Cláudia Pereira Krueger

First Results of Relative Field Calibration of a GPS Antenna at BCAL/UFPR (Baseline Calibration Station for GNSS Antennas at UFPR/Brazil)

The precise and accurate determination as well as the usage of individual calibration values of GNSS (Global Navigation Satellite Systems) antennas are of fundamental importance for state-of-the-art GNSS positioning at millimeter accuracy level, especially concerning the precise determination of the height component. Calibration values can be determined in various ways (relative vs. absolute, chamber vs. field). Within the transnational research project “PROBRAL: Precise positioning and height determination by means of GPS – Modeling of errors and transformation into physical heights”, the first relative antenna calibration field of Latin America was established.

MODELAGEM PREDITIVA DE LINHA DE COSTA UTILIZANDO REDES NEURAIS ARTIFICIAIS

Estudar modelagens atraves de dados geodesicos temporais com a possibilidade de predizer a posicao de linha de costa e uma tarefa importante e pode auxiliar significativamente na gestao costeira. A area de estudo neste trabalho se refere ao municipio de Matinhos no estado do Parana, Brasil. As linhas de costa temporais utilizadas para testar a modelagem preditiva sao provenientes respectivamente da fotogrametria analogica para anos 1954, 1963, 1980, 1991 e 1997 e de levantamentos geodesicos utilizando GPS (Global Position System) para 2001, 2002, 2005 e 2008 (como controle). Dois testes com as redes neurais artificiais foram organizados mudando alguns parâmetros como: arquitetura, numero de neuronios nas camadas ocultas e algoritmos de treinamentos. Quando comparados o valor dos residuos entre a predicao e a linha de costa de controle, os melhores resultados estatisticos indicam que o MAPE (mean absolute percentage error) sao 0,28% utilizando a rede neural parcialmente recorrente de Elman com o algoritmo de treinamento quase-Newton e 0,46% para o caso da rede neural perceptron multicamadas com o algoritmo de treinamento utilizando o metodo Bayesiano com regularizacao.

Establishing A Gnss Receiver Antenna Calibration Field in the Framework Of Probral

PROBRAL - Precise positioning and height determination by means of GPS: Modeling of errors and transformation into physical heights is the name of a joint venture between the Department of Geomatics (DGEOM), Federal University of Parana (UFPR), Curitiba (Brazil) and the Geodetic Institute (GIK), University Karlsruhe (TH), Karlsruhe (Germany). The aim of this research project, which started in 2006 and is founded by the Brazilian academic exchange service CAPES and the German academic exchange service DAAD, is to validate and to improve the quality of GNSS-based positioning, especially concerning the height component.

Classificação fuzzy da vulnerabilidade aos processos costeiros em Pontal do Paraná, Brasil

The classification of the vulnerability for coastal processes considering both natural factors and anthropogenic interference can contribute for Integrated Coastal Zone Management (ICZM). This contribution develops a fuzzy system to classify the vulnerability of coastal processes in the coastal zone of Pontal do Sul, PR, Brazil. The study area was divided into three sectors with different characteristics, which provided diverse inputs to test this fuzzy system. Considered input variables are set as the follows: anthropogenic interference, average wave height, tidal range and the influence of the estuary in the region. The output of the final classification presents three linguistic labels, which represents three levels of vulnerability as stable, moderate and unstable. The results by the defuzzification in the fuzzy system are numerical values in a scale ranging from 0 to 8. The following values have been obtained as 5.9, 6.7 and 1.3; for the three sectors indicating unstable, unstable and stable classification respectively. In order to corroborate the efficacy of modeling, the results were compared with existing classification of the study area. The method can be an alternative approach for the expert’s role in decision-making in related studies.

A INFLUÊNCIA DOS PARÂMETROS DE CALIBRAÇÃO DE ANTENAS GPS NAS ALTITUDES ELIPSOIDAIS NO POSICIONAMENTO RELATIVO ESTÁTICO

Alta acuracia em posicionamento GPS (Global Positioning System) e obtida atraves da eliminacao parcial ou total dos erros presentes nas observacoes, particularmente os sistematicos. Um deles e o erro de centro de fase da antena GPS. Ele e diretamente dependente da antena utilizada, visto que cada uma delas tem suas caracteristicas proprias de construcao e recepcao do sinal GPS. Portanto, e de extrema importância o conhecimento individual do centro de fase da antena (Phase Center Offset – Phase Center Variation). Entre outros, existem parâmetros fornecidos pelo NGS (National Geodetic Survey), no entanto, esses valores sao medios e nao sao valores proprios das antenas usadas nos posicionamentos GPS. Os parâmetros individuais das antenas, neste trabalho, foram fornecidos pela BCAL/UFPR (Base de Calibracao de Antenas GNSS na UFPR). Realizaram-se posicionamentos GPS em 9 (nove) pontos. Estes foram distribuidos em 3 (tres) grupos de linhas de base (9km, 45km e 105km). Para cada comprimento de linha de base os rastreios GPS seguiram simultâneos aplicando o Metodo de Posicionamento Relativo Estatico, com um intervalo de gravacao de dados de 15 segundos e mascara de elevacao de 15°. Foram encontradas diferencas na comparacao das altitudes elipsoidais e no comprimento das linhas de bases, quando nao se utilizou parâmetros, na ordem do centimetro. De fato, os valores obtidos da BCAL/UFPR sao provenientes da utilizacao dos proprios equipamentos, desta forma, fieis as antenas utilizadas, enquanto que os fornecidos pelo NGS sao valores medios. Destaca-se que a BCAL/UFPR e a primeira base de calibracao de antenas GPS/GLONASS no Brasil e na America Latina.

Highly Precise Positioning and Height Determination using GPS : Results of a PROBRAL project by Universidade Federal do Paraná (UFPR, Curitiba, Brazil) and Karlsruhe Institut für Technologie (KIT, Karlsruhe, Germany). (KIT Scientific Reports ; 7604)

This book presents some representatively selected results and experiences gained within the bilateral PROBRAL program funded by the academic exchange services CAPES and DAAD. During the time period 2006-2009 the joint international research project was established between the Postgraduate Programme in Geodetic Sciences of the Department of Geomatics of the Federal University of Parana (UFPR, Curitiba, Brazil) and the Geodetic Institute of Universitat Karlsruhe TH (now KIT, Karlsruhe, Germany).

CIÊNCIAS GEODÉSICAS NA GERAÇÃO DE SUBSÍDIOS PARA PLANEJAMENTO E GESTÃO DAS ZONAS COSTEIRAS

This paper presents a discussion about the tools geodetic sciences used to support the planning and management in coastal areas, including Remote Sensing and GPS. The aggregation of this knowledge gives subsidies for making decisions involving the coastal population are of essential importance for the development and implementation of planning policies and management of coastal areas. In this paper we experiments are presented research groups Positioning and Navigation Techniques Based on Spatial and for Photogrammetry and Remote Sensing Course Graduate in Geodetic Sciences in coastal regions. Key words: Remote Sensing , Navigation Based in Space Techniques, planning, management the coastal areas.