Wyszukiwarka
dr inż. Marek Zienkiewicz
Publikacje
Filtry
wszystkich: 16
Katalog Publikacji
Rok 2024
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Wybrane teoretyczne i aplikacyjne własności Msplit estymacji
PublikacjaPraca składa się z siedmiu rozdziałów. Rozdział pierwszy jest poświęcony M-estymacji traktowanej jako uogólnienie MNW. Szczególną uwagę zwrócono w nim na odporną klasę M-estymatorów stanowiącą bazę porównawczą w analizie odporności Msplit estymatorów. W rozdziale drugim przedstawiono teoretyczne podstawy Msplit estymacji oraz jej rozwinięć i przypadków szczególnych (kwadratowej Msplit estymacji, Shift-Msplit estymacji i Msplit...
Rok 2023
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Assessing historical church tower asymmetry using point cloud spatial expansion
PublikacjaChurch towers are key cultural heritage. In theory, towers are vertical, while facade elements are symmetrically positioned around the tower axis. However, during service of a structure, building and lifetime conditions cause deviations, with associated risks. Laser scanning point clouds can be used to assess the structural state but a universal approach was missing. The proposed algorithm first estimates the tower inclination,...
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Matrix Strengthening the Identification of Observations with Split Functional Models in the Squared Msplit(q) Estimation Process
PublikacjaThis article addresses the issue of raising the level of identification of observations with either single or more split functional models in the squared Msplit(q) estimation process. The theoretical part of the study presents the theoretical grounds for the classical method for estimating parameters in a split functional model and proposes a modification of the computational algorithm to increase the quality of the determinations...
Rok 2022
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Identification of Unstable Reference Points and Estimation of Displacements Using Squared Msplit Estimation
PublikacjaThe article presents a new version of the method for estimating parameters in a split functional model, which enables the determination of displacements of geodetic network points with constrained datum. The main aim of the study is to present theoretical foundations of Msplit CD estimation and its basic properties and possible applications. Particular attention was paid to the efficacy of the method in the context of geodetic...
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Impact of cross-section centers estimation on the accuracy of the Point cloud spatial expansion using robust M-estimation and Monte Carlo simulation
PublikacjaThe point cloud spatial expansion (PCSE) method creates an alternative form of representing the shape of symmetrical objects and introduces additional descriptive geometric parameters. An important element of the procedure is determining the course of the axis of symmetry of cylindrical objects based on cross-sections of point clouds. Outliers occurring in laser measurements are of great importance in this case. In this study,...
Rok 2021
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Empirical analyses of robustness of the square Msplit estimation
PublikacjaThe paper presents Msplit estimation as an alternative to methods in the class of robust M-estimation. The analysis conducted showed that Msplit estimation is highly efficient in the identification of observations encumbered by gross errors, especially those of small or moderate values. The classical methods of robust estimation provide then unsatisfactory results. Msplit estimation also shows high robustness to single gross errors...
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Estimators of covariance matrices in Msplit(q) estimation
PublikacjaThis paper proposes methods for the determination of covariance matrices of Msplit(q) estimators. The solutions presented here allow Msplit(q) estimation to be supplemented by the operations from the domain of accuracy analysis (especially that concerning estimators of parameters). Theoretical forms of covariance matrices of Msplit(q) estimators were established using the empirical influence functions and the equivalent covariance...
Rok 2020
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3D POINT-CLOUD SPATIAL EXPANSION BY TOTAL LEAST-SQUARES LINE FITTING
PublikacjaPoint-cloud spatial expansion (PCSE) allows the creation of a new pointcloud form that presents an alternative geometry of an entire object in a single spatial view. Spatial expansion facilitates the analysis process and introduces an additional spatial parameter describing the point cloud. An important element of the PCSE method is determining the position of the axis of symmetry of a symmetrical object: the procedure for determining...
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Determination of an adequate number of competitive functional models in the square Msplit(q) estimation with the use of a modified Baarda’s approach
Publikacja
Rok 2019
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A Novel Approach of Using Selected Unconventional Geodesic Methods of Estimation on VTS Areas
PublikacjaThe Vessel Traffic Service (VTS) systems belong to the fundamental tools used in ensuring a high level of safety across sea basins with heavy traffic, where the presence of navigational hazards poses a great risk of collision or a ship running aground. In order to determine the mutual location of ships, VTS systems obtain information from different facilities, such as coastal radar stations, AIS, and vision systems. Fixing a ship’s...
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Deformation Analysis of Geodetic Networks by Applying M split Estimation with Conditions Binding the Competitive Parameters
Publikacja
Rok 2017
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Application of Square Msplit Estimation in Determination of Vessel Position in Coastal Shipping
Publikacja -
Multi split functional model of geodetic observations in deformation analyses of the Olsztyn castle
Publikacja
Rok 2016
Rok 2015
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