Bashkim IDRIZI Ismail KABASHI NEW GEODETIC REFERENCE FRAME KOSOVAREV 01
Overview: Basic data of the Republic of Kosova Geodetic referent frame before year 2001 KOSOVAREF 01 KOSOVAREF 01 1 st order Observations Link with EUREF permanent network KOSOVAREF 01 2 nd order Transformation parameters Transformation of cadastral data to KOSOVAREF01 Proposal for active GNSS network Appendix: 1st order network of points in KOSOVAREF01
Basic data of the Republic of Kosovo Area: 10908km 2 Border line: 744km Municipalities: 30 Cities: 30 Local cadastral offices: 30 Cadastral zones: 1301 Cadastral parcels: 2milion Private property: 57% State property: 43% Geodetic points 1 st order: 32 Geodetic points 2 nd order: 397 Point Geographic coordinates φ λ North 43º16 07.5 N 20º49 01.9 E South 41º50 50.1 N 20º37 36.8 E East 42º38 48.0 N 21º47 42.7 E West 42º44 10.4 N 20º01 10.9 E Center 42º33 28.8 N 20º54 26.8 E
Geodetic referent frame before year 2001 Part of former Yugoslavia federation Horizontal network Trigonometric networks in 4 orders Urban networks Vertical network IINVT II leveling of high accuracy Parameters of the coordinate system: Datum Hermannskogel Ellipsoid Bessel (1841) Map projection Gauss-Krüger (3 zones) Central meridian 21 E Prime meridian Greenwich Prime parallel Equator Scale factor 0.9999 False easting 500000m False northing 0m Elevation origin Mean sea level Molo Sartorio, Trieste, Italy. Units Meter (m)
KOSOVAREF 01 Established on year 2001 as Kosova Referent System KOSOVAREF01 Reference network of Kosova in 3 orders 1 st orders is in state level, 2 nd and 3 rd are local networks within the municipalities and centers. Coordinate system has bellow parameters: Datum ETRS89 Ellipsoid GRS 80 Map projection Central meridian Prime meridian Prime parallel Gauss-Krüger (3 zones) 21 E Greenwich Equator Scale factor 0.9999 False easting False northing Elevation origin Units 7500000m 0m Mean sea level Molo Sartorio, Trieste, Italy. Meter (m)
KOSOVAREF 01 1 st order Consists 32 points, 22 existing points of the trigonometric network 10 new points. Homogenous network Distances between points 15-25km Period of observations: March 20 to April 12, 2001. All points checked before measuring. 5 points had to be moved in safe areas. Evaluated by long baseline calculations with EPN inbound and adjustment. Accuracy:
Measurements in 8 sectors separately. Link between sectors by using of the neighboring points along border. For reliability second campaign after 1.5 week. Center point: FK01 in Fushe Kosova.
Details of measurements
HIGH OBSERVATIONS 23 of 32 1 st order reference network points were connected by static GPS measurements, to orthometric highs from 11 (eleven) former FYR IINVT points. Measurements of excentrums (where needed): with Leica NA 3002 Selection of points in relation to former high reference points: High range from about 100m Maximum distance 15km.
Geoid ondulatinos were calculated based on European Gravimetric Geoid 1997 (EGG97) with resolution 1.5x1. Differences between ellipsoidal highs, leveling and geoid, are shown in the table. Differences between ellipsoidal and leveled hights are from 44.19 to 45.62m, which theoritacly should correspond to geoid (h ell -h level =geoid) Residuals comparing of EGG97 in Kosovo, shown in last column of table and in next map.
Some systematic behavior of the residuals: - in the eastern part generally a negative difference was detected, - in the western part it was the oposite. The differences can either be: - due to the geoid (anomalies, offset and/or slight tilt), which might not be specific enough for these local studies, or - due to errors in the levelled heights. After some investigations, it was found out that only for three of the eleven used height reference points adjusted IINVT values were available!
Link of KOSOVAREF 01 1 st order with EUREF permanent network (EPN): Remark: Not overlapping with the networks on neighboring countries (Macedonia, Albania, Montenegro and Serbia)!
KOSOVAREF 01 2 nd order Period of measurements: June 2001 November 2002. Consist: 397 points. Measurement details: Sessions: Referent stations 2sesions per day, in different periods of day 2-3 stations in points of 1 st order Measuring window Measuring duration Recording interval Minimum elevation Checked min. 5 Satellite by SKI PRO Almanac, GDOP<5 1 hour 5sec 15degrees Time needed 1 session per 1 day, 2 sessions = 2 days Personal resources 3 teams Used equipment Leica GPS receivers 520 and 530 with Leica AT502 antennas
Defining of global transformation parameters Translations: ΔX=628.54052m, ΔY=192.25380m, ΔZ=498.43507m Rotations: ε X = -13.79189, ε Y = -0.81467, ε Z = 41.21533 Scale: m=-17.40368ppm The "global" 7 parameter transformation is not able to care for local distortions!
Transformation of cadastral data to KOSOVAREF 01 using Finite Element Method The finite element method is an appropriate method for homogenous and reversible transformations without gaps or distortions. The workflow for the Kosovo transformation project: 1.Provisional triangle network 2.Determination of distortion vectors 3.Improvement of the transformation base 4.Transformation of cadastral data 5.Quality checks
ITERATIVE APPROACH TO THE TRIANGLE NETWORK DESIGN Definition of the triangles: iterative process. The first draft of the triangle network : 54 triangles. The final triangle network: 113 triangles. Map used for the planning of measurement campaign with provisional triangles, color distinctions according need for additional measurements
Period of measurements: January-August 2003.
The comparison of the transformed with the measured coordinates shows - residuals (brown) of a global Helmert transformation, -26 pass points (red) - areas with systematical distortions (green)
Borderline Effects Fictitious Transformation Base Points Transformation of Checkpoints The average of the residual vectors of all transformed checkpoints reached is 0.19m with a mean deviation of 0.10m. The triple length of the average vector (0.57m) was used to set a tolerance for the detection of gross errors. Map with Fictitious Triangles (orange), used to cover the border area of Kosovo (gray)
Modification of Triangles Final Triangle Network Residuals Map with changed TBPs to get smaller, unsystematically distributed residuals in the concerned area. -orange: new triangle -with brown: new residuals, -red: old definition -green: residuals of old definition. Residuals of checkpoints after transformation with final triangle network definition
Residual vectors of checkpoints and quality over different stages of transformation.
Map with distortion components of stretching/compression (blue) and dilation (red), area of heterogeneities marked by arrows
TRANSFORMATION OF CADASTRAL DATA In the case study, where transformed coordinates were compared with new measured coordinates, an average difference of 0. 1 0. 15cm could be detected. -the effect of transformation on the areas of parcels is neglectable relative to the errors of vectorization, original surveying data, drawing and distortion of cadastral plans. -even in areas where residuals were big and distorted after transformation, the relatively small area of parcels was not affected. - The apparently big maximum area residual of 320.6m 2 of a parcel in the cadastral zone Strpce in Strpce municipality is relatively small compared with the size of this rural parcel of 9.9km 2!!!
PROPOSAL FOR ACTIVE GNSS NETWORK OF KOSOVA
APPENDIX 1 st order network of points in KOSOVAREF01 in Kosovo
In behalf of coauthors, Bashkim IDRIZI & Ismail KABASHI THANK YOU FOR YOUR ATTENTION!!!
Bashkim IDRIZI Ismail KABASHI NEW GEODETIC REFERENCE FRAME KOSOVAREV 01