Sample records for program postimpact evaluation

  1. Post-impact alteration of the Manson impact structure

    NASA Technical Reports Server (NTRS)

    Crossey, L. J.; Mccarville, P.

    1993-01-01

    Core materials from the Manson impact site (Manson, Iowa) are examined in order to evaluate post-impact alteration processes. Diagenetic interpretation of post-impact events is based on petrologic, mineralogic, and geochemical investigation of core materials including the following: target strata, disturbed and disrupted strata, ejecta, breccias, microbreccias, and impact melt. The diagenetic study utilizes research cores obtained by the continental scientific drilling project (CSDP) at the Manson structure, as well as core and cuttings of related materials. Samples include impactites (breccias, microbreccias, and melt material), crater fill material (sedimentary clast breccias), disturbed and disrupted target rocks, and reference target material (Amoco Eisheid No. 1 materials). The study of multiple cores will permit development of a regional picture of post-impact thermal history. The specific objectives are as follows: (1) provide a detailed description of authigenic and alteration mineralogy from diverse lithologies encountered in research drill cores at the Manson impact structure, and (2) identify and relate significant post-impact mineral alteration to post-impact thermal regime (extent and duration). Results will provide mineralogical and geochemical constraints on models for post-impact processes including the following: infilling of the crater depression; cooling and hydrothermal alteration of melt rocks; and subsequent long-term, low-temperature alteration of target rocks, breccias, and melt rocks. Preliminary petrologic and x-ray diffraction examination of fracture linings and void fillings from research core M1 indicate the presence of quartz, chlorite, mixed-layer clays, gypsum/anhydrite, calcite, and minor pyrite.

  2. High-resolution seismic-reflection images across the ICDP-USGS Eyreville deep drilling site, Chesapeake Bay impact structure

    USGS Publications Warehouse

    Powars, David S.; Catchings, Rufus D.; Goldman, Mark R.; Gohn, Gregory S.; Horton, J. Wright; Edwards, Lucy E.; Rymer, Michael J.; Gandhok, Gini

    2009-01-01

    The U.S. Geological Survey (USGS) acquired two 1.4-km-long, high-resolution (~5 m vertical resolution) seismic-reflection lines in 2006 that cross near the International Continental Scientific Drilling Program (ICDP)-USGS Eyreville deep drilling site located above the late Eocene Chesapeake Bay impact structure in Virginia, USA. Five-meter spacing of seismic sources and geophones produced high-resolution images of the subsurface adjacent to the 1766-m-depth Eyreville core holes. Analysis of these lines, in the context of the core hole stratigraphy, shows that moderate-amplitude, discontinuous, dipping reflections below ~527 m correlate with a variety of Chesapeake Bay impact structure sediment and rock breccias recovered in the cores. High-amplitude, continuous, subhorizontal reflections above ~527 m depth correlate with the uppermost part of the Chesapeake Bay impact structure crater-fill sediments and postimpact Eocene to Pleistocene sediments. Reflections with ~20-30 m of relief in the uppermost part of the crater-fill and lowermost part of the postimpact section suggest differential compaction of the crater-fill materials during early postimpact time. The top of the crater-fill section also shows ~20 m of relief that appears to represent an original synimpact surface. Truncation surfaces, locally dipping reflections, and depth variations in reflection amplitudes generally correlate with the lithostrati-graphic and sequence-stratigraphic units and contacts in the core. Seismic images show apparent postimpact paleochannels that include the first possible Miocene paleochannels in the Mid-Atlantic Coastal Plain. Broad downwarping in the postim-pact section unrelated to structures in the crater fill indicates postimpact sediment compaction.

  3. Computer program for afterheat temperature distribution for mobile nuclear power plant

    NASA Technical Reports Server (NTRS)

    Parker, W. G.; Vanbibber, L. E.

    1972-01-01

    ESATA computer program was developed to analyze thermal safety aspects of post-impacted mobile nuclear power plants. Program is written in FORTRAN 4 and designed for IBM 7094/7044 direct coupled system.

  4. High-resolution seismic-reflection images across the ICDP-USGS Eyreville deep drilling site, Chesapeake Bay impact structure

    USGS Publications Warehouse

    Powars, D.S.; Catchings, R.D.; Goldman, M.R.; Gohn, G.S.; Horton, J. Wright; Edwards, L.E.; Rymer, M.J.; Gandhok, G.

    2009-01-01

    The U.S. Geological Survey (USGS) acquired two 1.4-km-long, high-resolution (??5 m vertical resolution) seismic-reflection lines in 2006 that cross near the International Continental Scientifi c Drilling Program (ICDP)-USGS Eyreville deep drilling site located above the late Eocene Chesapeake Bay impact structure in Virginia, USA. Five-meter spacing of seismic sources and geophones produced high-resolution images of the subsurface adjacent to the 1766-m-depth Eyreville core holes. Analysis of these lines, in the context of the core hole stratigraphy, shows that moderateamplitude, discontinuous, dipping reflections below ??527 m correlate with a variety of Chesapeake Bay impact structure sediment and rock breccias recovered in the cores. High-amplitude, continuous, subhorizontal reflections above ??527 m depth correlate with the uppermost part of the Chesapeake Bay impact structure crater-fi ll sediments and postimpact Eocene to Pleistocene sediments. Refl ections with ??20-30 m of relief in the uppermost part of the crater-fi ll and lowermost part of the postimpact section suggest differential compaction of the crater-fi ll materials during early postimpact time. The top of the crater-fi ll section also shows ??20 m of relief that appears to represent an original synimpact surface. Truncation surfaces, locally dipping reflections, and depth variations in reflection amplitudes generally correlate with the lithostratigraphic and sequence-stratigraphic units and contacts in the core. Seismic images show apparent postimpact paleochannels that include the fi rst possible Miocene paleochannels in the Mid-Atlantic Coastal Plain. Broad downwarping in the postimpact section unrelated to structures in the crater fi ll indicates postimpact sediment compaction. ?? 2009 The Geological Society of America.

  5. IODP-ICDP Expedition 364: Drilling the Chicxulub impact crater to understand planetary evolution and mass extinction

    NASA Astrophysics Data System (ADS)

    Gulick, S. P. S.; Morgan, J. V.

    2017-12-01

    The most recent of Earth's five largest mass extinction events occurred 66 Ma, coeval with the impact of a 12 km asteroid, striking at 60 degrees into what is today the Yucatán Peninsula, México, producing the 200 km-wide Chicxulub crater. This impact, by some estimations, drove the extinction of 75% of life on Earth at the genus level. The mass extinction event marks the boundary between the Cretaceous and Paleogene. Proposed kill mechanisms include thermal effects caused by the reentry of fast ejecta into Earth's atmosphere, dust and sulfate aerosols reducing Earth's solar insolation, ocean acidification, and metal toxicity due to the chemical make-up of the impactor. The magnitude and duration of these processes is still debated, and further evaluation of the proposed kill mechanisms requires an understanding of the mechanics of the Chicxulub impact as well as the resulting global environmental perturbations. In April and May 2016, the International Ocean Discovery Program, with co-funding from the International Continental Scientific Drilling Program, successfully cored into the Chicxulub impact crater with nearly 100% recovery. These cores include the first-ever samples of the transition from an intact peak ring through post-impact sediments. A peak ring is a discontinuous ring of mountains observed within the central basin of all large impact craters on rocky planets. Newly drilled cores include the uplifted target rocks, melt-rich impactites, hydrothermal deposits, a possible settling layer, and the resumption of carbonate sedimentation. The discovery that Chicxulub's peak ring consists of largely granitic crust uplifted by 10 km calibrates impact models and allows for observation of impact processes. At the top of the peak ring, the K-Pg boundary deposit includes a impactite sequence 130 m thick deposited by processes that range from minutes to likely years post-impact. This sequence is then overprinted by hydrothermal processes that lasted at least 100s Kyr post-impact and may have fed a subsurface ecosystem within the crater. The full recovery of life within the crater spans from immediately after impact through millions years allowing for a first-order assessment of the environmental consequences of the impact ("kill mechanisms").

  6. The relationships between impact location and post-impact ball speed, bat torsion, and ball direction in cricket batting.

    PubMed

    Peploe, C; McErlain-Naylor, S A; Harland, A R; King, M A

    2018-06-01

    Three-dimensional kinematic data of bat and ball were recorded for 239 individual shots performed by twenty batsmen ranging from club to international standard. The impact location of the ball on the bat face was determined and assessed against the resultant instantaneous post-impact ball speed and measures of post-impact bat torsion and ball direction. Significant negative linear relationships were found between post-impact ball speed and the absolute distance of impact from the midline medio-laterally and sweetspot longitudinally. Significant cubic relationships were found between the distance of impact from the midline of the bat medio-laterally and both a measure of bat torsion and the post-impact ball direction. A "sweet region" on the bat face was identified whereby impacts within 2 cm of the sweetspot in the medio-lateral direction, and 4.5 cm in the longitudinal direction, caused reductions in ball speed of less than 6% from the optimal value, and deviations in ball direction of less than 10° from the intended target. This study provides a greater understanding of the margin for error afforded to batsmen, allowing researchers to assess shot success in more detail, and highlights the importance of players generating consistently central impact locations when hitting for optimal performance.

  7. Simulation of the right-angle car collision based on identified parameters

    NASA Astrophysics Data System (ADS)

    Kostek, R.; Aleksandrowicz, P.

    2017-10-01

    This article presents an influence of contact parameters on the collision pattern of vehicles. In this case a crash of two Fiat Cinquecentos with perpendicular median planes was simulated. The first vehicle was driven with a speed 50 km/h and crashed into the other one, standing still. It is a typical collision at junctions. For the first simulation, the default parameters of the V-SIM simulation program were assumed and then the parameters identified from the crash test of a Fiat Cinquecento, published by ADAC (Allgemeiner Deutscher Automobil-Club) were used. Various post-impact movements were observed for both simulations, which demonstrates a sensitivity of the simulation results to the assumed parameters. Applying the default parameters offered by the program can lead to inadequate evaluation of the collision part due to its only approximate reconstruction, which in consequence, influences the court decision. It was demonstrated how complex it is to reconstruct the pattern of the vehicles’ crash and what problems are faced by expert witnesses who tend to use default parameters.

  8. Development of stitched/RTM composite primary structures

    NASA Technical Reports Server (NTRS)

    Kullerd, Susan M.; Dow, Marvin B.

    1992-01-01

    The goal of the NASA Advanced Composites Technology (ACT) Program is to provide the technology required to gain the full benefit of weight savings and performance offered by composite primary structures. Achieving the goal is dependent on developing composite materials and structures which are damage tolerant and economical to manufacture. Researchers at NASA LaRC and Douglas Aircraft Company are investigating stitching reinforcement combined with resin transfer molding (RTM) to create structures meeting the ACT program goals. The Douglas work is being performed under a NASA contract entitled Innovative Composites Aircraft Primary Structures (ICAPS). The research is aimed at materials, processes and structural concepts for application in both transport wings and fuselages. Empirical guidelines are being established for stitching reinforcement in primary structures. New data are presented in this paper for evaluation tests of thick (90-ply) and thin (16-ply) stitched laminates, and from selection tests of RTM composite resins. Tension strength, compression strength and post-impact compression strength data are reported. Elements of a NASA LaRC program to expand the science base for stitched/RTM composites are discussed.

  9. Scientific Drilling of Impact Craters - Well Logging and Core Analyses Using Magnetic Methods (Invited)

    NASA Astrophysics Data System (ADS)

    Fucugauchi, J. U.; Perez-Cruz, L. L.; Velasco-Villarreal, M.

    2013-12-01

    Drilling projects of impact structures provide data on the structure and stratigraphy of target, impact and post-impact lithologies, providing insight on the impact dynamics and cratering. Studies have successfully included magnetic well logging and analyses in core and cuttings, directed to characterize the subsurface stratigraphy and structure at depth. There are 170-180 impact craters documented in the terrestrial record, which is a small proportion compared to expectations derived from what is observed on the Moon, Mars and other bodies of the solar system. Knowledge of the internal 3-D deep structure of craters, critical for understanding impacts and crater formation, can best be studied by geophysics and drilling. On Earth, few craters have yet been investigated by drilling. Craters have been drilled as part of industry surveys and/or academic projects, including notably Chicxulub, Sudbury, Ries, Vredefort, Manson and many other craters. As part of the Continental ICDP program, drilling projects have been conducted on the Chicxulub, Bosumtwi, Chesapeake, Ries and El gygytgyn craters. Inclusion of continuous core recovery expanded the range of paleomagnetic and rock magnetic applications, with direct core laboratory measurements, which are part of the tools available in the ocean and continental drilling programs. Drilling studies are here briefly reviewed, with emphasis on the Chicxulub crater formed by an asteroid impact 66 Ma ago at the Cretaceous/Paleogene boundary. Chicxulub crater has no surface expression, covered by a kilometer of Cenozoic sediments, thus making drilling an essential tool. As part of our studies we have drilled eleven wells with continuous core recovery. Magnetic susceptibility logging, magnetostratigraphic, rock magnetic and fabric studies have been carried out and results used for lateral correlation, dating, formation evaluation, azimuthal core orientation and physical property contrasts. Contributions of magnetic studies on impact age, cratering, target-impactite stratigraphy, ejecta, impact dynamics, hydrothermal alterations and post-impact processes are presented. The challenges and perspectives of drilling studies of impact craters are discussed.

  10. Analysis methods for Kevlar shield response to rotor fragments

    NASA Technical Reports Server (NTRS)

    Gerstle, J. H.

    1977-01-01

    Several empirical and analytical approaches to rotor burst shield sizing are compared and principal differences in metal and fabric dynamic behavior are discussed. The application of transient structural response computer programs to predict Kevlar containment limits is described. For preliminary shield sizing, present analytical methods are useful if insufficient test data for empirical modeling are available. To provide other information useful for engineering design, analytical methods require further developments in material characterization, failure criteria, loads definition, and post-impact fragment trajectory prediction.

  11. Terrestrial Palynology of Paleocene and Eocene Sediments Above the Chicxulub Impact Crater

    NASA Astrophysics Data System (ADS)

    Smith, V.; Warny, S.; Bralower, T. J.; Jones, H.; Lowery, C. M.; Smit, J.; Vajda, V.; Vellekoop, J.; 364 Scientists, E.

    2017-12-01

    International Ocean Discovery Program (IODP) Expedition 364, with support from the International Continental Scientific Drilling Program, cored through Paleocene and Eocene sediments and into the impact structure of the Chicxulub impact crater. Three palynological studies of the post-impact section are currently underway. The two other studies are investigating the dinoflagellate palynology and terrestrial palynology of the K/Pg boundary section, while this study focuses on the early Eocene terrestrial palynology of the IODP 364 core, which has yielded a diverse and well preserved pollen assemblage. A few samples from the Early Paleocene have also been examined but organic microfossil preservation is quite poor. Samples from this core are the oldest palynological record from the Yucatan peninsula. Sample preparation and detailed abundance counts of sixty samples throughout the post-impact section are in progress, with a particular focus on the Paleocene-Eocene Thermal Maximum (PETM) and the Early Eocene Climatic Optimum (EECO). Terrestrial palynomorph assemblages will be used to reconstruct paleoclimatological conditions throughout this time period. Floral response to hyperthermal events in the IODP 364 core will be compared with records from other Gulf of Mexico and Caribbean sections. In addition to the biological and paleoclimatological implications of this research, age control from foraminiferal and nannofossil biostratigraphy, paleomagnetism, and radiometric dating will provide a chronological framework for the terrestrial pollen biostratigraphy, with applications to hydrocarbon exploration in the Wilcox Formation and age equivalent sections in the Gulf of Mexico.

  12. Preservation of Primordial Mantle in the Aftermath of a Giant Impact

    NASA Astrophysics Data System (ADS)

    Lock, S. J.; Stewart, S. T.; Mukhopadhyay, S.

    2016-12-01

    Terrestrial planets experience a number of giant impacts in the final stages of accretion. These highly energetic events force planets into hot, partially vaporized, and occasionally rapidly-rotating states. However, recent measurements of Xe and W isotopes in mantle plume-derived basalts imply that the terrestrial mantle was not homogenized during this violent stage of Earth's accretion. Understanding the physical structure of post-impact states is key for interpreting these primitive mantle signatures. Post-impact states are highly thermally stratified: the lowermost mantle has lower entropy than the rest of the mantle. Usually, the lowermost mantle is near the solidus or partially molten. The high-entropy portion of the mantle is super-liquidus, smoothly grading to a silicate vapor atmosphere. Here, we consider the competing processes acting on these distinct layers as the mantle establishes a single thermal gradient. If the whole mantle chemically mixed during cooling, then any pre-impact chemical signature would be erased. Previous work has neglected the critical time period between the highly vaporized post-impact state and a fully-condensed silicate body, i.e., a separated magma ocean and atmosphere. The post-impact structure cools rapidly by radiation from the photosphere, causing contraction of the body and redistribution of mass and angular momentum. One consequence of contraction is that the pressure in the mantle increases significantly (on the order of several to 10s GPa at the core mantle boundary) over 10s-1000s years. The increased pressure causes part of the mantle to solidify. Significantly, the timescale for pressure-induced freezing is shorter than the timescale for thermal equilibration between the low and high entropy mantle layers and the timescale for melt percolation (both >100s yrs). Therefore, pressure-induced freezing in the aftermath of a giant impact may be an important factor in preserving primordial Xe and W signatures in the lower mantle. Pressure-induced freezing of the lower mantle predicts a different chemistry than that produced by fractional crystallization of a magma ocean. The post-impact planet could inherit chemical signatures from portions of the mantles of the impacting bodies that did not re-equilibrate with the metal core or outgas volatiles.

  13. Magnetostratigraphy of the impact breccias and post-impact carbonates from borehole Yaxcopoil-1, Chicxulub impact crater, Yucatán, Mexico

    NASA Astrophysics Data System (ADS)

    Rebolledo-Vieyra, Mario; Urrutia-Fucugauchi, Jaime

    2004-06-01

    We report the magnetostratigraphy of the sedimentary sequence between the impact breccias and the post-impact carbonate sequence conducted on samples recovered by Yaxcopoil-1 (Yax-1). Samples of impact breccias show reverse polarities that span up to ~56 cm into the postimpact carbonate lithologies. We correlate these breccias to those of PEMEX boreholes Yucatán-6 and Chicxulub-1, from which we tied our magnetostratigraphy to the radiometric age from a melt sample from the Yucatán-6 borehole. Thin section analyses of the carbonate samples showed a significant amount of dark minerals and glass shards that we identified as the magnetic carriers; therefore, we propose that the mechanism of magnetic acquisition within the carbonate rocks for the interval studied is detrital remanent magnetism (DRM). With these samples, we constructed the scale of geomagnetic polarities where we find two polarities within the sequence, a reverse polarity event within the impact breccias and the base of the post-impact carbonate sequence (up to 794.07 m), and a normal polarity event in the last ~20 cm of the interval studied. The polarities recorded in the sequence analyzed are interpreted to span from chron 29r to 29n, and we propose that the reverse polarity event lies within the 29r chron. The magnetostratigraphy of the sequence studied shows that the horizon at 794.11 m deep, interpreted as the K/T boundary, lies within the geomagnetic chron 29r, which contains the K/T boundary.

  14. Effects of stacking sequence on impact damage resistance and residual strength for quasi-isotropic laminates

    NASA Technical Reports Server (NTRS)

    Dost, Ernest F.; Ilcewicz, Larry B.; Avery, William B.; Coxon, Brian R.

    1991-01-01

    Residual strength of an impacted composite laminate is dependent on details of the damage state. Stacking sequence was varied to judge its effect on damage caused by low-velocity impact. This was done for quasi-isotropic layups of a toughened composite material. Experimental observations on changes in the impact damage state and postimpact compressive performance were presented for seven different laminate stacking sequences. The applicability and limitations of analysis compared to experimental results were also discussed. Postimpact compressive behavior was found to be a strong function of the laminate stacking sequence. This relationship was found to depend on thickness, stacking sequence, size, and location of sublaminates that comprise the impact damage state. The postimpact strength for specimens with a relatively symmetric distribution of damage through the laminate thickness was accurately predicted by models that accounted for sublaminate stability and in-plane stress redistribution. An asymmetric distribution of damage in some laminate stacking sequences tended to alter specimen stability. Geometrically nonlinear finite element analysis was used to predict this behavior.

  15. A discussion of 'Anomalous quartz from the Roter Kamm impact crater, Namibia - Evidence for post-impact hydrothermal activity?'

    NASA Astrophysics Data System (ADS)

    Roedder, Edwin

    1990-11-01

    This paper presents arguments against the statement made by Koeberl et al. (1989) to the effect that various differences between the quartz of the three quartz pebbles from the Roter Kamm impact crater (Namibia) and the quartz of the pegmatites present in the basement rocks of this crater can be best interpreted as evidence that the pebbles were formed (or 'recrystallized') by a post-impact hydrothermal system. Arguments are presented that suggest that the three quartz pebbles are, most likely, fragments of a preimpact vein quartz of hydrothermal origin.

  16. Simulation of car collision with an impact block

    NASA Astrophysics Data System (ADS)

    Kostek, R.; Aleksandrowicz, P.

    2017-10-01

    This article presents the experimental results of crash test of Fiat Cinquecento performed by Allgemeiner Deutscher Automobil-Club (ADAC) and the simulation results obtained with program called V-SIM for default settings. At the next stage a wheel was blocked and the parameters of contact between the vehicle and the barrier were changed for better results matching. The following contact parameters were identified: stiffness at compression phase, stiffness at restitution phase, the coefficients of restitution and friction. The changes lead to various post-impact positions, which shows sensitivity of the results to contact parameters. V-SIM is commonly used by expert witnesses who tend to use default settings, therefore the companies offering simulation programs should identify those parameters with due diligence.

  17. Synimpact-postimpact transition inside Chesapeake Bay crater

    USGS Publications Warehouse

    Poag, Claude (Wylie)

    2002-01-01

    The transition from synimpact to postimpact sedimentation inside Chesapeake Bay impact crater began with accumulation of fallout debris, the final synimpact deposit. Evi dence of a synimpact fallout layer at this site comes from the presence of unusual, millimeter- scale, pyrite microstructures at the top of the Exmore crater-fill breccia. The porous geometry of the pyrite microstructures indicates that they originally were part of a more extensive pyrite lattice that encompassed a layer of millimeter-scale glass microspherules—fallout melt particles produced by the bolide impact. Above this microspherule layer is the initial postimpact deposit, a laminated clay-silt-sand unit, 19 cm thick. This laminated unit is a dead zone, which contains abundant stratigraphically mixed and diagenetically altered or impact-altered microfossils (foraminifera, calcareous nannofossils, dinoflagellates, ostracodes), but no evidence of indigenous biota. By extrapolation of sediment- accumulation rates, I estimate that conditions unfavorable to microbiota persisted for as little as <1 k.y. to 10 k.y. after the bolide impact. Subsequently, an abrupt improvement of the late Eocene paleoenvironment allowed species-rich assemblages of foraminifera, ostracodes, dinoflagellates, radiolarians, and calcareous nannoplankton to quickly reoccupy the crater basin, as documented in the first sample of the Chickahominy Formation above the dead zone.

  18. Synimpact-postimpact transition inside Chesapeake Bay crater

    USGS Publications Warehouse

    Poag, C.W.

    2002-01-01

    The transition from synimpact to postimpact sedimentation inside Chesapeake Bay impact crater began with accumulation of fallout debris, the final synimpact deposit. Evidence of a synimpact fallout layer at this site comes from the presence of unusual, millimeter-scale, pyrite microstructures at the top of the Exmore crater-fill breccia. The porous geometry of the pyrite microstructures indicates that they originally were part of a more extensive pyrite lattice that encompassed a layer of millimeter-scale glass microspherules-fallout melt particles produced by the bolide impact. Above this microspherule layer is the initial postimpact deposit, a laminated clay-silt-sand unit, 19 cm thick. This laminated unit is a dead zone, which contains abundant stratigraphically mixed and diagenetically altered or impact-altered microfossils (foraminifera, calcareous nannofossils, dinoflagellates, ostracodes), but no evidence of indigenous biota. By extrapolation of sediment-accumulation rates, I estimate that conditions unfavorable to microbiota persisted for as little as <1 k.y. to 10 k.y. after the bolide impact. Subsequently, an abrupt improvement of the late Eocene paleoenvironment allowed species-rich assemblages of foraminifera, ostracodes, dinoflagellates, radiolarians, and calcareous nannoplankton to quickly reoccupy the crater basin, as documented in the first sample of the Chickahominy Formation above the dead zone.

  19. Post-impact fatigue of cross-plied, through-the-thickness reinforced carbon/epoxy composites

    NASA Astrophysics Data System (ADS)

    Serdinak, Thomas E.

    1994-05-01

    An experimental investigation of the post-impact fatigue response of integrally woven carbon/epoxy composites was conducted. Five different through-the-thickness (TTT) reinforcing fibers were used in an experimental textile process that produced an integrally woven (0/90/0/90/0/90/0/90/0)(sub T) ply layup with 21K AS4 carbon tow fiber. The resin was Hercules 3501-6, and the five TTT reinforcing fibers were Kevlar, Toray carbon, AS4 carbon, glass, and IM6 carbon. The purpose of this investigation was to study the post-impact fatigue response of these material systems and to identify the optimum TTT fiber. Samples were impacted with one half inch diameter aluminum balls with an average velocity of 543 ft/sec. Post-impact static compression and constant amplitude tension-compression fatigue tests were conducted. Fatigue tests were conducted with a loading ratio of R=-5, and frequency of 4 Hz. Damage growth was monitored using x-radiographic and sectioning techniques and by examining the stress-strain response (across the impact site) throughout the fatigue tests. The static compressive stress versus far-field strain response was nearly linear for all material groups. All the samples had a transverse shear failure mode. The average compressive modulus (from far-field strain) was about 10 Msi. The average post-impact static compressive strength was about 35.5 Ksi. The IM6 carbon sample had a strength of over 40 Ksi, more than 16 percent stronger than average. There was considerable scatter in the S-N data. However, the IM6 carbon samples clearly had the best fatigue response. The response of the other materials, while worse than IM6 carbon, could not be ranked definitively. The initial damage zones caused by the impact loading and damage growth from fatigue loading were similar for all five TTT reinforcing materials. The initial damage zones were circular and consisted of delaminations, matrix cracks and ply cracks.

  20. Post-impact fatigue of cross-plied, through-the-thickness reinforced carbon/epoxy composites. M.S. Thesis - Clemson Univ.

    NASA Technical Reports Server (NTRS)

    Serdinak, Thomas E.

    1994-01-01

    An experimental investigation of the post-impact fatigue response of integrally woven carbon/epoxy composites was conducted. Five different through-the-thickness (TTT) reinforcing fibers were used in an experimental textile process that produced an integrally woven (0/90/0/90/0/90/0/90/0)(sub T) ply layup with 21K AS4 carbon tow fiber. The resin was Hercules 3501-6, and the five TTT reinforcing fibers were Kevlar, Toray carbon, AS4 carbon, glass, and IM6 carbon. The purpose of this investigation was to study the post-impact fatigue response of these material systems and to identify the optimum TTT fiber. Samples were impacted with one half inch diameter aluminum balls with an average velocity of 543 ft/sec. Post-impact static compression and constant amplitude tension-compression fatigue tests were conducted. Fatigue tests were conducted with a loading ratio of R=-5, and frequency of 4 Hz. Damage growth was monitored using x-radiographic and sectioning techniques and by examining the stress-strain response (across the impact site) throughout the fatigue tests. The static compressive stress versus far-field strain response was nearly linear for all material groups. All the samples had a transverse shear failure mode. The average compressive modulus (from far-field strain) was about 10 Msi. The average post-impact static compressive strength was about 35.5 Ksi. The IM6 carbon sample had a strength of over 40 Ksi, more than 16 percent stronger than average. There was considerable scatter in the S-N data. However, the IM6 carbon samples clearly had the best fatigue response. The response of the other materials, while worse than IM6 carbon, could not be ranked definitively. The initial damage zones caused by the impact loading and damage growth from fatigue loading were similar for all five TTT reinforcing materials. The initial damage zones were circular and consisted of delaminations, matrix cracks and ply cracks. Post-impact fatigue loading caused delamination growth, ply cracking and fiber bundle failures, typically 45 deg from impact load direction. During the initial 97 percent of fatigue life, delaminations, ply cracks and fiber bundle failures primarily grew at and near the impact site. During the final 3 percent of life, damage grew rapidly transverse to the loading direction as a through-the-thickness transverse shear failure. The stress-strain response was typically linear during the initial 50 percent of life, and stiffness dropped about 20 percent during this period. During the next 47 percent of life, stiffness dropped about 34 percent, and the stress-strain response was no longer linear. The stiffness decreased about 23 percent during the final 3 percent of life. These trends were typical of all the materials tested. Therefore, by monitoring stiffness loss, fatigue failure could be accurately anticipated.

  1. Simulations of Prebiotic Chemistry under Post-Impact Conditions on Titan.

    PubMed

    Turse, Carol; Leitner, Johannes; Firneis, Maria; Schulze-Makuch, Dirk

    2013-12-17

    The problem of how life began can be considered as a matter of basic chemistry. How did the molecules of life arise from non-biological chemistry? Stanley Miller's famous experiment in 1953, in which he produced amino acids under simulated early Earth conditions, was a huge leap forward in our understanding of this problem. Our research first simulated early Earth conditions based on Miller's experiment and we then repeated the experiment using Titan post-impact conditions. We simulated conditions that could have existed on Titan after an asteroid strike. Specifically, we simulated conditions after a potential strike in the subpolar regions of Titan that exhibit vast methane-ethane lakes. If the asteroid or comet was of sufficient size, it would also puncture the icy crust and bring up some of the subsurface liquid ammonia-water mixture. Since, O'Brian, Lorenz and Lunine showed that a liquid water-ammonia body could exist between about 102-104 years on Titan after an asteroid impact we modified our experimental conditions to include an ammonia-water mixture in the reaction medium. Here we report on the resulting amino acids found using the Titan post-impact conditions in a classical Miller experimental reaction set-up and how they differ from the simulated early Earth conditions.

  2. Validation of the RAGE Hydrocode for Impacts into Volatile-Rich Targets

    NASA Astrophysics Data System (ADS)

    Plesko, C. S.; Asphaug, E.; Coker, R. F.; Wohletz, K. H.; Korycansky, D. G.; Gisler, G. R.

    2007-12-01

    In preparation for a detailed study of large-scale impacts into the Martian surface, we have validated the RAGE hydrocode (Gittings et al., in press, CSD) against a suite of experiments and statistical models. We present comparisons of hydrocode models to centimeter-scale gas gun impacts (Nakazawa et al. 2002), an underground nuclear test (Perret, 1971), and crater scaling laws (Holsapple 1993, O'Keefe and Ahrens 1993). We have also conducted model convergence and uncertainty analyses which will be presented. Results to date are encouraging for our current model goals, and indicate areas where the hydrocode may be extended in the future. This validation work is focused on questions related to the specific problem of large impacts into volatile-rich targets. The overall goal of this effort is to be able to realistically model large-scale Noachian, and possibly post- Noachian, impacts on Mars not so much to model the crater morphology as to understand the evolution of target volatiles in the post-impact regime, to explore how large craters might set the stage for post-impact hydro- geologic evolution both locally (in the crater subsurface) and globally, due to the redistribution of volatiles from the surface and subsurface into the atmosphere. This work is performed under the auspices of IGPP and the DOE at LANL under contracts W-7405-ENG-36 and DE-AC52-06NA25396. Effort by DK and EA is sponsored by NASA's Mars Fundamental Research Program.

  3. Deep drilling into the Chesapeake Bay impact structure

    USGS Publications Warehouse

    Gohn, G.S.; Koeberl, C.; Miller, K.G.; Reimold, W.U.; Browning, J.V.; Cockell, C.S.; Horton, J. Wright; Kenkmann, T.; Kulpecz, A.A.; Powars, D.S.; Sanford, W.E.; Voytek, M.A.

    2008-01-01

    Samples from a 1.76-kilometer-deep corehole drilled near the center of the late Eocene Chesapeake Bay impact structure (Virginia, USA) reveal its geologic, hydrologic, and biologic history. We conducted stratigraphic and petrologic analyses of the cores to elucidate the timing and results of impact-melt creation and distribution, transient-cavity collapse, and ocean-water resurge. Comparison of post-impact sedimentary sequences inside and outside the structure indicates that compaction of the crater fill influenced long-term sedimentation patterns in the mid-Atlantic region. Salty connate water of the target remains in the crater fill today, where it poses a potential threat to the regional groundwater resource. Observed depth variations in microbial abundance indicate a complex history of impact-related thermal sterilization and habitat modification, and subsequent post-impact repopulation.

  4. Deep drilling into the Chesapeake Bay impact structure.

    PubMed

    Gohn, G S; Koeberl, C; Miller, K G; Reimold, W U; Browning, J V; Cockell, C S; Horton, J W; Kenkmann, T; Kulpecz, A A; Powars, D S; Sanford, W E; Voytek, M A

    2008-06-27

    Samples from a 1.76-kilometer-deep corehole drilled near the center of the late Eocene Chesapeake Bay impact structure (Virginia, USA) reveal its geologic, hydrologic, and biologic history. We conducted stratigraphic and petrologic analyses of the cores to elucidate the timing and results of impact-melt creation and distribution, transient-cavity collapse, and ocean-water resurge. Comparison of post-impact sedimentary sequences inside and outside the structure indicates that compaction of the crater fill influenced long-term sedimentation patterns in the mid-Atlantic region. Salty connate water of the target remains in the crater fill today, where it poses a potential threat to the regional groundwater resource. Observed depth variations in microbial abundance indicate a complex history of impact-related thermal sterilization and habitat modification, and subsequent post-impact repopulation.

  5. Survey of computer programs for prediction of crash response and of its experimental validation

    NASA Technical Reports Server (NTRS)

    Kamat, M. P.

    1976-01-01

    The author seeks to critically assess the potentialities of the mathematical and hybrid simulators which predict post-impact response of transportation vehicles. A strict rigorous numerical analysis of a complex phenomenon like crash may leave a lot to be desired with regard to the fidelity of mathematical simulation. Hybrid simulations on the other hand which exploit experimentally observed features of deformations appear to hold a lot of promise. MARC, ANSYS, NONSAP, DYCAST, ACTION, WHAM II and KRASH are among some of the simulators examined for their capabilities with regard to prediction of post impact response of vehicles. A review of these simulators reveals that much more by way of an analysis capability may be desirable than what is currently available. NASA's crashworthiness testing program in conjunction with similar programs of various other agencies, besides generating a large data base, will be equally useful in the validation of new mathematical concepts of nonlinear analysis and in the successful extension of other techniques in crashworthiness.

  6. On the influence of particle morphology on the post-impact ballistic response of ceramic armour materials

    NASA Astrophysics Data System (ADS)

    Hameed, Amer; Appleby-Thomas, Gareth; Wood, David; Jaansalu, Kevin

    2015-06-01

    Recent studies have shown evidence that the ballistic-resistance of fragmented (comminuted) ceramics is independent of the original strength of the material. In particular, experimental investigations into the ballistic behaviour of such fragmented ceramics have indicated that this response is correlated to shattered ceramic morphology. This suggests that careful control of ceramic microstructure - and therefore failure paths - might provide a route to optimise post-impact ballistic performance, thereby enhancing multi-hit capability. In this study, building on previous in-house work, ballistic tests were conducted using pre-formed `fragmented-ceramic' analogues based around three morphologically differing (but chemically identical) alumina feedstock materials compacted into target `pucks. In an evolution of previous work, variation of target thickness provided additional insight into an apparent morphology-based contribution to ballistic response.

  7. SPH calculations of Mars-scale collisions: The role of the equation of state, material rheologies, and numerical effects

    NASA Astrophysics Data System (ADS)

    Emsenhuber, Alexandre; Jutzi, Martin; Benz, Willy

    2018-02-01

    We model large-scale ( ≈ 2000 km) impacts on a Mars-like planet using a Smoothed Particle Hydrodynamics code. The effects of material strength and of using different Equations of State on the post-impact material and temperature distributions are investigated. The properties of the ejected material in terms of escaping and disc mass are analysed as well. We also study potential numerical effects in the context of density discontinuities and rigid body rotation. We find that in the large-scale collision regime considered here (with impact velocities of 4 km/s), the effect of material strength is substantial for the post-impact distribution of the temperature and the impactor material, while the influence of the Equation of State is more subtle and present only at very high temperatures.

  8. The impact crater as a habitat: effects of impact processing of target materials.

    PubMed

    Cockell, Charles S; Osinski, Gordon R; Lee, Pascal

    2003-01-01

    Impact structures are a rare habitat on Earth. However, where they do occur they can potentially have an important influence on the local ecology. Some of the types of habitat created in the immediate post-impact environment are not specific to the impact phenomenon, such as hydrothermal systems and crater lakes that can be found, for instance, in post-volcanic environments, albeit with different thermal characteristics than those associated with impact. However, some of the habitats created are specifically linked to processes of impact processing. Two examples of how impact processing of target materials has created novel habitats that improve the opportunities for colonization are found in the Haughton impact structure in the Canadian High Arctic. Impact-shocked rocks have become a habitat for endolithic microorganisms, and large, impact-shattered blocks of rock are used as resting sites by avifauna. However, some materials produced by an impact, such as melt sheet rocks, can make craters more biologically depauperate than the area surrounding them. Although there are no recent craters with which to study immediate post-impact colonization, these data yield insights into generalized mechanisms of how impact processing can influence post-impact succession. Because impact events are one of a number of processes that can bring localized destruction to ecosystems, understanding the manner in which impact structures are recolonized is of ecological interest. Impact craters are a universal phenomenon on solid planetary surfaces, and so they are of potential biological relevance on other planetary surfaces, particularly Mars.

  9. The impact crater as a habitat: effects of impact processing of target materials

    NASA Technical Reports Server (NTRS)

    Cockell, Charles S.; Osinski, Gordon R.; Lee, Pascal

    2003-01-01

    Impact structures are a rare habitat on Earth. However, where they do occur they can potentially have an important influence on the local ecology. Some of the types of habitat created in the immediate post-impact environment are not specific to the impact phenomenon, such as hydrothermal systems and crater lakes that can be found, for instance, in post-volcanic environments, albeit with different thermal characteristics than those associated with impact. However, some of the habitats created are specifically linked to processes of impact processing. Two examples of how impact processing of target materials has created novel habitats that improve the opportunities for colonization are found in the Haughton impact structure in the Canadian High Arctic. Impact-shocked rocks have become a habitat for endolithic microorganisms, and large, impact-shattered blocks of rock are used as resting sites by avifauna. However, some materials produced by an impact, such as melt sheet rocks, can make craters more biologically depauperate than the area surrounding them. Although there are no recent craters with which to study immediate post-impact colonization, these data yield insights into generalized mechanisms of how impact processing can influence post-impact succession. Because impact events are one of a number of processes that can bring localized destruction to ecosystems, understanding the manner in which impact structures are recolonized is of ecological interest. Impact craters are a universal phenomenon on solid planetary surfaces, and so they are of potential biological relevance on other planetary surfaces, particularly Mars.

  10. Evaluation of a subject-specific, torque-driven computer simulation model of one-handed tennis backhand groundstrokes.

    PubMed

    Kentel, Behzat B; King, Mark A; Mitchell, Sean R

    2011-11-01

    A torque-driven, subject-specific 3-D computer simulation model of the impact phase of one-handed tennis backhand strokes was evaluated by comparing performance and simulation results. Backhand strokes of an elite subject were recorded on an artificial tennis court. Over the 50-ms period after impact, good agreement was found with an overall RMS difference of 3.3° between matching simulation and performance in terms of joint and racket angles. Consistent with previous experimental research, the evaluation process showed that grip tightness and ball impact location are important factors that affect postimpact racket and arm kinematics. Associated with these factors, the model can be used for a better understanding of the eccentric contraction of the wrist extensors during one-handed backhand ground strokes, a hypothesized mechanism of tennis elbow.

  11. Full-scale Transport Controlled Impact Demonstration Program

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The Federal Aviation Administration (FAA) and NASA conducted a full-scale air-to-surface impact-survivable impact demonstration with a remotely piloted transport aircraft on 1 December 1984, at Edwards Air Force Base, California. The test article consisted of experiments, special equipment, and supporting systems, such as antimisting kerosene (AMK), crashworthiness structural/restraint, analytical modeling, cabin fire safety, flight data recorders, post-impact investigation, instrumentation/data acquisition systems, remotely piloted vehicle/flight control systems, range and flight safety provisions, etc. This report describes the aircraft, experiments, systems, activities, and events which lead up to the Controlled Impact Demonstration (CID). An overview of the final unmanned remote control flight and sequence of impact events are delineated. Preliminary post CID observations are presented.

  12. Effect of low-speed impact damage on the buckling properties of E-glass/epoxy laminates

    NASA Astrophysics Data System (ADS)

    Yapici, A.; Metin, M.

    2009-11-01

    The postimpact buck ling loads of E-glass/epoxy laminates have been measured. Composite samples with the stacking sequence [+45/-45/90/0]2s were subjected to low-speed impact loadings at various energy levels. The tests were conducted on a specially developed vertical drop-weight testing machine. The main impact parameters, such as the peak load, absorbed energy, deflection at the peak load, and damage area, were evaluated and com pared. The damaged specimens were subjected to compressive axial forces, and their buckling loads were determined. The relation between the level of impact energy and buck ling loads is investigated.

  13. Mega-supramolecules for safer, cleaner fuel

    NASA Astrophysics Data System (ADS)

    Kornfield, Julie

    Guided by the statistical mechanics of ring-chain equilibrium, we designed and synthesized polymers that self-assemble into ``mega-supramolecules'' (>=5,000 kg/mol) at low concentration (<=0.3%wt) in hydrocarbon liquids. Experimental results accord with model predictions that end-functional polymers, which distribute among cyclic and linear supramolecules, can form a significant population of mega-supramolecules at low total polymer concentration--if, and only if , the backbones are long (>400 kg/mol) and end-association strength is optimal (16-18kT). Hydrocarbon liquid fuels are the world's dominant power source (34% of global energy consumption). Transportation relies heavily on such liquids, presenting the risk of explosive post-impact fires. The collapse of the World Trade Center on September 11, 2001 inspired us to revisit polymers for mist control to mitigate post-impact fuel explosions. Rheological and both light and neutron scattering measurements of long end-functional polymers having polycyclooctadiene backbones and acid or amine end groups verify formation of mega-supramolecules. Post-impact flame propagations experiments show that mega-supramolecules control misting. Turbulent flow measurements show that mega-supramolecules reduce drag like ultra-long covalent polymers. With individual building blocks short enough to avoid hydrodynamic chain scission (400

  14. Preliminary Results From the Chicxulub Post-Impact Sediments: XRF and Physical Properties Data

    NASA Astrophysics Data System (ADS)

    Gebhardt, C.; Perez-Cruz, L. L.; Chenot, É.; Christeson, G. L.; Le Ber, E.; Lofi, J.; Nixon, C.; Rae, A.; Expedition 364 Science Party, I. I.

    2017-12-01

    In spring 2016, joint IODP/ICDP Expedition 364 drilled into the peak ring of the Chicxulub crater, offshore the Yucatan Peninsula, Mexico. A continuous core was drilled (Hole M0077A) and recovered a sequence of Paleogene post-impact rocks, suevites, impact-melt rocks and granitic basement between 505.7 m and 1334.7 m below sea floor (bsf). The Chicxulub crater was formed 66 million years ago by an impact. This catastrophic event was directly linked to a major mass extinction. For this study, we concentrate on the post-impact sediments (505.7 to 617.3 m bsf; 48 to 66 Ma). The main goal of drilling the post-impact section was to study the pace and mode of recovery of life in the ocean after the impact, and to analyze the paleoenvironmental changes across the Paleocene and Eocene. The late Paleocene and Eocene are characterized by a series of transient warming events, so-called hyperthermals that were associated with increased atmospheric pCO2. Here, we present preliminary geochemical and physical properties data from the 112 m of Paleogene sediments. XRF data show high log (Ca/Ti) values between 617 and 598 m bsf (Paleocene and early Eocene), and lower values between 598 and 505 m bsf. In particular the upper part is characterized by high-frequency fluctuations in log (Ca/Ti) reflecting repeated changes in lithology. These were presumably caused by Milankovitch cycles. Low log (Ba/Ti) values characterize the lowermost part of the record between 617 and 610, followed by a gradual increase to higher values, presumably indicating an increase in primary productivity towards the end of the Paleocene. Values remain at this higher level between 605 and 540 m bsf. Hyperthermals are characterized by strong positive log (Ba/Ti) peaks, likely pointing at highly elevated primary productivity levels during these short-lived events. Between 540 and 505 m bsf, log (Ba/Ti) values are more variable and drop occasionally to values as low as were encountered in the lowermost part. Similar to the log Ca/Ti curve, the log Ba/Ti curve is superimposed by high-frequency fluctuations. These fluctuations are also strongly visible in color reflectance measurements.

  15. Deep drilling in the Chesapeake Bay impact structure - An overview

    USGS Publications Warehouse

    Gohn, G.S.; Koeberl, C.; Miller, K.G.; Reimold, W.U.

    2009-01-01

    The late Eocene Chesapeake Bay impact structure lies buried at moderate depths below Chesapeake Bay and surrounding landmasses in southeastern Virginia, USA. Numerous characteristics made this impact structure an inviting target for scientific drilling, including the location of the impact on the Eocene continental shelf, its threelayer target structure, its large size (??85 km diameter), its status as the source of the North American tektite strewn field, its temporal association with other late Eocene terrestrial impacts, its documented effects on the regional groundwater system, and its previously unstudied effects on the deep microbial biosphere. The Chesapeake Bay Impact Structure Deep Drilling Project was designed to drill a deep, continuously cored test hole into the central part of the structure. A project workshop, funding proposals, and the acceptance of those proposals occurred during 2003-2005. Initial drilling funds were provided by the International Continental Scientific Drilling Program (ICDP) and the U.S. Geological Survey (USGS). Supplementary funds were provided by the National Aeronautics and Space Administration (NASA) Science Mission Directorate, ICDP, and USGS. Field operations were conducted at Eyreville Farm, Northampton County, Virginia, by Drilling, Observation, and Sampling of the Earth's Continental Crust (DOSECC) and the project staff during September-December 2005, resulting in two continuously cored, deep holes. The USGS and Rutgers University cored a shallow hole to 140 m in April-May 2006 to complete the recovered section from land surface to 1766 m depth. The recovered section consists of 1322 m of crater materials and 444 m of overlying postimpact Eocene to Pleistocene sediments. The crater section consists of, from base to top: basement-derived blocks of crystalline rocks (215 m); a section of suevite, impact melt rock, lithic impact breccia, and cataclasites (154 m); a thin interval of quartz sand and lithic blocks (26 m); a granite megablock (275 m); and sediment blocks and boulders, polymict, sediment-clast-dominated sedimentary breccias, and a thin upper section of stratified sediments (652 m). The cored postimpact sediments provide insight into the effects of a large continental-margin impact on subsequent coastal-plain sedimentation. This volume contains the first results of multidisciplinary studies of the Eyreville cores and related topics. The volume is divided into these sections: geologic column; borehole geophysical studies; regional geophysical studies; crystalline rocks, impactites, and impact models; sedimentary breccias; postimpact sediments; hydrologic and geothermal studies; and microbiologic studies. ?? 2009 The Geological Society of America.

  16. Geologic columns for the ICDP-USGS Eyreville A and C cores, Chesapeake Bay impact structure: Postimpact sediments, 444 to 0 m depth

    USGS Publications Warehouse

    Edwards, L.E.; Powars, D.S.; Browning, J.V.; McLaughlin, P.P.; Miller, K.G.; ,; Kulpecz, A.A.; Elbra, T.

    2009-01-01

    A 443.9-m-thick, virtually undisturbed section of postimpact deposits in the Chesapeake Bay impact structure was recovered in the Eyreville A and C cores, Northampton County, Virginia, within the "moat" of the structure's central crater. Recovered sediments are mainly fine-grained marine siliciclastics, with the exception of Pleistocene sand, clay, and gravel. The lowest postimpact unit is the upper Eocene Chickahominy Formation (443.9-350.1 m). At 93.8 m, this is the maximum thickness yet recovered for deposits that represent the return to "normal marine" sedimentation. The Drummonds Corner beds (informal) and the Old Church Formation are thin Oligocene units present between 350.1 and 344.7 m. Above the Oligocene, there is a more typical Virginia coastal plain succession. The Calvert Formation (344.7-225.4 m) includes a thin lower Miocene part overlain by a much thicker middle Miocene part. From 225.4 to 206.0 m, sediments of the middle Miocene Choptank Formation, rarely reported in the Virginia coastal plain, are present. The thick upper Miocene St. Marys and Eastover Formations (206.0-57.8 m) appear to represent a more complete succession than in the type localities. Correlation with the nearby Kiptopeke core indicates that two Pliocene units are present: Yorktown (57.8-32.2 m) and Chowan River Formations (32.2-18.3 m). Sediments at the top of the section represent an upper Pleistocene channel-fill and are assigned to the Butlers Bluff and Occohannock Members of the Nassawadox Formation (18.3-0.6 m). ?? 2009 The Geological Society of America.

  17. Ballistic impact to access the high-rate behaviour of individual silk fibres

    NASA Astrophysics Data System (ADS)

    Drodge, Daniel R.; Mortimer, Beth; Holland, Chris; Siviour, Clive R.

    2012-10-01

    A revision of a classic transverse fibre impact technique is presented, as applied to the problem of obtaining the high strain-rate constitutive behaviour of commercial Bombyx mori silk. Medium tenacity nylon was also studied. Two approaches are presented: firstly a fixed pre-stress, varied impact velocity method that derives stress-strain behaviour by inverse fit; and secondly a fixed impact velocity, varied pre-stress approach, assuming basic elastic jump conditions to obtain a locus of post-impact states. The post-impact stress-strain states obtained using the two approaches converge for silk but diverge for nylon. This we attribute to silk's fine structure being able to homogenise energy dissipation at static and dynamic deformation rates. However, the coarser microstructure of nylon results in a different loading path dependence, thus divergence in the two approaches. It was also noted that silk exhibited a comparatively stable level of impact energy absorption under varying pre-stress, when compared to nylon.

  18. Design and Testing of Braided Composite Fan Case Materials and Components

    NASA Technical Reports Server (NTRS)

    Roberts, Gary D.; Pereira, J. Michael; Braley, Michael S.; Arnold, William a.; Dorer, James D.; Watson, William R/.

    2009-01-01

    Triaxial braid composite materials are beginning to be used in fan cases for commercial gas turbine engines. The primary benefit for the use of composite materials is reduced weight and the associated reduction in fuel consumption. However, there are also cost benefits in some applications. This paper presents a description of the braided composite materials and discusses aspects of the braiding process that can be utilized for efficient fabrication of composite cases. The paper also presents an approach that was developed for evaluating the braided composite materials and composite fan cases in a ballistic impact laboratory. Impact of composite panels with a soft projectile is used for materials evaluation. Impact of composite fan cases with fan blades or blade-like projectiles is used to evaluate containment capability. A post-impact structural load test is used to evaluate the capability of the impacted fan case to survive dynamic loads during engine spool down. Validation of these new test methods is demonstrated by comparison with results of engine blade-out tests.

  19. Mechanical behavior, damage tolerance and durability of fiber metal laminates for aircraft structures

    NASA Astrophysics Data System (ADS)

    Wu, Guocai

    This study systematically explores the mechanical behavior, damage tolerance and durability of fiber metal laminates, a promising candidate materials system for next generation aerospace structures. The experimental results indicated that GLARE laminates exhibited a bilinear deformation behavior under static in-plane loading. Both an analytical constitutive model based on a modified classical lamination theory which incorporates the elasto-plastic behavior of aluminum alloy and a numerical simulation based on finite element modeling are used to predict the nonlinear stress-strain response and deformation behavior of GLARE laminates. The blunt notched strength of GLARE laminates increased with decreasing specimen width and decreasing hole diameter. The notched strength of GLARE laminates was evaluated based on a modified point stress criterion. A computer simulation based on finite element method was performed to study stress concentration and distribution around the notch and verify the analytical and experimental results of notched strength. Good agreement is obtained between the model predictions and experimental results. Experimental results also indicate that GLARE laminates exhibited superior impact properties to those of monolithic 2024-T3 aluminum alloy at low velocity impact loading. The GLARE 5-2/1 laminate with 0°/90°/90°/0° fiber configuration exhibits a better impact resistance than the GLARE 4-3/2 laminate with 0°/90°/0° fiber orientation. The characteristic impact energies, the damage area, and the permanent deflection of laminates are used to evaluate the impact damage resistance. The post-impact residual tensile strength under various damage states ranging from the plastic dent, barely visible impact damage (BVID), clearly visible impact damage (CVID) up to the complete perforation was also measured and compared. The post-impact fatigue behavior under various stress levels and impact damage states was extensively explored. The damage initiation and progression, failure modes and crack propagation under different loading conditions were investigated and identified with microscopy, SEM, X-ray radiography, and by chemically removing outer aluminum layers.

  20. Postimpact deposition in the Chesapeake Bay impact structure: Variations in eustasy, compaction, sediment supply, and passive-aggressive tectonism

    USGS Publications Warehouse

    Kulpecz, A.A.; Miller, K.G.; Browning, J.V.; Edwards, L.E.; Powars, D.S.; McLaughlin, P.P.; Harris, A.D.; Feigenson, M.D.

    2009-01-01

    The Eyreville and Exmore, Virginia, core holes were drilled in the inner basin and annular trough, respectively, of the Chesapeake Bay impact structure, and they allow us to evaluate sequence deposition in an impact crater. We provide new high-resolution geochronologic (<1 Ma) and sequence-stratigraphic interpretations of the Exmore core, identify 12 definite (and four possible) postimpact depositional sequences, and present comparisons with similar results from Eyreville and other mid- Atlantic core holes. The concurrence of increases in ??18O with Chesapeake Bay impact structure sequence boundaries indicates a primary glacioeustatic control on deposition. However, regional comparisons show the differential preservation of sequences across the mid-Atlantic margin. We explain this distribution by the compaction of impactites, regional sediment-supply changes, and the differential movement of basement structures. Upper Eocene strata are thin or missing updip and around the crater, but they thicken into the inner basin (and offshore to the southeast) due to rapid crater infilling and concurrent impactite compaction. Oligocene sequences are generally thin and highly dissected throughout the mid-Atlantic region due to sediment starvation and tectonism, except in southeastern New Jersey. Regional tectonic uplift of the Norfolk Arch coupled with a southward decrease in sediment supply resulted in: (1) largely absent Lower Miocene sections around the Chesapeake Bay impact structure compared to thick sections in New Jersey and Delaware; (2) thick Middle Miocene sequences across the Delmarva Peninsula that thin south of the Chesapeake Bay impact structure; and (3) upper Middle Miocene sections that pinch out just north of the Chesapeake Bay impact structure. Conversely, the Upper Miocene-Pliocene section is thick across Virginia, but it is poorly represented in New Jersey because of regional variations in relative subsidence. ?? 2009 The Geological Society of America.

  1. Empirical Model for Predicting Rockfall Trajectory Direction

    NASA Astrophysics Data System (ADS)

    Asteriou, Pavlos; Tsiambaos, George

    2016-03-01

    A methodology for the experimental investigation of rockfall in three-dimensional space is presented in this paper, aiming to assist on-going research of the complexity of a block's response to impact during a rockfall. An extended laboratory investigation was conducted, consisting of 590 tests with cubical and spherical blocks made of an artificial material. The effects of shape, slope angle and the deviation of the post-impact trajectory are examined as a function of the pre-impact trajectory direction. Additionally, an empirical model is proposed that estimates the deviation of the post-impact trajectory as a function of the pre-impact trajectory with respect to the slope surface and the slope angle. This empirical model is validated by 192 small-scale field tests, which are also presented in this paper. Some important aspects of the three-dimensional nature of rockfall phenomena are highlighted that have been hitherto neglected. The 3D space data provided in this study are suitable for the calibration and verification of rockfall analysis software that has become increasingly popular in design practice.

  2. Joint angles during successful and unsuccessful tennis serves kinematics of tennis serve.

    PubMed

    Göktepe, Ayhan; Ak, Emre; Söğüt, Mustafa; Karabörk, Hakan; Korkusuz, Feza

    2009-01-01

    The aim of this study was to investigate the joint angle differences in successful and unsuccessful tennis serves of junior tennis players. Nine healthy junior tennis players (5 girls, 4 boys; mean age 11.8+/-0.8 years; height 153.6+/-7.2 cm; body mass index 42.3+/-4.1 kg; playing experience 6.2+/-1.5 years) volunteered to participate in this study. They were asked to perform tennis serves as fast as they can as if they were in an actual game. Successful and unsuccessful serves were recorded using two high speed cameras and then analyzed using Pictran software. Angle changes in pre-impact, impact and post-impact phases were compared. The results of paired sample t-tests revealed nosignificant differences between successful and unsuccessful tennis serves in all three phases. This study failed to show differences between successful and unsuccessful tennis serves in pre-impact, impact and post-impact phases. However, future research with more detailed analyses would be needed to reveal the possible changes in the joints while serving.

  3. Impact of viscous droplets on different wettable surfaces: Impact phenomena, the maximum spreading factor, spreading time and post-impact oscillation.

    PubMed

    Lin, Shiji; Zhao, Binyu; Zou, Song; Guo, Jianwei; Wei, Zheng; Chen, Longquan

    2018-04-15

    In this paper, we experimentally investigated the impact dynamics of different viscous droplets on solid surfaces with diverse wettabilities. We show that the outcome of an impinging droplet is dependent on the physical property of the droplet and the wettability of the surface. Whereas only deposition was observed on lyophilic surfaces, more impact phenomena were identified on lyophobic and superlyophobic surfaces. It was found that none of the existing theoretical models can well describe the maximum spreading factor, revealing the complexity of the droplet impact dynamics and suggesting that more factors need to be considered in the theory. By using the modified capillary-inertial time, which considers the effects of liquid viscosity and surface wettability on droplet spreading, a universal scaling law describing the spreading time was obtained. Finally, we analyzed the post-impact droplet oscillation with the theory for damped harmonic oscillators and interpreted the effects of liquid viscosity and surface wettability on the oscillation by simple scaling analyses. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Rock Magnetic Study of IODP/ICDP Expedition 364 Site M0077A Drill Cores: Post-Impact Sediments, Impact Breccias, Melt, Granitic Basement and Dikes

    NASA Astrophysics Data System (ADS)

    Fucugauchi, J. U.; Perez-Cruz, L. L.; Rebolledo-Vieyra, M.; Tikoo, S.; Zylberman, W.; Lofi, J.

    2017-12-01

    Drilling at Site M0077 sampled post-impact sediments overlying a peak ring consisting of impact breccias, melt rock and granitoids. Here we focus on characterizing the peak ring using magnetic properties, which vary widely and depend on mineralogy, depositional and emplacement conditions and secondary alterations. Rock magnetic properties are integrated with Multi-Sensor Core Logger (MSCL) data, vertical seismic profile, physical properties, petrographic and chemical analyses and geophysical models. We measure low-field magnetic susceptibility at low- and high-frequencies, intensity and direction of natural remanent magnetization (NRM) and laboratory-induced isothermal (IRM) and anhysteretic (ARM) magnetizations, alternating-field demagnetization of NRM, IRM and NRM, susceptibility variation with temperature, anisotropy of magnetic susceptibility, hysteresis and IRM back-field demagnetization. Post-impact carbonates show low susceptibilities and NRM intensities, variable frequency-dependent susceptibilities and multivectorial remanences residing in low and high coercivity minerals. Hysteresis loops show low coercivity saturation magnetizations and variable paramagnetic mineral contents. Impact breccias (suevites) and melt rock show higher susceptibilities, low frequency-dependent susceptibilities, high NRM, ARM and IRM intensities and moderate ARM intensity/susceptibility ratios. Magnetic signal is dominated by fine-grained magnetite and titanomagnetites with PSD domain states. Melt rocks at the base of impactite section show the highest susceptibilities and remanence intensities. Basement section is characterized by low susceptibilities in the granites and higher values in the dikes, with NRM and ARM intensities increasing towards the base. The high susceptibilities and remanence intensities correlate with high seismic velocities, density and decreased porosity and electrical resistivity. Fracturing and alteration account for the reduced seismic velocities, density and magnetic properties in the basement section. Site M0077 is in a horizontal gradient high within the semi-circular gravity low in the crater central zone. Correlation with MSCL logs and petrographic and chemical data will allow further detailed characterization of peak ring units.

  5. Return to the Strangelove Ocean?: Preliminary results of carbon and oxygenisotope compositions of post-impact sediments, IODP Expedition 364 "Chicxulub Impact Crater"

    NASA Astrophysics Data System (ADS)

    Yamaguchi, K. E.; Ikehara, M.; Hayama, H.; Takiguchi, S.; Masuda, S.; Ogura, C.; Fujita, S.; Kurihara, E.; Matsumoto, T.; Oshio, S.; Ishihata, K.; Fuchizawa, Y.; Noda, H.; Sakurai, U.; Yamane, T.; Morgan, J. V.; Gulick, S. P. S.

    2017-12-01

    The Chicxulub crater in the northern Yucatan Peninsula, Mexico was formed by the asteroid impact at the Cretaceous-Paleogene boundary (66.0 Ma). In early 2016 the IODP Exp. 364 successfully drilled the materials from the topographic peak ring within the crater that was previously identified by seismological observations. A continuous core was recovered. The 112m-thick uppermost part of the continuous core (505.7-1334.7 mbsf) is post-impact sediments, including the PETM, that are mainly composed of carbonate with intercalation of siliciclastics and variable contents of organic carbon. More than 300 samples from the post-impact section were finely powdered for a variety of geochemical analysis. Here we report their carbon and oxygen isotope compositions of the carbonate fraction (mostly in the lower part of the analyzed section) and carbon and nitrogen isotope compositions of organic matter (mostly in the middle-upper part of the analyzed section). Isotope mass spectrometer Isoprime was used for the former analysis, and EA-irMS (elemental analyzer - isotope ratio mass spectrometer) was used for the latter analysis, both at CMCR, Kochi Univ. Depth profile of oxygen isotope compositions of carbonate fraction is variable and somewhat similar to those of Zachos et al. (2001; Science). Carbon isotope compositions of carbonate and organic carbon in the lower part of the analyzed section exhibit some excursions that could correspond to the hyperthemals in the early Paleogene. Their variable nitrogen isotope compositions reflect temporal changes in the style of biogeochemical cycles involving denitrification and nitrogen fixation. Coupled temporal changes in the carbon isotope compositions of organic and carbonate carbon immediately after the K-Pg boundary might support a Strangelove ocean (Kump, 1991; Geology), however high export production (Ba/Ti, nannoplankton and calcisphere blooms, high planktic foram richness, and diverse and abundant micro- and macrobenthic organisms) at the base of the Danian limestone cored during Exp. 364 contradict a Strangelove Ocean.

  6. Preliminary Characterization Results from the DebriSat Project

    NASA Technical Reports Server (NTRS)

    Rivero, M.; Shiotani, B.; Kleespies, J.; Toledo-Burdett, R.; Moraguez, M.; Carrasquila, M.; Fitz-Coy, N.; Liou, J.-C.; Sorge, M.; Huynh, T.

    2016-01-01

    The DebriSat project is a continuing effort sponsored by NASA and DoD to update existing break-up models using data obtained from two separate hypervelocity impact tests used to simulate on-orbit collisions. To protect the fragments resulting from the impact tests, "soft-catch" arenas made of polyurethane foam panels were utilized. After each impact test, the test chamber was cleaned and debris resulting from the catastrophic demise of the test article were collected and shipped to the University of Florida for post-impact processing. The post-impact processing activities include collecting, characterizing, and cataloging of the fragments. Since the impact tests, a team of students has been working to characterize the fragments in terms of their mass, size, shape, color and material content. The focus of the 20 months since the impact tests has been on the collection of 2 millimeters- and larger fragments resulting from impact test on the 56 kilogram-representative LEO (Low Earth Orbit) satellite referred to as DebriSat. To date we have recovered in excess of 115,000 fragments, 30,000 more than the prediction of 85,000 fragments from the existing model. We continue to collect fragments but have transitioned to the characterization phase of the post-impact activities. Since the start of the characterization phase, the focus has been to utilize automation to (i) expedite fragment characterization process and (ii) minimize human-in-the- loop. We have developed and implemented such automated processes; e.g., we have automated the data entry process to reduce operator errors during transcription of the measurement data. However, at all steps of the process, there is human oversight to ensure the integrity of the data. Additionally, we have developed and implemented repeatability and reproducibility tests to ensure that the instrumentation used in the characterization process is accurate and properly calibrated. In this paper, the implemented processes are described and preliminary results presented. Additionally, lessons learned from the implemented automations and their impacts on the integrity of the results are discussed.

  7. Integrated sequence stratigraphy of the postimpact sediments from the Eyreville core holes, Chesapeake Bay impact structure inner basin

    USGS Publications Warehouse

    Browning, J.V.; Miller, K.G.; McLaughlin, P.P.; Edwards, L.E.; Kulpecz, A.A.; Powars, D.S.; Wade, B.S.; Feigenson, M.D.; Wright, J.D.

    2009-01-01

    The Eyreville core holes provide the first continuously cored record of postimpact sequences from within the deepest part of the central Chesapeake Bay impact crater. We analyzed the upper Eocene to Pliocene postimpact sediments from the Eyreville A and C core holes for lithology (semiquantitative measurements of grain size and composition), sequence stratigraphy, and chronostratigraphy. Age is based primarily on Sr isotope stratigraphy supplemented by biostratigraphy (dinocysts, nannofossils, and planktonic foraminifers); age resolution is approximately ??0.5 Ma for early Miocene sequences and approximately ??1.0 Ma for younger and older sequences. Eocene-lower Miocene sequences are subtle, upper middle to lower upper Miocene sequences are more clearly distinguished, and upper Miocene- Pliocene sequences display a distinct facies pattern within sequences. We recognize two upper Eocene, two Oligocene, nine Miocene, three Pliocene, and one Pleistocene sequence and correlate them with those in New Jersey and Delaware. The upper Eocene through Pleistocene strata at Eyreville record changes from: (1) rapidly deposited, extremely fi ne-grained Eocene strata that probably represent two sequences deposited in a deep (>200 m) basin; to (2) highly dissected Oligocene (two very thin sequences) to lower Miocene (three thin sequences) with a long hiatus; to (3) a thick, rapidly deposited (43-73 m/Ma), very fi ne-grained, biosiliceous middle Miocene (16.5-14 Ma) section divided into three sequences (V5-V3) deposited in middle neritic paleoenvironments; to (4) a 4.5-Ma-long hiatus (12.8-8.3 Ma); to (5) sandy, shelly upper Miocene to Pliocene strata (8.3-2.0 Ma) divided into six sequences deposited in shelf and shoreface environments; and, last, to (6) a sandy middle Pleistocene paralic sequence (~400 ka). The Eyreville cores thus record the fi lling of a deep impact-generated basin where the timing of sequence boundaries is heavily infl uenced by eustasy. ?? 2009 The Geological Society of America.

  8. A Biomechanical Analysis of the Karate Chop.

    ERIC Educational Resources Information Center

    Cavanagh, Peter R.; Landa, Jean

    Although the sport of karate has been somewhat neglected by scientists, the following two isolated biomechanical studies exist in literature: (1) tracings of a karate chop in two planes were presented, but no data was given concerning the rates of movement of the limb segments, and (2) pre- and postimpact phenomena of five subjects were studied,…

  9. Sex-Based Differences in Knee Kinetics With Anterior Cruciate Ligament Strain on Cadaveric Impact Simulations

    PubMed Central

    Schilaty, Nathan D.; Bates, Nathaniel A.; Nagelli, Christopher; Krych, Aaron J.; Hewett, Timothy E.

    2018-01-01

    Background: Females are at an increased risk of sustaining noncontact knee ligament injuries as compared with their male counterparts. The kinetics that load the anterior cruciate ligament (ACL) are still under dispute in the literature. Purpose/Hypothesis: The purpose of this study was to determine whether there are differences in knee kinetics between the sexes that lead to greater ACL strain in females when similar external loads are applied during a simulated drop vertical jump landing task. It was hypothesized that female limbs would demonstrate significant differences in knee abduction moment that predispose females to ACL injury when compared with males. Study Design: Controlled laboratory study. Methods: Motion analysis data of 67 athletes who performed a drop vertical jump were collected. The kinematic and kinetic data were used to categorize tertiles of relative risk, and these values were input into a cadaveric impact simulator to assess ligamentous loads during the simulated landing task. Uni- and multiaxial load cells and differential variable reluctance transducer strain sensors were utilized to collect kinetic data and maximum ACL strain for analysis. Conditions of external loads applied to the cadaveric limbs were systematically varied and randomized. Data were analyzed with 2-way repeated-measures analysis of variance and the Fisher exact test. Results: Five kinetic parameters were evaluated. Of the 5 kinetic variables, only knee abduction moment (KAM) demonstrated significant differences in females as compared with males (F 1,136 = 4.398, P = .038). When normalized to height and weight, this difference between males and females increased in significance (F 1,136 = 7.155, P = .008). Compared with males, females exhibited a 10.3-N·m increased knee abduction torque at 66 milliseconds postimpact and a 22.3-N·m increased abduction torque at 100 milliseconds postimpact. For loading condition, the condition of “maximum ACL strain” demonstrated a maximum difference of 54.3-N·m increased abduction torque and 74.5-N·m increased abduction torque at 66 milliseconds postimpact. Conclusion: Under the tested conditions, increased external loads led to increased medial knee translation force, knee abduction moment, and external knee moment. Females exhibited greater forces and moments at the knee, especially at KAM, when loaded in similar conditions. As these KAM loads are associated with increased load and strain on the ACL, the sex-based differences observed in the present study may account for a portion of the underlying mechanics that predispose females to ACL injury as compared with males in a controlled simulated athletic task. Clinical Relevance: KAM increases strain to the ACL under clinically representative loading. Additionally, this work establishes the biomechanical characteristics of knee loading between sexes. PMID:29568787

  10. Sex-Based Differences in Knee Kinetics With Anterior Cruciate Ligament Strain on Cadaveric Impact Simulations.

    PubMed

    Schilaty, Nathan D; Bates, Nathaniel A; Nagelli, Christopher; Krych, Aaron J; Hewett, Timothy E

    2018-03-01

    Females are at an increased risk of sustaining noncontact knee ligament injuries as compared with their male counterparts. The kinetics that load the anterior cruciate ligament (ACL) are still under dispute in the literature. The purpose of this study was to determine whether there are differences in knee kinetics between the sexes that lead to greater ACL strain in females when similar external loads are applied during a simulated drop vertical jump landing task. It was hypothesized that female limbs would demonstrate significant differences in knee abduction moment that predispose females to ACL injury when compared with males. Controlled laboratory study. Motion analysis data of 67 athletes who performed a drop vertical jump were collected. The kinematic and kinetic data were used to categorize tertiles of relative risk, and these values were input into a cadaveric impact simulator to assess ligamentous loads during the simulated landing task. Uni- and multiaxial load cells and differential variable reluctance transducer strain sensors were utilized to collect kinetic data and maximum ACL strain for analysis. Conditions of external loads applied to the cadaveric limbs were systematically varied and randomized. Data were analyzed with 2-way repeated-measures analysis of variance and the Fisher exact test. Five kinetic parameters were evaluated. Of the 5 kinetic variables, only knee abduction moment (KAM) demonstrated significant differences in females as compared with males ( F 1,136 = 4.398, P = .038). When normalized to height and weight, this difference between males and females increased in significance ( F 1,136 = 7.155, P = .008). Compared with males, females exhibited a 10.3-N·m increased knee abduction torque at 66 milliseconds postimpact and a 22.3-N·m increased abduction torque at 100 milliseconds postimpact. For loading condition, the condition of "maximum ACL strain" demonstrated a maximum difference of 54.3-N·m increased abduction torque and 74.5-N·m increased abduction torque at 66 milliseconds postimpact. Under the tested conditions, increased external loads led to increased medial knee translation force, knee abduction moment, and external knee moment. Females exhibited greater forces and moments at the knee, especially at KAM, when loaded in similar conditions. As these KAM loads are associated with increased load and strain on the ACL, the sex-based differences observed in the present study may account for a portion of the underlying mechanics that predispose females to ACL injury as compared with males in a controlled simulated athletic task. KAM increases strain to the ACL under clinically representative loading. Additionally, this work establishes the biomechanical characteristics of knee loading between sexes.

  11. Experimental impact cratering provides ground truth data for understanding planetary-scale collision processes

    NASA Astrophysics Data System (ADS)

    Poelchau, Michael H.; Deutsch, Alex; Kenkmann, Thomas

    2013-04-01

    Impact cratering is generally accepted as one of the primary processes that shape planetary surfaces in the solar system. While post-impact analysis of craters by remote sensing or field work gives many insights into this process, impact cratering experiments have several advantages for impact research: 1) excavation and ejection processes can be directly observed, 2) physical parameters of the experiment are defined and can be varied, and 3) cratered target material can be analyzed post-impact in an unaltered, uneroded state. The main goal of the MEMIN project is to comprehensively quantify impact processes by conducting a stringently controlled experimental impact cratering campaign on the meso-scale with a multidisciplinary analytical approach. As a unique feature we use two-stage light gas guns capable of producing impact craters in the decimeter size-range in solid rocks that, in turn, allow detailed spatial analysis of petrophysical, structural, and geochemical changes in target rocks and ejecta. In total, we have carried out 24 experiments at the facilities of the Fraunhofer EMI, Freiburg - Germany. Steel, aluminum, and iron meteorite projectiles ranging in diameter from 2.5 to 12 mm were accelerated to velocities ranging from 2.5 to 7.8 km/s. Targets were solid rocks, namely sandstone, quartzite and tuff that were either dry or saturated with water. In the experimental setup, high speed framing cameras monitored the impact process, ultrasound sensors were attached to the target to record the passage of the shock wave, and special particle catchers were positioned opposite of the target surface to capture the ejected target and projectile material. In addition to the cratering experiments, planar shock recovery experiments were performed on the target material, and numerical models of the cratering process were developed. The experiments resulted in craters with diameters up to 40 cm, which is unique in laboratory cratering research. Target porosity exponentially reduces crater volumes and cratering efficiency relative to non-porous rocks, and also yields less steep ejecta angles. Microstructural analysis of the subsurface shows a zone of pervasive grain crushing and pore space reduction. This is in good agreement with new mesoscale numerical models, which are able to quantify localized shock pressure behavior in the target's pore space. Planar shock recovery experiments confirm these local pressure excursions, based on microanalysis of shock metamorphic features in quartz. Saturation of porous target rocks with water counteracts many of the effects of porosity. Post-impact analysis of projectile remnants shows that during mixing of projectile and target melts, the Fe of the projectile is preferentially partitioned into target melt to a greater degree than Ni and Co. We plan to continue evaluating the experimental results in combination with numerical models. These models help to quantify and evaluate cratering processes, while experimental data serve as benchmarks to validate the improved numerical models, thus helping to "bridge the gap" between experiments and nature. The results confirm and expand current crater scaling laws, and make an application to craters on planetary surfaces possible.

  12. Impact of an Institutional Merger on Four Internal Stakeholder Groups of a College of Business?

    ERIC Educational Resources Information Center

    Williams, Henry; Feldman, Lori; Conners, Susan

    2017-01-01

    This paper compares the pre- and post-impact of a merger of two regional campuses in a statewide university system on its students, faculty, administrative, and professional support staff. Specifically, it looks at stakeholder impacts of the merger of the two Colleges of Business on these regional campuses into one entity. The second year of a…

  13. Development of a Meso-Scale Material Model for Ballistic Fabric and Its Use in Flexible-Armor Protection Systems

    DTIC Science & Technology

    2010-02-01

    s mobility. Early materials used included leather , silk, metal chain mail, and metal plates. Replacement of metal with a nylon (poly-amide) fabric...tests of flexible-fabric armor, and as shown by Tan et al. (Ref 24) in a series of postimpact fabric-inspection studies, play an important role in

  14. Assessing Spectral Evidence of Aqueous Activity in Two Putative Martian Paleolakes

    NASA Technical Reports Server (NTRS)

    Roush, Ted L.; Marzo, Giuseppe A.; Fonti, Sergio; Orofino, Vicenzo; Blanco, Armando; Gross, Christoph; Wendt, Lorenz

    2011-01-01

    We evaluate the evidence for the presence of mineral spectral signatures indicative of the past presence of water at two putative paleolakes on Mars using observations by the Mars Reconnaissance Orbiter (MRO) Compact Reconnaissance Image Spectrometer for Mars (CRISM). CRISM spectra of both sites are consistent with laboratory spectra of Mg-rich phyllosilicates. Our analysis represents the first detailed evaluation of these locations. The spatial occurrence and association with topographic features within the craters is distinctly different for the two sites. The occurrence of these minerals supports the conclusion that water was once active in the areas sampled by these craters. The distribution of the phyllosilicates in Luqa does not provide distinctive evidence for the presence of a previous standing body of water and is consistent with either impact emplacement or post-impact alteration. For Cankuzo, the phyllosilicate distribution provides evidence of a layer in the crater wall indicative of aqueous activity, but does not require a paleolake.

  15. Secular resonances with Ceres and Vesta

    NASA Astrophysics Data System (ADS)

    Tsirvoulis, Georgios; Novaković, Bojan

    2016-12-01

    In this work we explore dynamical perturbations induced by the massive asteroids Ceres and Vesta on main-belt asteroids through secular resonances. First we determine the location of the linear secular resonances with Ceres and Vesta in the main belt, using a purely numerical technique. Then we use a set of numerical simulations of fictitious asteroids to investigate the importance of these secular resonances in the orbital evolution of main-belt asteroids. We found, evaluating the magnitude of the perturbations in the proper elements of the test particles, that in some cases the strength of these secular resonances is comparable to that of known non-linear secular resonances with the giant planets. Finally we explore the asteroid families that are crossed by the secular resonances we studied, and identified several cases where the latter seem to play an important role in their post-impact evolution.

  16. Analysis of Long Bone and Vertebral Failure Patterns.

    DTIC Science & Technology

    1982-09-30

    processes further supported the findings of • :the scanning electron microscopy studies . In the impacted animals, the cartilage surface was eroded... cartilage matrix. In the six years post-impaction group, the articular cartilage had converted to fibrocartilage instead of normal hyaline cartilage . The...columns of four rhesus monkeys have been collected and are being processed for study with light microscopy and scanning electron microscopy. The baboon

  17. Occupant injury and fatality in general aviation aircraft for which dynamic crash testing is certification-mandated.

    PubMed

    Boyd, Douglas D

    2015-06-01

    Towards further improving general aviation aircraft crashworthiness, multi-axis dynamic tests have been required for aircraft certification (14CFR23.562) since 1985. The objective of this study was to determine if occupants in aircraft certified to these higher crashworthiness standards show a mitigated fraction of fatal accidents and/or injury severity. The NTSB aviation database was queried for accidents occurring between 2002 and 2012 involving aircraft certified to, or immune from, dynamic crash testing and manufactured after 1999. Only operations conducted under 14CFR Part 91 were considered. Statistical analysis employed proportion tests and logistic regression. Off-airport landings are associated with high decelerative forces; however for off-airport landings, the fraction of fatal accidents for aircraft subject to, or exempt from, dynamic crash testing was similar (0.53 and 0.60, respectively). Unexpectedly, for on-airport landings a higher fraction of fatalities was evident for aircraft whose certification mandated dynamic crash testing. Improved crashworthiness standards would be expected to translate into a reduced severity of accident injuries. For all accidents, as well as for those deemed survivable, the fraction of minor and serious injuries was reduced for occupants in aircraft certified to the higher crashworthiness standards. Surprisingly, the fraction of occupants fatally injured was not decreased for aircraft subject to dynamic crash tests. To shed light on this unexpected finding flight history, airman demographics and post-impact fires for aircraft for which dynamic crash testing is mandatory or exempt was examined. For the former cohort the median distance of the accident flight was nearly 44% higher. Aircraft subject to dynamic crash testing were also involved in a greater fraction (0.25 versus 0.12, respectively) of post-impact fires. Our data suggest that while the more stringent crashworthiness standards have mitigated minor and serious injuries, surprisingly the fraction of occupants fatally injured is unaltered. The unchanged fraction of fatal injuries may reflect partly (a) fatigue associated with longer flight distances and (b) a greater proportion of post-impact fires. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Foreign Object Damage of Two Gas-Turbine Grade Silicon Nitrides in a Thin Disk Configuration

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Pereira, J. Michael; Janosik, Lesley A.; Bhatt, Ramakrishna T.

    2003-01-01

    Foreign object damage (FOD) behavior of two commercial gas-turbine grade silicon nitrides, AS800 and SN282, was determined at ambient temperature through post-impact strength testing for thin disks impacted by steel-ball projectiles with a diameter of 1.59 mm in a velocity range from 115 to 440 m/s. AS800 silicon nitride exhibited a greater FOD resistance than SN282, primarily due to its greater value of fracture toughness (K(sub IC)). The critical impact velocity in which the corresponding post-impact strength yielded the lowest value was V(sub c) approx. 440 and 300 m/s for AS800 and SN282, respectively. A unique lower-strength regime was typified for both silicon nitrides depending on impact velocity, attributed to significant radial cracking. The damages generated by projectile impact were typically in the forms of ring, radial, and cone cracks with their severity and combination being dependent on impact velocity. Unlike thick (3 mm) flexure bar specimens used in the previous studies, thin (2 mm) disk target specimens exhibited a unique backside radial cracking occurring on the reverse side just beneath the impact sites at and above impact velocity of 160 and 220 m/s for SN282 and AS800, respectively.

  19. Kamenetsk—A new impact structure in the Ukrainian Shield

    NASA Astrophysics Data System (ADS)

    Gurov, Eugene; Nikolaenko, Nikolay; Shevchuk, Helena; Yamnichenko, Anatoly

    2017-12-01

    The Kamenetsk impact structure is a deeply eroded simple crater that formed in crystalline rocks of the Ukrainian Shield. This study presents structural, lithologic, and shock metamorphic evidence for an impact origin of the Kamenetsk structure, which was previously described as a paleovolcano. The Kamenetsk structure is an oval depression that is 1.0-1.2 km in diameter and 130 m deep. The structure is deeply eroded, and only the lower part of the sequence of lithic breccia has been preserved in the deepest part of the crater to recent time, while the predominant part of impact rocks and postimpact sediments was eroded. Manifestations of shock metamorphism of minerals, especially planar deformation features in quartz and feldspars, were determined by petrographic investigations of lithic breccia that allowed us to determine the impact origin of the Kamenetsk structure. The erosion of the crater and surrounding target to a minimal depth of 220 m preceded the deposition of the postimpact sediments. The time of the formation of the Kamenetsk structure is bracketed within a wide interval from 2.0 to 2.1 Ga, the age of the crystalline target rocks, to the Late Miocene age of the sediments overlaying the crater. The deep erosion of the structure suggests it is probably Paleozoic in age.

  20. A chemostratigraphic method to determine the end of impact-related sedimentation at marine-target impact craters (Chesapeake Bay, Lockne, Tvären)

    USGS Publications Warehouse

    Ormö, Jens; Hill, Andrew C.; Self-Trail, Jean M.

    2010-01-01

    To better understand the impact cratering process and its environmental consequences at the local to global scale, it is important to know when in the geological record of an impact crater the impact-related processes cease. In many instances, this occurs with the end of early crater modification, leaving an obvious sedimentological boundary between impactites and secular sediments. However, in marine-target craters the transition from early crater collapse (i.e., water resurge) to postimpact sedimentation can appear gradual. With the a priori assumption that the reworked target materials of the resurge deposits have a different chemical composition to the secular sediments we use chemostratigraphy (δ13Ccarb, %Corg, major elements) of sediments from the Chesapeake Bay, Lockne, and Tvären craters, to define this boundary. We show that the end of impact-related sedimentation in these cases is fairly rapid, and does not necessarily coincide with a visual boundary (e.g., grain size shift). Therefore, in some cases, the boundary is more precisely determined by chemostratigraphy, especially carbonate carbon isotope variations, rather than by visual inspection. It is also shown how chemostratigraphy can confirm the age of marine-target craters that were previously determined by biostratigraphy; by comparing postimpact carbon isotope trends with established regional trends.

  1. Foraminiferal repopulation of the late Eocene Chesapeake Bay impact crater

    USGS Publications Warehouse

    Poag, C. Wylie

    2012-01-01

    The Chickahominy Formation is the initial postimpact deposit in the 85km-diameter Chesapeake Bay impact crater, which is centered under the town of Cape Charles, Virginia, USA. The formation comprises dominantly microfossil-rich, silty, marine clay, which accumulated during the final ~1.6myr of late Eocene time. At cored sites, the Chickahominy Formation is 16.8-93.7m thick, and fills a series of small troughs and subbasins, which subdivide the larger Chickahominy basin. Nine coreholes drilled through the Chickahominy Formation (five inside the crater, two near the crater margin, and two ~3km outside the crater) record the stratigraphic and paleoecologic succession of 301 indigenous species of benthic foraminifera, as well as associated planktonic foraminifera and bolboformids. Two hundred twenty of these benthic species are described herein, and illustrated with scanning electron photomicrographs. Absence of key planktonic foraminiferal and Bolboforma species in early Chickahominy sediments indicates that detrimental effects of the impact also disturbed the upper oceanic water column for at least 80-100kyr postimpact. After an average of ~73kyr of stressed, rapidly fluctuating paleoenvironments, which were destabilized by after-effects of the impact, most of the cored Chickahominy subbasins maintained stable, nutrient-rich, low-oxygen bottom waters and interstitial microhabitats for the remaining ~1.3myr of late Eocene time.

  2. A Review of General Aviation Safety (1984-2017).

    PubMed

    Boyd, Douglas D

    2017-07-01

    General aviation includes all civilian aviation apart from operations involving paid passenger transport. Unfortunately, this category of aviation holds a lackluster safety record, accounting for 94% of civil aviation fatalities. In 2014, of 1143 general aviation accidents, 20% were fatal compared with 0 of 29 airline mishaps in the United States. Herein, research findings over the past 30 yr will be reviewed. Accident risk factors (e.g., adverse weather, geographical region, post-impact fire, gender differences) will be discussed. The review will also summarize the development and implementation of stringent crashworthiness designs with multi-axis dynamic testing and head-injury protection and its impact on mitigating occupant injury severity. The benefits and drawbacks of new technology and human factor considerations associated with increased general aviation automation will be debated. Data on the safety of the aging general aviation population and increased drug usage will also be described. Finally, areas in which general aviation occupant survival could be improved and injury severity mitigated will be discussed with the view of equipping aircraft with 1) crash-resistant fuel tanks to reduce post-impact conflagration; 2) after-market ballistic parachutes for older aircraft; and 3) current generation electronic locator beacons to hasten site access by first responders.Boyd DD. A review of general aviation safety (1984-2017). Aerosp Med Hum Perform. 2017; 88(7):657-664.

  3. Postimpact heat conduction and compaction-driven fluid flow in the Chesapeake Bay impact structure based on downhole vitrinite reflectance data, ICDP-USGS Eyreville deep core holes and Cape Charles test holes

    USGS Publications Warehouse

    Malinconico, M.L.; Sanford, W.E.; Wright, Horton W.J.J.

    2009-01-01

    Vitrinite reflectance data from the International Continental Scientific Drilling Program (ICDP)-U.S. Geological Survey (USGS) Eyreville deep cores in the centralcrater moat of the Chesapeake Bay impact structure and the Cape Charles test holes on the central uplift show patterns of postimpact maximum-temperature distribution that result from a combination of conductive and advective heat flow. Within the crater-fill sediment-clast breccia sequence at Eyreville, an isoreflectance (-0.44% Ro) section (525-1096 m depth) is higher than modeled background coastal-plain maturity and shows a pattern typical of advective fluid flow. Below an intervening granite slab, a short interval of sediment-clast breccia (1371-1397 m) shows a sharp increase in reflectance (0.47%-0.91% Ro) caused by conductive heat from the underlying suevite (1397-1474 m). Refl ectance data in the uppermost suevite range from 1.2% to 2.1% Ro. However, heat conduction alone is not sufficient to affect the temperature of sediments more than 100 m above the suevite. Thermal modeling of the Eyreville suevite as a 390 ??C cooling sill-like hot rock layer supplemented by compaction- driven vertical fluid flow (0.046 m/a) of cooling suevitic fluids and deeper basement brines (120 ??C) upward through the sediment breccias closely reproduces the measured reflectance data. This scenario would also replace any marine water trapped in the crater fill with more saline brine, similar to that currently in the crater, and it would produce temperatures sufficient to kill microbes in sediment breccias within 450 m above the synimsuevite. A similar downhole maturity pattern is present in the sediment-clast breccia over the central uplift. High-reflectance (5%-9%) black shale and siltstone clasts in the suevite and sediment-clast breccia record a pre-impact (Paleozoic?) metamorphic event. Previously published maturity data in the annular trough indicate no thermal effect there from impact-related processes. ?? 2009 The Geological Society of America.

  4. Chicxulub: testing for post-impact hydrothermal inputs into the Tertiary ocean

    NASA Astrophysics Data System (ADS)

    Rowe, A.; Wilkinson, J.; Morgan, J.

    2003-04-01

    Large terrestrial impacts produce intense fracturing of the crust and large melt sheets, providing ideal conditions for extensive hydrothermal circulation. In marine settings, such as Chicxulub, there is the potential for downward penetration of cold seawater, heating by the thermal anomaly at the impact site and leaching of metals, prior to buoyancy driven flow back to the surface. There, fluids may undergo venting into the water column. A large proportion of the metals in such vent fluids precipitate close to the site of discharge; however, a proportion of the fluid is dispersed as a hydrothermal plume. Dissolved and particulate materials (in particular manganese and iron oxyhydroxides) can be carried for several hundreds of kilometers, before falling out to form metal-rich sediments. A series of Tertiary core samples has been obtained from the International Continental Drilling Program at Chicxulub (CSDP). These comprise fine-grained cream coloured carbonate sediments with fine laminations. Transmitted light and cathodoluminescence petrography have been used to carry out a preliminary characterization of the samples. Multi-element analysis has also been undertaken by ICP-AES. Samples were reduced to powder and digested using a nitric-perchloric-hydrofluoric acid attack. Rare earth elements (REE) have been analysed by ICP-MS and solutions were prepared using a modified nitric-perchloric-hydrofluoric acid attack. Geochemical analyses have been carried out to test for characteristic signals of hydrothermal input, such as enrichments in Mn, Fe, Cu, Zn, Pb, Mg, Ba, Co, Cr and Ni. The REE are scavenged from seawater onto iron oxide surfaces in the plume; hence anomalous REE concentrations are also indicative of hydrothermal addition. Furthermore, the type of anomaly can differentiate between sediments proximal (+ve Eu) distal (-ve Ce) to the vent site. The stratigraphic extent of any anomalies can be used to constrain the duration of any post-impact circulation. The wider significance of such hydrothermal circulation, if identified, include the potential formation of hydrothermal mineralization and vent-related ecosystems in the Chicxulub crater. The results will also have implications for the exploration of impact-related hydrothermal ecosystems on other planets.

  5. Uppermost impact fallback layer in the Bosumtwi crater (Ghana): Mineralogy, geochemistry, and comparison with Ivory Coast tektites

    NASA Astrophysics Data System (ADS)

    Koeberl, Christian; Brandstätter, Franz; Glass, Billy P.; Hecht, Lutz; Mader, Dieter; Reimold, Wolf Uwe

    In 2004, an International Continental Scientific Drilling Program (ICDP) drilling project at the Bosumtwi impact crater, Ghana (10.5 km in diameter, 1.07 Myr old), was performed to study the sediments that fill the lake as well as the underlying impactites. In one (LB-05) of 16 cores drilled into the lake sediments, the zone between the impact breccias and the post-impact sediments was penetrated, preserving the final, fine-grained impact fallback layer. This ~30 cm thick layer contains in the top 10 cm “accretionary” lapilli, microtektite-like glass spherules, and shocked quartz grains. Glass particles -- mostly of splash form less than 1 mm size -- make up the bulk of the grains (~70-78% by number) in the coarser size fraction (>125 μm) of the top of the fallback layer. About one-third of all quartz grains in the uppermost part of the layer are shocked, with planar deformation features (PDFs); almost half of these grains are highly shocked, with 3 or more sets of PDFs. K-feldspar grains also occur and some show shock deformation. The abundance of shocked quartz grains and the average shock level as indicated by the number of sets of PDFs, for both quartz and K-feldspar, decrease with depth into the layer. The well-preserved glass spherules and fragments are chemically rather homogeneous within each particle, and also show relatively small variations between the various particles. On average, the composition of the fallback spherules from core LB-5B is very similar to the composition of Ivory Coast tektites and microtektites, with the exception of CaO contents, which are about 1.5 to 2 times higher in the fallback spherules. This is a rare case in which the uppermost fallback layer and the transition to the post-impact sediments has been preserved in an impact structure; its presence indicates that the impactite sequence at Bosumtwi is complete and that Bosumtwi is a very well-preserved impact crater.

  6. Damage Behaviors and Compressive Strength of Toughened CFRP Laminates with Thin Plies Subjected to Transverse Impact Loadings

    NASA Astrophysics Data System (ADS)

    Yokozeki, Tomohiro; Aoki, Yuichiro; Ogasawara, Toshio

    It has been recognized that damage resistance and strength properties of CFRP laminates can be improved by using thin-ply prepregs. This study investigates the damage behaviors and compressive strength of CFRP laminates using thin-ply and standard prepregs subjected to out-of-plane impact loadings. CFRP laminates used for the evaluation are prepared using the standard prepregs, thin-ply prepregs, and combinations of the both. Weight-drop impact test and post-impact compression test of quasi-isotropic laminates are performed. It is shown that the damage behaviors are different between the thin-ply and the standard laminates, and the compression-after-impact strength is improved by using thin-ply prepregs. Effects of the use of thin-ply prepregs and the layout of thin-ply layers on the damage behaviors and compression-after-impact properties are discussed based on the experimental results.

  7. Hopane Biomarkers Traced from Bedrock to Recent Sediments and Ice at the Haughton Impact Structure, Devon Island: Implications for the Search for Biomarkers on Mars

    NASA Technical Reports Server (NTRS)

    Parnell, J.; Osinski, G. R.; Lee, P.; Cockell, C. C.; Taylor, C. W.

    2004-01-01

    Hopanoid biomarkers have been successsfully traced from Palaeozoic target bedrock to Miocene impact-processed rocks, post-impact sediments, and Qu aternary ice at the Haughton impact Structure, Devon Island, High Arctic, suggesting that similar biomarkers and techniques to detect them might provide a promising strategy in the search for biomarkers in rocks, sediments and ice on Mars.

  8. Research core drilling in the Manson impact structure, Iowa

    NASA Technical Reports Server (NTRS)

    Anderson, R. R.; Hartung, J. B.; Roddy, D. J.; Shoemaker, E. M.

    1992-01-01

    The Manson impact structure (MIS) has a diameter of 35 km and is the largest confirmed impact structure in the United States. The MIS has yielded a Ar-40/Ar-39 age of 65.7 Ma on microcline from its central peak, an age that is indistinguishable from the age of the Cretaceous-Tertiary boundary. In the summer of 1991 the Iowa Geological Survey Bureau and U.S. Geological Survey initiated a research core drilling project on the MIS. The first core was beneath 55 m of glacial drift. The core penetrated a 6-m layered sequence of shale and siltstone and 42 m of Cretaceous shale-dominated sedimentary clast breccia. Below this breccia, the core encountered two crystalline rock clast breccia units. The upper unit is 53 m thick, with a glassy matrix displaying various degrees of devitrification. The upper half of this unit is dominated by the glassy matrix, with shock-deformed mineral grains (especially quartz) the most common clast. The glassy-matrix unit grades downward into the basal unit in the core, a crystalline rock breccia with a sandy matrix, the matrix dominated by igneous and metamorphic rock fragments or disaggregated grains from those rocks. The unit is about 45 m thick, and grains display abundant shock deformation features. Preliminary interpretations suggest that the crystalline rock breccias are the transient crater floor, lifted up with the central peak. The sedimentary clast breccia probably represents a postimpact debris flow from the crater rim, and the uppermost layered unit probably represents a large block associated with the flow. The second core (M-2) was drilled near the center of the crater moat in an area where an early crater model suggested the presence of postimpact lake sediments. The core encountered 39 m of sedimentary clast breccia, similar to that in the M-1 core. Beneath the breccia, 120 m of poorly consolidated, mildly deformed, and sheared siltstone, shale, and sandstone was encountered. The basal unit in the core was another sequence of sedimentary clast breccia. The two sedimentary clast units, like the lithologically similar unit in the M-1 core, probably formed as debris flows from the crater rim. The middle, nonbrecciated interval is probably a large, intact block of Upper Cretaceous strata transported from the crater rim with the debris flow. Alternatively, the sequence may represent the elusive postimpact lake sequence.

  9. Ecological response to collapse of the biological pump following the mass extinction at the Cretaceous-Paleogene boundary

    NASA Astrophysics Data System (ADS)

    Vellekoop, Johan; Woelders, Lineke; Açikalin, Sanem; Smit, Jan; van de Schootbrugge, Bas; Yilmaz, Ismail Ö.; Brinkhuis, Henk; Speijer, Robert P.

    2017-02-01

    It is commonly accepted that the mass extinction associated with the Cretaceous-Paleogene (K-Pg) boundary (˜ 66 Ma) is related to the environmental effects of a large extraterrestrial impact. The biological and oceanographic consequences of the mass extinction are, however, still poorly understood. According to the Living Ocean model, the biological crisis at the K-Pg boundary resulted in a long-term reduction of export productivity in the early Paleocene. Here, we combine organic-walled dinoflagellate cyst (dinocyst) and benthic foraminiferal analyses to provide new insights into changes in the coupling of pelagic and benthic ecosystems. To this end, we perform dinocyst and benthic foraminiferal analyses on the recently discovered Tethyan K-Pg boundary section at Okçular, Turkey, and compare the results with other K-Pg boundary sites in the Tethys. The post-impact dominance of epibenthic morphotypes and an increase of inferred heterotrophic dinocysts in the early Paleocene at Okçular are consistent with published records from other western Tethyan sites. Together, these records indicate that during the early Paleocene more nutrients remained available for the Tethyan planktonic community, whereas benthic communities were deprived of food. Hence, in the post-impact phase the reduction of export productivity likely resulted in enhanced recycling of nutrients in the upper part of the water column, all along the western Tethyan margins.

  10. Foreign Object Damage in Disks of Two Gas-turbine-grade Silicon Nitrides by Steel Ball Projectiles at Ambient Temperature

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Pereira, J. Michael; Janosik, Lesley A.; Bhatt, Ramakrishna T.

    2003-01-01

    Foreign object damage (FOD) behavior of two commercial gas-turbine-grade silicon nitrides, AS800 and SN282, was determined at ambient temperature through postimpact strength testing of disks impacted by steel ball projectiles with a diameter of 1.59 mm in a velocity range from 115 to 440 m/s. AS800 silicon nitride exhibited a greater FOD resistance than SN282, primarily due to its greater value of fracture toughness (k(sub Ic)). The critical impact velocity V(sub c) for which the corresponding postimpact strength was the lowest was V(sub c) approximately equal to 440 and 300 m/s AS800 and SN282, respectively. A unique lower strength regime was typified for both silicon nitrides depending on impact velocity and was attributed to significant radial cracking. The damage generated by projectile impact was typically in the form of ring, radial, and cone cracks with their severity and combination being dependent on impact velocity. Unlike the thick (4 millimeters) flexure bar specimens used in our previous studies, the thin (2 millimeter) disk target specimen exhibited a unique back-side radial cracking on the reverse side just beneath the impact sites at and above impact velocities of 160 meters per second for SN282 and 220 meters per second AS800.

  11. A Multi-Level Decision Fusion Strategy for Condition Based Maintenance of Composite Structures

    PubMed Central

    Sharif Khodaei, Zahra; Aliabadi, M.H.

    2016-01-01

    In this work, a multi-level decision fusion strategy is proposed which weighs the Value of Information (VoI) against the intended functions of a Structural Health Monitoring (SHM) system. This paper presents a multi-level approach for three different maintenance strategies in which the performance of the SHM systems is evaluated against its intended functions. Level 1 diagnosis results in damage existence with minimum sensors covering a large area by finding the maximum energy difference for the guided waves propagating in pristine structure and the post-impact state; Level 2 diagnosis provides damage detection and approximate localization using an approach based on Electro-Mechanical Impedance (EMI) measures, while Level 3 characterizes damage (exact location and size) in addition to its detection by utilising a Weighted Energy Arrival Method (WEAM). The proposed multi-level strategy is verified and validated experimentally by detection of Barely Visible Impact Damage (BVID) on a curved composite fuselage panel. PMID:28773910

  12. Paleomagnetic and Magnetostratigraphic Studies in Drilling Projects of Impact Craters - Recent Studies, Challenges and Perspectives

    NASA Astrophysics Data System (ADS)

    Fucugauchi, J. U.; Velasco-Villarreal, M.; Perez-Cruz, L. L.

    2013-05-01

    Paleomagnetic studies have long been successfully carried out in drilling projects, to characterize the borehole columns and to investigate the subsurface structure and stratigraphy. Magnetic susceptibility logging and magnetostratigraphic studies provide data for lateral correlation, formation evaluation, azimuthal core orientation, physical properties, etc., and are part of the tools available in the ocean and continental drilling programs. The inclusion of continuous core recovery in scientific drilling projects have greatly expanded the range of potential applications of paleomagnetic and rock magnetic studies, by allowing laboratory measurements on core samples. For this presentation, we concentrate on drilling studies of impact structures and their usefulness for documenting the structure, stratigraphy and physical properties at depth. There are about 170-180 impact craters documented in the terrestrial record, which is a small number compared to what is observed in the Moon, Mars, Venus and other bodies of the solar system. Of the terrestrial impact craters, only a few have been studied by drilling. Some craters have been drilled as part of industry exploration surveys and/or academic projects, including notably the Sudbury, Ries, Vredefort, Manson and many other craters. As part of the Continental ICDP program, drilling projects have been conducted on the Chicxulub, Bosumtwi, Chesapeake and El gygytgyn craters. Drilling of terrestrial craters has proved important in documenting the shallow stratigraphy and structure, providing insight on the cratering and impact dynamics. Questions include several that can only be addressed by retrieving core samples and laboratory analyses. Paleomagnetic, rock magnetic and fabric studies have been conducted in the various craters, which are here summarized with emphasis on the Chicxulub crater and Yucatan carbonate platform. Chicxulub is buried under a kilometer of younger sediments, making drilling an essential tool. Oil exploration included several boreholes, and additionally we have drilled 11 boreholes with continuous core recovery. Contributions and limitations of paleomagnetism for investigating the impact age, crater stratigraphy, cratering, ejecta emplacement, impact dynamics, hydrothermal system and post-impact processes are discussed.

  13. Pore-water chemistry from the ICDP-USGS coer hole in the Chesapeake Bay impact structure--Implications for paleohydrology, microbial habitat, and water resources

    USGS Publications Warehouse

    Sanford, Ward E.; Voytek, Mary A.; Powars, David S.; Jones, Blair F.; Cozzarelli, Isabelle M.; Eganhouse, Robert P.; Cockell, Charles S.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between fresh and saline water from 100 to 500 m depth in the post-impact sediment section, and an underlying syn-impact section that is almost entirely filled with brine. The presence of brine in the lowermost post-impact section and the trend in the dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting its occurrence may be common in the inner crater. However, groundwater flow conditions in the structure may reduce the salt-water-intrusion hazard associated with the brine.

  14. Impact-Induced Clay Mineral Formation and Distribution on Mars

    NASA Technical Reports Server (NTRS)

    Rivera-Valentin, E. G.; Craig, P. I.

    2015-01-01

    Clay minerals have been identified in the central peaks and ejecta blankets of impact craters on Mars. Several studies have suggested these clay minerals formed as a result of impact induced hydrothermalism either during Mars' Noachian era or more recently by the melting of subsurface ice. Examples of post-impact clay formation is found in several locations on Earth such as the Mjolnir and Woodleigh Impact Structures. Additionally, a recent study has suggested the clay minerals observed on Ceres are the result of impact-induced hydrothermal processes. Such processes may have occurred on Mars, possibly during the Noachian. Distinguishing between clay minerals formed preor post-impact can be accomplished by studying their IR spectra. In fact, showed that the IR spectra of clay minerals is greatly affected at longer wavelengths (i.e. mid-IR, 5-25 micron) by impact-induced shock deformation while the near-IR spectra (1.0-2.5 micron) remains relatively unchanged. This explains the discrepancy between NIR and MIR observations of clay minerals in martian impact craters noted. Thus, it allows us to determine whether a clay mineral formed from impact-induced hydrothermalism or were pre-existing and were altered by the impact. Here we study the role of impacts on the formation and distribution of clay minerals on Mars via a fully 3-D Monte Carlo cratering model, including impact- melt production using results from modern hydrocode simulations. We identify regions that are conducive to clay formation and the location of clay minerals post-bombardment.

  15. Ichnofabrics and Facies in the Paleocene of Chicxulub: A Record of the Recovery of Life Post-Impact

    NASA Astrophysics Data System (ADS)

    Whalen, M. T.; O'Malley, K.; Lowery, C. M.; Rodriguez-Tovar, F. J.; Gulick, S. P. S.; Morgan, J. V.

    2017-12-01

    IODP/ICDP Expedition 364 recovered 829 m of core at Site M0077 including 110 m of post-impact, (hemi)pelagic Paleogene sedimentary rocks overlying the Chicxulub impact crater peak ring formed from suevite, melt rock, and granitic basement. The transition between suevite and Paleocene limestone (Unit 1F) is a remarkable fining upward package of gravel to sand-sized suevite (Unit 2A) overlain by the laminated carbonate-rich Unit 1G that records deposition of fine-grained material post-impact and contains a mix of Late Cretaceous and earliest Danian taxa. This study concentrates on the overlying Unit 1F. The ichnofabric index (ii, 1-6 indicating no bioturbation to complete homogenization), provides a semiquantitative estimate of burrow density to help assess the return of life to the crater. Unit 1F is 10 m thick with a sharp contact at the base of a green claystone (ii 2) that overlies Unit 1G. It consists of cm-dm interbedded blue-gray marlstone (ii 2) grading upward into gray to blue-gray wacke/packstone (ii 3-5). Contacts between facies are mostly gradational due to burrowing. The upper 3 m of the unit is a yellow-brown burrowed packstone (ii 4) intercalated with gray marlstone (ii 2). The uppermost 7.5 cm is calcite cemented with 1 cm wide burrows (ii 3-4) and fine to coarse sand size clasts including foraminifera. The upper surface of the unit is a hardground with an 2 Myr unconformity overlain by Eocene rocks. The first well-defined burrows occur in the upper 30 cm of Unit 1G. Unequivocal burrows (ii 2) that disturb sedimentary facies occur in overlying Unit 1F with values of 3-5 recorded in the overlying 10 cm indicating significant disruption of primary sedimentary structures. The iis in Unit 1F vary between 2 and 5 with rare laminated intervals without bioturbation (ii 1). Values of ii correlate well with facies changes, i.e. marlstones display lower iis than more carbonate-rich facies, implying a depth and/or redox control on burrower distribution. The ii data indicate that burrowers were re-established in the crater before the end of deposition of Unit 1G. The lowest Danian zone Pα is documented in the lowermost part of Unit 1F. Trace makers were thus active by the earliest Danian with an increase in abundance and diversity during the lower Danian, indicating a rapid and continuous return of benthic life to the crater.

  16. Weathering of post-impact hydrothermal deposits from the Haughton impact structure: implications for microbial colonization and biosignature preservation.

    PubMed

    Izawa, M R M; Banerjee, Neil R; Osinski, G R; Flemming, R L; Parnell, J; Cockell, C S

    2011-01-01

    Meteorite impacts are among the very few processes common to all planetary bodies with solid surfaces. Among the effects of impact on water-bearing targets is the formation of post-impact hydrothermal systems and associated mineral deposits. The Haughton impact structure (Devon Island, Nunavut, Canada, 75.2 °N, 89.5 °W) hosts a variety of hydrothermal mineral deposits that preserve assemblages of primary hydrothermal minerals commonly associated with secondary oxidative/hydrous weathering products. Hydrothermal mineral deposits at Haughton include intra-breccia calcite-marcasite vugs, small intra-breccia calcite or quartz vugs, intra-breccia gypsum megacryst vugs, hydrothermal pipe structures and associated surface "gossans," banded Fe-oxyhydroxide deposits, and calcite and quartz veins and coatings in shattered target rocks. Of particular importance are sulfide-rich deposits and their associated assemblage of weathering products. Hydrothermal mineral assemblages were characterized structurally, texturally, and geochemically with X-ray diffraction, micro X-ray diffraction, optical and electron microscopy, and inductively coupled plasma atomic emission spectroscopy. Primary sulfides (marcasite and pyrite) are commonly associated with alteration minerals, including jarosite (K,Na,H(3)O)Fe(3)(SO(4))(2)(OH)(6), rozenite FeSO(4)·4(H(2)O), copiapite (Fe,Mg)Fe(4)(SO(4))(6)(OH)(2)·20(H(2)O), fibroferrite Fe(SO(4))(OH)·5(H(2)O), melanterite FeSO(4)·7(H(2)O), szomolnokite FeSO(4)·H(2)O, goethite α-FeO(OH), lepidocrocite γ-FeO(OH) and ferrihydrite Fe(2)O(3)·0.5(H(2)O). These alteration assemblages are consistent with geochemical conditions that were locally very different from the predominantly circumneutral, carbonate-buffered environment at Haughton. Mineral assemblages associated with primary hydrothermal activity, and the weathering products of such deposits, provide constraints on possible microbial activity in the post-impact environment. The initial period of active hydrothermal circulation produced primary mineral assemblages, including Fe sulfides, and was succeeded by a period dominated by oxidation and low-temperature hydration of primary minerals by surface waters. Active hydrothermal circulation can enable the rapid delivery of nutrients to microbes. Nutrient availability following the cessation of hydrothermal circulation is likely more restricted; therefore, the biological importance of chemical energy from hydrothermal mineral deposits increases with time. Weathering of primary hydrothermal deposits and dissolution and reprecipitation of mobile weathering products also create many potential habitats for endolithic microbes. They also provide a mechanism that may preserve biological materials, potentially over geological timescales. © Mary Ann Liebert, Inc.

  17. Opportunity In Situ Geologic Context of Aqueous Alteration Along Offsets in the Rim of Endeavour Crater

    NASA Technical Reports Server (NTRS)

    Crumpler, L. S.; Arvidson, R. E.; Farrand, W. H.; Golombek, M. P.; Grant, J. A.; Ming, D. W.; Mittlefehldt, D. W.; Parker, T. J.

    2015-01-01

    Mars Exploration Rover Opportunity traversed 7.9 km and 27 degrees of arc along the rim of the 22 km-diameter Noachian "Endeavour" impact crater since its arrival 1200 sols ago. Areas of aqueous and low-grade thermal alteration, and changes in structure, attitude, and macroscopic texture of outcrops are notable across several discontinuities between segments of the crater rim. The discontinuities and other post-impact joints and fractures coincide with sites of apparent deep fluid circulation processes responsible for thermal and chemical alteration of local outcrops.

  18. Pore-water chemistry from the ICDP-USGS core hole in the Chesapeake Bay impact structure-Implications for paleohydrology, microbial habitat, and water resources

    USGS Publications Warehouse

    Sanford, W.E.; Voytek, M.A.; Powars, D.S.; Jones, B.F.; Cozzarelli, I.M.; Cockell, C.S.; Eganhouse, R.P.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between freshwater and saline water from 100 to 500 m depth in the postimpact sediment section, and an underlying synimpact section that is almost entirely filled with brine. The presence of brine in the lowermost postimpact section and the trend in dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting that its occurrence may be common in the inner crater. However, groundwater-flow conditions in the structure may reduce the saltwater-intrusion hazard associated with the brine. ?? 2009 The Geological Society of America.

  19. Effects of Constituents and Lay-up Configuration on Drop-Weight Tests of Fiber-Metal Laminates

    NASA Astrophysics Data System (ADS)

    Liu, Yanxiong; Liaw, Benjamin

    2010-02-01

    Impact responses and damage of various fiber-metal laminates were studied using a drop-weight instrument with the post-impact damage characteristics being evaluated through ultrasonic and mechanical sectioning techniques. The first severe failure induced by the low-velocity drop-weight impact occurred as delamination between the aluminum and fiber-epoxy layers at the non-impact side. It was followed by a visible shear crack in the outer aluminum layer on the non-impact face. Through-thickness shear cracks in the aluminum sheets and severe damage in the fiber laminated layers (including delamination between adjacent fiber-epoxy laminae with different fiber orientations) developed under higher energy impacts. The impact properties of fiber-metal laminates varied with different constituent materials and fiber orientations. Since it was punched through easily, the aramid-fiber reinforced fiber-metal laminates (ARALL) offered poorer impact resistance than the glass-fiber reinforced fiber-metal laminates (GLARE). Tougher and more ductile aluminum alloys improved the impact resistance. GLARE made of cross-ply prepregs provided better impact resistance than GLARE with unidirectional plies.

  20. Stardust impact analogs: Resolving pre- and postimpact mineralogy in Stardust Al foils

    NASA Astrophysics Data System (ADS)

    Wozniakiewicz, Penelope J.; Ishii, Hope A.; Kearsley, Anton T.; Burchell, Mark J.; Bradley, John P.; Price, Mark C.; Teslich, Nick; Lee, Martin R.; Cole, Mike J.

    2012-04-01

    The grains returned by NASA's Stardust mission from comet 81P/Wild 2 represent a valuable sample set that is significantly advancing our understanding of small solar system bodies. However, the grains were captured via impact at ˜6.1 km s-1 and have experienced pressures and temperatures that caused alteration. To ensure correct interpretations of comet 81P/Wild 2 mineralogy, and therefore preaccretional or parent body processes, an understanding of the effects of capture is required. Using a two-stage light-gas gun, we recreated Stardust encounter conditions and generated a series of impact analogs for a range of minerals of cometary relevance into flight spare Al foils. Through analyses of both preimpact projectiles and postimpact analogs by transmission electron microscopy, we explore the impact processes occurring during capture and distinguish between those materials inherent to the impactor and those that are the product of capture. We review existing and present additional data on olivine, diopside, pyrrhotite, and pentlandite. We find that surviving crystalline material is observed in most single grain impactor residues. However, none is found in that of a relatively monodisperse aggregate. A variety of impact-generated components are observed in all samples. Al incorporation into melt-derived phases allows differentiation between melt and shock-induced phases. In single grain impactor residues, impact-generated phases largely retain original (nonvolatile) major element ratios. We conclude that both surviving and impact-generated phases in residues of single grain impactors provide valuable information regarding the mineralogy of the impacting grain whilst further studies are required to fully understand aggregate impacts and the role of subgrain interactions during impact.

  1. Frequency of Head-Impact–Related Outcomes by Position in NCAA Division I Collegiate Football Players

    PubMed Central

    Kiernan, Patrick T.; Kroshus, Emily; Daneshvar, Daniel H.; Montenigro, Philip H.; McKee, Ann C.; Stern, Robert A.

    2015-01-01

    Abstract Concussions and subconcussive impacts sustained in American football have been associated with short- and long-term neurological impairment, but differences in head impact outcomes across playing positions are not well understood. The American Medical Society for Sports Medicine has identified playing position as a key risk factor for concussion in football and one for which additional research is needed. This study examined variation in head impact outcomes across primary football playing positions in a group of 730 National Collegiate Athletic Association Division I Football Championship Series athletes, using a self-report questionnaire. Although there were no significant differences between position groups in the number of diagnosed concussions during the 2012 football season, there were significant differences between groups in undiagnosed concussions (p=0.008) and “dings” (p<0.001); offensive linemen reported significantly higher numbers than most other positions. Significant differences were found between position groups in the frequencies of several postimpact symptoms, including dizziness (p<0.001), headache (p<0.001), and seeing stars (p<0.001) during the 2012 football season, with offensive linemen reporting significantly more symptoms compared to most other groups. There were also positional differences in frequency of returning to play while symptomatic (p<0.001) and frequency of participating in full-contact practice (p<0.001). Offensive linemen reported having returned to play while experiencing symptoms more frequently and participating in more full-contact practices than other groups. These findings suggest that offensive linemen, a position group that experiences frequent, but low-magnitude, head impacts, develop more postimpact symptoms than other playing positions, but do not report these symptoms as a concussion. PMID:25155288

  2. Mass mortality and extraterrestrial impacts

    NASA Technical Reports Server (NTRS)

    Jansa, L. F.; Gradstein, F. M.; Pierre-Aubry, M.

    1988-01-01

    The discovery of iridium enrichment at the Cretaceous/Tertiary boundary resulted in formulation of hypothesis of a cometary or asteroid impact as the cause of the biological extinctions at this boundary. Subsequent discoveries of geochemical anomalies at major stratigraphic boundaries like the Precambrian/Cambrian, Permian/Triassic, Middle/Late Jurassic, resulted in the application of similar extraterrestrial impact theories to explain biological changes at these boundaries. Until recently the major physical evidence, as is the location of the impact crater site, to test the impact induced biological extinction was lacking. The diameter of such a crater would be in the range of 60 to 100 km. The recent discovery of the first impact crater in the ocean provide the first opportunity to test the above theory. The crater, named Montagnais and located on the outer shelf off Nova Scotia, Canada, has a minimum diameter of 42 km, with some evidence to a diameter of more than 60 km. At the Montagnais impact site, micropaleontological analysis of the uppermost 80 m of the fall-back breccia represented by a mixture of pre-impact sediments and basement rocks which fills the crater and of the basal 50 m of post-impact marine sediments which overly the impact deposits, revealed presence of diversified foraminiferal and nannoplankton assemblages. The sediments which are intercalated within the uppermost part of the fall-back breccia, had to be deposited before the meteorite impact. The post-impact deposits were laid down almost immediately after the impact as also supported by the micropaleontological data. In conclusion, micropaleontological studies of sediments from the first submarine impact crater site identified in the ocean did not reveal any mass extinction or significant biological changes at the impact site or in the proximal deep ocean basin.

  3. Frequency of head-impact-related outcomes by position in NCAA division I collegiate football players.

    PubMed

    Baugh, Christine M; Kiernan, Patrick T; Kroshus, Emily; Daneshvar, Daniel H; Montenigro, Philip H; McKee, Ann C; Stern, Robert A

    2015-03-01

    Concussions and subconcussive impacts sustained in American football have been associated with short- and long-term neurological impairment, but differences in head impact outcomes across playing positions are not well understood. The American Medical Society for Sports Medicine has identified playing position as a key risk factor for concussion in football and one for which additional research is needed. This study examined variation in head impact outcomes across primary football playing positions in a group of 730 National Collegiate Athletic Association Division I Football Championship Series athletes, using a self-report questionnaire. Although there were no significant differences between position groups in the number of diagnosed concussions during the 2012 football season, there were significant differences between groups in undiagnosed concussions (p=0.008) and "dings" (p<0.001); offensive linemen reported significantly higher numbers than most other positions. Significant differences were found between position groups in the frequencies of several postimpact symptoms, including dizziness (p<0.001), headache (p<0.001), and seeing stars (p<0.001) during the 2012 football season, with offensive linemen reporting significantly more symptoms compared to most other groups. There were also positional differences in frequency of returning to play while symptomatic (p<0.001) and frequency of participating in full-contact practice (p<0.001). Offensive linemen reported having returned to play while experiencing symptoms more frequently and participating in more full-contact practices than other groups. These findings suggest that offensive linemen, a position group that experiences frequent, but low-magnitude, head impacts, develop more postimpact symptoms than other playing positions, but do not report these symptoms as a concussion.

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pan, Kuo-Chuan; Ricker, Paul M.; Taam, Ronald E., E-mail: kpan2@illinois.edu, E-mail: pmricker@illinois.edu, E-mail: r-taam@northwestern.edu

    The progenitor systems of Type Ia supernovae (SNe Ia) are still under debate. Based on recent hydrodynamics simulations, non-degenerate companions in the single-degenerate scenario (SDS) should survive the supernova (SN) impact. One way to distinguish between the SDS and the double-degenerate scenario is to search for the post-impact remnant stars (PIRSs) in SN Ia remnants. Using a technique that combines multi-dimensional hydrodynamics simulations with one-dimensional stellar evolution simulations, we have examined the post-impact evolution of helium-rich binary companions in the SDS. It is found that these helium-rich PIRSs (He PIRSs) dramatically expand and evolve to a luminous phase (L {approx}more » 10{sup 4} L{sub Sun }) about 10 yr after an SN explosion. Subsequently, they contract and evolve to become hot blue-subdwarf-like (sdO-like) stars by releasing gravitational energy, persisting as sdO-like stars for several million years before evolving to the helium red-giant phase. We therefore predict that a luminous OB-like star should be detectable within {approx}30 yr after the SN explosion. Thereafter, it will shrink and become an sdO-like star in the central regions of SN Ia remnants within star-forming regions for SN Ia progenitors evolved via the helium-star channel in the SDS. These He PIRSs are predicted to be rapidly rotating (v{sub rot} {approx}> 50 km s{sup -1}) and to have high spatial velocities (v{sub linear} {approx}> 500 km s{sup -1}). Furthermore, if SN remnants have diffused away and are not recognizable at a later stage, He PIRSs could be an additional source of single sdO stars and/or hypervelocity stars.« less

  5. Treatment with the non-ionic surfactant poloxamer P188 reduces DNA fragmentation in cells from bovine chondral explants exposed to injurious unconfined compression.

    PubMed

    Baars, D C; Rundell, S A; Haut, R C

    2006-06-01

    Excessive mechanical loading to a joint has been linked with the development of post-traumatic osteoarthritis (OA). Among the suspected links between impact trauma to a joint and associated degeneration of articular cartilage is an acute reduction in chondrocyte viability. Recently, the non-ionic surfactant poloxamer 188 (P188) has been shown to reduce by approximately 50% the percentage of non-viable chondrocytes 24 h post-injury in chondral explants exposed to 25 MPa of unconfined compression. There is a question whether these acutely 'saved' chondrocytes will continue to degrade over time, as P188 is only thought to act by acute repair of damaged cell membranes. In order to investigate the degradation of traumatized chondrocytes in the longer term, the current study utilized TUNEL staining to document the percentage of cells suffering DNA fragmentation with and without an immediate 24 h period of exposure of the explants to P188 surfactant. In the current study, as in the previous study by this laboratory, chondral explants were excised from bovine metacarpophalangeal joints and subjected to 25 MPa of unconfined compression. TUNEL staining was performed at 1 h, 4 days, and 7 days post-impact. The current study found that P188 was effective in reducing the percentage of cells with DNA fragmentation in impacted explants by approximately 45% at 4 and 7 days post-impact. These data suggest that early P188 intervention was effective in preventing DNA fragmentation of injured chondrocytes. The current hypothesis is that this process was mitigated by the acute repair of damaged plasma membranes by the non-ionic surfactant P188, and that most repaired cells did not continue to degrade as measured by the fragmentation of their DNA.

  6. The magnetic effects of brecciation and shock in meteorites. I - The LL-chondrites

    NASA Technical Reports Server (NTRS)

    Brecher, A.; Stein, J.; Fuhrman, M.

    1977-01-01

    The magnetic behavior of eight LL chondrites is analyzed in detail, and some implications for their modes of formation and evolutionary history are examined. Petrographic features of the specimens are described, and their initial magnetic characteristics are discussed. The demagnetization behavior of the initial magnetization is investigated along with the saturation remanence behavior and paleomagnetic-field intensities. The results indicate that a magnetic field of 0.01 to 0.1 Oe may have been present during postimpact cooling and that severe shock metamorphism may have given rise to the observed magnetic moments and behavior, even in the absence of ambient magnetic fields.

  7. Hydrocode predictions of collisional outcomes: Effects of target size

    NASA Technical Reports Server (NTRS)

    Ryan, Eileen V.; Asphaug, Erik; Melosh, H. J.

    1991-01-01

    Traditionally, laboratory impact experiments, designed to simulate asteroid collisions, attempted to establish a predictive capability for collisional outcomes given a particular set of initial conditions. Unfortunately, laboratory experiments are restricted to using targets considerably smaller than the modelled objects. It is therefore necessary to develop some methodology for extrapolating the extensive experimental results to the size regime of interest. Results are reported obtained through the use of two dimensional hydrocode based on 2-D SALE and modified to include strength effects and the fragmentation equations. The hydrocode was tested by comparing its predictions for post-impact fragment size distributions to those observed in laboratory impact experiments.

  8. Lorre cluster: an outcome of recent asteroid collision

    NASA Astrophysics Data System (ADS)

    Novakovic, B.; Dell'Oro, A.; Cellino, A.; Knezevic, Z.

    2012-09-01

    Here we show an example of a young asteroid cluster located in a dynamically stable region, which was produced by partial disruption of a primitive body about 30 km in size. According to our estimation it is only 1.9±0.3 Myr old, thus its post-impact evolution is very limited. The parent body had a large orbital inclination, and was subject to collisions with typical impact speeds higher by a factor of 2 than in the most common situations encountered in the main belt. For the first time we have at disposal the observable outcome of a very recent event to study high-speed collisions involving primitive asteroids.

  9. Diviner Lunar Radiometer observations of the LCROSS impact.

    PubMed

    Hayne, Paul O; Greenhagen, Benjamin T; Foote, Marc C; Siegler, Matthew A; Vasavada, Ashwin R; Paige, David A

    2010-10-22

    The Lunar Reconnaissance Orbiter (LRO) Diviner instrument detected a thermal emission signature 90 seconds after the Lunar Crater Observation and Sensing Satellite (LCROSS) Centaur impact and on two subsequent orbits. The impact heated a region of 30 to 200 square meters to at least 950 kelvin, providing a sustained heat source for the sublimation of up to ~300 kilograms of water ice during the 4 minutes of LCROSS post-impact observations. Diviner visible observations constrain the mass of the sunlit ejecta column to be ~10(-6) to 10(-5) kilograms per square meter, which is consistent with LCROSS estimates used to derive the relative abundance of the ice within the regolith.

  10. Blasim: A computational tool to assess ice impact damage on engine blades

    NASA Astrophysics Data System (ADS)

    Reddy, E. S.; Abumeri, G. H.; Chamis, C. C.

    1993-04-01

    A portable computer called BLASIM was developed at NASA LeRC to assess ice impact damage on aircraft engine blades. In addition to ice impact analyses, the code also contains static, dynamic, resonance margin, and supersonic flutter analysis capabilities. Solid, hollow, superhybrid, and composite blades are supported. An optional preprocessor (input generator) was also developed to interactively generate input for BLASIM. The blade geometry can be defined using a series of airfoils at discrete input stations or by a finite element grid. The code employs a coarse, fixed finite element mesh containing triangular plate finite elements to minimize program execution time. Ice piece is modeled using an equivalent spherical objective that has a high velocity opposite that of the aircraft and parallel to the engine axis. For local impact damage assessment, the impact load is considered as a distributed force acting over a region around the impact point. The average radial strain of the finite elements along the leading edge is used as a measure of the local damage. To estimate damage at the blade root, the impact is treated as an impulse and a combined stress failure criteria is employed. Parametric studies of local and root ice impact damage, and post-impact dynamics are discussed for solid and composite blades.

  11. Multi-Scale Impact and Compression-After-Impact Modeling of Reinforced Benzoxazine/Epoxy Composites using Micromechanics Approach

    NASA Astrophysics Data System (ADS)

    Montero, Marc Villa; Barjasteh, Ehsan; Baid, Harsh K.; Godines, Cody; Abdi, Frank; Nikbin, Kamran

    A multi-scale micromechanics approach along with finite element (FE) model predictive tool is developed to analyze low-energy-impact damage footprint and compression-after-impact (CAI) of composite laminates which is also tested and verified with experimental data. Effective fiber and matrix properties were reverse-engineered from lamina properties using an optimization algorithm and used to assess damage at the micro-level during impact and post-impact FE simulations. Progressive failure dynamic analysis (PFDA) was performed for a two step-process simulation. Damage mechanisms at the micro-level were continuously evaluated during the analyses. Contribution of each failure mode was tracked during the simulations and damage and delamination footprint size and shape were predicted to understand when, where and why failure occurred during both impact and CAI events. The composite laminate was manufactured by the vacuum infusion of the aero-grade toughened Benzoxazine system into the fabric preform. Delamination footprint was measured using C-scan data from the impacted panels and compared with the predicated values obtained from proposed multi-scale micromechanics coupled with FE analysis. Furthermore, the residual strength was predicted from the load-displacement curve and compared with the experimental values as well.

  12. Contemporary Impact Analysis Methodology for Planetary Sample Return Missions

    NASA Technical Reports Server (NTRS)

    Perino, Scott V.; Bayandor, Javid; Samareh, Jamshid A.; Armand, Sasan C.

    2015-01-01

    Development of an Earth entry vehicle and the methodology created to evaluate the vehicle's impact landing response when returning to Earth is reported. NASA's future Mars Sample Return Mission requires a robust vehicle to return Martian samples back to Earth for analysis. The Earth entry vehicle is a proposed solution to this Mars mission requirement. During Earth reentry, the vehicle slows within the atmosphere and then impacts the ground at its terminal velocity. To protect the Martian samples, a spherical energy absorber called an impact sphere is under development. The impact sphere is composed of hybrid composite and crushable foam elements that endure large plastic deformations during impact and cause a highly nonlinear vehicle response. The developed analysis methodology captures a range of complex structural interactions and much of the failure physics that occurs during impact. Numerical models were created and benchmarked against experimental tests conducted at NASA Langley Research Center. The postimpact structural damage assessment showed close correlation between simulation predictions and experimental results. Acceleration, velocity, displacement, damage modes, and failure mechanisms were all effectively captured. These investigations demonstrate that the Earth entry vehicle has great potential in facilitating future sample return missions.

  13. Impaction durability of porous polyether-ether-ketone (PEEK) and titanium-coated PEEK interbody fusion devices.

    PubMed

    Torstrick, F Brennan; Klosterhoff, Brett S; Westerlund, L Erik; Foley, Kevin T; Gochuico, Joanna; Lee, Christopher S D; Gall, Ken; Safranski, David L

    2018-05-01

    Various surface modifications, often incorporating roughened or porous surfaces, have recently been introduced to enhance osseointegration of interbody fusion devices. However, these topographical features can be vulnerable to damage during clinical impaction. Despite the potential negative impact of surface damage on clinical outcomes, current testing standards do not replicate clinically relevant impaction loading conditions. The purpose of this study was to compare the impaction durability of conventional smooth polyether-ether-ketone (PEEK) cervical interbody fusion devices with two surface-modified PEEK devices that feature either a porous structure or plasma-sprayed titanium coating. A recently developed biomechanical test method was adapted to simulate clinically relevant impaction loading conditions during cervical interbody fusion procedures. Three cervical interbody fusion devices were used in this study: smooth PEEK, plasma-sprayed titanium-coated PEEK, and porous PEEK (n=6). Following Kienle et al., devices were impacted between two polyurethane blocks mimicking vertebral bodies under a constant 200 N preload. The posterior tip of the device was placed at the entrance between the polyurethane blocks, and a guided 1-lb weight was impacted upon the anterior face with a maximum speed of 2.6 m/s to represent the strike force of a surgical mallet. Impacts were repeated until the device was fully impacted. Porous PEEK durability was assessed using micro-computed tomography (µCT) pre- and postimpaction. Titanium-coating coverage pre- and postimpaction was assessed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy. Changes to the surface roughness of smooth and titanium-coated devices were also evaluated. Porous PEEK and smooth PEEK devices showed minimal macroscopic signs of surface damage, whereas the titanium-coated devices exhibited substantial visible coating loss. Quantification of the porous PEEK deformation demonstrated that the porous structure maintained a high porosity (>65%) following impaction that would be available for bone ingrowth, and exhibited minimal changes to pore size and depth. SEM and energy dispersive X-ray spectroscopy analysis of titanium-coated devices demonstrated substantial titanium coating loss after impaction that was corroborated with a decrease in surface roughness. Smooth PEEK showed minimal signs of damage using SEM, but demonstrated a decrease in surface roughness. Although recent surface modifications to interbody fusion devices are beneficial for osseointegration, they may be susceptible to damage and wear during impaction. The current study found porous PEEK devices to show minimal damage during simulated cervical impaction, whereas titanium-coated PEEK devices lost substantial titanium coverage. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  14. Postimpact deformation associated with the late Eocene Chesapeake Bay impact structure in southeastern Virginia

    USGS Publications Warehouse

    Johnson, G.H.; Kruse, S.E.; Vaughn, A.W.; Lucey, J.K.; Hobbs, C. H.; Powars, D.S.

    1998-01-01

    Upper Cenozoic strata covering the Chesapeake Bay impact structure in southeastern Virginia record intermittent differential movement around its buried rim. Miocene strata in a graben detected by seismic surveys on the York River exhibit variable thickness and are deformed above the creater rim. Fan-like interformational and intraformational angular unconformities within Pliocene-Pleistocene strata, which strike parallel to the crater rim and dip 2-3?? away from the crater center, indicate that deformation and deposition were synchronous. Concentric, large-scale crossbedded, bioclastics and bodies of Pliocene age within ~20km of the buried crater rim formed on offshore shoals, presumably as subsiding listric slump blocks rotated near the crater rim.

  15. Evolution of crystalline target rocks and impactites in the chesapeake bay impact structure, ICDP-USGS eyreville B core

    USGS Publications Warehouse

    Horton, J. Wright; Kunk, Michael J.; Belkin, Harvey E.; Aleinikoff, John N.; Jackson, John C.; Chou, I.-Ming

    2009-01-01

    The 1766-m-deep Eyreville B core from the late Eocene Chesapeake Bay impact structure includes, in ascending order, a lower basement-derived section of schist and pegmatitic granite with impact breccia dikes, polymict impact breccias, and cataclas tic gneiss blocks overlain by suevites and clast-rich impact melt rocks, sand with an amphibolite block and lithic boulders, and a 275-m-thick granite slab overlain by crater-fill sediments and postimpact strata. Graphite-rich cataclasite marks a detachment fault atop the lower basement-derived section. Overlying impactites consist mainly of basement-derived clasts and impact melt particles, and coastal-plain sediment clasts are underrepresented. Shocked quartz is common, and coesite and reidite are confirmed by Raman spectra. Silicate glasses have textures indicating immiscible melts at quench, and they are partly altered to smectite. Chrome spinel, baddeleyite, and corundum in silicate glass indicate high-temperature crystallization under silica undersaturation. Clast-rich impact melt rocks contain α-cristobalite and monoclinic tridymite. The impactites record an upward transition from slumped ground surge to melt-rich fallback from the ejecta plume. Basement-derived rocks include amphibolite-facies schists, greenschist(?)-facies quartz-feldspar gneiss blocks and subgreenschist-facies shale and siltstone clasts in polymict impact breccias, the amphibolite block, and the granite slab. The granite slab, underlying sand, and amphibolite block represent rock avalanches from inward collapse of unshocked bedrock around the transient crater rim. Gneissic and massive granites in the slab yield U-Pb sensitive high-resolution ion microprobe (SHRIMP) zircon dates of 615 ± 7 Ma and 254 ± 3 Ma, respectively. Postimpact heating was <~350 °C in the lower basement-derived section based on undisturbed 40Ar/39Ar plateau ages of muscovite and <~150 °C in sand above the suevite based on 40Ar/39Ar age spectra of detrital microcline.

  16. Reducing the risk of public health emergencies for the world’s largest mass gathering

    PubMed Central

    Sun, Xiaodong; Keim, Mark; He, Yongchao; Mahany, Mollie; Yuan, Zheng'an

    2013-01-01

    Mass Gatherings and Public Health   Mass gatherings are highly visible events with the potential for serious health and political consequences if not managed carefully and effectively.1-4 Mass gatherings have been reported to have significant impact upon public health systems throughout the world.5-10 International mass gathering events, such as those associated with the Olympic Games, often carry high political significance and have a historical risk for terrorist attacks.2 Mass gatherings ranging from the subnational level to international the level have also been associated with outbreaks and subsequent spread of communicable diseases. These events have included outbreaks of foodborne shigellosis occurring at an outdoor music festival in the United States.5,6 The annual Hajj pilgrimage in Saudi Arabia has been plagued by public health threats such as fires, stampedes and an outbreak of meningitis.7,9 Influenza outbreaks were also reported during the 2008 World Youth Day mass gathering in Australia.10 Local, provincial and national public health and medical agencies are frequently involved before, during and after a major event. Therefore, disaster risk reduction is a key element for the effective management of mass gatherings. Disaster Risk Reduction Throughout the world, the overall approach to emergencies and disasters has recently shifted from post-impact activities (i.e., ad hoc relief and reconstruction) to a more systematic and comprehensive process of risk management.11 Disaster risk management includes pre-impact disaster risk reduction (i.e., prevention, preparedness and mitigation) as well as post-impact response and recovery).12 While planners may not always have the ability to prevent health hazards from occurring at mass gathering events, the health sector can play an important role in preventing the public health impact of such hazards. This manuscript describes a comprehensive approach for disaster risk reduction as implemented by those entities responsible for health security associated with the 2010 Shanghai World Exposition (Shanghai Expo). PMID:28228984

  17. Testing the Role of Impacts in Warming Early Mars: Comparisons Between 1-D and GCM Results

    NASA Astrophysics Data System (ADS)

    Steakley, K.; Kahre, M. A.; Murphy, J. R.; Haberle, R. M.; Kling, A.

    2017-12-01

    Comet and asteroid impacts have been explored as a potential mechanism for producing warmer and wetter conditions for early Mars and possibly contributing to valley network formation. However, criticisms have been made regarding the timing of large impacts compared to valley network activity and the ability of such impacts to induce long lasting climate changes and the appropriate amount of precipitation. We test the impact heating hypothesis for the late Noachian Mars atmosphere by revisiting the scenarios described in Segura et al. (2008, JGR Planets 113, E11007) with a 3D global climate model (GCM). Segura et al. (2008) showed with a 1-D model that impacts ranging 30-100 km in diameter could in certain cases induce months to years of above-freezing temperatures and tens of cm to meters of rainfall in atmospheres with 150-mbar, 1-bar, or 2-bar surface pressures. We impose the same initial conditions into the Ames Research Center Mars GCM with updated water cycle physics that includes bulk cloud formation, sedimentation, precipitation (liquid or snow), a Manabe moist convection scheme, and the radiative effects of both liquid and ice clouds. Initial conditions in the GCM match those described in Segura et al. (2008) as closely as possible and include a hot post-impact debris layer, a warm atmosphere, and water vapor profiles consistent with the water abundances mobilized by the impact. Scenarios with 30-, 50- and 100- km impactors in 150-mbar, 1-bar, and 2-bar surface pressure cases are explored both with and without radiatively active water clouds. Our goals are to determine how global rainfall totals and global surface temperatures from the GCM compare with the simpler 1-D Segura et al. (2008) model, to examine what rainfall patterns emerge in the GCM and how they compare to the observed valley network distribution, and to more carefully assess the role of cloud microphysics and radiative effects on the duration and intensity of post-impact climates.

  18. Hf isotope evidence for effective impact melt homogenisation at the Sudbury impact crater, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Kenny, Gavin G.; Petrus, Joseph A.; Whitehouse, Martin J.; Daly, J. Stephen; Kamber, Balz S.

    2017-10-01

    We report on the first zircon hafnium-oxygen isotope and trace element study of a transect through one of the largest terrestrial impact melt sheets. The differentiated melt sheet at the 1.85 Ga, originally ca. 200 km in diameter Sudbury impact crater, Ontario, Canada, yields a tight range of uniform zircon Hf isotope compositions (εHf(1850) of ca. -9 to -12). This is consistent with its well-established crustal origin and indicates differentiation from a single melt that was initially efficiently homogenised. We propose that the heterogeneity in other isotopic systems, such as Pb, in early-emplaced impact melt at Sudbury is associated with volatility-related depletion during the impact cratering process. This depletion leaves the isotopic systems of more volatile elements more susceptible to contamination during post-impact assimilation of country rock, whereas the systems of more refractory elements preserve initial homogeneities. Zircon oxygen isotope compositions in the melt sheet are also restricted in range relative to those in the impacted target rocks. However, they display a marked offset approximately one-third up the melt sheet stratigraphy that is interpreted to be a result of post-impact assimilation of 18O-enirched rocks into the base of the cooling impact melt. Given that impact cratering was a more dominant process in the early history of the inner Solar System than it is today, and the possibility that impact melt sheets were sources of ex situ Hadean zircon grains, these findings may have significance for the interpretation of the early zircon Hf record. We speculate that apparent εHf-time arrays observed in the oldest terrestrial and lunar zircon datasets may be related to impact melting homogenising previously more diverse crust. We also show that spatially restricted partial melting of rocks buried beneath the superheated impact melt at Sudbury provided a zircon crystallising environment distinct to the impact melt sheet itself.

  19. Strontium and neodymium isotope systematics of target rocks and impactites from the El'gygytgyn impact structure: Linking impactites and target rocks

    NASA Astrophysics Data System (ADS)

    Wegner, Wencke; Koeberl, Christian

    2016-12-01

    The 3.6 Ma El'gygytgyn structure, located in northeastern Russia on the Chukotka Peninsula, is an 18 km diameter complex impact structure. The bedrock is formed by mostly high-silica volcanic rocks of the 87 Ma old Okhotsk-Chukotka Volcanic Belt (OCVB). Volcanic target rocks and impact glasses collected on the surface, as well as drill core samples of bedrock and impact breccias have been investigated by thermal ionization mass spectrometry (TIMS) to obtain new insights into the relationships between these lithologies in terms of Nd and Sr isotope systematics. Major and trace element data for impact glasses are added to compare with the composition of target rocks and drill core samples. Sr isotope data are useful tracers of alteration processes and Nd isotopes reveal characteristics of the magmatic sources of the target rocks, impact breccias, and impact glasses. There are three types of target rocks mapped on the surface: mafic volcanics, dacitic tuff and lava of the Koekvun' Formation, and dacitic to rhyolitic ignimbrite of the Pykarvaam Formation. The latter represents the main contributor to the impact rocks. The drill core is divided into a suevite and a bedrock section by the Sr isotope data, for which different postimpact alteration regimes have been detected. Impact glasses from the present-day surface did not suffer postimpact hydrothermal alteration and their data indicate a coherent alteration trend in terms of Sr isotopes with the target rocks from the surface. Surprisingly, the target rocks do not show isotopic coherence with the Central Chukotka segment of the OCVB or with the Berlozhya magmatic assemblage (BMA), a late Jurassic felsic volcanic suite that crops out in the eastern part of the central Chukotka segment of the OCVB. However, concordance for these rocks exists with the Okhotsk segment of the OCVB. This finding argues for variable source magmas having contributed to the build-up of the OCVB.

  20. High speed imaging for assessment of impact damage in natural fibre biocomposites

    NASA Astrophysics Data System (ADS)

    Ramakrishnan, Karthik Ram; Corn, Stephane; Le Moigne, Nicolas; Ienny, Patrick; Leger, Romain; Slangen, Pierre R.

    2017-06-01

    The use of Digital Image Correlation has been generally limited to the estimation of mechanical properties and fracture behaviour at low to moderate strain rates. High speed cameras dedicated to ballistic testing are often used to measure the initial and residual velocities of the projectile but rarely for damage assessment. The evaluation of impact damage is frequently achieved post-impact using visual inspection, ultrasonic C-scan or other NDI methods. Ultra-high speed cameras and developments in image processing have made possible the measurement of surface deformations and stresses in real time during dynamic cracking. In this paper, a method is presented to correlate the force- displacement data from the sensors to the slow motion tracking of the transient failure cracks using real-time high speed imaging. Natural fibre reinforced composites made of flax fibres and polypropylene matrix was chosen for the study. The creation of macro-cracks during the impact results in the loss of stiffness and a corresponding drop in the force history. However, optical instrumentation shows that the initiation of damage is not always evident and so the assessment of damage requires the use of a local approach. Digital Image Correlation is used to study the strain history of the composite and to identify the initiation and progression of damage. The effect of fly-speckled texture on strain measurement by image correlation is also studied. The developed method can be used for the evaluation of impact damage for different composite materials.

  1. Partitioning of a Falling Droplet's Energy After Surface Impact

    NASA Astrophysics Data System (ADS)

    Kern, Vanessa; Steen, Paul

    2017-11-01

    Understanding energy partitioning post-impact is a first step to understanding immersive flow-forming processes. Here we investigate the partitioning of kinetic energy into surface energies for capillary water droplets falling onto homogeneous prepared hydrophilic, hydrophobic and super-hydrophobic surfaces. We analyze high-speed images of the impact event. Pre-impact Weber numbers range from 0-15. After impact and initial spreading, the droplet's contact line pins. After pinning, there is a slow decay to the rest state. During this underdamped decay, the droplet's remaining kinetic energy partitions into a linear combination of mode shape energies. These mode shapes and their frequencies correspond to those of pinned sessile droplets from theory. The influence of impact energy on modes excited will be discussed.

  2. Lunar Bouguer gravity anomalies - Imbrian age craters

    NASA Technical Reports Server (NTRS)

    Dvorak, J.; Phillips, R. J.

    1978-01-01

    The Bouguer gravity of mass anomalies associated with four Imbrian age craters, analyzed in the present paper, are found to differ considerably from the values of the mass anomalies associated with some young lunar craters. Of the Imbrian age craters, only Piccolomini exhibits a negative gravity anomaly (i.e., a low density region) which is characteristic of the young craters studied. The Bouguer gravity anomalies are zero for each of the remaining Imbrian age craters. Since, Piccolomini is younger, or at least less modified, than the other Imbrian age craters, it is suggested that the processes responsible for the post-impact modification of the Imbrian age craters may also be responsible for removing the negative mass anomalies initially associated with these features.

  3. New insight into lunar impact melt mobility from the LRO camera

    USGS Publications Warehouse

    Bray, Veronica J.; Tornabene, Livio L.; Keszthelyi, Laszlo P.; McEwen, Alfred S.; Hawke, B. Ray; Giguere, Thomas A.; Kattenhorn, Simon A.; Garry, William B.; Rizk, Bashar; Caudill, C.M.; Gaddis, Lisa R.; van der Bogert, Carolyn H.

    2010-01-01

    The Lunar Reconnaissance Orbiter Camera (LROC) is systematically imaging impact melt deposits in and around lunar craters at meter and sub-meter scales. These images reveal that lunar impact melts, although morphologically similar to terrestrial lava flows of similar size, exhibit distinctive features (e.g., erosional channels). Although generated in a single rapid event, the post-impact mobility and morphology of lunar impact melts is surprisingly complex. We present evidence for multi-stage influx of impact melt into flow lobes and crater floor ponds. Our volume and cooling time estimates for the post-emplacement melt movements noted in LROC images suggest that new flows can emerge from melt ponds an extended time period after the impact event.

  4. Fatigue resistance of unnotched and post impact(+/- 30 deg/0 deg) 3-D braided composites

    NASA Technical Reports Server (NTRS)

    Portanova, Marc A.

    1994-01-01

    The fatigue resistance of a multiaxial braided (3-D) graphite/expoxy composite in both unnotched and post impacted conditions has been evaluated. The material tested is a (+/- 30/0 deg) multiaxial braid constructed from AS4/12K tow graphite fibers and British Petroleum E905L epoxy resin. These materials were braided as dry preforms and the epoxy was added using a resin transfer molding process (RTM). The unnotched and post-impact specimens were tested in compression-compression fatigue at 10 Hz with a stress ratio of R=10. The unnotched tension-tension fatigue specimens were tested at S Hz with a stress ration of R=0.1. Damage initiation and growth was documented through the application of radiography and ultrasonic through transmission (C-scans). Visible inspection of surface and edge damage was also noted to describe the initiation and progression of damage in these materials. The mechanisms leading to damage initiation were established and failure modes were determined. Stiffness and strength degradation were measured as a function of applied cycles. These 3-D braided composite results were compared to strain levels currently used to design primary structure in commercial aircraft composite components made from prepreg tape and autoclave cured.

  5. A Nine Kilometer Impact Crater and Its Central Peak

    NASA Image and Video Library

    2017-02-08

    found across the Martian surface. Each impact crater on Mars possesses a unique origin and composition, which makes the HiRISE team very interested in sampling as many of them as possible! Like the impact of a droplet into fluid, once an impact has occurred on the surface of Mars, an ejecta curtain forms immediately after, contributing to the raised rim visible at the top of the crater's walls. After the formation of the initial crater, if it is large enough, then a central peak appears as the surface rebounds. These central peaks can expose rocks that were previously deeply buried beneath the Martian surface. The blue and red colors in this enhanced-contrast image reflect the effects of post-impact sedimentation and weathering over time. http://photojournal.jpl.nasa.gov/catalog/PIA08395

  6. Could giant basin-forming impacts have killed Martian dynamo?

    PubMed Central

    Kuang, W; Jiang, W; Roberts, J; Frey, H V

    2014-01-01

    The observed strong remanent crustal magnetization at the surface of Mars suggests an active dynamo in the past and ceased to exist around early to middle Noachian era, estimated by examining remagnetization strengths in extant and buried impact basins. We investigate whether the Martian dynamo could have been killed by these large basin-forming impacts, via numerical simulation of subcritical dynamos with impact-induced thermal heterogeneity across the core-mantle boundary. We find that subcritical dynamos are prone to the impacts centered on locations within 30° of the equator but can easily survive those at higher latitudes. Our results further suggest that magnetic timing places a strong constraint on postimpact polar reorientation, e.g., a minimum 16° polar reorientation is needed if Utopia is the dynamo killer. PMID:26074641

  7. Could Giant Basin-Forming Impacts Have Killed Martian Dynamo?

    NASA Technical Reports Server (NTRS)

    Kuang, W.; Jiang, W.; Roberts, J.; Frey, H. V.

    2014-01-01

    The observed strong remanent crustal magnetization at the surface of Mars suggests an active dynamo in the past and ceased to exist around early to middle Noachian era, estimated by examining remagnetization strengths in extant and buried impact basins. We investigate whether the Martian dynamo could have been killed by these large basin-forming impacts, via numerical simulation of subcritical dynamos with impact-induced thermal heterogeneity across the core-mantle boundary. We find that subcritical dynamos are prone to the impacts centered on locations within 30 deg of the equator but can easily survive those at higher latitudes. Our results further suggest that magnetic timing places a strong constraint on postimpact polar reorientation, e.g., a minimum 16 deg polar reorientation is needed if Utopia is the dynamo killer.

  8. Could giant basin-forming impacts have killed Martian dynamo?

    PubMed

    Kuang, W; Jiang, W; Roberts, J; Frey, H V

    2014-11-28

    The observed strong remanent crustal magnetization at the surface of Mars suggests an active dynamo in the past and ceased to exist around early to middle Noachian era, estimated by examining remagnetization strengths in extant and buried impact basins. We investigate whether the Martian dynamo could have been killed by these large basin-forming impacts, via numerical simulation of subcritical dynamos with impact-induced thermal heterogeneity across the core-mantle boundary. We find that subcritical dynamos are prone to the impacts centered on locations within 30° of the equator but can easily survive those at higher latitudes. Our results further suggest that magnetic timing places a strong constraint on postimpact polar reorientation, e.g., a minimum 16° polar reorientation is needed if Utopia is the dynamo killer.

  9. Impact experiments onto heterogeneous targets and their interpretation in relation with formation of the asteroid families

    NASA Astrophysics Data System (ADS)

    Leliwa-Kopystynski, J.; Arakawa, M.

    2014-07-01

    Results of laboratory impact experiments, when extrapolated to the planetary scale of events, are aimed for better understanding of cratering and/or disruption of asteroids, satellites, and cometary nuclei. There is absolutely no reason to assume that these bodies are uniform rocky or icy monoliths. So, we studied reactions of the heterogeneous targets on the impacts. A series of impact experiments onto solid decimeter-sized cylinders made of porous gypsum mixed with approximately one-centimeter-sized pebbles have been performed. The mean density of the material of the targets was 1867 kg m^{-3}, the mean mass ratio (pebbles / gypsum) = 0.856 / 0.144, and the mean volume ratio (pebbles / gypsum / pores) = 0.585 / 0.116 / 0.299. The target densities and their heterogeneous structures could be representative of those of the asteroids Ida, Eros, and many others, because asteroid sub-surface volumes could be composed of consolidated boulders formed by self-compaction and/or by impact compaction. Impact velocities in the experiments ranged from 2.0 km/s to 6.7 km/s (collision velocity in the asteroid main belt is approximately 5 km/s). By means of weighting and counting the post-impact fragments, their distribution function was found. Let Q [J/kg] be the specific energy of impact per unit of the target mass. Of particular interest is the value of impact strength, that is, the specific energy of disruption Q^*, corresponding to the ratio (mass of the largest fragment) / (mass of the target) = m_l/M = 0.5, which is, by convention, the value separating the cratering events from the catastrophic disruption impacts. Mass or size distribution of the post-impact fragments is expressed by the power law N ∝ m^{-p} ∝ r^{-3p}, p=p(Q/Q^{*}) A parameter that can be measured in the laboratory is the exponent p. For the case of a swarm of asteroids forming an asteroid family, the observationally estimated value is not the exponent p but rather the exponent q = 3p, since the sizes r of the family members are better known than their masses m (because then the asteroids' densities should be known). We have found that, for the gypsum/pebbles targets, there is Q^* ≈ 270 J/kg and the exponent q varies linearly with rather high slope: q = (0.705 ± 0.093)(Q/Q^{*}) + (2.7 ± 1.2) for 1 < Q/Q^* < 40, approximately. For comparison, this result differs considerably from that for porous water ice targets with porosity equal to 0.37 and specific energy of disruption Q^* ≈ 39 J/kg (based on the data presented in Fig. 9 of Arakawa et al., 2002). In that case, q has only a slight slope: q = (0.092 ± 0.020)(Q/Q^*) + (1.30 ± 0.22) for 1 < Q/Q^* < 20, approximately. The presence of pebbles strongly influences the impact strength of the target as well as the size distribution of the post-impact fragments. Formulae (2) and (3) indicate that the increase of specific impact energy delivered to the target leads to more efficient comminuting. Comparison with the experimental size distribution within families of asteroids is in progress.

  10. Raining a magma ocean: Thermodynamics of rocky planets after a giant impact

    NASA Astrophysics Data System (ADS)

    Stewart, S. T.; Lock, S. J.; Caracas, R.

    2017-12-01

    Rocky planets in exoplanetary systems have equilibrium temperatures up to a few 1000 K. The thermal evolution after a giant impact is sensitive to the equilibrium temperature. Post-impact rocky bodies are thermally stratified, with cooler, lower-entropy silicate overlain by vaporized, higher-entropy silicate. The radii of impact-vaporized rocky planets are much larger than the radii of equivalent condensed bodies. Furthermore, after some high-energy, high-angular momentum collisions, the post-impact body exceeds the corotation limit for a rocky planet and forms a synestia. Initially, volatiles and silicates are miscible at the high temperatures of the outer layer. If the equilibrium temperature with the star is lower than the silicate condensation temperature ( 2000 K), silicate droplets form at the photosphere and fall while volatile components remain in the vapor. Radiation and turbulent convection cool the vapor outer layer to the silicate vapor curve. A distinct magma ocean forms as the thermal profile crosses the silicate vapor curve and the critical curves for the volatiles. Near the temperatures and pressures of the critical curves, volatiles and silicates are partially soluble in each other. As the system continues cooling, the volatile vapor and silicate liquid separate toward the end member compositions, which are determined by the equilibrium temperature and the total vapor pressure of volatiles. If the equilibrium temperature with the star is near or above the condensation temperature for silicates, there would be limited condensation at the photosphere. Initially, the cooler lower mantle would slowly, diffusively equilibrate with the hotter upper mantle. In some cases, the thermal profile may cross the silicate vapor curve in the middle of the silicate layer, producing a silicate rain layer within the body. With continued evolution toward an adiabatic thermal profile, the body would separate into a silicate liquid layer underlying a silicate-volatile vapor layer. As the hottest rocky planets become tidally locked to their star, cooling progresses asymmetrically. The timing and degree of differentiation of rocky planets into silicate mantles and volatile atmospheres depends on the thermal evolution of vaporized rocky planets and may vary widely with equilibrium temperature.

  11. The central uplift of Elorza Crater: Insights into its geology and possible relationships to the Valles Marineris and Tharsis regions

    NASA Astrophysics Data System (ADS)

    Hopkins, R. T.; Tornabene, L. L.; Osinski, G. R.

    2017-03-01

    The majority of hydrated silicate occurrences on Mars are associated with impact craters (Ehlmann et al., 2011; Carter et al., 2013). Three formation mechanisms have been suggested to account for this correlation: (1) aqueous alteration occurred pre-impact, and was subsequently exposed via the impact (pre-impact; Bibring et al., 2006; Ehlmann et al., 2011), (2) heat generated from the impact facilitated the formation of a hydrothermal system, leading to alteration products (syn-impact; e.g. Marzo et al., 2010; Osinski et al., 2013), and/or (3) altered materials were deposited after crater formation, or formed within the crater well after the impact had taken place (post-impact). In this study, we analyze the central uplift of Elorza Crater, a ∼40 km diameter impact crater located ∼300 km north of Valles Marineris. To determine whether hydrated minerals found within the uplift were generated pre-, syn-, or post-impact, we used a data synthesis approach, utilizing High Resolution Imaging Science Experiment (HiRISE), Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), Context Camera (CTX), and Thermal Emission Imaging System (THEMIS) imagery. Opaline silica is observed in two locations on the southwestern side of the uplift and is interpreted to have been pre-existing or formed via hydrothermal alteration due to stratigraphic relationships with the overlying impact melt unit. Both Fe/Mg smectite and low-calcium pyroxene (LCP) are found throughout the uplift. Bedrock exposures on the northern wall of Coprates Chasma containing Fe/Mg smectite and LCP suggest an uplifted origin for these units. In all cases, although a pre-existing origin is probable, it is difficult to rule out the possibility of an impact-generated hydrothermal origin. Using the observed stratigraphy exposed in Coprates Chasma and bedrock exposures analyzed in nearby craters, we were able to constrain the pre-impact stratigraphy around Elorza. The near-subsurface consists of Hesperian-aged, discontinuous lava/ash deposits that may be interposed with opaline silica-bearing deposits, overlying Noachian basement consisting of smectite-bearing bedrock and LCP- bearing light-toned fractured bedrock.

  12. Aqueous origins of bright salt deposits on Ceres

    NASA Astrophysics Data System (ADS)

    Zolotov, Mikhail Yu.

    2017-11-01

    Bright materials have been reported in association with impact craters on Ceres. The abundant Na2CO3 and some ammonium salts, NH4HCO3 and/or NH4Cl, were detected in bright deposits within Occator crater with Dawn near infrared spectroscopy. The composition and appearance of the salts suggest their aqueous mobilization and emplacement after formation of the crater. Here we consider origins of the bright deposits through calculation of speciation in the H-C-N-O-Na-Cl water-salt type system constrained by the mass balance of observed salts. Calculations of chemical equilibria show that initial solutions had the pH of ∼10. The temperature and salinity of solutions could have not exceeded ∼273 K and ∼100 g per kg H2O, respectively. Freezing models reveal an early precipitation of Na2CO3·10H2O followed by minor NaHCO3. Ammonium salts precipitate near eutectic from brines enriched in NH4+, Cl- and Na+. A late-stage precipitation of NaCl·2H2O is modeled for solution compositions with added NaCl. Calculated eutectics are above 247 K. The apparently unabundant ammonium and chloride salts in Occator's deposits imply a rapid emplacement without a compositional evolution of solution. Salty ice grains could have deposited from post-impact ballistic plumes formed through low-pressure boiling of subsurface solutions. Hydrated and ammonium salts are unstable at maximum temperatures of Ceres' surface and could decompose through space weathering. Occator's ice-free salt deposits formed through a post-depositional sublimation of ice followed by dehydration of Na2CO3·10H2O and NaHCO3 to Na2CO3. In other regions, excavated and exposed bright materials could be salts initially deposited from plumes and accumulated at depth via post-impact boiling. The lack of detection of sulfates and an elevated carbonate/chloride ratio in Ceres' materials suggest an involvement of compounds abundant in the outer solar system.

  13. An Event-Triggered Machine Learning Approach for Accelerometer-Based Fall Detection.

    PubMed

    Putra, I Putu Edy Suardiyana; Brusey, James; Gaura, Elena; Vesilo, Rein

    2017-12-22

    The fixed-size non-overlapping sliding window (FNSW) and fixed-size overlapping sliding window (FOSW) approaches are the most commonly used data-segmentation techniques in machine learning-based fall detection using accelerometer sensors. However, these techniques do not segment by fall stages (pre-impact, impact, and post-impact) and thus useful information is lost, which may reduce the detection rate of the classifier. Aligning the segment with the fall stage is difficult, as the segment size varies. We propose an event-triggered machine learning (EvenT-ML) approach that aligns each fall stage so that the characteristic features of the fall stages are more easily recognized. To evaluate our approach, two publicly accessible datasets were used. Classification and regression tree (CART), k -nearest neighbor ( k -NN), logistic regression (LR), and the support vector machine (SVM) were used to train the classifiers. EvenT-ML gives classifier F-scores of 98% for a chest-worn sensor and 92% for a waist-worn sensor, and significantly reduces the computational cost compared with the FNSW- and FOSW-based approaches, with reductions of up to 8-fold and 78-fold, respectively. EvenT-ML achieves a significantly better F-score than existing fall detection approaches. These results indicate that aligning feature segments with fall stages significantly increases the detection rate and reduces the computational cost.

  14. Lunar and Planetary Science XXXVI, Part 15

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Contents include the following: Impact Metamorphism of Subsurface Organic Matter on Mars: A Potential Source for Methane and Surface Alteration. Preliminary Study of Polygonal Impact Craters in Argyre Region, Mars. Geochemistry of the Dark Veinlets in the Granitoids from the Souderfjarden Impact Structure, Finland: Preliminary Results. An Experimental Method to Estimate the Chemical Reaction Rate in Vapor Clouds: An Application to the K/T Impact. Study of the Apollo 16 Landing Site: Re-Visit as a Standard Site for the SELENE Multiband Imager. First X-Ray Observation of Lunar Farside from Hayabusa X-Ray Spectrometer. Lunar X-Ray Fluorescence Spectrometry from SELENE Lunar Polar Orbiter. Origin and Thermal History of Lithic Materials in the Begaa LL3 Chondrite. Evidence of Normal Faulting and Dike Intrusion at Valles Marineris from Pit Crater Topography. Evidence of Tharsis-Radial Dike Intrusion in Southeast Alba Patera from MOLA-based Topography of Pit Crater Chains. Are They Really Intact? Evaluation of Captured Micrometeoroid Analogs by Aerogel at the Flyby Speed of Stardust. Numerical Simulations of Impactor Penetration into Ice-Over-Water Targets. A Probable Fluid Lava Flow in the Hebes Mensa (Mars) Studied by HRSC Images. New Drill-Core Data from the Lockne Crater, Sweden: The Marine Excavation and Ejection Processes, and Post-Impact Environment. Cross-Sectional Profile of Baltis Vallis Channel on Venus: Reconstruction from Magellan SAR Brightness Data.

  15. A critical review of environmental impact statements in Sri Lanka with particular reference to ecological impact assessment.

    PubMed

    Samarakoon, Miriya; Rowan, John S

    2008-03-01

    This article critically reviews environmental assessment (EA) practices in Sri Lanka, with a particular focus on ecology. An overview is provided of the domestic and international influences which have shaped the administrative process which is currently a two-tiered scheme. An Initial Environmental Examination (IEE) provides a preliminary screening tool, prior to the requirement for a full Environmental Impact Assessment (EIA). A comprehensive survey of Sri Lankan national archives showed that 463 EAs were completed in the period 1981-2005, with the bulk of these in the more populated Western and North Western Provinces. Two-thirds were IEE surveys, while the remaining third advanced to full EIA. A representative sample of 130 EAs (both IEEs and full EIAs) spanning a broad range of project types, scales, and environmental settings was selected to evaluate the quality of the ecological investigations within the published environmental impact statements (EISs). These were assigned into five classes of "explanatory power", on the basis of their scientific content in relation to survey, analysis, and reporting of ecological interests. Within most EISs, the ecological impact assessment (EcIA) was restricted to the lowest two categories of ecological assessment, i.e., tokenistic presentation of reconnaissance-level species lists without further analysis of the development implications for individual organisms or communities. None of the assessments reviewed provided statistically rigorous analysis, which would be required if ecological impact studies are to include quantitative and testable predictions of impact, which could then be followed up by appropriate post-impact monitoring programs. Attention to key local issues such as biodiversity or ecosystem services, which also have strong social dimensions in the developing world, was also notably underrepresented. It was thus concluded that despite the existence of a sound legislative framework in Sri Lanka, the analysis contained within EISs generally fails to convey meaningful information to the relevant stakeholders and decision makers involved in protecting ecological interests and promoting sustainable development. The introduction of strategic environmental assessment (SEA) is considered an important tool to strengthen the institutional capacity of Sri Lankan government to implement current regulations and, in particular, to combat the cumulative effects of incremental development.

  16. High-velocity projectile impact induced 9R phase in ultrafine-grained aluminium.

    PubMed

    Xue, Sichuang; Fan, Zhe; Lawal, Olawale B; Thevamaran, Ramathasan; Li, Qiang; Liu, Yue; Yu, K Y; Wang, Jian; Thomas, Edwin L; Wang, Haiyan; Zhang, Xinghang

    2017-11-21

    Aluminium typically deforms via full dislocations due to its high stacking fault energy. Twinning in aluminium, although difficult, may occur at low temperature and high strain rate. However, the 9R phase rarely occurs in aluminium simply because of its giant stacking fault energy. Here, by using a laser-induced projectile impact testing technique, we discover a deformation-induced 9R phase with tens of nm in width in ultrafine-grained aluminium with an average grain size of 140 nm, as confirmed by extensive post-impact microscopy analyses. The stability of the 9R phase is related to the existence of sessile Frank loops. Molecular dynamics simulations reveal the formation mechanisms of the 9R phase in aluminium. This study sheds lights on a deformation mechanism in metals with high stacking fault energies.

  17. Post-Impact Fatigue Damage Monitoring Using Fiber Bragg Grating Sensors

    PubMed Central

    Shin, Chow-Shing; Liaw, Shien-Kuei; Yang, Shi-Wei

    2014-01-01

    It has been shown that impact damage to composite materials can be revealed by embedded Fiber Bragg Gratings (FBG) as a broadening and splitting of the latter's characteristic narrow peak reflected spectrum. The current work further subjected the impact damaged composite to cyclic loading and found that the FBG spectrum gradually submerged into a rise of background intensity as internal damages progressed. By skipping the impact, directing the impact to positions away from the FBG and examining the extracted fibers, we concluded that the above change is not a result of deterioration/damage of the sensor. It is caused solely by the damages initiated in the composite by the impact and aggravated by fatigue loading. Evolution of the grating spectrum may therefore be used to monitor qualitatively the development of the incurred damages. PMID:24594609

  18. Impact Lithologies and Post-Impact Hydrothermal Alteration Exposed by the Chicxulub Scientific Drilling Project, Yaxcopoil, Mexico

    NASA Technical Reports Server (NTRS)

    Kring, David A.; Zurcher, Lukas; Horz, Friedrich

    2003-01-01

    The Chicxulub Scientific Drilling Project recovered a continuous core from the Yaxcopoil-1 (YAX-1) borehole, which is approx.60-65 km from the center of the Chicxulub structure, approx.15 km beyond the limit of the estimated approx.50 km radius transient crater (excavation cavity), but within the rim of the estimated approx.90 km radius final crater. Approximately approx.100 m of melt-bearing impactites were recoverd from a depth of 794 to 895 m, above approx.600 m of underlying megablocks of Cretaceous target sediments, before bottoming at 1511 m. Compared to lithologies at impact craters like the Ries, the YAX-1 impactite sequence is incredibly rich in impact melts of unusual textural variety and complexity. The impactite sequence has also been altered by hydrothermal activity that may have largely been produced by the impact event.

  19. Hypervelocity Impact Testing of IM7/977-3 with Micro-Sized Particles

    NASA Technical Reports Server (NTRS)

    Smith, J. G.; Jegley, D. C.; Siochi, E. J.; Wells, B. K.

    2010-01-01

    Ground-based hypervelocity imapct testing was conducted on IM7/977-3 quasi-isotropic flat panels at normal incidence using micron-sized particles (i.e. less than or equal to 100 microns) of soda lime glass and olivine. Testing was performed at room temperature (RT) and 175 C with results from the 175 C test compared to those obtained at RT. Between 10 and 30 particles with velocities ranging from 5 to 13 km/s impacted each panel surface for each test temperature. Panels were ultrasonically scanned prior to and after impact testing to assess internal damage. Post-impact analysis included microscopic examination of the surface, determination of particle speed and location, and photomicroscopy for microcrack assessment. Internal damage was observed by ultrasonic inspection on panels impacted at 175 C, whereas damage for the RT impacted panels was confined to surface divets/craters as determined by microscopic analysis.

  20. Post-Impact and Open Hole Tensile Of Kenaf Hybrid Composites

    NASA Astrophysics Data System (ADS)

    Yunus, S.; Salleh, Z.; Masdek, N. R. N. M.; Taib, Y. M.; Azhar, I. I. S.; Hyie, K. M.

    2018-03-01

    Nowadays, kenaf hybrid glass composites has been used for a vast field of study throughout the globe. There are several compositions and orientation of kenaf hybrid glass composites that has been studied. With regards to the study that has been done, this study will be focussing on a 90FG/0/90/90/0/90FG orientation of kenaf hybrid glass composites. Polyester resin is used as a matrix to these hybrid composites. Impacted and open hole specimens were then analyzed through tensile test. All specimens were fabricated by using the cold press hand lay-up technique. The results revealed that the hybrid composites were hardly affected by the impact up to 6J. After 6J the impacted specimens experienced a significant damage for both strength and modulus. The same goes to open hole specimens where the same trend of tensile properties were observed as impacted specimens.

  1. Recent collisional jet from a primitive asteroid

    NASA Astrophysics Data System (ADS)

    Novaković, Bojan; Dell'Oro, Aldo; Cellino, Alberto; Knežević, Zoran

    2012-09-01

    In this paper we show an example of a young asteroid cluster located in a dynamically stable region, which was produced by partial disruption of a primitive body about 30 km in size. We estimate its age to be only 1.9 ± 0.3 Myr; thus, its post-impact evolution should have been very limited. The large difference in size between the largest object and the other cluster members means that this was a cratering event. The parent body had a large orbital inclination and was subject to collisions with typical impact speeds higher by a factor of 2 than in the most common situations encountered in the main belt. For the first time, we have at our disposal the observable outcome of a very recent event to study high-speed collisions involving primitive asteroids, providing very useful constraints to numerical simulations of these events and to laboratory experiments.

  2. Ballistic impacts on an anatomically correct synthetic skull with a surrogate skin/soft tissue layer.

    PubMed

    Mahoney, Peter; Carr, Debra; Arm, Richard; Gibb, Iain; Hunt, Nicholas; Delaney, Russ J

    2018-03-01

    The aim of this work was to further develop a synthetic model of ballistic head injury by the addition of skin and soft tissue layers to an anatomically correct polyurethane skull filled with gelatine 10% by mass. Six head models were impacted with 7.62 x 39 mm full metal jacket mild steel core (FMJ MSC) bullets with a mean velocity of 652 m/s. The impact events were filmed with high-speed cameras. The models were imaged pre- and post-impact using computed tomography. The models were assessed post impact by two experienced Home Office pathologists and the images assessed by an experienced military radiologist. The findings were scored against real injuries. The entry wounds, exit wounds and fracture patterns were scored positively, but the synthetic skin and soft tissue layer was felt to be too extendable. Further work is ongoing to address this.

  3. Browsing Space Weather Data and Models with the Integrated Space Weather Analysis (iSWA) System

    NASA Technical Reports Server (NTRS)

    Maddox, Marlo M.; Mullinix, Richard E.; Berrios, David H.; Hesse, Michael; Rastaetter, Lutz; Pulkkinen, Antti; Hourcle, Joseph A.; Thompson, Barbara J.

    2011-01-01

    The Integrated Space Weather Analysis (iSWA) System is a comprehensive web-based platform for space weather information that combines data from solar, heliospheric and geospace observatories with forecasts based on the most advanced space weather models. The iSWA system collects, generates, and presents a wide array of space weather resources in an intuitive, user-configurable, and adaptable format - thus enabling users to respond to current and future space weather impacts as well as enabling post-impact analysis. iSWA currently provides over 200 data and modeling products, and features a variety of tools that allow the user to browse, combine, and examine data and models from various sources. This presentation will consist of a summary of the iSWA products and an overview of the customizable user interfaces, and will feature several tutorial demonstrations highlighting the interactive tools and advanced capabilities.

  4. Anomalous K-Pg-aged seafloor attributed to impact-induced mid-ocean ridge magmatism.

    PubMed

    Byrnes, Joseph S; Karlstrom, Leif

    2018-02-01

    Eruptive phenomena at all scales, from hydrothermal geysers to flood basalts, can potentially be initiated or modulated by external mechanical perturbations. We present evidence for the triggering of magmatism on a global scale by the Chicxulub meteorite impact at the Cretaceous-Paleogene (K-Pg) boundary, recorded by transiently increased crustal production at mid-ocean ridges. Concentrated positive free-air gravity and coincident seafloor topographic anomalies, associated with seafloor created at fast-spreading rates, suggest volumes of excess magmatism in the range of ~10 5 to 10 6 km 3 . Widespread mobilization of existing mantle melt by post-impact seismic radiation can explain the volume and distribution of the anomalous crust. This massive but short-lived pulse of marine magmatism should be considered alongside the Chicxulub impact and Deccan Traps as a contributor to geochemical anomalies and environmental changes at K-Pg time.

  5. Anomalous K-Pg–aged seafloor attributed to impact-induced mid-ocean ridge magmatism

    PubMed Central

    Byrnes, Joseph S.; Karlstrom, Leif

    2018-01-01

    Eruptive phenomena at all scales, from hydrothermal geysers to flood basalts, can potentially be initiated or modulated by external mechanical perturbations. We present evidence for the triggering of magmatism on a global scale by the Chicxulub meteorite impact at the Cretaceous-Paleogene (K-Pg) boundary, recorded by transiently increased crustal production at mid-ocean ridges. Concentrated positive free-air gravity and coincident seafloor topographic anomalies, associated with seafloor created at fast-spreading rates, suggest volumes of excess magmatism in the range of ~105 to 106 km3. Widespread mobilization of existing mantle melt by post-impact seismic radiation can explain the volume and distribution of the anomalous crust. This massive but short-lived pulse of marine magmatism should be considered alongside the Chicxulub impact and Deccan Traps as a contributor to geochemical anomalies and environmental changes at K-Pg time. PMID:29441360

  6. A model of the primordial lunar atmosphere

    NASA Astrophysics Data System (ADS)

    Saxena, Prabal; Elkins-Tanton, Lindy; Petro, Noah; Mandell, Avi

    2017-09-01

    We create the first quantitative model for the early lunar atmosphere, coupled with a magma ocean crystallization model. Immediately after formation, the moon's surface was subject to a radiative environment that included contributions from the early Sun, a post-impact Earth that radiated like a mid-type M dwarf star, and a cooling global magma ocean. This radiative environment resulted in a largely Earth-side atmosphere on the Moon, ranging from ∼104 to ∼102 pascals, composed of heavy volatiles (Na and SiO). This atmosphere persisted through lid formation and was additionally characterized by supersonic winds that transported significant quantities of moderate volatiles and likely generated magma ocean waves. The existence of this atmosphere may have influenced the distribution of some moderate volatiles and created temperature asymmetries which influenced ocean flow and cooling. Such asymmetries may characterize young, tidally locked rocky bodies with global magma oceans and subject to intense irradiation.

  7. A Model of the Primordial Lunar Atmosphere

    NASA Technical Reports Server (NTRS)

    Saxena, Prabal; Elkins-Tanton, Lindy; Petro, Noah; Mandell, Avi

    2017-01-01

    We create the first quantitative model for the early lunar atmosphere, coupled with a magma ocean crystallization model. Immediately after formation, the moon's surface was subject to a radiative environment that included contributions from the early Sun, a post-impact Earth that radiated like a mid-type M dwarf star, and a cooling global magma ocean. This radiative environment resulted in a largely Earth-side atmosphere on the Moon, ranging from approximately 10(exp 4) to approximately 10(exp 2) pascals, composed of heavy volatiles (Na and SiO). This atmosphere persisted through lid formation and was additionally characterized by supersonic winds that transported significant quantities of moderate volatiles and likely generated magma ocean waves. The existence of this atmosphere may have influenced the distribution of some moderate volatiles and created temperature asymmetries which influenced ocean flow and cooling. Such asymmetries may characterize young, tidally locked rocky bodies with global magma oceans and subject to intense irradiation.

  8. Benthic foraminiferal responses to operational drill cutting discharge in the SW Barents Sea - a case study.

    NASA Astrophysics Data System (ADS)

    Aagaard-Sørensen, Steffen; Junttila, Juho; Dijkstra, Noortje

    2016-04-01

    Petroleum related exploration activities started in the Barents Sea 1980, reaching 97 exploration wells drilled per January 2013. The biggest operational discharge from drilling operations in the Barents Sea is the release of drill cuttings (crushed seabed and/or bedrock) and water based drilling muds including the commonly used weighing material barite (BaSO4). Barium (Ba), a constituent of barite, does not degrade and can be used to evaluate dispersion and accumulation of drill waste. The environmental impact associated with exploration drilling within the Goliat Field, SW Barents Sea in 2006 was evaluated via a multiproxy investigation of local sediments. The sediments were retrieved in November 2014 at ~350 meters water depth and coring sites were selected at distances of 5, 30, 60, 125 and 250 meters from the drill hole in the eastward downstream direction. The dispersion pattern of drill waste was estimated via measurements of sediment parameters including grain size distribution and water content in addition to heavy metal and total organic carbon contents. The environmental impact was evaluated via micro faunal analysis based on benthic foraminiferal (marine shell bearing protists) fauna composition and concentration changes. Observing the sediment parameters, most notably Ba levels, reveals that dispersion of drill waste was limited to <125 meters from the drill site with drill waste thicknesses decreasing downstream. The abruptness and quantity of drill waste sedimentation initially smothered the foraminiferal fauna at ≤ 30 meters from the drill site, while at a distance of 60 meters, the fauna seemingly survived and bioturbation persisted. Analysis of the live (Nov 2014) foraminiferal fauna reveals a natural species composition at all distances from the drill site within the top sediments (0-5 cm core depth). Furthermore, the fossil foraminiferal fauna composition found within post-impacted top sediment sections, particularly in the cores situated at 30 and 60 meters from the drill site, suggests that reestablishment of the foraminiferal fauna likely commenced shortly after cessation of drilling activity.

  9. Where is the Geophysical Evidence for the Giant Impact Origin of the Pluto System?

    NASA Astrophysics Data System (ADS)

    McKinnon, W. B.; Singer, K. N.; Nimmo, F.; Spencer, J. R.; Young, L. A.; Weaver, H. A., Jr.; Stern, S. A.

    2016-12-01

    Prior to the New Horizons flyby of the Pluto system, it was anticipated that both Pluto and Charon might show geological or geophysical evidence of the giant impact thought responsible for the formation of Charon and the smaller satellites. Although dynamical and compositional evidence still supports the giant impact model (McKinnon et al., submitted to Icarus), the question remains as to whether the geology of Pluto or Charon records evidence of this cataclysm. The collision speed and energy were most likely not large enough to melt all the ices in the precursor bodies, so surviving geological evidence is not out of the question. Specifically, Pluto post-impact should have been rapidly rotating (with a period as short as 5-6 hr) and highly distorted; Charon under most circumstances would have rapidly despun but have been a highly distorted triaxial body. The tidal evolution end state for both is close to spherical, but fossil figures were anticipated, which in addition to providing direct evidence for post-impact tidal evolution, would provide important clues to thermal and structural evolution. For Pluto, McKinnon and Singer (DPS 2014, abs. 419.07) predicted a flattening >1% (radii differences >10 km) for a strengthless icy lithosphere and an unrelaxed rock core. For a fully relaxed core, they predicted a >2-3 km fossil bulge supported by icy lithospheric strength (corresponding to a minimum past lithosphere thickness of 50 km). New Horizons image analyses have limited any oblateness for Pluto to 0.6% (Nimmo et al., Icarus, in press), which corresponds to <7 km flattening. So Pluto may yet possess a geophysically meaningful oblateness, only one not yet directly detectable (moreover, in order to be consistent with the observations, Pluto's rock core either completed its formation post-spindown, or was too weak to support much non-hydrostatic topography). Such an equator-to-pole surface elevation difference, even a subtle one, could express itself through control of Pluto's zonal albedo pattern (i.e., dark, reddish Cthulhu Regio, Krun and other Macula are all equatorial [names are informal]). Even for a completely relaxed shape, the tectonic effects on Pluto's surface should be manifest. There is a rich variety of tectonic expression, but no obvious match to classic predicted tectonic despinning patterns.

  10. New Laboratory-Based Satellite Impact Experiments for Breakup Fragment Characterization

    NASA Technical Reports Server (NTRS)

    Liou, J.-C.; Fitz-Coy, N.; Dikova, R.; Wilson, M.; Huynh, T.; Sorge, M.; Sheaffer, P.; Opiela, J.; Cowardin, H.; Krisko, P.; hide

    2014-01-01

    A consortium consisting of the NASA Orbital Debris Program Office, U.S. Air Force's Space and Missile Systems Center, the Aerospace Corporation, and University of Florida is planning a series of hypervelocity impact experiments on mockup targets at the U.S. Air Force's Arnold Engineering Development Complex (AEDC) in early 2014. The target for the first experiment resembles a rocket upper stage whereas the target for the second experiment represents a typical 60-cm/50-kg class payload that incorporates modern spacecraft materials and components as well as exterior wrap of multi-layer insulation and three solar panels. The projectile is designed with the maximum mass that AEDC's Range G two-stage light gas gun can accelerate to an impact speed of 7 km/sec. The impact energy is expected to be close to 15 MJ to ensure catastrophic destruction of the target after the impact. Low density foam panels are installed inside the target chamber to slow down and soft-catch the fragments for post-impact processing. Diagnostic instruments, such as x-ray and high speed optical cameras, will also be used to record the breakup process. The main goal of this "DebriSat" project is to characterize the physical properties, including size, mass, shape, and density distributions, of orbital debris that would be generated by a hypervelocity collision involving an upper stage or a modern satellite in the low Earth orbit environment. In addition, representative fragments will be selected for laboratory optical and radar measurements to allow for better interpretation of data obtained by telescope and radar observations. This paper will provide a preliminary report of the impact results and the plans to process, measure, and analyze the fragments.

  11. Aerosol Sampling System for Collection of Capstone Depleted Uranium Particles in a High-Energy Environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Holmes, Thomas D.; Guilmette, Raymond A.; Cheng, Yung-Sung

    2009-03-01

    The Capstone Depleted Uranium Aerosol Study was undertaken to obtain aerosol samples resulting from a kinetic-energy cartridge with a large-caliber depleted uranium (DU) penetrator striking an Abrams or Bradley test vehicle. The sampling strategy was designed to (1) optimize the performance of the samplers and maintain their integrity in the extreme environment created during perforation of an armored vehicle by a DU penetrator, (2) collect aerosols as a function of time post-impact, and (3) obtain size-classified samples for analysis of chemical composition, particle morphology, and solubility in lung fluid. This paper describes the experimental setup and sampling methodologies used tomore » achieve these objectives. Custom-designed arrays of sampling heads were secured to the inside of the target in locations approximating the breathing zones of the vehicle commander, loader, gunner, and driver. Each array was designed to support nine filter cassettes and nine cascade impactors mounted with quick-disconnect fittings. Shielding and sampler placement strategies were used to minimize sampler loss caused by the penetrator impact and the resulting fragments of eroded penetrator and perforated armor. A cyclone train was used to collect larger quantities of DU aerosol for chemical composition and solubility. A moving filter sample was used to obtain semicontinuous samples for depleted uranium concentration determination. Control for the air samplers was provided by five remotely located valve control and pressure monitoring units located inside and around the test vehicle. These units were connected to a computer interface chassis and controlled using a customized LabVIEW engineering computer control program. The aerosol sampling arrays and control systems for the Capstone study provided the needed aerosol samples for physicochemical analysis, and the resultant data were used for risk assessment of exposure to DU aerosol.« less

  12. Paleoenvironmental recovery from the Chesapeake Bay bolide impact: The benthic foraminiferal record

    USGS Publications Warehouse

    Poag, C.W.

    2009-01-01

    The late Eocene Chesapeake Bay bolide impact transformed its offshore target site from an outer neritic, midshelf seafl oor into a bathyal crater basin. To obtain a depositional record from one of the deepest parts of this basin, the U.S. Geological Survey (USGS) and the International Continental Scientifi c Drilling Program (ICDP) drilled a 1.76-km-deep core hole near Eyreville, Virginia. The Eyreville core and eight previously cored boreholes contain a rarely obtainable record of marine deposition and microfossil assemblages that characterize the transition from synimpact to postimpact paleoenvironments inside and near a submarine impact crater. I used depositional style and benthic foraminiferal assemblages to recognize a four-step transitional succession, with emphasis on the Eyreville core. Step 1 is represented by small-scale, silt-rich turbidites, devoid of indigenous microfossils, which lie directly above the crater-fi lling Exmore breccia. Step 2 is represented by very thin, parallel, silt and clay laminae, which accumulated on a relatively tranquil and stagnant seafl oor. This stagnation created a dead zone, which excluded seafl oor biota, and it lasted ~3-5 ka. Step 3 is an interval of marine clay deposition, accompanied by a burst of microfaunal activity, as a species-rich pioneer community of benthic foraminifera repopulated the impact site. The presence of a diagnostic suite of agglutinated foraminifera during step 3 indicates that paleoenvironmental stress related to the impact lasted from ~9 ka to 400 ka at different locations inside the crater. During step 4, the agglutinated assemblage disappeared, and an equilibrium foraminiferal community developed that contained nearly 100% calcareous species. In contrast to intracrater localities, core sites outside and near the crater rim show neither evidence of the agglutinated assemblage, nor other indications of long-term biotic disruption from the bolide impact. 

  13. X-ray microtomography study of the spallation response in Ta-W

    NASA Astrophysics Data System (ADS)

    McDonald, Samuel; Cotton, Matthew; Millett, Jeremy; Bourne, Neil; Withers, Philip

    2013-06-01

    The response of metallic materials to high strain-rate (impact) loading is of interest to a number of communities. Traditionally, the largest driver has been the military, in its need to understand armour and resistance to ballistic attack. More recently, industries such as aerospace (foreign object damage, bird strike, etc.), automotive (crash-worthiness) and satellite protection (orbital debris) have all appreciated the necessity of such information. It is therefore important to understand the dynamic tensile or spallation response, and in particular to be able to observe in three-dimensions, and in a non-invasive manner, the physical damage present in the spalled region post-impact. The current study presents plate impact experiments investigating the spallation damage response of recovered targets of the tantalum alloy Ta-2.5%W. Using X-ray microtomography the damage resulting from differing impact conditions (impact velocity/stress, pulse duration) is compared and characterised in 3-D. Combined with free surface velocity measurements, the tensile failure mechanisms during dynamic loading have been identified.

  14. Chicxulub Impact Melts: Geochemical Signatures of Target Lithology Mixing and Post-Impact Hydrothermal Fluid Processes

    NASA Technical Reports Server (NTRS)

    Kring, David A.; Zurcher, Lukas; Horz, Freidrich; Mertzmann, Stanley A.

    2004-01-01

    Impact melts within complex impact craters are generally homogeneous, unless they differentiated, contain immiscible melt components, or were hydrothermally altered while cooling. The details of these processes, however, and their chemical consequences, are poorly understood. The best opportunity to unravel them may lie with the Chicxulub impact structure, because it is the world s most pristine (albeit buried) large impact crater. The Chicxulub Scientific Drilling Project recovered approx. 100 meters of impactites in a continuous core from the Yaxcopoil-1 (YAX-1) borehole. This dramatically increased the amount of melt available for analyses, which was previously limited to two small samples N17 and N19) recovered from the Yucatan-6 (Y-6) borehole and one sample (N10) recovered from the Chicxulub-1 (C-1) borehole. In this study, we describe the chemical compositions of six melt samples over an approx. 40 m section of the core and compare them to previous melt samples from the Y-6 and C-1 boreholes.

  15. An impact analysis of a flexible bat using an iterative solver.

    PubMed

    Penrose, J M; Hose, D R

    1999-08-01

    Although technology has now infiltrated and prompted evolution in most mass participation sports, the advances in bat technology in such sports as baseball and cricket have been relatively minor. In this study, we used a simple finite element modelling approach to try to shed new light upon the underlying mechanics of the bat-ball impact, with a view to the future optimization of bat design. The analysis of a flexible bat showed that the point of impact that produced the maximum post-impact ball velocity was a function of the bat's vibrational properties and was not necessarily at the centre of percussion. The details of the analysis agreed well with traditional Hertzian impact theory, and broadly with empirical data. An inspection of the relative modal contributions to the deformations during impact also showed that the position of the node of the first flexure mode was important. In conclusion, considerable importance should be attached to the bat's vibrational properties in future design and analysis.

  16. Noachian Impact Ejecta on Murray Ridge and Pre-impact Rocks on Wdowiak Ridge, Endeavour Crater, Mars: Opportunity Observations

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Gellert, R.; Ming, D. W.; Morris, R. V.; Schroeder, C.; Yen, A. S.; Farrand, W. H.; Arvidson, R. E.; Franklin, B. J.; Grant, J. A.; hide

    2015-01-01

    Mars Exploration Rover Opportunity has been exploring Meridiani Planum since January 2004, and has completed 4227% of its primary mission. Opportunity has been investigating the geology of the rim of 22 km diameter Endeavour crater, first on the Cape York segment and now on Cape Tribulation. The outcrops are divided York; (ii) the Shoemaker fm, impact breccias representing ejecta from the crater; into three formations: (i) the lower Matijevic fm, a pre-impact lithology on Cape and (iii) the upper Grasberg fm, a post-impact deposit that drapes the lower portions of the eroded rim segments. On the Cape Tribulation segment Opportunity has been studying the rocks on Murray Ridge, with a brief sojourn to Wdowiak Ridge west of the rim segment. team member Thomas Wdowiak, who died in 2013.) One region of Murray Ridge has distinctive CRISM spectral characteristics indicating the presence of a small concentration of aluminous smectite based on a 2.2 micron Al-OH combination band (hereafter, the Al-OH region).

  17. Oblique collisions of baseballs and softballs with a bat

    NASA Astrophysics Data System (ADS)

    Kensrud, Jeffrey R.; Nathan, Alan M.; Smith, Lloyd V.

    2017-07-01

    Experiments are done by colliding a swinging bat with a stationary baseball or softball. Each collision was recorded with high-speed cameras from which the post-impact speed, launch angle, and spin of the ball could be determined. Initial bat speeds were in the range 63-88 mph, producing launch angles in the range 0°-30° and spins in the range 0-3,500 rpm. The results are analyzed in the context of a ball-bat collision model, and the parameters of that model are determined. For both baseballs and softballs, the data are consistent with a mechanism whereby the ball grips the surface of the bat, stretching the ball in the transverse direction and resulting in a spin that was up to 40% greater than would be obtained by rolling contact of rigid bodies. Using a lumped parameter contact model, baseballs are shown to be less compliant tangentially than softballs. Implications of our results for batted balls in game situations are presented.

  18. Influence of Fault-Controlled Topography on Fluvio-Deltaic Sedimentary Systems in Eberswalde Crater, Mars

    NASA Technical Reports Server (NTRS)

    Rice, Melissa S.; Gupta, Sanjeev; Bell, James F., III; Warner, Nicholas H.

    2011-01-01

    Eberswalde crater was selected as a candidate landing site for the Mars Science Laboratory (MSL) mission based on the presence of a fan-shaped sedimentary deposit interpreted as a delta. We have identified and mapped five other candidate fluvio -deltaic systems in the crater, using images and digital terrain models (DTMs) derived from the Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) and Context Camera (CTX). All of these systems consist of the same three stratigraphic units: (1) an upper layered unit, conformable with (2) a subpolygonally fractured unit, unconformably overlying (3) a pitted unit. We have also mapped a system of NNE-trending scarps interpreted as dip-slip faults that pre-date the fluvial -lacustrine deposits. The post-impact regional faulting may have generated the large-scale topography within the crater, which consists of a Western Basin, an Eastern Basin, and a central high. This topography subsequently provided depositional sinks for sediment entering the crater and controlled the geomorphic pattern of delta development.

  19. Hydrodynamical simulations of the stream-core interaction in the slow merger of massive stars

    NASA Astrophysics Data System (ADS)

    Ivanova, N.; Podsiadlowski, Ph.; Spruit, H.

    2002-08-01

    We present detailed simulations of the interaction of a stream emanating from a mass-losing secondary with the core of a massive supergiant in the slow merger of two stars inside a common envelope. The dynamics of the stream can be divided into a ballistic phase, starting at the L1 point, and a hydrodynamical phase, where the stream interacts strongly with the core. Considering the merger of a 1- and 5-Msolar star with a 20-Msolar evolved supergiant, we present two-dimensional hydrodynamical simulations using the PROMETHEUS code to demonstrate how the penetration depth and post-impact conditions depend on the initial properties of the stream material (e.g. entropy, angular momentum, stream width) and the properties of the core (e.g. density structure and rotation rate). Using these results, we present a fitting formula for the entropy generated in the stream-core interaction and a recipe for the determination of the penetration depth based on a modified Bernoulli integral.

  20. Morphological Indicators of a Mascon Beneath Ceres's Largest Crater, Kerwan

    NASA Astrophysics Data System (ADS)

    Bland, M. T.; Ermakov, A. I.; Raymond, C. A.; Williams, D. A.; Bowling, T. J.; Preusker, F.; Park, R. S.; Marchi, S.; Castillo-Rogez, J. C.; Fu, R. R.; Russell, C. T.

    2018-02-01

    Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long-term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from viscous relaxation in an outer layer that thins substantially beneath the crater floor. We propose that such a structure is consistent with either impact-induced uplift of the high-density mantle beneath the crater or from volatile loss during the impact event. In either case, the subsurface structure inferred from the crater morphology is superisostatic, and the mass excess would result in a positive Bouguer anomaly beneath the crater, consistent with the highest-degree gravity data from Dawn. Ceres joins the Moon, Mars, and Mercury in having basin-associated gravity anomalies, although their origin may differ substantially.

  1. Modeling drop impacts on inclined flowing soap films

    NASA Astrophysics Data System (ADS)

    Basu, Saikat; Yawar, Ali; Concha, Andres; Bandi, Mahesh

    2015-11-01

    Small drops impinging on soap films flowing at an angle primarily exhibit three fundamental regimes of post-impact dynamics: (a) the drop bounces off the film surface, (b) it coalesces with the downstream flow, and (c) it pierces through the film. During impact, the drop deforms along with a simultaneous, almost elastic deformation of the film transverse to the stream direction. Hence, the governing dynamics for this interaction present the rare opportunity to explore the in-tandem effects of elasticity and hydrodynamics alike. In this talk, we outline the analytical framework to study the drop impact dynamics. The model assumes a deformable drop and a deformable three-dimensional soap film and invokes a parametric study to qualify the three mentioned impact types. The physical parameters include the impact angle, drop impact speed, and the diameters of the drop prior to and during impact when it deforms and spreads out. Our model system offers a path towards optimization of interactions between a spray and a flowing liquid.

  2. Morphological indicators of a mascon beneath Ceres' largest crater, Kerwan

    USGS Publications Warehouse

    Bland, Michael T.; Ermakov, Anton; Raymond, Carol A.; Williams, David A.; Bowling, Tim J.; Preusker, F.; Park, Ryan S.; Marchi, Simone; Castillo-Rogez, Julie C.; Fu, R.R.; Russell, Christopher T.

    2018-01-01

    Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long‐term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from viscous relaxation in an outer layer that thins substantially beneath the crater floor. We propose that such a structure is consistent with either impact‐induced uplift of the high‐density mantle beneath the crater or from volatile loss during the impact event. In either case, the subsurface structure inferred from the crater morphology is superisostatic, and the mass excess would result in a positive Bouguer anomaly beneath the crater, consistent with the highest‐degree gravity data from Dawn. Ceres joins the Moon, Mars, and Mercury in having basin‐associated gravity anomalies, although their origin may differ substantially.

  3. High Resolution Vertical Seismic Profile from the Chicxulub IODP/ICDP Expedition 364 Borehole: Wave Speeds and Seismic Reflectivity.

    NASA Astrophysics Data System (ADS)

    Nixon, C.; Kofman, R.; Schmitt, D. R.; Lofi, J.; Gulick, S. P. S.; Christeson, G. L.; Saustrup, S., Sr.; Morgan, J. V.

    2017-12-01

    We acquired a closely-spaced vertical seismic profile (VSP) in the Chicxulub K-Pg Impact Crater drilling program borehole to calibrate the existing surface seismic profiles and provide complementary measurements of in situ seismic wave speeds. Downhole seismic records were obtained at spacings ranging from 1.25 m to 5 m along the borehole from 47.5 m to 1325 mwsf (meters wireline below sea floor) (Fig 1a) using a Sercel SlimwaveTM geophone chain (University of Alberta). The seismic source was a 30/30ci Sercel Mini GI airgun (University of Texas), fired a minimum of 5 times per station. Seismic data processing used a combination of a commercial processing package (Schlumberger's VISTA) and MatlabTM codes. The VSP displays detailed reflectivity (Fig. 1a) with the strongest reflection seen at 600 mwsf (280 ms one-way time), geologically corresponding to the sharp contact between the post-impact sediments and the target peak ring rock, thus confirming the pre-drilling interpretations of the seismic profiles. A two-way time trace extracted from the separated up-going wavefield matches the major reflection both in travel time and character. In the granitic rocks that form the peak ring of the Chicxulub impact crater, we observe P-wave velocities of 4000-4500 m/s which are significantly less than the expected values of granitoids ( 6000 m/s) (Fig. 1b). The VSP measured wave speeds are confirmed against downhole sonic logging and in laboratory velocimetry measurements; these data provide additional evidence that the crustal material displaced by the impact experienced a significant amount of damage. Samples and data provided by IODP. Samples can be requested at http://web.iodp.tamu.edu/sdrm after 19 October 2017. Expedition 364 was jointly funded by ECORD, ICDP, and IODP with contributions and logistical support from the Yucatan State Government and UNAM. The downhole seismic chain and wireline system is funded by grants to DRS from the Canada Foundation for Innovation and the Alberta Enterprise and Advanced Education Grants Program.

  4. Extraordinary rocks from the peak ring of the Chicxulub impact crater: P-wave velocity, density, and porosity measurements from IODP/ICDP Expedition 364

    NASA Astrophysics Data System (ADS)

    Christeson, G. L.; Gulick, S. P. S.; Morgan, J. V.; Gebhardt, C.; Kring, D. A.; Le Ber, E.; Lofi, J.; Nixon, C.; Poelchau, M.; Rae, A. S. P.; Rebolledo-Vieyra, M.; Riller, U.; Schmitt, D. R.; Wittmann, A.; Bralower, T. J.; Chenot, E.; Claeys, P.; Cockell, C. S.; Coolen, M. J. L.; Ferrière, L.; Green, S.; Goto, K.; Jones, H.; Lowery, C. M.; Mellett, C.; Ocampo-Torres, R.; Perez-Cruz, L.; Pickersgill, A. E.; Rasmussen, C.; Sato, H.; Smit, J.; Tikoo, S. M.; Tomioka, N.; Urrutia-Fucugauchi, J.; Whalen, M. T.; Xiao, L.; Yamaguchi, K. E.

    2018-08-01

    Joint International Ocean Discovery Program and International Continental Scientific Drilling Program Expedition 364 drilled into the peak ring of the Chicxulub impact crater. We present P-wave velocity, density, and porosity measurements from Hole M0077A that reveal unusual physical properties of the peak-ring rocks. Across the boundary between post-impact sedimentary rock and suevite (impact melt-bearing breccia) we measure a sharp decrease in velocity and density, and an increase in porosity. Velocity, density, and porosity values for the suevite are 2900-3700 m/s, 2.06-2.37 g/cm3, and 20-35%, respectively. The thin (25 m) impact melt rock unit below the suevite has velocity measurements of 3650-4350 m/s, density measurements of 2.26-2.37 g/cm3, and porosity measurements of 19-22%. We associate the low velocity, low density, and high porosity of suevite and impact melt rock with rapid emplacement, hydrothermal alteration products, and observations of pore space, vugs, and vesicles. The uplifted granitic peak ring materials have values of 4000-4200 m/s, 2.39-2.44 g/cm3, and 8-13% for velocity, density, and porosity, respectively; these values differ significantly from typical unaltered granite which has higher velocity and density, and lower porosity. The majority of Hole M0077A peak-ring velocity, density, and porosity measurements indicate considerable rock damage, and are consistent with numerical model predictions for peak-ring formation where the lithologies present within the peak ring represent some of the most shocked and damaged rocks in an impact basin. We integrate our results with previous seismic datasets to map the suevite near the borehole. We map suevite below the Paleogene sedimentary rock in the annular trough, on the peak ring, and in the central basin, implying that, post impact, suevite covered the entire floor of the impact basin. Suevite thickness is 100-165 m on the top of the peak ring but 200 m in the central basin, suggesting that suevite flowed downslope from the collapsing central uplift during and after peak-ring formation, accumulating preferentially within the central basin.

  5. 3D numerical model of the southern polar giant impact for the formation of the Martian dichotomy

    NASA Astrophysics Data System (ADS)

    Leone, Giovanni; Tackley, Paul J.; Gerya, Taras; May, David A.; Zhu, Guizhi

    2013-04-01

    Lack of volcanism and/or crustal flows in the northern lowlands poses serious problems to the hypothesis of formation of the Borealis basin by giant impact in the Northern Polar region of Mars. We use numerical modeling integrated with a geologic and volcanologic study of the surface of Mars to investigate an alternative process of formation that involves a giant impact on the South Pole, resulting in a hemispherical magma pond and resulting thicker crust. We have performed 3D simulations of Martian evolution from the immediate post-impact stage to the present day for different combinations of impactor sizes and compositions, ranging from 900 km radius and sideritic composition (up to 80% radius iron) to 1750 km radius and mesosiderite-type composition (50% radius iron; nickel neglected at the moment). The main reason for considering siderites is the presence of M-type asteroids like 16 Psyche (and several others) in the asteroid belt, the likely remnants of larger parent bodies in the 1-2 AU range which then migrated to their current position after giant impacts with protoplanets. We assume an impactor speed similar to the escape velocity of the target body, consistent with N-body simulations. Our results show that this is a viable formation hypothesis for the southern highlands. Our preferred scenario is of a lunar sized impactor of 1600 km radius with a 70% iron (by radius) fraction, hitting the south Pole at a speed of 5 km/s (the escape velocity of Mars), melting much of the interior and 1/2 of the planetary surface with the creation of a magma ocean that formed the highlands upon cooling and solidification. Regarding timing, we find that this should have happened after 4 Ma after CAI, because before this the strong heating from short-lived radiogenic elements coupled with the thermal anomaly generated by the giant impact would erase by re-melting any newly formed crust. Using a combination of I3ELVIS (immediate post-impact and core formation) and STAGYY (long-term) thermo-mechanical codes, we are now studying the long-term consequences of such a giant impact: a) thermal and compositional effect on core formation; b) triggering of a transient magnetic field, traces of which have been detected on both the hemispheres; c) start-up of migrating mantle plumes from the southern polar region to the equator following two preferential paths, northwest to Tharsis and northeast to Elysium.

  6. A Comparative Analysis of the Magnetic Field Signals over Impact Structures on the Earth, Mars and the Moon

    NASA Technical Reports Server (NTRS)

    Isac, Anca; Mandea, Mioara; Purucker, Michael; Langlais, Benoit

    2015-01-01

    An improved description of magnetic fields of terrestrial bodies has been obtained from recent space missions, leading to a better characterization of the internal fields including those of crustal origin. One of the striking differences in their crustal magnetic field is the signature of large impact craters. A comparative analysis of the magnetic characteristics of these structures can shed light on the history of their respective planetary-scale magnetic dynamos. This has motivated us to identify impact craters and basins, first by their quasi-circular features from the most recent and detailed topographic maps and then from available global magnetic field maps. We have examined the magnetic field observed above 27 complex craters on the Earth, 34 impact basins on Mars and 37 impact basins on the Moon. For the first time, systematic trends in the amplitude and frequency of the magnetic patterns, inside and outside of these structures are observed for all three bodies. The demagnetization effects due to the impact shock wave and excavation processes have been evaluated applying the Equivalent Source Dipole forward modeling approach. The main characteristics of the selected impact craters are shown. The trends in their magnetic signatures are indicated, which are related to the presence or absence of a planetary-scale dynamo at the time of their formation and to impact processes. The low magnetic field intensity at center can be accepted as the prime characteristic of a hypervelocity impact and strongly associated with the mechanics of impact crater formation. In the presence of an active internal field, the process of demagnetization due to the shock impact is associated with post-impact remagnetization processes, generating a more complex magnetic signature.

  7. Compressive strength after blast of sandwich composite materials

    PubMed Central

    Arora, H.; Kelly, M.; Worley, A.; Del Linz, P.; Fergusson, A.; Hooper, P. A.; Dear, J. P.

    2014-01-01

    Composite sandwich materials have yet to be widely adopted in the construction of naval vessels despite their excellent strength-to-weight ratio and low radar return. One barrier to their wider use is our limited understanding of their performance when subjected to air blast. This paper focuses on this problem and specifically the strength remaining after damage caused during an explosion. Carbon-fibre-reinforced polymer (CFRP) composite skins on a styrene–acrylonitrile (SAN) polymer closed-cell foam core are the primary composite system evaluated. Glass-fibre-reinforced polymer (GFRP) composite skins were also included for comparison in a comparable sandwich configuration. Full-scale blast experiments were conducted, where 1.6×1.3 m sized panels were subjected to blast of a Hopkinson–Cranz scaled distance of 3.02 m kg−1/3, 100 kg TNT equivalent at a stand-off distance of 14 m. This explosive blast represents a surface blast threat, where the shockwave propagates in air towards the naval vessel. Hopkinson was the first to investigate the characteristics of this explosive air-blast pulse (Hopkinson 1948 Proc. R. Soc. Lond. A 89, 411–413 (doi:10.1098/rspa.1914.0008)). Further analysis is provided on the performance of the CFRP sandwich panel relative to the GFRP sandwich panel when subjected to blast loading through use of high-speed speckle strain mapping. After the blast events, the residual compressive load-bearing capacity is investigated experimentally, using appropriate loading conditions that an in-service vessel may have to sustain. Residual strength testing is well established for post-impact ballistic assessment, but there has been less research performed on the residual strength of sandwich composites after blast. PMID:24711494

  8. Bouncing and coalescence of droplets on falling liquid films

    NASA Astrophysics Data System (ADS)

    Che, Zhizhao; Deygas, Amandine; Matar, Omar

    2014-11-01

    When a droplet impacts on a falling liquid film, the outcome depends on the fluid properties of the droplet, its speed, and angle of incidence, as well as on the film flow rate and associated flow regimes. In this study, the oblique impact of droplets on a falling liquid film is investigated experimentally. The falling film is created on an inclined substrate and the Reynolds number is varied. Droplets with different sizes and different speeds are used to study the impact process for different Weber and Ohnesorge numbers. Different phenomena of droplet impact are identified and analysed, such as bouncing, partial coalescence, total coalescence, and splashing. An impact regime map is generated, and the effects of droplet impact speed and size, and the film flow rates are studied. The propagation of waves on the liquid film post-impact is analysed. The results show that the flowing film can significantly affect the impact process of droplets, and the latter can alter the propagation of waves on the falling film. EPSRC Programme Grant, MEMPHIS, EP/K0039761/1.

  9. Post-impact behavior of composite solid rocket motor cases

    NASA Technical Reports Server (NTRS)

    Highsmith, Alton L.

    1992-01-01

    In recent years, composite materials have seen increasing use in advanced structural applications because of the significant weight savings they offer when compared to more traditional engineering materials. The higher cost of composites must be offset by the increased performance that results from reduced structural weight if these new materials are to be used effectively. At present, there is considerable interest in fabricating solid rocket motor cases out of composite materials, and capitalizing on the reduced structural weight to increase rocket performance. However, one of the difficulties that arises when composite materials are used is that composites can develop significant amounts of internal damage during low velocity impacts. Such low velocity impacts may be encountered in routine handling of a structural component like a rocket motor case. The ability to assess the reduction in structural integrity of composite motor cases that experience accidental impacts is essential if composite rocket motor cases are to be certified for manned flight. The study described herein was an initial investigation of damage development and reduction of tensile strength in an idealized composite subjected to low velocity impacts.

  10. Foreign Object Damage in a Gas-Turbine Grade Silicon Nitride by Spherical Projectiles of Various Materials

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Racz, Zsolt; Bhatt, Ramakrishna T.; Brewer, David N.

    2006-01-01

    Assessments of foreign object damage (FOD) of a commercial, gas-turbine grade, in situ toughened silicon nitride ceramic (AS800, Honeywell Ceramics Components) were made using four different projectile materials at ambient temperature. AS800 flexure target specimens rigidly supported were impacted at their centers in a velocity range from 50 to 450 m/s by spherical projectiles with a diameter of 1.59 mm. Four different projectile materials were used including hardened steel, annealed steel, silicon nitride ceramic, and brass. Post-impact strength of each target specimen impacted was determined as a function of impact velocity to appraise the severity of local impact damage. For a given impact velocity, the degree of strength degradation was greatest for ceramic balls, least for brass balls, and intermediate for annealed and hardened steel balls. For steel balls, hardened projectiles yielded more significant impact damage than annealed counterparts. The most important material parameter affecting FOD was identified as hardness of projectiles. Impact load as a function of impact velocity was quasi-statically estimated based on both impact and static indentation associated data.

  11. Comparison of lunar rocks and meteorites: Implications to histories of the moon and parent meteorite bodies

    NASA Technical Reports Server (NTRS)

    Prinz, M.; Fodor, R. V.; Keil, K.

    1974-01-01

    A number of similarities between lunar and meteoritic rocks are reported and suggest that the comparison is essential for a clear understanding of meteorites as probes of the early history of the solar systems: (1) Monomict and polymict breccias occur in lunar rocks, as well as in achondritic and chondritic meteorites, having resulted from complex and repeated impact processes. (2) Chondrules are present in lunar, as well as in a few achondritic and most chondritic meteorites. It is pointed out that because chondrules may form in several different ways and in different environments, a distinction between the different modes of origin and an estimate of their relative abundance is important if their significance as sources of information on the early history of the solar system is to be clearly understood. (3) Lithic fragments are very useful in attempts to understand the pre- and post-impact history of lunar and meteoritic breccias. They vary from little modified (relative to the apparent original texture), to partly or completely melted and recrystallized lithic fragments.

  12. Foreign Object Damage Behavior of a SiC/SiC Composite at Ambient and Elevated Temperatures

    NASA Technical Reports Server (NTRS)

    Bhatt, Ramakrishna T.; Pereira, J. Michael; Gyekenyesi, John P.; Choi, Sung R.

    2004-01-01

    Foreign object damage (FOD) behavior of a gas-turbine grade SiC/SiC ceramic matrix composite (CMC) was determined at 25 and 1316 C, employing impact velocities from 115 to 440 meters per second by 1.59-mm diameter stell-ball projectiles. Two different types of specimen support were used at each temperature: fully supported and partially supported. For a given temperature, the degree of post-impact strength degradation increased with increasing impact velocity, and was greater in a partially supported configuration than in a fully supported one. The elevated-temperature FOD resistance of the composite, particularly under partially supported loading at higher impact velocities greater than or equal to 350 meters per second, was significantly less than the ambient-temperature counterpart, attributed to a weakening effect of the composite. For fully supported loading, frontal contact stress played a major role in generating composite damage; whereas, for partially supported loading, both frontal contact and backside bending stresses were combined sources of damage generation. The SiC/SiC composite was able to survive higher energy impacts without complete structural failure but suffered more strength affecting damage from low energy impacts than AS800 and SN282 silicon nitrides.

  13. Geomorphology and Geology of the Southwestern Margaritifer Sinus and Argyre Regions of Mars. Part 3: Valley Types and Distribution

    NASA Technical Reports Server (NTRS)

    Parker, T. J.; Pieri, D. C.

    1985-01-01

    Three major valley tapes were identified in the SW Margaritefer Sinus and Argyre regions. Two are restricted to specific geologic units while the third is independent of the geology. The first type (the small valley networks) are found within the channeled and subdued plains unit in the eastern half of the map, in the grooved and channeled plains unit north of Nirgal Vallis, and in scattered instances in the cratered plateau unit north of Argyre. The even smaller valleys just inside Argyre's rim and on the inner slopes of many large craters are not directly related to the processes which formed the small valleys but are a result, instead, of post-impact modification of the crater walls. The second type of valley network is represented by Nirgal Vallis and the similar, shorter continuation of it to the west. This type is found only in the smooth plains material west of Uzboi Vallis in the map area. The third type of valley network is that of the Uzbol-Holden-Ladon valles system. This system is related to catastrophic outflow from Argyre Basin and is topographically rather than geologically controlled.

  14. Autonomous stimulus triggered self-healing in smart structural composites

    NASA Astrophysics Data System (ADS)

    Norris, C. J.; White, J. A. P.; McCombe, G.; Chatterjee, P.; Bond, I. P.; Trask, R. S.

    2012-09-01

    Inspired by the ability of biological systems to sense and autonomously heal damage, this research has successfully demonstrated the first autonomous, stimulus triggered, self-healing system in a structural composite material. Both the sensing and healing mechanisms are reliant on microvascular channels incorporated within a laminated composite material. For the triggering mechanism, a single air filled vessel was pressurized, sealed and monitored. Upon drop weight impact (10 J), delamination and microcrack connectivity between the pressurized vessel and those open to ambient led to a pressure loss which, with the use of a suitable sensor, triggered a pump to deliver a healing agent to the damage zone. Using this autonomous healing approach, near full recovery of post-impact compression strength was achieved (94% on average). A simplified alternative system with healing agent continuously flowing through the vessels, akin to blood flow, was found to offer 100% recovery of the material’s virgin strength. Optical microscopy and ultrasonic C-scanning provided further evidence of large-scale infusion of matrix damage with the healing agent. The successful implementation of this bioinspired technology could substantially enhance the integrity and reliability of aerospace structures, whilst offering benefits through improved performance/weight ratios and extended lifetimes.

  15. Droplet impact on soft viscoelastic surfaces.

    PubMed

    Chen, Longquan; Bonaccurso, Elmar; Deng, Peigang; Zhang, Haibo

    2016-12-01

    In this work, we experimentally investigate the impact of water droplets onto soft viscoelastic surfaces with a wide range of impact velocities. Several impact phenomena, which depend on the dynamic interaction between the droplets and viscoelastic surfaces, have been identified and analyzed. At low We, complete rebound is observed when the impact velocity is between a lower and an upper threshold, beyond which droplets are deposited on the surface after impact. At intermediate We, entrapment of an air bubble inside the impinging droplets is found on soft surfaces, while a bubble entrapment on the surface is observed on rigid surfaces. At high We, partial rebound is only identified on the most rigid surface at We≳92. Rebounding droplets behave similarly to elastic drops rebounding on superhydrophobic surfaces and the impact process is independent of surface viscoelasticity. Further, surface viscoelasticity does not influence drop spreading after impact-as the surfaces behave like rigid surfaces-but it does affect drop recoiling. Also, the postimpact drop oscillation on soft viscoelastic surfaces is influenced by dynamic wettability of these surfaces. Comparing sessile drop oscillation with a damped harmonic oscillator allows us to conclude that surface viscoelasticity affects the damping coefficient and liquid surface tension sets the spring constant of the system.

  16. Cellular characterization of compression induced-damage in live biological samples

    NASA Astrophysics Data System (ADS)

    Bo, Chiara; Balzer, Jens; Hahnel, Mark; Rankin, Sara M.; Brown, Katherine A.; Proud, William G.

    2011-06-01

    Understanding the dysfunctions that high-intensity compression waves induce in human tissues is critical to impact on acute-phase treatments and requires the development of experimental models of traumatic damage in biological samples. In this study we have developed an experimental system to directly assess the impact of dynamic loading conditions on cellular function at the molecular level. Here we present a confinement chamber designed to subject live cell cultures in liquid environment to compression waves in the range of tens of MPa using a split Hopkinson pressure bars system. Recording the loading history and collecting the samples post-impact without external contamination allow the definition of parameters such as pressure and duration of the stimulus that can be related to the cellular damage. The compression experiments are conducted on Mesenchymal Stem Cells from BALB/c mice and the damage analysis are compared to two control groups. Changes in Stem cell viability, phenotype and function are assessed flow cytometry and with in vitro bioassays at two different time points. Identifying the cellular and molecular mechanisms underlying the damage caused by dynamic loading in live biological samples could enable the development of new treatments for traumatic injuries.

  17. Lunar and Venusian radar bright rings

    NASA Technical Reports Server (NTRS)

    Thompson, T. W.; Saunders, R. S.; Weissman, D. E.

    1986-01-01

    Twenty-one lunar craters have radar bright ring appearances which are analogous to eleven complete ring features in the earth-based 12.5 cm observations of Venus. Radar ring diameters and widths for the lunar and Venusian features overlap for sizes from 45 to 100 km. Radar bright areas for the lunar craters are associated with the slopes of the inner and outer rim walls, while level crater floors and level ejecta fields beyond the raised portion of the rim have average radar backscatter. It is proposed that the radar bright areas of the Venusian rings are also associated with the slopes on the rims of craters. The lunar craters have evolved to radar bright rings via mass wasting of crater rim walls and via post-impact flooding of crater floors. Aeolian deposits of fine-grained material on Venusian crater floors may produce radar scattering effects similar to lunar crater floor flooding. These Venusian aeolian deposits may preferentially cover blocky crater floors producing a radar bright ring appearance. It is proposed that the Venusian features with complete bright ring appearances and sizes less than 100 km are impact craters. They have the same sizes as lunar craters and could have evolved to radar bright rings via analogous surface processes.

  18. Impact Foam Testing for Multi-Mission Earth Entry Vehicle Applications

    NASA Technical Reports Server (NTRS)

    Glaab, Louis J.; Agrawal, Paul; Hawbaker, James

    2013-01-01

    Multi-Mission Earth Entry Vehicles (MMEEVs) are blunt-body vehicles designed with the purpose of transporting payloads from outer space to the surface of the Earth. To achieve high-reliability and minimum weight, MMEEVs avoid use of limited-reliability systems, such as parachutes and retro-rockets, instead using built-in impact attenuators to absorb energy remaining at impact to meet landing loads requirements. The Multi-Mission Systems Analysis for Planetary Entry (M-SAPE) parametric design tool is used to facilitate the design of MMEEVs and develop the trade space. Testing was conducted to characterize the material properties of several candidate impact foam attenuators to enhance M-SAPE analysis. In the current effort, two different Rohacell foams were tested to determine their thermal conductivity in support of MMEEV design applications. These applications include thermal insulation during atmospheric entry, impact attenuation, and post-impact thermal insulation in support of thermal soak analysis. Results indicate that for these closed-cell foams, the effect of impact is limited on thermal conductivity due to the venting of the virgin material gas and subsequent ambient air replacement. Results also indicate that the effect of foam temperature is significant compared to data suggested by manufacturer's specifications.

  19. Impact damage to dinocysts from the Late Eocene Chesapeake Bay event

    USGS Publications Warehouse

    Edwards, L.E.; Powars, D.S.

    2003-01-01

    The Chesapeake Bay impact structure, formed by a comet or meteorite that struck the Virginia continental shelf about 35.5 million years ago, is the focus of an extensive coring project by the U.S. Geological Survey and its cooperators. Organic-walled dinocysts recovered from impact-generated deposits in a deep core inside the 85-90 km-wide crater include welded organic clumps and fused, partially melted and bubbled dinocysts unlike any previously observed. Other observed damage to dinocysts consists of breakage, pitting, and folding in various combinations. The entire marine Cretaceous, Paleocene, and Eocene section that was once present at the site has been excavated and redeposited under extreme conditions that include shock, heat, collapse, tsunamis, and airfall. The preserved dinocysts reflect these conditions and, as products of a known impact, may serve as guides for recognizing impact-related deposits elsewhere. Features that are not unique to impacts, such as breakage and folding, may offer new insights into crater-history studies in general, and to the history of the Chesapeake Bay impact structure in particular. Impact-damaged dinocysts also are found sporadically in post-impact deposits and add to the story of continuing erosion and faulting of crater material.

  20. Processing and Synthesis of Pre-Biotic Chemicals in Hypervelocity Impacts

    NASA Technical Reports Server (NTRS)

    Brickerhoff, W. B.; Managadze, G. G.; Chumikov, A. E.; Managadze, N. G.

    2005-01-01

    Hypervelocity impacts (HVIs) may have played a significant role in establishing the initial organic inventory for pre-biotic chemistry on the Earth and other planetary bodies. In addition to the delivery of organic compounds intact to planetary surfaces, generally at velocities below approx.20 km/s, HVIs also enable synthesis of new molecules. The cooling post-impact plasma plumes of HVIs in the interstellar medium (ISM), the protosolar nebula (PSN), and the early solar system comprise pervasive conditions for organic synthesis. Such plasma synthesis (PS) can operate over many length scales (from nm-scale dust to planets) and energy scales (from molecular rearrangement to atomization and recondensation). HVI experiments with the flexibility to probe the highest velocities and distinguish synthetic routes are a high priority to understand the relevance of PS to exobiology. We describe here recent studies of PS at small spatial scales and extremely high velocities with pulsed laser ablation (PLA). PLA can simulate the extreme plasma conditions generated in impacts of dust particles at speeds of up to 100 km/s or more. When applied to carbonaceous solids, new and pre-biotically relevant molecular species are formed with high efficiency [1,2].

  1. Physically disturbed deep-sea macrofauna in the Peru Basin, southeast Pacific, revisited 7 years after the experimental impact

    NASA Astrophysics Data System (ADS)

    Borowski, Christian

    Long-term disturbance effects of a physical disturbance experiment on the benthic macrofauna (>500 μm), with particular emphasis on the dominant Polychaeta, were investigated in connection with the German ATESEPP joint programme in 4150 m depth in the Peru Basin of the tropical southeast (SE) Pacific. The study site was the 10.8 km 2 experimental field of the disturbance and re colonization experiment (DISCOL) conducted in early 1989. This programme had the objective to simulate some of the potential disturbance effects of manganese nodule mining on the bottom-dwelling biota with a towed "plough-harrow" disturber, and subsequently to investigate the resultant community responses with three post-impact samplings during a period of 3 years. Seven years after disturbance, in early 1996, the DISCOL site was revisited, and this study focuses on temporal development of the macrofauna over that extended period. Box core samples obtained during all post-impact expeditions from the disturber tracks ( disturbed treatment) were compared with unploughed sediments from the experimental field ( undisturbed treatment) and with samples from unimpacted sites of the surrounding ( reference treatment). The experiment did not cause the disastrous long-term community changes in the sediment dwelling macrofauna that previously were predicted to follow large-scale disturbances. Abundance recoveries of the macrofaunal taxa were largely terminated after 7 years. Major differences in the faunal compositions at the selected taxonomic levels of higher macrofauna taxa, polychaete families and polychaete species between disturbed and control sites were not observed, but certain disturbance effects remained present over the entire 7-year period: Within-treatment data heterogeneity for the higher macrofauna taxa and the polychaete families was greater in the disturber track samples than in undisturbed and reference treatments. Enhanced heterogeneity was expressed by significantly steeper regression slopes of variance-to-mean ratios of faunal abundances ( p<0.05) and enhanced spatial aggregation at the levels of higher macrofauna taxa and polychaete families. Hurlbert rarefaction E( Sn) and Shannon's diversity index H' calculated in non-standard ways for polychaete species revealed that patterns of diminished "diversity" in the disturbed treatments, which were observed during the later DISCOL period, were still present after 7 years, although the intensity of this signal became weaker. Recent abundance differences between treatments for the Bivalvia, Cumacea and the sigalionid polychaete species Leanira sp. A suggested that unploughed areas from the experimental field possibly were also affected by subtle long-term influences of particle plume settlement caused by the disturber action. A brief comparison with macrofauna abundance data from other ATESEPP sample locations in the Peru Basin revealed highest similarity between the sites located in the manganese nodule province, suggesting that similar disturbance effects can be expected for these areas. Nevertheless, the experimental impact by far did not reach industrial mining impact dimensions and interpretation of the results with regard to commercial mining requires caution.

  2. Effective Practices for Evaluating Education and Public Outreach Programs

    NASA Astrophysics Data System (ADS)

    Wilkerson, S.

    2013-12-01

    Stephanie Baird Wilkerson, PhD Carol Haden EdD Magnolia Consulting,LLC Education and public outreach (EPO) program developers and providers seeking insights regarding effective practices for evaluating EPO activities programs benefit from understanding why evaluation is critical to the success of EPO activities and programs, what data collection methods are appropriate, and how to effectively communicate and report findings. Based on our extensive experience evaluating EPO programs, we will share lessons learned and examples of how these practices play out in actual evaluation studies. EPO program developers, providers, and evaluators must consider several factors that influence which evaluation designs and data collection methods will be most appropriate, given the nature of EPO programs. Effective evaluation practices of EPO programs take into account a program's phase of development, duration, and budget as well as a program's intended outcomes. EPO programs that are just beginning development will have different evaluation needs and priorities than will well-established programs. Effective evaluation practices consider the 'life' of a program with an evaluation design that supports a program's growth through various phases including development, revision and refinement, and completion. It would be premature and inappropriate to expect the attainment of longer-term outcomes of activities during program development phases or early stages of implementation. During program development, EPO providers should clearly define program outcomes that are feasible and appropriate given a program's scope and expected reach. In many respects, this directly relates to the amount of time, or duration, intended audiences participate in EPO programs. As program duration increases so does the likelihood that the program can achieve longer-term outcomes. When choosing which outcomes are reasonable to impact and measure, program duration should be considered. Effective evaluation practices include selecting appropriate data collection methods given a program's duration and corresponding intended outcomes. Data collection methods for programs of short duration might involve simple evaluation activities, whereas programs of longer duration might involve ongoing data collection measures including longitudinal student surveys, implementation logs, student journals, and student achievement measures. During our presentation, we will share examples from our own experience to illustrate how effective evaluation practices can be applied to various EPO programs based on program duration. Irrespective of duration, we find that EPO program developers and providers want both formative feedback to guide improvements and summative feedback on outcomes. More often than not, evaluation budgets for EPO programs are meager at best, yet come with the same information needs and priorities as programs with larger evaluation budgets. So how do program providers get the information they need given their limited funds for evaluation? We will offer several recommendations for helping EPO program providers work with evaluators to become better-informed consumers of evaluation by maximizing evaluation offerings and minimizing costs. During our presentation we also will share examples of communicating and reporting results for EPO program developers, EPO facilitators and practitioners, and funders.

  3. Non-formal educator use of evaluation results.

    PubMed

    Baughman, Sarah; Boyd, Heather H; Franz, Nancy K

    2012-08-01

    Increasing demands for accountability in educational programming have resulted in increasing calls for program evaluation in educational organizations. Many organizations include conducting program evaluations as part of the job responsibilities of program staff. Cooperative Extension is a complex organization offering non-formal educational programs through land grant universities. Many Extension services require non-formal educational program evaluations be conducted by field-based Extension educators. Evaluation research has focused primarily on the efforts of professional, external evaluators. The work of program staff with many responsibilities including program evaluation has received little attention. This study examined how field based Extension educators (i.e. program staff) in four Extension services use the results of evaluations of programs that they have conducted themselves. Four types of evaluation use are measured and explored; instrumental use, conceptual use, persuasive use and process use. Results indicate that there are few programmatic changes as a result of evaluation findings among the non-formal educators surveyed in this study. Extension educators tend to use evaluation results to persuade others about the value of their programs and learn from the evaluation process. Evaluation use is driven by accountability measures with very little program improvement use as measured in this study. Practical implications include delineating accountability and program improvement tasks within complex organizations in order to align evaluation efforts and to improve the results of both. There is some evidence that evaluation capacity building efforts may be increasing instrumental use by educators evaluating their own programs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Guidelines for the Evaluation of Bilingual Education Programs.

    ERIC Educational Resources Information Center

    Cardoza, Desdemona

    Principles of program evaluation research are outlined so that bilingual education program coordinators can conduct methodologically acceptable program evaluations. The three basic principles of evaluation research are: identification of the program participants, definition of the program intervention, and assessment of program effectiveness.…

  5. A psychosocial risk assessment and management framework to enhance response to CBRN terrorism threats and attacks.

    PubMed

    Lemyre, Louise; Clément, Mélanie; Corneil, Wayne; Craig, Lorraine; Boutette, Paul; Tyshenko, Michael; Karyakina, Nataliya; Clarke, Robert; Krewski, Daniel

    2005-01-01

    Evidence in the disaster mental health literature indicates that psychosocial consequences of terrorism are a critical component of chemical, biological, radiological, and nuclear (CBRN) events, both at the clinical level and the normal behavioral and emotional levels. Planning for such psychosocial aspects should be an integral part of emergency preparedness. As Canada and other countries build the capacity to prevent, mitigate, and manage CBRN threats and events, it is important to recognize the range of social, psychological, emotional, spiritual, behavioral, and cognitive factors that may affect victims and their families, communities, children, the elderly, responders, decision makers, and others at all phases of terrorism, from threat to post-impact recovery. A structured process to assist CBRN emergency planners, decision makers, and responders in identifying psychosocial risks, vulnerable populations, resources, and interventions at various phases of a CBRN event to limit negative psychosocial impacts and promote resilience and adaptive responses is the essence of our psychosocial risk assessment and management (P-RAM) framework. This article presents the evidence base and conceptual underpinnings of the framework, the principles underlying its design, its key elements, and its use in the development of decision tools for responders, planners, decision makers, and the general public to better assess and manage psychosocial aspects of CBRN threats or attacks.

  6. Zhamanshin astrobleme provides evidence for carbonaceous chondrite and post-impact exchange between ejecta and Earth's atmosphere.

    PubMed

    Magna, Tomáš; Žák, Karel; Pack, Andreas; Moynier, Frédéric; Mougel, Bérengère; Peters, Stefan; Skála, Roman; Jonášová, Šárka; Mizera, Jiří; Řanda, Zdeněk

    2017-08-09

    Chemical fingerprints of impacts are usually compromised by extreme conditions in the impact plume, and the contribution of projectile matter to impactites does not often exceed a fraction of per cent. Here we use chromium and oxygen isotopes to identify the impactor and impact-plume processes for Zhamanshin astrobleme, Kazakhstan. ε 54 Cr values up to 1.54 in irghizites, part of the fallback ejecta, represent the 54 Cr-rich extremity of the Solar System range and suggest a CI-like chondrite impactor. Δ 17 O values as low as -0.22‰ in irghizites, however, are incompatible with a CI-like impactor. We suggest that the observed 17 O depletion in irghizites relative to the terrestrial range is caused by partial isotope exchange with atmospheric oxygen (Δ 17 O = -0.47‰) following material ejection. In contrast, combined Δ 17 O-ε 54 Cr data for central European tektites (distal ejecta) fall into the terrestrial range and neither impactor fingerprint nor oxygen isotope exchange with the atmosphere are indicated.Identifying the original impactor from craters remains challenging. Here, the authors use chromium and oxygen isotopes to indicate that the Zhamanshin astrobleme impactor was a carbonaceous chrondrite by demonstrating that depleted 17O values are due to exchange with atmospheric oxygen.

  7. The Collision of Comet Shoemaker-Levy 9 and Jupiter

    NASA Astrophysics Data System (ADS)

    Noll, Keith S.; Weaver, Harold A.; Feldman, Paul D.

    2006-11-01

    Participants; Preface; 1. The orbital motion and impact circumstances of Comet Shoemaker-Levy 9 Paul W. Chodas and Donald K. Yeomans; 2. Observational constraints on the composition and nature of Comet D/Shoemaker-Levy 9 Jacques Crovisier; 3. Tidal breakup of the nucleus of Comet Shoemaker-Levy 9 Zdenek Sekanina; 4. Earth-based observations of impact phenomena Philip D. Nicholson; 5. HST imaging of Jupiter shortly after each impact: plumes and fresh sites Heidi B. Hammel; 6. Galileo observations of the impacts Clark R. Chapman; 7. Models of fragment penetration and fireball evolution David A. Crawford; 8. Entry and fireball models vs. observations: what have we learned? Mordecai-Mark Mac Low; 9. Dynamics and chemistry of SL9 plumes Kevin Zahnle; 10. Chemistry induced by the impacts: observations Emmanuel Lellouch; 11. SL9 impact chemistry: long-term photochemical evolution Julianne I. Moses; 12. Particulate matter in Jupiter's atmosphere from the impacts of Comet P/Shoemaker-Levy 9 Robert A. West; 13. Jupiter's post-impact atmospheric thermal response Barney J. Conrath; 14. Growth and dispersion of the Shoemaker-Levy 9 impact features from HST imaging Reta F. Beebe; 15. Waves from the Shoemaker-Levy 9 impacts Andrew P. Ingersoll and Hiroo Kanamori; 16. Jovian magnetospheric and auroral effects of the SL9 impacts Wing-Huen Ip.

  8. Asteroid Secular Dynamics: Ceres’ Fingerprint Identified

    NASA Astrophysics Data System (ADS)

    Novaković, Bojan; Maurel, Clara; Tsirvoulis, Georgios; Knežević, Zoran

    2015-07-01

    Here we report on the significant role of a so far overlooked dynamical aspect, namely, a secular resonance between the dwarf planet Ceres and other asteroids. We demonstrate that this type of secular resonance can be the dominant dynamical factor in certain regions of the main asteroid belt. Specifically, we performed a dynamical analysis of the asteroids belonging to the (1726) Hoffmeister family. To identify which dynamical mechanisms are actually at work in this part of the main asteroid belt, i.e., to isolate the main perturber(s), we study the evolution of this family in time. The study is accomplished using numerical integrations of test particles performed within different dynamical models. The obtained results reveal that the post-impact evolution of the Hoffmeister asteroid family is a direct consequence of the nodal secular resonance with Ceres. This leads us to the conclusion that similar effects must exist in other parts of the asteroid belt. In this respect, the obtained results shed light on an important and entirely new aspect of the long-term dynamics of small bodies. Ceres’ fingerprint in asteroid dynamics, expressed through the discovered secular resonance effect, completely changes our understanding of the way in which perturbations by Ceres-like objects affect the orbits of nearby bodies.

  9. Tethys Eyes Saturn

    NASA Image and Video Library

    2015-06-15

    The two large craters on Tethys, near the line where day fades to night, almost resemble two giant eyes observing Saturn. The location of these craters on Tethys' terminator throws their topography into sharp relief. Both are large craters, but the larger and southernmost of the two shows a more complex structure. The angle of the lighting highlights a central peak in this crater. Central peaks are the result of the surface reacting to the violent post-impact excavation of the crater. The northern crater does not show a similar feature. Possibly the impact was too small to form a central peak, or the composition of the material in the immediate vicinity couldn't support the formation of a central peak. In this image Tethys is significantly closer to the camera, while the planet is in the background. Yet the moon is still utterly dwarfed by the giant Saturn. This view looks toward the anti-Saturn side of Tethys. North on Tethys is up and rotated 42 degrees to the right. The image was taken in visible light with the Cassini spacecraft wide-angle camera on April 11, 2015. The view was obtained at a distance of approximately 75,000 miles (120,000 kilometers) from Tethys. Image scale at Tethys is 4 miles (7 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/pia18318

  10. Impactor core disruption by high-energy planetary collisions

    NASA Astrophysics Data System (ADS)

    Landeau, M.; Phillips, D.; Deguen, R.; Neufeld, J.; Dalziel, S.; Olson, P.

    2017-12-01

    Understanding the fate of impactor cores during large planetary collisions is key for predicting metal-silicate equilibration during Earth's accretion. Accretion models and geochemical observations indicate that much of Earth's mass accreted through high-energy impacts between planetary embryos already differentiated into a metallic core and a silicate mantle. Previous studies on core formation assume that the metallic core of the impactor is left intact by the impact, but it mixes with silicates during the post-impact fall in the magma ocean. Recent impact simulations, however, suggest that the impact cratering process induces significant core disruption and metal-silicate mixing. Unlike existing impact simulations, experiments can produce turbulence, a key ingredient to investigate disruption of the impactor core. Here we use laboratory experiments where a volume of salt solution (representing the impactor core) vertically impacts a pool of water (representing the magma ocean) to quantify impact-induced mixing between the impactor and the target as a function of impact velocity, impactor size and density difference. We find that the ratio between the impactor inertia and its weight controls mixing. Extrapolated to planetary accretion, our results suggest that the impact process induces no significant mixing for impactors of comparable size as the protoplanet whereas the impactor core is highly disrupted by impacts involving impactors much smaller than the protoplanet.

  11. Open hole and postimpact compressive fatigue of stitched and unstitched carbon-epoxy composites

    NASA Technical Reports Server (NTRS)

    Portanova, Marc A.; Poe, Clarence C.; Whitcomb, John D.

    1992-01-01

    The performance is studied of a stitched uniweave fabric composite and that of a toughened tape composite. The effects of stitching on compression fatigue life are addressed. Post impact compression fatigue and open hole fatigue tests were run on an AS4/3501-6 uniweave with stitching and a toughened IM7/8551-7 tape without stitching. Stitching was found to increase the thickness and consequently the weight of the composite material. The two materials were compared on an equal carbon content basis as well as on an equal weight basis. The excess thickness in the stitched uniweave composite was responsible for the lower fatigue life, on an equal carbon basis, compared to the toughened resin tape composite. Comparison of fatigue lives on an equal carbon content basis indicated that puncture or crimp type damage from stitching has very little effect on compression failure. Post impact fatigue test showed that although the damage area in the stitched uniweave composite was twice that of the toughened tape composite, the fatigue lives of the stitched composite were significantly longer than those of the toughened composite. Thus, it appears that the increase in thickness from stitching is much more of a penalty than crimped fibers or puncture type damage from stitching.

  12. Microbial abundance in the deep subsurface of the Chesapeake Bay impact crater: Relationship to lithology and impact processes

    USGS Publications Warehouse

    Cockell, Charles S.; Gronstal, Aaron L.; Voytek, Mary A.; Kirshtein, Julie D.; Finster, Kai; Sanford, Ward E.; Glamoclija, Mihaela; Gohn, Gregroy S.; Powars, David S.; Horton, J. Wright

    2009-01-01

    Asteroid and comet impact events are known to cause profound disruption to surface ecosystems. The aseptic collection of samples throughout a 1.76-km-deep set of cores recovered from the deep subsurface of the Chesapeake Bay impact structure has allowed the study of the subsurface biosphere in a region disrupted by an impactor. Microbiological enumerations suggest the presence of three major microbiological zones. The upper zone (127–867 m) is characterized by a logarithmic decline in microbial abundance from the surface through the postimpact section of Miocene to Upper Eocene marine sediments and across the transition into the upper layers of the impact tsunami resurge sediments and sediment megablocks. In the middle zone (867–1397 m) microbial abundances are below detection. This zone is predominantly quartz sand, primarily composed of boulders and blocks, and it may have been mostly sterilized by the thermal pulse delivered during impact. No samples were collected from the large granite block (1096–1371 m). The lowest zone (below 1397 m) of increasing microbial abundance coincides with a region of heavily impact-fractured, hydraulically conductive suevite and fractured schist. These zones correspond to lithologies influenced by impact processes. Our results yield insights into the influence of impacts on the deep subsurface biosphere.

  13. Ice Particle Impacts on a Moving Wedge

    NASA Technical Reports Server (NTRS)

    Vargas, Mario; Struk, Peter M.; Kreeger, Richard E.; Palacios, Jose; Iyer, Kaushik A.; Gold, Robert E.

    2014-01-01

    This work presents the results of an experimental study of ice particle impacts on a moving wedge. The experiment was conducted in the Adverse Environment Rotor Test Stand (AERTS) facility located at Penn State University. The wedge was placed at the tip of a rotating blade. Ice particles shot from a pressure gun intercepted the moving wedge and impacted it at a location along its circular path. The upward velocity of the ice particles varied from 7 to 12 meters per second. Wedge velocities were varied from 0 to 120 meters per second. Wedge angles tested were 0 deg, 30 deg, 45 deg, and 60 deg. High speed imaging combined with backlighting captured the impact allowing observation of the effect of velocity and wedge angle on the impact and the post-impact fragment behavior. It was found that the pressure gun and the rotating wedge could be synchronized to consistently obtain ice particle impacts on the target wedge. It was observed that the number of fragments increase with the normal component of the impact velocity. Particle fragments ejected immediately after impact showed velocities higher than the impact velocity. The results followed the major qualitative features observed by other researchers for hailstone impacts, even though the reduced scale size of the particles used in the present experiment as compared to hailstones was 4:1.

  14. Constructional Volcanic Edifices on Mercury: Candidates and Hypotheses of Formation

    NASA Astrophysics Data System (ADS)

    Wright, Jack; Rothery, David A.; Balme, Matthew R.; Conway, Susan J.

    2018-04-01

    Mercury, a planet with a predominantly volcanic crust, has perplexingly few, if any, constructional volcanic edifices, despite their common occurrence on other solar system bodies with volcanic histories. Using image and topographical data from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, we describe two small (<15-km diameter) prominences with shallow summit depressions associated with volcanically flooded impact features. We offer both volcanic and impact-related interpretations for their formation, and then compare these landforms with volcanic features on Earth and the Moon. Though we cannot definitively conclude that these landforms are volcanic, the paucity of constructional volcanic edifices on Mercury is intriguing in itself. We suggest that this lack is because volcanic eruptions with sufficiently low eruption volumes, rates, and flow lengths, suitable for edifice construction, were highly spatiotemporally restricted during Mercury's geological history. We suggest that volcanic edifices may preferentially occur in association with late-stage, postimpact effusive volcanic deposits. The European Space Agency/Japan Aerospace Exploration Agency BepiColombo mission to Mercury will be able to investigate further our candidate volcanic edifices; search for other, as-yet unrecognized edifices beneath the detection limits of MESSENGER data; and test our hypothesis that edifice construction is favored by late-stage, low-volume effusive eruptions.

  15. Open hole and post-impact compression fatigue of stitched and unstitched carbon/epoxy composites

    NASA Technical Reports Server (NTRS)

    Portanova, M. A.; Poe, C. C., Jr.; Whitcomb, John D.

    1990-01-01

    The performance is studied of a stitched uniweave fabric composite and that of a toughened tape composite. The effects of stitching on compression fatigue life are addressed. Post impact compression fatigue and open hole fatigue tests were run on an AS4/3501-6 uniweave with stitching and a toughened IM7/8551-7 tape without stitching. Stitching was found to increase the thickness and consequently the weight of the composite material. The two materials were compared on an equal carbon content basis as well as on an equal weight basis. The excess thickness in the stitched uniweave composite was responsible for the lower fatigue life, on an equal carbon basis, compared to the toughened resin tape composite. Comparison of fatigue lives on an equal carbon content basis indicated that puncture or crimp type damage from stitching has very little effect on compression failure. Post impact fatigue test showed that although the damage area in the stitched uniweave composite was twice that of the toughened tape composite, the fatigue lives of the stitched composite were significantly longer than those of the toughened composite. Thus, it appears that the increase in thickness from stitching is much more of a penalty than crimped fibers or puncture type damage from stitching.

  16. Raman spectroscopy of shocked gypsum from a meteorite impact crater

    NASA Astrophysics Data System (ADS)

    Brolly, Connor; Parnell, John; Bowden, Stephen

    2017-07-01

    Impact craters and associated hydrothermal systems are regarded as sites within which life could originate on Earth, and on Mars. The Haughton impact crater, one of the most well preserved craters on Earth, is abundant in Ca-sulphates. Selenite, a transparent form of gypsum, has been colonized by viable cyanobacteria. Basement rocks, which have been shocked, are more abundant in endolithic organisms, when compared with un-shocked basement. We infer that selenitic and shocked gypsum are more suitable for microbial colonization and have enhanced habitability. This is analogous to many Martian craters, such as Gale Crater, which has sulphate deposits in a central layered mound, thought to be formed by post-impact hydrothermal springs. In preparation for the 2020 ExoMars mission, experiments were conducted to determine whether Raman spectroscopy can distinguish between gypsum with different degrees of habitability. Ca-sulphates were analysed using Raman spectroscopy and results show no significant statistical difference between gypsum that has experienced shock by meteorite impact and gypsum, which has been dissolved and re-precipitated as an evaporitic crust. Raman spectroscopy is able to distinguish between selenite and unaltered gypsum. This shows that Raman spectroscopy can identify more habitable forms of gypsum, and demonstrates the current capabilities of Raman spectroscopy for the interpretation of gypsum habitability.

  17. A hydrothermal system associated with the Siljan impact structure, Sweden--implications for the search for fossil life on Mars.

    PubMed

    Hode, Tomas; von Dalwigk, Ilka; Broman, Curt

    2003-01-01

    The Siljan ring structure (368 +/- 1.1 Ma) is the largest known impact structure in Europe. It isa 65-km-wide, eroded, complex impact structure, displaying several structural units, including a central uplifted region surrounded by a ring-shaped depression. Associated with the impact crater are traces of a post-impact hydrothermal system indicated by precipitated and altered hydrothermal mineral assemblages. Precipitated hydrothermal minerals include quartz veins and breccia fillings associated with granitic rocks at the outer margin of the central uplift, and calcite, fluorite, galena, and sphalerite veins associated with Paleozoic carbonate rocks located outside the central uplift. Two-phase water/gas and oil/gas inclusions in calcite and fluorite display homogenization temperatures between 75 degrees C and 137 degrees C. With an estimated erosional unloading of approximately 1 km, the formation temperatures were probably not more than 10-15 degrees C higher. Fluid inclusion ice-melting temperatures indicate a very low salt content, reducing the probability that the mineralization was precipitated during the Caledonian Orogeny. Our findings suggest that large impacts induce low-temperature hydrothermal systems that may be habitats for thermophilic organisms. Large impact structures on Mars may therefore be suitable targets in the search for fossil thermophilic organisms.

  18. Steps to a HealthierUS Cooperative Agreement Program: foundational elements for program evaluation planning, implementation, and use of findings.

    PubMed

    MacDonald, Goldie; Garcia, Danyael; Zaza, Stephanie; Schooley, Michael; Compton, Don; Bryant, Terry; Bagnol, Lulu; Edgerly, Cathy; Haverkate, Rick

    2006-01-01

    The Steps to a HealthierUS Cooperative Agreement Program (Steps Program) enables funded communities to implement chronic disease prevention and health promotion efforts to reduce the burden of diabetes, obesity, asthma, and related risk factors. At both the national and community levels, investment in surveillance and program evaluation is substantial. Public health practitioners engaged in program evaluation planning often identify desired outcomes, related indicators, and data collection methods but may pay only limited attention to an overarching vision for program evaluation among participating sites. We developed a set of foundational elements to provide a vision of program evaluation that informs the technical decisions made throughout the evaluation process. Given the diversity of activities across the Steps Program and the need for coordination between national- and community-level evaluation efforts, our recommendations to guide program evaluation practice are explicit yet leave room for site-specific context and needs. Staff across the Steps Program must consider these foundational elements to prepare a formal plan for program evaluation. Attention to each element moves the Steps Program closer to well-designed and complementary plans for program evaluation at the national, state, and community levels.

  19. A Comparison of the SOCIT and DebriSat Experiments

    NASA Technical Reports Server (NTRS)

    Ausay, Erick; Blake, Brandon; Boyle, Colleen; Cornejo, Alex; Horn, Alexa; Palma, Kirsten; Pistella, Frank; Sato, Taishi; Todd, Naromi; Zimmerman, Jeffrey; hide

    2017-01-01

    This paper explores the differences between, and shares the lessons learned from, two hypervelocity impact experiments critical to the update of orbital debris environment models. The procedures and processes of the fourth Satellite Orbital Debris Characterization Impact Test (SOCIT) were analyzed and related to the ongoing DebriSat experiment. SOCIT was the first hypervelocity impact test designed specifically for satellites in Low Earth Orbit (LEO). It targeted a 1960's U.S. Navy satellite, from which data was obtained to update pre-existing NASA and DOD breakup models. DebriSat is a comprehensive update to these satellite breakup models- necessary since the material composition and design of satellites have evolved from the time of SOCIT. Specifically, DebriSat utilized carbon fiber, a composite not commonly used in satellites during the construction of the US Navy Transit satellite used in SOCIT. Although DebriSat is an ongoing activity, multiple points of difference are drawn between the two projects. Significantly, the hypervelocity tests were conducted with two distinct satellite models and test configurations, including projectile and chamber layout. While both hypervelocity tests utilized soft catch systems to minimize fragment damage to its post-impact shape, SOCIT only covered 65% of the projected area surrounding the satellite, whereas, DebriSat was completely surrounded cross-range and downrange by the foam panels to more completely collect fragments. Furthermore, utilizing lessons learned from SOCIT, DebriSat's post-impact processing varies in methodology (i.e., fragment collection, measurement, and characterization). For example, fragment sizes were manually determined during the SOCIT experiment, while DebriSat utilizes automated imaging systems for measuring fragments, maximizing repeatability while minimizing the potential for human error. In addition to exploring these variations in methodologies and processes, this paper also presents the challenges DebriSat has encountered thus far and how they were addressed. Accomplishing DebriSat's goal of collecting 90% of the debris, which constitutes well over 100,000 fragments, required addressing many challenges stemming from the very large number of fragments. One of these challenges arose in identifying the foam-embedded fragments. DebriSat addressed this by X-raying all of the panels once the loose debris were removed, and applying a detection algorithm developed in-house to automate the embedded fragment identification process. It is easy to see how the amount of data being compiled would be outstanding. Creating an efficient way to catalog each fragment, as well as archiving the data for reproducibility also posed a great challenge for DebriSat. Barcodes to label each fragment were introduced with the foresight that once the characterization process began, the datasheet for each fragment would have to be accessed again quickly and efficiently. The DebriSat experiment has benefited significantly by leveraging lessons learned from the SOCIT experiment along with the technological advancements that have occurred during the time between the experiments. The two experiments represent two ages of satellite technology and, together, demonstrate the continuous efforts to improve the experimental techniques for fragmentation debris characterization.

  20. Maximizing the Impact of Program Evaluation: A Discrepancy-Based Process for Educational Program Evaluation.

    ERIC Educational Resources Information Center

    Cantor, Jeffrey A.

    This paper describes a formative/summative process for educational program evaluation, which is appropriate for higher education programs and is based on M. Provus' Discrepancy Evaluation Model and the principles of instructional design. The Discrepancy Based Methodology for Educational Program Evaluation facilitates systematic and detailed…

  1. The Evaluation Handbook: Guidelines for Evaluating Dropout Prevention Programs.

    ERIC Educational Resources Information Center

    Smink, Jay; Stank, Peg

    This manual, developed in an effort to take the mysticism out of program evaluation, discusses six phases of the program evaluation process. The introduction discusses reasons for evaluation, process and outcome evaluation, the purpose of the handbook, the evaluation process, and the Sequoia United School District Dropout Prevention Program. Phase…

  2. Curated Collections for Educators: Five Key Papers about Program Evaluation.

    PubMed

    Thoma, Brent; Gottlieb, Michael; Boysen-Osborn, Megan; King, Andrew; Quinn, Antonia; Krzyzaniak, Sara; Pineda, Nicolas; Yarris, Lalena M; Chan, Teresa

    2017-05-04

    The evaluation of educational programs has become an expected part of medical education. At some point, all medical educators will need to critically evaluate the programs that they deliver. However, the evaluation of educational programs requires a very different skillset than teaching. In this article, we aim to identify and summarize key papers that would be helpful for faculty members interested in exploring program evaluation. In November of 2016, the 2015-2016 Academic life in emergency medicine (ALiEM) Faculty Incubator program highlighted key papers in a discussion of program evaluation. This list of papers was augmented with suggestions by guest experts and by an open call on Twitter. This resulted in a list of 30 papers on program evaluation. Our authorship group then engaged in a process akin to a Delphi study to build consensus on the most important papers about program evaluation for medical education faculty. We present our group's top five most highly rated papers on program evaluation. We also summarize these papers with respect to their relevance to junior medical education faculty members and faculty developers. Program evaluation is challenging. The described papers will be informative for junior faculty members as they aim to design literature-informed evaluations for their educational programs.

  3. Curated Collections for Educators: Five Key Papers about Program Evaluation

    PubMed Central

    Gottlieb, Michael; Boysen-Osborn, Megan; King, Andrew; Quinn, Antonia; Krzyzaniak, Sara; Pineda, Nicolas; Yarris, Lalena M; Chan, Teresa

    2017-01-01

    The evaluation of educational programs has become an expected part of medical education. At some point, all medical educators will need to critically evaluate the programs that they deliver. However, the evaluation of educational programs requires a very different skillset than teaching. In this article, we aim to identify and summarize key papers that would be helpful for faculty members interested in exploring program evaluation. In November of 2016, the 2015-2016 Academic life in emergency medicine (ALiEM) Faculty Incubator program highlighted key papers in a discussion of program evaluation. This list of papers was augmented with suggestions by guest experts and by an open call on Twitter. This resulted in a list of 30 papers on program evaluation. Our authorship group then engaged in a process akin to a Delphi study to build consensus on the most important papers about program evaluation for medical education faculty. We present our group’s top five most highly rated papers on program evaluation. We also summarize these papers with respect to their relevance to junior medical education faculty members and faculty developers. Program evaluation is challenging. The described papers will be informative for junior faculty members as they aim to design literature-informed evaluations for their educational programs. PMID:28589073

  4. The Spiral-Interactive Program Evaluation Model.

    ERIC Educational Resources Information Center

    Khaleel, Ibrahim Adamu

    1988-01-01

    Describes the spiral interactive program evaluation model, which is designed to evaluate vocational-technical education programs in secondary schools in Nigeria. Program evaluation is defined; utility oriented and process oriented models for evaluation are described; and internal and external evaluative factors and variables that define each…

  5. A Qualitative Program Evaluation of a Structured Leadership Mentoring Program at a Large Aerospace Corporation

    ERIC Educational Resources Information Center

    Teller, Romney P.

    2011-01-01

    The researcher utilized a qualitative approach to conduct a program evaluation of the organization where he is employed. The study intended to serve as a program evaluation for the structured in-house mentoring program at a large aerospace corporation (A-Corp). This program evaluation clarified areas in which the current mentoring program is…

  6. Interfacing theories of program with theories of evaluation for advancing evaluation practice: Reductionism, systems thinking, and pragmatic synthesis.

    PubMed

    Chen, Huey T

    2016-12-01

    Theories of program and theories of evaluation form the foundation of program evaluation theories. Theories of program reflect assumptions on how to conceptualize an intervention program for evaluation purposes, while theories of evaluation reflect assumptions on how to design useful evaluation. These two types of theories are related, but often discussed separately. This paper attempts to use three theoretical perspectives (reductionism, systems thinking, and pragmatic synthesis) to interface them and discuss the implications for evaluation practice. Reductionism proposes that an intervention program can be broken into crucial components for rigorous analyses; systems thinking view an intervention program as dynamic and complex, requiring a holistic examination. In spite of their contributions, reductionism and systems thinking represent the extreme ends of a theoretical spectrum; many real-world programs, however, may fall in the middle. Pragmatic synthesis is being developed to serve these moderate- complexity programs. These three theoretical perspectives have their own strengths and challenges. Knowledge on these three perspectives and their evaluation implications can provide a better guide for designing fruitful evaluations, improving the quality of evaluation practice, informing potential areas for developing cutting-edge evaluation approaches, and contributing to advancing program evaluation toward a mature applied science. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. A Culturally Responsive Evaluation Approach Applied to the Talent Development School-to-Career Intervention Program

    ERIC Educational Resources Information Center

    Manswell-Butty, Jo-Anne L.; Reid, Malva Daniel; LaPoint, Velma

    2004-01-01

    Program evaluation has long been used to reveal program characteristics, merits, and challenges. While providing information about program effectiveness, evaluations can also ensure understanding of program outcomes, efficiency, and quality. Furthermore, evaluations can analyze and examine a program's political and social environment as well as…

  8. The State of Evaluation in Internal Medicine Residency

    PubMed Central

    Holmboe, Eric; Beasley, Brent W.

    2008-01-01

    Background There are no nationwide data on the methods residency programs are using to assess trainee competence. The Accreditation Council for Graduate Medical Education (ACGME) has recommended tools that programs can use to evaluate their trainees. It is unknown if programs are adhering to these recommendations. Objective To describe evaluation methods used by our nation’s internal medicine residency programs and assess adherence to ACGME methodological recommendations for evaluation. Design Nationwide survey. Participants All internal medicine programs registered with the Association of Program Directors of Internal Medicine (APDIM). Measurements Descriptive statistics of programs and tools used to evaluate competence; compliance with ACGME recommended evaluative methods. Results The response rate was 70%. Programs were using an average of 4.2–6.0 tools to evaluate their trainees with heavy reliance on rating forms. Direct observation and practice and data-based tools were used much less frequently. Most programs were using at least 1 of the Accreditation Council for Graduate Medical Education (ACGME)’s “most desirable” methods of evaluation for all 6 measures of trainee competence. These programs had higher support staff to resident ratios than programs using less desirable evaluative methods. Conclusions Residency programs are using a large number and variety of tools for evaluating the competence of their trainees. Most are complying with ACGME recommended methods of evaluation especially if the support staff to resident ratio is high. PMID:18612734

  9. Lessons from the trenches: meeting evaluation challenges in school health education.

    PubMed

    Young, Michael; Denny, George; Donnelly, Joseph

    2012-11-01

    Those involved in school health education programs generally believe that health-education programs can play an important role in helping young people make positive health decisions. Thus, it is to document the effects of such programs through rigorous evaluations published in peer-reviewed journals. This paper helps the reader understand the context of school health program evaluation, examines several problems and challenges, shows how problems can often be fixed, or prevented, and demonstrates ways in which challenges can be met. A number of topics are addressed, including distinguishing between curricula evaluation and evaluation of outcomes, types of evaluation, identifying stakeholders in school health evaluation, selection of a program evaluator, recruiting participants, design issues, staff training, parental consent, instrumentation, program implementation and treatment fidelity, participant retention, data collection, data analysis and interpretation, presentation of results, and manuscript preparation and submission. Although there is a lack of health-education program evaluation, rigorous evaluations that have been conducted have, at least in some cases, led to wider dissemination of effective programs. These suggestions will help those interested in school health education understand the importance of evaluation and will provide important guidelines for those conducting evaluations of school health-education programs. © 2012, American School Health Association.

  10. Feedback Improvement in Automatic Program Evaluation Systems

    ERIC Educational Resources Information Center

    Skupas, Bronius

    2010-01-01

    Automatic program evaluation is a way to assess source program files. These techniques are used in learning management environments, programming exams and contest systems. However, use of automated program evaluation encounters problems: some evaluations are not clear for the students and the system messages do not show reasons for lost points.…

  11. Use of program logic models in the Southern Rural Access Program evaluation.

    PubMed

    Pathman, Donald; Thaker, Samruddhi; Ricketts, Thomas C; Albright, Jennifer B

    2003-01-01

    The Southern Rural Access Program (SRAP) evaluation team used program logic models to clarify grantees' activities, objectives, and timelines. This information was used to benchmark data from grantees' progress reports to assess the program's successes. This article presents a brief background on the use of program logic models--essentially charts or diagrams specifying a program's planned activities, objectives, and goals--for evaluating and managing a program. It discusses the structure of the logic models chosen for the SRAP and how the model concept was introduced to the grantees to promote acceptance and use of the models. The article describes how the models helped clarify the program's objectives and helped lead agencies plan and manage the many program initiatives and subcontractors in their states. Models also provided a framework for grantees to report their progress to the National Program Office and evaluators and promoted the evaluators' visibility and acceptance by the grantees. Program logics, however, increased grantees' reporting requirements and demanded substantial time of the evaluators. Program logic models, on balance, proved their merit in the SRAP through their contributions to its management and evaluation and by providing a better understanding of the program's initiatives, successes, and potential impact.

  12. A novel resident-as-teacher training program to improve and evaluate obstetrics and gynecology resident teaching skills.

    PubMed

    Ricciotti, Hope A; Dodge, Laura E; Head, Julia; Atkins, K Meredith; Hacker, Michele R

    2012-01-01

    Residents play a significant role in teaching, but formal training, feedback, and evaluation are needed. Our aims were to assess resident teaching skills in the resident-as-teacher program, quantify correlations of faculty evaluations with resident self-evaluations, compare resident-as-teacher evaluations with clinical evaluations, and evaluate the resident-as-teacher program. The resident-as-teacher training program is a simulated, videotaped teaching encounter with a trained medical student and standardized teaching evaluation tool. Evaluations from the resident-as-teacher training program were compared to evaluations of resident teaching done by faculty, residents, and medical students from the clinical setting. Faculty evaluation of resident teaching skills in the resident-as-teacher program showed a mean total score of 4.5 ± 0.5 with statistically significant correlations between faculty assessment and resident self-evaluations (r = 0.47; p < 0.001). However, resident self-evaluation of teaching skill was lower than faculty evaluation (mean difference: 0.4; 95% CI 0.3-0.6). When compared to the clinical setting, resident-as-teacher evaluations were significantly correlated with faculty and resident evaluations, but not medical student evaluations. Evaluations from both the resident-as-teacher program and the clinical setting improved with duration of residency. The resident-as-teacher program provides a method to train, give feedback, and evaluate resident teaching.

  13. Program Evaluation of a Special Education Day School for Conduct Problem Adolescents.

    ERIC Educational Resources Information Center

    Maher, Charles A.

    1981-01-01

    Describes a procedure for program evaluation of a special education day school. The procedure enables a program evaluator to: (1) identify priority evaluation information needs of a school staff, (2) involve those persons in evaluation design and implementation, and (3) determine the utility of the evaluation for program decision-making purposes.…

  14. Evaluating programs that address ideological issues: ethical and practical considerations for practitioners and evaluators.

    PubMed

    Lieberman, Lisa D; Fagen, Michael C; Neiger, Brad L

    2014-03-01

    There are important practical and ethical considerations for organizations in conducting their own, or commissioning external, evaluations and for both practitioners and evaluators, when assessing programs built on strongly held ideological or philosophical approaches. Assessing whether programs "work" has strong political, financial, and/or moral implications, particularly when expending public dollars, and may challenge objectivity about a particular program or approach. Using a case study of the evaluation of a school-based abstinence-until-marriage program, this article discusses the challenges, lessons learned, and ethical responsibilities regarding decisions about evaluation, specifically associated with ideologically driven programs. Organizations should consider various stakeholders and views associated with their program to help identify potential pitfalls in evaluation. Once identified, the program or agency needs to carefully consider its answers to two key questions: Do they want the answer and are they willing to modify the program? Having decided to evaluate, the choice of evaluator is critical to assuring that ethical principles are maintained and potential skepticism or criticism of findings can be addressed appropriately. The relationship between program and evaluator, including agreements about ownership and eventual publication and/or promotion of data, should be addressed at the outset. Programs and organizations should consider, at the outset, their ethical responsibility when findings are not expected or desired. Ultimately, agencies, organizations, and programs have an ethical responsibility to use their data to provide health promotion programs, whether ideologically founded or not, that appropriately and effectively address the problems they seek to solve.

  15. Educational Evaluation: Key Characteristics. ACER Research Series No. 102.

    ERIC Educational Resources Information Center

    Maling-Keepes, Jillian

    A set of 13 key characteristics is presented as a framework for educational evaluation studies: (1) program's stage of development when evaluator is appointed; (2) program's openness to revision; (3) program uniformity from site to site; (4) specificity of program objectives; (5) evaluator's independence; (6) evaluator's orientation to value…

  16. 42 CFR 491.11 - Program evaluation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Program evaluation. 491.11 Section 491.11 Public... Certification; and FQHCs Conditions for Coverage § 491.11 Program evaluation. (a) The clinic or center carries out, or arranges for, an annual evaluation of its total program. (b) The evaluation includes review of...

  17. Evaluating Educational Programs. ERIC Digest Series Number EA 54.

    ERIC Educational Resources Information Center

    Beswick, Richard

    In this digest, readers are introduced to the scope of instructional program evaluation and evaluators' changing roles in school districts. A program evaluation measures outcomes based on student-attainment goals, implementation levels, and external factors such as budgetary restraints and community support. Instructional program evaluation may be…

  18. Developing Your Evaluation Plans: A Critical Component of Public Health Program Infrastructure.

    PubMed

    Lavinghouze, S Rene; Snyder, Kimberly

    A program's infrastructure is often cited as critical to public health success. The Component Model of Infrastructure (CMI) identifies evaluation as essential under the core component of engaged data. An evaluation plan is a written document that describes how to monitor and evaluate a program, as well as how to use evaluation results for program improvement and decision making. The evaluation plan clarifies how to describe what the program did, how it worked, and why outcomes matter. We use the Centers for Disease Control and Prevention's (CDC) "Framework for Program Evaluation in Public Health" as a guide for developing an evaluation plan. Just as using a roadmap facilitates progress on a long journey, a well-written evaluation plan can clarify the direction your evaluation takes and facilitate achievement of the evaluation's objectives.

  19. Evaluation of Career Guidance Programs: Models, Methods, and Microcomputers. Information Series No. 317.

    ERIC Educational Resources Information Center

    Crites, John O.

    Evaluating the effectiveness of career guidance programs is a complex process, and few comprehensive models for evaluating such programs exist. Evaluation of career guidance programs has been hampered by the myth that program outcomes are uniform and monolithic. Findings from studies of attribute treatment interactions have revealed only a few…

  20. Challenges to Evaluating Physical Activity Programs in American Indian/Alaska Native Communities

    ERIC Educational Resources Information Center

    Roberts, Erica Blue; Butler, James; Green, Kerry M.

    2018-01-01

    Despite the importance of evaluation to successful programming, a lack of physical activity program (PAP) evaluation for American Indian/Alaska Native (AI/AN) programs exists, which is significant given the high rates of obesity and diabetes in this population. While evaluation barriers have been identified broadly among AI/AN programs, challenges…

  1. Evaluating Evaluations: The Case of Parent Involvement Programs

    ERIC Educational Resources Information Center

    Mattingly, Doreen J.; Prislin, Radmila; McKenzie, Thomas L.; Rodriguez, James L.; Kayzar, Brenda

    2002-01-01

    This article analyzes 41 studies that evaluated K-12 parent involvement programs in order to assess claims that such programs are an effective means of improving student learning. It examines the characteristics of the parent involvement programs, as well as the research design, data, and analytical techniques used in program evaluation. Our…

  2. Development of a program logic model and evaluation plan for a participatory ergonomics intervention in construction.

    PubMed

    Jaegers, Lisa; Dale, Ann Marie; Weaver, Nancy; Buchholz, Bryan; Welch, Laura; Evanoff, Bradley

    2014-03-01

    Intervention studies in participatory ergonomics (PE) are often difficult to interpret due to limited descriptions of program planning and evaluation. In an ongoing PE program with floor layers, we developed a logic model to describe our program plan, and process and summative evaluations designed to describe the efficacy of the program. The logic model was a useful tool for describing the program elements and subsequent modifications. The process evaluation measured how well the program was delivered as intended, and revealed the need for program modifications. The summative evaluation provided early measures of the efficacy of the program as delivered. Inadequate information on program delivery may lead to erroneous conclusions about intervention efficacy due to Type III error. A logic model guided the delivery and evaluation of our intervention and provides useful information to aid interpretation of results. © 2013 Wiley Periodicals, Inc.

  3. Development of a Program Logic Model and Evaluation Plan for a Participatory Ergonomics Intervention in Construction

    PubMed Central

    Jaegers, Lisa; Dale, Ann Marie; Weaver, Nancy; Buchholz, Bryan; Welch, Laura; Evanoff, Bradley

    2013-01-01

    Background Intervention studies in participatory ergonomics (PE) are often difficult to interpret due to limited descriptions of program planning and evaluation. Methods In an ongoing PE program with floor layers, we developed a logic model to describe our program plan, and process and summative evaluations designed to describe the efficacy of the program. Results The logic model was a useful tool for describing the program elements and subsequent modifications. The process evaluation measured how well the program was delivered as intended, and revealed the need for program modifications. The summative evaluation provided early measures of the efficacy of the program as delivered. Conclusions Inadequate information on program delivery may lead to erroneous conclusions about intervention efficacy due to Type III error. A logic model guided the delivery and evaluation of our intervention and provides useful information to aid interpretation of results. PMID:24006097

  4. An Evaluation Program for the Eckerd Foundation Therapeutic Wilderness Camping Program: An Evaluation of an Atypical Alternative Education Program.

    ERIC Educational Resources Information Center

    Griffin, William H.; Carter, James D.

    The strategy used in evaluating an out-of-doors resident camping program for emotionally disturbed children is outlined. This strategy calls for examining the following elements in the program: (1) program goals and objectives; (2) collection and processing program data; (3) camper progress assessment; (4) program audit; (5) assessment of past…

  5. Evaluation Planning, Evaluation Management, and Utilization of Evaluation Results within Adult Literacy Campaigns, Programs and Projects (with Implications for Adult Basic Education and Nonformal Education Programs in General). A Working Paper.

    ERIC Educational Resources Information Center

    Bhola, H. S.

    Addressed to professionals involved in program evaluation, this working paper covers various aspects of evaluation planning, including the following: planning as a sociotechnical process, steps in evaluation planning, program planning and implementation versus evaluation planning and implementation, the literacy system and its subsystems, and some…

  6. Planning Evaluation through the Program Life Cycle

    ERIC Educational Resources Information Center

    Scheirer, Mary Ann; Mark, Melvin M.; Brooks, Ariana; Grob, George F.; Chapel, Thomas J.; Geisz, Mary; McKaughan, Molly; Leviton, Laura

    2012-01-01

    Linking evaluation methods to the several phases of a program's life cycle can provide evaluation planners and funders with guidance about what types of evaluation are most appropriate over the trajectory of social and educational programs and other interventions. If methods are matched to the needs of program phases, evaluation can and should…

  7. The Evaluator's Role in Recommending Program Closure: A Model for Decision Making and Professional Responsibility

    ERIC Educational Resources Information Center

    Eddy, Rebecca M.; Berry, Tiffany

    2009-01-01

    Evaluators face challenges when programs consistently fail to meet expectations for performance or improvement and consequently, evaluators may recommend that closing a program is the most prudent course of action. However, the evaluation literature provides little guidance regarding when an evaluator might recommend program closure. Given…

  8. Evaluation of programs to improve complementary feeding in infants and young children.

    PubMed

    Frongillo, Edward A

    2017-10-01

    Evaluation of complementary feeding programs is needed to enhance knowledge on what works, to document responsible use of resources, and for advocacy. Evaluation is done during program conceptualization and design, implementation, and determination of effectiveness. This paper explains the role of evaluation in the advancement of complementary feeding programs, presenting concepts and methods and illustrating them through examples. Planning and investments for evaluations should occur from the beginning of the project life cycle. Essential to evaluation is articulation of a program theory on how change would occur and what program actions are required for change. Analysis of program impact pathways makes explicit the dynamic connections in the program theory and accounts for contextual factors that could influence program effectiveness. Evaluating implementation functioning is done through addressing questions about needs, coverage, provision, and utilization using information obtained from process evaluation, operations research, and monitoring. Evaluating effectiveness is done through assessing impact, efficiency, coverage, process, and causality. Plausibility designs ask whether the program seemed to have an effect above and beyond external influences, often using a nonrandomized control group and baseline and end line measures. Probability designs ask whether there was an effect using a randomized control group. Evaluations may not be able to use randomization, particularly for programs implemented at a large scale. Plausibility designs, innovative designs, or innovative combinations of designs sometimes are best able to provide useful information. Further work is needed to develop practical designs for evaluation of large-scale country programs on complementary feeding. © 2017 John Wiley & Sons Ltd.

  9. Using Evaluation to Guide and Validate Improvements to the Utah Master Naturalist Program

    ERIC Educational Resources Information Center

    Larese-Casanova, Mark

    2015-01-01

    Integrating evaluation into an Extension program offers multiple opportunities to understand program success through achieving program goals and objectives, delivering programming using the most effective techniques, and refining program audiences. It is less common that evaluation is used to guide and validate the effectiveness of program…

  10. Program Fair Evaluation--Summative Appraisal of Instructional Sequences with Dissimilar Objectives.

    ERIC Educational Resources Information Center

    Popham, W. James

    A comparative evaluation involving two instructional programs is given, although the approach can easily serve to compare more than two programs. The steps involved in conducting a program fair evaluation of two instructional programs are: (1) Identify objectives (a) common to both programs, (b) unique to one program, and (c) unique to the other…

  11. Critical evaluation of international health programs: Reframing global health and evaluation.

    PubMed

    Chi, Chunhuei; Tuepker, Anaïs; Schoon, Rebecca; Núñez Mondaca, Alicia

    2018-04-01

    Striking changes in the funding and implementation of international health programs in recent decades have stimulated debate about the role of communities in deciding which health programs to implement. An important yet neglected piece of that discussion is the need to change norms in program evaluation so that analysis of community ownership, beyond various degrees of "participation," is seen as central to strong evaluation practices. This article challenges mainstream evaluation practices and proposes a framework of Critical Evaluation with 3 levels: upstream evaluation assessing the "who" and "how" of programming decisions; midstream evaluation focusing on the "who" and "how" of selecting program objectives; and downstream evaluation, the focus of current mainstream evaluation, which assesses whether the program achieved its stated objectives. A vital tenet of our framework is that a community possesses the right to determine the path of its health development. A prerequisite of success, regardless of technical outcomes, is that programs must address communities' high priority concerns. Current participatory methods still seldom practice community ownership of program selection because they are vulnerable to funding agencies' predetermined priorities. In addition to critiquing evaluation practices and proposing an alternative framework, we acknowledge likely challenges and propose directions for future research. Copyright © 2018 John Wiley & Sons, Ltd.

  12. A systematic review of evaluated suicide prevention programs targeting indigenous youth.

    PubMed

    Harlow, Alyssa F; Bohanna, India; Clough, Alan

    2014-01-01

    Indigenous young people have significantly higher suicide rates than their non-indigenous counterparts. There is a need for culturally appropriate and effective suicide prevention programs for this demographic. This review assesses suicide prevention programs that have been evaluated for indigenous youth in Australia, Canada, New Zealand, and the United States. The databases MEDLINE and PsycINFO were searched for publications on suicide prevention programs targeting indigenous youth that include reports on evaluations and outcomes. Program content, indigenous involvement, evaluation design, program implementation, and outcomes were assessed for each article. The search yielded 229 articles; 90 abstracts were assessed, and 11 articles describing nine programs were reviewed. Two Australian programs and seven American programs were included. Programs were culturally tailored, flexible, and incorporated multiple-levels of prevention. No randomized controlled trials were found, and many programs employed ad hoc evaluations, poor program description, and no process evaluation. Despite culturally appropriate content, the results of the review indicate that more controlled study designs using planned evaluations and valid outcome measures are needed in research on indigenous youth suicide prevention. Such changes may positively influence the future of research on indigenous youth suicide prevention as the outcomes and efficacy will be more reliable.

  13. Let's get technical: Enhancing program evaluation through the use and integration of internet and mobile technologies.

    PubMed

    Materia, Frank T; Miller, Elizabeth A; Runion, Megan C; Chesnut, Ryan P; Irvin, Jamie B; Richardson, Cameron B; Perkins, Daniel F

    2016-06-01

    Program evaluation has become increasingly important, and information on program performance often drives funding decisions. Technology use and integration can help ease the burdens associated with program evaluation by reducing the resources needed (e.g., time, money, staff) and increasing evaluation efficiency. This paper reviews how program evaluators, across disciplines, can apply internet and mobile technologies to key aspects of program evaluation, which consist of participant registration, participant tracking and retention, process evaluation (e.g., fidelity, assignment completion), and outcome evaluation (e.g., behavior change, knowledge gain). In addition, the paper focuses on the ease of use, relative cost, and fit with populations. An examination on how these tools can be integrated to enhance data collection and program evaluation is discussed. Important limitations of and considerations for technology integration, including the level of technical skill, cost needed to integrate various technologies, data management strategies, and ethical considerations, are highlighted. Lastly, a case study of technology use in an evaluation conducted by the Clearinghouse for Military Family Readiness at Penn State is presented and illustrates how technology integration can enhance program evaluation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Evaluation of Environmental Education in Schools.

    ERIC Educational Resources Information Center

    Connect, 1984

    1984-01-01

    This newsletter discusses the evaluation of environmental education (EE) in schools, highlighting an introductory chapter of a proposed Unesco-United Nations environmental program guide on evaluating such programs. The benefits of evaluating an EE program (including program improvement, growth in student learning, better environment, and program…

  15. Development, implementation, and evaluation of a multi-addiction prevention program for primary school students in Hong Kong: the B.E.S.T. Teen Program.

    PubMed

    Shek, Daniel T L; Yu, Lu; Leung, Hildie; Wu, Florence K Y; Law, Moon Y M

    Based on the evaluation findings of the B.E.S.T. Teen Program which aimed at promoting behavioral, emotional, social, and thinking competencies in primary school students, it is argued in this paper that promotion of psychosocial competence to prevent addiction in primary school students is a promising strategy. A total of 382 Primary 5 (Grade 5) and 297 Primary 6 (Grade 6) students from five primary schools in Hong Kong participated in the program. Different evaluation strategies were adopted to evaluate the program. First, objective outcome evaluation adopting a non-equivalent group pretest-posttest experimental-control group design was conducted to examine change in the students. Second, to gauge students' perceptions of the program, subjective outcome evaluation was conducted. The evaluation findings basically converged to tentatively suggest that young adolescents benefited from participating in the program. Implications on the development, implementation, and evaluation of addiction prevention programs for teenagers are discussed.

  16. Evaluating Faculty Development and Clinical Training Programs in Substance Abuse: A Guide Book.

    ERIC Educational Resources Information Center

    Klitzner, Michael; Stewart, Kathryn

    Intended to provide an overview of program evaluation as it applies to the evaluation of faculty development and clinical training programs in substance abuse for health and mental health professional schools, this guide enables program developers and other faculty to work as partners with evaluators in the development of evaluation designs that…

  17. The Discrepancy Evaluation Model: A Systematic Approach for the Evaluation of Career Planning and Placement Programs.

    ERIC Educational Resources Information Center

    Buttram, Joan L.; Covert, Robert W.

    The Discrepancy Evaluation Model (DEM), developed in 1966 by Malcolm Provus, provides information for program assessment and program improvement. Under the DEM, evaluation is defined as the comparison of an actual performance to a desired standard. The DEM embodies five stages of evaluation based upon a program's natural development: program…

  18. Learning From Small-Scale Experimental Evaluations of After School Programs. Snapshot Number 8

    ERIC Educational Resources Information Center

    Harvard Family Research Project, Harvard University, 2006

    2006-01-01

    The Harvard Family Research Project (HFRP) Out-of-School Time Program Evaluation Database contains profiles of out-of-school time (OST) program evaluations. Its purpose is to provide accessible information about previous and current evaluations to support the development of high quality evaluations and programs in the OST field. Types of Programs…

  19. Evaluation of NASA space grant consortia programs

    NASA Technical Reports Server (NTRS)

    Eisenberg, Martin A.

    1990-01-01

    The meaningful evaluation of the NASA Space Grant Consortium and Fellowship Programs must overcome unusual difficulties: (1) the program, in its infancy, is undergoing dynamic change; (2) the several state consortia and universities have widely divergent parochial goals that defy a uniform evaluative process; and (3) the pilot-sized consortium programs require that the evaluative process be economical in human costs less the process of evaluation comprise the effectiveness of the programs they are meant to assess. This paper represents an attempt to assess the context in which evaluation is to be conducted, the goals and limitations inherent to the evaluation, and to recommend appropriate guidelines for evaluation.

  20. Comet Impacts as a Source of Methane on Titan

    NASA Astrophysics Data System (ADS)

    Howard, Michael; Goldman, N.; Vitello, P. A.

    2006-12-01

    We model comet impacts on Titan as a possible source of atmospheric methane. That is, we study the formation of methane in comet impacts using chemical equilibrium calculations coupled with arbitrary Lagrange-Eulerian (ALE) hydrodynamics. That is, we study the chemical transformation of comet material under high pressure and temperature conditions as it impacts Titan. We assume that the comet is composed of ice, graphite, nitrogen and some hydrocarbons. For certain pressure and temperature regimes, in chemical equilibrium, a significant amount of ice and graphite can be transformed into methane. As a result, we find that a significant amount of methane can be formed in comet collisions on Titan. The methane is formed in the post-impact vapor clouds that form as the comet material expands and cools. We use molecular dynamics to construct an equation of state for the ice surface structures and the comet material. We also study kinetic processes for methane formation during the expansion and cooling phase. We discuss the implication of our results for comets as a possible source of abiotic methane on Titan and its implications on the origin of life. We also discuss the various uncertainties in our model. * This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.

  1. Original Size of the Sudbury Structure: Evidence from Field Investigations and Imaging Radar

    NASA Technical Reports Server (NTRS)

    Lowmman, Paul D., Jr.

    1999-01-01

    This paper summarizes results of continuing studies of the original size of the Sudbury impact structure, including imaging radar and field investigations of supposed "Sudbury breccia" north of the Sudbury Igneous Comples (SIC). Imaging radar acquired from Canada Centre for Remote Sensing (CCRS) aircraft, European Space Agency Remote Sensing Satellite (ERS-1), and RADARSAT shows no evidence of outer rings concentric with the North Range. Illumination directions are such that these rings, presumably extension fractures, would be conspicuous by look azimuth highlighting if they existed. Field mapping supports this interpretation, showing that supposed ring fractures occupied by Huronian sediments are essentially synclines older than the 1850 Ma impact and are not related to the impact. Field investigations of "Sudbury breccia" north of the SIC shows that most if not all of it is inside or along contacts with diabase dykes of the Sudbury Swarm (ca. 1238 Ma), and hence is far too young to be related to the impact. A recently-discovered occurrence of "Sudbury breccia" south of the SIC, near Creighton, is similarly associated with a NW-trending diabase dyke cutting the SIC, supporting the post-impact age of the breccia. It is concluded that the original north rim of the Sudbury crater was not more than 5 to 10 km north of the present North Range SIC contact, and that published estimates of the crater size (ca 200 km diameter) are incorrect.

  2. Impact ejecta and carbonate sequence in the eastern sector of the Chicxulub crater

    NASA Astrophysics Data System (ADS)

    Urrutia-Fucugauchi, Jaime; Chavez-Aguirre, Jose Maria; Pérez-Cruz, Ligia; De la Rosa, Jose Luis

    2008-12-01

    The Chicxulub 200 km diameter crater located in the Yucatan platform of the Gulf of Mexico formed 65 Myr ago and has since been covered by Tertiary post-impact carbonates. The sediment cover and absence of significant volcanic and tectonic activity in the carbonate platform have protected the crater from erosion and deformation, making Chicxulub the only large multi-ring crater in which ejecta is well preserved. Ejecta deposits have been studied by drilling/coring in the southern crater sector and at outcrops in Belize, Quintana Roo and Campeche; little information is available from other sectors. Here, we report on the drilling/coring of a section of ˜34 m of carbonate breccias at 250 m depth in the Valladolid area (120 km away from crater center), which are interpreted as Chicxulub proximal ejecta deposits. The Valladolid breccias correlate with the carbonate breccias cored in the Peto and Tekax boreholes to the south and at similar radial distance. This constitutes the first report of breccias in the eastern sector close to the crater rim. Thickness of the Valladolid breccias is less than that at the other sites, which may indicate erosion of the ejecta deposits before reestablishment of carbonate deposition. The region east of the crater rim appears different from regions to the south and west, characterized by high density and scattered distribution of sinkholes.

  3. Hyperspectral mapping of alteration assemblages within a hydrothermal vug at the Haughton impact structure, Canada

    NASA Astrophysics Data System (ADS)

    Greenberger, Rebecca N.; Mustard, John F.; Osinski, Gordon R.; Tornabene, Livio L.; Pontefract, Alexandra J.; Marion, Cassandra L.; Flemming, Roberta L.; Wilson, Janette H.; Cloutis, Edward A.

    2016-12-01

    Meteorite impacts on Earth and Mars can generate hydrothermal systems that alter the primary mineralogies of rocks and provide suitable environments for microbial colonization. We investigate a calcite-marcasite-bearing vug at the 23 km diameter Haughton impact structure, Devon Island, Nunavut, Canada, using imaging spectroscopy of the outcrop in the field (0.65-1.1 μm) and samples in the laboratory (0.4-2.5 μm), point spectroscopy (0.35-2.5 μm), major element chemistry, and X-ray diffraction analyses. The mineral assemblages mapped at the outcrop include marcasite; marcasite with minor gypsum and jarosite; fibroferrite and copiapite with minor gypsum and melanterite; gypsum, Fe3+ oxides, and jarosite; and calcite, gypsum, clay, microcline, and quartz. Hyperspectral mapping of alteration phases shows spatial patterns that illuminate changes in alteration conditions and formation of specific mineral phases. Marcasite formed from the postimpact hydrothermal system under reducing conditions, while subsequent weathering oxidized the marcasite at low temperatures and water/rock ratios. The acidic fluids resulting from the oxidation collected on flat-lying portions of the outcrop, precipitating fibroferrite + copiapite. That assemblage then likely dissolved, and the changing chemistry and pH resulting from interaction with the calcite-rich host rock formed gypsum-bearing red coatings. These results have implications for understanding water-rock interactions and habitabilities at this site and on Mars.

  4. Association of anatase (TiO2) and microbes: unusual fossilization effect or a potential biosignature?

    USGS Publications Warehouse

    Glamoclija, Mihaela; Andrew Steele,; Marc Fries,; Juergen Schieber,; Voytek, Mary A.; Charles S. Cockell,

    2015-01-01

    We combined microbial paleontology and molecular biology methods to study the Eyreville B drill core from the 35.3-Ma-old Chesapeake Bay impact structure,Virginia, USA. The investigated sample is a pyrite vein collected from the 1353.81-1353.89 m depth interval, located within a section of biotite granite. The granite is a pre-impact rock that was disrupted by the impact event. A search for inorganic (mineral) biosignatures revealed the presence of micron-size rod morphologies of anatase (TiO2) embedded in chlorite coatings on pyrite grains. Neither the Acridine Orange microbial probe nor deoxyribonucleic acid (DNA) extraction followed by polymerase chain reaction (PCR) amplifi cation showed the presence of DNA or ribonucleic acid (RNA) at the location of anatase rods, implying the absence of viable cells in the investigated area. A Nile Red microbial probe revealed the presence of lipids in the rods. Because most of the lipids are resistant over geologic time spans, they are good biomarkers, and they are an indicator of biogenicity for these possibly 35-Ma-old microbial fossils. The mineral assemblage suggests that rod morphologies are associated with low-temperature (<100 °C) hydrothermal alteration that involved aqueous fl uids. The temporal constraints on the anatase fossils are still uncertain because pre-impact alteration of the granite and postimpact heating may have provided identical conditions for anatase precipitation and microbial preservation.

  5. Estimation of hydraulic permeability considering the micro morphology of rocks of the borehole YAXCOPOIL-1 (Impact crater Chicxulub, Mexico)

    NASA Astrophysics Data System (ADS)

    Mayr, S. I.; Burkhardt, H.; Popov, Yu.; Wittmann, A.

    2008-04-01

    Internal surface, formation factor, Nuclear Magnetic Resonance (NMR)-T2 relaxation times and pore radius distributions were measured on representative core samples for the estimation of hydraulic permeability. Permeability is estimated using various versions of the classic Kozeny-Carman-equation (K-C) and a further development of K-C, the fractal PaRiS-model, taking into account the internal surface. In addition to grain and pore size distribution, directly connected to permeability, internal surface reflects the internal structure (“micro morphology”). Lithologies could be grouped with respect to differences in internal surface. Most melt rich impact breccia lithologies exhibit large internal surfaces, while Tertiary post-impact sediments and Cretaceous lithologies in displaced megablocks display smaller internal surfaces. Investigations with scanning electron microscopy confirm the correlation between internal surface and micro morphology. In addition to different versions of K-C, estimations by means of NMR, pore radius distributions and some gas permeability measurements serve for cross-checking and calibration. In general, the different estimations from the independent methods and the measurements are in satisfactory accordance. For Tertiary limestones and Suevites bulk with very high porosities (up to 35%) permeabilites between 10-14 and 10-16 m2 are found, whereas in lower Suevite, Cretaceous anhydrites and dolomites, bulk permeabilites are between 10-15 and 10-23 m2.

  6. Condition of larval red snapper (Lutjanus campechanus) relative to environmental variability and the Deepwater Horizon oil spill

    NASA Astrophysics Data System (ADS)

    Hernandez, F. J., Jr.; Filbrun, J. E.; Fang, J.; Ransom, J. T.

    2016-09-01

    The Deepwater Horizon oil spill (DWHOS) spatially and temporally overlapped with the spawning of many fish species, including Red Snapper, one of the most economically important reef fish in the Gulf of Mexico. To investigate potential impacts of the DWHOS on larval Red Snapper, data from a long-term ichthyoplankton survey off the coast of Alabama were used to examine: (1) larval abundances among pre-impact (2007-2009), impact (2010), and post-impact (2011, 2013) periods; (2) proxies for larval condition (size-adjusted morphometric relationships and dry weight) among the same periods; and (3) the effects of background environmental variation on larval condition. We found that larval Red Snapper were in poorer body condition during 2010, 2011, and 2013 as compared to the 2007-2009 period, a trend that was strongly (and negatively) related to variation in Mobile Bay freshwater discharge. However, larvae collected during and after 2010 were in relatively poor condition even after accounting for variation in freshwater discharge and other environmental variables. By contrast, no differences in larval abundance were detected during these survey years. Taken together, larval supply did not change relative to the timing of the DWHOS, but larval condition was negatively impacted. Even small changes in condition can affect larval survival, so these trends may have consequences for recruitment of larvae to juvenile and adult life stages.

  7. DebriSat Fragment Characterization System and Processing Status

    NASA Technical Reports Server (NTRS)

    Rivero, M.; Shiotani, B.; M. Carrasquilla; Fitz-Coy, N.; Liou, J. C.; Sorge, M.; Huynh, T.; Opiela, J.; Krisko, P.; Cowardin, H.

    2016-01-01

    The DebriSat project is a continuing effort sponsored by NASA and DoD to update existing break-up models using data obtained from hypervelocity impact tests performed to simulate on-orbit collisions. After the impact tests, a team at the University of Florida has been working to characterize the fragments in terms of their mass, size, shape, color and material content. The focus of the post-impact effort has been the collection of 2 mm and larger fragments resulting from the hypervelocity impact test. To date, in excess of 125K fragments have been recovered which is approximately 40K more than the 85K fragments predicted by the existing models. While the fragment collection activities continue, there has been a transition to the characterization of the recovered fragments. Since the start of the characterization effort, the focus has been on the use of automation to (i) expedite the fragment characterization process and (ii) minimize the effects of human subjectivity on the results; e.g., automated data entry processes were developed and implemented to minimize errors during transcription of the measurement data. At all steps of the process, however, there is human oversight to ensure the integrity of the data. Additionally, repeatability and reproducibility tests have been developed and implemented to ensure that the instrumentations used in the characterization process are accurate and properly calibrated.

  8. Gravity investigations of the Chesapeake Bay impact structure

    USGS Publications Warehouse

    Plescia, J.B.; Daniels, D.L.; Shah, A.K.

    2009-01-01

    The Chesapeake Bay impact structure is a complex impact crater, ??85 km in diameter, buried beneath postimpact sediments. Its main structural elements include a central uplift of crystalline bedrock, a surrounding inner crater filled with impact debris, and an annular faulted margin composed of block-faulted sediments. The gravity anomaly is consistent with that of a complex impact consisting of a central positive anomaly over the central uplift and an annular negative anomaly over the inner crater. An anomaly is not recognized as being associated with the faulted margin or the outer edge of the structure. Densities from the Eyreville drill core and modeling indicate a density contrast of ??0.3-0.6 g cm-3 between crystalline basement and the material that fills the inner crater (e.g., Exmore breccia and suevite). This density contrast is somewhat higher than for other impact structures, but it is a function of the manner in which the crater fill was deposited (as a marine resurge deposit). Modeling of the gravity data is consistent with a depth to basement of ??1600 m at the site of Eyreville drill hole and 800 m at the central uplift. Both depths are greater than the depth at which crystalline rocks were encountered in the cores, suggesting that the cored material is highly fractured para-allochthonous rock. ?? 2009 The Geological Society of America.

  9. Noachian and more recent phyllosilicates in impact craters on Mars

    PubMed Central

    Fairén, Alberto G.; Chevrier, Vincent; Abramov, Oleg; Marzo, Giuseppe A.; Gavin, Patricia; Davila, Alfonso F.; Tornabene, Livio L.; Bishop, Janice L.; Roush, Ted L.; Gross, Christoph; Kneissl, Thomas; Uceda, Esther R.; Dohm, James M.; Schulze-Makuch, Dirk; Rodríguez, J. Alexis P.; Amils, Ricardo; McKay, Christopher P.

    2010-01-01

    Hundreds of impact craters on Mars contain diverse phyllosilicates, interpreted as excavation products of preexisting subsurface deposits following impact and crater formation. This has been used to argue that the conditions conducive to phyllosilicate synthesis, which require the presence of abundant and long-lasting liquid water, were only met early in the history of the planet, during the Noachian period (> 3.6 Gy ago), and that aqueous environments were widespread then. Here we test this hypothesis by examining the excavation process of hydrated minerals by impact events on Mars and analyzing the stability of phyllosilicates against the impact-induced thermal shock. To do so, we first compare the infrared spectra of thermally altered phyllosilicates with those of hydrated minerals known to occur in craters on Mars and then analyze the postshock temperatures reached during impact crater excavation. Our results show that phyllosilicates can resist the postshock temperatures almost everywhere in the crater, except under particular conditions in a central area in and near the point of impact. We conclude that most phyllosilicates detected inside impact craters on Mars are consistent with excavated preexisting sediments, supporting the hypothesis of a primeval and long-lasting global aqueous environment. When our analyses are applied to specific impact craters on Mars, we are able to identify both pre- and postimpact phyllosilicates, therefore extending the time of local phyllosilicate synthesis to post-Noachian times. PMID:20616087

  10. Noachian and more recent phyllosilicates in impact craters on Mars.

    PubMed

    Fairén, Alberto G; Chevrier, Vincent; Abramov, Oleg; Marzo, Giuseppe A; Gavin, Patricia; Davila, Alfonso F; Tornabene, Livio L; Bishop, Janice L; Roush, Ted L; Gross, Christoph; Kneissl, Thomas; Uceda, Esther R; Dohm, James M; Schulze-Makuch, Dirk; Rodríguez, J Alexis P; Amils, Ricardo; McKay, Christopher P

    2010-07-06

    Hundreds of impact craters on Mars contain diverse phyllosilicates, interpreted as excavation products of preexisting subsurface deposits following impact and crater formation. This has been used to argue that the conditions conducive to phyllosilicate synthesis, which require the presence of abundant and long-lasting liquid water, were only met early in the history of the planet, during the Noachian period (> 3.6 Gy ago), and that aqueous environments were widespread then. Here we test this hypothesis by examining the excavation process of hydrated minerals by impact events on Mars and analyzing the stability of phyllosilicates against the impact-induced thermal shock. To do so, we first compare the infrared spectra of thermally altered phyllosilicates with those of hydrated minerals known to occur in craters on Mars and then analyze the postshock temperatures reached during impact crater excavation. Our results show that phyllosilicates can resist the postshock temperatures almost everywhere in the crater, except under particular conditions in a central area in and near the point of impact. We conclude that most phyllosilicates detected inside impact craters on Mars are consistent with excavated preexisting sediments, supporting the hypothesis of a primeval and long-lasting global aqueous environment. When our analyses are applied to specific impact craters on Mars, we are able to identify both pre- and postimpact phyllosilicates, therefore extending the time of local phyllosilicate synthesis to post-Noachian times.

  11. Indirect ignition of energetic materials with laser-driven flyer plates.

    PubMed

    Dean, Steven W; De Lucia, Frank C; Gottfried, Jennifer L

    2017-01-20

    The impact of laser-driven flyer plates on energetic materials CL-20, PETN, and TATB has been investigated. Flyer plates composed of 25 μm thick Al were impacted into the energetic materials at velocities up to 1.3 km/s. The flyer plates were accelerated by means of an Nd:YAG laser pulse. The laser pulse generates rapidly expanding plasma between the flyer plate foil and the substrate to which it is adhered. As the plasma grows, a section of the metal foil is ejected at high speed, forming the flyer plate. The velocity of the flyer plate was determined using VISAR, time of flight, and high-speed video. The response of the energetic material to impact was determined by light emission recorded by an infrared-sensitive photodiode. Following post-impact analysis of the impacted energetic material, it was hypothesized that the light emitted by the material after impact is not due to the impact of the flyer itself but rather is caused by the decomposition of energetic material ejected (via the shock of flyer plate impact) into a cloud of hot products generated during the launch of the flyer plate. This hypothesis was confirmed through schlieren imaging of a flyer plate launch, clearly showing the ejection of hot gases and particles from the region surrounding the flyer plate launch and the burning of the ejected energetic material particles.

  12. Right timing in formative program evaluation.

    PubMed

    Hall, Jori; Freeman, Melissa; Roulston, Kathy

    2014-08-01

    Since many educational researchers and program developers have limited knowledge of formative evaluation, formative data may be underutilized during the development and implementation of an educational program. The purpose of this article is to explain how participatory, responsive, educative, and qualitative approaches to formative evaluation can facilitate a partnership between evaluators and educational researchers and program managers to generate data useful to inform program implementation and improvement. This partnership is critical, we argue, because it enables an awareness of when to take appropriate action to ensure successful educational programs or "kairos". To illustrate, we use examples from our own evaluation work to highlight how formative evaluation may facilitate opportune moments to (1) define the substance and purpose of a program, (2) develop understanding and awareness of the cultural interpretations of program participants, and (3) show the relevance of stakeholder experiences to program goals. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Moving the Needle on Program Quality: An Examination of the Organizational Characteristics That Drive Improvement in Expanded Learning Programs

    ERIC Educational Resources Information Center

    McCormick, Silvana

    2017-01-01

    Program evaluation can play a critical role in supporting high quality implementation of social programs to help them achieve their goal of social impact. Evaluation scholars have developed a wide range of strategies to help build programs' internal evaluation capacity in an effort to support meaningful use of evaluation. However, the evaluation…

  14. FHWA Research and Technology Evaluation: Public-Private Partnership Capacity Building Program

    DOT National Transportation Integrated Search

    2018-02-01

    This report details the evaluation of the Federal Highway Administrations Office of Innovative Program Delivery Public-Private Partnership (P3) Capacity Building Program (P3 Program). The evaluators focused on the P3 Programs P3 Toolkit as an e...

  15. The Value in Evaluating and Communicating Program Impact: The Ohio BR&E Program

    ERIC Educational Resources Information Center

    Daivs, Gregory

    2012-01-01

    Assessing program impact can provide useful program evaluation data. It also provides a basis for program development, marketing, and justification. This article discusses recent impact evaluation efforts and findings of a long-time Extension program; referred to as Business Retention and Expansion (BR&E). How such information can be…

  16. 76 FR 62813 - Pilot Program To Evaluate Proposed Proprietary Name Submissions; Public Meeting on Pilot Program...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ...] Pilot Program To Evaluate Proposed Proprietary Name Submissions; Public Meeting on Pilot Program Results... voluntary pilot program that enabled participating pharmaceutical firms to evaluate proposed proprietary... public meeting at the end of fiscal year 2011 to discuss the results of the pilot program, but the Agency...

  17. General Criteria for Evaluating Social Programs.

    ERIC Educational Resources Information Center

    Shipman, Stephanie

    1989-01-01

    A framework of general evaluation criteria for ensuring the comprehensiveness of program reviews and appropriate and fair comparison of children's programs is outlined. It has two components: (1) descriptive; and (2) evaluative. The framework was developed by researchers at the General Accounting Office for evaluation of federal programs. (TJH)

  18. 29 CFR 1960.80 - Secretary's evaluations of agency occupational safety and health programs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... EMPLOYEE OCCUPATIONAL SAFETY AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs § 1960.80 Secretary's evaluations of agency occupational safety and health... evaluating an agency's occupational safety and health program. To accomplish this, the Secretary shall...

  19. 29 CFR 1960.80 - Secretary's evaluations of agency occupational safety and health programs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... EMPLOYEE OCCUPATIONAL SAFETY AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs § 1960.80 Secretary's evaluations of agency occupational safety and health... evaluating an agency's occupational safety and health program. To accomplish this, the Secretary shall...

  20. 29 CFR 1960.80 - Secretary's evaluations of agency occupational safety and health programs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... EMPLOYEE OCCUPATIONAL SAFETY AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs § 1960.80 Secretary's evaluations of agency occupational safety and health... evaluating an agency's occupational safety and health program. To accomplish this, the Secretary shall...

  1. 29 CFR 1960.80 - Secretary's evaluations of agency occupational safety and health programs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... EMPLOYEE OCCUPATIONAL SAFETY AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs § 1960.80 Secretary's evaluations of agency occupational safety and health... evaluating an agency's occupational safety and health program. To accomplish this, the Secretary shall...

  2. Program Evaluation Interest and Skills of School Counselors

    ERIC Educational Resources Information Center

    Astramovich, Randall L.

    2017-01-01

    School counselors participated in a study examining their program evaluation interest and skills. Findings suggest that school counselors understand the importance of program evaluation, yet they may lack the skills and confidence to successfully engage in program evaluation activities. Professional development training may be an important method…

  3. 29 CFR 1960.80 - Secretary's evaluations of agency occupational safety and health programs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... EMPLOYEE OCCUPATIONAL SAFETY AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs § 1960.80 Secretary's evaluations of agency occupational safety and health... evaluating an agency's occupational safety and health program. To accomplish this, the Secretary shall...

  4. Evaluating adolescent pregnancy programs: rethinking our priorities.

    PubMed

    Stahler, G J; DuCette, J P

    1991-01-01

    Noting that impact evaluations of adolescent pregnancy programs are characterized by poor quality, the authors recommend using a different standard in assessing the value of programs. While the number of adolescent pregnancy programs has multiplied during the last 3 decades, little is known about their impact in ameliorating the negative consequences of too-early childbearing. An ideal evaluation of these programs would randomly select and randomly assign subjects to experimental and control groups. But evaluations conducted by individual program generally face obstacles that limit the randomness of the study. most individual programs lack the financial resources and do not employ the full-time professional evaluators needed to carry out a valid evaluation. These factors result in too short an evaluation period, incomplete and inaccurate data, and lack of randomness in the assignment of control groups. To more accurately assess the impact of the programs, the authors recommend that individual programs focus on process evaluation and collection of complete and reliable data on their clients. From the onset, a program should have a clear description of its content, logic of intervention, and method of implementation. It should maintain thorough records on client characteristics, service utilization, and should conduct long-term follow-ups. For rigorous impact evaluations, programs should rely on 3rd party entities. These independent organizations -- universities or research institutes -- do not have a stake in the outcome of the evaluation, making the study all the more objective. Furthermore, they provide experienced researchers.

  5. Evaluation readiness: improved evaluation planning using a data inventory framework.

    PubMed

    Cohen, A B; Hall, K C; Cohodes, D R

    1985-01-01

    Factors intrinsic to many programs, such as ambiguously stated objectives, inadequately defined performance measures, and incomplete or unreliable databases, often conspire to limit the evaluability of these programs. Current evaluation planning approaches are somewhat constrained in their ability to overcome these obstacles and to achieve full preparedness for evaluation. In this paper, the concept of evaluation readiness is introduced as a complement to other evaluation planning approaches, most notably that of evaluability assessment. The basic products of evaluation readiness--the formal program definition and the data inventory framework--are described, along with a guide for assuring more timely and appropriate evaluation response capability to support the decision making needs of program managers. The utility of evaluation readiness for program planning, as well as for effective management, is also discussed.

  6. Measuring Success: Evaluating Educational Programs

    ERIC Educational Resources Information Center

    Fisher, Yael

    2010-01-01

    This paper reveals a new evaluation model, which enables educational program and project managers to evaluate their programs with a simple and easy to understand approach. The "index of success model" is comprised of five parameters that enable to focus on and evaluate both the implementation and results of an educational program. The…

  7. The Role of Evaluation and Plans for Evaluating the Current Testing Program.

    ERIC Educational Resources Information Center

    Winters, Lynn

    The Palos Verdes Peninsula Unified School District Office of Program Evaluation and Research is responsible for providing information for program development and improvement; providing test information to special programs coordinators; and acting as a clearinghouse for all information concerning tests, evaluation methodology, and educational…

  8. Tools for Formative Evaluation: Gathering the Information Necessary for Program Improvement

    ERIC Educational Resources Information Center

    Jayaratne, K. S. U.

    2016-01-01

    New Extension educators experience a steep learning curve when attempting to develop effective Extension programs. Formative evaluation is helpful to new, and experienced, Extension educators in determining the changes necessary for making programs more effective. Formative evaluation is an essential part of program evaluation. However, its use…

  9. Dissemination and implementation science in program evaluation: A telemental health clinical consultation case example.

    PubMed

    Arora, Prerna G; Connors, Elizabeth H; Blizzard, Angela; Coble, Kelly; Gloff, Nicole; Pruitt, David

    2017-02-01

    Increased attention has been placed on evaluating the extent to which clinical programs that support the behavioral health needs of youth have effective processes and result in improved patient outcomes. Several theoretical frameworks from dissemination and implementation (D&I) science have been put forth to guide the evaluation of behavioral health program implemented in the context of real-world settings. Although a strong rationale for the integration of D&I science in program evaluation exists, few examples exist available to guide the evaluator in integrating D&I science in the planning and execution of evaluation activities. This paper seeks to inform program evaluation efforts by outlining two D&I frameworks and describing their integration in program evaluation design. Specifically, this paper seeks to support evaluation efforts by illustrating the use of these frameworks via a case example of a telemental health consultation program in pediatric primary care designed to improve access to behavioral health care for children and adolescents in rural settings. Lessons learned from this effort, as well as recommendations regarding the future evaluation of programs using D&I science to support behavioral health care in community-based settings are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. From Implementation to Outcomes to Impacts: Designing a Comprehensive Program Evaluation

    NASA Astrophysics Data System (ADS)

    Shebby, S.

    2015-12-01

    Funders are often interested in learning about the impact of program activities, yet before the impacts are determined, educational evaluations should first examine program implementation and outcomes. Implementation evaluation examines how and the extent to which program activities are delivered as intended, including the extent to which activities reached the targeted participants. Outcome evaluation is comprised of a systematic examination of the effects that a program has on program participants, such as changes in knowledge, attitudes, beliefs, values, and behaviors. In this presentation, presenters will share insights on evaluating the implementation, outcomes, and impacts associated with an online science curriculum for K-2 students. The science curriculum was designed to provide students with access to science concepts and skills in an interactive and innovative environment, and teachers with embedded, aligned, and on-demand professional development. One of the most important—and challenging—steps in this evaluation was to select outcomes that were well-defined, measurable, and aligned to program activities, as well as relevant to program stakeholders. An additional challenge was to measure implementation given limited access to the classroom environment. This presentation will include a discussion of the process evaluators used to select appropriate implementation indicators and outcomes (teacher and student), design an evaluation approach, and craft data collection instruments. Although examples provided are specific to the K-2 science intervention, the best practices discussed are pertinent to all program and event evaluations. Impact evaluation goes beyond implementation and outcome evaluation to inform whether a program is working or not. It requires a comparison group to inform what outcomes would have been in the absence of the intervention. As such, this presentation will also include a discussion of impacts, including how impacts are defined and measured, and some common challenges in evaluating program impact.

  11. Lazy evaluation of FP programs: A data-flow approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wei, Y.H.; Gaudiot, J.L.

    1988-12-31

    This paper presents a lazy evaluation system for the list-based functional language, Backus` FP in data-driven environment. A superset language of FP, called DFP (Demand-driven FP), is introduced. FP eager programs are transformed into DFP lazy programs which contain the notions of demands. The data-driven execution of DFP programs has the same effects of lazy evaluation. DFP lazy programs have the property of always evaluating a sufficient and necessary result. The infinite sequence generator is used to demonstrate the eager-lazy program transformation and the execution of the lazy programs.

  12. Summary of Program Evaluation Results: 1985-1986 School Year Pre-Kindergarten Educational Program.

    ERIC Educational Resources Information Center

    Heath, Robert W.; And Others

    Reported are findings of the 1985-86 program evaluation of the prenatal-to-preschool and preschool programs operating under the auspices of the Kamehameha Schools/Bishop Estate. Evaluation of the prenatal-to-preschool program (the Kupulani Program) included item analysis of the Questions about Pregnancy Test, development of a revised data…

  13. Integrating Program Theory and Systems-Based Procedures in Program Evaluation: A Dynamic Approach to Evaluate Educational Programs

    ERIC Educational Resources Information Center

    Grammatikopoulos, Vasilis

    2012-01-01

    The current study attempts to integrate parts of program theory and systems-based procedures in educational program evaluation. The educational program that was implemented, called the "Early Steps" project, proposed that physical education can contribute to various educational goals apart from the usual motor skills improvement. Basic…

  14. Leisure Today. Leisure Programming: The State of the Art.

    ERIC Educational Resources Information Center

    Busser, James A.; And Others

    1993-01-01

    Nine articles examine current topics in leisure programing, including program design and evaluation, program design through imagery, keys to quality leisure programing, programing with style, total quality program planning, evaluation of leisure programs, programing for older adults, and the intergenerational entrepreneurship demonstration…

  15. Evaluating Educational Programs.

    ERIC Educational Resources Information Center

    Ball, Samuel

    The activities of Educational Testing Service (ETS) in evaluating educational programs are described. Program evaluations are categorized as needs assessment, formative evaluation, or summative evaluation. Three classic efforts which illustrate the range of ETS' participation are the Pennsylvania Goals Study (1965), the Coleman Report--Equality of…

  16. The opportunities and challenges of multi-site evaluations: lessons from the jail diversion and trauma recovery national cross-site evaluation.

    PubMed

    Stainbrook, Kristin; Penney, Darby; Elwyn, Laura

    2015-06-01

    Multi-site evaluations, particularly of federally funded service programs, pose a special set of challenges for program evaluation. Not only are there contextual differences related to project location, there are often relatively few programmatic requirements, which results in variations in program models, target populations and services. The Jail Diversion and Trauma Recovery-Priority to Veterans (JDTR) National Cross-Site Evaluation was tasked with conducting a multi-site evaluation of thirteen grantee programs that varied along multiple domains. This article describes the use of a mixed methods evaluation design to understand the jail diversion programs and client outcomes for veterans with trauma, mental health and/or substance use problems. We discuss the challenges encountered in evaluating diverse programs, the benefits of the evaluation in the face of these challenges, and offer lessons learned for other evaluators undertaking this type of evaluation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. A Bereavement Support Program for Survivors of Cancer Deaths: A Description and Evaluation.

    ERIC Educational Resources Information Center

    Souter, Susan J.; Moore, Timothy E.

    1990-01-01

    Describes bereavement support program for survivors of cancer deaths developed by Riverdale Hospital in Toronto, Ontario. Presents detailed program evaluation which asked bereaved survivors who were program participants for one year to evaluate program aspects and facilitation of their grief by volunteers. Recommendations for expansion and…

  18. Title V Delinquency Prevention Program. Community Self-Evaluation Workbook.

    ERIC Educational Resources Information Center

    Caliber Associates, Fairfax, VA.

    This workbook is designed to help communities and program administrators assess the success of their Title V delinquency prevention programs, but it may serve as an evaluation tool for other prevention efforts as well. It provides information and resource aids on program planning, conducting evaluations, tracking programs, describing activities,…

  19. The Evaluation and Research of Multi-Project Programs: Program Component Analysis.

    ERIC Educational Resources Information Center

    Baker, Eva L.

    1977-01-01

    It is difficult to base evaluations on concepts irrelevant to state policy making. Evaluation of a multiproject program requires both time and differentiation of method. Data from the California Early Childhood Program illustrate process variables for program component analysis, and research questions for intraprogram comparison. (CP)

  20. LEA Title VII Program Evaluations. Panel Presentations.

    ERIC Educational Resources Information Center

    Balu, Raj

    These panel presentations focus on LEA Title VII Program Evaluations. Raj Balu, an administrator of bilingual programs in Chicago presents information regarding the bilingual education program in the Chicago public schools, as well as information on Title VII programs and what kind of evaluation is being done. Jesus Salazar, who is currently…

  1. Evaluating Social Programs at the State and Local Level. The JTPA Evaluation Design Project.

    ERIC Educational Resources Information Center

    Blalock, Ann Bonar, Ed.; And Others

    This book on evaluating social programs is an outcome of the Job Training Partnership Act (JTPA) Evaluation Design Project, which produced a set of 10 guides for the evaluation of state and local JTPA programs. This book distills ideas from these guides and applies them to a larger context. Part 1 presents a general approach to program evaluation…

  2. Mercury as the Unaccreted Projectile: Thermal Consequences

    NASA Astrophysics Data System (ADS)

    Asphaug, Erik; Gabriel, Travis; Jackson, Alan; Perera, Viranga

    2017-10-01

    Mercury retained substantial volatiles during its formation, in far greater proportion than the Moon, despite losing ~2/3 of its rocky mantle. Its volatile-rich geochemistry would contraindicate a giant impact because it would drive away the volatiles, as in the hypothesis for the Moon. However, the thermal consequences of Mercury formation vary considerably between the two giant impact scenarios, ‘direct hit’ (DH; Benz et al. 1989) and ‘hit and run’ (HR; Asphaug and Reufer 2014). Each begins with a differentiated chondritic proto-Mercury (PM) a bit larger than Mars. In DH, PM gets eroded by a very energetic impactor half its mass, at ~6-7 times the escape velocity. To remove half of PM’s mantle, the post-impact target gets completely shock-vaporized and is sheared apart into space. The bound remnant in DH would experience a comparable deposition of shock enthalpy, as in Moon formation, and would expand into a much larger volume of heliocentric space, leading to a dry planet. The bound remnant will go on to re-accrete much of the silicate mantle that it just lost, another challenge for DH. In HR, PM is the projectile that slams into a terrestrial planet twice its size (proto-Venus or proto-Earth). For typical impact angle and speed, a typical outcome is to ‘bounce”. But for HR to explain Mercury, PM must avoid accretion every time it encounters the target, until it is scattered or migrates away (or is accreted, in which case there is no Mercury), leading to multi-HR scenarios. Tides are intense in HR because the projectile grazes the target core; gravity does most of the work of mantle stripping. Shocks play a secondary role. Whereas in DH the impactor blasts the target inside-out, in HR the runner emerges relatively unshocked, and undispersed except for losing the gravitationally-unbound material. HR is a mechanism for collecting low-shocked remnants, because the intensely shocked material ends up bound to the target or escaping to heliocentric space; little of it is accreted by the runner. We compare single-HR and slower multiple-HR scenarios, with DH scenarios, evaluating enthalpy production within the bound remnant in SPH simulations.

  3. Program Theory and Quality Matter: Changing the Course of Extension Program Evaluation

    ERIC Educational Resources Information Center

    Arnold, Mary E.; Cater, Melissa

    2016-01-01

    As internal evaluators for the 4-H program in two states, we simultaneously yet independently began to change the way we approached our evaluation practices, turning from evaluation capacity building (ECB) efforts that prepared educators to define and measure program outcomes to strategies that engage educators in defining and measuring program…

  4. Program Evaluation of Community College Learning Assistance Centers: What Do LAC Directors Think?

    ERIC Educational Resources Information Center

    Franklin, Doug; Blankenberger, Bob

    2016-01-01

    Objective: This study seeks to determine the nature of current program evaluation practices for learning assistance centers (LACs), the practices being used for program evaluation, and whether LAC directors believe their practices are appropriate for evaluating program effectiveness. Method: We conducted a survey (n = 61) of community college LAC…

  5. The Mother and Infant Home Visiting Program Evaluation: Early Findings on the Maternal, Infant, and Early Childhood Home Visiting Program. A Report to Congress. OPRE Report 2015-11

    ERIC Educational Resources Information Center

    Michalopoulos, Charles; Lee, Helen; Duggan, Anne; Lundquist, Erika; Tso, Ada; Crowne, Sarah Shea; Burrell, Lori; Somers, Jennifer; Filene, Jill H.; Knox, Virginia

    2015-01-01

    "The Mother and Infant Home Visiting Program Evaluation: Early Findings on the Maternal, Infant, and Early Childhood Home Visiting Program--A Report to Congress" presents the first findings from the Mother and Infant Home Visiting Program Evaluation (MIHOPE), the legislatively mandated national evaluation of the Maternal, Infant, and…

  6. EVALUE : a computer program for evaluating investments in forest products industries

    Treesearch

    Peter J. Ince; Philip H. Steele

    1980-01-01

    EVALUE, a FORTRAN program, was developed to provide a framework for cash flow analysis of investment opportunities. EVALUE was designed to assist researchers in evaluating investment feasibility of new technology or new manufacturing processes. This report serves as user documentation for the EVALUE program. EVALUE is briefly described and notes on preparation of a...

  7. Using Evaluability Assessment to Improve Program Evaluation for the Blue-Throated Macaw Environmental Education Project in Bolivia

    ERIC Educational Resources Information Center

    Salvatierra da Silva, Daniela; Jacobson, Susan K.; Monroe, Martha C.; Israel, Glenn D.

    2016-01-01

    An evaluability assessment of a program to save a critically endangered bird helped prepare the Blue-throated Macaw Environmental Education Project for evaluation and program improvement. The evaluability assessment facilitated agreement among key stakeholders on evaluation criteria and intended uses of evaluation information in order to maximize…

  8. An evaluation capacity building toolkit for principal investigators of undergraduate research experiences: A demonstration of transforming theory into practice.

    PubMed

    Rorrer, Audrey S

    2016-04-01

    This paper describes the approach and process undertaken to develop evaluation capacity among the leaders of a federally funded undergraduate research program. An evaluation toolkit was developed for Computer and Information Sciences and Engineering(1) Research Experiences for Undergraduates(2) (CISE REU) programs to address the ongoing need for evaluation capacity among principal investigators who manage program evaluation. The toolkit was the result of collaboration within the CISE REU community with the purpose being to provide targeted instructional resources and tools for quality program evaluation. Challenges were to balance the desire for standardized assessment with the responsibility to account for individual program contexts. Toolkit contents included instructional materials about evaluation practice, a standardized applicant management tool, and a modulated outcomes measure. Resulting benefits from toolkit deployment were having cost effective, sustainable evaluation tools, a community evaluation forum, and aggregate measurement of key program outcomes for the national program. Lessons learned included the imperative of understanding the evaluation context, engaging stakeholders, and building stakeholder trust. Results from project measures are presented along with a discussion of guidelines for facilitating evaluation capacity building that will serve a variety of contexts. Copyright © 2016. Published by Elsevier Ltd.

  9. The Software Line-up: What Reviewers Look for When Evaluating Software.

    ERIC Educational Resources Information Center

    ELECTRONIC Learning, 1982

    1982-01-01

    Contains a check list to aid teachers in evaluating software used in computer-assisted instruction on microcomputers. The evaluation form contains three sections: program description, program evaluation, and overall evaluation. A brief description of a software evaluation program in use at the Granite School District in Utah is included. (JJD)

  10. Using Program Theory-Driven Evaluation Science to Crack the Da Vinci Code

    ERIC Educational Resources Information Center

    Donaldson, Stewart I.

    2005-01-01

    Program theory-driven evaluation science uses substantive knowledge, as opposed to method proclivities, to guide program evaluations. It aspires to update, clarify, simplify, and make more accessible the evolving theory of evaluation practice commonly referred to as theory-driven or theory-based evaluation. The evaluator in this chapter provides a…

  11. The Cost-Income Compenent of Program Evaluation.

    ERIC Educational Resources Information Center

    Miner, Norris

    Cost-income studies are designed to serve two functions in instructional program evaluation. First, they act as the indicator of the economic value of a program. This economic value in conjunction with the other educational values needed in program evaluation allow for the most realistic appraisal of program worth. Second, if the studies show a…

  12. Program Theory Evaluation: Logic Analysis

    ERIC Educational Resources Information Center

    Brousselle, Astrid; Champagne, Francois

    2011-01-01

    Program theory evaluation, which has grown in use over the past 10 years, assesses whether a program is designed in such a way that it can achieve its intended outcomes. This article describes a particular type of program theory evaluation--logic analysis--that allows us to test the plausibility of a program's theory using scientific knowledge.…

  13. Better Crunching: Recommendations for Multivariate Data Analysis Approaches for Program Impact Evaluations

    ERIC Educational Resources Information Center

    Braverman, Marc T.

    2016-01-01

    Extension program evaluations often present opportunities to analyze data in multiple ways. This article suggests that program evaluations can involve more sophisticated data analysis approaches than are often used. On the basis of a hypothetical program scenario and corresponding data set, two approaches to testing for evidence of program impact…

  14. Testing of a Program Evaluation Model: Final Report.

    ERIC Educational Resources Information Center

    Nagler, Phyllis J.; Marson, Arthur A.

    A program evaluation model developed by Moraine Park Technical Institute (MPTI) is described in this report. Following background material, the four main evaluation criteria employed in the model are identified as program quality, program relevance to community needs, program impact on MPTI, and the transition and growth of MPTI graduates in the…

  15. The Houston Community College Eligible Legalized Alien Program. Evaluation Program. Evaluation Report.

    ERIC Educational Resources Information Center

    Seaman, Don F.; Cuellar, Sylvia

    The Houston Community College (Texas) program (TOTAL ACCESS) designed in response to the Immigration Reform and Control Act of 1986, is described and evaluated. The program offers classes to eligible aliens (97% Hispanic Americans from Mexico, El Salvador, and Guatemala) wishing to pursue the educational program required for legalization. Program…

  16. Redesigning and aligning assessment and evaluation for a federally funded math and science teacher educational program.

    PubMed

    Hardré, Patricia L; Slater, Janis; Nanny, Mark

    2010-11-01

    This paper examines the redesign of evaluation components for a teacher professional development project funded by the National Science Foundation. It focuses on aligning evaluation instrumentation and strategies with program goals, research goals and program evaluation best practices. The study identifies weaknesses in the original (year 1) program evaluation design and implementation, develops strategies and tracks changes for year 2 implementation, and then reports enhancement of findings and recommendations for year 3. It includes lessons learned about assessment and evaluation over the project lifespan, with implications for research and evaluation of a range of related programs. This study functions as a classic illustration of how critical it is to observe first principles of assessment and evaluation for funded programs, the risks that arise when they are ignored, and the benefits that accrue when they are systematically observed. Copyright (c) 2009. Published by Elsevier Ltd.

  17. Solar energy program evaluation: an introduction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    deLeon, P.

    The Program Evaluation Methodology provides an overview of the practice and methodology of program evaluation and defines more precisely the evaluation techniques and methodologies that would be most appropriate to government organizations which are actively involved in the research, development, and commercialization of solar energy systems. Formal evaluation cannot be treated as a single methodological approach for assessing a program. There are four basic types of evaluation designs - the pre-experimental design; the quasi-experimental design based on time series; the quasi-experimental design based on comparison groups; and the true experimental design. This report is organized to first introduce the rolemore » and issues of evaluation. This is to provide a set of issues to organize the subsequent sections detailing the national solar energy programs. Then, these two themes are integrated by examining the evaluation strategies and methodologies tailored to fit the particular needs of the various individual solar energy programs. (MCW)« less

  18. Iterative Evaluation in a Mobile Counseling and Testing Program to Reach People of Color at Risk for HIV--New Strategies Improve Program Acceptability, Effectiveness, and Evaluation Capabilities

    ERIC Educational Resources Information Center

    Spielberg, Freya; Kurth, Ann; Reidy, William; McKnight, Teka; Dikobe, Wame; Wilson, Charles

    2011-01-01

    This article highlights findings from an evaluation that explored the impact of mobile versus clinic-based testing, rapid versus central-lab based testing, incentives for testing, and the use of a computer counseling program to guide counseling and automate evaluation in a mobile program reaching people of color at risk for HIV. The program's…

  19. State Education Department: Security over Pupil Evaluation Program and Program Evaluation Test Materials Needs Improvement. Report 91-S-2.

    ERIC Educational Resources Information Center

    New York State Office of the Comptroller, Albany.

    Findings of an audit of the New York State Education Department's procedures to maintain security over Pupil Evaluation Program (PEP) and Program Evaluation Test (PET) examination materials are presented in this report. The audit sought to determine whether the department's security procedures adequately prevented unauthorized access to exam…

  20. Austin Independent School District Office of Program Evaluation Agenda 1998-99. Publication Number 98.01.

    ERIC Educational Resources Information Center

    Austin Independent School District, TX. Office of Program Evaluation.

    The Office of Program Evaluation (OPE) of the Austin Independent School District (Texas) (AISD) is charged with evaluating federally, locally, and state funded programs in the AISD. OPE staff carry out mandated reporting for federal and state grants and are increasingly involved in formative evaluations designed for program improvement and…

  1. How To Design a Program Evaluation. CSE Program Evaluation Kit, Volume 3. Second Edition.

    ERIC Educational Resources Information Center

    Fitz-Gibbon, Carol Taylor; Morris, Lynn Lyons

    The "CSE Program Evaluation Kit" is a series of nine books intended to assist people conducting program evaluations. This volume, the third in the kit, discusses the logic underlying the use of quantitative research designs, including the pretest-posttest design, and supplies step-by-step procedures for setting up and interpreting the…

  2. Integrating Data Mining in Program Evaluation of K-12 Online Education

    ERIC Educational Resources Information Center

    Hung, Jui-Long; Hsu, Yu-Chang; Rice, Kerry

    2012-01-01

    This study investigated an innovative approach of program evaluation through analyses of student learning logs, demographic data, and end-of-course evaluation surveys in an online K-12 supplemental program. The results support the development of a program evaluation model for decision making on teaching and learning at the K-12 level. A case study…

  3. 45 CFR 2516.850 - What will the Corporation do to evaluate the overall success of the service-learning program?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... overall success of the service-learning program? 2516.850 Section 2516.850 Public Welfare Regulations...-LEARNING PROGRAMS Evaluation Requirements § 2516.850 What will the Corporation do to evaluate the overall success of the service-learning program? (a) The Corporation will conduct independent evaluations. These...

  4. 45 CFR 2516.850 - What will the Corporation do to evaluate the overall success of the service-learning program?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... overall success of the service-learning program? 2516.850 Section 2516.850 Public Welfare Regulations...-LEARNING PROGRAMS Evaluation Requirements § 2516.850 What will the Corporation do to evaluate the overall success of the service-learning program? (a) The Corporation will conduct independent evaluations. These...

  5. Non-Formal Educator Use of Evaluation Results

    ERIC Educational Resources Information Center

    Baughman, Sarah; Boyd, Heather H.; Franz, Nancy K.

    2012-01-01

    Increasing demands for accountability in educational programming have resulted in increasing calls for program evaluation in educational organizations. Many organizations include conducting program evaluations as part of the job responsibilities of program staff. Cooperative Extension is a complex organization offering non-formal educational…

  6. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM: PROGRESS AND ACCOMPLISHMENTS - FISCAL YEAR 1991

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) program was the first major program for demonstrating and evaluating full-scale innovative treatment technologies at hazardous waste sites. Having concluded its fifth year, the SITE program is recognized as a leading advocate ...

  7. Using Curriculum-Based Measurements for Program Evaluation: Expanding Roles for School Psychologists

    ERIC Educational Resources Information Center

    Tusing, Mary E.; Breikjern, Nicholle A.

    2017-01-01

    Educators increasingly need to evaluate schoolwide reform efforts; however, complex program evaluations often are not feasible in schools. Through a case example, we provide a heuristic for program evaluation that is easily replicated in schools. Criterion-referenced interpretations of schoolwide screening data were used to evaluate outcomes…

  8. Using Evaluation and Research Theory to Improve Programs in Applied Settings: An Interview with Thomas D. Cook.

    ERIC Educational Resources Information Center

    Buescher, Thomas M.

    1986-01-01

    An interview with T. Cook, author of works on the use of research and evaluation theory and design, touches on such topics as practical evaluation, planning programs with evaluation or research design, and evaluation of programs for gifted students. (CL)

  9. Modification and Adaptation of the Program Evaluation Standards in Saudi Arabia

    ERIC Educational Resources Information Center

    Alyami, Mohammed

    2013-01-01

    The Joint Committee on Standards for Educational Evaluation's Program Evaluation Standards is probably the most recognized and applied set of evaluation standards globally. The most recent edition of The Program Evaluation Standards includes five categories and 30 standards. The five categories are Utility, Feasibility, Propriety, Accuracy, and…

  10. Evaluation Strategies in Financial Education: Evaluation with Imperfect Instruments

    ERIC Educational Resources Information Center

    Robinson, Lauren; Dudensing, Rebekka; Granovsky, Nancy L.

    2016-01-01

    Program evaluation often suffers due to time constraints, imperfect instruments, incomplete data, and the need to report standardized metrics. This article about the evaluation process for the Wi$eUp financial education program showcases the difficulties inherent in evaluation and suggests best practices for assessing program effectiveness. We…

  11. Library Programs. Evaluating Federally Funded Public Library Programs.

    ERIC Educational Resources Information Center

    Office of Educational Research and Improvement (ED), Washington, DC.

    Following an introduction by Betty J. Turock, nine reports examine key issues in library evaluation: (1) "Output Measures and the Evaluation Process" (Nancy A. Van House) describes measurement as a concept to be understood in the larger context of planning and evaluation; (2) "Adapting Output Measures to Program Evaluation"…

  12. Responsive Meta-Evaluation: A Participatory Approach to Enhancing Evaluation Quality

    ERIC Educational Resources Information Center

    Sturges, Keith M.; Howley, Caitlin

    2017-01-01

    In an era of ever-deepening budget cuts and a concomitant demand for substantiated programs, many organizations have elected to conduct internal program evaluations. Internal evaluations offer advantages (e.g., enhanced evaluator program knowledge and ease of data collection) but may confront important challenges, including credibility threats,…

  13. When Unintended Consequences Become the Main Effect: Evaluating the Development of a Foster Parent Training Program.

    ERIC Educational Resources Information Center

    Loesch-Griffin, Deborah A.; Ringstaff, Cathy

    A program of education, training, and support provided to foster parents in a California county through a nonprofit agency is evaluated. The evaluators' experience indicates that: (1) evaluations are gaining in popularity; (2) role shifts by evaluators are sometimes difficult to perceive; (3) program staff are unlikely to use evaluative feedback…

  14. INSREC: Computational System for Quantitative Analysis of Radiation Effects Covering All Radiation Field

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dong Hoon Shin; Young Wook Lee; Young Ho Cho

    2006-07-01

    In the nuclear energy field, there are so many difficult things that even people who are working in this field are not much familiar with, such as, Dose evaluation, Dose management, etc. Thus, so many efforts have been done to achieve the knowledge and data for understanding. Although some data had been achieved, the applications of these data to necessary cases were more difficult job. Moreover, the type of Dose evaluation program until now was 'Console type' which is not easy enough to use for the beginners. To overcome the above causes of difficulties, the window-based integrated program and databasemore » management were developed in our research lab. The program, called as INSREC, consists of four sub-programs as follow; INSREC-NOM, INSREC-ACT, INSREC-MED, and INSREC-EXI. In ICONE 11 conference, INSREC-program(ICONE-36203) which can evaluates on/off-site dose of nuclear power plant in normal operation was introduced. Upgraded INSREC-program which will be presented in ICONE 14 conference has three additional codes comparing with pre-presented INSREC-program. Those subprograms can evaluate on/off-site Dose of nuclear power plant in accident cases. And they also have the functions of 'Dose evaluation and management' in the hospital and provide the 'Expert system' based on knowledge related to nuclear energy/radiation field. The INSREC-NOM, one of subprograms, is composed of 'Source term evaluation program', 'Atmospheric diffusion factor evaluation program', 'Off-site dose evaluation program', and 'On-site database program'. The INSREC-ACT is composed of 'On/Off-site dose evaluation program' and 'Result analysis program' and the INSREC-MED is composed of 'Workers/patients dose database program' and 'Dose evaluation program for treatment room'. The final one, INSREC-EXI, is composed of 'Database searching program based on artificial intelligence', 'Instruction program,' and 'FAQ/Q and A boards'. Each program was developed by using of Visual C++, Microsoft Access mainly. To verify the reliability, some suitable programs were selected such as AZAP and Stardose programs for the comparison. The AZAP program was selected for the on/off-site dose evaluation during the normal operation of nuclear reactor and Stardose program was used for the on/off-site dose evaluation in accident. The MCNP code was used for the dose evaluation and management in the hospital. Each comparison result was acceptable in errors analysis. According to the reliable verification results, it was concluded that INSREC program had an acceptable reliability for dose calculation and could give many proper dada for the sites. To serve the INSREC to people, the proper server system was constructed. We gave chances for the people (user) to utilize the INSREC through network connected to server system. The reactions were pretty much good enough to be satisfied. For the future work, many efforts will be given to improve the better user-interface and more necessary data will be provided to more people through database supplement and management. (authors)« less

  15. Evaluation of the Radiography Program at Caldwell Community College and Technical Institute--Summer, 1982.

    ERIC Educational Resources Information Center

    Pipes, V. David

    As part of a periodic evaluation of the occupational programs at Caldwell Community College and Technical Institute (CCC&TI), a study of the radiography program was conducted to collect information to facilitate planning, aid in program improvement, and meet accountability demands. The specific objectives of the program evaluation were to…

  16. Is Evaluative Research on Youth Suicide Programs Theory-Driven? The Canadian Experience.

    ERIC Educational Resources Information Center

    Breton, Jean-Jacques; Boyer, Richard; Bilodeau, Henriette; Raymond, Sylvaine; Joubert, Natacha; Nantel, Marie-Andree

    2002-01-01

    A review found that only 15 Canadian youth suicide programs were evaluated over the last decade. Descriptions of the programs were incomplete and theoretical bases for programs were not presented. Only two programs led to a reduction in suicidal behavior. Suggests that future evaluative research needs to place greater emphasis on content and…

  17. Guidelines "PEP," Peer Evaluation Program. A Systematic Approach for Evaluating Educational Programs, 1973-1974.

    ERIC Educational Resources Information Center

    Grotsky, Jeffery N.; And Others

    The Peer Evaluation Program (PEP) has been instituted by the Division of Special Education, Pennsylvania State Department of Education, to allow intermediate units an opportunity to continuously improve their programs. The advantages of the PEP system are: (1) it is a self-improvememt system of program development; (2) PEP allows local autonomy as…

  18. Handbook for Evaluating Drug and Alcohol Prevention Programs: Staff/Team Evaluation of Prevention Programs (STEPP).

    ERIC Educational Resources Information Center

    Hawkins, J. David; Nederhood, Britt

    This handbook was developed for the purpose of providing drug and alcohol prevention program managers with a comprehensive yet easy-to-use tool to help their evaluation efforts. The handbook emphasizes program staff members working together as a team. It provides instruments and activities for determining program effectiveness, as well as…

  19. Design and Operation of the Transformed National Healthy Start Evaluation.

    PubMed

    Banks, Jamelle E; Dwyer, Maura; Hirai, Ashley; Ghandour, Reem M; Atrash, Hani K

    2017-12-01

    Purpose Improving pregnancy outcomes for women and children is one of the nation's top priorities. The Healthy Start (HS) program was created to address factors that contribute to high infant mortality rates (IMRs) and persistent disparities in IMRs. The program began in 1991 and was transformed in 2014 to apply lessons from emerging research, past evaluation findings, and expert recommendations. To understand the implementation and impact of the transformed program, there is a need for a robust and comprehensive evaluation. Description The national HS evaluation will include an implementation evaluation, which will describe program components that affect outcomes; a utilization evaluation, which will examine the characteristics of women and infants who did and did not utilize the program; and an outcome evaluation, which will assess the program's effectiveness with regard to producing expected outcomes among the target population. Data sources include the National HS Program Survey, a HS participant survey, and individual-level program data linked to vital records and the Pregnancy Risk Assessment Monitoring System (PRAMS) survey. Assessment Descriptive analyses will be used to examine differences in risk profiles between participants and non-participants, as well as to calculate penetration rates for high-risk women in respective service areas. Multivariable analyses will be used to determine the impact of the program on key outcomes and will explore variation by dose, type of services received, and grantee characteristics. Conclusion Evaluation findings are expected to inform program decisions and direction, including identification of effective program components that can be spread and scaled.

  20. Evaluation of the Academic Occupational Program of the County of Leduc, From September, 1981 to June, 1984. Executive Summary.

    ERIC Educational Resources Information Center

    Nyberg, V. R.

    The paper reports results of an academic occupational program intended for educable mentally handicapped and learning disabled secondary students in Leduc, Alberta. An introduction reviews history of the program and the evaluation process. The evaluation plan, based on R. Stake's model for program evaluation, is described, and sources of data…

  1. Human Services Program Evaluation: "How to Improve Your Accountability and Program Effectiveness"

    ERIC Educational Resources Information Center

    Barrett, Thomas; Sorensen, James

    2015-01-01

    The term "outcome evaluation" has become one of the most popular terms among human service providers and those whose job it is to evaluate the impact of human service programs. In the public sector alone, there are over a hundred instruments in use to evaluate the impact of state human service programs. Most states, many providers, and…

  2. A multidimensional evaluation of a nursing information-literacy program.

    PubMed Central

    Fox, L M; Richter, J M; White, N E

    1996-01-01

    The goal of an information-literacy program is to develop student skills in locating, evaluating, and applying information for use in critical thinking and problem solving. This paper describes a multidimensional evaluation process for determining nursing students' growth in cognitive and affective domains. Results indicate improvement in student skills as a result of a nursing information-literacy program. Multidimensional evaluation produces a well-rounded picture of student progress based on formal measurement as well as informal feedback. Developing new educational programs can be a time-consuming challenge. It is important, when expending so much effort, to ensure that the goals of the new program are achieved and benefits to students demonstrated. A multidimensional approach to evaluation can help to accomplish those ends. In 1988, The University of Northern Colorado School of Nursing began working with a librarian to integrate an information-literacy component, entitled Pathways to Information Literacy, into the curriculum. This article describes the program and discusses how a multidimensional evaluation process was used to assess program effectiveness. The evaluation process not only helped to measure the effectiveness of the program but also allowed the instructors to use several different approaches to evaluation. PMID:8826621

  3. Resident Evaluation and Remediation: A Comprehensive Approach

    PubMed Central

    Wu, Jim S.; Siewert, Bettina; Boiselle, Phillip M.

    2010-01-01

    Background A comprehensive evaluation and remediation program is an essential component of any residency program. The evaluation system should identify problems accurately and early and allow residents with problems to be assigned to a remediation program that effectively deals with them. Elements of a proactive remediation program include a process for outlining deficiencies, providing resources for improvement, communicating clear goals for acceptable performance, and reevaluating performance against these goals. Intervention In recognition of the importance of early detection and prompt remediation of the struggling resident, we sought to develop a multifaceted approach to resident evaluation with the aim of early identification and prompt remediation of difficulties. This article describes our comprehensive evaluation program and remediation program, which uses resources within our radiology department and institutional graduate medical education office. Discussion An effective evaluation system should identify problems accurately and early, whereas a proactive remediation program should effectively deal with issues once they are identified. PMID:21975628

  4. Language Program Evaluation

    ERIC Educational Resources Information Center

    Norris, John M.

    2016-01-01

    Language program evaluation is a pragmatic mode of inquiry that illuminates the complex nature of language-related interventions of various kinds, the factors that foster or constrain them, and the consequences that ensue. Program evaluation enables a variety of evidence-based decisions and actions, from designing programs and implementing…

  5. Putting program evaluation into practice: enhancing the Girls Just Wanna Have Fun program.

    PubMed

    Bean, Corliss N; Kendellen, Kelsey; Halsall, Tanya; Forneris, Tanya

    2015-04-01

    In recent years there has been a call for increased community physical activity and sport programs for female youth that are deliberately structured to foster positive developmental outcomes. In addition, researchers have recognized the need to empirically evaluate such programs to ensure that youth are provided with optimal opportunities to thrive. This study represents a utilization-focused evaluation of Girls Just Wanna Have Fun, a female-only physical activity-based life skills community program. A utilization-focused evaluation is particularly important when the evaluation is to help stakeholders utilize the findings in practice. The purpose of this study was twofold: (a) to gain an understanding of the ongoing successes and challenges after year two of program implementation and (b) to examine how the adaptations made based on feedback from the first year evaluation were perceived as impacting the program. From interviews with youth participants and program leaders, three main themes with eight sub-themes emerged. The main themes were: (a) applying lessons learned can make a significant difference, (b) continually implementing successful strategies, and (c) ongoing challenges. Overall, this evaluation represents an important step in understanding how to improve program delivery to better meet the needs of the participants in community-based programming. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Evaluation of doctoral nursing programs in Japan by faculty members and their educational and research activities.

    PubMed

    Arimoto, Azusa; Gregg, Misuzu F; Nagata, Satoko; Miki, Yuko; Murashima, Sachiyo

    2012-07-01

    Evaluation of doctoral programs in nursing is becoming more important with the rapid increase in the programs in Japan. This study aimed to evaluate doctoral nursing programs by faculty members and to analyze the relationship of the evaluation with educational and research activities of faculty members in Japan. Target settings were all 46 doctoral nursing programs. Eighty-five faculty members from 28 programs answered the questionnaire, which included 17 items for program evaluation, 12 items for faculty evaluation, 9 items for resource evaluation, 3 items for overall evaluations, and educational and research activities. A majority gave low evaluations for sources of funding, the number of faculty members and support staff, and administrative systems. Faculty members who financially supported a greater number of students gave a higher evaluation for extramural funding support, publication, provision of diverse learning experiences, time of supervision, and research infrastructure. The more time a faculty member spent on advising doctoral students, the higher were their evaluations on the supportive learning environment, administrative systems, time of supervision, and timely feedback on students' research. The findings of this study indicate a need for improvement in research infrastructure, funding sources, and human resources to achieve quality nursing doctoral education in Japan. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Flight program language requirements. Volume 2: Requirements and evaluations

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The efforts and results are summarized for a study to establish requirements for a flight programming language for future onboard computer applications. Several different languages were available as potential candidates for future NASA flight programming efforts. The study centered around an evaluation of the four most pertinent existing aerospace languages. Evaluation criteria were established, and selected kernels from the current Saturn 5 and Skylab flight programs were used as benchmark problems for sample coding. An independent review of the language specifications incorporated anticipated future programming requirements into the evaluation. A set of detailed language requirements was synthesized from these activities. The details of program language requirements and of the language evaluations are described.

  8. Practical strategies for nursing education program evaluation.

    PubMed

    Lewallen, Lynne Porter

    2015-01-01

    Self-evaluation is required for institutions of higher learning and the nursing programs within them. The literature provides information on evaluation models and instruments, and descriptions of how specific nursing education programs are evaluated. However, there are few discussions in the nursing education literature of the practical aspects of nursing education program evaluation: how to get started, how to keep track of data, who to involve in data collection, and how to manage challenging criteria. This article discusses the importance of program evaluation in the academic setting and provides information on practical ways to organize the evaluation process and aggregate data, and strategies for gathering data from students, graduates, alumni, and employers of graduates. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Evaluation and capacity building to improve precollege science and mathematics achievement in the US: 10 CFR, Part 605. Technical progress report, June--December 1992

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1992-12-31

    The National Center for Improving Science Education has undertaken activities to achieve evaluation goals for DOE`s Precollege programs: develop means to determine program quality; develop means for determining the contribution of DOE precollege programs to both teacher enhancement and student achievement; provide evaluation designs and instruments and reports of program quality and impact; and strengthen both DOE`s and the Labs` capacity to do both short- and long-term planning as well as deliver effective programs and evaluation. Appendices include evaluation/technical assistance report, profiling teacher research participation and teacher development programs, teacher surveys, impact assessment design, and teacher research participation programs anecdotesmore » for 8 labs.« less

  10. The NLM evaluation lecture series: introduction to the special section on evaluating health communication programs.

    PubMed

    Logan, Robert A; Kreps, Gary L

    2014-12-01

    This article introduces the Journal of Health Communication's special section, Evaluating Health Communication Programs. This special section is based on a public lecture series supported by the National Library of Medicine titled "Better Health: Evaluating Health Communication Programs" designed to share best practices for using evaluation research to develop, implement, refine, and institutionalize the best health communication programs for promoting public health. This introduction provides an overview to the series, summarizes the major presentations in the series, and describe implications from the series for translational health communication research, interventions, and programs that can enhance health outcomes.

  11. Tailored program evaluation: Past, present, future.

    PubMed

    Suggs, L Suzanne; Cowdery, Joan E; Carroll, Jennifer B

    2006-11-01

    This paper discusses measurement issues related to the evaluation of computer-tailored health behavior change programs. As the first generation of commercially available tailored products is utilized in health promotion programming, programmers and researchers are becoming aware of the unique challenges that the evaluation of these programs presents. A project is presented that used an online tailored health behavior assessment (HBA) in a worksite setting. Process and outcome evaluation methods are described and include the challenges faced, and strategies proposed and implemented, for meeting them. Implications for future research in tailored program development, implementation, and evaluation are also discussed.

  12. Evaluation of the impact of the drug evaluation and classification program on enforcement and adjudication

    DOT National Transportation Integrated Search

    1992-12-01

    This study examined the effect of the Drug Evaluation and Classification (DEC) Program on impaired driving (DWI) enforcement and adjudication. Drug Recognition Experts (DREs) in DEC programs evaluate suspects when drugs other than alcohol are suspect...

  13. Program Evaluation: The Board Game--An Interactive Learning Tool for Evaluators

    ERIC Educational Resources Information Center

    Febey, Karen; Coyne, Molly

    2007-01-01

    The field of program evaluation lacks interactive teaching tools. To address this pedagogical issue, the authors developed a collaborative learning technique called Program Evaluation: The Board Game. The authors present the game and its development in this practitioner-oriented article. The evaluation board game is an adaptable teaching tool…

  14. The Nursing Leadership Institute program evaluation: a critique

    PubMed Central

    Havaei, Farinaz; MacPhee, Maura

    2015-01-01

    A theory-driven program evaluation was conducted for a nursing leadership program, as a collaborative project between university faculty, the nurses’ union, the provincial Ministry of Health, and its chief nursing officers. A collaborative logic model process was used to engage stakeholders, and mixed methods approaches were used to answer evaluation questions. Despite demonstrated, successful outcomes, the leadership program was not supported with continued funding. This paper examines what happened during the evaluation process: What factors failed to sustain this program? PMID:29355180

  15. A responsive evaluation of an Aboriginal nursing education access program.

    PubMed

    Curran, Vernon; Solberg, Shirley; LeFort, Sandra; Fleet, Lisa; Hollett, Ann

    2008-01-01

    Nursing education access programs have been introduced in a number of countries to address the shortage of healthcare providers of Aboriginal descent. An evaluation study of a nursing education access program in Labrador, Canada, was undertaken using a Responsive Evaluation approach. Interviews and focus groups with program stakeholders were conducted. Program effectiveness was influenced by culturally relevant curriculum, experiential and authentic learning opportunities, academic and social support, and the need for partnership building between stakeholders. The authors report key findings resulting from the Responsive Evaluation.

  16. Program Implementers' Evaluation of the Project P.A.T.H.S.: Findings Based on Different Datasets over Time

    PubMed Central

    Shek, Daniel T. L.; Ma, Cecilia M. S.

    2012-01-01

    This paper integrates the evaluation findings based on program implementers in nine datasets collected from 2005 to 2009 (244 schools and 7,926 implementers). Using consolidated data with schools as the unit of analysis, results showed that program implementers generally had positive perceptions of the program, themselves, and benefits of the program, with more than four-fifths of the implementers regarding the program as beneficial to the program participants. The subjective outcome evaluation instrument was found to be internally consistent. Multiple regression analyses revealed that perceived qualities of the program and program implementers predicted perceived effectiveness of the program. In conjunction with evaluation findings based on other sources, the present study provides support for the effectiveness of the Tier 1 Program of the Project P.A.T.H.S. (Positive Adolescent Training through Holistic Social Programmes) in Hong Kong. PMID:22629224

  17. Adult Literacy Education: Program Evaluation and Learner Assessment. Information Series No. 338.

    ERIC Educational Resources Information Center

    Lytle, Susan L.; Wolfe, Marcie

    Adult literacy programs need reliable information about program quality and effectiveness for accountability, improvement of practice, and expansion of knowledge. Evaluation and assessment reflect fundamental beliefs about adult learners, concepts of literacy, and educational settings. Resources for planning program evaluations include surveys,…

  18. Evaluating a Small-Group Counseling Program--A Model for Program Planning and Improvement in the Elementary Setting

    ERIC Educational Resources Information Center

    Bostick, Dee; Anderson, Ron

    2009-01-01

    School counselors are under increasing pressure to evaluate their programs in a manner consistent with teachers and other educators. A small-group counseling intervention was used by a school counselor as part of a three-level program planning initiative that illustrated best research practices to evaluate program outcomes. Forty-nine third-grade…

  19. Using a Non-Equivalent Groups Quasi Experimental Design to Reduce Internal Validity Threats to Claims Made by Math and Science K-12 Teacher Recruitment Programs

    NASA Astrophysics Data System (ADS)

    Moin, Laura

    2009-10-01

    The American Recovery and Reinvestment Act national policy established in 2009 calls for ``meaningful data'' that demonstrate educational improvements, including the recruitment of high-quality teachers. The scant data available and the low credibility of many K-12 math/science teacher recruitment program evaluations remain the major barriers for the identification of effective recruitment strategies. Our study presents a methodology to better evaluate the impact of recruitment programs on increasing participants' interest in teaching careers. The research capitalizes on the use of several control groups and presents a non-equivalent groups quasi-experimental evaluation design that produces program effect claims with higher internal validity than claims generated by current program evaluations. With this method that compares responses to a teaching career interest question from undergraduates all along a continuum from just attending an information session to participating (or not) in the recruitment program, we were able to compare the effect of the program in increasing participants' interest in teaching careers versus the evolution of the same interest but in the absence of the program. We were also able to make suggestions for program improvement and further research. While our findings may not apply to other K-12 math/science teacher recruitment programs, we believe that our evaluation methodology does and will contribute to conduct stronger program evaluations. In so doing, our evaluation procedure may inform recruitment program designers and policy makers.

  20. Evaluation of a peer assessment approach for enhancing the organizational capacity of state injury prevention programs.

    PubMed

    Hunter, Wanda M; Schmidt, Ellen R; Zakocs, Ronda

    2005-01-01

    To conduct a formative and pilot impact evaluation of the State Technical Assessment Team (STAT) program, a visitation-based (visitatie) peer assessment program designed to enhance the organizational capacity of state health department injury prevention programs. The formative evaluation was based on observational, record review, and key informant interview data collected during the implementation of the first 7 STAT visits. Pilot impact data were derived from semi-structured interviews with state injury prevention personnel one year after the visit. Formative evaluation identified 6 significant implementation problems in the first visits that were addressed by the program planners, resulting in improvements to the STAT assessment protocol. Impact evaluation revealed that after one year, the 7 state injury prevention programs had acted on 81% of the recommendations received during their STAT visits. All programs reported gains in visibility and credibility within the state health department and increased collaboration and cooperation with other units and agencies. Other significant program advancements were also reported. Specific program standards and review procedures are important to the success of peer assessment programs such as STAT. Early impact evaluation suggests that peer assessment protocols using the visitatie model can lead to gains in organizational capacity.

  1. Housing First and Photovoice: Transforming Lives, Communities, and Systems

    PubMed Central

    Barile, John P.; Ogawa, Terry Yasuko; Peralta, Nelson; Bugg, Reumell; Lau, John; Lamberton, Thomas; Hall, Corazon; Mori, Victor

    2018-01-01

    This article presents findings from a community-based participatory evaluation of a Housing First program on the Island of O’ahu. In this study, clients in a Housing First program used Photovoice to evaluate the program and to advocate for progressive housing policies. Written together by members of the Housing First Photovoice group, this collaborative article describes the outcomes from both the Housing First program and the Photovoice project and demonstrates the ways in which participatory program evaluations can interact with client-driven programs like Housing First to produce a cumulative, transformative impact. Findings suggest that community psychologists hoping to re-engage with community mental health systems through enacting transformative change should consider taking a community-based participatory approach to program evaluation because increased client voice in community mental health programs and their evaluations can have far-reaching, transformative impacts for research, practice, and policy. PMID:29323410

  2. An Interprofessional Program Evaluation Case Study: Utilizing Multiple Measures To Assess What Matters. AIR 1997 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Delaney, Anne Marie

    This paper reviews the first two years of a model program-evaluation case study which is intended to show: (1) how program evaluation can contribute to academic and professional degree programs; (2) how qualitative and quantitative techniques can be used to produce reliable measures for evaluation studies; and (3) how the role of the institutional…

  3. Exploring the Suitability of an English for Health Sciences Program: Model and Report of a Self-Evaluation Process

    ERIC Educational Resources Information Center

    Ferrer, Erica; Pérez, Yuddy

    2017-01-01

    Program evaluation is a process of carefully collecting information in order to make informed decisions to strengthen specific components of a given program. The type of evaluation an institution decides to undertake depends on the purpose as well as on the information the institution wants to find out about its program. Self-evaluation represents…

  4. Motivation for Evaluation: A roadmap for Improving Program Efficacy

    NASA Astrophysics Data System (ADS)

    Taber, J. J.; Bohon, W.; Bravo, T. K.; Dorr, P. M.; Hubenthal, M.; Johnson, J. A.; Sumy, D. F.; Welti, R.; Davis, H. B.

    2016-12-01

    Over the past year, the Incorporated Research Institutions for Seismology (IRIS) Education and Public Outreach (EPO) program has undertaken a new effort to increase the rigor with which it evaluates its programs and products. More specifically we sought to make evaluation an integral part of our EPO staff's work, enable staff to demonstrate why we do the activities we do, enhance the impact or our products and programs, and empower staff to be able to make evidence-based claims. The challenges we faced included a modest budget, finding an applicable approach to both new and legacy programs ranging from formal and informal education to public outreach, and implementing the process without overwhelming staff. The Collaborative Impact Analysis Method (IAM; Davis and Scalice, 2015) was selected as it allowed us to combine the EPO staff's knowledge of programs, audiences and content with the expertise of an outside evaluation expert, through consultations and a qualitative rubric assessing the initial state of each product/program's evaluation. Staff then developed action plans to make incremental improvements to the evaluation of programs over time. We have found that this approach promotes the development of staff knowledge and skills regarding evaluation, provides a common language among staff, increases enthusiasm to collect and share data, encourages discussions of evaluative approaches when planning new activities, and improves each program's ability to capture the intended and unintended effects on the behaviors, attitudes, skills, interests, and/or knowledge of users/participants. We will share the initial IAM Scores for products and programs in the EPO portfolio, along with examples of the action plans for several key products and programs, and the impact that implementing those actions plans has had on our evaluations. Davis, H. & Scalice, D. (2015). Evaluate the Impact of your Education and Outreach Program Using the Quantitative Collaborative Impact Analysis Method (Invited). Abstract ED53D-0871 presented at 2015 Fall Meeting, AGU, San Francisco, Calif., 14 - 18 Dec.

  5. Conceptual framework for development of comprehensive e-health evaluation tool.

    PubMed

    Khoja, Shariq; Durrani, Hammad; Scott, Richard E; Sajwani, Afroz; Piryani, Usha

    2013-01-01

    The main objective of this study was to develop an e-health evaluation tool based on a conceptual framework including relevant theories for evaluating use of technology in health programs. This article presents the development of an evaluation framework for e-health programs. The study was divided into three stages: Stage 1 involved a detailed literature search of different theories and concepts on evaluation of e-health, Stage 2 plotted e-health theories to identify relevant themes, and Stage 3 developed a matrix of evaluation themes and stages of e-health programs. The framework identifies and defines different stages of e-health programs and then applies evaluation theories to each of these stages for development of the evaluation tool. This framework builds on existing theories of health and technology evaluation and presents a conceptual framework for developing an e-health evaluation tool to examine and measure different factors that play a definite role in the success of e-health programs. The framework on the horizontal axis divides e-health into different stages of program implementation, while the vertical axis identifies different themes and areas of consideration for e-health evaluation. The framework helps understand various aspects of e-health programs and their impact that require evaluation at different stages of the life cycle. The study led to the development of a new and comprehensive e-health evaluation tool, named the Khoja-Durrani-Scott Framework for e-Health Evaluation.

  6. An Overview of the National Nutrition Education and Training Program Evaluation.

    ERIC Educational Resources Information Center

    St. Pierre, Robert G.; Rezmovic, Victor

    1982-01-01

    Presents the organizing framework used in evaluating the National Nutrition Education and Training Program (NET) and summarizes the descriptive, evaluative, and meta-evaluative findings. Concludes that positive effects on children's nutrition-related knowledge have resulted from different nutrition education programs. (DC)

  7. Documenting Progress and Demonstrating Results: Evaluating Local Out-of-School Time Programs.

    ERIC Educational Resources Information Center

    Little, Priscilla; DuPree, Sharon; Deich, Sharon

    A collaborative publication between Harvard Family Research Project and The Finance Project, this brief offers guidance in documenting progress and demonstrating results in local out-of-school-time programs. Following introductory remarks providing a rationale for program evaluation, discussing principles of program evaluation, and clarifying key…

  8. What Do We Know about School-Based Management?

    ERIC Educational Resources Information Center

    Patrinos, Harry Anthony; Fasih, Tazeen; Barrera, Felipe; Garcia-Moreno, Vicente A.; Bentaouet-Kattan, Raja; Baksh, Shaista; Wickramasekera, Inosha

    2007-01-01

    Impact evaluations of school-based management (SBM) programs, or any other kind of program, are important because they can demonstrate whether or not the program has accomplished its objectives. Furthermore, these evaluations can identify ways to improve the design of the program. These evaluations can also make successful interventions…

  9. 40 CFR 51.353 - Network type and program evaluation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Network type and program evaluation. 51... Requirements § 51.353 Network type and program evaluation. Basic and enhanced I/M programs can be centralized.... (a) Presumptive equivalency. A decentralized network consisting of stations that only perform...

  10. Creating an Information Literacy Badges Program in Blackboard: A Formative Program Evaluation

    ERIC Educational Resources Information Center

    Tunon, Johanna; Ramirez, Laura Lucio; Ryckman, Brian; Campbell, Loy; Mlinar, Courtney

    2015-01-01

    A formative program evaluation using Stufflebeam's (2010) Context, Input, Process, Product (CIPP) model was conducted to assess the use of digital badges for tracking basic library instructional skills across academic programs at Nova Southeastern University. Based on the evaluation of pilot library modules and Blackboard Learn's badges…

  11. 29 CFR 1960.79 - Self-evaluations of occupational safety and health programs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 9 2012-07-01 2012-07-01 false Self-evaluations of occupational safety and health programs. 1960.79 Section 1960.79 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs...

  12. 29 CFR 1960.79 - Self-evaluations of occupational safety and health programs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 9 2014-07-01 2014-07-01 false Self-evaluations of occupational safety and health programs. 1960.79 Section 1960.79 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs...

  13. 29 CFR 1960.79 - Self-evaluations of occupational safety and health programs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 9 2013-07-01 2013-07-01 false Self-evaluations of occupational safety and health programs. 1960.79 Section 1960.79 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs...

  14. 29 CFR 1960.79 - Self-evaluations of occupational safety and health programs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 9 2011-07-01 2011-07-01 false Self-evaluations of occupational safety and health programs. 1960.79 Section 1960.79 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs...

  15. Home-Start between Childhood and Maturity: A Programme Evaluation.

    ERIC Educational Resources Information Center

    Terpstra, Linda; van Dijke, Anke

    A crucial question for evaluating nationally or internationally implemented programs is whether local adaptations detract from program quality and effectiveness. An evaluation examined the program successes and challenges encountered in the first 5 years of Home-Start in the Netherlands, a home-based family support program for families with young…

  16. Maryland Community Colleges 1980 Program Evaluations.

    ERIC Educational Resources Information Center

    Maryland State Board for Community Colleges, Annapolis.

    This report contains qualitative evaluations of 48 programs throughout the Maryland community college system, as well as a statewide evaluation of Teacher Education transfer programs. A summary of the Teacher Education programs is presented first, in which the purpose and role of teacher education in the community college, enrollment trends,…

  17. 29 CFR 1960.79 - Self-evaluations of occupational safety and health programs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Self-evaluations of occupational safety and health programs. 1960.79 Section 1960.79 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... AND HEALTH PROGRAMS AND RELATED MATTERS Evaluation of Federal Occupational Safety and Health Programs...

  18. Evaluating a physician leadership development program - a mixed methods approach.

    PubMed

    Throgmorton, Cheryl; Mitchell, Trey; Morley, Tom; Snyder, Marijo

    2016-05-16

    Purpose - With the extent of change in healthcare today, organizations need strong physician leaders. To compensate for the lack of physician leadership education, many organizations are sending physicians to external leadership programs or developing in-house leadership programs targeted specifically to physicians. The purpose of this paper is to outline the evaluation strategy and outcomes of the inaugural year of a Physician Leadership Academy (PLA) developed and implemented at a Michigan-based regional healthcare system. Design/methodology/approach - The authors applied the theoretical framework of Kirkpatrick's four levels of evaluation and used surveys, observations, activity tracking, and interviews to evaluate the program outcomes. The authors applied grounded theory techniques to the interview data. Findings - The program met targeted outcomes across all four levels of evaluation. Interview themes focused on the significance of increasing self-awareness, building relationships, applying new skills, and building confidence. Research limitations/implications - While only one example, this study illustrates the importance of developing the evaluation strategy as part of the program design. Qualitative research methods, often lacking from learning evaluation design, uncover rich themes of impact. The study supports how a PLA program can enhance physician learning, engagement, and relationship building throughout and after the program. Physician leaders' partnership with organization development and learning professionals yield results with impact to individuals, groups, and the organization. Originality/value - Few studies provide an in-depth review of evaluation methods and outcomes of physician leadership development programs. Healthcare organizations seeking to develop similar in-house programs may benefit applying the evaluation strategy outlined in this study.

  19. Collaborative evaluation of a high school prevention curriculum: How methods of collaborative evaluation enhanced a randomized control trial to inform program improvement.

    PubMed

    Orsini, Muhsin Michael; Wyrick, David L; Milroy, Jeffrey J

    2012-11-01

    Blending high-quality and rigorous research with pure evaluation practice can often be best accomplished through thoughtful collaboration. The evaluation of a high school drug prevention program (All Stars Senior) is an example of how perceived competing purposes and methodologies can coexist to investigate formative and summative outcome variables that can be used for program improvement. Throughout this project there were many examples of client learning from evaluator and evaluator learning from client. This article presents convincing evidence that collaborative evaluation can improve the design, implementation, and findings of the randomized control trial. Throughout this paper, we discuss many examples of good science, good evaluation, and other practical benefits of practicing collaborative evaluation. Ultimately, the authors created the term pre-formative evaluation to describe the period prior to data collection and before program implementation, when collaborative evaluation can inform program improvement. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. National Weatherization Assistance Program Characterization - Describing the Pre-ARRA Progam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bensch, Ingo; Keene, Ashleigh; Cowan, Claire

    2014-09-01

    This report characterizes the Department of Energy s Weatherization Assistance Program (WAP) as it was administered in Program Year 2008. WAP has supported energy efficiency improvements to the homes of low-income households in the United States since 1976. The program provides grants, guidance, and other support to grantees: weatherization programs administered by each of the 50 states, the District of Columbia and some Native American tribes. Although there have been studies of some grantee-administered weatherization programs, the overall effectiveness of the national weatherization program has not been formally evaluated since Program Year 1989. Since that time, the program has evolvedmore » significantly, with an increased focus on baseload electric usage, continued evolution of diagnostic tools, new guidelines and best practices for heating-related measures, and adjustments in program rules. More recently, the program has also adjusted to large, temporary funding increases and changes in federal rules spurred by the American Recovery and Reinvestment Act (ARRA). Because the Weatherization Assistance Program of today is dramatically different from the one evaluated in 1989, DOE determined to undertake a new comprehensive evaluation of the national program. This new national evaluation is managed by Oak Ridge National Laboratory (ORNL). Under a competitive solicitation process, ORNL selected APPRISE, Inc., Blasnik & Associates, Dalhoff Associates and the Energy Center of Wisconsin to conduct the evaluation. The national evaluation comprises two independent evaluations. The first evaluation of which this report is a part focuses on Program Year 2008 (PY08). The second evaluation focuses on the ARRA-funded years of 2009 through 2011. This report, together with its companion the Eligible Population Study addresses specific program characterization goals established for the greater evaluation. The Energy Center led grantee and subgrantee data collection efforts, administering surveys to 51 grantees and 851 of the approximately 900 subgrantees that were slated to receive DOE weatherization funds in PY08. In all, seven different data collection instruments were used to gather the needed data two instruments for grantees and five for subgrantees. See Table 1 for a list of these survey instruments. These surveys were used to determine, among other things: Structure and funding of weatherization programs Training and staff development of service providers How weatherization services are delivered Clients served« less

  1. Intern evaluation strategies in family medicine residency education: what is-and is not-being done.

    PubMed

    Yates, Jennifer E

    2013-06-01

    Family medicine interns often have deficiencies that are not initially appreciated. By recognizing those growth opportunities early, programs may be able to better meet their interns' training needs. This study provides a needs assessment to ascertain what evaluation tools are being utilized by residency programs to assess their incoming interns. A questionnaire was sent to all US family medicine residency program coordinators (439 programs) via Survey Monkey© inquiring about whether intern evaluation is performed and, if so, what strategies are used. A mixed mode methodology was used: mailing with incentive, email prompts, and telephone calls. Of 439 programs, 220 (50%) responded to the survey. Most respondents (145, 66%) think intern evaluation is needed. However, only 79 (36%) programs are actually doing intern evaluations-only 14 (6.4%) extensively. Most programs are performing simulations (81, 45%) and assessing knowledge/comfort levels (79, 36%); less than one third are considering personality/learning styles, and almost no programs are evaluating skills such as typing (three, 1.4%) and math (one, 0.5%). Many programs use evaluations to guide future planning, help with early identification of challenging learners, and to match training to the residents' needs. Several programs expressed concern about how they would use the information once obtained. The majority of respondents agreed that a baseline intern evaluation is useful; few are actually doing it. This area is not well-described in the literature; residency programs could benefit from information sharing. The next step is to encourage interest in and implementation of such strategies.

  2. Process Evaluation for Improving K12 Program Effectiveness: Case Study of a National Institutes of Health Building Interdisciplinary Research Careers in Women's Health Research Career Development Program.

    PubMed

    Raymond, Nancy C; Wyman, Jean F; Dighe, Satlaj; Harwood, Eileen M; Hang, Mikow

    2018-06-01

    Process evaluation is an important tool in quality improvement efforts. This article illustrates how a systematic and continuous evaluation process can be used to improve the quality of faculty career development programs by using the University of Minnesota's Building Interdisciplinary Research Careers in Women's Health (BIRCWH) K12 program as an exemplar. Data from a rigorous process evaluation incorporating quantitative and qualitative measurements were analyzed and reviewed by the BIRCWH program leadership on a regular basis. Examples are provided of how this evaluation model and processes were used to improve many aspects of the program, thereby improving scholar, mentor, and advisory committee members' satisfaction and scholar outcomes. A rigorous evaluation plan can increase the effectiveness and impact of a research career development plan.

  3. Using an Evaluability Assessment To Select Methods for Evaluating State Technology Development Programs: The Case of the Georgia Research Alliance.

    ERIC Educational Resources Information Center

    Youtie, Jan; Bozeman, Barry; Shapira, Philip

    1999-01-01

    Describes an evaluability assessment of the Georgia Research Alliance (GRA), a technology development program. Presents the steps involved in conducting an evaluability assessment, including development of an understanding of the program and its stakeholders. Analyzes and compares different methods by which the GRA could be evaluated. (SLD)

  4. Indian Economic Development: An Evaluation of EDA's Selected Indian Reservation Program. Volume II: Individual Reservation Reports, Appendices.

    ERIC Educational Resources Information Center

    Boise Cascade Center for Community Development, ID.

    As the appendices to an evaluation of the Economic Development Administration's (EDA) Selected Indian Reservation Program, this portion of the evaluation report presents individualized evaluations of each of the 16 reservations originally selected for the program in 1967. Each reservation evaluation is presented in terms of the following format:…

  5. Data Collection Methods for Evaluating Museum Programs and Exhibitions

    ERIC Educational Resources Information Center

    Nelson, Amy Crack; Cohn, Sarah

    2015-01-01

    Museums often evaluate various aspects of their audiences' experiences, be it what they learn from a program or how they react to an exhibition. Each museum program or exhibition has its own set of goals, which can drive what an evaluator studies and how an evaluation evolves. When designing an evaluation, data collection methods are purposefully…

  6. Continuous Evaluation in Ethics Education: A Case Study.

    PubMed

    McIntosh, Tristan; Higgs, Cory; Mumford, Michael; Connelly, Shane; DuBois, James

    2018-04-01

    A great need for systematic evaluation of ethics training programs exists. Those tasked with developing an ethics training program may be quick to dismiss the value of training evaluation in continuous process improvement. In the present effort, we use a case study approach to delineate how to leverage formative and summative evaluation measures to create a high-quality ethics education program. With regard to formative evaluation, information bearing on trainee reactions, qualitative data from the comments of trainees, in addition to empirical findings, can ensure that the training program operates smoothly. Regarding summative evaluation, measures examining trainee cognition, behavior, and organization-level results provide information about how much trainees have changed as a result of taking the ethics training. The implications of effective training program evaluation are discussed.

  7. An evaluation toolkit for Florida's Commuter Assistance Programs (CAP) : a companion to the 1999 CAP evaluation manual

    DOT National Transportation Integrated Search

    2001-01-01

    This manual is a companion piece to the Commuter Assistance Program Evaluation Manual that was developed to assist Florida's Commuter Assistance Programs (CAP) in their efforts to measure and evaluate their performance. This manual is intended to pro...

  8. Alternative Designs for Evaluating Workplace Literacy Programs. Conference Proceedings and Commissioned Papers at the "Design Guidance for Evaluating Workplace Literacy Programs" Work Group Conference (Washington, D.C. April 13, 1993).

    ERIC Educational Resources Information Center

    Research Triangle Inst., Research Triangle Park, NC.

    This document contains the five papers presented at a meeting at which key issues in evaluating workplace literacy programs were discussed. In "Key Components of Workplace Liteacy Projects and Definitions of Project 'Modules,'" Judith A. Alamprese describes the context for evaluating the National Extension Program, components of workplace literacy…

  9. Multimethod Strategy for Assessing Program Fidelity: The National Evaluation of the Revised G.R.E.A.T. Program

    ERIC Educational Resources Information Center

    Esbensen, Finn-Aage; Matsuda, Kristy N.; Taylor, Terrance J.; Peterson, Dana

    2011-01-01

    This study reports the results of the process evaluation component of the Process and Outcome Evaluation of the Gang Resistance Education and Training (G.R.E.A.T.) program. The process evaluation consisted of multiple methods to assess program fidelity: (a) observations of G.R.E.A.T. Officer Trainings (G.O.T); (b) surveys and interviews of…

  10. Phoenix Rising: use of a participatory approach to evaluate a federally funded HIV, hepatitis and substance abuse prevention program.

    PubMed

    Dryden, Eileen; Hyde, Justeen; Livny, Ayala; Tula, Monique

    2010-11-01

    This paper highlights the value of utilizing a participatory evaluation approach when working with community agencies receiving federal funding for prevention and intervention services. Drawing from our experience as evaluators of a SAMHSA-funded substance abuse, HIV and Hepatitis prevention program targeting homeless young adults, we describe the importance of and strategies for creating a participatory evaluation partnership with program implementers. By participatory evaluation we mean the active involvement of program implementers in defining the evaluation, developing instruments, collecting data, discussing findings, and disseminating results. There are a number of challenges faced when using this approach with federally funded programs that require the use of standardized measurement tools and data collection procedures. Strategies we used to strike a balance between federal requirements and local needs are presented. By increasing the understanding of and participation in the evaluation process, program implementers have greater support for data collection requirements and are appreciably more interested in learning from the evaluation data. This approach has helped to build the capacity of a program and stimulated new possibilities for learning, growing, and ultimately improving the services offered to those the program strives to reach. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  11. Potential pros and cons of external healthcare performance evaluation systems: real-life perspectives on Iranian hospital evaluation and accreditation program.

    PubMed

    Jaafaripooyan, Ebrahim

    2014-09-01

    Performance evaluation is essential to quality improvement in healthcare. The current study has identified the potential pros and cons of external healthcare evaluation programs, utilizing them subsequently to look into the merits of a similar case in a developing country. A mixed method study employing both qualitative and quantitative data collection and analysis techniques was adopted to achieve the study end. Subject Matter Experts (SMEs) and professionals were approached for two-stage process of data collection. Potential advantages included greater attractiveness of high accreditation rank healthcare organizations to their customers/purchasers and boosted morale of their personnel. Downsides, as such, comprised the programs' over-reliance on value judgment of surveyors, routinization and incurring undue cost on the organizations. In addition, the improved, standardized care processes as well as the judgmental nature of program survey were associated, as pros and cons, to the program investigated by the professionals. Besides rendering a tentative assessment of Iranian hospital evaluation program, the study provides those running external performance evaluations with a lens to scrutinize the virtues of their own evaluation systems through identifying the potential advantages and drawbacks of such programs. Moreover, the approach followed could be utilized for performance assessment of similar evaluation programs.

  12. An Evaluation of the Right Choices Program to Determine Effectiveness in Delivering Constructive Interventions and Providing an Early Support Program in Order to Modify Behavior of First-Time Student Offenders Who Commit Drug and Violent Acts

    ERIC Educational Resources Information Center

    Barnes, Lisa B.

    2010-01-01

    The purpose of the study was to perform a program evaluation of the Right Choices Program to determine the program's effectiveness in delivering constructive interventions that modify student behavior once students have left the program and have returned to their regular learning environment. This mixed-method evaluation consisted of an…

  13. Experiments in evaluation capacity building: Enhancing brain disorders research impact in Ontario.

    PubMed

    Nylen, Kirk; Sridharan, Sanjeev

    2017-05-08

    This paper is the introductory paper on a forum on evaluation capacity building for enhancing impacts of research on brain disorders. It describes challenges and opportunities of building evaluation capacity among community-based organizations in Ontario involved in enhancing brain health and supporting people living with a brain disorder. Using an example of a capacity building program called the "Evaluation Support Program", which is run by the Ontario Brain Institute, this forum discusses multiple themes including evaluation capacity building, evaluation culture and evaluation methodologies appropriate for evaluating complex community interventions. The goal of the Evaluation Support Program is to help community-based organizations build the capacity to demonstrate the value that they offer in order to improve, sustain, and spread their programs and activities. One of the features of this forum is that perspectives on the Evaluation Support Program are provided by multiple stakeholders, including the community-based organizations, evaluation team members involved in capacity building, thought leaders in the fields of evaluation capacity building and evaluation culture, and the funders. Copyright © 2017. Published by Elsevier Ltd.

  14. A review of elementary school-based substance use prevention programs: identifying program attributes.

    PubMed

    Hopfer, S; Davis, D; Kam, J A; Shin, Y; Elek, E; Hecht, M L

    2010-01-01

    This article takes a systematic approach to reviewing substance use prevention programs introduced in elementary school (K-6th grade). Previous studies evaluating such programs among elementary school students showed mixed effects on subsequent substance use and related psychosocial factors. Thirty published evaluation studies of 24 elementary school-based substance use prevention programs were reviewed. The study selection criteria included searching for program evaluations from 1980 to 2008. Among 27 evaluation studies that examined program effects on substance use, 56% (n = 15) found significant decreases. In addition, programs most often demonstrated effects on increasing negative substance use attitudes, increasing knowledge, decreasing perceptions of prevalence rates (i.e., descriptive norms), and improving resistance skills. These results have implications for the appropriateness and value of introducing substance use prevention programs to youth in elementary school.

  15. Reaching Your Program Goals: The Secret to a Successful Relationship with Your Evaluator

    NASA Astrophysics Data System (ADS)

    Warburton, J.; Crowley, S.; Larson, A.

    2012-12-01

    PolarTREC (Teachers and Researchers Exploring and Collaborating) is a National Science Foundation (NSF) funded program in which K-12 teachers participate in hands-on field research experiences in the Polar Regions. PolarTREC has become a leader in the evaluation of teacher research experiences (TREs) and offers a model for outside evaluation for education and public outreach. Programs such as TRE's offer a direct package of outreach opportunities for effective broader impacts. This presentation offers a model for the evaluative process beginning with project design and goals, which involve an outside evaluator, and that provide funders with an outlined scope of projects as well as outcomes and products for use by the public to advance scientific understanding. Outcomes are determined before the program is developed to ensure that all components are striving for program efficacy. Formative and summative evaluations for all audiences ensure robust program reports via survey's, knowledge assessments, conference calls, outreach implementation plans for multiple diverse audiences and in-depth case studies with teachers back in their classrooms. PolarTREC has become part of a larger, international working group of evaluators and program managers on program assessment. As part of this working group, sharing best practices for effective evaluation to better support science efforts, inform funders, and communicate with the public, has been integral to the evolution and advancement of our successful evaluation model.

  16. Evaluation of ridesharing programs in Michigan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kulp, G.; Tsao, H.J.; Webber, R.E.

    1982-10-01

    The design, implementation, and results of a carpool and vanpool evaluation are described. Objectives of the evaluation were: to develop credible estimates of the energy savings attributable to the ridesharing program, to provide information for improving the performance of the ridesharing program, and to add to a general understanding of the ridesharing process. Previous evaluation work is critiqued and the research methodology adopted for this study is discussed. The ridesharing program in Michigan is described and the basis for selecting Michigan as the evaluation site is discussed. The evaluation methodology is presented, including research design, sampling procedure, data collection, andmore » data validation. Evaluation results are analyzed. (LEW)« less

  17. Strategies for Evaluating a Freshman Studies Program.

    ERIC Educational Resources Information Center

    Ketkar, Kusum; Bennett, Shelby D.

    1989-01-01

    The study developed an economic model for the evaluation of Seaton Hall University's freshman studies program. Two techniques used to evaluate the economic success of the program are break-even analysis and elasticity coefficient. (Author/MLW)

  18. 1999 commuter assistance program evaluation manual

    DOT National Transportation Integrated Search

    2001-01-01

    This manual was developed to assist Florida's Commuter Assistance Programs (CAP) to measure and evaluate their performance. It provides information necessary for a CAP to create and implement its own evaluation program. It discusses performance measu...

  19. Purposive Facebook Recruitment Endows Cost-Effective Nutrition Education Program Evaluation

    PubMed Central

    Wamboldt, Patricia

    2013-01-01

    Background Recent legislation established a requirement for nutrition education in federal assistance programs to be evidence-based. Recruitment of low-income persons to participate and evaluate nutrition education activities can be challenging and costly. Facebook has been shown to be a cost-effective strategy to recruit this target audience to a nutrition program. Objective The purpose of our study was to examine Facebook as a strategy to recruit participants, especially Supplemental Nutrition Assistance Program Education (SNAP-Ed) eligible persons, to view and evaluate an online nutrition education program intended to be offered as having some evidence base for SNAP-Ed programming. Methods English-speaking, low-income Pennsylvania residents, 18-55 years with key profile words (eg, Supplemental Nutrition Assistance Program, Food bank), responded to a Facebook ad inviting participation in either Eating Together as a Family is Worth It (WI) or Everyone Needs Folic Acid (FA). Participants completed an online survey on food-related behaviors, viewed a nutrition education program, and completed a program evaluation. Facebook set-up functions considered were costing action, daily spending cap, and population reach. Results Respondents for both WI and FA evaluations were similar; the majority were white, <40 years, overweight or obese body mass index, and not eating competent. A total of 807 Facebook users clicked on the WI ad with 73 unique site visitors and 47 of them completing the program evaluation (ie, 47/807, 5.8% of clickers and 47/73, 64% of site visitors completed the evaluation). Cost per completed evaluation was US $25.48; cost per low-income completer was US $39.92. Results were similar for the FA evaluation; 795 Facebook users clicked on the ad with 110 unique site visitors, and 73 completing the evaluation (ie, 73/795, 9.2% of ad clickers and 73/110, 66% of site visitors completed the evaluation). Cost per valid completed survey with program evaluation was US $18.88; cost per low-income completer was US $27.53. Conclusions With Facebook we successfully recruited low-income Pennsylvanians to online nutrition program evaluations. Benefits using Facebook as a recruitment strategy included real-time recruitment management with lower costs and more efficiency compared to previous data from traditional research recruitment strategies reported in the literature. Limitations prompted by repeated survey attempts need to be addressed to optimize this recruitment strategy. PMID:23948573

  20. Purposive facebook recruitment endows cost-effective nutrition education program evaluation.

    PubMed

    Lohse, Barbara; Wamboldt, Patricia

    2013-08-15

    Recent legislation established a requirement for nutrition education in federal assistance programs to be evidence-based. Recruitment of low-income persons to participate and evaluate nutrition education activities can be challenging and costly. Facebook has been shown to be a cost-effective strategy to recruit this target audience to a nutrition program. The purpose of our study was to examine Facebook as a strategy to recruit participants, especially Supplemental Nutrition Assistance Program Education (SNAP-Ed) eligible persons, to view and evaluate an online nutrition education program intended to be offered as having some evidence base for SNAP-Ed programming. English-speaking, low-income Pennsylvania residents, 18-55 years with key profile words (eg, Supplemental Nutrition Assistance Program, Food bank), responded to a Facebook ad inviting participation in either Eating Together as a Family is Worth It (WI) or Everyone Needs Folic Acid (FA). Participants completed an online survey on food-related behaviors, viewed a nutrition education program, and completed a program evaluation. Facebook set-up functions considered were costing action, daily spending cap, and population reach. Respondents for both WI and FA evaluations were similar; the majority were white, <40 years, overweight or obese body mass index, and not eating competent. A total of 807 Facebook users clicked on the WI ad with 73 unique site visitors and 47 of them completing the program evaluation (ie, 47/807, 5.8% of clickers and 47/73, 64% of site visitors completed the evaluation). Cost per completed evaluation was US $25.48; cost per low-income completer was US $39.92. Results were similar for the FA evaluation; 795 Facebook users clicked on the ad with 110 unique site visitors, and 73 completing the evaluation (ie, 73/795, 9.2% of ad clickers and 73/110, 66% of site visitors completed the evaluation). Cost per valid completed survey with program evaluation was US $18.88; cost per low-income completer was US $27.53. With Facebook we successfully recruited low-income Pennsylvanians to online nutrition program evaluations. Benefits using Facebook as a recruitment strategy included real-time recruitment management with lower costs and more efficiency compared to previous data from traditional research recruitment strategies reported in the literature. Limitations prompted by repeated survey attempts need to be addressed to optimize this recruitment strategy.

  1. Achievement Testing of Disadvantaged and Minority Students for Educational Program Evaluation.

    ERIC Educational Resources Information Center

    Wargo, Michael J., Ed.; Green, Donald Ross, Ed.

    The following papers were delivered: Introductory Remarks, John W. Evans; An Evaluator's Perspective, Michael J. Wargo; Problems of Achievement Tests in Program Evaluation, Donald Ross Green; Diverse Human Populations and Problems in Educational Program Evaluation via Achievement Testing, Edmund W. Gordon; Critical Issues in Achievement Testing of…

  2. Evaluating Federal Social Programs: An Uncertain Act.

    ERIC Educational Resources Information Center

    Levitan, Sar A.; Wurzburg, Gregory K.

    This study of the federal government's evaluation of social programs indicates that it is virtually impossible to establish a bias-free, valid, and reliable system of inquiry to determine the effects of social programs. Divided into five chapters, the document examines the aspirations and limitations of evaluations, methodology, evaluation in the…

  3. Issues Involved in the Evaluation of Gifted Programmes.

    ERIC Educational Resources Information Center

    Ali, A. Sidiq

    2001-01-01

    This article discusses the purpose of gifted program evaluation and identifies some of the pertinent issues involved in evaluating gifted programs. The gifted program delivered by the Peel District Board of Education in Ontario, Canada, is used to illustrate key evaluation considerations, including gifted identification procedures and gifted…

  4. Improve the Quality of Teaching in Your Schools.

    ERIC Educational Resources Information Center

    Greene, Brenda Z.

    1985-01-01

    Teacher quality can be improved through teacher evaluation, intervention programs, incentives or rewards, and counseling. In the Toledo, Ohio, peer evaluation program, evaluation and staff development go hand in hand. The program was developed through a collaborative and cooperative process and uses teacher consultants to evaluate and supervise…

  5. Program Evaluation: Two Management-Oriented Samples

    ERIC Educational Resources Information Center

    Alford, Kenneth Ray

    2010-01-01

    Two Management-Oriented Samples details two examples of the management-oriented approach to program evaluation. Kenneth Alford, a doctorate candidate at the University of the Cumberlands, details two separate program evaluations conducted in his school district and seeks to compare and contrast the two evaluations based upon the characteristics of…

  6. Evaluation Processes Used to Assess the Effectiveness of Vocational-Technical Programs.

    ERIC Educational Resources Information Center

    Bruhns, Arthur E.

    Evaluation is quantitative or qualitative, the criteria determined by or given to the student. The criteria show how close he has come to the program's objectives and the ranking of individual performance. Vocational education programs susceptible to evaluation are listed and relevant evaluative techniques discussed. Graduate interviews concerning…

  7. The Implementation of Program Evaluation Recommendations in Wisconsin Technical Colleges.

    ERIC Educational Resources Information Center

    Ruhland, Sheila K.

    Implementation of program evaluation recommendations should persuade people that the rewards of an evaluation outweigh the reasons for resistance. A study was undertaken with the following purposes: identify facilitators and barriers to the implementation of program evaluation; determine the proportion of recommendations made in each of the nine…

  8. Practical Considerations in Evaluating Patient/Consumer Health Education Programs.

    ERIC Educational Resources Information Center

    Bryant, Nancy H.

    This report contains brief descriptions of seven evaluative efforts and outcomes of health education programs, some considerations of problems encountered in evaluating the programs, and detailed descriptions of two case studies: (1) a process evaluation of preoperative teaching and (2) a retrospective study of visiting nurse association use by…

  9. Experiential Education and Empowerment Evaluation: Mars Rover Educational Program Case Example.

    ERIC Educational Resources Information Center

    Fetterman, David; Bowman, Cassie

    2002-01-01

    Empowerment evaluation helps people improve their programs using self-evaluation. Empowerment evaluation has three steps: establishing a mission; taking stock of the most significant activities; and planning for the future by establishing goals, strategies, and criteria for evidence. A NASA experiential program for small, distributed groups of…

  10. Program Evaluation in Gifted Education. Essential Readings in Gifted Education Series

    ERIC Educational Resources Information Center

    Callahan, Carolyn M., Ed.; Reis, Sally M., Ed.

    2004-01-01

    The readings in this ready-reference report on specific program evaluations, offer critical guidance in the development and utilization of instruments for assessing gifted and talented programs, and are designed to stimulate the discussion of issues surrounding the evaluation of gifted programs. Key features include: (1) Carolyn M. Callahan's…

  11. A Program Evaluation Tool for Dual Enrollment Transition Programs

    ERIC Educational Resources Information Center

    Grigal, Meg; Dwyre, Amy; Emmett, Joyce; Emmett, Richard

    2012-01-01

    This article describes the development and use of a program evaluation tool designed to support self-assessment of college-based dual enrollment transition programs serving students with intellectual disabilities between the ages of 18-21 in college settings. The authors describe the need for such an evaluation tool, outline the areas addressed by…

  12. EVALUATION OF THE WEIGHT-BASED COLLECTION PROJECT IN FARMINGTON, MINNESOTA: A MITE PROGRAM EVALUATION

    EPA Science Inventory

    This project evaluates a test program of a totally automated weight-based refuse disposal rate system. his test program was conducted by the City of Farmington, Minnesota between 1991 and 1993. he intent of the program was to test a mechanism which would automatically assess a fe...

  13. Applying the Concept of Trustworthiness to the Evaluation of a Clinical Program.

    ERIC Educational Resources Information Center

    Barzansky, Barbara; And Others

    An attending tutor program designed to increase faculty-student contact within an Obstetrics and Gynecology clerkship was evaluated. Sessions were observed, written documents were reviewed, and faculty and students were interviewed in order to determine if the program was meeting its goals. Based on the evaluation data, the program was…

  14. Evaluation of a Community-Based Aging Intervention Program

    ERIC Educational Resources Information Center

    Hsu, Hui-Chuan; Wang, Chun-Hou; Chen, Yi-Chun; Chang, Ming-Chen; Wang, Jean

    2010-01-01

    This study evaluated the outcome and process of a community-based aging intervention program for the elderly in Taiwan. The program included education on nutrition and dietary behavior and on physical activities. Outcome and process evaluations were conducted. The program may have had some effects on decreasing some dietary behavioral problems and…

  15. Assessment and Evaluation of the Utah Master Naturalist Program: Implications for Targeting Audiences

    ERIC Educational Resources Information Center

    Larese-Casanova, Mark

    2011-01-01

    The Utah Master Naturalist Program trains citizens who provide education, outreach, and service to promote citizen stewardship of natural resources within their communities. In 2007-2008, the Watersheds module of the program was evaluated for program success, and participant knowledge was assessed. Assessment and evaluation results indicated that…

  16. Some Measures of Evaluation and Effectiveness in Social Work Practice.

    ERIC Educational Resources Information Center

    Kapoor, J. M.

    Measures of accountability and evaluation of social work program efforts are examined. Evaluation of program effort refers to an assessment of the amount and kinds of program activities considered necessary for the accomplishment of program goals within a particular stage of development. It refers not only to staff time, activity, and commitment,…

  17. Formative Evaluation of the Canada Student Loans Program. Final Report

    ERIC Educational Resources Information Center

    Human Resources and Skills Development Canada, 2004

    2004-01-01

    The "Formative Evaluation of the Canada Student Loans Program" was undertaken to assess issues of program relevance, design and delivery and for the purposes of examining the early impacts of changes made to the program since 1998. The evaluation also reviewed the Performance Measurement Strategy contained in the July 2002 Results-Based…

  18. Evaluation of a Research Mentorship Program in Community Care

    ERIC Educational Resources Information Center

    Ploeg, Jenny; de Witt, Lorna; Hutchison, Brian; Hayward, Lynda; Grayson, Kim

    2008-01-01

    This article describes the results of a qualitative case study evaluating a research mentorship program in community care settings in Ontario, Canada. The purpose of the program was to build evaluation and research capacity among staff of community care agencies through a mentorship program. Data were collected through in-depth, semi-structured…

  19. Evaluation of a federally funded workforce development program: The Centers for Public Health Preparedness☆

    PubMed Central

    Sobelson, Robyn K.; Young, Andrea C.

    2017-01-01

    The Centers for Public Health Preparedness (CPHP) program was a five-year cooperative agreement funded by the Centers for Disease Control and Prevention (CDC). The program was initiated in 2004 to strengthen terrorism and emergency preparedness by linking academic expertise to state and local health agency needs. The purposes of the evaluation study were to identify the results achieved by the Centers and inform program planning for future programs. The evaluation was summative and retrospective in its design and focused on the aggregate outcomes of the CPHP program. The evaluation results indicated progress was achieved on program goals related to development of new training products, training members of the public health workforce, and expansion of partnerships between accredited schools of public health and state and local public health departments. Evaluation results, as well as methodological insights gleaned during the planning and conduct of the CPHP evaluation, were used to inform the design of the next iteration of the CPHP Program, the Preparedness and Emergency Response Learning Centers (PERLC). PMID:23380597

  20. Collaborative Evaluation within a Framework of Stakeholder-Oriented Evaluation Approaches

    ERIC Educational Resources Information Center

    O'Sullivan, Rita G.

    2012-01-01

    Collaborative Evaluation systematically invites and engages stakeholders in program evaluation planning and implementation. Unlike "distanced" evaluation approaches, which reject stakeholder participation as evaluation team members, Collaborative Evaluation assumes that active, on-going engagement between evaluators and program staff,…

  1. Assessing the effects of employee assistance programs: a review of employee assistance program evaluations.

    PubMed

    Colantonio, A

    1989-01-01

    Employee assistance programs have grown at a dramatic rate, yet the effectiveness of these programs has been called into question. The purpose of this paper was to assess the effectiveness of employee assistance programs (EAPs) by reviewing recently published EAP evaluations. All studies evaluating EAPs published since 1975 from peer-reviewed journals in the English language were included in this analysis. Each of the articles was assessed in the following areas: (a) program description (subjects, setting, type of intervention, format), (b) evaluation design (research design, variables measured, operational methods), and (c) program outcomes. Results indicate numerous methodological and conceptual weaknesses and issues. These weaknesses included lack of controlled research designs and short time lags between pre- and post-test measures. Other problems identified are missing information regarding subjects, type of intervention, how variables are measured (operational methods), and reliability and validity of evaluation instruments. Due to the aforementioned weaknesses, positive outcomes could not be supported. Recommendations are made for future EAP evaluations.

  2. Assessing the effects of employee assistance programs: a review of employee assistance program evaluations.

    PubMed Central

    Colantonio, A.

    1989-01-01

    Employee assistance programs have grown at a dramatic rate, yet the effectiveness of these programs has been called into question. The purpose of this paper was to assess the effectiveness of employee assistance programs (EAPs) by reviewing recently published EAP evaluations. All studies evaluating EAPs published since 1975 from peer-reviewed journals in the English language were included in this analysis. Each of the articles was assessed in the following areas: (a) program description (subjects, setting, type of intervention, format), (b) evaluation design (research design, variables measured, operational methods), and (c) program outcomes. Results indicate numerous methodological and conceptual weaknesses and issues. These weaknesses included lack of controlled research designs and short time lags between pre- and post-test measures. Other problems identified are missing information regarding subjects, type of intervention, how variables are measured (operational methods), and reliability and validity of evaluation instruments. Due to the aforementioned weaknesses, positive outcomes could not be supported. Recommendations are made for future EAP evaluations. PMID:2728498

  3. Evaluative Thinking in Practice: The National Asthma Control Program.

    PubMed

    Fierro, Leslie A; Codd, Heather; Gill, Sarah; Pham, Phung K; Grandjean Targos, Piper T; Wilce, Maureen

    2018-01-01

    Although evaluative thinking lies at the heart of what we do as evaluators and what we hope to promote in others through our efforts to build evaluation capacity, researchers have given limited attention to measuring this concept. We undertook a research study to better understand how instances of evaluative thinking may present in practice-based settings-specifically within four state asthma control programs funded by the Centers for Disease Control and Prevention's National Asthma Control Program. Through content analyses of documents as well as interviews and a subsequent focus group with four state asthma control programs' evaluators and program managers we identified and defined twenty-two indicators of evaluative thinking. Findings provide insights about what practitioners may wish to look for when they intend to build evaluative thinking and the types of data sources that may be more or less helpful in such efforts.

  4. Do State Pre-K Programs Improve Children's Pre-Literacy and Math Learning? Evaluation Science Brief

    ERIC Educational Resources Information Center

    National Forum on Early Childhood Program Evaluation, 2008

    2008-01-01

    "Evaluation Science Briefs" summarize the findings and implications of a recent study evaluating the effects of an early childhood program or environment. This Brief evaluates the study "An Effectiveness-Based Evaluation of Five State Pre-Kindergarten Programs" (V. C. Wong, T. D. Cook, W. S. Barnett, and K. Jung.) States have high aspirations for…

  5. Toward building a typology for the evaluation of services in family support programs.

    PubMed

    Manalo, V; Meezan, W

    2000-01-01

    This article briefly reviews the history, philosophy, practice principles, and foci of family support programs, examines the typologies currently in use to classify these programs, and discusses the difficulties these classifications pose for program evaluators. The authors introduce a new typology that deconstructs family support programs into their component services and discuss the potential of this typology for evaluation of family support services.

  6. Program evaluation of FHWA pedestrian and bicycle safety activities.

    DOT National Transportation Integrated Search

    2011-03-01

    "Introduction : FHWAs Office of Highway Safety (HSA) initiated a program evaluation by Booz Allen Hamilton to assess the overall effectiveness of the Agencys Pedestrian and Bicycle Safety Program. The evaluation covers pedestrian and bicycle sa...

  7. Second NBL measurement evaluation program meeting: A summary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spaletto, M.I.; Clapper, M.; Tolbert, M.E.M.

    New Brunswick Laboratory (NBL), the US government`s nuclear materials measurements and reference materials laboratory, administers interlaboratory measurement evaluation programs to evaluate the quality and adequacy of safeguards measurements. The NBL Measurement Evaluation Program covers several types of safeguards analytical measurements. The Safeguards Measurement Evaluation (SME) program distributes test materials destructive measurements of uranium for both elemental concentration and isotopic abundances, and of plutonium for isotopic abundances. The Calorimetry Exchange (CalEx) Program tests the quality of nondestructive measurements of plutonium isotopic abundances by gamma spectroscopy and plutonium concentration by calorimetry. In May 1997, more than 30 representatives from the Department ofmore » Energy (DOE), its contractor laboratories, and Nuclear Regulatory Commission licensees met at NBL in Argonne, Illinois, for the annual meeting of the Measurement Evaluation Program. The summary which follows details key points that were discussed or presented at the meeting.« less

  8. Using program evaluation to support knowledge translation in an interprofessional primary care team: a case study.

    PubMed

    Donnelly, Catherine; Shulha, Lyn; Klinger, Don; Letts, Lori

    2016-10-06

    Evaluation is a fundamental component in building quality primary care and is ideally situated to support individual, team and organizational learning by offering an accessible form of participatory inquiry. The evaluation literature has begun to recognize the unique features of KT evaluations and has described attributes to consider when evaluating KT activities. While both disciplines have focused on the evaluation of KT activities neither has explored the role of evaluation in KT. The purpose of the paper is to examine how participation in program evaluation can support KT in a primary care setting. A mixed methods case study design was used, where evaluation was conceptualized as a change process and intervention. A Memory Clinic at an interprofessional primary care clinic was the setting in which the study was conducted. An evaluation framework, Pathways of Influence provided the theoretical foundation to understand how program evaluation can facilitate the translation of knowledge at the level of the individual, inter-personal (Memory Clinic team) and the organization. Data collection included questionnaires, interviews, evaluation log and document analysis. Questionnaires and interviews were administered both before and after the evaluation: Pattern matching was used to analyze the data based on predetermined propositions. Individuals gained program knowledge that resulted in changes to both individual and program practices. One of the key themes was the importance clinicians placed on local, program based knowledge. The evaluation had less influence on the broader health organization. Program evaluation facilitated individual, team and organizational learning. The use of evaluation to support KT is ideally suited to a primary care setting by offering relevant and applicable knowledge to primary care team members while being sensitive to local context.

  9. Methods for evaluating a mature substance abuse prevention/early intervention program.

    PubMed

    Becker, L R; Hall, M; Fisher, D A; Miller, T R

    2000-05-01

    The authors describe methods for work in progress to evaluate four workplace prevention and/or early intervention programs designed to change occupational norms and reduce substance abuse at a major U.S. transportation company. The four programs are an employee assistance program, random drug testing, managed behavioral health care, and a peer-led intervention program. An elaborate mixed-methods evaluation combines data collection and analysis techniques from several traditions. A process-improvement evaluation focuses on the peer-led component to describe its evolution, document the implementation process for those interested in replicating it, and provide information for program improvement. An outcome-assessment evaluation examines impacts of the four programs on job performance measures (e.g., absenteeism, turnover, injury, and disability rates) and includes a cost-offset and employer cost-savings analysis. Issues related to using archival data, combining qualitative and quantitative designs, and working in a corporate environment are discussed.

  10. Using Art For Health Promotion: Evaluating an In-School Program Through Student Perspectives.

    PubMed

    McKay, Fiona H; McKenzie, Hayley

    2017-09-01

    The value of incorporating arts-based approaches into health promotion programs has long been recognized as useful in affecting change. Such approaches have been used in many schools across Australia and have been found to promote general well-being and mental health. Despite these positive findings, few programs have used or evaluated an integrated arts-based approach to achieve health and well-being goals. This article presents the findings of an evaluation of an integrated arts-based program focused on creativity and improving well-being in students. The findings of this evaluation suggest that students who took part in the program were more interested in art and music at the end of the program and had gained an overall increase in awareness and mindfulness and a positivity toward leisure activities. This evaluation provides some evidence to suggest that this type of program is a promising way to promote well-being in schools.

  11. Evaluation of a Demonstration Program for Postsecondary Hospitality Education.

    ERIC Educational Resources Information Center

    Weis, Susan F.

    A three-phase program evaluation effort employing comparison groups and a pre-post test design indicate formative guidelines for programs revision and summative results indicative of the effectiveness of a demonstration associate degree program for hospitality education. Program effectiveness is defined in terms of the program's enrollment of…

  12. Process Evaluation for a Prison-based Substance Abuse Program.

    ERIC Educational Resources Information Center

    Staton, Michele; Leukefeld, Carl; Logan, T. K.; Purvis, Rick

    2000-01-01

    Presents findings from a process evaluation conducted in a prison-based substance abuse program in Kentucky. Discusses key components in the program, including a detailed program description, modifications in planned treatment strategies, program documentation, and perspectives of staff and clients. Findings suggest that prison-based programs have…

  13. Evaluation of a Postdischarge Call System Using the Logic Model.

    PubMed

    Frye, Timothy C; Poe, Terri L; Wilson, Marisa L; Milligan, Gary

    2018-02-01

    This mixed-method study was conducted to evaluate a postdischarge call program for congestive heart failure patients at a major teaching hospital in the southeastern United States. The program was implemented based on the premise that it would improve patient outcomes and overall quality of life, but it had never been evaluated for effectiveness. The Logic Model was used to evaluate the input of key staff members to determine whether the outputs and results of the program matched the expectations of the organization. Interviews, online surveys, reviews of existing patient outcome data, and reviews of publicly available program marketing materials were used to ascertain current program output. After analyzing both qualitative and quantitative data from the evaluation, recommendations were made to the organization to improve the effectiveness of the program.

  14. An Evaluation System for the Online Training Programs in Meteorology and Hydrology

    ERIC Educational Resources Information Center

    Wang, Yong; Zhi, Xiefei

    2009-01-01

    This paper studies the current evaluation system for the online training program in meteorology and hydrology. CIPP model that includes context evaluation, input evaluation, process evaluation and product evaluation differs from Kirkpatrick model including reactions evaluation, learning evaluation, transfer evaluation and results evaluation in…

  15. Iterative evaluation in a mobile counseling and testing program to reach people of color at risk for HIV--new strategies improve program acceptability, effectiveness, and evaluation capabilities.

    PubMed

    Spielberg, Freya; Kurth, Ann; Reidy, William; McKnight, Teka; Dikobe, Wame; Wilson, Charles

    2011-06-01

    This article highlights findings from an evaluation that explored the impact of mobile versus clinic-based testing, rapid versus central-lab based testing, incentives for testing, and the use of a computer counseling program to guide counseling and automate evaluation in a mobile program reaching people of color at risk for HIV. The program's results show that an increased focus on mobile outreach using rapid testing, incentives and health information technology tools may improve program acceptability, quality, productivity and timeliness of reports. This article describes program design decisions based on continuous quality assessment efforts. It also examines the impact of the Computer Assessment and Risk Reduction Education computer tool on HIV testing rates, staff perception of counseling quality, program productivity, and on the timeliness of evaluation reports. The article concludes with a discussion of implications for programmatic responses to the Centers for Disease Control and Prevention's HIV testing recommendations.

  16. Evaluating Continuing Education Needs and Program Effectiveness Using a Survey of Virginia's SHARP Logger Program Participants

    ERIC Educational Resources Information Center

    Barrett, Scott M.; Bolding, M. Chad; Munsell, John F.

    2012-01-01

    Virginia's SHARP logger program is a Cooperative Extension program currently providing training to over 1,500 loggers, foresters, and others. We conducted a mail survey of SHARP loggers to characterize program participants, assess programming needs, and evaluate program effectiveness. Results indicate a diverse group of participants in terms of…

  17. Evaluating an English Language Teacher Education Program through Peacock's Model

    ERIC Educational Resources Information Center

    Coskun, Abdullah; Daloglu, Aysegul

    2010-01-01

    The main aim of this study is to draw attention to the importance of program evaluation for teacher education programs and to reveal the pre-service English teacher education program components that are in need of improvement or maintenance both from teachers' and students' perspectives by using Peacock's (2009) recent evaluation model in a…

  18. Using a Crystal Ball Instead of a Rear-View Mirror: Helping State Legislators Assess the Future Impacts of Major Federal Legislation

    ERIC Educational Resources Information Center

    Alter, Joel; Patterson, John

    2006-01-01

    Typically, program evaluation agencies in the legislative branch of state government examine programs that have already been implemented. These evaluations often consider whether a program achieved the legislature's original goals or complied with statutory requirements. Program evaluations frequently determine whether executive branch agencies…

  19. Participants' perceptions of the 1997-1998 Missouri State Parks Passport Program

    Treesearch

    Yi-Jin Ye; Jaclyn Card

    2002-01-01

    Service quality is increasingly important to park managers. Recreation and park evaluation measures the implementation and outcome of programs for decision-making. Decisions based on evaluations are often concerned with improving the quality of the program for participants. The purpose of the study was to evaluate the Missouri State Parks Passport Program (MSPPP) by...

  20. Evaluation of Turkish Education Programs

    ERIC Educational Resources Information Center

    Durmuscelebi, Mustafa

    2010-01-01

    The aim of this study is to evaluate the new Turkish education program that has been being implemented since 2005 gradually in light of teacher suggestions. The study has been done in scanning model. In this study which has been conducted with the purpose of evaluating the newly prepared Turkish education programs, the program has been tried to be…

  1. An Evaluation of On-Line, Interactive Tutorials Designed to Teach Practice Concepts

    ERIC Educational Resources Information Center

    Seabury, Brett A.

    2005-01-01

    This paper presents an evaluation of two on-line-based programs designed to teach practice skills. One program teaches crisis intervention and the other teaches suicide assessment. The evaluation of the use of these programs compares outcomes for two groups of students, one using the interactive program outside a class context and the other using…

  2. Evaluation of Selected New York City Umbrella Programs, 1974-1975 School Year.

    ERIC Educational Resources Information Center

    Fordham Univ., Bronx, NY. Inst. for Research and Evaluation.

    An evaluation of twelve different New York City Umbrella Programs coordinated in New York City public schools during the 1974-1975 school year is contained in this document. This report presents a description and evaluation of these programs, together with the major findings. The programs were implemented in the following areas: (1) tutoring in…

  3. Implementing and Evaluating a Rural Community-Based Sexual Abstinence Program: Challenges and Solutions

    ERIC Educational Resources Information Center

    Stauss, Kimberly; Boyas, Javier; Murphy-Erby, Yvette

    2012-01-01

    Informing both program evaluation and practice research, this paper describes lessons learned during the planning, implementation, and pilot phases of an abstinence education program based in a rural community in a southern state in the USA. Although a number of challenges can emerge in successfully implementing and evaluating such a program in a…

  4. 45 CFR 2516.840 - By what standards will the Corporation evaluate individual Learn and Serve America programs?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false By what standards will the Corporation evaluate individual Learn and Serve America programs? 2516.840 Section 2516.840 Public Welfare Regulations Relating to... Learn and Serve America programs? The Corporation will evaluate programs based on the following: (a) The...

  5. 45 CFR 2516.840 - By what standards will the Corporation evaluate individual Learn and Serve America programs?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false By what standards will the Corporation evaluate individual Learn and Serve America programs? 2516.840 Section 2516.840 Public Welfare Regulations Relating to... Learn and Serve America programs? The Corporation will evaluate programs based on the following: (a) The...

  6. 45 CFR 2516.840 - By what standards will the Corporation evaluate individual Learn and Serve America programs?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 4 2013-10-01 2013-10-01 false By what standards will the Corporation evaluate individual Learn and Serve America programs? 2516.840 Section 2516.840 Public Welfare Regulations Relating to... Learn and Serve America programs? The Corporation will evaluate programs based on the following: (a) The...

  7. 45 CFR 2516.840 - By what standards will the Corporation evaluate individual Learn and Serve America programs?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false By what standards will the Corporation evaluate individual Learn and Serve America programs? 2516.840 Section 2516.840 Public Welfare Regulations Relating to... Learn and Serve America programs? The Corporation will evaluate programs based on the following: (a) The...

  8. From Schools to Community Learning Centers: A Program Evaluation of a School Reform Process

    ERIC Educational Resources Information Center

    Magolda, Peter; Ebben, Kelsey

    2007-01-01

    This manuscript reports on a program evaluation of a school reform initiative conducted in an Ohio city. The paper describes, interprets, and evaluates this reform process aimed at transforming schools into community learning centers. The manuscript also describes and analyzes the initiative's program evaluation process. Elliot Eisner's [(1998).…

  9. Evaluating public participation in environmental decision-making: EPA's superfund community involvement program.

    Treesearch

    Susan Charnley; Bruce Engelbert

    2005-01-01

    This article discusses an 8-year, ongoing project that evaluates the Environmental Protection Agency's Superfund community involvement program. The project originated as a response to the Government Performance and Results Act, which requires federal agencies to articulate program goals, and evaluate and report their progress in meeting those goals. The evaluation...

  10. Formative Evaluation in a Cognitive Developmental Program for Young Children.

    ERIC Educational Resources Information Center

    Willis, Sherry L.; And Others

    The Cognitive Developmental Early Childhood program at Pennsylvania State University has formulated a program, curriculum, and evaluation system guided by Piagetian theory. The evaluation system described in this paper is a result of an intensive examination of the purposes and types of evaluation systems for their compatibility with the Piagetian…

  11. The Do's and Don'ts in Regard to the Evaluation of Bilingual Programs.

    ERIC Educational Resources Information Center

    Rodriquez-Brown, Flora V.

    The difficulties in evaluating bilingual education appear to have prevented success in all but a few evaluation attempts, but better and more meaningful evaluation is neccessary in order to identify the strengths and weaknesses of bilingual programs. Many bilingual programs are undergoing constant modification, adequate assessment instruments have…

  12. Evaluating Federal Social Programs: Finding out What Works and What Does Not

    ERIC Educational Resources Information Center

    Muhlhausen, David B.

    2012-01-01

    Federal social programs are rarely evaluated to determine whether they are actually accomplishing their intended purposes. As part of its obligation to spend taxpayers' dollars wisely, Congress should mandate that experimental evaluations of every federal social program be conducted. The evaluations should be large-scale, multisite studies to…

  13. What Have We Learned about the Politics of Program Evaluation?

    ERIC Educational Resources Information Center

    Chelimsky, Eleanor

    The politics of program evaluation are discussed from the personal perspective of the Director of the General Accounting Office's Program Evaluation and Methodology Division, which has produced reports for committees of the United States Congress. It is concluded that successful evaluations must be useful to others and must understand the…

  14. Adapting the Empowerment Evaluation Model: A Mental Health Drop-In Center Case Example

    ERIC Educational Resources Information Center

    Sullins, Carolyn D.

    2003-01-01

    Empowerment evaluation involves a program's stakeholders in designing and implementing an evaluation of their own program, thus contributing to the program's improvement and self-determination (Fetterman, 1994, 1996). It appeared to be an appropriate approach for evaluating a mental health drop-in center, which had congruent goals of collaboration…

  15. Formative Evaluation of the Adult Learning, Literacy and Essential Skills Program. Final Report

    ERIC Educational Resources Information Center

    Human Resources and Skills Development Canada, 2010

    2010-01-01

    This report presents the results of the formative evaluation of the Adult Learning, Literacy and Essential Skills Program (ALLESP). Data collection related to this evaluation took place between November 2008 and May 2009. The evaluation resulted in the following four recommendations: (1) It is recommended that Program objectives and activities…

  16. Development and application of course-embedded assessment system for program outcome evaluation in the Korean nursing education: A pilot study.

    PubMed

    Park, Jee Won; Seo, Eun Ji; You, Mi-Ae; Song, Ju-Eun

    2016-03-01

    Program outcome evaluation is important because it is an indicator for good quality of education. Course-embedded assessment is one of the program outcome evaluation methods. However, it is rarely used in Korean nursing education. The study purpose was to develop and apply preliminarily a course-embedded assessment system to evaluate one program outcome and to share our experiences. This was a methodological study to develop and apply the course-embedded assessment system based on the theoretical framework in one nursing program in South Korea. Scores for 77 students generated from the three practicum courses were used. The course-embedded assessment system was developed following the six steps suggested by Han's model as follows. 1) One program outcome in the undergraduate program, "nursing process application ability", was selected and 2) the three clinical practicum courses related to the selected program outcome were identified. 3) Evaluation tools including rubric and items were selected for outcome measurement and 4) performance criterion, the educational goal level for the program, was established. 5) Program outcome was actually evaluated using the rubric and evaluation items in the three practicum courses and 6) the obtained scores were analyzed to identify the achievement rate, which was compared with the performance criterion. Achievement rates for the selected program outcome in adult, maternity, and pediatric nursing practicum were 98.7%, 100%, and 66.2% in the case report and 100% for all three in the clinical practice, and 100%, 100%, and 87% respectively for the conference. These are considered as satisfactory levels when compared with the performance criterion of "at least 60% or more". Course-embedded assessment can be used as an effective and economic method to evaluate the program outcome without running an integrative course additionally. Further studies to develop course-embedded assessment systems for other program outcomes in nursing education are needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM TECHNOLOGY PROFILES: SIXTH EDITION

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) Program evaluates new and promising treatment and monitoring and measurement technologies for cleanup of hazardous waste sites. The program was created to encourage the development and routine use of innovative treatment techn...

  18. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM - TECHNOLOGY PROFILES - SEVENTH EDITION

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) Program evaluates new and promising treatment and monitoring and measurement technologies for cleanup of hazardous waste sites. The program was created to encourage the development and routine use of innovative treatment techn...

  19. Development of a Spring-Loaded Impact Device to Deliver Injurious Mechanical Impacts to the Articular Cartilage Surface

    PubMed Central

    Alexander, Peter G.; Song, Yingjie; Taboas, Juan M.; Chen, Faye H.; Melvin, Gary M.; Manner, Paul A.

    2013-01-01

    Objective: Traumatic impacts on the articular joint surface in vitro are known to lead to degeneration of the cartilage. The main objective of this study was to develop a spring-loaded impact device that can be used to deliver traumatic impacts of consistent magnitude and rate and to find whether impacts cause catabolic activities in articular cartilage consistent with other previously reported impact models and correlated with the development of osteoarthritic lesions. In developing the spring-loaded impactor, the operating hypothesis is that a single supraphysiologic impact to articular cartilage in vitro can affect cartilage integrity, cell viability, sulfated glycosaminoglycan and inflammatory mediator release in a dose-dependent manner. Design: Impacts of increasing force are delivered to adult bovine articular cartilage explants in confined compression. Impact parameters are correlated with tissue damage, cell viability, matrix and inflammatory mediator release, and gene expression 24 hours postimpact. Results: Nitric oxide release is first detected after 7.7 MPa impacts, whereas cell death, glycosaminoglycan release, and prostaglandin E2 release are first detected at 17 MPa. Catabolic markers increase linearly to maximal levels after ≥36 MPa impacts. Conclusions: A single supraphysiologic impact negatively affects cartilage integrity, cell viability, and GAG release in a dose-dependent manner. Our findings showed that 7 to 17 MPa impacts can induce cell death and catabolism without compromising the articular surface, whereas a 17 MPa impact is sufficient to induce increases in most common catabolic markers of osteoarthritic degeneration. PMID:26069650

  20. Anatomical manifestations of primary blast ocular trauma observed in a postmortem porcine model.

    PubMed

    Sherwood, Daniel; Sponsel, William E; Lund, Brian J; Gray, Walt; Watson, Richard; Groth, Sylvia L; Thoe, Kimberly; Glickman, Randolph D; Reilly, Matthew A

    2014-02-24

    We qualitatively describe the anatomic features of primary blast ocular injury observed using a postmortem porcine eye model. Porcine eyes were exposed to various levels of blast energy to determine the optimal conditions for future testing. We studied 53 enucleated porcine eyes: 13 controls and 40 exposed to a range of primary blast energy levels. Eyes were preassessed with B-scan and ultrasound biomicroscopy (UBM) ultrasonography, photographed, mounted in gelatin within acrylic orbits, and monitored with high-speed videography during blast-tube impulse exposure. Postimpact photography, ultrasonography, and histopathology were performed, and ocular damage was assessed. Evidence for primary blast injury was obtained. While some of the same damage was observed in the control eyes, the incidence and severity of this damage in exposed eyes increased with impulse and peak pressure, suggesting that primary blast exacerbated these injuries. Common findings included angle recession, internal scleral delamination, cyclodialysis, peripheral chorioretinal detachments, and radial peripapillary retinal detachments. No full-thickness openings of the eyewall were observed in any of the eyes tested. Scleral damage demonstrated the strongest associative tendency for increasing likelihood of injury with increased overpressure. These data provide evidence that primary blast alone (in the absence of particle impact) can produce clinically relevant ocular damage in a postmortem model. The blast parameters derived from this study are being used currently in an in vivo model. We also propose a new Cumulative Injury Score indicating the clinical relevance of observed injuries.

  1. Mathematical model for studying cyclist kinematics in vehicle-bicycle frontal collisions

    NASA Astrophysics Data System (ADS)

    Condrea, OA; Chiru, A.; Chiriac, RL; Vlase, S.

    2017-10-01

    For the development of effective vehicle related safety solutions to improve cyclist protection, kinematic predictions are essential. The objective of the paper was the elaboration of a simple mathematical model for predicting cyclist kinematics, with the advantage of yielding simple results for relatively complicated impact situations. Thus, the use of elaborated math software is not required and the calculation time is shortened. The paper presents a modelling framework to determine cyclist kinematic behaviour for the situations in which a M1 category vehicle frontally hits the rear part of a bicycle. After the primary impact between the vehicle front bumper and the bicycle, the cyclist hits the vehicle’s bonnet, the windscreen or both the vehicle’s bonnet and the windscreen in short succession. The head-windshield impact is often the most severe impact, causing serious and potentially lethal injuries. The cyclist is represented by a rigid segment and the equations of motion for the cyclist after the primary impact are obtained by applying Newton’s second law of motion. The impact time for the contact between the vehicle and the cyclist is yielded afterwards by formulating and intersecting the trajectories for two points positioned on the cyclist’s head/body and the vehicle’s windscreen/bonnet while assuming that the cyclist’s equations of motion after the primary impact remain the same. Postimpact kinematics for the secondary impact are yielded by applying linear and angular momentum conservation laws.

  2. Imaging the Chicxulub central crater zone from large scale seismic acoustic wave propagation and gravity modeling

    NASA Astrophysics Data System (ADS)

    Fucugauchi, J. U.; Ortiz-Aleman, C.; Martin, R.

    2017-12-01

    Large complex craters are characterized by central uplifts that represent large-scale differential movement of deep basement from the transient cavity. Here we investigate the central sector of the large multiring Chicxulub crater, which has been surveyed by an array of marine, aerial and land-borne geophysical methods. Despite high contrasts in physical properties,contrasting results for the central uplift have been obtained, with seismic reflection surveys showing lack of resolution in the central zone. We develop an integrated seismic and gravity model for the main structural elements, imaging the central basement uplift and melt and breccia units. The 3-D velocity model built from interpolation of seismic data is validated using perfectly matched layer seismic acoustic wave propagation modeling, optimized at grazing incidence using shift in the frequency domain. Modeling shows significant lack of illumination in the central sector, masking presence of the central uplift. Seismic energy remains trapped in an upper low velocity zone corresponding to the sedimentary infill, melt/breccias and surrounding faulted blocks. After conversion of seismic velocities into a volume of density values, we use massive parallel forward gravity modeling to constrain the size and shape of the central uplift that lies at 4.5 km depth, providing a high-resolution image of crater structure.The Bouguer anomaly and gravity response of modeled units show asymmetries, corresponding to the crater structure and distribution of post-impact carbonates, breccias, melt and target sediments

  3. Anatomy of the Chesapeake Bay impact structure revealed by seismic imaging, Delmarva Peninsula, Virginia, USA

    USGS Publications Warehouse

    Catchings, R.D.; Powars, D.S.; Gohn, G.S.; Horton, J. Wright; Goldman, M.R.; Hole, J.A.

    2008-01-01

    A 30-km-long, radial seismic reflection and refraction survey completed across the northern part of the late Eocene Chesapeake Bay impact structure (CBIS) on the Delmarva Peninsula, Virginia, USA, confirms that the CBIS is a complex central-peak crater. We used a tomographic P wave velocity model and low-fold reflection images, constrained by data from two deep boreholes located on the profile, to interpret the structure and composition of the upper 5 km of crust. The seismic images exhibit well-defined structural features, including (with increasing radial distance) a collapsed central uplift, a breccia-filled moat, and a collapsed transient-crater margin (which collectively constitute a ???40-km-wide collapsed transient crater), and a shallowly deformed annular trough. These seismic images are the first to resolve the deep structure of the crater (>1 km) and the boundaries between the central uplift, moat, and annular trough. Several distinct seismic signatures distinguish breccia units from each other and from more coherent crystalline rocks below the central uplift, moat, and annular trough. Within the moat, breccia extends to a minimum depth of 1.5 km or a maximum of 3.5 km, depending upon the interpretation of the deepest layered materials. The images show ???350 to 500 m of postimpact sediments above the impactites. The imaged structure of the CBIS indicates a complex sequence of event during the cratering process that will provide new constraints for numerical modeling. Copyright 2008 by the American Geophysical Union.

  4. Surface expression of the Chicxulub crater

    PubMed

    Pope, K O; Ocampo, A C; Kinsland, G L; Smith, R

    1996-06-01

    Analyses of geomorphic, soil, and topographic data from the northern Yucatan Peninsula, Mexico, confirm that the buried Chicxulub impact crater has a distinct surface expression and that carbonate sedimentation throughout the Cenozoic has been influenced by the crater. Late Tertiary sedimentation was mostly restricted to the region within the buried crater, and a semicircular moat existed until at least Pliocene time. The topographic expression of the crater is a series of features concentric with the crater. The most prominent is an approximately 83-km-radius trough or moat containing sinkholes (the Cenote ring). Early Tertiary surfaces rise abruptly outside the moat and form a stepped topography with an outer trough and ridge crest at radii of approximately 103 and approximately 129 km, respectively. Two discontinuous troughs lie within the moat at radii of approximately 41 and approximately 62 km. The low ridge between the inner troughs corresponds to the buried peak ring. The moat corresponds to the outer edge of the crater floor demarcated by a major ring fault. The outer trough and the approximately 62-km-radius inner trough also mark buried ring faults. The ridge crest corresponds to the topographic rim of the crater as modified by postimpact processes. These interpretations support previous findings that the principal impact basin has a diameter of approximately 180 km, but concentric, low-relief slumping extends well beyond this diameter and the eroded crater rim may extend to a diameter of approximately 260 km.

  5. Association of anatase (TiO2) and microbes: Unusual fossilization effect or a potential biosignature?

    USGS Publications Warehouse

    Glamoclija, M.; Steele, A.; Fries, M.; Schieber, J.; Voytek, M.A.; Cockell, C.S.

    2009-01-01

    We combined microbial paleontology and molecular biology methods to study the Eyreville B drill core from the 35.3-Ma-old Chesapeake Bay impact structure, Virginia, USA. The investigated sample is a pyrite vein collected from the 1353.81- 1353.89 m depth interval, located within a section of biotite granite. The granite is a pre-impact rock that was disrupted by the impact event. A search for inorganic (mineral) biosignatures revealed the presence of micron-size rod morphologies of anatase (TiO2) embedded in chlorite coatings on pyrite grains. Neither the Acridine Orange microbial probe nor deoxyribonucleic acid (DNA) extraction followed by polymerase chain reaction (PCR) amplifi cation showed the presence of DNA or ribonucleic acid (RNA) at the location of anatase rods, implying the absence of viable cells in the investigated area. A Nile Red microbial probe revealed the presence of lipids in the rods. Because most of the lipids are resistant over geologic time spans, they are good biomarkers, and they are an indicator of biogenicity for these possibly 35-Ma-old microbial fossils. The mineral assemblage suggests that rod morphologies are associated with low-temperature (<100 ??C) hydrothermal alteration that involved aqueous fluids. The temporal constraints on the anatase fossils are still uncertain because pre-impact alteration of the granite and postimpact heating may have provided identical conditions for anatase precipitation and microbial preservation. ?? 2009 The Geological Society of America.

  6. Buildings vs. ballistics: Quantifying the vulnerability of buildings to volcanic ballistic impacts using field studies and pneumatic cannon experiments

    NASA Astrophysics Data System (ADS)

    Williams, G. T.; Kennedy, B. M.; Wilson, T. M.; Fitzgerald, R. H.; Tsunematsu, K.; Teissier, A.

    2017-09-01

    Recent casualties in volcanic eruptions due to trauma from blocks and bombs necessitate more rigorous, ballistic specific risk assessment. Quantitative assessments are limited by a lack of experimental and field data on the vulnerability of buildings to ballistic hazards. An improved, quantitative understanding of building vulnerability to ballistic impacts is required for informing appropriate life safety actions and other risk reduction strategies. We assessed ballistic impacts to buildings from eruptions at Usu Volcano and Mt. Ontake in Japan and compiled available impact data from eruptions elsewhere to identify common damage patterns from ballistic impacts to buildings. We additionally completed a series of cannon experiments which simulate ballistic block impacts to building claddings to investigate their performance over a range of ballistic projectile velocities, masses and energies. Our experiments provide new insights by quantifying (1) the hazard associated with post-impact shrapnel from building and rock fragments; (2) the effect of impact obliquity on damage; and (3) the additional impact resistance buildings possess when claddings are struck in areas directly supported by framing components. This was not well identified in previous work which may have underestimated building vulnerability to ballistic hazards. To improve assessment of building vulnerability to ballistics, we use our experimental and field data to develop quantitative vulnerability models known as fragility functions. Our fragility functions and field studies show that although unreinforced buildings are highly vulnerable to large ballistics (> 20 cm diameter), they can still provide shelter, preventing death during eruptions.

  7. Nucleobase and amino acid formation through impacts of meteorites on the early ocean

    NASA Astrophysics Data System (ADS)

    Furukawa, Yoshihiro; Nakazawa, Hiromoto; Sekine, Toshimori; Kobayashi, Takamichi; Kakegawa, Takeshi

    2015-11-01

    The emergence of life's building blocks on the prebiotic Earth was the first crucial step for the origins of life. Extraterrestrial delivery of intact amino acids and nucleobases is the prevailing hypothesis for their availability on prebiotic Earth because of the difficulties associated with the production of these organics from terrestrial carbon and nitrogen sources under plausible prebiotic conditions. However, the variety and amounts of these intact organics delivered by meteorites would have been limited. Previous shock-recovery experiments have demonstrated that meteorite impact reactions could have generated organics on the prebiotic Earth. Here, we report on the simultaneous formation of nucleobases (cytosine and uracil) found in DNA and/or RNA, various proteinogenic amino acids (glycine, alanine, serine, aspartic acid, glutamic acid, valine, leucine, isoleucine, and proline), non-proteinogenic amino acids, and aliphatic amines in experiments simulating reactions induced by extraterrestrial objects impacting on the early oceans. To the best of our knowledge, this is the first report of the formation of nucleobases from inorganic materials by shock conditions. In these experiments, bicarbonate was used as the carbon source. Bicarbonate, which is a common dissolved carbon species in CO2-rich atmospheric conditions, was presumably the most abundant carbon species in the early oceans and in post-impact plumes. Thus, the present results expand the possibility that impact-induced reactions generated various building blocks for life on prebiotic Earth in large quantities through the use of terrestrial carbon reservoirs.

  8. Momentum and Angular Momentum Transfer in Oblique Impacts: Implications for Asteroid Rotations

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Masahisa; Hasegawa, Sunao; Shirogane, Nobutoshi

    1996-09-01

    We conducted a series of high velocity oblique impact experiments (0.66-6.7 km/s) using polycarbonate (plastic) projectiles and targets made of mortar, aluminum alloy, and mild steel. We then calculated the efficiencies of momentum transfer for small cratering impacts. They are η = (M‧Vn‧)/(mvn) and ζ = (M‧Vt‧)/(mvt), wheremandvare the mass and velocity of a projectile, andM‧ andV‧ represent those of a postimpact target. Subscripts “n” and “t” denote the components normal and tangential to the target surface at the impact point, respectively. The main findings are: (1) η increases with increasing impact velocity; (2) η is larger for mortar than for ductile metallic targets; (3) ζ for mortar targets seems to increase with the impact velocity in the velocity range less than about 2 km/s and decrease with it in the higher velocity range; (4) ζ for the aluminum alloy targets correlates negatively with incident zenith angle of the projectile. In addition to these findings on the momentum transfer, we show theoretically that “ζL” can be expressed by η and ζ for small cratering impact. Here, ζLis the spin angular momentum that the target acquires at impact divided by the collisional angular momentum due to the projectile. This is an important parameter to study the collisional evolution of asteroid rotation. For a spherical target, ζLis shown to be well approximated by ζ.

  9. A qualitative case study of evaluation use in the context of a collaborative program evaluation strategy in Burkina Faso.

    PubMed

    D'Ostie-Racine, Léna; Dagenais, Christian; Ridde, Valéry

    2016-05-26

    Program evaluation is widely recognized in the international humanitarian sector as a means to make interventions and policies more evidence based, equitable, and accountable. Yet, little is known about the way humanitarian non-governmental organizations (NGOs) actually use evaluations. The current qualitative evaluation employed an instrumental case study design to examine evaluation use (EU) by a humanitarian NGO based in Burkina Faso. This organization developed an evaluation strategy in 2008 to document the implementation and effects of its maternal and child healthcare user fee exemption program. Program evaluations have been undertaken ever since, and the present study examined the discourses of evaluation partners in 2009 (n = 15) and 2011 (n = 17). Semi-structured individual interviews and one group interview were conducted to identify instances of EU over time. Alkin and Taut's (Stud Educ Eval 29:1-12, 2003) conceptualization of EU was used as the basis for thematic qualitative analyses of the different forms of EU identified by stakeholders of the exemption program in the two data collection periods. Results demonstrated that stakeholders began to understand and value the utility of program evaluations once they were exposed to evaluation findings and then progressively used evaluations over time. EU was manifested in a variety of ways, including instrumental and conceptual use of evaluation processes and findings, as well as the persuasive use of findings. Such EU supported planning, decision-making, program practices, evaluation capacity, and advocacy. The study sheds light on the many ways evaluations can be used by different actors in the humanitarian sector. Conceptualizations of EU are also critically discussed.

  10. Masonry Program Standards.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. Dept. of Vocational Education.

    This publication contains statewide standards for the masonry program in Georgia. The standards are divided into 12 categories: foundations (philosophy, purpose, goals, program objectives, availability, evaluation); admissions (admission requirements, provisional admission requirements, recruitment, evaluation and planning); program structure…

  11. Evaluating an employee wellness program.

    PubMed

    Mukhopadhyay, Sankar; Wendel, Jeanne

    2013-12-01

    What criteria should be used to evaluate the impact of a new employee wellness program when the initial vendor contract expires? Published academic literature focuses on return-on-investment as the gold standard for wellness program evaluation, and a recent meta-analysis concludes that wellness programs can generate net savings after one or two years. In contrast, surveys indicate that fewer than half of these programs report net savings, and actuarial analysts argue that return-on-investment is an unrealistic metric for evaluating new programs. These analysts argue that evaluation of new programs should focus on contract management issues, such as the vendor's ability to: (i) recruit employees to participate and (ii) induce behavior change. We compute difference-in-difference propensity score matching estimates of the impact of a wellness program implemented by a mid-sized employer. The analysis includes one year of pre-implementation data and three years of post-implementation data. We find that the program successfully recruited a broad spectrum of employees to participate, and it successfully induced short-term behavior change, as manifested by increased preventive screening. However, the effects on health care expenditures are positive (but insignificant). If it is unrealistic to expect new programs to significantly reduce healthcare costs in a few years, then focusing on return-on-investment as the gold standard metric may lead to early termination of potentially useful wellness programs. Focusing short-term analysis of new programs on short-term measures may provide a more realistic evaluation strategy.

  12. Evaluacion de que consister y por que se lleva acabo? (Evaluation: What Does it Consist of, and for What Purpose?).

    ERIC Educational Resources Information Center

    Austin Independent School District, TX. Office of Research and Evaluation.

    A guide is presented for the evaluation of the bilingual programs in the Austin, Texas, Independent School District. The reasons for an evaluation and a definition of program objectives and evaluation instruments are given. The program components, objectives and evaluation instruments for each grade level (K-4) are listed. The components involved…

  13. Compulsory Project-Level Involvement and the Use of Program-Level Evaluations: Evaluating the Local Systemic Change for Teacher Enhancement Program

    ERIC Educational Resources Information Center

    Johnson, Kelli; Weiss, Iris R.

    2011-01-01

    In 1995, the National Science Foundation (NSF) contracted with principal investigator Iris Weiss and an evaluation team at Horizon Research, Inc. (HRI) to conduct a national evaluation of the Local Systemic Change for Teacher Enhancement program (LSC). HRI conducted the core evaluation under a $6.25 million contract with NSF. This program…

  14. Report of the Evaluation of the Race/Human Relations Program. Student and Staff Program and Long Range Goals. Baseline Year 1982-83. Evaluation Services Department Report No. 348.

    ERIC Educational Resources Information Center

    Tomblin, Elizabeth A.; And Others

    In response to a 1982 Superior Court order, a centrally developed, sequential program for improving race/human relations in the San Diego City Schools was developed and field tested or implemented during the 1982-83 school year. This systematic evaluation reports on the student program, "Conflict"; the staff program; and baseline data…

  15. Improving the Impact and Implementation of Disaster Education: Programs for Children Through Theory-Based Evaluation.

    PubMed

    Johnson, Victoria A; Ronan, Kevin R; Johnston, David M; Peace, Robin

    2016-11-01

    A main weakness in the evaluation of disaster education programs for children is evaluators' propensity to judge program effectiveness based on changes in children's knowledge. Few studies have articulated an explicit program theory of how children's education would achieve desired outcomes and impacts related to disaster risk reduction in households and communities. This article describes the advantages of constructing program theory models for the purpose of evaluating disaster education programs for children. Following a review of some potential frameworks for program theory development, including the logic model, the program theory matrix, and the stage step model, the article provides working examples of these frameworks. The first example is the development of a program theory matrix used in an evaluation of ShakeOut, an earthquake drill practiced in two Washington State school districts. The model illustrates a theory of action; specifically, the effectiveness of school earthquake drills in preventing injuries and deaths during disasters. The second example is the development of a stage step model used for a process evaluation of What's the Plan Stan?, a voluntary teaching resource distributed to all New Zealand primary schools for curricular integration of disaster education. The model illustrates a theory of use; specifically, expanding the reach of disaster education for children through increased promotion of the resource. The process of developing the program theory models for the purpose of evaluation planning is discussed, as well as the advantages and shortcomings of the theory-based approaches. © 2015 Society for Risk Analysis.

  16. Using a systems orientation and foundational theory to enhance theory-driven human service program evaluations.

    PubMed

    Wasserman, Deborah L

    2010-05-01

    This paper offers a framework for using a systems orientation and "foundational theory" to enhance theory-driven evaluations and logic models. The framework guides the process of identifying and explaining operative relationships and perspectives within human service program systems. Self-Determination Theory exemplifies how a foundational theory can be used to support the framework in a wide range of program evaluations. Two examples illustrate how applications of the framework have improved the evaluators' abilities to observe and explain program effect. In both exemplars improvements involved addressing and organizing into a single logic model heretofore seemingly disparate evaluation issues regarding valuing (by whose values); the role of organizational and program context; and evaluation anxiety and utilization. Copyright 2009 Elsevier Ltd. All rights reserved.

  17. Design and implementation of an integrated, continuous evaluation, and quality improvement system for a state-based home-visiting program.

    PubMed

    McCabe, Bridget K; Potash, Dru; Omohundro, Ellen; Taylor, Cathy R

    2012-10-01

    To describe the design and implementation of an evaluation system to facilitate continuous quality improvement (CQI) and scientific evaluation in a statewide home visiting program, and to provide a summary of the system's progress in meeting intended outputs and short-term outcomes. Help Us Grow Successfully (HUGS) is a statewide home visiting program that provides services to at-risk pregnant/post-partum women, children (0-5 years), and their families. The program goals are to improve parenting skills and connect families to needed services and thus improve the health of the service population. The evaluation system is designed to: (1) integrate evaluation into daily workflow; (2) utilize standardized screening and evaluation tools; (3) facilitate a culture of CQI in program management; and, (4) facilitate scientifically rigorous evaluations. The review of the system's design and implementation occurred through a formative evaluation process (reach, dose, and fidelity). Data was collected through electronic and paper surveys, administrative data, and notes from management meetings, and medical chart review. In the design phase, four process and forty outcome measures were selected and are tracked using standardized screening and monitoring tools. During implementation, the reach and dose of training were adequate to successfully launch the evaluation/CQI system. All staff (n = 165) use the system for management of families; the supervisors (n = 18) use the system to track routine program activities. Data quality and availability is sufficient to support periodic program reviews at the region and state level. In the first 7 months, the HUGS evaluation system tracked 3,794 families (7,937 individuals). System use and acceptance is high. A successful implementation of a structured evaluation system with a strong CQI component is feasible in an existing, large statewide program. The evaluation/CQI system is an effective mechanism to drive modest change in management of the program.

  18. Guidelines for Creating, Implementing, and Evaluating Mind-Body Programs in a Military Healthcare Setting.

    PubMed

    Smith, Katherine; Firth, Kimberly; Smeeding, Sandra; Wolever, Ruth; Kaufman, Joanna; Delgado, Roxana; Bellanti, Dawn; Xenakis, Lea

    2016-01-01

    Research suggests that the development of mind-body skills can improve individual and family resilience, particularly related to the stresses of illness, trauma, and caregiving. To operationalize the research evidence that mind-body skills help with health and recovery, Samueli Institute, in partnership with experts in mind-body programming, created a set of guidelines for developing and evaluating mind-body programs for service members, veterans, and their families. The Guidelines for Creating, Implementing, and Evaluating Mind-Body Programs in a Military Healthcare Setting outline key strategies and issues to consider when developing, implementing, and evaluating a mind-body focused family empowerment approach in a military healthcare setting. Although these guidelines were developed specifically for a military setting, most of the same principles can be applied to the development of programs in the civilian setting as well. The guidelines particularly address issues unique to mind-body programs, such as choosing evidence-based modalities, licensure and credentialing, safety and contraindications, and choosing evaluation measures that capture the holistic nature of these types of programs. The guidelines are practical, practice-based guidelines, developed by experts in the fields of program development and evaluation, mind-body therapies, patient- and family-centered care, as well as, experts in military and veteran's health systems. They provide a flexible framework to create mind-body family empowerment programs and describe important issues that program developers and evaluators are encouraged to address to ensure the development of the most impactful, successful, evidence-supported programs possible. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Positive youth development programs for adolescents with greater psychosocial needs: evaluation based on program implementers.

    PubMed

    Shek, Daniel T L; Ng, Catalina S M; Law, Moon Y M

    2017-02-01

    As program implementers' views are seldom included in program evaluation and there are few related studies in different Chinese communities, this study examined the perceptions of the program implementers who implemented the Tier 2 Program of the P.A.T.H.S. Program in Hong Kong. The Tier 2 Program was designed to promote the development of adolescents with greater psychosocial needs. In the community-based P.A.T.H.S. Project, 400 program implementers completed a subjective outcome evaluation form (Form D) for program implementers. Consistent with the previous findings, program implementers generally held positive views towards the program, implementers, and program effectiveness and their views towards these three domains did not differ across grades. In line with the hypotheses, perceived program quality and perceived implementer quality predicted program effectiveness. The present findings provided an alternative perspective showing that the Tier 2 Program was well received by the program implementers and they regarded the program to be beneficial to the program participants.

  20. Care management program evaluation: constituents, conflicts, and moves toward standardization.

    PubMed

    Long, D Adam; Perry, Theodore L; Pelletier, Kenneth R; Lehman, Gregg O

    2006-06-01

    Care management program evaluations bring together constituents from finance, medicine, and social sciences. The differing assumptions and scientific philosophies that these constituents bring to the task often lead to frustrations and even contentions. Given the forms and variations of care management programs, the difficulty associated with program outcomes measurement should not be surprising. It is no wonder then that methods for clinical and economic evaluations of program efficacy continue to be debated and have yet to be standardized. We describe these somewhat hidden processes, examine where the industry stands, and provide recommendations for steps to standardize evaluation methodology.

  1. Planning and Selecting Evaluation Designs for Leadership Training: A Toolkit for Nurse Managers and Educators.

    PubMed

    Dunne, Simon; Lunn, Cora; Kirwan, Marcia; Matthews, Anne; Condell, Sarah

    2015-01-01

    Leadership development training and education for nurses is a priority in modern health care systems. Consequently, effective evaluation of nurse leadership development programs is essential for managers and educators in health care organizations to determine the impact of such programs on staff behaviors and patient outcomes. Our team has identified a framework for the evaluation of the design and implementation of such programs. Following this, we provide practical tools for the selection of evaluation methodologies for leadership development programs for use by health care educators and program commissioners. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Faculty performance evaluation in accredited U.S. public health graduate schools and programs: a national study.

    PubMed

    Gimbel, Ronald W; Cruess, David F; Schor, Kenneth; Hooper, Tomoko I; Barbour, Galen L

    2008-10-01

    To provide baseline data on evaluation of faculty performance in U.S. schools and programs of public health. The authors administered an anonymous Internet-based questionnaire using PHP Surveyor. The invited sample consisted of individuals listed in the Council on Education for Public Health (CEPH) Directory of Accredited Schools and Programs of Public Health. The authors explored performance measures in teaching, research, and service, and assessed how faculty performance measures are used. A total of 64 individuals (60.4%) responded to the survey, with 26 (40.6%) reporting accreditation/reaccreditation by CEPH within the preceding 24 months. Although all schools and programs employ faculty performance evaluations, a significant difference exists between schools and programs in the use of results for merit pay increases and mentoring purposes. Thirty-one (48.4%) of the organizations published minimum performance expectations. Fifty-nine (92.2%) of the respondents counted number of publications, but only 22 (34.4%) formally evaluated their quality. Sixty-two (96.9%) evaluated teaching through student course evaluations, and only 29 (45.3%) engaged in peer assessment. Although aggregate results of teaching evaluation are available to faculty and administrators, this information is often unavailable to students and the public. Most schools and programs documented faculty service activities qualitatively but neither assessed it quantitatively nor evaluated its impact. This study provides insight into how schools and programs of public health evaluate faculty performance. Results suggest that although schools and programs do evaluate faculty performance on a basic level, many do not devote substantial attention to this process.

  3. Cancer Therapy Evaluation Program | Office of Cancer Genomics

    Cancer.gov

    The Cancer Therapy Evaluation Program (CTEP) seeks to improve the lives of cancer patients by finding better treatments, control mechanisms, and cures for cancer. CTEP funds a national program of cancer research, sponsoring clinical trials to evaluate new anti-cancer agents.

  4. 5 CFR 339.205 - Medical evaluation programs.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Medical evaluation programs. 339.205 Section 339.205 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS MEDICAL QUALIFICATION DETERMINATIONS Physical and Medical Qualifications § 339.205 Medical evaluation programs. Agencies...

  5. 5 CFR 339.205 - Medical evaluation programs.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Medical evaluation programs. 339.205 Section 339.205 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS MEDICAL QUALIFICATION DETERMINATIONS Physical and Medical Qualifications § 339.205 Medical evaluation programs. Agencies...

  6. The SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION program - Technology Profiles

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) program was created to evaluate new and promising treatment technologies for cleanup at hazardous waste sites. The mission of the SITE program is to encourage the development and routine use of innovative treatment technologie...

  7. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM - TECHNOLOGY PROFILES 4th Edition

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) Program evaluates new and promising treatment technologies for cleanup of hazardous waste sites. The program was created to encourage the development and routine use of innovative treatment technologies. As a result, the SI...

  8. 5 CFR 339.205 - Medical evaluation programs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Medical evaluation programs. 339.205 Section 339.205 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS MEDICAL QUALIFICATION DETERMINATIONS Physical and Medical Qualifications § 339.205 Medical evaluation programs. Agencies...

  9. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM ANNUAL REPORT TO CONGRESS FY 2002

    EPA Science Inventory

    This report details the Fiscal Year 2002 activities of the Superfund Innovative Technology Evaluation (SITE) Program. The Program focused on the remediation needs of the hazardous waste remediation community through demonstration and evaluation of innovative technologies for reme...

  10. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM ANNUAL REPORT TO CONGRESS FY 2001

    EPA Science Inventory

    This report details the fiscal year 2001 activities of the Superfund Innovative Technology Evaluation (SITE) Program. The Program focuses on the remediation needs of the hazardous waste remediation community through demonstration and evaluation of innovative technologies for re...

  11. Overview of a pharmacist anticoagulation certificate program.

    PubMed

    Kirk, Julienne K; Edwards, Rebecca; Brewer, Andrew; Miller, Cathey; Bray, Bryan; Groce, James B

    2017-07-01

    To describe the design of an ongoing anticoagulation certificate program and annual renewal update for pharmacists. Components of the anticoagulation certificate program include home study, pre- and posttest, live sessions, case discussions with evaluation and presentation, an implementation plan, and survey information (program evaluation and use in practice). Clinical reasoning skills were assessed through case work-up and evaluation prior to live presentation. An annual renewal program requires pharmacists to complete home study and case evaluations. A total of 361 pharmacists completed the anticoagulation certificate program between 2002 and 2015. Most (62%) practiced in ambulatory care and 38% in inpatient care settings (8% in both). In the past four years, 71% were working in or starting anticoagulation clinics in ambulatory and inpatient settings. In their evaluations of the program, an average of 90% of participants agreed or strongly agreed the lecture material was relevant and objectives were met. Pharmacists are able to apply knowledge and skills in management of anticoagulation. This structured practice-based continuing education program was intended to enhance pharmacy practice and has achieved that goal. The certificate program in anticoagulation was relevant to pharmacists who attended the program. Copyright © 2017. Published by Elsevier Inc.

  12. State Guidelines for School Athletic Programs.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento.

    The guidelines presented here are designed to assist school personnel in developing, administering, and evaluating school athletic programs in California. Topics include: (1) the basic philosophy for school athletic programs; (2) procedures for evaluating school athletic programs; (3) the three-phase school athletic program; (4) resources to…

  13. Evaluating theory-based evaluation: information, norms, and adherence.

    PubMed

    Jacobs, W Jake; Sisco, Melissa; Hill, Dawn; Malter, Frederic; Figueredo, Aurelio José

    2012-08-01

    Programmatic social interventions attempt to produce appropriate social-norm-guided behavior in an open environment. A marriage of applicable psychological theory, appropriate program evaluation theory, and outcome of evaluations of specific social interventions assures the acquisition of cumulative theory and the production of successful social interventions--the marriage permits us to advance knowledge by making use of both success and failures. We briefly review well-established principles within the field of program evaluation, well-established processes involved in changing social norms and social-norm adherence, the outcome of several program evaluations focusing on smoking prevention, pro-environmental behavior, and rape prevention and, using the principle of learning from our failures, examine why these programs often do not perform as expected. Finally, we discuss the promise of learning from our collective experiences to develop a cumulative science of program evaluation and to improve the performance of extant and future interventions. Copyright © 2012. Published by Elsevier Ltd.

  14. The effects of stakeholder involvement on perceptions of an evaluation's credibility.

    PubMed

    Jacobson, Miriam R; Azzam, Tarek

    2018-06-01

    This article presents a study of the effects of stakeholder involvement on perceptions of an evaluation's credibility. Crowdsourced members of the public and a group of educational administrators read a description of a hypothetical program and two evaluations of the program: one conducted by a researcher and one conducted by program staff (i.e. program stakeholders). Study participants were randomly assigned versions of the scenario with different levels of stakeholder credibility and types of findings. Results showed that both samples perceived the researcher's evaluation findings to be more credible than the program staff's, but that this difference was significantly reduced when the program staff were described to be highly credible. The article concludes with implications for theory and research on evaluation dissemination and stakeholder involvement. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Reading/Writing and Mathematics Instruction. CIPP Planning/Evaluation Report 95-018. Focus on Program Evaluation.

    ERIC Educational Resources Information Center

    Des Moines Public Schools, IA. Dept. of Information Management.

    The Chapter 1 reading, writing, and mathematics instruction programs of the Des Moines (Iowa) public schools were evaluated for the 1993-94 school year. These programs provided supplemental instruction for about 2,968 students in 1993-94 through six components: (1) schoolwide projects; (2) the Reading Recovery Program; (3) the Reading/Writing Lab…

  16. Qualitative Evaluation of Emotional Intelligence In-Service Program for Secondary School Teachers

    ERIC Educational Resources Information Center

    Fer, Seval

    2004-01-01

    This paper is an attempt to evaluate the Emotional Intelligence (EQ) In-Service Program on the basis of experiences of 20 secondary school teachers who attended the program in a private school in Turkey. A phenomenological approach, with a focus group method was used. The first objective of this study was to evaluate EQ program on the basis of…

  17. Impact Evaluation of the U.S. Department of Education's Student Mentoring Program. Final Report. NCEE 2009-4047

    ERIC Educational Resources Information Center

    Bernstein, Lawrence; Rappaport, Catherine Dun; Olsho, Lauren; Hunt, Dana; Levin, Marjorie

    2009-01-01

    This report summarizes the findings from a national evaluation of mentoring programs funded under the U.S. Department of Education's Student Mentoring Program. The impact evaluation used an experimental design in which students were randomly assigned to a treatment or control group. Thirty-two purposively selected School Mentoring Programs and…

  18. Evaluation of the Cosmetology Program at Caldwell Community College and Technical Institute--Fall, 1981.

    ERIC Educational Resources Information Center

    Pipes, V. David

    In fall 1981, the cosmetology program at Caldwell Community College and Technical Institute (CCC&TI) was evaluated as part of a process to create a model for the periodic evaluation of all occupational programs at the school. In addition to collecting information for planning and program improvement, the study sought to assess the achievement of…

  19. Process Evaluation of a School-Based Weight Gain Prevention Program: The Dutch Obesity Intervention in Teenagers (DOiT)

    ERIC Educational Resources Information Center

    Singh, A. S.; Chinapaw, M. J. M.; Brug, J.; van Mechelen, W.

    2009-01-01

    Health promotion programs benefit from an accompanying process evaluation since it can provide more insight in the strengths and weaknesses of a program. A process evaluation was conducted to assess the reach, implementation, satisfaction and maintenance of a school-based program aimed at the prevention of excessive weight gain among Dutch…

  20. Assessment of the Teaching Behavior of the Instructors of an Out-of-School Program

    ERIC Educational Resources Information Center

    Rodríguez-Naveiras, Elena; Borges, África

    2015-01-01

    Out-of-school programs for students with high abilities are especially relevant when their needs are not covered in formal education. The evaluation of these programs is essential and it can be carried out from different evaluative approaches. The evaluation of the behavior of the people who implement the programs is an important aspect in the…

  1. A Program Evaluation of a Special Education Day School for Students with Emotional and Behavioral Disabilities

    ERIC Educational Resources Information Center

    Klein-Lombardo, Lucinda

    2012-01-01

    The purpose of this study was the program evaluation of a special education day school compared to a set of best practice standards for school programs for students with emotional and behavioral disorders. This evaluation will enable the organization to make decisions about which aspects of the program to continue, strengthen, or discontinue. …

  2. Governor's Educator Excellence Grant (GEEG) Program: Year One Evaluation Report. Policy Evaluation Report

    ERIC Educational Resources Information Center

    Springer, Matthew G.; Podgursky, Michael J.; Lewis, Jessica L.; Ehlert, Mark W.; Gardner, Catherine G.; Ghoshdastidar, Bonnie; Lopez, Omar S.; Patterson, Christine H.; Taylor, Lori L.

    2007-01-01

    This report presents findings stemming from the first-year evaluation of the Governor's Educator Excellence Grant (GEEG) program, one of several statewide performance incentive programs in Texas. In the fall of 2006, the GEEG program made available non-competitive, three-year grants to 99 schools ranging from $60,000 to $220,000 per year. Grants…

  3. Measuring Success in Obesity Prevention: A Synthesis of Health Promotion Switzerland's Long-Term Monitoring and Evaluation Strategy

    PubMed Central

    Ackermann, Günter; Kirschner, Michael; Guggenbühl, Lisa; Abel, Bettina; Klohn, Axel; Mattig, Thomas

    2015-01-01

    Aims Since 2007, Health Promotion Switzerland has implemented a national priority program for a healthy body weight. This article provides insight into the methodological challenges and results of the program evaluation. Methods Evaluation of the long-term program required targeted monitoring and evaluation projects addressing different outcome levels. The evaluation was carried out according to the Swiss Model for Outcome Classification (SMOC), a model designed to classify the effects of health promotion and prevention efforts. Results The results presented in this article emphasize both content and methods. The national program successfully achieved outcomes on many different levels within complex societal structures. The evaluation system built around the SMOC enabled assessment of program progress and the development of key indicators. However, it is not possible to determine definitively to what extent the national program helped stabilize the prevalence of obesity in Switzerland. Conclusion The model has shown its utility in providing a basis for evaluation and monitoring of the national program. Continuous analysis of data from evaluation and monitoring has made it possible to check the plausibility of suspected causal relationships as well as to establish an overall perspective and assessment of effectiveness supported by a growing body of evidence. PMID:25765161

  4. Potential pros and cons of external healthcare performance evaluation systems: real-life perspectives on Iranian hospital evaluation and accreditation program

    PubMed Central

    Jaafaripooyan, Ebrahim

    2014-01-01

    Background: Performance evaluation is essential to quality improvement in healthcare. The current study has identified the potential pros and cons of external healthcare evaluation programs, utilizing them subsequently to look into the merits of a similar case in a developing country. Methods: A mixed method study employing both qualitative and quantitative data collection and analysis techniques was adopted to achieve the study end. Subject Matter Experts (SMEs) and professionals were approached for two-stage process of data collection. Results: Potential advantages included greater attractiveness of high accreditation rank healthcare organizations to their customers/purchasers and boosted morale of their personnel. Downsides, as such, comprised the programs’ over-reliance on value judgment of surveyors, routinization and incurring undue cost on the organizations. In addition, the improved, standardized care processes as well as the judgmental nature of program survey were associated, as pros and cons, to the program investigated by the professionals. Conclusion: Besides rendering a tentative assessment of Iranian hospital evaluation program, the study provides those running external performance evaluations with a lens to scrutinize the virtues of their own evaluation systems through identifying the potential advantages and drawbacks of such programs. Moreover, the approach followed could be utilized for performance assessment of similar evaluation programs. PMID:25279381

  5. Assessment and Evaluation of Primary Prevention in Spinal Cord Injury

    PubMed Central

    2013-01-01

    Although the incidence of spinal cord injury (SCI) is low, the consequences of this disabling condition are extremely significant for the individual, family, and the community. Sequelae occur in the physical, psychosocial, sexual, and financial arenas, making global prevention of SCI crucial. Understanding how to assess and evaluate primary prevention programs is an important competency for SCI professionals. Assessing a program’s success requires measuring processes, outcomes, and impact. Effective evaluation can lead future efforts for program design while ensuring accountability for the program itself. The intended impact of primary prevention programs for SCI is to decrease the number of individuals who sustain traumatic injury; many programs have process and outcome goals as well. An understanding of the basic types of evaluation, evaluation design, and the overall process of program evaluation is essential for ensuring that these programs are efficacious. All health care professionals have the opportunity to put prevention at the forefront of their practice. With the current paucity of available data, it is important that clinicians share their program design, their successes, and their failures so that all can benefit and future injury can be prevented. PMID:23678281

  6. Do Early Childhood Programs Have Lasting Effects on Children? Evaluation Science Brief

    ERIC Educational Resources Information Center

    National Forum on Early Childhood Program Evaluation, 2008

    2008-01-01

    "Evaluation Science Briefs" summarize the findings and implications of a recent study evaluating the effects of an early childhood program or environment. This Brief evaluates the study "Early Intervention in Low Birthweight Premature Infants: Results at 18 Years of Age for the Infant Health and Development Program (IHDP)" (M.C. McCormick, J.…

  7. The Development and Implementation of a Model for Evaluating Clinical Specialty Education Programs.

    ERIC Educational Resources Information Center

    McLean, James E.; And Others

    A new method for evaluating cancer education programs, using an external/internal evaluation team is outlined. The internal program staff are required to collect the data, arrange for a site visit, provide access to personnel, and make available other information requested by the evaluators. The external team consists of a dentist with oncological…

  8. Evaluating Youth Sexual Health Peer Education Programs: "Challenges and Suggestions for Effective Evaluation Practices"

    ERIC Educational Resources Information Center

    Jaworsky, Denise; Larkin, June; Sriranganathan, Gobika; Clout, Jerri; Janssen, Jesse; Campbell, Lisa; Flicker, Sarah; Stadnicki, Dan; Erlich, Leah; Flynn, Susan

    2013-01-01

    Although peer sexual health education is a common form of sexual health promotion for youth, systematic reviews of these programs are relatively rare. In this study we interviewed youth peer educators to inquire about their experience of program evaluation and their perception of what is needed to develop effective evaluation practices. Data were…

  9. Redesigning and Aligning Assessment and Evaluation for a Federally Funded Math and Science Teacher Educational Program

    ERIC Educational Resources Information Center

    Hardre, Patricia L.; Slater, Janis; Nanny, Mark

    2010-01-01

    This paper examines the redesign of evaluation components for a teacher professional development project funded by the National Science Foundation. It focuses on aligning evaluation instrumentation and strategies with program goals, research goals and program evaluation best practices. The study identifies weaknesses in the original (year 1)…

  10. School Community Education Program in New York City 1988-89. Volume II. OREA Evaluation Section Report.

    ERIC Educational Resources Information Center

    Guerrero, Frank; Abbott, Lori

    This second volume of a four-volume evaluation of the 1988-89 New York City School Community Education Program (also known as the Umbrella Program) comprises reports evaluating nine innovative elementary school projects on social, ethnical, and environmental studies, four of which included staff development workshops. Evaluation sources included…

  11. Mandarins and Lemons--The Executive Investment in Program Evaluation.

    ERIC Educational Resources Information Center

    MacDonald, Barry

    The author contends that within executive government, which already has all the information it needs to make decisions, program evaluation is seen as a symbolic rather than a substantive enterprise. If it is assumed that program evaluation is an end of policy, not a means, the reasons for government investment in evaluation include: (1) no choice;…

  12. Formative Evaluation of the No-Fee Teacher Education Program from the Students' Standpoint

    ERIC Educational Resources Information Center

    Han, Yumei; Hu, Meizhong; Li, Ling

    2013-01-01

    This exploratory case study applied a formative evaluation framework to evaluate the no-fee teacher education program at Southwest University. The study focused on the students' perspective and their perceptions of the program, both intrinsic and extrinsic. A self-evaluation checklist and a questionnaire were the instruments used to collect data.…

  13. Curriculum and Evaluation Guide for Safety Education Programs. Research and Evaluation Report Series No. 40.00.

    ERIC Educational Resources Information Center

    Lowry, Carlee S.

    Designed to assist Bureau of Indian Affairs school officials in the identification of safety education program needs, this evaluation guide focuses upon the basic operational components in a safety education program. The means for establishing an evaluation design for safety education are presented via a flexible model appropriate for most…

  14. Insourcing, Not Capacity Building, a Better Model for Sustained Program Evaluation

    ERIC Educational Resources Information Center

    Miller, Thomas I.; Kobayashi, Michelle M.; Noble, Paula M.

    2006-01-01

    Community-based organizations (CBOs), typically small and underfunded with transient staff members, are told by funders to care for clients and verify program value. To assist CBOs with evaluations that speak to program effectiveness, many funders wish to expand the evaluation capacity of CBO staff members so that evaluation will occur as long as…

  15. EVALUATION OF OXYGEN-ENRICHED MSW/SEWAGE SLUDGE CO-INCINERATION DEMONSTRATION PROGRAM

    EPA Science Inventory

    This report provides an evaluation of a two-phased demonstration program conducted for the U.S. Environmental Protection Agency's Municipal Solid Waste Innovative Technology Evaluation Program, and the results thereof, of a recently developed method of sewage sludge managemen...

  16. 7 CFR 3405.22 - Evaluation of program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Evaluation of program. 3405.22 Section 3405.22 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HIGHER EDUCATION CHALLENGE GRANTS PROGRAM Supplementary Information § 3405.22 Evaluation of...

  17. 7 CFR 3405.22 - Evaluation of program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Evaluation of program. 3405.22 Section 3405.22 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HIGHER EDUCATION CHALLENGE GRANTS PROGRAM Supplementary Information § 3405.22 Evaluation of...

  18. 7 CFR 3405.22 - Evaluation of program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Evaluation of program. 3405.22 Section 3405.22 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HIGHER EDUCATION CHALLENGE GRANTS PROGRAM Supplementary Information § 3405.22 Evaluation of...

  19. 7 CFR 3405.22 - Evaluation of program.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Evaluation of program. 3405.22 Section 3405.22 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HIGHER EDUCATION CHALLENGE GRANTS PROGRAM Supplementary Information § 3405.22 Evaluation of...

  20. Evaluation of a PhD Program: Paving the Way.

    ERIC Educational Resources Information Center

    Germain, Carol P.; And Others

    1994-01-01

    During the evolution of an evaluation process for the University of Pennsylvania's doctoral program in nursing, a task force developed criteria and sources for program evaluation and surveyed students, alumni, and faculty to write a self-study report for external reviewers. (JOW)

  1. Evaluation of a cross-sector community initiative partnership: delivering a local sport program.

    PubMed

    Kihl, Lisa A; Tainsky, Scott; Babiak, Kathy; Bang, Hyejin

    2014-06-01

    Corporate community initiatives (CCI) are often established via cross-sector partnerships with nonprofit agencies to address critical social problems. While there is a growing body of literature exploring the effectiveness and social impact of these partnerships, there is a limited evaluative research on the implementation and execution processes of CCIs. In this paper, we examined the implementation and operational processes in the delivery of a professional sport organization's CCI initiative using program theory evaluation. The findings showed discrepancies between the associate organization and the implementers regarding understanding and fulfilling responsibilities with performing certain aspects (maintaining accurate records and program marketing) of the service delivery protocol. Despite program stakeholders being satisfied overall with the program delivery, contradictions between program stakeholders' satisfaction in the quality of program delivery was found in critical components (marketing and communications) of the service delivery. We conclude that ongoing evaluations are necessary to pinpoint the catalyst of the discrepancies along with all partners valuing process evaluation in addition to outcome evaluation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Program Evaluation at Foothill College.

    ERIC Educational Resources Information Center

    Lowe, Irel D.

    Evaluation systems were designed for the assessment of the instructional and non-instructional programs at Foothill College (California) to determine whether the objectives of the programs were being met and to ascertain the direct and indirect costs of the programs. For the instructional programs, criteria for determining effectiveness, revenue…

  3. 7 CFR 225.15 - Management responsibilities of sponsors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... forms. Application forms or descriptive materials given to households about applying for free meals must... evaluate, fund, or determine benefits for their programs, and with auditors for program reviews and law... programs to help them evaluate, fund, or determine benefits for their programs; auditors for program...

  4. Comparative Evaluation of Financing Programs: Insights From California’s Experience

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deason, Jeff

    Berkeley Lab examines criteria for a comparative assessment of multiple financing programs for energy efficiency, developed through a statewide public process in California. The state legislature directed the California Alternative Energy and Advanced Transportation Financing Authority (CAEATFA) to develop these criteria. CAEATFA's report to the legislature, an invaluable reference for other jurisdictions considering these topics, discusses the proposed criteria and the rationales behind them in detail. Berkeley Lab's brief focuses on several salient issues that emerged during the criteria development and discussion process. Many of these issues are likely to arise in other states that plan to evaluate the impactsmore » of energy efficiency financing programs, whether for a single program or multiple programs. Issues discussed in the brief include: -The stakeholder process to develop the proposed assessment criteria -Attribution of outcomes - such as energy savings - to financing programs vs. other drivers -Choosing the outcome metric of primary interest: program take-up levels vs. savings -The use of net benefits vs. benefit-cost ratios for cost-effectiveness evaluation -Non-energy factors -Consumer protection factors -Market transformation impacts -Accommodating varying program goals in a multi-program evaluation -Accounting for costs and risks borne by various parties, including taxpayers and utility customers, in cost-effectiveness analysis -How to account for potential synergies among programs in a multi-program evaluation« less

  5. Are You Making an Impact? Evaluating the Population Health Impact of Community Benefit Programs.

    PubMed

    Rains, Catherine M; Todd, Greta; Kozma, Nicole; Goodman, Melody S

    The Patient Protection and Affordable Care Act includes a change to the IRS 990 Schedule H, requiring nonprofit hospitals to submit a community health needs assessment every 3 years. Such health care entities are challenged to evaluate the effectiveness of community benefit programs addressing the health needs identified. In an effort to determine the population health impact of community benefit programs in 1 hospital outreach department, researchers and staff conducted an impact evaluation to develop priority areas and overarching goals along with program- and department-level objectives. The longitudinal impact evaluation study design consists of retrospective and prospective secondary data analyses. As an urban pediatric hospital, St Louis Children's Hospital provides an array of community benefit programs to the surrounding community. Hospital staff and researchers came together to form an evaluation team. Data from program evaluation and administrative data for analysis were provided by hospital staff. Impact scores were calculated by scoring objectives as met or unmet and averaged across goals to create impact scores that measure how closely programs meet the overarching departmental mission and goals. Over the 4-year period, there is an increasing trend in program-specific impact scores across all programs except one, Healthy Kids Express Asthma, which had a slight decrease in year 4 only. Current work in measuring and assessing the population health impact of community benefit programs is mostly focused on quantifying dollars invested into community benefit work rather than measuring the quality and impact of services. This article provides a methodology for measuring population health impact of community benefit programs that can be used to evaluate the effort of hospitals in providing community benefit. This is particularly relevant in our changing health care climate, as hospitals are being asked to justify community benefit and make meaningful contributions to population health. The Patient Protection and Affordable Care Act includes a change to the IRS 990 Schedule H, requiring nonprofit hospitals to submit a community health needs assessment every 3 years, and requires evaluation of program effectiveness; yet, it does not require any quantification of the impact of community benefit programs. The IRS Schedule H 990 policies could be strengthened by requiring an impact evaluation such as outlined in this article. As hospitals are being asked to justify community benefit and make meaningful contributions to population health, impact evaluations can be utilized to demonstrate the cumulative community benefit of programs and assess population health impact of community benefit programs.

  6. Evaluation of the Washington, D.C. Parking Enforcement Program

    DOT National Transportation Integrated Search

    1982-09-01

    This report documents the evaluation of the Washington, DC, parking enforcement program. This comprehensive program is operated by the District of Columbia, Department of Transportation (DC DOT). The program has resulted in the successful integration...

  7. Assessment of Learning and Program Evaluation in Health Professions Education Programs

    ERIC Educational Resources Information Center

    Moore, Donald E., Jr.

    2018-01-01

    This chapter proposes approaches for assessing learners and evaluating courses and curriculum that could be used by directors of health professions education (HPE) programs to determine the effectiveness and impact of their programs.

  8. Methodology for the evaluation of the Stephanie Alexander Kitchen Garden program.

    PubMed

    Gibbs, L; Staiger, P K; Townsend, M; Macfarlane, S; Gold, L; Block, K; Johnson, B; Kulas, J; Waters, E

    2013-04-01

    Community and school cooking and gardening programs have recently increased internationally. However, despite promising indications, there is limited evidence of their effectiveness. This paper presents the evaluation framework and methods negotiated and developed to meet the information needs of all stakeholders for the Stephanie Alexander Kitchen Garden (SAKG) program, a combined cooking and gardening program implemented in selectively funded primary schools across Australia. The evaluation used multiple aligned theoretical frameworks and models, including a public health ecological approach, principles of effective health promotion and models of experiential learning. The evaluation is a non-randomised comparison of six schools receiving the program (intervention) and six comparison schools (all government-funded primary schools) in urban and rural areas of Victoria, Australia. A mixed-methods approach was used, relying on qualitative measures to understand changes in school cultures and the experiential impacts on children, families, teachers, parents and volunteers, and quantitative measures at baseline and 1 year follow up to provide supporting information regarding patterns of change. The evaluation study design addressed the limitations of many existing evaluation studies of cooking or garden programs. The multistrand approach to the mixed methodology maintained the rigour of the respective methods and provided an opportunity to explore complexity in the findings. Limited sensitivity of some of the quantitative measures was identified, as well as the potential for bias in the coding of the open-ended questions. The SAKG evaluation methodology will address the need for appropriate evaluation approaches for school-based kitchen garden programs. It demonstrates the feasibility of a meaningful, comprehensive evaluation of school-based programs and also demonstrates the central role qualitative methods can have in a mixed-method evaluation. So what? This paper contributes to debate about appropriate evaluation approaches to meet the information needs of all stakeholders and will support the sharing of measures and potential comparisons between program outcomes for comparable population groups and settings.

  9. Building an Evidence Base to Inform Interventions for Pregnant and Parenting Adolescents: A Call for Rigorous Evaluation

    PubMed Central

    Burrus, Barri B.; Scott, Alicia Richmond

    2012-01-01

    Adolescent parents and their children are at increased risk for adverse short- and long-term health and social outcomes. Effective interventions are needed to support these young families. We studied the evidence base and found a dearth of rigorously evaluated programs. Strategies from successful interventions are needed to inform both intervention design and policies affecting these adolescents. The lack of rigorous evaluations may be attributable to inadequate emphasis on and sufficient funding for evaluation, as well as to challenges encountered by program evaluators working with this population. More rigorous program evaluations are urgently needed to provide scientifically sound guidance for programming and policy decisions. Evaluation lessons learned have implications for other vulnerable populations. PMID:22897541

  10. Competency-based goals, objectives, and linked evaluations for rheumatology training programs: a standardized template of learning activities from the Carolinas Fellows Collaborative.

    PubMed

    Criscione-Schreiber, Lisa G; Bolster, Marcy B; Jonas, Beth L; O'Rourke, Kenneth S

    2013-06-01

    American Council on Graduate Medical Education program requirements mandate that rheumatology training programs have written goals, objectives, and performance evaluations for each learning activity. Since learning activities are similar across rheumatology programs, we aimed to create competency-based goals and objectives (CBGO) and evaluations that would be generalizable nationally. Through an established collaboration of the 4 training programs' directors in North Carolina and South Carolina, we collaboratively composed CBGO and evaluations for each learning activity for rheumatology training programs. CBGO and linked evaluations were written using appropriate verbs based on Bloom's taxonomy. Draft documents were peer reviewed by faculty at the 4 institutions and by members of the American College of Rheumatology (ACR) Clinician Scholar Educator Group. We completed templates of CBGO for core and elective rotations and conferences. Templates detail progressive fellow performance improvement appropriate to educational level. Specific CBGO are mirrored in learning activity evaluations. Templates are easily modified to fit individual program attributes, have been successfully implemented by our 4 programs, and have proven their value in 4 residency review committee reviews. We propose adoption of these template CBGO by the ACR, with access available to all rheumatology training programs. Evaluation forms that exactly reflect stated objectives ensure that trainees are assessed using standardized measures and that trainees are aware of the learning expectations. The objectives mirrored in the evaluations closely align with the proposed milestones for internal medicine training, and will therefore be a useful starting point for creating these milestones in rheumatology. Copyright © 2013 by the American College of Rheumatology.

  11. Apollo Photograph Evaluation (APE) programming manual

    NASA Technical Reports Server (NTRS)

    Kim, I. J.

    1974-01-01

    This document describes the programming techniques used to implement the equations of the Apollo Photograph Evaluation (APE) program on the UNIVAC 1108 computer and contains detailed descriptions of the program structure, a User's Guide section to provide the necessary information for proper operation of the program, and information for the assessment of the program's adaptability to future problems.

  12. An overview of the effectiveness and efficiency of HIV prevention programs.

    PubMed Central

    Holtgrave, D R; Qualls, N L; Curran, J W; Valdiserri, R O; Guinan, M E; Parra, W C

    1995-01-01

    Because of the enormity of the HIV-AIDS epidemic and the urgency for preventing transmission, HIV prevention programs are a high priority for careful and timely evaluations. Information on program effectiveness and efficiency is needed for decision-making about future HIV prevention priorities. General characteristics of successful HIV prevention programs, programs empirically evaluated and found to change (or not change) high-risk behaviors or in need of further empirical study, and economic evaluations of certain programs are described and summarized with attention limited to programs that have a behavioral basis. HIV prevention programs have an impact on averting or reducing risk behaviors, particularly when they are delivered with sufficient resources, intensity, and cultural competency and are based on a firm foundation of behavioral and social science theory and past research. Economic evaluations have found that some of these behaviorally based programs yield net economic benefits to society, and others are likely cost-effective (even if not cost-saving) relative to other health programs. Still, specific improvements should be made in certain HIV prevention programs. PMID:7630989

  13. Procedures for Comparing Instructional Programs.

    ERIC Educational Resources Information Center

    Klein, Stephen

    This paper examines comparative educational program evaluation. Suggested evaluative criteria and evaluation techniques and their weaknesses are discussed. An evaluation formula is proposed, and an example of its operation is provided. (DG)

  14. ENVIRONMENTAL, ECONOMIC AND ENERGY IMPACTS OF MATERIAL RECOVERY FACILITIES - A MITE PROGRAM EVALUATION

    EPA Science Inventory

    This report documents an evaluation of the environmental, economic, and energy impacts of material recovery facilities (MRFS) conducted under the Municipal Solid Waste Innovative Technology Evaluation (MITE) Program. he MITE Program is sponsored by the U.S. Environmental Protecti...

  15. Evaluating Afterschool Programs

    ERIC Educational Resources Information Center

    Little, Priscilla M.

    2014-01-01

    Well-implemented afterschool programs can promote a range of positive learning and developmental outcomes. However, not all research and evaluation studies have shown the benefits of participation, in part because programs and their evaluation were out of sync. This chapter provides practical guidance on how to foster that alignment between…

  16. Evaluation of Career Development Programs from an Action Perspective.

    ERIC Educational Resources Information Center

    Young, Richard A.; Valach, Ladislav

    1994-01-01

    Presents action-theoretical approach to evaluation of career development programs based on constructionist epistemology. Propositions from action-theoretical perspective center around career and action as related, interpretative constructs. Propositions give rise to implications for evaluation of career programs that address ongoing nature of…

  17. Evaluating public participation in environmental decision-making: EPA's superfund community involvement program.

    PubMed

    Charnley, Susan; Engelbert, Bruce

    2005-11-01

    This article discusses an 8-year, ongoing project that evaluates the Environmental Protection Agency's Superfund community involvement program. The project originated as a response to the Government Performance and Results Act, which requires federal agencies to articulate program goals, and evaluate and report their progress in meeting those goals. The evaluation project assesses how effective the Superfund community involvement program is in promoting public participation in decisions about how to clean up hazardous wastes at Superfund sites. We do three things in the article: (1) share our experience with evaluating an Agency public participation program, including lessons learned about methods of evaluation; (2) report evaluation results; and (3) address a number of issues pertaining to the evaluation of public participation in environmental decision-making. Our goal is to encourage more environmental managers to incorporate evaluation into their public participation programs as a tool for improving them. We found that written mail surveys were an effective and economical tool for obtaining feedback on EPA's community involvement program at Superfund sites. The evaluation focused on four criteria: citizen satisfaction with EPA information about the Superfund site, citizen understanding of environmental and human health risks associated with the site, citizen satisfaction with opportunities provided by EPA for community input, and citizen satisfaction with EPA's response to community input. While the evaluation results were mixed, in general, community members who were most informed about and involved in the cleanup process at Superfund sites generally were also the most satisfied with the community involvement process, and the job that EPA was doing cleaning up the site. We conclude that systematic evaluation provides meaningful and useful information that agencies can use to improve their public participation programs. However, there need to be institutionalized processes that ensure evaluation results are used to develop and implement strategies for improvement.

  18. Evaluation: Review of the Past, Preview of the Future.

    ERIC Educational Resources Information Center

    Smith, M. F.

    1994-01-01

    This paper summarized contributors' ideas about evaluation as a field and where it is going. Topics discussed were qualitative versus quantitative debate; evaluation's purpose; professionalization; program failure; program development; evaluators as advocates; evaluation knowledge; evaluation expansion; and methodology and design. (SLD)

  19. Community outreach: from measuring the difference to making a difference with health information*

    PubMed Central

    Ottoson, Judith M.; Green, Lawrence W.

    2005-01-01

    Background: Community-based outreach seeks to move libraries beyond their traditional institutional boundaries to improve both access to and effectiveness of health information. The evaluation of such outreach needs to involve the community in assessing the program's process and outcomes. Purpose: Evaluation of community-based library outreach programs benefits from a participatory approach. To explain this premise of the paper, three components of evaluation theory are paired with relevant participatory strategies. Concepts: The first component of evaluation theory is also a standard of program evaluation: use. Evaluation is intended to be useful for stakeholders to make decisions. A useful evaluation is credible, timely, and of adequate scope. Participatory approaches to increase use of evaluation findings include engaging end users early in planning the program itself and in deciding on the outcomes of the evaluation. A second component of evaluation theory seeks to understand what is being evaluated, such as specific aspects of outreach programs. A transparent understanding of the ways outreach achieves intended goals, its activities and linkages, and the context in which it operates precedes any attempt to measure it. Participatory approaches to evaluating outreach include having end users, such as health practitioners in other community-based organizations, identify what components of the outreach program are most important to their work. A third component of evaluation theory is concerned with the process by which value is placed on outreach. What will count as outreach success or failure? Who decides? Participatory approaches to valuing include assuring end-user representation in the formulation of evaluation questions and in the interpretation of evaluation results. Conclusions: The evaluation of community-based outreach is a complex process that is not made easier by a participatory approach. Nevertheless, a participatory approach is more likely to make the evaluation findings useful, ensure that program knowledge is shared, and make outreach valuing transparent. PMID:16239958

  20. 23 CFR 637.207 - Quality assurance program.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... independent assurance (IA) program consisting of the following: (1) Acceptance program. (i) Each STD's... quality control samples. (C) The quality control sampling and testing is evaluated by an IA program. (iii... appropriate. See 23 CFR 635.413(e) for specific requirements. (2) The IA program shall evaluate the qualified...

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