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Publications

2016

Towards a Formal Validation of ETL Patterns Behaviour

Authors
Oliveira, B; Belo, O; Macedo, N;

Publication
Model and Data Engineering

Abstract
The development of ETL systems has been the target of many research efforts to support its development and implementation. In the last few years, we presented a pattern-oriented approach to develop these systems. Basically, patterns are comprised by a set of abstract components that can be configured to enable its instantiation for specific scenarios. Even when using high-level components, the ETL systems are very specific processes that represent complex data requirements and transformation routines. Several operational requirements need to be configured and system correctness is hard to validate, which can result in several implementation problems. In this paper, a set of formal specifications in Alloy is presented to express the structural constraints and behaviour of a slowly changing dimension pattern. Then, specific physical models can be generated based on formal specifications and constraints defined in an Alloy model, helping to ensure the correctness of the configuration provided.

2016

THE SOCIAL REPRESENTATIONS OF (GREEN) CHEMISTRY AND ROBOTICS AMONG TEENAGERS: AN EXPLORATORY STUDY

Authors
Moreira, L; Vieira, H; Morais, C; Sousa, A; Costa, H; Paiva, JC;

Publication
EDULEARN16: 8TH INTERNATIONAL CONFERENCE ON EDUCATION AND NEW LEARNING TECHNOLOGIES

Abstract
The purpose of the research is to identify the most common social representations of chemistry, green chemistry, robotics and sustainability among teenagers as they were engaging in a project that links robotics and green chemistry. Subjects were students from a school in the north of Portugal enrolled in year 9 (n = 163, 73 males and 86 females, 4 missing values, mean age around 15 years-old). Data was collected through a questionnaire that consisted of four open-ended, free association questions. Participants were asked to express their ideas and thoughts on each one of the four mentioned stimuli and asked to draw a robot. Written responses and drawings of robots were submitted to a content analysis. Preliminary results showed that the ten most frequent words associated with chemistry explain around 49% of the semantic field (average of 4.5 words per participant) and largely consist of conceptual elements, e.g., atoms (38), protons (22) and ions (22), experiments (114), laboratory (62) and explosions (19). The ten most frequent words associated with green chemistry explain around 42% of the semantic field of the representation. Participants - which never have learnt about green chemistry at school curriculum - filled their representations (2.8 words per participant) with elements derived from environment (e.g., nature, environment, trees,...). Only 92 participants defined sustainability, many of them associating the concept with earth's natural resources and future. The ten most frequent words associated with robotics (4.1 words per participant) explain around 53% of the semantic field which consists of robots (129), technology (50), electricity (39), metal (33), energy (20), circuits (18) and computers (17): electronics rather than informatics contribute for the representation. Most of the drawings of robots were anthropomorphic resembling more C-3PO than R2-D2 from Star Wars movies. Human elements, such as eyes, mouth and hands are largely present while movement is assured by means of feet or wheels. The significance of the study is that there is a decalage between science and technology developments and teenager audience understanding. From the point of view of the theory of social representations, this gap is not only expected but also understandable. Popular culture although still inspire the representation of chemistry is not as relevant as it would be if participants have not attended physics and chemistry classes for three years. On the other hand, since green chemistry and robotics are not included in the ordinary curriculum until year 9, the concepts are at loose and their meaning must be grounded elsewhere. Despite the impressive and rapid changes that characterize the technology research, its market and advertising, old metaphors and symbols still contribute to build the representations of teenagers about robotics while green chemistry - a relatively new approach - has its poor semantic field rooted in chemistry and environment. School, thus, must act as a medium to help students to build a coherent worldview that is capable of copying with contemporary challenges, strongly affected by science and technology namely regarding sustainability. An ongoing project is designed to introduce green chemistry experiments that involve slow reactions via a programmable robotic arm in the school laboratory to conduct. The planned activities include monitoring experiences by students at home by means of a live webcam.

2016

Sublimation-like behavior of cardiac dynamics in heart failure: A malignant phase transition?

Authors
Goldberger, AL; Henriques, TS; Mariani, S;

Publication
Complexity

Abstract
An abrupt transition from sinus rhythm to atrial fibrillation (AF) is common in patients with chronic heart failure (CHF). We propose a conceptual framework for viewing this malignant transition in terms of a type of sublimation marked by the switch from highly periodic sinus interbeat interval dynamics characteristic of CHF to a state of random disorganization with AF. Sublimation of physical substances involves an increase in entropy via heat transfer. In contrast, the disease-related sublimation-like behavior involves a loss of information content, associated decreases in cardiac bioenergetic capacity and in multiscale entropy. © 2016 Wiley Periodicals, Inc. Complexity 21: 24–32, 2016. © 2016 Wiley Periodicals, Inc.

2016

Control and Management Architectures

Authors
Matos, MA; Seca, L; Madureira, AG; Soares, FJ; Bessa, RJ; Pereira, J; Peças Lopes, J;

Publication
Smart Grid Handbook

Abstract

2016

Increasing the Reach of Enterprises through Electronic Commerce: A Focus Group Study Aimed at the Cases of Portugal and Spain

Authors
Goncalves, R; Martins, J; Branco, F; Perez Cota, M; Oliveira, MAY;

Publication
COMPUTER SCIENCE AND INFORMATION SYSTEMS

Abstract
E-commerce notably increases the reach of enterprises, bringing a firm's products and services into the international arena. In times of shrinking domestic markets, due to national crises, becoming available in global markets is essential for survival and growth. We have thus held three focus group interactions to produce a set of strategic recommendations with regards to how to improve e-Commerce adoption levels in Iberian enterprises, essential in times of local hardship and market contraction. Suggestions include creating actions to influence governments to re-evaluate the legislation that regulates e-Commerce, making it more transparent; encouraging venture capitalists, banks and business angels to finance such e-Commerce endeavors; encouraging higher education institutions (HEI) to partner with Iberian enterprises to ensure knowledge transfer in both directions; creating, with HEI and training organizations, a set of new training courses directed at Iberian enterprises and focusing on concepts such as Web 2.0 capabilities and a coherent online organizational identity. Fundamental is the perspective that e-Commerce is a strategic issue, warranting funds and qualified personnel, at different levels in the hierarchy, for adequate strategic e intent, e-vision, and e-mission formulation, followed by effective e-process implementation.

2016

The use of artificial intelligence for the prediction of productivity parameters in swine culture

Authors
Sangoi, LF; Kessler, AM; Neuenfeldt Júnior, AL; Siluk, JCM; Ribeiro, AML; Soliman, M;

Publication
Pesquisa Operacional

Abstract
In similar conditions of food handling and genetics, there are large differences in the final productivity of farms, resulting from inherent factors of the production system. This fact predisposes the need of studies on optimizing the rearing conditions of the farms, in order to verify the main limitations for the producers. Therefore, the present study aims to generate predictions of the swine productivity in the finishing phase, using variables related to their profiles and the production results achieved. 107 farmers belonging to a swine cooperative were considered in the study, located in 47 counties at the Taquari valley region, Brazil. Predictions were generated through the aid of neural networks, and the findings show that Artificial Neural Networks (ANN) can predict the productivity variables Feed Conversion, Mortality and Average Daily Gain for the proposed case. © 2016 Brazilian Operations Research Society.

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