Polytechnic Institute of Porto
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BlockLoc: Secure Localization in the Internet-of-Things using Blockchain
No full textSeveral IoT applications are tightly dependent on the locations of the devices. However, localization algorithms can be easily compromised by injecting false locations. In this paper, we propose a Blockchain-based secure localization algorithm for the Internet of Things (IoT). The algorithm uses a public ledger (Blockchain) that contains nodes position and the list of their neighbor nodes. This ledger is shared among the IoT devices. Once an IoT device is localized its new position and the list of neighbor nodes are added to the Blockchain. This shared localization data will be used later by other IoT devices for their localization process. To avoid the attack where a malicious node sends a fake position, the correctness of the claimed position are verified before adding it to the Blockchain. Moreover, data exchanged between nodes (IoT devices) are signed to guarantee their authenticity and integrity. The integration of these security mechanisms into the localization process permits to exclude false data and therefore reduces the localization error. The simulation results show that adding the proposed security mechanism improves the localization accuracy of the algorithm when running in the presence of malicious nodes.info:eu-repo/semantics/publishedVersio
A Diagnostic Analysis of Absenteeism—A Case Study in a Portuguese Cork Industry
No full textAbsenteeism is defined as the absence of a worker from his or her workplace during a normal day’s work schedule and is seen as a problem which companies face every day. The absence of an employee can result in a significant drop in productivity and the company’s daily revenue can be negatively impacted by it, which when multiplied by the absence of multiple workers in different days can have a harmful impact on the company’s financial situation. However, most managers neither understand nor have looked into the causes of their absence issue. This study took place at a company which produces cork stoppers, which deals with a problem of high absenteeism that costs around 1,200,000€ per year to the company. The main goal of this study is to identify the sectors in this com- pany which have the highest percentage of absenteeism, quantify its impact on related outcomes and diagnose its causes. The results of this study show that most absenteeism occurs in production areas and the causes are related to musculo- skeletal problems. The consequences involve various costs to the company, some of them difficult to quantify.info:eu-repo/semantics/publishedVersio
How a CRM Tool Can Contribute to a Better Business Performance: The Case of a Shipping Company
No full textPart of the Lecture Notes in Electrical Engineering book series (LNEE, volume 505)Globalization is revolutionizing our way of living and the way business companies work. Technology is the reason for it, because it provides solutions that help the workers perform more effectively and efficiently and that allow for better execution. The development of relationships with the customer gives companies a better knowledge and understanding of their needs and leads to new strategies that aim at better results for the customer. Customer Relationship Management (CRM) tools are taken as important tools for this, since they help analyzing the companies’ Key Performance Indicators (KPIs). In this article we use the case of a shipping company in order to understand how such systems can contribute to such improvement. By analyzing the company’s CRM we suggest an adjustment to the business in order to get a better performance from it.We acknowledge the financial support of CIDEM, R&D unit funded by the
FCT – Portuguese Foundation for the Development of Science and Technology, Ministry of
Science, Technology and Higher Education, under the Project UID/EMS/0615/2016 and
UNIAG, R&D unit funded by the FCT – Portuguese Foundation for the Development of Science
and Technology, Ministry of Science, Technology and Higher Education, under the Project
UID/GES/04752/2016.info:eu-repo/semantics/publishedVersio
One Dimensional Trim Loss Decision Support Tool
No full textPart of the Lecture Notes in Electrical Engineering book series (LNEE, volume 505)The topic Cutting & Packing (C & P) has been published in many papers, and its importance within many industrial sectors is undeniable. For these reasons, several studies have been carried out on the optimization of the cutting process in order to improve the utilization of the useful area or the useful length of the raw material. Thus, this work aims to develop a computational tool that resolves the problem of minimizing losses in one-dimensional cuts. This problem is often encountered in industrial processes, where the beginning of the transformation and production of the raw material corresponds to the cutting process. To do so, the cutting problem will be formulated, and the Open Solver supplement will be used to obtain the solution.We acknowledge the financial support of CIDEM- Research Center of Mechanical Engineering, funded by FCT – Portuguese Foundation for the Development of Science and Technology, Ministry of Science, Technology and Higher Education, under the Project UID/EMS/0615/2016.info:eu-repo/semantics/publishedVersio
Blended learning and learner autonomy in higher education: a study with mechanical engineering students
Full text linkAs higher education faces the challenge of new and diverse demand, with more and non-traditional students enrolling in courses, it seems difficult to find a way to keep the standards as the funds decrease and the budget isn’t enough to hire new faculty.
A solution to this challenge is to use blended learning, combining online and in-class content and participation. This technology based model allows students to access resources at any time, according to their needs and constraints, such as work schedules. The faculty can monitor student access and work, and offer additional explanation when needed. On the other hand, as face-to-face classes decrease, and fewer contact hours are involved, it’s necessary to move fundamental knowledge acquisition out of the classroom and devote classroom time to applying, integrating and synthesizing the knowledge, allowing faculty to work with smaller groups. This means that a greater part of the teaching-learning transaction occurs away from schools and faculty, and that students have more control of their own learning, shifting from academic teaching staff to the learner, which fosters student-centred learning. Also, taking charge of one’s learning is a fundamental skill to lifelong learning, which has been recognized as an essential element of the European Higher Education Area. But, are all students ready to take charge of their own learning? Are all students able to take charge of their own learning?
Learner autonomy is the ability to take charge of one's own learning, as long as the learning environment provides opportunities for the learner to take control of their learning. In this study the relationship between students’ perception of their own learner autonomy and the willingness to learn in a blended learning environment will be investigated.info:eu-repo/semantics/publishedVersio
Learner autonomy in higher education: towards a validation of the PRO-SDLS scale to Portuguese engineering students
Full text linkLearner autonomy and self-direction in learning in higher education has become increasingly important as the focus changes from the teacher to the learner. Lifelong learning and the ability to continuously learn are only possible if students have more control of their own learning. This study is a first step towards an adaptation and validation of a Portuguese version of the Personal Responsibility Orientation to Self-Direction in Learning Scale (PRO-SDLS) to undergraduate engineering students. Using factor and reliability analysis, 12 items of the translated scale showed strong validity and reliability. The findings indicate that the PRO-SDLS can be used with engineering undergraduate students. More data collection and confirmatory analysis is suggested.info:eu-repo/semantics/publishedVersio
Adaptive Fuzzy Model-free Control For 3d Trajectory Tracking Of Quadrotor
No full textThis paper presents a novel adaptive control strategy with rejection ability for unmanned aerial vehicles (UAVs), namely fuzzy model-free control (FMFC). It is based on the model-free control (MFC) concept, where the control parameters are tuned online using fuzzy logic. The controller assumes an ultra-local model that can compensate unknown/unmodelled dynamics, uncertainties and external disturbances, ensuring a good robustness level. Moreover, the fuzzy logic system is used to tune online the proportional-derivative terms due to its heuristic aspect. These compensation and adaptation mechanisms allow ensuring good compromise robustness-performance even in the presence of disturbances. Several experiments, using RotorS Gazebo micro aerial vehicle (MAV) simulator, are provided to demonstrate the effectiveness of the proposed controller compared with other techniques. The fuzzy model-free controller shows superior performance without the time-consuming and tedious tuning task.info:eu-repo/semantics/publishedVersio
Controlling the operating conditions in an Operating Room
No full textIn this paper, we describe the development of a
module capable of controlling environmental conditions,
personnel movement and management of other important
parameters for an operating room (OR) or surgery block.
The base of assembly uses a real-life small scale model
trying to simulate the systematic functionality of an OR as
well as its crucial components. These include the regulation
of environmental parameters, logging of entries and exits by
the staff, management of pharmaceutical drugs and
diseases, and the statistical analysis of several acquired data.
The project integrates different types of technologies, such
as the microcontroller Arduino, a bidirectional
communication interface between this device and a
computer, a web based user interface for dynamic
interaction, as well as database concepts for data
management.info:eu-repo/semantics/publishedVersio
Chapter 6
No full textPlanning a thorough student assessment may produce good results in students’ learning. However, different aspects must be addressed in the course curriculum in order to foresee important features in the planning and implementation phases. This work presents the modifications carried out in a science course in engineering over three consecutive years, gradually incorporating important assessment to learn strategies identified in the literature. The results showed some crucial aspects of planning assessement in science/technology classes, in order to promote active learning and help students scaffold their knowledge. In accordance with teachers’ and students’ perceptions, some readjustments were made, creating a more demanding curriculum with positive learning and satisfaction outcomes.info:eu-repo/semantics/publishedVersio
Narrações multimodais: o que são e para que servem
No full textA melhoria da qualidade das aprendizagens na área das Ciências, Tecnologia, Engenharia e Matemática, necessita do aperfeiçoamento das práticas de ensino. Estas são em geral difíceis de estudar e aprimorar.
Este capítulo apresenta um instrumento que permite estudar em profundidade as práticas de ensino, do ponto de vista do professor, preservando a sua natureza holística, complexa e ecológica. Designámo-la de Narração Multimodal (NM). Neste capítulo apresenta-se o percurso da sua elaboração e explica-se o que são, como se fazem e para que podem ser usadas. As NM podem ser usadas por professores e investigadores com diversas finalidades específicas que globalmente contribuem para a melhoria da qualidade das aprendizagens.info:eu-repo/semantics/publishedVersio