2019
Autores
Moreira, MJ; Garcia Diez, J; de Almeida, JMMM; Saraiva, C;
Publicação
INTERNATIONAL JOURNAL OF CONSUMER STUDIES
Abstract
Food labelling is a means of communication between food business operators and consumers, representing an important factor in consumer purchasing decisions. The enforcement of the new food labelling policy is aimed to improve food safety and public health through the mandatory indication of information and nutritional values. To understand the usefulness of the information provided for consumers, a survey was carried out to assess the efficacy of the information presented in food labelling. Principal component analysis was performed to obtain a smaller number of uncorrelated factors regarding the usefulness of food labelling. Results showed consumers usually do not read food labels due to lack of time and excessive information. Additionally, food labelling was observed to be more useful for specific consumer groups, such as, athletes, consumers with health conditions or consumers concerned with a healthy lifestyle. The results of the present study highlight the need of information campaigns by public health authorities to show the importance and advantages of reading food labels as well as the development of essential information which should be quickly and clearly seen and understood by consumers.
2019
Autores
Gusmão, P; Almeida, T; Lopes, F; Muryn, Y; Martins, J; Au Yong Oliveira, M;
Publicação
Advances in Intelligent Systems and Computing
Abstract
Microtransactions dominate today’s video game industry and will continue to do so for the foreseeable future, despite all the controversy it brings. To approach this problem, we created a survey, shared it on several gaming forums (a total of 1661 answers were obtained), then we designed a theoretical model and based on that, an automatic analysis was performed to understand what microtransactions are adequate to certain types of videogames. In parallel, we also performed a manual analysis that helped us gain insights into player preferences. Through the manual analysis we can conclude that players show a greater tendency to spend on microtransactions in mobile games. On average, respondents spend more on microtransactions than on purchasing videogames per month; with this, we can understand why the market of microtransactions has been growing greatly in recent years. Players that have jobs spend more on time savers microtransactions, and this probably happens because of the lack of time these players have comparing to the rest and the fact that they have an income to spend. Players aged 25 and above have shown to be more inclined to spend money to remove advertisements from games; however, players under the age of 25 are more inclined to spend money on general microtransactions in contrast to their older counterparts. It is also noticeable the negative sentiment towards players that spend money on advantageous items. © Springer Nature Switzerland AG 2019.
2019
Autores
Pereira Cunha, PM; Leal, JP;
Publicação
8th Symposium on Languages, Applications and Technologies, SLATE 2019, June 27-28, 2019, Coimbra, Portugal.
Abstract
Quarmic is a web framework for rapid prototyping of web applications. Its main goal is to facilitate the development of web applications by providing a high level of abstraction that hides Web communication complexities. This framework allows developers to build scalable applications capable of handling data communication in different models, data persistence and authentication, requiring them just to use simple annotations. Quarmic’s approach consists of the replication of the shared object among clients and server in order to communicate through its methods execution. Where the annotations, namely decorators, are used to indicate the concern (model or view) that each method addresses and to implement the framework’s inversion of control. By indicating the method concern, it enables the separation of its execution across the clients (responsible for the view) and the server (responsible for the model) which facilitates the state management and code maintenance. © Pedro M. P. Cunha and José P. Leal.
2019
Autores
Oliveira, J; Renna, F; Coimbra, M;
Publicação
IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING
Abstract
The analysis of heart sounds is a challenging task, due to the quick temporal onset between successive events and the fact that an important fraction of the information carried by phonocardiogram (PCG) signals lies in the inaudible part of the human spectrum. For these reasons, computer-aided analysis of the PCG can dramatically improve the quantity of information recovered from such signals. In this paper, a hidden semi-Markov model (HSMM) is used to automatically segment PCG signals. In the proposed models, the emission probability distributions are approximated via Gaussian mixture model (GMM) priors. The choice of GMM emission probability distributions allow to apply re-estimation routines to automatically adjust the HSMM emission probability distributions to each subject. Building on the proposed method for fine tuning emission distributions, a novel subject-driven unsupervised heart sound segmentation algorithm is proposed and validated over the publicly available PhysioNet dataset. Perhaps surprisingly, the proposed unsupervised method achieved results in line with state-of-the-art supervised approaches, when applied to long heart sounds.
2019
Autores
Melo, P; Pereira, M; Araujo, RE;
Publicação
45TH ANNUAL CONFERENCE OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY (IECON 2019)
Abstract
Switched reluctance machines (SRM) are simple, robust and fault tolerant machines, usually operating under strong nonlinear characteristics. Most SRM models address magnetic saturation, but hysteresis effect is usually disregarded. This paper is based on a developed four-quadrant SRM drive simulation model, where magnetization characteristics are generated through the original Jiles-Atherton (J-A) hysteresis model. The main goal is to investigate the hysteresis impact on the SRM drive controller performance. Steady-state operation scenarios are simulated and compared. For the adopted current control strategy (PWM), the results show a significant impact in all drive components, particularly for low speed with high load operation.
2019
Autores
Barros, N; Carvalho, M; Silva, C; Fontes, T; Prata, JC; Sousa, A; Manso, MC;
Publicação
JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A-CURRENT ISSUES
Abstract
The volatile organic compounds benzene, toluene, ethylbenzene, and xylene (BTEX) are emitted into the atmosphere at gas stations (GS) leading to chronic exposure of nearby residents, which raises public health concerns. This study aimes at determining the contribution of GS emissions to BTEX exposure in nearby residents. Three Control and Exposed areas to BTEX emissions from GS were defined in a medium-sized European city (Porto, Portugal). BTEX atmospheric levels were determined in Control and Exposed areas using passive samplers deployed outdoors (n = 48) and indoors (n = 36), and human exposure was estimated for 119 non-smoking residents using the first urine of the day. Results showed that median BTEX outdoor and indoor concentrations were significantly higher for Exposed than Control areas, with exception of ethylbenzene and xylene indoor concentrations, where no marked differences were found. Comparison of urinary concentrations between Exposed and Control residents demonstrated no significant differences for benzene and ethylbenzene, whereas levels of toluene and xylene were significantly higher in Exposed residents. No marked correlation was obtained between atmospheric BTEX concentrations and urinary concentrations. Data indicate the potential impact on air quality of BTEX emissions from GS, which confirms the importance of these findings in urban planning in order to minimize the impact on health and well-being of surrounding populations.
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