The analysis of morphometric parameters in hydrological modeling using GIS

The analysis of the physical-geographical conditions determines and influences the formation and the regime of the water resources from a hydrographic basin. This paper aims to analyse spatial data based on raster models, more precisely the terrain analysis, later used in hydrological modelling. For the elaboration of the digital model of the terrain, methods of interpolation of certain data are used - the level curves - after which, by running the ArcGIS program will result the structure of the irregular triangulation network (TIN). Next, based on the TIN model, a set of analyses is obtained regarding the morphology of the terrain: the slope map; slope exposure map, etc. The slope is one of the most important factors for controlling surface and intermediate water runoff. The exposure of the slopes depends very much on the direction of the slope of the land. With the help of the analysis of the slope and slope exposure it is possible to: calculate the solar lighting for each location in a region; find all slopes in the southern part of a mountainous region to identify locations where the snowmelt process will start earlier than in other areas, thus avoiding the danger of flooding due to runoff from the slopes and the danger of soil erosion; the value and speed of surface runoff; identify the spread and abundance of flora and fauna, precipitation; identify the productivity classes of the land; find all the north-facing slopes on a mountain as part for the search of the best ski slopes.

DESIGNING ENVIRONMENTALLY HAZARDOUS OBJECTS BY MEANS OF GEOGRAPHIC INFORMATION SYSTEMS

The article deals with the current problem of solid waste disposal. Also the use of geoinformation technologies in the design of environmentally hazardous facilities. The sequence of actions in case of reconstruction of a land plot for the construction of a solid waste landfill is described in detail. It shows how you can use geographic information systems to speed up and better accomplish the task. The convenience of using geographic information systems when planning such tasks is obvious. It is advisable to use geographic information systems when planning environmentally hazardous facilities. This is due to the complex nature of the problem. This requires the involvement of additional spatial data. It is the geographic information system that will allow the use of all data in the complex based on the principle of their spatial position. You can also use data models to support the creation, validation, and correction of information. In a geographic information system, you can create a geodatabase. This will create a 3D model of a solid waste landfill. The 3D model allows you to better represent the terrain. Creation of a triangulation network will allow to correlate all layers created in the geodatabase. The triangulation network is created from 3D terrain points. It allows you to get a three-dimensional model of a high-altitude polygon. This provides many possibilities in the future. It will be possible to interpret 3D models with high-precision engineering systems. This allows you to carry out any geometric measurements, build sections and profiles, as well as monitor activities at the solid waste landfill. Based on these data, it is possible to measure the volumes of household waste, areas, the height of the landfill in terms of the height of the actual relief and the level of groundwater, the altitude characteristics of the landfill and slopes to compare them with the standard indicators. The three-dimensional model will make it possible to identify inconsistencies between the actual boundaries of the polygon with the cadastral boundaries of the site allocated for these purposes. With the help of geographic information systems, simplicity, speed and clarity in the formation of conclusions and decision-making will be provided.

“Sucha Góra” (“Trockenberg”)—The Triangulation Point Doomed to Be Forgotten?

The current study documents the importance of research on preserved artifacts which were previously used to take measurements of the Earth, and their importance for cultural heritage. The article reviewed the available source documents presenting the history of the astrogeodetic control point of Sucha Góra-Trockenberg as a monument of the first order triangulation network, preserved in cartographic materials and as the starting point of local geodetic networks, used in mining until 2000 in the so-called Upper Silesian Coal Basin, located in the territory of Poland and the Czech Republic. In order to determine the history of the triangulation work and the dates that the geographic coordinates of the peak were determined, field journals and other available materials were analyzed. The interesting location of this astrogeodetic control point, being in the vicinity of a UNESCO site, as well as its location in a forest and park complex, justify undertaking activities related to the conservation and promotion of this cultural heritage site.

Designing a geodetic network through the search method based on the use of an undistorted model

General idea of the search method is provided. An information flowchart explaining themethod is presented. Formulas for evaluating the project of a geodetic network using the search method based on the undistorted model are given. The sequence of the mentioned design algorithm based on the undistorted model is developed. A computer program for evaluating the project in Visual Basic was compiled. The design and evaluation of the project of two networks, a triangulation geodetic and the one built according to the free stationing scheme was made. Both networks were constructed using the search method of nonlinear programming based on the undistorted model. The results of the evaluation of the triangulation network project coincided with those performed by the classical parametric method, which confirmed the correctness of the proposed algorithm for designing a geodetic network using the search method. The full weight matrix of coordinates of the defined points was obtained, and the average square error of the position of the weakest point in the network calculated.

USING REMOTE SENSING AND GIS TO CREATE GEOGRAPHICAL BASES FOR THEMATIC MAPS

The development of science always depends on technological progress. Cartography is rapidly changing and developing with the introduction of new computer technologies, such as GIS and remote sensing of the Earth. Recently, there have been qualitatively new types of cartographic products, in particular 3D terrain models, which in cartography are becoming a universal, optimal and operational method for displaying terrain. The article discusses a method for creating a three-dimensional digital terrain model in the form of an irregular triangulation network based on SRTM data and GIS technology on the example of the Khenti aimag of Eastern Mongolia.

Deformation analysis in central west Bulgaria using triangulation and GPS data

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.

The Struve Geodetic Arc: the development of the triangulation, technical possibilities, and the initiation of the project

The determination of parameters of the Earth's ellipsoid is quite a difficult task that gives no rest to scientists to this day. One of the more famous works is the Struve Geodetic Arc, which was stretched from the Black Sea to the Arctic Ocean by employing the method of a triangulation network and which is included in the UNESCO World Heritage Site list. However, until this project was implemented, many steps of scientific and technological advancement had to be taken, the entirety of which created the conditions for the realization of this project. A study of the method of triangulation measurements, the development of geodetic devices, the state politics of the Russian Empire in the 17th–19th centuries in the field of geodesy, and the development of triangulation during this period are presented in the article. Moreover, a study of the origins of the Struve Geodetic Arc project that led to such a grand result is conducted. The obtained results reveal that certain factors predetermined the favourable conditions for the successful execution of the project of this geodetic arc.

Influence of the Datum Definition on the Accuracy of Horizontal Geodetic Control Networks for Engineering Objects

For the construction of various civil engineering structures, particular care should be taken in the perspective of geodetic control. Therefore, the design and implementation of the geodetic network deserves special attention. This paper is focused on various aspects of datum definitions for tested micro-triangulation network. It was shown that the geometrical distribution of datum points in a minimally constrained solution has a great impact on the accuracy of the geodetic network. Estimates of the accuracies of individual station y-x coordinates, error circles and error ellipses, obtained by free adjustment, where the datum selection was independent of errors in fixed coordinates, revealed much better quality of control points.