Resumo em Inglês:

Abstract Several approaches concerning the use in positioning of GNSS (Global Navigation Satellite Systems) can be considered: systems, applied methods and errors that can affect the signals. Following the GLONASS (GLObal NAvigation Satellite System) constellation reestablishment (2011), there was renewed interest in its use with GPS (Global Positioning System). Different possibilities are available concerning applied methods, such as the virtual reference station (VRS) concept (it is possible to obtain data for a virtual station that does not physically exist, using data from a network). One of the main sources of error related to the GNSS signal, is the ionosphere. Many studies have been developed aiming to evaluate GPS positioning quality and influences that can affect it, but there are still several investigation possibilities concerning GLONASS. In this context, this research is intended to assess the GPS/GLONASS virtual data positioning performance considering regions and periods with different ionospheric behavior. A high correlation between the results from virtual and real data (Pearson’s correlation coefficients around 0.8) was noticed. GPS/GLONASS data performance presented better mean squared error results compared to GPS alone (average 3D improvement was 45 cm - 49%). In addition, it was possible to verify ionosphere influence in the positioning error, taking into account station region and period of the year.

Resumo em Inglês:

Abstract 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.

Resumo em Inglês:

Abstract The availability in real time of GNSS satellites orbits, clock corrections and code and phase biases provided the possibility of application of Real Time Precise Point Positioning (RTPPP). This paper presents the methodology concerning RTPPP and application to kinematic trajectories of airplane flight tests, but without using the carrier phase bias. So, it is PPP float solution. It requires RT positioning estimation, task that most of time presents certain difficulties due to loss of communication or of satellites during maneuvers of the airplane. However, if the corrections become unavailable for a certain period of time, the system starts using the ultra-rapid IGS orbits. The experiments were accomplished taking into account a case simulating RT and another in fact RT, but storing data and corrections for post processing. The PPP solutions obtained either simulating RT or in RT were compared against the PPP post processed solution that uses the final clock and orbit corrections. Then, statistics were generated to analyze the quality of both results. They were applied to kinematic trajectory that on average was 360 km/h, reaching about 600 km/h. The results provided accuracy better than the requisites for such cases which is of about 80 cm in height.

Resumo em Inglês:

Abstract Although universities conduct research in the SDI field, they have repeatedly erred when storing, preserving, and sharing their geospatial data. The general objective of this research is to develop a proposal for a Spatial Data Infrastructure (SDI) for the graduate programs of the Department of Earth Sciences at Federal University of Paraná (UFPR). In order to initiate the process of implementing UFPR’s academic SDI, a sample of the theses and dissertations of the aforementioned programs was collected. Subsequently, a survey of the metadata of the spatial study areas and publications was conducted, and finally, these metadata were made available as a catalog through GeoNetwork. The metadata, ISO TC-221, OGC and WC3 standards recommended by INDE-BR were adopted, and free and open source software was used. In this paper, the results of the metadata survey and their availability are presented in the form of a catalog, as well as a synthesis of the reflections made during the execution of the research, in order to help define the characteristics of academic SDIs in the country. The cataloging of historical metadata was found to be viable and to facilitate the dissemination of geospatial data to the scientific community.

Resumo em Inglês:

Abstract Technical graphic representation presents problems concerning the reduction of dimensionality from 3D to 2D. AEC (architecture, engineering and construction) projects usually adopt the top view paradigm with two-dimensional orthogonal projection. Recently, three major changes in technical representation were the alteration of orthogonal projection into a three-dimensional perspective view, inclusion of oriented object programing as in BIM (Building Information Model) and the interactions with AR (augmented reality). In this context, the present research evaluates the proposal of symbology based on color Hue as done in Cartography and the impact of three-dimensionality of the symbol in the identification of incompatibilities in a project of a residential building. An application of the visual variable color hue was proposed improve readability to representations and evaluations were performed with expert users, using representations in CAD 2D, BIM and AR in top and perspective views. Results indicate the color hue improve the cognitive process of read, interpret and find incompatibilities in civil projects, while the change of point of view contribute to interaction and manipulation in virtual environments. Both shows significance higher than 6% in ANOVA tests.

Resumo em Inglês:

Abstract The geodetic shoreline positioning has socioeconomic importance due to decision-making support related to the coastal zone. The Pernambuco state, Brazil, has established a state law no. 14.258/2010 sanctioned as part of Coastal Zone Management State Policy. The state act no. 42.010/2015 enacted the baseline information for Pernambuco shoreline. Considering that the shoreline mapping benefits from GNSS positioning using relative or absolute methods, the absolute PPP was the choice for legislation support. Therefore, the aim of this work is to depict about the Pernambuco state law and analyze the kinematic PPP accuracy applied to shoreline monitoring in order to attend the state act. The relative GNSS method was adopted as reference to assess the PPP accuracy for the Pernambuco shoreline. The analyses for each sector involved approximately one hour of kinematic GNSS data and the results indicate horizontal positioning accuracy around 0.50 m after PPP convergence period. Several PPP re-initialization has been detected, however, points considered outliers are removed from the final product. For this reason, recommendations are provided to improve the positioning applied for coastal zone monitoring. Although, the carried out experiments shows that PPP can be adopted as a practical tool to support the Pernambuco Coastal Zone Management.