Sample records for aasta parim multifilm

  1. Spectral analysis of the UFBG-based acousto—optical modulator in V-I transmission matrix formalism

    NASA Astrophysics Data System (ADS)

    Wu, Liang-Ying; Pei, Li; Liu, Chao; Wang, Yi-Qun; Weng, Si-Jun; Wang, Jian-Shuai

    2014-11-01

    In this study, the V-I transmission matrix formalism (V-I method) is proposed to analyze the spectrum characteristics of the uniform fiber Bragg grating (FBG)-based acousto—optic modulators (UFBG-AOM). The simulation results demonstrate that both the amplitude of the acoustically induced strain and the frequency of the acoustic wave (AW) have an effect on the spectrum. Additionally, the wavelength spacing between the primary reflectivity peak and the secondary reflectivity peak is proportional to the acoustic frequency with the ratio 0.1425 nm/MHz. Meanwhile, we compare the amount of calculation. For the FBG whose period is M, the calculation of the V-I method is 4 × (2M-1) in addition/subtraction, 8 × (2M - 1) in multiply/division and 2M in exponent arithmetic, which is almost a quarter of the multi-film method and transfer matrix (TM) method. The detailed analysis indicates that, compared with the conventional multi-film method and transfer matrix (TM) method, the V-I method is faster and less complex.

  2. Longitudinal variation of the equatorial ionosphere: Modeling and experimental results

    NASA Astrophysics Data System (ADS)

    Souza, J. R.; Asevedo, W. D.; dos Santos, P. C. P.; Petry, A.; Bailey, G. J.; Batista, I. S.; Abdu, M. A.

    2013-02-01

    We describe a new version of the Parameterized Regional Ionospheric Model (PARIM) which has been modified to include the longitudinal dependences. This model has been reconstructed using multidimensional Fourier series. To validate PARIM results, the South America maps of critical frequencies for the E (foE) and F (foF2) regions were compared with the values calculated by Sheffield Plasmasphere-Ionosphere Model (SUPIM) and IRI representations. PARIM presents very good results, the general characteristics of both regions, mainly the presence of the equatorial ionization anomaly, were well reproduced for equinoctial conditions of solar minimum and maximum. The values of foF2 and hmF2 recorded over Jicamarca (12°S; 77°W; dip lat. 1°N; mag. declination 0.3°) and sites of the conjugate point equatorial experiment (COPEX) campaign Boa Vista (2.8°N; 60.7°W; dip lat. 11.4°; mag. declination -13.1°), Cachimbo (9.5°S; 54.8°W; dip lat. -1.8°; mag. declination -15.5°), and Campo Grande (20.4°S; 54.6°W; dip lat. -11.1°; mag. declination -14.0°) have been used in this work. foF2 calculated by PARIM show good agreement with the observations, except during morning over Boa Vista and midnight-morning over Campo Grande. Some discrepancies were also found for the F-region peak height (hmF2) near the geomagnetic equator during times of F3 layer occurrences. IRI has underestimated both foF2 and hmF2 over equatorial and low latitude sectors during evening-nighttimes, except for Jicamarca where foF2 values were overestimated.

  3. NASA Public Affairs and NUANCE Lab News Conference at Reno-Stead Airport.

    NASA Image and Video Library

    2016-10-19

    News Conference following the test of Unmanned Aircraft Systems Traffic Management (UTM) technical capability Level 2 (TCL2) at Reno-Stead Airport, Nevada. Parimal Kopardekar, NASA Ames Senior Engineer for Ait Transportation Systems gave an overview of UTM.

  4. NASA Public Affairs and NUANCE Lab News Conference at Reno-Stead Airport.

    NASA Image and Video Library

    2016-10-19

    News Conference following the test of Unmanned Aircraft Systems Traffic Management (UTM) technical capability Level 2 (TCL2) at Reno-Stead Airport, Nevada. Parimal Kopardekar, NASA Ames Senior Engineer for Ait Transportation Systems gave an overview of UTM (Left).

  5. NASA Public Affairs and NUANCE Lab News Conference at Reno-Stead Airport.

    NASA Image and Video Library

    2016-10-19

    News Conference following the test of Unmanned Aircraft Systems Traffic Management (UTM) technical capability Level 2 (TCL2) at Reno-Stead Airport, Nevada. Parimal Kopardekar, NASA Ames Senior Engineer for Ait Transportation Systems gave an overview of UTM (Left). Huy Tran, NASA Ames Aeronautics Director, presents NASA UTM Project Overview.

  6. NASA Public Affairs and NUANCE Lab News Conference at Reno-Stead Airport.

    NASA Image and Video Library

    2016-10-19

    News Conference following the test of Unmanned Aircraft Systems Traffic Management (UTM) technical capability Level 2 (TCL2) at Reno-Stead Airport, Nevada. Parimal Kopardekar, NASA Ames Senior Engineer for Ait Transportation Systems gave an overview of UTM (Left). Tom Wilczek, Aerospace and Defence industry representative and Nevada Govenor's Office of Economic Development (Right).

  7. NASA Public Affairs and NUANCE Lab News Conference at Reno-Stead Airport.

    NASA Image and Video Library

    2016-10-19

    News Conference following the test of Unmanned Aircraft Systems Traffic Management (UTM) technical capability Level 2 (TCL2) at Reno-Stead Airport, Nevada. Parimal Kopardekar, NASA Ames Senior Engineer for Ait Transportation Systems gave an overview of UTM (Left). Maril Mora (Podium), President / CEO of the Reno -Tahoe Airport Authority welcomes NASA and Partners.

  8. Method of Preparation AZP4330 PR Pattern with Edge Slope 40°

    NASA Astrophysics Data System (ADS)

    Wu, Jie; Zhao, Hongyuan; Yu, Yuanwei; Zhu, Jian

    2018-03-01

    When the edge which is under the multi-film is more steep or angular, the stress in the multilayer film near the edge is concentrated, this situation will greatly reduce the reliability of electronic components. And sometimes, we need some special structure such as a slope with a specific angle in the MEMS, so that the metal line can take the signal to the output pad through the slope instead of deep step. To cover these problems, the lithography method of preparing the structure with edge slope is studied. In this paper, based on the Kirchhoff scalar diffraction theory we try to change the contact exposure gap and the post-baking time at the specific temperature to find out the effect about the edge angle of the photoresist. After test by SEM, the results were presented by using AZP4330 photoresist, we can get the PR Pattern with edge slope 40° of the process and the specific process parameters.

  9. NASA Public Affairs and NUANCE Lab News Conference at Reno-Stead Airport.

    NASA Image and Video Library

    2016-10-19

    News Conference following the test of Unmanned Aircraft Systems Traffic Management (UTM) technical capability Level 2 (TCL2) at Reno-Stead Airport, Nevada. The UTM Reno Press Conference on Oct. 19, 2016. (Left to Right) Parimal Kopardekar, NASA Ames Senior Engineer for Air Transportation Systems gave an overview of UTM; Maril Mora, President / CEO of the Reno -Tahoe Airport Authority welcomes NASA and Partners; Tom Wilczek, Aerospace and Defence industry representative and Nevada Governor's Office of Economic Development; Mark Baker, Director of Business Development, Nevada Institute of Autonomous Systems; Manos Maragakis, Dean of the College of Engineering, University of Nevada, Reno.

  10. Penetration of multiple thin films in micrometeorite capture cells

    NASA Technical Reports Server (NTRS)

    Simon, Charles G.

    1994-01-01

    As part of a continuing effort to develop cosmic dust detectors/collectors for use in space, we performed a series of hypervelocity impact experiments on combined sensor/capture-cell assemblies using 10-200-micron-diameter glass projectiles and olivine crystals at velocities of 0.9-14.4 km/s. The design objective of the space-flight instrument is to measure the trajectories of individual particles with sufficient accuracy to permit identification of their parent bodies and to capture enough impactor material to allow chemical and isotopic analyses of samples returned to Earth. Three different multiple-film small-particle capture cell designs (0.1-100-micron-thick Al foils with approx. 10, 100, and 1800 micron spacing) were evaluated for their ability to capture impactor fragments and residue. Their performances were compared to two other types of capture cells, foil covered Ge crystals, and 0.50 and 0.120 g/cu cm aerogels. All capture cells were tested behind multifilm (1.4-6.0-micron-thick) polyvinylidene fluoride (PVDF) velocity/trajectory sensor devices. Several tests were also done without the PVDF sensors for comparison. The results of this study were reported by Simon in a comprehensive report in which the morphology of impacts and impactor residues in various types of capture cells after passage through two PVDF sensor films is discussed. Impactor fragments in selected capture cells from impacts at velocities up to 6.4 km/s were identified using scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS).