A Digital Terrain Model (DTM) is a continuous representation of a ground surface landform that is commonly used to produce topographic maps. DTMs are created by integrating data obtained from a wide ...range of techniques including remote sensing and land surveying. Quality assessment of data is a critical parameter for DTM production and it relies heavily on statistical methods. In contrast, visual methods are generally neglected despite their potential for improving DTM quality. In this paper, several enhanced visual techniques for quality assessment are described and illustrated with areas and datasets selected from Slovenia and the planet Mars. Four classes of visual methods are defined: visualisations according to spatial analytical operations based on one or multiple datasets; visualisations according to spatial statistical analysis; non-spatial visualisations; and other visualisation techniques/other algorithms. The four classes generate different outputs: the first two produce thematic maps, while the third is used for non-spatial visualisation. The fourth class gathers other possible visualisations and algorithms. It is suggested that applying visual methods in addition to the more objective statistical methods would result in a more efficient improvement of the quality.
Topografski podatki, kot pomemben del Nacionalne prostorske podatkovne infrastrukture, so bili v letih po osamosvojitvi Slovenije deležni velike pozornosti, postali so splošno dostopni, bili so ...dopolnjeni in medsebojno usklajeni. V zadnjem desetletju pa se je vlaganje v topografske podatke v Sloveniji zelo omejilo, zato danes nikakor več ne moremo biti zadovoljni z njihovim stanjem. V prispevku pregledno predstavljamo stanje topografskih podatkov v Sloveniji, analiziramo njihovo kakovost in ustreznost za potencialne in dejanske uporabnike. Posvetimo se izvornim posnetkom stanja, kot je sistemsko ciklično aerosnemanje (CAS), in iz njega izvedenemu proizvodu, ortofotu. Kakovost ortofota je precej odvisna od kakovosti modela reliefa. Topografski podatki so vodeni posamično v sklopu posameznih vsebinskih baz (REZI, ZK GJI, grafični del katastra stavb) ter združeno v topografskih bazah in kartah različnih ravni podrobnosti (DTK 5, DTK 25, DTK 50, sistem DPK). Analizirano stanje primerjamo s stanjem v nekaterih sosednjih ali primerljivih državah ; Topographic data, an important part of the National Spatial Data Infrastructure, have been given serious attention since Slovenia’s independence. It has become publicly available, updated and harmonised. Financing of topographic data in Slovenia has significantly decreased over the previous decade. As a result, the present status is far from acceptable or expected. The current status of the topographic data, as well as its quality and usability for potential users is discussed in this article. The overview starts with basic source data, aerial surveys, photographs and orthophotos. The quality of orthophotos largely depends on the DTM quality. Topographic data is nowadays organised in thematic datasets (geographical names, building cadastre, etc.) or joined in datasets of different levels of accuracy and details. The status in Slovenia is compared to those in some neighbouring and other comparable countries.
The aim of our study is a detailed determination of the local speeches areas which are parts of the Slovenian Linguistic Atlas (SLA). The SLA is a geolinguistic project designed in the 1930s with its ...publishing expected in 2010. One of the goals of this subproject is to analyse the impact areas and to geographically allocate the local speeches for a more precise determination of the isoglosses. This will consequently enable a better understanding of the nature of a particular speech. Various evidences that influenced formation of the particular speech have been analysed with the geographic information system (GIS). The evidences are intra- and extra-linguistic indicators, i.e. geographic and historic. The allocation of the speeches has been generated through the innovative variables, which describe potential delimitations considering geographic criteria with help of the database of settlements in Slovenia. Further study is going to develop twofold: The first is the continuation of the research in dialectometry, and the second is to support these statements with spatial modelling and simulations. The developed methodology could be implemented to the wider areas in Central Europe.
A spatial ETL tool that allows interoperability between spatial and non-spatial data is presented in this article. The primary goal of the tool is to provide spatial data processing, and ...transformation among various data formats. This is made possible by the ETL process, which extracts, transforms and loads data. The use of spatial data has become significant in everyday life, because only correctly applying the data enables users to extract the true value spatial data offers. The main purpose of this article is to demonstrate the capability and usability of the spatial ETL tool, in order to introduce a more detailed definition of the ETL process to acquaint the reader with the FME Desktop tool, and to demonstrate the applicability of the tool in two case studies. In the first case, a unified spatial data warehouse is built from non-homogeneous data warehouses in order to assess the impacts and effects the geological basis had on the amount of damage to buildings in the 2004 earthquake.
An algorithm of automated karst depression recognition uses a digital terrain model (DTM) and mainly applies the methods of a moving window with a kernel size of 3 × 3 cells using focal functions. It ...is divided into four parts: watershed calculation, depression delineation, higher level depression delineation and elimination of non-karst depressions. The essential part of the algorithm is the delineation of depression by the elevation of the lowest border cell of watershed. Depressions at higher levels are recognised by filling previously recognised depressions. The performance of algorithm was tested on test area in the Kras region (Slovenia) using DTMs with a spatial resolution of 12.5 m and 3 m. The results mainly depend on the DTM characteristics and quality, especially of their spatial resolution. PUBLICATION ABSTRACT
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