Autor: Walo, J. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Analysis of short-terms height changes of the Hans Glacier using quasi-continuous GPS observations
Autorzy:: Walo, J.
Adamek, A.
Puczko, D.
Powiązania:: https://bibliotekanauki.pl/articles/225003.pdf
Data publikacji:: 2007
Wydawca:: Politechnika Warszawska. Wydział Geodezji i Kartografii
Tematy:: GPS
satelita GPS
system pozycjonowania obiektów
lodowiec Hans
wysokośc lodowca
pomiary geodezyjne
GPS satellite
Global Positioning System
Hans Glacier
glacier height
engineering surveying
Opis:: 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).
Źródło:: Reports on Geodesy; 2007, z. 1/82; 367-373
0867-3179
Pojawia się w:: Reports on Geodesy
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Control network analysis of the dam "Wióry"
Autorzy:: Walo, J.
Szpunar, R.
Woźniak, M.
Powiązania:: https://bibliotekanauki.pl/articles/225005.pdf
Data publikacji:: 2007
Wydawca:: Politechnika Warszawska. Wydział Geodezji i Kartografii
Tematy:: zapora ziemna
sieć kontrolna
Wióry
pomiary geodezyjne
earth dam
control network
engineering surveying
Opis:: 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.
Źródło:: Reports on Geodesy; 2007, z. 1/82; 376-380
0867-3179
Pojawia się w:: Reports on Geodesy
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: The feasibility of applying automatic target recognition in trigonometric levelling
Autorzy:: Próchniewicz, D.
Szpunar, R.
Walo, J.
Pachuta, A.
Powiązania:: https://bibliotekanauki.pl/articles/225056.pdf
Data publikacji:: 2007
Wydawca:: Politechnika Warszawska. Wydział Geodezji i Kartografii
Tematy:: niwelacja trygonometryczna
niwelacja precyzyjna
tachymetr elektroniczny
pomiary geodezyjne
trigonometric levelling
electronic tacheometer
engineering surveying
Opis:: 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.
Źródło:: Reports on Geodesy; 2007, z. 1/82; 267-273
0867-3179
Pojawia się w:: Reports on Geodesy
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Unified gravimetric reference frame for Polish IGS/EPN stations and geodynamic test fields
Autorzy:: Walo, J.
Olszak, T.
Pachuta, A.
Próchniewicz, D.
Szpunar, R.
Powiązania:: https://bibliotekanauki.pl/articles/225691.pdf
Data publikacji:: 2010
Wydawca:: Politechnika Warszawska. Wydział Geodezji i Kartografii
Tematy:: pomiary geodezyjne
pomiary grawimetryczne
surveys
gravity measurements
Źródło:: Reports on Geodesy; 2010, z. 1/88; 105-113
0867-3179
Pojawia się w:: Reports on Geodesy
Dostawca treści:: Biblioteka Nauki