Matriz Input-Output da região Alentejo: Acerca da Distribuição de Rendimento (3º quadrante)

No número 18 do “Boletim Trimestral” apresentámos os principais resultados do estudo que elaborou a Matriz Input-Output da Região Alentejo (MIO-Alentejo). Com este texto prosseguimos o propósito de divulgação dos resultados e conclusões do projeto, mas adotando agora uma perspectiva mais focalizada. Em particular, interessa-nos de momento olhar para o processo de formação do valor acrescentado, ou, de forma equivalente, para a distribuição do rendimento gerado na produção, sob a forma de remuneração dos diferentes fatores produtivos (3º quadrante). Nos pontos 2, 3, e 4 apresentamos os resultados e, em conclusão, deixamos algumas considerações finais no ponto 5. Anexamos um glossário com uma breve descrição metodológica.

Blade pitch control malfunction simulation in a wind energy conversion system with MPC five-level converter

This paper is on a wind energy conversion system simulation of a transient analysis due to a blade pitch control malfunction. The aim of the transient analysis is the study of the behavior of a back-to-back multiple point clamped five-level full-power converter implemented in a wind energy conversion system equipped with a permanent magnet synchronous generator. An alternate current link connects the system to the grid. The drive train is modeled by a three-mass model in order to simulate the dynamic effect of the wind on the tower. The control strategy is based on fractional-order control. Unbalance voltages in the DC-link capacitors are lessen due to the control strategy, balancing the capacitor banks voltages by a selection of the output voltage vectors. Simulation studies are carried out to evaluate not only the system behavior, but also the quality of the energy injected into the electric grid.

Improving Bangla ocr output through correction algorithms

Bangla OCR (Optical Character Recognition) is a long deserving software for Bengali community all over the world. Numerous e efforts suggest that due to the inherent complex nature of Bangla alphabet and its word formation process development of high fidelity OCR producing a reasonably acceptable output still remains a challenge. One possible way of improvement is by using post processing of OCR’s output; algorithms such as Edit Distance and the use of n-grams statistical information have been used to rectify misspelled words in language processing. This work presents the first known approach to use these algorithms to replace misrecognized words produced by Bangla OCR. The assessment is made on a set of fifty documents written in Bangla script and uses a dictionary of 541,167 words. The proposed correction model can correct several words lowering the recognition error rate by 2.87% and 3.18% for the character based n- gram and edit distance algorithms respectively. The developed system suggests a list of 5 (five) alternatives for a misspelled word. It is found that in 33.82% cases, the correct word is the topmost suggestion of 5 words list for n-gram algorithm while using Edit distance algorithm the first word in the suggestion properly matches 36.31% of the cases. This work will ignite rooms of thoughts for possible improvements in character recognition endeavour.