Polytechnic Institute of Porto
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Engineering Education for Sustainable Development: The European Project Semester Approach
Full text linkContribution: An analysis of the extent to which sustainability is present in the syllabi, project briefs, report templates, and student final reports of the three Iberian European project semester (EPS) providers, over a five-year period. Background: EPS is a one-semester capstone project framework that adopts project-based learning and multicultural, multidisciplinary teamwork. Educating engineers for sustainable development requires fostering critical and ethical thinking and a desire for equity, solidarity and preservation of natural resources, and cultural and genetic diversity. Existing engineering capstone design programs emphasize solving real world problems, hands-on training, and soft skills, but few focus on sustainability aspects of engineering design. The three Iberian EPS providers adopt project-based learning and teamwork methodologies, promoting the development of transversal skills and addressing sustainability in a multicultural and multidisciplinary background. Intended Outcomes: To show that the three Iberian EPS providers follow these recommendations and contribute to raising students' awareness of sustainable development. Application Design: The proposed sustainability learning assessment method collects evidence from syllabi, project briefs, report templates, and final reports to extract faculty and student perspectives. The sustainability-related terms collected were processed into word cloud format, allowing a simple and intuitive interpretation of students' understanding of sustainability, and in co-occurrence network format, to understand if sustainability has a pervasive or confined presence within the reports. Findings: Iberian EPS faculty and students are aware of the social, economic, and environmental impact of their projects, in terms of quality of life, social responsibility, the use of resources, and environmentally friendly technology.info:eu-repo/semantics/publishedVersio
WiCAR - Simulating towards the Wireless Car
No full textDECSoS 2020 was held as part of the 39th International Conference on Computer Safety, Reliability and Security (SafeComp 2020).Part of the Lecture Notes in Computer Science book series (LNCS, volume 12235)Advanced driving assistance systems (ADAS) pose stringent requirements to a system’s control and communications, in terms of timeliness and reliability, hence, wireless communications have not been seriously considered a potential candidate for such deployments. However, recent developments in these technologies are supporting unprecedented levels of reliability and predictability. This can enable a new generation of ADAS systems with increased flexibility and the possibility of retrofitting older vehicles. However, to effectively test and validate these systems, there is a need for tools that can support the simulation of these complex communication infrastructures from the control and the networking perspective. This paper introduces a co-simulation framework that enables the simulation of an ADAS application scenario in these two fronts, analyzing the relationship between different vehicle dynamics and the delay required for the system to operate safely, exploring the performance limits of different wireless network configurations.info:eu-repo/semantics/publishedVersio
A model of integration ISO 9001 with Lean six sigma and main benefits achieved
No full textThe main purpose of this article is to depict the integration of Lean tools with requirements of ISO 9001:2015 standard as an operationalisation and support tool for a Quality Management System (QMS). The research was carried out through a questionnaire, which was sent to 2040 Portuguese companies. From the two hundred responses, 77 of them were validated (companies certified by at least one quality management system and which simultaneously have lean six sigma (LSS) tools and/or techniques implemented) corresponding to the sample of this study. Additionally, the research was also based on a case study in a footwear company where the model was applied. This research proposes a model for integrating Lean tools and requirements of ISO 9001:2015. This integration allows the QMS to become more practical and dynamic, reinforcing the creation of value for the organisation. As main benefits, we can highlight, among others: improvement of problem solving, waste reduction, improvement in internal communication, and increase in productivity. Thisarticle aims at becoming a relevant contribution to business management as it displays the main tools and methodologies to implement and sustain a QMS.This work has been supported by national funds through FCT (Fundação para a Ciência e Tecnologia)
through project UIDB/04728/2020.info:eu-repo/semantics/publishedVersio
Implementing Hybrid Semantics: From Functional to Imperative
No full textPart of the Lecture Notes in Computer Science book series (LNCS, volume 12545)Hybrid programs combine digital control with differential equations, and naturally appear in a wide range of application domains, from biology and control theory to real-time software engineering. The entanglement of discrete and continuous behaviour inherent to such programs goes beyond the established computer science foundations, producing challenges related to e.g. infinite iteration and combination of hybrid behaviour with other effects. A systematic treatment of hybridness as a dedicated computational effect has emerged recently. In particular, a generic idealized functional language HybCore with a sound and adequate operational semantics has been proposed. The latter semantics however did not provide hints to implementing HybCore as a runnable language, suitable for hybrid system simulation (e.g. the semantics features rules with uncountably many premises). We introduce an imperative counterpart of HybCore, whose semantics is simpler and runnable, and yet intimately related with the semantics of HybCore at the level of hybrid monads. We then establish a corresponding soundness and adequacy theorem. To attest that the resulting semantics can serve as a firm basis for the implementation of typical tools of programming oriented to the hybrid domain, we present a web-based prototype implementation to evaluate and inspect hybrid programs, in the spirit of GHCi for Haskell and UTop for OCaml. The major asset of our implementation is that it formally follows the operational semantic rules.info:eu-repo/semantics/publishedVersio
Hubs for VirtuosoNext: Online verification of real-time coordinators
No full textVirtuosoNext is a distributed real-time operating system (RTOS) fea- turing a generic programming model dubbed Interacting Entities. This pa- per focuses on these interactions, implemented as so-called Hubs. Hubs act as synchronisation and communication mechanisms between the application tasks and implement the services provided by the kernel. While the kernel provides the most basic services, each carefully designed, tested and opti- mised, tasks are limited to this handful of basic hubs, leaving the development of more complex mechanisms up to application specific implementations.
This work presents a toolset that supports the building of new services compositionally, using notions borrowed from the Reo coordination language, on which the developer can delegate coordination-related duties. This toolset uses a formal compositional semantics for hubs that captures dataflow and time, formalising the behaviour of existing hubs, and allowing the defini- tion of new ones. Furthermore, it enables the analysis and verification of hubs under our automata interpretation, including time-sensitive behaviour via the Uppaal model checker, usable on http://arcatools.org/hubs. We illustrate the proposed tools and methods by verifying key properties on different interaction scenarios between tasks and a composed hub.info:eu-repo/semantics/publishedVersio
Understanding the AC Equivalent Circuit Response of Ultrathin Cu(In,Ga)Se2 Solar Cells
No full textThis paper aims to study the ac electrical response of standard-thick, ultrathin, and passivated ultrathin Cu(In,Ga)Se 2 (CIGS) solar cells. Ultrathin CIGS is desired to reduce production costs of CIGS solar cells. Equivalent circuits for modeling the behavior of each type of solar cells in ac regime are based on admittance measurements. It is of the utmost importance to understand the ac electrical behavior of each device, as the electrical behavior of ultrathin and passivated ultrathin CIGS devices is yet to be fully understood. The analysis shows a simpler ac equivalent circuit for the ultrathin device without passivation layer, which might be explained by the lowered bulk recombination for thin-film CIGS solar cells when compared with reference thick ones. Moreover, it is observed an increase in shunt resistance for the passivated ultrathin device, which strengthens the importance of passivation for shunts mitigation when compared with unpassivated devices.info:eu-repo/semantics/publishedVersio
Tissue optical clearing as a diagnostic tool for tissue pathology differentiation
No full textWith the objective of developing a diagnostic tool, we have used the immersion optical clearing method and studied normal and pathological tissues (cancer, diabetes) under treatment by optical clearing agents (OCAs). In order to quantify pathology status OCA diffusion properties in different tissues were measured. We have demonstrated that free water content in cancerous tissues is higher than in normal.info:eu-repo/semantics/publishedVersio
Combining the tasklet model with OpenMP
No full textPaper presented at the 19th International Real-Time Ada Workshop 2018 (IRTAW)Previous workshops have discussed a proposal to augment Ada with fine-grained parallelism, based on the notion
of tasklets, a lightweight parallel entity. Recent works have shown the convergence of this model with the OpenMP
tasking model and have proposed their coexistence. In this paper we provide a status of the existent works, and
describe how these models could be combined.SIGADA ACM Special Interest Group on Ada Programming Languageinfo:eu-repo/semantics/publishedVersio
Dronemap Planner: A Service-Oriented Cloud-Based Management System for the Internet-of-Drones
No full textLow-cost Unmanned Aerial Vehicles (UAVs), also known as drones, are increasingly gaining interest for enabling novel commercial and civil Internet-of-Things (IoT) applications. However, there are still open challenges that restrain their real-world deployment. First, drones typically have limited wireless communication ranges with the ground stations preventing their control over large distances. Second, these low-cost aerial platforms have limited computation and energy resources preventing them from running heavy applications onboard. In this paper, we address this gap and we present Dronemap Planner (DP), a service-oriented cloud-based drone management system that controls, monitors and communicates with drones over the Internet. DP allows seamless communication with the drones over the Internet, which enables their control anywhere and anytime without restriction on distance. In addition, DP provides access to cloud computing resources for drones to offload heavy computations. It virtualizes the access to drones through Web services (SOAP and REST), schedules their missions, and promotes collaboration between drones. DP supports two communication protocols: (i.) the MAVLink protocol, which is a lightweight message marshaling protocol supported by commodities Ardupilot-based drones. (ii.) the ROSLink protocol, which is a communication protocol that we developed to integrate Robot Operating System (ROS)-enabled robots into the IoT. We present several applications and proof-of-concepts that were developed using DP. We demonstrate the effectiveness of DP through a performance evaluation study using a real drone for a real-time tracking application.info:eu-repo/semantics/publishedVersio
Radiative transitions in highly doped and compensated chalcopyrites and kesterites: The case of Cu2ZnSnS4
No full textThe theoretical models of radiative recombinations in both CuIn1−xGaxSe2 chalcopyrite and Cu2ZnSnS4 kesterite, and related compounds, were revised. For heavily doped materials, electrons are free or bound to large donor agglomerates which hinders the involvement of single donors in the radiative recombination channels. In this work, we investigated the temperature and excitation power dependencies of the photoluminescence of Cu2ZnSnS4-based solar cells in which the absorber layer was grown through sulphurization of multiperiod structuresofprecursorlayers.Forbothsamplestheluminescenceisdominatedbyanasymmetricbandwithpeak energy at∼1.22 eV, which is influenced by fluctuating potentials in both conduction and valence bands. A value of ∼60 meV was estimated for the root-mean-square depth of the tails in the conduction band. The radiative transitions involve the recombination of electrons captured by localized states in tails of the conduction band with holes localized in neighboring acceptors that follow the fluctuations in the valence band. The same acceptor level with an ionization energy of∼280 meV was identified in both absorber layers. The influence of fluctuating potentials in the electrical performance of the solar cells was discussedinfo:eu-repo/semantics/publishedVersio