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This paper proposes an intelligent lighting system for bus interior environment using LEDs (light emitting diodes) controlled through an automotive communication network. The system consists on a master central control and slaves lighting modules, using a LIN (local interconnect network) network to perform communication. This network is a low cost alternative to the proposed system requirements, due to its low bit rate and physical needs. The slaves are independent lighting modules that supply a group of LEDs and measure the environment lighting level. The master sets LEDs module parameters (slaves), such as the state (on/off), and desired lighting level The master makes the user interface, sets the lighting parameters, as timer and lighting level and, more over, it establishes communication with other bus systems through a CAN (controller area network) gateway. This paper presents a complete logical description, including block and state diagrams, a physical description and some relevant experimental results.

This paper presents an electronic ballast to supply a 35 W high intensity discharge (HID) xenon lamp for automotive applications. The ballast consists on a bidirectional flyback operating in discontinuous conduction mode (DCM) and an igniter circuit. The converter supplies the lamp in a 400 Hz square waveform and the igniter is responsible for providing the necessary voltage for lamp start up. The purpose of this work is to supply the xenon lamp from a 12 V battery with a reduced number of components, decreasing the system final costs without penalty the reliability. Some experimental results are presented to validate the proposed ballast behavior.

This paper presents a high power factor electronic ballast for high pressure sodium lamps (HPS). The ballast consists of a single switch double-flyback and a half-bridge inverter. The double-flyback is responsible for PFC and lamp current limiting. The inverter stage supplies the lamp in a low frequency square waveform, avoiding lamp re-ignition and acoustic resonance phenomenon occurrence. Ballast project and experimental results are presented in order to verify the feasibility of the proposed topology

Artificial illumination control is one important topic to be addressed, considering that the energy expenses are substantial and solutions to optimize the use of energy are required. This work presents an integrated solution for electronic ballasts control of HPS lamps using the power lines as a transmission media. A message protocol will be implemented, with variables related to HPS lamps management. The protocol stack, including the physical layer, the media access control layer, the network layer and the application layer is designed focusing in the application purposed, i.e., energy management, light control and monitoring. A software application is designed so all units could be controlled and monitored remotely. Experimental results are presented in order to validate the integration between power lines and electronic ballasts to control HPS lamps.

This paper describes a self-oscillating electronic ballast, having fixed switching frequency, to supply four independent fluorescent lamps, with high power factor. To provide the power factor correction it was studied the modifications of the valley-fill filter, presented in the literature, choosing one that meets the IEC 61000-3-2 Class C requirements of the input current distortion. To drive the switches it was proposed a modification in the conventional self-oscillating driver, new in the literature, making it independent on the load of the ballast. So, it is built up the prototype and showed the experimental results.

One of the major challenges at the moment is the improvement of the present power system. The traditional power industry is outdated, but the responsibility is not just in the utility side. The consumer is being forced to perform a high quality load and ration the power consumption. A way to improve the power system is turn it intelligent, through a network. In this study, we analyze the features of a set of control fieldbuses and summarize the main features of a specific fieldbus for power management.

Submitted by Anabela Novais (anabelanovais@eseig.ipp.pt) on 2016-03-22T18:29:14Z No. of bitstreams: 1 DM_AureaMendes_2016.pdf: 1332334 bytes, checksum: 5da3ce320f973414ca82f6887a5bcd25 (MD5) Made available in DSpace on 2016-03-22T18:29:15Z (GMT). No. of bitstreams: 1 DM_AureaMendes_2016.pdf: 1332334 bytes, checksum: 5da3ce320f973414ca82f6887a5bcd25 (MD5) Previous issue date: 2016-02-01

Artificial illumination control is one important topic to be addressed, considering that the energy expenses are substantial and solutions to optimize the use of energy are required. This work presents an integrated solution for electronic ballasts control of HPS lamps using the power lines as a transmission media. A message protocol is implemented, with variables related to HPS lamps management. The protocol stack, including the physical layer, the media access control layer, the network layer and the application layer is designed focusing in the application purposed, i.e., energy management, light control and monitoring. A software application is designed so all units can be controlled and monitored remotely. Experimental results are presented in order to validate the integration between power lines and electronic ballasts to control HPS lamps.

Dissertação de Mestrado em Ciências da Comunicação O presente documento, resultante do estágio curricular no âmbito do 2º ciclo de estudos em Ciências da Comunicação, pretende analisar a “ A Eficácia da Comunicação Interna numa Organização Hospitalar ”, essencialmente estudar a este tipo de comunicação no Centro Hospitalar de Trás – os – Montes e Alto Douro, E.P.E, centrando-se sobretudo nos tipos de comunicação utilizados, ferramentas, barreiras existentes, entre outros pontos relevantes a este projeto, e tendo como principal objetivo analisar a Eficácia da Comunicação Interna numa Organização Hospitalar. Apresenta ainda todas as outras tarefas realizadas no departamento de Comunicação e Imagem do Centro Hospitalar de Trás – os – Montes e Alto Douro, E.P.E. This document is the result of a traineeship in the 2nd cycle of studies in Communication Sciences course. It aims to examine "The Effectiveness of Internal Communication in a Hospital Organization" essentially studying this type of communication in the Hospital Centre Trás - os - Montes e Alto Douro, EPE, mainly focusing on the types of communication used, tools, barriers, among other points relevant to this project, and having as main objective to analyze the Effectiveness of Internal Communication in a Hospital Organization. It also presents all the other tasks performed in the Department of Communication and Image of the Hospital Centre Trás - os - Montes and Alto Douro, EPE.

This paper presents a detailed analysis about valley fill filters applied to power factor (PF) correction of electronic ballasts. Comparative results about input current THD are done in this study, verifying if it meets the IEC 61000-3-2 standard requirements, that determines the maximum amplitude of each harmonic component from 2/sup nd/ up to 39/sup th/. Power factor (PF), total harmonic distortion (THD), crest factor (CF), auxiliary circuit losses, and operation principles are also presented.

This paper proposes a self-oscillating electronic ballast illumination system controlled by a low cost microcontroller. The microcontroller is used to detect presence and to measure the level of illumination in the environment. The dimming feature is achieved by displacing the operating frequency away from the system's resonant frequency, which is done by varying a resistance in the gate driver circuit. The paper includes an analysis of the proposed illumination system and its design. Experimental results are included to demonstrate its feasibility.