ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Electronic Resource

The Iceland 1986 GPS geodetic survey: tectonic goals and data processing results (1993)

Foulger, G. R. ; Beutler, G. ; Bilham, Roger ; [et al.]

Springer

Journal of geodesy 67 (1993), S. 148-172

add to mindlist on the mindlist

Details

ISSN: 1432-1394

Source: Springer Online Journal Archives 1860-2000

Topics: Architecture, Civil Engineering, Surveying

Notes: Summary The 1986 GPS survey of Iceland aimed to: (1) establish geodetic control in the South Iceland Seismic Zone (SISZ), to study destructive earthquakes there, (2) measure a country-wide network to form the basis of a new first order national network. 51 points were surveyed, with 20–30 km spacings within the SISZ and 100 km spacings elsewhere. The data were processed using the Bernese GPS software Version 3. Analysis was difficult due to poor satellite geometry and short-period ionospheric variations. However, an ambiguity-fixed, ionosphere-free solution gave accuracies of 1–2 cm in the horizontal and 2–3 cm in the vertical for the SISZ network and an ambiguity-free, ionosphere-free solution yielded accuracies of about 5 cm for the country-wide network. An ionosphere-free solution for the total survey with ambiguities fixed for the SISZ network only gave marginal additional improvements over the two separate solutions. GPS surveying has continued annually in Iceland with measurements in South Iceland in 1989 and 1992 (Hackman 1991; Sigmundsson 1992) and in North Iceland in 1987, 1990 and 1992 (Jahn et al. 1992; Foulger et al. 1992).

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00806254

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

2

Electronic Resource

Combining consecutive short arcs into long arcs for precise and efficient GPS Orbit Determination (1996)

Beutler, G. ; Brockmann, E. ; Hugentobler, U. ; [et al.]

Springer

Journal of geodesy 70 (1996), S. 287-299

add to mindlist on the mindlist

Details

ISSN: 1432-1394

Source: Springer Online Journal Archives 1860-2000

Topics: Architecture, Civil Engineering, Surveying

Notes: Abstract. The final products of the CODE Analysis Center (Center for Orbit Determination in Europe) of the International GPS Service for Geodynamics (IGS) stem from overlapping 3-days-arcs. Until 31 December, 1994 these long arcs were computed from scratch, i.e. by processing three days of observations of about 40 stations (by mid 1995 about 60 stations were used) of the IGS Global Network in our parameter estimation program GPSEST. Because one-day-arcs have to be produced first (for the purpose of error detection etc.) the actual procedure was rather time-consuming. In the present article we develop the mathematical tools necessary to form arcs based on the normal equation systems of consecutive short arcs (one-day-solutions in the case of CODE). The procedure in its simplest version is as follows: • Each short arc is described by six initial conditions and a number of dynamical orbit parameters (e.g. radiation pressure parameters). The resulting long arc in turn shall be based on n consecutive short arcs and described by six initial conditions and again the same number of dynamical parameters as in the short arcs. • By asking position and velocity to be continuous at the boundaries of the short arcs we obtain a long arc which is actually defined by one set of initial conditions and n sets of dynamical parameters (if n short arcs are combined). • By asking the dynamical parameters to be identical in consecutive short arcs, the resulting long arc is characterized by exactly the same number of orbit parameters as each of the short arcs. • This procedure is not yet optimized because formally all n sets of orbit parameters have to be set up and solved for in the long arc solution (although they are not independent). In order to allow for an optimized solution we derive all necessary relations to eliminate the unnecessary parameters in the combination. Each long arc is characterized by the actual number of independent orbit parameters. The resulting procedure is very efficient. From the point of view of the result the new procedure is completely equivalent to an actual re-evaluation of all observations pertaining to the long arc. It is much more efficient and flexible, however because it allows us to construct 2-day-arcs, 3-day-arcs, etc. based on the previously stored daily normal equation systems without requiring much additional CPU time. The theory is developed in the first four sections. Technical aspects are dealt with in appendices A and B. The actual implementation into the Bernese GPS Software system and test results are given in section 5.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00867349

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

3

Electronic Resource

Improving the orbit estimates of GPS satellites (1999)

Springer, T. A. ; Beutler, G. ; Rothacher, M.

Springer

Journal of geodesy 73 (1999), S. 147-157

add to mindlist on the mindlist

Details

ISSN: 1432-1394

Keywords: Key words. GPS ; Solar radiation pressure ; Orbit estimation

Source: Springer Online Journal Archives 1860-2000

Topics: Architecture, Civil Engineering, Surveying

Notes: Abstract. The Extended Center for Orbit Determination in Europe (CODE) Orbit Model, an empirical orbit model proposed by Beutler and colleagues in 1994, has been tested extensively since January 1996. Apart from six osculating Keplerian elements, this orbit model consists of nine (instead of the conventional two) parameters to take into account the deterministic part of the force field acting on the satellites. Based on the test results an improved orbit parameterization is proposed. The new orbit parameterization consists of the conventional two parameters plus three additional parameters, a constant and two periodic terms (a cosine and a sine term), in the X-direction to model the effects of the solar radiation pressure. Results based on one full year of routine orbit estimation, using the original and the new orbit parameterization, are presented to demonstrate the superiority of the new approach. An improvement of the orbit estimates with at least a factor of two is observed!

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/s001900050230

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

4

Electronic Resource

Analysis of the first year of Earth rotation parameters with a sub-daily resolution gained at the CODE processing center of the IGS (2000)

Hefty, J. ; Rothacher, M. ; Springer, T. ; [et al.]

Springer

Journal of geodesy 74 (2000), S. 479-487

add to mindlist on the mindlist

Details

ISSN: 1432-1394

Keywords: Key words: Sub-daily Earth rotation parameters – GPS permanent network processing – Ocean tides

Source: Springer Online Journal Archives 1860-2000

Topics: Architecture, Civil Engineering, Surveying

Notes: Abstract. The solutions of the CODE Analysis Center submitted to the IGS, the International Global Position System (GPS) Service for Geodynamics, are based on three days of observation of about 80–100 stations of the IGS network. The Earth rotation parameters (ERPs) are assumed to vary linearly over the three days with respect to an a priori model. Continuity at the day boundaries as well as the continuity of the first derivatives are enforced by constraints. Since early April 1995 CODE has calculated a new ERP series with an increased time resolution of 2 hours. Again continuity is enforced at the 2-hours-interval boundaries. The analysis method is described, particularly how to deal with retrograde diurnal terms in the ERP series which may not be estimated with satellite geodetic methods. The results obtained from the first year of data covered by the time series (time interval from 4 April 1995 to 30 June 1996) are also discussed. The series is relatively homogeneous in the sense of the used orbit model and the a priori model for the ERPs. The largest source of excitation at daily and sub-daily periods is likely to be the effect of the ocean tides. There is good agreement between the present results and Topex/Poseidon ocean tide models, as well as with models based on Very Long Baseline Interferometry (VLBI) and Satellite Laser Ranging (SLR) data. Non-oceanic periodic variations are also observed in the series. Their origin is most probably a consequence of the GPS solution strategy; other possible sources are the atmospheric tides.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/s001900000108

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

5

Electronic Resource

Combining consecutive short arcs into long arcs for precise and efficient GPS Orbit Determination (1996)

Beutler, G. ; Brockmann, E. ; Hugentobler, U. ; [et al.]

Springer

Journal of geodesy 70 (1996), S. 287-299

add to mindlist on the mindlist

Details

ISSN: 1432-1394

Source: Springer Online Journal Archives 1860-2000

Topics: Architecture, Civil Engineering, Surveying

Notes: Abstract The final products of theCODE Analysis Center (Center for Orbit Determination in Europe) of theInternational GPS Service for Geodynamics (IGS) stem fromoverlapping 3-day-arcs. Until 31 December, 1994 these long arcs were computedfrom scratch, i.e. by processing three days of observations of about 40 stations (by mid 1995 about 60 stations were used) of the IGS Global Network in our parameter estimation program GPSEST. Becauseone-day-arcs have to be produced first (for the purpose of error detection etc.) the actual procedure was rather time-consuming. In the present article we develop the mathematical tools necessary to form long arcs based on the normal equation systems of consecutive short arcs (one-day-solutions in the case of CODE). The procedure in its simplest version is as follows: Each short arc is described bysix initial conditions and a number of dynamical orbit parameters (e.g. radiation pressure parameters). The resulting long arc in turn shall be based onn consecutive short arcs and described bysix initial conditions and again the same number of dynamical parameters as in the short arcs.. By asking position and velocity to be continuous at the boundaries of the short arcs we obtain a long arc which is actually defined by one set of initial conditions andn sets of dynamical parameters (ifn short arcs are combined).. By asking the dynamical parameters to be identical in consecutive short arcs, the resulting long arc is characterized by exactly the same number of orbit parameters as each of the short arcs. This procedure isnot yet optimized becauseformally all n sets of orbit parameters have to be set up and solved for in the long arc solution (although they are not independent). In order to allow for an optimized solution we derive all necessary relations to eliminate the unnecessary parameters in the combination. Each long arc is characterized by the actual number of independent orbit parameters. The resulting procedure isvery efficient. From the point of view of the result the new procedure iscompletely equivalent to an actual re-evaluation of all observations pertaining to the long arc. It is much more efficient and flexible, however because it allows us to construct 2-day-arcs, 3-day-arcs, etc. based on the previously stored daily normal equation systems without requiring much additional CPU time. The theory is developed in the first four sections. Technical aspects are dealt with in appendices A and B. The actual implementation into the Bernese GPS Software system and test results are given in section 5.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00867349

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

6

Electronic Resource

A New Solar Radiation Pressure Model for GPS Satellites (1999)

Springer, T. A. ; Beutler, G. ; Rothacher, M.

Springer

GPS solutions 2 (1999), S. 50-62

add to mindlist on the mindlist

Details

ISSN: 1521-1886

Source: Springer Online Journal Archives 1860-2000

Topics: Architecture, Civil Engineering, Surveying , Geosciences

Notes: The largest error in currently used GPS orbit models is due to the effect of solar radiation pressure. Over the last few years many improvements were made in modeling the orbits of GPS satellites within the International GPS Service (IGS). Howeer, most improvements were achieved by increasing the number of estimated orbit and/or solar radiation pressure parameters. This increase in the number of estimated satellite parameters weakens the solutions of all estimated parameters (not only orbit parameters). Because of correlations the additional orbit parameters may introduce biases in other estimated quantities, for example the length of day. We present a recently developed solar radiation pressure model for the GPS satellites. This model is based on experiences and results gained at the Center for Orbit Determination in Europe (CODE) in the context of its IGS activities since June 1992. The performance of the new model is almost an order of magnitude better than that of the existing ROCK models. It also allows a reduction of the number of orbit parameters that have to be estimated. © 1999 John Wiley & Sons, Inc.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/PL00012757

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

7

Unknown

Biomimetics with a Self-Assembled Monolayer of Catalytically Active Tethered Isoalloxazine on Au (2005)

Calvo, Ernesto J. ; Rothacher, M. Silvina ; Bonazzola, Cecilia ; [et al.]

American Chemical Society

In: Langmuir. 2005; 21(17): 7907-7911. Published 2005 Aug 01. doi: 10.1021/la050695n.

add to mindlist on the mindlist

Details

Publication Date: 2005-08-01

Print ISSN: 0743-7463

Electronic ISSN: 1520-5827

Topics: Chemistry and Pharmacology

Published by American Chemical Society

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

PAPER CURRENT

S·F·X

Fulltext

8

Unknown

Long-period surface motion of the multipatch Mw9.0 Tohoku-Oki earthquake (2014)

Psimoulis, P. A., Houlie, N., Michel, C., Meindl, M., Rothacher, M.

Oxford University Press

In: Geophysical Journal International

add to mindlist on the mindlist

Details

Publication Date: 2014-09-11

Description: We show that it is possible to capture the oscillatory ground motion induced by the Tohoku-Oki event for periods ranging from 3 to 100 s using precise point positioning. We find that the ground motions of the sedimentary basins of Japan were large (respectively 〉0.15 m s –1 and 〉0.15 m s –2 for velocity and acceleration) even for periods larger than 3 s. We compare geodetic observables with a ground motion prediction equation designed for Japan seismicity and find that the spectral acceleration is well estimated for periods larger than 3 s and distances ranging from 100 to 500 km. At last, through the analysis of the displacement attenuation plots, we show that the 2011 Tohoku-Oki event is likely composed of multiple rupture patches as suggested before by time-reversal inversions of seismic data.

Keywords: Seismology

Print ISSN: 0956-540X

Electronic ISSN: 1365-246X

Topics: Geosciences