that time. Lemaitre and Hubble studied receding motions of galaxies at local distances of less than 20-30 Mpc and found that the motions followed the (nearly) linear velocity-distance relation, known now as Hubble's law. For decades, the real nature of this phenomenon has remained a mystery, in Sandage's words. After the discovery of dark energy, it was suggested that the dynamics of local expansion flows is dominated by omnipresent dark energy, and it is the dark energy antigravity that is able to introduce the linear velocity-distance relation to the flows. It implies that Hubble's law observed at local distances was in fact the first observational manifestation of dark energy. If this is the case, the commonly accepted criteria of scientific discovery lead to the conclusion: In 1927, Lemaitre discovered dark energy and Hubble confirmed this in 1929.
Labbé, I.; González, V.; Bouwens, R. J.; Illingworth, G. D.; Franx, M.; Trenti, M.; Oesch, P. A.; van Dokkum, P. G.; Stiavelli, M.; Carollo, C. M.; Kriek, M.; Magee, D.
2010-06-01
We investigate the Spitzer/IRAC properties of 36 z ~ 7 z 850-dropout galaxies and three z ~ 8 Y 098 galaxies derived from deep/wide-area WFC3/IR data of the Early Release Science, the ultradeep HUDF09, and wide-area NICMOS data. We fit stellar population synthesis models to the spectral energy distributions to derive mean redshifts, stellar masses, and ages. The z ~ 7 galaxies are best characterized by substantial ages (>100 Myr) and M/LV ≈ 0.2. The main trend with decreasing luminosity is that of bluing of the far-UV slope from β ~ -2.0 to β ~ -3.0. This can be explained by decreasing metallicity, except for the lowest luminosity galaxies (0.1L* z = 3), where low metallicity and smooth star formation histories (SFHs) fail to match the blue far-UV and moderately red H - [3.6] color. Such colors may require episodic SFHs with short periods of activity and quiescence ("on-off" cycles) and/or a contribution from emission lines. The stellar mass of our sample of z ~ 7 star-forming galaxies correlates with star formation rate (SFR) according to log M* = 8.70(±0.09) + 1.06(±0.10)log SFR, implying that star formation may have commenced at z > 10. No galaxies are found with SFRs much higher or lower than the past averaged SFR suggesting that the typical star formation timescales are probably a substantial fraction of the Hubble time. We report the first IRAC detection of Y 098-dropout galaxies at z ~ 8. The average rest-frame U - V ≈ 0.3 (AB) of the three galaxies are similar to faint z ~ 7 galaxies, implying similar M/L. The stellar mass density to M UV,AB Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs 11563, 9797. Based on observations with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA through contract 125790 issued by JPL/Caltech. Based on service
HUBBLE provides multiple views of how to feed a black hole
1998-05-01
fuel from a devoured galaxy, it may be oblivious to the rest of the galaxy and the collision," said Ethan Schreier of the Space Telescope Science Institute, Baltimore, MD. Schreier and an international team of co-investigators used Hubble's Near Infrared Camera and Multi-Object Spectrometer to probe deeper into the galaxy's mysterious heart than anyone has before. The hot gas disk viewed by Hubble investigators is perpendicular to the galaxy's outer dust belt, while the black hole's own internal accretion disk of superhot gas falling into it is tilted approximately diagonally to these axes. "We have found a complicated situation of a disk within a disk within a disk, all pointing in different directions," Schreier said. It is not clear if the black hole was always present in the host galaxy or belonged to the spiral galaxy that fell into the core, or if it is the product of the merger of a pair of smaller black holes that lived in the two once-separate galaxies. Having an active galaxy just 10 million light-years away from Earth rather than hundreds of millions or billions of light-years distant offers astronomers a unique laboratory for understanding the elusive details of the behavior of supermassive black holes as fueled by galaxy collisions. "Though Hubble has seen hot gas disks around black holes in other galaxies, the infrared camera has for the first time allowed us to peer at this relatively nearby, very active, but obscured black hole region," Schreier added. The team of astronomers is awaiting further Hubble data to continue its study of the disk, as well as ground-based spectroscopic observations to measure the velocity of entrapped material around the black hole. This will allow the astronomers to better calculate the black hole's mass. The current results are scheduled to appear in the June 1, 1998 issue of Astrophysical Journal Letters. Images and further information related to these results are available on the Internet at the following URLs: http
Hubble expansion in a Euclidean framework
International Nuclear Information System (INIS)
Alfven, H.
1979-01-01
There now seems to be strong evidence for a non-cosmological interpretation of the QSO redshift - in any case, so strong that it is of interest to investigate the consequences. The purpose of this paper is to construct a model of the Hubble expansion which is as far as possible from the conventional Big Bang model without coming in conflict with any well-established observational results (while introducing no new laws of physics). This leads to an essentially Euclidean metagalactic model (see Table I) with very little mass outside one-third or half of the Hubble radius. The total kinetic energy of the Hubble expansion need only to be about 5% of the rest mass energy. Present observations support backwards in time extrapolation of the Hubble expansion to a 'minimum size galaxy' Rsub(m), which may have any value in 0 26 cm. Other arguments speak in favor of a size close to the upper value, say Rsub(m) = 10 26 cm (Table II). As this size is probably about 100 times the Schwarzschild limit, an essentially Euclidean description is allowed. The kinetic energy of the Hubble expansion may derive from an intense QSO-like activity in the minimum size metagalaxy, with an energy release corresponding to the annihilation of a few solar masses per galaxy per year. Some of the conclusions based on the Big Bang hypothesis are criticized and in several cases alternative interpretations are suggested. A comparison between the Euclidean and the conventional models is given in Table III. (orig.)
Bouwens, R. J.; Illingworth, G. D.; Franx, Marijn; Ford, Holland
2007-12-01
We use the ACS BViz data from the HUDF and all other deep HST ACS fields (including the GOODS fields) to find large samples of star-forming galaxies at z~4 and ~5 and to extend our previous z~6 sample. These samples contain 4671, 1416, and 627 B-, V-, and i-dropouts, respectively, and reach to extremely low luminosities [(0.01-0.04)L*z=3 or MUV~-16 to -17], allowing us to determine the rest-frame UV LF and faint-end slope α at z~4-6 to high accuracy. We find faint-end slopes α=-1.73+/-0.05, -1.66+/-0.09, and -1.74+/-0.16 at z~4, ~5, and ~6, respectively, suggesting that the faint-end slope is very steep and shows little evolution with cosmic time. We find that M*UV brightens considerably in the 0.7 Gyr from z~6 to ~4 (by ~0.7 mag from M*UV=-20.24+/-0.19 to -20.98+/-0.10). The observed increase in the characteristic luminosity over this range is almost identical to that expected for the halo mass function, suggesting that the observed evolution is likely due to the hierarchical coalescence and merging of galaxies. The evolution in φ* is not significant. The UV luminosity density at z~6 is modestly lower than (0.45+/-0.09 times) that at z~4 (integrated to -17.5 mag) although a larger change is seen in the dust-corrected SFR density. We thoroughly examine published LF results and assess the reasons for their wide dispersion. We argue that the results reported here are the most robust available. The extremely steep faint-end slopes α found here suggest that lower luminosity galaxies play a significant role in reionizing the universe. Finally, recent search results for galaxies at z~7-8 are used to extend our estimates of the evolution of M* from z~7-8 to z~4. Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs 9425, 9575, 9803, 9978, 10189, 10339, 10340, and 10632.
HST's 10th anniversary, ESA and Hubble : changing our vision
2000-04-01
With the astronauts who took part in the most recent Servicing Mission (SM3A) in attendance, ESA is taking the opportunity to give a - first - complete overview of Europe's major contribution to the HST mission. It will also review the first ten years of operations and the outstanding results that have "changed our vision" of the cosmos. A new fully European outreach initiative - the "European Space Agency Hubble Information Centre" - will be presented and officially launched; it has been set up by ESA to provide information on Hubble from a European perspective. A public conference will take place in the afternoon to celebrate Hubble's achievements midway through its life. Ten years of outstanding performance Launched on 24 April 1990, Hubble is now midway through its operating life and it is considered one of the most successful space science missions ever. So far more than 10,000 scientific papers based on Hubble results have been published and European scientists have contributed to more than 25% of these. Not only has Hubble produced a rich harvest of scientific results, it has impressed the man in the street with its beautiful images of the sky. Thousands of headlines all over the world have given direct proof of the public's great interest in the mission - 'The deepest images ever', 'The sharpest view of the Universe', 'Measurements of the earliest galaxies' and many others, all reflecting Hubble's performance as a top-class observatory. The Servicing Missions that keep the observatory and its instruments in prime condition are one of the innovative ideas behind Hubble. Astronauts have serviced Hubble three times, and ESA astronauts have taken part in two of these missions. Claude Nicollier (CH) worked with American colleagues on the First Servicing Mission, when Hubble's initial optical problems were repaired. On the latest, Servicing Mission 3A, both Claude Nicollier and Jean-François Clervoy (F) were members of the crew. Over the next 10 years European
Directory of Open Access Journals (Sweden)
Neal Jackson
2015-09-01
Full Text Available I review the current state of determinations of the Hubble constant, which gives the length scale of the Universe by relating the expansion velocity of objects to their distance. There are two broad categories of measurements. The first uses individual astrophysical objects which have some property that allows their intrinsic luminosity or size to be determined, or allows the determination of their distance by geometric means. The second category comprises the use of all-sky cosmic microwave background, or correlations between large samples of galaxies, to determine information about the geometry of the Universe and hence the Hubble constant, typically in a combination with other cosmological parameters. Many, but not all, object-based measurements give H_0 values of around 72–74 km s^–1 Mpc^–1, with typical errors of 2–3 km s^–1 Mpc^–1. This is in mild discrepancy with CMB-based measurements, in particular those from the Planck satellite, which give values of 67–68 km s^–1 Mpc^–1 and typical errors of 1–2 km s^–1 Mpc^–1. The size of the remaining systematics indicate that accuracy rather than precision is the remaining problem in a good determination of the Hubble constant. Whether a discrepancy exists, and whether new physics is needed to resolve it, depends on details of the systematics of the object-based methods, and also on the assumptions about other cosmological parameters and which datasets are combined in the case of the all-sky methods.
Focusing Cosmic Telescopes: Exploring Redshift z ~ 5-6 Galaxies with the Bullet Cluster 1E0657 - 56
Bradač, Maruša; Treu, Tommaso; Applegate, Douglas; Gonzalez, Anthony H.; Clowe, Douglas; Forman, William; Jones, Christine; Marshall, Phil; Schneider, Peter; Zaritsky, Dennis
2009-12-01
The gravitational potential of clusters of galaxies acts as a cosmic telescope allowing us to find and study galaxies at fainter limits than otherwise possible and thus probe closer to the epoch of formation of the first galaxies. We use the Bullet cluster 1E0657 - 56 (z = 0.296) as a case study, because its high mass and merging configuration makes it one of the most efficient cosmic telescopes we know. We develop a new algorithm to reconstruct the gravitational potential of the Bullet cluster based on a non-uniform adaptive grid, combining strong and weak gravitational lensing data derived from deep Hubble Space Telescope/Advanced Camera for Surveys F606W-F775W-F850LP and ground-based imaging. We exploit this improved mass map to study z ~ 5-6 Lyman break galaxies (LBGs), which we detect as dropouts. One of the LBGs is multiply imaged, providing a geometric confirmation of its high redshift, and is used to further improve our mass model. We quantify the uncertainties in the magnification map reconstruction in the intrinsic source luminosity, and in the volume surveyed, and show that they are negligible compared to sample variance when determining the luminosity function of high-redshift galaxies. With shallower and comparable magnitude limits to Hubble Ultra Deep Field (HUDF) and Great Observatories Origins Deep Survey (GOODS), the Bullet cluster observations, after correcting for magnification, probe deeper into the luminosity function of the high-redshift galaxies than GOODS and only slightly shallower than HUDF. We conclude that accurately focused cosmic telescopes are the most efficient way to sample the bright end of the luminosity function of high-redshift galaxies and—in case they are multiply imaged—confirm their redshifts. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5
HUBBLE PINPOINTS WHITE DWARFS IN GLOBULAR CLUSTER
2002-01-01
Peering deep inside a cluster of several hundred thousand stars, NASA's Hubble Space Telescope uncovered the oldest burned-out stars in our Milky Way Galaxy. Located in the globular cluster M4, these small, dying stars - called white dwarfs - are giving astronomers a fresh reading on one of the biggest questions in astronomy: How old is the universe? The ancient white dwarfs in M4 are about 12 to 13 billion years old. After accounting for the time it took the cluster to form after the big bang, astronomers found that the age of the white dwarfs agrees with previous estimates for the universe's age. In the top panel, a ground-based observatory snapped a panoramic view of the entire cluster, which contains several hundred thousand stars within a volume of 10 to 30 light-years across. The Kitt Peak National Observatory's 0.9-meter telescope took this picture in March 1995. The box at left indicates the region observed by the Hubble telescope. The Hubble telescope studied a small region of the cluster. A section of that region is seen in the picture at bottom left. A sampling of an even smaller region is shown at bottom right. This region is only about one light-year across. In this smaller region, Hubble pinpointed a number of faint white dwarfs. The blue circles pinpoint the dwarfs. It took nearly eight days of exposure time over a 67-day period to find these extremely faint stars. Globular clusters are among the oldest clusters of stars in the universe. The faintest and coolest white dwarfs within globular clusters can yield a globular cluster's age. Earlier Hubble observations showed that the first stars formed less than 1 billion years after the universe's birth in the big bang. So, finding the oldest stars puts astronomers within arm's reach of the universe's age. M4 is 7,000 light-years away in the constellation Scorpius. Hubble's Wide Field and Planetary Camera 2 made the observations from January through April 2001. These optical observations were combined to
Hubble and the Language of Images
Levay, Z. G.
2005-12-01
Images released from the Hubble Space Telescope have been very highly regarded by the astronomy-attentive public for at least a decade. Due in large part to these images, Hubble has become an iconic figure, even among the general public. This iconic status is both a boon and a burden for those who produce the stream of images fl owing from this telescope. While the benefits of attention are fairly obvious, the negative aspects are less visible. One of the most persistent challenges is the need to continue to deliver images that "top" those released before. In part this can be accomplished because of Hubble's upgraded instrumentation. But it can also be a source of pressure that could, if left unchecked, erode ethical boundaries in our communication with the public. These pressures are magnified in an atmosphere of uncertainty with regard to the future of the mission.
Hubble Legacy Archive And The Public
Harris, Jessica; Whitmore, B.; Eisenhamer, B.; Bishop, M.; Knisely, L.
2012-01-01
The Hubble Legacy Archive (HLA) at the Space Telescope Science Institute (STScI) hosts the Image of the Month (IOTM) Series. The HLA is a joint project of STScI, the Space Telescope European Coordinating Facility (ST-ECF), and the Canadian Astronomy Data Centre (CADC). The HLA is designed optimize science from the Hubble Space Telescope by providing online enhanced Hubble products and advanced browsing capabilities. The IOTM's are created for astronomers and the public to highlight various features within HLA, such as the "Interactive Display", "Footprint” and "Inventory” features to name a few. We have been working with the Office of Public Outreach (OPO) to create a standards based educational module for middle school to high school students of the IOTM: Rings and the Moons of Uranus. The set of Uranus activities are highlighted by a movie that displays the orbit of five of Uranus’ largest satellites. We made the movie based on eight visits of Uranus from 2000-06-16 to 2000-06-18, using the PC chip on the Wide Field Planetary Camera 2 (WFPC2) and filter F850LP (proposal ID: 8680). Students will be engaged in activities that will allow them to "discover” the rings and satellites around Uranus, calculate the orbit of the satellites, and introduces students to analyze real data from Hubble.
Hubble again views Saturn's Rings Edge-on
1995-01-01
Saturn's magnificent ring system is seen tilted edge-on -- for the second time this year -- in this NASA Hubble Space Telescope picture taken on August 10, 1995, when the planet was 895 million miles (1,440 million kilometers) away. Hubble snapped the image as Earth sped back across Saturn's ring plane to the sunlit side of the rings. Last May 22, Earth dipped below the ring plane, giving observers a brief look at the backlit side of the rings. Ring-plane crossing events occur approximately every 15 years. Earthbound observers won't have as good a view until the year 2038. Several of Saturn's icy moons are visible as tiny starlike objects in or near the ring plane. They are from left to right, Enceladus, Tethys, Dione and Mimas. 'The Hubble data shows numerous faint satellites close to the bright rings, but it will take a couple of months to precisely identify them,' according to Steve Larson (University of Arizona). During the May ring plane crossing, Hubble detected two, and possibly four, new moons orbiting Saturn. These new observations also provide a better view of the faint E ring, 'to help determine the size of particles and whether they will pose a collision hazard to the Cassini spacecraft,' said Larson. The picture was taken with Hubble's Wide Field Planetary Camera 2 in wide field mode. This image is a composite view, where a long exposure of the faint rings has been combined with a shorter exposure of Saturn's disk to bring out more detail. When viewed edge-on, the rings are so dim they almost disappear because they are very thin -- probably less than a mile thick.The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/
Energy Technology Data Exchange (ETDEWEB)
Ishigaki, Masafumi; Ouchi, Masami; Ono, Yoshiaki [Institute for Cosmic Ray Research, The University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Kawamata, Ryota; Shimasaku, Kazuhiro [Department of Astronomy, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Oguri, Masamune, E-mail: ishigaki@icrr.u-tokyo.ac.jp [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
2015-01-20
We present comprehensive analyses of faint dropout galaxies up to z ∼ 10 with the first full-depth data set of the A2744 lensing cluster and parallel fields observed by the Hubble Frontier Fields (HFF) program. We identify 54 dropouts at z ∼ 5-10 in the HFF fields and enlarge the size of the z ∼ 9 galaxy sample obtained to date. Although the number of highly magnified (μ ∼ 10) galaxies is small because of the tiny survey volume of strong lensing, our study reaches the galaxies' intrinsic luminosities comparable to the deepest-field HUDF studies. We derive UV luminosity functions with these faint dropouts, carefully evaluating by intensive simulations the combination of observational incompleteness and lensing effects in the image plane, including magnification, distortion, and multiplication of images, with the evaluation of mass model dependencies. Our results confirm that the faint-end slope, α, is as steep as –2 at z ∼ 6-8 and strengthen the evidence for the rapid decrease of UV luminosity densities, ρ{sub UV}, at z > 8 from the large z ∼ 9 sample. We examine whether the rapid ρ{sub UV} decrease trend can be reconciled with the large Thomson scattering optical depth, τ{sub e}, measured by cosmic microwave background experiments, allowing a large space of free parameters, such as an average ionizing photon escape fraction and a stellar-population-dependent conversion factor. No parameter set can reproduce both the rapid ρ{sub UV} decrease and the large τ {sub e}. It is possible that the ρ{sub UV} decrease moderates at z ≳ 11, that the free parameters significantly evolve toward high z, or that there exist additional sources of reionization such as X-ray binaries and faint active galactic nuclei.
International Nuclear Information System (INIS)
Ishigaki, Masafumi; Ouchi, Masami; Ono, Yoshiaki; Kawamata, Ryota; Shimasaku, Kazuhiro; Oguri, Masamune
2015-01-01
We present comprehensive analyses of faint dropout galaxies up to z ∼ 10 with the first full-depth data set of the A2744 lensing cluster and parallel fields observed by the Hubble Frontier Fields (HFF) program. We identify 54 dropouts at z ∼ 5-10 in the HFF fields and enlarge the size of the z ∼ 9 galaxy sample obtained to date. Although the number of highly magnified (μ ∼ 10) galaxies is small because of the tiny survey volume of strong lensing, our study reaches the galaxies' intrinsic luminosities comparable to the deepest-field HUDF studies. We derive UV luminosity functions with these faint dropouts, carefully evaluating by intensive simulations the combination of observational incompleteness and lensing effects in the image plane, including magnification, distortion, and multiplication of images, with the evaluation of mass model dependencies. Our results confirm that the faint-end slope, α, is as steep as –2 at z ∼ 6-8 and strengthen the evidence for the rapid decrease of UV luminosity densities, ρ UV , at z > 8 from the large z ∼ 9 sample. We examine whether the rapid ρ UV decrease trend can be reconciled with the large Thomson scattering optical depth, τ e , measured by cosmic microwave background experiments, allowing a large space of free parameters, such as an average ionizing photon escape fraction and a stellar-population-dependent conversion factor. No parameter set can reproduce both the rapid ρ UV decrease and the large τ e . It is possible that the ρ UV decrease moderates at z ≳ 11, that the free parameters significantly evolve toward high z, or that there exist additional sources of reionization such as X-ray binaries and faint active galactic nuclei
Version 1 of the Hubble Source Catalog
Whitmore, Bradley C.; Allam, Sahar S.; Budavári, Tamás; Casertano, Stefano; Downes, Ronald A.; Donaldson, Thomas; Fall, S. Michael; Lubow, Stephen H.; Quick, Lee; Strolger, Louis-Gregory; Wallace, Geoff; White, Richard L.
2016-06-01
The Hubble Source Catalog is designed to help optimize science from the Hubble Space Telescope (HST) by combining the tens of thousands of visit-based source lists in the Hubble Legacy Archive (HLA) into a single master catalog. Version 1 of the Hubble Source Catalog includes WFPC2, ACS/WFC, WFC3/UVIS, and WFC3/IR photometric data generated using SExtractor software to produce the individual source lists. The catalog includes roughly 80 million detections of 30 million objects involving 112 different detector/filter combinations, and about 160,000 HST exposures. Source lists from Data Release 8 of the HLA are matched using an algorithm developed by Budavári & Lubow. The mean photometric accuracy for the catalog as a whole is better than 0.10 mag, with relative accuracy as good as 0.02 mag in certain circumstances (e.g., bright isolated stars). The relative astrometric residuals are typically within 10 mas, with a value for the mode (I.e., most common value) of 2.3 mas. The absolute astrometric accuracy is better than 0''\\hspace{-0.5em}. 1 for most sources, but can be much larger for a fraction of fields that could not be matched to the PanSTARRS, SDSS, or 2MASS reference systems. In this paper we describe the database design with emphasis on those aspects that enable the users to fully exploit the catalog while avoiding common misunderstandings and potential pitfalls. We provide usage examples to illustrate some of the science capabilities and data quality characteristics, and briefly discuss plans for future improvements to the Hubble Source Catalog.
European astronaut selected for the third Hubble Space Telescope
1998-08-01
The STS-104 crew will rendezvous with the orbiting Hubble Space Telescope, which is the size of a city bus, capture it using the Shuttle's Canadian robot arm and secure it in Columbia's payload bay. Then, working in teams of two, the four astronauts will leave the Shuttle's pressurised cabin and venture into the payload bay, performing a variety of tasks that will improve the productivity and reliability of the telescope. The four astronauts will perform a series of six "extravehicular" activities in the open space environment. Such activities are commonly called spacewalks, but this term does little justice to the considerable physical and mental efforts that astronauts need to make in doing the very demanding work involved. The Shuttle commander and pilot for this flight have not yet been appointed, but the four designated mission specialists begin training for the STS-104 mission immediately. "The ambitious nature of this mission, with its six spacewalks, made it important for the payload crew to begin training as early as possible," said David C. Leestma, NASA Director of Flight Crew Operations at the Johnson Space Center in Houston, to which Claude Nicollier is on resident assignment from ESA's European Astronaut Centre in Cologne, Germany, the home base of the European astronaut corps. The Hubble Space Telescope was launched into orbit in April 1990. It is one of the most capable optical telescopes available to astronomers today, producing images and spectral observations at the forefront of astronomy. The European Space Agency contributed a 15 share to the development of Hubble. One of the five scientific instruments on board, the Faint Object Camera, was built by a European industrial consortium made up of British Aerospace, Dornier and Matra under a contract with the European Space Agency. The solar arrays which provide Hubble with electrical power were manufactured by British Aerospace and Dornier. In its eight years of operation, the telescope has not
Hubble induced mass after inflation in spectator field models
Energy Technology Data Exchange (ETDEWEB)
Fujita, Tomohiro [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, CA 94306 (United States); Harigaya, Keisuke, E-mail: tomofuji@stanford.edu, E-mail: keisukeh@icrr.u-tokyo.ac.jp [Department of Physics, University of California, Berkeley, CA 94720 (United States)
2016-12-01
Spectator field models such as the curvaton scenario and the modulated reheating are attractive scenarios for the generation of the cosmic curvature perturbation, as the constraints on inflation models are relaxed. In this paper, we discuss the effect of Hubble induced masses on the dynamics of spectator fields after inflation. We pay particular attention to the Hubble induced mass by the kinetic energy of an oscillating inflaton, which is generically unsuppressed but often overlooked. In the curvaton scenario, the Hubble induced mass relaxes the constraint on the property of the inflaton and the curvaton, such as the reheating temperature and the inflation scale. We comment on the implication of our discussion for baryogenesis in the curvaton scenario. In the modulated reheating, the predictions of models e.g. the non-gaussianity can be considerably altered. Furthermore, we propose a new model of the modulated reheating utilizing the Hubble induced mass which realizes a wide range of the local non-gaussianity parameter.
Testing the isotropy of the Hubble expansion
Migkas, K.; Plionis, M.
2016-01-01
Abstract: We have used the Union2.1 SNIa compilation to search for possible Hubble expansion anisotropies, dividing the sky in 9 solid angles containing roughly the same number of SNIa, as well as in two Galactic hemispheres. We identified only one sky region, containing 82 SNIa (~15% of total sample with z > 0.02), that indeed appears to share a Hubble expansion significantly different from the rest of the sample. However, this behaviour can be attributed to the joint "erratic" behaviour of ...
Oesch, P. A.; Bouwens, R. J.; Illingworth, G. D.; Labbé, I.; Stefanon, M.
2018-03-01
We present an analysis of all prime HST legacy fields spanning >800 arcmin2 in the search for z ∼ 10 galaxy candidates and the study of their UV luminosity function (LF). In particular, we present new z ∼ 10 candidates selected from the full Hubble Frontier Field (HFF) data set. Despite the addition of these new fields, we find a low abundance of z ∼ 10 candidates with only nine reliable sources identified in all prime HST data sets that include the HUDF09/12, the HUDF/XDF, all of the CANDELS fields, and now the HFF survey. Based on this comprehensive search, we find that the UV luminosity function decreases by one order of magnitude from z ∼ 8 to z ∼ 10 over a four-magnitude range. This also implies a decrease of the cosmic star formation rate density by an order of magnitude within 170 Myr from z ∼ 8 to z ∼ 10. We show that this accelerated evolution compared to lower redshift can entirely be explained by the fast build up of the dark matter halo mass function at z > 8. Consequently, the predicted UV LFs from several models of galaxy formation are in good agreement with this observed trend, even though the measured UV LF lies at the low end of model predictions. The difference is generally still consistent within the Poisson and cosmic variance uncertainties. We discuss the implications of these results in light of the upcoming James Webb Space Telescope mission, which is poised to find much larger samples of z ∼ 10 galaxies as well as their progenitors at less than 400 Myr after the big bang. Based on data obtained with the Hubble Space Telescope operated by AURA, Inc. for NASA under contract NAS5-26555.
Hubble 2020: Outer Planet Atmospheres Legacy (OPAL) Program
Simon, Amy
2017-08-01
Long time base observations of the outer planets are critical in understanding the atmospheric dynamics and evolution of the gas giants. We propose yearly monitoring of each giant planet for the remainder of Hubble's lifetime to provide a lasting legacy of increasingly valuable data for time-domain studies. The Hubble Space Telescope is a unique asset to planetary science, allowing high spatial resolution data with absolute photometric knowledge. For the outer planets, gas/ice giant planets Jupiter, Saturn, Uranus and Neptune, many phenomena happen on timescales of years to decades, and the data we propose are beyond the scope of a typical GO program. Hubble is the only platform that can provide high spatial resolution global studies of cloud coloration, activity, and motion on a consistent time basis to help constrain the underlying mechanics.
Carnegie Hubble Program: A Mid-Infrared Calibration of the Hubble Constant
Freedman, Wendy L.; Madore, Barry F.; Scowcroft, Victoria; Burns, Chris; Monson, Andy; Persson, S. Eric; Seibert, Mark; Rigby, Jane
2012-01-01
Using a mid-infrared calibration of the Cepheid distance scale based on recent observations at 3.6 micrometers with the Spitzer Space Telescope, we have obtained a new, high-accuracy calibration of the Hubble constant. We have established the mid-IR zero point of the Leavitt law (the Cepheid period-luminosity relation) using time-averaged 3.6 micrometers data for 10 high-metallicity, MilkyWay Cepheids having independently measured trigonometric parallaxes. We have adopted the slope of the PL relation using time-averaged 3.6micrometers data for 80 long-period Large Magellanic Cloud (LMC) Cepheids falling in the period range 0.8 < log(P) < 1.8.We find a new reddening-corrected distance to the LMC of 18.477 +/- 0.033 (systematic) mag. We re-examine the systematic uncertainties in H(sub 0), also taking into account new data over the past decade. In combination with the new Spitzer calibration, the systematic uncertainty in H(sub 0) over that obtained by the Hubble Space Telescope Key Project has decreased by over a factor of three. Applying the Spitzer calibration to the Key Project sample, we find a value of H(sub 0) = 74.3 with a systematic uncertainty of +/-2.1 (systematic) kilometers per second Mpc(sup -1), corresponding to a 2.8% systematic uncertainty in the Hubble constant. This result, in combination with WMAP7measurements of the cosmic microwave background anisotropies and assuming a flat universe, yields a value of the equation of state for dark energy, w(sub 0) = -1.09 +/- 0.10. Alternatively, relaxing the constraints on flatness and the numbers of relativistic species, and combining our results with those of WMAP7, Type Ia supernovae and baryon acoustic oscillations yield w(sub 0) = -1.08 +/- 0.10 and a value of N(sub eff) = 4.13 +/- 0.67, mildly consistent with the existence of a fourth neutrino species.
HUBBLE SPIES MOST DISTANT SUPERNOVA EVER SEEN
2002-01-01
Using NASA's Hubble Space Telescope, astronomers pinpointed a blaze of light from the farthest supernova ever seen, a dying star that exploded 10 billion years ago. The detection and analysis of this supernova, called 1997ff, is greatly bolstering the case for the existence of a mysterious form of dark energy pervading the cosmos, making galaxies hurl ever faster away from each other. The supernova also offers the first glimpse of the universe slowing down soon after the Big Bang, before it began speeding up. This panel of images, taken with the Wide Field and Planetary Camera 2, shows the supernova's cosmic neighborhood; its home galaxy; and the dying star itself. Astronomers found this supernova in 1997 during a second look at the northern Hubble Deep Field [top panel], a tiny region of sky first explored by the Hubble telescope in 1995. The image shows the myriad of galaxies Hubble spied when it peered across more than 10 billion years of time and space. The white box marks the area where the supernova dwells. The photo at bottom left is a close-up view of that region. The white arrow points to the exploding star's home galaxy, a faint elliptical. Its redness is due to the billions of old stars residing there. The picture at bottom right shows the supernova itself, distinguished by the white dot in the center. Although this stellar explosion is among the brightest beacons in the universe, it could not be seen directly in the Hubble images. The stellar blast is so distant from Earth that its light is buried in the glow of its host galaxy. To find the supernova, astronomers compared two pictures of the 'deep field' taken two years apart. One image was of the original Hubble Deep Field; the other, the follow-up deep-field picture taken in 1997. Using special computer software, astronomers then measured the light from the galaxies in both images. Noting any changes in light output between the two pictures, the computer identified a blob of light in the 1997 picture
Way, Michael J.
2013-01-01
Edwin Hubble is famous for a number of discoveries that are well known to amateur and professional astronomers, students and the general public. The origins of these discoveries are examined and it is demonstrated that, in each case, a great deal of supporting evidence was already in place. In some cases the discoveries had either already been made, or competing versions were not adopted for complex scientific and sociological reasons.
New Hubble Servicing Mission to upgrade instruments
2006-10-01
The history of the NASA/ESA Hubble Space Telescope is dominated by the familiar sharp images and amazing discoveries that have had an unprecedented scientific impact on our view of the world and our understanding of the universe. Nevertheless, such important contributions to science and humankind have only been possible as result of regular upgrades and enhancements to Hubble’s instrumentation. Using the Space Shuttle for this fifth Servicing Mission underlines the important role that astronauts have played and continue to play in increasing the Space Telescope’s lifespan and scientific power. Since the loss of Columbia in 2003, the Shuttle has been successfully launched on three missions, confirming that improvements made to it have established the required high level of safety for the spacecraft and its crew. “There is never going to be an end to the science that we can do with a machine like Hubble”, says David Southwood, ESA’s Director of Science. “Hubble is our way of exploring our origins. Everyone should be proud that there is a European element to it and that we all are part of its success at some level.” This Servicing Mission will not just ensure that Hubble can function for perhaps as much as another ten years; it will also increase its capabilities significantly in key areas. This highly visible mission is expected to take place in 2008 and will feature several space walks. As part of the upgrade, two new scientific instruments will be installed: the Cosmic Origins Spectrograph and Wide Field Camera 3. Each has advanced technology sensors that will dramatically improve Hubble’s potential for discovery and enable it to observe faint light from the youngest stars and galaxies in the universe. With such an astounding increase in its science capabilities, this orbital observatory will continue to penetrate the most distant regions of outer space and reveal breathtaking phenomena. “Today, Hubble is producing more science than ever before in
Finding our Origins with the Hubble and James Webb Space Telescopes
Gardner, Jonathan P.
2009-01-01
NASA is planning a successor to the Hubble Space Telescope designed to study the origins of galaxies, stars, planets and life in the universe. In this talk, Dr. Gardner will discuss the origin and evolution of galaxies, beginning with the Big Bang and tracing what we have learned with Hubble through to the present day. He will show that results from studies with Hubble have led to plans for its successor, the James Webb Space Telescope. Webb is scheduled to launch in 2014, and is designed to find the first galaxies that formed in the distant past and to penetrate the dusty clouds of gas where stars are still forming today. He will compare Webb to Hubble, and discuss recent progress in the construction of the observatory.
An Overdensity of i-Dropouts among a Population of Excess Field Objects in the Virgo Cluster
Yan, Haojing; Hathi, Nimish P.; Windhorst, Rogier A.
2008-03-01
Using a set of deep imaging data obtained by the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST) shortly after its deployment, Yan, Windhorst, & Cohen found a large number of F775W-band dropouts (i-dropouts), which are consistent with being galaxies at z ≈ 6. The surface density of i-dropouts thus derived, however, is an order of magnitude higher than those subsequent studies found in other deep ACS fields, including the Hubble Ultra Deep Field (HUDF). Here we revisit this problem, using both existing and new data. We confirm that the large overdensity of i-dropouts does exist in this field, and that their optical-to-IR colors are similar to those in the HUDF. However, we have discovered that the i-dropout overdensity is accompanied by an even larger excess of faint field objects in this region and its vicinity. This large excess of field objects is most likely caused by the fact that we have resolved the faint diffuse light extending from an interacting galaxy pair in the Virgo Cluster, M60/NGC 4647, which lies several arcminutes away from the region where the excess is found. The i-dropouts in this field are within the magnitude range where this excess of field objects occurs, and their spatial distribution seems to follow the same gradient as the entire excess field population. This excess population is also red in color, and the red wing of its color distribution continuously extends to the regime where the i-dropouts reside. While we still cannot completely rule out the possibility that the overdensity of i-dropouts might be a genuine large-scale structure of galaxies at z ≈ 6, we prefer the interpretation that most of them are part of the excess stellar population related to M60/NGC 4647. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These
1995-08-01
International Astronomer Team Witnesses Very Ancient Stellar Explosion A few months ago, a violent stellar explosion -- a supernova -- was discovered in an extremely distant galaxy by an international team of astronomers [1]. This is the very promising first result of a recently initiated, dedicated search for such objects. Subsequent spectral observations have shown this to be the most distant supernova ever observed. Although it is very faint, it has been possible to classify it as a supernova of Type Ia, a kind that is particularly well suited for cosmological distance determinations. A Very Efficient Supernova Search Programme The present discovery was made during the team's first observations with the 4-metre telescope at the Cerro Tololo Inter-American Observatory in Chile. This telescope is equipped with a wide-field camera at its prime focus that enables the simultaneous recording of the images of even very faint objects in a 15-arcminute field. Hundreds of distant galaxies are located in a field of this size and this observational method is therefore very well suited for a search of faint and transient supernovae in such galaxies. With a carefully planned observing sequence, it is possible to image up to 55 sky fields per night. A comparison with earlier exposures makes it possible to detect suddenly appearing supernovae as faint points of light near the galaxy in which the exploding star is located (the parent galaxy). A crucial feature of the new programme is the possibility to perform follow-up spectroscopic observations, whenever a new supernova is discovered. For this, the team has obtained access to several other large telescopes, including the ESO 3.5-metre New Technology Telescope (NTT), the 3.9-metre Anglo-Australian Telescope (AAT) and the Multi-Mirror Telescope (MMT) in Arizona, U.S.A.. The Spectrum of the Supernova The present supernova was first detected at Tololo on March 30, 1995. It was given the official designation SN 1995K, and its
Replacement vs. Renovation: The Reincarnation of Hubble Middle School
Ogurek, Douglas J.
2010-01-01
At the original Hubble Middle School, neither the views (a congested Roosevelt Road and glimpses of downtown Wheaton) nor the century-old facility that offered them was very inspiring. Built at the start of the 20th century, the 250,000-square-foot building was converted from Wheaton Central High School to Hubble Middle School in the early 1980s.…
Directory of Open Access Journals (Sweden)
Susanna Bisogni
2018-01-01
Full Text Available The cosmological model is at present not tested between the redshift of the farthest observed supernovae (z ~ 1.4 and that of the Cosmic Microwave Background (z ~ 1,100. Here we introduce a new method to measure the cosmological parameters: we show that quasars can be used as “standard candles” by employing the non-linear relation between their intrinsic UV and X-ray emission as an absolute distance indicator. We built a sample of ~1,900 quasars with available UV and X-ray observations, and produced a Hubble Diagram up to z ~ 5. The analysis of the quasar Hubble Diagram, when used in combination with supernovae, provides robust constraints on the matter and energy content in the cosmos. The application of this method to forthcoming, larger quasar samples, will also provide tight constraints on the dark energy equation of state and its possible evolution with time.
Astronomers celebrate a year of new Hubble results
1995-02-01
"We are beginning to understand that because of these observations we are going to have to change the way we look at the Universe," said ESA's Dr Duccio Macchetto, Associate Director for Science Programs at the Space Telescope Science Institute (STScI), Baltimore, Maryland, USA. The European Space Agency plays a major role in the Hubble Space Telescope programme. The Agency provided one of the telescope's four major instruments, called the Faint Object Camera, and two sets of electricity-generating solar arrays. In addition, 15 ESA scientific and technical staff work at the STScI. In return for this contribution, European astronomers are entitled to 15 percent of the telescope's observing time, although currently they account for 20 percent of all observations. "This is a testimony to the quality of the European science community", said Dr Roger Bonnet, Director of Science at ESA. "We are only guaranteed 15 percent of the telescope's use, but consistently receive much more than that." Astronomers from universities, observatories and research institutes across Europe lead more than 60 investigations planned for the telescope's fifth observing cycle, which begins this summer. Many more Europeans contribute to teams led by other astronomers. Looking back to the very start of time European astronomer Dr Peter Jakobsen used ESA's Faint Object Camera to confirm that helium was present in the early Universe. Astronomers had long predicted that 90 percent of the newly born Universe consisted of hydrogen, with helium making up the remainder. Before the refurbished Hubble came along, it was easy to detect the hydrogen, but the primordial helium remained elusive. The ultraviolet capabilities of the telescope, combined with the improvement in spatial resolution following the repair, made it possible for Dr Jakobsen to obtain an image of a quasar close to the edge of the known Universe. A spectral analysis of this picture revealed the quasar's light, which took 13 billion years
Cataclysmic variables, Hubble-Sandage variables and eta Carinae
International Nuclear Information System (INIS)
Bath, G.T.
1980-01-01
The Hubble-Sandage variables are the most luminous stars in external galaxies. They were first investigated by Hubble and Sandage (1953) for use as distance indicators. Their main characteristics are high luminosity, blue colour indices, and irregular variability. Spectroscopically they show hydrogen and helium in emission with occasionally weaker FeII and [FeII], and no Balmer jump (Humphreys 1975, 1978). In this respect they closely resemble cataclysmic variables, particularly dwarf novae. In the quiescent state dwarf novae show broad H and HeI, together with a strong UV continuum. In contrast to the spectroscopic similarities, the luminosities could hardly differ more. Rather than being the brightest stars known, quiescent dwarf novae are as faint or fainter than the sun. It is suggested that the close correspondence between the spectral appearance of the two classes combined with the difference in luminosity is well accounted for by a model of Hubble-Sandage variables in which the same physical processes are occurring, but on a larger scale. (Auth.)
Cosmic Collisions The Hubble Atlas of Merging Galaxies
Christensen, Lars Lindberg; Martin, Davide
2009-01-01
Lars Lindberg Christensen, Raquel Yumi Shida & Davide De Martin Cosmic Collisions: The Hubble Atlas of Merging Galaxies Like majestic ships in the grandest night, galaxies can slip ever closer until their mutual gravitational interaction begins to mold them into intricate figures that are finally, and irreversibly, woven together. It is an immense cosmic dance, choreographed by gravity. Cosmic Collisions contains a hundred new, many thus far unpublished, images of colliding galaxies from the NASA/ESA Hubble Space Telescope. It is believed that many present-day galaxies, including the Milky Way, were assembled from such a coalescence of smaller galaxies, occurring over billions of years. Triggered by the colossal and violent interaction between the galaxies, stars form from large clouds of gas in firework bursts, creating brilliant blue star clusters. The importance of these cosmic encounters reaches far beyond the stunning Hubble images. They may, in fact, be among the most important processes that shape ...
Hubble expansion in static spacetime
International Nuclear Information System (INIS)
Rossler, Otto E.; Froehlich, Dieter; Movassagh, Ramis; Moore, Anthony
2007-01-01
A recently proposed mechanism for light-path expansion in a static spacetime is based on the moving-lenses paradigm. Since the latter is valid independently of whether space expands or not, a static universe can be used to better see the implications. The moving-lenses paradigm is related to the paradigm of dynamical friction. If this is correct, a Hubble-like law is implicit. It is described quantitatively. A bent in the Hubble-like line is predictably implied. The main underlying assumption is Price's Principle (PI 3 ). If the theory is sound, the greatest remaining problem in cosmology becomes the origin of hydrogen. Since Blandford's jet production mechanism for quasars is too weak, a generalized Hawking radiation hidden in the walls of cosmic voids is invoked. A second prediction is empirical: slow pattern changes in the cosmic microwave background. A third is ultra-high redshifts for Giacconi quasars. Bruno's eternal universe in the spirit of Augustine becomes a bit less outlandish
Freedman, Wendy L.; Madore, Barry F.; Scowcroft, Vicky; Mnso, Andy; Persson, S. E.; Rigby, Jane; Sturch, Laura; Stetson, Peter
2011-01-01
We present an overview of and preliminary results from an ongoing comprehensive program that has a goal of determining the Hubble constant to a systematic accuracy of 2%. As part of this program, we are currently obtaining 3.6 micron data using the Infrared Array Camera (IRAC) on Spitzer, and the program is designed to include JWST in the future. We demonstrate that the mid-infrared period-luminosity relation for Cepheids at 3.6 microns is the most accurate means of measuring Cepheid distances to date. At 3.6 microns, it is possible to minimize the known remaining systematic uncertainties in the Cepheid extragalactic distance scale. We discuss the advantages of 3.6 micron observations in minimizing systematic effects in the Cepheid calibration of the Hubble constant including the absolute zero point, extinction corrections, and the effects of metallicity on the colors and magnitudes of Cepheids. We are undertaking three independent tests of the sensitivity of the mid-IR Cepheid Leavitt Law to metallicity, which when combined will allow a robust constraint on the effect. Finally, we are providing a new mid-IR Tully-Fisher relation for spiral galaxies.
Hubble Space Telescope: a Vision to 2020 and Beyond: The Hubble Source Catalog
Strolger, Louis-Gregory
2016-01-01
The Hubble Source Catalog (HSC) is an initiative centered on what science would be enabled by a master catalog of all the sources HST has imaged over its lifetime. The first version of this catalog was released in early 2015, and included approximately 30 million sources from archived direct imaging with WFPC2, ACS (through 2011), and WFC3 (to 2014). Version 2, scheduled for release in early 2016, will feed off the Hubble Legacy Archive DR9 release, updating the ACS sources with more detections, and more direct imaging, through to mid-2015. This talk will overview the properties and goals of the HSC in terms of its source detection, object resolution, confusion limits, and overall astrometric and photometric precision. I will also discuss the connections to other MAST activities (e.g., the Discovery Portal interface), to STScI and user products (e.g., the Spectroscopic Catalog and High-Level Science Products), and to community resources (e.g., Pan-STARRS, SDSS, and eventually GAIA). The HSC successfully amalgamates the diverse observations with HST, and despite the limitations in uniformity on the sky, will be an important reference for JWST, LSST, and other future telescopes.
Energy Technology Data Exchange (ETDEWEB)
Liu, F. S. [College of Physical Science and Technology, Shenyang Normal University, Shenyang 110034 (China); Guo Yicheng; Koo, David C.; Trump, Jonathan R.; Barro, Guillermo; Yesuf, Hassen; Faber, S. M.; Cheung, Edmond [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Giavalisco, M. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Cassata, P. [Aix Marseille Universite, CNRS, LAM-Laboratoire d' Astrophysique de Marseille, F-13388 Marseille (France); Koekemoer, A. M.; Grogin, Norman A. [Space Telescope Science Institute, 3700 San Martin Boulevard, Baltimore, MD 21218 (United States); Pentericci, L.; Castellano, M. [INAF Osservatorio Astronomico di Roma, Via Frascati 33, I-00040 Monteporzio (RM) (Italy); Mao, Shude [National Astronomical Observatories, Chinese Academy of Sciences, A20 Datun Road, Beijing 100012 (China); Xia, X. Y. [Tianjin Astrophysics Center, Tianjin Normal University, Tianjin 300387 (China); Hathi, Nimish P. [Observatories of the Carnegie Institution for Science, Pasadena, CA 91101 (United States); Huang, Kuang-Han [Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Kocevski, Dale [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506-0055 (United States); McGrath, Elizabeth J., E-mail: fengshan@ucolick.org [Department of Physics and Astronomy, Colby College, Mayflower Hill Drive, Waterville, ME 0490 (United States); and others
2013-06-01
We have made a serendipitous discovery of a massive ({approx}5 Multiplication-Sign 10{sup 11} M{sub Sun }) cD galaxy at z = 1.096 in a candidate-rich cluster in the Hubble Ultra Deep Field (HUDF) area of GOODS-South. This brightest cluster galaxy (BCG) is the most distant cD galaxy confirmed to date. Ultra-deep HST/WFC3 images reveal an extended envelope starting from {approx}10 kpc and reaching {approx}70 kpc in radius along the semimajor axis. The spectral energy distributions indicate that both its inner component and outer envelope are composed of an old, passively evolving (specific star formation rate <10{sup -4} Gyr{sup -1}) stellar population. The cD galaxy lies on the same mass-size relation as the bulk of quiescent galaxies at similar redshifts. The cD galaxy has a higher stellar mass surface density ({approx}M{sub *}/R{sub 50}{sup 2}) but a similar velocity dispersion ({approx}{radical}(M{sub *}/R{sub 50})) to those of more massive, nearby cDs. If the cD galaxy is one of the progenitors of today's more massive cDs, its size (R{sub 50}) and stellar mass have had to increase on average by factors of 3.4 {+-} 1.1 and 3.3 {+-} 1.3 over the past {approx}8 Gyr, respectively. Such increases in size and stellar mass without being accompanied by significant increases in velocity dispersion are consistent with evolutionary scenarios driven by both major and minor dissipationless (dry) mergers. If such cD envelopes originate from dry mergers, our discovery of even one example proves that some BCGs entered the dry merger phase at epochs earlier than z = 1. Our data match theoretical models which predict that the continuance of dry mergers at z < 1 can result in structures similar to those of massive cD galaxies seen today. Moreover, our discovery is a surprise given that the extreme depth of the HUDF is essential to reveal such an extended cD envelope at z > 1 and, yet, the HUDF covers only a minuscule region of sky ({approx}3.1 Multiplication-Sign 10{sup -8
Observational constraint on spherical inhomogeneity with CMB and local Hubble parameter
Tokutake, Masato; Ichiki, Kiyotomo; Yoo, Chul-Moon
2018-03-01
We derive an observational constraint on a spherical inhomogeneity of the void centered at our position from the angular power spectrum of the cosmic microwave background (CMB) and local measurements of the Hubble parameter. The late time behaviour of the void is assumed to be well described by the so-called Λ-Lemaȋtre-Tolman-Bondi (ΛLTB) solution. Then, we restrict the models to the asymptotically homogeneous models each of which is approximated by a flat Friedmann-Lemaȋtre-Robertson-Walker model. The late time ΛLTB models are parametrized by four parameters including the value of the cosmological constant and the local Hubble parameter. The other two parameters are used to parametrize the observed distance-redshift relation. Then, the ΛLTB models are constructed so that they are compatible with the given distance-redshift relation. Including conventional parameters for the CMB analysis, we characterize our models by seven parameters in total. The local Hubble measurements are reflected in the prior distribution of the local Hubble parameter. As a result of a Markov-Chains-Monte-Carlo analysis for the CMB temperature and polarization anisotropies, we found that the inhomogeneous universe models with vanishing cosmological constant are ruled out as is expected. However, a significant under-density around us is still compatible with the angular power spectrum of CMB and the local Hubble parameter.
A Toy Cosmology Using a Hubble-Scale Casimir Effect
Directory of Open Access Journals (Sweden)
Michael E. McCulloch
2014-02-01
Full Text Available The visible mass of the observable universe agrees with that needed for a flat cosmos, and the reason for this is not known. It is shown that this can be explained by modelling the Hubble volume as a black hole that emits Hawking radiation inwards, disallowing wavelengths that do not fit exactly into the Hubble diameter, since partial waves would allow an inference of what lies outside the horizon. This model of “horizon wave censorship” is equivalent to a Hubble-scale Casimir effect. This incomplete toy model is presented to stimulate discussion. It predicts a minimum mass and acceleration for the observable universe which are in agreement with the observed mass and acceleration, and predicts that the observable universe gains mass as it expands and was hotter in the past. It also predicts a suppression of variation on the largest cosmic scales that agrees with the low-l cosmic microwave background anomaly seen by the Planck satellite.
Building the Hubble Space Telescope
International Nuclear Information System (INIS)
O'dell, C.R.
1989-01-01
The development of the design for the Hubble Space Telescope (HST) is discussed. The HST optical system is described and illustrated. The financial and policy issues related to the development of the HST are considered. The actual construction of the HST optical telescope is examined. Also, consideration is given to the plans for the HST launch
Managing a Product Development Team
Lehtonen, Kenneth E.; Barrett, Larry
2003-01-01
Orbiting 380 miles above the earth, NASA s Hubble Space Telescope (HST) has returned a wealth of scientific data about our universe and galaxies beyond highlighted by spectacular images of the birth and death of stars, colliding galaxies, and other extra-worldly events. Despite its tremendous success for almost two decades, the HST ground support system experienced down-to-earth problems prior to the turn of the century, namely budgetary ones. To keep HST operating efficiently to 201 2 and beyond, the Vision 2000 project was conceived with the primary goal of substantially reducing the costs of operating and maintaining the spacecraft ground systems. Taking advantage of this atypical management opportunity, a set of Product Development Teams (PDTs) were established, whose charter was to re-engineer the ground system, and in doing so, reduce the remaining life-of-mission operating and maintenance costs, while providing improved reliability and increased capabilities.
Images From Hubbles's ACS Tell A Tale Of Two Record-Breaking Galaxy Clusters
2004-01-01
Looking back in time nearly 9 billion years, an international team of astronomers found mature galaxies in a young universe. The galaxies are members of a cluster of galaxies that existed when the universe was only 5 billion years old, or about 35 percent of its present age. This compelling evidence that galaxies must have started forming just after the big bang was bolstered by observations made by the same team of astronomers when they peered even farther back in time. The team found embryonic galaxies a mere 1.5 billion years after the birth of the cosmos, or 10 percent of the universe's present age. The "baby galaxies" reside in a still-developing cluster, the most distant proto-cluster ever found. The Advanced Camera for Surveys (ACS) aboard NASA's Hubble Space Telescope was used to make observations of the massive cluster, RDCS 1252.9-2927, and the proto-cluster, TN J1338-1942. Observations by NASA's Chandra X-ray Observatory yielded the mass and heavy element content of RDCS 1252, the most massive known cluster for that epoch. These observations are part of a coordinated effort by the ACS science team to track the formation and evolution of clusters of galaxies over a broad range of cosmic time. The ACS was built especially for studies of such distant objects. These findings further support observations and theories that galaxies formed relatively early in the history of the cosmos. The existence of such massive clusters in the early universe agrees with a cosmological model wherein clusters form from the merger of many sub-clusters in a universe dominated by cold dark matter. The precise nature of cold dark matter, however, is still not known. The first Hubble study estimated that galaxies in RDCS 1252 formed the bulk of their stars more than 11 billion years ago (at redshifts greater than 3). The results were published in the Oct. 20, 2003 issue of the Astrophysical Journal. The paper's lead author is John Blakeslee of the Johns Hopkins University in
Hubble peers inside a celestial geode
2004-08-01
celestial geode hi-res Size hi-res: 148 Kb Credits: ESA/NASA, Yäel Nazé (University of Liège, Belgium) and You-Hua Chu (University of Illinois, Urbana, USA) Hubble peers inside a celestial geode In this unusual image, the NASA/ESA Hubble Space Telescope captures a rare view of the celestial equivalent of a geode - a gas cavity carved by the stellar wind and intense ultraviolet radiation from a young hot star. Real geodes are handball-sized, hollow rocks that start out as bubbles in volcanic or sedimentary rock. Only when these inconspicuous round rocks are split in half by a geologist, do we get a chance to appreciate the inside of the rock cavity that is lined with crystals. In the case of Hubble's 35 light-year diameter ‘celestial geode’ the transparency of its bubble-like cavity of interstellar gas and dust reveals the treasures of its interior. Low resolution version (JPG format) 148 Kb High resolution version (TIFF format) 1929 Kb Acknowledgment: This image was created with the help of the ESA/ESO/NASA Photoshop FITS Liberator. Real geodes are handball-sized, hollow rocks that start out as bubbles in volcanic or sedimentary rock. Only when these inconspicuous round rocks are split in half by a geologist, do we get a chance to appreciate the inside of the rock cavity that is lined with crystals. In the case of Hubble's 35 light-year diameter ‘celestial geode’ the transparency of its bubble-like cavity of interstellar gas and dust reveals the treasures of its interior. The object, called N44F, is being inflated by a torrent of fast-moving particles (what astronomers call a 'stellar wind') from an exceptionally hot star (the bright star just below the centre of the bubble) once buried inside a cold dense cloud. Compared with our Sun (which is losing mass through the so-called 'solar wind'), the central star in N44F is ejecting more than a 100 million times more mass per second and the hurricane of particles moves much faster at 7 million km per hour
Energy Technology Data Exchange (ETDEWEB)
Labbé, I.; Bouwens, R. J.; Franx, M. [Leiden Observatory, Leiden University, NL-2300 RA Leiden (Netherlands); Oesch, P. A.; Illingworth, G. D.; Magee, D.; González, V. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Carollo, C. M. [Institute for Astronomy, ETH Zurich, 8092 Zurich (Switzerland); Trenti, M. [Kavli Institute for Cosmology and Institute of Astronomy, University of Cambridge, Cambridge (United Kingdom); Van Dokkum, P. G. [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); Stiavelli, M. [Space Telescope Science Institute, Baltimore, MD 21218 (United States)
2013-11-10
Using new ultradeep Spitzer/InfraRed Array Camera (IRAC) photometry from the IRAC Ultra Deep Field program, we investigate the stellar populations of a sample of 63 Y-dropout galaxy candidates at z ∼ 8, only 650 Myr after the big bang. The sources are selected from HST/ACS+WFC3/IR data over the Hubble Ultra Deep Field (HUDF), two HUDF parallel fields, and wide area data over the CANDELS/GOODS-South. The new Spitzer/IRAC data increase the coverage in [3.6] and [4.5] to ∼120h over the HUDF reaching depths of ∼28 (AB,1σ). The improved depth and inclusion of brighter candidates result in direct ≥3σ InfraRed Array Camera (IRAC) detections of 20/63 sources, of which 11/63 are detected at ≥5σ. The average [3.6]-[4.5] colors of IRAC detected galaxies at z ∼ 8 are markedly redder than those at z ∼ 7, observed only 130 Myr later. The simplest explanation is that we witness strong rest-frame optical emission lines (in particular [O III] λλ4959, 5007 + Hβ) moving through the IRAC bandpasses with redshift. Assuming that the average rest-frame spectrum is the same at both z ∼ 7 and z ∼ 8 we estimate a rest-frame equivalent width of contributing 0.56{sup +0.16}{sub -0.11} mag to the [4.5] filter at z ∼ 8. The corresponding W{sub Hα}=430{sup +160}{sub -110} Å implies an average specific star formation rate of sSFR=11{sub -5}{sup +11} Gyr{sup –1} and a stellar population age of 100{sub -50}{sup +100} Myr. Correcting the spectral energy distribution for the contribution of emission lines lowers the average best-fit stellar masses and mass-to-light ratios by ∼3 ×, decreasing the integrated stellar mass density to ρ{sup *}(z=8,M{sub UV}<-18)=0.6{sup +0.4}{sub -0.3}×10{sup 6} M{sub sun} Mpc{sup –3}.
Lubow, S.; Budavári, T.
2013-10-01
We have created an initial catalog of objects observed by the WFPC2 and ACS instruments on the Hubble Space Telescope (HST). The catalog is based on observations taken on more than 6000 visits (telescope pointings) of ACS/WFC and more than 25000 visits of WFPC2. The catalog is obtained by cross matching by position in the sky all Hubble Legacy Archive (HLA) Source Extractor source lists for these instruments. The source lists describe properties of source detections within a visit. The calculations are performed on a SQL Server database system. First we collect overlapping images into groups, e.g., Eta Car, and determine nearby (approximately matching) pairs of sources from different images within each group. We then apply a novel algorithm for improving the cross matching of pairs of sources by adjusting the astrometry of the images. Next, we combine pairwise matches into maximal sets of possible multi-source matches. We apply a greedy Bayesian method to split the maximal matches into more reliable matches. We test the accuracy of the matches by comparing the fluxes of the matched sources. The result is a set of information that ties together multiple observations of the same object. A byproduct of the catalog is greatly improved relative astrometry for many of the HST images. We also provide information on nondetections that can be used to determine dropouts. With the catalog, for the first time, one can carry out time domain, multi-wavelength studies across a large set of HST data. The catalog is publicly available. Much more can be done to expand the catalog capabilities.
A guide to hubble space telescope objects their selection, location, and significance
Chen, James L
2015-01-01
From the authors of "How to Find the Apollo Landing Sites," this is a guide to connecting the view above with the history of recent scientific discoveries from the Hubble Space Telescope. Each selected HST photo is shown with a sky map and a photograph or drawing to illustrate where to find it and how it should appear from a backyard telescope. Here is the casual observer's chance to locate the deep space objects visually, and appreciate the historic Hubble photos in comparison to what is visible from a backyard telescope. HST objects of all types are addressed, from Messier objects, Caldwell objects, and NGC objects, and are arranged in terms of what can be seen during the seasons. Additionally, the reader is given an historical perspective on the work of Edwin Hubble, while locating and viewing the deep space objects that changed astronomy forever. Countless people have seen the amazing photographs taken by the Hubble Space Telescope. But how many people can actually point out where in the sky ...
DEFF Research Database (Denmark)
Mann, R.G.; Oliver, S.J.; Serjeant, S.B.G.
1997-01-01
We discuss the identification of sources detected by the Infrared Space Observatory (ISO) at 6.7 and 15 mu m in the Hubble Deep Field (HDF) region. We conservatively associate ISO sources with objects in existing optical and near-infrared HDF catalogues using the likelihood ratio method, confirming...... these results (and, in one case, clarifying them) with independent visual searches, We find 15 ISO sources to be reliably associated with bright [I-814(AB) HDF, and one with an I-814(AB)=19.9 star, while a further 11 are associated with objects in the Hubble Flanking Fields (10 galaxies...... and one star), Amongst optically bright HDF galaxies, ISO tends to detect luminous, star-forming galaxies at fairly high redshift and with disturbed morphologies, in preference to nearby ellipticals....
Type Ia supernova Hubble residuals and host-galaxy properties
International Nuclear Information System (INIS)
Kim, A. G.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Fleury, M.; Guy, J.; Baltay, C.; Buton, C.; Feindt, U.; Greskovic, P.; Kowalski, M.; Childress, M.; Chotard, N.; Copin, Y.; Gangler, E.
2014-01-01
Kim et al. introduced a new methodology for determining peak-brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spectrophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ± 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at <<1σ, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement of the Hubble residual step with the host mass is 0.045 ± 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch parameters: steps at >2σ significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light-curve width and color around peak (similar to the Δm 15 and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20-30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution.
HUBBLE'S ULTRAVIOLET VIEWS OF NEARBY GALAXIES YIELD CLUES TO EARLY UNIVERSE
2002-01-01
, NGC 3310, shows young and old stars evenly distributed. If this were the case with most galaxies, astronomers would be able to recognize faraway galaxies fairly easily. In most galaxies, however, the stars are segregated by age, making classifying the distant ones more difficult. NGC 3310 is 46 million light-years from Earth in the constellation Ursa Major. The image was taken Sept. 12-13, 2000. The middle image is an example of a tiny, youthful spiral galaxy. ESO 418-008 is representative of the myriad of dwarf galaxies astronomers have seen in deep surveys. These galaxies are much smaller than typical ones like our Milky Way. In this galaxy, the population of stars is more strongly segregated by age. The older stars [red] reside in the center; the younger [blue], in the developing spiral arms. These small, young galaxies may be the building blocks of galaxy formation. ESO 418-008 is 56 million light-years from Earth in the southern constellation Fornax. The image was taken Oct. 10, 2000. The picture at right shows a cosmic collision between two galaxies, UGC 06471 and UGC 06472. These collisions occurred frequently in the early universe, producing galaxies of unusual shapes. The Hubble telescope has spied many such galaxies in the deep field surveys. The ultraviolet images of this galaxy merger suggest the presence of large amounts of dust, which were produced by massive stars that formed before or during this dramatic collision. This dust reddens the starlight in many places, just like a dusty atmosphere reddens the sunset. Studying the effects of this nearby collision could help astronomers explain the peculiar shapes seen in some of the distant galaxies. UGC 06471 and UGC 06472 are 145 million light-years from Earth in the constellation Ursa Major. The image was taken July 11, 2000. Photo credits: NASA, Rogier Windhorst (Arizona State University, Tempe, AZ), and the Hubble mid-UV team
The Hubble Legacy Archive: Data Processing in the Era of AstroDrizzle
Strolger, Louis-Gregory; Hubble Legacy Archive Team, The Hubble Source Catalog Team
2015-01-01
The Hubble Legacy Archive (HLA) expands the utility of Hubble Space Telescope wide-field imaging data by providing high-level composite images and source lists, perusable and immediately available online. The latest HLA data release (DR8.0) marks a fundamental change in how these image combinations are produced, using DrizzlePac tools and Astrodrizzle to reduce geometric distortion and provide improved source catalogs for all publicly available data. We detail the HLA data processing and source list schemas, what products are newly updated and available for WFC3 and ACS, and how these data products are further utilized in the production of the Hubble Source Catalog. We also discuss plans for future development, including updates to WFPC2 products and field mosaics.
Update on the Status of the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope
Hernandez, Svea; Aloisi, A.; Bostroem, K. A.; Cox, C.; Debes, J. H.; DiFelice, A.; Roman-Duval, J.; Hodge, P.; Holland, S.; Lindsay, K.; Lockwood, S. A.; Mason, E.; Oliveira, C. M.; Penton, S. V.; Proffitt, C. R.; Sonnentrucker, P.; Taylor, J. M.; Wheeler, T.
2013-06-01
The Space Telescope Imaging Spectrograph (STIS) has been on orbit for approximately 16 years as one of the 2nd generation instruments on the Hubble Space Telescope (HST). Its operations were interrupted by an electronics failure in 2004, but STIS was successfully repaired in May 2009 during Service Mission 4 (SM4) allowing it to resume science observations. The Instrument team continues to monitor its performance and work towards improving the quality of its products. Here we present updated information on the status of the FUV and NUV MAMA and the CCD detectors onboard STIS and describe recent changes to the STIS calibration pipeline. We also discuss the status of efforts to apply a pixel-based correction for charge transfer inefficiency (CTI) effects to STIS CCD data. These techniques show promise for ameliorating the effects of ongoing radiation damage on the quality of STIS CCD data.
A nuclear data approach for the Hubble constant measurements
Directory of Open Access Journals (Sweden)
Pritychenko Boris
2017-01-01
Full Text Available An extraordinary number of Hubble constant measurements challenges physicists with selection of the best numerical value. The standard U.S. Nuclear Data Program (USNDP codes and procedures have been applied to resolve this issue. The nuclear data approach has produced the most probable or recommended Hubble constant value of 67.2(69 (km/sec/Mpc. This recommended value is based on the last 20 years of experimental research and includes contributions from different types of measurements. The present result implies (14.55 ± 1.51 × 109 years as a rough estimate for the age of the Universe. The complete list of recommended results is given and possible implications are discussed.
Team Learning Ditinjau dari Team Diversity dan Team Efficacy
Pohan, Vivi Gusrini Rahmadani; Ancok, Djamaludin
2010-01-01
This research attempted to observe team learning from the level of team diversity and team efficacy of work teams. This research used an individual level of analysis rather than the group level. The team members measured the level of team diversity, team efficacy and team learning of the teams through three scales, namely team learning scale, team diversity scale, and team efficacy scale. Respondents in this research were the active team members in a company, PT. Alkindo Mitraraya. The total ...
Team Learning Ditinjau dari Team Diversity dan Team Efficacy
Vivi Gusrini Rahmadani Pohan; Djamaludin Ancok
2015-01-01
This research attempted to observe team learning from the level of team diversity and team efficacy of work teams. This research used an individual level of analysis rather than the group level. The team members measured the level of team diversity, team efficacy and team learning of the teams through three scales, namely team learning scale, team diversity scale, and team efficacy scale. Respondents in this research were the active team members in a company, PT. Alkindo Mitraraya. The total ...
Measurement of Hubble constant: non-Gaussian errors in HST Key Project data
Energy Technology Data Exchange (ETDEWEB)
Singh, Meghendra [Dr. A.P.J. Abdul Kalam Technical University, Uttar Pradesh, Lucknow, 226021 India (India); Gupta, Shashikant; Pandey, Ashwini [Amity University Haryana, Gurgaon, Haryana, 122413 India (India); Sharma, Satendra, E-mail: meghendrasingh_db@yahoo.co.in, E-mail: shashikantgupta.astro@gmail.com, E-mail: satyamkashwini@gmail.com, E-mail: ssharma_phy@yahoo.co.uk [Yobe State University, Damaturu, Yobe State (Nigeria)
2016-08-01
Assuming the Central Limit Theorem, experimental uncertainties in any data set are expected to follow the Gaussian distribution with zero mean. We propose an elegant method based on Kolmogorov-Smirnov statistic to test the above; and apply it on the measurement of Hubble constant which determines the expansion rate of the Universe. The measurements were made using Hubble Space Telescope. Our analysis shows that the uncertainties in the above measurement are non-Gaussian.
On the determination of the Hubble constant
International Nuclear Information System (INIS)
Gurzadyan, V.G.; Harutyunyan, V.V.; Kocharyan, A.A.
1990-10-01
The possibility of an alternative determination of the distance scale of the Universe and the Hubble constant based on the numerical analysis of the hierarchical nature of the large scale Universe (galaxies, clusters and superclusters) is proposed. The results of computer experiments performed by means of special numerical algorithms are represented. (author). 9 refs, 7 figs
Hubble Captures Volcanic Eruption Plume From Io
1997-01-01
The Hubble Space Telescope has snapped a picture of a 400-km-high (250-mile-high) plume of gas and dust from a volcanic eruption on Io, Jupiter's large innermost moon.Io was passing in front of Jupiter when this image was taken by the Wide Field and Planetary Camera 2 in July 1996. The plume appears as an orange patch just off the edge of Io in the eight o'clock position, against the blue background of Jupiter's clouds. Io's volcanic eruptions blasts material hundreds of kilometers into space in giant plumes of gas and dust. In this image, material must have been blown out of the volcano at more than 2,000 mph to form a plume of this size, which is the largest yet seen on Io.Until now, these plumes have only been seen by spacecraft near Jupiter, and their detection from the Earth-orbiting Hubble Space Telescope opens up new opportunities for long-term studies of these remarkable phenomena.The plume seen here is from Pele, one of Io's most powerful volcanos. Pele's eruptions have been seen before. In March 1979, the Voyager 1 spacecraft recorded a 300-km-high eruption cloud from Pele. But the volcano was inactive when the Voyager 2 spacecraft flew by Jupiter in July 1979. This Hubble observation is the first glimpse of a Pele eruption plume since the Voyager expeditions.Io's volcanic plumes are much taller than those produced by terrestrial volcanos because of a combination of factors. The moon's thin atmosphere offers no resistance to the expanding volcanic gases; its weak gravity (one-sixth that of Earth) allows material to climb higher before falling; and its biggest volcanos are more powerful than most of Earth's volcanos.This image is a contrast-enhanced composite of an ultraviolet image (2600 Angstrom wavelength), shown in blue, and a violet image (4100 Angstrom wavelength), shown in orange. The orange color probably occurs because of the absorption and/or scattering of ultraviolet light in the plume. This light from Jupiter passes through the plume and is
Enhancing Hubble's vision service missions that expanded our view of the universe
Shayler, David J
2016-01-01
After a 20-year struggle to place a large, sophisticated optical telescope in orbit the Hubble Space Telescope was finally launched in 1990, though its primary mirror was soon found to be flawed. A dramatic mission in 1993 installed corrective optics so that the intended science program could finally begin. Those events are related in a companion to this book, The Hubble Space Telescope: From Concept to Success. Enhancing Hubble’s Vision: Service Missions That Expanded Our View of the Universe tells the story of the four missions between 1997 and 2009 that repaired, serviced and upgraded the instruments on the telescope to maintain its state-of-the-art capabilities. It draws on first hand interviews with those closely involved in the project. The spacewalking skills and experiences gained from maintaining and upgrading Hubble had direct application to the construction of the International Space Station and help with its maintenance. These skills can be applied to future human and robotic satellite servic...
International Nuclear Information System (INIS)
Liu, F. S.; Guo Yicheng; Koo, David C.; Trump, Jonathan R.; Barro, Guillermo; Yesuf, Hassen; Faber, S. M.; Cheung, Edmond; Giavalisco, M.; Cassata, P.; Koekemoer, A. M.; Grogin, Norman A.; Pentericci, L.; Castellano, M.; Mao, Shude; Xia, X. Y.; Hathi, Nimish P.; Huang, Kuang-Han; Kocevski, Dale; McGrath, Elizabeth J.
2013-01-01
We have made a serendipitous discovery of a massive (∼5 × 10 11 M ☉ ) cD galaxy at z = 1.096 in a candidate-rich cluster in the Hubble Ultra Deep Field (HUDF) area of GOODS-South. This brightest cluster galaxy (BCG) is the most distant cD galaxy confirmed to date. Ultra-deep HST/WFC3 images reveal an extended envelope starting from ∼10 kpc and reaching ∼70 kpc in radius along the semimajor axis. The spectral energy distributions indicate that both its inner component and outer envelope are composed of an old, passively evolving (specific star formation rate –4 Gyr –1 ) stellar population. The cD galaxy lies on the same mass-size relation as the bulk of quiescent galaxies at similar redshifts. The cD galaxy has a higher stellar mass surface density (∼M * /R 50 2 ) but a similar velocity dispersion (∼√(M * /R 50 )) to those of more massive, nearby cDs. If the cD galaxy is one of the progenitors of today's more massive cDs, its size (R 50 ) and stellar mass have had to increase on average by factors of 3.4 ± 1.1 and 3.3 ± 1.3 over the past ∼8 Gyr, respectively. Such increases in size and stellar mass without being accompanied by significant increases in velocity dispersion are consistent with evolutionary scenarios driven by both major and minor dissipationless (dry) mergers. If such cD envelopes originate from dry mergers, our discovery of even one example proves that some BCGs entered the dry merger phase at epochs earlier than z = 1. Our data match theoretical models which predict that the continuance of dry mergers at z 1 and, yet, the HUDF covers only a minuscule region of sky (∼3.1 × 10 –8 ). Adding that cDs are rare, our serendipitous discovery hints that such cDs may be more common than expected, perhaps even ubiquitous. Images reaching HUDF depths of more area (especially with cluster BCGs at z > 1) are needed to confirm this conjecture.
Construcción de un diagrama de Hubble: Una herramienta para la Enseñanza de la Astronomía
Directory of Open Access Journals (Sweden)
Giovanni Cardona Rodriguez
2016-06-01
Full Text Available Se presenta una actividad que puede apoyar el trabajo de los docentes que dirigen clubes de Astronomía y quieren abordar el tema de evolución del Universo, ya que se reconstruye la ley de Hubble a partir de la construcción de un Diagrama de Hubble con datos tomados del Sloan Digital Sky Survey (SDSS , del cual se obtiene el valor del parámetro de Hubble y se infiere la expansión del Universo. Esta actividad didáctica permite a los profesores orientar a sus estudiantes por el camino que siguió Hubble para determinar su ley, en este sentido se exponen algunas implicaciones de aplicación de la misma en el contexto de la formación de profesores de física y de los clubes de Astronomía. Construction of a Hubble Diagram: A tool for teaching astronomy This article presents the construction and analysis of an activity that can support the work of teachers who run Astronomy clubs and want to address the issue of evolution of the Universe. Here Hubble's law is reconstructed by reproducing a Hubble diagram with Sloan Digital Sky Survey's (SDSS data, from which the Hubble parameter value is obtained and the expansion of the Universe is inferred. This educational activity allows teachers to guide their students along the path followed by Hubble to determine his law. In this sense some implications of applying the latter are discussed in the context of teacher's training in Physics and Astronomy clubs. Construção de um diagrama de Hubble: Uma ferramenta para ensino de astronomía Se apresenta uma actividade que pode apoiar o trabalho dos professores que dirigem clubes de Astronomia e querem abordar a questão da evolução do Universo, como a lei de Hubble é reconstruída a partir da reprodução de um diagrama de Hubble com os dados tomados do Sloan digital Sky Survey (SDSS, é achado o parâmetro de Hubble e inferida a expansão do universo. Esta actividade educativa permite aos professores orientar seus alunos ao
HUBBLE CAPTURES MERGER BETWEEN QUASAR AND GALAXY
2002-01-01
This NASA Hubble Space Telescope image shows evidence fo r a merger between a quasar and a companion galaxy. This surprising result might require theorists to rethink their explanations for the nature of quasars, the most energetic objects in the universe. The bright central object is the quasar itself, located several billion light-years away. The two wisps on the (left) of the bright central object are remnants of a bright galaxy that have been disrupted by the mutual gravitational attraction between the quasar and the companion galaxy. This provides clear evidence for a merger between the two objects. Since their discovery in 1963, quasars (quasi-stellar objects) have been enigmatic because they emit prodigious amounts of energy from a very compact source. The most widely accepted model is that a quasar is powered by a supermassive black hole in the core of a galaxy. These new observations proved a challenge for theorists as no current models predict the complex quasar interactions unveiled by Hubble. The image was taken with the Wide Field Planetary Camera-2. Credit: John Bahcall, Institute for Advanced Study, NASA.
Hubble Space Telescope: Should NASA Proceed with a Servicing Mission?
National Research Council Canada - National Science Library
Morgan, Daniel
2006-01-01
The National Aeronautics and Space Administration (NASA) estimates that without a servicing mission to replace key components, the Hubble Space Telescope will cease scientific operations in 2008 instead of 2010...
Hartmann wavefront sensing of the corrective optics for the Hubble Space Telescope
Davila, Pam S.; Eichhorn, William L.; Wilson, Mark E.
1994-06-01
There is no doubt that astronomy with the `new, improved' Hubble Space Telescope will significantly advance our knowledge and understanding of the universe for years to come. The Corrective Optics Space Telescope Axial Replacement (COSTAR) was designed to restore the image quality to nearly diffraction limited performance for three of the first generation instruments; the faint object camera, the faint object spectrograph, and the Goddard high resolution spectrograph. Spectacular images have been obtained from the faint object camera after the installation of the corrective optics during the first servicing mission in December of 1993. About 85% of the light in the central core of the corrected image is contained within a circle with a diameter of 0.2 arcsec. This is a vast improvement over the previous 15 to 17% encircled energies obtained before COSTAR. Clearly COSTAR is a success. One reason for the overwhelming success of COSTAR was the ambitious and comprehensive test program conducted by various groups throughout the program. For optical testing of COSTAR on the ground, engineers at Ball Aerospace designed and built the refractive Hubble simulator to produce known amounts of spherical aberration and astigmatism at specific points in the field of view. The design goal for this refractive aberrated simulator (RAS) was to match the aberrations of the Hubble Space Telescope to within (lambda) /20 rms over the field at a wavelength of 632.8 nm. When the COSTAR optics were combined with the RAS optics, the corrected COSTAR output images were produced. These COSTAR images were recorded with a high resolution 1024 by 1024 array CCD camera, the Ball image analyzer (BIA). The image quality criteria used for assessment of COSTAR performance was encircled energy in the COSTAR focal plane. This test with the BIA was very important because it was a direct measurement of the point spread function. But it was difficult with this test to say anything quantitative about the
Directory of Open Access Journals (Sweden)
Roghayeh Alaee
2011-08-01
Full Text Available Introduction: The purpose of the present study was to investigate the prevalence of tobacco, hubble-bubble, alcoholic drinks, and other drugs among Karaj high-school students in 2011. Methods: The research method was a descriptive-sectional study. Participants of this study were 447 girl and boy high-school students of Karaj that were selected by clustering random sampling. For data gathering, drug abuse questionnaire, and risk and protective factors inventory were administered among selected sample. Results: According to the results, 57% of students in this study said that they have had experiences with a kind of drug including tobacco, hubble-bubble, alcoholic drinks, and other drugs at least once in their lives. The study showed the prevalence for soft drugs: hubble-bubble, tobacco, and alcoholic drinks, and for hard drugs ecstasy, opium, hashish, meth, crack, and heroin respectively. Conclusion: Soft drugs including hubble-bubble, tobacco, and alcoholic drinks, are the most common among Karaj high-school students. The prevalence of hard drugs among them is rather low.
Study on team evaluation. Team process model for team evaluation
International Nuclear Information System (INIS)
Sasou Kunihide; Ebisu, Mitsuhiro; Hirose, Ayako
2004-01-01
Several studies have been done to evaluate or improve team performance in nuclear and aviation industries. Crew resource management is the typical example. In addition, team evaluation recently gathers interests in other teams of lawyers, medical staff, accountants, psychiatrics, executive, etc. However, the most evaluation methods focus on the results of team behavior that can be observed through training or actual business situations. What is expected team is not only resolving problems but also training younger members being destined to lead the next generation. Therefore, the authors set the final goal of this study establishing a series of methods to evaluate and improve teams inclusively such as decision making, motivation, staffing, etc. As the first step, this study develops team process model describing viewpoints for the evaluation. The team process is defined as some kinds of power that activate or inactivate competency of individuals that is the components of team's competency. To find the team process, the authors discussed the merits of team behavior with the experienced training instructors and shift supervisors of nuclear/thermal power plants. The discussion finds four team merits and many components to realize those team merits. Classifying those components into eight groups of team processes such as 'Orientation', 'Decision Making', 'Power and Responsibility', 'Workload Management', 'Professional Trust', 'Motivation', 'Training' and 'staffing', the authors propose Team Process Model with two to four sub processes in each team process. In the future, the authors will develop methods to evaluate some of the team processes for nuclear/thermal power plant operation teams. (author)
Buljac, M.; van Woerkom, M.; van Wijngaarden, P.
2013-01-01
This study examines the impact of real-team--as opposed to a team in name only--characteristics (i.e., team boundaries, stability of membership, and task interdependence) on team processes (i.e., team learning and emotional support) and team effectiveness in the long-term care sector. We employed a
Vangrieken, Katrien; Dochy, Filip; Raes, Elisabeth
2016-01-01
This study aimed to investigate team learning in the context of teacher teams in higher vocational education. As teacher teams often do not meet all criteria included in theoretical team definitions, the construct "team entitativity" was introduced. Defined as the degree to which a group of individuals possesses the quality of being a…
Team Leader Structuring for Team Effectiveness and Team Learning in Command-and-Control Teams.
van der Haar, Selma; Koeslag-Kreunen, Mieke; Euwe, Eline; Segers, Mien
2017-04-01
Due to their crucial and highly consequential task, it is of utmost importance to understand the levers leading to effectiveness of multidisciplinary emergency management command-and-control (EMCC) teams. We argue that the formal EMCC team leader needs to initiate structure in the team meetings to support organizing the work as well as facilitate team learning, especially the team learning process of constructive conflict. In a sample of 17 EMCC teams performing a realistic EMCC exercise, including one or two team meetings (28 in sum), we coded the team leader's verbal structuring behaviors (1,704 events), rated constructive conflict by external experts, and rated team effectiveness by field experts. Results show that leaders of effective teams use structuring behaviors more often (except asking procedural questions) but decreasingly over time. They support constructive conflict by clarifying and by making summaries that conclude in a command or decision in a decreasing frequency over time.
Team Leader Structuring for Team Effectiveness and Team Learning in Command-and-Control Teams
van der Haar, Selma; Koeslag-Kreunen, Mieke; Euwe, Eline; Segers, Mien
2017-01-01
Due to their crucial and highly consequential task, it is of utmost importance to understand the levers leading to effectiveness of multidisciplinary emergency management command-and-control (EMCC) teams. We argue that the formal EMCC team leader needs to initiate structure in the team meetings to support organizing the work as well as facilitate team learning, especially the team learning process of constructive conflict. In a sample of 17 EMCC teams performing a realistic EMCC exercise, including one or two team meetings (28 in sum), we coded the team leader’s verbal structuring behaviors (1,704 events), rated constructive conflict by external experts, and rated team effectiveness by field experts. Results show that leaders of effective teams use structuring behaviors more often (except asking procedural questions) but decreasingly over time. They support constructive conflict by clarifying and by making summaries that conclude in a command or decision in a decreasing frequency over time. PMID:28490856
Hubble Space Telescope nickel hydrogen battery system briefing
Nawrocki, David; Saldana, David; Rao, Gopal
1993-01-01
The topics covered are presented in viewgraph form and include the following: the Hubble Space Telescope (HST) Mission; system constraints; battery specification; battery module; simplified block diagram; cell design summary; present status; voltage decay; system depth of discharge; pressure since launch; system capacity; eclipse time vs. trickle charge; capacity test objectives; and capacity during tests.
Townsend, Jacqueline A.; Hansen, Patricia A.; Dever, J. A.; deGroh, K. K.; Banks, B.; Wang, L.; He, C.
1988-01-01
During the Hubble Space Telescope (HST) Second Servicing Mission (SM2), degradation of unsupported Teflon(Registered Trademark) FEP (fluorinated ethylene propylene), used as the outer layer of the multilayer insulation (MLI) blankets, was evident as large cracks on the telescope light shield. A sample of the degraded outer layer was retrieved during the mission and returned to Earth for ground testing and evaluation. The results of the Teflon(Registered Trademark) FEP sample evaluation and additional testing of pristine Teflon(Registered Trademark) FEP led the investigative team to theorize that the HST damage was caused by thermal cycling with deep-layer damage from electron and proton radiation which allowed the propagation of cracks along stress concentrations , and that the damage increased with the combined total dose of electrons, protons, UV and x-rays along with thermal cycling. This paper discusses the testing and evaluation of the retrieved Teflon(Registered Trademark) FEP.
Hubble Space Telescope Image of Omega Nebula
2002-01-01
This sturning image, taken by the newly installed Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope (HST), is an image of the center of the Omega Nebula. It is a hotbed of newly born stars wrapped in colorful blankets of glowing gas and cradled in an enormous cold, dark hydrogen cloud. The region of nebula shown in this photograph is about 3,500 times wider than our solar system. The nebula, also called M17 and the Swan Nebula, resides 5,500 light-years away in the constellation Sagittarius. The Swan Nebula is illuminated by ultraviolet radiation from young, massive stars, located just beyond the upper-right corner of the image. The powerful radiation from these stars evaporates and erodes the dense cloud of cold gas within which the stars formed. The blistered walls of the hollow cloud shine primarily in the blue, green, and red light emitted by excited atoms of hydrogen, nitrogen, oxygen, and sulfur. Particularly striking is the rose-like feature, seen to the right of center, which glows in the red light emitted by hydrogen and sulfur. As the infant stars evaporate the surrounding cloud, they expose dense pockets of gas that may contain developing stars. One isolated pocket is seen at the center of the brightest region of the nebula. Other dense pockets of gas have formed the remarkable feature jutting inward from the left edge of the image. The color image is constructed from four separate images taken in these filters: blue, near infrared, hydrogen alpha, and doubly ionized oxygen. Credit: NASA, H. Ford (JHU), G. Illingworth (USCS/LO), M. Clampin (STScI), G. Hartig (STScI), the ACS Science Team, and ESA.
Jirdeh, Hussein; Straughn, Amber; Smith, Denise Anne; Eisenhamer, Bonnie
2015-08-01
April 24, 2015 marked the 25th anniversary of the launch of the Hubble Space Telescope. In its quarter-century in orbit, the Hubble Space Telescope has transformed the way we understand the Universe, helped us find our place among the stars, and paved the way to incredible advancements in science and technology.In this presentation, we explain how NASA and ESA, including the Space Telescope Science Institute (STScI) and partners, is using the 25th anniversary of Hubble’s launch as a unique opportunity to communicate to students, educators, and the public the significance of the past quarter-century of discovery with the Hubble Space Telescope. We describe the various programs, resources, and experiences we are utilizing to enhancethe public understanding of Hubble’s many contributions to the scientific world. These include educator professional development opportunities, exhibits, events, traditional and social media, and resources for educators (formal k-12, informal, and higher education). We also highlight how we are capitalizing on Hubble’s cultural popularity to make the scientific connection to NASA’s next Great Observatory, the James Webb Space Telescope.This presentation highlights many of the opportunities by which students, educators, and the public are joining in the anniversary activities, both in-person and online. Find out more at hubble25th.org and follow #Hubble25 on social media.
HUBBLE'S PANORAMIC PORTRAIT OF A VAST STAR-FORMING REGION
2002-01-01
NASA's Hubble Space Telescope has snapped a panoramic portrait of a vast, sculpted landscape of gas and dust where thousands of stars are being born. This fertile star-forming region, called the 30 Doradus Nebula, has a sparkling stellar centerpiece: the most spectacular cluster of massive stars in our cosmic neighborhood of about 25 galaxies. The mosaic picture shows that ultraviolet radiation and high-speed material unleashed by the stars in the cluster, called R136 [the large blue blob left of center], are weaving a tapestry of creation and destruction, triggering the collapse of looming gas and dust clouds and forming pillar-like structures that are incubators for nascent stars. The photo offers an unprecedented, detailed view of the entire inner region of 30 Doradus, measuring 200 light-years wide by 150 light-years high. The nebula resides in the Large Magellanic Cloud (a satellite galaxy of the Milky Way), 170,000 light-years from Earth. Nebulas like 30 Doradus are the 'signposts' of recent star birth. High-energy ultraviolet radiation from the young, hot, massive stars in R136 causes the surrounding gaseous material to glow. Previous Hubble telescope observations showed that R136 contains several dozen of the most massive stars known, each about 100 times the mass of the Sun and about 10 times as hot. These stellar behemoths all formed at the same time about 2 million years ago. The stars in R136 are producing intense 'stellar winds' (streams of material traveling at several million miles an hour), which are wreaking havoc on the gas and dust in the surrounding neighborhood. The winds are pushing the gas away from the cluster and compressing the inner regions of the surrounding gas and dust clouds [the pinkish material]. The intense pressure is triggering the collapse of parts of the clouds, producing a new generation of star formation around the central cluster. The new stellar nursery is about 30 to 50 light-years from R136. Most of the stars in the
First results from the Hubble OPAL Program: Jupiter in 2015
Simon, Amy A.; Wong, Michael H.; Orton, Glenn S.
2015-11-01
The Hubble 2020: Outer Planet Atmospheres Legacy (OPAL) program is a Director's Discretionary program designed to generate two yearly global maps for each of the outer planets to enable long term studies of atmospheric color, structure and two-dimensional wind fields. This presentation focuses on Jupiter results from the first year of the campaign. Data were acqured January 19, 2015 with the WFC3/UVIS camera and the F275W, F343N, F395N, F467M, F502N, F547M, F631N, F658N, and F889N filters. Global maps were generated and are publicly available through the High Level Science Products archive: https://archive.stsci.edu/prepds/opal/Using cross-correlation on the global maps, the zonal wind profile was measured between +/- 50 degrees latitude and is in family with Voyager and Cassini era profiles. There are some variations in mid to high latitude wind jet magnitudes, particularly at +40°and -35° planetographic latitude. The Great Red Spot continues to maintain an intense orange coloration, as it did in 2014. However, the interior shows changed structure, including a reduced core and new filamentary features. Finally, a wave not previously seen in Hubble images was also observed and is interpreted as a baroclinic instability with associated cyclone formation near 16° N latitude. A similar feature was observed faintly in Voyager 2 images, and is consistent with the Hubble feature in location and scale.
Hubble's Law Implies Benford's Law for Distances to Galaxies ...
Indian Academy of Sciences (India)
in both time and space, predicts that conformity to Benford's law will improve as more data on distances to galaxies becomes available. Con- versely, with the logical derivation of this law presented here, the recent empirical observations may beviewed as independent evidence of the validity of Hubble's law. Key words.
Remarks on the low value obtained for the Hubble constant
International Nuclear Information System (INIS)
Jaakkola, Toivo
1975-01-01
Some remarks are made on the basis of the data given by Sandage and Tamman, suggesting that these authors have over-estimated the distances to the most luminous galaxies and obtained a value too low for the Hubble constant [fr
An independent determination of the local Hubble constant
Fernández Arenas, David; Terlevich, Elena; Terlevich, Roberto; Melnick, Jorge; Chávez, Ricardo; Bresolin, Fabio; Telles, Eduardo; Plionis, Manolis; Basilakos, Spyros
2018-02-01
The relationship between the integrated H β line luminosity and the velocity dispersion of the ionized gas of H II galaxies and giant H II regions represents an exciting standard candle that presently can be used up to redshifts z ˜ 4. Locally it is used to obtain precise measurements of the Hubble constant by combining the slope of the relation obtained from nearby (z ≤ 0.2) H II galaxies with the zero-point determined from giant H II regions belonging to an `anchor sample' of galaxies for which accurate redshift-independent distance moduli are available. We present new data for 36 giant H II regions in 13 galaxies of the anchor sample that includes the megamaser galaxy NGC 4258. Our data are the result of the first 4 yr of observation of our primary sample of 130 giant H II regions in 73 galaxies with Cepheid determined distances. Our best estimate of the Hubble parameter is 71.0 ± 2.8(random) ± 2.1(systematic) km s- 1Mpc- 1. This result is the product of an independent approach and, although at present less precise than the latest SNIa results, it is amenable to substantial improvement.
On the Luminosity Distance and the Hubble Constant
Yuri Heymann
2013-01-01
By differentiating luminosity distance with respect to time using its standard formula we find that the peculiar velocity is a time varying velocity of light. Therefore, a new definition of the luminosity distance is provided such that the peculiar velocity is equal to c. Using this definition a Hubble constant H0 = 67.3 km s−1 Mpc−1 is obtained from supernovae data.
European team gauges a gamma-ray star
1996-03-01
Italian astrophysicists have pushed the Hubble Space Telescope to the limit of its powers in finding the distance of Geminga, a pointlike object 500 light-years from the Earth. It is the prototype of a novel kind of star, a radio-silent neutron star, which may be much more common in the Universe than previously supposed. Geminga is so weak in visible light that Hubble had to stare at the spot for more than an hour to register it adequately. The object is nevertheless one of the brightest sources of gamma-rays in the sky, and its output of this very energetic form of radiation can now be accurately ganged. Neutron stars, first discovered as radio pulsars in 1967, are fantastic creations of exploding stars, just one step short of a black hole. They are heavier than the Sun yet only about twenty kilometres wide. Made of compressed nuclear matter, they have gravity and magnetic fields many billions of times stronger than on the Earth. With the first direct measurement of the distance of a radio-silent neutron star, astrophysicists can assess Geminga's power and speed of motion. The astronomical task was like judging the width of a one- franc piece in Paris, seen from the distance of Sicily. Geminga's low brightness greatly aggravated the difficulties. Patrizia Caraveo and her colleagues at the Istituto di Fisica Cosmica in Milan arranged for Hubble's wide-field camera (WFPC2) to make its prolonged observations of Geminga three times. Their findings will be published in Astrophysical Journal Letters on 20 April 1996. Caraveo's co-authors are Giovanni Bignami and Roberto Mignani of Milan, and Laurence Taff of Johns Hopkins University, Maryland. The Italians took advantage of the European Space Agency's collaboration with NASA in the Hubble mission, which gives European astronomers privileged access to the Space Telescope. Shifts of millionths of a degree The three sightings of Geminga, made at intervals of six months, revealed small shifts in the position of the faint
The ESA Hubble 15th Anniversary Campaign: A Trans-European collaboration project
Zoulias, Manolis; Christensen, Lars Lindberg; Kornmesser, Martin
2006-08-01
On April 24th 2005, NASA/ESA Hubble Space Telescope had been in orbit for 15 years. The anniversary was celebrated by ESA with the production of an 83 min. scientific movie and a 120 pages book, both titled ``Hubble, 15 years of discovery''. In order to cross language and distribution barriers a network of 16 translators and 22 partners from more than 10 countries was established. The DVD was distributed in approximately 700,000 copies throughout Europe. The project was amongst the largest of its kind with respect to collaboration, distribution and audience impact. It clearly demonstrated how international collaboration can produce effective cross-cultural educational and outreach products for astronomy.
Dynamical friction: The Hubble diagram as a cosmological test
International Nuclear Information System (INIS)
Gunn, J.E.; Tinsley, B.M.
1976-01-01
Effects on the Hubble diagram of the frictional accretion of small cluster galaxies by large ones, to which Ostriker and Tremaine have recently drawn attention, must be accurately determined if the magnitude-redshift relation is to become a viable cosmological test. We find that the process might be detectable through the concomitant change in galaxy colors, but that its effect on the dispersion of magnitudes of first-ranked cluster galaxies would be negligible even if the change in average magnitude is very important. The sign of the effect of accretion on the luminosity observed within a given aperture depends on the structures of the galaxies involved. The size of the effect not only depends sensitively on the galaxy structures, but is also amplified when the relatively recent collapse times of the clusters are taken into account. It is vital to answer the complicated observational and theoretical questions raised by these preliminary calculations, because the Hubble diagram remains the most promising approach to the deceleration parameter q 0 . Local tests of the density of the universe do not give equivalent information
Hubble Space Telescope Image, Supernova Remnant Cassiopeia A
2000-01-01
The colorful streamers that float across the sky in this photo taken by NASA's Hubble Space Telescope (HST) were created by the universe's biggest firecracker, the titanic supernova explosion of a massive star. The light from the exploding star reached Earth 320 years ago, nearly a century before the United States celebrated its birth with a bang. The dead star's shredded remains are called Cassiopeia A, or 'Cas A' for short. Cas A is the youngest known supernova remnant in our Milky Way Galaxy and resides 10,000 light-years away in the constellation Cassiopeia, so the star actually blew up 10,000 years before the light reached Earth in the late 1600s. This HST image of Cas A shows for the first time that the debris is arranged into thousands of small, cooling knots of gas. This material eventually will be recycled into building new generations of stars and planets. Our own Sun and planets are constructed from the debris of supernovae that exploded billions of years ago. This photo shows the upper rim of the super nova remnant's expanding shell. Near the top of the image are dozens of tiny clumps of matter. Each small clump, originally just a small fragment of the star, is tens of times larger than the diameter of our solar system. The colors highlight parts of the debris where chemical elements are glowing. The dark blue fragments, for example, are richest in oxygen; the red material is rich in sulfur. The images were taken with the Wide Field and Planetary Camera 2 in January 2000 and January 2002. Image Credit: NASA and HST team (Stoics/AURA). Acknowledgment: R. Fesen (Darmouth) and J. Morse ( Univ. of Colorado).
Van Hooft, Edwin A J; Van Mierlo, Heleen
2018-01-01
Models of team development have indicated that teams typically engage in task delay during the first stages of the team's life cycle. An important question is to what extent this equally applies to all teams, or whether there is variation across teams in the amount of task delay. The present study introduces the concept of team procrastination as a lens through which we can examine whether teams collectively engage in unplanned, voluntary, and irrational delay of team tasks. Based on theory and research on self-regulation, team processes, and team motivation we developed a conceptual multilevel model of predictors and outcomes of team procrastination. In a sample of 209 student debating teams, we investigated whether and why teams engage in collective procrastination as a team, and what consequences team procrastination has in terms of team member well-being and team performance. The results supported the existence of team procrastination as a team-level construct that has some stability over time. The teams' composition in terms of individual-level trait procrastination, as well as the teams' motivational states (i.e., team learning goal orientation, team performance-approach goal orientation in interaction with team efficacy) predicted team procrastination. Team procrastination related positively to team members' stress levels, especially for those low on trait procrastination. Furthermore, team procrastination had an indirect negative relationship with team performance, through teams' collective stress levels. These findings add to the theoretical understanding of self-regulatory processes of teams, and highlight the practical importance of paying attention to team-level states and processes such as team goal orientation and team procrastination.
Wiseman, Jennifer
2012-01-01
The Hubble Space Telescope has unified the world with a sense of awe and wonder for 2 I years and is currently more scientifically powerful than ever. I will present highlights of discoveries made with the Hubble Space Telescope, including details of planetary weather, star formation, extra-solar planets, colliding galaxies, and a universe expanding with the acceleration of dark energy. I will also present the unique technical challenges and triumphs of this phenomenal observatory, and discuss how our discoveries in the cosmos affect our sense of human unity, significance, and wonder.
The Hubble Space Telescope: UV, Visible, and Near-Infrared Pursuits
Wiseman, Jennifer
2010-01-01
The Hubble Space Telescope continues to push the limits on world-class astrophysics. Cameras including the Advanced Camera for Surveys and the new panchromatic Wide Field Camera 3 which was installed nu last year's successful servicing mission S2N4,o{fer imaging from near-infrared through ultraviolet wavelengths. Spectroscopic studies of sources from black holes to exoplanet atmospheres are making great advances through the versatile use of STIS, the Space Telescope Imaging Spectrograph. The new Cosmic Origins Spectrograph, also installed last year, is the most sensitive UV spectrograph to fly io space and is uniquely suited to address particular scientific questions on galaxy halos, the intergalactic medium, and the cosmic web. With these outstanding capabilities on HST come complex needs for laboratory astrophysics support including atomic and line identification data. I will provide an overview of Hubble's current capabilities and the scientific programs and goals that particularly benefit from the studies of laboratory astrophysics.
A Scientific Revolution: The Hubble and James Webb Space Telescopes
Gardner, Jonathan P.
2010-01-01
Astronomy is going through a scientific revolution, responding to a flood of data from the Hubble Space Telescope, other space missions, and large telescopes on the ground. In this talk, I will discuss some of the important discoveries of the last decade, from dwarf planets in the outer Solar System to the mysterious dark energy that overcomes gravity to accelerate the expansion of the Universe. The next decade will be equally bright with the newly refurbished Hubble and the promise of its successor, the James Webb Space Telescope. An infrared-optimized 6.5m space telescope, Webb is designed to find the first galaxies that formed in the early universe and to peer into the dusty gas clouds where stars and planets are born. With MEMS technology, a deployed primary mirror and a tennis-court sized sunshield, the mission presents many technical challenges. I will describe Webb's scientific goals, its design and recent progress in constructing the observatory. Webb is scheduled for launch in 2014.
Distance to M33 determined from magnitude corrections to Hubble's original cepheid photometry
International Nuclear Information System (INIS)
Sandage, A.
1983-01-01
New photoelectric photometry in Selected Area 45, and transfers from a faint photoelectric sequence adjacent to the south-preceding arm in M33 have been made to the comparison stars for Hubble's Cepheids in M33. Progressive magnitude corrections are required to Hubble's M33 scales, reaching 2.8 mag at the limit of the Mount Wilson 2.5-m Hooker reflector. Hubble's Cepheid light curves have been corrected to the B photoelectric system, and new photometric parameters are given for 35 of his variables. The P-L relation agrees in zero point to within 0.2 mag of the P-L relation from independent data by Sandage and Carlson for 12 new Cepheids in an outlying region of M33. Application of an adopted absolute P-L relation, calibrated by Martin, Warren, and Feast, to these data gives an apparent blue modulus of (m-M)/sup AB//sub M33/ = 25.35, which is 0.67 mag fainter than a previously adopted value, and represents a factor of 4.2 increase of Hubble's earliest distance. Three consequences of this larger apparent distance modulus are (1) the mean absolute magnitude of the first three brightest red supergiants is M/sup max//sub left-angle-bracketV/(3)> = -8.7 rather than approx.-8.0 in M33, complicating but not destroying use of red supergiants as distance indicators, (2) the mean absolute magnitude of the two brightest blue irregular supergiant variables is M/sub left-angle-bracketB/(2)> = -9.95, which is close to the value for the brightest known supergiants in the galaxy, and (3) the absolute magnitude of M33 itself is brighter than heretofore assumed
Making Data Mobile: The Hubble Deep Field Academy iPad app
Eisenhamer, Bonnie; Cordes, K.; Davis, S.; Eisenhamer, J.
2013-01-01
Many school districts are purchasing iPads for educators and students to use as learning tools in the classroom. Educators often prefer these devices to desktop and laptop computers because they offer portability and an intuitive design, while having a larger screen size when compared to smart phones. As a result, we began investigating the potential of adapting online activities for use on Apple’s iPad to enhance the dissemination and usage of these activities in instructional settings while continuing to meet educators’ needs. As a pilot effort, we are developing an iPad app for the “Hubble Deep Field Academy” - an activity that is currently available online and commonly used by middle school educators. The Hubble Deep Field Academy app features the HDF-North image while centering on the theme of how scientists use light to explore and study the universe. It also includes features such as embedded links to vocabulary, images and videos, teacher background materials, and readings about Hubble’s other deep field surveys. It is our goal is to impact students’ engagement in STEM-related activities, while enhancing educators’ usage of NASA data via new and innovative mediums. We also hope to develop and share lessons learned with the E/PO community that can be used to support similar projects. We plan to test the Hubble Deep Field Academy app during the school year to determine if this new activity format is beneficial to the education community.
Quasar Host Galaxies/Neptune Rotation/Galaxy Building Blocks/Hubble Deep Field/Saturn Storm
2001-01-01
Computerized animations simulate a quasar erupting in the core of a normal spiral galaxy, the collision of two interacting galaxies, and the evolution of the universe. Hubble Space Telescope (HST) images show six quasars' host galaxies (including spirals, ellipticals, and colliding galaxies) and six clumps of galaxies approximately 11 billion light years away. A false color time lapse movie of Neptune displays the planet's 16-hour rotation, and the evolution of a storm on Saturn is seen though a video of the planet's rotation. A zoom sequence starts with a ground-based image of the constellation Ursa major and ends with the Hubble Deep Field through progressively narrower and deeper views.
MOVING OBJECTS IN THE HUBBLE ULTRA DEEP FIELD
Energy Technology Data Exchange (ETDEWEB)
Kilic, Mukremin; Gianninas, Alexandros [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Von Hippel, Ted, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: ted.vonhippel@erau.edu [Embry-Riddle Aeronautical University, 600 S. Clyde Morris Blvd., Daytona Beach, FL 32114 (United States)
2013-09-01
We identify proper motion objects in the Hubble Ultra Deep Field (UDF) using the optical data from the original UDF program in 2004 and the near-infrared data from the 128 orbit UDF 2012 campaign. There are 12 sources brighter than I = 27 mag that display >3{sigma} significant proper motions. We do not find any proper motion objects fainter than this magnitude limit. Combining optical and near-infrared photometry, we model the spectral energy distribution of each point-source using stellar templates and state-of-the-art white dwarf models. For I {<=} 27 mag, we identify 23 stars with K0-M6 spectral types and two faint blue objects that are clearly old, thick disk white dwarfs. We measure a thick disk white dwarf space density of 0.1-1.7 Multiplication-Sign 10{sup -3} pc{sup -3} from these two objects. There are no halo white dwarfs in the UDF down to I = 27 mag. Combining the Hubble Deep Field North, South, and the UDF data, we do not see any evidence for dark matter in the form of faint halo white dwarfs, and the observed population of white dwarfs can be explained with the standard Galactic models.
Van Hooft, Edwin A. J.; Van Mierlo, Heleen
2018-01-01
Models of team development have indicated that teams typically engage in task delay during the first stages of the team’s life cycle. An important question is to what extent this equally applies to all teams, or whether there is variation across teams in the amount of task delay. The present study introduces the concept of team procrastination as a lens through which we can examine whether teams collectively engage in unplanned, voluntary, and irrational delay of team tasks. Based on theory and research on self-regulation, team processes, and team motivation we developed a conceptual multilevel model of predictors and outcomes of team procrastination. In a sample of 209 student debating teams, we investigated whether and why teams engage in collective procrastination as a team, and what consequences team procrastination has in terms of team member well-being and team performance. The results supported the existence of team procrastination as a team-level construct that has some stability over time. The teams’ composition in terms of individual-level trait procrastination, as well as the teams’ motivational states (i.e., team learning goal orientation, team performance-approach goal orientation in interaction with team efficacy) predicted team procrastination. Team procrastination related positively to team members’ stress levels, especially for those low on trait procrastination. Furthermore, team procrastination had an indirect negative relationship with team performance, through teams’ collective stress levels. These findings add to the theoretical understanding of self-regulatory processes of teams, and highlight the practical importance of paying attention to team-level states and processes such as team goal orientation and team procrastination. PMID:29674991
Directory of Open Access Journals (Sweden)
Edwin A. J. Van Hooft
2018-04-01
Full Text Available Models of team development have indicated that teams typically engage in task delay during the first stages of the team’s life cycle. An important question is to what extent this equally applies to all teams, or whether there is variation across teams in the amount of task delay. The present study introduces the concept of team procrastination as a lens through which we can examine whether teams collectively engage in unplanned, voluntary, and irrational delay of team tasks. Based on theory and research on self-regulation, team processes, and team motivation we developed a conceptual multilevel model of predictors and outcomes of team procrastination. In a sample of 209 student debating teams, we investigated whether and why teams engage in collective procrastination as a team, and what consequences team procrastination has in terms of team member well-being and team performance. The results supported the existence of team procrastination as a team-level construct that has some stability over time. The teams’ composition in terms of individual-level trait procrastination, as well as the teams’ motivational states (i.e., team learning goal orientation, team performance-approach goal orientation in interaction with team efficacy predicted team procrastination. Team procrastination related positively to team members’ stress levels, especially for those low on trait procrastination. Furthermore, team procrastination had an indirect negative relationship with team performance, through teams’ collective stress levels. These findings add to the theoretical understanding of self-regulatory processes of teams, and highlight the practical importance of paying attention to team-level states and processes such as team goal orientation and team procrastination.
Team Learning and Team Composition in Nursing
Timmermans, Olaf; Van Linge, Roland; Van Petegem, Peter; Elseviers, Monique; Denekens, Joke
2011-01-01
Purpose: This study aims to explore team learning activities in nursing teams and to test the effect of team composition on team learning to extend conceptually an initial model of team learning and to examine empirically a new model of ambidextrous team learning in nursing. Design/methodology/approach: Quantitative research utilising exploratory…
Type I supernovae and angular anisotropy of the Hubble constant
International Nuclear Information System (INIS)
Le Denmat, Gerard; Vigier, J.-P.
1975-01-01
The observation of type I supernovae in distant galaxies yields an homogeneous sample of sources to evaluate their true distance. An examination of their distribution in the sky provides a significant confirmation of the angular anisotropy of the Hubble constant already observed by Rubin, Rubin and Ford [fr
Zhang Wei
2013-01-01
Team learning is a cure for bureaucracy; it facilitates team innovation and team performance. But team learning occurs only when necessary conditions were met. This research focused on differences of team learning influential factors between self-management team and superior-direction team. Four variables were chosen as predictors of team learning though literature review and pilot interview. The 4 variables are team motivation, team trust, team conflict and team leadership. Selected 54 self ...
UVUDF: Ultraviolet Imaging of the Hubble Ultra Deep Field with Wide-Field Camera 3
Teplitz, Harry I.; Rafelski, Marc; Kurczynski, Peter; Bond, Nicholas A.; Grogin, Norman; Koekemoer, Anton M.; Atek, Hakim; Brown, Thomas M.; Coe, Dan; Colbert, James W.; Ferguson, Henry C.; Finkelstein, Steven L.; Gardner, Jonathan P.; Gawiser, Eric; Giavalisco, Mauro; Gronwall, Caryl; Hanish, Daniel J.; Lee, Kyoung-Soo; de Mello, Duilia F.; Ravindranath, Swara; Ryan, Russell E.; Siana, Brian D.; Scarlata, Claudia; Soto, Emmaris; Voyer, Elysse N.; Wolfe, Arthur M.
2013-12-01
We present an overview of a 90 orbit Hubble Space Telescope treasury program to obtain near-ultraviolet imaging of the Hubble Ultra Deep Field using the Wide Field Camera 3 UVIS detector with the F225W, F275W, and F336W filters. This survey is designed to: (1) investigate the episode of peak star formation activity in galaxies at 1 dropouts at redshifts 1.7, 2.1, and 2.7 is largely consistent with the number predicted by published luminosity functions. We also confirm that the image mosaics have sufficient sensitivity and resolution to support the analysis of the evolution of star-forming clumps, reaching 28-29th magnitude depth at 5σ in a 0.''2 radius aperture depending on filter and observing epoch. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are #12534.
Sieweke, Jost; Zhao, B.
2015-01-01
To explore the dynamics involved in team coordination, we examine the impact of team familiarity and team leader experience on team coordination errors (TCEs). We argue that team familiarity has a U-shaped effect on TCEs. We study the moderating effects of team leader prior experience and team
Hubble's View of Little Blue Dots
Kohler, Susanna
2018-02-01
The recent discovery of a new type of tiny, star-forming galaxy is the latest in a zoo of detections shedding light on our early universe. What can we learn from the unique little blue dots found in archival Hubble data?Peas, Berries, and DotsGreen pea galaxies identified by citizen scientists with Galaxy Zoo. [Richard Nowell Carolin Cardamone]As telescope capabilities improve and we develop increasingly deeper large-scale surveys of our universe, we continue to learn more about small, faraway galaxies. In recent years, increasing sensitivity first enabled the detection of green peas luminous, compact, low-mass (10 billion solar masses; compare this to the Milky Ways 1 trillion solar masses!) galaxies with high rates of star formation.Not long thereafter, we discovered galaxies that form stars similarly rapidly, but are even smaller only 330 million solar masses, spanning less than 3,000 light-years in size. These tiny powerhouses were termed blueberries for their distinctive color.Now, scientists Debra and Bruce Elmegreen (of Vassar College and IBM Research Division, respectively) report the discovery of galaxies that have even higher star formation rates and even lower masses: little blue dots.Exploring Tiny Star FactoriesThe Elmegreens discovered these unique galaxies by exploring archival Hubble data. The Hubble Frontier Fields data consist of deep images of six distant galaxy clusters and the parallel fields next to them. It was in the archival data for two Frontier Field Parallels, those for clusters Abell 2744 and MAS J0416.1-2403, that the authors noticed several galaxies that stand out as tiny, bright, blue objects that are nearly point sources.Top: a few examples of the little blue dots recently identified in two Hubble Frontier Field Parallels. Bottom: stacked images for three different groups of little blue dots. [Elmegreen Elmegreen 2017]The authors performed a search through the two Frontier Field Parallels, discovering a total of 55 little blue dots
Studying Galaxy Formation with the Hubble, Spitzer and James Webb Space Telescopes
Gardner, Jonathan P.
2009-01-01
The deepest optical to infrared observations of the universe include the Hubble Deep Fields, the Great Observatories Origins Deep Survey and the recent Hubble Ultra-Deep Field. Galaxies are seen in these surveys at redshifts z greater than 6, less than 1 Gyr after the Big Bang, at the end of a period when light from the galaxies has reionized Hydrogen in the inter-galactic medium. These observations, combined with theoretical understanding, indicate that the first stars and galaxies formed at z greater than 10, beyond the reach of the Hubble and Spitzer Space Telescopes. To observe the first galaxies, NASA is planning the James Webb Space Telescope (JWST), a large (6.5m), cold (less than 50K), infrared-optimized observatory to be launched early in the next decade into orbit around the second Earth-Sun Lagrange point. JWST will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. In addition to JWST's ability to study the formation and evolution of galaxies, I will also briefly review its expected contributions to studies of the formation of stars and planetary systems, and discuss recent progress in constructing the observatory.
Better team management--better team care?
Shelley, P; Powney, B
1994-01-01
Team building should not be a 'bolt-on' extra, it should be a well planned, integrated part of developing teams and assisting their leaders. When asked to facilitate team building by a group of NHS managers we developed a framework which enabled individual members of staff to become more effective in the way they communicated with each other, their teams and in turn within the organization. Facing the challenge posed by complex organizational changes, staff were able to use 3 training days to increase and develop their awareness of the principles of teamwork, better team management, and how a process of leadership and team building could help yield better patient care.
Team responsibility structure and team performance
Doorewaard, J.A.C.M.; Hootegem, G. van; Huys, R.
2002-01-01
The purpose is to analyse the impact of team responsibility (the division of job regulation tasks between team leader and team members) on team performance. It bases an analysis on 36 case studies in The Netherlands which are known to have implemented team‐based work. The case studies were executed
Team cohesion and team success in sport.
Carron, Albert V; Bray, Steven R; Eys, Mark A
2002-02-01
The main aim of this study was to examine the relationship between task cohesiveness and team success in elite teams using composite team estimates of cohesion. A secondary aim was to determine statistically the consistency (i.e. 'groupness') present in team members' perceptions of cohesion. Elite university basketball teams (n = 18) and club soccer teams (n = 9) were assessed for cohesiveness and winning percentages. Measures were recorded towards the end of each team's competitive season. Our results indicate that cohesiveness is a shared perception, thereby providing statistical support for the use of composite team scores. Further analyses indicated a strong relationship between cohesion and success (r = 0.55-0.67). Further research using multi-level statistical techniques is recommended.
A Guided Inquiry on Hubble Plots and the Big Bang
Forringer, Ted
2014-01-01
In our science for non-science majors course "21st Century Physics," we investigate modern "Hubble plots" (plots of velocity versus distance for deep space objects) in order to discuss the Big Bang, dark matter, and dark energy. There are two potential challenges that our students face when encountering these topics for the…
Nickel-hydrogen battery testing for Hubble Space Telescope
Baggett, Randy M.; Whitt, Thomas H.
1989-01-01
The authors identify objectives and provide data from several nickel-hydrogen battery tests designed to evaluate the possibility of launching Ni-H2 batteries on the Hubble Space Telescope (HST). Test results from a 14-cell battery, a 12-cell battery, and a 4-cell pack are presented. Results of a thermal vacuum test to verify the battery-module/bay heat rejection capacity are reported. A 6-battery system simulation breadboard is described, and test results are presented.
The Hubble Space Telescope nickel-hydrogen battery design
Nawrocki, D. E.; Armantrout, J. D.; Standlee, D. J.; Baker, R. C.; Lanier, J. R.
1990-01-01
Details are presented of the HST (Hubble Space Telescope) battery cell, battery package, and module mechanical and electrical designs. Also included are a summary of acceptance, qualification, and vibration tests and thermal vacuum testing. Unique details of battery cell charge retention performance characteristics associated with prelaunch hold conditions are discussed. Special charge control methods to minimize thermal dissipation during pad charging operations are summarized. This module design meets all NASA fracture control requirements for manned missions.
The effect of interacting dark energy on local measurements of the Hubble constant
International Nuclear Information System (INIS)
Odderskov, Io; Baldi, Marco; Amendola, Luca
2016-01-01
In the current state of cosmology, where cosmological parameters are being measured to percent accuracy, it is essential to understand all sources of error to high precision. In this paper we present the results of a study of the local variations in the Hubble constant measured at the distance scale of the Coma Cluster, and test the validity of correcting for the peculiar velocities predicted by gravitational instability theory. The study is based on N-body simulations, and includes models featuring a coupling between dark energy and dark matter, as well as two ΛCDM simulations with different values of σ 8 . It is found that the variance in the local flows is significantly larger in the coupled models, which increases the uncertainty in the local measurements of the Hubble constant in these scenarios. By comparing the results from the different simulations, it is found that most of the effect is caused by the higher value of σ 8 in the coupled cosmologies, though this cannot account for all of the additional variance. Given the discrepancy between different estimates of the Hubble constant in the universe today, cosmological models causing a greater cosmic variance is something that we should be aware of.
The effect of interacting dark energy on local measurements of the Hubble constant
Energy Technology Data Exchange (ETDEWEB)
Odderskov, Io [Department of Physics and Astronomy, University of Aarhus, Ny Munkegade 120, Aarhus C (Denmark); Baldi, Marco [Dipartimento di Fisica e Astronomia, Alma Mater Studiorum Università di Bologna, viale Berti Pichat 6/2, I-40127, Bologna (Italy); Amendola, Luca, E-mail: isho07@phys.au.dk, E-mail: marco.baldi5@unibo.it, E-mail: l.amendola@thphys.uni-heidelberg.de [Institut für Theoretische Physik, Ruprecht-Karls-Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg (Germany)
2016-05-01
In the current state of cosmology, where cosmological parameters are being measured to percent accuracy, it is essential to understand all sources of error to high precision. In this paper we present the results of a study of the local variations in the Hubble constant measured at the distance scale of the Coma Cluster, and test the validity of correcting for the peculiar velocities predicted by gravitational instability theory. The study is based on N-body simulations, and includes models featuring a coupling between dark energy and dark matter, as well as two ΛCDM simulations with different values of σ{sub 8}. It is found that the variance in the local flows is significantly larger in the coupled models, which increases the uncertainty in the local measurements of the Hubble constant in these scenarios. By comparing the results from the different simulations, it is found that most of the effect is caused by the higher value of σ{sub 8} in the coupled cosmologies, though this cannot account for all of the additional variance. Given the discrepancy between different estimates of the Hubble constant in the universe today, cosmological models causing a greater cosmic variance is something that we should be aware of.
Improving Care Teams' Functioning: Recommendations from Team Science.
Fiscella, Kevin; Mauksch, Larry; Bodenheimer, Thomas; Salas, Eduardo
2017-07-01
Team science has been applied to many sectors including health care. Yet there has been relatively little attention paid to the application of team science to developing and sustaining primary care teams. Application of team science to primary care requires adaptation of core team elements to different types of primary care teams. Six elements of teams are particularly relevant to primary care: practice conditions that support or hinder effective teamwork; team cognition, including shared understanding of team goals, roles, and how members will work together as a team; leadership and coaching, including mutual feedback among members that promotes teamwork and moves the team closer to achieving its goals; cooperation supported by an emotionally safe climate that supports expression and resolution of conflict and builds team trust and cohesion; coordination, including adoption of processes that optimize efficient performance of interdependent activities among team members; and communication, particularly regular, recursive team cycles involving planning, action, and debriefing. These six core elements are adapted to three prototypical primary care teams: teamlets, health coaching, and complex care coordination. Implementation of effective team-based models in primary care requires adaptation of core team science elements coupled with relevant, practical training and organizational support, including adequate time to train, plan, and debrief. Training should be based on assessment of needs and tasks and the use of simulations and feedback, and it should extend to live action. Teamlets represent a potential launch point for team development and diffusion of teamwork principles within primary care practices. Copyright © 2017 The Joint Commission. Published by Elsevier Inc. All rights reserved.
Han-Ping Fung
2014-01-01
Today, more and more project teams are formed to achieve organizational objectives as organizations generally recognized the importance and benefits of project teams. There is a compelling reason to study what are the team outcome factors that can predict project team effectiveness as it is unclear whether these team outcome factors can yield the same result in project setting whereby there is resource and time constraint compare to normal work teams which are ongoing and operational in natur...
Observational constraints on Hubble parameter in viscous generalized Chaplygin gas
Thakur, P.
2018-04-01
Cosmological model with viscous generalized Chaplygin gas (in short, VGCG) is considered here to determine observational constraints on its equation of state parameters (in short, EoS) from background data. These data consists of H(z)-z (OHD) data, Baryonic Acoustic Oscillations peak parameter, CMB shift parameter and SN Ia data (Union 2.1). Best-fit values of the EoS parameters including present Hubble parameter (H0) and their acceptable range at different confidence limits are determined. In this model the permitted range for the present Hubble parameter and the transition redshift (zt) at 1σ confidence limits are H0= 70.24^{+0.34}_{-0.36} and zt=0.76^{+0.07}_{-0.07} respectively. These EoS parameters are then compared with those of other models. Present age of the Universe (t0) have also been determined here. Akaike information criterion and Bayesian information criterion for the model selection have been adopted for comparison with other models. It is noted that VGCG model satisfactorily accommodates the present accelerating phase of the Universe.
Hubble Space Telescope electrical power system
Whitt, Thomas H.; Bush, John R., Jr.
1990-01-01
The Hubble Space Telescope (HST) electrical power system (EPS) is supplying between 2000 and 2400 W of continuous power to the electrical loads. The major components of the EPS are the 5000-W back surface field reflector solar array, the six nickel-hydrogen (NiH2) 22-cell 88-Ah batteries, and the charge current controllers, which, in conjunction with the flight computer, control battery charging. The operation of the HST EPS and the results of the HST NiH2 six-battery test are discussed, and preliminary flight data are reviewed. The HST NiH2 six-battery test is a breadboard of the HST EPS on test at Marshall Space Flight Center.
Making Teamwork Work: Team Knowledge for Team Effectiveness.
Guchait, Priyanko; Lei, Puiwa; Tews, Michael J
2016-01-01
This study examined the impact of two types of team knowledge on team effectiveness. The study assessed the impact of taskwork knowledge and teamwork knowledge on team satisfaction and performance. A longitudinal study was conducted with 27 service-management teams involving 178 students in a real-life restaurant setting. Teamwork knowledge was found to impact both team outcomes. Furthermore, team learning behavior was found to mediate the relationships between teamwork knowledge and team outcomes. Educators and managers should therefore ensure these types of knowledge are developed in teams along with learning behavior for maximum effectiveness.
Constraining the evolution of the Hubble Parameter using cosmic chronometers
Dickinson, Hugh
2017-08-01
Substantial investment is being made in space- and ground-based missions with the goal of revealing the nature of the observed cosmic acceleration. This is one of the most important unsolved problems in cosmology today.We propose here to constrain the evolution of the Hubble parameter [H(z)] between 1.3 fundamental nature of dark energy.
"HUBBLE, the astronomer, the telescope, the results"
CERN. Geneva
2011-01-01
The fundamental discoveries made by Edwin Hubble in the first quarter of the last century will be presented. The space telescope bearing his name will be introduced, as well as the strategy put in place by NASA and the European Space Agency for its operation and its maintenance on-orbit. The personal experience of the speaker having participated in two of five servicing mission will be exposed and illustrated by pictures taken on-orbit. Finally, the main results obtained by the orbital observatory will be presented, in particular the ones related to the large scale structure of the Universe and its early history
Groups Meet . . . Teams Improve: Building Teams That Learn
Hillier, Janet; Dunn-Jensen, Linda M.
2013-01-01
Although most business students participate in team-based projects during undergraduate or graduate course work, the team experience does not always teach team skills or capture the team members' potential: Students complete the task at hand but the explicit process of becoming a team is often not learned. Drawing from organizational learning…
Torrente, Pedro; Salanova, Marisa; Llorens, Susana; Schaufeli, Wilmar B
2012-02-01
In this study we analyze the mediating role of team work engagement between team social resources (i.e., supportive team climate, coordination, teamwork), and team performance (i.e., in-role and extra-role performance) as predicted by the Job Demands-Resources Model. Aggregated data of 533 employees nested within 62 teams and 13 organizations were used, whereas team performance was assessed by supervisor ratings. Structural equation modeling revealed that, as expected, team work engagement plays a mediating role between social resources perceived at the team level and team performance as assessed by the supervisor.
Hubble Images Reveal Jupiter's Auroras
1996-01-01
These images, taken by the Hubble Space Telescope, reveal changes in Jupiter's auroral emissions and how small auroral spots just outside the emission rings are linked to the planet's volcanic moon, Io. The images represent the most sensitive and sharply-detailed views ever taken of Jovian auroras.The top panel pinpoints the effects of emissions from Io, which is about the size of Earth's moon. The black-and-white image on the left, taken in visible light, shows how Io and Jupiter are linked by an invisible electrical current of charged particles called a 'flux tube.' The particles - ejected from Io (the bright spot on Jupiter's right) by volcanic eruptions - flow along Jupiter's magnetic field lines, which thread through Io, to the planet's north and south magnetic poles. This image also shows the belts of clouds surrounding Jupiter as well as the Great Red Spot.The black-and-white image on the right, taken in ultraviolet light about 15 minutes later, shows Jupiter's auroral emissions at the north and south poles. Just outside these emissions are the auroral spots. Called 'footprints,' the spots are created when the particles in Io's 'flux tube' reach Jupiter's upper atmosphere and interact with hydrogen gas, making it fluoresce. In this image, Io is not observable because it is faint in the ultraviolet.The two ultraviolet images at the bottom of the picture show how the auroral emissions change in brightness and structure as Jupiter rotates. These false-color images also reveal how the magnetic field is offset from Jupiter's spin axis by 10 to 15 degrees. In the right image, the north auroral emission is rising over the left limb; the south auroral oval is beginning to set. The image on the left, obtained on a different date, shows a full view of the north aurora, with a strong emission inside the main auroral oval.The images were taken by the telescope's Wide Field and Planetary Camera 2 between May 1994 and September 1995.This image and other images and data
Team Learning Beliefs and Behaviours in Response Teams
Boon, Anne; Raes, Elisabeth; Kyndt, Eva; Dochy, Filip
2013-01-01
Purpose: Teams, teamwork and team learning have been the subject of many research studies over the last decades. This article aims at investigating and confirming the Team Learning Beliefs and Behaviours (TLB&B) model within a very specific population, i.e. police and firemen teams. Within this context, the paper asks whether the team's…
Feinberg, Mark E; Kim, Ji-Yeon; Greenberg, Mark T
2008-11-01
The predictors and correlates of positive functioning among community prevention teams have been examined in a number of research studies; however, the role of personality has been neglected. In this study, we examined whether team member and leader personality dimensions assessed at the time of team formation predicted local prevention team functioning 2.5-3.5 years later. Participants were 159 prevention team members in 14 communities participating in the PROSPER study of prevention program dissemination. Three aspects of personality, aggregated at the team level, were examined as predictors: Openness to Experience, Conscientiousness, and Agreeableness. A series of multivariate regression analyses were performed that accounted for the interdependency of five categories of team functioning. Results showed that average team member Openness was negatively, and Conscientiousness was positively linked to team functioning. The findings have implications for decisions about the level and nature of technical assistance support provided to community prevention teams.
The Hubble series: convergence properties and redshift variables
International Nuclear Information System (INIS)
Cattoen, Celine; Visser, Matt
2007-01-01
In cosmography, cosmokinetics and cosmology, it is quite common to encounter physical quantities expanded as a Taylor series in the cosmological redshift z. Perhaps the most well-known exemplar of this phenomenon is the Hubble relation between distance and redshift. However, we now have considerable high-z data available; for instance, we have supernova data at least back to redshift z ∼ 1.75. This opens up the theoretical question as to whether or not the Hubble series (or more generally any series expansion based on the z-redshift) actually converges for large redshift. Based on a combination of mathematical and physical reasonings, we argue that the radius of convergence of any series expansion in z is less than or equal to 1, and that z-based expansions must break down for z > 1, corresponding to a universe less than half of its current size. Furthermore, we shall argue on theoretical grounds for the utility of an improved parametrization y = z/(1 + z). In terms of the y-redshift, we again argue that the radius of convergence of any series expansion in y is less than or equal to 1, so that y-based expansions are likely to be good all the way back to the big bang (y = 1), but that y-based expansions must break down for y < -1, now corresponding to a universe more than twice its current size
The variance of the locally measured Hubble parameter explained with different estimators
DEFF Research Database (Denmark)
Odderskov, Io Sandberg Hess; Hannestad, Steen; Brandbyge, Jacob
2017-01-01
We study the expected variance of measurements of the Hubble constant, H0, as calculated in either linear perturbation theory or using non-linear velocity power spectra derived from N-body simulations. We compare the variance with that obtained by carrying out mock observations in the N......-body simulations, and show that the estimator typically used for the local Hubble constant in studies based on perturbation theory is different from the one used in studies based on N-body simulations. The latter gives larger weight to distant sources, which explains why studies based on N-body simulations tend...... to obtain a smaller variance than that found from studies based on the power spectrum. Although both approaches result in a variance too small to explain the discrepancy between the value of H0 from CMB measurements and the value measured in the local universe, these considerations are important in light...
The Hubble Tarantula Treasury Project
Sabbi, Elena; Lennon, D. J.; Anderson, J.; Van Der Marel, R. P.; Aloisi, A.; Boyer, M. L.; Cignoni, M.; De Marchi, G.; de Mink, S. E.; Evans, C. J.; Gallagher, J. S.; Gordon, K. D.; Gouliermis, D.; Grebel, E.; Koekemoer, A. M.; Larsen, S. S.; Panagia, N.; Ryon, J. E.; Smith, L. J.; Tosi, M.; Zaritsky, D. F.
2014-01-01
The Tarantula Nebula (a.k.a. 30 Doradus) in the Large Magellanic Cloud is one of the most famous objects in astronomy, with first astronomical references being more than 150 years old. Today the Tarantula Nebula and its ionizing cluster R136 are considered one of the few known starburst regions in the Local Group and an ideal test bed to investigate the temporal and spatial evolution of a prototypical starburst on a sub-cluster scale. The Hubble Tarantula Treasury Project (HTTP) is a panchromatic imaging survey of the stellar populations and ionized gas in the Tarantula Nebula that reaches into the sub-solar mass regime (eBook that explains how stars form and evolve using images from HTTP. The eBook utilizes emerging technology that works in conjunction with the built-in accessibility features in the Apple iPad to allow totally blind users to interactively explore complex astronomical images.
Astronaut Anna Fisher in NBS Training For Hubble Space Telescope
1980-01-01
The Hubble Space Telescope (HST) is a cooperative program of the European Space Agency (ESA) and the National Aeronautical and Space Administration (NASA) to operate a long-lived space-based observatory. It was the flagship mission of NASA's Great Observatories program. The HST program began as an astronomical dream in the 1940s. During the 1970s and 1980s, the HST was finally designed and built becoming operational in the 1990s. The HST was deployed into a low-Earth orbit on April 25, 1990 from the cargo bay of the Space Shuttle Discovery (STS-31). The design of the HST took into consideration its length of service and the necessity of repairs and equipment replacement by making the body modular. In doing so, subsequent shuttle missions could recover the HST, replace faulty or obsolete parts and be re-released. Marshall Space Flight Center's (MSFC's) Neutral Buoyancy Simulator (NBS) served as the test center for shuttle astronauts training for Hubble related missions. Shown is astronaut Anna Fisher training on a mock-up of a modular section of the HST for an axial scientific instrument change out.
Conway Hughston, Veronica
Since 1996 ABET has mandated that undergraduate engineering degree granting institutions focus on learning outcomes such as professional skills (i.e. solving unstructured problems and working in teams). As a result, engineering curricula were restructured to include team based learning---including team charters. Team charters were diffused into engineering education as one of many instructional activities to meet the ABET accreditation mandates. However, the implementation and execution of team charters into engineering team based classes has been inconsistent and accepted without empirical evidence of the consequences. The purpose of the current study was to investigate team effectiveness, operationalized as team viability, as an outcome of team charter implementation in an undergraduate engineering team based design course. Two research questions were the focus of the study: a) What is the relationship between team charter quality and viability in engineering student teams, and b) What is the relationship among team charter quality, teamwork mental model similarity, and viability in engineering student teams? Thirty-eight intact teams, 23 treatment and 15 comparison, participated in the investigation. Treatment teams attended a team charter lecture, and completed a team charter homework assignment. Each team charter was assessed and assigned a quality score. Comparison teams did not join the lecture, and were not asked to create a team charter. All teams completed each data collection phase: a) similarity rating pretest; b) similarity posttest; and c) team viability survey. Findings indicate that team viability was higher in teams that attended the lecture and completed the charter assignment. Teams with higher quality team charter scores reported higher levels of team viability than teams with lower quality charter scores. Lastly, no evidence was found to support teamwork mental model similarity as a partial mediator of the team charter quality on team viability
E.A.J. van Hooft (Edwin); H. van Mierlo (Heleen)
2018-01-01
textabstractModels of team development have indicated that teams typically engage in task delay during the first stages of the team's life cycle. An important question is to what extent this equally applies to all teams, or whether there is variation across teams in the amount of task delay. The
On teams, teamwork, and team performance: discoveries and developments.
Salas, Eduardo; Cooke, Nancy J; Rosen, Michael A
2008-06-01
We highlight some of the key discoveries and developments in the area of team performance over the past 50 years, especially as reflected in the pages of Human Factors. Teams increasingly have become a way of life in many organizations, and research has kept up with the pace. We have characterized progress in the field in terms of eight discoveries and five challenges. Discoveries pertain to the importance of shared cognition, the measurement of shared cognition, advances in team training, the use of synthetic task environments for research, factors influencing team effectiveness, models of team effectiveness, a multidisciplinary perspective, and training and technological interventions designed to improve team effectiveness. Challenges that are faced in the coming decades include an increased emphasis on team cognition; reconfigurable, adaptive teams; multicultural influences; and the need for naturalistic study and better measurement. Work in human factors has contributed significantly to the science and practice of teams, teamwork, and team performance. Future work must keep pace with the increasing use of teams in organizations. The science of teams contributes to team effectiveness in the same way that the science of individual performance contributes to individual effectiveness.
Team player styles, team design variables and team work effectiveness in Egypt
El-Kot, Ghada Awed Hassan
2001-01-01
The literature has revealed few studies of management in Arab countries in general and particularly in Egypt. Many Egyptian organisations implemented the team concept a number of years ago, however, there do not appear to be any studies investicitaýt inc",D team work effectiveness in Egypt. The literature review and the findings of a pilot study emphasised the need for empirical research in team work in Egypt. Team effectiveness models are examined in order to identify the fact...
Solar system anomalies: Revisiting Hubble's law
Plamondon, R.
2017-12-01
This paper investigates the impact of a new metric recently published [R. Plamondon and C. Ouellet-Plamondon, in On Recent Developments in Theoretical and Experimental General Relativity, Astrophysics, and Relativistic Field Theories, edited by K. Rosquist, R. T. Jantzen, and R. Ruffini (World Scientific, Singapore, 2015), p. 1301] for studying the space-time geometry of a static symmetric massive object. This metric depends on a complementary error function (erfc) potential that characterizes the emergent gravitation field predicted by the model. This results in two types of deviations as compared to computations made on the basis of a Newtonian potential: a constant and a radial outcome. One key feature of the metric is that it postulates the existence of an intrinsic physical constant σ , the massive object-specific proper length that scales measurements in its surroundings. Although σ must be evaluated experimentally, we use a heuristic to estimate its value and point out some latent relationships between the Hubble constant, the secular increase in the astronomical unit, and the Pioneers delay. Indeed, highlighting the systematic errors that emerge when the effect of σ is neglected, one can link the Hubble constant H 0 to σ Sun and the secular increase V AU to σ Earth . The accuracy of the resulting numerical predictions, H 0 = 74 . 42 ( 0 . 02 ) ( km / s ) / Mpc and V AU ≅ 7.8 cm yr-1 , calls for more investigations of this new metric by specific experts. Moreover, we investigate the expected impacts of the new metric on the flyby anomalies, and we revisit the Pioneers delay. It is shown that both phenomena could be partly taken into account within the context of this unifying paradigm, with quite accurate numerical predictions. A correction for the osculating asymptotic velocity at the perigee of the order of 10 mm/s and an inward radial acceleration of 8 . 34 × 10 - 10 m / s 2 affecting the Pioneer ! space crafts could be explained by this new model.
National Highway Traffic Safety Administration (DOT), Washington, DC.
This document presents materials covering the television campaign against drunk driving called "TEAM" (Techniques for Effective Alcohol Management). It is noted that TEAM's purpose is to promote effective alcohol management in public facilities and other establishments that serve alcoholic beverages. TEAM sponsors are listed, including…
Team dynamics within quality improvement teams: a scoping review.
Rowland, Paula; Lising, Dean; Sinclair, Lynne; Baker, G Ross
2018-03-31
This scoping review examines what is known about the processes of quality improvement (QI) teams, particularly related to how teams impact outcomes. The aim is to provide research-informed guidance for QI leaders and to inform future research questions. Databases searched included: MedLINE, EMBASE, CINAHL, Web of Science and SCOPUS. Eligible publications were written in English, published between 1999 and 2016. Articles were included in the review if they examined processes of the QI team, were related to healthcare QI and were primary research studies. Studies were excluded if they had insufficient detail regarding QI team processes. Descriptive detail extracted included: authors, geographical region and health sector. The Integrated (Health Care) Team Effectiveness Model was used to synthesize findings of studies along domains of team effectiveness: task design, team process, psychosocial traits and organizational context. Over two stages of searching, 4813 citations were reviewed. Of those, 48 full-text articles are included in the synthesis. This review demonstrates that QI teams are not immune from dysfunction. Further, a dysfunctional QI team is not likely to influence practice. However, a functional QI team alone is unlikely to create change. A positive QI team dynamic may be a necessary but insufficient condition for implementing QI strategies. Areas for further research include: interactions between QI teams and clinical microsystems, understanding the role of interprofessional representation on QI teams and exploring interactions between QI team task, composition and process.
Increasing Student-Learning Team Effectiveness with Team Charters
Hunsaker, Phillip; Pavett, Cynthia; Hunsaker, Johanna
2011-01-01
Because teams are a ubiquitous part of most organizations today, it is common for business educators to use team assignments to help students experientially learn about course concepts and team process. Unfortunately, students frequently experience a number of problems during team assignments. The authors describe the results of their research and…
Effects of team emotional authenticity on virtual team performance
Directory of Open Access Journals (Sweden)
Catherine E Connelly
2016-08-01
Full Text Available Members of virtual teams lack many of the visual or auditory cues that are usually used as the basis for impressions about fellow team members. We focus on the effects of the impressions formed in this context, and use social exchange theory to understand how these impressions affect team performance. Our pilot study, using content analysis (n = 191 students, suggested that most individuals believe that they can assess others’ emotional authenticity in online settings by focusing on the content and tone of the messages. Our quantitative study examined the effects of these assessments. Structural equation modeling (SEM analysis (n = 81 student teams suggested that team-level trust and teamwork behaviors mediate the relationship between team emotional authenticity and team performance, and illuminate the importance of team emotional authenticity for team processes and outcomes.
Dynamical interpretation of the Hubble sequence of galaxies
Energy Technology Data Exchange (ETDEWEB)
Dallaporta, N; Secco, L [Padua Univ. (Italy). Istituto di Astronomia
1977-08-01
Brosche (1970) has proposed a theory in which the energy loss due to collisions among gas clouds contained in a galaxy constitutes the driving mechanism for its evolution, through virial equilibrium states, which, from an initial spherical shape, makes it to contract towards an elongated form; moreover, the value of the total angular momentum, assumed as given by uniform rotation, is assumed to determine the galaxy type on the Hubble sequence and to influence strongly the contraction time from the initial spherical to the final flat configuration. The authors modify Brosche's scheme by assuming as models the rotating polytropes of Chandrasekhar and Lebovitz with variable density from centre to border. As a consequence of this change, centrifugal shedding of matter is attained at the equator of the contracting ellipsoid for a configuration with an axial ratio different from zero, so that, hereafter, a flat disk is formed surrounding the internal bulge, with a decreasing overall eccentricity; the rotation curve assumes then an aspect qualitatively similar to the one observed for spiral galaxies. The feedback of star formation which, by exhausting the material of the gas clouds, is able to stop the driving mechanism of evolution before the final flat stage is attained has also been considered at several positions according to the value of the angular momentum. Numerical calculations seem to indicate that one can obtain in this way, by varying the angular momentum and the initial number of clouds, different galaxy types (elliptical, lenticular, spiral) resembling those of the Hubble sequence.
International Nuclear Information System (INIS)
Guo, Rui-Yun; Zhang, Xin
2016-01-01
The nature of dark energy affects the Hubble expansion rate (namely, the expansion history) H(z) by an integral over w(z). However, the usual observables are the luminosity distances or the angular diameter distances, which measure the distance.redshift relation. Actually, the property of dark energy affects the distances (and the growth factor) by a further integration over functions of H(z). Thus, the direct measurements of the Hubble parameter H(z) at different redshifts are of great importance for constraining the properties of dark energy. In this paper, we show how the typical dark energy models, for example, the ΛCDM, wCDM, CPL, and holographic dark energy models, can be constrained by the current direct measurements of H(z) (31 data used in total in this paper, covering the redshift range of z @ element of [0.07, 2.34]). In fact, the future redshift-drift observations (also referred to as the Sandage-Loeb test) can also directly measure H(z) at higher redshifts, covering the range of z @ element of [2, 5]. We thus discuss what role the redshift-drift observations can play in constraining dark energy with the Hubble parameter measurements. We show that the constraints on dark energy can be improved greatly with the H(z) data from only a 10-year observation of redshift drift. (orig.)
Measuring Team Learning Behaviours through Observing Verbal Team Interaction
Raes, Elisabeth; Boon, Anne; Kyndt, Eva; Dochy, Filip
2015-01-01
Purpose: This study aims to explore, as an answer to the observed lack of knowledge about actual team learning behaviours, the characteristics of the actual observed basic team learning behaviours and facilitating team learning behaviours more in-depth of three project teams. Over time, team learning in an organisational context has been…
Midthaug, Mari Bratterud
2017-01-01
The purpose of this thesis is to explore the relationship between team size (number of team members) and team performance in management teams. There is a lack of empirical research exploring the potential links between these two elements within management teams. Further, little attention has been paid to potential mechanisms affecting this relationship. In this study, team psychological safety has been examined as a potential mediator in the size-performance relationship, hypothesizing that t...
DEFF Research Database (Denmark)
Gilliland, Ronald L.; McCullough, Peter R.; Nelan, Edmund P.
2011-01-01
light curve. Using the density constraint from asteroseismology, and stellar evolution modeling results in M * = 1.285 ± 0.026 M sun, R * = 1.507 ± 0.012 R sun, and a stellar age of 3.2 ± 0.3 Gyr. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science......Observations conducted with the Fine Guidance Sensor on the Hubble Space Telescope (HST) providing high cadence and precision time-series photometry were obtained over 10 consecutive days in 2008 December on the host star of the transiting exoplanet HD 17156b. During this time, 1.0 × 1012 photons...... Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555....
Leading Teams of Leaders: What Helps Team Member Learning?
Higgins, Monica; Young, Lissa; Weiner, Jennie; Wlodarczyk, Steven
2010-01-01
School districts are moving toward a new form of management in which superintendents need to form and nurture leadership teams. A study of 25 such teams in Connecticut suggests that a team's effectiveness is maximized when the team members are coached by other team members, not the superintendent, and when they are coached on task-related…
A Project Team: a Team or Just a Group?
Directory of Open Access Journals (Sweden)
Kateřina
2014-06-01
Full Text Available This paper deals with issues related to work in either teams or groups. The theoretical part discusses a team and a group with regards to its definition, classification and basic distinction, brings in more on the typology of team roles, personality assessment and sociometric methods. The analytical part tests the project (work team of a medical center represented in terms of personality and motivational types, team roles and interpersonal team relations concerning the willingness of cooperation and communication. The main objective of this work is to verify the validity of the assumptions that the analyzed team represents a very disparate group as for its composition from the perspective of personality types, types of motivation, team roles and interpersonal relations in terms of the willingness of cooperation and communication. A separate output shall focus on sociometric investigation of those team members where willingness to work together and communicate is based on the authors’ assumption of tight interdependence.
Labbé, I.; Oesch, P. A.; Bouwens, R. J.; Illingworth, G. D.; Magee, D.; González, V.; Carollo, C. M.; Franx, M.; Trenti, M.; van Dokkum, P. G.; Stiavelli, M.
2013-11-01
Using new ultradeep Spitzer/InfraRed Array Camera (IRAC) photometry from the IRAC Ultra Deep Field program, we investigate the stellar populations of a sample of 63 Y-dropout galaxy candidates at z ~ 8, only 650 Myr after the big bang. The sources are selected from HST/ACS+WFC3/IR data over the Hubble Ultra Deep Field (HUDF), two HUDF parallel fields, and wide area data over the CANDELS/GOODS-South. The new Spitzer/IRAC data increase the coverage in [3.6] and [4.5] to ~120h over the HUDF reaching depths of ~28 (AB,1σ). The improved depth and inclusion of brighter candidates result in direct >=3σ InfraRed Array Camera (IRAC) detections of 20/63 sources, of which 11/63 are detected at >=5σ. The average [3.6]-[4.5] colors of IRAC detected galaxies at z ~ 8 are markedly redder than those at z ~ 7, observed only 130 Myr later. The simplest explanation is that we witness strong rest-frame optical emission lines (in particular [O III] λλ4959, 5007 + Hβ) moving through the IRAC bandpasses with redshift. Assuming that the average rest-frame spectrum is the same at both z ~ 7 and z ~ 8 we estimate a rest-frame equivalent width of {W}_{[O\\,\\scriptsize{III}]\\ \\lambda \\lambda 4959,5007+H\\beta }=670^{+260}_{-170} Å contributing 0.56^{+0.16}_{-0.11} mag to the [4.5] filter at z ~ 8. The corresponding {W}_{H\\alpha }=430^{+160}_{-110} Å implies an average specific star formation rate of sSFR=11_{-5}^{+11} Gyr-1 and a stellar population age of 100_{-50}^{+100} Myr. Correcting the spectral energy distribution for the contribution of emission lines lowers the average best-fit stellar masses and mass-to-light ratios by ~3 ×, decreasing the integrated stellar mass density to \\rho ^*(z=8,M_{\\rm{UV}}Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs #11563, 9797. Based on observations with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of
The Team Climate Inventory: application in hospital teams and methodological considerations.
Ouwens, M; Hulscher, M; Akkermans, R; Hermens, R; Grol, R; Wollersheim, H
2008-08-01
To test the validity, reliability and discriminating capacity of an instrument to assess team climate, the Team Climate Inventory (TCI), in a sample of Dutch hospital teams. The TCI is based on a four-factor theory of team climate for innovation. Validation study. Hospital teams in The Netherlands. 424 healthcare professionals; 355 nurses working in 22 nursing teams and 69 nurses and doctors working in 14 quality-improvement teams. Exploratory and confirmatory factor analyses, Pearson's product moment correlations, internal homogeneity of the TCI scales based on Cronbach alpha, and the TCI capability to discriminate between two types of healthcare teams, namely nursing teams and quality-improvement teams. The validity test revealed the TCI's five-factor structure and moderate data fit. The Cronbach alphas of the five scales showed acceptable reliabilities. The TCI discriminated between nursing teams and quality-improvement teams. The mean scores of quality-improvement teams were all significantly higher than those of the nursing teams. Patient care teams are essential for high-quality patient care, and team climate is an important characteristic of successful teams. This study shows that the TCI is a valid, reliable and discriminating self-report measure of team climate in hospital teams. The TCI can be used as a quality-improvement tool or in quality-of-care research.
Team Psychological Safety and Team Learning: A Cultural Perspective
Cauwelier, Peter; Ribière, Vincent M.; Bennet, Alex
2016-01-01
Purpose: The purpose of this paper was to evaluate if the concept of team psychological safety, a key driver of team learning and originally studied in the West, can be applied in teams from different national cultures. The model originally validated for teams in the West is applied to teams in Thailand to evaluate its validity, and the views team…
THE PANCHROMATIC HUBBLE ANDROMEDA TREASURY
International Nuclear Information System (INIS)
Dalcanton, Julianne J.; Williams, Benjamin F.; Rosenfield, Philip; Weisz, Daniel R.; Gilbert, Karoline M.; Gogarten, Stephanie M.; Lang, Dustin; Lauer, Tod R.; Dong Hui; Kalirai, Jason S.; Boyer, Martha L.; Gordon, Karl D.; Seth, Anil C.; Dolphin, Andrew; Bell, Eric F.; Bianchi, Luciana C.; Caldwell, Nelson; Dorman, Claire E.; Guhathakurta, Puragra; Girardi, Léo
2012-01-01
The Panchromatic Hubble Andromeda Treasury is an ongoing Hubble Space Telescope Multi-Cycle Treasury program to image ∼1/3 of M31's star-forming disk in six filters, spanning from the ultraviolet (UV) to the near-infrared (NIR). We use the Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) to resolve the galaxy into millions of individual stars with projected radii from 0 to 20 kpc. The full survey will cover a contiguous 0.5 deg 2 area in 828 orbits. Imaging is being obtained in the F275W and F336W filters on the WFC3/UVIS camera, F475W and F814W on ACS/WFC, and F110W and F160W on WFC3/IR. The resulting wavelength coverage gives excellent constraints on stellar temperature, bolometric luminosity, and extinction for most spectral types. The data produce photometry with a signal-to-noise ratio of 4 at m F275W = 25.1, m F336W = 24.9, m F475W = 27.9, m F814W = 27.1, m F110W = 25.5, and m F160W = 24.6 for single pointings in the uncrowded outer disk; in the inner disk, however, the optical and NIR data are crowding limited, and the deepest reliable magnitudes are up to 5 mag brighter. Observations are carried out in two orbits per pointing, split between WFC3/UVIS and WFC3/IR cameras in primary mode, with ACS/WFC run in parallel. All pointings are dithered to produce Nyquist-sampled images in F475W, F814W, and F160W. We describe the observing strategy, photometry, astrometry, and data products available for the survey, along with extensive testing of photometric stability, crowding errors, spatially dependent photometric biases, and telescope pointing control. We also report on initial fits to the structure of M31's disk, derived from the density of red giant branch stars, in a way that is independent of assumed mass-to-light ratios and is robust to variations in dust extinction. These fits also show that the 10 kpc ring is not just a region of enhanced recent star formation, but is instead a dynamical structure containing a significant overdensity of
Belbin, R Meredith Meredith
2012-01-01
Meredith Belbin's work on teams has become part of everyday language in organizations all over the world. All kinds of teams and team behaviours are covered. At the end of the book is a self-perception inventory so that readers can match their own personalities to particular team roles. Management Teams is required reading for managers concerned with achieving results by getting the best from their key personnel.
CONSTRAINING DUST AND COLOR VARIATIONS OF HIGH-z SNe USING NICMOS ON THE HUBBLE SPACE TELESCOPE
International Nuclear Information System (INIS)
Nobili, S.; Amanullah, R.; Goobar, A.
2009-01-01
We present data from the Supernova Cosmology Project for five high redshift Type Ia supernovae (SNe Ia) that were obtained using the NICMOS infrared camera on the Hubble Space Telescope. We add two SNe from this sample to a rest-frame I-band Hubble diagram, doubling the number of high redshift supernovae on this diagram. This I-band Hubble diagram is consistent with a flat universe (Ω M , Ω Λ ) = (0.29, 0.71). A homogeneous distribution of large grain dust in the intergalactic medium (replenishing dust) is incompatible with the data and is excluded at the 5σ confidence level, if the SN host galaxy reddening is corrected assuming R V = 1.75. We use both optical and infrared observations to compare photometric properties of distant SNe Ia with those of nearby objects. We find generally good agreement with the expected color evolution for all SNe except the highest redshift SN in our sample (SN 1997ek at z = 0.863) which shows a peculiar color behavior. We also present spectra obtained from ground-based telescopes for type identification and determination of redshift.
Virtual Team Governance: Addressing the Governance Mechanisms and Virtual Team Performance
Zhan, Yihong; Bai, Yu; Liu, Ziheng
As technology has improved and collaborative software has been developed, virtual teams with geographically dispersed members spread across diverse physical locations have become increasingly prominent. Virtual team is supported by advancing communication technologies, which makes virtual teams able to largely transcend time and space. Virtual teams have changed the corporate landscape, which are more complex and dynamic than traditional teams since the members of virtual teams are spread on diverse geographical locations and their roles in the virtual team are different. Therefore, how to realize good governance of virtual team and arrive at good virtual team performance is becoming critical and challenging. Good virtual team governance is essential for a high-performance virtual team. This paper explores the performance and the governance mechanism of virtual team. It establishes a model to explain the relationship between the performance and the governance mechanisms in virtual teams. This paper is focusing on managing virtual teams. It aims to find the strategies to help business organizations to improve the performance of their virtual teams and arrive at the objectives of good virtual team management.
Putting the "Team" in the Fine Arts Team: An Application of Business Management Team Concepts
Fisher, Ryan
2007-01-01
In this article, the author discusses current challenges to the idea of teamwork in fine arts teams, redefines the terms team and collaboration using a business management perspective, discusses the success of effective teams in the business world and the characteristics of those teams, and proposes the implementation of the business model of…
A Project Team: A Team or Just a Group?
Directory of Open Access Journals (Sweden)
Katerina Hrazdilova Bockova
2013-11-01
Full Text Available This paper deals with issues related to work in either teams or groups. The theoretical part which discusses a team and a group with regards to its definition, classification and basic distinction brings in more on the typology of team roles, personality assessment and sociometric methods. The analytical part tests the project (work team of a medical center represented in terms of personality and motivational types, team roles and interpersonal team relations concerning the willingness of cooperation and communication. The main objective of this work was to determine whether the existing team is not by its nature rather a working group that contributes to the generally perceived stagnation of that field.
Hubble Space Telescope via the Web
O'Dea, Christopher P.
The Space Telescope Science Institute (STScI) makes available a wide variety of information concerning the Hubble Space Telescope (HST) via the Space Telescope Electronic Information Service (STEIS). STEIS is accessible via anonymous ftp, gopher, WAIS, and WWW. The information on STEIS includes how to propose for time on the HST, the current status of HST, reports on the scientific instruments, the observing schedule, data reduction software, calibration files, and a set of publicly available images in JPEG, GIF and TIFF format. STEIS serves both the astronomical community as well as the larger Internet community. WWW is currently the most widely used interface to STEIS. Future developments on STEIS are expected to include larger amounts of hypertext, especially HST images and educational material of interest to students, educators, and the general public, and the ability to query proposal status.
Straughn, Amber
2011-01-01
Over the past 20 years the Hubble Space Telescope has revolutionized our understanding of the Universe. Most recently, the complete refurbishment of Hubble in 2009 has given new life to the telescope and the new science instruments have already produced groundbreaking science results, revealing some of the most distant galaxy candidates ever discovered. Despite the remarkable advances in astrophysics that Hubble has provided, the new questions that have arisen demand a new space telescope with new technologies and capabilities. I will present the exciting new technology development and science goals of NASA's James Webb Space Telescope, which is currently being built and tested and will be launched this decade.
Noh, Jae Hang
2013-01-01
Knowledge sharing in work teams is one of the critical team processes. Without sharing of knowledge, work teams and organizations may not be able to fully utilize the diverse knowledge brought into work teams by their members. The purpose of this study was to investigate antecedents and underlying mechanisms influencing the extent to which team…
[Investigation of team processes that enhance team performance in business organization].
Nawata, Kengo; Yamaguchi, Hiroyuki; Hatano, Toru; Aoshima, Mika
2015-02-01
Many researchers have suggested team processes that enhance team performance. However, past team process models were based on crew team, whose all team members perform an indivisible temporary task. These models may be inapplicable business teams, whose individual members perform middle- and long-term tasks assigned to individual members. This study modified the teamwork model of Dickinson and McIntyre (1997) and aimed to demonstrate a whole team process that enhances the performance of business teams. We surveyed five companies (member N = 1,400, team N = 161) and investigated team-level-processes. Results showed that there were two sides of team processes: "communication" and "collaboration to achieve a goal." Team processes in which communication enhanced collaboration improved team performance with regard to all aspects of the quantitative objective index (e.g., current income and number of sales), supervisor rating, and self-rating measurements. On the basis of these results, we discuss the entire process by which teamwork enhances team performance in business organizations.
Individual and team performance in team-handball: a review.
Wagner, Herbert; Finkenzeller, Thomas; Würth, Sabine; von Duvillard, Serge P
2014-12-01
Team handball is a complex sport game that is determined by the individual performance of each player as well as tactical components and interaction of the team. The aim of this review was to specify the elements of team-handball performance based on scientific studies and practical experience, and to convey perspectives for practical implication. Scientific studies were identified via data bases of PubMed, Web of Knowledge, SPORT Discus, Google Scholar, and Hercules. A total of 56 articles met the inclusion criteria. In addition, we supplemented the review with 13 additional articles, proceedings and book sections. It was found that the specific characteristics of team-handball with frequent intensity changes, team-handball techniques, hard body confrontations, mental skills and social factors specify the determinants of coordination, endurance, strength and cognition. Although we found comprehensive studies examining individual performance in team-handball players of different experience level, sex or age, there is a lack of studies, particularly for team-handball specific training, as well as cognition and social factors. Key PointsThe specific characteristics of team-handball with frequent intensity changes, specific skills, hard body confrontations, mental skills and social factors define the determinants of coordination, endurance, strength and cognition.To increase individual and team performance in team-handball specific training based on these determinants have been suggested.Although there are comprehensive studies examining individual performance in team-handball players of different experience level, sex, or age are published, there is a lack of training studies, particularly for team-handball specific techniques and endurance, as well as cognition and social factors.
Metrical connection in space-time, Newton's and Hubble's laws
International Nuclear Information System (INIS)
Maeder, A.
1978-01-01
The theory of gravitation in general relativity is not scale invariant. Here, we follow Dirac's proposition of a scale invariant theory of gravitation (i.e. a theory in which the equations keep their form when a transformation of scale is made). We examine some concepts of Weyl's geometry, like the metrical connection, the scale transformations and invariance, and we discuss their consequences for the equation of the geodetic motion and for its Newtonian limit. Under general conditions, we show that the only non-vanishing component of the coefficient of metrical connection may be identified with Hubble's constant. In this framework, the equivalent to the Newtonian approximation for the equation of motion contains an additional acceleration term Hdr vector /dt, which produces an expansion of gravitational systems. The velocity of this expansion is shown to increase linearly with the distance between interacting objects. The relative importance of this new expansion term to the Newtonian one varies like (2rhosub(c)/rho)sup(1/2), where rhosub(c) is the critical density of the Einsteinde Sitter model and rho is the mean density of the considered gravitational configuration. Thus, this 'generalized expansion' is important essentially for systems of mean density not too much above the critical density. Finally, our main conclusion is that in the integrable Weyl geometry, Hubble's law - like Newton's law - would appear as an intrinsic property of gravitation, being only the most visible manifestation of a general effect characterizing the gravitational interaction. (orig.) [de
Dimas, Isabel Dórdio; Renato Lourenço, Paulo; Rebelo, Teresa
2016-07-01
The purpose of this study was to examine the effects of coaching behaviours provided by peers and by the leader on the emotions experienced by interprofessional health and social care teams and on members' satisfaction with the team, as well as on team performance. Data were obtained from a survey among 344 employees working in 52 interprofessional health and social care teams from nine Portuguese organizations. The results show that leader coaching and peer coaching have a positive effect on the level of team members' satisfaction with the team and on positive emotions, and a negative effect on negative emotions. Furthermore, coaching provided by peers presents a positive effect on team performance as assessed by the leader of the team. Our findings put forward the importance of engaging in coaching behaviours to promote quality of the team experience, as well as the achievement of team performance objectives. Further studies should explore how coaching behaviours impact the patient, whose well-being is the ultimate objective of a team in the health and social care system, namely in terms of the patient's perception of quality care or patient outcomes.
DEFF Research Database (Denmark)
Warhuus, Jan; Günzel-Jensen, Franziska; Robinson, Sarah
2016-01-01
types of team formation: random teacher pre-assigned, student selection, and teacher directed diversity. In each of these modules, ethnographic methods (interviews and observations) were employed. Additionally, we had access to students learning logs, formative and summative assessments, and final exams...... functioning entrepreneurial student teams as most teams lack personal chemistry which makes them anchor their work too much in a pre-defined project. In contrast, we find that students that can form their own teams aim for less diverse teams than what is achieved by random assignment. However, the homophily......Questions we care about (Objectives): When students have to work on challenging tasks, as it is often the case in entrepreneurship classrooms that leverage experiential learning, team success becomes central to the students learning. Yet, the formation of teams is often left up to the students...
Cheap Talk: “Team Factors and Management Practices Influence on Team Trust”
Doris Padmini Selvaratnam; Aini Aman; Muhamad Maziz Mahyuddin Bin Kamaludin; Gary Lynn; Richard Reilly
2016-01-01
Team trust has been cited as a contributing factor towards team performance. This paper looks at the antecedents of team trust and to what extent they influence team trust. The antecedents of team trust are team factors like team autonomy, team stability and team member experience; and the management practices are top management involvement and management support. The results demonstrated that team factors and management practices influence team trust individually. The key find...
Hubble Space Telescope: The Telescope, the Observations & the Servicing Mission
1999-11-01
Today the HST Archives contain more than 260 000 astronomical observations. More than 13 000 astronomical objects have been observed by hundreds of different groups of scientists. Direct proof of the scientific significance of this project is the record-breaking number of papers published : over 2400 to date. Some of HST's most memorable achievements are: * the discovery of myriads of very faint galaxies in the early Universe, * unprecedented, accurate measurements of distances to the farthest galaxies, * significant improvement in the determination of the Hubble constant and thus the age of the Universe, * confirmation of the existence of blacks holes, * a far better understanding of the birth, life and death of stars, * a very detailed look at the secrets of the process by which planets are created. Europe and HST ESA's contribution to HST represents a nominal investment of 15%. ESA provided one of the two imaging instruments - the Faint Object Camera (FOC) - and the solar panels. It also has 15 scientists and computer staff working at the Space Telescope Science Institute in Baltimore (Maryland). In Europe the astronomical community receives observational assistance from the Space Telescope European Coordinating Facility (ST-ECF) located in Garching, Munich. In return for ESA's investment, European astronomers have access to approximately 15% of the observing time. In reality the actual observing time competitively allocated to European astronomers is closer to 20%. Looking back at almost ten years of operation, the head of ST-ECF, European HST Project Scientist Piero Benvenuti states: "Hubble has been of paramount importance to European astronomy, much more than the mere 20% of observing time. It has given the opportunity for European scientists to use a top class instrument that Europe alone would not be able to build and operate. In specific areas of research they have now, mainly due to HST, achieved international leadership." One of the major reasons for
Cohesion in Online Student Teams versus Traditional Teams
Hansen, David E.
2016-01-01
Researchers have found that the electronic methods in use for online team communication today increase communication quality in project-based work situations. Because communication quality is known to influence group cohesion, the present research examined whether online student project teams are more cohesive than traditional teams. We tested…
Frank, Cornelia; Linstromberg, Gian-Luca; Hennig, Linda; Heinen, Thomas; Schack, Thomas
2018-02-01
A team's cognitions of interpersonally coordinated actions are a crucial component for successful team performance. Here, we present an approach to practice team action by way of imagery and examine its impact on team cognitions in long-term memory. We investigated the impact of a 4-week team action imagery intervention on futsal players' mental representations of team-level tactics. Skilled futsal players were assigned to either an imagery training group or a no imagery training control group. Participants in the imagery training group practiced four team-level tactics by imagining team actions in specific game situations for three times a week. Results revealed that the imagery training group's representations were more similar to that of an expert representation after the intervention compared with the control group. This study indicates that team action imagery training can have a significant impact on players' tactical skill representations and thus order formation in long-term memory.
Directory of Open Access Journals (Sweden)
Laszlo A. Marosi
2013-01-01
Full Text Available We present a new redshift (RS versus photon travel time ( test including 171 supernovae RS data points. We extended the Hubble diagram to a range of z = 0,0141–8.1 in the hope that at high RSs, the fitting of the calculated RS/ diagrams to the observed RS data would, as predicted by different cosmological models, set constraints on alternative cosmological models. The Lambda cold dark matter (ΛCDM, the static universe model, and the case for a slowly expanding flat universe (SEU are considered. We show that on the basis of the Hubble diagram test, the static and the slowly expanding models are favored.
An updated Type II supernova Hubble diagram
Gall, E. E. E.; Kotak, R.; Leibundgut, B.; Taubenberger, S.; Hillebrandt, W.; Kromer, M.; Burgett, W. S.; Chambers, K.; Flewelling, H.; Huber, M. E.; Kaiser, N.; Kudritzki, R. P.; Magnier, E. A.; Metcalfe, N.; Smith, K.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.
2018-03-01
We present photometry and spectroscopy of nine Type II-P/L supernovae (SNe) with redshifts in the 0.045 ≲ z ≲ 0.335 range, with a view to re-examining their utility as distance indicators. Specifically, we apply the expanding photosphere method (EPM) and the standardized candle method (SCM) to each target, and find that both methods yield distances that are in reasonable agreement with each other. The current record-holder for the highest-redshift spectroscopically confirmed supernova (SN) II-P is PS1-13bni (z = 0.335-0.012+0.009), and illustrates the promise of Type II SNe as cosmological tools. We updated existing EPM and SCM Hubble diagrams by adding our sample to those previously published. Within the context of Type II SN distance measuring techniques, we investigated two related questions. First, we explored the possibility of utilising spectral lines other than the traditionally used Fe IIλ5169 to infer the photospheric velocity of SN ejecta. Using local well-observed objects, we derive an epoch-dependent relation between the strong Balmer line and Fe IIλ5169 velocities that is applicable 30 to 40 days post-explosion. Motivated in part by the continuum of key observables such as rise time and decline rates exhibited from II-P to II-L SNe, we assessed the possibility of using Hubble-flow Type II-L SNe as distance indicators. These yield similar distances as the Type II-P SNe. Although these initial results are encouraging, a significantly larger sample of SNe II-L would be required to draw definitive conclusions. Tables A.1, A.3, A.5, A.7, A.9, A.11, A.13, A.15 and A.17 are also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A25
The Great Attractor: At the Limits of Hubble's Law of the Expanding Universe.
Murdin, Paul
1991-01-01
Presents the origin and mathematics of Hubble's Law of the expanding universe. Discusses limitations to this law and the related concepts of standard candles, elliptical galaxies, and streaming motions, which are conspicuous deviations from the law. The third of three models proposed as explanations for streaming motions is designated: The Great…
Goparaju Purna SUDHAKAR
2013-01-01
Popularity of teams is growing in 21st Century. Organizations are getting their work done through different types of teams. Teams have proved that the collective performance is more than the sum of the individual performances. Thus, the teams have got different dimensions such as quantitative dimensions and qualitative dimensions. The Quantitative dimensions of teams such as team performance, team productivity, team innovation, team effectiveness, team efficiency, team decision making and tea...
Beautiful Teams Inspiring and Cautionary Tales from Veteran Team Leaders
Stellman, Andrew
2009-01-01
What's it like to work on a great software development team facing an impossible problem? How do you build an effective team? Beautiful Teams takes you behind the scenes with some of the most interesting teams in software engineering history. You'll learn from veteran team leaders' successes and failures, told through a series of engaging personal stories -- and interviews -- by leading programmers, architects, project managers, and thought leaders.
Team Building e a enfermagem Team Building e enfermería Team Building and nursing
Directory of Open Access Journals (Sweden)
Filipa Homem
2012-07-01
Full Text Available Num ambiente de insatisfação crescente e de imprevisibilidade como é o da enfermagem, cada vez mais é fundamental motivar as equipas, conferindo-lhes competências pessoais, relacionais, comunicacionais e, acima de tudo, fomentar o trabalho em equipa e consequentemente a produtividade. O Team Building, surge assim como uma estratégia eficaz para obter resultados positivos. Por ser uma estratégia ainda pouco utilizada em Portugal, decidimos realizar este artigo teórico sobre o assunto e refletir sobre a sua pertinência e potencialidades nas equipas de enfermagem, tendo definido como objetivos: aprofundar conhecimentos sobre Team Building, contextualizar o Team Building no âmbito das teorias organizacionais, descrever diferentes modelos de Team Building e refletir sobre a utilidade do Team Building na qualidade da prestação de cuidados de enfermagem. Deste modo, foram pesquisados artigos na plataforma eletrónica de bases de dados EBSCO, assim como consultada literatura relacionada com a psicologia organizacional. Com a presente pesquisa conclui-se que esta estratégia de dinamização de equipas é útil no âmbito da enfermagem, podendo melhorar a comunicação e relações interpessoais, identificar pontos fortes e fracos das equipas, proporcionar maior satisfação no trabalho e, deste modo, aumentar a qualidade dos cuidados de saúde prestados.En un ambiente de creciente descontento y de imprevisibilidad como el de la enfermería, es cada vez más primordial motivar a los equipos, dándoles competencias personales, relacionales, y, sobre todo, fomentar el trabajo en equipo y consecuentemente la productividad. El Team Building surge así como una estrategia eficaz para lograr resultados positivos. Al ser una estrategia aún poco utilizada en Portugal, se decidió realizar este artículo teórico sobre el asunto y reflexionar sobre la pertinencia y el potencial de los equipos de enfermería, para lo que se definieron los objetivos
Bolejko, Krzysztof
2018-01-01
During my talk I will present results suggesting that the phenomenon of emerging spatial curvature could resolve the conflict between Planck's (high-redshift) and Riess et al. (low-redshift) measurements of the Hubble constant. The phenomenon of emerging spatial curvature is absent in the Standard Cosmological Model, which has a flat and fixed spatial curvature (small perturbations are considered in the Standard Cosmological Model but their global average vanishes, leading to spatial flatness at all times).In my talk I will show that with the nonlinear growth of cosmic structures the global average deviates from zero. As a result, the spatial curvature evolves from spatial flatness of the early universe to a negatively curved universe at the present day, with Omega_K ~ 0.1. Consequently, the present day expansion rate, as measured by the Hubble constant, is a few percent higher compared to the high-redshift constraints. This provides an explanation why there is a tension between high-redshift (Planck) and low-redshift (Riess et al.) measurements of the Hubble constant. In the presence of emerging spatial curvature these two measurements should in fact be different: high redshift measurements should be slightly lower than the Hubble constant inferred from the low-redshift data.The presentation will be based on the results described in arXiv:1707.01800 and arXiv:1708.09143 (which discuss the phenomenon of emerging spatial curvature) and on a paper that is still work in progress but is expected to be posted on arxiv by the AAS meeting (this paper uses mock low-redshift data to show that starting from the Planck's cosmological models (in the early universe) but with the emerging spatial curvature taken into account, the low-redshift Hubble constant should be 72.4 km/s/Mpc.
Beaton, Rachael L.; Freedman, Wendy L.; Madore, Barry F.; Bono, Giuseppe; Carlson, Erika K.; Clementini, Gisella; Durbin, Meredith J.; Garofalo, Alessia; Hatt, Dylan; Jang, In Sung; Kollmeier, Juna A.; Lee, Myung Gyoon; Monson, Andrew J.; Rich, Jeffrey A.; Scowcroft, Victoria; Seibert, Mark; Sturch, Laura; Yang, Soung-Chul
2016-12-01
We present an overview of the Carnegie-Chicago Hubble Program, an ongoing program to obtain a 3% measurement of the Hubble constant (H 0) using alternative methods to the traditional Cepheid distance scale. We aim to establish a completely independent route to H 0 using RR Lyrae variables, the tip of the red giant branch (TRGB), and Type Ia supernovae (SNe Ia). This alternative distance ladder can be applied to galaxies of any Hubble type, of any inclination, and, using old stars in low-density environments, is robust to the degenerate effects of metallicity and interstellar extinction. Given the relatively small number of SNe Ia host galaxies with independently measured distances, these properties provide a great systematic advantage in the measurement of H 0 via the distance ladder. Initially, the accuracy of our value of H 0 will be set by the five Galactic RR Lyrae calibrators with Hubble Space Telescope Fine-Guidance Sensor parallaxes. With Gaia, both the RR Lyrae zero-point and TRGB method will be independently calibrated, the former with at least an order of magnitude more calibrators and the latter directly through parallax measurement of tip red giants. As the first end-to-end “distance ladder” completely independent of both Cepheid variables and the Large Magellanic Cloud, this path to H 0 will allow for the high-precision comparison at each rung of the traditional distance ladder that is necessary to understand tensions between this and other routes to H 0. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs #13472 and #13691.
Bilstad, Julie Brat
2016-01-01
This study is a response to the research and request presented by Bang and Midelfart (2010), to further investigate the effect dialogue can have on management team s effectiveness. The purpose of the study was to investigate and explain the effect of team psychological safety on task performance and team member satisfaction, with dialogue as a mediator in this relationship. 215 Norwegian and Danish management teams in the private and public sector were studied. As expected, team psychological...
Selections from 2017: Hubble Survey Explores Distant Galaxies
Kohler, Susanna
2017-12-01
Editors note:In these last two weeks of 2017, well be looking at a few selections that we havent yet discussed on AAS Nova from among the most-downloaded paperspublished in AAS journals this year. The usual posting schedule will resume in January.CANDELS Multi-Wavelength Catalogs: Source Identification and Photometry in the CANDELS COSMOSSurvey FieldPublished January2017Main takeaway:A publication led byHooshang Nayyeri(UC Irvine and UC Riverside) early this year details acatalog of sources built using the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey(CANDELS), a survey carried out by cameras on board the Hubble Space Telescope. The catalogliststhe properties of 38,000 distant galaxies visiblewithin the COSMOS field, a two-square-degree equatorial field explored in depthto answer cosmological questions.Why its interesting:Illustration showing the three-dimensional map of the dark matter distribution in theCOSMOS field. [Adapted from NASA/ESA/R. Massey(California Institute of Technology)]The depth and resolution of the CANDELS observations areuseful for addressingseveral major science goals, including the following:Studying the most distant objects in the universe at the epoch of reionization in the cosmic dawn.Understanding galaxy formation and evolution during the peak epoch of star formation in the cosmic high noon.Studying star formation from deep ultravioletobservations and studying cosmology from supernova observations.Why CANDELS is a major endeavor:CANDELS isthe largest multi-cycle treasury program ever approved on the Hubble Space Telescope using over 900 orbits between 2010 and 2013 withtwo cameras on board the spacecraftto study galaxy formation and evolution throughout cosmic time. The CANDELS images are all publicly available, and the new catalogrepresents an enormous source of information about distant objectsin our universe.CitationH. Nayyeri et al 2017 ApJS 228 7. doi:10.3847/1538-4365/228/1/7
Kirkman, Bradley L; Shapiro, Debra L; Lu, Shuye; McGurrin, Daniel P
2016-04-01
We first review research on culture effects in teams, illustrating that mean levels of team cultural values have main (i.e. direct) effects, indirect effects (i.e. mediated by intervening variables), and moderating influences on team processes and outcomes. Variance in team cultural values or on country of origin (i.e. nationality diversity) also has main effects on team functioning, and we highlight contextual variables that strengthen or weaken these main effects. We next review research examining the effect of variance in team cultural values on global virtual teams, specifically. Finally, we review research on how cultural values shape employees' receptivity to empowering leadership behavior in teams. We conclude by discussing critical areas for future research. Published by Elsevier Ltd.
The innovative rehabilitation team: an experiment in team building.
Halstead, L S; Rintala, D H; Kanellos, M; Griffin, B; Higgins, L; Rheinecker, S; Whiteside, W; Healy, J E
1986-06-01
This article describes an effort by one rehabilitation team to create innovative approaches to team care in a medical rehabilitation hospital. The major arena for implementing change was the weekly patient rounds. We worked to increase patient involvement, developed a rounds coordinator role, used a structured format, and tried to integrate research findings into team decision making. Other innovations included use of a preadmission questionnaire, a discharge check list, and a rounds evaluation questionnaire. The impact of these changes was evaluated using the Group Environment Scale and by analyzing participation in rounds based on verbatim transcripts obtained prior to and 20 months after formation of the Innovative Rehabilitation Team (IRT). The results showed decreased participation by medical personnel during rounds, and increased participation by patients. The rounds coordinator role increased participation rates of staff from all disciplines and the group environment improved within the IRT. These data are compared with similar evaluations made of two other groups, which served as control teams. The problems inherent in making effective, lasting changes in interdisciplinary rehabilitation teams are reviewed, and a plea is made for other teams to explore additional ways to use the collective creativity and resources latent in the team membership.
Walter, Frank; van der Vegt, Gerben S.
2013-01-01
This study examines the role of individual team members' positive mood and perceived team feedback for their team-directed learning behaviour. Results obtained in a sample of 186 members from 27 work teams showed that positive mood was positively associated with team-directed learning behaviour if
The Hubble Constant from SN Refsdal
Vega-Ferrero, J.; Diego, J. M.; Miranda, V.; Bernstein, G. M.
2018-02-01
Hubble Space Telescope observations from 2015 December 11 detected the expected fifth counter-image of supernova (SN) Refsdal at z = 1.49. In this Letter, we compare the time-delay predictions from numerous models with the measured value derived by Kelly et al. from very early data in the light curve of the SN Refsdal and find a best value for {H}0={64}-11+9 {km} {{{s}}}-1 {{Mpc}}-1 (68% CL), in excellent agreement with predictions from cosmic microwave background and recent weak lensing data + baryon acoustic oscillations + Big Bang nucleosynthesis (from the DES Collaboration). This is the first constraint on H 0 derived from time delays between multiple-lensed SN images, and the first with a galaxy cluster lens, subject to systematic effects different from other time-delay H 0 estimates. Additional time-delay measurements from new multiply imaged SNe will allow derivation of competitive constraints on H 0.
Hubble diagram as a probe of minicharged particles
International Nuclear Information System (INIS)
Ahlers, Markus
2009-01-01
The luminosity-redshift relation of cosmological standard candles provides information about the relative energy composition of our Universe. In particular, the observation of type Ia supernovae up to a redshift of z∼2 indicates a universe which is dominated today by dark matter and dark energy. The propagation distance of light from these sources is of the order of the Hubble radius and serves as a very sensitive probe of feeble inelastic photon interactions with background matter, radiation, or magnetic fields. In this paper we discuss the limits on minicharged particle models arising from a dimming effect in supernova surveys. We briefly speculate about a strong dimming effect as an alternative to dark energy.
FMEA team performance in health care: A qualitative analysis of team member perceptions.
Wetterneck, Tosha B; Hundt, Ann Schoofs; Carayon, Pascale
2009-06-01
: Failure mode and effects analysis (FMEA) is a commonly used prospective risk assessment approach in health care. Failure mode and effects analyses are time consuming and resource intensive, and team performance is crucial for FMEA success. We evaluate FMEA team members' perceptions of FMEA team performance to provide recommendations to improve the FMEA process in health care organizations. : Structured interviews and survey questionnaires were administered to team members of 2 FMEA teams at a Midwest Hospital to evaluate team member perceptions of FMEA team performance and factors influencing team performance. Interview transcripts underwent content analysis, and descriptive statistics were performed on questionnaire results to identify and quantify FMEA team performance. Theme-based nodes were categorized using the input-process-outcome model for team performance. : Twenty-eight interviews and questionnaires were completed by 24 team members. Four persons participated on both teams. There were significant differences between the 2 teams regarding perceptions of team functioning and overall team effectiveness that are explained by difference in team inputs and process (e.g., leadership/facilitation, team objectives, attendance of process owners). : Evaluation of team members' perceptions of team functioning produced useful insights that can be used to model future team functioning. Guidelines for FMEA team success are provided.
Team Leadership: Leadership Role Achievement in Supervision Teams in Turkey
Ali Sabanci; Izzet Ozdemir
2015-01-01
The purpose of this paper is to explore the views of team leaders and team members of supervision teams about the extent that team leaders achieve their team leadership roles in Turkey. This research was conducted as a survey. The population of the study consisted of approximately 2650 supervisors (inspectors) working in 81 provinces distributed to seven geographical regions in Turkey. The sample consisted of 563 supervisors which were selected out by random sampling. The data were gathered b...
Hu, Jia; Judge, Timothy A
2017-06-01
Integrating the leader trait perspective with dominance complementarity theory, we propose team power distance as an important boundary condition for the indirect impact of leader extraversion, agreeableness, and conscientiousness on team performance through a team's potency beliefs and through relational identification with the leader. Using time-lagged, 3-source data from 71 teams, we found that leader extraversion had a positive indirect impact on team in-role and extrarole performance through relational identification, but only for high power distance teams; leader conscientiousness had a positive influence on team in-role performance through team potency, but only for high power distance teams; and leader agreeableness had a positive effect on team in-role and extrarole performance via relational identification and on team in-role performance via team potency, but only for low power distance teams. The findings address prior inconsistencies regarding the relationships between leader traits and team effectiveness, identify an important boundary condition and key team processes that bridge the links, and provide a deeper understanding of the role of leader traits in teams. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
The relationship between servant leadership, affective team commitment and team effectiveness
Directory of Open Access Journals (Sweden)
Bright Mahembe
2013-04-01
Full Text Available Orientation: Value-based leadership practices play a critical role in teamwork in high-performance organisations.Research purpose: The aim of the study was to empirically validate a theoretical model explicating the structural relationships between servant leadership, affective team commitment and team effectiveness.Motivation for the study: The increased eliance on teams for production calls for an analysis of the role of follower-focused leadership practices in enhancing eam effectiveness.Research design, approach and method: A non-probabilityand multicultural sample consisting of 202 primary and secondary school teachers was drawn from 32 chools in the Western Cape Province of South Africa.Main findings: High levels of reliability were found and uni-dimensionality of the subscales was demonstrated through exploratory factor analyses. Good fit with the data was found for the measurement models through confirmatory factor analyses. Structural equation modelling showed a reasonable fit for the structural model. Positive relationships were found amongst servant leadership, team effectiveness and affective team commitment. Standard multiple regression analysis showed that affective team commitment moderated the relationship between servant leadership and team effectiveness.Practical/managerial implications: The findings emphasise the central role played by servant leadership and affective team commitment in team performance. Servant leadership fosters team effectiveness if employees feel committed to their work team.Contribution/value-add: The servant leadership style alone may not be a sufficient condition for team effectiveness; other variables, such as affective team commitment, also play a role. The study suggested specific variables that may also combine with leadership to positively influence team effectiveness.
The team halo effect: why teams are not blamed for their failures.
Naquin, Charles E; Tynan, Renee O
2003-04-01
In this study, the existence of the team halo effect, the phenomenon that teams tend not to be blamed for their failures, is documented. With 2 studies using both real teams and controlled scenarios, the authors found evidence that the nature of the causal attribution processes used to diagnose failure scenarios leads to individuals being more likely to be identified as the cause of team failure than the team as a collective. Team schema development, as indexed by team experience, influences this effect, with individuals who have more team experience being less likely to show the team halo effect
DEFF Research Database (Denmark)
Bjørn, Pernille
2005-01-01
Investigating virtual team collaboration in industry using grounded theory this paper presents the in-dept analysis of empirical work conducted in a global organization of 100.000 employees where a global virtual team with participants from Sweden, United Kingdom, Canada, and North America were...... studied. The research question investigated is how collaboration is negotiated within virtual teams? This paper presents findings concerning how collaboration is negotiated within a virtual team and elaborate the difficulties due to invisible articulation work and managing multiple communities...... in transforming the virtual team into a community. It is argued that translucence in communication structures within the virtual team and between team and management is essential for engaging in a positive transformation process of trustworthiness supporting the team becoming a community, managing the immanent...
Team Orientations, Interpersonal Relations, and Team Success
Nixon, Howard L.
1976-01-01
Contradictions in post research on the concepts of "cohesiveness" and team success seem to arise from the ways in which cohesiveness is measured and the nature of the teams investigated in each study. (MB)
Hubble 3D: A Science and Hollywood Collaboration Made (Nearly) in Heaven
Showstack, Randy
2010-04-01
Just 2 days after the 2010 Academy Awards® ceremony in early March bestowed Oscars® for motion picture achievements, NASA deputy administrator Lori Garver touted a new film about the Hubble Space Telescope, Hubble 3D, for best drama, special effects, screenplay, actors and actress, and director and producer. The 43-minute IMAX and Warner Brothers Pictures production, which opened in theaters on 19 March, is an example of the ability of Hollywood and the science community to partner in providing a dynamic educational and entertaining product, according to a number of people associated with the film. Sharing the red carpet at the Smithsonian National Air and Space Museum in Washington, D. C., with astronauts and others to mark the world premiere, Garver said the film shows the drama of the astronauts’ efforts to repair the telescope while traveling 17,000 miles per hour and performing grueling space walks (see Figure 1). “We have literally opened our eyes on the universe through this telescope,” she said. “This is a taxpayer-funded agency, and we are giving back to the public the very story that they paid for.”
Directory of Open Access Journals (Sweden)
Weiqiang Yang
2017-07-01
Full Text Available The coupling between dark energy and dark matter provides a possible approach to mitigate the coincidence problem of the cosmological standard model. In this paper, we assumed the interacting term was related to the Hubble parameter, energy density of dark energy, and equation of state of dark energy. The interaction rate between dark energy and dark matter was a constant parameter, which was, Q = 3 H ξ ( 1 + w x ρ x . Based on the Markov chain Monte Carlo method, we made a global fitting on the interacting dark energy model from Planck 2015 cosmic microwave background anisotropy and observational Hubble data. We found that the observational data sets slightly favored a small interaction rate between dark energy and dark matter; however, there was not obvious evidence of interaction at the 1 σ level.
Bringing the Science of Team Training to School-Based Teams
Benishek, Lauren E.; Gregory, Megan E.; Hodges, Karin; Newell, Markeda; Hughes, Ashley M.; Marlow, Shannon; Lacerenza, Christina; Rosenfield, Sylvia; Salas, Eduardo
2016-01-01
Teams are ubiquitous in schools in the 21st Century; yet training for effective teaming within these settings has lagged behind. The authors of this article developed 5 modules, grounded in the science of team training and adapted from an evidence-based curriculum used in medical settings called TeamSTEPPS®, to prepare instructional and…
The relationship between servant leadership, affective team commitment and team effectiveness
Directory of Open Access Journals (Sweden)
Bright Mahembe
2013-04-01
Full Text Available Orientation: Value-based leadership practices play a critical role in teamwork in high-performance organisations. Research purpose: The aim of the study was to empirically validate a theoretical model explicating the structural relationships between servant leadership, affective team commitment and team effectiveness. Motivation for the study: The increased eliance on teams for production calls for an analysis of the role of follower-focused leadership practices in enhancing eam effectiveness. Research design, approach and method: A non-probabilityand multicultural sample consisting of 202 primary and secondary school teachers was drawn from 32 chools in the Western Cape Province of South Africa. Main findings: High levels of reliability were found and uni-dimensionality of the subscales was demonstrated through exploratory factor analyses. Good fit with the data was found for the measurement models through confirmatory factor analyses. Structural equation modelling showed a reasonable fit for the structural model. Positive relationships were found amongst servant leadership, team effectiveness and affective team commitment. Standard multiple regression analysis showed that affective team commitment moderated the relationship between servant leadership and team effectiveness. Practical/managerial implications: The findings emphasise the central role played by servant leadership and affective team commitment in team performance. Servant leadership fosters team effectiveness if employees feel committed to their work team. Contribution/value-add: The servant leadership style alone may not be a sufficient condition for team effectiveness; other variables, such as affective team commitment, also play a role. The study suggested specific variables that may also combine with leadership to positively influence team effectiveness.
Practice effects on intra-team synergies in football teams.
Silva, Pedro; Chung, Dante; Carvalho, Thiago; Cardoso, Tiago; Davids, Keith; Araújo, Duarte; Garganta, Júlio
2016-04-01
Developing synchronised player movements for fluent competitive match play is a common goal for coaches of team games. An ecological dynamics approach advocates that intra-team synchronization is governed by locally created information, which specifies shared affordances responsible for synergy formation. To verify this claim we evaluated coordination tendencies in two newly-formed teams of recreational players during association football practice games, weekly, for fifteen weeks (thirteen matches). We investigated practice effects on two central features of synergies in sports teams - dimensional compression and reciprocal compensation here captured through near in-phase modes of coordination and time delays between coupled players during forward and backwards movements on field while attacking and defending. Results verified that synergies were formed and dissolved rapidly as a result of the dynamic creation of informational properties, perceived as shared affordances among performers. Practising once a week led to small improvements in the readjustment delays between co-positioning team members, enabling faster regulation of coordinated team actions. Mean values of the number of player and team synergies displayed only limited improvements, possibly due to the timescales of practice. No relationship between improvements in dimensional compression and reciprocal compensation were found for number of shots, amount of ball possession and number of ball recoveries made. Findings open up new perspectives for monitoring team coordination processes in sport. Copyright © 2015 Elsevier B.V. All rights reserved.
It's a team game: exploring factors that influence team experience
Martin, Eleanor
2015-01-01
Many multiplayer games feature teams, and whether they are pitted against each other or against the game itself it seems likely that the way these teams bond will affect the players' experience. What are the factors that influence the experience of being a team member in a game? To what extent can the game designer manipulate the cohesion of the teams by changing the game design? How does the satisfaction of the player with their team relate to their feeling of cohesion? How does cohesion dif...
Collective autonomy and absenteeism within work teams: a team motivation approach.
Rousseau, Vincent; Aubé, Caroline
2013-01-01
This study investigates the role of collective autonomy in regard to team absenteeism by considering team potency as a motivational mediator and task routineness as a moderator. The sample consists of 90 work teams (327 members and 90 immediate superiors) drawn from a public safety organization. Results of structural equation modeling indicate that the relationships between collective autonomy and two indicators of team absenteeism (i.e., absence frequency and time lost) are mediated by team potency. Specifically, collective autonomy is positively related to team potency which in turn is negatively related to team absenteeism. Furthermore, results of hierarchical regression analyses show that task routineness moderates the relationships between collective autonomy and the two indicators of team absenteeism such that these relationships are stronger when the level of task routineness is low. On the whole, this study points out that collective autonomy may exercise a motivational effect on attendance at work within teams, but this effect is contingent on task routineness.
Chiu, Chia-Yen Chad; Owens, Bradley P; Tesluk, Paul E
2016-12-01
The present study was designed to produce novel theoretical insight regarding how leader humility and team member characteristics foster the conditions that promote shared leadership and when shared leadership relates to team effectiveness. Drawing on social information processing theory and adaptive leadership theory, we propose that leader humility facilitates shared leadership by promoting leadership-claiming and leadership-granting interactions among team members. We also apply dominance complementary theory to propose that team proactive personality strengthens the impact of leader humility on shared leadership. Finally, we predict that shared leadership will be most strongly related to team performance when team members have high levels of task-related competence. Using a sample composed of 62 Taiwanese professional work teams, we find support for our proposed hypothesized model. The theoretical and practical implications of these results for team leadership, humility, team composition, and shared leadership are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
1993-02-01
On Wednesday 10 March 1993 astronauts from ESA and NASA will be at British Aerospace Space Systems Limited, Filton, Bristol, UK, training on the replacement set of solar arrays which they are scheduled to fit to the Hubble Space Telescope at year end. You are invited to attend a technical briefing on that day, which will be given by senior representatives of the European Space Agency and British Aerospace. The briefing will include details of the design modifications and status of the solar arrays, together with a brief overview of the scientific results already achieved by the teams of astronomers using the telescope. There will be an opportunity for interviews with the mission specialists in the crew of NASA's Space Shuttle flight STS-61, who will be carrying out the servicing mission for the Hubble Space Telescope in a series of "Extra-Vehicular Activities - EVA' (space-walks). Five astronauts are expected : Story Musgrave, Colonel Tom Akers, Jeffrey A. Hoffman, Kathryn C. Thornton from NASA and Claude Nicollier from ESA. There will also be a chance to view the solar arrays in the British Aerospace clean room area where the astronauts are working on their familiarisation programme. The briefing will take place on Wednesday 10 March 1993 at British Aerospace Space Systems, Filton, Bristol, UK (on the northern outskirts of the city of Bristol). The event will begin at 10h30 a.m. and end with a buffet lunch running from approximately 01h30 p.m. to 02h30 p.m. In order to assists with arrangements for travel to and from bristol, British Aerospace proposes to run a free coach from and to London Victoria Coach Station - if there proves to be sufficient press interest. This coach would depart from London at approximately 07h50 a.m. and arrive back at around 05h30 p.m. Further details will be available on request when numbers are known. In order to gain access to the site and the briefing it is essential that all attendees are expected and their names are provided in
Discovery of Hubble's Law as a Series of Type III Errors
Belenkiy, Ari
2015-01-01
Recently much attention has been paid to the history of the discovery of Hubble's law--the linear relation between the rate of recession of the remote galaxies and distance to them from Earth. Though historians of cosmology now mention several names associated with this law instead of just one, the motivation of each actor of that remarkable…
Hoe teams deadlines halen : een aanzet tot team-timemanagement
Gevers, J.M.P.; Rutte, C.G.
2014-01-01
Dit artikel geeft een overzicht van de stand van zaken in de wetenschappelijk literatuur ten aanzien van de vraag hoe teams hun deadlines halen. Het beschikbare materiaal wijst erop dat teams beter in staat zijn om deadlines te halen als teamleden, naast een gemeenschappelijke visie op het team en
DEFF Research Database (Denmark)
Warhuus, Jan; Günzel-Jensen, Franziska; Robinson, Sarah
or pre-arranged at random. Therefore we investigate the importance of team formation in the entrepreneurial classroom and ask: (i) What are the underlying factors that influence outcomes of teamwork in student groups? (ii) How does team formation influence student perception of learning?, and (iii) Do...... different team formation strategies produce different teamwork and learning outcomes? Approach: We employed a multiple case study design comprising of 38 student teams to uncover potential links between team formation and student perception of learning. This research draws on data from three different....... A rigorous coding and inductive analysis process was undertaken. Pattern and relationship coding were used to reveal underlying factors, which helped to unveil important similarities and differences between student in different teams’ project progress and perception of learning. Results: When students...
The effects of team reflexivity on psychological well-being in manufacturing teams.
Chen, Jingqiu; Bamberger, Peter A; Song, Yifan; Vashdi, Dana R
2018-04-01
While the impact of team reflexivity (a.k.a. after-event-reviews, team debriefs) on team performance has been widely examined, we know little about its implications on other team outcomes such as member well-being. Drawing from prior team reflexivity research, we propose that reflexivity-related team processes reduce demands, and enhance control and support. Given the centrality of these factors to work-based strain, we posit that team reflexivity, by affecting these factors, may have beneficial implications on 3 core dimensions of employee burnout, namely exhaustion, cynicism, and inefficacy (reduced personal accomplishment). Using a sample of 469 unskilled manufacturing workers employed in 73 production teams in a Southern Chinese factory, we implemented a time lagged, quasi-field experiment, with half of the teams trained in and executing an end-of-shift team debriefing, and the other half assigned to a control condition and undergoing periodic postshift team-building exercises. Our findings largely supported our hypotheses, demonstrating that relative to team members assigned to the control condition, those assigned to the reflexivity condition experienced a significant improvement in all 3 burnout dimensions over time. These effects were mediated by control and support (but not demands) and amplified as a function of team longevity. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Posthuma, Richard; Al-Riyami, Said
2012-01-01
Leaders of higher education institutions can create top management teams of academic administrators to guide and improve their organizations. This study illustrates how the leadership of top management teams can be accomplished successfully through a combination of goal setting (Doran, 1981; Locke & Latham, 1990), understanding of team roles…
Extra-team connections for knowledge transfer between staff teams
Ramanadhan, Shoba; Wiecha, Jean L.; Emmons, Karen M.; Gortmaker, Steven L.; Viswanath, Kasisomayajula
2009-01-01
As organizations implement novel health promotion programs across multiple sites, they face great challenges related to knowledge management. Staff social networks may be a useful medium for transferring program-related knowledge in multi-site implementation efforts. To study this potential, we focused on the role of extra-team connections (ties between staff members based in different site teams) as potential channels for knowledge sharing. Data come from a cross-sectional study of afterschool childcare staff implementing a health promotion program at 20 urban sites of the Young Men's Christian Association of Greater Boston. We conducted a sociometric social network analysis and attempted a census of 91 program staff members. We surveyed 80 individuals, and included 73 coordinators and general staff, who lead and support implementation, respectively, in this study. A multiple linear regression model demonstrated a positive relationship between extra-team connections (β = 3.41, P knowledge transfer. We also found that intra-team connections (within-team ties between staff members) were also positively related to skill receipt. Connections between teams appear to support knowledge transfer in this network, but likely require greater active facilitation, perhaps via organizational changes. Further research on extra-team connections and knowledge transfer in low-resource, high turnover environments is needed. PMID:19528313
HUBBLE CAPTURES THE HEART OF STAR BIRTH
2002-01-01
NASA Hubble Space Telescope's Wide Field and Planetary Camera 2 (WFPC2) has captured a flurry of star birth near the heart of the barred spiral galaxy NGC 1808. On the left are two images, one superimposed over the other. The black-and-white picture is a ground-based view of the entire galaxy. The color inset image, taken with the Hubble telescope's Wide Field and Planetary Camera 2 (WFPC2), provides a close-up view of the galaxy's center, the hotbed of vigorous star formation. The ground-based image shows that the galaxy has an unusual, warped shape. Most spiral galaxies are flat disks, but this one has curls of dust and gas at its outer spiral arms (upper right-hand corner and lower left-hand corner). This peculiar shape is evidence that NGC 1808 may have had a close interaction with another nearby galaxy, NGC 1792, which is not in the picture Such an interaction could have hurled gas towards the nucleus of NGC 1808, triggering the exceptionally high rate of star birth seen in the WFPC2 inset image. The WFPC2 inset picture is a composite of images using colored filters that isolate red and infrared light as well as light from glowing hydrogen. The red and infrared light (seen as yellow) highlight older stars, while hydrogen (seen as blue) reveals areas of star birth. Colors were assigned to this false-color image to emphasize the vigorous star formation taking place around the galaxy's center. NGC 1808 is called a barred spiral galaxy because of the straight lines of star formation on both sides of the bright nucleus. This star formation may have been triggered by the rotation of the bar, or by matter which is streaming along the bar towards the central region (and feeding the star burst). Filaments of dust are being ejected from the core into a faint halo of stars surrounding the galaxy's disk (towards the upper left corner) by massive stars that have exploded as supernovae in the star burst region. The portion of the galaxy seen in this 'wide-field' image is
Super-Hubble de Sitter fluctuations and the dynamical RG
Energy Technology Data Exchange (ETDEWEB)
Burgess, C.P. [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario (Canada); Leblond, L.; Shandera, S. [Perimeter Institute for Theoretical Physics, Waterloo, Ontario (Canada); Holman, R., E-mail: cburgess@perimeterinstitute.ca, E-mail: lleblond@perimeterinstitute.ca, E-mail: rha@andrew.cmu.edu, E-mail: sshandera@perimeterinstitute.ca [Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States)
2010-03-01
Perturbative corrections to correlation functions for interacting theories in de Sitter spacetime often grow secularly with time, due to the properties of fluctuations on super-Hubble scales. This growth can lead to a breakdown of perturbation theory at late times. We argue that Dynamical Renormalization Group (DRG) techniques provide a convenient framework for interpreting and resumming these secularly growing terms. In the case of a massless scalar field in de Sitter with quartic self-interaction, the resummed result is also less singular in the infrared, in precisely the manner expected if a dynamical mass is generated. We compare this improved infrared behavior with large-N expansions when applicable.
Electrostatic Studies for the 2008 Hubble Service Repair Mission
Buhler, C. R.; Clements, J. S.; Calle, C. I.
2012-01-01
High vacuum triboelectric testing of space materials was required to identify possible Electrostatic Discharge (ESD) concerns for the astronauts in space during electronics board replacement on the Hubble Space Telescope. Testing under high vacuum conditions with common materials resulted in some interesting results. Many materials were able to charge to high levels which did not dissipate quickly even when grounded. Certain materials were able to charge up in contact with grounded metals while others were not. An interesting result was that like materials did not exchange electrostatic charge under high vacuum conditions. The most surprising experimental result is the lack of brush discharges from charged insulators under high vacuum conditions.
Fleury, Marie-Josée; Grenier, Guy; Bamvita, Jean-Marie
2017-01-01
Objectives: The aim of this study was to determine the respective contribution of professional characteristics, team attributes, team processes, and team emergent states on the job satisfaction of 315 mental health professionals from Quebec (Canada). Methods: Job satisfaction was measured with the Job Satisfaction Survey. Independent variables were organized into four categories according to a conceptual framework inspired from the Input-Mediator-Outcomes-Input Model. The contribution of each category of variables was assessed using hierarchical regression analysis. Results: Variations in job satisfaction were mostly explained by team processes, with minimal contribution from the other three categories. Among the six variables significantly associated with job satisfaction in the final model, four were team processes: stronger team support, less team conflict, deeper involvement in the decision-making process, and more team collaboration. Job satisfaction was also associated with nursing and, marginally, male gender (professional characteristics) as well as with a stronger affective commitment toward the team (team emergent states). Discussion and Conclusion: Results confirm the importance for health managers of offering adequate support to mental health professionals, and creating an environment favorable to collaboration and decision-sharing, and likely to reduce conflicts between team members. PMID:29276591
Fleury, Marie-Josée; Grenier, Guy; Bamvita, Jean-Marie
2017-01-01
The aim of this study was to determine the respective contribution of professional characteristics, team attributes, team processes, and team emergent states on the job satisfaction of 315 mental health professionals from Quebec (Canada). Job satisfaction was measured with the Job Satisfaction Survey. Independent variables were organized into four categories according to a conceptual framework inspired from the Input-Mediator-Outcomes-Input Model. The contribution of each category of variables was assessed using hierarchical regression analysis. Variations in job satisfaction were mostly explained by team processes, with minimal contribution from the other three categories. Among the six variables significantly associated with job satisfaction in the final model, four were team processes: stronger team support, less team conflict, deeper involvement in the decision-making process, and more team collaboration. Job satisfaction was also associated with nursing and, marginally, male gender (professional characteristics) as well as with a stronger affective commitment toward the team (team emergent states). Results confirm the importance for health managers of offering adequate support to mental health professionals, and creating an environment favorable to collaboration and decision-sharing, and likely to reduce conflicts between team members.
The Hubble Frontier Fields: Engaging Multiple Audiences in Exploring the Cosmic Frontier
Lawton, Brandon L.; Smith, Denise A.; Summers, Frank; Ryer, Holly; Slivinski, Carolyn; Lotz, Jennifer M.
2017-06-01
The Hubble Frontier Fields is a multi-cycle program of six deep-field observations of strong-lensing galaxy clusters taken in parallel with six deep “blank fields.” The three-year long collaborative program began in late 2013 and is led by observations from NASA’s Great Observatories. The observations, now complete, allow astronomers to look deeper into the universe than ever before, and potentially uncover galaxies that are as much as 100 times fainter than what the telescopes can typically observe. The Frontier Fields science program is ideal for informing audiences about scientific advances and topics in STEM. The study of galaxy properties, statistics, optics, and Einstein’s theory of general relativity naturally leverages off of the science returns of the Frontier Fields program. As a result, the Space Telescope Science Institute’s Office of Public Outreach (OPO) has engaged multiple audiences over the past three years to follow the progress of the Frontier Fields.For over two decades, the STScI outreach program has sought to bring the wonders of the universe to the public and engage audiences in the adventure of scientific discovery. In addition, we are leveraging the reach of the new NASA’s Universe of Learning education program to bring the science of the Frontier Fields to informal education audiences. The main underpinnings of the STScI outreach program and the Universe of Learning education program are scientist-educator development teams, partnerships, and an embedded program evaluation component. OPO is leveraging the infrastructure of these education and outreach programs to bring the Frontier Fields science program to the education community and the public in a cost-effective way.This talk will feature highlights over the past three years of the program. We will highlight OPO’s strategies and infrastructure that allows for the quick delivery of groundbreaking science to the education community and public.
The Team Climate Inventory: application in hospital teams and methodological considerations.
Ouwens, M.M.T.J.; Hulscher, M.E.J.L.; Akkermans, R.P.; Hermens, R.P.M.G.; Grol, R.P.T.M.; Wollersheim, H.C.H.
2008-01-01
OBJECTIVE: To test the validity, reliability and discriminating capacity of an instrument to assess team climate, the Team Climate Inventory (TCI), in a sample of Dutch hospital teams. The TCI is based on a four-factor theory of team climate for innovation. DESIGN: Validation study. SETTING:
Team Scaffolds: How Minimal Team Structures Enable Role-based Coordination
Valentine, Melissa A
2013-01-01
In this dissertation, I integrate research on role-based coordination with concepts adapted from the team effectiveness literature to theorize how minimal team structures support effective coordination when people do not work together regularly. I argue that role-based coordination among relative strangers can be interpersonally challenging and propose that team scaffolds (minimal team structures that bound groups of roles rather than groups of individuals) may provide occupants with a tempor...
Teams, Team Motivation, and the Theory of the Firm
DEFF Research Database (Denmark)
Foss, Nicolai Juul; Lindenberg, Siegwart
A concern with teams was central to early attempts to grasp the nature of the firm, but fell out of favor in later work. We encourage a return to the emphasis on teams, but argue that the idea of teams as central to the nature of the firm needs to be grounded in an appreciation of the importance...
Brett, Jeanne; Behfar, Kristin; Kern, Mary C
2006-11-01
Multicultural teams offer a number of advantages to international firms, including deep knowledge of different product markets, culturally sensitive customer service, and 24-hour work rotations. But those advantages may be outweighed by problems stemming from cultural differences, which can seriously impair the effectiveness of a team or even bring itto a stalemate. How can managers best cope with culture-based challenges? The authors conducted in-depth interviews with managers and members of multicultural teams from all over the world. Drawing on their extensive research on dispute resolution and teamwork and those interviews, they identify four problem categories that can create barriers to a team's success: direct versus indirect communication, trouble with accents and fluency, differing attitudes toward hierarchy and authority, and conflicting norms for decision making. If a manager--or a team member--can pinpoint the root cause of the problem, he or she is likelier to select an appropriate strategy for solving it. The most successful teams and managers, the authors found, dealt with multicultural challenges in one of four ways: adaptation (acknowledging cultural gaps openly and working around them), structural intervention (changing the shape or makeup of the team), managerial intervention (setting norms early or bringing in a higher-level manager), and exit (removing a team member when other options have failed). Which strategy is best depends on the particular circumstances--and each has potential complications. In general, though, managers who intervene early and set norms; teams and managers who try to engage everyone on the team; and teams that can see challenges as stemming from culture, not personality, succeed in solving culture-based problems with good humor and creativity. They are the likeliest to harvest the benefits inherent in multicultural teams.
The Hubble Legacy Archive ACS grism data
Kümmel, M.; Rosati, P.; Fosbury, R.; Haase, J.; Hook, R. N.; Kuntschner, H.; Lombardi, M.; Micol, A.; Nilsson, K. K.; Stoehr, F.; Walsh, J. R.
2011-06-01
A public release of slitless spectra, obtained with ACS/WFC and the G800L grism, is presented. Spectra were automatically extracted in a uniform way from 153 archival fields (or "associations") distributed across the two Galactic caps, covering all observations to 2008. The ACS G800L grism provides a wavelength range of 0.55-1.00 μm, with a dispersion of 40 Å/pixel and a resolution of ~80 Å for point-like sources. The ACS G800L images and matched direct images were reduced with an automatic pipeline that handles all steps from archive retrieval, alignment and astrometric calibration, direct image combination, catalogue generation, spectral extraction and collection of metadata. The large number of extracted spectra (73,581) demanded automatic methods for quality control and an automated classification algorithm was trained on the visual inspection of several thousand spectra. The final sample of quality controlled spectra includes 47 919 datasets (65% of the total number of extracted spectra) for 32 149 unique objects, with a median iAB-band magnitude of 23.7, reaching 26.5 AB for the faintest objects. Each released dataset contains science-ready 1D and 2D spectra, as well as multi-band image cutouts of corresponding sources and a useful preview page summarising the direct and slitless data, astrometric and photometric parameters. This release is part of the continuing effort to enhance the content of the Hubble Legacy Archive (HLA) with highly processed data products which significantly facilitate the scientific exploitation of the Hubble data. In order to characterize the slitless spectra, emission-line flux and equivalent width sensitivity of the ACS data were compared with public ground-based spectra in the GOODS-South field. An example list of emission line galaxies with two or more identified lines is also included, covering the redshift range 0.2 - 4.6. Almost all redshift determinations outside of the GOODS fields are new. The scope of science projects
Team Effectiveness and Team Development in CSCL
Fransen, Jos; Weinberger, Armin; Kirschner, Paul A.
2013-01-01
There is a wealth of research on computer-supported cooperative work (CSCW) that is neglected in computer-supported collaborative learning (CSCL) research. CSCW research is concerned with contextual factors, however, that may strongly influence collaborative learning processes as well, such as task characteristics, team formation, team members'…
Group, Team, or Something in Between? Conceptualising and Measuring Team Entitativity
Vangrieken, Katrien; Boon, Anne; Dochy, Filip; Kyndt, Eva
2017-01-01
The current gap between traditional team research and research focusing on non-strict teams or groups such as teacher teams hampers boundary-crossing investigations of and theorising on teamwork and collaboration. The main aim of this study includes bridging this gap by proposing a continuum-based team concept, describing the distinction between…
DEFF Research Database (Denmark)
Clausen, Lisbeth
, maintaining team cohesiveness in multicultural teams to collaborate effectively presents a number of challenges. The present study employs the concept of trust to explore influences on team collaboration in high performing teams. The study is based on observation of teams in seven multinational corporations...... and interviews with managers from the US, Europe, China and Japan. The study presents a conceptual framework - a ‘trust buffer’ – which enables analysis and exemplification of the dynamics and challenges of teams as drivers of change. Each team has strategically important tasks, unique capacities and deal...... with change in particular ways: Each team is analyzed in relation to its global (HQ) mandate, local (national) stakeholders and organizational context. It is found that communication energy, resources and team mandate underscore the sense of trust in high performing teams. Diversity is understood...
Gibbard, Katherine; Griep, Yannick; De Cooman, Rein; Hoffart, Genevieve; Onen, Denis; Zareipour, Hamidreza
2017-01-01
With the knowledge that team work is not always associated with high(er) performance, we draw from the Multi-Level Theory of Psychological Contracts, Person-Environment Fit Theory, and Optimal Distinctiveness Theory to study shared perceptions of psychological contract (PC) breach in relation to shared perceptions of complementary and supplementary fit to explain why some teams perform better than other teams. We collected three repeated survey measures in a sample of 128 respondents across 46 teams. After having made sure that we met all statistical criteria, we aggregated our focal variables to the team-level and analyzed our data by means of a longitudinal three-wave autoregressive moderated-mediation model in which each relationship was one-time lag apart. We found that shared perceptions of PC breach were directly negatively related to team output and negatively related to perceived team member effectiveness through a decrease in shared perceptions of supplementary fit. However, we also demonstrated a beneficial process in that shared perceptions of PC breach were positively related to shared perceptions of complementary fit, which in turn were positively related to team output. Moreover, best team output appeared in teams that could combine high shared perceptions of complementary fit with modest to high shared perceptions of supplementary fit. Overall, our findings seem to indicate that in terms of team output there may be a bright side to perceptions of PC breach and that perceived person-team fit may play an important role in this process.
PACMan to Help Sort Hubble Proposals
Kohler, Susanna
2017-04-01
Every year, astronomers submit over a thousand proposals requesting time on the Hubble Space Telescope (HST). Currently, humans must sort through each of these proposals by hand before sending them off for review. Could this burden be shifted to computers?A Problem of VolumeAstronomer Molly Peeples gathered stats on the HST submissions sent in last week for the upcoming HST Cycle 25 (the deadline was Friday night), relative to previous years. This years proposal round broke the record, with over 1200 proposals submitted in total for Cycle 25. [Molly Peeples]Each proposal cycle for HST time attracts on the order of 1100 proposals accounting for far more HST time than is available. The proposals are therefore carefully reviewed by around 150 international members of the astronomy community during a six-month process to select those with the highest scientific merit.Ideally, each proposal will be read by reviewers that have scientific expertise relevant to the proposal topic: if a proposal requests HST time to study star formation, for instance, then the reviewers assigned to it should have research expertise in star formation.How does this matching of proposals to reviewers occur? The current method relies on self-reported categorization of the submitted proposals. This is unreliable, however; proposals are often mis-categorized by submitters due to misunderstanding or ambiguous cases.As a result, the Science Policies Group at the Space Telescope Science Institute (STScI) which oversees the review of HST proposals must go through each of the proposals by hand and re-categorize them. The proposals are then matched to reviewers with self-declared expertise in the same category.With the number of HST proposals on the rise and the expectation that the upcoming James Webb Space Telescope (JWST) will elicit even more proposals for time than Hubble scientists at STScI and NASA are now asking: could the human hours necessary for this task be spared? Could a computer program
UV/Visible Telescope with Hubble Disposal
Benford, Dominic J.
2013-01-01
Submission Overview: Our primary objective is to convey a sense of the significant advances possible in astrophysics investigations for major Cosmic Origins COR program goals with a 2.4m telescope asset outfitted with one or more advanced UV visible instruments. Several compelling science objectives were identified based on community meetings these science objectives drove the conceptual design of instruments studied by the COR Program Office during July September 2012. This RFI submission encapsulates the results of that study, and suggests that a more detailed look into the instrument suite should be conducted to prove viability and affordability to support the demonstrated scientific value. This study was conducted in the context of a larger effort to consider the options available for a mission to dispose safely of Hubble hence, the overall architecture considered for the mission we studied for the 2.4m telescope asset included resource sharing. This mitigates combined cost and risk and provides naturally for a continued US leadership role in astrophysics with an advanced, general-purpose UV visible space telescope.
González-Romá, Vicente; Hernández, Ana
2014-11-01
We investigated whether climate uniformity (the pattern of climate perceptions of organizational support within the team) is related to task conflict, team communication quality, and team performance. We used a sample composed of 141 bank branches and collected data at 3 time points. The results obtained showed that, after controlling for aggregate team climate, climate strength, and their interaction, a type of nonuniform climate pattern (weak dissimilarity) was directly related to task conflict and team communication quality. Teams with weak dissimilarity nonuniform patterns tended to show higher levels of task conflict and lower levels of team communication quality than teams with uniform climate patterns. The relationship between weak dissimilarity patterns and team performance was fully mediated by team communication quality. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
HUBBLE STAYS ON TRAIL OF FADING GAMMA-RAY BURST FIREBALL
2002-01-01
A Hubble Space Telescope image of the fading fireball from one of the universe's most mysterious phenomena, a gamma-ray burst. Though the visible component has faded to 1/500th its brightness (27.7 magnitude) from the time it was first discovered by ground- based telescopes last March (the actual gamma-ray burst took place on February 28), Hubble continues to clearly see the fireball and discriminated a surrounding nebulosity (at 25th magnitude) which is considered a host galaxy. The continued visibility of the burst, and the rate of its fading, support theories that the light from a gamma-ray burst is an expanding relativistic (moving near the speed of light) fireball, possibly produced by the collision of two dense objects, such as an orbiting pair of neutron stars. If the burst happened nearby, within our own galaxy, the resulting fireball should have had only enough energy to propel it into space for a month. The fact that this fireball is still visible after six months means the explosion was truly titanic and, to match the observed brightness, must have happened at the vast distances of galaxies. The energy released in a burst, which can last from a fraction of a second to a few hundred seconds, is equal to all of the Sun's energy generated over its 10 billion year lifetime. The false-color image was taken Sept. 5, 1997 with the Space Telescope Imaging Spectrograph. Credit: Andrew Fruchter (STScI), Elena Pian (ITSRE-CNR), and NASA
[Developing team reflexivity as a learning and working tool for medical teams].
Riskin, Arieh; Bamberger, Peter
2014-01-01
Team reflexivity is a collective activity in which team members review their previous work, and develop ideas on how to modify their work behavior in order to achieve better future results. It is an important learning tool and a key factor in explaining the varying effectiveness of teams. Team reflexivity encompasses both self-awareness and agency, and includes three main activities: reflection, planning, and adaptation. The model of briefing-debriefing cycles promotes team reflexivity. Its key elements include: Pre-action briefing--setting objectives, roles, and strategies the mission, as well as proposing adaptations based on what was previously learnt from similar procedures; Post-action debriefing--reflecting on the procedure performed and reviewing the extent to which objectives were met, and what can be learnt for future tasks. Given the widespread attention to team-based work systems and organizational learning, efforts should be made toward ntroducing team reflexivity in health administration systems. Implementation could be difficult because most teams in hospitals are short-lived action teams formed for a particular event, with limited time and opportunity to consciously reflect upon their actions. But it is precisely in these contexts that reflexive processes have the most to offer instead of the natural impulsive collective logics. Team reflexivity suggests a potential solution to the major problems of iatorgenesis--avoidable medical errors, as it forces all team members to participate in a reflexive process together. Briefing-debriefing technology was studied mainly in surgical teams and was shown to enhance team-based learning and to improve quality-related outcomes and safety.
“Team Building: Proven Strategies for Improving Team Performance, 4th Edition”
Directory of Open Access Journals (Sweden)
Greg Homan
2008-12-01
Full Text Available Team Building is an important issue for Youth Development professionals. We utilize team-focused work to achieve our objectives in educating youth. The team building skills we integrate into programming serve to prepare youth for the dynamic, highly interpersonal work environment of today. “Team Building: Proven Strategies for Improving Team Performance, 4th Edition,” by W. Dyer, W.G. Dyer, and J. Dyer (2007, provides a practical theoretical framework for those interested in team building application, training, and practice in everyday work.
Isabella, Lynn A.
2005-01-01
This article chronicles the unique manner in which a second-year MBA elective course in managing teams has been crafted using existing first-year learning teams as its core. The design and orchestration of this course are detailed, as are the challenges posed, in delivering a course that not only teaches about teams and team dynamics but does so…
Charge retention test experiences on Hubble Space Telescope nickel-hydrogen battery cells
Nawrocki, Dave E.; Driscoll, J. R.; Armantrout, J. D.; Baker, R. C.; Wajsgras, H.
1993-01-01
The Hubble Space Telescope (HST) nickel-hydrogen battery module was designed by Lockheed Missile & Space Co (LMSC) and manufactured by Eagle-Picher Ind. (EPI) for the Marshall Space Flight Center (MSFC) as an Orbital Replacement Unit (ORU) for the nickel-cadmium batteries originally selected for this low earth orbit mission. The design features of the HST nickel hydrogen battery are described and the results of an extended charge retention test are summarized.
Using artificial team members for team training in virtual environments
Diggelen, J. van; Muller, T.; Bosch, K. van den
2010-01-01
In a good team, members do not only perform their individual task, they also coordinate their actions with other members of the team. Developing such team skills usually involves exercises with all members playing their role. This approach is costly and has organizational and educational drawbacks.
Directory of Open Access Journals (Sweden)
Katherine Gibbard
2017-11-01
Full Text Available With the knowledge that team work is not always associated with high(er performance, we draw from the Multi-Level Theory of Psychological Contracts, Person-Environment Fit Theory, and Optimal Distinctiveness Theory to study shared perceptions of psychological contract (PC breach in relation to shared perceptions of complementary and supplementary fit to explain why some teams perform better than other teams. We collected three repeated survey measures in a sample of 128 respondents across 46 teams. After having made sure that we met all statistical criteria, we aggregated our focal variables to the team-level and analyzed our data by means of a longitudinal three-wave autoregressive moderated-mediation model in which each relationship was one-time lag apart. We found that shared perceptions of PC breach were directly negatively related to team output and negatively related to perceived team member effectiveness through a decrease in shared perceptions of supplementary fit. However, we also demonstrated a beneficial process in that shared perceptions of PC breach were positively related to shared perceptions of complementary fit, which in turn were positively related to team output. Moreover, best team output appeared in teams that could combine high shared perceptions of complementary fit with modest to high shared perceptions of supplementary fit. Overall, our findings seem to indicate that in terms of team output there may be a bright side to perceptions of PC breach and that perceived person-team fit may play an important role in this process.
The Hubble Constant to 1%: Physics beyond LambdaCDM
Riess, Adam
2017-08-01
By steadily advancing the precision and accuracy of the Hubble constant, we now see 3.4-sigma evidence for a deviation from the standard LambdaCDM model and thus the exciting chance of discovering new fundamental physics such as exotic dark energy, a new relativistic particle, dark matter interactions, or a small curvature, to name a few possibilities. We propose a coordinated program to accomplish three goals with one set of observations: (1) improve the precision of the best route to H_0 with HST observations of Cepheids in the hosts of 11 SNe Ia, lowering the uncertainty to 1.3% to reach the discovery threshold of 5-sigma and begin resolving the underlying source of the deviation; (2) continue testing the quality of Cepheid distances, so far the most accurate and reliable indicators in the near Universe, using the tip of the red giant branch (TRGB); and (3) use oxygen-rich Miras to confirm the present tension with the CMB and establish a future route available to JWST. We can achieve all three goals with one dataset and take the penultimate step to reach 1% precision in H_0 after Gaia. With its long-pass filter and NIR capability, we can collect these data with WFC3 many times faster than previously possible while overcoming the extinction and metallicity effects that challenged the first generation of H_0 measurements. Our results will complement the leverage available at high redshift from other cosmological tools such as BAO, the CMB, and SNe Ia, and will provide a 40% improvement on the WFIRST measurements of dark energy. Reaching this precision will be a fitting legacy for the telescope charged to resolve decades of uncertainty regarding the Hubble constant.
Teams as innovative systems: multilevel motivational antecedents of innovation in R&D teams.
Chen, Gilad; Farh, Jiing-Lih; Campbell-Bush, Elizabeth M; Wu, Zhiming; Wu, Xin
2013-11-01
Integrating theories of proactive motivation, team innovation climate, and motivation in teams, we developed and tested a multilevel model of motivators of innovative performance in teams. Analyses of multisource data from 428 members of 95 research and development (R&D) teams across 33 Chinese firms indicated that team-level support for innovation climate captured motivational mechanisms that mediated between transformational leadership and team innovative performance, whereas members' motivational states (role-breadth self-efficacy and intrinsic motivation) mediated between proactive personality and individual innovative performance. Furthermore, individual motivational states and team support for innovation climate uniquely promoted individual innovative performance, and, in turn, individual innovative performance linked team support for innovation climate to team innovative performance. (c) 2013 APA, all rights reserved.
International Nuclear Information System (INIS)
Sasou, Kunihide; Hirose, Ayako; Misawa, Ryou; Yamaguchi, Hiroyuki
2006-01-01
The series of this study describes the necessity of the evaluation of team work from two aspects of operator's behavior and operators' mind. The authors propose Team Work Element Model which consists of necessary elements to build high performance team. This report discusses a method to evaluate team work from the second aspect, that is, competency trust, competition, for-the team spirit, etc. The authors survey the previous studies on psychological measures and organize a set of questions to evaluate 10 team work sub elements that are the parts of Team Work Element Model. The factor analysis shows that this set of questions is consists of 13 factors such as task-oriented leadership, harmony-oriented team atmosphere, etc. Close examination of the questions in each factor shows that 8 of 10 team work sub elements can be evaluated by this questionnaire. In addition, this questionnaire comprises scales additional 8 scales such as job satisfaction, leadership, etc. As a result, it is possible to evaluate team work from more comprehensive view points. (author)
Second generation spectrograph for the Hubble Space Telescope
Woodgate, B. E.; Boggess, A.; Gull, T. R.; Heap, S. R.; Krueger, V. L.; Maran, S. P.; Melcher, R. W.; Rebar, F. J.; Vitagliano, H. D.; Green, R. F.; Wolff, S. C.; Hutchings, J. B.; Jenkins, E. B.; Linsky, J. L.; Moos, H. W.; Roesler, F.; Shine, R. A.; Timothy, J. G.; Weistrop, D. E.; Bottema, M.; Meyer, W.
1986-01-01
The preliminary design for the Space Telescope Imaging Spectrograph (STIS), which has been selected by NASA for definition study for future flight as a second-generation instrument on the Hubble Space Telescope (HST), is presented. STIS is a two-dimensional spectrograph that will operate from 1050 A to 11,000 A at the limiting HST resolution of 0.05 arcsec FWHM, with spectral resolutions of 100, 1200, 20,000, and 100,000 and a maximum field-of-view of 50 x 50 arcsec. Its basic operating modes include echelle model, long slit mode, slitless spectrograph mode, coronographic spectroscopy, photon time-tagging, and direct imaging. Research objectives are active galactic nuclei, the intergalactic medium, global properties of galaxies, the origin of stellar systems, stelalr spectral variability, and spectrographic mapping of solar system processes.
Savelsbergh, Chantal M.J.H.; Poell, Rob F.; van der Heijden, Beatrice
2014-01-01
An exploratory field study was conducted among 30 project teams in the sectors of building and utilities, engineering and construction, infrastructure, and area decontamination and development in the Netherlands. It examined the influence of leadership on team learning behaviors and included team
Savelsbergh, C.; Poell, R.F.; van der Heijden, B.
2015-01-01
An exploratory field study was conducted among 30 project teams in the sectors of building and utilities, engineering and construction, infrastructure, and area decontamination and development in the Netherlands. It examined the influence of leadership on team learning behaviors and included team
Initial Hubble Diagram Results from the Nearby Supernova Factory
Energy Technology Data Exchange (ETDEWEB)
Bailey, S. [Lab. Nuclear and High-Energy Physics (LPNHE), Paris (France); Aldering, G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Antilogus, P. [Lab. Nuclear and High-Energy Physics (LPNHE), Paris (France); Aragon, C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Baltay, C. [Yale Univ., New Haven, CT (United States); Bongard, S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Buton, C [Inst. of Nuclear Physics of Lyon (France); Childress, M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Copin, Y. [Inst. of Nuclear Physics of Lyon (France); Gangler, E. [Inst. of Nuclear Physics of Lyon (France); Loken, S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nugent, P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Pain, R. [Lab. Nuclear and High-Energy Physics (LPNHE), Paris (France); Pecontal, E. [Center of Research Astrophysics of Lyon (CRAL) (France); Pereira, R. [Lab. Nuclear and High-Energy Physics (LPNHE), Paris (France); Perlmutter, S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rabinowitz, D. [Yale Univ., New Haven, CT (United States); Rigaudier, G. [Center of Research Astrophysics of Lyon (CRAL) (France); Ripoche, P. [Lab. Nuclear and High-Energy Physics (LPNHE), Paris (France); Runge, K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Scalzo, R. [Yale Univ., New Haven, CT (United States); Smadja, G. [Inst. of Nuclear Physics of Lyon (France); Tao, C. [Inst. of Nuclear Physics of Lyon (France); Thomas, R. C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wu, C. [Lab. Nuclear and High-Energy Physics (LPNHE), Paris (France)
2017-07-06
The use of Type Ia supernovae as distance indicators led to the discovery of the accelerating expansion of the universe a decade ago. Now that large second generation surveys have significantly increased the size and quality of the high-redshift sample, the cosmological constraints are limited by the currently available sample of ~50 cosmologically useful nearby supernovae. The Nearby Supernova Factory addresses this problem by discovering nearby supernovae and observing their spectrophotometric time development. Our data sample includes over 2400 spectra from spectral timeseries of 185 supernovae. This talk presents results from a portion of this sample including a Hubble diagram (relative distance vs. redshift) and a description of some analyses using this rich dataset.
Using team cognitive work analysis to reveal healthcare team interactions in a birthing unit.
Ashoori, Maryam; Burns, Catherine M; d'Entremont, Barbara; Momtahan, Kathryn
2014-01-01
Cognitive work analysis (CWA) as an analytical approach for examining complex sociotechnical systems has shown success in modelling the work of single operators. The CWA approach incorporates social and team interactions, but a more explicit analysis of team aspects can reveal more information for systems design. In this paper, Team CWA is explored to understand teamwork within a birthing unit at a hospital. Team CWA models are derived from theories and models of teamwork and leverage the existing CWA approaches to analyse team interactions. Team CWA is explained and contrasted with prior approaches to CWA. Team CWA does not replace CWA, but supplements traditional CWA to more easily reveal team information. As a result, Team CWA may be a useful approach to enhance CWA in complex environments where effective teamwork is required. This paper looks at ways of analysing cognitive work in healthcare teams. Team Cognitive Work Analysis, when used to supplement traditional Cognitive Work Analysis, revealed more team information than traditional Cognitive Work Analysis. Team Cognitive Work Analysis should be considered when studying teams.
Using team cognitive work analysis to reveal healthcare team interactions in a birthing unit
Ashoori, Maryam; Burns, Catherine M.; d'Entremont, Barbara; Momtahan, Kathryn
2014-01-01
Cognitive work analysis (CWA) as an analytical approach for examining complex sociotechnical systems has shown success in modelling the work of single operators. The CWA approach incorporates social and team interactions, but a more explicit analysis of team aspects can reveal more information for systems design. In this paper, Team CWA is explored to understand teamwork within a birthing unit at a hospital. Team CWA models are derived from theories and models of teamworkand leverage the existing CWA approaches to analyse team interactions. Team CWA is explained and contrasted with prior approaches to CWA. Team CWA does not replace CWA, but supplements traditional CWA to more easily reveal team information. As a result, Team CWA may be a useful approach to enhance CWA in complex environments where effective teamwork is required. Practitioner Summary: This paper looks at ways of analysing cognitive work in healthcare teams. Team Cognitive Work Analysis, when used to supplement traditional Cognitive Work Analysis, revealed more team information than traditional Cognitive Work Analysis. Team Cognitive Work Analysis should be considered when studying teams PMID:24837514
Courtright, Stephen H; McCormick, Brian W; Mistry, Sal; Wang, Jiexin
2017-10-01
Though prevalent in practice, team charters have only recently received scholarly attention. However, most of this work has been relatively devoid of theory, and consequently, key questions about why and under what conditions team charter quality affects team performance remain unanswered. To address these gaps, we draw on macro organizational control theory to propose that team charter quality serves as a team-level "behavior" control mechanism that builds task cohesion through a structured exercise. We then juxtapose team charter quality with an "input" team control mechanism that influences the emergence of task cohesion more organically: team conscientiousness. Given their redundant effects on task cohesion, we propose that the effects of team charter quality and team conscientiousness on team performance (through task cohesion) are substitutive such that team charter quality primarily impacts team performance for teams that are low (vs. high) on conscientiousness. We test and find support for our hypotheses in a sample of 239 undergraduate self-managing project teams. Our study contributes to the groups and teams literature in the following ways: first, relative to previous studies, we take a more theory-driven approach toward understanding team charters, and in doing so, uncover when and why team charter quality impacts team performance; second, we integrate two normally disparate perspectives on team effectiveness (team development and team selection) to offer a broader perspective on how teams are "built"; and third, we introduce team charter quality as a performance-enhancing mechanism for teams lower on conscientiousness. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Directory of Open Access Journals (Sweden)
Kathy Egea
Full Text Available Specialists who work in a globalised environment, need to work in teams, if they are to be continuously effective. The challenge for IT educators is to design and implement inter-cultural teamwork practices into their curriculum. Investigating this challenge, this case study describes Team Health, an assessment approach designed to skill students to be more effective in team working in cross-cultural and cross-discipline teams. The educational context is teamwork practice within a first year introductory web design course. Framed by Saunders\\'s virtual team lifecycle model (relationship building and team processes and Hofstede\\'s cultural dimensions (communication and working cross-culturally, the assessment approach utilises reflective and iterative strategies to support team working. At three points in the semester, students complete a survey on these four concepts, identify team strengths and weaknesses from the results of the surveys and work towards addressing one team weakness. The final assessment activity requires students to reflect on team working for the semester. Key attributes for effective team working are identified from the three surveys and the final reflective summaries. This paper compares course outcomes such as team cohesion and student grades to the previous course offering and shows that with the introduction of Team Health, the more complex student cohorts under this study achieve equally well. It is concluded that the guided reflective practices underpinning Team Health can prepare students for first year approaches to teamwork, and thereby provide starting points for working in future global teams where members are both culturally diverse and from different discipline areas.
The Relationships between Work Team Strategic Intent and Work Team Performance
National Research Council Canada - National Science Library
Edison, Thomas R
2007-01-01
...) executive level, six- week program management class in six different locations. The study not only underscores the significance of team focus on performance but also highlights how team characteristics affect team focus and performance...
Fransen, K; Steffens, N K; Haslam, S A; Vanbeselaere, N; Vande Broek, G; Boen, F
2016-12-01
The present research examines the impact of leaders' confidence in their team on the team confidence and performance of their teammates. In an experiment involving newly assembled soccer teams, we manipulated the team confidence expressed by the team leader (high vs neutral vs low) and assessed team members' responses and performance as they unfolded during a competition (i.e., in a first baseline session and a second test session). Our findings pointed to team confidence contagion such that when the leader had expressed high (rather than neutral or low) team confidence, team members perceived their team to be more efficacious and were more confident in the team's ability to win. Moreover, leaders' team confidence affected individual and team performance such that teams led by a highly confident leader performed better than those led by a less confident leader. Finally, the results supported a hypothesized mediational model in showing that the effect of leaders' confidence on team members' team confidence and performance was mediated by the leader's perceived identity leadership and members' team identification. In conclusion, the findings of this experiment suggest that leaders' team confidence can enhance members' team confidence and performance by fostering members' identification with the team. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Energy Technology Data Exchange (ETDEWEB)
Miller, M.A.
1996-08-01
Teamwork is the key to the future of effective technology management. Today`s technologies and markets have become too complex for individuals to work alone. Global competition, limited resources, cost consciousness, and time pressures have forced organizations and project managers to encourage teamwork. Many of these teams will be cross-functional teams that can draw on a multitude of talents and knowledge. To develop high-performing cross-functional teams, managers must understand motivations, functional loyalties, and the different backgrounds of the individual team members. To develop a better understanding of these issues, managers can learn from experience and from literature on teams and teaming concepts. When studying the literature to learn about cross-functional teaming, managers will find many good theoretical concepts, but when put into practice, these concepts have varying effects. This issue of varying effectiveness is what drives the research for this paper. The teaming concepts were studied to confirm or modify current understanding. The literature was compared with a {open_quotes}ground truth{close_quotes}, a survey of the reality of teaming practices, to examine the teaming concepts that the literature finds to be critical to the success of teams. These results are compared to existing teams to determine if such techniques apply in real-world cases.
Jarrett, Steven M; Glaze, Ryan M; Schurig, Ira; Arthur, Winfred
2017-08-01
The relationship between team sex composition and team performance on a complex psychomotor task was examined because these types of tasks are commonly used in the lab-based teams literature. Despite well-documented sex-based differences on complex psychomotor tasks, the preponderance of studies-mainly lab based-that use these tasks makes no mention of the sex composition of teams across or within experimental conditions. A sample of 123 four-person teams with varying team sex composition learned and performed a complex psychomotor task, Steal Beasts Pro PE. Each team completed a 5-hr protocol whereby they conducted several performance missions. The results indicated significant large mean differences such that teams with larger proportions of males had higher performance scores. These findings demonstrate the potential effect of team sex composition on the validity of studies that use complex psychomotor tasks to explore and investigate team performance-related phenomena when (a) team sex composition is not a focal variable of interest and (b) it is not accounted for or controlled. Given the proclivity of complex psychomotor action-based tasks used in lab-based team studies, it is important to understand and control for the impact of team sex composition on team performance. When team sex composition is not controlled for, either methodologically or statistically, it may affect the validity of the results in teams studies using these types of tasks.
Tiferes, Judith; Bisantz, Ann M
2018-04-01
Many studies on teams report measures of team communication; however, these studies vary widely in terms of the team characteristics, situations, and tasks studied making it difficult to understand impacts on team communication more generally. The objective of this review is systematically summarize relationships between measures of team communication and team characteristics and situational contexts. A literature review was conducted searching in four electronic databases (PsycINFO, MEDLINE, Ergonomics Abstracts, and SocINDEX). Additional studies were identified by cross-referencing. Articles included for final review had reported at least one team communication measure associated with some team and/or context dimension. Ninety-nine of 727 articles met the inclusion criteria. Data extracted from articles included characteristics of the studies and teams and the nature of each of the reported team and/or context dimensions-team communication properties relationships. Some dimensions (job role, situational stressors, training strategies, cognitive artifacts, and communication media) were found to be consistently linked to changes in team communication. A synthesized diagram that describes the possible associations between eleven team and context dimensions and nine team communication measures is provided along with research needs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Automation of Hubble Space Telescope Mission Operations
Burley, Richard; Goulet, Gregory; Slater, Mark; Huey, William; Bassford, Lynn; Dunham, Larry
2012-01-01
On June 13, 2011, after more than 21 years, 115 thousand orbits, and nearly 1 million exposures taken, the operation of the Hubble Space Telescope successfully transitioned from 24x7x365 staffing to 815 staffing. This required the automation of routine mission operations including telemetry and forward link acquisition, data dumping and solid-state recorder management, stored command loading, and health and safety monitoring of both the observatory and the HST Ground System. These changes were driven by budget reductions, and required ground system and onboard spacecraft enhancements across the entire operations spectrum, from planning and scheduling systems to payload flight software. Changes in personnel and staffing were required in order to adapt to the new roles and responsibilities required in the new automated operations era. This paper will provide a high level overview of the obstacles to automating nominal HST mission operations, both technical and cultural, and how those obstacles were overcome.
DEFF Research Database (Denmark)
Hoda, Rashina; Babb, Jeff; Nørbjerg, Jacob
2013-01-01
to sacrifice learning-focused practices. Effective learning under pressure involves conscious efforts to implement original agile practices such as retrospectives and adapted strategies such as learning spikes. Teams, their management, and customers must all recognize the importance of creating learning teams......Today's software development challenges require learning teams that can continuously apply new engineering and management practices, new and complex technical skills, cross-functional skills, and experiential lessons learned. The pressure of delivering working software often forces software teams...
MANAGING MULTICULTURAL PROJECT TEAMS
Directory of Open Access Journals (Sweden)
Cezar SCARLAT
2014-06-01
Full Text Available The article is based on literature review and authors’ own recent experience in managing multicultural project teams, in international environment. This comparative study considers two groups of projects: technical assistance (TA projects versus information technology (IT projects. The aim is to explore the size and structure of the project teams – according to the team formation and its lifecycle, and to identify some distinctive attributes of the project teams – both similarities and differences between the above mentioned types of projects. Distinct focus of the research is on the multiculturalism of the project teams: how the cultural background of the team members influences the team performance and team management. Besides the results of the study are the managerial implications: how the team managers could soften the cultural clash, and avoid inter-cultural misunderstandings and even conflicts – in order to get a better performance. Some practical examples are provided as well.
Task versus relationship conflict, team performance, and team member satisfaction: a meta-analysis.
De Dreu, Carsten K W; Weingart, Laurie R
2003-08-01
This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, results revealed strong and negative correlations between relationship conflict, team performance, and team member satisfaction. In contrast to what has been suggested in both academic research and introductory textbooks, however, results also revealed strong and negative (instead of the predicted positive) correlations between task conflict team performance, and team member satisfaction. As predicted, conflict had stronger negative relations with team performance in highly complex (decision making, project, mixed) than in less complex (production) tasks. Finally, task conflict was less negatively related to team performance when task conflict and relationship conflict were weakly, rather than strongly, correlated.
... Games. USA Hockey offers additional information and resources. Softball It's not easy to field full teams of ... an annual tournament sponsored by the National Wheelchair Softball Association , where thirty or so teams show up ...
Study on dynamic team performance evaluation methodology based on team situation awareness model
International Nuclear Information System (INIS)
Kim, Suk Chul
2005-02-01
The purpose of this thesis is to provide a theoretical framework and its evaluation methodology of team dynamic task performance of operating team at nuclear power plant under the dynamic and tactical environment such as radiological accident. This thesis suggested a team dynamic task performance evaluation model so called team crystallization model stemmed from Endsely's situation awareness model being comprised of four elements: state, information, organization, and orientation and its quantification methods using system dynamics approach and a communication process model based on a receding horizon control approach. The team crystallization model is a holistic approach for evaluating the team dynamic task performance in conjunction with team situation awareness considering physical system dynamics and team behavioral dynamics for a tactical and dynamic task at nuclear power plant. This model provides a systematic measure to evaluate time-dependent team effectiveness or performance affected by multi-agents such as plant states, communication quality in terms of transferring situation-specific information and strategies for achieving the team task goal at given time, and organizational factors. To demonstrate the applicability of the proposed model and its quantification method, the case study was carried out using the data obtained from a full-scope power plant simulator for 1,000MWe pressurized water reactors with four on-the-job operating groups and one expert group who knows accident sequences. Simulated results team dynamic task performance with reference key plant parameters behavior and team-specific organizational center of gravity and cue-and-response matrix illustrated good symmetry with observed value. The team crystallization model will be useful and effective tool for evaluating team effectiveness in terms of recruiting new operating team for new plant as cost-benefit manner. Also, this model can be utilized as a systematic analysis tool for
Study on dynamic team performance evaluation methodology based on team situation awareness model
Energy Technology Data Exchange (ETDEWEB)
Kim, Suk Chul
2005-02-15
The purpose of this thesis is to provide a theoretical framework and its evaluation methodology of team dynamic task performance of operating team at nuclear power plant under the dynamic and tactical environment such as radiological accident. This thesis suggested a team dynamic task performance evaluation model so called team crystallization model stemmed from Endsely's situation awareness model being comprised of four elements: state, information, organization, and orientation and its quantification methods using system dynamics approach and a communication process model based on a receding horizon control approach. The team crystallization model is a holistic approach for evaluating the team dynamic task performance in conjunction with team situation awareness considering physical system dynamics and team behavioral dynamics for a tactical and dynamic task at nuclear power plant. This model provides a systematic measure to evaluate time-dependent team effectiveness or performance affected by multi-agents such as plant states, communication quality in terms of transferring situation-specific information and strategies for achieving the team task goal at given time, and organizational factors. To demonstrate the applicability of the proposed model and its quantification method, the case study was carried out using the data obtained from a full-scope power plant simulator for 1,000MWe pressurized water reactors with four on-the-job operating groups and one expert group who knows accident sequences. Simulated results team dynamic task performance with reference key plant parameters behavior and team-specific organizational center of gravity and cue-and-response matrix illustrated good symmetry with observed value. The team crystallization model will be useful and effective tool for evaluating team effectiveness in terms of recruiting new operating team for new plant as cost-benefit manner. Also, this model can be utilized as a systematic analysis tool for
Attributions by Team Members for Team Outcomes in Finnish Working Life
Valo, Maarit; Hurme, Pertti
2010-01-01
This study focuses on teamwork in Finnish working life. Through a wide cross-section of teams the study examines the causes to which team members attribute the outcomes of their teams. Qualitative data was collected from 314 respondents. They wrote 616 stories to describe memorable experiences of success and failure in teamwork. The stories revealed 1930 explanations. The findings indicate that both favorable and unfavorable team outcomes are perceived as being caused by ...
Jang, In Sung; Hatt, Dylan; Beaton, Rachael L.; Lee, Myung Gyoon; Freedman, Wendy L.; Madore, Barry F.; Hoyt, Taylor J.; Monson, Andrew J.; Rich, Jeffrey A.; Scowcroft, Victoria; Seibert, Mark
2018-01-01
The Carnegie–Chicago Hubble Program (CCHP) seeks to anchor the distance scale of Type Ia supernovae via the Tip of the Red Giant Branch (TRGB) method. Based on deep Hubble Space Telescope ACS/WFC imaging, we present an analysis of the TRGB for the metal-poor halo of NGC 1365, a giant spiral galaxy in the Fornax cluster that was host to the Type Ia supernova SN 2012fr. We have measured the extinction-corrected TRGB magnitude of NGC 1365 to be F814W = 27.34 ± 0.03stat ± 0.04sys mag. In advance of future direct calibration by Gaia, we adopt a provisional I-band TRGB luminosity set at the Large Magellanic Cloud and find a true distance modulus μ 0 = 31.29 ± 0.04stat ± 0.06sys mag or D = 18.1 ± 0.3stat ± 0.5sys Mpc. This measurement is in excellent agreement with recent Cepheid-based distances to NGC 1365 and reveals no significant difference in the distances derived from stars of Populations I and II for this galaxy. We revisit the error budget for the CCHP path to the Hubble constant based on the analysis presented here, i.e., that for one of the most distant Type Ia supernova hosts within our Program, and find that a 2.5% measurement is feasible with the current sample of galaxies and TRGB absolute calibration. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program #13691.
A Measure of Team Resilience: Developing the Resilience at Work Team Scale.
McEwen, Kathryn; Boyd, Carolyn M
2018-03-01
This study develops, and initial evaluates, a new measure of team-based resilience for use in research and practice. We conducted preliminary analyses, based on a cross-sectional sample of 344 employees nested within 31 teams. Seven dimensions were identified through exploratory and confirmatory factor analyses. The measure had high reliability and significant discrimination to indicate the presence of a unique team-based aspect of resilience that contributed to higher work engagement and higher self-rated team performance, over and above the effects of individual resilience. Multilevel analyses showed that team, but not individual, resilience predicted self-rated team performance. Practice implications include a need to focus on collective as well as individual behaviors in resilience-building. The measure provides a diagnostic instrument for teams and a scale to evaluate organizational interventions and research the relationship of resilience to other constructs.
A Conceptual Framework for Team Social Capital as Basis for Organizational Team Synergy
Raluca ZOLTAN
2012-01-01
The purpose of this paper is to outline a conceptual framework of team social capital as a basis for reaching organizational team synergy. The dimensions of team social capital and the basic conditions required for organizational team synergy enable the extension of current model of team social capital by including of other variables. Today’s managers must consider these variables since the team tends to be the basic structural unit of current organizations and synergy, the key to achieving h...
Kuziemsky, Craig E; Borycki, Elizabeth M; Purkis, Mary Ellen; Black, Fraser; Boyle, Michael; Cloutier-Fisher, Denise; Fox, Lee Ann; MacKenzie, Patricia; Syme, Ann; Tschanz, Coby; Wainwright, Wendy; Wong, Helen
2009-09-15
There are few studies that examine the processes that interdisciplinary teams engage in and how we can design health information systems (HIS) to support those team processes. This was an exploratory study with two purposes: (1) To develop a framework for interdisciplinary team communication based on structures, processes and outcomes that were identified as having occurred during weekly team meetings. (2) To use the framework to guide 'e-teams' HIS design to support interdisciplinary team meeting communication. An ethnographic approach was used to collect data on two interdisciplinary teams. Qualitative content analysis was used to analyze the data according to structures, processes and outcomes. We present details for team meta-concepts of structures, processes and outcomes and the concepts and sub concepts within each meta-concept. We also provide an exploratory framework for interdisciplinary team communication and describe how the framework can guide HIS design to support 'e-teams'. The structures, processes and outcomes that describe interdisciplinary teams are complex and often occur in a non-linear fashion. Electronic data support, process facilitation and team video conferencing are three HIS tools that can enhance team function.
Directory of Open Access Journals (Sweden)
MacKenzie Patricia
2009-09-01
Full Text Available Abstract Background There are few studies that examine the processes that interdisciplinary teams engage in and how we can design health information systems (HIS to support those team processes. This was an exploratory study with two purposes: (1 To develop a framework for interdisciplinary team communication based on structures, processes and outcomes that were identified as having occurred during weekly team meetings. (2 To use the framework to guide 'e-teams' HIS design to support interdisciplinary team meeting communication. Methods An ethnographic approach was used to collect data on two interdisciplinary teams. Qualitative content analysis was used to analyze the data according to structures, processes and outcomes. Results We present details for team meta-concepts of structures, processes and outcomes and the concepts and sub concepts within each meta-concept. We also provide an exploratory framework for interdisciplinary team communication and describe how the framework can guide HIS design to support 'e-teams'. Conclusion The structures, processes and outcomes that describe interdisciplinary teams are complex and often occur in a non-linear fashion. Electronic data support, process facilitation and team video conferencing are three HIS tools that can enhance team function.
Travelling with football teams
African Journals Online (AJOL)
ultimately on the performance of the teams on the playing field and not so much ... However, travelling with a football team presents the team physician .... physician to determine the nutritional ..... diarrhoea in elite athletes: an audit of one team.
Gatlin, Kenda
2005-01-01
Almost anyone has held various roles on a team, be it a family unit, sports team, or a project-oriented team. As an educator, one must make a conscious decision to build and invest in a team. Gathering the best team possible will help one achieve one's goals. This article explores some of the key reasons why it is important to focus on the team…
A Conceptual Framework for Team Social Capital as Basis for Organizational Team Synergy
Directory of Open Access Journals (Sweden)
Raluca ZOLTAN
2012-08-01
Full Text Available The purpose of this paper is to outline a conceptual framework of team social capital as a basis for reaching organizational team synergy. The dimensions of team social capital and the basic conditions required for organizational team synergy enable the extension of current model of team social capital by including of other variables. Today’s managers must consider these variables since the team tends to be the basic structural unit of current organizations and synergy, the key to achieving high performance in global competition.
Building the team for team science
Read, Emily K.; O'Rourke, M.; Hong, G. S.; Hanson, P. C.; Winslow, Luke A.; Crowley, S.; Brewer, C. A.; Weathers, K. C.
2016-01-01
The ability to effectively exchange information and develop trusting, collaborative relationships across disciplinary boundaries is essential for 21st century scientists charged with solving complex and large-scale societal and environmental challenges, yet these communication skills are rarely taught. Here, we describe an adaptable training program designed to increase the capacity of scientists to engage in information exchange and relationship development in team science settings. A pilot of the program, developed by a leader in ecological network science, the Global Lake Ecological Observatory Network (GLEON), indicates that the training program resulted in improvement in early career scientists’ confidence in team-based network science collaborations within and outside of the program. Fellows in the program navigated human-network challenges, expanded communication skills, and improved their ability to build professional relationships, all in the context of producing collaborative scientific outcomes. Here, we describe the rationale for key communication training elements and provide evidence that such training is effective in building essential team science skills.
Roberts, Nicole K; Williams, Reed G; Schwind, Cathy J; Sutyak, John A; McDowell, Christopher; Griffen, David; Wall, Jarrod; Sanfey, Hilary; Chestnut, Audra; Meier, Andreas H; Wohltmann, Christopher; Clark, Ted R; Wetter, Nathan
2014-02-01
Communication breakdowns and care coordination problems often cause preventable adverse patient care events, which can be especially acute in the trauma setting, in which ad hoc teams have little time for advanced planning. Existing teamwork curricula do not address the particular issues associated with ad hoc emergency teams providing trauma care. Ad hoc trauma teams completed a preinstruction simulated trauma encounter and were provided with instruction on appropriate team behaviors and team communication. Teams completed a postinstruction simulated trauma encounter immediately afterward and 3 weeks later, then completed a questionnaire. Blinded raters rated videotapes of the simulations. Participants expressed high levels of satisfaction and intent to change practice after the intervention. Participants changed teamwork and communication behavior on the posttest, and changes were sustained after a 3-week interval, though there was some loss of retention. Brief training exercises can change teamwork and communication behaviors on ad hoc trauma teams. Copyright © 2014 Elsevier Inc. All rights reserved.
Future Time Perspective in Occupational Teams: Do Older Workers Prefer More Familiar Teams?
Directory of Open Access Journals (Sweden)
Laura U. A. Gärtner
2017-09-01
Full Text Available Working in teams is quite popular across different industries and cultures. While some of these teams exist for longer time periods, other teams collaborate only for short periods and members switch into new teams after goals are accomplished. However, workers’ preferences for joining a new team might vary in different ways. Based on Carstensen’s socioemotional selectivity theory, we predict that emotionally meaningful teams are prioritized when occupational future time perspective (OFTP is perceived as limited. Building and expanding on studies outside of the work context, we expected that older as compared to younger workers prefer more familiar teams, and that this effect is mediated by workers’ OFTP. Moreover, we assumed that experimentally manipulated OFTP can change such team preferences. The hypotheses were tested in an online scenario study using three experimental conditions (within-person design. Four hundred and fifty-four workers (57% female, age M = 45.98, SD = 11.46 were asked to choose between a familiar and a new team in three consecutive trials: under an unspecified OFTP (baseline, under an expanded OFTP (amendment of retirement age, and under a restricted OFTP (insolvency of the current company. Whereas the baseline condition was always first, the order of the second and third conditions was randomized among participants. In the baseline condition, results showed the expected mediation effect of workers’ OFTP on the relation between workers’ age and preference for a familiar over a new team. Higher age was associated with more limited OFTP, which in turn was associated with higher preference for a familiar over a new team. Moreover, experimentally restricting OFTP increased preference for a familiar team over a new team regardless of workers’ age, providing further evidence for the assumed causal processes and showing interesting avenues for practical interventions in occupational teams.
Future Time Perspective in Occupational Teams: Do Older Workers Prefer More Familiar Teams?
Gärtner, Laura U. A.; Hertel, Guido
2017-01-01
Working in teams is quite popular across different industries and cultures. While some of these teams exist for longer time periods, other teams collaborate only for short periods and members switch into new teams after goals are accomplished. However, workers’ preferences for joining a new team might vary in different ways. Based on Carstensen’s socioemotional selectivity theory, we predict that emotionally meaningful teams are prioritized when occupational future time perspective (OFTP) is perceived as limited. Building and expanding on studies outside of the work context, we expected that older as compared to younger workers prefer more familiar teams, and that this effect is mediated by workers’ OFTP. Moreover, we assumed that experimentally manipulated OFTP can change such team preferences. The hypotheses were tested in an online scenario study using three experimental conditions (within-person design). Four hundred and fifty-four workers (57% female, age M = 45.98, SD = 11.46) were asked to choose between a familiar and a new team in three consecutive trials: under an unspecified OFTP (baseline), under an expanded OFTP (amendment of retirement age), and under a restricted OFTP (insolvency of the current company). Whereas the baseline condition was always first, the order of the second and third conditions was randomized among participants. In the baseline condition, results showed the expected mediation effect of workers’ OFTP on the relation between workers’ age and preference for a familiar over a new team. Higher age was associated with more limited OFTP, which in turn was associated with higher preference for a familiar over a new team. Moreover, experimentally restricting OFTP increased preference for a familiar team over a new team regardless of workers’ age, providing further evidence for the assumed causal processes and showing interesting avenues for practical interventions in occupational teams. PMID:29018376
Future Time Perspective in Occupational Teams: Do Older Workers Prefer More Familiar Teams?
Gärtner, Laura U A; Hertel, Guido
2017-01-01
Working in teams is quite popular across different industries and cultures. While some of these teams exist for longer time periods, other teams collaborate only for short periods and members switch into new teams after goals are accomplished. However, workers' preferences for joining a new team might vary in different ways. Based on Carstensen's socioemotional selectivity theory, we predict that emotionally meaningful teams are prioritized when occupational future time perspective (OFTP) is perceived as limited. Building and expanding on studies outside of the work context, we expected that older as compared to younger workers prefer more familiar teams, and that this effect is mediated by workers' OFTP. Moreover, we assumed that experimentally manipulated OFTP can change such team preferences. The hypotheses were tested in an online scenario study using three experimental conditions (within-person design). Four hundred and fifty-four workers (57% female, age M = 45.98, SD = 11.46) were asked to choose between a familiar and a new team in three consecutive trials: under an unspecified OFTP (baseline), under an expanded OFTP (amendment of retirement age), and under a restricted OFTP (insolvency of the current company). Whereas the baseline condition was always first, the order of the second and third conditions was randomized among participants. In the baseline condition, results showed the expected mediation effect of workers' OFTP on the relation between workers' age and preference for a familiar over a new team. Higher age was associated with more limited OFTP, which in turn was associated with higher preference for a familiar over a new team. Moreover, experimentally restricting OFTP increased preference for a familiar team over a new team regardless of workers' age, providing further evidence for the assumed causal processes and showing interesting avenues for practical interventions in occupational teams.
Fransen, Katrien; Coffee, Pete; Vanbeselaere, Norbert; Slater, Matthew; De Cuyper, Bert; Boen, Filip
2014-01-01
Research on the effect of athlete leadership on pre-cursors of team performance such as team confidence is sparse. To explore the underlying mechanisms of how athlete leaders impact their team’s confidence, an online survey was completed by 2,867 players and coaches from nine different team sports in Flanders (Belgium). We distinguished between two types of team confidence: collective efficacy, assessed by the CEQS subscales of Effort, Persistence, Preparation, and Unity; and team outcome con...
Dark energy and the quietness of the local Hubble flow
International Nuclear Information System (INIS)
Axenides, M.; Perivolaropoulos, L.
2002-01-01
The linearity and quietness of the local ( X (t 0 ) of dark energy obeying the time independent equation of state p X =wρ X . We find that dark energy can indeed cool the LHF. However the dark energy parameter values required to make the predicted velocity dispersion consistent with the observed value v rms ≅40 km/s have been ruled out by other observational tests constraining the dark energy parameters w and Ω X . Therefore despite the claims of recent qualitative studies, dark energy with time independent equation of state cannot by itself explain the quietness and linearity of the local Hubble flow
Complex Problem Solving in Teams: The Impact of Collective Orientation on Team Process Demands.
Hagemann, Vera; Kluge, Annette
2017-01-01
Complex problem solving is challenging and a high-level cognitive process for individuals. When analyzing complex problem solving in teams, an additional, new dimension has to be considered, as teamwork processes increase the requirements already put on individual team members. After introducing an idealized teamwork process model, that complex problem solving teams pass through, and integrating the relevant teamwork skills for interdependently working teams into the model and combining it with the four kinds of team processes (transition, action, interpersonal, and learning processes), the paper demonstrates the importance of fulfilling team process demands for successful complex problem solving within teams. Therefore, results from a controlled team study within complex situations are presented. The study focused on factors that influence action processes, like coordination, such as emergent states like collective orientation, cohesion, and trust and that dynamically enable effective teamwork in complex situations. Before conducting the experiments, participants were divided by median split into two-person teams with either high ( n = 58) or low ( n = 58) collective orientation values. The study was conducted with the microworld C3Fire, simulating dynamic decision making, and acting in complex situations within a teamwork context. The microworld includes interdependent tasks such as extinguishing forest fires or protecting houses. Two firefighting scenarios had been developed, which takes a maximum of 15 min each. All teams worked on these two scenarios. Coordination within the team and the resulting team performance were calculated based on a log-file analysis. The results show that no relationships between trust and action processes and team performance exist. Likewise, no relationships were found for cohesion. Only collective orientation of team members positively influences team performance in complex environments mediated by action processes such as
Leading team learning: what makes interprofessional teams learn to work well?
Chatalalsingh, Carole; Reeves, Scott
2014-11-01
This article describes an ethnographic study focused on exploring leaders of team learning in well-established nephrology teams in an academic healthcare organization in Canada. Employing situational theory of leadership, the article provides details on how well established team members advance as "learning leaders". Data were gathered by ethnographic methods over a 9-month period with the members of two nephrology teams. These learning to care for the sick teams involved over 30 regulated health professionals, such as physicians, nurses, social workers, pharmacists, dietitians and other healthcare practitioners, staff, students and trainees, all of whom were collectively managing obstacles and coordinating efforts. Analysis involved an inductive thematic analysis of observations, reflections, and interview transcripts. The study indicated how well established members progress as team-learning leaders, and how they adapt to an interprofessional culture through the activities they employ to enable day-to-day learning. The article uses situational theory of leadership to generate a detailed illumination of the nature of leaders' interactions within an interprofessional context.
Collocation Impact on Team Effectiveness
Directory of Open Access Journals (Sweden)
M Eccles
2010-11-01
Full Text Available The collocation of software development teams is common, specially in agile software development environments. However little is known about the impact of collocation on the team’s effectiveness. This paper explores the impact of collocating agile software development teams on a number of team effectiveness factors. The study focused on South African software development teams and gathered data through the use of questionnaires and interviews. The key finding was that collocation has a positive impact on a number of team effectiveness factors which can be categorised under team composition, team support, team management and structure and team communication. Some of the negative impact collocation had on team effectiveness relate to the fact that team members perceived that less emphasis was placed on roles, that morale of the group was influenced by individuals, and that collocation was invasive, reduced level of privacy and increased frequency of interruptions. Overall through it is proposed that companies should consider collocating their agile software development teams, as collocation might leverage overall team effectiveness.
Otter, den A.F.H.J.; Emmitt, S.
2007-01-01
Purpose – Effective teams use a balance of synchronous and asynchronous communication. Team communication is dependent on the communication acts of team members and the ability of managers to facilitate, stimulate and motivate them. Team members from organizations using different information systems
Managing Geographically Dispersed Teams: From Temporary to Permanent Global Virtual Teams
DEFF Research Database (Denmark)
Svane Hansen, Tine; Hope, Alexander John; Moehler, Robert C.
2012-01-01
for organisations to move towards establishing permanent Global Virtual Teams in order to leverage knowledge sharing and cooperation across distance. To close this gap, this paper will set the scene for a research project investigating the changed preconditions for organisations. As daily face-to-face communication......The rise and spread of information communication technologies (ICT) has enabled increasing use of geographically dispersed work teams (Global Virtual Teams). Originally, Global Virtual Teams were mainly organised into temporary projects. Little research has focused on the emergent challenge...... generation of self-lead digital natives, who are already practising virtual relationships and a new approach to work, and currently joining the global workforce; and improved communication technologies. Keywords: Global Virtual teams, ICT, leadership, motivation, self-management, millenials....
VizieR Online Data Catalog: Hubble Source Catalog (V1 and V2) (Whitmore+, 2016)
Whitmore, B. C.; Allam, S. S.; Budavari, T.; Casertano, S.; Downes, R. A.; Donaldson, T.; Fall, S. M.; Lubow, S. H.; Quick, L.; Strolger, L.-G.; Wallace, G.; White, R. L.
2016-10-01
The HSC v1 contains members of the WFPC2, ACS/WFC, WFC3/UVIS and WFC3/IR Source Extractor source lists from HLA version DR8 (data release 8). The crossmatching process involves adjusting the relative astrometry of overlapping images so as to minimize positional offsets between closely aligned sources in different images. After correction, the astrometric residuals of crossmatched sources are significantly reduced, to typically less than 10mas. The relative astrometry is supported by using Pan-STARRS, SDSS, and 2MASS as the astrometric backbone for initial corrections. In addition, the catalog includes source nondetections. The crossmatching algorithms and the properties of the initial (Beta 0.1) catalog are described in Budavari & Lubow (2012ApJ...761..188B). The HSC v2 contains members of the WFPC2, ACS/WFC, WFC3/UVIS and WFC3/IR Source Extractor source lists from HLA version DR9.1 (data release 9.1). The crossmatching process involves adjusting the relative astrometry of overlapping images so as to minimize positional offsets between closely aligned sources in different images. After correction, the astrometric residuals of crossmatched sources are significantly reduced, to typically less than 10mas. The relative astrometry is supported by using Pan-STARRS, SDSS, and 2MASS as the astrometric backbone for initial corrections. In addition, the catalog includes source nondetections. The crossmatching algorithms and the properties of the initial (Beta 0.1) catalog are described in Budavari & Lubow (2012ApJ...761..188B). Hubble Source Catalog Acknowledgement: Based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESAC/ESA) and the Canadian Astronomy Data Centre (CADC/NRC/CSA). (2 data files).
How Team-Level and Individual-Level Conflict Influences Team Commitment: A Multilevel Investigation
Lee, Sanghyun; Kwon, Seungwoo; Shin, Shung J.; Kim, MinSoo; Park, In-Jo
2018-01-01
We investigate how two different types of conflict (task conflict and relationship conflict) at two different levels (individual-level and team-level) influence individual team commitment. The analysis was conducted using data we collected from 193 employees in 31 branch offices of a Korean commercial bank. The relationships at multiple levels were tested using hierarchical linear modeling (HLM). The results showed that individual-level relationship conflict was negatively related to team commitment while individual-level task conflict was not. In addition, both team-level task and relationship conflict were negatively associated with team commitment. Finally, only team-level relationship conflict significantly moderated the relationship between individual-level relationship conflict and team commitment. We further derive theoretical implications of these findings. PMID:29387033
How Team-Level and Individual-Level Conflict Influences Team Commitment: A Multilevel Investigation
Directory of Open Access Journals (Sweden)
Sanghyun Lee
2018-01-01
Full Text Available We investigate how two different types of conflict (task conflict and relationship conflict at two different levels (individual-level and team-level influence individual team commitment. The analysis was conducted using data we collected from 193 employees in 31 branch offices of a Korean commercial bank. The relationships at multiple levels were tested using hierarchical linear modeling (HLM. The results showed that individual-level relationship conflict was negatively related to team commitment while individual-level task conflict was not. In addition, both team-level task and relationship conflict were negatively associated with team commitment. Finally, only team-level relationship conflict significantly moderated the relationship between individual-level relationship conflict and team commitment. We further derive theoretical implications of these findings.
National Research Council Canada - National Science Library
Cobb, Marshall
1999-01-01
This study examined how manipulating the level of environmental complexity and the type of team training given to subject volunteers impacted important team process behaviors and performance outcomes...
76 FR 42683 - Establishment of a Team Under the National Construction Safety Team Act
2011-07-19
...-01] Establishment of a Team Under the National Construction Safety Team Act AGENCY: National..., announces the establishment of a National Construction Safety Team pursuant to the National Construction Safety Team Act. The Team was established to study the effects of the tornado that touched down in Joplin...
Stillman, Jennifer A; Fletcher, Richard B; Carr, Stuart C
2007-04-01
Research on groups is often applied to sport teams, and research on teams is often applied to groups. This study investigates the extent to which individuals have distinct schemas for groups and teams. A list of team and group characteristics was generated from 250 individuals, for use in this and related research. Questions about teams versus groups carry an a priori implication that differences exist; therefore, list items were presented to new participants and were analyzed using signal detection theory, which can accommodate a finding of no detectable difference between a nominated category and similar items. Participants were 30 members from each of the following: netball teams, the general public, and hobby groups. Analysis revealed few features that set groups apart from teams; however, teams were perceived as more structured and demanding, requiring commitment and effort toward shared goals. Team and group characteristics were more clearly defined to team members than they were to other participant groups. The research has implications for coaches and practitioners.
Luciano, Margaret M; Mathieu, John E; Ruddy, Thomas M
2014-03-01
External leaders continue to be an important source of influence even when teams are empowered, but it is not always clear how they do so. Extending research on structurally empowered teams, we recognize that teams' external leaders are often responsible for multiple teams. We adopt a multilevel approach to model external leader influences at both the team level and the external leader level of analysis. In doing so, we distinguish the influence of general external leader behaviors (i.e., average external leadership) from those that are directed differently toward the teams that they lead (i.e., relative external leadership). Analysis of data collected from 451 individuals, in 101 teams, reporting to 25 external leaders, revealed that both relative and average external leadership related positively to team empowerment. In turn, team empowerment related positively to team performance and member job satisfaction. However, while the indirect effects were all positive, we found that relative external leadership was not directly related to team performance, and average external leadership evidenced a significant negative direct influence. Additionally, relative external leadership exhibited a significant direct positive influence on member job satisfaction as anticipated, whereas average external leadership did not. These findings attest to the value in distinguishing external leaders' behaviors that are exhibited consistently versus differentially across empowered teams. Implications and future directions for the study and management of external leaders overseeing multiple teams are discussed.
Staff Turnover in Assertive Community Treatment (Act) Teams: The Role of Team Climate.
Zhu, Xi; Wholey, Douglas R; Cain, Cindy; Natafgi, Nabil
2017-03-01
Staff turnover in Assertive Community Treatment (ACT) teams can result in interrupted services and diminished support for clients. This paper examines the effect of team climate, defined as team members' shared perceptions of their work environment, on turnover and individual outcomes that mediate the climate-turnover relationship. We focus on two climate dimensions: safety and quality climate and constructive conflict climate. Using survey data collected from 26 ACT teams, our analyses highlight the importance of safety and quality climate in reducing turnover, and job satisfaction as the main mediator linking team climate to turnover. The findings offer practical implications for team management.
Energy Technology Data Exchange (ETDEWEB)
Li, Hai-Li; Zhang, Jing-Fei; Feng, Lu [Northeastern University, Department of Physics, College of Sciences, Shenyang (China); Zhang, Xin [Northeastern University, Department of Physics, College of Sciences, Shenyang (China); Peking University, Center for High Energy Physics, Beijing (China)
2017-12-15
In this paper, we make a deep analysis for the five typical interacting holographic dark energy models with the interaction terms Q = 3βH{sub 0}ρ{sub de}, Q = 3βH{sub 0}ρ{sub c}, Q = 3βH{sub 0}(ρ{sub de} + ρ{sub c}), Q = 3βH{sub 0}√(ρ{sub de}ρ{sub c}), and Q = 3βH{sub 0}(ρ{sub de}ρ{sub c})/(ρ{sub de}+ρ{sub c}), respectively. We obtain observational constraints on these models by using the type Ia supernova data (the Joint Light-Curve Analysis sample), the cosmic microwave background data (Planck 2015 distance priors), the baryon acoustic oscillations data, and the direct measurement of the Hubble constant. We find that the values of χ{sub min}{sup 2} for all the five models are almost equal (around 699), indicating that the current observational data equally favor these IHDE models. In addition, a comparison with the cases of an interaction term involving the Hubble parameter H is also made. (orig.)
Complex Problem Solving in Teams: The Impact of Collective Orientation on Team Process Demands
Hagemann, Vera; Kluge, Annette
2017-01-01
Complex problem solving is challenging and a high-level cognitive process for individuals. When analyzing complex problem solving in teams, an additional, new dimension has to be considered, as teamwork processes increase the requirements already put on individual team members. After introducing an idealized teamwork process model, that complex problem solving teams pass through, and integrating the relevant teamwork skills for interdependently working teams into the model and combining it with the four kinds of team processes (transition, action, interpersonal, and learning processes), the paper demonstrates the importance of fulfilling team process demands for successful complex problem solving within teams. Therefore, results from a controlled team study within complex situations are presented. The study focused on factors that influence action processes, like coordination, such as emergent states like collective orientation, cohesion, and trust and that dynamically enable effective teamwork in complex situations. Before conducting the experiments, participants were divided by median split into two-person teams with either high (n = 58) or low (n = 58) collective orientation values. The study was conducted with the microworld C3Fire, simulating dynamic decision making, and acting in complex situations within a teamwork context. The microworld includes interdependent tasks such as extinguishing forest fires or protecting houses. Two firefighting scenarios had been developed, which takes a maximum of 15 min each. All teams worked on these two scenarios. Coordination within the team and the resulting team performance were calculated based on a log-file analysis. The results show that no relationships between trust and action processes and team performance exist. Likewise, no relationships were found for cohesion. Only collective orientation of team members positively influences team performance in complex environments mediated by action processes such as
Complex Problem Solving in Teams: The Impact of Collective Orientation on Team Process Demands
Directory of Open Access Journals (Sweden)
Vera Hagemann
2017-09-01
Full Text Available Complex problem solving is challenging and a high-level cognitive process for individuals. When analyzing complex problem solving in teams, an additional, new dimension has to be considered, as teamwork processes increase the requirements already put on individual team members. After introducing an idealized teamwork process model, that complex problem solving teams pass through, and integrating the relevant teamwork skills for interdependently working teams into the model and combining it with the four kinds of team processes (transition, action, interpersonal, and learning processes, the paper demonstrates the importance of fulfilling team process demands for successful complex problem solving within teams. Therefore, results from a controlled team study within complex situations are presented. The study focused on factors that influence action processes, like coordination, such as emergent states like collective orientation, cohesion, and trust and that dynamically enable effective teamwork in complex situations. Before conducting the experiments, participants were divided by median split into two-person teams with either high (n = 58 or low (n = 58 collective orientation values. The study was conducted with the microworld C3Fire, simulating dynamic decision making, and acting in complex situations within a teamwork context. The microworld includes interdependent tasks such as extinguishing forest fires or protecting houses. Two firefighting scenarios had been developed, which takes a maximum of 15 min each. All teams worked on these two scenarios. Coordination within the team and the resulting team performance were calculated based on a log-file analysis. The results show that no relationships between trust and action processes and team performance exist. Likewise, no relationships were found for cohesion. Only collective orientation of team members positively influences team performance in complex environments mediated by action processes
Revisiting the stellar velocity ellipsoid-Hubble-type relation: observations versus simulations
Pinna, F.; Falcón-Barroso, J.; Martig, M.; Martínez-Valpuesta, I.; Méndez-Abreu, J.; van de Ven, G.; Leaman, R.; Lyubenova, M.
2018-04-01
The stellar velocity ellipsoid (SVE) in galaxies can provide important information on the processes that participate in the dynamical heating of their disc components (e.g. giant molecular clouds, mergers, spiral density waves, and bars). Earlier findings suggested a strong relation between the shape of the disc SVE and Hubble type, with later-type galaxies displaying more anisotropic ellipsoids and early types being more isotropic. In this paper, we revisit the strength of this relation using an exhaustive compilation of observational results from the literature on this issue. We find no clear correlation between the shape of the disc SVE and morphological type, and show that galaxies with the same Hubble type display a wide range of vertical-to-radial velocity dispersion ratios. The points are distributed around a mean value and scatter of σz/σR = 0.7 ± 0.2. With the aid of numerical simulations, we argue that different mechanisms might influence the shape of the SVE in the same manner and that the same process (e.g. mergers) does not have the same impact in all the galaxies. The complexity of the observational picture is confirmed by these simulations, which suggest that the vertical-to-radial axis ratio of the SVE is not a good indicator of the main source of disc heating. Our analysis of those simulations also indicates that the observed shape of the disc SVE may be affected by several processes simultaneously and that the signatures of some of them (e.g. mergers) fade over time.
Team-based global organizations
DEFF Research Database (Denmark)
Zander, Lena; Butler, Christina; Mockaitis, Audra
2015-01-01
diversity in enhancing team creativity and performance, and 2) the sharing of knowledge in team-based organizations, while the other two themes address global team leadership: 3) the unprecedented significance of social capital for the success of global team leader roles; and 4) the link between shared......This chapter draws on a panel discussion of the future of global organizing as a team-based organization at EIBA 2014 in Uppsala, Sweden. We began by discussing contemporary developments of hybrid forms of hierarchy and teams-based organizing, but we venture to propose that as organizations become...... characterized by decreased importance of hierarchal structures, more fluidity across borders, even a possible dissolution of firm boundaries, we move towards team-based organizing as an alternative to more traditional forms of hierarchical-based organizing in global firms. To provide input for a discussion...
Team Creativity: The Effects of Perceived Learning Culture, Developmental Feedback and Team Cohesion
Joo, Baek-Kyoo; Song, Ji Hoon; Lim, Doo Hun; Yoon, Seung Won
2012-01-01
This study investigates the influence of perceived learning culture, developmental feedback and team cohesion on team creativity. The results showed that the demographic variables, the three antecedents and their interactions explained 41 per cent of variance in team creativity. Team creativity was positively correlated with a higher level of…
Mach's Principle to Hubble's Law and Light Relativity
Zhang, Tianxi
2018-01-01
Discovery of the redshift-distance relation to be linear (i.e. Hubble's law) for galaxies in the end of 1920s instigated us to widely accept expansion of the universe, originated from a big bang around 14 billion years ago. Finding of the redshift-distance relation to be weaker than linear for distant type Ia supernovae nearly two decades ago further precipitated us to largely agree with recent acceleration of the universe, driven by the mysterious dark energy. The time dilation measured for supernovae has been claimed as a direct evidence for the expansion of the universe, but scientists could not explain why quasars and gamma-ray bursts had not similar time dilations. Recently, an anomaly was found in the standard template for the width of supernova light curves to be proportional to the wavelength, which exactly removed the time dilation of supernovae and hence was strongly inconsistent with the conventional redshift mechanism. In this study, we have derived a new redshift-distance relation from Mach's principle with light relativity that describes the effect of light on spacetime as well as the influence of disturbed spacetime on the light inertia or frequency. A moving object or photon, because of its continuously keeping on displacement, disturbs the rest of the entire universe or distorts/curves the spacetime. The distorted or curved spacetime then generates an effective gravitational force to act back on the moving object or photon, so that reduces the object inertia or photon frequency. Considering the disturbance of spacetime by a photon is extremely weak, we have modelled the effective gravitational force to be Newtonian and derived the new redshift-distance relation that can not only perfectly explain the redshift-distance measurement of distant type Ia supernovae but also inherently obtain Hubble's law as an approximate at small redshift. Therefore, the result obtained from this study does neither support the acceleration of the universe nor the
The bigger they are, the harder they fall: linking team power, team conflict, and performance
Greer, L.L.; Caruso, H.M.; Jehn, K.A.
2011-01-01
Across two field studies, we investigate the impact of team power on team conflict and performance. Team power is based on the control of resources that enables a team to influence others in the company. We find across both studies that low-power teams outperform high-power teams. In both studies,
Stimulating teachers’ team performance through team-oriented HR practices
Bouwmans, Machiel; Runhaar, Piety; Wesselink, Renate; Mulder, Martin
2017-01-01
Teams of teachers are increasingly held accountable for the quality of education and educational reforms in vocational education and training institutions. However, historically teachers have not been required to engage in deep-level collaboration, thus team-oriented HR practices are being used
STS 31 PAYLOAD HUBBLE SPACE TELESCOPE ENCLOSED IN AN AIR-TIGHT PLASTIC BAG FOR PROTECTION IN VERTICA
1989-01-01
Preparations are made to enclose the Hubble Space Telescope [HST] inside an air-tight plastic bag in the VPF. Processing of the 94- inch primary mirror telescope for launch on the Discovery in March 1990, involves working within strict controls to prevent contamination.
Ability Dispersion and Team Performance
DEFF Research Database (Denmark)
Hoogendoorn, Sander; Parker, Simon C.; Van Praag, Mirjam
What is the effect of dispersed levels of cognitive ability of members of a (business) team on their team's performance? This paper reports the results of a field experiment in which 573 students in 49 (student) teams start up and manage real companies under identical circumstances for one year. We...... ensured exogenous variation in otherwise random team composition by assigning students to teams based on their measured cognitive abilities. Each team performs a variety of tasks, often involving complex decision making. The key result of the experiment is that the performance of business teams first...... increases and then decreases with ability dispersion. We seek to understand this finding by developing a model in which team members of different ability levels form sub- teams with other team members with similar ability levels to specialize in different productive tasks. Diversity spreads production over...
Edmondson, Amy; Bohmer, Richard; Pisano, Gary
2001-01-01
A study of 16 cardiac surgery teams looked at how the teams adapted to new ways of working. The challenge of team management is to implement new processes as quickly as possible. Steps for creating a learning team include selecting a mix of skills and expertise, framing the challenge, and creating an environment of psychological safety. (JOW)
Diversity in goal orientation, team reflexivity, and team performance
Pieterse, Anne Nederveen; van Knippenberg, Daan; van Ginkel, Wendy P.
Although recent research highlights the role of team member goal orientation in team functioning, research has neglected the effects of diversity in goal orientation. In a laboratory study with groups working on a problem-solving task, we show that diversity in learning and performance orientation
Monaghan, Conal; Bizumic, Boris; Reynolds, Katherine; Smithson, Michael; Johns-Boast, Lynette; van Rooy, Dirk
2015-01-01
One prominent approach in the exploration of the variations in project team performance has been to study two components of the aggregate personalities of the team members: conscientiousness and agreeableness. A second line of research, known as self-categorisation theory, argues that identifying as team members and the team's performance norms should substantially influence the team's performance. This paper explores the influence of both these perspectives in university software engineering project teams. Eighty students worked to complete a piece of software in small project teams during 2007 or 2008. To reduce limitations in statistical analysis, Monte Carlo simulation techniques were employed to extrapolate from the results of the original sample to a larger simulated sample (2043 cases, within 319 teams). The results emphasise the importance of taking into account personality (particularly conscientiousness), and both team identification and the team's norm of performance, in order to cultivate higher levels of performance in student software engineering project teams.
Trauma teams and time to early management during in situ trauma team training.
Härgestam, Maria; Lindkvist, Marie; Jacobsson, Maritha; Brulin, Christine; Hultin, Magnus
2016-01-29
To investigate the association between the time taken to make a decision to go to surgery and gender, ethnicity, years in profession, experience of trauma team training, experience of structured trauma courses and trauma in the trauma team, as well as use of closed-loop communication and leadership styles during trauma team training. In situ trauma team training. The patient simulator was preprogrammed to represent a severely injured patient (injury severity score: 25) suffering from hypovolemia due to external trauma. An emergency room in an urban Scandinavian level one trauma centre. A total of 96 participants were divided into 16 trauma teams. Each team consisted of six team members: one surgeon/emergency physician (designated team leader), one anaesthesiologist, one registered nurse anaesthetist, one registered nurse from the emergency department, one enrolled nurse from the emergency department and one enrolled nurse from the operating theatre. HRs with CIs (95% CI) for the time taken to make a decision to go to surgery was computed from a Cox proportional hazards model. Three variables remained significant in the final model. Closed-loop communication initiated by the team leader increased the chance of a decision to go to surgery (HR: 3.88; CI 1.02 to 14.69). Only 8 of the 16 teams made the decision to go to surgery within the timeframe of the trauma team training. Conversely, call-outs and closed-loop communication initiated by the team members significantly decreased the chance of a decision to go to surgery, (HR: 0.82; CI 0.71 to 0.96, and HR: 0.23; CI 0.08 to 0.71, respectively). Closed-loop communication initiated by the leader appears to be beneficial for teamwork. In contrast, a high number of call-outs and closed-loop communication initiated by team members might lead to a communication overload. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
DEFF Research Database (Denmark)
den Otter, Ad; Emmitt, Stephen
2007-01-01
Effective teams use a balance of synchronous and asynchronous communication. Team communication is dependent on the communication acts of team members and the ability of managers to facilitate, stimulate and motivate them. Team members from organizations using different information systems tend...... to have different understanding, opinions, and rates of adoption and skills levels regarding specific IT tools. The purpose of this paper is to explore the effective use of tools for communication in design teams and the strategies for the use of specific tools....
Team structure and regulatory focus: the impact of regulatory fit on team dynamic.
Dimotakis, Nikolaos; Davison, Robert B; Hollenbeck, John R
2012-03-01
We report a within-teams experiment testing the effects of fit between team structure and regulatory task demands on task performance and satisfaction through average team member positive affect and helping behaviors. We used a completely crossed repeated-observations design in which 21 teams enacted 2 tasks with different regulatory focus characteristics (prevention and promotion) in 2 organizational structures (functional and divisional), resulting in 84 observations. Results suggested that salient regulatory demands inherent in the task interacted with structure to determine objective and subjective team-level outcomes, such that functional structures were best suited to (i.e., had best fit with) tasks with a prevention regulatory focus and divisional structures were best suited to tasks with a promotion regulatory focus. This contingency finding integrates regulatory focus and structural contingency theories, and extends them to the team level with implications for models of performance, satisfaction, and team dynamics.
Homan, Astrid C; Buengeler, Claudia; Eckhoff, Robert A; van Ginkel, Wendy P; Voelpel, Sven C
2015-09-01
Attaining value from nationality diversity requires active diversity management, which organizations often employ in the form of diversity training programs. Interestingly, however, the previously reported effects of diversity training are often weak and, sometimes, even negative. This situation calls for research on the conditions under which diversity training helps or harms teams. We propose that diversity training can increase team creativity, but only for teams with less positive pretraining diversity beliefs (i.e., teams with a greater need for such training) and that are sufficiently diverse in nationality. Comparing the creativity of teams that attended nationality diversity training versus control training, we found that for teams with less positive diversity beliefs, diversity training increased creative performance when the team's nationality diversity was high, but undermined creativity when the team's nationality diversity was low. Diversity training had less impact on teams with more positive diversity beliefs, and training effects were not contingent upon these teams' diversity. Speaking to the underlying process, we showed that these interactive effects were driven by the experienced team efficacy of the team members. We discuss theoretical and practical implications for nationality diversity management. (c) 2015 APA, all rights reserved).
Gender Composition of Tactical Decision Making Teams; Impact on Team Process and Outcome
National Research Council Canada - National Science Library
Elliott, Linda
1997-01-01
This study investigates the performance of teams differing in gender composition on a university-developed synthetic task, the Team Interactive Decision Exercise for Teams Incorporating Distributed Expertise (TIDE2...
Model of Team Organization and Behavior and Team Description Method
1984-10-01
PERFORMING ORG& REPORT’ NUMBER 7.AUTHIOR(&) 0. CONTRACT OR GRANT NUMOSR(ej J. Thomas Roth Rohn J. Hritz HDA 903-81-C-0198: VEa Donald W. McGill 9...team descriptions are included, acid procedures for data recording are provided. 4q-4 4 iv, G OP S• . . • ,," $1 . . ’ __ _ _ _ ’ / . • , Utilization...Listing of thi! number acid identification of the roles adopted by team members in the actual team structure, along with KOS and primary equipment
Implementation of a team-based learning course: Work required and perceptions of the teaching team.
Morris, Jenny
2016-11-01
Team-based learning was selected as a strategy to help engage pre-registration undergraduate nursing students in a second-year evidence-informed decision making course. To detail the preparatory work required to deliver a team-based learning course; and to explore the perceptions of the teaching team of their first experience using team-based learning. Descriptive evaluation. Information was extracted from a checklist and process document developed by the course leader to document the work required prior to and during implementation. Members of the teaching team were interviewed by a research assistant at the end of the course using a structured interview schedule to explore perceptions of first time implementation. There were nine months between the time the decision was made to use team-based learning and the first day of the course. Approximately 60days were needed to reconfigure the course for team-based learning delivery, develop the knowledge and expertise of the teaching team, and develop and review the resources required for the students and the teaching team. This reduced to around 12days for the subsequent delivery. Interview data indicated that the teaching team were positive about team-based learning, felt prepared for the course delivery and did not identify any major problems during this first implementation. Implementation of team-based learning required time and effort to prepare the course materials and the teaching team. The teaching team felt well prepared, were positive about using team-based learning and did not identify any major difficulties. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
... gov/ency/patientinstructions/000929.htm Your cancer care team To use the sharing features on this page, ... help your body heal. Working with Your Care Team Each member of your care team plays an ...
West, Courtney; Landry, Karen; Graham, Anna; Graham, Lori; Cianciolo, Anna T; Kalet, Adina; Rosen, Michael; Sherman, Deborah Witt
2015-01-01
SGEA 2015 CONFERENCE ABSTRACT (EDITED). Evaluating Interprofessional Teamwork During a Large-Scale Simulation. Courtney West, Karen Landry, Anna Graham, and Lori Graham. CONSTRUCT: This study investigated the multidimensional measurement of interprofessional (IPE) teamwork as part of large-scale simulation training. Healthcare team function has a direct impact on patient safety and quality of care. However, IPE team training has not been the norm. Recognizing the importance of developing team-based collaborative care, our College of Nursing implemented an IPE simulation activity called Disaster Day and invited other professions to participate. The exercise consists of two sessions: one in the morning and another in the afternoon. The disaster scenario is announced just prior to each session, which consists of team building, a 90-minute simulation, and debriefing. Approximately 300 Nursing, Medicine, Pharmacy, Emergency Medical Technicians, and Radiology students and over 500 standardized and volunteer patients participated in the Disaster Day event. To improve student learning outcomes, we created 3 competency-based instruments to evaluate collaborative practice in multidimensional fashion during this exercise. A 20-item IPE Team Observation Instrument designed to assess interprofessional team's attainment of Interprofessional Education Collaborative (IPEC) competencies was completed by 20 faculty and staff observing the Disaster Day simulation. One hundred sixty-six standardized patients completed a 10-item Standardized Patient IPE Team Evaluation Instrument developed from the IPEC competencies and adapted items from the 2014 Henry et al. PIVOT Questionnaire. This instrument assessed the standardized or volunteer patient's perception of the team's collaborative performance. A 29-item IPE Team's Perception of Collaborative Care Questionnaire, also created from the IPEC competencies and divided into 5 categories of Values/Ethics, Roles and Responsibilities
2010-08-12
Strategies to Enhance Online Learning Teams Team Assessment and Diagnostics Instrument and Agent-based Modeling Tristan E. Johnson, Ph.D. Learning ...REPORT DATE AUG 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND SUBTITLE Strategies to Enhance Online Learning ...TeamsTeam Strategies to Enhance Online Learning Teams: Team Assessment and Diagnostics Instrument and Agent-based Modeling 5a. CONTRACT NUMBER 5b. GRANT
Determinants of team-sport performance: implications for altitude training by team-sport athletes
Bishop, David J; Girard, Olivier
2013-01-01
Team sports are increasingly popular, with millions of participants worldwide. Athletes engaged in these sports are required to repeatedly produce skilful actions and maximal or near-maximal efforts (eg, accelerations, changes in pace and direction, sprints, jumps and kicks), interspersed with brief recovery intervals (consisting of rest or low-intensity to moderate-intensity activity), over an extended period of time (1–2 h). While performance in most team sports is dominated by technical and tactical proficiencies, successful team-sport athletes must also have highly-developed, specific, physical capacities. Much effort goes into designing training programmes to improve these physical capacities, with expected benefits for team-sport performance. Recently, some team sports have introduced altitude training in the belief that it can further enhance team-sport physical performance. Until now, however, there is little published evidence showing improved team-sport performance following altitude training, despite the often considerable expense involved. In the absence of such studies, this review will identify important determinants of team-sport physical performance that may be improved by altitude training, with potential benefits for team-sport performance. These determinants can be broadly described as factors that enhance either sprint performance or the ability to recover from maximal or near-maximal efforts. There is some evidence that some of these physical capacities may be enhanced by altitude training, but further research is required to verify that these adaptations occur, that they are greater than what could be achieved by appropriate sea-level training and that they translate to improved team-sport performance. PMID:24282200
Determinants of team-sport performance: implications for altitude training by team-sport athletes.
Bishop, David J; Girard, Olivier
2013-12-01
Team sports are increasingly popular, with millions of participants worldwide. Athletes engaged in these sports are required to repeatedly produce skilful actions and maximal or near-maximal efforts (eg, accelerations, changes in pace and direction, sprints, jumps and kicks), interspersed with brief recovery intervals (consisting of rest or low-intensity to moderate-intensity activity), over an extended period of time (1-2 h). While performance in most team sports is dominated by technical and tactical proficiencies, successful team-sport athletes must also have highly-developed, specific, physical capacities. Much effort goes into designing training programmes to improve these physical capacities, with expected benefits for team-sport performance. Recently, some team sports have introduced altitude training in the belief that it can further enhance team-sport physical performance. Until now, however, there is little published evidence showing improved team-sport performance following altitude training, despite the often considerable expense involved. In the absence of such studies, this review will identify important determinants of team-sport physical performance that may be improved by altitude training, with potential benefits for team-sport performance. These determinants can be broadly described as factors that enhance either sprint performance or the ability to recover from maximal or near-maximal efforts. There is some evidence that some of these physical capacities may be enhanced by altitude training, but further research is required to verify that these adaptations occur, that they are greater than what could be achieved by appropriate sea-level training and that they translate to improved team-sport performance.
Trauma team leaders' non-verbal communication: video registration during trauma team training.
Härgestam, Maria; Hultin, Magnus; Brulin, Christine; Jacobsson, Maritha
2016-03-25
There is widespread consensus on the importance of safe and secure communication in healthcare, especially in trauma care where time is a limiting factor. Although non-verbal communication has an impact on communication between individuals, there is only limited knowledge of how trauma team leaders communicate. The purpose of this study was to investigate how trauma team members are positioned in the emergency room, and how leaders communicate in terms of gaze direction, vocal nuances, and gestures during trauma team training. Eighteen trauma teams were audio and video recorded during trauma team training in the emergency department of a hospital in northern Sweden. Quantitative content analysis was used to categorize the team members' positions and the leaders' non-verbal communication: gaze direction, vocal nuances, and gestures. The quantitative data were interpreted in relation to the specific context. Time sequences of the leaders' gaze direction, speech time, and gestures were identified separately and registered as time (seconds) and proportions (%) of the total training time. The team leaders who gained control over the most important area in the emergency room, the "inner circle", positioned themselves as heads over the team, using gaze direction, gestures, vocal nuances, and verbal commands that solidified their verbal message. Changes in position required both attention and collaboration. Leaders who spoke in a hesitant voice, or were silent, expressed ambiguity in their non-verbal communication: and other team members took over the leader's tasks. In teams where the leader had control over the inner circle, the members seemed to have an awareness of each other's roles and tasks, knowing when in time and where in space these tasks needed to be executed. Deviations in the leaders' communication increased the ambiguity in the communication, which had consequences for the teamwork. Communication cannot be taken for granted; it needs to be practiced
Price of shifting the Hubble constant
Evslin, Jarah; Sen, Anjan A.; Ruchika
2018-05-01
An anisotropic measurement of the baryon acoustic oscillation (BAO) feature fixes the product of the Hubble constant and the acoustic scale H0rd. Therefore, regardless of the dark energy dynamics, to accommodate a higher value of H0 one needs a lower rd and so necessarily a modification of early time cosmology. One must either reduce the age of the Universe at the drag epoch or else the speed of sound in the primordial plasma. The first can be achieved, for example, with dark radiation or very early dark energy, automatically preserving the angular size of the acoustic scale in the cosmic microwave background (CMB) with no modifications to post-recombination dark energy. However, it is known that the simplest such modifications fall afoul of CMB constraints at higher multipoles. As an example, we combine anisotropic BAO with geometric measurements from strong lensing time delays from H0LiCOW and megamasers from the Megamaser Cosmology Project to measure rd, with and without the local distance ladder measurement of H0. We find that the best fit value of rd is indeed quite insensitive to the dark energy model and is also hardly affected by the inclusion of the local distance ladder data.
H0, q0 and the local velocity field. [Hubble and deceleration constants in Big Bang expansion
Sandage, A.; Tammann, G. A.
1982-01-01
An attempt is made to find a systematic deviation from linearity for distances that are under the control of the Virgo cluster, and to determine the value of the mean random motion about the systematic flow, in order to improve the measurement of the Hubble and the deceleration constants. The velocity-distance relation for large and intermediate distances is studied, and type I supernovae are calibrated relatively as distance indicators and absolutely to obtain a new value for the Hubble constant. Methods of determining the deceleration constant are assessed, including determination from direct measurement, mean luminosity density, virgocentric motion, and the time scale test. The very local velocity field is investigated, and a solution is preferred with a random peculiar radial velocity of very nearby field galaxies of 90-100 km/s, and a Virgocentric motion of the local group of 220 km/s, leading to an underlying expansion rate of 55, in satisfactory agreement with the global value.
Shin, Yuhyung; Eom, Chanyoung
2014-01-01
Despite the growing body of research on creativity in team contexts, very few attempts have been made to explore the team-level antecedents and the mediating processes of team creative performance on the basis of a theoretical framework. To address this gap, drawing on Paulus and Dzindolet's (2008) group creativity model, this study proposed team…
Nieboer Anna P; Strating Mathilde MH
2009-01-01
Abstract Background Although some studies have used the Team Climate Inventory within teams working in health care settings, none of these included quality improvement teams. The aim of our study is to investigate the psychometric properties of the 14-item version of the Team Climate Inventory in healthcare quality improvement teams participating in a Dutch quality collaborative. Methods This study included quality improvement teams participating in the Care for Better improvement program for...
Gajendran, Ravi S; Joshi, Aparna
2012-11-01
For globally distributed teams charged with innovation, member contributions to the team are crucial for effective performance. Prior research, however, suggests that members of globally distributed teams often feel isolated and excluded from their team's activities and decisions. How can leaders of such teams foster member inclusion in team decisions? Drawing on leader-member exchange (LMX) theory, we propose that for distributed teams, LMX and communication frequency jointly shape member influence on team decisions. Findings from a test of our hypotheses using data from 40 globally distributed teams suggest that LMX can enhance member influence on team decisions when it is sustained through frequent leader-member communication. This joint effect is strengthened as team dispersion increases. At the team level, member influence on team decisions has a positive effect on team innovation. (c) 2012 APA, all rights reserved.
Rédli, Tomáš
2011-01-01
Title of thesis: Comparison of indicators of the team game performance between the U.S. team and teams of his rivals at the Wprld Championship Men 2010 Aim of the thesis: The aim of the thesis is to compare indicators of the team game performance of Team USA and its rivals. On the basis of this comparison will be a confrontation of both teams after the match and find differences in their game performance. Methods of the thesis: The main method of the thesis is quantitative analysis of 6 selec...
Honor among thieves: The interaction of team and member deviance on trust in the team.
Schabram, Kira; Robinson, Sandra L; Cruz, Kevin S
2018-05-03
In this article, we examine member trust in deviant teams. We contend that a member's trust in his or her deviant team depends on the member's own deviant actions; although all members will judge the actions of their deviant teams as rational evidence that they should not be trusted, deviant members, but not honest members, can hold on to trust in their teams because of a sense of connection to the team. We tested our predictions in a field study of 562 members across 111 teams and 24 organizations as well as in an experiment of 178 participants in deviant and non-deviant teams. Both studies show that honest members experience a greater decline in trust as team deviance goes up. Moreover, our experiment finds that deviant members have as much trust in their deviant teams as honest members do in honest teams, but only in teams with coordinated rather than independent acts of deviance, in which deviant members engage in a variety of ongoing dynamics foundational to a sense of connection and affective-based trust. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Tinkering self-efficacy and team interaction on freshman engineering design teams
Richardson, Arlisa Labrie
This study utilizes Bandura's theory of self-efficacy as a framework to examine the development of tinkering skills white working on a freshman engineering design team. The four sources of self-efficacy were analyzed in the context of tinkering within the design team. The research question, 'Does tinkering self-efficacy change for female students during the Freshman Engineering Design class while working on mixed sex teams?', was addressed using quantitative data collection and field observations. Approximately 41 students enrolled in a freshman engineering design class at a public university in the southwest participated by providing self-reports about their tinkering involvement during each design project. In addition, three mixed-sex student teams were observed while working to complete the course design projects. An observation protocol based on Bandura's sources of self efficacy, was used to document tinkering interactions within the three observed teams. The results revealed that Bandura's sources of self-efficacy influenced tinkering involvement. The self-efficacy source, performance accomplishment measured through prior tinkering experience, was the most influential on tinkering involvement. Unlike Bandura's ranking of influence, verbal persuasion was shown to correlate with more tinkering behaviors than the observation of others. The number of females on a team had no impact on tinkering involvement. Tinkering involvement did not change as students progressed from one project to another. However, the competitive nature of the design project appeared to have a negative impact on tinkering involvement and the division of tasks within the team. In addition, a difference was found in the female students' perception of their tinkering involvement and observation of their tinkering involvement. The findings suggest that effective implementation of teamwork including teamwork preparation, more emphasis on the design process and the elimination of competition
Building multidisciplinary business teams
International Nuclear Information System (INIS)
Dyson, C.J.; Winte, N.C.
1991-01-01
This paper is a description of an approach to managing Exploration and Production assets through the operation of multidisciplinary business teams. The business team approach can assist in improved asset performance in terms of efficiency, motivation and business results, compared with more traditional matrix style hierarchies. Within this paper certain critical success factors for the long term success of multidiscipline teams are outlined, together with some of the risk of business team operation
Formalization of Team Creation
Cerman, Tomáš
2010-01-01
This paper is divided to practical and theoretical part. Theoretical part defines essential background of personality and work psychology which are pillars for using the personality and roles typology in practical part. I also define conceptions such as group, team, procedures of making the team. Practical part is focused at making the repertoary grid which outlines proximity of team roles, anchored in the repertoary grids upon personal atributes basis and picked team positions.
Hubble evolution of fireball in relativistic nuclear collisions
International Nuclear Information System (INIS)
Zgura, Sorin; Besliu, Calin; Jipa, Alexandru
2004-01-01
The final state of Au + Au collisions at √s = 130 A GeV and 200 A GeV at RHIC has been reconstructed within the framework of the Buda-Lund hydro model, by performing a simultaneous fit to preliminary BRAHMS, PHENIX, PHOBOS and STAR data on two-particle Bose-Einstein correlations and identified single particle spectra. The Hubble constant is determined for cosmology. From this reconstructed final state and the knowledge of the equation of state of hot and dense hadronic matter (e.g. from lattice QCD calculations) one can, in principle, reconstruct the initial state of the reaction by running the (relativistic) hydrodynamical equations backwards in time and determine if this initial state had been in the QGP phase or not. Here we report on such a reconstruction within the framework of the Buda-Lund hydro model. This model fits are compared to RHIC's experiment data on identified particle spectra, two-particle Bose-Einstein or HBT correlations. (authors)
The Hubble Space Telescope from concept to success
Shayler, David J
2016-01-01
The highly successful Hubble Space Telescope was meant to change our view and understanding of the universe. Within weeks of its launch in 1990, however, the space community was shocked to find out that the primary mirror of the telescope was flawed. It was only the skills of scientists and engineers on the ground and the daring talents of astronauts sent to service the telescope in December 1993 that saved the mission. For over two decades NASA had developed the capabilities to service a payload in orbit. This involved numerous studies and the creation of a ground-based infrastructure to support the challenging missions. Unique tools and EVA hardware supported the skills developed in crew training that then enabled astronauts to complete a demanding series of spacewalks. Drawing upon first hand interviews with those closely involved in the project over thirty years ago this story explains the development of the servicing mission concept and the hurdles that had to be overcome to not only launch the telescope...
En atferdsfortolkning av team-effektivitet: med fagartikkel: Problemløsende strategi for team-atferd
Eriksen-Deinoff, Tina E. Svedenborg
2014-01-01
Master i læring i komplekse systemer The concept of team defines a group of people by design or by selection of behaviour in a collaborating working process. Overall, teams are supposed to perform with better outcome than individuals do. Scholars have voiced the need for more scientific research and documentation of how teams perform with higher efficiency and better effectiveness. Mainly, scholars measure team-effectiveness and team-efficiency with surveys, observer ratings or behavi...
Hu, Jia; Erdogan, Berrin; Jiang, Kaifeng; Bauer, Talya N; Liu, Songbo
2018-03-01
In this study, we identify leader humility, characterized by being open to admitting one's limitations, shortcomings, and mistakes, and showing appreciation and giving credit to followers, as a critical leader characteristic relevant for team creativity. Integrating the literatures on creativity and leadership, we explore the relationship between leader humility and team creativity, treating team psychological safety and team information sharing as mediators. Further, we hypothesize and examine team power distance as a moderator of the relationship. We tested our hypotheses using data gathered from 72 work teams and 354 individual members from 11 information and technology firms in China using a multiple-source, time-lagged research design. We found that the positive relationship between leader humility and team information sharing was significant and positive only within teams with a low power distance value. In addition, leader humility was negatively related to team psychological safety in teams with a high power distance value, whereas the relationship was positive yet nonsignificant in teams with low power distance. Furthermore, team information sharing and psychological safety were both significantly related to team creativity. We discuss theoretical and practical implications for leadership and work teams. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Task versus relationship conflict, team performance and team member satisfaction: a meta-analysis
de Dreu, C.K.W.; Weingart, L.R.
2003-01-01
This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, resultsrevealed strong and negative correlations between relationship conflict, team performance, and
Hu, Jia; Liden, Robert C
2011-07-01
Integrating theories of self-regulation with team and leadership literatures, this study investigated goal and process clarity and servant leadership as 3 antecedents of team potency and subsequent team effectiveness, operationalized as team performance and organizational citizenship behavior. Our sample of 304 employees represented 71 teams in 5 banks. Results showed that team-level goal and process clarity as well as team servant leadership served as 3 antecedents of team potency and subsequent team performance and team organizational citizenship behavior. Furthermore, we found that servant leadership moderated the relationships between both goal and process clarity and team potency, such that the positive relationships between both goal and process clarity and team potency were stronger in the presence of servant leadership.
Helping fluid teams work: A research agenda for effective team adaptation in healthcare.
Bedwell, Wendy L; Ramsay, P Scott; Salas, Eduardo
2012-12-01
Although membership changes within teams are a common practice, research into this phenomenon is relatively nascent (Summers et al.; Acad Manag J 55:314-338, 2012). The small literature base, however, does provide insight into skills required for effective adaptation. The purpose of this effort is to provide a brief research synopsis, leading to research hypotheses about medical team training. By generalizing previous scientific findings regarding skills required for effective membership adaptation in different kinds of teams, we posit mechanisms whereby teamwork training might also support adaptation among medical teams (Burke et al.; Qual & Saf Health Care 13:i96-i104, 2004 and Salas et al.; Theor Issues Ergon Sci 8:381-394, 2007). We provide an overview of the membership change literature. Drawing upon literature from both within and outside of the medical domain, we suggest a framework and research propositions to aid in research efforts designed to determine the best content for helping to create adaptable medical teams through team training efforts. For effective adaptation, we suggest ad hoc teams should be trained on generalizable teamwork skills, to share just "enough" and the "right" information, to engage in shared leadership, and to shift from explicit to implicit coordination. Our overarching goal was to present what is known from the general research literature on successful team adaptation to membership changes, and to propose a research agenda to evaluate whether findings generalize to member changes in medical teams.
Leadership for Distributed Teams
De Rooij, J.P.G.
2009-01-01
The aim of this dissertation was to study the little examined, yet important issue of leadership for distributed teams. Distributed teams are defined as: “teams of which members are geographically distributed and are therefore working predominantly via mediated communication means on an
Theoretical colours and isochrones for some Hubble Space Telescope colour systems
Edvardsson, B.; Bell, R. A.
1989-01-01
Synthetic spectra for effective temperatures of 4000-7250 K, logarithmic surface gravities typical of dwarfs and subgiants, and metallicities from solar values to 0.001 of the solar metallicity were used to derive a grid of synthetic surface brightness magnitudes for 21 of the Hubble Space Telescope Wide Field Camera (WFC) band passes. The absolute magnitudes of these 21 band passes are also obtained for a set of globular cluster isochrones with different helium abundances, metallicities, oxygen abundances, and ages. The usefulness and efficiency of different sets of broad and intermediate bandwidth WFC colors for determining ages and metallicities for globular clusters are evaluated.
Interpersonal team leadership skills.
Nelson, M
1995-05-01
To say that a team leader's job is a tough one is certainly not saying enough. It is up to the team leader to manage a group of people to be individuals but yet work as a team. The team leader must keep the peace and yet create a revolution with this group all at the same time. The good leader will require a lot of education, training, and tons of practical application to be a success. The good news, however, is that the team leader's job is a rewarding one, one that they'll always feel good about if they do it right. How many of us get the opportunity to take a group of wonderful, thinking individual minds and pull from them ideas that a whole team can take to success? Yes, the job is indeed tough, but the paybacks are many.
The role of justice in team member satisfaction with the leader and attachment to the team.
Phillips, J M; Douthitt, E A; Hyland, M M
2001-04-01
This study examined the effects of team decision accuracy, team member decision influence, leader consideration behaviors, and justice perceptions on staff members' satisfaction with the leader and attachment to the team in hierarchical decision-making teams. The authors proposed that staff members' justice perceptions would mediate the relationship between (a) team decision accuracy, (b) the amount of influence a staff member has in the team leader's decision, and (c) the leader's consideration behaviors and staff attachment to the team and satisfaction with the leader. The results of an experiment involving 128 participants in a total of 64 teams, who made recommendations to a confederate acting as the team leader, generally support the proposed model.
van der Heijden, Beatrice; Verbaan, W.H.
2006-01-01
The aim of the study that is described in this article was to determine the relationship between team leaders' motivational behavior and the performance of their team members. Moreover, the differences between the team leaders' self-assessments of their motivational behavior and their team members'
Cultural Diversity and Team Performance
DEFF Research Database (Denmark)
Hoogendoorn, Sander; Van Praag, Mirjam
One of the most salient and relevant dimensions of team heterogeneity is cultural background. We measure the impact of cultural diversity on the performance of business teams using a field experiment. Companies are set up by teams of undergraduate students in business studies in realistic though...... similar circumstances. We vary the cultural composition of otherwise randomly composed teams in a multi-cultural student population. Our data indicate that a moderate level of cultural diversity has no effect on team performance in terms of business outcomes (sales, profits and profits per share). However......, if at least the majority of team members is culturally diverse then more cultural diversity seems to affect the performance of teams positively. Our data suggest that this might be related to the more diverse pool of relevant knowledge facilitating (mutual) learning within culturally diverse teams....
International Nuclear Information System (INIS)
Coe, R.P.; Carl, D.R.
1991-01-01
Numerous reports and articles have been written recently on the importance of team skills training for nuclear reactor operators, but little has appeared on the practical application of this theoretical guidance. This paper describes the activities of the Training and Education Department at GPU Nuclear (GPUN). In 1987, GPUN undertook a significant initiative in its licensed operator training programs to design and develop initial and requalification team skills training. Prior to that time, human interaction skills training (communication, stress management, supervisory skills, etc.) focused more on the individual rather than a group. Today, GPU Nuclear conducts team training at both its Three Mile Island (YMI), PA and Oyster Creek (OC), NJ generating stations. Videotaped feedback is sued extensively to critique and reinforce targeted behaviors. In fact, the TMI simulator trainer has a built-in, four camera system specifically designed for team training. Evaluations conducted on this training indicated these newly acquired skills are being carried over to the work environment. Team training is now an important and on-going part of GPUN operator training
Me, Myself, My Team How to be an effective team player using NLP
McLeod, Angus
2006-01-01
Me, Myself, My Team brings you effective strategies to improve your team's communication and motivation, discover new perceptions and begin new courses of action. Full of practical ideas, this exceptional book demonstrates how team playing achieves the best results.
2017-10-01
provision of training is not a major focus of this project, trainees were able to practice trauma management skills as well as leadership skills...SUBJECT TERMS Military healthcare team; Trauma teams; Team training; Teamwork; Adaptive performance; Leadership ; Simulation; Modeling; Bayesian belief...ABBREVIATIONS Healthcare team Trauma Trauma teams Team training Teamwork Adaptability Adaptive performance Leadership Simulation Modeling
Strasser, D C; Falconer, J A; Martino-Saltzmann, D
1994-02-01
Although inpatient rehabilitation is an interdisciplinary activity organized around a treatment team, there is a limited understanding of the workings of the interdisciplinary process. To elucidate staff perceptions of key aspects of the rehabilitation treatment process, we surveyed staff (n = 113) from selected inpatient teams. The staff completed social psychological instruments that measure perceptions of the hospital environment (The Ward Atmosphere Scale [WAS]), the team's environment (the Group Environment Scale [GES]), and interprofessional relations (Interprofessional Perception Scale [IPS]). Rehabilitation staff generally endorse the team approach, but express concerns over professional boundaries. Interprofessional difficulties seemed to be independent of team membership or professional training. Compared with published data from other settings, rehabilitation teams resembled task-oriented groups, but showed significant differences across teams in their perceptions of the team and hospital environments. The task-oriented character of rehabilitation teams, team-specific characteristics, and discord in interprofessional relationships may need to be considered in studies of rehabilitation teams effectiveness.
Facilitating Team Cognition : How designers mirror what NPD teams do
Stompff, G.
2012-01-01
Products are developed by large multi-disciplinary teams. The teams deal with many topics requiring the expertise of several specialists simultaneously. They have to decide together if something is a problem; propose multi-disciplinary solutions; and align their activities into a seamless whole.
Fostering teachers' team learning
Bouwmans, Machiel; Runhaar, Piety; Wesselink, Renate; Mulder, Martin
2017-01-01
The implementation of educational innovations by teachers seems to benefit from a team approach and team learning. The study's goal is to examine to what extent transformational leadership is associated with team learning, and to investigate the mediating roles of participative decision-making,
DEFF Research Database (Denmark)
Goldschmidt, P.; Oliver, S.J.; Serjeant, S.B.G.
1997-01-01
We present positions and fluxes of point sources found in the Infrared Space Observatory (ISO) images of the Hubble Deep Field (HDF) at 6.7 and 15 mu m. We have constructed algorithmically selected 'complete' flux-limited samples of 19 sources in the 15-mu m image, and seven sources in the 6.7-mu m...
Leader evaluation and team cohesiveness in the process of team development: A matter of gender?
Directory of Open Access Journals (Sweden)
Núria Rovira-Asenjo
Full Text Available Leadership positions are still stereotyped as masculine, especially in male-dominated fields (e.g., engineering. So how do gender stereotypes affect the evaluation of leaders and team cohesiveness in the process of team development? In our study participants worked in 45 small teams (4-5 members. Each team was headed by either a female or male leader, so that 45 leaders (33% women supervised 258 team members (39% women. Over a period of nine months, the teams developed specific engineering projects as part of their professional undergraduate training. We examined leaders' self-evaluation, their evaluation by team members, and team cohesiveness at two points of time (month three and month nine, the final month of the collaboration. While we did not find any gender differences in leaders' self-evaluation at the beginning, female leaders evaluated themselves more favorably than men at the end of the projects. Moreover, female leaders were evaluated more favorably than male leaders at the beginning of the project, but the evaluation by team members did not differ at the end of the projects. Finally, we found a tendency for female leaders to build more cohesive teams than male leaders.
Leader evaluation and team cohesiveness in the process of team development: A matter of gender?
Sczesny, Sabine; Gumí, Tània; Guimerà, Roger; Sales-Pardo, Marta
2017-01-01
Leadership positions are still stereotyped as masculine, especially in male-dominated fields (e.g., engineering). So how do gender stereotypes affect the evaluation of leaders and team cohesiveness in the process of team development? In our study participants worked in 45 small teams (4–5 members). Each team was headed by either a female or male leader, so that 45 leaders (33% women) supervised 258 team members (39% women). Over a period of nine months, the teams developed specific engineering projects as part of their professional undergraduate training. We examined leaders’ self-evaluation, their evaluation by team members, and team cohesiveness at two points of time (month three and month nine, the final month of the collaboration). While we did not find any gender differences in leaders’ self-evaluation at the beginning, female leaders evaluated themselves more favorably than men at the end of the projects. Moreover, female leaders were evaluated more favorably than male leaders at the beginning of the project, but the evaluation by team members did not differ at the end of the projects. Finally, we found a tendency for female leaders to build more cohesive teams than male leaders. PMID:29059231
Effects of team tenure and leadership in self-managing teams
Stoker, J.I.
2008-01-01
Purpose - This study seeks to identify the relationship between leader behaviour and the effectiveness of the members of a self-managing team (SMT) in terms of perceived individual performance and emotional exhaustion. In particular, it aims to examine the moderating role of individual team tenure.
The impact of team and work characteristics on team functioning
Molleman, E.; Slomp, J.
2006-01-01
In this article, the authors seek to strengthen the theoretical foundation of team and cell formation through the inclusion of human factors. They distinguish three types of team characteristics: global, shared, and compositional attributes. In this last category, they also deal with diversity in
Streefkerk, J.W.; Wiering, C.; Esch van-Bussemakers, M.; Neerincx, M.
2008-01-01
Team awareness is important when asking team members for assistance, for example in the police domain. This paper investigates how presentation modality (visual or auditory) of relevant team information and communication influences team awareness and choice accuracy in a collaborative team task. An
Directory of Open Access Journals (Sweden)
Lukman Setiawan
2017-08-01
Full Text Available This research aimed to: (1 analyze the influence of emotional intellegence to performance team at Undata Hospital, (2 to analyze the influence of Knowledge Sharing to the performance team at Undata Hospital, (3 to analyze the influence of team conflict to the team Performance at Undata Hospital, (4 to analyze the influence of emotional intellegence, Knowledge Sharing and team Conflict to the team Performance at Undata Hospital, (5 to know the dominant variable affecting the performance team at Undata Hospital. This study uses primary data through survey as many as 31 employees of the leadership element as a sample, the survey conducted for 2 (two months of May s.d July 2017. Data were analyzed using the program SPSS.22 The results showed that: (1 Emotional Intelligence and knowledge sharing have positive and significant influence on performance team at Undata Hospital, (2 Emotional Intellegence dominant influence to performance team at Undata Hospital. This means that emotional intellegence, knowledge sharing and team conflict can improve team performance at Undata Hospital with scientific facts found in this study indicate that emotional intellegence is the dominant variable of influence on team performance at Undata Hospital
International Nuclear Information System (INIS)
Cheney, G.T.
1992-01-01
This paper will address the purpose, scope, and approach of the Department of Energy Tiger Team Assessments. It will use the Tiger Team Assessment experience of Sandia National Laboratories at Albuquerque, New Mexico, as illustration
Hubble Space Telescope Wide Field Planetary Camera 2 Observations of Neptune
1995-01-01
Two groups have recently used the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC 2) to acquire new high-resolution images of the planet Neptune. Members of the WFPC-2 Science Team, lead by John Trauger, acquired the first series of images on 27 through 29 June 1994. These were the highest resolution images of Neptune taken since the Voyager-2 flyby in August of 1989. A more comprehensive program is currently being conducted by Heidi Hammel and Wes Lockwood. These two sets of observations are providing a wealth of new information about the structure, composition, and meteorology of this distant planet's atmosphere.Neptune is currently the most distant planet from the sun, with an orbital radius of 4.5 billion kilometers (2.8 billion miles, or 30 Astronomical Units). Even though its diameter is about four times that of the Earth (49,420 vs. 12,742 km), ground-based telescopes reveal a tiny blue disk that subtends less than 1/1200 of a degree (2.3 arc-seconds). Neptune has therefore been a particularly challenging object to study from the ground because its disk is badly blurred by the Earth's atmosphere. In spite of this, ground-based astronomers had learned a great deal about this planet since its position was first predicted by John C. Adams and Urbain Leverrier in 1845. For example, they had determined that Neptune was composed primarily of hydrogen and helium gas, and that its blue color caused by the presence of trace amounts of the gas methane, which absorbs red light. They had also detected bright cloud features whose brightness changed with time, and tracked these clouds to infer a rotation period between 17 and 22 hours.When the Voyager-2 spacecraft flew past the Neptune in 1989, its instruments revealed a surprising array of meteorological phenomena, including strong winds, bright, high-altitude clouds, and two large dark spots attributed to long-lived giant storm systems. These bright clouds and dark spots were tracked as they moved
A MULTIWAVELENGTH STUDY OF TADPOLE GALAXIES IN THE HUBBLE ULTRA DEEP FIELD
International Nuclear Information System (INIS)
Straughn, Amber N.; Eufrasio, Rafael T.; Gardner, Jonathan P.; Voyer, Elysse N.; Mello, Duilia de; Soto, Emmaris; Petty, Sara; Kassin, Susan; Ravindranath, Swara
2015-01-01
Multiwavelength data are essential in order to provide a complete picture of galaxy evolution and to inform studies of galaxies’ morphological properties across cosmic time. Here we present the results of a multiwavelength investigation of the morphologies of “tadpole” galaxies at intermediate redshift (0.314 < z < 3.175) in the Hubble Ultra Deep Field. These galaxies were previously selected from deep Hubble Space Telescope (HST) F775W data based on their distinct asymmetric knot-plus-tail morphologies. Here we use deep Wide Field Camera 3 near-infrared imaging in addition to the HST optical data in order to study the rest-frame UV/optical morphologies of these galaxies across the redshift range 0.3 < z < 3.2. This study reveals that the majority of these galaxies do retain their general asymmetric morphology in the rest-frame optical over this redshift range, if not the distinct “tadpole” shape. The average stellar mass of tadpole galaxies is lower than that of field galaxies, with the effect being slightly greater at higher redshift within the errors. Estimated from spectral energy distribution fits, the average age of tadpole galaxies is younger than that of field galaxies in the lower-redshift bin, and the average metallicity is lower (whereas the specific star formation rate for tadpoles is roughly the same as field galaxies across the redshift range probed here). These average effects combined support the conclusion that this subset of galaxies is in an active phase of assembly, either late-stage merging or cold gas accretion causing localized clumpy star formation
A MULTIWAVELENGTH STUDY OF TADPOLE GALAXIES IN THE HUBBLE ULTRA DEEP FIELD
Energy Technology Data Exchange (ETDEWEB)
Straughn, Amber N.; Eufrasio, Rafael T.; Gardner, Jonathan P. [Astrophysics Science Division, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States); Voyer, Elysse N. [Randstad at Google, 1129 San Antonio Road, Palo Alto, CA (United States); Mello, Duilia de; Soto, Emmaris [Department of Physics, The Catholic University of America, Washington, DC 20064 (United States); Petty, Sara [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Kassin, Susan; Ravindranath, Swara [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
2015-12-01
Multiwavelength data are essential in order to provide a complete picture of galaxy evolution and to inform studies of galaxies’ morphological properties across cosmic time. Here we present the results of a multiwavelength investigation of the morphologies of “tadpole” galaxies at intermediate redshift (0.314 < z < 3.175) in the Hubble Ultra Deep Field. These galaxies were previously selected from deep Hubble Space Telescope (HST) F775W data based on their distinct asymmetric knot-plus-tail morphologies. Here we use deep Wide Field Camera 3 near-infrared imaging in addition to the HST optical data in order to study the rest-frame UV/optical morphologies of these galaxies across the redshift range 0.3 < z < 3.2. This study reveals that the majority of these galaxies do retain their general asymmetric morphology in the rest-frame optical over this redshift range, if not the distinct “tadpole” shape. The average stellar mass of tadpole galaxies is lower than that of field galaxies, with the effect being slightly greater at higher redshift within the errors. Estimated from spectral energy distribution fits, the average age of tadpole galaxies is younger than that of field galaxies in the lower-redshift bin, and the average metallicity is lower (whereas the specific star formation rate for tadpoles is roughly the same as field galaxies across the redshift range probed here). These average effects combined support the conclusion that this subset of galaxies is in an active phase of assembly, either late-stage merging or cold gas accretion causing localized clumpy star formation.
Structuring Effective Student Teams.
Dickson, Ellen L.
1997-01-01
Experience with student teams working on policy analysis projects indicates the need for faculty supervision of teams in the process of addressing complex issues. The problem-solving approach adopted in one policy analysis course is described, including assignments and tasks, issues and sponsors, team dynamics, conflict management, and the…
DEFF Research Database (Denmark)
Ma, Zheng; Lin, Chih-Cheng; Tanev, Stoyan
2012-01-01
elaborates on the role of culture diversity and geographical dispersion in NPD team conflict. A simulation is conducted where organizations may be regarded as complex systems to affect the team conflict with a variety of influences. The results firstly indicate that there are two dimensions of NPD team...... conflict: stable and unstable dimensions with four elements: task characteristics, group members’ relationship, cultural diversity and geographical dispersion; secondly, there are two phenomena whereby the geographical dispersion influences the NPD team interaction, and the influence between cultural...
Affirmative action and team performance
Kölle, Felix
2016-01-01
We experimentally investigate spillover effects of affirmative action policies in tournaments on subsequent team performance and the willingness to work in teams. In three different team environments, we find that such policies in form of gender quotas do not harm performance and cooperation within teams, and do not weaken people's willingness to work in teams. Our results, thus, provide further evidence that gender quotas can have the desired effect of promoting women without harming efficie...
Jasionis, Dominykas
2016-01-01
The term paper is to analyze the formation of the team and its - motyvation, and interviews from four different companies and find out the leaders in terms of your team, and what principle he tries to motivate her. The Tasks of this paper is to review the organization formed by a team; investigate the promotion of employees in enterprises; The four firms interviewed; Assess how you can work in different organizations. Methods used To analyze the topic, I decided to interview four different co...
A season-long team-building intervention: examining the effect of team goal setting on cohesion.
Senécal, Julie; Loughead, Todd M; Bloom, Gordon A
2008-04-01
The purpose of the current study was to determine whether the implementation of a season-long team-building intervention program using team goal setting increased perceptions of cohesion. The participants were 86 female high school basketball players from 8 teams. The teams were randomly assigned to either an experimental team goal-setting or control condition. Each participant completed the Group Environment Questionnaire (GEQ; Carron, Brawley, & Widmeyer, 2002; Carron, Widmeyer, & Brawley, 1985), which assessed cohesion at both the beginning and end of the season. Overall, the results revealed a significant multivariate effect, Pillai's trace F(12, 438) = 2.68, p = .002. Post hoc analyses showed that at the beginning of the season, athletes from both conditions did not differ in their perceptions of cohesion. However, at the end of the season, athletes in the team goal-setting condition held higher perceptions of cohesion than athletes in the control condition. Overall, the results indicated that team goal setting was an effective team-building tool for influencing cohesiveness in sport teams.
Directory of Open Access Journals (Sweden)
Sean Cordes
2016-12-01
Full Text Available The study examines two dimensions that impact virtual team decision making. One is the influence of collaboration process structure: the sequences, patterns, and routines participants use to interact and solve problems. The other is technology affordance: the strengths and weaknesses of technologies in terms of the usefulness they offer to teams when performing tasks. Some teams used a structured collaboration process with monitoring, coordination, and backup functions during a decision-making discussion. Other teams had no discussion process instructions. In addition, some teams possessed stronger technology affordance including both chat and an editable document. Other teams used chat technology alone, which offered fewer collaboration possibilities. The collaboration process and technology affordance factors were tested in an experiment in which four-person online teams worked as a personnel hiring committee. Information about four job candidates was distributed to create a hidden profile in which some information was shared across all team members, while other information was visible only to specific members. Two hundred and eight students, comprising fifty-two teams completed the study. Teams using the structured collaboration process made more accurate and higher-quality decisions. In addition, scores were higher when technology affordance included both chat and editable document tools, but this influence was not significant.
Littlepage, Glenn E; Hein, Michael B; Moffett, Richard G; Craig, Paul A; Georgiou, Andrea M
2016-12-01
This study evaluates the effectiveness of a training program designed to improve cross-functional coordination in airline operations. Teamwork across professional specializations is essential for safe and efficient airline operations, but aviation education primarily emphasizes positional knowledge and skill. Although crew resource management training is commonly used to provide some degree of teamwork training, it is generally focused on specific specializations, and little training is provided in coordination across specializations. The current study describes and evaluates a multifaceted training program designed to enhance teamwork and team performance of cross-functional teams within a simulated airline flight operations center. The training included a variety of components: orientation training, position-specific declarative knowledge training, position-specific procedural knowledge training, a series of high-fidelity team simulations, and a series of after-action reviews. Following training, participants demonstrated more effective teamwork, development of transactive memory, and more effective team performance. Multifaceted team training that incorporates positional training and team interaction in complex realistic situations and followed by after-action reviews can facilitate teamwork and team performance. Team training programs, such as the one described here, have potential to improve the training of aviation professionals. These techniques can be applied to other contexts where multidisciplinary teams and multiteam systems work to perform highly interdependent activities. © 2016, Human Factors and Ergonomics Society.
DEFF Research Database (Denmark)
Bjørn, Pernille
technology in six real-life virtual teams, two in industry and four in education, applying interpretative research and action research methods. Two main lines of investigation are pursued: the first involves an examination of the organisational issues related to groupware adaptation in virtual project teams......, professional disciplines, time differences and technology. This thesis comprises a general introduction, referred to as the summary report, and seven research papers, which deal in detail with the results and findings of the empirical cases. The summary report provides a general introduction to the research......, while the second looks at the social context and practices of virtual project teams. Two of the key findings are 1) that the process of groupware adaptation by virtual project teams can be viewed as a process of expanding and aligning the technological frames of the participants, which includes mutual...
Mathisen, Gro Ellen; Martinsen, Oyvind; Einarsen, Stale
2008-01-01
This study investigates the relationship between creative personality composition, innovative team climate, and team innovation based on an input-process-output model. We measured personality with the Creative Person Profile, team climate with the Team Climate Inventory, and team innovation through team-member and supervisor reports of team…
Planetary nebulae: 20 years of Hubble inquiry
Balick, Bruce
2012-08-01
The Hubble Space Telescope has served the critical roles of microscope and movie camera in the past 20 years of research on planetary nebulae (``PNe''). We have glimpsed the details of the evolving structures of neutral and ionized post-AGB objects, built ingenious heuristic models that mimic these structures, and constrained most of the relevant physical processes with careful observations and interpretation. We have searched for close physical binary stars with spatial resolution ~50 AU at 1 AU, located jets emerging from the nucleus at speeds up to 2000 km s-1 and matched newly discovered molecular and X-ray emission regions to physical substructures in order to better understand how stellar winds and ionizing radiation interact to form the lovely symmetries that are observed. Ultraviolet spectra of CNO in PNe help to uncover how stars process deep inside AGB stars with unstable nuclear burning zones. HST broadband imaging has been at the forefront of uncovering surprisingly complex wind morphologies produced at the tip of the AGB, and has led to an increasing realization of the potentially vital roles of close binary stars and emerging magnetic fields in shaping stellar winds.
M.M.H. Strating (Mathilde); A.P. Nieboer (Anna)
2009-01-01
textabstractAbstract BACKGROUND: Although some studies have used the Team Climate Inventory within teams working in health care settings, none of these included quality improvement teams. The aim of our study is to investigate the psychometric properties of the 14-item version of the Team Climate
Team errors: definition and taxonomy
International Nuclear Information System (INIS)
Sasou, Kunihide; Reason, James
1999-01-01
In error analysis or error management, the focus is usually upon individuals who have made errors. In large complex systems, however, most people work in teams or groups. Considering this working environment, insufficient emphasis has been given to 'team errors'. This paper discusses the definition of team errors and its taxonomy. These notions are also applied to events that have occurred in the nuclear power industry, aviation industry and shipping industry. The paper also discusses the relations between team errors and Performance Shaping Factors (PSFs). As a result, the proposed definition and taxonomy are found to be useful in categorizing team errors. The analysis also reveals that deficiencies in communication, resource/task management, excessive authority gradient, excessive professional courtesy will cause team errors. Handling human errors as team errors provides an opportunity to reduce human errors
The Brightest of Reionizing Galaxies Survey: Design and Preliminary Results
Trenti, M.; Bradley, L. D.; Stiavelli, M.; Oesch, P.; Treu, T.; Bouwens, R. J.; Shull, J. M.; MacKenty, J. W.; Carollo, C. M.; Illingworth, G. D.
2011-02-01
We present the first results on the search for very bright (M AB ≈ -21) galaxies at redshift z ~ 8 from the Brightest of Reionizing Galaxies (BoRG) survey. BoRG is a Hubble Space Telescope Wide Field Camera 3 (WFC3) pure-parallel survey that is obtaining images on random lines of sight at high Galactic latitudes in four filters (F606W, F098M, F125W, and F160W), with integration times optimized to identify galaxies at z >~ 7.5 as F098M dropouts. We discuss here results from a search area of approximately 130 arcmin2 over 23 BoRG fields, complemented by six other pure-parallel WFC3 fields with similar filters. This new search area is more than two times wider than previous WFC3 observations at z ~ 8. We identify four F098M-dropout candidates with high statistical confidence (detected at greater than 8σ confidence in F125W). These sources are among the brightest candidates currently known at z ~ 8 and approximately 10 times brighter than the z = 8.56 galaxy UDFy-38135539. They thus represent ideal targets for spectroscopic follow-up observations and could potentially lead to a redshift record, as our color selection includes objects up to z ~ 9. However, the expected contamination rate of our sample is about 30% higher than typical searches for dropout galaxies in legacy fields, such as the GOODS and HUDF, where deeper data and additional optical filters are available to reject contaminants. Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with Programs 11700, 11702.
Establishment of self-governing teams
DEFF Research Database (Denmark)
Voxted, Søren
Paperet har til formål at diskutere former for deltaglse og autonomi ved forkellige typer af teams både som team og for teamets enkeldeltagere......Paperet har til formål at diskutere former for deltaglse og autonomi ved forkellige typer af teams både som team og for teamets enkeldeltagere...
Predictors of Team Work Satisfaction
Hamlyn-Harris, James H.; Hurst, Barbara J.; von Baggo, Karola; Bayley, Anthony J.
2006-01-01
The ability to work in teams is an attribute highly valued by employers of information technology (IT) graduates. For IT students to effectively engage in team work tasks, the process of working in teams should be satisfying for the students. This work explored whether university students who were involved in compulsory team work were satisfied…
Burtscher, Michael J.; Kolbe, Michaela; Wacker, Johannes; Manser, Tanja
2011-01-01
In the present study, we investigated how two team mental model properties (similarity vs. accuracy) and two forms of monitoring behavior (team vs. systems) interacted to predict team performance in anesthesia. In particular, we were interested in whether the relationship between monitoring behavior and team performance was moderated by team…
Monaghan, Conal; Bizumic, Boris; Reynolds, Katherine; Smithson, Michael; Johns-Boast, Lynette; van Rooy, Dirk
2015-01-01
One prominent approach in the exploration of the variations in project team performance has been to study two components of the aggregate personalities of the team members: conscientiousness and agreeableness. A second line of research, known as self-categorisation theory, argues that identifying as team members and the team's performance norms…
Leadership by Confidence in Teams
Kobayashi, Hajime; Suehiro, Hideo
2008-01-01
We study endogenous signaling by analyzing a team production problem with endogenous timing. Each agent of the team is privately endowed with some level of confidence about team productivity. Each of them must then commit a level of effort in one of two periods. At the end of each period, each agent observes his partner' s move in this period. Both agents are rewarded by a team output determined by team productivity and total invested effort. Each agent must personally incur the cost of effor...
THE 2012 HUBBLE ULTRA DEEP FIELD (UDF12): OBSERVATIONAL OVERVIEW
Energy Technology Data Exchange (ETDEWEB)
Koekemoer, Anton M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Ellis, Richard S.; Schenker, Matthew A. [Department of Astrophysics, California Institute of Technology, MS 249-17, Pasadena, CA 91125 (United States); McLure, Ross J.; Dunlop, James S.; Bowler, Rebecca A. A.; Rogers, Alexander B.; Curtis-Lake, Emma; Cirasuolo, Michele; Wild, V.; Targett, T. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh EH9 3HJ (United Kingdom); Robertson, Brant E.; Schneider, Evan; Stark, Daniel P. [Department of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Ono, Yoshiaki; Ouchi, Masami [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa City, Chiba 277-8582 (Japan); Charlot, Stephane [UPMC-CNRS, UMR7095, Institut d' Astrophysique de Paris, F-75014, Paris (France); Furlanetto, Steven R. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)
2013-11-01
We present the 2012 Hubble Ultra Deep Field campaign (UDF12), a large 128 orbit Cycle 19 Hubble Space Telescope program aimed at extending previous Wide Field Camera 3 (WFC3)/IR observations of the UDF by quadrupling the exposure time in the F105W filter, imaging in an additional F140W filter, and extending the F160W exposure time by 50%, as well as adding an extremely deep parallel field with the Advanced Camera for Surveys (ACS) in the F814W filter with a total exposure time of 128 orbits. The principal scientific goal of this project is to determine whether galaxies reionized the universe; our observations are designed to provide a robust determination of the star formation density at z ∼> 8, improve measurements of the ultraviolet continuum slope at z ∼ 7-8, facilitate the construction of new samples of z ∼ 9-10 candidates, and enable the detection of sources up to z ∼ 12. For this project we committed to combining these and other WFC3/IR imaging observations of the UDF area into a single homogeneous dataset to provide the deepest near-infrared observations of the sky. In this paper we present the observational overview of the project and describe the procedures used in reducing the data as well as the final products that were produced. We present the details of several special procedures that we implemented to correct calibration issues in the data for both the WFC3/IR observations of the main UDF field and our deep 128 orbit ACS/WFC F814W parallel field image, including treatment for persistence, correction for time-variable sky backgrounds, and astrometric alignment to an accuracy of a few milliarcseconds. We release the full, combined mosaics comprising a single, unified set of mosaics of the UDF, providing the deepest near-infrared blank-field view of the universe currently achievable, reaching magnitudes as deep as AB ∼ 30 mag in the near-infrared, and yielding a legacy dataset on this field.
THE 2012 HUBBLE ULTRA DEEP FIELD (UDF12): OBSERVATIONAL OVERVIEW
International Nuclear Information System (INIS)
Koekemoer, Anton M.; Ellis, Richard S.; Schenker, Matthew A.; McLure, Ross J.; Dunlop, James S.; Bowler, Rebecca A. A.; Rogers, Alexander B.; Curtis-Lake, Emma; Cirasuolo, Michele; Wild, V.; Targett, T.; Robertson, Brant E.; Schneider, Evan; Stark, Daniel P.; Ono, Yoshiaki; Ouchi, Masami; Charlot, Stephane; Furlanetto, Steven R.
2013-01-01
We present the 2012 Hubble Ultra Deep Field campaign (UDF12), a large 128 orbit Cycle 19 Hubble Space Telescope program aimed at extending previous Wide Field Camera 3 (WFC3)/IR observations of the UDF by quadrupling the exposure time in the F105W filter, imaging in an additional F140W filter, and extending the F160W exposure time by 50%, as well as adding an extremely deep parallel field with the Advanced Camera for Surveys (ACS) in the F814W filter with a total exposure time of 128 orbits. The principal scientific goal of this project is to determine whether galaxies reionized the universe; our observations are designed to provide a robust determination of the star formation density at z ∼> 8, improve measurements of the ultraviolet continuum slope at z ∼ 7-8, facilitate the construction of new samples of z ∼ 9-10 candidates, and enable the detection of sources up to z ∼ 12. For this project we committed to combining these and other WFC3/IR imaging observations of the UDF area into a single homogeneous dataset to provide the deepest near-infrared observations of the sky. In this paper we present the observational overview of the project and describe the procedures used in reducing the data as well as the final products that were produced. We present the details of several special procedures that we implemented to correct calibration issues in the data for both the WFC3/IR observations of the main UDF field and our deep 128 orbit ACS/WFC F814W parallel field image, including treatment for persistence, correction for time-variable sky backgrounds, and astrometric alignment to an accuracy of a few milliarcseconds. We release the full, combined mosaics comprising a single, unified set of mosaics of the UDF, providing the deepest near-infrared blank-field view of the universe currently achievable, reaching magnitudes as deep as AB ∼ 30 mag in the near-infrared, and yielding a legacy dataset on this field
Bornay-Barrachina, Mar; Herrero, Inés
2018-01-01
The purpose of this study was to investigate how high-quality dyadic co-worker relationships (CWXs) favour or hinder team performance. Specifically, we examine the role played by CWX, team creative environment, job complexity and task interdependence to achieve higher levels of team performance. We analyse data from 410 individuals belonging to 81 R&D teams in technology sciences to examine the quality of the dyadic relationships between team members under the same supervisor (co-workers) and team performance measured by the number of publications as their research output. Higher levels of team average CWX relationships are positively related to the establishment of a favourable creative team environment, ending into higher levels of team performance. Specifically, the role played by team average CWX in such relationship is stronger when job complexity and task interdependence are also high. Team's output not only depends on the leader and his/her relationships with subordinates but also on quality relationships among team members. CWXs contribute to creative team environments, but they are essential where jobs are complex and tasks are highly dependent. This study provides evidence of the important role played by CWXs in determining a creative environment, irrespective of their leaders. Previous research has provided information about how leader's role affects team outcomes, but the role of dyadic co-worker relationships in a team remains still relatively unknown. Considering job complexity and task interdependence variables, the study provides with a better understanding about how and when high-quality CWXs should be promoted to achieve higher team performance.
Leadership for Team Learning: The Case of University Teacher Teams
Koeslag-Kreunen, Mieke G. M.; Van der Klink, Marcel R.; Van den Bossche, Piet; Gijselaers, Wim H.
2018-01-01
Teacher team involvement is considered a key factor in achieving sustainable innovation in higher education. This requires engaging in team learning behaviors that should result in new knowledge and solutions. However, university teachers are not used to discussing their work practices with one another and tend to neglect any innovation in their…
Experimental evaluation of the influence of the team members' personalities on the team performance
International Nuclear Information System (INIS)
Nagasaka, Akihiko
1998-01-01
This report deals with the result of the experiment that testees' teams had coped with abnormal events on power plant simulator. 8 teams were AAA1, AAA2, ACD1, ACD2, CCC1, CCC2, DDD1 and DDD2 consist of 3 members. Members of teams were intentionally united by his personality with the results examined by Yatabe-Guilford personality test (A: Average type, C: Calm type, D: Director type). Each team coped with 8 abnormal events (leak from the pipe after the condensate booster pump-A and feedwater control system failure, vacuum pump-A failure, etc.). Teams' behaviors were evaluated and calculated the evaluated values about 3 team's functions: (1) direction and orientation (11 items), (2) recovery (13 items) and (3) maintenance of cooperation (13 items). The order of the evaluated values were almost AAAs≤ACDs≤CCCs< DDDs with each function. And the results on multiple comparison of the evaluated values are as follows: (a) There are remarkable significances between DDDs and other combinations of personalities (32 cases per 36 cases). (b) Some cases are significant among 2 teams of same combination of personalities (4 cases per 12 cases). Also the results on analysis of utterances of team member are as follows: (c) There is good correspondence of the number of utterances to the evaluated values. (d) With AAAs, the number of 'Instruction' is very small. (e) With CCCs, utterances related to maintenance of cooperation are relatively few. On these results, the author is convinced that combination of personalities in not matured team certainly relates team performance and utterances among the members. (author)
An examination of organizational and team commitment in a self-directed team environment.
Bishop, James W; Scott, K Dow
2000-06-01
A model hypothesizing differential relationships among predictor variables and individual commitment to the organization and work team was tested. Data from 485 members of sewing teams supported the existence of differential relationships between predictors and organizational and team commitment. In particular, intersender conflict and satisfaction with coworkers were more strongly related to team commitment than to organizational commitment. Resource-related conflict and satisfaction with supervision were more strongly related to organizational commitment than to team commitment. Perceived task interdependence was strongly related to both commitment foci. Contrary to prediction, the relationships between perceived task interdependence and the 2 commitment foci were not significantly different. Relationships with antecedent variables help explain how differential levels of commitment to the 2 foci may be formed. Indirect effects of exogenous variables are reported.
A natural language query system for Hubble Space Telescope proposal selection
Hornick, Thomas; Cohen, William; Miller, Glenn
1987-01-01
The proposal selection process for the Hubble Space Telescope is assisted by a robust and easy to use query program (TACOS). The system parses an English subset language sentence regardless of the order of the keyword phases, allowing the user a greater flexibility than a standard command query language. Capabilities for macro and procedure definition are also integrated. The system was designed for flexibility in both use and maintenance. In addition, TACOS can be applied to any knowledge domain that can be expressed in terms of a single reaction. The system was implemented mostly in Common LISP. The TACOS design is described in detail, with particular attention given to the implementation methods of sentence processing.
International Nuclear Information System (INIS)
Turner, E.L.
1979-01-01
A rank statistic version of the magnitude-redshift q 0 test is developed. It may be applied to the Hubble diagram of objects with an arbitrary and unknown luminosity function; in particular, the objects need not be ''standard candles.'' Only the single restriction that the objects' luminosity function does not vary in functional form is placed on the sources' intrinsic properties. Density and/or luminosity evolution are taken into account. Corrections for sample selection biases are incorporated into the analysis. Tests for the presence of luminosity evolution are given. Methods for determining either q 0 or the luminosity evolution when the other is a priori known are described.Application of these techniques to a sample of 119 3CR and 4C quasars leads to the following results: The radio Hubble diagram is consistent with all values of q 0 , suggesting that the quasar radio luminosity function is a featureless power law. The optical Hubble diagram indicates one of these possibilities: (1) the value of q 0 is in the range 2--32, probably near 5; (2) the value of q 0 is more reasonable and there is strong optical luminosity evolution [e.g., if q/sub o/ approx. = 0.05, then the characteristic optical luminosity scales like approx. (1 + Z)/sup 7/3/]; or (3) the data are a low-probability (< or =0.05) statistical fluctuation. The second interpretation is probably the most sensible one.Generalizations of the rank statistic magnitude-redshift test are suggested for application to a variety of extragalactic and stellar problems. Specific examples of applications to unorthodox cosmologies are given. Even for the unfavorable (very broad luminosity function) case of the optical quasar data, the rank statistic analysis is sensitive to relative variations in the distance-modulus-redshift relation as small as approx.0.4 mag for 1/2 < or = Z < or = 2
Directory of Open Access Journals (Sweden)
Anton F. Schlechter
2008-06-01
Full Text Available This exploratory study tested a model within a team context consisting of transformational-leadership behaviour, team-leader emotional intelligence, trust (both in the team leader and in the team members and team commitment. It was conducted within six manufacturing plants, with 25 teams participating. Of the 320 surveys distributed to these teams, 178 were received (which equals a 56% response rate. The surveys consisted of the multi-factor leadership questionnaire (MLQ, the Swinburne University emotional intelligence test (SUEIT, the organisational-commitment scale (OCS (adapted for team commitment and the workplace trust survey (WTS. The validity of these scales was established using exploratory factor analysis (EFA and confrmatory factor analysis (CFA. The Cronbach alpha was used to assess the reliability of the scales. The model was tested using structural equation modelling (SEM; an acceptable level of model ft was found. Signifcant positive relationships were further found among all the constructs. Such an integrated model has not been tested in a team context before and the positive fndings therefore add to existing teamwork literature. The fnding that transformational leadership and leader emotional intelligence are positively related to team commitment and trust further emphasises the importance of effective leadership behaviour in team dynamics and performance.
Filho, Edson; Tenenbaum, Gershon; Yang, Yanyun
2015-01-01
A nomological network on team dynamics in sports consisting of a multiframework perspective is introduced and tested. The aim was to explore the interrelationship among cohesion, team mental models (TMMs), collective efficacy (CE) and perceived performance potential (PPP). Three hundred and forty college-aged soccer players representing 17 different teams (8 female and 9 male) participated in the study. They responded to surveys on team cohesion, TMMs, CE and PPP. Results are congruent with the theoretical conceptualisation of a parsimonious view of team dynamics in sports. Specifically, cohesion was found to be an exogenous variable predicting both TMMs and CE beliefs. TMMs and CE were correlated and predicted PPP, which in turn accounted for 59% of the variance of objective performance scores as measured by teams' season record. From a theoretical standpoint, findings resulted in a parsimonious view of team dynamics, which may represent an initial step towards clarifying the epistemological roots and nomological network of various team-level properties. From an applied standpoint, results suggest that team expertise starts with the establishment of team cohesion. Following the establishment of cohesiveness, teammates are able to advance team-related schemas and a collective sense of confidence. Limitations and key directions for future research are outlined.
Directory of Open Access Journals (Sweden)
Nieboer Anna P
2009-07-01
Full Text Available Abstract Background Although some studies have used the Team Climate Inventory within teams working in health care settings, none of these included quality improvement teams. The aim of our study is to investigate the psychometric properties of the 14-item version of the Team Climate Inventory in healthcare quality improvement teams participating in a Dutch quality collaborative. Methods This study included quality improvement teams participating in the Care for Better improvement program for home care, care for the handicapped and the elderly in the Netherlands between 2006 and 2008. As part of a larger evaluation study 270 written questionnaires from team members were collected at baseline and 139 questionnaires at end measurement. Confirmatory factor analyses, reliability, Pearson correlations and paired samples t-tests were conducted to investigate construct validity, reliability, predictive validity and temporal stability. Results Confirmatory factor analyses revealed the expected four-factor structure and good fit indices. For the four subscales – vision, participative safety, task orientation and support for innovation – acceptable Cronbach's alpha coefficients and high inter-item correlations were found. The four subscales all proved significant predictors of perceived team effectiveness, with participatory safety being the best predictor. As expected the four subscales were found to be stable over time; i.e. without significant changes between baseline and end measurement. Conclusion The psychometric properties of the Dutch version of the TCI-14 are satisfactory. Together these results show that the TCI-14 is a useful instrument to assess to what extent aspects of team climate influence perceived team effectiveness of quality improvement teams.
Strating, Mathilde M H; Nieboer, Anna P
2009-07-24
Although some studies have used the Team Climate Inventory within teams working in health care settings, none of these included quality improvement teams. The aim of our study is to investigate the psychometric properties of the 14-item version of the Team Climate Inventory in healthcare quality improvement teams participating in a Dutch quality collaborative. This study included quality improvement teams participating in the Care for Better improvement program for home care, care for the handicapped and the elderly in the Netherlands between 2006 and 2008. As part of a larger evaluation study 270 written questionnaires from team members were collected at baseline and 139 questionnaires at end measurement. Confirmatory factor analyses, reliability, Pearson correlations and paired samples t-tests were conducted to investigate construct validity, reliability, predictive validity and temporal stability. Confirmatory factor analyses revealed the expected four-factor structure and good fit indices. For the four subscales--vision, participative safety, task orientation and support for innovation--acceptable Cronbach's alpha coefficients and high inter-item correlations were found. The four subscales all proved significant predictors of perceived team effectiveness, with participatory safety being the best predictor. As expected the four subscales were found to be stable over time; i.e. without significant changes between baseline and end measurement. The psychometric properties of the Dutch version of the TCI-14 are satisfactory. Together these results show that the TCI-14 is a useful instrument to assess to what extent aspects of team climate influence perceived team effectiveness of quality improvement teams.
Fiorentino, G.; Ramos, R. Contreras; Clementini, G.; Marconi, M.; Musella, I.; Aloisi, A.; Annibali, F.; Saha, A.; Tosi, M.; van der Marel, R. P.
2010-01-01
Variable stars have been identified for the first time in the very metal-poor blue compact dwarf galaxy IZw18, using deep multi-band (F606W, F814W) time-series photometry obtained with the Advanced Camera for Surveys on board the Hubble Space Telescope. We detected 34 candidate variable stars in the
Fransen, Katrien; Haslam, S Alexander; Mallett, Clifford J; Steffens, Niklas K; Peters, Kim; Boen, Filip
2017-08-01
Researchers have argued that leadership is one of the most important determinants of team effectiveness. The present study examined the extent to which the perceived quality of athlete leadership was related to the effectiveness of elite sports teams. Three professional football teams (N=135) participated in our study during the preparation phase for the Australian 2016 season. Players and coaching staff were asked to assess players' leadership quality in four leadership roles (as task, motivational, social, and external leader) via an online survey. The leadership quality in each of these roles was then calculated in a social network analysis by averaging the indegree centralities of the three best leaders in that particular role. Participants also rated their team's performance and its functioning on multiple indicators. As hypothesized, the team with the highest-quality athlete leadership on each of the four leadership roles excelled in all indicators of team effectiveness. More specifically, athletes in this team had a stronger shared sense of the team's purpose, they were more highly committed to realizing the team's goals, and they had a greater confidence in their team's abilities than athletes in the other teams. Moreover, this team demonstrated a higher task-involving and a lower ego-involving climate, and excelled on all measures of performance. High-quality athlete leadership is positively related to team effectiveness. Given the importance of high-quality athlete leadership, the study highlights the need for well-designed empirically-based leadership development programs. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Panchromatic Hubble Andromeda Treasury. IX. A photometric survey of planetary nebulae in M31
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Veyette, Mark J.; Williams, Benjamin F.; Dalcanton, Julianne J.; Balick, Bruce; Fouesneau, Morgan [Department of Astronomy, University of Washington, P.O. Box 351580, Seattle, WA 98195 (United States); Caldwell, Nelson [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Girardi, Léo [Osservatorio Astronomico di Padova—INAF, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Gordon, Karl D.; Kalirai, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Rosenfield, Philip [Department of Physics and Astronomy G. Galilei, University of Padova, Vicolo dell' Osservatorio 3, I-35122 Padova (Italy); Seth, Anil C., E-mail: mveyette@uw.edu [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States)
2014-09-10
We search the Hubble Space Telescope (HST) Advanced Camera for Surveys and Wide Field Camera 3 broadband imaging data from the Panchromatic Hubble Andromeda Treasury (PHAT) survey to identify detections of cataloged planetary nebulae (PNs). Of the 711 PNs currently in the literature within the PHAT footprint, we find 467 detected in the broadband. For these 467, we are able to refine their astrometric accuracy from ∼0.''3 to 0.''05. Using the resolution of the HST, we are able to show that 152 objects currently in the catalogs are definitively not PNs, and we show that 32 objects thought to be extended in ground-based images are actually point-like and therefore good PN candidates. We also find one PN candidate that is marginally resolved. If this is a PN, it is up to 0.7 pc in diameter. With our new photometric data, we develop a method of measuring the level of excitation in individual PNs by comparing broadband and narrowband imaging and describe the effects of excitation on a PN's photometric signature. Using the photometric properties of the known PNs in the PHAT catalogs, we search for more PNs, but do not find any new candidates, suggesting that ground-based emission-line surveys are complete in the PHAT footprint to F475W ≅ 24.
Basketball teams as strategic networks.
Fewell, Jennifer H; Armbruster, Dieter; Ingraham, John; Petersen, Alexander; Waters, James S
2012-01-01
We asked how team dynamics can be captured in relation to function by considering games in the first round of the NBA 2010 play-offs as networks. Defining players as nodes and ball movements as links, we analyzed the network properties of degree centrality, clustering, entropy and flow centrality across teams and positions, to characterize the game from a network perspective and to determine whether we can assess differences in team offensive strategy by their network properties. The compiled network structure across teams reflected a fundamental attribute of basketball strategy. They primarily showed a centralized ball distribution pattern with the point guard in a leadership role. However, individual play-off teams showed variation in their relative involvement of other players/positions in ball distribution, reflected quantitatively by differences in clustering and degree centrality. We also characterized two potential alternate offensive strategies by associated variation in network structure: (1) whether teams consistently moved the ball towards their shooting specialists, measured as "uphill/downhill" flux, and (2) whether they distributed the ball in a way that reduced predictability, measured as team entropy. These network metrics quantified different aspects of team strategy, with no single metric wholly predictive of success. However, in the context of the 2010 play-offs, the values of clustering (connectedness across players) and network entropy (unpredictability of ball movement) had the most consistent association with team advancement. Our analyses demonstrate the utility of network approaches in quantifying team strategy and show that testable hypotheses can be evaluated using this approach. These analyses also highlight the richness of basketball networks as a dataset for exploring the relationships between network structure and dynamics with team organization and effectiveness.
Professional Team Foundation Server 2010
Blankenship, Ed; Holliday, Grant; Keller, Brian
2011-01-01
Authoritative guide to TFS 2010 from a dream team of Microsoft insiders and MVPs!Microsoft Visual Studio Team Foundation Server (TFS) has evolved until it is now an essential tool for Microsoft?s Application Lifestyle Management suite of productivity tools, enabling collaboration within and among software development teams. By 2011, TFS will replace Microsoft?s leading source control system, VisualSourceSafe, resulting in an even greater demand for information about it. Professional Team Foundation Server 2010, written by an accomplished team of Microsoft insiders and Microsoft MVPs, provides
Directory of Open Access Journals (Sweden)
Jana Krapež Trošt
2016-01-01
Full Text Available Based on ability–motivation–opportunity theoretical framework, the study explores the interplay among team members’ proactive personalities (abilities, collective efficacy (motivation, and supportive supervision (opportunity, and their interaction in predicting team innovation. Multi-level study of 249 employees nested within 64 teams from one German and three Slovenian hi-tech companies showed that collective efficacy was positively related to team innovation. However, the effect of collective efficacy on team innovation was weaker when high levels of supportive supervision and proactivity moderated this relationship. When teams perceived lower levels of collective efficacy, team proactivity, and supportive supervision were more important for achieving higher levels of team innovation as they were when teams perceived lower levels of motivation. We discuss theoretical and practical implications
Science Partnerships Contact Us Climate Action Team & Climate Action Initiative The Climate Action programs and the state's Climate Adaptation Strategy. The CAT members are state agency secretaries and the . See CAT reports Climate Action Team Pages CAT Home Members Working Groups Reports Back to Top
Cognitive model supported team skill training
Doesburg, W.A. van; Stroomer, S.M.
2006-01-01
Complex tasks require coordinated performance by multiple team members. To perform the task effectively each team member must not only master the individual task component but also needs to function in the overall team. To increase team performance, each team member will need to acquire the relevant
Rashkovits, Sarit; Drach-Zahavy, Anat
2017-05-01
The aim of this study was to test the moderated-mediation model suggesting that nursing teams' accountability affects team effectiveness by enhancing team learning when relevant resources are available to the team. Disappointing evidence regarding improvement in nurses' safe and quality care elevate the need in broadening our knowledge regarding the factors that enhance constant learning in nursing teams. Accountability is considered as crucial for team learning and quality of care but empirical findings have shown mixed evidence. A cross-sectional design. Forty-four nursing teams participated in the study. Data were collected in 2013-2014: Head nurses completed validated questionnaires, regarding team resources for learning (time availability, team autonomy and team performance feedback), and nursing teams' effectiveness; and nurses answered questionnaires regarding teams' accountability and learning (answers were aggregated to the team level). The model was tested using a moderated-mediation analysis with resources as moderating variables, and team learning as the mediator in the team accountability-team effectiveness link. The results of a mixed linear regression show that, as expected, nursing teams' accountability was positively linked to nursing teams' learning, when time availability, and team autonomy were high rather than low, and team performance feedback was low rather than high. Nurturing team accountability is not enough for achieving team learning and subsequent team effectiveness. Rather there is a need to provide nursing teams with adequate time, autonomy, and be cautious with performance feedback, as the latter may motivate nurses to repeat routine work strategies rather than explore improved ones. © 2016 John Wiley & Sons Ltd.
Self-Managed Work Teams in Nursing Homes: Implementing and Empowering Nurse Aide Teams
Yeatts, Dale E.; Cready, Cynthia; Ray, Beth; DeWitt, Amy; Queen, Courtney
2004-01-01
Purpose: This article describes the progress of our study to examine the advantages and costs of using self-managed nurse aide teams in nursing homes, steps that are being taken to implement such teams, and management strategies being used to manage the teams. Design and Methods: A quasi-experimental design is underway where certified nurse aide…
Team Mentoring for Interdisciplinary Team Science: Lessons From K12 Scholars and Directors.
Guise, Jeanne-Marie; Geller, Stacie; Regensteiner, Judith G; Raymond, Nancy; Nagel, Joan
2017-02-01
Mentoring is critical for academic success. As science transitions to a team science model, team mentoring may have advantages. The goal of this study was to understand the process, benefits, and challenges of team mentoring relating to career development and research. A national survey was conducted of Building Interdisciplinary Research Careers in Women's Health (BIRCWH) program directors-current and former scholars from 27 active National Institutes of Health (NIH)-funded BIRCWH NIH K12 programs-to characterize and understand the value and challenges of the team approach to mentoring. Quantitative data were analyzed descriptively, and qualitative data were analyzed thematically. Responses were received from 25/27 (93%) program directors, 78/108 (72%) current scholars, and 91/162 (56%) former scholars. Scholars reported that team mentoring was beneficial to their career development (152/169; 90%) and research (148/169; 88%). Reported advantages included a diversity of opinions, expanded networking, development of stronger study designs, and modeling of different career paths. Challenges included scheduling and managing conflicting opinions. Advice by directors offered to junior faculty entering team mentoring included the following: not to be intimidated by senior mentors, be willing to navigate conflicting advice, be proactive about scheduling and guiding discussions, have an open mind to different approaches, be explicit about expectations and mentors' roles (including importance of having a primary mentor to help navigate discussions), and meet in person as a team. These findings suggest that interdisciplinary/interprofessional team mentoring has many important advantages, but that skills are required to optimally utilize multiple perspectives.
A HUBBLE DIAGRAM FROM TYPE II SUPERNOVAE BASED SOLELY ON PHOTOMETRY: THE PHOTOMETRIC COLOR METHOD
International Nuclear Information System (INIS)
De Jaeger, T.; González-Gaitán, S.; Galbany, L.; Hamuy, M.; Gutiérrez, C. P.; Kuncarayakti, H.; Anderson, J. P.; Phillips, M. M.; Campillay, A.; Castellón, S.; Hsiao, E. Y.; Morrell, N.; Stritzinger, M. D.; Contreras, C.; Bolt, L.; Burns, C. R.; Folatelli, G.; Freedman, W. L.; Krisciunas, K.; Krzeminski, W.
2015-01-01
We present a Hubble diagram of SNe II using corrected magnitudes derived only from photometry, with no input of spectral information. We use a data set from the Carnegie Supernovae Project I for which optical and near-infrared light curves were obtained. The apparent magnitude is corrected by two observables, one corresponding to the slope of the plateau in the V band and the second a color term. We obtain a dispersion of 0.44 mag using a combination of the (V − i) color and the r band and we are able to reduce the dispersion to 0.39 mag using our golden sample. A comparison of our photometric color method (PCM) with the standardized candle method (SCM) is also performed. The dispersion obtained for the SCM (which uses both photometric and spectroscopic information) is 0.29 mag, which compares with 0.43 mag from the PCM for the same SN sample. The construction of a photometric Hubble diagram is of high importance in the coming era of large photometric wide-field surveys, which will increase the detection rate of supernovae by orders of magnitude. Such numbers will prohibit spectroscopic follow up in the vast majority of cases, and hence methods must be deployed which can proceed using solely photometric data
A HUBBLE DIAGRAM FROM TYPE II SUPERNOVAE BASED SOLELY ON PHOTOMETRY: THE PHOTOMETRIC COLOR METHOD
Energy Technology Data Exchange (ETDEWEB)
De Jaeger, T.; González-Gaitán, S.; Galbany, L.; Hamuy, M.; Gutiérrez, C. P.; Kuncarayakti, H. [Millennium Institute of Astrophysics, Santiago (Chile); Anderson, J. P. [European Southern Observatory, Alonso de Córdova 3107, Casilla 19, Santiago (Chile); Phillips, M. M.; Campillay, A.; Castellón, S.; Hsiao, E. Y.; Morrell, N. [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Stritzinger, M. D.; Contreras, C. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Bolt, L. [Argelander Institut für Astronomie, Universität Bonn, Auf dem Hgel 71, D-53111 Bonn (Germany); Burns, C. R. [Observatories of the Carnegie Institution for Science, Pasadena, CA 91101 (United States); Folatelli, G. [Instituto de Astrofísica de La Plata, CONICET, Paseo del Bosque S/N, B1900FWA, La Plata (Argentina); Freedman, W. L. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Krisciunas, K. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Krzeminski, W., E-mail: dthomas@das.uchile.cl [N. Copernicus Astronomical Center, ul. Bartycka 18, 00-716 Warszawa (Poland); and others
2015-12-20
We present a Hubble diagram of SNe II using corrected magnitudes derived only from photometry, with no input of spectral information. We use a data set from the Carnegie Supernovae Project I for which optical and near-infrared light curves were obtained. The apparent magnitude is corrected by two observables, one corresponding to the slope of the plateau in the V band and the second a color term. We obtain a dispersion of 0.44 mag using a combination of the (V − i) color and the r band and we are able to reduce the dispersion to 0.39 mag using our golden sample. A comparison of our photometric color method (PCM) with the standardized candle method (SCM) is also performed. The dispersion obtained for the SCM (which uses both photometric and spectroscopic information) is 0.29 mag, which compares with 0.43 mag from the PCM for the same SN sample. The construction of a photometric Hubble diagram is of high importance in the coming era of large photometric wide-field surveys, which will increase the detection rate of supernovae by orders of magnitude. Such numbers will prohibit spectroscopic follow up in the vast majority of cases, and hence methods must be deployed which can proceed using solely photometric data.
HUBBLE TARANTULA TREASURY PROJECT. V. THE STAR CLUSTER HODGE 301: THE OLD FACE OF 30 DORADUS
Energy Technology Data Exchange (ETDEWEB)
Cignoni, M. [Department of Physics—University of Pisa, Largo Pontecorvo, 3 Pisa, I-56127 (Italy); Sabbi, E.; Marel, R. P. van der; Aloisi, A.; Panagia, N. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD, 21218 (United States); Lennon, D. J. [European Space Astronomy Centre, Apdo. de Correo 78, E-28691 Villanueva de la Canada, Madrid (Spain); Tosi, M. [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Grebel, E. K. [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, D-69120 Heidelberg (Germany); Gallagher, J. S. III [Department of Astronomy, University of Wisconsin-Madison, WI 53706 (United States); Marchi, G. de [European Space Research and Technology Centre, Keplerlaan 1, NL-2200 AG Noordwijk (Netherlands); Gouliermis, D. A. [Zentrum für Astronomie der Universität Heidelberg, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Larsen, S. [Department of Astrophysics, Radboud University, P.O. Box 9010, NL-6500 GL Nijmegen (Netherlands); Smith, L. J., E-mail: michele.cignoni@unipi.it [European Space Agency and Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
2016-12-20
Based on color–magnitude diagrams (CMDs) from the Hubble Space Telescope Hubble Tarantula Treasury Project (HTTP) survey, we present the star formation history of Hodge 301, the oldest star cluster in the Tarantula Nebula. The HTTP photometry extends faint enough to reach, for the first time, the cluster pre-main sequence (PMS) turn-on, where the PMS joins the main sequence. Using the location of this feature, along with synthetic CMDs generated with the latest PARSEC models, we find that Hodge 301 is older than previously thought, with an age between 26.5 and 31.5 Myr. From this age, we also estimate that between 38 and 61 Type II supernovae exploded in the region. The same age is derived from the main sequence turn-off, whereas the age derived from the post-main sequence stars is younger and between 20 and 25 Myr. Other relevant parameters are a total stellar mass of ≈8800 ± 800 M {sub ⊙} and average reddening E ( B − V ) ≈ 0.22–0.24 mag, with a differential reddening δE ( B − V ) ≈ 0.04 mag.
Cole, Michael S; Carter, Min Z; Zhang, Zhen
2013-11-01
We examine the effect of (in)congruence between leaders' and teams' power distance values on team effectiveness. We hypothesize that the (in)congruence between these values would differentially predict team effectiveness, with procedural justice climate serving as a mediator. Using multisource data and polynomial regression, we found that similarities (and differences) between leaders' and their teams' power distance values can have consequential effects on teams' justice climate and, ultimately, their effectiveness (viz., team performance and team organizational citizenship behavior). We conclude that to fully understand the implications of power distance, one should consider the multiple perspectives of both leaders and team members. (c) 2013 APA, all rights reserved.
Yan, Haojing; Yan, Lin; Zamojski, Michel A.; Windhorst, Rogier A.; McCarthy, Patrick J.; Fan, Xiaohui; Röttgering, Huub J. A.; Koekemoer, Anton M.; Robertson, Brant E.; Davé, Romeel; Cai, Zheng
2011-02-01
We report the first results from the Hubble Infrared Pure Parallel Imaging Extragalactic Survey, which utilizes the pure parallel orbits of the Hubble Space Telescope to do deep imaging along a large number of random sightlines. To date, our analysis includes 26 widely separated fields observed by the Wide Field Camera 3, which amounts to 122.8 arcmin2 in total area. We have found three bright Y 098-dropouts, which are candidate galaxies at z >~ 7.4. One of these objects shows an indication of peculiar variability and its nature is uncertain. The other two objects are among the brightest candidate galaxies at these redshifts known to date (L>2L*). Such very luminous objects could be the progenitors of the high-mass Lyman break galaxies observed at lower redshifts (up to z ~ 5). While our sample is still limited in size, it is much less subject to the uncertainty caused by "cosmic variance" than other samples because it is derived using fields along many random sightlines. We find that the existence of the brightest candidate at z ≈ 7.4 is not well explained by the current luminosity function (LF) estimates at z ≈ 8. However, its inferred surface density could be explained by the prediction from the LFs at z ≈ 7 if it belongs to the high-redshift tail of the galaxy population at z ≈ 7. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs 11700 and 11702.
Bouwens, R. J.; Illingworth, G. D.; Blakeslee, J. P.; Broadhurst, T. J.; Franx, M.
2004-08-01
We use the exceptional depth of the Ultra Deep Field (UDF) and UDF-parallel Advanced Camera for Surveys fields to study the sizes of high-redshift (z~2-6) galaxies and address long-standing questions about possible biases in the cosmic star formation rate due to surface brightness dimming. Contrasting B-, V-, and i-dropout samples culled from the deeper data with those obtained from the shallower Great Observatories Origins Deep Survey fields, we demonstrate that the shallower data are essentially complete at bright magnitudes to z~0.4", >~3 kpc) low surface brightness galaxies are rare. A simple comparison of the half-light radii of the Hubble Deep Field-North + Hubble Deep Field-South U-dropouts with B-, V-, and i-dropouts from the UDF shows that the sizes follow a (1+z)-1.05+/-0.21 scaling toward high redshift. A more rigorous measurement compares different scalings of our U-dropout sample with the mean profiles for a set of intermediate-magnitude (26.0dropouts from the UDF. The best fit is found with a (1+z)-0.94+0.19-0.25 size scaling (for fixed luminosity). This result is then verified by repeating this experiment with different size measures, low-redshift samples, and magnitude ranges. Very similar scalings are found for all comparisons. A robust measurement of size evolution is thereby demonstrated for galaxies from z~6 to 2.5 using data from the UDF. Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.
Using Artificial Team Members for Military Team Training in Virtual Environments
Diggelen, J. van; Heuvelink, A.; Muller, T.;
2010-01-01
Developing good team skills usually involves exercises with all team members playing their role. This approach is costly and has organizational and educational drawbacks. For the Netherlands army, we developed a more efficient and flexible approach by setting training in virtual environments, and
Healthcare management strategies: interdisciplinary team factors.
Andreatta, Pamela; Marzano, David
2012-12-01
Interdisciplinary team factors are significant contributors to clinical performance and associated patient outcomes. Quality of care and patient safety initiatives identify human factors associated with team performance as a prime improvement area for clinical patient care. The majority of references to interdisciplinary teams in obstetrics and gynecology in the literature recommends the use of multidisciplinary approaches when managing complex medical cases. The reviewed literature suggests that interdisciplinary team development is important for achieving optimally efficient and effective performance; however, few reports provide specific recommendations for how to optimally achieve these objectives in the process of providing interdisciplinary care to patients. The absence of these recommendations presents a significant challenge for those tasked with improving team performance in the workplace. The prescribed team development programs cited in the review are principally built around communication strategies and simulation-based training mechanisms. Few reports provide descriptions of optimal team-based competencies in the various contexts of obstetric and gynecology teams. However, team-based evaluation strategies and empirical data documenting the transfer of team training to applied clinical care are increasing in number and quality. Our findings suggest that research toward determining team factors that promote optimal performance in applied clinical practice requires definition of specific competencies for the variable teams serving obstetrics and gynecology.
Three images of interdisciplinary team meetings.
Crepeau, E B
1994-08-01
Teams are an essential aspect of health care today, especially in rehabilitation or chronic illness where the course of care is frequently long, complex, and unpredictable. The coordinative function of teams and their interdisciplinary aspects are thought to improve patient care because team members bring their unique professional skills together to address patient problems. This coordination is enacted through the team meeting, which typically results in an integrated care plan. This professional image of team meetings is explicit and addresses the description and provision of care as objective and rational activities. In contrast, the constructed and ritualistic images of health care team meetings are implicit and concern the less objective and rational aspects of planning care. The constructed image pertains to the definitional activity of team members as they try to understand patient troubles and achieve consensus. This process involves the individual clinical reasoning of team members and the collective reasoning of the group. The ritualistic image is that aspect of team meetings in which the team affirms and reaffirms its collective identity. Drawing from field research of geropsychiatric team meetings, this article defines and explicates these images, focusing on the constructed and ritualistic aspects of team meetings and the influence of these images on group function.
Using team cognitive work analysis to reveal healthcare team interactions in a birthing unit
Ashoori, Maryam; Burns, Catherine M.; d'Entremont, Barbara; Momtahan, Kathryn
2014-01-01
Cognitive work analysis (CWA) as an analytical approach for examining complex sociotechnical systems has shown success in modelling the work of single operators. The CWA approach incorporates social and team interactions, but a more explicit analysis of team aspects can reveal more information for systems design. In this paper, Team CWA is explored to understand teamwork within a birthing unit at a hospital. Team CWA models are derived from theories and models of teamworkand leverage the exis...
Engaged work teams in healthy companies: drivers, processes, and outcomes of team work engagement
Torrente Barberà, Pedro
2014-01-01
This PhD thesis analyses work engagement in the context of work teams taking a collective, psychosocial perspective. Throughout this thesis, the following topics will be addressed: 1) the state-of-the-art in the topic of team work engagement, 2) the measurement of team work engagement, 3) the association of team work engagement with other relevant individual-level constructs and how it fits in traditional research models in the field of Positive Occupational Health Psychology, 4) the antecede...
On multi-team predator-prey models
International Nuclear Information System (INIS)
Elettreby, M.F.; Saker, S.H.; Ahmed, E.
2005-05-01
Many creatures form teams. This has, at least, two main advantages: the first is the improvement in foraging, since looking for food in a team is more efficient than doing it alone. The second is that living in a team reduces predation risk due to early spotting of predators and that existing in a team gives a higher probability that the predator will attack another member of the team. In this paper models are given where two teams of predators interact with two teams of preys. The teams of each group (predators or preys) help each other. In this paper we propose three different versions of the multi-team predator prey model. We study the equilibrium solutions, the conditions of their local asymptotic stability, persistence and the global stability of the solution of one of the models. Some numerical simulations are done. (author)
Infrared observations of giant elliptical galaxies: (V-K) colors and the infrared Hubble diagram
International Nuclear Information System (INIS)
Grasdalen, G.L.
1980-01-01
The (V-K) colors of giant elliptical galaxies as a function of redshift are discussed. Present data are consistent with mild color evolution at z approximately 0.45. An infrared Hubble (redshift-magnitude) diagram is given. Cosmological models with q 0 =0 and no luminosity evolution are clearly excluded by the present data. A wide variety of models including those with q 0 =0 are permissible if luminosity evolution is included. Instrumental and programmatic implications of these results are summarized. (Auth.)
The Hubble IR cutoff in holographic ellipsoidal cosmologies
Energy Technology Data Exchange (ETDEWEB)
Cataldo, Mauricio [Universidad del Bio-Bio, Departamento de Fisica, Facultad de Ciencias, Concepcion (Chile); Cruz, Norman [Grupo de Cosmologia y Gravitacion-UBB, Concepcion (Chile)
2018-01-15
It is well known that for spatially flat FRW cosmologies, the holographic dark energy disfavors the Hubble parameter as a candidate for the IR cutoff. For overcoming this problem, we explore the use of this cutoff in holographic ellipsoidal cosmological models, and derive the general ellipsoidal metric induced by a such holographic energy density. Despite the drawbacks that this cutoff presents in homogeneous and isotropic universes, based on this general metric, we developed a suitable ellipsoidal holographic cosmological model, filled with a dark matter and a dark energy components. At late time stages, the cosmic evolution is dominated by a holographic anisotropic dark energy with barotropic equations of state. The cosmologies expand in all directions in accelerated manner. Since the ellipsoidal cosmologies given here are not asymptotically FRW, the deviation from homogeneity and isotropy of the universe on large cosmological scales remains constant during all cosmic evolution. This feature allows the studied holographic ellipsoidal cosmologies to be ruled by an equation of state ω = p/ρ, whose range belongs to quintessence or even phantom matter. (orig.)
Basketball Teams as Strategic Networks
Fewell, Jennifer H.; Armbruster, Dieter; Ingraham, John; Petersen, Alexander; Waters, James S.
2012-01-01
We asked how team dynamics can be captured in relation to function by considering games in the first round of the NBA 2010 play-offs as networks. Defining players as nodes and ball movements as links, we analyzed the network properties of degree centrality, clustering, entropy and flow centrality across teams and positions, to characterize the game from a network perspective and to determine whether we can assess differences in team offensive strategy by their network properties. The compiled network structure across teams reflected a fundamental attribute of basketball strategy. They primarily showed a centralized ball distribution pattern with the point guard in a leadership role. However, individual play-off teams showed variation in their relative involvement of other players/positions in ball distribution, reflected quantitatively by differences in clustering and degree centrality. We also characterized two potential alternate offensive strategies by associated variation in network structure: (1) whether teams consistently moved the ball towards their shooting specialists, measured as “uphill/downhill” flux, and (2) whether they distributed the ball in a way that reduced predictability, measured as team entropy. These network metrics quantified different aspects of team strategy, with no single metric wholly predictive of success. However, in the context of the 2010 play-offs, the values of clustering (connectedness across players) and network entropy (unpredictability of ball movement) had the most consistent association with team advancement. Our analyses demonstrate the utility of network approaches in quantifying team strategy and show that testable hypotheses can be evaluated using this approach. These analyses also highlight the richness of basketball networks as a dataset for exploring the relationships between network structure and dynamics with team organization and effectiveness. PMID:23139744
Basketball teams as strategic networks.
Directory of Open Access Journals (Sweden)
Jennifer H Fewell
Full Text Available We asked how team dynamics can be captured in relation to function by considering games in the first round of the NBA 2010 play-offs as networks. Defining players as nodes and ball movements as links, we analyzed the network properties of degree centrality, clustering, entropy and flow centrality across teams and positions, to characterize the game from a network perspective and to determine whether we can assess differences in team offensive strategy by their network properties. The compiled network structure across teams reflected a fundamental attribute of basketball strategy. They primarily showed a centralized ball distribution pattern with the point guard in a leadership role. However, individual play-off teams showed variation in their relative involvement of other players/positions in ball distribution, reflected quantitatively by differences in clustering and degree centrality. We also characterized two potential alternate offensive strategies by associated variation in network structure: (1 whether teams consistently moved the ball towards their shooting specialists, measured as "uphill/downhill" flux, and (2 whether they distributed the ball in a way that reduced predictability, measured as team entropy. These network metrics quantified different aspects of team strategy, with no single metric wholly predictive of success. However, in the context of the 2010 play-offs, the values of clustering (connectedness across players and network entropy (unpredictability of ball movement had the most consistent association with team advancement. Our analyses demonstrate the utility of network approaches in quantifying team strategy and show that testable hypotheses can be evaluated using this approach. These analyses also highlight the richness of basketball networks as a dataset for exploring the relationships between network structure and dynamics with team organization and effectiveness.
Calhoun, Tracy; Melendrez, Dave
2014-01-01
The Human Exploration Science Office (KX) provides leadership for NASA's Imagery Integration (Integration 2) Team, an affiliation of experts in the use of engineering-class imagery intended to monitor the performance of launch vehicles and crewed spacecraft in flight. Typical engineering imagery assessments include studying and characterizing the liftoff and ascent debris environments; launch vehicle and propulsion element performance; in-flight activities; and entry, landing, and recovery operations. Integration 2 support has been provided not only for U.S. Government spaceflight (e.g., Space Shuttle, Ares I-X) but also for commercial launch providers, such as Space Exploration Technologies Corporation (SpaceX) and Orbital Sciences Corporation, servicing the International Space Station. The NASA Integration 2 Team is composed of imagery integration specialists from JSC, the Marshall Space Flight Center (MSFC), and the Kennedy Space Center (KSC), who have access to a vast pool of experience and capabilities related to program integration, deployment and management of imagery assets, imagery data management, and photogrammetric analysis. The Integration 2 team is currently providing integration services to commercial demonstration flights, Exploration Flight Test-1 (EFT-1), and the Space Launch System (SLS)-based Exploration Missions (EM)-1 and EM-2. EM-2 will be the first attempt to fly a piloted mission with the Orion spacecraft. The Integration 2 Team provides the customer (both commercial and Government) with access to a wide array of imagery options - ground-based, airborne, seaborne, or vehicle-based - that are available through the Government and commercial vendors. The team guides the customer in assembling the appropriate complement of imagery acquisition assets at the customer's facilities, minimizing costs associated with market research and the risk of purchasing inadequate assets. The NASA Integration 2 capability simplifies the process of securing one
Approach to team skills training
International Nuclear Information System (INIS)
Koontz, J.L.; Roe, M.L.; Gaddy, C.D.
1987-01-01
The US commercial nuclear power industry has recognized the importance of team skills in control room operation. The desire to combine training of team interaction skills, like communications, with technical knowledge of reactor operations requires a unique approach to training. An NRC-sponsored study identified a five-phase approach to team skills training designed to be consistent with the systems approach to training currently endorsed by the NRC Policy Statement on Training and Qualification. This paper describes an approach to team skills training with emphasis on the nuclear power plant control room crew. An approach to team skills training
O'Leary, Denise Fiona
2016-01-01
It has been previously demonstrated that interactions within interprofessional teams are characterised by effective communication, shared decision-making, and knowledge sharing. This article outlines aspects of an action research study examining the emergence of these characteristics within change management teams made up of nurses, general practitioners, physiotherapists, care assistants, a health and safety officer, and a client at two residential care facilities for older people in Ireland. The theoretical concept of team psychological safety (TPS) is utilised in presenting these characteristics. TPS has been defined as an atmosphere within a team where individuals feel comfortable engaging in discussion and reflection without fear of censure. Study results suggest that TPS was an important catalyst in enhancing understanding and power sharing across professional boundaries and thus in the development of interprofessional teamwork. There were differences between the teams. In one facility, the team developed many characteristics of interprofessional teamwork while at the other there was only a limited shift. Stability in team membership and organisational norms relating to shared decision-making emerged as particularly important in accounting for differences in the development of TPS and interprofessional teamwork.
Virtual Teams and Knowledge Communication
DEFF Research Database (Denmark)
Lehtonen, Miikka; Kampf, Constance Elizabeth
2014-01-01
How does culture affect virtual teams and the knowledge communication processes in which they engage? As virtual spaces are increasingly used to support teams and establish collaboration in cross-cultural projects, the notion of cross-cultural communication can be understood as shifting from...... contextual perspective to a semiotic perspective. That is to say, although the team members are using the same vocabulary they might attach different meanings to and have different knowledge about them thus highlighting the importance of approaching virtual teams and collaboration from a semiotic perspective....... To look at how knowledge about virtual work is established in a multinational context, we interviewed members of a team that connects Finland and India. Results reveal five objects shared between the team members with varying knowledge about them. By making these differences in knowledge visible through...
Exploring team working in dentistry using a process model of team effectiveness
Willcocks, Stephen George
2018-01-01
This article explores team working in the context of dentistry in the UK. It uses an input-process-output model of team effectiveness as a framework to analyse the key issues and determine a possible way forward. The article outlines possible barriers to effective team working revealed by the application of this model. It is argued that collaborative working is important and may be facilitated by shared leadership. It discusses the implications of this and how this may be developed.
The Quantitative Analysis of a team game performance made by men basketball teams at OG 2008
Kocián, Michal
2009-01-01
Title: The quantitative analysis of e team game performance made by men basketball teams at Olympis games 2008 Aims: Find reason successes and failures of teams in Olympis game play-off using quantitative (numerical) observation of selected game statistics. Method: The thesis was made on the basic a quantitative (numerical) observation of videorecordings using KVANTÝM. Results: Obtained selected statistic desribed the most essentials events for team winning or loss. Keywords: basketball, team...
Improving supervision: a team approach.
1993-01-01
This issue of "The Family Planning Manager" outlines an interactive team supervision strategy as a means of improving family planning service quality and enabling staff to perform to their maximum potential. Such an approach to supervision requires a shift from a monitoring to a facilitative role. Because supervisory visits to the field are infrequent, the regional supervisor, clinic manager, and staff should form a team to share ongoing supervisory responsibilities. The team approach removes individual blame and builds consensus. An effective team is characterized by shared leadership roles, concrete work problems, mutual accountability, an emphasis on achieving team objectives, and problem resolution within the group. The team supervision process includes the following steps: prepare a visit plan and schedule; meet with the clinic manager and staff to explain how the visit will be conducted; supervise key activity areas (clinical, management, and personnel); conduct a problem-solving team meeting; conduct a debriefing meeting with the clinic manager; and prepare a report on the visit, including recommendations and follow-up plans. In Guatemala's Family Planning Unit, teams identify problem areas on the basis of agreement that a problem exists, belief that the problem can be solved with available resources, and individual willingness to accept responsibility for the specific actions identified to correct the problem.
Omar, Zoharah; Ahmad, Aminah
2014-01-01
Following the classic systems model of inputs, processes, and outputs, this study examined the influence of three input factors, team climate, work overload, and team leadership, on research project team effectiveness as measured by publication productivity, team member satisfaction, and job frustration. This study also examined the mediating…
Illusions of team working in health care.
West, Michael A; Lyubovnikova, Joanne
2013-01-01
The ubiquity and value of teams in healthcare are well acknowledged. However, in practice, healthcare teams vary dramatically in their structures and effectiveness in ways that can damage team processes and patient outcomes. The aim of this paper is to highlight these characteristics and to extrapolate several important aspects of teamwork that have a powerful impact on team effectiveness across healthcare contexts. The paper draws upon the literature from health services management and organisational behaviour to provide an overview of the current science of healthcare teams. Underpinned by the input-process-output framework of team effectiveness, team composition, team task, and organisational support are viewed as critical inputs that influence key team processes including team objectives, leadership and reflexivity, which in turn impact staff and patient outcomes. Team training interventions and care pathways can facilitate more effective interdisciplinary teamwork. The paper argues that the prevalence of the term "team" in healthcare makes the synthesis and advancement of the scientific understanding of healthcare teams a challenge. Future research therefore needs to better define the fundamental characteristics of teams in studies in order to ensure that findings based on real teams, rather than pseudo-like groups, are accumulated.
Developing team cognition: A role for simulation
Fernandez, Rosemarie; Shah, Sachita; Rosenman, Elizabeth D.; Kozlowski, Steve W. J.; Parker, Sarah Henrickson; Grand, James A.
2016-01-01
SUMMARY STATEMENT Simulation has had a major impact in the advancement of healthcare team training and assessment. To date, the majority of simulation-based training and assessment focuses on the teamwork behaviors that impact team performance, often ignoring critical cognitive, motivational, and affective team processes. Evidence from team science research demonstrates a strong relationship between team cognition and team performance and suggests a role for simulation in the development of this team-level construct. In this article we synthesize research from the broader team science literature to provide foundational knowledge regarding team cognition and highlight best practices for using simulation to target team cognition. PMID:28704287
Large-q correlations from a Hubble-type pion source
International Nuclear Information System (INIS)
Barghouty, A.F.; Miller, J.; Frankel, K.A.
1993-01-01
In two-pion correlation measurements from relativistic nuclear collisions, the correlation function, C 2 (q), appears to exhibit an oscillatory structure at large (q ≥100 MeV/c) relative momentum. If real, this structure may have consequences for the determination of the space-time extent of the pion source. A qualitatively similar feature is seen in cellular automaton simulations of a Lorentz gas. It has been argued phenomenologically that the q-dependent oscillations can arise from an interplay between successive scattering probabilities and density variations of an exploding pion source. To further illustrate this interplay we consider a Hubble-type free expansion model for the source in which the density is time-folded from an initial Gaussian. This allows the source expansion to enter as a dynamical variable in the source density p[r(t); t] and thus C 2 , along with any signature of the interplay between scattering and source density
Cooke, Nancy J.; Gorman, Jamie C.; Myers, Christopher W.; Duran, Jasmine L.
2013-01-01
Cognition in work teams has been predominantly understood and explained in terms of shared cognition with a focus on the similarity of static knowledge structures across individual team members. Inspired by the current zeitgeist in cognitive science, as well as by empirical data and pragmatic concerns, we offer an alternative theory of team…
Entrepreneurial team cognition: A review
de Mol, E.; Khapova, S.N.; Elfring, T.
2015-01-01
Entrepreneurial team scholars highlight the importance of studying entrepreneurial team cognition in gaining a better understanding of why some entrepreneurial teams are capable of developing teamwork leading to successful entrepreneurial outcomes while others are not. However, in the absence of a
The cohesiveness of sourcing teams
DEFF Research Database (Denmark)
Lidegaard, Nina
2015-01-01
Sourcing teams are introduced as an approach to achieving the interdepartmental integration necessary for companies to address the complexity of strategic sourcing. Companies aim at facilitating teams capable of balancing the goals and tasks of the team with departmental expectations; however...
Promoting teamwork and surgical optimization: combining TeamSTEPPS with a specialty team protocol.
Tibbs, Sheila Marie; Moss, Jacqueline
2014-11-01
This quality improvement project was a 300-day descriptive preintervention and postintervention comparison consisting of a convenience sample of 18 gynecology surgical team members. We administered the Team Strategies & Tools to Enhance Performance and Patient Safety (TeamSTEPPS®) Teamwork Perception Questionnaire to measure the perception of teamwork. In addition, we collected data regarding rates of compliance (ie, huddle, time out) and measurable surgical procedure times. Results showed a statistically significant increase in the number of team members present for each procedure, 2.34 μ before compared with 2.61 μ after (P = .038), and in the final time-out (FTO) compliance as a result of a clarification of the definition of FTO, 1.05 μ before compared with 1.18 μ after (P = .004). Additionally, there was improvement in staff members' perception of teamwork. The implementation of team training, protocols, and algorithms can enhance surgical optimization, communication, and work relationships. Copyright © 2014 AORN, Inc. Published by Elsevier Inc. All rights reserved.
Shared Leadership and Team Creativity: A Social Network Analysis in Engineering Design Teams
Directory of Open Access Journals (Sweden)
Qiong Wu
2016-06-01
Full Text Available This research explores the relationship between shared leadership and creativity in engineering design teams. To do this, a social network perspective was adopted using four measures to assess key elements of shared leadership networks. These are (a network density, (b centralization, (c efficiency and (d strength. Data was collected from a sample of 22 engineering design teams who adopt a shared leadership approach. Our results support previous findings that the density of a shared leadership network is positively related to team creativity. In contrast, we learned that centralization exerts a negative influence on it. Moreover, while we found that there is no evidence to support a positive correlation between efficiency and team creativity, we demonstrate an inverted U-shaped relationship between strength and team creativity in a shared leadership network. These findings are important because they add to the academic debate in the shared leadership area and provide valuable insights for managers.
Horwitz, Sujin K; Horwitz, Irwin B; Barshes, Neal R
2011-01-01
Previous research has demonstrated that communication failure and interpersonal conflicts are significant impediments among health-care teams to assess complex information and engage in the meaningful collaboration necessary for optimizing patient care. Despite the prolific research on the role of effective teamwork in accomplishing complex tasks, such findings have been traditionally applied to business organizations and not medical contexts. This chapter, therefore, reviews and applies four theories from the fields of organizational behavior (OB) and organization development (OD) as potential means for improving team interaction in health-care contexts. This study is unique in its approach as it addresses the long-standing problems that exist in team communication and cooperation in health-care teams by applying well-established theories from the organizational literature. The utilization and application of the theoretical constructs discussed in this work offer valuable means by which the efficacy of team work can be greatly improved in health-care organizations.
Directory of Open Access Journals (Sweden)
Ho Bin Yim
2016-02-01
Full Text Available Human capabilities, such as technical/nontechnical skills, have begun to be recognized as crucial factors for nuclear safety. One of the most common ways to improve human capabilities in general is training. The nuclear industry has constantly developed and used training as a tool to increase plant efficiency and safety. An integrated training framework was suggested for one of those efforts, especially during simulation training sessions of nuclear power plant operation teams. The developed training evaluation methods are based on measuring the levels of situation awareness of teams in terms of the level of shared confidence and consensus as well as the accuracy of team situation awareness. Verification of the developed methods was conducted by analyzing the training data of real nuclear power plant operation teams. The teams that achieved higher level of shared confidence showed better performance in solving problem situations when coupled with high consensus index values. The accuracy of nuclear power plant operation teams' situation awareness was approximately the same or showed a similar trend as that of senior reactor operators' situation awareness calculated by a situation awareness accuracy index (SAAI. Teams that had higher SAAI values performed better and faster than those that had lower SAAI values.
Friedman, Leonard H; Bernell, Stephanie L
2006-01-01
Team level tacit knowledge is related to the collective knowledge of the team members. It is the shared experience that results in the ability to successfully anticipate the reactions of teammates in typical and nontypical situations. This study evaluates how tacit knowledge and related team characteristics influence the performance of cardiothoracic surgery teams.
Fransen, Jos
2012-01-01
Fransen, J. (2012). Teaming up for learning: Team effectiveness in collaborative learning in higher education (Doctoral dissertation). November, 16, 2012, Open University in the Netherlands (CELSTEC), Heerlen, The Netherlands.
Team work on international projects
International Nuclear Information System (INIS)
Hayfield, F.
1983-01-01
A successful team will result in Project efficiency and so lead to a better achievement of the Project objectives. Such a team will be self-motivating and have a high level of morale. An effective team will also create a better context for transfer of know-how and so better prepare its members for greater roles on future Project teams. The nature of Project work forces the process of team building to recognize several facts of life. A Project team can have a life as short as one year and as long as ten years. A team usually consists of people on temporary transfer from different departments yet retaining a link of some sort to their departments of origin. It may consist of members of one company only or of several as in a joint-venture and may include Client personnel. On International Projects, the members of a team may have different nationalities and be working in a language foreign to many of them. Many of the Project people may be expatriates to the Project area on a bachelor or on a married status well away from their head or usual office. Team building is a complex organizational and human process, with no mathematical formula for the ideal solution. It starts with the selection of the right Project Manager who should be a leader, a technocrat manager and an integrator all at the same time. The Project Manager must have the authority to create the organizational and human climate that will motivate to a maximum each member of the team. Each member must understand clearly his role and realize that this contribution to the Project will influence his career development. Loyalty to the Project Manager must be possible and the Departmental Manager has to recognize this necessity. This presentation will indicate the basic steps of a team building process on a typical major international Project
A Type II Supernova Hubble diagram from the CSP-I, SDSS-II, and SNLS surveys
de Jaeger, T.; González-Gaitán, S.; Hamuy, M.; Galbany, L.; Anderson, J. P.; Phillips, M. M.; Stritzinger, M. D.; Carlberg, R. G.; Sullivan, M.; Gutiérrez, C. P.; Hook, I. M.; Howell, D. Andrew; Hsiao, E. Y.; Kuncarayakti, H.; Ruhlmann-Kleider, V.
2016-01-01
The coming era of large photometric wide-field surveys will increase the detection rate of supernovae by orders of magnitude. Such numbers will restrict spectroscopic follow-up in the vast majority of cases, and hence new methods based solely on photometric data must be developed. Here, we construct a complete Hubble diagram of Type II supernovae (SNe II) combining data from three different samples: the Carnegie Supernova Project-I, the Sloan Digital Sky Survey II SN, and th...
Bradley, Bret H; Postlethwaite, Bennett E; Klotz, Anthony C; Hamdani, Maria R; Brown, Kenneth G
2012-01-01
Past research suggests that task conflict may improve team performance under certain conditions; however, we know little about these specific conditions. On the basis of prior theory and research on conflict in teams, we argue that a climate of psychological safety is one specific context under which task conflict will improve team performance. Using evidence from 117 project teams, the present research found that psychological safety climate moderates the relationship between task conflict and performance. Specifically, task conflict and team performance were positively associated under conditions of high psychological safety. The results support the conclusion that psychological safety facilitates the performance benefits of task conflict in teams. Theoretical implications and suggestions for future research are discussed.
Pay Dispersion and Performance in Teams
Bucciol, Alessandro; Foss, Nicolai J.; Piovesan, Marco
2014-01-01
Extant research offers conflicting predictions about the effect of pay dispersion on team performance. We collected a unique dataset from the Italian soccer league to study the effect of intra-firm pay dispersion on team performance, under different definitions of what constitutes a “team”. This peculiarity of our dataset can explain the conflicting evidence. Indeed, we also find positive, null, and negative effects of pay dispersion on team performance, using the same data but different definitions of team. Our results show that when the team is considered to consist of only the members who directly contribute to the outcome, high pay dispersion has a detrimental impact on team performance. Enlarging the definition of the team causes this effect to disappear or even change direction. Finally, we find that the detrimental effect of pay dispersion is due to worse individual performance, rather than a reduction of team cooperation. PMID:25397615
Probing the z > 6 Universe with the First Hubble Frontier Fields Cluster A2744
Atek, Hakim; Richard, Johan; Kneib, Jean-Paul; Clement, Benjamin; Egami, Eiichi; Ebeling, Harald; Jauzac, Mathilde; Jullo, Eric; Laporte, Nicolas; Limousin, Marceau; Natarajan, Priyamvada
2014-05-01
The Hubble Frontier Fields program combines the capabilities of the Hubble Space Telescope (HST) with the gravitational lensing of massive galaxy clusters to probe the distant universe to an unprecedented depth. Here, we present the results of the first combined HST and Spitzer observations of the cluster A-2744. We combine the full near-infrared data with ancillary optical images to search for gravitationally lensed high-redshift (z >~ 6) galaxies. We report the detection of 15 I 814 dropout candidates at z ~ 6-7 and one Y 105 dropout at z ~ 8 in a total survey area of 1.43 arcmin2 in the source plane. The predictions of our lens model also allow us to identify five multiply imaged systems lying at redshifts between z ~ 6 and z ~ 8. Thanks to constraints from the mass distribution in the cluster, we were able to estimate the effective survey volume corrected for completeness and magnification effects. This was in turn used to estimate the rest-frame ultraviolet luminosity function (LF) at z ~ 6-8. Our LF results are generally in agreement with the most recent blank field estimates, confirming the feasibility of surveys through lensing clusters. Although based on a shallower observations than what will be achieved in the final data set including the full Advanced Camera for Survey observations, the LF presented here goes down to M UV ~-18.5, corresponding to 0.2L sstarf at z ~ 7 with one identified object at M UV ~-15 thanks to the highly magnified survey areas. This early study forecasts the power of using massive galaxy clusters as cosmic telescopes and its complementarity to blank fields. Based on observations made with the NASA/ESA Hubble Space Telescope (HST), which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs 13495 and 11689. Based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory
Lee, Myung Gyoon; Jang, In Sung; Beaton, Rachael; Seibert, Mark; Bono, Giuseppe; Madore, Barry
2017-02-01
Ultra-faint dwarf galaxies (UFDs) are the faintest known galaxies, and due to their incredibly low surface brightness, it is difficult to find them beyond the Local Group. We report a serendipitous discovery of a UFD, Fornax UFD1, in the outskirts of NGC 1316, a giant galaxy in the Fornax cluster. The new galaxy is located at a projected radius of 55 kpc in the south-east of NGC 1316. This UFD is found as a small group of resolved stars in the Hubble Space Telescope images of a halo field of NGC 1316, obtained as part of the Carnegie-Chicago Hubble Program. Resolved stars in this galaxy are consistent with being mostly metal-poor red giant branch (RGB) stars. Applying the tip of the RGB method to the mean magnitude of the two brightest RGB stars, we estimate the distance to this galaxy, 19.0 ± 1.3 Mpc. Fornax UFD1 is probably a member of the Fornax cluster. The color-magnitude diagram of these stars is matched by a 12 Gyr isochrone with low metallicity ([Fe/H] ≈ -2.4). Total magnitude and effective radius of Fornax UFD1 are MV ≈ -7.6 ± 0.2 mag and reff = 146 ± 9 pc, which are similar to those of Virgo UFD1 that was discovered recently in the intracluster field of Virgo by Jang & Lee. Fornax UFD1 is the most distant known UFD that is confirmed by resolved stars. This indicates that UFDs are ubiquitous and that more UFDs remain to be discovered in the Fornax cluster. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs #10505 and #13691.
Leadership Team Leadership Team Learn more about the expertise and technical skills of the wind Initiative and provides leadership in the focus areas of high-fidelity modeling, wind power plant controls
Kaufman, Jeffery David
2013-01-01
Conflict is not an uncommon element of team interactions and processes; however, if unchecked it can cause issues in the ability of the team to achieve maximum performance. Research on task conflict and relationship conflict by de Wit, Greer, and Jehn (2012) found that while in many cases task conflict and relationship conflict within teams can…
Teaching Engineering Students Team Work
Levi, Daniel
1998-01-01
The purpose of this manual is to provide professor's in engineering classes which the background necessary to use student team projects effectively. This manual describes some of the characteristics of student teams and how to use them in class. It provides a set of class activities and films which can be used to introduce and support student teams. Finally, a set of teaching modules used in freshmen, sophomore, and senior aeronautical engineering classes are presented. This manual was developed as part of a NASA sponsored project to improve the undergraduate education of aeronautical engineers. The project has helped to purchase a set of team work films which can be checked out from Cal Poly's Learning Resources Center in the Kennedy Library. Research for this project has included literature reviews on team work and cooperative learning; interviews, observations, and surveys of Cal Poly students from Industrial and Manufacturing Engineering, Aeronautical Engineering and Psychology; participation in the Aeronautical Engineering senior design lab; and interviews with engineering faculty. In addition to this faculty manual, there is a student team work manual which has been designed to help engineering students work better in teams.
MEASURING PRODUCTIVITY OF SOFTWARE DEVELOPMENT TEAMS
Directory of Open Access Journals (Sweden)
Goparaju Purna Sudhakar
2012-02-01
Full Text Available This paper gives an exhaustive literature review of the techniques and models available tomeasure the productivity of software development teams. Definition of productivity, measuringindividual programmer’s productivity, and measuring software development team productivity arediscussed. Based on the literature review it was found that software productivity measurement canbe done using SLOC (Source Lines of Code, function points, use case points, object points, andfeature points. Secondary research findings indicate that the team size, response time, taskcomplexity, team climate and team cohesion have an impact on software development teamproductivity. List of factors affecting the software development team productivity are studied andreviewed.
Maignan, Maxime; Koch, François-Xavier; Chaix, Jordane; Phellouzat, Pierre; Binauld, Gery; Collomb Muret, Roselyne; Cooper, Simon J; Labarère, José; Danel, Vincent; Viglino, Damien; Debaty, Guillaume
2016-04-01
Evaluation of team performances during medical simulation must rely on validated and reproducible tools. Our aim was to build and validate a French version of the Team Emergency Assessment Measure (TEAM) score, which was developed for the assessment of team performance and non-technical skills during resuscitation. A forward and backward translation of the initial TEAM score was made, with the agreement and the final validation by the original author. Ten medical teams were recruited and performed a standardized cardiac arrest simulation scenario. Teams were videotaped and nine raters evaluate non-technical skills for each team thanks to the French TEAM Score. Psychometric properties of the score were then evaluated. French TEAM score showed an excellent reliability with a Cronbach coefficient of 0.95. Mean correlation coefficient between each item and the global score range was 0.78. The inter-rater reliability measured by intraclass correlation coefficient of the global score was 0.93. Finally, expert teams had higher French TEAM score than intermediate and novice teams. The French TEAM score shows good psychometric properties to evaluate team performance during cardiac arrest simulation. Its utilization could help in the assessment of non-technical skills during simulation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Individual autonomy in work teams : the role of team autonomy, self-efficacy, and social support
Mierlo, van H.; Rutte, C.G.; Vermunt, J.K.; Kompier, M.A.J.; Doorewaard, J.A.C.M.
2006-01-01
Task autonomy is long recognized as a means to improve functioning of individuals and teams. Taking a multilevel approach, we unravelled the constructs of team and individual autonomy and studied the interplay between team autonomy, self-efficacy, and social support in determining individual
Sousa, Milton; Van Dierendonck, Dirk
2015-01-01
The research reported in this paper was designed to study the influence of shared servant leadership on team performance through the mediating effect of team behavioral integration, while validating a new short measure of shared servant leadership. A round-robin approach was used to collect data in two similar studies. Study 1 included 244 undergraduate students in 61 teams following an intense HRM business simulation of 2 weeks. The following year, study 2 included 288 students in 72 teams involved in the same simulation. The most important findings were that (1) shared servant leadership was a strong determinant of team behavioral integration, (2) information exchange worked as the main mediating process between shared servant leadership and team performance, and (3) the essence of servant leadership can be captured on the key dimensions of empowerment, humility, stewardship and accountability, allowing for a new promising shortened four-dimensional measure of shared servant leadership.
Directory of Open Access Journals (Sweden)
Pejman Ebrahimi
2016-05-01
Full Text Available Given the importance of brand management of sport teams, the objective of this study was to investigate the impact of relationship marketing dimensions, including team attachment, team trust, team involvement, and team selfexpression on team loyalty of fans of sport teams participating in Iran Azadeghan Football League. Sample size of this study included 480 fans of football teams, and structural equation modeling was used for analysis of data using Lisrel software. The results confirmed all hypotheses, except one hypothesis. Therefore, there is significant relationship between team self-expression and team attachment among football sport teams in Azadeghan Football League of Iran. The results show the importance of paying attention to fans of sports teams and use of their high potential and capacity that sports teams brand managers must pay particular attention to this enormous capacity. Regarding sports teams, the impact of relationship marketing, particularly dimensions of self-expression and team involvement was investigated for the first time in Iran.
Role Allocation and Team Structure in Command and Control Teams
2014-06-01
organizational psychology and management sciences literature show concepts such as empowered self-management and self-regulating work teams (see Cooney, 2004...tankers (FT), search units (S) and rescue units (R). Each unit is represented on the map by a numbered icon. Each type of unit is colour -coded and...Understanding team adaptation: A conceptual analysis and model. Journal of Applied Psychology , 91, 1189-1207. Cannon-Bowers, J. A., Tannenbaum
The mental health treatment team as a work group: team dynamics and the role of the leader.
Yank, G R; Barber, J W; Hargrove, D S; Whitt, P D
1992-08-01
Although treatment teams have been examined often in the mental health literature, this literature seldom addresses the crucial property of "teamness"--the key set of intangible phenomena that allow a team to function synergistically as more than the sum of its parts, and with a sense of team identity. In this paper, the concept of the work group is used to develop a framework for understanding the factors contributing to effective team functioning and identity, an their implications for the tasks of team leadership and sociotherapy: "the art of maintaining a social system in which the treatment of an individual patient can best occur" (Edelson 1970). Leadership activities that promote team cohesiveness and boundary maintenance are discussed, and suggestions are provided for ways in which the subjective experiences and emotional reactions of the leader and team members can be used to promote improved task performance and clinical care.
A multidisciplinary approach to team nursing within a low secure service: the team leader role.
Nagi, Claire; Davies, Jason; Williams, Marie; Roberts, Catherine; Lewis, Roger
2012-01-01
This article critically examines the clinical utility of redesigning a nursing practice model within the Intensive Support and Intervention Service, a new low secure mental health facility in the United Kingdom. Specifically, the "team nursing" approach to care delivery has been adapted to consist of multidisciplinary team leaders as opposed to nursing team leaders. The authors describe the role, properties, and functions of the multidisciplinary team leader approach. The authors provide examples of the benefits and challenges posed to date and the ways in which potential barriers have been overcome. Nursing care leadership can be provided by multidisciplinary staff. An adapted model of team nursing can be implemented in a low secure setting. © 2011 Wiley Periodicals, Inc.
Ability Dispersion and Team Performance
DEFF Research Database (Denmark)
Hoogendoorn, Sander; Parker, Simon C.; Van Praag, Mirjam
What is the effect of dispersed levels of cognitive ability of members of a (business) team on their team's performance? This paper reports the results of a field experiment in which 573 students in 49 teams start up and manage real companies under identical circumstances. We ensured exogenous va...
International virtual teams engineering global success
Brewer, P
2015-01-01
As a complete guide to international virtual team communication with practical problem-solving strategies, this book is a must read for managers and engineers in all stages of their professional development This book provides essential information for creating and maintaining successful international virtual teams for those who manage, participate in, or train others in international virtual teaming. Based on new studies in engineering communication, this book presents processes and principles that can help managers and engineers establish global virtual teams that work, assess the virtual team climate, and maintain the effectiveness of virtual teams across cultural boundaries. It provides knowledge and tools necessary to understand the variable contexts of global virtual teams, so that organizations are able to respond to inevitable changes in technology and the global marketplace.
The Speed of Light and the Hubble parameter: The Mass-Boom Effect
International Nuclear Information System (INIS)
Alfonso-Faus, Antonio
2008-01-01
We prove here that Newton's universal gravitation and momentum conservation laws together reproduce Weinberg's relation. It is shown that the Hubble parameter H must be built in this relation, or equivalently the age of the Universe t. Using a wave-to-particle interaction technique we then prove that the speed of light c decreases with cosmological time, and that c is proportional to the Hubble parameter H. We see the expansion of the Universe as a local effect due to the LAB value of the speed of light co taken as constant. We present a generalized red shift law and find a predicted acceleration for photons that agrees well with the result from Pioneer 10/11 anomalous acceleration. We finally present a cosmological model coherent with the above results that we call the Mass-Boom. It has a linear increase of mass m with time as a result of the speed of light c linear decrease with time, and the conservation of momentum mc. We obtain the baryonic mass parameter equal to the curvature parameter, Ω m Ω k , so that the model is of the type of the Einstein static, closed, finite, spherical, unlimited, with zero cosmological constant. This model is the cosmological view as seen by photons, neutrinos, tachyons etc. in contrast with the local view, the LAB reference. Neither dark matter nor dark energy is required by this model. With an initial constant speed of light during a short time we get inflation (an exponential expansion). This converts, during the inflation time, the Planck's fluctuation length of 10 -33 cm to the present size of the Universe (about 10 28 cm, constant from then on). Thereafter the Mass-Boom takes care to bring the initial values of the Universe (about 10 15 gr) to the value at the present time of about 10 55 gr
Energy Technology Data Exchange (ETDEWEB)
Guo, Rui-Yun [Northeastern University, Department of Physics, College of Sciences, Shenyang (China); Zhang, Xin [Northeastern University, Department of Physics, College of Sciences, Shenyang (China); Peking University, Center for High Energy Physics, Beijing (China)
2017-12-15
We revisit the constraints on inflation models by using the current cosmological observations involving the latest local measurement of the Hubble constant (H{sub 0} = 73.00 ± 1.75 km s{sup -1} Mpc{sup -1}). We constrain the primordial power spectra of both scalar and tensor perturbations with the observational data including the Planck 2015 CMB full data, the BICEP2 and Keck Array CMB B-mode data, the BAO data, and the direct measurement of H{sub 0}. In order to relieve the tension between the local determination of the Hubble constant and the other astrophysical observations, we consider the additional parameter N{sub eff} in the cosmological model. We find that, for the ΛCDM+r+N{sub eff} model, the scale invariance is only excluded at the 3.3σ level, and ΔN{sub eff} > 0 is favored at the 1.6σ level. Comparing the obtained 1σ and 2σ contours of (n{sub s},r) with the theoretical predictions of selected inflation models, we find that both the convex and the concave potentials are favored at 2σ level, the natural inflation model is excluded at more than 2σ level, the Starobinsky R{sup 2} inflation model is only favored at around 2σ level, and the spontaneously broken SUSY inflation model is now the most favored model. (orig.)
... A to Z Health Guide Your Dialysis Care Team Tweet Share Print Email Good health care is ... dialyzers (artificial kidneys) for reuse. Vascular Access Care Team If you are a hemodialysis patient, another group ...
Investigating Team Learning in a Military Context
Veestraeten, Marlies; Kyndt, Eva; Dochy, Filip
2014-01-01
As teams have become fundamental parts of today's organisations, the need for these teams to function and learn efficiently and effectively is widely emphasised. Also in military contexts team learning is vital. The current article examines team learning behaviour in military teams as it aims to cross-validate a team learning model that was…
2016-06-01
team processes, such as identifying motifs of dynamic communication exchanges which goes well beyond simple dyadic and triadic configurations; as well...new metrics and ways to formulate team processes, such as identifying motifs of dynamic communication exchanges which goes well beyond simple dyadic ...sensing, communication , information, and decision networks - Darryl Ahner (AFIT: Air Force Inst Tech) Panel Session: Mathematical Models of
Energy Technology Data Exchange (ETDEWEB)
Romano, Antonio Enea [University of Crete, Department of Physics and CCTP, Heraklion (Greece); Kyoto University, Yukawa Institute for Theoretical Physics, Kyoto (Japan); Universidad de Antioquia, Instituto de Fisica, Medellin (Colombia); Vallejo, Sergio Andres [Kyoto University, Yukawa Institute for Theoretical Physics, Kyoto (Japan); Universidad de Antioquia, Instituto de Fisica, Medellin (Colombia)
2016-04-15
In order to estimate the effects of a local structure on the Hubble parameter we calculate the low-redshift expansion for H(z) and (δH)/(H) for an observer at the center of a spherically symmetric matter distribution in the presence of a cosmological constant. We then test the accuracy of the formulas comparing them with fully relativistic non-perturbative numerical calculations for different cases for the density profile. The low-redshift expansion we obtain gives results more precise than perturbation theory since it is based on the use of an exact solution of Einstein's field equations. For larger density contrasts the low-redshift formulas accuracy improves respect to the perturbation theory accuracy because the latter is based on the assumption of a small density contrast, while the former does not rely on such an assumption. The formulas can be used to take into account the effects on the Hubble expansion parameter due to the monopole component of the local structure. If the H(z) observations will show deviations from the ΛCDM prediction compatible with the formulas we have derived, this could be considered an independent evidence of the existence of a local inhomogeneity, and the formulas could be used to determine the characteristics of this local structure. (orig.)
International Nuclear Information System (INIS)
Rhoads, James E.; Malhotra, Sangeeta; Cohen, Seth; Grogin, Norman; Hathi, Nimish; Ryan, Russell; Straughn, Amber; Windhorst, Rogier A.; Pirzkal, Norbert; Xu Chun; Koekemoer, Anton; Panagia, Nino; Dickinson, Mark; Ferreras, Ignacio; Gronwall, Caryl; Kuemmel, Martin; Walsh, Jeremy; Meurer, Gerhardt; Pasquali, Anna; Yan, H.-J.
2009-01-01
We present the faintest spectroscopically confirmed sample of z ∼ 5 Lyman break galaxies (LBGs) to date. The sample is based on slitless grism spectra of the Hubble Ultra Deep Field region from the Grism ACS Program for Extragalactic Science (GRAPES) and Probing Evolution and Reionization Spectroscopically (PEARS) projects, using the G800L grism on the Hubble Space Telescope Advanced Camera for Surveys. We report here confirmations of 39 galaxies, preselected as candidate LBGs using photometric selection criteria. We compare a 'traditional' V-dropout selection, based on the work of Giavalisco et al., to a more liberal one (with V - i > 0.9), and find that the traditional criteria are about 64% complete and 81% reliable. We also study the Lyα emission properties of our sample. We find that Lyα emission is detected in ∼1/4 of the sample, and that the liberal V-dropout color selection includes ∼55% of previously published line-selected Lyα sources. Finally, we examine our stacked two-dimensional spectra. We demonstrate that strong, spatially extended (∼1'') Lyα emission is not a generic property of these LBGs, but that a modest extension of the Lyα photosphere (compared to the starlight) may be present in those galaxies with prominent Lyα emission.
Martin, Graham P; Finn, Rachael
2011-11-01
Current healthcare policy emphasises the need for more collaborative, team-based approaches to providing care, and for a greater voice for service users in the management and delivery of care. Increasingly, policy encourages 'partnerships' between users and professionals so that users, too, effectively become team members. In examining this phenomenon, this paper draws on insights from the organisational-sociological literature on team work, which highlights the challenges of bringing together diverse professional groups, but which has not, to date, been applied in contexts where users, too, are included in teams. Using data from a qualitative study of five pilot cancer-genetics projects, in which service users were included in teams responsible for managing and developing new services, it highlights the difficulties involved in making teams of such heterogeneous members-and the paradoxes that arise when this task is achieved. It reveals how the tension between integration and specialisation of team members, highlighted in the literature on teams in general, is especially acute for service users, the distinctiveness of whose contribution is more fragile, and open to blurring. © 2011 The Authors. Sociology of Health & Illness © 2011 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.
Professionals’ views on interprofessional stroke team functioning
Directory of Open Access Journals (Sweden)
Jane Murray Cramm
2011-07-01
Full Text Available Introduction: The quality of integrated stroke care depends on smooth team functioning but professionals may not always work well together. Professionals' perspectives on the factors that influence stroke team functioning remain largely unexamined. Understanding their experiences is critical to indentifying measures to improve team functioning. The aim of this study was to identify the factors that contributed to the success of interprofessional stroke teams as perceived by team members. Methods: We distributed questionnaires to professionals within 34 integrated stroke care teams at various health care facilities in 9 Dutch regions. 558 respondents (response rate: 39% completed the questionnaire. To account for the hierarchical structure of the study design we fitted a hierarchical random-effects model. The hierarchical structure comprised 558 stroke team members (level 1 nested in 34 teams (level 2. Results: Analyses showed that personal development, social well-being, interprofessional education, communication, and role understanding significantly contributed to stroke team functioning. Team-level constructs affecting interprofessional stroke team functioning were communication and role understanding. No significant relationships were found with individual-level personal autonomy and team-level cohesion. Discussion and conclusion: Our findings suggest that interventions to improve team members' social well-being, communication, and role understanding will improve teams' performance. To further advance interprofessional team functioning, healthcare organizations should pay attention to developing professionals' interpersonal skills and interprofessional education.
Professionals’ views on interprofessional stroke team functioning
Directory of Open Access Journals (Sweden)
Jane Murray Cramm
2011-07-01
Full Text Available Introduction: The quality of integrated stroke care depends on smooth team functioning but professionals may not always work well together. Professionals' perspectives on the factors that influence stroke team functioning remain largely unexamined. Understanding their experiences is critical to indentifying measures to improve team functioning. The aim of this study was to identify the factors that contributed to the success of interprofessional stroke teams as perceived by team members. Methods: We distributed questionnaires to professionals within 34 integrated stroke care teams at various health care facilities in 9 Dutch regions. 558 respondents (response rate: 39% completed the questionnaire. To account for the hierarchical structure of the study design we fitted a hierarchical random-effects model. The hierarchical structure comprised 558 stroke team members (level 1 nested in 34 teams (level 2. Results: Analyses showed that personal development, social well-being, interprofessional education, communication, and role understanding significantly contributed to stroke team functioning. Team-level constructs affecting interprofessional stroke team functioning were communication and role understanding. No significant relationships were found with individual-level personal autonomy and team-level cohesion. Discussion and conclusion: Our findings suggest that interventions to improve team members' social well-being, communication, and role understanding will improve teams' performance. To further advance interprofessional team functioning, healthcare organizations should pay attention to developing professionals' interpersonal skills and interprofessional education.
Gevers, J.M.P.; van Eerde, W.; Rutte, C.G.
2009-01-01
In a longitudinal study among 48 project teams, we investigated how temporal consensus (i.e., the extent to which team members have a shared understanding of the temporal aspects of their collective task) affects the ability of teams to establish coordinated action and meet deadlines. In addition,
Managing creative team performance in virtual environments : An empirical study in 44 R&D teams
Kratzer, J.; Leenders, R.Th.A.J.; van Engelen, J.M.L.
Creative performance in R&D is of vital importance to organizations. Because R&D usually is organized in teams, the management of creative performance inherently refers to the team level creative performance. Over the last decades, R&D teams have become increasingly virtual. In this article we
Wittenberg-Lyles, Elaine; Oliver, Debra Parker; Demiris, George; Baldwin, Paula; Regehr, Kelly
2008-12-01
Hospice chaplains provide a specific expertise to patient and family care, however, individual roles and responsibilities that facilitate the interdisciplinary team environment are less well known. The primary aim of this study was to investigate how hospice chaplains perceive their role in interdisciplinary team meetings and to what extent hospice chaplains share common experiences within the interdisciplinary team approach in hospice. Hospice chaplains within a 10-state region participated in a 39-item phone survey about professional roles, group roles, and structural characteristics that influence their ability to participate in interdisciplinary collaboration. Findings revealed that professional role conflict is experienced, primarily with social workers. Informal group task and maintenance roles included team spiritual care advisor and conflict manager, and structural characteristics consisted of extracurricular communication outside of the organization. Although chaplains foster interdisciplinary collaboration within the hospice team, future research needs to address improvements to the chaplain's role within the interdisciplinary team process.
Sousa, Milton; Van Dierendonck, Dirk
2016-01-01
The research reported in this paper was designed to study the influence of shared servant leadership on team performance through the mediating effect of team behavioral integration, while validating a new short measure of shared servant leadership. A round-robin approach was used to collect data in two similar studies. Study 1 included 244 undergraduate students in 61 teams following an intense HRM business simulation of 2 weeks. The following year, study 2 included 288 students in 72 teams involved in the same simulation. The most important findings were that (1) shared servant leadership was a strong determinant of team behavioral integration, (2) information exchange worked as the main mediating process between shared servant leadership and team performance, and (3) the essence of servant leadership can be captured on the key dimensions of empowerment, humility, stewardship and accountability, allowing for a new promising shortened four-dimensional measure of shared servant leadership. PMID:26779104
Directory of Open Access Journals (Sweden)
Milton eSousa
2016-01-01
Full Text Available The research reported in this paper was designed to study the influence of shared servant leadership on team performance through the mediating effect of team behavioural integration, while validating a new short measure of shared servant leadership. A round-robin approach was used to collect data in two similar studies. Study 1 included 244 undergraduate students in 61 teams following an intense HRM business simulation of two weeks. The following year, study 2 included 288 students in 72 teams involved in the same simulation. The most important findings were that (1 shared servant leadership was a strong determinant of team behavioural integration, (2 information exchange worked as the main mediating process between shared servant leadership and team performance, and (3 the essence of servant leadership can be captured on the key dimensions of empowerment, humility, stewardship and accountability, allowing for a new promising shortened four-dimensional measure of shared servant leadership.
Nice Teams Finish Last The Secret to Unleashing Your Team's Maximum Potential
Miller, Brian Cole
2010-01-01
Don't rock the boat. Don't make waves. Don't offend anyone. There's a palpable feeling that clouds many team meetings and keeps them from being productive: over-politeness. And while the conflict that naturally exists in most organizations hasn't gone away, it manifests itself in passive-aggression, mediocrity, and a molasses-like inability to get anything done. Nice Teams Finish Last provides the antidote to this all-too-common tendency, giving managers, team leaders and members, and facilitators the practical support they need to battle "the nice trap" and start getting results! The book hel
Howard, Michelle; Brazil, Kevin; Akhtar-Danesh, Noori; Agarwal, Gina
2011-05-01
To determine the organizational predictors of higher scores on team climate measures as an indicator of the functioning of a family health team (FHT). Cross-sectional study using a mailed survey. Family health teams in Ontario. Twenty-one of 144 consecutively approached FHTs; 628 team members were surveyed. Scores on the team climate inventory, which assessed organizational culture type (group, developmental, rational, or hierarchical); leadership perceptions; and organizational factors, such as use of electronic medical records (EMRs), team composition, governance of the FHT, location, meetings, and time since FHT initiation. All analyses were adjusted for clustering of respondents within the FHT using a mixed random-intercepts model. The response rate was 65.8% (413 of 628); 2 were excluded from analysis, for a total of 411 participants. At the time of survey completion, there was a median of 4 physicians, 11 other health professionals, and 4 management and clerical staff per FHT. The average team climate score was 3.8 out of a possible 5. In multivariable regression analysis, leadership score, group and developmental culture types, and use of more EMR capabilities were associated with higher team climate scores. Other organizational factors, such as number of sites and size of group, were not associated with the team climate score. Culture, leadership, and EMR functionality, rather than organizational composition of the teams (eg, number of professionals on staff, practice size), were the most important factors in predicting climate in primary care teams.
Kennedy, Norelee; Armstrong, Claire; Woodward, Oonagh; Cullen, Walter
2015-07-01
Team working is an integral aspect of primary care, but barriers to effective team working can limit the effectiveness of a primary care team (PCT). The establishment of new PCTs in Ireland provides an excellent opportunity to explore team working in action. The aim of this qualitative study was to explore the experiences of team members working in a PCT. Team members (n = 19) from two PCTs were interviewed from May to June 2010 using a semi-structured interview guide. All interviews were audio-recorded and transcribed. Data were analysed using NVivo (version 8). Thematic analysis was used to explore the data. We identified five main themes that described the experiences of the team members. The themes were support for primary care, managing change, communication, evolution of roles and benefits of team working. Team members were generally supportive of primary care and had experienced benefits to their practice and to the care of their patients from participation in the team. Regular team meetings enabled communication and discussion of complex cases. Despite the significant scope for role conflict due to the varied employment arrangements of the team members, neither role nor interpersonal conflict was evident in the teams studied. In addition, despite the unusual team structure in Irish PCTs - where there is no formally appointed team leader or manager - general issues around team working and its benefits and challenges were very similar to those found in other international studies. This suggests, in contrast to some studies, that some aspects of the leadership role may not be as important in successful PCT functioning as previously thought. Nonetheless, team leadership was identified as an important issue in the further development of the teams. © 2014 John Wiley & Sons Ltd.
Commodity team motivation and performance
DEFF Research Database (Denmark)
Englyst, Linda; Jørgensen, Frances; Johansen, John
2008-01-01
In this article, an in-depth single case study is presented in order to explore and discuss the functioning of commodity teams in a global sourcing context. Specifically, the study aimed at identifying factors that may influence team members' motivation to participate in activities that create...... opportunities for synergy and coordination of purchasing. In the teams studied, motivation appeared to be influenced to some degree by a number of factors, including rewards, leadership behaviours, goal setting, and the career goals of the commodity team members. In some cases, inconsistencies between...
Commodity Team Motivation and Performance
DEFF Research Database (Denmark)
Englyst, Linda; Jørgensen, Frances; Johansen, John
2008-01-01
In this article, an in-depth single case study is presented in order to explore and discuss the functioning of commodity teams in a global sourcing context. Specifically, the study aimed at identifying factors that may influence team members' motivation to participate in activities that create...... opportunities for synergy and coordination of purchasing. In the teams studied, motivation appeared to be influenced to some degree by a number of factors, including rewards, leadership behaviours, goal setting, and the career goals of the commodity team members. In some cases, inconsistencies between...
[Multiprofessional team working in palliative medicine].
Osaka, Iwao
2013-04-01
Now, more than ever, palliative medicine has been gaining recognition for its essential role in cancer treatment. Since its beginning, it has emphasized the importance of collaboration among multidisciplinary professionals, valuing a comprehensive and holistic philosophy, addressing a wide range of hopes and suffering that patients and families experience. There are three models (approaches) for the medical teams: multidisciplinary, interdisciplinary, and transdisciplinary. Palliative care teams often choose the interdisciplinary team model, and the teams in the palliative care units may often choose the transdisciplinary team model. Recently, accumulating research has shown the clinical benefits of the interdisciplinary/transdisciplinary approach in palliative care settings. Clarifying appropriate functions and ideal features of physicians in the health care team, and enforcing the suitable team approach will contribute to improve the quality of whole medical practice beyond the framework of "palliative medicine".
Adaptive heterogeneous multi-robot teams
Energy Technology Data Exchange (ETDEWEB)
Parker, L.E.
1998-11-01
This research addresses the problem of achieving fault tolerant cooperation within small- to medium-sized teams of heterogeneous mobile robots. The author describes a novel behavior-based, fully distributed architecture, called ALLIANCE, that utilizes adaptive action selection to achieve fault tolerant cooperative control in robot missions involving loosely coupled, largely independent tasks. The robots in this architecture possess a variety of high-level functions that they can perform during a mission, and must at all times select an appropriate action based on the requirements of the mission, the activities of other robots, the current environmental conditions, and their own internal states. Since such cooperative teams often work in dynamic and unpredictable environments, the software architecture allows the team members to respond robustly and reliably to unexpected environmental changes and modifications in the robot team that may occur due to mechanical failure, the learning of new skills, or the addition or removal of robots from the team by human intervention. After presenting ALLIANCE, the author describes in detail the experimental results of an implementation of this architecture on a team of physical mobile robots performing a cooperative box pushing demonstration. These experiments illustrate the ability of ALLIANCE to achieve adaptive, fault-tolerant cooperative control amidst dynamic changes in the capabilities of the robot team.
Light dark photon and fermionic dark radiation for the Hubble constant and the structure formation
Ko, P.; Tang, Yong
2018-01-01
Motivated by the tensions in the Hubble constant $H_0$ and the structure growth $\\sigma_8$ between $Planck$ results and other low redshift measurements, we discuss some cosmological effects of a dark sector model in which dark matter (DM) interacts with fermionic dark radiation (DR) through a light gauge boson (dark photon). Such kind of models are very generic in particle physics with a dark sector with dark gauge symmetries. The effective number of neutrinos is increased by $\\delta N_{eff} ...
A knowledge-based system for monitoring the electrical power system of the Hubble Space Telescope
Eddy, Pat
1987-01-01
The design and the prototype for the expert system for the Hubble Space Telescope's electrical power system are discussed. This prototype demonstrated the capability to use real time data from a 32k telemetry stream and to perform operational health and safety status monitoring, detect trends such as battery degradation, and detect anomalies such as solar array failures. This prototype, along with the pointing control system and data management system expert systems, forms the initial Telemetry Analysis for Lockheed Operated Spacecraft (TALOS) capability.
Team Based Engineering Design Thinking
Mentzer, Nathan
2014-01-01
The objective of this research was to explore design thinking among teams of high school students. This objective was encompassed in the research question driving the inquiry: How do teams of high school students allocate time across stages of design? Design thinking on the professional level typically occurs in a team environment. Many…
Hubble Space Telescope Snapshot Survey for Resolved Companions of Galactic Cepheids
Evans, Nancy Remage; Bond, Howard E.; Schaefer, Gail H.; Mason, Brian D.; Tingle, Evan; Karovska, Margarita; Pillitteri, Ignazio
2016-05-01
We have conducted an imaging survey with the Hubble Space Telescope Wide Field Camera 3 (WFC3) of 70 Galactic Cepheids, typically within 1 kpc, with the aim of finding resolved physical companions. The WFC3 field typically covers the 0.1 pc area where companions are expected. In this paper, we identify 39 Cepheids having candidate companions, based on their positions in color-magnitude diagrams, and having separations ⩾ 5'' from the Cepheids. We use follow-up observations of 14 of these candidates with XMM-Newton, and of one of them with ROSAT, to separate X-ray-active young stars (probable physical companions) from field stars (chance alignments). Our preliminary estimate, based on the optical and X-ray observations, is that only 3% of the Cepheids in the sample have wide companions. Our survey easily detects resolved main-sequence companions as faint as spectral type K. Thus the fact that the two most probable companions (those of FF Aql and RV Sco) are earlier than type K is not simply a function of the detection limit. We find no physical companions having separations larger than 4000 au in the X-ray survey. Two Cepheids are exceptions in that they do have young companions at significantly larger separations (δ Cep and S Nor), but both belong to a cluster or a loose association, so our working model is that they are not gravitationally bound binary members, but rather cluster/association members. All of these properties provide constraints on both star formation and subsequent dynamical evolution. The low frequency of true physical companions at separations > 5'' is confirmed by examination of the subset of the nearest Cepheids and also the density of the fields. Based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.
Multidisciplinary team functioning.
Kovitz, K E; Dougan, P; Riese, R; Brummitt, J R
1984-01-01
This paper advocates the need to move beyond interdisciplinary team composition as a minimum criterion for multidisciplinary functioning in child abuse treatment. Recent developments within the field reflect the practice of shared professional responsibility for detection, case management and treatment. Adherence to this particular model for intervention requires cooperative service planning and implementation as task related functions. Implicitly, this model also carries the potential to incorporate the supportive functioning essential to effective group process. However, explicit attention to the dynamics and process of small groups has been neglected in prescriptive accounts of multidisciplinary child abuse team organization. The present paper therefore focuses upon the maintenance and enhancement aspects of multidisciplinary group functioning. First, the development and philosophy of service for the Alberta Children's Hospital Child Abuse Program are reviewed. Second, composition of the team, it's mandate for service, and the population it serves are briefly described. Third, the conceptual framework within which the program functions is outlined. Strategies for effective group functioning are presented and the difficulties encountered with this model are highlighted. Finally, recommendations are offered for planning and implementing a multidisciplinary child abuse team and for maintaining its effective group functioning.
42 CFR 456.602 - Inspection team.
2010-10-01
... 42 Public Health 4 2010-10-01 2010-10-01 false Inspection team. 456.602 Section 456.602 Public... Institutions for Mental Diseases § 456.602 Inspection team. (a) A team, as described in this section and § 456... team conducting periodic inspections must have a least one member who is at physician or registered...
Enabling Team Learning in Healthcare
Boak, George
2016-01-01
This paper is based on a study of learning processes within 35 healthcare therapy teams that took action to improve their services. The published research on team learning is introduced, and the paper suggests it is an activity that has similarities with action research and with those forms of action learning where teams address collective…
Directory of Open Access Journals (Sweden)
Bryan R. Cole
2006-07-01
Full Text Available This paper explores a new idea about the future development of science and teams, and predicts its possible applications in science, education, workforce development and research. The inter-relatedness of science and teamwork developments suggests a growing importance of team facilitators’ quality, as well as the criticality of detailed studies of teamwork processes and team consortiums to address the increasing complexity of exponential knowledge growth and work interdependency. In the future, it will become much easier to produce a highly specialised workforce, such as brain surgeons or genome engineers, than to identify, educate and develop individuals capable of the delicate and complex work of multi-team facilitation. Such individuals will become the new scientists of the millennium, having extraordinary knowledge in variety of scientific fields, unusual mix of abilities, possessing highly developed interpersonal and teamwork skills, and visionary ideas in illuminating bold strategies for new scientific discoveries. The new scientists of the millennium, through team consortium facilitation, will be able to build bridges between the multitude of diverse and extremely specialised knowledge and interdependent functions to improve systems for the further benefit of mankind.
Emergency team personnel and technical equipment
International Nuclear Information System (INIS)
Muralt, R.
1989-01-01
The most important requirements for the emergency team can be summarized in three points. 1) The emergency team must be made up of top personnel from all fields and it should be functionally equiped. 2) The emergency teams must have complete command of their equipment. 3) The members of the team must be well motivated. 1 fig