This article describes an experiment carried out with the GNSS RTK method to combine GPS and GLONASS measurements in obstructed and unobstructed sites. This study investigates the RTK achievable ...accuracy and repeatability under different satellite constellations and site conditions in Samatya (coastal area), Istanbul, Turkey. The RTK (GPS and GPS/GLONASS) measurement techniques are described and compared in terms of productivity and precision. Surveyed area, control and test points as well as the impact area of trees where the precision decreases are visualised using Autodesk LandXplorer Studio ProfessionalTM Software. These obtained results indicate that integrating RTK GPS system with GLONASS is favoured for surveying applications.
The purpose of this study is to evaluate the repeatability of RTK GPS method under varying satellite configurations by using different reference points. Furthermore, we conducted one way Analysis of ...Variance (ANOVA), which is a powerful tool for comparing the variability of related types of measurements. Multi-reference station is a well-known approach in RTK GPS. Using multi-reference points is an effective way to achieve consistent accuracy in the whole net by making errors less distance dependent on the reference stations. It is possible to achieve high reliability and availability by using multi-reference stations. If one station goes down or starts to provide suspicious values, it is possible to compensate the situation with other stations, while this is not possible when a single reference station fails. Here we present ANOVA which is an effective method to check the quality of corrections generated from each reference station.
Zemljiškokatastrski prikaz (ZKP) je grafični prikaz vseh parcel in parcelnih številk v Sloveniji. Po opredelitvi je to slika oblike in medsebojne lege parcel. Položajna natančnost ZKP je zelo ...različna in je na nekaterih območjih celo zelo slaba. Težave s položajno natančnostjo odpravlja zemljiškokatastrski načrt (ZKN), ki je izdelan na podlagi kakovostnih podatkov, pridobljenih v postopkih vzdrževanja zemljiškega katastra. V prispevku so predstavljeni viri podatkov za izdelavo ZKN, metoda izdelave ZKN za posamezne tipe podatkovnih virov, kakovost izdelka, zagotovljen način vzdrževanja ZKN, praktična dostopnost in možnost širše uporabe ZKN ; The Land Cadastre Representation (ZKP) is a graphic representation of all parcels and parcel numbers in Slovenia. By definition, this is the image of the shape and position of the parcels. The positional precision of the ZKP is highly variable, in some areas even very poor. The Land Cadastre Plan (ZKN) is made on the basis of high quality data obtained in the processes of maintaining the land cadastre and solves the problems with positional precision. This paper presents the data sources that produce the ZKN, the ZKN's method for producing various types of data sources, the quality of the product, the way of maintaining the ZKN, as well as the practical accessibility and possibility of wider use of the ZKN.
For the most common geodetic tasks such as surveying, staking out and monitoring, GNSS RTK method has in many cases been limited by its measuring quality. Combining laser system with GNSS RTK system ...enables the increase of vertical accuracy of measurement to a millimetre level. Testing the above mentioned systems for height determination will be presented in this paper. Since December 2008 CROatian POsitioning System (CROPOS) has been operational. GPS RTK system combined with laser system has been tested with CROPOS service, because more and more users are using this system in every day geodetic tasks. Testing the vertical accuracy of measuring modes has been done on the calibration baseline of the Faculty of Geodesy in Zagreb. Heights were determined by four different measuring modes; GPS RTK method in combination with laser system, GPS RTK method in combination with laser system linked with CROPOS service (VPPS - Very Precise Positioning Service), GPS RTK method and GPS RTK method linked with CROPOS service (VPPS). The authors of the paper will try to examine whether it is possible to achieve higher accuracy of vertical component when GPS RTK system is combined with laser system. Finally, the advantages, possible disadvantages, and vertical quality comparison of all measuring modes will be shown in this paper
Full text
Available for:
IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UL, UM, UPUK
SI: Geodetske metode so eden od možnih načinov za ugotavljanje stabilnosti geotehničnih objektov. Spremljanje premikov geotehničnih objektov je zaradi velikosti objektov in pričakovanih premikov ...nekoliko specifično. Pričakovana velikost premikov določa potrebno natančnost določitve premikov, velikost objekta pa določa metodo geodetske izmere. V osnovi izbiramo med terestričnimi metodami in metodami GNSS (globalni navigacijski satelitski sistem. Ker za izvajanje geotehničnih meritev ni ustrezne zakonske podlage, predstavljamo posebnosti posameznih metod in navajamo splošna priporočila za izvedbo geodetskih postopkov pri spremljanju premikov geotehničnih objektov. Priporočila so namenjena projektantom geotehničnih objektov in izvajalcem geodetskih del ter investitorjem, ki jim lahko olajšajo nadzor nad izvajanjem geotehničnih projektov.ENG: Geodetic methods are one of the possible means of determining the stability of geotechnical objects. The determination of the displacements of the geotechnical objects is specific due to the size and the expected displacements. The expected size of the displacement determines the necessary precision of the displacement determination, whereas the size of the object determines the method of the geodetic measurement. We choose either the terrestrical or the GNSS methods. There is no relevant legal framework for geotechnical measurements. For this reason,we present the characteristics of the single methods and suggest general recommendations regarding the implementation of the geodetic procedures when monitoring the displacements of the geotechnical objects. The recommendations are intended for geotechnical engineers planning the geotechnical objects and the operators of geodetic measurements and investors. The recommendations the facilitate supervision of the geotechnical projects.
Presojanje nevarnosti in ogroženosti zaradi delovanja drobirskih tokov ne temelji samo na domnevah o izvornih območjih in magnitudah možnih drobirskih tokov ter njihovih reoloških lastnostih, temveč ...tudi na napovedi njihovega dosega. Glede na zajem topografijepovršine pobočja, po katerem teče pobočni drobirski tok, ali zajem oblike hudourniške struge, po kateri se premika drobirski tok, predstavljamo rezultate dvodimenzijskega matematičnega modeliranja možnih drobirskih tokov na izbranih hudourniških vršajih v dolini Save Dolinke v odvisnosti od velikosti računske mreže (5 x 5 m in 15 x 15 m), generirane iz digitalnega modela višin 5 m (DMV 5). Z vidika numeričnega modeliranja drobirskih tokov smo pokazali, da je treba modelirati tudi zgradbe, ki jih DMV 5 ne obsega, sajimajo velik vpliv na tokovno polje v bližini. Pristop, pri katerem so se zgradbe v numerični računski mreži upoštevale z vpeljavo blokiranih (suhih) celic, se je pokazal kot boljša rešitev od večanja koeficienta hrapavosti v teh celicah, da bi upoštevali motnje v toku, ki jih povzročajo zgradbe. Preverili smo tudiuporabnost digitalnega modela reliefa DMV 12,5 in iz njega generirali numerično mrežo 12,5 x 12,5 m. Na primeru hudourniškega vršaja Trebiže smo ugotovili, da je DMV 12,5 lahko bolj geomorfološkoreprezentativen kot DMV 5. Naslednji korak pri modeliranju naravnih nevarnosti, kot so drobirski tokovi, bo uporaba bolj natančne računske mreže (recimo 1 x 1 m), generirane iz lidarskih posnetkovpovršja.
This paper explores the problems caused by human impact with settlements and infrastructure in the surface water bodies, especially in potential flood plans. Moreover, the principles and obligations ...of the EU Flood Directive (2007/60/EC), which supplements the Water Frame Directive, are discussed. The principles and obligations of this directive have been introduced in Slovenia by local legislation: Decree on conditions and limitations for constructions and activities on flood risk areas (OG RS, No. 89/2008) and Rules on methodology to define flood risk areas and erosion areas connected to floods and classification of plots into risk classes (OG RS, No. 60/2007). Some features and obligations of state-ofthe-art hydraulic mathematical models for surface water dynamics simulation are described. Several problems encountered in developing the models and simulating problems are described; these involve using temporarily available geodetic data of the river beds and flood plans and some suggestions for improving of the modelling are made.
Zračno lasersko skeniranje, imenovano tudi lidar (light detection and ranging), lahko uporabimo kot samostojno tehniko snemanja ali v kombinaciji z različnimi tipi snemanj (od klasičnih ...fotogrametričnihsnemanj do hiperspektralnih snemanj). Glavna prednost zračnega laserskega skeniranja pred drugimi tehnikami daljinskega zaznavanja je, da detajle na reliefu neposredno izmerimo in jih ne pridobimo z naknadno restitucijo iz stereoparov. V članku bomo prikazali možnosti uporabe zračnega laserskega skeniranja za obnovo podatkov različnih nepremičninskih evidenc v Sloveniji. Možnost uporabezračnega laserskega skeniranja pri ažuriranju katastra stavb in zemljiškega katastra še ni opredeljena v zakonskih in podzakonskih predpisih, ki te evidence opredeljujejo. Zato bomo v članku opredelili minimalne pogoje, na podlagi katerih se bomo lahkoodločili, ali bomo zračno lasersko skeniranje lahko uporabili v praksi: potrebna natančnost, višina leta in gostota laserskih točk na enoto površine. Aerial laser scanning, also called lidar (light detection and ranging), can be used as a stand-alone acquisitiontechnique or in combination with other types of aerial surveys (from classic photogrammetric to hyperspectral). The basic advantage of lidar in comparison with other remote sensing techniques is that the details on the relief are directly measured rather than acquiredwith additional stereo-restitution. In this paper, we will describe the possibilities of lidar being involved in data acquisition for different real-estate databases in Slovenia. The possibility of applying lidar to the building cadastre and the land cadastre measurements has not been yet defined in the legislation definingthese databases. Therefore, we will define the minimal conditions that will enable us to decide if lidar can be applied for those databases in practice: required accuracy, flying height and number of points per m2.
V prispevku je opisan postopek izvedbe nadzora kakovosti podatkov zemljiškega katastra v novem državnem koordinatnem sistemu D96/TM, ki ga izvaja Geodetska uprava Republike Slovenije in obsega ...kontrolo položajne natančnosti zemljiškokatastrskih točk. Podrobneje je predstavljen tehnični del postopka nadzora kakovosti, ki obsega mersko in programsko opremo, metode izmere, obdelavo podatkov in vrednotenje rezultatov kontrole. Predstavljeni so rezultati izvedenega nadzora v letu 2008 in nekateri primeri napak, ki se pojavljajo pri sami geodetski izmeri. The procedure of the supervision of the Land Cadastre quality data in the new national coordinate system D96/TM, which is performed by the Surveying and Mapping Authority of the Republic of Slovenia and consists of horizontal accuracy control of land cadastre points, is described in this article. The technical part of data quality supervision procedure, which includes the measurement equipment and software, measurements methods, data analysis and evaluation of results, is presented in detail. The results of the of the 2008 data quality supervision procedure are described; some mistakes, which are made by geodetic measurements, are also presented.
The optimization of geodetic measurements is described in this paper. It is a part of the geodetic survey design procedure and gives the answers to important questions, which we would normally deal ...with at the end, when analysing the quality of the results obtained. The basic criteria for optimization of geodetic measurements are described, such as accurracy, reliability and costs of the geodetic survey, according to which the optimisation is performed. At the end three examples of the second order design ofgeodetic measurements are presented.
