In theory of regular projection of a surface into another surface, the term of the indicator of projection deformations, as a topological substitute of an infinitesimal circle of a unit radius is known. In the case of regular projection of a three-dimensional space into a three-dimensional space, a three-axis ellipsoid is the indicator of projection deformations, being the topological substitute of an infinitesimal unit sphere. This paper presents the attempt to analytically describe the infinitesimal unit sphere in the original space and its topological substitute in the projected space.

The paper gives a strategy of geographic information modelling, being comprised in the European Standards (as formulated by the CENffC 287) and also subjected to national standardisation. Main goals of the standardisation are formulated, which include proper arrangement of this domain, as well as formation of prerequisites for reasonabel development of GIS in diversified environments. The last one is necessary to provide effective transfer of geographic data between different GIS installations. There are formulated and defined basic concepts of information modelling, such as conceptual schema, application schema, entity - relationship method, as well as of the EXPRESS language, being the main formal means of the presented methodology. The present state of the national standardisation activities is outlined.

In the paper the model of the disturbing potential based on the lower-degree harmonic spherical polynomials and the local density model of topographic masses has been proposed. Topographic masses are represented by DTM. The model parameters are fixed by the use of quasigeoid heights as well as a dense network of gravity points. Preliminary analyses of the model's robustness of gravimetric data errors have also been included.

In this paper there are presented results of applying the methods of the time series analysis to the problem of recognizing small boats. It has been showed that the acoustic signals of the boats can be classified by means of clustering algorithms.

The paper presents such a method of distribution of observations in a surveying network, which allows to meet requirements concerning the network with the possibly lowest direct costs of survey. As a result, a set of azimuths, sides, angles and GPS chords which can be measured in a given network is obtained; then the selection of a subset, which meets the above criteria may be performed. The OPTY98 computer system, which time of calculation may be accepted by an arbitrary network, has been developed for the proposed algorithm. Required data as well as obtained results are presented using the example of the Refe network.

The paper is organized into two sections. The first sets the background for data integration, and identifies some of the key issues that need to be considered. The second describes possible solutions of problems connected with the data integration. The steps of integrating data coming from different databases, datasets and data files are described in order to create a seamless geodatabase.

Simplification of a shape of a coastline is one of the best-described issues of quantitative generalisation. Schematisation of a coastline shape is a process, which may be relatively easily described by means of an algorithmic formula. However, the majority of algorithms consider only geometric aspects and river and road networks are generalised by means of the same parameters. Many described methods of direct transfer of subjective ways of manual generalisation to computer systems have turned out to be ineffective. Application of fractal analysis is an attempt aiming at objective implementation of a process of automated cartographic generalisation by means of selection of parameters of algorithms of simplification of lines, preceded by analysis of local geometric features of modelled objects. The, so-called mono-fractal dimension of objects, commonly used in cartometric analysis, DJ, specifies the averaged level of filling of available space only. The multi-fractal dimension of analysed objects, as, for example of a coastline, determined by means of a method proposed by the author, specifies the multi-fractal spectrum of dimensions, D(q). The range of obtained values of the parameter DJ( l .05-e- 1.42) allows for assumption that the coastline has multi-fractal properties. In this paper the author proposes development of new descriptive and research tools, which may be used for investigation of local geometric features of objects presented on a map, as well as for simplification of shapes of objects in the process of cartographic generalisation.

This paper presents an analysis of various types of maps and other geographical scenes from users point of view. The division of people according to their perceptional abilities allows to compare the pragmatic properties of cartographical means being in map users' disposal. Visually, tactile, kinesteticly and sonicly percepted scenes as well as multimedia! realisations have been considered to determine differentiation of their usability for recognition of general and particular spatial characteristics of presented map contents as reflection of reality in user's mind. Very composed problems of range of definitions of maps and cartography has been considered (on the base of ICA 's definitions formulated in 1995) with a view to their correctness since the latest rapid impact of new technology on the discipline. According to author's opinion new definition of a map should embrace only types of realisations of broadly treated scenes fulfilling precisely determined list of essential properties connected with cognitive as well as applicable map's functions.

In this paper the general solution of nonlinear satellite pseudorange equation system has been given. This solution was obtained by the application of the new positional transformation determining relations between the points in three-dimension space. It has been proved that computation of the position does not require knowledge of the light speed, occuring in pseudorange measurements, or determination of approximate coordinates. The general solution allows one to obtain all possible solutions including complex conjugate positions. This work has also stated that there exists some space regions in which it is not possible to determine the positions in the domain of real numbers. This is especially important in navigation of objects moving in the space.

The edge extraction seem to be an important step in matching of aerial images for 3D city and also in analysis and interpretation of satellite imagery for middle scale mapping production. Since twenty years the problem of edge and line extraction is still actual. The degree of full automation for edge and line extraction is in the way to advance. In practice there are several groups of methods using for extraction of edges and lines. The methods based on the differential geometry are often useful to solve this tasks. This paper presents a new algorithm approach to find the coefficients of function fitting to an edge in 2D image that is written by Fouriers expansion. Basing on the gradients of edge pixel that is Gausians line-spread function, the fitting function to edge should be constituted. For improving reliability of linking edge pixels into line it is proposed to apply three thresholds in which one is based on the finding correlation coefficients of grey levels between the neighbouring pixels in the image window.