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- Process Mining for IS Project Success Factors Management: A proposalPublication . Pedrosa, Joana; Varajão, João; Magalhaes, Luis Gonzaga; Martinho, RicardoResearch on Success Factors (SF) of Information Systems (IS) projects carried out over the last decades has resulted in a vast literature. However, extant studies typically aim to identify and list generic SF for projects, denoting a static perspective, with few concerns of practical nature regarding their use as management tools to support decisions throughout the projects’ lifecycle. On the other hand, process mining has been used to discover, analyze, and improve project management processes. In this paper, we propose a new approach that involves relating the performance of those processes with SF in IS projects. By using process mining, the aim is to automatically extract and manage SF in projects, measure processes performance, and provide project managers with information on how SF correlate with performance. This will provide managers with enhanced information regarding status and improvement opportunities for current and future projects. The main purpose is to contribute to the project management theory and practice by providing a decision support system that can associate performance with IS projects’ SF automatically obtained from internal and external data sources.
- Sustainability study of limestone quarry waste into value-added products: PCC and GCCPublication . Monteiro, S. M. C. S.; Jorge, Muanassa; Heleno, M. L.; Oliveira, N. S.; Alves, M. L.; Veiga, A.; Silva, A.Calcium carbonate can be obtained naturally from limestone, chalk, marble, and other sedimentary rock forms. Ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC) are two materials that can be produced from natural calcium carbonate. The future of GCC and PCC is promising since they are linked to industries with high demand, such as packaging, building & construction, transportation, and industrial applications, with an expected compound annual growth rate higher than 4% until 2027. This research focuses on the production of GCC and PCC through a comparative analysis that identifies the macro conditions that become advantageous to produce and commercialising PCC in a quarry context. This allows a valorisation of the limestone waste resulting from the extraction operations, converting it into by-products of the process. Not all existing limestone quarries in the Serra de Aire e Candeeiros region are suitable sources of raw material to produce PCC. The five extraction poles were identified with the potential for extracting suitable raw materials, associated with several companies dedicated to the extraction operation in these quarries.
- Qualitative analysis of the limestone waste potential from the Serra de Aire e Candeeiros quarriesPublication . Monteiro, S. M. C. S.; Jorge, Muanassa; Oliveira, N. S.; Alves, M.L.; Veiga, A.; Silva, A.The mountains of Aires and Candeeiros are part of the Maciço Calcário Estremenho where the landscape is predominantly made up of limestone. The limestone explored in the region has been the driver of social and cultural development, contributing significantly to the local economy. This emerging concern has motivated public and private organisations to develop solutions to improve the sector's sustainability. The present work aims to evaluate the limestone waste potential to produce precipitated (PCC) and ground (GCC) calcium carbonate in the region by surveying the local extraction industries that fulfil the defined minimum requirements to produce high quality PCC and GCC. The results allowed to stablish an estimate of the amount of waste resulting from the extraction process. The conversion of these wastes into PCC or GCC constitutes a possibility of recovery into by-products, allowing use in noble and profitable applications and contributing to the circular economy and the sustainability of the sector.
- Data Acquisition and Monitoring System for Legacy Injection MachinesPublication . Silva, Bruno; Sousa, João; Alenya, GuillemNowadays, companies must embrace the concept of Digitalization and Industry 4.0 to remain competitive in the market. The reality is that most of them do not have their industrial devices prepared to access their data on a real-time basis. As most companies do not have the possibility to renew all their legacy devices and because these devices are still very productive, a retrofit solution is of high interest. In this work, we propose an affordable procedure that allows data collection and monitoring of older injection machines, as a contribution towards legacy devices integration. The developed system neither requires additional proprietary modules, nor contractual annual fees for different devices, sharing the same interface across different machine manufacturers and also contributing to uniform data collection. Evaluation was carried out in a real shop floor, monitoring the injection parameters for different machine models, validating the effectiveness of the developed system.
- Smart Remote Control Design for SeniorsPublication . Pereira, António; Silva, Fernando; Ribeiro, José; Marcelino, Isabel; Barroso, JoãoTechnology is present in almost all aspects of our modern lives, and technological advances have been more and more prevalent. One would expect this to facilitate everybody’s life, rendering common tasks more practical and easier to perform, but that is often not the case - at least not for the elderly. Older people have significant difficulties in using technological equipment due to the visual, physical, cognitive and hearing limitations associated with the natural aging process; these aspects must be taken into account if the intention is that of integrating technology in the lives of the elderly. In order to improve the quality of life of the elderly, as well as to prevent their social isolation, a mobile device application was developed to act as an intelligent remote control. This mobile application deals with data from two different platforms that were previously developed for improving the quality of life of the senior population: HbbTV and +Social. The features built into this virtual remote control include the integration with the +Social platform, as well as a speech recognition mechanism, and the possibility of making and receiving video calls with an integrated contacts list. A comprehensive study was carried out, focusing on recommendations and rules for graphical interfaces for the elderly, so as to allow equipping the application with adequate usability standards. The most relevant result was the definition of a list of guidelines used to steer the development of the interface. An investigation of mechanisms and technologies for enabling the implementation of the required functionalities was also carried out in order to define methodologies for freeing the user from the need of possessing any level of computer literacy. A series of usability tests was also performed to validate the viability of the remote control application. These tests allowed assessing the quality of the application, especially concerning the Graphical User Interface, as well as to receive feedback from potential end users. Based on the data collected during the test phase we conclude that this product is useful and that it responds to a current need.
- Blind Guide: An Ultrasound Sensor-based Body Area Network for Guiding Blind PeoplePublication . Pereira, António; Nunes, Nelson; Vieira, Daniel; Costa, Nuno; Fernandes, Hugo; Barroso, JoãoWireless Sensor Networks, in particular Wireless Body Area Networks, is a technology suggested by the research community as allowing elderly people, or people with some kind of disability, to live in a safer, responsive and comfortable environment while at their homes. One of the most active threats to the autonomous life of blind people is the quantity and variety of obstacles they face while moving, whether they are obstacles in the footpath or obstacles coming out from the walls of buildings. Hence, it is necessary to develop a solution that helps or assists blind people while moving either in indoor or outdoor scenarios, simultaneously allowing the use of the use of white cane or the Seeing Eye dog. In this article, the authors propose the use of an ultra-sound based body area network for obstacle detection and warning as a complementary and effective solution for aiding blind people when moving from place to place. According to the cost estimates of the solution and to the negligible setup time, this could be a real effective complementary solution for blind people.
- Trajectory Generation for Robotic Additive Manufacturing: A Comparative StudyPublication . Cavalcanti, Marcella; Costelha, Hugo; Neves, CarlosThe integration of robot manipulators into additive manufacturing processes, particularly in fused filament fabrication, presents opportunities to overcome limitations of traditional three-axis systems. By leveraging the additional degrees of freedom, more versatile and efficient manufacturing solutions can be developed. However, this increased complexity introduces new challenges, including the need for trajectory planning that accounts for reachability, singularities, collision avoidance, and material deposition in various build orientations. This study focuses on the development and evaluation of trajectory generation approaches for robotic FFF using an ABB CRB 15000 manipulator. All approaches began with the same G-code input, and tests were conducted both in simulation and on the real robot. The results were analyzed in terms of trajectory accuracy, joint speed and acceleration profiles, parameters influence, and the Quality of the printed parts.
- An Evolutionary Algorithm based on an outranking relation for sorting problemsPublication . Oliveira, Eunice; Antunes, Carlos HenggelerA new approach for using the preferences elicited from a Decision Maker (DM) into the operational framework of an Evolutionary Algorithm (EA) is presented. The preference representation is achieved using the parameters and principles of the ELECTRE TRI method devoted to the sorting problem. The outranking relation is used to replace the non-dominance relation in the usual operators in the EA (crossover, mutation and selection operator). The aim of this approach is to focus the search on the region of interest defined by the DM's preferences and consequently restrict the number of solutions in the Pareto-optimal front to be subject to further screening. This aspect is particularly important when dealing with problems that lead to a large number of non-dominated solutions.
- A review on Robot-Assisted Additive Manufacturing Systems and TechnologiesPublication . Cavalcanti, M.; Costelha, Hugo; Neves, CarlosAbstract. The general use of robot manipulators in the Additive Manufacturing (AM) world could cause a paradigm shift on how these technologies are used today. Adding more degrees of freedom to the AM systems decreases the limita tions of current mainstream additive technologies, such as restricted build volume, high manufacturing times, and the use of support structures. However, existing traditional techniques for slicing 3D models and path planning generation do not translate smoothly into the requirements and constraints of robot manipulator systems. This paper presents a state-of-the-art review on the current systems and technologies, as well as advantages and challenges on the use of robot manipulators in AM, focusing on extrusion-based processes.
- Point Cloud Alignment for Deposited Material Assessment in Tunnel EnvironmentsPublication . Teixeira, Abel; Costelha, Hugo; Neves, Carlos; Bento, Luis CondeThe assessment of deposited material in tunnel reinforcement operations can be performed using a 3D model generated from multiple scans. For this purpose, an accurate alignment of the scanned models is required. Aligning existing structure model with data scanned after surface deformations can be challenging, particularly if reference markers are not available or were displaced. For scenarios where the surrounding structure is largely changed, certain procedures can be adapted when processing the scanned data to achieve consistent alignment between scanned and reference structure models. This work proposes a methodology to cope with these situations, analysing the impact of different approaches. Experiments were performed in a realistic scenario related with shotcrete of railway tunnels wall surfaces, with the results showing the applicability of the developed work. The proposed procedure relies in highlighting the importance of specific points that describe the same feature in the reference and aligning PC. The proposed methodology achieved an RMS difference of 0.0173 m, which lead to a drastic improvement in the point cloud alignment compared to the use of standard ICP algorithm without data preprocessing, which achieved 0.0518 m in the studied use-case.
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