Science.gov

Sample records for instrumented charpy impact

  1. Charpy impact test results on five materials and NIST verification specimens using instrumented 2-mm and 8-mm strikers

    SciTech Connect

    Nanstad, R.K.; Sokolov, M.A.

    1995-04-01

    The Heavy-Section Steel Irradiation Program at Oak Ridge National Laboratory is involved in two cooperative projects, with international participants, both of which involve Charpy V-notch impact tests with instrumented strikers of 2mm and 8mm radii. Two heats of A 533 grade B class I pressure vessel steel and a low upper-shelf (LUS) submerged-arc (SA) weld were tested on the same Charpy machine, while one heat of a Russian Cr-Mo-V forging steel and a high upper-shelf (HUS) SA weld were tested on two different machines. The number of replicate tests at any one temperature ranged from 2 to 46 specimens. Prior to testing with each striker, verification specimens at the low, high, and super high energy levels from the National Institute of Standards and Technology (NIST) were tested. In the two series of verification tests, the tests with the 2mm striker met the requirements at the low and high energy levels but not at the super high energy. For one plate, the 2mm striker showed somewhat higher average absorbed energies than those for the 8-mm striker at all three test temperatures. For the second plate and the LUS weld, however, the 2mm striker showed somewhat lower energies at both test temperatures. For the Russian forging steel and the HUS weld, tests were conducted over a range of temperatures with tests at one laboratory using the 8mm striker and tests at a second laboratory using the 2mm striker. Lateral expansion was measured for all specimens and the results are compared with the absorbed energy results. The overall results showed generally good agreement (within one standard deviation) in energy measurements by the two strikers. Load-time traces from the instrumented strikers were also compared and used to estimate shear fracture percentage. Four different formulas from the European Structural Integrity Society draft standard for instrumented Charpy test are compared and a new formula is proposed for estimation of percent shear from the force-time trace.

  2. Low blow Charpy impact of silicon carbides

    NASA Technical Reports Server (NTRS)

    Abe, H.; Chandan, H. C.; Bradt, R. C.

    1978-01-01

    The room-temperature impact resistance of several commercial silicon carbides was examined using an instrumented pendulum-type machine and Charpy-type specimens. Energy balance compliance methods and fracture toughness approaches, both applicable to other ceramics, were used for analysis. The results illustrate the importance of separating the machine and the specimen energy contributions and confirm the equivalence of KIc and KId. The material's impact energy was simply the specimen's stored elastic strain energy at fracture.

  3. Quality assurance of absorbed energy in Charpy impact test

    NASA Astrophysics Data System (ADS)

    Rocha, C. L. F.; Fabricio, D. A. K.; Costa, V. M.; Reguly, A.

    2016-07-01

    In order to ensure the quality assurance and comply with standard requirements, an intralaboratory study has been performed for impact Charpy tests, involving two operators. The results based on ANOVA (Analysis of Variance) and Normalized Error statistical techniques pointed out that the execution of the tests is appropriate, because the implementation of quality assurance methods showed acceptable results.

  4. Microstructural characterization of Charpy-impact-tested nanostructured bainite

    SciTech Connect

    Tsai, Y.T.; Chang, H.T.; Huang, B.M.; Huang, C.Y.; Yang, J.R.

    2015-09-15

    In this work, a possible cause of the extraordinary low impact toughness of nanostructured bainite has been investigated. The microstructure of nanostructured bainite consisted chiefly of carbide-free bainitic ferrite with retained austenite films. X-ray diffractometry (XRD) measurement indicated that no retained austenite existed in the fractured surface of the Charpy-impact-tested specimens. Fractographs showed that cracks propagated mainly along bainitic ferrite platelet boundaries. The change in microstructure after impact loading was verified by transmission electron microscopy (TEM) observations, confirming that retained austenite was completely transformed to strain-induced martensite during the Charpy impact test. However, the zone affected by strained-induced martensite was found to be extremely shallow, only to a depth of several micrometers from the fracture surface. It is appropriately concluded that upon impact, as the crack forms and propagates, strain-induced martensitic transformation immediately occurs ahead of the advancing crack tip. The successive martensitic transformation profoundly facilitates the crack propagation, resulting in the extremely low impact toughness of nanostructured bainite. Retained austenite, in contrast to its well-known beneficial role, has a deteriorating effect on toughness during the course of Charpy impact. - Highlights: • The microstructure of nanostructured bainite consisted of nano-sized bainitic ferrite subunits with retained austenite films. • Special sample preparations for SEM, XRD and TEM were made, and the strain-affected structures have been explored. • Retained austenite films were found to transform into martensite after impact loading, as evidenced by XRD and TEM results. • The zone of strain-induced martensite was found to extend to only several micrometers from the fracture surface. • The poor Charpy impact toughness is associated with the fracture of martensite at a high strain rate during

  5. Charpy impact test results for low-activation ferritic alloys

    SciTech Connect

    Cannon, N.S.; Hu, W.L.; Gelles, D.S.

    1987-05-01

    The objective of this work is to evaluate the shift of the ductile to brittle transition temperature (DBTT) and the reduction of the upper shelf energy (USE) due to neutron irradiation of low activation ferritic alloys. Six low activation ferritic alloys have been tested following irradiation at 365/sup 0/C to 10 dpa and compared with control specimens in order to assess the effect of irradiation on Charpy impact properties.

  6. Charpy Impact Energy and Microindentation Hardness of 60-NITINOL

    NASA Technical Reports Server (NTRS)

    Stanford, Malcolm K.

    2012-01-01

    60-NITINOL (60 wt.% Ni 40 wt.% Ti) is being studied as a material for advanced aerospace components. The Charpy impact energy and microindentation hardness has been studied for this material, fabricated by vacuum induction skull melting (casting) and by hot isostatic pressing. Test specimens were prepared in various hardened and annealed heat treatment conditions. The average impact energy ranged from 0.33 to 0.49J for the hardened specimens while the annealed specimens had impact energies ranging from 0.89 to 1.18J. The average hardness values of the hardened specimens ranged from 590 to 676 HV while that of the annealed specimens ranged from 298 to 366 HV, suggesting an inverse relationship between impact energy and hardness. These results are expected to provide guidance in the selection of heat treatment processes for the design of mechanical components.

  7. The evaluation of tempered martensite embrittlement in 4130 steel by instrumented charpy V-notch testing

    NASA Astrophysics Data System (ADS)

    Zia-Ebrahimi, F.; Krauss, G.

    1983-06-01

    Tempered martensite embrittlement (TME) was studied in vacuum-melted 4130 steel with either 0.002 or 0.02 wt pct P. TME was observed as a severe decrease in Charpy V-notch impact energy, from 46 ft-lb. at 200 °C to 35 ft-lb. at 300 °C in the low P alloy. The impact energy of the high P alloy was consistently lower than that of the low P alloy in all tempered conditions. Fracture was transgranular for all specimens; therefore, segregation of P to the prior austenitic grain boundaries was not a factor in the o°Currence of TME. Analysis of load-time curves obtained by instrumented Charpy testing revealed that the embrittlement is associated with a drop in the pre-maximum-load and post-unstable-fracture energies. In specimens tempered at 400 °C the deleterious effect of phosphorus on impact energy became pronounced, a result more consistent with classical temper embrittlement rather than TME. A constant decrease in pre-maximum-load energy due to phosphorus content was observed. The pre-maximum-load energy decreases with increasing tempering temperature in the range of 200 °C to 400 °C, a result explained by the change in work hardening rate. Carbon extraction replicas of polished and etched as-quenched specimens revealed the presence of Fe2MoC and/or Fe3C carbides retained after austenitizing. Ductile crack extension close to the notch root was related to the formation of fine micro voids at the retained carbides.

  8. Current status of small specimen technology in Charpy impact testing

    NASA Astrophysics Data System (ADS)

    Kurishita, H.; Kayano, H.; Narui, M.; Yamazaki, M.

    1994-09-01

    The current status of small-scale specimen technology in Charpy impact testing for ferritic steels is presented, with emphasis on the effect of the notch dimensions (notch depth, notch root radius and notch angle) on the upper shelf energy (USE) and ductile-to-brittle transition temperature (DBTT). The USE for miniaturized specimens, normalized by Bb2 or ( Bb{3}/{2} ( B is the specimen thickness, b the ligament size), is essentially independent of notch geometry and has a linear relationship with the USE of full size specimens, regardless of irradiation and alloy conditions. The DBTT of miniaturized specimens depends strongly on the notch dimensions; this dependence of the DBTT decreases as the DBTT of full size specimens increase due to neutron irradiation or thermal aging. These results may be useful in determining the USE and DBTT for full size specimens from those for miniaturized specimens.

  9. Magnetic system for the quality control of specimens for Charpy impact test

    NASA Astrophysics Data System (ADS)

    Martin, R. V.; Castanho, M. A. P.

    2015-10-01

    It was developed a non-destructive testing system based on magnetic methods for characterization of steel specimens, used in calibration of Charpy impact testing machines. The magnetic properties saturation, remanence, coercivity, and the hysteresis curves were used to create a "magnetic signature" of reference to ensure the value of energy absorbed by these standard specimens.

  10. Microstructure and Charpy impact properties of 12 14Cr oxide dispersion-strengthened ferritic steels

    NASA Astrophysics Data System (ADS)

    Oksiuta, Z.; Baluc, N.

    2008-02-01

    This paper describes the microstructure and Charpy impact properties of 12-14 Cr ODS ferritic steels fabricated by mechanical alloying of pure Fe, Cr, W, Ti and Y 2O 3 powders in a Retsch ball mill in argon atmosphere, followed by hot isostatic pressing at 1100 °C under 200 MPa for 4 h and heat treatment at 850 °C for 1 h. Weak Charpy impact properties were obtained in the case of both types of as-hipped materials. In the case of 14Cr materials, the weak Charpy properties appeared related to a bimodal grain size distribution and a heterogeneous dislocation density between the coarse and fine grains. No changes in microstructure were evidenced after heat treatment at 850 °C. Significant improvement in the transition temperature and upper shelf energy of 12Cr materials was obtained by heat treatment at 850 °C for 1 h, which was attributed to the formation of smaller grains, homogenous in size and containing fewer dislocations, with respect to the as-hipped microstructure. This modified microstructure results in a good compromise between strength and Charpy impact properties.

  11. Tensile and charpy impact properties of irradiated reduced-activation ferritic steels

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.

    1996-10-01

    Tensile tests were conducted on eight reduced-activation Cr-W steels after irradiation to 15-17 and 26-29 dpa, and Charpy impact tests were conducted on the steels irradiated to 26-29 dpa. Irradiation was in the Fast Flux Test Facility at 365{degrees}C on steels containing 2.25-12% Cr, varying amounts of W, V, and Ta, and 0.1%C. Previously, tensile specimens were irradiated to 6-8 dpa and Charpy specimens to 6-8, 15-17, and 20-24 dpa. Tensile and Charpy specimens were also thermally aged to 20000 h at 365{degrees}C. Thermal aging had little effect on the tensile behavior or the ductile-brittle transition temperature (DBTT), but several steels showed a slight increase in the upper-shelf energy (USE). After {approx}7 dpa, the strength of the steels increased and then remained relatively unchanged through 26-29 dpa (i.e., the strength saturated with fluence). Post-irradiation Charpy impact tests after 26-29 dpa showed that the loss of impact toughness, as measured by an increase in DBTT and a decrease in the USE, remained relatively unchanged from the values after 20-24 dpa, which had been relatively unchanged from the earlier irradiations. As before, the two 9Cr steels were the most irradiation resistant.

  12. An automated digital data collection and analysis system for the Charpy Impact Tester

    NASA Technical Reports Server (NTRS)

    Kohne, Glenn S.; Spiegel, F. Xavier

    1994-01-01

    The standard Charpy Impact Tester has been modified by the addition of a system of hardware and software to improve the accuracy and consistency of measurements made during specimen fracturing experiments. An optical disc, light source, and detector generate signals that indicate the pendulum position as a function of time. These signals are used by a computer to calculate the velocity and kinetic energy of the pendulum as a function of its position.

  13. Fracture toughness and Charpy impact properties of several RAFMS before and after irradiation in HFIR

    NASA Astrophysics Data System (ADS)

    Sokolov, M. A.; Tanigawa, H.; Odette, G. R.; Shiba, K.; Klueh, R. L.

    2007-08-01

    As part of the development of candidate reduced-activation ferritic steels for fusion applications, several steels, namely F82H, 9Cr-2WVTa steels and F82H weld metal, are being investigated in the joint DOE-JAEA collaboration program. Within this program, three capsules containing a variety of specimen designs were irradiated at two design temperatures in the ORNL High Flux Isotope Reactor (HFIR). Two capsules, RB-11J and RB-12J, were irradiated in the HFIR removable beryllium positions with europium oxide (Eu 2O 3) thermal neutron shields in place. Specimens were irradiated up to 5 dpa. Capsule JP25 was irradiated in the HFIR target position to 20 dpa. The design temperatures were 300 °C and 500 °C. Precracked third-sized V-notch Charpy (3.3 × 3.3 × 25.4 mm) and 0.18 T DC(T) specimens were tested to determine transition and ductile shelf fracture toughness before and after irradiation. The master curve methodology was applied to evaluate the fracture toughness transition temperature, T0. Irradiation induced shifts of T0 and reductions of JQ were compared with Charpy V-notch impact properties. Fracture toughness and Charpy shifts were also compared to hardening results.

  14. Charpy impact test results for unirradiated tantalum, tungsten and molybdenum alloys

    SciTech Connect

    Gelles, D.S.; Cannon, N.S.; Hu, W.L.; Hack, J.

    1987-12-01

    Charpy impact tests have been performed on 1/2 sized CVN specimens of T-111, a tantalum based alloy, and two experimental alloys with rhenium additions for improved low temperature ductility, W-26Re and Mo-13Re. The tantalum alloy was found to have a ductile to brittle transition below /minus/175/degree/C whereas the rhenium containing alloys both had a DBTT above 250/degree/C. The high DBTT found for rhenium containing alloys appears to be an inherent property of the alloy class. 9 refs., 8 figs., 2 tabs.

  15. Validation Study of Unnotched Charpy and Taylor-Anvil Impact Experiments using Kayenta

    SciTech Connect

    Kamojjala, Krishna; Lacy, Jeffrey; Chu, Henry S.; Brannon, Rebecca

    2015-03-01

    Validation of a single computational model with multiple available strain-to-failure fracture theories is presented through experimental tests and numerical simulations of the standardized unnotched Charpy and Taylor-anvil impact tests, both run using the same material model (Kayenta). Unnotched Charpy tests are performed on rolled homogeneous armor steel. The fracture patterns using Kayenta’s various failure options that include aleatory uncertainty and scale effects are compared against the experiments. Other quantities of interest include the average value of the absorbed energy and bend angle of the specimen. Taylor-anvil impact tests are performed on Ti6Al4V titanium alloy. The impact speeds of the specimen are 321 m/s and 393 m/s. The goal of the numerical work is to reproduce the damage patterns observed in the laboratory. For the numerical study, the Johnson-Cook failure model is used as the ductile fracture criterion, and aleatory uncertainty is applied to rate-dependence parameters to explore its effect on the fracture patterns.

  16. Charpy impact tests on martensitic/ferritic steels after irradiation in SINQ target-3

    NASA Astrophysics Data System (ADS)

    Dai, Yong; Marmy, Pierre

    2005-08-01

    Charpy impact tests were performed on martensitic/ferritic (MF) steels T91, F82H, Optifer-V and Optimax-A/-C irradiated in SINQ Target-3 up to 7.5 dpa and 500 appm He in a temperature range of 120-195 °C. Results demonstrate that for all the four kinds of steels, the ductile-to-brittle transition temperature (DBTT) increases with irradiation dose. The difference in the DBTT shifts (ΔDBTT) of the different steels is not significant after irradiation in the SINQ target. The ΔDBTT data from the previous small punch (Δ DBTT SP) and the present Charpy impact (ΔDBTT CVN) tests can be correlated with the expression: Δ DBTT SP = 0.4ΔDBTT CVN. All the ΔDBTT data fall into a linear band when they are plotted versus helium concentration. The results indicate that helium effects on the embrittlement of MF steels are significant, particularly at higher concentrations. It suggests that MF steels may not be very suitable for applications at low temperatures in spallation irradiation environments where helium production is high.

  17. Effect of Cadmium Plating Thickness on the Charpy Impact Energy of Hydrogen-Charged 4340 Steel

    NASA Astrophysics Data System (ADS)

    Es-Said, O. S.; Alcisto, J.; Guerra, J.; Jones, E.; Dominguez, A.; Hahn, M.; Ula, N.; Zeng, L.; Ramsey, B.; Mulazimoglu, H.; Li, Yong-Jun; Miller, M.; Alrashid, J.; Papakyriakou, M.; Kalnaus, S.; Lee, E. W.; Frazier, W. E.

    2016-07-01

    Hydrogen was intentionally introduced into ultra-high strength steel by cadmium plating. The purpose was to examine the effect of cadmium plate thickness and hence hydrogen on the impact energy of the steel. The AISI 4340 steel was austenitized at 1000 °C for 1 h, water quenched, and tempered at temperatures between 257 and 593 °C in order to achieve a range of targeted strength levels. The specimens were cadmium plated with 0.00508 mm (0.2 mils), 0.00762 mm (0.3 mils), and 0.0127 mm (0.5 mils). Results demonstrated that the uncharged specimens exhibited higher impact energy values when compared to the plated specimens at all tempering temperatures. The cadmium-plated specimens had very low Charpy impact values irrespective of their ultimate tensile strength values. The model of hydrogen transport by mobile dislocations to the fracture site appears to provide the most suitable explanation of the results.

  18. The production of calibration specimens for impact testing of subsize Charpy specimens

    SciTech Connect

    Alexander, D.J.; Corwin, W.R.; Owings, T.D.

    1994-09-01

    Calibration specimens have been manufactured for checking the performance of a pendulum impact testing machine that has been configured for testing subsize specimens, both half-size (5.0 {times} 5.0 {times} 25.4 mm) and third-size (3.33 {times} 3.33 {times} 25.4 mm). Specimens were fabricated from quenched-and-tempered 4340 steel heat treated to produce different microstructures that would result in either high or low absorbed energy levels on testing. A large group of both half- and third-size specimens were tested at {minus}40{degrees}C. The results of the tests were analyzed for average value and standard deviation, and these values were used to establish calibration limits for the Charpy impact machine when testing subsize specimens. These average values plus or minus two standard deviations were set as the acceptable limits for the average of five tests for calibration of the impact testing machine.

  19. Response of unirradiated and neutron-irradiated vanadium alloys to Charpy-impact loading*1

    NASA Astrophysics Data System (ADS)

    Loomis, B. A.; Smith, D. L.

    1991-03-01

    The ductile-brittle transition temperature (DBTT) was determined by Charpy-impact tests for dehydrogenated ( < 30 appm H) and hydrogenated (400-1200 appm H) V-7.2Cr-14.5Ti, V-9.9Cr-9.2Ti, V-13.5Cr-5.2Ti, V-17.7Ti, V-9.2Cr-4.9Ti, V-9.0Cr-3.2Fe-1.2Zr, V-3.1Ti-0.5Si, V-4.1Cr-4.3Ti, V-4.6Ti, and V-2.5Ti-1.0Si alloys. The DBTT was also determined for V-13.5Cr-5.2Ti, V-9.2Cr-4.9Ti, V-7.2Cr-14.5Ti, and V-17.7Ti alloys after neutron irradiation at 420 and 600°C to 41-44 dpa. The DBTTs determined for these vanadium alloys show that a vanadium alloy containing Cr and/or Ti and Si alloying additions to be used as a structural material in a fusion reactor should contain 3-9 wt% total alloying addition for maximum resistance to hydrogen- and/or irradiation-induced embrittlement.

  20. A reassessment of the effects of helium on Charpy impact properties of ferritic/martensitic steels

    SciTech Connect

    Gelles, D.S.; Hamilton, M.L.; Hankin, G.L.

    1998-03-01

    To test the effect of helium on Charpy impact properties of ferritic/martensitic steels, two approaches are reviewed: quantification of results of tests performed on specimens irradiated in reactors with very different neutron spectra, and isotopic tailoring experiments. Data analysis can show that if the differences in reactor response are indeed due to helium effects, then irradiation in a fusion machine at 400 C to 100 dpa and 1000 appm He will result in a ductile to brittle transition temperature shift of over 500 C. However, the response as a function of dose and helium level is unlikely to be simply due to helium based on physical reasoning. Shear punch tests and microstructural examinations also support this conclusion based on irradiated samples of a series of alloys made by adding various isotopes of nickel in order to vary the production of helium during irradiation in HFIR. The addition of nickel at any isotopic balance to the Fe-12Cr base alloy significantly increased the shear yield and maximum strengths of the alloys. However, helium itself, up to 75 appm at over 7 dpa appears to have little effect on the mechanical properties of the alloys. This behavior is instead understood to result from complex precipitation response. The database for effects of helium on embrittlement based on nickel additions is therefore probably misleading and experiments should be redesigned to avoid nickel precipitation.

  1. Effects of carbide precipitation on the strength and Charpy impact properties of low carbon Mn-Ni-Mo bainitic steels

    NASA Astrophysics Data System (ADS)

    Im, Young-Roc; Jun Oh, Yong; Lee, Byeong-Joo; Hwa Hong, Jun; Lee, Hu-Chul

    2001-08-01

    The effects of carbide precipitation on the strength and Charpy impact properties of tempered bainitic Mn-Ni-Mo steels have been investigated. An attempt has also been made to modify the microstructure of the steels in order to improve the Charpy properties, by controlling the alloy composition being guided by thermodynamic calculations of phase equilibria. Coarse rod type or agglomerated spherical type cementite particles in inter-lath region were considered to be mostly detrimental to Charpy impact properties. By reducing the precipitation of cementite through decreasing carbon content and/or by substituting it into fine M 2C carbides through increasing the molybdenum content, DBTT could be lowered significantly. Further decrease of DBTT could be achieved by substituting part of manganese content by nickel. Yield strength of tested alloys could be maintained at the level of a reference 0.2 wt% carbon alloy in spite of the significant reduction in carbon content, mainly by the increase in the precipitation of fine M 2C type carbides with increased molybdenum content.

  2. The Charpy impact properties of martensitic 10.6% Cr steel (MANET-1) before and after neutron exposure

    SciTech Connect

    Rieth, M.; Dafferner, B.; Rohrig, H.D.

    1994-12-31

    The MANET-I martensitic 10.6% Cr type of steel was developed as a potential structural material for the first wall and the blanket of a fusion device within the framework of the Nuclear Fusion Project. An extensive irradiation program (FRUST/SIENA) was elaborated to study the influence of radiation upon the Charpy impact characteristics. In addition to unirradiated reference specimens, 87 irradiated subsize Charpy specimens (3 x 4 x 27 mm{sup 3}) were examined under eight different heat treatments at irradiation temperatures between 287{degrees}C and 475{degrees}C and exposure doses of 5 dpa to 15 dpa. On the basis of the numerous test results and their interpretation it is possible to describe radiation induced material embrittlement, and, consequently, the deterioration of the Charpy impact properties. The description is limited, on the one hand, by the variations in the test results and, on the other hand, by the gaps in the test matrix. Therefore, additional investigations, especially in the low irradiation temperature and low dose regimes will be the subject of further ongoing work.

  3. A Method to Estimate the Optimum Temperature for the Cryo-Shattering Separation Using a Charpy Impact Tester

    NASA Astrophysics Data System (ADS)

    Hagura, Yoshio; Watanabe, Hisahiko

    A cryo-shattering separation is a recently developed separation method which is applied to collect low-fat meat from fatty fish. This separation method needs to be operated at the optimum temperature for the cryo-shattering. Determining on optimum temperature needs much works and costs. In this study,an easy method to estimate the optimum temperature for cryo-shattering was proposed using a Charpy impact tester. Four kinds of characteristic temperatures observed through impact tests were used to construct a fracture-temperature-map. By use of the map,the optimum temperature for cryo-shattering was obtained without shattering/sieving experiments.

  4. Effects of thermal aging on fracture toughness and charpy-impact strength of stainless steel pipe welds.

    SciTech Connect

    Gavenda, D. J.; Michaud, W. F.; Galvin, T. M.; Burke, W. F.; Chopra, O. K.; Energy Technology

    1996-06-05

    The degradation of fracture toughness, tensile, and Charpy-impact properties of Type 308 stainless steel (SS) pipe welds due to thermal aging has been characterized at room temperature and 290 C. Thermal aging of SS welds results in moderate decreases in Charpy-impact strength and fracture toughness. For the various welds in this study, upper-shelf energy decreased by 50-80 J/cm{sup 2}. The decrease in fracture toughness J-R curve or JIC is relatively small. Thermal aging had little or no effect on the tensile strength of the welds. Fracture properties of SS welds are controlled by the distribution and morphology of second-phase particles. Failure occurs by the formation and growth of microvoids near hard inclusions; such processes are relatively insensitive to thermal aging. The ferrite phase has little or no effect on the fracture properties of the welds. Differences in fracture resistance of the welds arise from differences in the density and size of inclusions. Mechanical-property data from the present study are consistent with results from other investigations. The existing data have been used to establish minimum expected fracture properties for SS welds.

  5. Effects of thermal aging on fracture toughness and Charpy-impact strength of stainless steel pipe welds

    SciTech Connect

    Gavenda, D.J.; Michaud, W.F.; Galvin, T.M.; Burke, W.F.; Chopra, O.K.

    1996-05-01

    Degradation of fracture toughness, tensile, and Charpy-impact properties of Type 304 and 304/308 SS pipe welds due to thermal aging was studied at room temperature and 290 C. Thermal aging of SS welds results in moderate decreases in charpy-impact strength and fracture toughness. Upper-shelf energy decreased by 50-80 J/cm{sup 2}. Decrease in fracture toughness J-R curve or J{sub IC} is relatively small. Thermal aging had no or little effect on tensile strength of the welds. Fracture properties of SS welds are controlled by the distribution and morphology of second-phase particles. Failure occurs by formation and growth of microvoids near hard inclusions; such processes are relatively insensitive to thermal aging. The ferrite phase has little or no effect on fracture properties of the welds. Differences in fracture resistance of the welds arise from differences in the density and size of inclusions. Mechanical-property data from the present study are consistent with results from other investigations. The existing data have been used to establish minimum expected fracture properties for SS welds.

  6. Low-energy charpy impact of interleaved CF/EP laminates

    NASA Astrophysics Data System (ADS)

    Yuan, Q.; Friedrich, K.; Karger-Kocsis, J.

    1995-03-01

    Carbon fiber (CF) reinforced epoxy (CF/EP) laminates laid up in different ways (cross-ply and quasi-isotropic) with and without various adhesive interlayers (A) were studied under three-point bending using instrumented low-energy impact at single and multiple bounces. Interleaves were a modified EP resin on polyester fabric, a modified EP resin, and a polyethersulphone (PES) film. The impact response depends strongly on whether the CFs are oriented longitudinally (L) or transversely (T) to the hammer edge in the outer bounced ply. The threshold incident energy ( E in,th) associated with severe damage to the laminates was much lower with the longitudinal outer ply. The impact fatigue response of the transverse cross-ply (TCP) and quasi-isotropic (TQI) composite beams showed that stiffness degradation starts at a certain a threshold number of impact (NOI) and follows a logarithmic decay as a function of NOI. This is in close analogy to fatigue tests under usual conditions. Deterioration in stiffness can be assigned to the relative change in the secant slope ( E max/ x max) of the load-displacement ( F-x) traces. The related load-time ( F-t) traces flatten due to impact fatigue so that their load maximum ( F max) shifts toward higher contact time. The efficiency of the interleaving was assessed in both single (at E in,th≈3 J) and repeated impact (at E in=1 J). The first technique allowed us to differentiate between the various interleaves, whereas the latter contributed to finding the optimum stacking and position of the interleaves.

  7. Effect of mechanical alloying atmosphere on the microstructure and Charpy impact properties of an ODS ferritic steel

    NASA Astrophysics Data System (ADS)

    Oksiuta, Z.; Baluc, N.

    2009-04-01

    Two types of oxide dispersion strengthened (ODS) ferritic steels, with the composition of Fe-14Cr-2W-0.3Ti-0.3Y 2O 3 (in weight percent), have been produced by mechanically alloying elemental powders of Fe, Cr, W, and Ti with Y 2O 3 particles either in argon atmosphere or in hydrogen atmosphere, degassing at various temperatures, and compacting the mechanically alloyed powders by hot isostatic pressing. It was found in particular that mechanical alloying in hydrogen yields a significant reduction in oxygen content in the materials, a lower dislocation density, and a strong improvement in the fast fracture properties of the ODS ferritic steels, as measured by Charpy impact tests.

  8. Effects of Mo, Cr, and V Additions on Tensile and Charpy Impact Properties of API X80 Pipeline Steels

    NASA Astrophysics Data System (ADS)

    Han, Seung Youb; Shin, Sang Yong; Seo, Chang-Hyo; Lee, Hakcheol; Bae, Jin-Ho; Kim, Kisoo; Lee, Sunghak; Kim, Nack J.

    2009-08-01

    In this study, four API X80 pipeline steels were fabricated by varying Mo, Cr, and V additions, and their microstructures and crystallographic orientations were analyzed to investigate the effects of their alloying compositions on tensile properties and Charpy impact properties. Because additions of Mo and V promoted the formation of fine acicular ferrite (AF) and granular bainite (GB) while prohibiting the formation of coarse GB, they increased the strength and upper-shelf energy (USE) and decreased the energy transition temperature (ETT). The addition of Cr promoted the formation of coarse GB and hard secondary phases, thereby leading to an increased effective grain size, ETT, and strength, and a decreased USE. The addition of V resulted in a higher strength, a higher USE, a smaller effective grain size, and a lower ETT, because it promoted the formation of fine and homogeneous of AF and GB. The steel that contains 0.3 wt pct Mo and 0.06 wt pct V without Cr had the highest USE and the lowest ETT, because its microstructure was composed of fine AF and GB while its maintained excellent tensile properties.

  9. Effect of Local Crystallographic Texture on the Fissure Formation During Charpy Impact Testing of Low-Carbon Steel

    NASA Astrophysics Data System (ADS)

    Ghosh, Abhijit; Patra, Sudipta; Chatterjee, Arya; Chakrabarti, Debalay

    2016-06-01

    The severity of the formation of fissures (also known as splitting or delamination) on the fracture surface of Charpy impact-tested samples of a low-carbon steel has been found to increase with the decrease in finish rolling temperature [1093 K to 923 K (820 °C to 650 °C)]. Combined scanning electron microscopy and electron back-scattered diffraction study revealed that crystallographic texture was the prime factor responsible for the fissure formation. Through-thickness texture band composed of cube [Normal Direction (ND)║<001>] and gamma [ND║<111>] orientations developed during the inter-critical rolling treatment. Strain incompatibility between these two texture bands causes fissure cracking on the main fracture plane. A new approach based on the angle between {001} planes of neighboring crystals has been employed in order to estimate the `effective grain size,' which is used to determine the cleavage fracture stress on different planes of a sample. The severity of fissure formation was found to be directly related to the difference in cleavage fracture stress between the `main fracture plane' and `fissure plane.' Clustering of ferrite grains having cube texture promoted the fissure crack propagation along the transverse `fissure plane,' by increasing the `effective grain size' and decreasing the cleavage fracture stress on that plane.

  10. Effect of low temperatures on charpy impact toughness of austempered ductile irons

    NASA Astrophysics Data System (ADS)

    Riabov, Mikhail V.; Lerner, Yury S.; Fahmy, Mohammed F.

    2002-10-01

    Impact properties of standard American Society for Testing Materials (ASTM) grades of austempered ductile iron (ADI) were evaluated at subzero temperatures in unnotched and V-notched conditions and compared with ferritic and pearlitic grades of ductile irons (DIs). It was determined that there is a decrease in impact toughness for all ADI grades when there is a decrease in content of retained austenite and a decrease in test temperature, from room temperature (RT) to -60 °C. However, the difference in impact toughness values was not so noticeable for low retained austenite containing grade 5 ADI at both room and subzero temperatures as it was for ADI grade 1. Furthermore, the difference in impact toughness values of V-notched specimens of ADI grades 1 and 5 tested at -40 °C was minimal. The impact behaviors of ADI grade 5 and ferritic DI were found to be more stable than those of ADI grades 1, 2, 3, and 4 and pearlitic DI when the testing temperature was decreased. The impact toughness of ferritic DI was higher than that of ADI grades 1 and 2 at both -40 °C and -60 °C. The impact properties of ADI grades 4 and 5 were found to be higher than that of pearlitic DI at both -40 °C and -60 °C. The scanning electron microscopy (SEM) study of fracture surfaces revealed mixed ductile and quasicleavage rupture morphology types in all ADI samples tested at both -40 °C and -60 °C. With decreasing content of retained austenite and ductility, the number of quasicleavage facets increased from ADI grade 1-5. It was also found that fracture morphology of ADI did not experience significant changes when the testing temperature decreased. Evaluation of the bending angle was used to support impact-testing data. Designers and users of ADI castings may use the data developed in this research as a reference.

  11. Charpy impact test results for low activation ferritic alloys irradiated to 30 dpa

    SciTech Connect

    Schubert, L.E.; Hamilton, M.L.; Gelles, D.S.

    1996-04-01

    Miniature specimens of six low activation ferritic alloys have been impact field tested following irradiation at 370{degrees}C to 30 dpa. Comparison of the results with those of control specimens and specimens irradiated to 10 dpa indicates that degradation in the impact behavior appears to have saturated by {approx}10 dpa in at least four of these alloys. The 7.5Cr-2W alloy referred to as GA3X appears most promising for further consideration as a candidate structural material in fusion reactor applications, although the 9Cr-1V alloy may also warrant further investigation.

  12. Effects of Oxides on Tensile and Charpy Impact Properties and Fracture Toughness in Heat Affected Zones of Oxide-Containing API X80 Linepipe Steels

    NASA Astrophysics Data System (ADS)

    Sung, Hyo Kyung; Sohn, Seok Su; Shin, Sang Yong; Oh, Kyung Shik; Lee, Sunghak

    2014-06-01

    This study is concerned with effects of complex oxides on acicular ferrite (AF) formation, tensile and Charpy impact properties, and fracture toughness in heat affected zones (HAZs) of oxide-containing API X80 linepipe steels. Three steels were fabricated by adding Mg and O2 to form oxides, and various HAZ microstructures were obtained by conducting HAZ simulation tests under different heat inputs. The no. of oxides increased with increasing amount of Mg and O2, while the volume fraction of AF present in the steel HAZs increased with increasing the no. of oxides. The strengths of the HAZ specimens were generally higher than those of the base metals because of the formation of hard microstructures of bainitic ferrite and granular bainite. When the total Charpy absorbed energy was divided into the fracture initiation and propagation energies, the fracture initiation energy was maintained constant at about 75 J at room temperature, irrespective of volume fraction of AF. The fracture propagation energy rapidly increased from 75 to 150 J and saturated when the volume fraction of AF exceeded 30 pct. At 253 K (-20 °C), the total absorbed energy increased with increasing volume fraction of AF, as the cleavage fracture was changed to the ductile fracture when the volume fraction of AF exceeded 45 pct. Thus, 45 vol pct of AF at least was needed to improve the Charpy impact energy, which could be achieved by forming a no. of oxides. The fracture toughness increased with increasing the no. of oxides because of the increased volume fraction of AF formed around oxides. The fracture toughness did not show a visible correlation with the Charpy absorbed energy at room temperature, because toughness properties obtained from these two toughness testing methods had different significations in view of fracture mechanics.

  13. Effects of Microstructure on Tensile, Charpy Impact, and Crack Tip Opening Displacement Properties of Two API X80 Pipeline Steels

    NASA Astrophysics Data System (ADS)

    Shin, Sang Yong

    2013-06-01

    The effects of microstructure on tensile, Charpy impact, and crack tip opening displacement (CTOD) properties of two API X80 pipeline steels were investigated in this study. Two API X80 pipeline steels consisting of acicular ferrite and granular bainite, and a small amount of hard phases such as martensite and secondary phases have elongated grains along the rolling direction, so that they show different mechanical properties as the specimens' directions change. The 90 deg specimens have high tensile strength due to the low stress concentration on the fine hard phases and the high loads for the deformation of the elongated grains. In contrast, the 30 deg specimens have less elongated grains and larger hard phases such as martensite, with the size of about 3 μm, than the 90 deg specimens. Hence, the 30 deg specimens have low tensile strength because of the high stress concentration on the large hard phases and the low loads to deform grains. In the 90 deg specimen, brittle crack propagation surfaces are even since cracks propagate in a straight line along the elongated grain structure. In the 30 deg specimen, however, brittle crack propagation surfaces are uneven, and secondary cracks are observed, because of the zigzag brittle crack propagation path. In the CTOD properties, the 90 deg specimens have maximum forces of higher magnitude than the 30 deg specimens, because of the elongated grain structure. However, CTODs of the 90 deg specimens are lower than those of the 30 deg specimens because of the low plastic deformation areas by the elongated grains in the 90 deg specimens.

  14. Impact dynamics instrumentation

    NASA Astrophysics Data System (ADS)

    McCormck, R. F.

    1986-01-01

    One of the tasks specified in the NASA Langley controlled impact demonstration (CID) work package was to furnish dynamic instrumentation sensors. The types of instrumentation sensors required were accelerometers for aircraft structural loads measurements, seat belt load cells to measure anthropomorphic dummy responses to the aircraft impact, and strain gage bending bridges to measure the aircraft fuselage and wing bending during impact. The objective in the selection of dynamic instrumentation for the CID was to provide 352 of the highest quality transducers and remain within budget allocation. The transducers that were selected for the CID evaluation process were each subjected to rigorous laboratory acceptance tests and to aircraft fuselage section drop tests at the LaRC Impact Dynamics Research Facility. Data compiled from this series of tests showed the selected transducers to be best suited for the CID mission requirement. The transducers installation technique on the airframe proved successful. The transducer quality assurance was guaranteed through rigorous acceptance testing. Data acquired was 97.0%.

  15. A Repeated Impact Method and Instrument to Evaluate the Impact Fatigue Property of Drillpipe

    NASA Astrophysics Data System (ADS)

    Lin, Yuanhua; Li, Qiang; Sun, Yongxing; Zhu, Hongjun; Zhou, Ying; Xie, Juan; Shi, Taihe

    2013-04-01

    It is well known that drillpipe failures are a pendent problem in drilling engineering. Most of drillpipe failures are low amplitude-repeated impact fatigue failures. The traditional method is using Charpy impact test to describe the fracture property of drillpipe, but it cannot veritably characterize the impact fatigue property of drillpipe under low amplitude-repeated impact. Based on the Charpy impact and other methods, a repeated impact method and instrument have been proposed to simulate the low amplitude-repeated impact of downhole conditions for drillpipe. Then, a series of tests have been performed using this instrument. Test results demonstrate the drillpipe upset transition area nonhomogeneity is more severe than drillpipe body, which is the key factor that leads to washout and fracture frequently of it. As the one time impact energy increases, the repeated impact times decrease exponentially, therefore, the rotational speed has a great effect on the fatigue life of drillpipe, and it is vital to select a suitable rotational speed for drilling jobs. In addition, based on SEM fractographs we found that the fracture surface of repeated impact is similar to the fatigue fracture, and there are many low cycle fatigue characteristic features on fracture surface that reveal very good agreement with the features of drillpipe fatigue failures in the field.

  16. Effects of Cooling Conditions on Microstructure, Tensile Properties, and Charpy Impact Toughness of Low-Carbon High-Strength Bainitic Steels

    NASA Astrophysics Data System (ADS)

    Sung, Hyo Kyung; Shin, Sang Yong; Hwang, Byoungchul; Lee, Chang Gil; Lee, Sunghak

    2013-01-01

    In this study, four low-carbon high-strength bainitic steel specimens were fabricated by varying finish cooling temperatures and cooling rates, and their tensile and Charpy impact properties were investigated. All the bainitic steel specimens consisted of acicular ferrite, granular bainite, bainitic ferrite, and martensite-austenite constituents. The specimens fabricated with higher finish cooling temperature had a lower volume fraction of martensite-austenite constituent than the specimens fabricated with lower finish cooling temperature. The fast-cooled specimens had twice the volume fraction of bainitic ferrite and consequently higher yield and tensile strengths than the slow-cooled specimens. The energy transition temperature tended to increase with increasing effective grain size or with increasing volume fraction of granular bainite. The fast-cooled specimen fabricated with high finish cooling temperature and fast cooling rate showed the lowest energy transition temperature among the four specimens because of the lowest content of coarse granular bainite. These findings indicated that Charpy impact properties as well as strength could be improved by suppressing the formation of granular bainite, despite the presence of some hard microstructural constituents such as bainitic ferrite and martensite-austenite.

  17. Influence of thermal conditioning media on Charpy specimen test temperature

    SciTech Connect

    Nanstad, R.K.; Swain, R.L.; Berggren, R.G.

    1989-01-01

    The Charpy V-notch (CVN) impact test is used extensively for determining the toughness of structural materials. Research programs in many technologies concerned with structural integrity perform such testing to obtain Charpy energy vs temperature curves. American Society for Testing and Materials Method E 23 includes rather strict requirements regarding determination and control of specimen test temperature. It specifies minimum soaking times dependent on the use of liquids or gases as the medium for thermally conditioning the specimen. The method also requires that impact of the specimen occur within 5 s removal from the conditioning medium. It does not, however, provide guidance regarding choice of conditioning media. This investigation was primarily conducted to investigate the changes in specimen temperature which occur when water is used for thermal conditioning. A standard CVN impact specimen of low-alloy steel was instrumented with surface-mounted and embedded thermocouples. Dependent on the media used, the specimen was heated or cooled to selected temperatures in the range {minus}100 to 100{degree}C using cold nitrogen gas, heated air, acetone and dry ice, methanol and dry ice, heated oil, or heated water. After temperature stabilization, the specimen was removed from the conditioning medium while the temperatures were recorded four times per second from all thermocouples using a data acquisition system and a computer. The results show that evaporative cooling causes significant changes in the specimen temperatures when water is used for conditioning. Conditioning in the other media did not result in such significant changes. The results demonstrate that, even within the guidelines of E 23, significant test temperature changes can occur which may substantially affect the Charpy impact test results if water is used for temperature conditioning. 7 refs., 11 figs.

  18. Effects of oxidation on the impact energy of Hastelloy S and Hastelloy C-4 Charpy V-notch specimens heated in air at 600 to 800

    SciTech Connect

    Fullam, H.T.

    1981-01-01

    The /sup 90/SrF/sub 2/ heat source being developed at PNL utilizes a Hastelloy S or Hastelloy C-4 outer capsule having a 0.5-in.-thick wall to contain the Hastelloy C-276 inner capsule. The primary objective of the study was to demonstrate that the air oxidation of the outer capsule that could occur during heat-source service would not degrade the ductility and Charpy impact strength of the capsule below the licensing requirements given in Section 1.1. The /sup 90/SrF/sub 2/ heat source under development is intended for general-purpose use. Compatibility considerations limit the interface temperature between the /sup 90/SrF/sub 2/ and Hastelloy C-276 inner capsule to a maximum of 800/sup 0/C. The outer capsule surface temperature will be somewhat less than 800/sup 0/C, and depending on the service, may be substantially lower. The oxidation tests were therefore carried out at 600/sup 0/ to 800/sup 0/C for exposures up to 10,000h to cover the range of temperature the outer capsule might expect to encounter in service. The results showed that the oxidation of Hastelloy S and Hastelloy C-4 in air at 600/sup 0/ to 800/sup 0/C is very slow, and both alloys form adherent oxide layers that serve to protect the underlying metal. Subsurface attack of Hastelloy S and Hastelloy C-4 due to oxidation was greater than expected, considering the slow oxidation rates of the two alloys at 600/sup 0/ to 800/sup 0/C. Estimates of subsurface attack, determined from micrographs of the oxidized specimens, showed erratic results and it was impossible to assign any type of rate equation to the subsurface attack. A conservative estimate of long-term effects can be made using a linear extrapolation of the test results. There were no significant differences between the room-temperature Charpy impact energy of Hastelloy S and Hastelloy C-4 specimens oxidized in air at 600/sup 0/ to 800/sup 0/C and control specimens heated in vacuum.

  19. Compound Charpy specimens by adhesive joining

    NASA Astrophysics Data System (ADS)

    Ghoneim, M. M.; Hammad, F. H.; Pachur, D.; Britz, L.

    1992-03-01

    Compound (reconstituted) Charpy specimens were manufactured by an adhesive joining method in which each half of a previously tested specimen formed the central section of a new testpiece. 29 adhesives were screened to select the most suitable. Compound specimens were precracked and used as minature fracture mechanics specimens and tested in both 3-point static bending and impact. The results are in good agreement with those of conventional specimens. Recommendations for the most appropriate commercial adhesive for hot cell operations are given.

  20. Charpy impact test results of four low activation ferritic alloys irradiated at 370{degrees}C to 15 DPA

    SciTech Connect

    Schubert, L.E.; Hamilton, M.L.; Gelles, D.S.

    1996-10-01

    Miniature CVN specimens of four low activation ferritic alloys have been impact tested following irradiation at 370{degrees}C to 15 dpa. Comparison of the results with those of control specimens indicates that degradation in the impact behavior occurs in each of these four alloys. The 9Cr-2W alloy referred to as GA3X and the similar alloy F82H with 7.8Cr-2W appear most promising for further consideration as candidate structural materials in fusion energy system applications. These two alloys exhibit a small DBTT shift to higher temperatures but show increased absorbed energy on the upper shelf.

  1. The Charpy impact behavior of Fe{sub 3}Al and Fe{sub 3}Al-20 at % Mn alloys

    SciTech Connect

    Liu, J.N.; Yan, W.; Ma, J.L.; Wu, K.H.

    1997-12-31

    A series of experiments were conducted to investigate the impact fracture behavior of Fe{sub 3}Al and Fe{sub 3}Al-20 Mn alloys. The results of this study indicated that: (i) The addition of Mn introduces an ordered L1{sub 2}-type phase in the Fe{sub 3}Al-based alloys. On the other hand, the addition of Mn decreases the order parameter of the DO{sub 3} {alpha} phase. (ii) The total-impact energy of an Fe{sub 3}Al alloy increases with the temperature at the low-temperature range (<600 C), then drops around 700 C, and finally increases again as the temperature further elevates. (iii) The trend of the variation of the impact energy of Fe{sub 3}Al-20 at % Mn alloy with temperature is the same as that of the Fe{sub 3}Al alloy. (iv) And the addition of Mn significantly improves the impact energy of the Fe{sub 3}Al-based alloy, and changes the variation of the crack-growth energy with the testing temperature when the temperature is above 700 C.

  2. Effects of Rolling and Cooling Conditions on Microstructure and Tensile and Charpy Impact Properties of Ultra-Low-Carbon High-Strength Bainitic Steels

    NASA Astrophysics Data System (ADS)

    Sung, Hyo Kyung; Shin, Sang Yong; Hwang, Byoungchul; Lee, Chang Gil; Kim, Nack J.; Lee, Sunghak

    2011-07-01

    Six ultra-low-carbon high-strength bainitic steel plates were fabricated by controlling rolling and cooling conditions, and effects of bainitic microstructure on tensile and Charpy impact properties were investigated. The microstructural evolution was more critically affected by start cooling temperature and cooling rate than by finish rolling temperature. Bainitic microstructures such as granular bainites (GBs) and bainitic ferrites (BFs) were well developed as the start cooling temperature decreased or the cooling rate increased. When the steels cooled from 973 K or 873 K (700 °C or 600 °C) were compared under the same cooling rate of 10 K/s (10 °C/s), the steels cooled from 973 K (700 °C) consisted mainly of coarse GBs, while the steels cooled from 873 K (600 °C) contained a considerable amount of BFs having high strength, thereby resulting in the higher strength but the lower ductility and upper shelf energy (USE). When the steels cooled from 673 K (400 °C) at a cooling rate of 10 K/s (10 °C/s) or 0.1 K/s (0.1 °C/s) were compared under the same start cooling temperature of 873 K (600 °C), the fast cooled specimens were composed mainly of coarse GBs or BFs, while the slowly cooled specimens were composed mainly of acicular ferrites (AFs). Since AFs had small effective grain size and contained secondary phases finely distributed at grain boundaries, the slowly cooled specimens had a good combination of strength, ductility, and USE, together with very low energy transition temperature (ETT).

  3. Further Charpy impact test results of low activation ferritic alloys, irradiated at 430{degrees}C to 67 dpa

    SciTech Connect

    Schubert, L.E.; Hamilton, M.L.; Gelles, D.S.

    1997-04-01

    Miniature CVN specimens of four ferritic alloys, GA3X, F82H, GA4X and HT9, have been impact tested following irradiation at 430{degrees}C to 67 dpa. Comparison of the results with those of the previously tested lower dose irradiation condition indicates that the GA3X and F82H alloys, two primary candidate low activation alloys, exhibit virtually identical behavior following irradiation at 430{degrees}C to {approximately}67 dpa and at 370{degrees}C to {approximately}15 dpa. Very little shift is observed in either DBTT or USE relative to the unirradiated condition. The shifts in DBTT and USE observed in both GA4X and HT9 were smaller after irradiation at 430{degrees}C to {approximately}67 dpa than after irradiation at 370{degrees}C to {approximately}15 dpa.

  4. A Microstructural Study on the Observed Differences in Charpy Impact Behavior Between Hot Isostatically Pressed and Forged 304L and 316L Austenitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Cooper, Adam J.; Cooper, Norman I.; Bell, Andrew; Dhers, Jean; Sherry, Andrew H.

    2015-11-01

    With near-net shape technology becoming a more desirable route toward component manufacture due to its ability to reduce machining time and associated costs, it is important to demonstrate that components fabricated via Hot Isostatic Pressing (HIP) are able to perform to similar standards as those set by equivalent forged materials. This paper describes the results of a series of Charpy tests from HIP'd and forged 304L and 316L austenitic stainless steel, and assesses the differences in toughness values observed. The pre-test and post-test microstructures were examined to develop an understanding of the underlying reasons for the differences observed. The as-received microstructure of HIP'd material was found to contain micro-pores, which was not observed in the forged material. In tested specimens, martensite was detectable within close proximity to the fracture surface of Charpy specimens tested at 77 K (-196 °C), and not detected in locations remote from the fracture surface, nor was martensite observed in specimens tested at ambient temperatures. The results suggest that the observed changes in the Charpy toughness are most likely to arise due to differences in as-received microstructures of HIP'd vs forged stainless steel.

  5. Preliminary results from Charpy impact testing of irradiated JPDR weld metal and commissioning of a facility for machining of irradiated materials

    SciTech Connect

    Iskander, S.K.; Hutton, J.T.; Creech, L.E.; Nanstad, R.K.; Manneschmidt, E.T.; Rosseel, T.M.; Bishop, P.S.

    1999-09-01

    Forty two full-size Charpy specimens were machined from eight trepans that originated from the Japan Power Demonstration Reactor (JPDR). They were also successfully tested and the preliminary results are presented in this report. The trends appear to be reasonable with respect to the location of the specimens with regards to whether they originated from the beltline or the core regions of the vessel, and also whether they were from the inside or outside regions of the vessel wall. A short synopsis regarding commissioning of the facility to machine irradiated materials is also provided.

  6. Results of charpy V-notch impact testing of structural steel specimens irradiated at {approximately}30{degrees}C to 1 x 10{sup 16} neutrons/cm{sup 2} in a commercial reactor cavity

    SciTech Connect

    Iskander, S.K.; Stoller, R.E.

    1997-04-01

    A capsule containing Charpy V-notch (CVN) and mini-tensile specimens was irradiated at {approximately} 30{degrees}C ({approximately} 85{degrees}F) in the cavity of a commercial nuclear power plant to a fluence of 1 x 10{sup 16} neutrons/cm{sup 2} (> 1MeV). The capsule included six CVN impact specimens of archival High Flux Isotope Reactor A212 grade B ferritic steel and five CVN impact specimens of a well-studied A36 structural steel. This irradiation was part of the ongoing study of neutron-induced damage effects at the low temperature and flux experienced by reactor supports. The plant operators shut down the plant before the planned exposure was reached. The exposure of these specimens produced no significant irradiation-induced embrittlement. Of interest were the data on unirradiated specimens in the L-T orientation machined from a single plate of A36 structural steel, which is the same specification for the structural steel used in some reactor supports. The average CVN energy of five unirradiated specimens obtained from one region of the plate and tested at room temperature was {approximately} 99 J, while the energy of 11 unirradiated specimens from other locations of the same plate was 45 J, a difference of {approximately} 220%. The CVN impact energies for all 18 specimens ranged from a low of 32 J to a high of 111 J. Moreover, it appears that the University of Kansas CVN impact energy data of the unirradiated specimens at the 100-J level are shifted toward higher temperatures by about 20 K. The results were an example of the extent of scatter possible in CVN impact testing. Generic values for the CVN impact energy of A36 should be used with caution in critical applications.

  7. Failure mechanics of fiber composite notched charpy specimens. [stress analysis

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.

    1976-01-01

    A finite element stress analysis was performed to determine the stress variation in the vicinity of the notch and far field of fiber composites Charpy specimens (ASTM Standard). NASTRAN was used for the finite element analysis assuming linear behavior and equivalent static load. The unidirectional composites investigated ranged from Thornel 75 Epoxy to S-Glass/Epoxy with the fiber direction parallel to the long dimension of the specimen. The results indicate a biaxial stress state exists in (1) the notch vicinity which is dominated by transverse tensile and interlaminar shear and (2) near the load application point which is dominated by transverse compression and interlaminar shear. The results also lead to the postulation of hypotheses for the predominant failure modes, the fracture initiation, and the fracture process. Finally, the results indicate that the notched Charpy test specimen is not suitable for assessing the impact resistance of nonmetallic fiber composites directly.

  8. Instrumented impact properties of zircaloy-oxygen and zircaloy-hydrogen alloys

    SciTech Connect

    Garde, A.M.; Kassner, T.F.

    1980-04-01

    Instrumented-impact tests were performed on subsize Charpy speciments of Zircaloy-2 and -4 with up to approx. 1.3 wt % oxygen and approx. 2500 wt ppM hydrogen at temperatures between 373 and 823/sup 0/K. Self-consistent criteria for the ductile-to-brittle transition, based upon a total absorbed energy of approx. 1.3 x 10/sup 4/ J/m/sup 2/, a dynamic fracture toughness of approx. 10 MPa.m/sup 1/2/, and a ductility index of approx. 0, were established relative to the temperature and oxygen concentration of the transformed BETA-phase material. The effect of hydrogen concentration and hydride morphology, produced by cooling Zircaloy-2 specimens through the temperature range of the BETA ..-->.. ..cap alpha..' = hydride phase transformation at approx. 0.3 and 3 K/s, on the impact properties was determined at temperatures between 373 and 673 K. On an atom fraction basis, oxygen has a greater effect than hydrogen on the impact properties of Zircaloy at temperatures between approx. 400 and 600 K. 34 figures.

  9. Invited Article: Deep Impact instrument calibration.

    PubMed

    Klaasen, Kenneth P; A'Hearn, Michael F; Baca, Michael; Delamere, Alan; Desnoyer, Mark; Farnham, Tony; Groussin, Olivier; Hampton, Donald; Ipatov, Sergei; Li, Jianyang; Lisse, Carey; Mastrodemos, Nickolaos; McLaughlin, Stephanie; Sunshine, Jessica; Thomas, Peter; Wellnitz, Dennis

    2008-09-01

    Calibration of NASA's Deep Impact spacecraft instruments allows reliable scientific interpretation of the images and spectra returned from comet Tempel 1. Calibrations of the four onboard remote sensing imaging instruments have been performed in the areas of geometric calibration, spatial resolution, spectral resolution, and radiometric response. Error sources such as noise (random, coherent, encoding, data compression), detector readout artifacts, scattered light, and radiation interactions have been quantified. The point spread functions (PSFs) of the medium resolution instrument and its twin impactor targeting sensor are near the theoretical minimum [ approximately 1.7 pixels full width at half maximum (FWHM)]. However, the high resolution instrument camera was found to be out of focus with a PSF FWHM of approximately 9 pixels. The charge coupled device (CCD) read noise is approximately 1 DN. Electrical cross-talk between the CCD detector quadrants is correctable to <2 DN. The IR spectrometer response nonlinearity is correctable to approximately 1%. Spectrometer read noise is approximately 2 DN. The variation in zero-exposure signal level with time and spectrometer temperature is not fully characterized; currently corrections are good to approximately 10 DN at best. Wavelength mapping onto the detector is known within 1 pixel; spectral lines have a FWHM of approximately 2 pixels. About 1% of the IR detector pixels behave badly and remain uncalibrated. The spectrometer exhibits a faint ghost image from reflection off a beamsplitter. Instrument absolute radiometric calibration accuracies were determined generally to <10% using star imaging. Flat-field calibration reduces pixel-to-pixel response differences to approximately 0.5% for the cameras and <2% for the spectrometer. A standard calibration image processing pipeline is used to produce archival image files for analysis by researchers. PMID:19044397

  10. Identification of neutron irradiation induced strain rate sensitivity change using inverse FEM analysis of Charpy test

    NASA Astrophysics Data System (ADS)

    Haušild, Petr; Materna, Aleš; Kytka, Miloš

    2015-04-01

    A simple methodology how to obtain additional information about the mechanical behaviour of neutron-irradiated WWER 440 reactor pressure vessel steel was developed. Using inverse identification, the instrumented Charpy test data records were compared with the finite element computations in order to estimate the strain rate sensitivity of 15Ch2MFA steel irradiated with different neutron fluences. The results are interpreted in terms of activation volume change.

  11. Impact of instrument response variations on health physics measurements

    SciTech Connect

    Armantrout, G.A.

    1984-10-01

    Uncertainties in estimating the potential health impact of a given radiation exposure include instrument measurement error in determining exposure and difficulty in relating this exposure to an effective dose value. Instrument error can be due to design or manufacturing deficiencies, limitations of the sensing element used, and calibration and maintenance of the instrument. This paper evaluates the errors which can be introduced by design deficiencies and limitations of the sensing element for a wide variety of commonly used survey instruments. The results indicate little difference among sensing element choice for general survey work, with variations among specific instrument designs being the major factor. Ion chamber instruments tend to be the best for all around use, while scintillator-based units should not be used where accurate measurements are required. The need to properly calibrate and maintain an instrument appears to be the most important factor in instrument accuracy. 8 references, 6 tables.

  12. Debris Impact Detection Instrument for Crewed Modules

    NASA Technical Reports Server (NTRS)

    Opiela, J.; Corsaro, R.; Giovanes, F.; Lio, J.-C.

    2012-01-01

    When micrometeoroid or debris impacts occur on a space habitat, crew members need to be quickly informed of the likely extent of damage, and be directed to the impact location for possible repairs. This is especially important because the outer walls of pressurized volumes are often not easily accessible, blocked by racks or cabinets. The goal of the Habitat Particle Impact Monitoring System (HIMS) is to develop a fully automated, end-to-end particle impact detection system for crewed space exploration modules. The HIMS uses multiple passive, thin film piezo-polymer vibration sensors to detect impacts on a surface, and computer processing of the acoustical signals to characterize the impacts. Development and demonstration of the HIMS is proceeding in concert with NASA's Habitat Demonstration Unit (HDU) Project. The HDU Project is designed to develop and test various technologies, configurations, and operational concepts for exploration habitats. This paper describes the HIMS development, initial testing, and HDU integration efforts. Initial tests of the system on the HDU were conducted at NASA s 2010 and 2011 Desert Research and Technologies Studies (Desert-RATS or D-RATS). The HDU lab module, as seen from above, has an open circular floorplan divided into eight wedge-shaped Segments. The side wall of the module -- the surface used for this technology demonstration -- is a hard fiberglass composite covered with a layer of sprayed-on foam insulation. Four sensor locations were assigned near the corners of a rectangular pattern on the wall of one segment of the HDU lab module. The flat, self-adhesive sensors were applied to the module during its initial outfitting. To study the influence of the wall s construction (thickness and materials), three sets of four sensors were installed at different layer depths: on the interior of the module s wall, on the exterior of the same wall, and on the exterior of the foam insulation. The signal produced when a vibration passes

  13. A study of the fracture process and factors that control toughness variability in Charpy V-notch specimens

    NASA Astrophysics Data System (ADS)

    Bouchard, Real

    La presente etude a ete initiee pour developper une comprehension quantitative du processus de rupture avec les facteurs qui controlent la dispersion des mesures de tenacite lorsque des eprouvettes Charpy entaillees en V sont utilisees. Un grand nombre d'essais ont ete realises pour un acier C-Mn: eprouvettes Charpy testees sous impact, eprouvettes Charpy testees en flexion lente, eprouvettes axisymetriques entaillees et sollicitees en traction et essais de tenacite sur eprouvettes prefissurees. Base sur le concept de la statistique de Weibull, l'approche locale developpee par le groupe Beremin a ete utilisee pour decrire la probabilite de rupture par clivage en fonction de la contrainte appliquee aussi bien qu'en fonction de l'energie Charpy obtenue. Le calcul par elements finis a ete realise pour determiner la distribution de la deformation et des contraintes en pointe d'entaille et de fissure. La nouvelle approche introduite decrit bien les resultats experimentaux. Les points d'initiation du clivage ont ete identifies au MEB et par la suite, avec la technique de faisceau d'ions focalise, sectionnes, polis et examines. L'examen de la microstructure sous le point d'initiation revele clairement que le clivage s'initie par un mecanisme d'empilement de dislocations ou les dislocations sont arretees aux joints de grain, aux interfaces de perlite/ferrite ou de perlite qui agissent comme barrieres physiques.

  14. Certification of NIST Room Temperature Low-Energy and High-Energy Charpy Verification Specimens

    PubMed Central

    Lucon, Enrico; McCowan, Chris N.; Santoyo, Ray L.

    2015-01-01

    The possibility for NIST to certify Charpy reference specimens for testing at room temperature (21 °C ± 1 °C) instead of −40 °C was investigated by performing 130 room-temperature tests from five low-energy and four high-energy lots of steel on the three master Charpy machines located in Boulder, CO. The statistical analyses performed show that in most cases the variability of results (i.e., the experimental scatter) is reduced when testing at room temperature. For eight out of the nine lots considered, the observed variability was lower at 21 °C than at −40 °C. The results of this study will allow NIST to satisfy requests for room-temperature Charpy verification specimens that have been received from customers for several years: testing at 21 °C removes from the verification process the operator’s skill in transferring the specimen in a timely fashion from the cooling bath to the impact position, and puts the focus back on the machine performance. For NIST, it also reduces the time and cost for certifying new verification lots. For one of the low-energy lots tested with a C-shaped hammer, we experienced two specimens jamming, which yielded unusually high values of absorbed energy. For both specimens, the signs of jamming were clearly visible. For all the low-energy lots investigated, jamming is slightly more likely to occur at 21 °C than at −40 °C, since at room temperature low-energy samples tend to remain in the test area after impact rather than exiting in the opposite direction of the pendulum swing. In the evaluation of a verification set, any jammed specimen should be removed from the analyses. PMID:26958453

  15. Kinematic analyses of instrumentation cubes in vehicle impact experiments.

    PubMed

    Shin, Jaeho; Untaroiu, Costin D; Kerrigan, Jason R; Forman, Jason L; Crandall, Jeff R

    2008-01-01

    Three-dimensional kinematics of body targets are frequently tracked during vehicle impact tests using instrumented cubes. While the components of linear acceleration and angular velocity are recorded in a cube local coordinate system, transformation to a global coordinate system is required to reconstruct the whole body motions. This paper presents a methodology for local-to-global kinematic transformations using a finite element cube model mounted on heads with local measurements. This methodology was used to reconstruct the head kinematics during occupant and pedestrian impact tests and shown to produce similar displacement, velocity, and acceleration results to those obtained by the Euler parameter method. In addition, the possible measurement errors of the local frame orientation were simulated and the proportional displacements and velocities were observed in simulation outputs: the maximum differences are 6.5 % of a global displacement and 9.1 % of a global velocity at applying a 10 degree rotated measurement error in the initial local frame. PMID:19141896

  16. Controlled Impact Demonstration instrumented test dummies installed in plane

    NASA Technical Reports Server (NTRS)

    1984-01-01

    In this photograph are seen some of dummies in the passenger cabin of the B-720 aircraft. NASA Langley Research Center instrumented a large portion of the aircraft and the dummies for loads in a crashworthiness research program. In 1984 NASA Dryden Flight Research Facility and the Federal Aviation Adimistration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID). The test involved crashing a Boeing 720 aircraft with four JT3C-7 engines burning a mixture of standard fuel with an additive called Anti-misting Kerosene (AMK) designed to supress fire. In a typical aircraft crash, fuel spilled from ruptured fuel tanks forms a fine mist that can be ignited by a number of sources at the crash site. In 1984 the NASA Dryden Flight Research Facility (after 1994 a full-fledged Center again) and the Federal Aviation Administration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID), to test crash a Boeing 720 aircraft using standard fuel with an additive designed to supress fire. The additive, FM-9, a high-molecular-weight long-chain polymer, when blended with Jet-A fuel had demonstrated the capability to inhibit ignition and flame propagation of the released fuel in simulated crash tests. This anti-misting kerosene (AMK) cannot be introduced directly into a gas turbine engine due to several possible problems such as clogging of filters. The AMK must be restored to almost Jet-A before being introduced into the engine for burning. This restoration is called 'degradation' and was accomplished on the B-720 using a device called a 'degrader.' Each of the four Pratt & Whitney JT3C-7 engines had a 'degrader' built and installed by General Electric (GE) to break down and return the AMK to near Jet-A quality. In addition to the AMK research the NASA Langley Research Center was involved in a structural loads measurement experiment, which included having instrumented dummies filling the seats in the

  17. Laboratory Instrumentation: An Exploration of the Impact of Instrumentation on Student Learning

    ERIC Educational Resources Information Center

    Warner, Don L.; Brown, Eric C.; Shadle, Susan E.

    2016-01-01

    Academic programs generally work to make their laboratory curriculum both as instrumentation rich and up to date as possible. However, little is known about the relationship between the use of instrumentation in the curriculum and student learning. As part of our department's ongoing assessment efforts, a project was designed to probe this…

  18. INSTRUMENTAL and OPERATIONAL IMPACTS on SPECTROPHOTOMETER COLOR MEASUREMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Color measurements for the classing of U.S. cottons have been performed on the Uster® High Volume Instrumentation (HVI) instrument for several years. Two color parameters specific to cotton—Rd (reflectance) and +b (yellowness)—are used to express the color of cotton. Since Rd and +b do not readily...

  19. The impact resistance of SiC and other mechanical properties of SiC and Si3N4

    NASA Technical Reports Server (NTRS)

    Bradt, R. C.

    1984-01-01

    Studies focused on the impact and mechanical behavior of SiC and Si3N4 at high temperatures are summarized. Instrumented Charpy impact testing is analyzed by a compliance method and related to strength; slow crack growth is related to processing, and creep is discussed. The transient nature of flaw populations during oxidation under load is emphasized for both SiC and Si3N4.

  20. Impact of Smoke Exposure on Digital Instrumentation and Control

    SciTech Connect

    Tanaka, Tina J.; Nowlen, Steven P.; Korsah, Kofi; Wood, Richard T.; Antonescu, Christina E.

    2003-08-15

    Smoke can cause interruptions and upsets in active electronics. Because nuclear power plants are replacing analog with digital instrumentation and control systems, qualification guidelines for new systems are being reviewed for severe environments such as smoke and electromagnetic interference. Active digital systems, individual components, and active circuits have been exposed to smoke in a program sponsored by the U.S. Nuclear Regulatory Commission. The circuits and systems were all monitored during the smoke exposure, indicating any immediate effects of the smoke. The results of previous smoke exposure studies have been reported in various publications. The major immediate effect of smoke has been to increase leakage currents and to cause momentary upsets and failures in digital systems. This paper presents new results from conformal coatings, memory chips, and hard drive tests.The best conformal coatings were found to be polyurethane, parylene, and acrylic (when applied by dipping). Conformal coatings can reduce smoke-induced leakage currents and protect against metal loss through corrosion. However conformal coatings are typically flammable, so they do increase material flammability. Some of the low-voltage biased memory chips failed during a combination of high smoke and high humidity. Typically, smoke along with heat and humidity is expected during fire, rather than smoke alone. Thus, due to high sensitivity of digital circuits to heat and humidity, it is hypothesized that the impact of smoke may be secondary.Low-voltage (3.3-V) static random-access memory (SRAMs) were found to be the most vulnerable to smoke. Higher bias voltages decrease the likelihood of failure. Erasable programmable read-only memory (EPROMs) and nonvolatile SRAMs were very smoke tolerant. Failures of the SRAMs occurred when two conditions were present: high density of smoke and high humidity. As the high humidity was present for only part of the test, the failures were intermittent. All

  1. Fractographic examination of reduced activation ferritic/martensitic steel charpy specimens irradiated to 30 dpa at 370{degrees}C

    SciTech Connect

    Gelles, D.S.; Hamilton, M.L.; Schubert, L.E.

    1996-10-01

    Fractographic examinations are reported for a series of reduced activation ferritic/Martensitic steel Charpy impact specimens tested following irradiation to 30 dpa at 370{degrees}C in FFTF. One-third size specimens of six low activation steels developed for potential application as structural materials in fusion reactors were examined. A shift in brittle fracture appearance from cleavage to grain boundary failure was noted with increasing manganese content. The results are interpreted in light of transmutation induced composition changes in a fusion environment.

  2. Impact of new instrumentation on advanced turbine research

    NASA Technical Reports Server (NTRS)

    Graham, R. W.

    1980-01-01

    A description is presented of an orderly test program that progresses from the simplest stationary geometry to the more complex, three dimensional, rotating turbine stage. The instrumentation requirements for this evolution of testing are described. The heat transfer instrumentation is emphasized. Recent progress made in devising new measurement techniques has greatly improved the development and confirmation of more accurate analytical methods for the prediction of turbine performance and heat transfer. However, there remain challenging requirements for novel measurement techniques that could advance the future research to be done in rotating blade rows of turbomachines.

  3. A Review of Instrumented Equipment to Investigate Head Impacts in Sport.

    PubMed

    Patton, Declan A

    2016-01-01

    Contact, collision, and combat sports have more head impacts as compared to noncontact sports; therefore, such sports are uniquely suited to the investigation of head impact biomechanics. Recent advances in technology have enabled the development of instrumented equipment, which can estimate the head impact kinematics of human subjects in vivo. Literature pertaining to head impact measurement devices was reviewed and usage, in terms of validation and field studies, of such devices was discussed. Over the past decade, instrumented equipment has recorded millions of impacts in the laboratory, on the field, in the ring, and on the ice. Instrumented equipment is not without limitations; however, in vivo head impact data is crucial to investigate head injury mechanisms and further the understanding of concussion. PMID:27594780

  4. A Review of Instrumented Equipment to Investigate Head Impacts in Sport

    PubMed Central

    2016-01-01

    Contact, collision, and combat sports have more head impacts as compared to noncontact sports; therefore, such sports are uniquely suited to the investigation of head impact biomechanics. Recent advances in technology have enabled the development of instrumented equipment, which can estimate the head impact kinematics of human subjects in vivo. Literature pertaining to head impact measurement devices was reviewed and usage, in terms of validation and field studies, of such devices was discussed. Over the past decade, instrumented equipment has recorded millions of impacts in the laboratory, on the field, in the ring, and on the ice. Instrumented equipment is not without limitations; however, in vivo head impact data is crucial to investigate head injury mechanisms and further the understanding of concussion. PMID:27594780

  5. Ice Particle Impact on Cloud Water Content Instrumentation

    NASA Technical Reports Server (NTRS)

    Emery, Edward F.; Miller, Dean R.; Plaskon, Stephen R.; Strapp, Walter; Lillie, Lyle

    2004-01-01

    Determining the total amount of water contained in an icing cloud necessitates the measurement of both the liquid droplets and ice particles. One commonly accepted method for measuring cloud water content utilizes a hot wire sensing element, which is maintained at a constant temperature. In this approach, the cloud water content is equated with the power required to keep the sense element at a constant temperature. This method inherently assumes that impinging cloud particles remain on the sensing element surface long enough to be evaporated. In the case of ice particles, this assumption requires that the particles do not bounce off the surface after impact. Recent tests aimed at characterizing ice particle impact on a thermally heated wing section, have raised questions about the validity of this assumption. Ice particles were observed to bounce off the heated wing section a very high percentage of the time. This result could have implications for Total Water Content sensors which are designed to capture ice particles, and thus do not account for bouncing or breakup of ice particles. Based on these results, a test was conducted to investigate ice particle impact on the sensing elements of the following hot-wire cloud water content probes: (1) Nevzorov Total Water Content (TWC)/Liquid Water Content (LWC) probe, (2) Science Engineering Associates TWC probe, and (3) Particle Measuring Systems King probe. Close-up video imaging was used to study ice particle impact on the sensing element of each probe. The measured water content from each probe was also determined for each cloud condition. This paper will present results from this investigation and attempt to evaluate the significance of ice particle impact on hot-wire cloud water content measurements.

  6. Impact of Nuclear Data Uncertainties on Calculated Spent Fuel Nuclide Inventories and Advanced NDA Instrument Response

    SciTech Connect

    Hu, Jianwei; Gauld, Ian C.

    2014-12-01

    The U.S. Department of Energy’s Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) project is nearing the final phase of developing several advanced nondestructive assay (NDA) instruments designed to measure spent nuclear fuel assemblies for the purpose of improving nuclear safeguards. Current efforts are focusing on calibrating several of these instruments with spent fuel assemblies at two international spent fuel facilities. Modelling and simulation is expected to play an important role in predicting nuclide compositions, neutron and gamma source terms, and instrument responses in order to inform the instrument calibration procedures. As part of NGSI-SF project, this work was carried out to assess the impacts of uncertainties in the nuclear data used in the calculations of spent fuel content, radiation emissions and instrument responses. Nuclear data is an essential part of nuclear fuel burnup and decay codes and nuclear transport codes. Such codes are routinely used for analysis of spent fuel and NDA safeguards instruments. Hence, the uncertainties existing in the nuclear data used in these codes affect the accuracies of such analysis. In addition, nuclear data uncertainties represent the limiting (smallest) uncertainties that can be expected from nuclear code predictions, and therefore define the highest attainable accuracy of the NDA instrument. This work studies the impacts of nuclear data uncertainties on calculated spent fuel nuclide inventories and the associated NDA instrument response. Recently developed methods within the SCALE code system are applied in this study. The Californium Interrogation with Prompt Neutron instrument was selected to illustrate the impact of these uncertainties on NDA instrument response.

  7. Impact of Nuclear Data Uncertainties on Calculated Spent Fuel Nuclide Inventories and Advanced NDA Instrument Response

    DOE PAGESBeta

    Hu, Jianwei; Gauld, Ian C.

    2014-12-01

    The U.S. Department of Energy’s Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) project is nearing the final phase of developing several advanced nondestructive assay (NDA) instruments designed to measure spent nuclear fuel assemblies for the purpose of improving nuclear safeguards. Current efforts are focusing on calibrating several of these instruments with spent fuel assemblies at two international spent fuel facilities. Modelling and simulation is expected to play an important role in predicting nuclide compositions, neutron and gamma source terms, and instrument responses in order to inform the instrument calibration procedures. As part of NGSI-SF project, this work was carried outmore » to assess the impacts of uncertainties in the nuclear data used in the calculations of spent fuel content, radiation emissions and instrument responses. Nuclear data is an essential part of nuclear fuel burnup and decay codes and nuclear transport codes. Such codes are routinely used for analysis of spent fuel and NDA safeguards instruments. Hence, the uncertainties existing in the nuclear data used in these codes affect the accuracies of such analysis. In addition, nuclear data uncertainties represent the limiting (smallest) uncertainties that can be expected from nuclear code predictions, and therefore define the highest attainable accuracy of the NDA instrument. This work studies the impacts of nuclear data uncertainties on calculated spent fuel nuclide inventories and the associated NDA instrument response. Recently developed methods within the SCALE code system are applied in this study. The Californium Interrogation with Prompt Neutron instrument was selected to illustrate the impact of these uncertainties on NDA instrument response.« less

  8. Instrumented impact and residual tensile strength testing of eight-ply carbon eopoxy specimens

    NASA Technical Reports Server (NTRS)

    Nettles, A. T.

    1990-01-01

    Instrumented drop weight impact testing was utilized to examine a puncture-type impact on thin carbon-epoxy coupons. Four different material systems with various eight-ply lay-up configurations were tested. Specimens were placed over a 10.3-mm diameter hole and impacted with a smaller tup (4.2-mm diameter) than those used in previous studies. Force-time plots as well as data on absorbed energy and residual tensile strength were gathered and examined. It was found that a critical impact energy level existed for each material tested, at which point tensile strength began to rapidly decrease with increasing impact energy.

  9. Evaluating the effectiveness of impact assessment instruments: Theorising the nature and implications of their political constitution

    SciTech Connect

    Cashmore, Matthew; Richardson, Tim; Hilding-Ryedvik, Tuija; Emmelin, Lars

    2010-11-15

    The central role of impact assessment instruments globally in policy integration initiatives has been cemented in recent years. Associated with this trend, but also reflecting political emphasis on greater accountability in certain policy sectors and a renewed focus on economic competitiveness in Western countries, demand has increased for evidence that these instruments are effective (however defined). Resurgent interest in evaluation has not, however, been accompanied by the conceptual developments required to redress longstanding theoretical problems associated with such activities. In order to sharpen effectiveness evaluation theory for impact assessment instruments this article critically examines the neglected issue of their political constitution. Analytical examples are used to concretely explore the nature and significance of the politicisation of impact assessment. It is argued that raising awareness about the political character of impact assessment instruments, in itself, is a vital step in advancing effectiveness evaluation theory. Broader theoretical lessons on the framing of evaluation research are also drawn from the political analysis. We conclude that, at least within the contemporary research context, learning derived from analysing the meaning and implications of plural interpretations of effectiveness represents the most constructive strategy for advancing impact assessment and policy integration theory.

  10. Assessment of Ductile-to-Brittle Transition Behavior of Localized Microstructural Regions in a Friction-Stir Welded X80 Pipeline Steel with Miniaturized Charpy V-Notch Testing

    NASA Astrophysics Data System (ADS)

    Avila, Julian A.; Lucon, Enrico; Sowards, Jeffrey; Mei, Paulo Roberto; Ramirez, Antonio J.

    2016-04-01

    Friction-stir welding (FSW) is an alternative welding process for pipelines. This technology offers sound welds, good repeatability, and excellent mechanical properties. However, it is of paramount importance to determine the toughness of the welds at low temperatures in order to establish the limits of this technology. Ductile-to-brittle transition curves were generated in the present study by using a small-scale instrumented Charpy machine and miniaturized V-notch specimens (Kleinstprobe, KLST); notches were located in base metal, heat-affected, stirred, and hard zones within a FSW joint of API-5L X80 Pipeline Steel. Specimens were tested at temperatures between 77 K (-196 °C) and 298 K (25 °C). Based on the results obtained, the transition temperatures for the base material and heat-affected zone were below 173 K (-100 °C); conversely, for the stirred and hard zones, it was located around 213 K (-60 °C). Fracture surfaces were characterized and showed a ductile fracture mechanism at high impact energies and a mixture of ductile and brittle mechanisms at low impact energies.

  11. Assessment of Ductile-to-Brittle Transition Behavior of Localized Microstructural Regions in a Friction-Stir Welded X80 Pipeline Steel with Miniaturized Charpy V-Notch Testing

    NASA Astrophysics Data System (ADS)

    Avila, Julian A.; Lucon, Enrico; Sowards, Jeffrey; Mei, Paulo Roberto; Ramirez, Antonio J.

    2016-06-01

    Friction-stir welding (FSW) is an alternative welding process for pipelines. This technology offers sound welds, good repeatability, and excellent mechanical properties. However, it is of paramount importance to determine the toughness of the welds at low temperatures in order to establish the limits of this technology. Ductile-to-brittle transition curves were generated in the present study by using a small-scale instrumented Charpy machine and miniaturized V-notch specimens (Kleinstprobe, KLST); notches were located in base metal, heat-affected, stirred, and hard zones within a FSW joint of API-5L X80 Pipeline Steel. Specimens were tested at temperatures between 77 K (-196 °C) and 298 K (25 °C). Based on the results obtained, the transition temperatures for the base material and heat-affected zone were below 173 K (-100 °C); conversely, for the stirred and hard zones, it was located around 213 K (-60 °C). Fracture surfaces were characterized and showed a ductile fracture mechanism at high impact energies and a mixture of ductile and brittle mechanisms at low impact energies.

  12. Bond strength of pressure sensitive adhesives for CFRP aluminium-alloy hybrid beams under impact loading

    NASA Astrophysics Data System (ADS)

    Sato, C.

    2003-09-01

    This paper discusses the impact absorbing capabilities of CFRP aluminium-alloy hybrid beams bonded with double-coated pressure sensitive adhesive tapes. Two sorts of double-coated adhesive tapes (VHB and SBT, 3M) were used in experiments. The strength and absorbed energy of the beams under impact loading were measured using an instrumented Charpy tester. Using the beams having the different adhesive tapes and the CFRP of different length, the variations of the strength and the absorbed energy were investigated. The beams bonded with VHB showed sufficient strength and absorbed energy. SBT showed also great capability of absorbing impact energy.

  13. The impact of the long-term playing of musical instruments on the stomatognathic system - review.

    PubMed

    Głowacka, Arleta; Matthews-Kozanecka, Maja; Kawala, Maciej; Kawala, Beata

    2014-01-01

    In this article, we have made a review of the influence of playing musical instruments on the formation of malocclusion and TMJ disorders in musicians. Primary attention was paid to the effects of wind and stringed instruments. The aim of the article was the presentation of research and opinions about this problem in the last 25 years. It is reported that long-term and repetitive playing of musical instruments, particularly stringed (violin and viola) and wind instruments can cause dysfunctions of the stomatognathic system. The impact of wind instruments was assessed in terms of the type of mouthpiece. We studied the possibility of repositioning the front teeth and reducing the width of the upper dental arch and overbite. There were also reports on the use of a specific instrument to improve the child's occlusion. Studies have also been performed on the usefulness of relaxation plates in order to improve, and even prevent, dysfunction caused by the constant stress on the same parts of the stomatognathic system. The experiments were mainly based on interviews, dental cast analyses and cephalometric analyses. Additional methods were dynamometer tests and muscle tension palpation. PMID:24596017

  14. Visual analysis of ductility/brittleness of welding fracture points on charpy test specimens using graphical blocks on field programmable gate arrays

    NASA Astrophysics Data System (ADS)

    Tickle, Andrew J.; Camargo-Rodriguez, Anyela; Smith, Jeremy S.

    2008-09-01

    The charpy impact is a technique used to evaluate the toughness of an engineering material that determines the amount of energy absorbed by it during fracture. Initially, measurements were estimated manually and later replaced by a PC version. This study reports the development of the Field Programmable Gate Array (FPGA) portable version. The FPGA based version allows easy analysis of samples without the need of sending them to a lab for analysis. The process, presented here, as the original, is based on measuring the percent of crystal in the test sample after impact, to determine if the material is ductile or brittle. The FPGA version, adapted under the MATLAB Simulink environment, shows a graphical block representation of the charpy impact PC version. An important asset of the FPGA version is its portability, it has to be easily modified and downloaded onto a device to estimate the percent of brittle fracture of the broken Charpy surface. The beauty of the DSP Builder programme is that it allows the model to be compiled to various types of optimised code for any Altera FPGA device. To provide a firm basis for scientific comparison to the new FPGA system, images already analysed via the PC based Java system were also used for testing and comparison purposes. The FPGA system converts the image into an 8 bit grayscale image and analyses it in a 5x5 sampling window. This produces texture features that can be used in a comparison system, similar to the Support Vector Machine (SVM) used in the original. The output is a signal that states the material being tested is brittle or not via an output of '1' for brittle and a '0' for ductile. A detailed pixel by pixel analysis of the various output images is then investigated to state the percentage difference between the PC and FPGA based systems.

  15. Impact of aberrations on the measurement of the solar diameter with the SODISM instrument

    NASA Astrophysics Data System (ADS)

    Riguet, François; Meftah, Mustapha; Pradal, Fabien

    2015-09-01

    PICARD, a Sun observing satellite, has produced more than one million images during its 4-year mission. SODISM is one of three instruments on-board, whose main goal is to measure the solar limb and its spectral dependence from the middle ultraviolet to the near infrared. The very high accuracy (a few milli-arcseconds) needed to measure the solar limb with its spatial and temporal variations makes the instrument very sensitive to small aberrations. In this paper, we will present the impact of various parameters on the solar limb measurement, from simple displacements of mirrors to complex mirror deformations and thermal gradients. A complete scenario has been constructed from these simulations, leading to a model that describes the actual limbs obtained with SODISM. All these simulations will help improving future missions, by assessing the critical parameters affecting the measurement accuracies of such instruments.

  16. Sex Differences and the Impact of Chronic Stress and Recovery on Instrumental Learning

    PubMed Central

    McDowell, Angela L.; Fransen, Kathryn M. H.; Elliott, Kevin S.; Elghouche, Alhasan; Kostylev, Polina V.; O'Dea, Pamela K.; Garraghty, Preston E.

    2015-01-01

    We have previously shown that 21-day chronic restraint stress impacts instrumental learning, but overall few studies have examined sex differences on the impact of stress on learning. We further examined sex differences in response to extended 42-day chronic stress on instrumental learning, as well as recovery from chronic stress. Rats were tested in aversive training tasks with or without prior appetitive experience, and daily body weight data was collected as an index of stress. Relative to control animals, reduced body weight was maintained from day 22 through day 42 across the stress period for males, but not for females. Stressed males had increased response speed and lower learning efficiency during appetitive acquisition and aversive learning. Males overall showed slower escape shaping times and more shock exposure. In contrast, stressed females showed slower appetitive response speeds and higher appetitive and aversive efficiency but overall reduced avoidance rates during acquisition and maintenance for transfer animals and during maintenance for aversive-only animals. These tasks reveal important nuances on the effect of stress on goal-directed behavior and further highlight sexually divergent effects on appetitive versus aversive motivation. Furthermore, these data underscore that systems are temporally impacted by chronic stress in a sexually divergent pattern. PMID:26317113

  17. The Impact of a School Loaner-Instrument Program on the Attitudes and Achievement of Low-Income Music Students

    ERIC Educational Resources Information Center

    Ester, Don; Turner, Kristin

    2009-01-01

    The purpose of this study was to investigate the impact of a public school loaner-instrument program on the attitudes and achievement of low-income students in an urban environment. Socioeconomic Status (SES) and Instrument Status served as independent variables. Participants (N = 245) completed surveys at the beginning and end of the school year,…

  18. Fracture toughness testing of Linde 1092 reactor vessel welds in the transition range using Charpy-sized specimens

    SciTech Connect

    Pavinich, W.A.; Yoon, K.K.; Hour, K.Y.; Hoffman, C.L.

    1999-10-01

    The present reference toughness method for predicting the change in fracture toughness can provide over estimates of these values because of uncertainties in initial RT{sub NDT} and shift correlations. It would be preferable to directly measure fracture toughness. However, until recently, no standard method was available to characterize fracture toughness in the transition range. ASTM E08 has developed a draft standard that shows promise for providing lower bound transition range fracture toughness using the master curve approach. This method has been successfully implemented using 1T compact fracture specimens. Combustion Engineering reactor vessel surveillance programs do not have compact fracture specimens. Therefore, the CE Owners Group developed a program to validate the master curve method for Charpy-sized and reconstituted Charpy-sized specimens for future application on irradiated specimens. This method was validated for Linde 1092 welds using unirradiated Charpy-sized and reconstituted Charpy-sized specimens by comparison of results with those from compact fracture specimens.

  19. Impacted canine extraction by ridge expansion using air scaler surgical instruments: a case report.

    PubMed

    Agabiti, Ivo; Bernardello, Fabio; Nevins, Myron; Wang, Hom-Lay

    2014-01-01

    The presence of an impacted tooth interferes with ideal implant placement. In such cases, atraumatic extraction is recommended in order to avoid difficult and complex bone regeneration procedures. In the present case report, a novel surgical approach to extract a horizontally impacted canine using an edentulous ridge expansion (ERE) technique and air scaler surgical devices is described. A 74-year-old female patient had a maxillary left horizontally impacted canine. The tooth was extracted after elevating a partial-thickness flap and performing an ERE technique using air scaler surgical instruments. The impacted tooth was fragmented through the breach created in the expanded ridge, and the fragments were carefully removed. A suitably sized implant was placed at the time of surgery. The treated site healed without complication. The implant was integrated, successfully restored, and stable after a 3-year follow-up period. This case report demonstrates a novel surgical approach to extract an impacted canine through ridge expansion, using air scaler surgical devices that allow implant placement in an ideal position. PMID:25171039

  20. Monitoring of Refractory Wall recession using high temperature impact echo instrumentation

    SciTech Connect

    University of Dayton

    2004-04-30

    Regression of refractory linings of furnaces occurs due to a variety of mechanisms. The specific mechanism selected for investigation during this program is the regression of refractories which are in direct contact with a liquid corrodant. Examples include the melting of glass, the production of pig iron and steel, and the melting of aluminum. The rates of regression to a wall thickness which requires reline or extensive reconstruction vary widely, from less than a year to over ten years depending on the specific service environment. This program investigated the feasibility of measuring refractory wall thickness with an impact-echo method while at operating temperature (wall temperatures exceeding 500 C). The impact-echo method uses the impact of a small sphere with the surface of the test object to send a stress wave into the object. In a plate-like structure, the stress wave reflects back to the front surface, reverberating in the structure and causing a periodic surface displacement whose frequency is inversely proportional to the thickness of the test object. Impact-echo testing was chosen because it requires access to only one side of the test object and could be performed during the operation of a refractory structure. Commercially-available impact-echo instrumentation is available for room temperature use for a variety of tests on concrete. The enabling technology for this work was to use a high-temperature piezoelectric material, aluminum nitride, as the receiving sensor for the stress waves, allowing its use on refractories during furnace operation.

  1. Spatial Patterns of Climate Impact from Anthropogenic Aerosols in the Early Instrumental Period

    NASA Astrophysics Data System (ADS)

    Bollasina, M. A.; Undorf, S.; Hegerl, G. C.

    2015-12-01

    Anthropogenic aerosols have emerged as an important player affecting global and regional climate with significant impacts on both the energy and water cycles. The early instrumental period (1850-1950), characterized by the increase of North American and especially European aerosol emissions concurrently with negligible Asian emissions and relatively low carbon dioxide concentrations, is an interesting case study to isolate the aerosol impact.Observations and historical experiments with state-of-the-art CMIP5 models are used to identify regions affected by aerosols. We compare the spatial and temporal patterns of climate variables such as surface temperature and precipitation with those of aerosol emissions and aerosol optical depth (AOD). In addition to regions showing the expected relationship between increasing sulfate emissions and decreasing surface temperatures, we see regions and decades with a more complex temperature response, and the first third of the twentieth century stands out as an especially interesting period. The contribution of atmospheric circulation changes is also pointed out.

  2. Environmental impact assessment (EIA): an overlooked instrument for sustainable development in Pakistan.

    PubMed

    Saeed, Rashid; Sattar, Ayesha; Iqbal, Zafar; Imran, Muhammad; Nadeem, Raziya

    2012-04-01

    Environmental impact assessment (EIA) is a policy tool used for evaluating a project proposal from physical and socioeconomic environmental perspectives. Its aim is to reduce the impact of development on environment, hence, ensuring environmental sustainability. It is mandatory to submit an Environmental Impact Statement before starting a mega project as required by Environmental Protection Act of 1997 and Environmental Policy of Pakistan. Public consultation plays a key role in an EIA system, identifying the likely aspects and impacts of a development activity. This aspect has been ignored in effective enactment of environmental legislation in Pakistan. Sufficient legislative instruments are there to support EIA system in the country but the agencies responsible for the enforcement of environmental regulations have failed to do so. The current research gives an insight into the actual status of EIA system in Pakistan along with the feedback of EIA specialists and university teachers of the concerned departments. A new index has been devised on the basis of questionnaire response to work out the overall performance of EIA system in Pakistan or any other country. The weaknesses and deficiencies of each EIA stage have been worked out for Pakistan and elaborated with the help of the controversial Zero point Interchange Project in the capital city of Pakistan. PMID:21887481

  3. Outcome related to impact on daily living: preliminary validation of the ORIDL instrument

    PubMed Central

    Reilly, David; Mercer, Stewart W; Bikker, Annemieke P; Harrison, Tansy

    2007-01-01

    Background The challenge of finding practical, patient-rated outcome measures is a key issue in the evaluation of health care systems and interventions. The ORIDL (Outcome in Relation to Impact on Daily Living) instrument (formerly referred to as the Glasgow Homoeopathic Hospital Outcomes Scale or GHHOS) has been developed to measure patient's views of the outcome of their care by asking about change, and relating this to impact on daily life. The aim of the present paper is to describe the background and potential uses of the ORIDL, and to report on its preliminary validation in a series of three studies in secondary and primary care. Methods In the first study, 105 patients attending the Glasgow Homoeopathic Hospital (GHH) were followed-up at 12 months and changes in health status were measured by the EuroQol (EQOL) and the ORIDL. In the second study, 187 new patients at the GHH were followed-up at 3, 12, and 33 months, using the ORIDL, the Short Form 12 (SF-12), and the Measure Yourself Medical Outcome Profile (MYMOP). In study three, 323 patients in primary care were followed for 1 month post-consultation using the ORIDL and MYMOP. In all 3 studies the Patient Enablement Instrument (PEI) was also used as an outcome measure. Results Study 1 showed substantial improvements in main complaint and well-being over 12 months using the ORIDL, with two-thirds of patients reporting improvements in daily living. These improvements were not significantly correlated with changes in serial measures of the EQOL between baseline and 12 months, but were correlated with the EQOL transitions measure. Study 2 showed step-wise improvements in ORIDL scores between 3 and 33 months, which were only weakly associated with similar changes in SF-12 scores. However, MYMOP change scores correlated well with ORIDL scores at all time points. Study 3 showed similar high correlations between ORIDL scores and MYMOP scores. In all 3 studies, ORIDL scores were also significantly correlated with

  4. Charpy toughness and tensile properties of a neutron irradiated stainless steel submerged-arc weld cladding overlay

    SciTech Connect

    Corwin, W.R.; Berggren, R.G.; Nanstad, R.K.

    1984-01-01

    The possibility of stainless steel cladding increasing the resistance of an operating nuclear reactor pressure vessel to extension of surface flaws is highly dependent upon the irradiated properties of the cladding. Therefore, weld overlay cladding irradiated at temperatures and fluences relevant to power reactor operation was examined. The cladding was applied to a pressure vessel steel plate by the submerged-arc, single-wire, oscillating electrode method. Three layers of cladding were applied to provide a cladding thickness adequate for fabrication of test specimens. The first layer was type 309, and the upper two layers were type 308 stainless steel. There was considerable dilution of the type 309 in the first layer of cladding as a result of excessive melting of the base plate. Specimens for the irradiation study were taken from near the base plate/cladding interface and also from the upper layers of cladding. Charpy V-notch and tensile specimens were irradiated at 288/sup 0/C to neutron fluences of 2 x 10/sup 23/ n/m/sup 2/ (E > 1 MeV). When irradiated, both types 308 and 309 cladding showed a 5 to 40% increase in yield strength accompanied by a slight increase in ductility in the temperature range from 25 to 288/sup 0/C. All cladding exhibited ductile-to-brittle transition behavior during impact testing.

  5. Field observations of particle impacts by debris flows and debris floods on instrumented rock samples

    NASA Astrophysics Data System (ADS)

    McArdell, B. W.; Hsu, L.; Fritschi, B.; Dietrich, W. E.

    2011-12-01

    Bedrock incision and sediment entrainment by debris flows are important processes in torrent channels. As part of our effort to gain a better understanding of these processes, we installed instrumented rock samples in the bed of the Illgraben channel. Three rock samples, 0.4 m long (in the flow direction), 0.3 m wide, and 0.2 m thick, were installed in steel frames which were mounted on the upslope side of a concrete check dam, with the surface of the stones flush with the channel bed. Accelerometer sensors were installed on the bottom of one rock sample, with a range of up to 500 g (vertical) and 200 g (horizontal, parallel to the channel axis), where g is the acceleration due to gravity. Elastomer elements, typically used in the field as overload protection for load sensors, were placed between the rock samples and the steel frames. Data were sampled at 2 kHz and stored on a computer outside of the channel. The sensors provided data for 4 debris floods and part of one debris flow. For all of the events, the vertical acceleration data indicate a large background noise in the range of ±10 g, punctuated by very short duration impulses of up to several hundred g. The large accelerations are interpreted to represent hard impacts of cobbles or boulders in the flow with the rock tablet. Using a value of >20 g to define the occurrence of a large particle impact, it is possible to differentiate between debris floods (which have on the order of 0.1 impact per second) and the debris flow (on the order of 1 impact per second). The frequency of the sampling is too small to resolve details about the impacts, so it is not possible to precisely determine the maximum accelerations. However the peak recorded values are larger for debris flows, with values up to the measurement limit of the sensors, whereas for floods the maximum accelerations are typically less than 100 g. The results for the accelerometer which measures accelerations in the downstream direction generally mirror

  6. Impact of and correction for instrument sensitivity drift on nanoparticle size measurements by single-particle ICP-MS.

    PubMed

    El Hadri, Hind; Petersen, Elijah J; Winchester, Michael R

    2016-07-01

    The effect of ICP-MS instrument sensitivity drift on the accuracy of nanoparticle (NP) size measurements using single particle (sp)ICP-MS is investigated. Theoretical modeling and experimental measurements of the impact of instrument sensitivity drift are in agreement and indicate that drift can impact the measured size of spherical NPs by up to 25 %. Given this substantial bias in the measured size, a method was developed using an internal standard to correct for the impact of drift and was shown to accurately correct for a decrease in instrument sensitivity of up to 50 % for 30 and 60 nm gold nanoparticles. Graphical Abstract Correction of nanoparticle size measurement by spICP-MS using an internal standard. PMID:26894759

  7. Mass spectra of organic and inorganic dust particles measured by an impact ionization mass analyzer instrument

    NASA Astrophysics Data System (ADS)

    Salter, J. G.; Sternovsky, Z.; Srama, R.; Postberg, F.; Kempf, S.; Armes, S. P.; Gruen, E.; Horanyi, M.; Drake, K.; Westphal, A.

    2009-12-01

    The composition of individual cosmic dust particles can be measured in-situ using existing techniques and instrumentations. The dust particle impacting on a solid surface with hypervelocity (> 1 km/s) is vaporized and partially ionized. The generated ions are extracted and analyzed using time-of-flight methods. Laboratory calibration measurements are possible at the dust accelerator facility in Heidelberg, Germany. The accelerator is limited to using conductive dust that was limited in the past to Fe, Al or graphite samples. In the recent years, however, dust samples of organic materials and inorganic minerals of cosmic interest were developed that are suitable for application in the accelerator. This is achieved by coating micron and submicron sized dust particles by conductive polymers. Here we present the comparison of spectra measured using organic and inorganic dust samples (polystyrene, poly-[bis(4-vinylthiophenyl)sulphide], Phyrotite). The particles were accelerated to speeds between 3 and 35 km/s. Depending on the projectile type and the impact speed, both aliphatic and aromatic molecular ions and cluster species were identified in the mass spectra with masses up to 400 Daltons. Clusters resulting from the target material (silver) and mixed clusters of target and projectile species were also observed. These fundamental studies are expected to enhance our understanding of cometary, interplanetary and interstellar dust grains, which travel at similar hyper-velocities and are known to contain both aliphatic and aromatic organic compounds.

  8. Should different impact assessment instruments be integrated? Evidence from English spatial planning

    SciTech Connect

    Tajima, Ryo; Fischer, Thomas B.

    2013-07-15

    This paper aims at providing empirical evidence to the question as to whether integration of different instruments is achieving its aim in supporting sustainable decision making, focusing on SEA inclusive sustainability appraisal (SA) and other impact assessments (IAs) currently used in English spatial planning. Usage of IAs in addition to SA is established and an analysis of the integration approach (in terms of process, output, and assessor) as well as its effectiveness is conducted. It is found that while integration enhances effectiveness to some extent, too much integration, especially in terms of the procedural element, appears to diminish the overall effectiveness of each IA in influencing decisions as they become captured by the balancing function of SA. -- Highlights: ► The usage of different impact assessments in English spatial planning is clarified. ► The relationship between integration approach and effectiveness is analyzed. ► Results suggest that integration does not necessarily lead to more sustainable decisions. ► Careful consideration is recommended upon process integration.

  9. Spatial patterns of substantial climate impact from anthropogenic aerosols in the early instrumental period

    NASA Astrophysics Data System (ADS)

    Undorf, Sabine; Bollasina, Massimo; Hegerl, Gabriele

    2016-04-01

    While many aspects of climate variation in the early instrumental period (1860-1950) are still unexplained, for instance the early twentieth-century warming from the 1910s to the 1940s, the role of anthropogenic aerosols in this period has been overlooked. Yet, the period is also an interesting case study to isolate aerosol impacts since it is characterised by the increase of North American and especially European aerosol emissions concurrently with negligible Asian emissions and relatively low carbon dioxide concentrations. We thus analyse the spatial and temporal patterns of aerosol impact for this period in available observations (NOAA 20th-century reanalysis, etc.) and historical single-forcing and all-forcing experiments with state-of-the-art CMIP5 models. We make use of coupled empirical orthogonal functions (EOFs) applied to surface temperature -the most reliable variable in observations- and different aerosol indicating variables such as aerosol optical depth and short-wave downward radiation, some of which include aerosol indirect effects. The principal components of the most important EOFs are then regressed onto sea level pressure, winds, and other variables to identify associated circulation patterns. A decomposition into multi-decadal and longer time scales is performed by filtering the data prior to the analysis. Our analysis reveals both statistically significant local and non-local aerosol impact and identifies circulation states associated with the temperature response. The results are consistent across different aerosol variables, and show a strong non-local response as well as specific differences between time scales. We find a distinctive circulation pattern which strongly resembles observations and might explain the observed early twentieth century warming in the Arctic.

  10. Neighborhood Poverty Impacts Children's Physical Health and Well-Being over Time: Evidence from the Early Development Instrument

    ERIC Educational Resources Information Center

    Cushon, Jennifer A.; Vu, Lan T. H.; Janzen, Bonnie L.; Muhajarine, Nazeem

    2011-01-01

    Research Findings: The purpose of this study was to investigate how neighborhoods and neighborhood socioeconomic disadvantage impact school readiness over time. School readiness was measured using the Early Development Instrument (EDI) for 3 populations of kindergartners in 2001, 2003, and 2005 in Saskatoon, Saskatchewan, Canada. EDI results…

  11. Data-Informed Decision Making on High-Impact Strategies: Developing and Validating an Instrument for Principals

    ERIC Educational Resources Information Center

    Shen, Jianping; Cooley, Van E.; Ma, Xin; Reeves, Patricia L.; Burt, Walter L.; Rainey, J. Mark; Yuan, Wenhui

    2012-01-01

    In this study, the authors connect 3 streams of literature to develop an instrument for measuring the degree to which principals engage in data-informed decision making on high-impact strategies that are empirically associated with higher student achievement. The 3 literature streams are (a) the importance of data-informed decision making, (b) the…

  12. The impact of clinical use on the torsional behavior of Reciproc and WaveOne instruments

    PubMed Central

    de MAGALHÃES, Rafael Rodrigues Soares; BRAGA, Lígia Carolina Moreira; PEREIRA, Érika Sales Joviano; PEIXOTO, Isabella Faria da Cunha; BUONO, Vicente Tadeu Lopes; BAHIA, Maria Guiomar de Azevedo

    2016-01-01

    ABSTRACT Torsional overload is a fracture representative parameter for instruments in single-file techniques. Objective The aim of this study was to assess the influence of clinical use, in vivo, on the torsional behavior of Reciproc and WaveOne instruments considering the possibility that they degraded with use. Material and Methods Diameter at each millimeter, pitch length, and area at 3 mm from the tip were determined for both types of instruments. Twenty-four instruments, size 25, 0.08 taper, of each system were divided into two groups (n=12 each): Control Group (CG), in which new Reciproc (RC) and WaveOne Primary (WO) instruments were tested in torsion until rupture based on ISO 3630-1; and Experimental Group (EG), in which each new instrument was clinically used to clean and shape the root canals of one molar. After clinical use, the instruments were analyzed using optical and scanning electron microscopy and subsequently tested in torsion until fracture. Data were analyzed using one-way analysis of variance at a=.05. Results WO instruments showed significantly higher mean values of cross-sectional area A3 (P=0.000) and smaller pitch lengths than RC instruments with no statistically significant differences in the diameter at D3 (P=0.521). No significant differences in torsional resistance between the RC and WO new instruments (P=0.134) were found. The clinical use resulted in a tendency of reduction in the maximum torque of the analyzed instruments but no statistically significant difference was observed between them (P=0.327). During the preparation of the root canals, two fractured RC instruments and longitudinal and transversal cracks in RC and WO instruments were observed through SEM analysis. Conclusion After clinical use, no statistically significant reduction in the torsional resistance was observed. PMID:27556200

  13. Investigations of the Impacts of Instrumental and Operational Variables on Color Measurements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Color measurements for the classing of U.S. cottons have been performed on the Uster™ High Volume Instrumentation (HVI) instrument for several years. Two color parameters specific to cotton—Rd (reflectance) and +b (yellowness)—are used in the color measurement of cotton. Since Rd and +b do not rea...

  14. NASA 2014 The Hyperspectral Infrared Imager (HyspIRI) - Science Impact of Deploying Instruments on Separate Platforms

    NASA Technical Reports Server (NTRS)

    Turpie, Kevin; Veraverbeke, Sander; Wright, Robert; Anderson, Martha; Prakash, Anupma; Quattrochi, Dale

    2014-01-01

    The Hyperspectral Infrared Imager (HyspIRI) mission was recommended for implementation by the 2007 report from the U.S. National Research Council Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond, also known as the Earth Science Decadal Survey. The HyspIRI mission is science driven and will address a set of science questions identified by the Decadal Survey and broader science community. The mission includes a visible shortwave infrared (VSWIR) imaging spectrometer, a multispectral thermal infrared (TIR) imager and an intelligent payload module (IPM). The IPM enables on-board processing and direct broadcast for those applications with short latency requirements. The science questions are organized as VSWIR-only, TIR-only and Combined science questions, the latter requiring data from both instruments. In order to prepare for the mission NASA is undertaking pre-phase A studies to determine the optimum mission implementation, in particular, cost and risk reduction activities. Each year the HyspIRI project is provided with feedback from NASA Headquarters on the pre-phase A activities in the form of a guidance letter which outlines the work that should be undertaken the subsequent year. The 2013 guidance letter included a recommendation to undertake a study to determine the science impact of deploying the instruments from separate spacecraft in sun synchronous orbits with various time separations and deploying both instruments on the International Space Station (ISS). This report summarizes the results from that study. The approach taken was to evaluate the impact on the combined science questions of time separations between the VSWIR and TIR data of <3 minutes, <1 week and a few months as well as deploying both instruments on the ISS. Note the impact was only evaluated for the combined science questions which require data from both instruments (VSWIR and TIR). The study concluded the impact of a separation of <3 minutes was

  15. Impact of Instrumented Spinal Fusion on the Development of Vertebral Compression Fracture.

    PubMed

    Chiu, Yen-Chun; Tsai, Tsung-Ting; Yang, Shih-Chieh; Chen, Hung-Shu; Kao, Yu-Hsien; Tu, Yuan-Kun

    2016-04-01

    Instrumented spinal fusion has become one of the most common surgeries for patients with various spinal disorders. Only few studies have reported subsequent vertebral compression fractures (VCFs) after instrumented spinal fusion. The purpose of this study was to evaluate the risk of new VCFs in patients undergoing instrumented spinal fusion.We obtained claims data from the National Health Insurance Research Database of Taiwan and retrospectively reviewed 6949 patients with instrumented spinal fusion as the spinal fusion cohort. Control subjects were individually matched at a ratio of 10:1 with those of the spinal fusion cohort according to age, sex, and the index day. Comorbidities were classified as those existing before the index day, and these included diabetes mellitus, hypertension, osteoporosis, and cerebrovascular accident. The end of the follow-up period for the analyses was marked on the day new VCFs developed, enrolment in the National Health Insurance was terminated, on the day of death, or until the end of 2012. We used the Cox proportion hazards model to analyze the hazard ratio (HR) for developing new VCFs.Patients with instrumented spinal fusion were significantly more likely to develop new VCFs (1.87% vs .25%, HR: 8.56; P < 0.001). Female, elderly, and osteoporotic patients had a high incidence of new VCFs after spinal fusion. The HR for developing new VCFs after instrumented spinal fusion was higher in patients younger than 65 years than in those 65 years or older (HR: 10.61 vs 8.09). Male patients with instrumented spinal fusion also had a higher HR of developing new VCFs than female patients (men, HR: 26.42; women, HR: 7.53).In our retrospective cohort study, patients who had undergone instrumented spinal fusion surgery exhibited an increased risk of developing new VCFs. Particularly, the HR increased in young (age <65 years) and male patients. PMID:27124040

  16. Impact of Instrumented Spinal Fusion on the Development of Vertebral Compression Fracture

    PubMed Central

    Chiu, Yen-Chun; Tsai, Tsung-Ting; Yang, Shih-Chieh; Chen, Hung-Shu; Kao, Yu-Hsien; Tu, Yuan-Kun

    2016-01-01

    Abstract Instrumented spinal fusion has become one of the most common surgeries for patients with various spinal disorders. Only few studies have reported subsequent vertebral compression fractures (VCFs) after instrumented spinal fusion. The purpose of this study was to evaluate the risk of new VCFs in patients undergoing instrumented spinal fusion. We obtained claims data from the National Health Insurance Research Database of Taiwan and retrospectively reviewed 6949 patients with instrumented spinal fusion as the spinal fusion cohort. Control subjects were individually matched at a ratio of 10:1 with those of the spinal fusion cohort according to age, sex, and the index day. Comorbidities were classified as those existing before the index day, and these included diabetes mellitus, hypertension, osteoporosis, and cerebrovascular accident. The end of the follow-up period for the analyses was marked on the day new VCFs developed, enrolment in the National Health Insurance was terminated, on the day of death, or until the end of 2012. We used the Cox proportion hazards model to analyze the hazard ratio (HR) for developing new VCFs. Patients with instrumented spinal fusion were significantly more likely to develop new VCFs (1.87% vs .25%, HR: 8.56; P < 0.001). Female, elderly, and osteoporotic patients had a high incidence of new VCFs after spinal fusion. The HR for developing new VCFs after instrumented spinal fusion was higher in patients younger than 65 years than in those 65 years or older (HR: 10.61 vs 8.09). Male patients with instrumented spinal fusion also had a higher HR of developing new VCFs than female patients (men, HR: 26.42; women, HR: 7.53). In our retrospective cohort study, patients who had undergone instrumented spinal fusion surgery exhibited an increased risk of developing new VCFs. Particularly, the HR increased in young (age <65 years) and male patients. PMID:27124040

  17. Fiber-matrix integrity, micromorphology and flexural strength of glass fiber posts: Evaluation of the impact of rotary instruments.

    PubMed

    Pereira, Gabriel Kalil Rocha; Lançanova, Mateus; Wandscher, Vinicius Felipe; Kaizer, Osvaldo Bazzan; Limberger, Inácio; Özcan, Mutlu; Valandro, Luiz Felipe

    2015-08-01

    Several rotary instruments have been daily employed on clinic to promote cut aiming to adjust the length of fiber posts to the radicular conduct, but there is no information on the literature about the effects of the different rotary instruments and its impact on the micromorphology of surface and mechanical properties of the glass fiber post. This study aimed the impact of rotary instruments upon fiber-matrix integrity, micromorphology and flexural-strength of glass-fiber posts (GFP). GFP (N=110) were divided into 5 groups: Ctrl: as-received posts, DBc: coarse diamond-bur, DBff: extra-fine diamond-bur, CB: carbide-bur, DD: diamond-disc. Cutting procedures were performed under abundant irrigation. Posts exposed to rotary instruments were then subjected to 2-point inclined loading test (compression 45°) (n=10/group) and 3-point flexural-strength test (n=10/group). Fiber-matrix integrity and micromorphology at the cut surface were analyzed using a SEM (n=2/group). Cutting procedures did not significantly affect the 2-point (51.7±4.3-56.7±5.1 MPa) (p=0.0233) and 3-point flexural-strength (671.5±35.3-709.1±33.1 MPa) (p=0.0968) of the posts (One-way ANOVA and Tukey׳s test). Fiber detachment was observed only at the end point of the cut at the margins of the post. Cut surfaces of the CB group were smoother than those of the other groups. After 3-point flexural strength test, fiber-matrix separation was evident at the tensile side of the post. Rotary instruments tested with simultaneous water-cooling did not affect the resistance of the tested fiber posts but caused disintegration of the fibers from the matrix at the end of the cut, located at the margins. PMID:25955561

  18. Motivations Impacting upon Music Instrument Teachers' Decisions to Teach and Perform in Higher Education

    ERIC Educational Resources Information Center

    Parkes, Kelly A.; Daniel, Ryan

    2013-01-01

    The purpose of this study was to explore why highly trained musicians choose to teach in higher education. An international population from nine countries of music instrument teachers was sampled via online survey, to determine their reasons for teaching in higher education. Motivational constructs from the expectancy-value framework were used,…

  19. Student Evaluation Instruments: The Interactive Impact of Course Requirement, Student Level, Department and Anticipated Grade

    ERIC Educational Resources Information Center

    Driscoll, Jennifer; Cadden, David

    2010-01-01

    The examination of Student Evaluation Instruments (SEI) has generated a considerable literature. Interestingly, this extensive literature provides no clear guidance on how to interpret SEI results in order to make comparative evaluations of instructors' performances. The research presented in this paper draws upon six semesters worth of SEI…

  20. Instrumented Taylor anvil-on-rod impact tests for validating applicability of standard strength models to transient deformation states

    NASA Astrophysics Data System (ADS)

    Eakins, D. E.; Thadhani, N. N.

    2006-10-01

    Instrumented Taylor anvil-on-rod impact tests have been conducted on oxygen-free electronic copper to validate the accuracy of current strength models for predicting transient states during dynamic deformation events. The experiments coupled the use of high-speed digital photography to record the transient deformation states and laser interferometry to monitor the sample back (free surface) velocity as a measure of the elastic/plastic wave propagation through the sample length. Numerical continuum dynamics simulations of the impact and plastic wave propagation employing the Johnson-Cook [Proceedings of the Seventh International Symposium on Ballistics, 1983, The Netherlands (Am. Def. Prep. Assoc. (ADPA)), pp. 541-547], Zerilli-Armstrong [J. Appl. Phys. C1, 1816 (1987)], and Steinberg-Guinan [J. Appl. Phys. 51, 1498 (1980)] constitutive equations were used to generate transient deformation profiles and the free surface velocity traces. While these simulations showed good correlation with the measured free surface velocity traces and the final deformed sample shape, varying degrees of deviations were observed between the photographed and calculated specimen profiles at intermediate deformation states. The results illustrate the usefulness of the instrumented Taylor anvil-on-rod impact technique for validating constitutive equations that can describe the path-dependent deformation response and can therefore predict the transient and final deformation states.

  1. The Impact of Scholastic Instrumental Music and Scholastic Chess Study on the Standardized Test Scores of Students in Grades Three, Four, and Five

    ERIC Educational Resources Information Center

    Martinez, Edwin E.

    2012-01-01

    This study examines the impact of instrumental music study and group chess lessons on the standardized test scores of suburban elementary public school students (grades three through five) in Levittown, New York. The study divides the students into the following groups and compares the standardized test scores of each: a) instrumental music…

  2. INSTRUMENTS AND METHODS OF INVESTIGATION: Deep Impact experiment: possible observable effects

    NASA Astrophysics Data System (ADS)

    Klumov, Boris A.; Kim, V. V.; Lomonosov, I. V.; Sultanov, Valerii G.; Shutov, A. V.; Fortov, Vladimir E.

    2005-07-01

    A hypervelocity collision of a metal impactor and the nucleus of the Tempel 1 comet is to be carried out in July 2005 in the framework of the Deep Impact active experiment in space. This paper discusses certain observable consequences of this impact. Numerical simulation of the impact process made it possible to evaluate the diameter of the impact-produced crater as a function of the initial density and porosity of the cometary nucleus. A substantial part of the shockwave-compressed cometary material that is evaporated at the unloading stage may become heated to temperatures on the order of (1-2)×104 K. A change in the chemical composition of the hot vapor in the process of its expansion was computed using a model elemental composition of the cometary nucleus; this may prove useful for determining the parameters of the flash induced by the impact in the visible optical, UV, IR, and radio wavelength bands.

  3. The Impact of Instrument-Specific Musical Training on Rhythm Perception and Production

    PubMed Central

    Matthews, Tomas E.; Thibodeau, Joseph N. L.; Gunther, Brian P.; Penhune, Virginia B.

    2016-01-01

    Studies comparing musicians and non-musicians have shown that musical training can improve rhythmic perception and production. These findings tell us that training can result in rhythm processing advantages, but they do not tell us whether practicing a particular instrument could lead to specific effects on rhythm perception or production. The current study used a battery of four rhythm perception and production tasks that were designed to test both higher- and lower-level aspects of rhythm processing. Four groups of musicians (drummers, singers, pianists, string players) and a control group of non-musicians were tested. Within-task differences in performance showed that factors such as meter, metrical complexity, tempo, and beat phase significantly affected the ability to perceive and synchronize taps to a rhythm or beat. Musicians showed better performance on all rhythm tasks compared to non-musicians. Interestingly, our results revealed no significant differences between musician groups for the vast majority of task measures. This was despite the fact that all musicians were selected to have the majority of their training on the target instrument, had on average more than 10 years of experience on their instrument, and were currently practicing. These results suggest that general musical experience is more important than specialized musical experience with regards to perception and production of rhythms. PMID:26869969

  4. A head impact detection system using SVM classification and proximity sensing in an instrumented mouthguard.

    PubMed

    Wu, Lyndia C; Zarnescu, Livia; Nangia, Vaibhav; Cam, Bruce; Camarillo, David B

    2014-11-01

    Injury from blunt head impacts causes acute neurological deficits and may lead to chronic neurodegeneration. A head impact detection device can serve both as a research tool for studying head injury mechanisms and a clinical tool for real-time trauma screening. The simplest approach is an acceleration thresholding algorithm, which may falsely detect high-acceleration spurious events such as manual manipulation of the device. We designed a head impact detection system that distinguishes head impacts from nonimpacts through two subsystems. First, we use infrared proximity sensing to determine if the mouthguard is worn on the teeth to filter out all off-teeth events. Second, on-teeth, nonimpact events are rejected using a support vector machine classifier trained on frequency domain features of linear acceleration and rotational velocity. The remaining events are classified as head impacts. In a controlled laboratory evaluation, the present system performed substantially better than a 10-g acceleration threshold in head impact detection (98% sensitivity, 99.99% specificity, 99% accuracy, and 99.98% precision, compared to 92% sensitivity, 58% specificity, 65% accuracy, and 37% precision). Once adapted for field deployment by training and validation with field data, this system has the potential to effectively detect head trauma in sports, military service, and other high-risk activities. PMID:24800918

  5. Impact of Distortions on Fiber Position Location in the dark Energy Spectroscopic Instrument

    SciTech Connect

    Kent, Stephen; Lampton, Michael; Doel, A. Peter; Brooks, David; Miller, Tim; Besuner, Robert; Silber, Joe; Liang, Ming; Sprayberry, David; Baltay, Charles; Rabinowitz, David

    2016-01-01

    The Dark Energy Spectroscopic Instrument, to be located at the prime focus of the Mayall telescope, includes a wide field corrector, a 5000 fiber positioner system, and a fiber view camera. The mapping of the sky to the focal plane, needed to position the fibers accurately, is described in detail. A major challenge is dealing with the large amount of distortion introduced by the optics (of order 10% scale change), including time-dependent non-axisymmetric distortions introduced by the atmospheric dispersion compensator. Solutions are presented to measure or mitigate these effects.

  6. Impact of Passive Safety on FHR Instrumentation Systems Design and Classification

    SciTech Connect

    Holcomb, David Eugene

    2015-01-01

    Fluoride salt-cooled high-temperature reactors (FHRs) will rely more extensively on passive safety than earlier reactor classes. 10CFR50 Appendix A, General Design Criteria for Nuclear Power Plants, establishes minimum design requirements to provide reasonable assurance of adequate safety. 10CFR50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors, provides guidance on how the safety significance of systems, structures, and components (SSCs) should be reflected in their regulatory treatment. The Nuclear Energy Institute (NEI) has provided 10 CFR 50.69 SSC Categorization Guideline (NEI-00-04) that factors in probabilistic risk assessment (PRA) model insights, as well as deterministic insights, through an integrated decision-making panel. Employing the PRA to inform deterministic requirements enables an appropriately balanced, technically sound categorization to be established. No FHR currently has an adequate PRA or set of design basis accidents to enable establishing the safety classification of its SSCs. While all SSCs used to comply with the general design criteria (GDCs) will be safety related, the intent is to limit the instrumentation risk significance through effective design and reliance on inherent passive safety characteristics. For example, FHRs have no safety-significant temperature threshold phenomena, thus enabling the primary and reserve reactivity control systems required by GDC 26 to be passively, thermally triggered at temperatures well below those for which core or primary coolant boundary damage would occur. Moreover, the passive thermal triggering of the primary and reserve shutdown systems may relegate the control rod drive motors to the control system, substantially decreasing the amount of safety-significant wiring needed. Similarly, FHR decay heat removal systems are intended to be running continuously to minimize the amount of safety-significant instrumentation needed to initiate

  7. In Their Voice: Lower Secondary School Students' Beliefs about Playing Musical Instruments, and the Impact of the Instrument Lesson upon Those Beliefs

    ERIC Educational Resources Information Center

    Lowe, Geoffrey

    2010-01-01

    Many young West Australians learn musical instruments through school based elective programs. However, many students drop out from these programs, particularly in lower secondary school. This paper reports on a study I conducted into the motives of 48 lower secondary school students for playing a musical instrument, and the role of the instrument…

  8. INSTRUMENTATION, RECORDING, AND PROCESSING OF METEOROLOGICAL DATA NEAR PORTAGE, WISCONSIN: WISCONSIN POWER PLANT IMPACT STUDY

    EPA Science Inventory

    As part of the Columbia Power Plant Impact Study meteorological data were collected at a network of monitoring sites from 1972 through 1977. The data were the basis for a series of studies whose purpose was to elucidate the transport of airborne pollutants and to assess the clima...

  9. New Instruments for Studying the Impacts of Science Teacher Professional Development

    ERIC Educational Resources Information Center

    Trygstad, Peggy J.; Banilower, Eric R.; Smith, P. Sean; Nelson, Courtney L.

    2014-01-01

    The logic model that implicitly drives most professional development (PD) efforts asserts that PD leads to changes in teacher knowledge and beliefs, which leads to improved classroom practice, and ultimately, better student outcomes. However, efforts to study the impacts of PD programs are often hampered by the scarcity of high-quality…

  10. Results and Insights on the Impact of Smoke on Digital Instrumentation and Control

    SciTech Connect

    Tanaka, T. J.; Nowlen, S. P.

    2001-01-31

    Smoke can cause interruptions and upsets in active electronics. Because nuclear power plants are replacing analog with digital instrumentation and control systems, qualification guidelines for new systems are being reviewed for severe environments such as smoke and electromagnetic interference. Active digital systems, individual components, and active circuits have been exposed to smoke in a program sponsored by the U.S. Nuclear Regulatory Commission. The circuits and systems were all monitored during the smoke exposure, indicating any immediate effects of the smoke. The major effect of smoke has been to increase leakage currents (through circuit bridging across contacts and leads) and to cause momentary upsets and failures in digital systems. This report summarizes two previous reports and presents new results from conformal coating, memory chip, and hard drive tests. The report describes practices for mitigation of smoke damage through digital system design, fire barriers, ventilation, fire suppressants, and post fire procedures.

  11. The impact patient-specific instrumentation has had on my practice in the last 5 years.

    PubMed

    Collins, Michael J

    2014-03-01

    I have performed total knee arthroplasty (TKA) using patient- specific instrumentation (PSI) (TRUMATCH® Personalized Solutions, DePuy Synthes Joint Reconstruction, Warsaw, Indiana) since July 2009. Since that time, I have performed over 600 of these procedures, all at the same hospital and all using the same personnel I worked with before I began using PSI. I do not have a physician assistant, but I do have a surgical assistant who scrubs with and assists me on all TKAs. There are a number of reasons why a surgeon may decide to use PSI. This paper discusses the effect PSI has had on my practice in the last 5 years, including my experiences and conclusions. PMID:24911641

  12. The Impact II, a Very High-Resolution Quadrupole Time-of-Flight Instrument (QTOF) for Deep Shotgun Proteomics*

    PubMed Central

    Beck, Scarlet; Michalski, Annette; Raether, Oliver; Lubeck, Markus; Kaspar, Stephanie; Goedecke, Niels; Baessmann, Carsten; Hornburg, Daniel; Meier, Florian; Paron, Igor; Kulak, Nils A.; Cox, Juergen; Mann, Matthias

    2015-01-01

    Hybrid quadrupole time-of-flight (QTOF) mass spectrometry is one of the two major principles used in proteomics. Although based on simple fundamentals, it has over the last decades greatly evolved in terms of achievable resolution, mass accuracy, and dynamic range. The Bruker impact platform of QTOF instruments takes advantage of these developments and here we develop and evaluate the impact II for shotgun proteomics applications. Adaption of our heated liquid chromatography system achieved very narrow peptide elution peaks. The impact II is equipped with a new collision cell with both axial and radial ion ejection, more than doubling ion extraction at high tandem MS frequencies. The new reflectron and detector improve resolving power compared with the previous model up to 80%, i.e. to 40,000 at m/z 1222. We analyzed the ion current from the inlet capillary and found very high transmission (>80%) up to the collision cell. Simulation and measurement indicated 60% transfer into the flight tube. We adapted MaxQuant for QTOF data, improving absolute average mass deviations to better than 1.45 ppm. More than 4800 proteins can be identified in a single run of HeLa digest in a 90 min gradient. The workflow achieved high technical reproducibility (R2 > 0.99) and accurate fold change determination in spike-in experiments in complex mixtures. Using label-free quantification we rapidly quantified haploid against diploid yeast and characterized overall proteome differences in mouse cell lines originating from different tissues. Finally, after high pH reversed-phase fractionation we identified 9515 proteins in a triplicate measurement of HeLa peptide mixture and 11,257 proteins in single measurements of cerebellum—the highest proteome coverage reported with a QTOF instrument so far. PMID:25991688

  13. Transverse and z-Direction CVN Impact Tests of X65 Line Pipe Steels of Two Centerline Segregation Ratings

    NASA Astrophysics Data System (ADS)

    Su, Lihong; Li, Huijun; Lu, Cheng; Li, Jintao; Fletcher, Leigh; Simpson, Ian; Barbaro, Frank; Zheng, Lei; Bai, Mingzhuo; Shen, Jianlan; Qu, Xianyong

    2016-06-01

    Centerline segregation occurs as a positive concentration of alloying elements in the mid-thickness region of continuously cast slab. Depending upon its severity, it may affect mechanical properties and potentially downstream processing such as weldability, particularly for high-strength line pipe. The segregation fraction in continuously cast slabs and corresponding hot-rolled strips was assessed on API 5L grade X65 line pipe steels with different levels of segregation, rated as Mannesmann 2.0 and 1.4. The results showed that the segregation fraction in hot-rolled strip samples was in accordance with that assessed in the cast slabs, and the segregated regions in hot-rolled strip samples were found to be discontinuous. Transverse and z-direction CVN impact tests were conducted on the two strips and the results showed that centerline segregation does have an influence on the Charpy impact properties of line pipe steel. Specimens located at segregated regions exhibited lower Charpy impact toughness and strips rolled from slabs with higher segregation levels are more likely to exhibit greater variability in Charpy impact toughness. The influence of centerline segregation on z-direction Charpy impact toughness is more severe than on transverse Charpy impact toughness. Lower Charpy impact toughness and brittle fracture surface with cleavage facets along with rod-shaped MnS inclusions were observed for the strip rolled from slab with 2.0 segregation rating if the Charpy specimens were located at segregated regions. The influence on Charpy impact toughness can be associated with the pearlite structure at the centerline and level of MnS inclusions.

  14. Transverse and z-Direction CVN Impact Tests of X65 Line Pipe Steels of Two Centerline Segregation Ratings

    NASA Astrophysics Data System (ADS)

    Su, Lihong; Li, Huijun; Lu, Cheng; Li, Jintao; Fletcher, Leigh; Simpson, Ian; Barbaro, Frank; Zheng, Lei; Bai, Mingzhuo; Shen, Jianlan; Qu, Xianyong

    2016-08-01

    Centerline segregation occurs as a positive concentration of alloying elements in the mid-thickness region of continuously cast slab. Depending upon its severity, it may affect mechanical properties and potentially downstream processing such as weldability, particularly for high-strength line pipe. The segregation fraction in continuously cast slabs and corresponding hot-rolled strips was assessed on API 5L grade X65 line pipe steels with different levels of segregation, rated as Mannesmann 2.0 and 1.4. The results showed that the segregation fraction in hot-rolled strip samples was in accordance with that assessed in the cast slabs, and the segregated regions in hot-rolled strip samples were found to be discontinuous. Transverse and z-direction CVN impact tests were conducted on the two strips and the results showed that centerline segregation does have an influence on the Charpy impact properties of line pipe steel. Specimens located at segregated regions exhibited lower Charpy impact toughness and strips rolled from slabs with higher segregation levels are more likely to exhibit greater variability in Charpy impact toughness. The influence of centerline segregation on z-direction Charpy impact toughness is more severe than on transverse Charpy impact toughness. Lower Charpy impact toughness and brittle fracture surface with cleavage facets along with rod-shaped MnS inclusions were observed for the strip rolled from slab with 2.0 segregation rating if the Charpy specimens were located at segregated regions. The influence on Charpy impact toughness can be associated with the pearlite structure at the centerline and level of MnS inclusions.

  15. Physicians' decision process for drug prescription and the impact of pharmaceutical marketing mix instruments.

    PubMed

    Campo, Katia; De Staebel, Odette; Gijsbrechts, Els; van Waterschoot, Walter

    2005-01-01

    This paper provides an in-depth, qualitative analysis of the physicians' decision process for drug prescription. Drugs in the considered therapeutic classes are mainly prescribed by specialists, treating patients with obligatory medical insurance, for a prolonged period of time. The research approach is specifically designed to capture the full complexity and sensitive nature of the physician's choice behavior, which appears to be more hybrid and less rational in nature than is often assumed in quantitative, model-based analyses of prescription behavior. Several interesting findings emerge from the analysis: (i) non-compensatory decision rules seem to dominate the decision process, (ii) consideration sets are typically small and change-resistant, (iii) drug cost is not a major issue for most physicians, (iv) detailing remains one of the most powerful pharmaceutical marketing instruments and is highly appreciated as a valuable and quick source of information, and (v) certain types of non-medical marketing incentives (such as free conference participation) may in some situations also influence drug choices. PMID:16597584

  16. Urban traffic-related determinants of health questionnaire (UTDHQ): an instrument developed for health impact assessments

    PubMed Central

    Nadrian, Haidar; Nedjat, Saharnaz; Taghdisi, Mohammad Hossein; Shojaeizadeh, Davoud

    2014-01-01

    Background: Traffic and transport is a substantial part of a range of economic, social and environmental factors distinguished to have impact on human health. This paper is a report on a preliminary section of a Health Impact Assessment (HIA) on urban traffic and transport initiatives, being conducted in Sanandaj, Iran. In this preliminary study, the psychometric properties of Urban Traffic related Determinants of Health Questionnaire (UTDHQ) were investigated. Methods: Multistage cluster sampling was employed to recruit 476 key informants in Sanandaj from April to June 2013 to participate in the study. The development of UTDHQ began with a comprehensive review of the literature. Then face, content and construct validity as well as reliability were determined. Results: Exploratory Factor Analysis showed optimal reduced solution including 40 items and 8 factors. Three of the factors identified were Physical Environment, Social Environment, Public Services Delivery and Accessibility. UTDHQ demonstrated an appropriate validity, reliability, functionality and simplicity. Conclusion: Despite the need for further studies on UTDHQ, this study showed that it can be a practical and useful tool for conducting HIAs in order to inform decision makers and stakeholders about the health influences of their decisions and measures. PMID:25664285

  17. [The impact of dental trauma on quality of life of children and adolescents: a critical review and measurement instruments].

    PubMed

    Antunes, Lívia Azeredo Alves; Leão, Anna Thereza; Maia, Lucianne Cople

    2012-12-01

    Dental trauma constitutes a public health problem with a marked prevalence among Brazilian children and adolescents. Furthermore, it can lead to irreparable dental loss, which makes it important to evaluate this condition using instruments of oral health related to quality of life (OHRQoL). Based on this, a review of the literature sought to expose indices that may assess the evaluation of quality of life among Brazilians with dental trauma, as well as discuss the state of the art of publications about this condition on their OHRQoL followed by a discussion of the output encountered on the subject. With this in mind the articles published from 1980 to June/2011 located on databases (Pubmed, VHL, Google Scholar) or manually in the references of selected publications were prioritized. It was revealed that there is no specific instrument for dental trauma. It is therefore necessary to assess the OHRQoL in children and adolescents with indices found in the literature. Once this has been done, as yet unresolved questions about the impact of dental trauma on OHRQoL can be answered. PMID:23175417

  18. Restoration of Images of Comet 9P/Tempel 1 Taken with the Deep Impact High Resolution Instrument

    NASA Astrophysics Data System (ADS)

    Lindler, D.; Busko, I.; A'Hearn, M. F.; White, R. L.

    2007-04-01

    In 2005 July, the NASA Deep Impact mission successfully completed a flyby of comet 9P/Tempel 1. A flaw in the prelaunch calibration system resulted in an inability to accurately focus the telescope's High Resolution Instrument, resulting in a significant loss of resolution. However, because of the nature of the blurring process, much of the high-frequency information is retained and can be recovered using deconvolution. We discuss the data-processing requirements and noise modeling needed prior to deconvolution and compare a few popular deconvolution algorithms. All of the algorithms give very similar results. More importantly, we find that none of the algorithms correctly handle the errors resulting from the data compression used on board the spacecraft to compress the 16 bit CCD data to 8 bits prior to transmission of the image to the ground. We present a modification to the Richardson-Lucy deconvolution algorithm that we have successfully used to account for these compression errors.

  19. Impact of mixing height estimation on heterogeneous terrains with different algorithms and instruments on atmospheric transport models.

    NASA Astrophysics Data System (ADS)

    Biavati, G.; Kretschmer, R.; Gerbig, C.; Feist, D. G.

    2012-04-01

    The retrieval of mixing height [MH] is a common target of several scientific community all over the world. A strong effort is needed to the fact that modeling of MH generally fails introducing strong errors in the estimate of the concentrations of pollutants and green house gasses within the boundary layer. In Europe local meteorological services and international projects are implementing networks of instruments that can provide atmospheric profiles of different quantities. These networks will continuously provide data which could be used to constrain MH values. The current availability of atmospheric profiles of different nature, such as radiosondes, ground based lidar and ceilometers as well as satellites over Europe grant a spatial coverage that allow to estimate the impact of the knowledge of MH on transport models at synoptic scale of quantities as CO2 and CH4 mixing ratios. In this study we apply several algorithms to retrieve MH from different data sources: the ceilometers network installed by the German Weather Service; the data from CALIPSO satellite and all the WMO radio-soundings available over Europe during the IMECC (Infrastructure for Measurements of the European Carbon Cycle) in 2009. The values obtained from the optical instruments are validated using as reference the estimation retrieved by the virtual potential temperature profiles obtained by the radiosondes where co-location occurs and using statistical interpolation to evaluate the estimates from satellite and non co-located stations.. The impact of this estimates of MH on CO2 mixing ratios will be evaluated with the Stochastic Time Inverted Lagrangian Transport model (STILT) driven by WRF meteorology in comparison with in-situ measurements.

  20. Impact Tests for Woods

    NASA Technical Reports Server (NTRS)

    1922-01-01

    Although it is well known that the strength of wood depends greatly upon the time the wood is under the load, little consideration has been given to this fact in testing materials for airplanes. Here, results are given of impact tests on clear, straight grained spruce. Transverse tests were conducted for comparison. Both Izod and Charpy impact tests were conducted. Results are given primarily in tabular and graphical form.

  1. Test and Calibration of The Impact Sensor Experiment For The Giada Instrument Aboard The Rosetta Mission

    NASA Astrophysics Data System (ADS)

    Esposito, F.; della Corte, V.; Palumbo, P.; Colangeli, L.; International Giada Team

    The Impact Sensor is a device for the measurement of the momentum of grains ejected from a cometary nucleus and impinging over its sensitive surface. It is a square di- aphragm (124 x 124 x 0.5) mm^3 equipped with five piezoelectric sensors placed beneath the centre and each corner of the diaphragm. Momenta of impinging particles turn out to be proportional to the maximum amplitude of the principal flexural wave which propagates along the diaphragm after a collision event. When this perturbation reaches the sensors, they respond with a proportional voltage. So, after the calibra- tion procedure, the sensors response can be linked to the particles momentum. The IS flight model has been completely calibrated and released to ESA. The dinamical range of detectable momenta is 7.5 E-11 - 5 E-4 Ns. Here we present the results of the calibration tests.

  2. Using instrumental neutron activation analysis for geochemical analyses of terrestrial impact structures: current analytical procedures at the university of vienna geochemistry activation analysis laboratory.

    PubMed

    Mader, Dieter; Koeberl, Christian

    2009-12-01

    The Instrumental Neutron Activation Analysis Gamma Spectroscopy Laboratory at the Department of Lithospheric Research, University of Vienna, has been upgraded in the year 2006. This paper describes the sample preparation, new instrumentation and data evaluation for hundreds of rock samples of two terrestrial impact structures. The measurement and data evaluation are done by using Genie 2000 and a custom-made batch software for the used analysis sequences. PMID:19481467

  3. Understanding human visual systems and its impact on our intelligent instruments

    NASA Astrophysics Data System (ADS)

    Strojnik Scholl, Marija; Páez, Gonzalo; Scholl, Michelle K.

    2013-09-01

    We review the evolution of machine vision and comment on the cross-fertilization from the neural sciences onto flourishing fields of neural processing, parallel processing, and associative memory in optical sciences and computing. Then we examine how the intensive efforts in mapping the human brain have been influenced by concepts in computer sciences, control theory, and electronic circuits. We discuss two neural paths that employ the input from the vision sense to determine the navigational options and object recognition. They are ventral temporal pathway for object recognition (what?) and dorsal parietal pathway for navigation (where?), respectively. We describe the reflexive and conscious decision centers in cerebral cortex involved with visual attention and gaze control. Interestingly, these require return path though the midbrain for ocular muscle control. We find that the cognitive psychologists currently study human brain employing low-spatial-resolution fMRI with temporal response on the order of a second. In recent years, the life scientists have concentrated on insect brains to study neural processes. We discuss how reflexive and conscious gaze-control decisions are made in the frontal eye field and inferior parietal lobe, constituting the fronto-parietal attention network. We note that ethical and experiential learnings impact our conscious decisions.

  4. Effect of angleplying and matrix enhancement on impact-resistant boron/aluminum composites

    NASA Technical Reports Server (NTRS)

    Mcdanels, D. L.; Signorelli, R. A.

    1976-01-01

    Efforts to improve the impact resistance of B/Al are reviewed and analyzed. Tensile and dynamic modulus tests, thin sheet Charpy and Izod impact tests, and standard full size Charpy impact tests were conducted on 0.20 mm (8 mil) diameter-B/1100 Al matrix composites. Angleplies ranged from unidirectional to + or - 30 deg. The best compromise between reduced longitudinal properties and increased transverse properties was obtained with + or - 15 deg angleply. The pendulum impact strengths of improved B/Al were higher than that of notched titanium and appear to be enough to warrant consideration of B/Cl for application to fan blades in aircraft gas turbine engines.

  5. Development of a Simple 12-Item Theory-Based Instrument to Assess the Impact of Continuing Professional Development on Clinical Behavioral Intentions

    PubMed Central

    Légaré, France; Borduas, Francine; Freitas, Adriana; Jacques, André; Godin, Gaston; Luconi, Francesca; Grimshaw, Jeremy

    2014-01-01

    Background Decision-makers in organizations providing continuing professional development (CPD) have identified the need for routine assessment of its impact on practice. We sought to develop a theory-based instrument for evaluating the impact of CPD activities on health professionals' clinical behavioral intentions. Methods and Findings Our multipronged study had four phases. 1) We systematically reviewed the literature for instruments that used socio-cognitive theories to assess healthcare professionals' clinically-oriented behavioral intentions and/or behaviors; we extracted items relating to the theoretical constructs of an integrated model of healthcare professionals' behaviors and removed duplicates. 2) A committee of researchers and CPD decision-makers selected a pool of items relevant to CPD. 3) An international group of experts (n = 70) reached consensus on the most relevant items using electronic Delphi surveys. 4) We created a preliminary instrument with the items found most relevant and assessed its factorial validity, internal consistency and reliability (weighted kappa) over a two-week period among 138 physicians attending a CPD activity. Out of 72 potentially relevant instruments, 47 were analyzed. Of the 1218 items extracted from these, 16% were discarded as improperly phrased and 70% discarded as duplicates. Mapping the remaining items onto the constructs of the integrated model of healthcare professionals' behaviors yielded a minimum of 18 and a maximum of 275 items per construct. The partnership committee retained 61 items covering all seven constructs. Two iterations of the Delphi process produced consensus on a provisional 40-item questionnaire. Exploratory factorial analysis following test-retest resulted in a 12-item questionnaire. Cronbach's coefficients for the constructs varied from 0.77 to 0.85. Conclusion A 12-item theory-based instrument for assessing the impact of CPD activities on health professionals' clinical behavioral

  6. Influence of Martensite Volume Fraction on Impact Properties of Triple Phase (TP) Steels

    NASA Astrophysics Data System (ADS)

    Zare, Ahmad; Ekrami, A.

    2013-03-01

    Ferrite-bainite-martensite triple phase (TP) microstructures with different volume fractions of martensite were obtained by changing heat treatment time during austempering at 300 °C. Room temperature impact properties of TP steels with different martensite volume fractions ( V M) were determined by means of Charpy impact testing. The effects of test temperature on impact properties were also investigated for two selected microstructures containing 0 (the DP steel) and 8.5 vol.% martensite. Test results showed reduction in toughness with increasing V M in TP steels. Fracture toughness values for the DP and TP steels with 8.5 vol.% martensite were obtained from correlation between fracture toughness and the Charpy impact energy. Fractography of Charpy specimens confirmed decrease in TP steels' toughness with increasing V M by considering and comparing radial marks and crack initiation regions at the fracture surfaces of the studied steels.

  7. Generic analyses for evaluation of low Charpy upper-shelf energy effects on safety margins against fracture of reactor pressure vessel materials

    SciTech Connect

    Dickson, T.L.

    1993-07-01

    Appendix G to 10 CFR Part 50 requires that reactor pressure vessel beltline material maintain Charpy upper-shelf energies of no less than 50 ft-lb during the plant operating life, unless it is demonstrated in a manner approved by the Nuclear Regulatory Commission (NRC), that lower values of Charpy upper-shelf energy provide margins of safety against fracture equivalent to those in Appendix G to Section XI of the ASME Code. Analyses based on acceptance criteria and analysis methods adopted in the ASME Code Case N-512 are described herein. Additional information on material properties was provided by the NRC, Office of Nuclear Regulatory Research, Materials Engineering Branch. These cases, specified by the NRC, represent generic applications to boiling water reactor and pressurized water reactor vessels. This report is designated as HSST Report No. 140.

  8. The Impact of Withholding Observations from TOMS or SBUV Instruments on the GEOS Ozone Data Assimilation System

    NASA Technical Reports Server (NTRS)

    Stajner, Ovanka; Riishojgaard, Lars Peter; Rood, Richard B.

    2000-01-01

    In a data assimilation system (DAS), model forecast atmospheric fields, observations and their respective statistics are combined in an attempt to produce the best estimate of these fields. Ozone observations from two instruments are assimilated in the Goddard Earth Observing System (GEOS) ozone DAS: the Total Ozone Mapping Spectrometer (TOMS) and the Solar Backscatter Ultraviolet (SBUV) instrument. The assimilated observations are complementary; TOMS provides a global daily coverage of total column ozone, without profile information, while SBUV measures ozone profiles and total column ozone at nadir only. The purpose of this paper is to examine the performance of the ozone assimilation system in the absence of observations from one of the instruments as it can happen in the event of a failure of an instrument or when there are problems with an instrument for a limited time. Our primary concern is for the performance of the GEOS ozone DAS when it is used in the operational mode to provide near real time analyzed ozone fields in support of instruments on the Terra satellite. In addition, we are planning to produce a longer term ozone record by assimilating historical data. We want to quantify the differences in the assimilated ozone fields that are caused by the changes in the TOMS or SBUV observing network. Our primary interest is in long term and large scale features visible in global statistics of analysis fields, such as differences in the zonal mean of assimilated ozone fields or comparisons with independent observations, While some drifts in assimilated fields occur immediately, after assimilating just one day of different observations, the others develop slowly over several months. Thus, we are also interested in the length of time, which is determined from time series, that is needed for significant changes to take place.

  9. Investigating the Impact of Formal Reflective Activities on Skill Adaptation in a Work-Related Instrumental Learning Setting

    ERIC Educational Resources Information Center

    Roessger, Kevin M.

    2013-01-01

    In work-related, instrumental learning contexts the role of reflective activities is unclear. Kolb's (1985) experiential learning theory and Mezirow's transformative learning theory (2000) predict skill-adaptation as a possible outcome. This prediction was experimentally explored by manipulating reflective activities and assessing participants'…

  10. Investigation of the impact of instrumental and software applications on cotton and botanical trash identification by ultraviolet-visible spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Given the worldwide production, usage, and manufacturing of cotton, protocols that could identify botanical cotton trash components which can become comingled with cotton could be advantageous for quality assessment prior to spinning. Conventional methods such as the High Volume Instrument (HVITM) o...

  11. Impact of scatter on double-pass image quality and contrast sensitivity measured with a single instrument

    PubMed Central

    Bueno, Juan M.; Pérez, Guillermo; Benito, Antonio; Artal, Pablo

    2015-01-01

    We compared objective Double-Pass (DP) image quality data with subjective visual parameters measured within the same modified instrument for different amounts of scatter. The original DP imaging channel of a clinical instrument was maintained intact and two additional channels were included, one for visual testing and another for tear film (TF) imaging by using a retro-illumination technique. Contrast sensitivity (CS) was compared with measurements of the Objective Scattering Index (OSI) obtained from DP retinal images corresponding to different scatter levels induced by pre-defined filters. OSI values were correlated with the change in CS for different spatial frequencies measured with the same instrument. Since TF and DP images were recorded at the same rate, this provided additional information about the dynamic spatial stability of the tear film. This new DP instrument has been proven to provide accuracy and repeatability, and to be suitable for clinical diagnosis, with a complete evaluation of the eye’s performance by a simultaneous objective and subjective assessment under the same experimental conditions. PMID:26713198

  12. Impact of scatter on double-pass image quality and contrast sensitivity measured with a single instrument.

    PubMed

    Bueno, Juan M; Pérez, Guillermo; Benito, Antonio; Artal, Pablo

    2015-12-01

    We compared objective Double-Pass (DP) image quality data with subjective visual parameters measured within the same modified instrument for different amounts of scatter. The original DP imaging channel of a clinical instrument was maintained intact and two additional channels were included, one for visual testing and another for tear film (TF) imaging by using a retro-illumination technique. Contrast sensitivity (CS) was compared with measurements of the Objective Scattering Index (OSI) obtained from DP retinal images corresponding to different scatter levels induced by pre-defined filters. OSI values were correlated with the change in CS for different spatial frequencies measured with the same instrument. Since TF and DP images were recorded at the same rate, this provided additional information about the dynamic spatial stability of the tear film. This new DP instrument has been proven to provide accuracy and repeatability, and to be suitable for clinical diagnosis, with a complete evaluation of the eye's performance by a simultaneous objective and subjective assessment under the same experimental conditions. PMID:26713198

  13. Ten years of OMI observations: scientific highlights and impacts on the new generation of UV/VIS satellite instrumentation

    NASA Astrophysics Data System (ADS)

    Levelt, Pieternel; Veefkind, Pepijn; Bhartia, Pawan; Joiner, Joanna; Tamminen, Johanna; OMI Science Team

    2014-05-01

    On July 15, 2004 Ozone Monitoring Instrument (OMI) was successfully launched from the Vandenberg military air force basis in California, USA, on NASA's EOS-Aura spacecraft. OMI is the first of a new generation of UV/VIS nadir solar backscatter imaging spectrometers, which provides nearly global coverage in one day with an unprecedented spatial resolution of 13 x 24 km2. OMI measures solar irradiance and Earth radiances in the wavelength range of 270 to 500 nm with a spectral resolution of about 0.5 nm. OMI is designed and built by the Netherlands and Finland and is also a third party mission of ESA. The major step that was made in the OMI instrument compared to its predecessors is the use of 2-dimensional detector arrays (CCDs) in a highly innovative small optical design. These innovations enable the combination of a high spatial resolution and a good spectral resolution with daily global coverage. OMI measures a range of trace gases (O3, NO2, SO2, HCHO, BrO, OClO, H2O), clouds and aerosols. Albeit OMI is already 5 years over its design lifetime, the instrument is still fully operational. The successor of OMI is TROPOMI (TROPOspheric Monitoring Instrument) on the Copernicus Sentinel-5 precursor mission, planned for launch in 2015. OMI's unique capabilities rely in measuring tropospheric trace gases with a small footprint and daily global coverage. The unprecedented spatial resolution of the instrument revealed for the first time tropospheric pollution maps on a daily basis with urban scale resolution leading to improved air quality forecasts. The OMI measurements also improve our understanding of air quality and the interaction between air quality and climate change by combining measurements of air pollutants and aerosols. In recent years the data are also used for obtaining high-resolution global emission maps using inverse modelling or related techniques, challenging the bottom-up inventories based emission maps. In addition to scientific research, OMI also

  14. LBL's Pollution Instrumentation Comparability Program.

    ERIC Educational Resources Information Center

    McLaughlin, R. D.; And Others

    1979-01-01

    Contained are condensed excerpts from the Lawrence Berkeley Laboratory Survey of Instrumentation for Environmental Monitoring. The survey describes instrumentation used to analyze air and water quality, radiation emissions, and biomedical impacts. (BB)

  15. Gyroscopic Instruments for Instrument Flying

    NASA Technical Reports Server (NTRS)

    Brombacher, W G; Trent, W C

    1938-01-01

    The gyroscopic instruments commonly used in instrument flying in the United States are the turn indicator, the directional gyro, the gyromagnetic compass, the gyroscopic horizon, and the automatic pilot. These instruments are described. Performance data and the method of testing in the laboratory are given for the turn indicator, the directional gyro, and the gyroscopic horizon. Apparatus for driving the instruments is discussed.

  16. Measuring Research Quality Using the Journal Impact Factor, Citations and "Ranked Journals": Blunt Instruments or Inspired Metrics?

    ERIC Educational Resources Information Center

    Jarwal, Som D.; Brion, Andrew M.; King, Maxwell L.

    2009-01-01

    This paper examines whether three bibliometric indicators--the journal impact factor, citations per paper and the Excellence in Research for Australia (ERA) initiative's list of "ranked journals"--can predict the quality of individual research articles as assessed by international experts, both overall and within broad disciplinary groupings. The…

  17. The Use of MODIS Instrument on the EOS-Terra Satellite to Assess the Impact of Aerosol on Climate

    NASA Technical Reports Server (NTRS)

    Kaufman, Y.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    Terra will derive the aerosol optical thickness and properties. The aerosol properties can be used to distinguish between natural and human-made aerosol. In the polar orbit Terra will measure aerosol only once a day, around 10:30 am. How will we use this information to study the global radiative impacts of aerosol on climate? We shall present a strategy to address this problem. It includes the following steps: 1) From the Terra aerosol optical thickness and size distribution model we derive the effect of aerosol on reflection of solar radiation at the top of the atmosphere. In a sensitivity study we show that the effect of aerosol on solar fluxes can be derived 10 times more accurately from the MODIS data than derivation of the optical thickness itself. Applications to data over several regions will be given. 2) Using 1/2 million AERONET global data of aerosol spectral optical thickness we show that the aerosol optical thickness and properties during the Terra 10:30 pass are equivalent to the daily average. Due to the aerosol lifetime of several days measurements at this time of the day are enough to assess the daily impact of aerosol on radiation. 3) Aerosol impact on the top of the atmosphere is only part of the climate question. The INDOEX experiment showed that addressing the impact of aerosol on climate, requires also measurements of the aerosol forcing at the surface. This can be done by a combination of measurements of MODIS and AERONET data.

  18. Development and validation of an instrument to measure the impact of genetic testing on self-concept in Lynch syndrome.

    PubMed

    Esplen, M J; Stuckless, N; Gallinger, S; Aronson, M; Rothenmund, H; Semotiuk, K; Stokes, J; Way, C; Green, J; Butler, K; Petersen, H V; Wong, J

    2011-11-01

    A positive genetic test result may impact on a person's self-concept and affect quality of life. The purpose of the study was to develop a self-concept scale to measure such impact for individuals carrying mutations for a heritable colorectal cancer Lynch syndrome (LS). Two distinct phases were involved: Phase 1 generated specific colorectal self-concept candidate scale items from interviews with eight LS carriers and five genetic counselors, which were added to a previously developed self-concept scale for BRCA1/2 mutation carriers, Phase II had 115 LS carriers complete the candidate scale and a battery of validating measures. A 20-item scale was developed with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale showed excellent reliability (Cronbach's α = 0.93), good convergent validity by a high correlation with impact of event scale (r(102) = 0.55, p < 0.001) and Rosenberg self-esteem scale (r(108) = -0.59, p < 0.001), and a low correlation with the Fear questionnaire (r(108) = 0.37, p < 0.001). The scale's performance was stable across participant characteristics. This new scale for measuring self-concept has potential to be used as a clinical tool and as a measure for future studies. PMID:21883167

  19. Impact of length of stay after coronary bypass surgery on short-term readmission rate: An instrumental variable analysis

    PubMed Central

    Li, Yue; Cai, Xueya; Mukamel, Dana B.; Cram, Peter

    2012-01-01

    Objective To determine the effect of postoperative length of stay on 30-day readmission after coronary artery bypass surgery. Data Sources/Study Setting We analyzed a final database consisting of Medicare claims of a cohort (N=157,070) of all fee-for-service beneficiaries undergoing bypass surgery during 2007-2008, the American Hospital Association annual survey file, and the rural urban commuting area file. Study Design We regressed the probability of 30-day readmission on postoperative length of stay using (1) a (naïve) logit model that controlled for observed patient and hospital covariates only; and (2) a residual inclusion instrumental variable (IV) logit model that further controlled for unobserved confounding. The IV was defined using a measure of the hospital’s risk-adjusted length of stay for patients admitted for gastrointestinal hemorrhage. Principal Findings The naïve logit model predicted that a one-day reduction in median post-operative length of stay (i.e. from a median of 6 days to 5 days) lowered the 30-day readmission rate by 2 percentage points. The IV model predicted that a one-day reduction in median post-operative length of stay increased 30-day readmission rate by 3 percentage points. Conclusions The findings indicate that a reduction in postoperative length of stay is associated with an increased risk for 30-day readmission among Medicare patients undergoing bypass surgery, after both observed and unobserved confounding effects are corrected. PMID:23032357

  20. Instrument performance evaluation

    SciTech Connect

    Swinth, K.L.

    1993-03-01

    Deficiencies exist in both the performance and the quality of health physics instruments. Recognizing the implications of such deficiencies for the protection of workers and the public, in the early 1980s the DOE and the NRC encouraged the development of a performance standard and established a program to test a series of instruments against criteria in the standard. The purpose of the testing was to establish the practicality of the criteria in the standard, to determine the performance of a cross section of available instruments, and to establish a testing capability. Over 100 instruments were tested, resulting in a practical standard and an understanding of the deficiencies in available instruments. In parallel with the instrument testing, a value-impact study clearly established the benefits of implementing a formal testing program. An ad hoc committee also met several times to establish recommendations for the voluntary implementation of a testing program based on the studies and the performance standard. For several reasons, a formal program did not materialize. Ongoing tests and studies have supported the development of specific instruments and have helped specific clients understand the performance of their instruments. The purpose of this presentation is to trace the history of instrument testing to date and suggest the benefits of a centralized formal program.

  1. Low temperature impact toughness of the main gas pipeline steel after long-term degradation

    NASA Astrophysics Data System (ADS)

    Maruschak, Pavlo O.; Danyliuk, Iryna M.; Bishchak, Roman T.; Vuherer, Tomaž

    2014-12-01

    The correlation of microstructure, temperature and Charpy V-notch impact properties of a steel 17G1S pipeline steel was investigated in this study. Within the concept of physical mesomechanics, the dynamic failure of specimens is represented as a successive process of the loss of shear stability, which takes place at different structural/scale levels of the material. Characteristic stages are analyzed for various modes of failure, moreover, typical levels of loading and oscillation periods, etc. are determined. Relations between low temperature derived through this test, microstructures and Charpy (V-notch) toughness test results are also discussed in this paper.

  2. Impact of pigmentary disorders on quality of life in Japan: Interest of the BeautyQoL instrument.

    PubMed

    Beresniak, Ariel; Auray, Jean-Paul; Duru, Gérard; Aractingi, Selim; Krueger, Gerald G; Talarico, Sergio; Adam, Anne-Sophie; Piot, Bertrand; Dupont, Danielle; de Linares, Yolaine

    2015-01-01

    Skin pigmentary disorders and uneven skin tone represent common cosmetic concerns in Japan where fairer skin is culturally desirable. As the demographics of Asian countries continue to evolve, there is a need to understand the impact of cosmetic skin concerns on quality of life (QoL). 199 Japanese women self-claiming facial skin pigmentation disorders were asked to complete the BeautyQoL questionnaire, and the results were compared with those of a control group of 200 women. Of the five dimensions of the BeautyQoL questionnaire, the dimension "mood" appeared to be significantly lower in the group presenting facial dark spots, as compared with the control group (p < 0.05). In the group presenting facial dark spots, the five dimensions and the global score showed that subjects concerned had lower scores than subjects less concerned, even if statistical significance was not reached. This study confirms that common pigmentary disorders such as facial black spots may negatively impact QoL. Further comparative studies with a controlled randomized design would be necessary to confirm these findings. PMID:25968164

  3. A new instrument to measure charged and neutral cometary dust particles at low and high impact velocities

    NASA Technical Reports Server (NTRS)

    Economon, T.; Simpson, J. A.; Tuzzolino, A. J.

    1986-01-01

    A new class of dust particle detector, the PVDF dust detector, was designed for space missions such as the Halley Comet missions where the particle impact velocity is very high. It is demonstrated that this same PVDF detector (operating in a different mode) also has the capability of detecting dust particles having low velocity (approx. 100 m/s). This low velocity detection capability is extremely important in terms of planned missions requiring measurement of low velocity dust particles such as comet rendezvous missions. An additional detecting element (charge induction cylinder) was also developed which, when combined with a PVDF detector, yields a system which will measure the charge (magnitude and sign) carried by a cometary particle as well as the particle velocity and mass for impact velocities in the range 100 to 500 m/s. Since the cylinder-PVDF detector system has a relatively small geometry factors, an array of PVDF detectors was included having a total sensing area of 0.1 sq m for measurements in regions of space where the dust flux is expected to be low. The characteristics of the detectors in this array have been chosen to provide optimum mass sensitivity for both low-velocity cometary dust as well as high-velocity asteroid associated and interplanetary dust.

  4. Micron-sized-particle impacts detected near Uranus by the Voyager 2 plasma-wave instrument. Progress report for period ending 1986

    SciTech Connect

    Gurnett, D.A.; Kurth, W.S.; Scarf, F.L.; Burns, J.A.; Cuzzi, J.N.

    1986-12-22

    During the Voyager 2 flyby of Uranus, the plasma-wave and radio-astronomy instruments detected a region of impulsive noise near the equatorial plane just inside the orbit of Miranda, at a radial distance of 4.51 RU. This noise is believed to be caused by micrometer-sized particles hitting the spacecraft. Analysis of various coupling mechanisms shows that when a dust particle is instantly vaporized and ionized, thereby releasing a cloud of charged particles, some are collected by the antenna. The resulting voltage pulse is detected by the plasma-wave instrument. Based on reasonable assumptions about the charge yield and collection efficiency of the antenna, the number density and mass of the particles can be estimated from the rate and amplitude of the voltage pulses. The analysis shows that the maximum number density of the particles is about .0016/cwm, and the thickness of the impact region, based on a Gaussian fit, is 3480 km. The maximum number density occurs slightly after the ring-plane crossing at a distance of about 280 km from the equatorial plane. Possible sources for these particles include the rings, the small satellite 1985U1 discovered outside the ring system, or other unseen small bodies that lie between synchronous orbit (3.15 RU) and 4.51 RU. If the particles are charged, electromagnetic forces produced by the rotating tilted dipole of Uranus may play a role in their transport and diffusion.

  5. Simulation visualization through dynamic instrumentation

    SciTech Connect

    Bisset, K.R.

    1998-09-01

    The goal of the instrument composition system is to allow a simulation user to dynamically create instruments as a simulation executes. Instruments can include graphical displays, data collectors, and debugging aides. Instruments are made up of small building blocks which can be easily combined into larger, more complex instruments. Through the sue of an Attribute Server (a distributed publication/subscription mechanism), the actors and instruments in a simulation can interact without direct knowledge of each other. Instead, each actor publishes the attributes which it has available. An instrument subscribes to the attributes in which it is interested, and is notified whenever the value of one of these attribute changes. An instrument can also publish attributes for use by other instruments. Since the Attribute Server is distributed, the publisher of an attribute need not execute on the same machine as the subscriber. This allows CPU intensive data visualization to execute on separate machines from the simulation, minimizing the impact on the simulation.

  6. Monitoring Instruments

    ERIC Educational Resources Information Center

    Environmental Science and Technology (Environmental Control Issue), 1977

    1977-01-01

    This section contains a listing of the manufacturers of environmental monitoring instruments. The manufacturers are listed alphabetically under product headings. Addresses are included in a different section. (MA)

  7. Cordless Instruments

    NASA Astrophysics Data System (ADS)

    1981-01-01

    Black & Decker's new cordless lightweight battery powered precision instruments, adapted from NASA's Apollo Lunar Landing program, have been designed to give surgeons optimum freedom and versatility in the operating room. Orthopedic instrument line includes a drill, a driver/reamer and a sagittal saw. All provide up to 20 minutes on a single charge. Power pack is the instrument's handle which is removable for recharging. Microprocessor controlled recharging unit can recharge two power packs together in 30 minutes. Instruments can be gas sterilized, steam-sterilized in an autoclave or immersed for easy cleaning.

  8. Prevalence and impact of premature ejaculation in outpatients complaining of ejaculating prematurely: using the instruments of intravaginal ejaculatory latency time and patient-reported outcome measures.

    PubMed

    Gao, J; Zhang, X; Su, P; Shi, K; Tang, D; Hao, Z; Zhou, J; Liang, C

    2014-01-01

    This study was designed to assess the impact of premature ejaculation (PE) on a large population of men and their female partners using the instruments of intravaginal ejaculatory latency time (IELT) and patient-reported outcome (PRO) measures. A non-interventional, observational and cross-sectional field survey enrolled 2704 men with self-reported PE and their female partners from January 2010 to January 2012. PE was diagnosed by the International Society for Sexual Medicine (ISSM) criterion. IELT and sexual dysfunction were measured using a stopwatch and PRO measures, respectively. The incidence of PE in this study was 19.27%. PE negatively impacted on subjects and their partners, including reduced ejaculatory control and sexual satisfaction, and increased personal distress and interpersonal difficulty (P<0.001 for all). The severity of PE was considered worse by subjects than by their female partners (P<0.001). Reduced ejaculatory control and sexual satisfaction were considered the central themes of PE. Furthermore, a correlation was observed among the outcomes of IELT and PRO measures for subjects and their partners (absolute correlation coefficient ranged from 0.33 to 0.67). This in-depth qualitative study provides valuable insight into the PE status in Chinese men. Further research is needed to confirm and extend these results. PMID:24384563

  9. Impact of cloud horizontal inhomogeneity and directional sampling on the retrieval of cloud droplet size by the POLDER instrument

    NASA Astrophysics Data System (ADS)

    Shang, H.; Chen, L.; Bréon, F. M.; Letu, H.; Li, S.; Wang, Z.; Su, L.

    2015-11-01

    The principles of cloud droplet size retrieval via Polarization and Directionality of the Earth's Reflectance (POLDER) requires that clouds be horizontally homogeneous. The retrieval is performed by combining all measurements from an area of 150 km × 150 km to compensate for POLDER's insufficient directional sampling. Using POLDER-like data simulated with the RT3 model, we investigate the impact of cloud horizontal inhomogeneity and directional sampling on the retrieval and analyze which spatial resolution is potentially accessible from the measurements. Case studies show that the sub-grid-scale variability in droplet effective radius (CDR) can significantly reduce valid retrievals and introduce small biases to the CDR (~ 1.5 μm) and effective variance (EV) estimates. Nevertheless, the sub-grid-scale variations in EV and cloud optical thickness (COT) only influence the EV retrievals and not the CDR estimate. In the directional sampling cases studied, the retrieval using limited observations is accurate and is largely free of random noise. Several improvements have been made to the original POLDER droplet size retrieval. For example, measurements in the primary rainbow region (137-145°) are used to ensure retrievals of large droplet (> 15 μm) and to reduce the uncertainties caused by cloud heterogeneity. We apply the improved method using the POLDER global L1B data from June 2008, and the new CDR results are compared with the operational CDRs. The comparison shows that the operational CDRs tend to be underestimated for large droplets because the cloudbow oscillations in the scattering angle region of 145-165° are weak for cloud fields with CDR > 15 μm. Finally, a sub-grid-scale retrieval case demonstrates that a higher resolution, e.g., 42 km × 42 km, can be used when inverting cloud droplet size distribution parameters from POLDER measurements.

  10. SURVEY INSTRUMENT

    DOEpatents

    Borkowski, C J

    1954-01-19

    This pulse-type survey instrument is suitable for readily detecting {alpha} particles in the presence of high {beta} and {gamma} backgrounds. The instruments may also be used to survey for neutrons, {beta} particles and {gamma} rays by employing suitably designed interchangeable probes and selecting an operating potential to correspond to the particular probe.

  11. Improved impact-resistant boron/aluminum composites for use as turbine engine fan blades

    NASA Technical Reports Server (NTRS)

    Mcdanels, D. L.; Signorelli, R. A.

    1976-01-01

    Thin-sheet Charpy and Izod impact tests and standard full-size Charpy impact tests were conducted on unidirectional and angleply composites containing 4, 5.6 and 8 mil boron in 1100, 2024, 5052 and 6061 Al matrices. Impact failure modes of B/Al are proposed to describe the mechanisms involved and to provide insight for maximizing impact resistance. The impact strength of B/Al was significantly increased by proper selection of materials and processing. The use of more ductile matrices and larger diameter boron fibers gave the highest impact strengths by allowing matrix shear deformation and multiple fiber breakage. Pendulum impact test results of improved B/Al were higher than notched titanium and indicate sufficient foreign object damage protection to warrant consideration of B/Al for application to fan blades in aircraft gas turbine engines.

  12. Effect of fiber diameter and matrix alloys on impact-resistant boron/aluminum composites

    NASA Technical Reports Server (NTRS)

    Mcdanels, D. L.; Signorelli, R. A.

    1976-01-01

    Efforts to improve the impact resistance of B/Al are reviewed and analyzed. Nonstandard thin-sheet charpy and Izod impact tests and standard full-size Charpy impact tests were conducted on composites containing unidirectional 0.10mm, 0.14mm, and 0.20mm diameter boron fibers in 1100, 2024, 5052, and 6061 Al matrices. Impact failure modes of B/Al are proposed in an attempt to describe the mechanisms involved and to provide insight for maximizing impact resistance. The impact strength of B/Al was significantly increased by proper selection of materials and processing. The use of a ductile matrix and large diameter boron fibers gave the highest impact strengths. This combination resulted in improved energy absorption through matrix shear deformation and multiple fiber breakage.

  13. Improved impact-resistant boron-aluminum composites for use as turbine engine fan blades

    NASA Technical Reports Server (NTRS)

    Mcdanels, D. L.; Signorelli, R. A.

    1976-01-01

    Efforts to improve the impact resistance of B/Al are reviewed and analyzed. Thin sheet Charpy and Izod impact tests and standard full size Charpy impact tests were conducted on unidirectional and angleply composites containing 4, 5.6 and 8 mil boron in 1100, 2024, 5052 and 6061 Al matrices. Impact failure modes of B/Al are proposed in an attempt to describe the mechanisms involved and to provide insight for maximizing impact resistance. The impact strength of B/Al was significantly increased by proper selection of materials and processing. The use of more ductile matrices (1100 Al) and larger diameter (8 mil) boron fibers gave the highest impact strengths by allowing matrix shear deformation and multiple fiber breakage.

  14. Fractographic examination of ferritic alloy Charpy specimens at a fluence of 6 x 10/sup 22/ n/cm/sup 2/

    SciTech Connect

    Gelles, D.S.; Hu, W.L.

    1985-05-01

    The fracture surfaces of thirteen Charpy specimens have been examined by scanning electron microscopy and several of these have been measured for hardness. The specimen series irradiated in the AD-2 test, second discharge includes HT-9 base metal in two product forms, and Modified 9Cr-1Mo base metal and weld metal, fluences include 13 and 26 dpa and irradiation temperatures cover the range 390/sup 0/C to 550/sup 0/C. Fracture appearance is found to be insensitive to irradiation fluence, whereas significant differences could be found in product form. It is concluded that irradiation does not encourage a new fracture mechanism such as temper embrittlement. Failure is controlled by the microstructure generated prior to irradiation.

  15. Instrumentation '79.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1979

    1979-01-01

    Surveys the state of commerical development of analytical instrumentation as reflected by the Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy. Includes optical spectroscopy, liquid chromatography, magnetic spectrometers, and x-ray. (Author/MA)

  16. Astronomical instruments.

    NASA Astrophysics Data System (ADS)

    Rai, R. N.

    Indian astronomers have devised a number of instruments and the most important of these is the armillary sphere. The earliest armillary spheres were very simple instruments. Ptolemy in his Almagest enumerates at least three. The simplest of all was the equinoctial armilla. They had also the solstitial armilla which was a double ring, erected in the plane of the meridian with a rotating inner circle. This was used to measure the solar altitude.

  17. Oceanographic Instrument

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Developed under NASA contract, the Fast Repetition Rate (FRR) fluorometer is a computer-controlled instrument for measuring the fluorescence of phytoplankton, microscopic plant forms that provide sustenance for animal life in the oceans. The fluorometer sensor is towed by ship through the water and the resulting printouts are compared with satellite data. The instrument is non-destructive and can be used in situ, providing scientific information on ocean activity and productivity.

  18. An Instrumental Variable Probit (IVP) analysis on depressed mood in Korea: the impact of gender differences and other socio-economic factors

    PubMed Central

    Gitto, Lara; Noh, Yong-Hwan; Andrés, Antonio Rodríguez

    2015-01-01

    Background: Depression is a mental health state whose frequency has been increasing in modern societies. It imposes a great burden, because of the strong impact on people’s quality of life and happiness. Depression can be reliably diagnosed and treated in primary care: if more people could get effective treatments earlier, the costs related to depression would be reversed. The aim of this study was to examine the influence of socio-economic factors and gender on depressed mood, focusing on Korea. In fact, in spite of the great amount of empirical studies carried out for other countries, few epidemiological studies have examined the socio-economic determinants of depression in Korea and they were either limited to samples of employed women or did not control for individual health status. Moreover, as the likely data endogeneity (i.e. the possibility of correlation between the dependent variable and the error term as a result of autocorrelation or simultaneity, such as, in this case, the depressed mood due to health factors that, in turn might be caused by depression), might bias the results, the present study proposes an empirical approach, based on instrumental variables, to deal with this problem. Methods: Data for the year 2008 from the Korea National Health and Nutrition Examination Survey (KNHANES) were employed. About seven thousands of people (N= 6,751, of which 43% were males and 57% females), aged from 19 to 75 years old, were included in the sample considered in the analysis. In order to take into account the possible endogeneity of some explanatory variables, two Instrumental Variables Probit (IVP) regressions were estimated; the variables for which instrumental equations were estimated were related to the participation of women to the workforce and to good health, as reported by people in the sample. Explanatory variables were related to age, gender, family factors (such as the number of family members and marital status) and socio-economic factors

  19. Instrumented SSH

    SciTech Connect

    Campbell, Scott; Campbell, Scott

    2009-05-27

    NERSC recently undertook a project to access and analyze Secure Shell (SSH) related data. This includes authentication data such as user names and key fingerprints, interactive session data such as keystrokes and responses, and information about noninteractive sessions such as commands executed and files transferred. Historically, this data has been inaccessible with traditional network monitoring techniques, but with a modification to the SSH daemon, this data can be passed directly to intrusion detection systems for analysis. The instrumented version of SSH is now running on all NERSC production systems. This paper describes the project, details about how SSH was instrumented, and the initial results of putting this in production.

  20. Research Instruments

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The GENETI-SCANNER, newest product of Perceptive Scientific Instruments, Inc. (PSI), rapidly scans slides, locates, digitizes, measures and classifies specific objects and events in research and diagnostic applications. Founded by former NASA employees, PSI's primary product line is based on NASA image processing technology. The instruments karyotype - a process employed in analysis and classification of chromosomes - using a video camera mounted on a microscope. Images are digitized, enabling chromosome image enhancement. The system enables karyotyping to be done significantly faster, increasing productivity and lowering costs. Product is no longer being manufactured.

  1. Geoscience instrumentation

    NASA Technical Reports Server (NTRS)

    Wolff, E. A. (Editor); Mercanti, E. P.

    1974-01-01

    Geoscience instrumentation systems are considered along with questions of geoscience environment, signal processing, data processing, and design problems. Instrument platforms are examined, taking into account ground platforms, airborne platforms, ocean platforms, and space platforms. In situ and laboratory sensors described include acoustic wave sensors, age sensors, atmospheric constituent sensors, biological sensors, cloud particle sensors, electric field sensors, electromagnetic field sensors, precision geodetic sensors, gravity sensors, ground constituent sensors, horizon sensors, humidity sensors, ion and electron sensors, magnetic field sensors, tide sensors, and wind sensors. Remote sensors are discussed, giving attention to sensing techniques, acoustic echo-sounders, gamma ray sensors, optical sensors, radar sensors, and microwave radiometric sensors.

  2. Interfacing to accelerator instrumentation

    SciTech Connect

    Shea, T.J.

    1995-12-31

    As the sensory system for an accelerator, the beam instrumentation provides a tremendous amount of diagnostic information. Access to this information can vary from periodic spot checks by operators to high bandwidth data acquisition during studies. In this paper, example applications will illustrate the requirements on interfaces between the control system and the instrumentation hardware. A survey of the major accelerator facilities will identify the most popular interface standards. The impact of developments such as isochronous protocols and embedded digital signal processing will also be discussed.

  3. Weather Instruments.

    ERIC Educational Resources Information Center

    Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.

    This booklet presents some activities to measure various weather phenomena. Directions for constructing a weather station are included. Instruments including rain gauges, thermometers, wind vanes, wind speed devices, humidity devices, barometers, atmospheric observations, a dustfall jar, sticky-tape can, detection of gases in the air, and pH of…

  4. RHIC instrumentation

    SciTech Connect

    Shea, T. J.; Witkover, R. L.

    1998-12-10

    The Relativistic Heavy Ion Collider (RHIC) consists of two 3.8 km circumference rings utilizing 396 superconducting dipoles and 492 superconducting quadrupoles. Each ring will accelerate approximately 60 bunches of 10{sup 11} protons to 250 GeV, or 10{sup 9} fully stripped gold ions to 100 GeV/nucleon. Commissioning is scheduled for early 1999 with detectors for some of the 6 intersection regions scheduled for initial operation later in the year. The injection line instrumentation includes: 52 beam position monitor (BPM) channels, 56 beam loss monitor (BLM) channels, 5 fast integrating current transformers and 12 video beam profile monitors. The collider ring instrumentation includes: 667 BPM channels, 400 BLM channels, wall current monitors, DC current transformers, ionization profile monitors (IPMs), transverse feedback systems, and resonant Schottky monitors. The use of superconducting magnets affected the beam instrumentation design. The BPM electrodes must function in a cryogenic environment and the BLM system must prevent magnet quenches from either fast or slow losses with widely different rates. RHIC is the first superconducting accelerator to cross transition, requiring close monitoring of beam parameters at this time. High space-charge due to the fully stripped gold ions required the IPM to collect magnetically guided electrons rather than the conventional ions. Since polarized beams will also be accelerated in RHIC, additional constraints were put on the instrumentation. The orbit must be well controlled to minimize depolarizing resonance strengths. Also, the position monitors must accommodate large orbit displacements within the Siberian snakes and spin rotators. The design of the instrumentation will be presented along with results obtained during bench tests, the injection line commissioning, and the first sextant test.

  5. RHIC instrumentation

    NASA Astrophysics Data System (ADS)

    Shea, T. J.; Witkover, R. L.

    1998-12-01

    The Relativistic Heavy Ion Collider (RHIC) consists of two 3.8 km circumference rings utilizing 396 superconducting dipoles and 492 superconducting quadrupoles. Each ring will accelerate approximately 60 bunches of 1011 protons to 250 GeV, or 109 fully stripped gold ions to 100 GeV/nucleon. Commissioning is scheduled for early 1999 with detectors for some of the 6 intersection regions scheduled for initial operation later in the year. The injection line instrumentation includes: 52 beam position monitor (BPM) channels, 56 beam loss monitor (BLM) channels, 5 fast integrating current transformers and 12 video beam profile monitors. The collider ring instrumentation includes: 667 BPM channels, 400 BLM channels, wall current monitors, DC current transformers, ionization profile monitors (IPMs), transverse feedback systems, and resonant Schottky monitors. The use of superconducting magnets affected the beam instrumentation design. The BPM electrodes must function in a cryogenic environment and the BLM system must prevent magnet quenches from either fast or slow losses with widely different rates. RHIC is the first superconducting accelerator to cross transition, requiring close monitoring of beam parameters at this time. High space-charge due to the fully stripped gold ions required the IPM to collect magnetically guided electrons rather than the conventional ions. Since polarized beams will also be accelerated in RHIC, additional constraints were put on the instrumentation. The orbit must be well controlled to minimize depolarizing resonance strengths. Also, the position monitors must accommodate large orbit displacements within the Siberian snakes and spin rotators. The design of the instrumentation will be presented along with results obtained during bench tests, the injection line commissioning, and the first sextant test.

  6. RHIC instrumentation

    SciTech Connect

    Shea, T.J.; Witkover, R.L.

    1998-12-01

    The Relativistic Heavy Ion Collider (RHIC) consists of two 3.8 km circumference rings utilizing 396 superconducting dipoles and 492 superconducting quadrupoles. Each ring will accelerate approximately 60 bunches of 10{sup 11} protons to 250 GeV, or 10{sup 9} fully stripped gold ions to 100 GeV/nucleon. Commissioning is scheduled for early 1999 with detectors for some of the 6 intersection regions scheduled for initial operation later in the year. The injection line instrumentation includes: 52 beam position monitor (BPM) channels, 56 beam loss monitor (BLM) channels, 5 fast integrating current transformers and 12 video beam profile monitors. The collider ring instrumentation includes: 667 BPM channels, 400 BLM channels, wall current monitors, DC current transformers, ionization profile monitors (IPMs), transverse feedback systems, and resonant Schottky monitors. The use of superconducting magnets affected the beam instrumentation design. The BPM electrodes must function in a cryogenic environment and the BLM system must prevent magnet quenches from either fast or slow losses with widely different rates. RHIC is the first superconducting accelerator to cross transition, requiring close monitoring of beam parameters at this time. High space-charge due to the fully stripped gold ions required the IPM to collect magnetically guided electrons rather than the conventional ions. Since polarized beams will also be accelerated in RHIC, additional constraints were put on the instrumentation. The orbit must be well controlled to minimize depolarizing resonance strengths. Also, the position monitors must accommodate large orbit displacements within the Siberian snakes and spin rotators. The design of the instrumentation will be presented along with results obtained during bench tests, the injection line commissioning, and the first sextant test. {copyright} {ital 1998 American Institute of Physics.}

  7. Impact on Neurological Recovery of Transforaminal Debridement and Interbody Fusion versus Transpedicular Decompression in Combination with Pedicle Screw Instrumentation for Treating Thoracic and Lumbar Spinal Tuberculosis

    PubMed Central

    Choovongkomol, Kongtush; Piyapromdee, Urawit; Leownorasate, Manoon

    2016-01-01

    Study Design Retrospective study. Purpose To compare the neurological outcome of transforaminal debridement and interbody fusion with transpedicular decompression for treatment of thoracic and lumbar spinal tuberculosis. Overview of Literature Few articles have addressed the impact of neurological recovery in patients with tuberculosis who were treated by two different operative methods via the posterior-only approach. Methods Clinical and radiographic results of one-stage posterior instrumented spinal fusion for treatment of tuberculous spondylodiscitis with neurological deficits were reviewed and analyzed from 2009 to 2013. The extensive (E) group consisted of patients who received transforaminal debridement and interbody fusion, whereas transpedicular decompression was performed on limited (L) group. Rapid recovery was improvement of at least one Frankel grade within 6 weeks after operation. Otherwise, it was slow recovery. Results All 39 patients had improved neurological signs. The median follow-up period was 24 months. Proportionately younger patients (under 65 years of age) received extensive surgery (15 of 18, 83.3% vs. 11 of 21, 52.4%; p=0.04). The mean operative time and blood loss in the group E were higher than in the group L (both p<0.01). With regard to type of procedure, especially at thoracic and thoracolumbar spine, patients who underwent extensive surgery had rapid neurological recovery significantly different from those of limited surgery (p=0.01; Relative Risk, 3.06; 95% Confidence Interval, 1.13 to 8.29). Conclusions Transforaminal debridement and interbody fusion provides more rapid neurological recovery in patients with thoracic and thoracolumbar spinal tuberculosis compared to transpedicular decompression. PMID:27340536

  8. Measuring the Impact of Students' Social Relations and Values: Validation of the Social-Relational Support for Education Instrument

    ERIC Educational Resources Information Center

    Vickers, Margaret; Finger, Linda; Barker, Katrina; Bodkin-Andrews, Gawaian

    2014-01-01

    A significant body of literature attests to the influence of social contexts on students' engagement with school. A review of this literature led to the construction of a self-report instrument designed to measure Social-Relational Support for Education (SRSE). The conceptual framework underlying the SRSE instrument focuses on the factors…

  9. Influence of Chemical Composition and Heat Treatment Condition on Impact Toughness of 15Cr Ferritic Creep Resistant Steel

    NASA Astrophysics Data System (ADS)

    Toda, Yoshiaki; Tohyama, Hideaki; Kushima, Hideaki; Kimura, Kazuhiro; Abe, Fujio

    Influences of chemical compositions, heat treatment and microstructure on impact toughness of 15Cr ferritic steel have been investigated. Charpy impact values of the furnace cooled steels were lower than 15J/cm2 at room temperature independent of chemical compositions. Drastic improvement in impact toughness has been attained by controlling the carbon and nitrogen contents, by the addition of nickel and by the increase in cooling rate after annealing. However, the effect of nickel on impact toughness strongly depends on carbon and nitrogen contents. Improvement in impact toughness of the 15Cr ferritic steel has not been explained by individual microstructural factors of grain size, distribution of precipitates, volume fraction of martensitic phase. It has been supposed that the increase in Charpy impact toughness of the 15Cr ferritic steel was attained by improvement in toughness of ferrite matrix itself.

  10. Impact Energy of Functionally Graded Steels in Crack Arrester Configuration

    NASA Astrophysics Data System (ADS)

    Nazari, A.; Aghazadeh Mohandesi, J.

    2010-10-01

    Charpy impact energy of functionally graded steels produced by electroslag remelting composed of graded ferrite and austenite layers together with bainite or martensite intermediate layer in the form of crack arrester configuration has been investigated. The results obtained in the present study indicate that the notch tip position with respect to bainite or martensite layer significantly affects the impact energy. The closer the notch tip to the tougher layer, the higher the impact energy of the composite due to increment of energy absorbed by plastic deformation zone ahead of the notch and vice versa. Empirical relationships have been determined to correlate the impact energy of functionally graded steels to the morphology of layers.

  11. Visualization of impact damaging of carbon/epoxy panels

    NASA Astrophysics Data System (ADS)

    Boccardi, Simone; Boffa, Natalino Daniele; Carlomagno, Giovanni Maria; Meola, Carosena; Ricci, Fabrizio

    2016-05-01

    This work is concerned with impact damaging of carbon/epoxy materials. Specimens of different thickness are herein considered, which involve several fibers orientations and stacking sequences. Impact tests are carried out at different energies with a modified Charpy pendulum. The specimen surface opposite to that struck by the impactor is viewed by an infrared imaging device. Then, a sequence of thermal images is acquired during each impact test. Through the temperature variations experienced by the specimen surface, post-processing of such images supplies the likely occurred damage. In addition, specimens are non-destructively evaluated with lock-in thermography to visualize any manufacturing defects, as well as impact damage.

  12. Pancreatitis Quality of Life Instrument: Development of a new instrument

    PubMed Central

    Bova, Carol; Barton, Bruce; Hartigan, Celia

    2014-01-01

    Objectives: The goal of this project was to develop the first disease-specific instrument for the evaluation of quality of life in chronic pancreatitis. Methods: Focus groups and interview sessions were conducted, with chronic pancreatitis patients, to identify items felt to impact quality of life which were subsequently formatted into a paper-and-pencil instrument. This instrument was used to conduct an online survey by an expert panel of pancreatologists to evaluate its content validity. Finally, the modified instrument was presented to patients during precognitive testing interviews to evaluate its clarity and appropriateness. Results: In total, 10 patients were enrolled in the focus groups and interview sessions where they identified 50 items. Once redundant items were removed, the 40 remaining items were made into a paper-and-pencil instrument referred to as the Pancreatitis Quality of Life Instrument. Through the processes of content validation and precognitive testing, the number of items in the instrument was reduced to 24. Conclusions: This marks the development of the first disease-specific instrument to evaluate quality of life in chronic pancreatitis. It includes unique features not found in generic instruments (economic factors, stigma, and spiritual factors). Although this marks a giant step forward, psychometric evaluation is still needed prior to its clinical use. PMID:26770703

  13. The Impacts of Intrusive Advising on the Persistence of First-Year Science, Technology, and Mathematics Students Identified Using a Risk Prediction Instrument

    ERIC Educational Resources Information Center

    Campbell, Matthew A.

    2013-01-01

    Set in a large, urban, public university, this study explores the use of an institutionally specific risk instrument developed to identify students who had a high risk of attrition and the effectiveness of subsequent interventions deployed through advising. Though implemented throughout the institution, this study identified control and treatment…

  14. Optical Instruments

    NASA Astrophysics Data System (ADS)

    1990-01-01

    Precision Lapping and Optical Co. has developed a wide variety of hollow retroreflector systems for applications involving the entire optical spectrum; they are, according to company literature, cheaper, more accurate, lighter and capable of greater size than solid prisms. Precision Lapping's major customers are aerospace and defense companies, government organizations, R&D and commercial instrument companies. For example, Precision Lapping supplies hollow retroreflectors for the laser fire control system of the Army's Abrams tank, and retroreflectors have been and are being used in a number of space tests relative to the Air Force's Strategic Defense Initiative research program. An example of a customer/user is Chesapeake Laser Systems, producer of the Laser Tracker System CMS-2000, which has applications in SDI research and industrial robotics. Another customer is MDA Scientific, Inc., manufacturer of a line of toxic gas detection systems used to monitor hazardous gases present in oil fields, refineries, offshore platforms, chemical plants, waste storage sites and other locations where gases are released into the environment.

  15. Similar head impact acceleration measured using instrumented ear patches in a junior rugby union team during matches in comparison with other sports.

    PubMed

    King, Doug A; Hume, Patria A; Gissane, Conor; Clark, Trevor N

    2016-07-01

    OBJECTIVE Direct impact with the head and the inertial loading of the head have been postulated as major mechanisms of head-related injuries, such as concussion. METHODS This descriptive observational study was conducted to quantify the head impact acceleration characteristics in under-9-year-old junior rugby union players in New Zealand. The impact magnitude, frequency, and location were collected with a wireless head impact sensor that was worn by 14 junior rugby players who participated in 4 matches. RESULTS A total of 721 impacts > 10g were recorded. The median (interquartile range [IQR]) number of impacts per player was 46 (IQR 37-58), resulting in 10 (IQR 4-18) impacts to the head per player per match. The median impact magnitudes recorded were 15g (IQR 12g-21g) for linear acceleration and 2296 rad/sec(2) (IQR 1352-4152 rad/sec(2)) for rotational acceleration. CONCLUSIONS There were 121 impacts (16.8%) above the rotational injury risk limit and 1 (0.1%) impact above the linear injury risk limit. The acceleration magnitude and number of head impacts in junior rugby union players were higher than those previously reported in similar age-group sports participants. The median linear acceleration for the under-9-year-old rugby players were similar to 7- to 8-year-old American football players, but lower than 9- to 12-year-old youth American football players. The median rotational accelerations measured were higher than the median and 95th percentiles in youth, high school, and collegiate American football players. PMID:26942267

  16. Radiological instrument

    SciTech Connect

    Kronenberg, S.; McLaughlin, W.L.; Seibentritt, C.R. Jr.

    1986-12-23

    An instrument is described for measuring radiation, particularly nuclear radiation, comprising: a radiation sensitive structure pivoted toward one end and including a pair of elongated solid members contiguously joined together along their length dimensions and having a common planar interface therebetween. One of the pairs of members is comprised of radiochromic material whose index of refraction changes due to anomolous dispersion as a result of being exposed to nuclear radiation. The pair of members further has mutually different indices of refraction with the member having the larger index of refraction further being transparent for the passage of light and of energy therethrough; means located toward the other end of the structure for varying the angle of longitudinal elevation of the pair of members; means for generating and projecting a beam of light into one end of the member having the larger index of refraction. The beam of light is projected toward the planar interface where it is reflected out of the other end of the same member as a first output beam; means projecting a portion of the beam of light into one end of the member having the larger index of refraction where it traverses therethrough without reflection and out of the other end of the same member as a second output beam; and means adjacent the structure for receiving the first and second output beams, whereby a calibrated change in the angle of elevation of the structure between positions of equal intensity of the first and second output beams prior to and following exposure provides a measure of the radiation sensed due to a change of refraction of the radiochromic material.

  17. Spectroscopic Instruments

    NASA Astrophysics Data System (ADS)

    Kunze, Hans-Joachim

    The selection of a spectrographic system including the detector is governed by several aspects: - Wavelength region of interest - Low or high-resolution studies, survey spectra, line intensities only or detailed line profiles - Weak or strong emitter, which usually is equivalent to having a plasma of low or high density - Low or high time resolution, which basically determines the detector and only to a lesser degree the throughput of the system - Stigmatic or astigmatic image of the plasma in the exit plane Spectrometers with the exception of instruments for the X-ray region typically consist of: - An entrance slit (width w en, area A E) - A dispersive element - An optical system, which forms a spectrally dispersed image of the entrance slit in the exit plane - A detector in the exit plane Figure 3.1 illustrates a schematic layout. Dispersing elements are prisms, gratings, interferometers, and crystals. The imaging system consists usually of a lens L1 (or mirror M1) collimating the radiation from the entrance slit, and a lens L2 (or mirror M2) focusing the radiation in the exit (image) plane. Mirrors have the advantage of no chromatic aberration and can also be used at shorter wavelengths where glasses, quartz, and crystals absorb the radiation. Unfortunately, their reflectivity decreases at short wavelengths; this can be remedied to some degree by reducing the number of reflecting surfaces and employing spherical or even toroidal gratings which combine focusing and dispersing properties. The optical system (L1, L2) or (M1, M2) becomes unnecessary.

  18. Design and performance of an instrument for electron impact tandem mass spectrometry and action spectroscopy of mass/charge selected macromolecular ions stored in RF ion trap*

    NASA Astrophysics Data System (ADS)

    Ranković, Milos Lj.; Giuliani, Alexandre; Milosavljević, Aleksandar R.

    2016-06-01

    A new apparatus was designed, coupling an electron gun with a linear quadrupole ion trap mass spectrometer, to perform m/ z (mass over charge) selected ion activation by electron impact for tandem mass spectrometry and action spectroscopy. We present in detail electron tracing simulations of a 300 eV electron beam inside the ion trap, design of the mechanical parts, electron optics and electronic circuits used in the experiment. We also report examples of electron impact activation tandem mass spectra for Ubiquitin protein, Substance P and Melittin peptides, at incident electron energies in the range from 280 eV to 300 eV.

  19. Development of Procedures and Instruments for Assessing the Productivity and Impact of Post-Secondary Cooperative Education and Work Experience Programs. Final Report.

    ERIC Educational Resources Information Center

    Blaschke, Charles L.; And Others

    A project was conducted to assess the evaluation needs of post secondary cooperative education program administrators and to develop procedures and checklists for assessing productivity and impact of postsecondary cooperative education. This work built upon a general design developed in 1976 under part C of Public Law 90-576 for improving…

  20. Low activated incore instrument

    DOEpatents

    Ekeroth, D.E.

    1994-04-19

    Instrumentation is described for nuclear reactor head-mounted incore instrumentation systems fabricated of low nuclear cross section materials (i.e., zirconium or titanium). The instrumentation emits less radiation than that fabricated of conventional materials. 9 figures.

  1. Factors affecting miniature Izod impact strength of tungsten-fiber-metal-matrix

    NASA Technical Reports Server (NTRS)

    Winsa, E. A.; Petrasek, D. W.

    1973-01-01

    The miniature Izod and Charpy impact strengths of copper, copper-nickel, and nickel-base superalloy uniaxially reinforced with continuous tungsten fibers were studied. In most cases, impact strength was increased by increasing fiber or matrix toughness, decreasing fibermatrix reaction, increasing test temperature, hot working, or heat treating. Notch sensitivity was reduced by increasing fiber content or matrix toughness. An equation relating impact strength to fiber and matrix properties and fiber content was developed. Program results imply that tungsten alloy-fiber/superalloy matrix composites can be made with adequate impact resistance for turbine blade or vane applications.

  2. Evaluating musical instruments

    SciTech Connect

    Campbell, D. Murray

    2014-04-01

    Scientific measurements of sound generation and radiation by musical instruments are surprisingly hard to correlate with the subtle and complex judgments of instrumental quality made by expert musicians.

  3. Wasteful waste-reducing policies? The impact of waste reduction policy instruments on collection and processing costs of municipal solid waste.

    PubMed

    De Jaeger, Simon; Eyckmans, Johan; Rogge, Nicky; Van Puyenbroeck, Tom

    2011-07-01

    We study the impact of some local policies aimed at municipal solid waste (MSW) reduction on the cost efficiency of MSW collection and disposal. We explicitly account for differences between municipalities in background conditions by using a bootstrapped version of the Data Envelopment Analysis methodology in combination with a matching technique. Using data on 299 municipalities in Flanders, Belgium, for the year 2003, our results indicate that municipalities that are member of a waste collection joint venture, or that subscribe to a voluntary agreement to reduce MSW at the highest ambition level, collect and process MSW more efficiently than other municipalities. Weekly instead of two-weekly waste collection, or using a weight-based pricing system appears to have no impact on efficiency. Our results show that aiming at MSW reduction does not lead to lower efficiency of public service provision, even on the contrary. PMID:21429732

  4. Design and performance of an instrument for electron impact tandem mass spectrometry and action spectroscopy of mass/charge selected macromolecular ions stored in RF ion trap*

    NASA Astrophysics Data System (ADS)

    Ranković, Milos Lj.; Giuliani, Alexandre; Milosavljević, Aleksandar R.

    2016-05-01

    A new apparatus was designed, coupling an electron gun with a linear quadrupole ion trap mass spectrometer, to perform m/z (mass over charge) selected ion activation by electron impact for tandem mass spectrometry and action spectroscopy. We present in detail electron tracing simulations of a 300 eV electron beam inside the ion trap, design of the mechanical parts, electron optics and electronic circuits used in the experiment. We also report examples of electron impact activation tandem mass spectra for Ubiquitin protein, Substance P and Melittin peptides, at incident electron energies in the range from 280 eV to 300 eV. Contribution to the Topical Issue "Advances in Positron and Electron Scattering", edited by Paulo Limao-Vieira, Gustavo Garcia, E. Krishnakumar, James Sullivan, Hajime Tanuma and Zoran Petrovic.

  5. Formation Flying and Deformable Instruments

    SciTech Connect

    Rio, Yvon

    2009-05-11

    Astronomers have always attempted to build very stable instruments. They fight all that can cause mechanical deformation or image motion. This has led to well established technologies (autoguide, active optics, thermal control, tip/tilt correction), as well as observing methods based on the use of controlled motion (scanning, micro scanning, shift and add, chopping and nodding). Formation flying disturbs this practice. It is neither possible to reduce the relative motion to very small amplitudes, nor to control it at will. Some impacts on Simbol-X instrument design, and operation are presented.

  6. Comparison of Piezosurgery and Conventional Rotary Instruments for Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical and Radiographic Trial

    PubMed Central

    Shokry, Mohamed; Aboelsaad, Nayer

    2016-01-01

    The purpose of this study was to test the effect of the surgical removal of impacted mandibular third molars using piezosurgery versus the conventional surgical technique on postoperative sequelae and bone healing. Material and Methods. This study was carried out as a randomized controlled clinical trial: split mouth design. Twenty patients with bilateral mandibular third molar mesioangular impaction class II position B indicated for surgical extraction were treated randomly using either the piezosurgery or the conventional bur technique on each site. Duration of the procedure, postoperative edema, trismus, pain, healing, and bone density and quantity were evaluated up to 6 months postoperatively. Results. Test and control sites were compared using paired t-test. There was statistical significance in reduction of pain and swelling in test sites, where the time of the procedure was statistically increased in test site. For bone quantity and quality, statistical difference was found where test site showed better results. Conclusion. Piezosurgery technique improves quality of patient's life in form of decrease of postoperative pain, trismus, and swelling. Furthermore, it enhances bone quality within the extraction socket and bone quantity along the distal aspect of the mandibular second molar. PMID:27597866

  7. Comparison of Piezosurgery and Conventional Rotary Instruments for Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical and Radiographic Trial.

    PubMed

    Arakji, Hani; Shokry, Mohamed; Aboelsaad, Nayer

    2016-01-01

    The purpose of this study was to test the effect of the surgical removal of impacted mandibular third molars using piezosurgery versus the conventional surgical technique on postoperative sequelae and bone healing. Material and Methods. This study was carried out as a randomized controlled clinical trial: split mouth design. Twenty patients with bilateral mandibular third molar mesioangular impaction class II position B indicated for surgical extraction were treated randomly using either the piezosurgery or the conventional bur technique on each site. Duration of the procedure, postoperative edema, trismus, pain, healing, and bone density and quantity were evaluated up to 6 months postoperatively. Results. Test and control sites were compared using paired t-test. There was statistical significance in reduction of pain and swelling in test sites, where the time of the procedure was statistically increased in test site. For bone quantity and quality, statistical difference was found where test site showed better results. Conclusion. Piezosurgery technique improves quality of patient's life in form of decrease of postoperative pain, trismus, and swelling. Furthermore, it enhances bone quality within the extraction socket and bone quantity along the distal aspect of the mandibular second molar. PMID:27597866

  8. IOT Overview: IR Instruments

    NASA Astrophysics Data System (ADS)

    Mason, E.

    In this instrument review chapter the calibration plans of ESO IR instruments are presented and briefly reviewed focusing, in particular, on the case of ISAAC, which has been the first IR instrument at VLT and whose calibration plan served as prototype for the coming instruments.

  9. Astronomical Instruments in India

    NASA Astrophysics Data System (ADS)

    Sarma, Sreeramula Rajeswara

    The earliest astronomical instruments used in India were the gnomon and the water clock. In the early seventh century, Brahmagupta described ten types of instruments, which were adopted by all subsequent writers with minor modifications. Contact with Islamic astronomy in the second millennium AD led to a radical change. Sanskrit texts began to lay emphasis on the importance of observational instruments. Exclusive texts on instruments were composed. Islamic instruments like the astrolabe were adopted and some new types of instruments were developed. Production and use of these traditional instruments continued, along with the cultivation of traditional astronomy, up to the end of the nineteenth century.

  10. Mars Miniature Science Instruments

    NASA Technical Reports Server (NTRS)

    Kim, Soon Sam; Hayati, Samad; Lavery, David; McBrid, Karen

    2006-01-01

    For robotic Mars missions, all the science information is gathered through on-board miniature instruments that have been developed through many years of R&D. Compared to laboratory counterparts, the rover instruments require miniaturization, such as low mass (1-2 kg), low power (> 10 W) and compact (1-2 liter), yet with comparable sensitivity. Since early 1990's, NASA recognized the need for the miniature instruments and launched several instrument R&D programs, e.g., PIDDP (Planetary Instrument Definition and Development). However, until 1998, most of the instrument R&D programs supported only up to a breadboard level (TRL 3, 4) and there is a need to carry such instruments to flight qualifiable status (TU 5, 6) to respond to flight AOs (Announcement of Opportunity). Most of flight AOs have only limited time and financial resources, and can not afford such instrument development processes. To bridge the gap between instrument R&D programs and the flight instrument needs, NASA's Mars Technology Program (MTP) created advanced instrumentation program, Mars Instrument Development Project (MIDP). MIDP candidate instruments are selected through NASA Research Announcement (NRA) process [l]. For example, MIDP 161998-2000) selected and developed 10 instruments, MIDP II (2003-2005) 16 instruments, and MIDP III (2004-2006) II instruments.Working with PIs, JPL has been managing the MIDP tasks since September 1998. All the instruments being developed under MIDP have been selected through a highly competitive NRA process, and employ state-of-the-art technology. So far, four MIDP funded instruments have been selected by two Mars missions (these instruments have further been discussed in this paper).

  11. Afterword: Instruments as media, media as instruments.

    PubMed

    Rheinberger, Hans-Jörg

    2016-06-01

    The collection of essays comes under the heading of two catchwords: instruments and media. This Afterword looks at their interaction and roles in exploring the characteristics of living beings throughout history, especially their melding and gliding into each other. Before turning to the papers, I will make some more general remarks on instruments and media in scientific, and in particular, biological research. PMID:27053536

  12. Impact resistance of fiber composites: Energy absorbing mechanisms and environmental effects

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Sinclair, J. H.

    1983-01-01

    Energy absorbing mechanisms were identified by several approaches. The energy absorbing mechanisms considered are those in unidirectional composite beams subjected to impact. The approaches used include: mechanic models, statistical models, transient finite element analysis, and simple beam theory. Predicted results are correlated with experimental data from Charpy impact tests. The environmental effects on impact resistance are evaluated. Working definitions for energy absorbing and energy releasing mechanisms are proposed and a dynamic fracture progression is outlined. Possible generalizations to angle-plied laminates are described.

  13. Impact resistance of fiber composites - Energy-absorbing mechanisms and environmental effects

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Sinclair, J. H.

    1985-01-01

    Energy absorbing mechanisms were identified by several approaches. The energy absorbing mechanisms considered are those in unidirectional composite beams subjected to impact. The approaches used include: mechanic models, statistical models, transient finite element analysis, and simple beam theory. Predicted results are correlated with experimental data from Charpy impact tests. The environmental effects on impact resistance are evaluated. Working definitions for energy absorbing and energy releasing mechanisms are proposed and a dynamic fracture progression is outlined. Possible generalizations to angle-plied laminates are described.

  14. Piping inspection instrument carriage

    SciTech Connect

    Zollinger, W.T.; Treanor, R.C.

    1993-09-20

    This invention is comprised of a pipe inspection instrument carriage for use with a pipe crawler or other locomotion means for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has means mounted distally thereon for axially aligning the inspection instrumentation and means for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has means for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure.

  15. Regional Instrumentation Centers.

    ERIC Educational Resources Information Center

    Cromie, William J.

    1980-01-01

    Focuses on the activities of regional instrumentation centers that utilize the state-of-the-art instruments and methodology in basic scientific research. The emphasis is on the centers involved in mass spectroscopy, magnetic resonance spectroscopy, lasers, and accelerators. (SA)

  16. Woodwind Instrument Maintenance.

    ERIC Educational Resources Information Center

    Sperl, Gary

    1980-01-01

    The author presents a simple maintenance program for woodwind instruments which includes the care of tendon corks, the need for oiling keys, and methods of preventing cracks in woodwind instruments. (KC)

  17. Instrument Modeling and Synthesis

    NASA Astrophysics Data System (ADS)

    Horner, Andrew B.; Beauchamp, James W.

    During the 1970s and 1980s, before synthesizers based on direct sampling of musical sounds became popular, replicating musical instruments using frequency modulation (FM) or wavetable synthesis was one of the “holy grails” of music synthesis. Synthesizers such as the Yamaha DX7 allowed users great flexibility in mixing and matching sounds, but were notoriously difficult to coerce into producing sounds like those of a given instrument. Instrument design wizards practiced the mysteries of FM instrument design.

  18. Effect of specimen size and nickel content on the impact properties of 12 Cr-1 MoVW ferritic steel

    SciTech Connect

    Corwin, W.R.; Klueh, R.L.; Vitek, J.M.

    1983-01-01

    The ferritic steel 12 Cr-1 MoVW is a candidate material for use in the first wall of magnetic fusion reactors. One of the primary concerns of materials in this application is service-induced embrittlement from aging and irradiation. Unirradiated Charpy impact data have been developed on three typical heats of 12 Cr-1 MoVW steel and on heats that have been modified with nickel and chromium additions for subsequent simulation of helium effects of irradiation. The ductile-to-brittle transition temperature and the upper-shelf energy were reduced by nickel additions. The addition of nickel while simultaneously maintaining a constant net chromium equivalent caused the transition temperature to increase. The use of a subsize specimen is mandated by the small volume and high gamma heating in high-flux research reactors used for very high-fluence irradiation experiments. Therefore, an understanding of the behavior of the subsize specimen is important in predicting corresponding irradiation-induced transition temperature shifts and upper-shelf drops of full-size Charpy specimens. Data are reported from subsize Charpy impact specimens, and the full- and subsize specimens are compared. The effect of specimen size on the upper-shelf energy of this material can be reduced better by volume normalization than by area normalization.

  19. The Instrumental Model

    ERIC Educational Resources Information Center

    Yeates, Devin Rodney

    2011-01-01

    The goal of this dissertation is to enable better predictive models by engaging raw experimental data through the Instrumental Model. The Instrumental Model captures the protocols and procedures of experimental data analysis. The approach is formalized by encoding the Instrumental Model in an XML record. Decoupling the raw experimental data from…

  20. Instrumentation Working Group Summary

    NASA Technical Reports Server (NTRS)

    Zaller, Michelle; Miake-Lye, Richard

    1999-01-01

    The Instrumentation Working Group compiled a summary of measurement techniques applicable to gas turbine engine aerosol precursors and particulates. An assessment was made of the limits, accuracy, applicability, and technology readiness of the various techniques. Despite advances made in emissions characterization of aircraft engines, uncertainties still exist in the mechanisms by which aerosols and particulates are produced in the near-field engine exhaust. To adequately assess current understanding of the formation of sulfuric acid aerosols in the exhaust plumes of gas turbine engines, measurements are required to determine the degree and importance of sulfur oxidation in the turbine and at the engine exit. Ideally, concentrations of all sulfur species would be acquired, with emphasis on SO2 and SO3. Numerous options exist for extractive and non-extractive measurement of SO2 at the engine exit, most of which are well developed. SO2 measurements should be performed first to place an upper bound on the percentage of SO2 oxidation. If extractive and non-extractive techniques indicate that a large amount of the fuel sulfur is not detected as SO2, then efforts are needed to improve techniques for SO3 measurements. Additional work will be required to account for the fuel sulfur in the engine exhaust. Chemical Ionization Mass Spectrometry (CI-MS) measurements need to be pursued, although a careful assessment needs to be made of the sampling line impact on the extracted sample composition. Efforts should also be placed on implementing non-intrusive techniques and extending their capabilities by maximizing exhaust coverage for line-of-sight measurements, as well as development of 2-D techniques, where feasible. Recommendations were made to continue engine exit and combustor measurements of particulates. Particulate measurements should include particle size distribution, mass fraction, hydration properties, and volatile fraction. However, methods to ensure that unaltered

  1. Present status of aircraft instruments

    NASA Technical Reports Server (NTRS)

    1932-01-01

    This report gives a brief description of the present state of development and of the performance characteristics of instruments included in the following group: speed instruments, altitude instruments, navigation instruments, power-plant instruments, oxygen instruments, instruments for aerial photography, fog-flying instruments, general problems, summary of instrument and research problems. The items considered under performance include sensitivity, scale errors, effects of temperature and pressure, effects of acceleration and vibration, time lag, damping, leaks, elastic defects, and friction.

  2. Instrumenting Beliefs in Threshold Public Goods.

    PubMed

    de Oliveira, Angela C M; Spraggon, John M; Denny, Matthew J

    2016-01-01

    Understanding the causal impact of beliefs on contributions in Threshold Public Goods (TPGs) is particularly important since the social optimum can be supported as a Nash Equilibrium and best-response contributions are a function of beliefs. Unfortunately, investigations of the impact of beliefs on behavior are plagued with endogeneity concerns. We create a set of instruments by cleanly and exogenously manipulating beliefs without deception. Tests indicate that the instruments are valid and relevant. Perhaps surprisingly, we fail to find evidence that beliefs are endogenous in either the one-shot or repeated-decision settings. TPG allocations are determined by a base contribution and beliefs in a one shot-setting. In the repeated-decision environment, once we instrument for first-round allocations, we find that second-round allocations are driven equally by beliefs and history. Moreover, we find that failing to instrument prior decisions overstates their importance. PMID:26859492

  3. Instrumenting Beliefs in Threshold Public Goods

    PubMed Central

    2016-01-01

    Understanding the causal impact of beliefs on contributions in Threshold Public Goods (TPGs) is particularly important since the social optimum can be supported as a Nash Equilibrium and best-response contributions are a function of beliefs. Unfortunately, investigations of the impact of beliefs on behavior are plagued with endogeneity concerns. We create a set of instruments by cleanly and exogenously manipulating beliefs without deception. Tests indicate that the instruments are valid and relevant. Perhaps surprisingly, we fail to find evidence that beliefs are endogenous in either the one-shot or repeated-decision settings. TPG allocations are determined by a base contribution and beliefs in a one shot-setting. In the repeated-decision environment, once we instrument for first-round allocations, we find that second-round allocations are driven equally by beliefs and history. Moreover, we find that failing to instrument prior decisions overstates their importance. PMID:26859492

  4. Instrument to collect fogwater for chemical analysis

    SciTech Connect

    Jacob, D.J.; Waldman, J.M.; Haghi, M.; Hoffmann, M.R.; Flagan, R.C.

    1985-06-01

    An instrument is presented which collects large samples of ambient fogwater by impaction of droplets on a screen. The collection efficiency of the instrument is determined as a function of droplet size, and it is shown that fog droplets in the range 3--100-..mu..m diameter are efficiently collected. No significant evaporation or condensation occurs at any stage of the collection process. Field testing indicates that samples collected are representative of the ambient fogwater. The instrument may easily be automated, and is suitable for use in routine air quality monitoring programs.

  5. Review of Instrumented Indentation

    PubMed Central

    VanLandingham, Mark R.

    2003-01-01

    Instrumented indentation, also known as depth-sensing indentation or nanoindentation, is increasingly being used to probe the mechanical response of materials from metals and ceramics to polymeric and biological materials. The additional levels of control, sensitivity, and data acquisition offered by instrumented indentation systems have resulted in numerous advances in materials science, particularly regarding fundamental mechanisms of mechanical behavior at micrometer and even sub-micrometer length scales. Continued improvements of instrumented indentation testing towards absolute quantification of a wide range of material properties and behavior will require advances in instrument calibration, measurement protocols, and analysis tools and techniques. In this paper, an overview of instrumented indentation is given with regard to current instrument technology and analysis methods. Research efforts at the National Institute of Standards and Technology (NIST) aimed at improving the related measurement science are discussed.

  6. VIRUS instrument enclosures

    NASA Astrophysics Data System (ADS)

    Prochaska, T.; Allen, R.; Mondrik, N.; Rheault, J. P.; Sauseda, M.; Boster, E.; James, M.; Rodriguez-Patino, M.; Torres, G.; Ham, J.; Cook, E.; Baker, D.; DePoy, Darren L.; Marshall, Jennifer L.; Hill, G. J.; Perry, D.; Savage, R. D.; Good, J. M.; Vattiat, Brian L.

    2014-08-01

    The Visible Integral-Field Replicable Unit Spectrograph (VIRUS) instrument will be installed at the Hobby-Eberly Telescope† in the near future. The instrument will be housed in two enclosures that are mounted adjacent to the telescope, via the VIRUS Support Structure (VSS). We have designed the enclosures to support and protect the instrument, to enable servicing of the instrument, and to cool the instrument appropriately while not adversely affecting the dome environment. The system uses simple HVAC air handling techniques in conjunction with thermoelectric and standard glycol heat exchangers to provide efficient heat removal. The enclosures also provide power and data transfer to and from each VIRUS unit, liquid nitrogen cooling to the detectors, and environmental monitoring of the instrument and dome environments. In this paper, we describe the design and fabrication of the VIRUS enclosures and their subsystems.

  7. Wet chemistry instrument prototype

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A wet chemistry instrument prototype for detecting amino acids in planetary soil samples was developed. The importance of amino acids and their condensation products to the development of life forms is explained. The characteristics of the instrument and the tests which were conducted to determine the materials compatibility are described. Diagrams are provided to show the construction of the instrument. Data obtained from the performance tests are reported.

  8. Satellite oceanography - The instruments

    NASA Technical Reports Server (NTRS)

    Stewart, R. H.

    1981-01-01

    It is pointed out that no instrument is sensitive to only one oceanographic variable; rather, each responds to a combination of atmospheric and oceanic phenomena. This complicates data interpretation and usually requires that a number of observations, each sensitive to somewhat different phenomena, be combined to provide unambiguous information. The distinction between active and passive instruments is described. A block diagram illustrating the steps necessary to convert data from satellite instruments into oceanographic information is included, as is a diagram illustrating the operation of a radio-frequency radiometer. Attention is also given to the satellites that carry the various oceanographic instruments.

  9. Instrument validation project

    SciTech Connect

    Reynolds, B.A.; Daymo, E.A.; Geeting, J.G.H.; Zhang, J.

    1996-06-01

    Westinghouse Hanford Company Project W-211 is responsible for providing the system capabilities to remove radioactive waste from ten double-shell tanks used to store radioactive wastes on the Hanford Site in Richland, Washington. The project is also responsible for measuring tank waste slurry properties prior to injection into pipeline systems, including the Replacement of Cross-Site Transfer System. This report summarizes studies of the appropriateness of the instrumentation specified for use in Project W-211. The instruments were evaluated in a test loop with simulated slurries that covered the range of properties specified in the functional design criteria. The results of the study indicate that the compact nature of the baseline Project W-211 loop does not result in reduced instrumental accuracy resulting from poor flow profile development. Of the baseline instrumentation, the Micromotion densimeter, the Moore Industries thermocouple, the Fischer and Porter magnetic flow meter, and the Red Valve Pressure transducer meet the desired instrumental accuracy. An alternate magnetic flow meter (Yokagawa) gave nearly identical results as the baseline fischer and Porter. The Micromotion flow meter did not meet the desired instrument accuracy but could potentially be calibrated so that it would meet the criteria. The Nametre on-line viscometer did not meet the desired instrumental accuracy and is not recommended as a quantitative instrument although it does provide qualitative information. The recommended minimum set of instrumentation necessary to ensure the slurry meets the Project W-058 acceptance criteria is the Micromotion mass flow meter and delta pressure cells.

  10. Space applications instrumentation systems

    NASA Technical Reports Server (NTRS)

    Minzner, R. A.; Oberholtzer, J. D.

    1972-01-01

    A compendium of resumes of 158 instrument systems or experiments, of particular interest to space applications, is presented. Each resume exists in a standardized format, permitting entries for 26 administrative items and 39 scientific or engineering items. The resumes are organized into forty groups determined by the forty spacecraft with which the instruments are associated. The resumes are followed by six different cross indexes, each organized alphabetically according to one of the following catagories: instrument name, acronym, name of principal investigator, name of organization employing the principal investigator, assigned experiment number, and spacecraft name. The resumes are associated with a computerized instrument resume search and retrieval system.

  11. Impact Properties of Irradiated HT9 from the Fuel Duct of FFTF

    SciTech Connect

    Byun, Thak Sang; Maloy, S; Toloczko, M; Lewis, William Daniel

    2012-01-01

    This paper reports Charpy impact test data for the ACO-3 duct material (HT9) from the Fast Flux Test Facility (FFTF) and its archive material. Irradiation doses for the specimens were in the range of 3 148 dpa and irradiation temperatures in the range of 378 504 oC. The impact tests were performed for the small V-notched Charpy specimens with dimensions of 3 4 27 mm at an impact speed of 3.2 m/s in a 25J capacity machine. Irradiation lowered the upper-shelf energy (USE) and increased the transition temperatures significantly. The shift of transition temperatures was greater after relatively low temperature irradiation. The USE values were in the range of 5.5 6.7 J before irradiation and decreased to the range of 2 5 J after irradiation. Lower USEs were measured for lower irradiation temperatures and specimens with T-L orientation. For the irradiated specimens, the dose dependences of transition temperature and USE were not significant because of the radiation effect on impact behavior nearly saturated at the lowest dose of about 3 dpa. A comparison showed that the lateral expansion of specimens showed a linear correlation with absorbed impact energy, but with large scatter in the results. The size effect was also discussed to clarify the differences in the impact data of subsize and standard specimens.

  12. Interstellar Dust Instrumentation

    NASA Astrophysics Data System (ADS)

    Sternovsky, Zoltan; Gruen, E.; Horanyi, M.; Drake, K.; Collette, A.; Kempf, S.; Srama, R.; Postberg, F.; Krueger, H.; Auer, S.

    2010-10-01

    Interstellar grains traversing the inner planetary system have been identified by the Ulysses dust detector. Space dust detectors on other missions confirmed this finding. Analysis of the Stardust collectors is under way to search for and analyze such exotic grains. Interstellar dust particles can be detected and analyzed in the near-Earth space environment. New instrumentation has been developed to determine the origin of dust particles and their elemental composition. A Dust Telescope is a combination of a Dust Trajectory Sensor (DTS, Rev. Sci. Instrum. 79, 084501, 2008) together with a high mass resolution mass analyzer for the chemical composition of dust particles in space. Dust particles' trajectories are determined by the measurement of induced electric signals when a charged grain flies through a position sensitive electrode system. A modern DTS can measure dust particles as small as 0.2 micron in radius and dust speeds up to 100 km/s. Large area chemical analyzers of 0.1 m2 sensitive area have been tested at a dust accelerator and it was demonstrated that they have sufficient mass resolution to resolve ions with atomic mass number up to >100 (Earth, Moon and Planets, DOI: 10.1007/s11038-005-9040-z, 2005; Rev. Sci. Instrum. 78, 014501, 2007). The advanced Dust Telescope is capable of identifying interstellar and interplanetary grains, and measuring their mass, velocity vector, charge, elemental and isotopic compositions. An Active Dust Collector combines a DTS with an aerogel or other dust collector materials, e.g. like the ones used on the Stardust mission. The combination of a DTS with a dust collector provides not only individual trajectories of the collected particles but also their impact time and position on the collector which proves essential in finding collected sub-micron sized grains on the collector.

  13. Inclusion Practice Priorities Instrument.

    ERIC Educational Resources Information Center

    Montie, Jo; And Others

    This instrument was developed to assist individuals or teams to review best practice indicators regarding the development of inclusive school communities and to establish priority targets for improvement. The instrument covers three areas: (1) school community issues, (2) team issues, and (3) classroom issues. For each area, there is a review…

  14. Affective Involvement Instrument.

    ERIC Educational Resources Information Center

    Lemlech, Johanna K.

    1970-01-01

    The Affective Involvement Instrument (AII) describes and classifies affective involvement in the process of decision-making as it occurs during classroom activities such as role-playing or group discussions. The thirty-celled instrument behaviorizes the six processes involved in decision-making and combines them with the taxonomic levels of the…

  15. Developments in Electrochemical Instrumentation.

    ERIC Educational Resources Information Center

    Osteryoung, Janet

    1982-01-01

    Discusses developments in electrochemical instrumentation, including the role of computers, measurement/control instruments, present needs and future prospects. Indicates that microprocessors are used primarily for data processing, and that progress depends on noninstrumental factors such as electrode materials. (Author/JN)

  16. Thermally isolated well instruments

    SciTech Connect

    Engelder, P.D.

    1984-04-03

    A well instrument is isolated from the high temperatures of a surrounding earth formation by enclosing the instrument within a heat insulative jacket structure, preferably a dewar having spaced walls with a vacuum therebetween, with a heat sink contained in the jacket above the instrument assembly, and with a heat pipe extending upwardly from the instrument assembly to the heat sink and containing a fluid which by evaporation at a lower point and condensation at a higher point will conduct heat upwardly from the instrument assembly to the heat sink but not downwardly therebetween. The heat pipe preferably projects upwardly beyond a top portion of the insulating jacket to the location of a convector element which is exposed to the temperature of fluid or air at the outside of the insulating jacket to transmit heat from within the jacket to its exterior but not in a reverse direction.

  17. Aeronautic Instruments. Section II : Altitude Instruments

    NASA Technical Reports Server (NTRS)

    Mears, A H; Henrickson, H B; Brombacher, W G

    1923-01-01

    This report is Section two of a series of reports on aeronautic instruments (Technical Report nos. 125 to 132, inclusive). This section discusses briefly barometric altitude determinations, and describes in detail the principal types of altimeters and barographs used in aeronautics during the recent war. This is followed by a discussion of performance requirements for such instruments and an account of the methods of testing developed by the Bureau of Standards. The report concludes with a brief account of the results of recent investigations. For accurate measurements of altitude, reference must also be made to thermometer readings of atmospheric temperature, since the altitude is not fixed by atmospheric pressure alone. This matter is discussed in connection with barometric altitude determination.

  18. Subtask 12F4: Effects of neutron irradiation on the impact properties and fracture behavior of vanadium-base alloys

    SciTech Connect

    Chung, H.M.; Loomis, B.A.; Smith, D.L.

    1995-03-01

    Up-to-date results on the effects of neutron irradiation on the impact properties and fracture behavior of V, V-Ti, V-Cr-Ti and V-Ti-Si alloys are presented in this paper, with an emphasis on the behavior of the U.S. reference alloys V-4Cr-4Ti containing 500-1000 wppm Si. Database on impact energy and cluctile-brittle transition temperature (DBTT) has been established from Charpy impact tests of one-third-size specimens irradiated at 420{degrees}C-600{degrees}C up to {approx}50 dpa in lithium environment in fast fission reactors. To supplement the Charpy impact tests fracture behavior was also characterized by quantitative SEM fractography on miniature tensile and disk specimens that were irradiated to similar conditions and fractured at -196{degrees}C to 200{degrees}C by multiple bending. For similar irradiation conditions irradiation-induced increase in DBTT was influenced most significantly by Cr content, indicating that irradiation-induced clustering of Cr atoms takes place in high-Cr (Cr {ge} 7 wt.%) alloys. When combined contents of Cr and Ti were {le}10 wt.%, effects of neutron irradiation on impact properties and fracture behavior were negligible. For example, from the Charpy-impact and multiple-bend tests there was no indication of irradiation-induced embrittlement for V-5Ti, V-3Ti-1Si and the U.S. reference alloy V-4Cr-4Ti after irradiation to {approx}34 dpa at 420{degrees}C to 600{degrees}C, and only ductile fracture was observed for temperatures as low as -196{degrees}C. 14 refs., 8 figs., 1 tab.

  19. The DKIST Instrumentation Suite

    NASA Astrophysics Data System (ADS)

    Woeger, Friedrich

    2016-05-01

    The Daniel K. Inouye Solar Telescope with its four meter diameter aperture will be the largest telescope in the world for solar observations when it is commissioned in the year 2019. In order to harness its scientific potential immediately, DKIST will integrate five instruments that each will provide unique functionality to measure properties of the solar atmosphere at unprecedented spatial resolution.In this paper we discuss the unique capabilities in the DKIST instrument suite that consists of the Visible Broadband Imager (VBI), the Visible Spectro-Polarimeter (ViSP), the Visible Tunable Filter (VTF), the Diffraction-Limited Near-Infrared Spectro-Polarimeter (DL-NIRSP), and the Cryogenic Near-Infrared Spectro-Polarimeter (Cryo-NIRSP).In addition, we will explain the facility's approach to supporting high spatial resolution data acquisition with multiple instruments simultaneously by means of the Facility Instrument Distribution Optics. This system of wavelength separating and interchangeable beamsplitters will enable a variety of different ways to optically configure the light beam to the instruments. This approach ensures that the DKIST instruments can use their individual advantages in a multitude of different observing scenarios. The DKIST instrumentation suite will enable crucial new insights into complex physical processes that occur on spatial scales that are smaller than any solar structure observed in the past.

  20. Instrumentation Working Group Summary

    NASA Technical Reports Server (NTRS)

    Zaller, Michelle; Miake-Lye, Richard

    1999-01-01

    The Instrumentation Working Group compiled a summary of measurement techniques applicable to gas turbine engine aerosol precursors and particulates. An assessment was made of the limits, accuracy, applicability, and technology readiness of the various techniques. Despite advances made in emissions characterization of aircraft engines, uncertainties still exist in the mechanisms by which aerosols and particulates are produced in the near-field engine exhaust. To adequately assess current understanding of the formation of sulfuric acid aerosols in the exhaust plumes of gas turbine engines, measurements are required to determine the degree and importance of sulfur oxidation in the turbine and at the engine exit. Ideally, concentrations of all sulfur species would be acquired, with emphasis on SO2 and SO3. Numerous options exist for extractive and non-extractive measurement of SO2 at the engine exit, most of which are well developed. SO2 measurements should be performed first to place an upper bound on the percentage of SO2 oxidation. If extractive and non-extractive techniques indicate that a large amount of the fuel sulfur is not detected as SO2, then efforts are needed to improve techniques for SO3 measurements. Additional work will be required to account for the fuel sulfur in the engine exhaust. Chemical Ionization Mass Spectrometry (CI-MS) measurements need to be pursued, although a careful assessment needs to be made of the sampling line impact on the extracted sample composition. Efforts should also be placed on implementing non-intrusive techniques and extending their capabilities by maximizing exhaust coverage for line-of-sight measurements, as well as development of 2-D techniques, where feasible. Recommendations were made to continue engine exit and combustor measurements of particulates. Particulate measurements should include particle size distribution, mass fraction, hydration properties, and volatile fraction. However, methods to ensure that unaltered

  1. Instrument Attitude Precision Control

    NASA Technical Reports Server (NTRS)

    Juang, Jer-Nan

    2004-01-01

    A novel approach is presented in this paper to analyze attitude precision and control for an instrument gimbaled to a spacecraft subject to an internal disturbance caused by a moving component inside the instrument. Nonlinear differential equations of motion for some sample cases are derived and solved analytically to gain insight into the influence of the disturbance on the attitude pointing error. A simple control law is developed to eliminate the instrument pointing error caused by the internal disturbance. Several cases are presented to demonstrate and verify the concept presented in this paper.

  2. Aircraft Speed Instruments

    NASA Technical Reports Server (NTRS)

    Beij, K Hilding

    1933-01-01

    This report presents a concise survey of the measurement of air speed and ground speed on board aircraft. Special attention is paid to the pitot-static air-speed meter which is the standard in the United States for airplanes. Air-speed meters of the rotating vane type are also discussed in considerable detail on account of their value as flight test instruments and as service instruments for airships. Methods of ground-speed measurement are treated briefly, with reference to the more important instruments. A bibliography on air-speed measurement concludes the report.

  3. Mass spectrometers: instrumentation

    NASA Astrophysics Data System (ADS)

    Cooks, R. G.; Hoke, S. H., II; Morand, K. L.; Lammert, S. A.

    1992-09-01

    Developments in mass spectrometry instrumentation over the past three years are reviewed. The subject is characterized by an enormous diversity of designs, a high degree of competition between different laboratories working with either different or similar techniques and by extremely rapid progress in improving analytical performance. Instruments can be grouped into genealogical charts based on their physical and conceptual interrelationships. This is illustrated using mass analyzers of different types. The time course of development of particular instrumental concepts is illustrated in terms of the s-curves typical of cell growth. Examples are given of instruments which are at the exponential, linear and mature growth stages. The prime examples used are respectively: (i) hybrid instruments designed to study reactive collisions of ions with surfaces: (ii) the Paul ion trap; and (iii) the triple quadrupole mass spectrometer. In the area of ion/surface collisions, reactive collisions such as hydrogen radical abstraction from the surface by the impinging ion are studied. They are shown to depend upon the chemical nature of the surface through the use of experiments which utilize self-assembled monolayers as surfaces. The internal energy deposited during surface-induced dissociation upon collision with different surfaces in a BEEQ instrument is also discussed. Attention is also given to a second area of emerging instrumentation, namely technology which allows mass spectrometers to be used for on-line monitoring of fluid streams. A summary of recent improvements in the performance of the rapidly developing quadrupole ion trap instrument illustrates this stage of instrument development. Improvements in resolution and mass range and their application to the characterization of biomolecules are described. The interaction of theory with experiment is illustrated through the role of simulations of ion motion in the ion trap. It is emphasized that mature instruments play a

  4. Instrument intercomparisons and assessments

    NASA Astrophysics Data System (ADS)

    Albritton, D. L.; Zander, R. J.; Farmer, C. B.; Hilsenrath, E.; Mankin, W. G.; Murcray, D. G.; Pollitt, S.; Robbins, D. E.; Roscoe, H.

    Over the past few years, several field campaigns were devoted to the goal of assessing instrument reliability, as opposed to solely obtaining data to answer a geophysical question. Some examples of the formal instrument intercomparisons that have occurred in the past decade and those that are planned for the very near future are listed chronologically. Balloon-borne techniques and instruments that address the height profiles of the trace species in the lower stratosphere are emphasized. Beginning with the most extensively studied trace constituent, the approach taken and the results obtained, are described. The current status of the measurement capabilities are summarized, and the needs for future intercomparisons and assessments are listed.

  5. Writing Instrument Profiles for Mastery of Instrumental Analysis

    ERIC Educational Resources Information Center

    King, Daniel; Fernandez, Jorge; Nalliah, Ruth

    2012-01-01

    Because of the rapidly changing nature of chemical instrumentation, students must be trained in how to learn and understand new instruments. Toward this end, students are asked to create small instrument manuals, or instrument profiles, for the major pieces of equipment studied during an instrumental analysis course. This writing-intensive process…

  6. Tensile and Impact Toughness Properties of Gas Tungsten Arc Welded and Friction Stir Welded Interstitial Free Steel Joints

    NASA Astrophysics Data System (ADS)

    Lakshminarayanan, A. K.; Balasubramanian, V.

    2011-02-01

    Welded regions of interstitial free (IF) steel grades in the vicinity of weld center exhibits larger grains because of the prevailing thermal conditions during weld metal solidification. This often causes inferior weld mechanical properties. In the present study, tensile properties, charpy impact toughness, microhardness, microstructure, lowest hardness distribution profile, and fracture surface morphology of the gas tungsten arc welded (GTAW) and friction stir welded joints were evaluated, and the results are compared. From this investigation, it is found that friction stir welded joint of IF steel showed superior tensile and impact properties compared with GTAW joint, and this is mainly due to the formation of very fine, equiaxed microstructure in the weld zone.

  7. AIR Instrument Array

    NASA Technical Reports Server (NTRS)

    Jones, I. W.; Wilson, J. W.; Maiden, D. L.; Goldhagen, P.; Shinn, J. L.

    2003-01-01

    The large number of radiation types composing the atmospheric radiation requires a complicated combination of instrument types to fully characterize the environment. A completely satisfactory combination has not as yet been flown and would require a large capital outlay to develop. In that the funds of the current project were limited to essential integration costs, an international collaboration was formed with partners from six countries and fourteen different institutions with their own financial support for their participation. Instruments were chosen to cover sensitivity to all radiation types with enough differential sensitivity to separate individual components. Some instruments were chosen as important to specify the physical field component and other instruments were chosen on the basis that they could be useful in dosimetric evaluation. In the present paper we will discuss the final experimental flight package for the ER-2 flight campaign.

  8. CALIPSO Instrument Operational

    Atmospheric Science Data Center

    2014-09-18

    CALIPSO Instrument Operational Thursday, September 11, 2014 The CALIPSO payload is back in data acquisition mode as of Wednesday, September 17, 2014.  CALIPSO data processing has returned to a nominal state, and...

  9. Low cost instrumentation amplifier

    NASA Technical Reports Server (NTRS)

    Sturman, J. C.

    1974-01-01

    Amplifier can be used for many applications requiring high input impedance and common mode rejection, low drift, and gain accuracy on order of one percent. Performance of inexpensive amplifier approaches that of some commercial instrumentation amplifiers in many specifications.

  10. NPP: The Five Instruments

    NASA Video Gallery

    The NPP satellite has 5 instruments on board: VIIRS, CERES, CrIS, ATMS, and OMPS. Each one will deliver a specific set of data helping weather prediction and climate studies. This video is a quick ...

  11. Fiber Optics Instrumentation Development

    NASA Technical Reports Server (NTRS)

    Chan, Patrick Hon Man; Parker, Allen R., Jr.; Richards, W. Lance

    2010-01-01

    This is a general presentation of fiber optics instrumentation development work being conducted at NASA Dryden for the past 10 years and recent achievements in the field of fiber optics strain sensors.

  12. Cardiovascular instrumentation for spaceflight

    NASA Technical Reports Server (NTRS)

    Schappell, R. T.; Polhemus, J. T.; Ganiaris, N. J.

    1976-01-01

    The observation mechanisms dealing with pressure, flow, morphology, temperature, etc. are discussed. The approach taken in the performance of this study was to (1) review ground and space-flight data on cardiovascular function, including earlier related ground-based and space-flight animal studies, Mercury, Gemini, Apollo, Skylab, and recent bed-rest studies, (2) review cardiovascular measurement parameters required to assess individual performance and physiological alternations during space flight, (3) perform an instrumentation survey including a literature search as well as personal contact with the applicable investigators, (4) assess instrumentation applicability with respect to the established criteria, and (5) recommend future research and development activity. It is concluded that, for the most part, the required instrumentation technology is available but that mission-peculiar criteria will require modifications to adapt the applicable instrumentation to a space-flight configuration.

  13. Aeronautic Instruments. Section III : Aircraft Speed Instruments

    NASA Technical Reports Server (NTRS)

    Hunt, Franklin L; Stearns, H O

    1923-01-01

    Part 1 contains a discussion and description of the various types of air speed measuring instruments. The authors then give general specifications and performance requirements with the results of tests on air speed indicators at the Bureau of Standards. Part 2 reports methods and laboratory apparatus used at the Bureau of Standards to make static tests. Methods are also given of combining wind tunnel tests with static tests. Consideration is also given to free flight tests. Part 3 discusses the problem of finding suitable methods for the purpose of measuring the speed of aircraft relative to the ground.

  14. Instrumentation in Arthroscopy.

    PubMed

    Barp, Eric A; Erickson, John G; Reese, Eric R

    2016-10-01

    In recent years, arthroscopic procedures of the foot and ankle have seen a significant increase in both indications and popularity. Furthermore, technological advances in video quality, fluid management, and other arthroscopy-specific instruments continue to make arthroscopic procedures more effective with reproducible outcomes. As surgeons continue to use this approach, it is important that they have a complete understanding of the instrumentation available to them, including their indications and limitations. PMID:27599434

  15. Experimenting with woodwind instruments

    NASA Astrophysics Data System (ADS)

    Lo Presto, Michael C.

    2007-05-01

    Simple experiments involving musical instruments of the woodwind family can be used to demonstrate the basic physics of vibrating air columns in resonance tubes using nothing more than straightforward measurements and data collection hardware and software. More involved experimentation with the same equipment can provide insight into the effects of holes in the tubing and other factors that make simple tubes useful as musical instruments.

  16. Modeling of Musical Instruments

    NASA Astrophysics Data System (ADS)

    Bader, Rolf; Hansen, Uwe

    Signal processing techniques in acoustics address many concerns. Included are such things as wave propagation variables, amplitude considerations, spectral content, wavelength, and phase. Phase is primarily of concern when waves interact with each other, as well as with a medium, and the imposition of boundary conditions leads to normal mode vibrations. Such conditions are prevalent in all musical instruments, and thus relevant signal processing techniques are essential to both understanding and modeling the structure of musical instruments and the sound radiated.

  17. Advanced optical instruments technology

    NASA Technical Reports Server (NTRS)

    Shao, Mike; Chrisp, Michael; Cheng, Li-Jen; Eng, Sverre; Glavich, Thomas; Goad, Larry; Jones, Bill; Kaarat, Philip; Nein, Max; Robinson, William

    1992-01-01

    The science objectives for proposed NASA missions for the next decades push the state of the art in sensitivity and spatial resolution over a wide range of wavelengths, including the x-ray to the submillimeter. While some of the proposed missions are larger and more sensitive versions of familiar concepts, such as the next generation space telescope, others use concepts, common on the Earth, but new to space, such as optical interferometry, in order to provide spatial resolutions impossible with other concepts. However, despite their architecture, the performance of all of the proposed missions depends critically on the back-end instruments that process the collected energy to produce scientifically interesting outputs. The Advanced Optical Instruments Technology panel was chartered with defining technology development plans that would best improve optical instrument performance for future astrophysics missions. At this workshop the optical instrument was defined as the set of optical components that reimage the light from the telescope onto the detectors to provide information about the spatial, spectral, and polarization properties of the light. This definition was used to distinguish the optical instrument technology issues from those associated with the telescope, which were covered by a separate panel. The panel identified several areas for optical component technology development: diffraction gratings; tunable filters; interferometric beam combiners; optical materials; and fiber optics. The panel also determined that stray light suppression instruments, such as coronagraphs and nulling interferometers, were in need of general development to support future astrophysics needs.

  18. [The instrument for thermography].

    PubMed

    Hamaguchi, Shinsuke

    2014-07-01

    Thermography is an imaging method using the instrument to detect infrared rays emitted from the body surface, and to plot them as a distribution diagram of the temperature information. Therefore, a thermographic instrument can be assumed to measure the skin temperature of the diseased region. Such an instrument is a useful device for noninvasive and objective assessment of various diseases. Examination using a thermographic instrument can assess the autonomic dysfunction by measuring the skin blood flow involved with the sympathetic innervation. Thermography is useful in assisting the determination of the therapeutic effect. However, autonomic dysfunction should be confirmed correctly with the assessment of thermatome that shows abnormal thermal distribution in the region of the disease. Thermography should make noticeable the difference between the body temperature of abnormal and normal sites, and show the alteration of temperature. Monitoring using thermography is useful to determine the effect of sympathetic nerve block. If a thermographic instrument is used, it is important that examiners should understand the function of the instrument, as well as its advantages and disadvantages. PMID:25098130

  19. Aeronautic Instruments. Section V : Power Plant Instruments

    NASA Technical Reports Server (NTRS)

    Washburn, G E; Sylvander, R C; Mueller, E F; Wilhelm, R M; Eaton, H N; Warner, John A C

    1923-01-01

    Part 1 gives a general discussion of the uses, principles, construction, and operation of airplane tachometers. Detailed description of all available instruments, both foreign and domestic, are given. Part 2 describes methods of tests and effect of various conditions encountered in airplane flight such as change of temperature, vibration, tilting, and reduced air pressure. Part 3 describes the principal types of distance reading thermometers for aircraft engines, including an explanation of the physical principles involved in the functioning of the instruments and proper filling of the bulbs. Performance requirements and testing methods are given and a discussion of the source of error and results of tests. Part 4 gives methods of tests and calibration, also requirements of gauges of this type for the pressure measurement of the air pressure in gasoline tanks and the engine oil pressure on airplanes. Part 5 describes two types of gasoline gauges, the float type and the pressure type. Methods of testing and calibrating gasoline depth gauges are given. The Schroeder, R. A. E., and the Mark II flowmeters are described.

  20. The effect of heat treatment on the hardness and impact properties of medium carbon steel

    NASA Astrophysics Data System (ADS)

    Mazni Ismail, Noor; Khatif, Nurul Aida Amir; Aliff Kamil Awang Kecik, Mohamad; Hanafiah Shaharudin, Mohd Ali

    2016-02-01

    This paper covers the effect of heat treatment on the mechanical properties of medium carbon steel. The main objective of this project is to investigate the hardness and impact properties of medium carbon steel treated at different heat treatment processes. Three types of heat treatment were performed in this project which are annealing, quenching and tempering. During annealing process, the specimens were heated at 900°C and soaked for 1 hour in the furnace. The specimens were then quenched in a medium of water and open air, respectively. The treatment was followed by tempering processes which were done at 300°C, 450°C, and 600°C with a soaking time of 2 hours for each temperature. After the heat treatment process completed, Rockwell hardness test and Charpy impact test were performed. The results collected from the Rockwell hardness test and Charpy impact test on the samples after quenching and tempering were compared and analysed. The fractured surfaces of the samples were also been examined by using Scanning Electron Microscope. It was observed that different heat treatment processes gave different hardness value and impact property to the steel. The specimen with the highest hardness was found in samples quenched in water. Besides, the microstructure obtained after tempering provided a good combination of mechanical properties due to the process reduce brittleness by increasing ductility and toughness.

  1. The keyboard instruments.

    PubMed

    Manchester, Ralph A

    2014-06-01

    Now that the field of performing arts medicine has been in existence for over three decades, we are approaching a key point: we should start to see more articles that bring together the data that have been collected from several studies in order to draw more robust conclusions. Review articles and their more structured relative, the meta-analysis, can help to improve our understanding of a particular topic, comparing and synthesizing the results of previous research that has been done on that subject area. One way this could be done would be to review the research that has been carried out on the performance-related problems associated with playing a particular instrument or group of instruments. While I am not going to do that myself, I hope that others will. In this editorial, I will do a very selective review of the playing-related musculoskeletal disorders (PRMDs) associated with one instrument group (the keyboard instruments), focusing on the most played instrument in that group (the piano;). PMID:24925170

  2. Issues in Shuttle System Instrumentation

    NASA Technical Reports Server (NTRS)

    James, George

    2004-01-01

    The purose: a) Customer's perspective on Space Shuttle Return to Flight instrumentation; b) Focus on the difficult instrumentation issues; and c) Enable a discussion of new technologies (i.e.- NANO/MEMS/Small Tech) that could enhance Shuttle instrumentation posture. The T-10 Umbilical allows the vehicle instruments to be monitored and recorded prior to each launch and retract during launch.Launch Complex Instrumentation are instruments needed for assessment of Launch Commit Criteria (LCC) Salt-air and launch environments are issues. Instrumentation (Drag-On Instrumentation) can be added as needed to the vehicle for non-flight use. The current Roll-out Fatigue Testing is a primary example.

  3. Eigenvalues and musical instruments

    NASA Astrophysics Data System (ADS)

    Howle, V. E.; Trefethen, Lloyd N.

    2001-10-01

    Most musical instruments are built from physical systems that oscillate at certain natural frequencies. The frequencies are the imaginary parts of the eigenvalues of a linear operator, and the decay rates are the negatives of the real parts, so it ought to be possible to give an approximate idea of the sound of a musical instrument by a single plot of points in the complex plane. Nevertheless, the authors are unaware of any such picture that has ever appeared in print. This paper attempts to fill that gap by plotting eigenvalues for simple models of a guitar string, a flute, a clarinet, a kettledrum, and a musical bell. For the drum and the bell, simple idealized models have eigenvalues that are irrationally related, but as the actual instruments have evolved over the generations, the leading five or six eigenvalues have moved around the complex plane so that their relative positions are musically pleasing.

  4. Nonmetallic Diaphragms for Instruments

    NASA Technical Reports Server (NTRS)

    Eaton, H N; Buckingham, C T

    1925-01-01

    This report, the second of a series of reports relating to the general subject of instrument diaphragms. The first report of the series was published as Technical Report no. 165, "diaphragms for aeronautic instruments," and comprised an outline of historical developments and theoretical principles. The present report relates entirely to nonmetallic diaphragms, the use of which in certain types of pressure elements has been increasing for some time. Little, if any, information has been available to aid the designer of instruments using this form of pressure element. It was to attempt to meet the need for such information that the investigation reported in this paper was undertaken. The report describes the various materials which have been used as nonmetallic diaphragms, discusses the factors which affect the performance of the diaphragms and gives the results of tests made for the purpose of investigating the effect produced by these factors.

  5. Ozone Monitoring Instrument

    NASA Astrophysics Data System (ADS)

    de Vries, Johan

    The Ozone Monitoring Instrument is a trace gas monitoring instrument in the line of GOME (ERS-2) and Sciamachy (ENVISAT). Following these instruments, OMI provides UV-visible spectroscopy with a resolution sufficient to separate out the various absorbing trace gases (using DOAS or `Full' retrieval), but shaped as an imaging spectrometer. This means that a two dimensional detector is used where one dimension records the spectrum and the other images the swath. The scanning mechanism from the GOME and Sciamachy is not required anymore and there are considerable advantages with respect to simultaneous measurement of swath pixels, polarisation and obtainable swath width. The OMI consortium for a phase B is formed by Fokker Space & Systems and TPD in the Netherlands and VTT in Finland. In the presentation UV-visible atmospheric remote sensing will be placed in perspective and the OMI will be explaned.

  6. Virtual Sensor Test Instrumentation

    NASA Technical Reports Server (NTRS)

    Wang, Roy

    2011-01-01

    Virtual Sensor Test Instrumentation is based on the concept of smart sensor technology for testing with intelligence needed to perform sell-diagnosis of health, and to participate in a hierarchy of health determination at sensor, process, and system levels. A virtual sensor test instrumentation consists of five elements: (1) a common sensor interface, (2) microprocessor, (3) wireless interface, (4) signal conditioning and ADC/DAC (analog-to-digital conversion/ digital-to-analog conversion), and (5) onboard EEPROM (electrically erasable programmable read-only memory) for metadata storage and executable software to create powerful, scalable, reconfigurable, and reliable embedded and distributed test instruments. In order to maximize the efficient data conversion through the smart sensor node, plug-and-play functionality is required to interface with traditional sensors to enhance their identity and capabilities for data processing and communications. Virtual sensor test instrumentation can be accessible wirelessly via a Network Capable Application Processor (NCAP) or a Smart Transducer Interlace Module (STIM) that may be managed under real-time rule engines for mission-critical applications. The transducer senses the physical quantity being measured and converts it into an electrical signal. The signal is fed to an A/D converter, and is ready for use by the processor to execute functional transformation based on the sensor characteristics stored in a Transducer Electronic Data Sheet (TEDS). Virtual sensor test instrumentation is built upon an open-system architecture with standardized protocol modules/stacks to interface with industry standards and commonly used software. One major benefit for deploying the virtual sensor test instrumentation is the ability, through a plug-and-play common interface, to convert raw sensor data in either analog or digital form, to an IEEE 1451 standard-based smart sensor, which has instructions to program sensors for a wide variety of

  7. Inspector-instrument interface in portable NDA instrumentation

    SciTech Connect

    Halbig, J.K.; Klosterbuer, S.F.

    1981-01-01

    Recent electronics technology advances make it possible to design sophisticated instruments in small packages for convenient field implementation. This report describes an inspector-instrument interface design which allows communication of procedures, responses, and results between the instrument and user. The interface has been incorporated into new spent-fuel instrumentation and a battery-powered multichannel analyzer.

  8. Inspector-instrument interface in portable NDA instrumentation

    SciTech Connect

    Halbig, J.K.; Klosterbuer, S.F.

    1981-01-01

    Recent electronics technology advances make it possible to design sophisticated instruments in small packages for convenient field implementation. An inspector-instrument interface design that allows communication of procedures, responses, and results between the instrument and user is presented. This capability has been incorporated into new spent-fuel instrumentation and a battery-powered multichannel analyzer.

  9. [Hardening of dental instruments].

    PubMed

    Gerasev, G P

    1981-01-01

    The possibility of prolonging the service life of stomatological instruments by the local hardening of their working parts is discussed. Such hardening should be achieved by using hard and wear-resistant materials. The examples of hardening dental elevators and hard-alloy dental drills are given. New trends in the local hardening of instruments are the treatment of their working parts with laser beams, the application of coating on their surface by the gas-detonation method. The results of research work and trials are presented. PMID:7300627

  10. Advanced sensors and instrumentation

    NASA Technical Reports Server (NTRS)

    Calloway, Raymond S.; Zimmerman, Joe E.; Douglas, Kevin R.; Morrison, Rusty

    1990-01-01

    NASA is currently investigating the readiness of Advanced Sensors and Instrumentation to meet the requirements of new initiatives in space. The following technical objectives and technologies are briefly discussed: smart and nonintrusive sensors; onboard signal and data processing; high capacity and rate adaptive data acquisition systems; onboard computing; high capacity and rate onboard storage; efficient onboard data distribution; high capacity telemetry; ground and flight test support instrumentation; power distribution; and workstations, video/lighting. The requirements for high fidelity data (accuracy, frequency, quantity, spatial resolution) in hostile environments will continue to push the technology developers and users to extend the performance of their products and to develop new generations.