DEVELOPMENT OF CROATIAN NATIONAL REFERENCE FRAME Republic of Croatia State Geodetic Administration
Željko BAČIĆ, State Geodetic Administration, Zagreb,
[email protected] Tomislav BAŠIĆ, University of Zagreb, Faculty of Geodesy,
[email protected] Marijan MARJANOVIĆ, State Geodetic Administration, Zagreb,
[email protected]
University of Zagreb - Faculty of Geodesy Department for Geomatics
Abstract
Basic Gravimetric Network
RP388
RP389
The establishment of a new reference network of the Republic of Croatia through re-computation of international GPS campaigns carried out in 1994, 1995 and 1996 and recognising new solution within Resolutions of the EUREF Symposium in Dubrovnik in 2001 as combined EUREF-CRO94/95/96 solution for Croatia the required basis for further development of national reference frame was fulfilled. Also, the project Restoring of the Trigonometric Network of the II. order and Establishing the Homogenous GPS Network 10 x 10 km was finished in 2002. Following the EUREF recommendations, the ETRS89 will be accepted as new geodetic datum of the Republic of Croatia in a very near future. At State Geodetic Administration the Intranet database system of the geodetic points included all alphanumerical and graphical data was finished at the end of 2003 with goal to enable access to data by way of Internet for all users till the end of year 2004. The new national gravimetric network included 36 first order points observed with SCINTREX gravity meters in 2003 will be conected to the national levelling and reference GPS network. Also, due to strategy of periodical controll of national reference GPS network, ten EUREF sites observed in 1994 will be re-observed in 2004.
RP214 RP1209
46
RP404
Combined SLOCRO-94
CROREF-95
CROREF-96
9.3
1.3
4.5
East
3.0
2.2
3.6
3.0
Up
6.3
7.9
3.4
6.7
Number of Stations
105
24
32
97
RP249 RP248
RP197
RP363 RP362
RP101
RP258
RP728
RPG528
RP189
RP5011 RP050
RP188
5.1
RP391
RP194 RP5002
RP182
Croatian Reference GPS Network
North
The Basic Gravimetric Network of the Republic of Croatia consist of Gravimetric Network of 0. order and Gravimetric Network of 1. order. The Gravimetric Network of 0. order (Absolute Gravimetric Network) was established within UNIGRACE Project (Unification of Gravity Systems in Central and Eastern Europe) in period 1996-2000 and consist of 6 points (Zagreb-Puntijarka, ZagrebMaksimir, Pula, Osijek, Makarska and Dubrovnik). The Gravimetric Network of 1. order consist of 36 points, 25 of them are taken over from old gravimetric network and 11 are new points. The zero series gravimetric measurements of Basic Gravimetric Network were performed in period 12. 06. 2003. – 13.08. 2003. in five phases with two SCINTREX CG3M relative gravity meters. After preprocessing, the data were adjusted by method of least squeres and estimated accuracy is ±7.51 x 10-8 ms-2 (Bašić et al, 2003).
RP402
RP020
RP187
Parameter
RP316
RP210
RP196 RP384
RP185
RP180
45
The base of Croatian Reference GPS Network are GPS Campaigns carried out in 1994, 1995 and 1996 in the Republic of Croatia and the Republic of Slovenia observed with purpose to establish a connection to the EUREF reference system. The Project of establishment of homogenous GPS-point-network 10 x 10 km started in 1997 and continued in 2002 was completed in the year 2003. After re-computation of EUREF and CROREF GPS campaigns carried out in Croatia and Slovenia in 19941996 in ITRF1996, epoch 1995.55 (Marjanović, Bačić, 2002) and accepted of new solution within Resolutions of the EUREF Symposium in Dubrovnik in 2001 as combined EUREF-CRO94/95/96 solution for Croatia new common adjustment of GPS-point-network 10x10 km in ITRF1996, epoch 1999.60 were computed (Bašić et al, 2002). RMS values with respect to the combined EUREF-CRO94/95/96 solution (individual campaign solutions – combined solution) in millimeters are:
RP222
RP401 RP375
RP215
RP235
RPG601 RP289
The Croatian Reference GPS Network consist of 1101 points: GPS PROJECT
TOTAL POINTS
EUREF-CRO94/95/96
78
GPS network 10 x 10 km
1023
RP579
RP287
RP5003
44
RP525
RPG649
RP547 RP294
RPR13 RP731
RP5013
RP301 RP5004 RP303
RPR96A
Within both GPS projects totally 238 trigonometric points of I and II order were observed and new transformation parametars between ETRS89 reference system and official Croatian coordinate system (HKDS) have been determined. The parametars confirm previously defined non-homogeneous of existing trigonometric network. Completing Croatian Reference GPS Network practical conditions for establishment of new Croatian National Reference Frame and new geodetic datum have been fulfilled.
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43
RPG822 RPG825
RP5008 RP733A RP733
The data are stored in Oracle Database System in combination with ESRI ArcGIS software in order to performe connection with the Register of Spatial Units Database and digital maps 1 : 25 000. In order to fulfill planned functionality of database following processing steps were carried out: 1. Input of alpha-numerical data,
GT1 20 GT122
GT1 21
GT11 9
GT1 06
GT1 11
GT102
GT1 07
GT10 1
GT10 9
GT116
GT105
GT12 4
45
GT123
GT103
GT1 25 GT126
GT12 7 GT128
GT129
44 GT130 GT131 GT132 GT133 GT134
43
GT1 36
Reference GPS Network 14
15
16
17
18
19
42 13
Basic Gravimetric Network 14
15
16
17
18
19
Transformation Programs New Point Description (Digital Form)
In order to provide unified computation procedures of GPS measurements and coordinate transformations State Geodetic Administration contracted Faculty of Geodesy in Zagreb to develop two computer programs (Bašić et al, 2003). The first program is DAT_ABMO for transformation between ETRS89 and Croatian national coordinate system. The second program is IHRG2000 for computation of geoid undulations for transition from elipsoidal heights to ortometric heights.
Program DAT_ABMO
Main Menu
The purpose of program DAT_ABMO is to provide users to transform the coordinates between different coordinate systems, different reference epochs and different geodetic datums. It is possible to transform coordinates by using sets of default transformation parameters or by using transformation parameters computed on the base of identical points in both coordinate systems.
Projects
Coordinate Systems
Trigonometric and GPS Points
GT104
GT10 8 GT11 5
GT118
GT135
Old Point Description (Analog Form)
Gravitiy Points
Transformation Parameters
2. Double control of entered alpha-numerical data,
GT110
RP734
1. Application for input and updating of data (Intranet Application), Cadastre Officies
GT1 13
GT117
RPG859
Main Menu of Intranet Application
3. Application for publishing and distribution of data (ArcGIS Application).
46
RP5005 RPG872
In year 2002 the State Geodetic Administration started the project of development and establishment a central geodetic point database. After developing process of database model, three different applications were finished: 2. Application for Export and Import a large amount of data,
GT112 GT1 14
RP5009
42 13
The Database of Geodetic Points
1st General Assembly Nice, France, 25 - 30 April 2004 G7 Reference Frame Definition, Influence of Geophysical Fluids, and Combination of Space Geodesy echniques
Height Points
3. Scanning of old point descriptions, 4. Input of graphichal data into database, 5. Connection of alpha-numerical and graphical data of geodetic points, 6. Connection of geodetic point database with Register of Spatial Units Database and digital maps 1 : 25 000.
Diagram of Data Input Process and Database Application USER 1
USER 2
Program IHRG2000
ArcGIS Application
The program IHRG2000 is designed for computation of geoid undulations for transition from elipsoidal heights to ortometric heights. It is possible to compute geoid unudaltion of any point on the territory of the Republic of Croatia.
USER n
INPUT OF ALPHANUMERCIAL DATA
References:
DATABASE SERVER
Bašić, T., Rezo, M., Markovinović, D. (2002): Unique Adjustment of 10 km-GPS Network of the Republic of Croatia, Faculty of Geodesy, University of Zagreb, 2002.
INPUT OF GRAPHICAL DATA
On the basis of alpha-numerical and graphical data stored in Oracle Database System, within ArcGIS Application it is possible to produce new point description forms in digital format (MS Word Document or PDF File) for selected number of points.
ADMINISTRATOR
OPERATOR 1
OPERATOR 2
Bašić, T., Rezo, M., Markovinović, D. (2003): Basic Gravimetric Network of the Republic of Croatia, Faculty of Geodesy, University of Zagreb, 2003. Bašić, T., Šljivarić, M., Rezo, M., Markovinović, D., Jeličić, J. (2003): Development of Programs for Application of Official Croatian Geoid and Coordinate Transformation between HDKS-a i ETRS-a, Faculty of Geodesy, University of Zagreb, 2003. Marjanović, M., Bačić, Ž. (2002): Computation of the Combined Solution of EUREF GPS Campaigns in the Republic of Croatia, Report on the Symposium of the IAG Subcommission for the European Reference Frame – EUREF in Dubrovnik, May 16-18, 2001, p. 171-188, Frankfurt/Main, 2002.
