EXTRAÇÃO AUTOMÁTICA DE REDES DE DRENAGEM A PARTIR DE MODELOS DIGITAIS DE ALTITUDE

A obtenção da rede de drenagem por técnicas manuais é uma tarefa tediosa e demorada. Na literatura internacional encontram-se vários métodos para a extração automática desta rede a partir de Modelos Digitais de Altitude (Digital Elevation Models - DEM). Entretanto, os principais softwares desenvolvidos no Brasil, voltados para a geração de bases de dados cartográficos e para Sistemas de Informação Geográfica, não dispõem deste tipo de ferramenta. Assim, encontrou-se no programa SKEL, desenvolvido na Universidade de Israel e que é de domínio público, uma alternativa simples para este fim. Com o presente trabalho, descreve-se uma metodologia onde se utiliza o programa SKEL para a extração da rede de drenagem a partir de um DEM. A grande vantagem encontrada com este método é que o processo de extração pode ser realizado em aproximadamente 10 minutos para uma área aproximada de 25 km2. As principais limitações dizem respeito aos passos intermediários de conversão dos formatos dos arquivos, bem como da geração do DEM. Abstract The obtainment of drainage network from manual techniques is a tedious and time consuming task. In the international bibliography there are methods to automatic extraction of drainage networks from Digital Elevation Models (DEM). However, the main softwares developed in Brazil which aim at producing digital cartographic data bases and Geographical Information Systems (GIS) do not present this kind of tool. So, we found in SKEL program, which was developed at the Israel University, a simple alternative to extract the drainage network. With the present work we describe a metodology where the SKEL program is used to extract the drainage network from a DEM. The greatest advantage found in this method is that the extraction process can be performed in about 10 minutes to an area of 25 km2. The main restriction deals with intermediary processes of conversion of file formats, as well as DEM generation

LANDMARKS EVALUATION WITH USE OF QR-CODE FOR POSITIONING INDOOR ENVIRONMENT

People tend to lose their sense of direction in closed environments and the role of indoor maps is to assist the user in navigating in these spaces, through understanding the environment, identifying reference points or positioning. Among the several forms of achieving positioning in indoor environments, this research used the method based on image recognition through identification of QR-Code labels, because of their low cost, easy implementation, and because their accuracy is not affected by the environment. As such, this article presents the use of QR-Code markers affixed to possible reference points to determine user positioning in an indoor environment using a mobile device. This study seeks to discover which are the most appropriate sites for placing QR-Codes in an environment, by evaluating what reference points and what type thereof are most used in indoor environments. This study is therefore based on the hypothesis that if initial positioning is obtained only through reference points this is sufficient for users to orient themselves. Through analysis of the results obtained from navigation tasks done by users we were able to obtain data regarding elements most cited as references. The results show that people orient themselves in distinct ways in the same environment and use as their main reference points structural elements of the environment such as stairways, lifts, and decision-making points; in general structural reference points were those most used to support orientation and navigation

EVALUATION OF MOBILE DEVICE INDOOR MAPS FOR ORIENTATION TASKS

This research investigates subjective user preference for using Floor Plans and Schematic Maps in an indoor environment, and how users locate and orient themselves when using these representations. We sought to verify the efficiency of these two kinds of digital maps and evaluate which elements found in physical environments and which elements found in the representations influence the user spatial orientation process. Users answered questions and performed orientation tasks which indicated their level of familiarity with the area being studied, their understanding of the symbology used, and their identification of Points of Interest (POI) in the environment. The initial results indicated a preference for the Schematic Map, because users thought that the symbology used on the map adopted was easy to understand

Evaluation of subjective preferences regarding indoor maps: comparison of schematic maps and floor plans

Ponencias, comunicaciones y pósters presentados en el 17th AGILE Conference on Geographic Information Science "Connecting a Digital Europe through Location and Place", celebrado en la Universitat Jaume I del 3 al 6 de junio de 2014.In this study, we investigate subjective preferences regarding floor plans and schematic maps in the use of a map in an indoor environment. To achieve this, we performed a qualitative experiment with a random user sample; the survey was carried out remotely. The survey was conducted in Portuguese and English, and users were asked to answer questions, using two different maps:a floor plan and a schematic map. In the sequence, users were asked questions about their preferences regarding map use in an indoor environment. Users also answered questions about the positive and negative aspects of using a schematic map in an indoor environment. The initial results do not indicate a preference for one kind of map, but show that users found the symbology adopted in the schematic map easier to understand

Extração automatica de redes de drenagem a partir de modelos digitais de altitude

Orientador: Quitino DalmolinCo-orientador: Antonio Jose Berutti VieiraDissertação (mestrado) - Universidade Federal do ParanáResumo: A obtenção da rede de drenagem por técnicas manuais é uma tarefa tediosa e demorada. Na literatura internacional encontram-se vários métodos para a extração automática desta rede a partir de Modelos Digitais de Altitude (Digital Elevation Models - DEM). Entretanto, os principais "softwares" desenvolvidos no Brasil, voltados para a geração de bases de dados cartográficos e para Sistemas de Informação Geográfica, não dispõem deste tipo de ferramenta. Assim, encontrou-se no programa SKEL, desenvolvido na Universidade de Israel e que é de domínio público, uma alternativa simples para este fim. Com o presente trabalho, descreve-se uma metodologia onde se utiliza o programa SKEL para a extração da rede de drenagem a partir de um DEM. A grande vantagem encontrada com este método é que o processo de extração pode ser realizado em aproximadamente 10 minutos para uma área aproximada de 25 km . As principais limitações dizem respeito aos passos intermediários de conversão dos formatos dos arquivos, bem como da geração do DEM.Abstract: The obtainment of drainage network from manual techniques is a tedious and time consuming task. In the international bibliography there are methods to automatic extraction of drainage networks from Digital Elevation Models (DEM). However, the main softwares developed in Brazil which aim at producing digital cartographic data bases and Geographical Information Systems (GIS) do not present this kind of tool. So, we found in SKEL program, which was developed at the Israel University, a simple alternative to extract the drainage network. With the present work we describe a metodology where the SKEL program is used to extract the drainage network from a DEM. The greatest advantage found in this method is that the extraction process can be performed in about 10 minutes to an area of 25 km2. The main restriction deals with intermediary processes of conversion of file formats, as well as DEM generation

The use of spatial terms ‘NEAR’, ‘VERY NEAR, ‘NEXT TO’, ‘SIDE BY SIDE and ‘NEARBY’ in the descriptions of spatial configurations

Spatial relations are words used to describe the existing relationships between elements present in environments. In the Natural Language, that is, that of the representations present geographical spatial organizations often seen in the daily lives of individuals, the user when reporting their location, uses a significant amount of spatial relations. Consequently, one has the difficulty of defining which of these words are suited to be used in spatial descriptions, in the sense of transmitting spatial information in a clear and precise way. Aiming to foster research in this field, an experiment was carried out with volunteers natives Brazilian Portuguese language in which the use of five spatial relations denoting distances in qualitative terms was sought. The results obtained showed that, although they present similar understandings, the incorrect use of one of these spatial relations can transmit to the receiver of the message an erroneous spatial information. In addition, it was observed a tendency in choosing a specific spatial relation as the distance between the reference elements increases with each other