Accuracy assessment of Lviv plans for the second half of the ХІХ century.
Students Name: Hoba Andrii Ivanovych
Qualification Level: magister
Speciality: Cartography
Institute: Institute of Geodesy
Mode of Study: full
Academic Year: 2020-2021 н.р.
Language of Defence: ukrainian
Abstract: Hoba A. I., Yurkiv M. I. (supervisor). Accuracy assessment of Lviv plans for the second half of the XIX century. Master’s thesis. ? Lviv Polytechnic National University, Lviv, 2020. Extended abstract. The Master’s thesis considers the topic about assessing the accuracy of Lviv plans for the second half of the XIX century. Plan in 1878 was published by Artaria & Co in a separate sheet from the administrative map of the Austrian cartographer and engineer Karl Richter van Kummersberg. This cartographic work was compiled on the basis of the Second Military Topographic Survey conducted in the Austrian Empire during 1855-1863, and occupies an important place in the study of architectural and urban planning of Lviv in Austrian times, before the great construction changes of the XIX century [1]. The plan of Lviv in 1894 was prepared by the city building administration by Juzef Chowanets and covered the most densely populated area of the city. The plan, which was later updated by the Society for the Development and Decoration of the City, was called the "Small Plan of Chowanets" [2]. Analysis of the accuracy of the old plans of Lviv is an important aspect in the study of these works, which allows you to assess their geometric features and obtain valuable information about the methods of their creation and processing techniques. Thus, it makes it possible to compare the cartographic, documentary and semantic value of ancient plans. The accuracy assessment methodology is based on the transformation and geometric analysis of sets of identical points on the old plan and the reference. Sets of control points are used to bring two cartographic products into a common coordinate system. The Helmert transformation with four parameters is used for such transformation. Identical points should be distributed over the entire area, ideally evenly, so that the resulting transformation key has a global character. According to the transformation key, multiquadratic interpolation is performed to construct a continuous surface from discrete data. The results of the latter make it possible to 8 graphically visualize the errors of the old plan in the form of displacement vectors, isolines of scale and rotation, which significantly speeds up and simplifies the study of the accuracy of the old plans. In addition, using the method of least squares a value that characterizes the positional accuracy of the ancient plan was obtained. All calculations and constructions were performed in the MapAnalyst software product [3]. The presented technique can be used for similar research on other cartographic works, and the obtained numerical results and graphical visualizations - to compare old plans with each other. The object of research are two plans of Lviv in second half of XIX century [4-5]. The subject of the research is geometric accuracy plans of Lviv of second half of XIX century. The purpose of the master’s thesis there is a study of geometric distortions of ancient plans of Lviv of the second half of the XIX century and an illustration of errors on the plane of plans by means of various graphic ways in the MapAnalyst software. As a result of the conducted researches it can be stated that both considered plans of Lviv of 1878 and 1894 are rather exact concerning angular measurements. The plan of 1878 has little counterclockwise significance, and the plan of 1894 is clockwise. However, the RMSE of angular measurements for the latter is much smaller. For linear measurements and positional errors, the accuracy is slightly worse. The values of the RMSE of these values also differ in both plans, and indicate a greater accuracy of the plan of 1894 for linear measurements compared to the plan of 1878. This fact is also confirmed by graphic illustrations of errors in the form of a grid of distortions and isolines of scale and rotation. The results of the cartometric analysis are influenced by a number of different factors. The following two important factors can be considered decisive in our case, the choice of a set of identical points for calculating the transformation key and the interpolation technique used to reconstruct a solid surface from discrete 9 data. However, despite the above facts, the results achieved can be considered valid. None of the factors, apparently, played such an important role that would significantly affect the results of cartometric analysis. Key words: plan of Lviv, cartometric analysis, Helmert transformation, displacement vectors, distortion greed, scale and rotation isolines, root mean square error(RMSE)/ References: 1. Sossa, R. (Eds), Kryshtalovych, U., ? Shyshka, O. (2016). Kartohrafichni vydannya L’vova: Kataloh vystavky. L’viv, 6-8 hrudnya 2016. [Cartographic publications of Lviv: Exhibition Catalog. Lviv, December 6-8, 2016]. Lviv: Lviv Polytechnic Publisher. 28 p. (in Ukrainian) 2. Linda, S., Oleshko, O. & Ivanochko, U. (2004) Doslidjennia terytorialnoho rozvytku Lvova avstriiskoho period (1772-1918) na osnovi cartografichnoho materialu [Study of the territorial development of Lviv of the Austrian period (1772–1918) on the basis of cartographic material]. Visnyk nacionalnoho universytetu Lvivska Polytechnika, vol.505: Architectura, pp. 127-141. (in Ukrainian) 3. MapAnalyst [ electronic resource]: - Access mode: https://mapanalyst.org 4. Plan von Lemberg / [Carl Ritter Kummerer von Kummersberg]. Scale 1:10 800. Lviv National Scientific Library of Ukraine named after V. Stefanyk, КК 4904. 5. Plan kr. stol. Miasta Lwowa /[Juzef Chovanjec] Scale 1:7 200. Lviv National Scientific Library of Ukraine named after V. Stefanyk,