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Abstract

In Poland, the cadastre is the basic register which is the source of information on cadastral entities and their property. Therefore, it should constitute a reliable source of information in the scope of establishing the range of law, its nature, but also the subject of its ownership. However, it is necessary to be able to not only check the current information on the legal status and its scope, but also review past statuses or determine the rights that will influence real estate in the future. The cadastre and related rights are changing very dynamically over time, and each state has a very strict reference to the previous state. Therefore, in order to manage real estate in the most effective way, it is necessary to record temporal attributes of cadastre objects.

The main objective of this paper is to define the legal issues related to the possibility of registration at the time of creation or modification of object in the Polish cadastre. This paper includes analyses of both Polish legal regulations and European standards and norms. Moreover, the article presents the results of comparative analyses concerning the data model of cadastre and INSPIRE and Land Administration Domain Model (LADM) data models for the theme cadastral parcel in terms of temporal aspect.

Abstract

Stereo photogrammetry has been used in this study to analyse and detect movements within the Lecture theater of School of Environmental Technology of Federal University of Technology Minna via the use of Kalman filter algorithm. The essential steps for implementation of this method are herein highlighted and results obtained indicate Ins. Mov.s (velocity) ranging from ±0.0000001 m/epoch to ±0.000007 m/epoch with greater movements noticed in the horizontal direction than in the vertical direction of the building. Because the observed movements were insignificant, the building has been classified as stable. However, a longer period of observation with a bi-monthly observational interval has been recommended to enable decision on the rate of rise/sink and deformation of the building.

Abstract

The article presents an original optical system to measure displacements across joints or cracks in building structures. It describes the concept of system operation, algorithms to be followed and results of practical tests that have been performed.

The proposed solution is based on digital photos taken with a non-metric digital camera, modified by defining its internal orientation elements and correction of lens distortion during calibration, constituting the measurement instrument registering the pictures of markers. QR (Quick Response) codes are proposed to be the markers. Being digitally processed, a set of registered images allow visualising the measured size of occurred displacements.

Owing to this solution, it is possible to obtain data on a mutual position of two or more QR codes in the form of translation elements in 3D space and appropriate three orientation angles. Appointed elements are unequivocal in spatial interpretation and not limited by dimension.

As the tests performed by the authors show, the results are more than satisfactory. The proposed measurement technology is an objective system of data acquisition, suitable for automating the whole monitoring process of displacements of building structure elements concerning joints and cracks.

Abstract

Exchange of and access to spatial data is the principal goal of any Spatial Data Infrastructure, therefore, one of the key concepts of SDI is interoperability, especially semantic and syntactic. Whereas application schemas and quality issues are one of the aspects that have to be considered to ensure a successful data interchange in SDI.

Two types of application schema are widely used in the European SDI as well as in the Polish SDI. They cover both semantic and syntactic interoperability and are an integral parts of spatial data specifications and relevant regulations in the form of data models. However, working out accurate and correct application schemas may be a challenge.

Additionally, faulty or too complex application schemas can influence the ability for valid data interchange, and consequently, prevent achieving interoperability within SDI. Therefore, the capability to examine and estimate the UML and GML application schemas quality seems to be a worthwhile and important issue in the context of semantic and syntactic interoperability in SDI.

The main subject of this article it to set out the context of performed studies, among others, the role of application schema in the interoperable data exchange, issues related to the concept of quality and its measures.

Abstract

A geoid or quasigeoid model allows the integration of satellite measurements with ground levelling measurements in valid height systems. A precise quasigeoid model has been developed for the city of Krakow. One of the goals of the model construction was to provide a more detailed quasigeoid course than the one offered by the national model PL-geoid2011. Only four measurement points in the area of Kraków were used to build a national quasigeoid model. It can be assumed that due to the small number of points and their uneven distribution over the city area, the quasigeoid can be determined less accurately. It became the reason for developing a local quasigeoid model based on a larger number of evenly distributed points. The quasigeoid model was based on 66 evenly distributed points (from 2.5 km to 5.0 km apart) in the study area. The process of modelling the quasigeoid used height anomalies determined at these points on the basis of normal heights derived through levelling and ellipsoidal heights derived through GNSS surveys. Height anomalies coming from the global geopotential model EGM2008 served as a long-wavelength trend in those derived from surveys. Analyses showed that the developed height anomaly model fits the empirical data at the level of single millimetres – mean absolute difference 0.005 m. The developed local model QuasigeoidKR2019, similar to the national model PL-geoid2011, are models closely related to the reference and height systems in Poland. Such models are used to integrate GNSS and levelling observations. A comparison of the local QuasigeoidKR2019 and national PL-geoid2011 model was made for the reference frame PL-ETRF2000 and height datum PL-KRON86-NH. The comparison of the two models with respect to GNSS/levelling height anomalies shows a triple reduction in the values of individual quartiles and a mean absolute difference for the developed local model. These summary statistics clearly indicate that the accuracy of the local model for the city of Krakow is significantly higher than that of the national one.

Abstract

The subject of the considerations presented in the article is the question of the criteria according to which the comparables, in the market value estimating process, should be selected. As the most important in the selection of comparative properties, the factor of similarity in relation to the subject property (measured by the Euclidean distance) was considered. As the key issue, the similarity assessment criterion and the influence of the adopted critical value of this criterion on the accuracy of estimates were chosen. The analysis of the above was carried out with taking into account the role of the significance of independent variables (measured by their correlation with the vector of the dependent variable). The results of the simulation tests carried out in the variants set by the criteria adopted were presented. On this basis, it has been shown that there is a potential most relevant solution in the collection of obtainable estimation results. This solution corresponds with the smallest sum of the differences of model prices (accepted as known) and corresponding estimates. The found minimum occurs for a specific layout of the above criterion values only.

Abstract

The paper describes the problem of conversion of heights to the European Vertical Reference Frame 2007 for Poland (PL-EVRF2007-NH). The subject of the study is height data, and especially the detailed vertical reference network. The aim of the article is to present an alternative method of conversion to the one recommended by the Polish Head Office of Geodesy and Cartography. The proposed approach is characterised by a low implementation cost while maintaining the required accuracy.

The publication is illustrated by the case of Kętrzyn district (in the north-east part of Poland). The local reference network was converted from Kronstad’60 to PL-EVRF2007-NH in 2017.

Abstract

The article discusses a method applied for combining the results of Global Navigation Satellite Systems (GNSS) and 75-year old triangulation measurements to estimate the crustal movements in central western Bulgaria region. It was examined for joint analysis based on the results of GNSS with angular measurements of the first order triangulation network in Bulgaria during the period 1923–1930 year. As a result of the processing of GNSS and angular measurements, horizontal velocities of 15 points, strain rates, and rotation rates have been obtained. The results show dominating N–S extension at a rate of 1–2 mm/y and the deformation is not uniformly distributed over the studied area. The obtained results indicate the possibility of using old angular measurement of first-order triangulation points, together with GNSS data, to obtain estimates of the horizontal crustal movements.

Abstract

The study area is focused on the Kuril–Kamchatka Trench, North Pacific Ocean. This region is geologically complex, notable for the lithosphere activity, tectonic plates subduction and active volcanism. The submarine geomorphology is complicated through terraces, slopes, seamounts and erosional processes. Understanding geomorphic features of such a region requires precise modelling and effective visualization of the high-resolution data sets. Therefore, current research presents a Generic Mapping Tools (GMT) based algorithm proposing a solution for effective data processing and precise mapping: iterative module-based scripting for the automated digitizing and modelling. Methodology consists of the following steps: topographic mapping of the raster grids, marine gravity and geoid; semi-automatic digitizing of the orthogonal cross-section profiles; modelling geomorphic trends of the gradient slopes; computing raster surfaces from the xyz data sets by modules nearneighbor and XYZ2grd. Several types of the cartographic projections were used: oblique Mercator, Mercator cylindrical, conic equal-area Albers, conic equidistant. The cross-section geomorphic profiles in a perpendicular direction across the two selected segments of the trench were automatically digitized. Developed algorithm of the semi-automated digitizing of the profiles enabled to visualize gradients of the slope steepness of the trench. The data were then modelled to show gradient variations in its two segments. The results of the comparative geomorphic analysis of northern and southern transects revealed variations in different parts of the trench. Presented research provided more quantitative insights into the structure and settings of the submarine landforms of the hadal trench that still remains a question for the marine geology. The research demonstrated the effectiveness of the GMT: a variety of modules, approaches and tools that can be used to produce high-quality mapping and graphics. The GMT listings are provided for repeatability.

Abstract

We present a method of approximation of a deformation field based on the local affine transformations constructed based on n nearest neighbors with respect to points of adopted grid. The local affine transformations are weighted by means of inverse distance squared between each grid point and observed points (nearest neighbors). This work uses a deformation gradient, although it is possible to use a displacement gradient instead – the two approaches are equivalent. To decompose the deformation gradient into components related to rigid motions (rotations, translations are excluded from the deformation gradient through differentiation process) and deformations, we used a polar decomposition and decomposition into a sum of symmetric and an anti-symmetric matrices (tensors). We discuss the results from both decompositions. Calibration of a local affine transformations model (i.e., number of nearest neighbors) is performed on observed points and is carried out in a cross-validation procedure. Verification of the method was conducted on simulated data-grids subjected to known (functionally generated) deformations, hence, known in every point of a study area.