Application of the spectral analysis for the mathematical modelling

Document Sample
scope of work template
							Application of the spectral analysis
for the mathematical modelling of
      the rigid Earth rotation
                  V.V.Pashkevich

       Central (Pulkovo) Astronomical Observatory
             of Russian Academy of Science
                      St.Petersburg
   Space Research Centre of Polish Academy of Sciences
                        Warszawa

                          2004
  The aim of the investigation:
  Construction of a new high-precision series for the rigid Earth
  rotation, dynamically consistent with DE404/LE404 ephemeris
  and based on the SMART97 developments.

                      A L G O R I T H M:
1.   Numerical solutions of the rigid Earth rotation are constructed.
     Discrepancies of the comparison between our numerical
     solutions and the SMART97 ones are obtained in Euler angles.
2.   Investigation of the discrepancies was carried out by the least
     squares (LSQ) and by the spectral analysis (SA) methods. The
     secular and periodic terms were determined from the
     discrepancies.
3.   New precession and nutation series for the rigid Earth,
     dynamically consistent with DE404/LE404 ephemeris, were
     constructed.
                          Numerical            Discrepancies:
Initial conditions      integration of           Numerical
 from SMART97          the differential       Solutions minus
                          equations             SMART97

 Precession             LSQ method              6-th degree
  terms of            calculate secular      Polinomial of time
 SMART97                    terms

 Compute new           Remove the secular        SA method
  precession                 trend                calculate
  parameters           from discreapancies     periodical terms

              New precession
               and nutation          Construct a new
                  series              nutation series
 The calculations on Parsytec computer with a quadruple precision.
Fig.1. Difference between our numerical solution and SMART97
    a) in the longitude.
        Kinematical case                              Dynamical case




                        Secular terms of…                            Secular terms of…
       smart97 (as)             - d (as)         smart97(as)              - d (as)
                                     7.00                                           6.89
     50384564881.3693 T           - 206.50 T       50403763708.8052 T           - 206.90 T
                          2                    2                        2                    2
     - 107194853.5817 T          - 3451.30 T       - 107245239.9143 T          - 3180.80 T
                          3                    3                        3                    3
       - 1143646.1500 T           1125.00 T          - 1144400.2282 T            1048.00 T
                          4                    4                         4                   4
        1328317.7356 T            - 788.00 T           1329512.8261 T           - 306.00 T
                          5                    5                        5                    5
          - 9396.2895 T            - 57.50 T             - 9404.3004 T           - 65.50 T
                                               6                                             6
                                 - 3415.00 T                                   - 3421.00 T
Fig.1. Difference between our numerical solution and SMART97
    b) in the proper rotation.
         Kinematical case                                   Dynamical case




                        Secular terms of…                               Secular terms of…
       smart97 (as)               d(as)               smart97 (as)               d (as)
       1009658226149.3691             6.58                1009658226149.3691             6.53
  474660027824506304.0000 T        99598.30 T        474660027824506304.0000 T        97991.40 T
                               2                 2                                2                 2
          - 98437693.3264 T        - 7182.30 T                 98382922.2808 T        - 6934.40 T
                               3                 3                               3                  3
            - 1217008.3291 T        1066.80 T                  -1216206.2888 T         1004.00 T
                               4              4                                4                  4
             1409526.4062 T         - 750.00 T                  1408224.6897 T         - 226.00 T
                            5                 5                                  5                5
               - 9175.8967 T         - 30.30 T                    - 9168.0461 T         - 37.80 T
                                              6                                                   6
                                   - 3676.00 T                                        - 3682.00 T
Fig.1. Difference between our numerical solution and SMART97
    c) in the inclination.
        Kinematical case                             Dynamical case




                       Secular terms of…                            Secular terms of…
       smart97(as)              d(as)           smart97(as)               d(as)
     84381409000.0000               1.42          84381409000.0000                1.39
        - 265011.2586 T           - 96.61 T          - 265001.7085 T           - 96.73 T
                          2                 2                          2                   2
         5127634.2488 T          - 353.10 T          5129588.3567 T           - 595.90 T
                          3                   3                        3                   3
       - 7727159.4229 T           771.50 T          - 7731881.2221 T          - 945.10 T
                          4                   4                        4                   4
          - 4916.7335 T           - 84.50 T            - 4930.2027 T            - 76.50 T
                        5                     5                        5                   5
           33292.5474 T           - 86.00 T            33330.6301 T             - 70.00 T
                                              6                                            6
                                 - 247.50 T                                   - 247.80 T
Fig.2. Difference between our numerical solution and SMART97
      after formal removal of secular trends.
        Kinematical case                Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle.
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle.
       Kinematical case                 Dynamical case




           3


   1   2
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1
      Kinematical case                  Dynamical case


                B




  A
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 A
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 A
       Kinematical case                 Dynamical case


                   II




   I
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 A-I
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 A-II
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 A-II
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 A-II (zoom)
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 B
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 B
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 B (zoom)
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 B (zoom)
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 1 B (zoom2)
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 2
      Kinematical case                  Dynamical case
Fig.3. Spectra of discrepancies between our numerical solution and
       SMART97 for proper rotation angle. DETAIL 3
      Kinematical case                  Dynamical case
Fig.4. Difference between our numerical solution and SMART97 after
formal removal the secular trends and 9000 periodical harmonics.
          Kinematical case                 Dynamical case
Fig.5. Repeated Numerical Solution minus New Series.

          Kinematical case                 Dynamical case
Fig.6. Numerical solution minus New Series after formal removal
       secular trends in the proper rotation angle.
           Kinematical case                  Dynamical case
Fig.6. Numerical solution minus New Series after formal removal
       secular trends in the proper rotation angle. (zoom)
           Kinematical case                  Dynamical case
           The calculations on PC with a double precision.
Fig.7. Numerical solution minus New Series after formal removal
       secular trends in the proper rotation angle.

           Kinematical case                  Dynamical case
Fig.8. Sub diurnal and diurnal spectra of discrepancies between our
numerical solution and SMART97 for proper rotation angle.
      Kinematical case                  Dynamical case
Fig.9. Numerical solution minus New Series including sub diurnal and
diurnal periodical terms after formal removal secular trends in the proper
rotation angle.
            Kinematical case                     Dynamical case
                          CONCLUSION

• Spectral analysis of discrepancies of the numerical solutions and
  SMART97 solutions of the rigid Earth rotation was carried out for the
  kinematical and dynamical cases over the time interval of 2000 years.
• Construction of a new series of the rigid Earth rotation, dynamically
  consistent with DE404/LE404 ephemeris, were performed for
  dynamical and kinematical cases.
• The power spectra of the residuals for the dynamical and kinematical
  cases are similar.
• The secular trend in proper rotation found in the difference between
  the numerical solutions and new series is considerably smaller than
  that found in the difference between the numerical solutions and
  SMART97.
                ACKNOWLEDGMENTS

The investigation was carried out at the
Central (Pulkovo) Astronomical Observatory of Russian Academy of Science
and the
Space Research Centre of Polish Academy of Science,
under a financial support of the
Cooperation between Polish and Russian Academies of Sciences,
Theme No 25 and of the
Russian Foundation for Fundamental Research,
 Grant No 02-02-17611.
    http://www.csa.ru/




                  Center for supercomputing applications
       The massive-parallel computer system Parsytec CCe20
                                               •   Parsytec CCe20 is a supercomputer of
                                                   massive-parallel architecture with separated
                                                   memory. It is intended for fulfilment of
                                                   high-performance parallel calculations.

                                             Hardware:
                                             • 20 computing nodes with processors PowerPC
                                                604e (300MHz);
                                             • 2 nodes of input-output;
Massive-parallel supercomputers Parsytec is
designed by Parsytec GmbH, Germany,          • The main memory:
using Cognitive Computer technology.              o 32 Mb on computing nodes;
                                                  o 64 Mb on nodes of an input / conclusion;
The system approach is based on using of     • disk space 27 Gb;
PC technology and RISC processors
                                             • tape controller DAT;
PowerPC which are ones of the most
powerful processor platforms available today • CD-ROM device;
and are clearly outstanding in price /       • network interface Ethernet (10/100 Mbs);
performance.                                 • communication interface HighSpeed Link (HS-
                                                Link)
There are 5 Parsytec computers in CSA now .
SA method for cleaning the discrepancies calculated periodical terms

  Discrepancies after removal            Set of nutation terms of
                                         SMART97
  the secular trend

                  LSQ method compute amplitude
                  of power spectrum of discrepancies

   LSQ method determine amplitudes
   and phases of the largest rest harmonic       Nutation terms
                                                 of SMART97
       if |Am| > ||      Compute a new
                          nutation term                 Construct
  No               Yes
                                                        a new
    Until the end        Remove this harmonic from      nutation
    of specta            discrepancy and Spectra        series
Quadruple precision corresponding to 32- decimal
representation of real numbers.

Double precision corresponding to 16- decimal representation
of real numbers.
Fig.5 Repeated Numerical Solution minus New Series.

   Kinematical case                 Dynamical case