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Publications

2019

Impact of different central path neighborhoods on gross error identification in State Estimation with generalized correntropy interior point method

Authors
Moayyed, H; Pesteh, S; Miranda, V; Pereira, J;

Publication
2019 2ND INTERNATIONAL CONFERENCE ON SMART ENERGY SYSTEMS AND TECHNOLOGIES (SEST 2019)

Abstract
Classical Weighted Least Squares (WLS) State estimation (SE) in power systems is known for not performing well in the presence of Gross Errors (GE). The alternative using Correntropy proved to be appealing in dealing with outliers. Now, a novel SE method, generalized correntropy interior point method (GCIP) is being proposed, taking advantage of the properties of the Generalized Correntropy and of the Interior Point Method (IPM) as solver. This paper discusses how the choice of different central path neighborhoods, an essential concept in IPM, is critical in the identification of gross errors. The simulation results indicate that a one-sided infinity norm neighborhood successfully identifies outliers in the SE problem, making GCIP a competitive method. © 2019 IEEE.

2019

Optimization of interrogation methods for sensors based on optical microbubble resonators

Authors
dos Santos, PSS; Coelho, L; Jorge, PAS;

Publication
FOURTH INTERNATIONAL CONFERENCE ON APPLICATIONS OF OPTICS AND PHOTONICS

Abstract
Optical microbubble resonators are among the highest sensitivity optical sensors. In the context of its application in the detection of water micro contaminants, in portable systems, their interrogation must be made by tracking the resonant wavelength peak position with the highest accuracy possible, at a reasonable cost. In this work different laser sources and scanning methods were tested and compared, aiming the development of a portable prototype. Each tunable laser source, was evaluated using a C2H2 Gas cell, which provided an absolute wavelength reference. Light transmitted through the cell was recorded using a photodetector and a software controlled feedback loop, enabling locking into selected reference peaks. Three distinct scanning methods were tested and compared for each laser source: large and short-range laser scanning and external waveform dithering, from which minimum standard deviations of 20, 0.18, and 0.07 pm, were obtained, respectively.

2019

Model-Based Testing of Post-WIMP Interactions Using Object Oriented Petri-Nets

Authors
Canny, A; Navarre, D; Campos, JC; Palanque, PA;

Publication
Formal Methods. FM 2019 International Workshops - Porto, Portugal, October 7-11, 2019, Revised Selected Papers, Part I

Abstract
Model-Based Testing (MBT) relies on models of a System Under Test (SUT) to derive test cases for said system. While Finite State Machine (FSM), workflow, etc. are widely used to derive test cases for WIMP applications (i.e. applications depending on 2D widgets such as menus and icons), these notations lack the expressive power to describe the interaction techniques and behaviors found in post-WIMP applications. In this paper, we aim at demonstrating that thanks to ICO, a formal notation for describing interactive systems, it is possible to generate test cases that go beyond the state of the art by addressing the MBT of advanced interaction techniques in post-WIMP applications. © Springer Nature Switzerland AG 2020.

2019

ns-3 NEXT: Towards a Reference Platform for Offline and Augmented Wireless Networking Experimentation

Authors
Fontes, H; Lamela, V; Campos, R; Ricardo, M;

Publication
Proceedings of the 2019 Workshop on ns-3, WNS3 2019, Florence, Italy, July 19-20, 2019.

Abstract
In the past years, INESC TEC has been working on using ns-3 to reduce the gap between Simulation and Experimentation. Two major contributions resulted from our work: 1) the Fast Prototyping development process, where the same ns-3 protocol model is used in a real experiment; 2) the Trace-based Simulation (TS) approach, where traces of radio link qualities and position of nodes from past experiments are injected into ns-3 to achieve repeatable and reproducible experiments. In this paper we present ns-3 NEXT, our vision for ns-3 to enable simulation and experimentation using the same platform. We envision ns-3 as the platform that can automatically learn from past experiments and improve its accuracy to a point where simulated resources can seamlessly replace real resources. At that point, ns-3 can either replace a real testbed accurately (Offline Experimentation) or add functionality and scale to testbeds (Augmented Experimentation). Towards this vision, we discuss the current limitations and propose a plan to overcome them collectively within the ns-3 community. © 2019 ACM.

2019

A Quantum Algorithm for Ray Casting using an Orthographic Camera

Authors
Alves, C; Santos, LP; Bashford Rogers, T;

Publication
PROCEEDINGS OF THE 2019 INTERNATIONAL CONFERENCE ON GRAPHICS AND INTERACTION (ICGI 2019)

Abstract
Quantum computing has the potential to provide solutions to many problems which are challenging or out of reach of classical computers. There are several problems in rendering which are amenable to being solved in quantum computers, but these have yet to be demonstrated in practice. This work takes a first step in applying quantum computing to one of the most fundamental operations in rendering: ray casting. This technique computes visibility between two points in a 3D model of the world which is described by a collection of geometric primitives. The algorithm returns, for a given ray, which primitive it intersects closest to its origin. Without a spatial acceleration structure, the classical complexity for this operation is O(N). In this paper, we propose an implementation of Grover's Algorithm (a quantum search algorithm) for ray casting. This provides a quadratic speed up allowing for visibility evaluation for unstructured primitives in O(root N). However, due to technological limitations associated with current quantum computers, in this work the geometrical setup is limited to rectangles and parallel rays (orthographic projection).

2019

Project Management Maturity: Case study analysis using OPM3 (R) model in manufacturing industry

Authors
Silva, R; Duarte, N; Barros, T; Fernandes, G;

Publication
2019 IEEE INTERNATIONAL CONFERENCE ON ENGINEERING, TECHNOLOGY AND INNOVATION (ICE/ITMC)

Abstract
This research analyses the degree of maturity of project management practices. The study object were the organizations that develop their main activity in manufacturing machines for the mining and quarrying and construction industries, in the region of Tamega e Sousa (Portugal). The theoretical background is the Organizational Project Management Maturity Model (OPM3 (R)). The methodological approach adopted was case study research (multiple case study). The results give us cues to believe that the degree of maturity of this industry is very low. The three companies analysed revealed levels of maturity around 15%. The reasons behind the low level of maturity are related with the lack of adoption of organizational enablers and the low level use of project management practices: 48% of project management processes are not used, and 28% are classified into an ad-hoc stage. In a management context this research can be a starting point to improve project management in organizations. Yet, one can conclude that these organizations develop their daily operations within a project management perspective but this is not recognized by them. Even identifying processes that are part of recognized good project management practices, these organizations score for a relatively low maturity level. This research brought important practical contributions, by raising at least awareness of the project management value in the organizations studied.

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