By Ing. Hermogenes Suarez.
Twenty years ago, the first Venezuelan geoid model named GeoidVen (Hoyer et al. 2002) was presented and published. The development of the said model has been achieved thanks to the effort of Scientists, Professors, and Engineers and the meticulous work and collaboration of a dedicated group of students from the School of Geodetic Engineering of the University of Zulia (EIG-LUZ).
In this article, we will try to tell a part of the history behind the geoid of Venezuela and its relationship with the students of the EIG-LUZ to highlight the role and importance of the student presence in each research center.
In the year 1996, when I was just a student of the first subject of Geodetic Engineering, I came across a communication in the “A” wing of the Faculty of Engineering of the University of Zulia, which summoned those students interested in being part of the research activities of the Geodetic Astronomy Laboratory (LAG) of the Higher Geodesy Department (DGS).
Days later, I was sitting across from Prof. Dr. Melvin Hoyer in his office in what would be my first “geodesic” job interview. My esteemed colleague and friend Ing. José Azocar accompanied me on that occasion. The interrogation was tense and detailed, but fortunately, we were both selected and immediately incorporated into the group of LAG/DGS student collaborators. By then, many of the student collaborators of the LAG/DGS were already close to graduating, so a group of new collaborators who make up the replacement generation had to enter and train.
At that time, collaborating students received financial aid from the funds allocated for the projects. For some students, these aids were a lifesaver; to a certain extent, these resources guaranteed the permanence or continuity of studies at the university. Dozens of students had the privilege of being trained and being part of what would later (1997) become the prestigious Physical and Satellite Geodesy Laboratory (LGFS) of the University of Zulia (LUZ).
The activities at the LAG/DGS were diverse and all very interesting; it was like coming into contact with a new universe of experiences and knowledge. Students participate in field measurement projects with the most sophisticated instruments of the time (GPS, RTK, MARA, PRARE, etc.). At the end of the 90s, one of the most important projects of the LAG/DGS was the determination of the Geoid of Venezuela. It was a national project entrusted by the National Cartography Directorate -DCN (currently IGVSB).
For the calculation of the geoid model, a digital elevation model (DTM) was required that covered the entire national territory. By the mid and late 90s, said DTM was unavailable; therefore, Prof. Dr. Eugen Wildermann developed a methodology to manually extract the heights of the topographic charts from the DCN. These heights were recorded on paper templates, which underwent rigorous quality control. Later, all these values were manually entered into the computer and incorporated into a database from which a digital elevation model (DTM) was generated.
Prof. Dr. Eugen Wildermann, in charge of coordinating this effort, developed a series of programs in Fortran language for processing the raw data, but also trained several students (including me) in programming and thus helped in the automation of this process. and other projects.
However, manual work was unavoidable and had to be tackled rigorously and quickly, as the project clock was ticking. It was there that the participation of an army of EIG-LUZ students of various generations during the ’90s was in charge of the manual extraction and quality control of hundreds of paper records, the manual entry of thousands of dimensions in an orderly manner in a database for finally, its corresponding processing and generation of the DTM. This way, Venezuela’s first digital elevation model was generated, essential for calculating GeoidVen (Hoyer et al. 2002).
On the other hand, for this project, it was necessary to carry out a series of GPS measurement campaigns and conventional leveling to generate geoid undulations on some points of the first-order leveling network in Venezuela. These GPS campaigns, which had national coverage, involved a great effort of logistics and involved dozens of EIG students, thesis students, and some practical professional works.
In 2003, without ever having imagined it, I had the opportunity and the privilege of being in charge of calculating the 3rd geoid model for Venezuela, the MGCV04 (Hoyer et al. 2004).
At that time, a renewed army of collaborating students was needed to program routines in Fortran, Matlab, and GMT languages, which would serve in the preprocessing and processing of gravimetric measurements, GPS, and BM’s, among others. This group of students was in charge of monitoring day and night the intensive processing sessions that took days or weeks due to the amount and density of data to be processed. They were also in charge of designing graphs and maps to visualize and analyze the results.
Already in the last stage of the project, together with the group of collaborating students, we dedicated ourselves to designing and developing the geoid undulation interpolation software GEOIDVEN V.1.4 (Suárez et al. 2005). Among these students were Humberto García, Henry Codallo, Jorge Pérez, José León, and Victor Cioce. During 2003 and 2005, this group of students as authors and co-authors of more than ten scientific works related to calculating the geoid. Naturally, all this work was closely coordinated and supervised by the scientific body of the LGFS.
Fortunately, the MGCV04 geoid model and the GEOIDVEN V.1.4 software had a good reception, being awarded and recognized on several occasions by the national scientific community. But the most outstanding thing is that the MGCV04 was made official by the IGVSB and immediately incorporated into topographical and geodetic works throughout the national sphere, especially in the oil industry. Several geodetic and/or geophysical software incorporated the MGCV04 into their libraries and routines.
Thanks to the vision of Prof. Dr. Hoyer and Prof. Dr. Wildermann, many students had the privilege and opportunity to train and develop skills beyond the academic program. The participation of the students in the teaching, research, and extension work of the LGFS was essential for the success of many projects, and in particular, for the formation of a highly specialized human resource that would later end up being the next generation and would give it continuity. and projection to a whole geodesic legacy inside and outside Venezuela, among them the Professors: Victor Cioce, Luz Bacaicoa, María Virla, and Ileanis Arenas.
Finally, my appreciation to all the professors of the DGS/LGFS and to those collaborating students who still live today in each research center because the future of geodetic engineering lies with them. Students are the reason and essential part of the academy, and our mission is to guide and inspire them to explore paths that probably no one has traveled before.
References:
- Hoyer M, Wildermann E, Acuña G, Hernández J, Nahmens A, Velandia J (2002) Determination of the geoid in Venezuela by placing least squares. Proceedings of the International Congress of Geodesy and Cartography. Caracas Venezuela.
- Hoyer M, Wildermann E, Suarez H. Hernandez J (2004). Combined Geoid Model for Venezuela (MGCV04). December 2004, INTERCIENCIA, Vol. 29, No. 12, Pages 667-672.
- Suarez H, Garcia H, Cioce V, Hoyer M, Wildermann E (2005). Software for the interpolation of geoid undulations from the MGCV04 model. XI Conference Scientific Engineering Techniques. Maracaibo Venezuela.
