Abstract

Abstract
Unmanned Aerial Vehicles (UAVs) are being deployed in different applications due to their reduced time execution to perform tasks, more extensive coverage area, and more risk minimization to humans. In the Oil & Gas industry, its use for inspection activities is even more attractive due to the large structures in these facilities. Therefore, this research proposes deploying an autonomous UAV system to inspect unburied pipelines of onshore O&G facilities. The proposed UAV guiding system is based on image processing techniques Canny edge detection and Hough Transform to detect the line and on a path follower algorithm to generate the trajectory. The proposed strategy was developed in Robot Operating System (ROS) and tested in a simulated environment considering the practical oper-ational. The same controller was tested on a physical UAV to validate the results obtained in previous simulations. The results demonstrated the effectiveness and feasibility of deploying the proposed strategy for this specific task and the cost reduction potential for real-life operations, as well as reduced potential risks to the physical integrity of the workers.

Abstract
The increasing number of IoT devices and digital services offers cross-domain sensing and control opportunities to a growing set of stakeholders. The provision of cross-domain digital services requires interoperability as a key enabler to bridge domain specifics, while inferring knowledge and allowing new data-driven services. This work addresses H2020 InterConnect project's Interoperability Framework, highlighting the use of semantic web technologies. The interoperability framework layering is presented, particularly addressing the Semantic Interoperability layer as its cornerstone to build an interoperable ecosystem of cross-domain digital services via a federation of distributed knowledge bases. Departing from a generic, ontology-agnostic approach that can fit any cross-domain use case, it validates the approach by considering the SAREF family of ontologies, showcasing an IoT and energy cross-domain use case.

Abstract
The success of forest management towards achieving desired outcomes depends on various factors and can be improved through forest planning based on optimization approaches. Regardless of the owner type (state, private or common land) and/or governance model, the number of owners or management bodies considered in most studies is low, typically involving one owner/management body or a very small group. This study extends the approach of formulating a Forest Management Plan (FMP) to a large forest area, consisting of areas with different management bodies. The FMP model returns the harvest schedule that maximizes the volume of wood harvested during the planning horizon, while ensuring (1) sustainability and environmental constraints at the overall scale and (2) independent revenues for each management body. The FMP is tested in a real forested area, consisting of 22 common lands, governed by local communities for a planning period of 30 years. The results show that our approach is appropriate for several management bodies. When evaluating the impact of grouping areas (and their owner bodies) on the total volume removed, a comparison of the FMP model with an alternative model that allows for independent management (FMP-IND) showed significant differences, in terms of total volume removed at the end of the horizon. Global management leads to a reduction of about 8.6% in the total removed volume; however, it will ensure a heritage of well-diversified stands, in terms of age classes. The results highlight the importance of managing multi-stakeholder forest areas as a whole, instead of being managed independently, if the aim is to assure more sustainable management of forest resources in the mid and long term.

Abstract
Social networks are the main marketing entity of the hotel industry of the 21st century. To understand the impact that social networks have on the hotel sector, both from the point of view of the hotel and the consumer is becoming essential. The aim of this research is to find out how 5 stars Slovakian hotels present themselves in 3 different social networks Instagram, Facebook and Twitter and to compare them with each other. For that purpose a descriptive analyses of the most relevant features of this social networks was conducted. The study offers relevant insight for marketing practitioners in the hospitality industry

Abstract
Municipal Solid Waste Management Systems (MSWMS) worldwide are currently facing pressure due to the rapid growth of the population in cities. One of the biggest challenges in this system is the inefficient expenditure of time and fuel in waste collection. In this regard, cities/municipalities in charge of MSWMS could take advantage of information and communication technologies to improve the overall quality of their infrastructure. One particular strategy that has been explored and is showing interesting results is using a Wireless Sensors Network (WSN) to monitor waste levels in real-time and help decision-making regarding the need for collection. The WSN is equipped with sensing devices that should be carefully chosen considering the real scenario in which they will work. Therefore, in this work, three sets of sensors were studied to evaluate which is the best to be used in the future WSN assembled in Braganca, Portugal. Sets tested were HC-SR04 (S1), HC-SR04 + DHT11 (S2), and US-100 (S3). Tests considered for this work were air temperature and several distances. In the first, the performance of each set to measure a fixed target (metal and plastic box) was evaluated under different temperatures (1.7-37 degrees C). From these results, two best sets were further used to assess distance measurement at a fixed temperature. This test revealed low absolute errors measuring the distances of interest in this work, ranging from 0.18% to 1.27%.