Although a dynamic or semi-dynamic datum has been adopted in some countries, it remains a challenge if a long-term stable datum is to be established in a tectonic active area. This study presents an approach to realistically reflect the time dependent behaviors of ground reference points while maintaining the long-term stability of a datum. An adaptive approach coupled with the Euler motion model is

Applicability of SLAM (simultaneous localization and mapping) technology for mine surveys and subsequent 3D modelling of post-extracted surfaces is assessed. The resulting surface geometry is validated via terrestrial laser scanner (TLS) acquired reference data. Typical discrepancies remained within 2 and 5 cm in horizontal and vertical directions, respectively. Discrepancies between TLS, SLAM-enabled

Complexity of urban construction and land use is increasing which cannot be represented adequately by 2D systems. The successful construction of a Spatial Information Model of 3D Real Estate (SIM-3RE) is valuable to achieving a refined administration of 3D space and property-rights of urban real estate in China. In this paper, the Nanjing Gulou Central Business District was selected as an experimental

A high-resolution gravimetric geoid model for the Kingdom of Saudi Arabia area was determined. A data set of 459,848 land gravity, 80,632 shipborne marine gravity data, DTU17 altimetry gravity model, and XGM2019e global geopotential model. The computation strategy followed for modelling of the gravimetric geoid is based on the Remove-Compute-Restore with Residual Terrain Model reduction and the 1D-

The NUVEL1-A is one of the old and popular plate tectonic models. While the NUVEL1-A is a geological-based model, recently a model has been proposed (GSRM2.1 model) which is based on the results of space geodetic techniques. In this work, we investigate the consistency of these models with the VLBI and SLR results in Europe. Direction and magnitude of the horizontal motion from NUVEL-1A and GSRM2.1

Numerous studies for improving gravity field determination from future gravity missions beyond the GRACE/GRACE-FO missions have been proposed during the last decade. In this contribution, full-scale simulated observations of four satellite missions, namely Bender-, Cartwheel-, Helix- and Pendulum-type, in addition to GRACE-FO as a reference mission will be used to retrieve the total water storage over

In some cases, tests for outliers and robust methods based on the Least Square Estimation (LSE) fail to detect and isolate outliers. LSE 'smears the effect' of an outlier on all estimates of the residuals, the unknowns, and the a posteriori variance of unit weight. Therefore as bias goes to infinity, the Influence Function (IF) also goes to infinity. This study aims to investigate the effect of an

During designing a railway track, the accumulated errors in the transmission of coordinates affect the construction cost, change the conditions for designing tracks and the value of operating costs. If the grade of the track comes closer to the limiting grade, more accuracy is required to draw up the survey plan and terrain profile, and the more often geodetic control points are necessary. It is indicated

Global Navigation Satellite System Reflectometry (GNSS-R) can be used to measure sea level heights based on reflected signals recorded as oscillations in signal-to-noise ratio (SNR) data. This study utilizes the SNR data from an existing MERS, located in Erdemli, Mersin on the Mediterranean coast of Turkey over a one-year time period. The dominant multipath frequency in the SNR data is derived with

The National Geodetic Survey began publishing a series of experimental geoid (xGEOID) models annually since 2014. The latest experimental model is xGEOID20. The San Joaquin Experimental Range (SJER) in Fresno County, California is surveyed using Static GPS and precise levelling and a local geoid (SJER Geoid) is created. In this study, SJER Geoid is compared against xGEOID20A&B models and the results

The reliability and robustness of positioning systems in urban and suburban environments are intrinsic. This is obvious following the continuous increase of Intelligent Transportation Systems (ITS) applications in such challenging environments. Global Navigation Satellite Systems (GNSS) represent the primary positioning technique used for navigation purposes in these applications, which can be satisfying

When the regression coefficient of independent variable has both global stationarity and spatio-temporal non-stationarity properties, the deformation model based on the geographically and temporally weighted regression (GTWR) will no longer be applicable. In order to resolve this problem, we propose an improved method to establish the spatio-temporal deformation model using mixed geographically and

In this contribution, two gravimetric geoid models for Egypt; EGY-LGM2019 and EGY-FGM2019 are developed using the least-squares collocation and the Fast-Fourier Transformation methods, applying Remove-Restore procedure. Different datasets are used in terms of gravity anomalies obtained from GOCE-based SPW-R5 and EGM2008 models, and from 1015 terrestrial gravity stations. Two gravimetric geoid models

Namibia currently undergoes a rapid process of urbanisation of 4% annually, visible through an exponential informal settlement growth. Alternative measurement methods in cadastral mapping could secure land tenure in these settlements and fasten land registration. This article investigates the performance of five alternative measurement methods within the Flexible Land Tenure System (FLTS): orthophoto-based

GNSS signals are affected when solar activity causes sudden variations in the density of the ionosphere. Few studies concentrate on positioning performance of IGS stations using different GNSS receivers under different geomagnetic storm conditions. This paper for the first time presents IF and UC PPP positioning performance of stations with different receivers during the quiet, moderate, intense, and

It is of vital importance to search for an objective quality metric which can provide insights into the geometric strength of the underlying adjustment model. The Minimal Detectable Bias (MDB) measure has been extensively used in geodesy and photogrammetry. However, MDB is a hypothetical quality measure. To this end, the Maximum Tolerable Bias (MTB) metric is introduced in this contribution. The definition

In this work, the principal aim is to evaluate some recent GGMs on the Gulf of Guinea region using shipborne free-air gravity data. Two types of GGMs are evaluated in this study: combined models (EGM2008, EIGEN-6C4, GECO, SGG-UGM-1, GOCO05C and XGM2016) and satellite-only models (DIR_R5, ITU_GGC16, SPW_R5, TIM_R5, GGM05G and NULP_02S). The comparisons between these GGMs and the preliminary filtered

Through a series of experiments of dynamic deformation and destruction under time series loading on an indoor real model bridge, Ground-based real-aperture radar interferometry (GB-InRAR) discovered that before the structure of the bridge was damaged, its amplitude and acceleration increased with the increase of load; After its structure was damaged or cracked, such dynamic characteristics as natural

This contribution provides a comparison between the Gaussian and decorrelation filters as derived from GRACE products (RL05) estimated by the official GRACE Science Data System centres (GFZ, CSR and JPL) as well as the ITSG-GRACE2016 solutions over Egypt. The outcome of this study will help in finding out which of these centres provides improved temporal gravity solutions as well as the most promising

In geodesy, in addition to observation information, there are also parameters additional useful information. Making full use of them can make up for the lack of observation information and form effective constraints on unknown parameters. In order to make the adjustment results unique and stable, we build a function model to solve inequality constraints, and based on the linear complementarity theory

The partial errors-in-variables (PEIV) model is a structured form of errors-in-variables (EIV) model reformulated by collecting all the independent random elements of the coefficient matrix. When some reliable inequality constraints are taken into account, the adjustment results of inequality constrained PEIV (ICPEIV) model are probably improved. In this contribution, we first present the optimality

In Turkey, calculation of the factors affecting the value of the condominium units of a building via 2D architectural project data leads to problems. One of the biggest problem is the land share calculation. The aim of this study was to establish a mechanism by which the properties of the factors affecting the value can be determined mathematically and to arrive at a value-based land share. For this

The goal of this paper is to compare academic and online GNSS processing services for CORS-TR. To determine whether differences in the coordinate components were statistically significant, statistical significance test and 3D coordinate transformation were applied. Furthermore, local coordinates analysed to show jumps that occurred to seismic events. While there are significant differences only in

In the absence of enough gauging stations for monitoring lake water level, three (3) methods are presented in this research: (1) Synthetic Aperture Radar (SAR) backscatter from discrete object; (2) Global Navigation Satellite System (GNSS) levelling; and (3) satellite altimetry. The results showed that the Laguna Lake water level is not homogeneous but instead varies at different locations. The GNSS

The major objective of this research is to investigate the progress of citizen participation in cadastral surveying and to consider ways on how to introduce gamification tools for further improvement. A brief literature review is presented in the areas of the Sustainable Development Agenda 2030 related to land administration and citizen engagement, e-government and citizen participation and gamification

Imperial hegemony established by the Habsburg Monarchy relied upon proper mapping during its conquests. The need for the development of geodesy and establishing reference frames was important. Until the end of the First World War, Vojvodina belonged to the Austrian-Hungarian Empire, so all of its surveys were carried out as part of many organized land surveys in the Monarchy. Today, more than 100 years

The search procedure, as a part of the Modified Ambiguity Function Approach (MAFA), is conducted in the coordinate space. The main advantage of searching for a fixed solution in the coordinate domain, instead of in the ambiguity domain, is the constant search space dimension, which amounts to three. In contrast, an ambiguity space dimension can presently achieve over twenty when the positioning is

The advent of the Gravity Recovery and Climate Experiment (GRACE) and Gravity field and steady-state Ocean Circulation Exploration (GOCE) has changed the global contribution in the determination of high-accuracy global geopotential models (GGMs). In this paper, a spectral expansion method is used to determine the combined GGMs, using the high-resolution EGM2008 model and residual terrain model (RTM)

This paper aims to design a method of multi-source data fusion in multi-target collaborative navigation. First, the respective features of GPS/INS/RS/MO data in the navigation process are clarified. Then a multi-source data fusion method is designed including GPS/INS data fusion with adaptive Kalman filter, RS/MO data fusion with ranging table matching of observation targets, and joint adjustment with

Fit-for-purpose land administration (FFPLA) concept is widely applied in the emerging land administration systems (LASs). This paper aims to contribute to the development of evaluation of the spatial aspect of FFPLA. A review of evaluation models for LASs is made in relation with rationale of FFPLA to identify gaps related to evaluation of a FFPLA and to build up milestones and measurement criteria

The goal of this paper is to evaluate the outlier identification performance of iterative Data Snooping (IDS) and L1-norm in levelling networks by considering the redundancy of the network, number and size of the outliers. For this purpose, several Monte-Carlo experiments were conducted into three different levelling networks configurations. In addition, a new way to compare the results of IDS based

Since 2006, several different groups have computed geoid and/or quasigeoid (quasi/geoid) models for the Auvergne test area in central France using various approaches. In this contribution, we compute and compare quasigeoid models for Auvergne using Curtin University of Technology’s and the Swedish Royal Institute of Technology’s approaches. These approaches differ in many ways, such as their treatment

The integration of survey-grade Global Navigation Satellite Systems (GNSS) with photogrammetric measurement studies conducted with an aircraft has the potential to meet the need for the use of ground control points (GCP). In photogrammetric studies, there are different GNSS techniques to provide the precise positioning of the aircraft. The precise point positioning (PPP) technique has become an alternative

The performance of precise point positioning (PPP) mainly depends on satellite orbit and clock accuracy. Ultra-rapid and rapid orbit/clock products have been creating by analysis centres (ACs) for time-critical applications. In this paper, GPS-, GLONASS-, Galileo-, and BeiDou (BDS-2)-only PPP with ultra-rapid and rapid products from seven ACs (i.e. CODE, ESA, IGS, GFZ, JPL, NRCan, and WUHAN) are investigated

The importance of geospatial data has rendered it to be used in decision-making in both public and private sectors. The purpose of this study was to employ Semantic Web Technology (SWT) for the problems of Web Service Composition (WSC) in the context of Spatial Data Infrastructures (SDI). Some of these problems are identifying the workflow sequence and the user goal, discovering services according

Cadastre in Turkey is executed as two-dimensional (2D) and parcel-based. The third dimension (3D) on land and real estate is shown in 2D on the map with permanent rights. The use of underground spaces cannot be registered. There are various problems in the registration and mapping of real estates that are under or above these excluded places. The research was motivated by some problems that have taken

In this study, a comprehensive assessment of four-satellite Quasi-Zenith Satellite System (QZSS) constellation is conducted, including the quality of navigation signals, the accuracy of broadcast ephemeris, the availability of satellite constellation, the performance of single point positioning (SPP), the interoperability with GPS, and the inter-system bias (ISB) against GPS. Regarding the signal quality

This paper presents a 3D cadastral data model for buildings. A review of the relevant research shows that a common concept in the 3D cadastre domain is using the legal building unit, i.e. real property unit, as the core modelling unit. Alternatively, this study proposes using indoor space as a core modelling unit. The main reason is to enable the efficient integration of cadastral data with the data

Multi-constellation GNSS precise point positioning (PPP) typically uses the extended Kalman filter (EKF) for kinematic applications. Unfortunately, the obtained positioning accuracy in this approach is prone to errors caused by measurement outliers and the system’s dynamic model. An adaptive robust Kalman filter (RKF) was recently developed to mitigate these errors. However, RKF uses empirical values

Navigation in harsh environments mostly encounters many problems such as signal blocking due to a variety of obstacles around the receiver. Vectorised receiver has an architecture in which the channels can share the information. As a result, the strong channels aid the blocked one to reacquire the signal immediately after returning. However, if the output of a channel is undesirable, it may disrupt

A detailed discussion of the adjustment problems used to combine GNSS/levelling/gravity network data is provided in this paper. The two primary problems inherent to heterogeneous data networks, namely, parametric models that describe the datums and systematic distortions among the available data sets and stochastic models that describe the observational residuals, are described. For parametric models

If both the coefficient matrix and the observation vector are affected by noise, a total least-squares algorithm should be applied to obtain the solution. However, if they are also contaminated by outliers, the solution of the algorithm will seriously deviate from the true values. Therefore, the effect of outliers needs to be eliminated. For this purpose, the robust estimation is introduced into the

Determination of Cartesian coordinates of building can be performed using various surveying methods. One of these methods is real-time measurement in RTN GNSS mode. Therefore, tests were carried out that led to surveying contractors being presented with an alternative of using RTN GNSS surveys to determine the location of a building with high reliability and accuracy. This solution involves the harmonisation

Regular as-built surveys have become a necessary input for building information modelling. Such large-scale 3D data capturing can be conducted effectively by combining structure-from-motion and unmanned aerial vehicles (UAV). Using a RTK-GNSS equipped UAV, 22 repeated weekly campaigns were conducted at two altitudes in various conditions. The photogrammetric approach yielded 3D models, which were compared

The first production-oriented strapdown airborne gravimetry in Turkey was carried out during fall 2019 over the Turkish Lake District. Comparisons at the large amounts of crossover points yield RMSE values below 1 mGal level, and the external comparison with the latest high-resolution global geopotential model (GGM) shows a mean bias of around 1.1 mGal where the largest deviations are observed on the

Forecasting future sea levels is of great importance in terms of the conservation of coastal areas, monitoring and forecasting coastal ecosystems, and the maintenance and planning of coastal structures. In addition, highly accurate sea level forecasts allow adequate water management policies and coastal infrastructures to be developed. Today, many methods, such as harmonic analyses, artificial neural

A constrained extended Kalman filter (CEKF) based on least-squares variance component estimation (LS-VCE) is generally developed by condition equations since the proper prediction of dispersion matrices is one of the main bottlenecks in the KF algorithms. Here we investigate four problems which have not been simultaneously considered yet. These problems are examination of non-linearty of dynamic model

Before now, the various studies that have been undertaken to investigate the positioning performance of GNSS Online Services have been limited with regard to both time and number of sessions. Within the scope of this study, the accuracy of the velocity models estimated by APPS and AUSPOS are analysed using a wider period. Local ISKI CORS Network stations are used as the subject. To generate true values

Before now, the various studies that have been undertaken to investigate the positioning performance of GNSS Online Services have been limited with regard to both time and number of sessions. Within the scope of this study, the accuracy of the velocity models estimated by APPS and AUSPOS are analysed using a wider period. Local ISKI CORS Network stations are used as the subject. To generate true values

A Lambert Conformal Conic (LCC) projection with two true-scale parallels of latitudes ϕl and ϕu can be recast in a LCC projection with one standard parallel of latitude ϕ0 and scale k0 , having the practical advantage that the same type of definition can be used for the two conformal projections universally used: LCC and Transverse Mercator (TM). While equations giving ϕ0 and k0 in terms ϕl and ϕu

This paper adapts and discusses the information criterion (IC) approach for the validation of baseline GNSS observation models in the context of outliers. Three IC methods are compared with the conventional procedure of iterative data snooping (IDS). To verify the reliability of the two considered approaches, several scenarios differing in: the magnitude and number of outliers, and the interval between

The paper describes the model for coordinate transformation between ETRS89 and old reference system in the Republic of Srpska. The Helmert’s parameters were estimated, based on a set of 1741 points. The average magnitude of residuals was 0.3 m per coordinate and they were homogeneous at the local level. The basic model was complemented by a corrections grid that uses bilinear interpolation. The accuracy

Land consolidation project has many stages. Land reallocation is the most considerable stage in which many factors play a role and forms the basis of this project. In this study, a new optimisation-based reallocation model has been developed to realise block reallocation by evaluating the requests of landowners. The reallocation according to the developed method also reset the block spaces automatically

The main purpose of this study is to propose an interoperable land valuation data model for residential properties as an extension of the national geographic data infrastructure (GDI) and to make mass valuation process applicable with the use of machine learning approach. As an example, random forest (RF) ensemble algorithm was implemented in Pendik district of Istanbul to evaluate the prediction performance

To develop a high-accuracy method for predicting SCB based on the analysis of the shortcomings of the wavelet neural network (WNN) model, an improved WNN model to predict SCB is proposed herein. The activation function of the WNN is constructed by combining the advantages of Shannon and Gauss ‘window’ functions to improve the WNN. Finally, the improved WNN model is used to predict SCB. The results

The concepts of three-dimensional cadastre (3D) and property ownership led to increased interest in land use management and research towards the end of the 90s. Within the scope of these studies, international standards and definitions have been realised. In Turkey, there are some academic studies available. However, there are not many studies conducted on an institutional basis. Turkey cadastre carried

Turkey has produced cadastral data using different methods until today. Therefore, not all the data are the same standard in quality. Three different methods (correction, digitisation and updating) have been applying for update. Choosing the right method will save significant time and cost. Also, surveying the fixed boundaries will give the most accurate results. However, this is not always possible

How to accurately estimate the probability integral parameters based on the measured data has always been a difficult point in the application of the probability integral method. This paper introduced FWA into the solution of the probability integral method for the first time. Based on the analysis of strengths and weaknesses of FWA, IFWA (improved fireworks algorithm) was proposed. Then, the IFWA-based

The cycle slip detection and repair are crucial steps in the preprocessing of GNSS carrier phase observation. Currently, however, there are few cycle slip detection and repair methods that can meet the data processing needs for diverse situations. To solve this problem, a highly adaptable cycle slip detection and repair method is proposed. First, a cycle slip detection equation is established using

The existing filtering methods for airborne LiDAR point cloud have low accuracy. An adaptive filtering algorithm is proposed which is improved based on multilevel resolution algorithm. First double index structure of Octree and KDtree is established. Then the initial reference surface is constructed by ground seed points. According to the slope fluctuation situation, the grid resolution of the ground