2015
Autores
Morris T.; Basden A.; Buey T.; Chemla F.; Conan J.M.; Correia C.; Dohlen K.; Fusco T.; Gendron E.; Gratadour D.; Jagourel P.; Myers R.; Neichel B.; Petit C.; Rees P.; Rousset G.;
Publicação
Adaptive Optics for Extremely Large Telescopes 4 - Conference Proceedings
Abstract
MOSAIC is the proposed multiple object spectrograph for the E-ELT that will eventually combine two AO observing modes within a single instrument. MOSAIC will contain up to 20 open-loop multiple object AO channels feeding NIR IFUs in addition to up to 200 seeing-limited (or GLAO corrected) VIS - NIR fibre pickoffs. Wavefront tomography will be implemented using a combination of LGS and a few high-order NGS distributed across the field with the wavefront correction applied in a split open/closed loop configuration. MOSAIC will be the only E-ELT instrument planned that can utilize the full 10 arcminute diameter field of view, enabling highly efficient observing modes for this workhorse instrument. Use of the full E-ELT field inevitably requires a closer integration between the telescope control system and the instrument AO systems, however this can bring several potential benefits to overall system performance. Here we present the initial design concept and baseline performance of the MOSAIC instrument and AO system(s) taking advantage of the CANARY on-sky results and inheriting from the previous Phase A study of EAGLE. Finally, we will highlight areas of system performance and calibration that will require further analysis and trade-off during the course of the upcoming Phase A study.
2015
Autores
Lucas A.; Bonavitacola F.; Kotsakis E.; Fulli G.;
Publicação
Electric Power Systems Research
Abstract
Fast charging is perceived by users as a preferred method for extending the average daily mobility of electric vehicles (EV). The rated power of fast chargers, their expected operation during peak hours, and clustering in designated stations, raise significant concerns. On one hand it raises concerns about standard requirements for power quality, especially harmonic distortion due to the use of power electronics connecting to high loads, typically ranging from 18 to 24 kW h. On the other hand, infrastructure dimensioning and design limitations for those investing in such facilities need to be considered. Four sets of measurements were performed during the complete charging cycle of an EV, and individual harmonic's amplitude and phase angles behaviour were analysed. In addition, the voltage and current total harmonic distortion (THD) and Total Demand Distortion (TDD) were calculated and the results compared with the IEEE519, IEC 61000/EN50160 standards. Additionally, two vehicles being fast charged while connected to the same feeder were simulated and an analysis was carried out on how the harmonic phase angles would relate. The study concluded that the use of TDD was a better indicator than THD, since the former uses the maximum current (IL) and the latter uses the fundamental current, sometimes misleading conclusions, hence it is suggested it should be included in IEC/EN standard updates. Voltage THD and TDD for the charger analysed, were within the standard's limits of 1.2% and 12% respectively, however individual harmonics (11th and 13th) failed to comply with the 5.5% limit in IEEE 519 (5% and 3% respectively in IEC61000). Phase angles tended to have preferential range differences from the fundamental wave. It was found that the average difference between the same harmonic order phase angles was lower than 90°, meaning that when more than one vehicle is connected to the same feeder the amplitudes will add. Since the limits are dependable on the upstream short circuit current (ISC), if the number of vehicles increases (i.e. IL), the standard limits will decrease and eventually be exceeded. The harmonic limitation is hence the primary binding condition, certainly before the power limitation. The initial limit to the number of chargers is not the power capacity of the upstream power circuit but the harmonic limits for electricity pollution.
2015
Autores
Leal, J; Couto, R; Costa, PM; Galvao, T;
Publicação
2015 IEEE 18TH INTERNATIONAL CONFERENCE ON INTELLIGENT TRANSPORTATION SYSTEMS
Abstract
There is a growing interest in integrating public transportation with the smartphone and mobile ticketing provides just that. To do so, different technologies can be used, such as Near Field Communication, Quick Response Codes and Bluetooth Low Energy. This paper explores the possibility of implementing a mobile ticketing solution, with focus on the ticket validation process, using these technologies. They are analyzed and compared at different levels and two possible approaches proposed. Both solutions are presented in terms of infrastructure and maintenance cost, as well as passenger interaction and benefit. The feasibility and performance of the technologies is analyzed and presented in the context of the proposed approaches. As a result, a mobile ticketing solution can be implemented using different technologies, and their choice depends on factors such as the available funds, the intended interaction level, performance and the size of the target audience.
2015
Autores
Silva, SM; Jesus, V; Marques, PH;
Publicação
Occupational Safety and Hygiene III
Abstract
This study contributes to identification of psychosocial risk factors in non-teaching staff. The study is exploratory and descriptive. It consists in descriptive statistics of responses to a questionnaire for identification of psychosocial risk factors (translated and adapted from F-PSICO), as well as in content analysis of responses to semi-structured interviews. The results show that the non-teaching staff needs to hide emotions and feelings and also that some of the situations that affect psychologically relate to relationships with co-workers. It is stated that «there is no team spirit» and that these relations are not satisfactory. With the day-to-day workload, these workers are forced to interrupt work and perform various tasks at the same time, dealing with a day-by-day of «breakneck pace», «intense» and «very full» journey. Psychological demands, time autonomy, workload, relationships and social support are psychosocial risk factors that play an important role in the performance of these workers. Finally, some measures to control these risks were recommended. © 2015 Taylor & Francis Group, London.
2015
Autores
Leitao, P; Rodrigues, N; Barbosa, J;
Publicação
PROCEEDINGS OF 2015 IEEE 20TH CONFERENCE ON EMERGING TECHNOLOGIES & FACTORY AUTOMATION (ETFA)
Abstract
In the nowadays highly unstable manufacturing market, companies are faced, on a daily basis, with important strategic decisions, such as "does the company has the necessary capacity to accept a high volume order?" or "what measures need to be implemented if the product demand increases x% a year?". Decision-makers, i.e. company's managers, rely on their experience and insights supported by classical tools to take such decisions. Classical mathematical solvers or agent-based systems are typical architectural solutions to implement strategic planning tools to support decision-makers on this important task Within the ARUM (Adaptive Production Management) project, a hybrid strategic planning tool was specified and developed, combining the optimization features of classical solvers with the flexibility and agility of agent systems. This paper briefly presents such architecture and focuses on the generation of the "what-if game" mechanism to support the generation of more intelligent and dynamic planning solutions.
2015
Autores
Ribeiro, C; da Silva, JR; Castro, JA; Amorim, RC; Fortuna, P;
Publicação
ON THE MOVE TO MEANINGFUL INTERNET SYSTEMS: OTM 2015 WORKSHOPS
Abstract
In the recent trend of data-intensive science, data publication is essential and institutions have to promote it with the researchers. For the past decade, institutional repositories have been widely established for publications, and the motivations for deposit are well established. The situation is quite different for data, as we argue on the basis of a 5-year experience with research data management at the University of Porto. We address research data management from a disciplined yet flexible point of view, focusing on domain-specific metadata models embedded in intuitive tools, to make it easier for researchers to publish their datasets. We use preliminary data from a recent experiment in data publishing to identify motivators and deterrents for data publishing.
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