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Geodetic and geodynamic studies at Department of Geodesy and Geodetic Astronomy WUT

Brzeziński A., Barlik M., Andrasik E., Izdebski W., Kruczyk M., Liwosz T., Olszak T., Pachuta A., Pieniak M., Próchniewicz D., Rajner M., Szpunar R., Tercjak M., Walo J.

Reports on Geodesy and Geoinformatics

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2016

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Vol. 100

165--200

EN

The article presents current issues and research work conducted in the Department of Geodesy and Geodetic Astronomy at the Faculty of Geodesy and Cartography at Warsaw University of Technology. It contains the most important directions of research in the fields of physical geodesy, satellite measurement techniques, GNSS meteorology, geodynamic studies, electronic measurement techniques and terrain information systems.

2

Analiza stanu kształcenia na kierunku geodezja i kartografia

Banasik P., Walo J.

Przegląd Geodezyjny

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2014

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R. 86, nr 4

3--10

PL

Po 1989 roku nastąpiły istotne zmiany w szkolnictwie wyższym w Polsce. Przede wszystkim znacznie wzrosła liczba studentów oraz liczba szkół wyższych zarówno publicznych jak i niepublicznych. Zmiany te dotyczą również kształcenia na kierunku geodezja i kartografia. Z informacji uzyskanych z Ministerstwa Nauki i Szkolnictwa Wyższego wynika, że obecnie istnieje 27 szkół wyższych (14 publicznych i 13 niepublicznych) kształcących na kierunku geodezja i kartografia, które przyjmują corocznie ponad 4000 kandydatów. W artykule podjęto próbę analizy stanu kształcenia na kierunku geodezja i kartografia. Dane do analizy zaczerpnięto z ankiety obejmującej informacje na temat programów kształcenia, rodzajów prowadzonych studiów, liczby studentów, kadry naukowej, rekrutacji i bazy dydaktycznej. Z analizy wynika, że w większości uczelni kształcenie jest na dobrym poziomie. Są jednak takie uczelnie, które nie mają własnej kadry dydaktycznej oraz podstawowego wyposażenia laboratoriów. Warto też zauważyć, że znaczny wzrost liczby studentów w ostatnich latach może spowodować, że w przyszłości nie wszyscy absolwenci znajdą zatrudnienie w wyuczonym zawodzie.

EN

After 1989, there have been significant changes in higher education in Poland. First of all, the number of students as well as the number of higher education institutions both public and non-public increased significantly. These changes also affected the education in the field of geodesy and cartography. Information obtained from the Ministry of Science and Higher Education shows that currently there are 27 schools (14 public and 13 non-public) educating in the field of geodesy and cartography, which take in more than 4000 candidates annually. The paper attempts to analyze the state of education in the field of geodesy and cartography. Data for the analysis was derived from the survey, including information on education programs, types of studies conducted, the number of students, academic staff, recruitment and laboratory equipment. The analysis shows that in the majority of university education is at the good level. However, there are such schools that do not have their own teaching staff and the basic equipment of the laboratories. It should also be noted that a significant increase in the number of students in recent years may cause some difficulties for graduates in finding employment in their profession.

3

Quality Indicator for Ionospheric Biases Interpolation in the Network RTK

Próchniewicz D., Walo J.

Reports on Geodesy

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2012

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z. 1/92

7--21

EN

This paper presents the methodology and performance of an ionospheric quality indicator in the Network RTK. A new index called Zenith Ionospheric Residual Interpolation Uncertainty, which is an extension of the existing indicator is proposed and evaluated using the reference station test network. The dataset used for this study was collected during ionospheric storm period in order to test the indicator during disturbed ionospheric conditions. The test results show that the proposed indicator provides a realistic prediction of ionospheric interpolation accuracy and can be used to predict the Network RTK performance at rover location.

4

Research on absolute gravity variations in geodynamic laboratory in Książ in the period of 2007-2011

Kaczorowski M., Olszak T., Walo J., Barlik M.

Artificial Satellites : Journal of Planetary Geodesy

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2012

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Vol. 47, No. 4

169--176

EN

In 2006 a gravimetric pavilion was installed inside the Geodynamic Laboratory (LG) in Książ. The pavilion was equipped with two pillars intended to serve relative and absolute gravimetric measurements. Installation of measurement platform for absolute gravity measurements inside gravimetric pavilion of LG made it possible to perform four sessions of absolute gravity measurements: two of them in 2007 (June 10-12 and Nov. 21-22), one in 2008 (Apr. 21-22) and one in 2011 (June 19-21). In 2007 the absolute measurements were performed using two FG5 ballistic gravimeters. In April 2007 the measurements were performed by Dr Makinen from Geodetic Institute of Finnish Academy of Science with application of FG5 No. 221 absolute gravimeter. In June 2007 and in the years 2008 and 2011 such gravimetric measurements were performed by the team from Department of Geodesy and Astronomical Geodesy of Warsaw University of Technology using FG5 No. 230 absolute gravimeter. Elaboration of observation sessions from both gravimeters was performed in the Department of Higher Geodesy following the procedures used in constituting of uniform gravimetric system of geodynamic polygons reference. This constituting of gravimetric system comprised inter alia application of identical models of lithospheric tides (global model by Wenzel, 1997) and ocean tides (Schwiderski, 1980) (reduction of absolute measurements with tidal signals). Observations performed during summer of 2007, autumn of 2007, and spring of 2008 and 2011 indicated existence of small changes of absolute gravity of the order of 1 Gal. Maxima of accelerations appear in the spring period, and minima in the autumn period. This effect is connected with the influence of global hydrological factors the annual amplitude of which is ca 1,5 Gal and achieve extreme values in the spring-autumn interval. Very small value of observed amplitude of gravity changes in the period of extreme variability suggests that the observed gravity changes in LG are caused only by global phenomenon. This proves high degree of „independence” of gravimetric measurement base in LG from the local environmental factors such as ground water level variations, ground humidity, impact of snow cover, etc. At this moment the instrumental environment of absolute measurements obtains particular value, especially in the case of the tiltmeters and relative the gravimeter Lacoste&Romberg (LR-648). The relative gravity measurements as performed simultaneously with absolute gravity measurements enable us to determine the local tidal ephemeredes which makes it possible to replace the global tidal modal with ocean tidal model with the more realistic, locally determined tidal parameters (the local tidal ephemeredes).

5

Geodynamical investigations in the Pieniny Mountain in 1994-2010

Walo J., Pachuta A., Próchniewicz D., Szpunar R., Olszak T., Barlik M.

Reports on Geodesy

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2011

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z. 2/91

29-36

EN

Geodynamical investigation in the Pieniny Mountain (south of Poland) were carried out since the 1960s. They contained levelling, gravimetric measurements and distance observations in horizontal network. The results reveled vertical and horizontal movements of the crust and periodic changes in gravity. In 1994-1995 horizontal network was adapted to perform GPS observations and they were carried out with leveling, gravimetric and EDM observations. In 1990s, the Dunajec river dam and the water resorvoirs in Czorsztyn and Sromowce Wyżne have been built. This has a new aspect in investigations releted to the effect of tectonic movements on the dam. Taking that into account, the study was revived, after six year break, in 2001. The investigations, which contain GPS, gravimetric and leveling observations, have been carried out every year. In this paper the result of horizontal displacement obtained from GPS measurement as well as gravity changes in 1994-2010 period are presented and yields linear trend in north-east direction less than 1 mm/year.

6

Geodezja na biegunach

Pachuta A., Adamek A., Kurczyński Z., Walo J., Węzka K.

Geodeta : magazyn geoinformacyjny

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2011

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nr 5

42-47

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Unified gravimetric reference frame for Polish IGS/EPN stations and geodynamic test fields

Walo J., Olszak T., Pachuta A., Próchniewicz D., Szpunar R.

Reports on Geodesy

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2010

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z. 1/88

105-113

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Scientific expeditions to Antarctic and Spitsbergen with the participation of scientists from Faculty of Geodesy and Cartography, the Warsaw Universitety of Technology (WUT)

Pachuta A., Walo J., Adamek A., Rajner M., Węzka K., Próchniewicz D.

Reports on Geodesy

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2010

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z. 2/89

21-30

9

Stacja referencyjna w Hornsundzie (Spitsbergen) : wybór lokalizacji, perspektywy rozbudowy i wykorzystanie

Węzka K., Paśnikowski M., Walo J.

Biuletyn Wojskowej Akademii Technicznej

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2010

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Vol. 59, nr 2

179-195

PL

Głównym celem projektu realizowanego podczas wyprawy na Spitsbergen w 2008 roku była analiza funkcjonowania stacji referencyjnej w Hornsundzie, w celu wyboru jej odpowiedniej lokalizacji. W 2005 roku podczas wyprawy studentów i pracowników Wydziału Geodezji i Kartografii na Spitsbergen w fiordzie Hornsund została uruchomiona stacja referencyjna. Analiza obserwacji zgromadzonych na stacji w pierwszym okresie jej pracy wykazała znaczny efekt wielodrożności sygnału. Efekt ten okazał się na tyle duży, że zdecydowano o przeniesieniu anteny w inne miejsce. Jednak z uwagi na trwającą rozbudowę bazy, zmianę lokalizacji anteny zaplanowano dopiero po skończeniu prac remontowo-budowlanych. Podczas wyprawy w 2008 roku wybrano zatem docelową lokalizację spełniającą warunki prawidłowego ustawienia anteny stacji referencyjnej. Wykonano także serię dwunastu dobowych obserwacji testowych, które pozwoliły na wstępne wyznaczenie pozycji stacji oraz analizę jakości sygnałów GNSS. Praca prezentuje analizę porównawczą obserwacji zgromadzonych w starej i nowej lokalizacji anteny oraz zawiera opis otoczenia i jego wpływ na błędy wielodrożności sygnału. Autorzy przedstawiają ponadto przykład wykorzystania stacji referencyjnej w Hornsundzie oraz planowaną koncepcję rozbudowy systemu stacji referencyjnych dookoła Spitsbergenu.

EN

Determination of a new proper location of the reference station based upon the analysis of the existing point was the main aim of the project which was conducted during the expedition to Spitsbergen in 2008. The existing reference station in the Hornsud Fjord was activated during the expedition in 2005 by the students and research workers of the Faculty of Geodesy and Cartography. The analysis of the observation gathered during the first period of the station's activity demonstrated significant multipath effect, which appearance occurred high enough to force the change of the location of the reference station. Because of the modernization of the polar station where the reference point is located, the determination of the new location of the antenna had to start after finishing the building works. Therefore during the expedition in 2008, the final location of the reference station, where conditions comply with the requirements, was chosen. Additionally, a series of twelve 24-hour long measurements were conducted, which allowed to determine the position of the new station and to analyze the quality of the GPS signal. This paper presents the comparative analysis of the observation collected in two locations of the station. It also contains the description of the surrounding environment and its influence on the multipath effect. Furthermore, the authors present the possibilities of usage of the reference station in Hornsud and deliver the concept of developing a system of the reference points around Spitsbergen.

10

Utilization of the ASG - EUPOS system NAVGEO service in monitoring displacement

Próchniewicz D., Szpunar R., Walo J., Patucha A.

Reports on Geodesy

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2009

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z. 2/87

337-342

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Determining the mutual location of mobile objects using the ASG-EUPOSS system

Szpunar R., Próchniewicz D., Walo J.

Reports on Geodesy

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2009

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z. 2/87

391-396

12

Multipath effect analysis on selected points in control network "Wióry"

Szpunar R., Walo J., Próchniewicz D., Woźniak M.

Reports on Geodesy

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2008

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z. 1/84

87-92

EN

Geodetic networks are a basic constructions periodically measured on engineering constructions. They usually joint two objects: control objects and reference objects. Physical points and geodetic observations realize it. Moreover, the reference points and control points have to be checked for their stability and measuring technique (visibility between reference and control points for terrestrial observations, multipath effect for satellite obseryations). Multipath effect analysis on selected points in control network "Wióry" is presented in the paper.

13

Jednolity system grawimetrycznego odniesienia polskich stacji permanentnych GNSS i poligonów geodynamicznych - część dolnośląska

Olszak T., Pachuta A., Próchniewicz D., Szpunar R., Trojanowicz M., Walo J.

Acta Scientiarum Polonorum. Geodesia et Descriptio Terrarum

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2008

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Vol. 7, nr 4

45-66

PL

W latach 2006–2007 założono na obszarze Polski sieć punktów bezwzględnych pomiarów grawimetrycznych stanowiącą system grawimetrycznego odniesienia polskich stacji permanentnych GNSS i poligonów geodynamicznych. Dolnośląska część tego systemu składa się z pięciu punktów położonych w miejscowościach: Wrocław, Kłodzko, Janowice Wielkie, Lubiąż i Świebodzice. W niniejszej pracy szczegółowo omówiono położenie punktów Wrocław, Kłodzko, Janowice i Lubiąż, sposób ich stabilizacji oraz wyniki pierwszych pomiarów zrealizowanych na tych punktach.

EN

In years 2006–2007, at the area of Poland there were established a network of the absolute gravity measurements points for definition gravity reference system of the Polish Permanent GNSS network and geodynamic networks. Lower Silesian part of the system consist of five points situated in places: Wroc"aw, K"odzko, Janowice Wielkie, Lubi#$ i &wiebodzice. The paper contain detailed description of location of the points Wroc"aw, K"odzko, Janowice and Lubi#$, methods of monumentation and first results of measurements made at the points.

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The feasibility of applying automatic target recognition in trigonometric levelling

Próchniewicz D., Szpunar R., Walo J., Pachuta A.

Reports on Geodesy

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2007

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z. 1/82

267-273

EN

The obtained results of the field experiments fully confirmed the feasibility of applying ATR systems in trigonometric levelling. In the tested span experiment at Józefosław, the value difference of height differences obtained with precise geometric levelling and the mean value of all measurements differed by a mere 2.7 mm, and for midnight measurements - it did not exceed 1 mm. The measurements made in the Pieniny Range were also successful in the case of observation compatibility and limiting the impact of atmospheric refraction on measurement results. Unfortunately, the comparison of the obtained height differences with those of 5 years ago showed considerable discrepancies stemming from benchmark subsiding rather than technological accuracy of trigonometric levelling. To verify this thesis it is planned to repeat trigonometric measurements on the testing ground in the Pieniny and to carry out control measurements by means of precise geometric levelling. Summing up, one can note that the use of tacheometers along with ATR enables to automate measurements and related quasi-continuous observations. These traits enable moreover: - to increase the number of observations, and what follows, increase accuracy and reliability of the zenithal length determined, - to average measurements made over a long period, which enables to undermine the influence of atmospheric refraction on the value of height difference measured, - to make observations in different atmospheric conditions, including nighttime when the atmosphere is stable, - to eliminate personal errors of the observer, - to analyze conducted observations in real time.

15

Scientific expeditions to Svalbard, organized by the Faculty of Geodesy and Cartography, the Warsaw University of Technology (WUT)

Pachuta A., Walo J., Adamek A., Woźniak M., Rajner M., Węzka K., Próchniewicz D

Reports on Geodesy

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2007

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z. 1/82

243-250

16

Displacement monitoring of engineering objects using GPS-RTK technique

Szpunar R., Walo J.

Reports on Geodesy

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2007

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z. 2/83

83-87

EN

Determination of the geometrical characteristic of engineering objects is necessary to thier safa exploitation. Modern terrestrial and satellite measuring techniques make possible the permanent monitoring of the objects. The techniques make also possible Poster presents a concepr how to take advantage of kinematics satellite GPS-RTK measurements and FIR filtres to determine of few millimetres displacement.

17

Control network analysis of the dam "Wióry"

Walo J., Szpunar R., Woźniak M.

Reports on Geodesy

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2007

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z. 1/82

376-380

EN

The obtained results of the test measurements in the control network of the dam Wióry show that combined usage of length measurements and GPS observations enables to obtain high accuracy and reliability in defining point coordinates. The real determination accuracy of checkpoint displacements in this type of networks is at the level of (plus minus) 2-3mm. However, it should be added that in small networks covering an area up to 1 km in radius, classical measurements (most of all, length measurements) enable to obtain higher accuracies in determining point coordinates, obviously on condition that the net structure is well-designed and length measurement is possible. Having analyzed the obtained results, one can also formulate the following conclusions: - the assumed structure of a modified test network shows effective accuracy both for EDM measurements and GPS observations, - satellite measurements enable combined and direct observation of points between which there is no sight line. It is especially important in the case of reference points which are usually located around the monitored object, and it is rarely possible to link them by means of classical measurements; - GPS measurements make it possible to check the monitored network independently, at least limiting the incidence of major and systematic errors in processing the results and defining displacement values; so GPS observations may, in the case of small control networks, be treated as control measurements made periodically (e.g. every year); - accuracy assessment made for TDA5005 tachymeter observations even in the case of considerable target inclinations, made by means of standard reflectors, attested reflexive foil and CCR fulfills monitoring requirements of specific point (targets), enabling to obtain an accuracy of the (plus minus) 0.5 mm range in relation to reference points; - linear measurements in the test network of Wiory, made by means of a TDA5005 tachymeter and high precision reflectors can be accomplished within 2-3 days.

18

Analysis of short-terms height changes of the Hans Glacier using quasi-continuous GPS observations

Walo J., Adamek A., Puczko D.

Reports on Geodesy

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2007

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z. 1/82

367-373

EN

The analysis of the measurement results exemplifies very valuable information about the glacier behavior which glaciologists need to understand phenomena occurring on the glacier in different seasons. Beside the experiences collected during this experiment it will be the background to design similar investigations from survey technology and methodology point of view. Basing on these results and experiment analysis we can draw some conclusions: - In the period of the experiment the glacier surface felt down as much as 2 meters. This is the natural tendency and consequences of flowing down the glacier to the fiord and his ablation. - In the figures we could notice wavy nature of the phenomenon of the glacier surface which probably is connected with topography of the fiord bottom, ocean tides affected on the glacier front and some processes connected with the ablation water delivery to the glacier bed. This problem requires a detailed study based on environmental data. - The results of determined heights were periodically disrupted by atmospheric conditions (snowing, wind). - The GPS data used to follow the vertical velocity of the glacier surface let us to monitor the glacier with height accuracy. Also the automation of the survey and post-processing is possible. - There are some disadvantages of using this monitoring technology in surveys: one point of observations, influence of atmospheric conditions on the results of surveys, periodically hard access to equipment and not good enough way of installation of the satellite antenna on the glacier (ablation pole).

19

Testing of gravimetric quasigeoid by astronomical measurements

Mojzes M., Husar L., Janak J., Papco J., Czarnecki K., Barlik M., Bogusz J., Walo J.

Reports on Geodesy

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2006

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z. 4/79

203-211

EN

The current determination of quasigeoid is largely based on gravimetric observations, which in general do not cover areas equally. That causes decreasing in quality of quasigeoid determination in those areas that are sparsely covered (surveyed) by gravimetric measurements. This situation was occurred on territory of the Slovak Republic in the Tatra Mountains area where gravimetric observations were performed only in some valleys and crests and from Polish side were only applied average values of Bouguer gravity anomalies with a 5' x 7.5' grid spacing (10 km x 10 km) which were transformed to average free-air gravity anomalies. To testing precision of the determined gravimetric quasigeoid it's desirable to use independent method such as astronomical method. Essentially is concerned with comparison astronomical and gravimetric of vertical deflections in the given region and with modelling of the differences between astronomical and gravimetric vertical deflections.

20

Monitoring of Hans Glacier movement dynamics (Hornsund Sw Spitsbergen, Svalbard)

Walo J., Puczko D., Adamek A., Węzka K., Malinowski Z., Rajner M.

Reports on Geodesy

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2006

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z. 1/76

173-179

EN

Fast and exact GPS measurements are independent from weather and season of the year. For achieving reliable results, survey should be conducted at least once a month and at least twice a month in summer season (June-September). GPS RTK is suggested for pole movement determination. In case of real-time corrections limited availability (i.e. screening by mountains) using Rapid Static is a good choice. To minimize multipath error antenna should be placed at least 0,5m eccentric to pole and at 1 m height. Ablation pole movement vectors of Hans glacier indicate few relations. Most important feature is speed being about 10 times greater in foremost zone of glacier than in lateral parties of glacier. Measurements of lateral profile indicate that, accordingly to expectations, surface speed of glacier is greater in middle axis comparing to the edges or glacier.