Effects of fertiliser practices on the growth and quality of two table grape cultivars: 'Cardinal' and 'D. Maria'.

In this study, the different fertilliser practices of four commercial vineyards (Vitis vinifera L. cv. 'Cardinal' and cv. 'D. Maria') in southern Portugal were assessed and compared in 2002. The vineyards were established in similar soils under the same climatic conditions and additional water was supplied by drip irrigation. At harvest, the mineral composition of petioles (P, K, Mg, Ca, Fe, Cu, Zn and Mn) and quality parameters of the grapes (total soluble solids expressed as degree Brix, cluster length and weight, number of grapes, grapes weight and rachis weight) were recorded. For the 'Cardinal' cultivar, the nutritional status of the plant was correlated with growth and yield, and the greatest values for most of the parameters studied were measured at Alvisquer farm. For the 'D. Maria' cultivar, a single correlation was found between nutrient levels and growth. Shoot and cluster lengths, and grape weight were similar at all farms, though cluster weight, number of grapes and total soluble solids were smaller at Pedras than at Alvisquer or Gomeira

Five really easy steps to build a homemade low-cost simulator

AIM: The aim of this study was to evaluate how simple it is to build a homemade low-cost simulator using a simple 5-step scheme. METHODS: A scheme explaining how to build an endoscopic surgery simulator in 5 easy steps was presented to 26 surgeons. The simulator required a pair of scissors and easy-to-find materials. Its total cost was less than €35. The participants assessed the simulator using common endoscopic training toys or ex vivo tissue and completed an anonymous query comparing it with other commercial simulators that they had experienced before. RESULTS: In all, 84.6% found the simulator really easy to build. Every participant felt that he or she could do the same simulator themselves. Comparing with other commercial available box simulators, the majority of participants found the homemade simulator easier to (a) mount and dismount, (b) transport, (c) clean, and (d) use when practicing alone. CONCLUSIONS: Anyone can build its own simulator for a small amount of money

On the Estimation of the Short-Circuit Impedance of Power Transformers Using Fractional Order Calculus

This paper reports investigation on the estimation of the short circuit impedance of power transformers, using fractional order calculus to analytically study the influence of the diffusion phenomena in the windings. The aim is to better characterize the medium frequency range behavior of leakage inductances of power transformer models, which include terms to represent the magnetic field diffusion process in the windings. Comparisons between calculated and measured values are shown and discussed

Research on the Portuguese building stock and its impacts on energy consumption – an average u-value approach

The article aims to evaluate the Portuguese building stock energy policies and strategy for energy saving in buildings among the EU members. It was found out the average heat transfer coefficients of the main structural elements of Portuguese Buildings and analyzed the U-values of this elements considering different time periods. The fundamentals of this study were funded by the Agency for Development and Innovation (ADI) and co-financed by the European Regional Development Fund (FEDER) through the Operational Program for Competitiveness Factors (POFC) assigned to the Building Physics and Construction Technology Laboratory with the reference SB Tool SPT_2011_4

Short-Circuit Impedance of Power Transformers: the Fractional Order Calculus Approach

First IFAC Workshop on Fractional Differentiation and Its Application - 19-21 July 2004, Enseirb, Bordeaux, France - FDA'04This paper reports investigation on the modeling of the short circuit impedance of power transformers, using fractional order calculus, analyzing the influence of the diffusion phenomena in the windings. This aims to better characterize the medium frequency range behavior of leakage inductances of power transformer models, which include terms to represent the magnetic field diffusion in the windings. Calculated and measured values are shown and compared

Evapotranspiração de referência para dimensionamento de sistemas de irrigação em Petrolina, PE.

A evapotranspiração é uma variável fundamental para estimar a exigência hídrica das culturas, e também fornece subsídio para o dimensionamento de sistemas de bombeamento, adução e distribuição de água na irrigação. A caracterização da distribuição de frequência da evapotranspiração de referência (ETo), estimada pelo método do tanque classe ?A? em Petrolina - PE, foi realizada com base em série histórica de dados de 1963 a 2010, os quais foram agrupados em períodos de 5, 10, 15 e 30 dias. As distribuições gama e normal foram aplicadas aos dados de ETo com probabilidade de 95, 90, 75, 50, 25, 10 e 5%, e foram aptas para representar os dados de evapotranspiração de referência para os períodos acumulados de 10, 15 e 30 dias. Os valores de ETo (11,06 e 11,07 mm dia-1, distribuição gama e normal, respectivamente) para o mês de outubro no período acumulado de 15 dias com probabilidade de 75%, foram os mais indicados para o dimensionamento da lâmina diária máxima de projetos de sistemas de irrigação

MAC protocol for low-power real-time wireless sensing and actuation

This paper presents LPRT, a new medium access control (MAC) protocol for wireless sensing and actuation systems. Some of the characteristics of the proposed protocol are low power consumption, support for real-time and loss intolerant traffic through contention-free operation and a retransmission scheme, flexibility, and high throughput efficiency. The LPRT protocol was implemented it in the MICAz motes, a platform for the development of wireless sensor networks. We also briefly describe a wireless hydrotherapy application that benefits from the use of the proposed protocol. This paper also provides experimental results and comparison of the proposed protocol with the CSMA/CA protocol of IEEE 802.15.4.Agência de Inovação (ADI)Fundação para a Ciência e a Tecnologia (FCT