GeoIdee; GIS, Database and Software Engineering
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SCOPES workshop in Bishkek
Between October 23 and October 26 2012 the SCOPES workshop 2012 was held at the University of Central Asia (UCA) in Bishkek. Main topic of the workshop was within the scope of Spatial Data Infrastructure.
Following universities and organizations were participating:
In cooperation with the Centre for Development and Environment (CDE), GeoIdee was designing and holding most of the lectures and exercises.
| First approach of an ER model for soil sampling developed during the workshop |
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The following topics were covered during the workshop:
| Spatial Data Infrastructure (SDI) | Basics and concepts defining a SDI; institutional and technical approaches; possible levels of implementations. |
| Quantum GIS | Current stable version of Quantum GIS; new and useful plugins; hands-on training. |
| Data modeling | Principals of Entity Relationship (ER) Models; advantages and disadvantages of database approaches; examples and developing of data models based on own datasets. |
| Coordinate systems | Introduction into the EPSG database as reference for most of the coordinate reference systems in use; implementation of the EPSG database in ArcGIS and QGIS. |
| Meta data | Definition of meta data; standards used; tools for capturing and maintaining of meta data; retrieving information from data catalogues on the web. |
| Web services | Introducing to the different dialects of OGC web services such as WMS, WFS, WCS and CSW; accessing services through GIS desktop applications. |
| Open Street Map (OSM) | Concept of crowdsourcing projects; main differences of the data structure between OSMand GIS; concept of collaborative workflows; hands-on training in simultaneously data capturing. |
For all participants, and lecturer, the four days of workshop were very intense and successful. The program tried to cover a few specific topics of Spatial Data Infrastructure in relation with the specific needs in the Central Asian context.
GeoIdee office moved
During the month of August, the office of GeoIdee.ch was moved from Dushanbe (Tajikistan) to Berne (Switzerland).
The new address is:
GeoIdee, Yvo Weidmann
Ensingerstrasse 30
CH-3006 Berne
Mobile +41 79 648 59 83
During the last three years, I had the great pleasure to work on interesting and exciting projects in Tajikistan and Switzerland. The list of projects gives a nice overview of all the activities during this period.
Here some few impressions of the last three years of working activities:
I would like to thanks all the clients and their staff for their confidence and cooperation (list in alphabetic order):
- CAMP Kuhiston (Dushanbe / Tajikistan)
- Centre for Development and Environment - CDE (Berne / Switzerland)
- Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH (Dushanbe / Tajikistan)
- Deutsche Welthungerhilfe e.V. (Dushanbe / Tajikistan)
- Ernst Basler + Partner Ltd. (Zollikon / Switzerland)
- Milal-Inter (Khorog/ Tajikistan)
- Mountain Ungulates Project Tajikistan (Khorog/ Tajikistan)
- MUTTONI & BEFFA SA (Faido / Switzerland)
- Nature and Biodiversity Conservation Union Tajikistan (Dushanbe / Tajikistan)
- Nature Protection Team (Dushanbe / Tajikistan)
- NCCR North South RP11 - Land resource potentials (Berne / Switzerland)
- Safe Drinking Water Project USAid Tajikistan (Dushanbe / Tajikistan)
- WaterGisWeb AG (Berne / Switzerland)
A special thanks goes to the French GIS consultant Fabrice Lartigou. He wrote a very nice blog entry about my work in Takjikistan (in French). Read the blog here.
Land-use and pasture management map sets Baljuvon, Khovaling and Temumalik
Based on the results of the workshop about thematic mapping in Baljuvon a complete set of land-use and pasture management maps for over 30 individual watershed were produced for the natural resource management project of Deutsche Welthungerhilfe e.V. (WHH) in Southern Tajikistan.
As input for the maps the GoogleEarth-based digitized data layers were converted into a collection of several shapefiles. The attributes of the shapefiles were previously designed for the usage of the Deutsche Welthungerhilfe e.V. (WHH) project in the three project regions of Southern Tajikistan. The shapefiles are containing polygons such as pasture areas or areas with limiting factors like landslides or gullies. Other point geometry based files are containing individual water points or pasture related constructions.
The individual geometries are connected by key values to the project database. The project database provides additional information of each watershed like population, livestock or trainings provided.
The data are represented in two different maps sets:
- Pasture management map
- Map of current land use
Each mach exists in a version with a satellite image and grey-scale Soviet topographic map as background information.
| Current land use | Pasture management |
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The standardized map cover sheet (format ISO-A4)provides a standardized legend and a common layout for all watersheds. The folded maps in Tajik language are integrated as attachment to the written watershed management plans which are available for all the individual watersheds.
The data processing was done with GoogleEarth and Quantum GIS. The final compilation of the map layout was done in gvSIG. Additionally to the map production a review of the project database was conducted in combination with a training of the database administrator of Deutsche Welthungerhilfe e.V. (WHH).
GIS application for Swiss National Boundaries released
Switzerland is sharing border with 5 neighboring countries (France, Germany, Lichtenstein, Austria and Italy). About 1860 kilometers of borderline¸ based on about 32'000 individual boundary stones and backup marks, has to be managed. To manage a such large and complex data collection with legal validity needs an adequate tool.
The management of the boundary is embedded within the Federal Office of Topography swisstopo. Swisstopo, famous for the high quality mapping products of national level, uses the ESRI-ArcGIS environment for most of the task within the field of geodata management and maintenance.Swisstopo established a production infrastructure called TOPGIS to create, manage, and update the new Topographic Landscape Model (TLM) of Switzerland and the corresponding. For a seamless integration of the management of the national boundary information into the TOPGIS environment a collection of tools, realized as ArcMap-AddIn's, was developed.
The requirements of the needed tools was defined by swisstopo. During several workshops between swisstopo and WaterGisWeb Ltd. the workflow, functionality and user interface of each individual tool was specified in detail. The result of all the workshops was integrated in an detailed system specification. The development of the tools was following the guidelines of the TOPGIS environment.
The GIS database of the Swiss National Boundary is a complex relational data model containing about 30 spatial and non-spatial tables connected by 50 relationship classes. The points and lines of the boundary are organized at three levels:
- Import: Data under changes and not legally binding yet
- Productive: Currently active and legally binding boundary
- Historical: Data which are not legally binding anymore and which are redeemed by new data in the productive layer.
Besides the geometry of the boundaries, a large amount of additional information is stored, this includes damage reports and any other kinds of observations for boundary stones, treaties and amendments with the neighboring countries, contacts, information about backup survey stations, administrative order of the individual boundary stones within the system of the neighboring country and many more.
The database was developed by swisstopo using ArcGIS 10 and enhanced in close cooperation with WaterGisWeb Ltd..
To maintain the data stored in such a complex system, an adequate set of software is needed. The project was completely carried out by WaterGisWeb Ltd., GeoIdee.ch acted as freelance collaborator. The project provides an extensive set of tools embedded as AddIn in ArcGIS 10 to maintain, administrate, analyze and display the Swiss National Boundaries. The tools are realized in the programming language C#. A total of about 45'000 lines of source code (64'000 lines including comments and documentation) for 190 classes of data objects, business logic and user interfaces were written between August 2011 and April 2012.
The tools are providing help for the complete workflow of maintaining and presentation the data:
- Handling imported data. Manipulation of attributes and geometries.
- Matching and merging attributive data across the editing and the productive levels, based on a set of geometrical procedures which are highly configurable.
- Quality assurance by checking the logical and topological correctness of the data. The logical checks are based on rules which are stored in the database and may be adapted if needed.
- Transfer of modified data from the import level into the productive level and historicizing redeemed data. Appling logical an topological tests to assure database consistency.
- Administration of damage reports and any other kinds of observations which are related to one or many boundary stones. Documents, such as pictures or reports can be connected to the stones and retrieved by the application.
- Visualization of all information connected with boundary stones by selecting graphically individual or groups of objects.
- Exporting of coordinate lists of defined sections following specific rules of topology. The export includes a standard set of attributes. Additional attributes to be exported can be defined by the user.
- Creating and updating annotations for individual features at different map scales placed with high cartographical quality. The annotations are based in individual defined attributes and can be freely placed within the map regarding the best representation in combination with other background information.
The complete toolset was successfully tested by swisstopo and released into production by End of April 2012.
Locally optimized transformation parameters for Pulkovo-1942 datum
The Soviet topographical maps are a highly detailed source of information for many fields of research, engineering and natural resource management. In combination with accurate satellite imagery and GPS measurement highly valuable baseline information can be derived.
The topographical maps are based on the geodetic datum of Pulkovo-1942 and the ellipsoid of Krassowski-1940. For several reasons an adequate transformation parameter set between the WGS-1984 and the Pulkovo-1942 is not available for Tajikistan. The EPSG database v7.11 provides about 21 different versions of parameter sets. But unfortunately, none of them is accurate enough to combine the Soviet topographical maps in Tajikistan with satellite imagery and GPS measurements based on the WGS-1984 datum. Additionally, local distortions of the base coordinate frame caused by the triangulation methods adds errors to the consistency between the different data sources.
One possible solution to overcome these shortcomings is the calculation of locally optimized transformation parameters between the WGS-1984 and the Pulkovo-1942 datum. For several regions of Tajikistan, such optimized parameters were calculated based on the equation of the Standard Molodensky Transformation.
 | The Standard Molodensky Transformation is based on a shift of the coordinates along the 3 axis with the values dx, dy and dz. As input for the calculations to retrieve the three Molodensky parameters, several identical points were measured in ellipsoidal coordinates of the WGS-1984 and Krassowski-1940 ellipsoids. The three parameters were derived by using least squares adjustments. Depending on the quality of the input data, the 7-Parameters of the Coordinate Frame Rotation or Position Vector Transformation methods could also be provided. |
The following vector field shows the improvement between the standard geocentric translation applied in Tajikistan (left) and the locally optimized Molodensky parameter set (right). The control points were measured in high resolution orthorectified satellite imagery (WGS-1984) and topographical maps 1:50'000 (Pulkovo-1942).
| Existing Geocentric Translation EPSG 1254 | Locally optimized Molodensky parameter |
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The systematic shift of the coordinates caused by the EPSG 1254 transformation was fully removed. The average residuals of the control points were reduced from 53m to 16m. The fitting accuracy of the satellite imagery and GPS measurement was significantly increased.
In another region the vector field of the residuals is showing similar effects. The systematic shift of the coordinates in Western direction was largely removed and the average residual error was reduced from 85m to 21m. The significant difference of the vector directions between the first and the second example may result from local distortion of the base coordinate frame.
| Existing Geocentric Translation EPSG 1254 | Locally optimized Molodensky parameter |
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The method applied can be used in project regions where Soviet topographical maps and satellite imagery with GPS-based field observations shall be combined. It also can be used for the transformation of digitized data layers which are based on the Pulkovo-1942 datum into WGS-1984-based reference systems such as the new coordinate frame of Tajikistan.
 | The calculated transformation parameters can be applied in all standard GIS software packages such as ArcGIS, Quantum GIS or gvSIG. For ArcGIS users the transformation set can be stored as Custom Geographic Transformation file (*.gtf file) which can be distributed among the users of an organization. The *.gtf file can be directly used within the user interface of ArcMap and will be applied to all data sets in the data frame. |
The use of topographical maps at a scale of 1:25'000 or above could improve the quality of the calculation of the parameter sets considerably. GeoIdee.ch offers the calculation of optimized parameters as service, please feel free to contact.
Contact
Yvo Weidmann
Ensingerstrasse 30
CH-3006 Berne
Switzerland
Mobile +41 79 648 59 83
Mail yvo (dot) weidmann (at) geoidee (dot) ch
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