PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 13

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available Impact analysis of observation coupling on reliability indices in a geodetic network
Nowak E., Odziemczyk W.
Reports on Geodesy and Geoinformatics
|
2018
|
Vol. 106
1--7
EN
An optimally designed geodetic network is characterised by an appropriate level of precision and the lowest possible setup cost. Reliability, translating into the ability to detect blunders in the observations and higher certainty of the obtained point positions, is an important network characteristic. The principal way to provide appropriate network reliability is to acquire a suitably large number of redundant observations. This approach, however, faces limitations resulting from the extra cost. This paper analyses the possibility of providing appropriate reliability parameters for networks with moderate redundancy. A common problem in such cases are dependencies between observations preventing the acquisition of the required reliability index for each of the individual observation. The authors propose a methodology to analyse dependencies between observations aiming to determine the possibility of acquiring the optimal reliability indices for each individual observation or groups of observations. The suggested network structure analysis procedures were illustrated with numerical examples.
2
Content available Control network reliability reconstruction for Zatonie dam
Nowak E., Odziemczyk W.
Reports on Geodesy and Geoinformatics
|
2018
|
Vol. 105
1--5
EN
Absolute horizontal displacements are an important element of dam safety level assessment. Appropriate design of measurement network is a prerequisite for the acquisition of displacement values that meet the reliability requirements. A network of this kind, apart from ensuring the required precision of displacement determination, should be characterised by reliability allowing for elimination of gross errors in the results of geodetic surveys. This study aims to propose a method to improve reliability characteristic of surveying network used for horizontal displacement identification in Zatonie dam. The desired effect (increase in the network’s reliability) is obtained by the authors in two stages. The first stage concerns expansion of the existing network by addition of three free stations. As the obtained effect did not prove to be satisfactory, in the second stage so called observation accuracy harmonisation was carried out, which optimally utilises the reliability potential of the measurement construction. In order to successfully carry out the harmonisation, a modification to the procedure’s algorithm had to be introduced. A design of a network ensuring detection of a gross error in any given observation was obtained as the result of the performed actions.
3
Content available Adjustment of observation accuracy harmonisation parameters in optimising the network’s reliability
Nowak E., Odziemczyk W.
Reports on Geodesy and Geoinformatics
|
2018
|
Vol. 105
53--59
EN
Appropriate precision and low cost are the basic conditions that have to be fulfilled by a project of a geodetic network. Reliability, translating into the ability to detect gross errors in the observations and higher certainty of the obtained point position, is an important network characteristic. The principal way to provide appropriate network reliability is to acquire a suitably large number of redundant observations. Optimisation of the observation accuracy harmonisation procedure allowing for the acquisition of an appropriate level of reliability through modification of the observation a priori standard deviations is the focus of this study. Parameterisation of the accuracy harmonisation is proposed. Furthermore, the influence of the individual parameter operation on the effectiveness of the harmonisation procedure is tested. Based on the results of the tests an optimal set of harmonisation parameters which guarantees the maximal efficiency of the harmonisation algorithm is proposed.
4
Content available remote Ocena przydatności różnych technik pomiaru geometrii układów torowych do opracowania projektów regulacji osi toru
Odziemczyk W., Woźniak M.
Przegląd Komunikacyjny
|
2018
|
R. 73, nr 8
27--32
PL
Do opracowania projektu regulacji osi toru niezbędna jest precyzyjna informacja, dotycząca rzeczywistego przebiegu tej osi. Informacja ta jest zazwyczaj pozyskiwana metodami geodezyjnymi, przy czym najpopularniejszą metodą była do niedawna metoda pomiaru strzałek. Rozwój geodezyjnych technik pomiarowych umożliwia wykorzystanie do tego celu innych metod, w tym: metody tachimetrycznej, metod wykorzystujących obserwacje satelitarne oraz nowatorskich metod pomiarowych, bazujących na wykorzystaniu specjalistycznych, mobilnych zestawów pomiarowych. W celu praktycznego sprawdzenia przydatności nowych metod pozyskiwania danych przestrzennych do opracowywania projektów regulacji osi toru przeprowadzone zostały badania eksperymentalne. Pomiary eksperymentalne wykonano na 3 km odcinku dwutorowym. W ramach przeprowadzonych badań przeanalizowano pomiary z wykorzystaniem następujących metod: tradycyjnej metody pomiaru strzałek, metody tachimetrycznej, metody wykorzystującej technikę GNSS, metody zautomatyzowanej, realizowanej w wariancie jedno- i dwuwózkowym. Wymienione metody porównano pod względem pracochłonności czynności pomiarowych, czasu trwania pomiaru, zakresu uzyskiwanych danych o obiekcie, kosztów sprzętu pomiarowego, niezawodności oraz dokładności procesu pomiarowego. Ponieważ różne metody pomiarowe dostarczają różnych wielkości geometrycznych, porównanie dokładności tych metod pomiarowych oparto na porównaniu wielkości strzałek. Porównanie danych geometrycznych uzyskiwanych za pomocą analizowanych metod pomiarowych pozwoliło na sformułowaniu wniosków, dotyczących przydatności tych metod do wykonywania projektów regulacyjnych.
EN
Precise information of railway tracks geometry is necessary to design alignment project. Geodetic measurements are the most common method of determining this information and sags of arch direct measurement are the traditional and still popular measurement method. Development of geodetic measurements techniques made possible to use another methods such as tacheometry, GNSS, and new methods based on mobile measurement devices. Series of experiments were conducted to set the practical usability of selected modern measurement methods to design track alignment project. The experimental measurements were performed on the 3 km long two-track railway fragment. Following methods were used during the test measurements: sags of arch direct measurement, tacheometry with total station, GNSS, automated methods with the use of a trolley system. Above mentioned measurement methods were compared taking into account time and labour consumption, range of geometric data, measurement equipment cost, reliability and accuracy of surveying procedure. Because of different data types are delivered with various methods, sags of arch were used for comparison of accuracy. Comparison of geometrical data obtained with analysed methods allowed to formulate conclusions concerning practical usability those methods for track alignment project development.
5
Content available Investigation of stability of precise geodetic instruments used in deformation monitoring
Woźniak M., Odziemczyk W.
Reports on Geodesy and Geoinformatics
|
2017
|
Vol. 104
79--90
EN
Monitoring systems using automated electronic total stations are an important element of safety control of many engineering objects. In order to ensure the appropriate credibility of acquired data, it is necessary that instruments (total stations in most of the cases) used for measurements meet requirements of measurement accuracy, as well as the stability of instrument axis system geometry. With regards to the above, it is expedient to conduct quality control of data acquired using electronic total stations in the context of performed measurement procedures. This paper presents results of research conducted at the Faculty of Geodesy and Cartography at Warsaw University of Technology investigating the stability of “basic” error values (collimation, zero location for V circle, inclination), for two types of automatic total stations: TDA 5005 and TCRP 1201+. Research provided also information concerning the influence of temperature changes upon the stability of investigated instrument’s optical parameters. Results are presented in graphical analytic technique. Final conclusions propose methods, which allow avoiding negative results of measuring tool-set geometry changes during conducting precise deformation monitoring measurements.
6
Content available Accuracy analysis of a wireless indoor positioning system using geodetic methods
Wagner P., Woźniak M., Odziemczyk W., Pakuła D.
Reports on Geodesy and Geoinformatics
|
2017
|
Vol. 104
1--19
EN
Ubisense RTLS is one of the Indoor positioning systems using an Ultra Wide Band. AOA and TDOA methods are used as a principle of positioning. The accuracy of positioning depends primarily on the accuracy of determined angles and distance differences. The paper presents the results of accuracy research which includes a theoretical accuracy prediction and a practical test. Theoretical accuracy was calculated for two variants of system components geometry, assuming the parameters declared by the system manufacturer. Total station measurements were taken as a reference during the practical test. The results of the analysis are presented in a graphical form. A sample implementation (MagMaster) developed by Globema is presented in the final part of the paper.
7
Content available Analysis of deformations of the skylight construction at the Main Hall of the Warsaw University of Technology
Odziemczyk W.
Reports on Geodesy and Geoinformatics
|
2014
|
Vol. 97
35--46
EN
The paper presents technology and results of measurements of the steel construction of the skylight of the Main Hall of the Warsaw University of Technology. The new version of the automated measuring system has been used for measurements. This system is based on Leica TCRP1201+ total station and the TCcalc1200 software application, developed by the author, which operates on a laptop computer connected with the total station by the wire. Two test measurements were performed. Each of them consisted of cyclic measurement using the polar method, from one station; points located on the skylight construction, as well as control points located on concrete, bearing poles, were successively measured. Besides geometrical values (such as Hz, V angles and the slope distance D), the changes of temperature and atmospheric pressure, were also recorded. Processed results of measurements contained information concerning the behaviour of the skylight; asymmetry of horizontal displacements with respect to the X axis have been proved. Changes of parameters of the instrument telescope and changes of the instrument orientation were also stated; they were connected with changes of the temperature. The most important results of works have been presented in the form of diagrams.
8
Content available Investigation of practical and theoretical accuracy of wireless indoor positioning system Ubisense
Woźniak M., Odziemczyk W., Nagórski K.
Reports on Geodesy and Geoinformatics
|
2013
|
Vol. 95
36--48
EN
This paper presents the accuracy investigation results and functionality of Ubisense RTLS positioning system. Three kinds of studies were conducted: test of calibration accuracy, analysis of theoretical accuracy of the coordinates determination as well as accuracy measurements in field conditions. Test of calibration accuracy was made with several different geometric constellation of reference points (tag positions). We determined changes of orientation parameters of receivers and disturbance of positioning points coordinates against chosen reference points constellations. Analysis of theoretical accuracy was made for several receivers spatial positions and their orientations. It allowed to indicate favourable and unfavourable measurement area considering accuracy and reliability. Real positioning accuracy of the Ubisense system was determined by comparison with coordinates measured using precise tacheometer TCRP1201+. Results of conducted experiments and accuracy analysis of test measurement were presented in figures and diagrams.
9
Content available Optimisation of distribution of tie points applied to mutual orientation of stations of a survey system, which uses the method of intersections
Odziemczyk W.
Reports on Geodesy
|
2011
|
z. 1/90
349--354
10
Content available Monitoring of the wut grand hall roof in conditions of high temerature changes
Woźniak M., Odziemczyk W.
Reports on Geodesy
|
2009
|
z. 1/86
105-110
EN
Geodetic control measurements of changes in geometry an object should satisfy high accuracy and reliability. New techeometers equipped with Automatic Target Recognition automatically moves the telescope to the prism and supports control point measurements. The accuracy of using an ATR system and the stability of an instrument in precise measurements were present the results of monitoring measurement were controlled in laboratory and field conditions. This paper will present the results of monitoring measurements with a Leica TDA 5005 during the investigations of roof geometry in conditions of high temperature changes.
11
Content available Investigation of short-term roof structure deformations using geodetic methods
Woźniak M., Odziemczyk W., Jastrzębski S., Wojciechowski J.
Reports on Geodesy
|
2008
|
z. 1/84
105-110
EN
The article contains the results of the measurements of the Warsaw University of Technology Main Hall roof deformations under various conditions. These results were obtained autornatically using precise motorized tacheometres TDA5005 and TCRP2002. In this work we compare the vertical components obtained with tacheometric measurements to the results of geometric leveling for chosen control points. The aim of this research was the assessment of the usefulness of the proposed monitoring method to determine structural deformations.
12
Content available The suitability of angle measurements made with steep targets for determining spatial positions of points
Odziemczyk W.
Reports on Geodesy
|
2007
|
z. 1/82
217-223
13
Content available Testing the constancy of the target axis with a change in focusing in precise theodolites and electronic tacheometers
Odziemczyk W.
Reports on Geodesy
|
2007
|
z. 1/82
211-216
EN
The obtained measurement results show that for short targets of a few metres long, position changes of the target axis are considerable and even come close to lc (TC1610). Even in the case of the telescopes of precise T 2002 theodolites geared for close object measurements, target axis vacillations almost amount to 40cc. The course of vertical changes in the target axis vacillations is quite distinctive/typical/unusual/interesting? For all tested instruments the character of these changes was very similar. It is a phenomenon which is difficult to explain in a clear fashion. It should be also noted that the greatest changes take place with short targets up to about 10 m. Vacillations of the target axis above this length are considerably smaller and generally do not exceed 10cc. Although target axis movements expressed in terms of angular units are significant, their influence on accurate location of a point position is slight and does not exceed (especially for the horizontal component) a few hundredths millimeters. In spite of this changes in the target axis should be taken into consideration in designing high precision angular measurements for small objects.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.