956 resultados para polytechnic
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The emergence of smartphones with Wireless LAN (WiFi) network interfaces brought new challenges to application developers. The expected increase of users connectivity will impact their expectations for example on the performance of background applications. Unfortunately, the number and breadth of the studies on the new patterns of user mobility and connectivity that result from the emergence of smartphones is still insufficient to support this claim. This paper contributes with preliminary results on a large scale study of the usage pattern of about 49000 devices and 31000 users who accessed at least one access point of the eduroam WiFi network on the campuses of the Lisbon Polytechnic Institute. Results confirm that the increasing number of smartphones resulted in significant changes to the pattern of use, with impact on the amount of traffic and users connection time.
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European Master in Multimedia and Audiovisual Administration
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Engineering Education includes not only teaching theoretical fundamental concepts but also its verification during practical lessons in laboratories. The usual strategies to carry out this action are frequently based on Problem Based Learning, starting from a given state and proceeding forward to a target state. The possibility or the effectiveness of this procedure depends on previous states and if the present state was caused or resulted from earlier ones. This often happens in engineering education when the achieved results do not match the desired ones, e.g. when programming code is being developed or when the cause of the wrong behavior of an electronic circuit is being identified. It is thus important to also prepare students to proceed in the reverse way, i.e. given a start state generate the explanation or even the principles that underlie it. Later on, this sort of skills will be important. For instance, to a doctor making a patient?s story or to an engineer discovering the source of a malfunction. This learning methodology presents pedagogical advantages besides the enhanced preparation of students to their future work. The work presented on his document describes an automation project developed by a group of students in an engineering polytechnic school laboratory. The main objective was to improve the performance of a Braille machine. However, in a scenario of Reverse Problem-Based learning, students had first to discover and characterize the entire machine's function before being allowed (and being able) to propose a solution for the existing problem.
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Many learning problems require handling high dimensional datasets with a relatively small number of instances. Learning algorithms are thus confronted with the curse of dimensionality, and need to address it in order to be effective. Examples of these types of data include the bag-of-words representation in text classification problems and gene expression data for tumor detection/classification. Usually, among the high number of features characterizing the instances, many may be irrelevant (or even detrimental) for the learning tasks. It is thus clear that there is a need for adequate techniques for feature representation, reduction, and selection, to improve both the classification accuracy and the memory requirements. In this paper, we propose combined unsupervised feature discretization and feature selection techniques, suitable for medium and high-dimensional datasets. The experimental results on several standard datasets, with both sparse and dense features, show the efficiency of the proposed techniques as well as improvements over previous related techniques.
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Feature selection is a central problem in machine learning and pattern recognition. On large datasets (in terms of dimension and/or number of instances), using search-based or wrapper techniques can be cornputationally prohibitive. Moreover, many filter methods based on relevance/redundancy assessment also take a prohibitively long time on high-dimensional. datasets. In this paper, we propose efficient unsupervised and supervised feature selection/ranking filters for high-dimensional datasets. These methods use low-complexity relevance and redundancy criteria, applicable to supervised, semi-supervised, and unsupervised learning, being able to act as pre-processors for computationally intensive methods to focus their attention on smaller subsets of promising features. The experimental results, with up to 10(5) features, show the time efficiency of our methods, with lower generalization error than state-of-the-art techniques, while being dramatically simpler and faster.
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This work describes the impact of different teachers’ approaches in using Moodle, for supporting their courses, at the Polytechnic of Porto - School of Engineering. The study covers five different courses, from different degrees and different years, and includes a number of Moodle resources especially supporting laboratory classes. These and other active resources are particularly analyzed in order to evaluate students’ adherence to them. One particular course includes a number of remote experiments, made available through VISIR (Virtual Instrument Systems in Reality) and directly accessible through links included in the Moodle course page. The collected data have been correlated with students’ classifications in the lab component and in the exam, each one weighting 50% of their final marks. This analysis benefited from the existence of different teachers’ approaches, which resulted in a diversity of Moodle-supported environments. Conclusions point to the existence of a positive correlation factor between the number of Moodle accesses and the final exam grade, although the quality of the resources made available by the teachers seems to be preponderant over its quantity. In addition, different students perspectives were found regarding active resources: while some seem to encourage students to participate (for instance online quiz or online reports), others, more demanding, are unable to stimulate the majority of them.
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This work extends a recent comparative study covering four different courses lectured at the Polytechnic of Porto - School of Engineering, in respect to the usage of a particular Learning Management System, i.e. Moodle, and its impact on students' results. A fifth course, which includes a number of resources especially supporting laboratory classes, is now added to the analysis. This particular course includes a number of remote experiments, made available through VISIR (Virtual Instrument Systems in Reality) and directly accessible through links included in the Moodle course page. We have analyzed the students' behavior in following these links and in effectively running experiments in VISIR (and also using other lab related resources, in Moodle). This data have been correlated with students' classifications in the lab component and in the exam, each one weighting 50% of their final marks. We aimed to compare students' performance in a richly Moodle-supported environment (with lab component) and in a poorly Moodle-supported environment (with only theoretical component). This question followed from conclusions drawn in the above referred comparative study, where it was shown that even though a positive correlation factor existed between the number of Moodle accesses and the final exam grade obtained by each student, its explanation behind was not straightforward, as the quality of the resources was preponderant over its quantity.
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In this paper, we study an international market model in which the home government imposes a tariff on the imported goods. The model has two stages. In the first stage, the home government chooses an import tariff to maximize a function that cares about the home firm’s profit and the total revenue. Then, the firms engage in a Cournot or in a Stackelberg competition. We compare the results obtained in the three different ways of moving on the decision make of the firms.
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In this paper, we study the effects of environmental and trade policies in an international mixed duopoly serving two markets, in which the public firm maximizes the sum of consumer surplus and its profit. We also analyse the effects of privatization. The model has two stages. In the first stage, governments choose environmental taxes and import tariffs, simultaneously. Then, the firms engage in a Cournot competition, choosing output levels for the domestic market and to export. We compare the results obtained in the three different ways of moving on the decision make of the firms.
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This paper analyses the effects of tariffs on an international economy with a monopolistic sector with two firms, located in two countries, each one producing a homogeneous good for both home consumption and export to the other identical country. We consider a game among governments and firms. First, the government imposes a tariff on imports and then we consider the two types of moving: simultaneous (Cournot-type model) and sequential (Stackelberg-type model) decisions by the firms. We also compare the results obtained in each model.
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In this paper, we study the effects of environmental and privatization in a mixed duopoly, in which the public firm aims to maximize the social welfare. The model has two stages. In the first stage, the government sets the environmental tax. Then, the firms engage in a Cournot competition, choosing output and pollution abatement levels.
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Tese de Doutoramento
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Engineering education practices have evolved not only due to the natural changes in the contents of the curricula and skills but also, and more recently, due to the requirements imposed by the Bologna revision process. In addition, industry is becoming more demanding, as society is becoming more and more aware of the global needs and consequences of industrial practices. Under this scope, higher education needs not only to follow but also to lead these trends. Therefore, the School of Engineering of the Polytechnic Institute of Porto (ISEP), a Global Reporting Initiative (GRI) training partner in Portugal, prepared and presented its Sustainability Action Plan (PASUS), with the main objective of creating a new kind of engineers, with Sustainable Development at the core of their graduation and MsC degrees. In this paper, the main strategies and activities of the referred plan along with the strategic approach, which guided its development and implementation, will be presented in detail. Additionally, a reflection about the above mentioned bridge between concept and application will be established and justified, in the framework of the action plan. Although in most of the situations, there was no prior discussion or specific request, many of the graduation and post-graduation programmes offered by ISEP already include courses that attend to PASUS philosophy. As a consequence, the number of Master thesis, Graduation projects and R&D projects that address sustainability problems has grown substantially, a proof that for ISEP community, sustainability really matters!
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The Polytechnic Institute of Oporto (IPP), which has a solid history of online education and innovation through the use of technology, has been particularly interested and focused on Massive Open Online Courses (MOOC) developments. The aim of this paper is to present the whole process from initial discussions to completion of the “Mathematics Without Limits” MOOC Project that exists in IPP and also to contribute for a change in the way as teaching and learning Mathematics is seen and practiced nowadays. In 2013, IPP developed its own platform, which gave us the opportunity to explore new educational techniques as a pedagogical resource as well as to enhance students’ motivation, through a set of interactive materials at their disposal, totally adapted to their needs. Students lack of motivation is mainly justified by their weak Math preparation, poor consolidated basis on the subject and different backgrounds of the students. To tackle this issue and based on our Math online courses teaching experience, we decided to create short duration MOOC, expecting to aid retention of students and also to reverse the path of students giving up on Math by giving them a friendly way of managing their own learning commitment. We also think that this MOOC will be a good approach to level out some math skills among freshmen.
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The Polytechnic Institute of Oporto (IPP), which has a solid history of online education and innovation through the use of technology, has been particularly interested and focused on Massive Open Online Courses (MOOC) developments. The aim of this paper is to present the whole process from initial discussions to completion of the “Mathematics Without Limits” MOOC Project that exists in IPP and also to contribute for a change in the way as teaching and learning Mathematics is seen and practiced nowadays. In 2013, IPP developed its own platform, which gave us the opportunity to explore new educational techniques as a pedagogical resource as well as to enhance students’ motivation, through a set of interactive materials at their disposal, totally adapted to their needs. Students lack of motivation is mainly justified by their weak Math preparation, poor consolidated basis on the subject and different backgrounds of the students. To tackle this issue and based on our Math online courses teaching experience, we decided to create short duration MOOC, expecting to aid retention of students and also to reverse the path of students giving up on Math by giving them a friendly way of managing their own learning commitment. We also think that this MOOC will be a good approach to level out some math skills among freshmen.