ESTCB - Comunicações em encontros científicos e técnicos
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- 3D printing online learning environements: multiple approaches towards self-learning of engineering design studentsPublication . Pikkarainen, Ari; Gaspar, MarceloThis paper presents an exploratory study conducted at two Higher Education Engineering Schools, namely in the Lapland University of Applied Sciences (Finland) and in the Polytechnic Institute of Castelo Branco (Portugal), with the aim of constructing digital learning environments that promote increasing learning autonomy to students working with 3D printing technologies in engineering design. Based on pilot blended learning experiences carried-out in both schools, new instructional design solutions are proposed and discussed, aiming at a widespread use of such digital platforms not only for blended and online learning processes in engineering schools, but also as Massive Open Online Courses open to wider communities interested in such technologies.
- Accept mobile: a mobile tool for the SINMETRO accept information systemPublication . Caldeira, J.M.L.P.; Dias, Edgar; Paulo, Bruno; Neves, Paulo AlexandreIncreasing demand of mobile applications for on-site data acquisition pushes the development of flexible and easy to use mobile tools, with great advantages over the traditional computer-based approaches. The Accept System from SINMETRO allows data gathering for quality control, in the form of Inspection sheets. Such tool allows quality assurance by monitoring some samples of a given material, for instance milk, wine, and even maintenance management. This paper presents a mobile application in the Accept System that allows a Personal Digital Assistant (PDA) device to perform data gathering based on XML Inspection templates. Using .NET Compact Framework through C#, and database the technologies SQL Server and SQL Server CE, we developed Accept Mobile. Accept Mobile uses the Remote Data Access (RDA) mechanism to send data over to the server through a synchronization service, while also providing the needed support for disconnected operation. We prove that the mobile application is very convenient and provides enough functionality for the user to dismiss the portable computer, although the main application was never developed with mobility concerns in mind.
- Adaptive error control coding for a mobile broadband systemPublication . Torres, Paulo; Caseiro, Carlos; Gusmão, AntónioThe Mobile Broadband System (MBS) under research in Europoe aims at offering to mobile users an ATM-based radio access to the future integrated broadband communications network. It is well known that a high-quality transmission channel can be assumed within the fixed broadband network; however, this is far from being expected in the radio links of the future mobile system. This paper is concerned with the design of an error control coding scheme for a first stage of MBS implementation. The proposed scheme is a very flexible, hybrid one, which is based on the concatenation of a convolutional inner code, and a Reed-Solomon outer code, and combines ARQ and FEC features in an adaptive manner, under an implicit evaluation of the channel state. It is powerful enough to cope with poor channel conditions and is compatible with both ATM characteristics and those of a wide range of services (including required BER below lo-' with a delay of a few ms). A set of simulation results illustrates the advantages of the proposed error control coding scheme.
- Advanced optical modulation and format conversionPublication . Dionísio, Rogério Pais; Teixeira, António; Nogueira, RogérioOver the years, the increased search and exchange of information lead to an increase of traffic intensity in todays optical communication networks. Coherent communications, using the amplitude and phase of the signal, reappears as one of the transmission techniques to increase the spectral efficiency and throughput of optical channels. In this context, this paper present a survey on format conversion of modulated signals using MZI- SOAs, based exclusively on all-optical techniques through wavelength conversion. We also present two proposal using all-optical techniques: One for the conversion of amplitude modulation signals to a continuous phase modulation format, and another technique for the conversion of OOK signals to QPSK and QAM signals. Both approaches are experimentally validated.
- Affordable LTE network benchmarking based on transport fleetsPublication . Dionísio, Rogério Pais; Marques, Paulo; Marques, Hugo; Alves, Tiago Ferreira; Pereira, Luis Miguel Cardoso; Silva, Fernando; Ribeiro, Jorge Miguel AfonsoTo gain competitive advantage in today’s mobile market, cellular network testing, monitoring and improving customer experience is crucial. Today independent benchmarking companies are hired by mobile operators to run drive tests in a certain geographical areas. The high cost for running these tests results in a low frequency of execution, typically this benchmarking is executed no more than two or three times per year, which is not sufficient to follow the dynamics of an LTE network in a dense urban area. The majority of the drive testing costs come from the car, driver, and the in-car technician. Another approach is to take advantage of existing transportation companies to carry on network benchmarking services to Mobile Network Operators. Unattended measurement nodes can be deployed in existing transportation fleets without the need for dedicated field personnel, reducing the cost of testing up to 70%. This demo uses nodes placed in buses, available in several cities in Europe, to create and validate an automatic LTE network benchmark. The tool allows an easy comparative analyses of mobile network quality of Service and quality of experience parameters based on the operators raw data.
- All-optical phase modulation using MZI-SOAPublication . Reis, Cláudia; Dionísio, Rogério Pais; Neto, Berta; André, P.S.; Teixeira, AntónioThis paper experimentally demonstrate an all-optical phase modulation technique using both arms of a Mach-Zehnder interferometer structure with Semiconductor Optical Amplifiers (MZI-SOA), with NRZ modulated signals driven at 10 Gbit/s. The proposed optical phase modulator can be used in multi-level modulation signals generation, as an optical routing element, as well in optical code division multiple access transmission systems.
- All-optical XOR based on integrated MZI-SOA with Co and counter-propagation schemePublication . Reis, Cláudia; Dionísio, Rogério Pais; Neto, Berta; Teixeira, António; André, P.S.In this work we present a review of all-optical XOR gates based on Mach-Zehnder Interferometer with Semiconductor Optical Amplifiers (MZI-SOA), using NRZ modulated signals driven at 10 Gbit/s. The performance of two alternative schemes for logical XOR gates implementation is demonstrated through numerical simulations and experimentally. The extinction ratio shows high operation performance with low degradation.
- An approach using a low-code platform for retraining professionals to ICTPublication . Metrôlho, J.C.M.M.; Araújo, Ricardo; Ribeiro, Fernando Reinaldo; Castela, NunoInformation and Communications Technology is a growing area with a growing demand for employees. However, there is a shortage of professionals in this area and integrated strategies are required to foster the access of more people to these areas and provide training to develop the necessary skills. In this paper we present a short course that was designed to retrain unemployed people, mainly with already a higher education level in the area of the science technology engineering and math (STEM), to be Information and communications technology (ICT) professionals. After this training, trainees will have the opportunity to significantly increase the likelihood of being able to obtain employment in ICT areas. The course described involves public entities (including a higher education institution) and a private company, which is also a demonstration of synergies between academia and business. In the paper, the context that led to the appearance of the course, the fundamentals that supported the syllabus design, the partners involved, the objectives of the several subjects, the profile of the trainees and the results already achieved are described. To explain the fundamentals of the course syllabus we explain the most original features of the course regarding the usefulness of taking advantage of the abstraction allowed by the new low-code platforms, what seem to be appropriate and facilitator for retraining professionals from STEM to ICT. This approach, using a low code platform for retraining professionals to ICT, presents in our point of view, advantages over other approaches. In short, in the paper we intend to share the work done during the design and follow-up of the course, as well as the preliminary results obtained in the meantime.
- An autonomic system to characterize the physical and organizational context of public spacesPublication . Ribeiro, Fernando Reinaldo; Metrôlho, J.C.M.M.Traditionally, context-aware applications are developed using one of the following approaches: each application communicates directly with sources of context information; applications are developed with the aid of reusable libraries for processing context information or applications have their own context models. These approaches not only require effort on the part of those who develop them, but also create dependency between the developed context-aware applications and the systems developed for obtaining and providing the context information, thus hindering their reuse in other applications. In this paper we present a system that autonomously characterizes the physical, social and organizational context of a public space and delivers this information to context-aware applications. Experiments show that it provides relevant and useful context information that can be used by context-aware applications to improve their services.
- An industry 4.0 self description information model for software components contained in the administration shellPublication . Neto, Luís; Gonçalves, Gil; Torres, Pedro; Dionísio, Rogério Pais; Malhão, SérgioIndustry 4.0 is the movement towards a fourth industrial revolution that will consist in the digitization and integration of all value chain. In Europe, this movement is led by the German RAMI 4.0 (Reference Architecture for Industry 4.0) proposal, which is attracting a lot of attention from industry, academia and other practitioners. Under the RAMI 4.0 scope there is an Administration Shell proposal to abstract physical and logical assets in a standardized way. Once abstracted, assets become Industry 4.0 Components and can be fully integrated in the Cyber Physical Production System or value chain. This work focuses on the utilization of software components within the Administration Shell. There is a necessity to represent software components and their relation to industrial asset. Therefore, control and monitoring applications involving software components and other assets can be represented in compliance with the I4.0 Component Model. To address this necessity the Smart Object Self Description information model is proposed and applied to a real case study scenario.