The magic hat : a tool for intervention on language disorders

"As perturbações da linguagem apresentam um elevado risco para dificuldades de aprendizagem e podem comprometer a inserção escolar e social das crianças afetadas. Quando a fala não se constitui como um meio de linguagem expressiva, torna-se muito importante proporcionar à criança uma intervenção terapêutica precoce.Com este propósito foi criado um instrumento lúdico-pedagógico para a terapia de fala, capaz de dar suporte conjunto aos cinco domínios linguísticos e que é facilmente apreendido pela criança, favorecendo a sua aprendizagem. O instrumento de intervenção designado por “A Cartola Mágica” é personificado num gato com uma cartola anatomicamente compartimentada em forma de gavetas, simbolizando os cinco domínios da linguagem, destinado a crianças com idades compreendidas entre os 5 e os 8 anos. O instrumento pode ser utilizado em várias vertentes linguísticas, de acordo com os objetivos terapêuticos pretendidos. O instrumento apresenta como limite a portabilidade do modelo criado e, como alcance empírico, o fato de incluir todos os domínios da linguagem e ser de fácil aplicação em settings terapêuticos restritos.""Language disorders are connected with a high risk of learning difficulties and may compromise the school and social integration of the affected children. When speech is not constituted as a way of expressive language, it becomes very important to provide the child with an early therapeutic intervention. For this purpose was created a pedagogic and ludic instrument in the field of speech therapy conjointly, in the five branches of speech, easily comprehended by children, supporting their learning. The instrument of gradual intervention entitled “The Magic Hat” is personified as a cat with a hat anatomically compartmentalized in drawers, symbolizing the five branches of language, intended for children aged 5-8 years. The instrument maybe used in different ways, to archive the therapy goals that the therapist has with a particular child. The portability of the macromodel created is a limitation of this instrument and its empirical lead is the fact that it includes all language areas and it is very easy to be implemented in limited therapeutic settings.

Actuador linear de relutância variável comutado, modelização, dimensionamento, construção e ensaio.

Esta dissertação incide sobre a análise do actuador linear de relutância variável comutado, no que diz respeito à sua modelização, ao seu dimensionamento optimizado, à sua construção e ao seu ensaio. Estes actuadores, de fluxo longitudinal e de fluxo transversal, são raramente referidos na literatura científica, e a abordagem à sua análise é praticamente inexistente. A introdução a este tema é feita recorrendo aos motores de relutância variável comutados rotativos, sendo posteriormente apresentada uma breve referência aos actuadores lineares, como máquinas que resultam da manipulação geométrica das máquinas rotativas. Evoluindo no sentido dos actuadores objecto desta dissertação, propõe-se uma metodologia de dimensionamento, de carácter analítico, de actuadores lineares de topologia tubular e de topologia plana. Por aplicação da metodologia proposta, e com o objectivo de tornar automática a tarefa de dimensionamento destes actuadores, bem como facilitar a sua selecção, propõe-se um programa de computador. O actuador de relutância variável comutado apresenta uma geometria irregular, física e electromagneticamente não homogénea, exigindo que a análise do seu desempenho, para as diferentes posições relativas entre o primário e o secundário, e para diferentes parâmetros da máquina, seja conduzida mediante a aplicação de métodos numéricos, permitindo, assim, o seu dimensionamento optimizado. As características teóricas do actuador, magnéticas e funcionais, obtidas através do método de elementos finitos, são, por último, comparadas com os resultados obtidos nos ensaios laboratoriais de um protótipo optimizado, que foi construído

An Experimental Analysis of the Electrical Parameter Variation of a Photovoltaic Module

Photovoltaic (PV) energy has been asserting itself in recent years as a true alternative for the electricity production in the future. It is well known that the accuracy of PV parameters is crucial to achieving optimal control of PV systems under any operating conditions. Although many attempts have been made to study the operating ranges of PV parameters, this remains a  current research topic given the diversity of  PV technologies. In this paper, the PV parameters variation with irradiance and temperature levels is experimentally analysed for a polycrystalline (poly-Si) silicon PV module. The experiment considers experimental data from 130 I-V characteristic curves measured over a typical day, considering several irradiance and temperature levels in the range 29–1023 W/m2 and 19–68 °C, respectively. The results show that PV parameters vary considerably with irradiance and temperature levels for poly-Si technology. Keywords: Photovoltaic module, Photovoltaic parameters, Singe-diode model, Irradiance and temperature influenc

Current Control Optimization for Grid-tied Inverters Using Cuckoo Search Algorithm

One of the most decisive factors for a smooth and stable operation of an DC / AC converter connected to the power grid are the gains used in the current controllers. This paper proposes the use of the Cuckoo Search optimization algorithm via Lévy Flights to facilitate the determination of the optimal gains of the grid connected DC/ AC converters. With the proposed algorithm, it becomes possible to determine the optimal gains of the current controllers of the DC / AC converters connected with the grid thus improving their stability, accuracy and response time. Keywords: DC/AC converters, Cuckoo search, Optimization, Current controller

Numerical and Experimental Analysis of Vibrations in a Three-Phase Linear Switched Reluctance Actuator

This chapter focuses on the analysis and characterization of the vibrations produced by switched reluctance actuators. The emphasis stands on the linear configuration of this type of machine. The complexity of the mechanical system and the materials is used to define the modal frequencies. Moreover, the power controller topology, the excitation regimes, and the switching frequency used for the actuator operation can excite the natural modes and put restrictions on its usage. The analysis considers both numerical and experimental methodologies. The numerical technique relies on the finite element method (FEM) using the 3D model of the actuator to find its natural frequencies up to ∼1.3 kHz. The experimental characterization counts on the operational modal responses and the acoustic noise emitted. We identify the regions of interest to measure the local accelerations and collect data for post-processing and record the audible noise emitted for signal analysis. The popular discrete Fourier transform and the joint wavelet-Fourier analysis are used for signal analysis. The reliability and the suitability of this approach are verified comparing both the numerical and the experimental outcomes and support the identification of the switching frequencies with high potential to excite the natural modes under the regular operation of the machine and to choose the proper control strategy

Control and Dynamic Simulation of Linear Switched Reluctance Generators for Direct Drive Conversion Systems

This chapter addresses the dynamic simulation and control of linear switched reluctance generators for direct drive conversion systems. The electromechanical energy conversion principles of linear switched reluctance machines are briefly explained. A detailed mathematical model is developed for linear switched reluctance generators. The different types of control strategies adopted for switched reluctance generators are referred. The hysteresis controller is applied to control the conversion system with constant damping load. The proposed control strategy also includes a DC/DC isolated converter to control the system DC bus voltage by adjusting the energy flow between the conversion system and the resistive load. The mathematical model is applied to simulate the behavior of a tubular linear switched reluctance generator as power take-off system in an ocean wave point absorber device. To accomplish this task, the dynamic equations of the point absorber are presented and integrated with the linear switched reluctance generator dynamic model. In the simulation process, the system is driven by a regular ocean wave and operates with constant damping load. The system performance is evaluated for different load values, and the simulation results are presented for the optimal damping load case scenario

Controller Design and Experimental Validation of a Solar Powered E-bike Charging Station

Electric Vehicles (EV) have gained interest over the past decade. Because of this, to support EV technology installation of charging stations are required. Charging EVs from renewable energy provides a sustainable means of transport. E-bikes can help mitigate some mobility problems, particularly in large cities and metropolitan areas. This paper shows the development and implementation of a solar e-bike charging station with photovoltaic production, with energy storage system. The implemented system has a centralized control and allow an efficient management of the various resources and contemplates the possibility of four simultaneous e- bikes where user identification is performed by RFID. Finally, it is provided a user interface through an HMI panel and a web page where it will be possible to access the DataLog to consult the user activity and all charging parameters. Keywords: Renewable energy, Solar charging station, Programmable logic controller &nbsp

Maximum Power Point Tracking for a Point Absorber Device with a Tubular Linear Switched Reluctance Generator

This paper addresses the control of a Tubular Linear Switched Reluctance Generator (TLSRG) with application in a point absorber device. A maximum power point tracking (MPPT) strategy is proposed to maximize the power extraction from ocean waves. The generator is characterized by average maximum force of 120 kN and a maximum velocity of 1.3 m/s. The proposed MPPT is achieved by changing the generator damping load according to the excitation force induced by a regular wave. A hysteresis controller is applied to regulate the phase current intensity which allows the control of the linear force provided by the generator. The conversion system direct current (DC) bus voltage is adjusted by an isolated DC/DC converter with a proportional integral controller to define the appropriate duty-cycle