Traditional imagery—provided, for example, by RGB and/or NIR sensors—has proven to be useful in many agroforestry applications. However, it lacks the spectral range and precision to profile materials and organisms that only hyperspectral sensors can provide. This kind of high-resolution spectroscopy was firstly used in satellites and later in manned aircraft, which are significantly expensive platforms and extremely restrictive due to availability limitations and/or complex logistics. More recently, UAS have emerged as a very popular and cost-effective remote sensing technology, composed of aerial platforms capable of carrying small-sized and lightweight sensors. Meanwhile, hyperspectral technology developments have been consistently resulting in smaller and lighter sensors that can currently be integrated in UAS for either scientific or commercial purposes. The hyperspectral sensors’ ability for measuring hundreds of bands raises complexity when considering the sheer quantity of acquired data, whose usefulness depends on both calibration and corrective tasks occurring in pre- and post-flight stages. Further steps regarding hyperspectral data processing must be performed towards the retrieval of relevant information, which provides the true benefits for assertive interventions in agricultural crops and forested areas. Considering the aforementioned topics and the goal of providing a global view focused on hyperspectral-based remote sensing supported by UAV platforms, a survey including hyperspectral sensors, inherent data processing and applications focusing both on agriculture and forestry—wherein the combination of UAV and hyperspectral sensors plays a center role—is presented in this paper. Firstly, the advantages of hyperspectral data over RGB imagery and multispectral data are highlighted. Then, hyperspectral acquisition devices are addressed, including sensor types, acquisition modes and UAV-compatible sensors that can be used for both research and commercial purposes. Pre-flight operations and post-flight pre-processing are pointed out as necessary to ensure the usefulness of hyperspectral data for further processing towards the retrieval of conclusive information. With the goal of simplifying hyperspectral data processing—by isolating the common user from the processes’ mathematical complexity—several available toolboxes that allow a direct access to level-one hyperspectral data are presented. Moreover, research works focusing the symbiosis between UAV-hyperspectral for agriculture and forestry applications are reviewed, just before the paper’s conclusions.
Due to strong improvements and developments achieved in the last decade, it is clear that applied research using remote sensing technology such as unmanned aerial vehicles (UAVs) can provide a flexible, efficient, non-destructive, and non-invasive means of acquiring geoscientific data, especially aerial imagery. Simultaneously, there has been an exponential increase in the development of sensors and instruments that can be installed in UAV platforms. By combining the aforementioned factors, unmanned aerial system (UAS) setups composed of UAVs, sensors, and ground control stations, have been increasingly used for remote sensing applications, with growing potential and abilities. This paper’s overall goal is to identify advantages and challenges related to the use of UAVs for aerial imagery acquisition in forestry and coastal environments for preservation/prevention contexts. Moreover, the importance of monitoring these environments over time will be demonstrated. To achieve these goals, two case studies using UASs were conducted. The first focuses on phytosanitary problem detection and monitoring of chestnut tree health (Padrela region, Valpaços, Portugal). The acquired high-resolution imagery allowed for the identification of tree canopy cover decline by means of multi-temporal analysis. The second case study enabled the rigorous and non-evasive registry process of topographic changes that occurred in the sandspit of Cabedelo (Douro estuary, Porto, Portugal) in different time periods. The obtained results allow us to conclude that the UAS constitutes a low-cost, rigorous, and fairly autonomous form of remote sensing technology, capable of covering large geographical areas and acquiring high precision data to aid decision support systems in forestry preservation and coastal monitoring applications. Its swift evolution makes it a potential big player in remote sensing technologies today and in the near future.
Today's society is characterized by an abundant growth of data and information within the organizations, largely due to the extrapolation of Information and Communication Technologies (ICT) used to support their daily activities. The growing complexity of IS, has required the appearance of Information Systems Architectures (ISA) for their management and maintenance. The research team has identified relevance in its applicability within the Portuguese Higher Education Institutions (PHE), and a case study with the University of Tras-os-Montes and Alto Douro (UTAD) was drawn. Through the development and implementation of an ISA proposal, UTAD was provided with a transversal view of all the existing IS, allowing validation of the existence/need for IS aimed at managing information and decision-making under a multidimensional perspective, that is, oriented at different organizational levels, from the operational to the strategic level. Given the proposed ISA degree of abstraction, it can be applied to the other institutions within PHE, since they share similar contexts than the one inherent to UTAD.
The society and technologies evolution has resulted in a trend towards a growing amount of data stored by organizations and of the needs inherent to the analysis of that same data, in order to obtain information and knowledge generation. Based on this assumption it became critical to use new and more efficient technologies for processing that data in order to be able to get quality information in a timely manner. In order to meet the previously identified needs, various types of systems have emerged, whose features incorporate data processing functions and obtaining information for supporting decision-making processes. Examples of such systems are the DSS and the use of BI architectures. Given that currently many of the organizations services are supported by the existent IT infrastructure, it is necessary that these are suitable for the supporting the proper functioning of the available services. Assuming the previous concerns, the team inherent to this article assumed as very important to conceptualise a decision support system to address this adequate dimensioning of a University IT infrastructure. In order to achieve this goal, the Information and Communications Services (SIC) of the University of Trás-os-Montes e Alto Douro (UTAD) were used. Through the implementation of this decision support system, the SIC/UTAD improved their ability to make more informed and conscious decisions, thus optimizing and control more effectively the UTAD IT infrastructure.
1 October 2017 in International Journal of Technology and Human Interaction
Portuguese Higher Education Institutions have more and more data that needs to be processed in order to get information and, therefore, Knowledge. In order to respond to this need, over time there have been several types of IS supported by ICT, which enables them to achieve these features and, at the same time, help with their daily activities. However, the continuous evolution of this technological component has led to a current high degree of complexity, from which the Information Systems Architectures emerged as means of increasing the effectiveness of its management and maintenance. Using the University of Trás-os-Montes e Alto Douro as a case study, the research team proposed a generic ISA that enabled it to have a transversal vision of its IS, allowing the validation of existence/need IS focused on Information Management and decision-making under a multidimensional perspective, i.e., geared towards the various organizational levels, since the Operational level to the Strategic level, taking into account the information needs associated with each player.
In the last three decades with the Information Technologies advent and the growth of the concept of Virtual Environments, a set of new ways to perform tasks have emerged, in the most diversified areas of society. The main focus of this work was to verify if it was possible to increase the sense of presence through multi-sensory stimulation, creating a virtual environment of simulation that causes stress in exposure therapy, in this case in people who have a fear of heights. The evaluation of the sense of presence was made using the Portuguese version of a previously validated IPQ (Igroup Presence Questionnaire) and also through direct observation of the movements caused by oculomotor reflexes. Although the achievement results that were not very significant between the two tested groups, the multisensory simulation environment obtained better results in terms of involvement in relation to space and realism, which increased concentration in the experience. The obtained results seem to indicate that the alone addition of further stimuli does not lead to an increased feeling of presence, therefore existing the need to understand which are the critical stimuli for each assessment situation.