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Publications

2021

Innovative Robot Design for Cleaning Solar Panels

Authors
Chellal, A; Lima, J; Pereira, AI; Costa, P;

Publication
PROCEEDINGS OF THE 11TH INTERNATIONAL CONFERENCE ON SIMULATION AND MODELING METHODOLOGIES, TECHNOLOGIES AND APPLICATIONS (SIMULTECH)

Abstract
The accumulation of dust particles on the solar panels decrease the total amount of solar energy received by the Photovoltaic panel (PV) and, it has also been proven that the increase of temperature reduces the overall efficiency. These effects have been studied by different researchers based on collected data comparison. As both of these parameters have a negative effect on the efficiency of the solar panel, it is essential to keep them clean and at low temperatures. The use of technologies, such as robots, is an effective way of carrying out repetitive tasks at low cost and in a short time. This work consists of developing a robot capable of cleaning and cooling the solar panels, based on images acquired through a camera positioned directly towards the panels, thus maintaining periodic cleaning in order to increase its efficiency. The preliminary results demonstrate the possibility of using this approach for the accomplishment of this task.

2021

Characterizing soft modes’ traveling in urban areas through indicators and simulated scenarios

Authors
Felicio, S; Hora, J; Maria Campos Ferreira, M; Dangelo, C; Costa, P; Abrantes, D; Silva, J; Coimbra, M; Teresa Galvão Dias, M;

Publication
Human Systems Engineering and Design (IHSED2021) Future Trends and Applications - AHFE International

Abstract
Nowadays, online route planners for soft modes are provided by several platforms such as Google Maps, OpenStreetMap, Here, or Waze. Itineraries are usually built using Shortest Path Problem algorithms that minimize the travel time or distance. In this work, we aim to identify and quantify the main features that influence itineraries’ choice by soft modes users in urban areas, able to support multi-objective routing, using simulated scenarios. We propose a set of 21 indicators, grouped into five dimensions: Safety-Security, Comfort, Air Quality, Accessibility and Time-Distance. Another contribution of this work is the simulation of scenarios to study soft modes’ multi-objective routing within urban areas.

2021

Adding Proof Calculi to Epistemic Logics with Structured Knowledge

Authors
Benevides, MRF; Madeira, A; Martins, MA;

Publication
Fundamentals of Software Engineering - 9th International Conference, FSEN 2021, Virtual Event, May 19-21, 2021, Revised Selected Papers

Abstract
Dynamic Epistemic Logic (DEL) is used in the analysis of a wide class of application scenarios involving multi-agents systems with local perceptions of information and knowledge. In its classical form, the knowledge of epistemic states is represented by sets of propositions. However, the complexity of the current systems, requires other richer structures, than sets of propositions, to represent knowledge on their epistemic states. Algebras, graphs or distributions are examples of useful structures for this end. Based on this observation, we introduced a parametric method to build dynamic epistemic logics on-demand, taking as parameter the specific knowledge representation framework (e.g., propositional, equational or even a modal logic) that better fits the problems in hand. In order to use the built logics in practices, tools support is needed. Based on this, we extended our previous method with a parametric construction of complete proof calculi. The complexity of the model checking and satisfiability problems for the achieved logics are provided. © 2021, IFIP International Federation for Information Processing.

2021

Preface

Authors
Huang Y.M.; Barroso J.; Sandnes F.E.; Chang C.C.; Rocha T.; Lai C.F.; Chen M.Y.;

Publication
Lecture Notes in Computer Science Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics

Abstract

2021

Analysis and Optimisation of a Production Line Using Discrete Simulation

Authors
Setti, FK; Geraldes, CAS; Almeida, JP; Trentin, MG;

Publication
Springer Proceedings in Mathematics and Statistics

Abstract
This study presents a simulation-based procedure to analyse a production line of a metalworking company. We use a simulation tool, ProModel ® software, to reproduce the existing production line layout of the company best-selling product which represents about 70% of the total sales. Our purpose is to get information about the existing system behaviour, and to find strategies to increase actual production level to meet the market’s demand. Based on an initial simulation model, different production scenarios were proposed and results have shown that it is possible to increase the production level allowing to meet the increasing demand for the product. The following changes in the production system were considered: (i) the use of intermediate stock of work-in-process items, (ii) the introduction of new equipment, and (iii) a mixed strategy where the introduction of new equipment is combined with the use of intermediate stock of work-in-process items. In summary, this research exhibits the flexibility of the simulation technique to address manufacturing problems throughout the creation of different scenarios providing some of the behaviour of the systems allowing the anticipation of final outputs. © 2021, Springer Nature Switzerland AG.

2021

Constraining the Nature of the PDS 70 Protoplanets with VLTI/GRAVITY*

Authors
Wang, JJ; Vigan, A; Lacour, S; Nowak, M; Stolker, T; De Rosa, RJ; Ginzburg, S; Gao, P; Abuter, R; Amorim, A; Asensio Torres, R; Baubock, M; Benisty, M; Berger, JP; Beust, H; Beuzit, JL; Blunt, S; Boccaletti, A; Bohn, A; Bonnefoy, M; Bonnet, H; Brandner, W; Cantalloube, F; Caselli, P; Charnay, B; Chauvin, G; Choquet, E; Christiaens, V; Clenet, Y; du Foresto, VC; Cridland, A; de Zeeuw, PT; Dembet, R; Dexter, J; Drescher, A; Duvert, G; Eckart, A; Eisenhauer, F; Facchini, S; Gao, F; Garcia, P; Lopez, RG; Gardner, T; Gendron, E; Genzel, R; Gillessen, S; Girard, J; Haubois, X; Heissel, G; Henning, T; Hinkley, S; Hippler, S; Horrobin, M; Houlle, M; Hubert, Z; Jimenez Rosales, A; Jocou, L; Kammerer, J; Keppler, M; Kervella, P; Meyer, M; Kreidberg, L; Lagrange, AM; Lapeyrere, V; Le Bouquin, JB; Lena, P; Lutz, D; Maire, AL; Menard, F; Merand, A; Molliere, P; Monnier, JD; Mouillet, D; Muller, A; Nasedkin, E; Ott, T; Otten, GPPL; Paladini, C; Paumard, T; Perraut, K; Perrin, G; Pfuhl, O; Pueyo, L; Rameau, J; Rodet, L; Rodriguez Coira, G; Rousset, G; Scheithauer, S; Shangguan, J; Shimizu, T; Stadler, J; Straub, O; Straubmeier, C; Sturm, E; Tacconi, LJ; van Dishoeck, EF; Vincent, F; von Fellenberg, SD; Ward Duong, K; Widmann, F; Wieprecht, E; Wiezorrek, E; Woillez, J;

Publication
ASTRONOMICAL JOURNAL

Abstract
We present K-band interferometric observations of the PDS 70 protoplanets along with their host star using VLTI/GRAVITY. We obtained K-band spectra and 100 mu as precision astrometry of both PDS 70 b and c in two epochs, as well as spatially resolving the hot inner disk around the star. Rejecting unstable orbits, we found a nonzero eccentricity for PDS 70 b of 0.17 0.06, a near-circular orbit for PDS 70 c, and an orbital configuration that is consistent with the planets migrating into a 2:1 mean motion resonance. Enforcing dynamical stability, we obtained a 95% upper limit on the mass of PDS 70 b of 10 M-Jup, while the mass of PDS 70 c was unconstrained. The GRAVITY K-band spectra rules out pure blackbody models for the photospheres of both planets. Instead, the models with the most support from the data are planetary atmospheres that are dusty, but the nature of the dust is unclear. Any circumplanetary dust around these planets is not well constrained by the planets' 1-5 mu m spectral energy distributions (SEDs) and requires longer wavelength data to probe with SED analysis. However with VLTI/GRAVITY, we made the first observations of a circumplanetary environment with sub-astronomical-unit spatial resolution, placing an upper limit of 0.3 au on the size of a bright disk around PDS 70 b.

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