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The diet of the White-bellied Sea-Eagle (Haliaeetus leucogaster) in Australia is poorly known, especially inland. The diet of the Wedge-tailed Eagle (Aquila audax) is better known, but the overlap in prey used by the two eagles has not been studied. In four inland territories of White-bellied Sea-Eagles, and five territories of Wedge-tailed Eagles nesting close to them (range 1.6–5.1 km apart) between July 2002 and December 2004, we identified 116 and 118 prey items from nests of White-bellied Sea-Eagles and Wedge-tailed Eagles respectively. There was little overlap between the diets, and that of Wedge-tailed Eagles was similar to that reported elsewhere. In addition to fish, White-bellied Sea-Eagles specialised in aquatic birds, such as cormorants, grebes or ducks, and aquatic reptiles, such as turtles or water dragons, but tended to avoid terrestrial birds and reptiles, such as ravens and skinks, or mammals such as European Rabbits (Oryctolagus cuniculus) and macropods that were the main prey of nearby Wedge-tailed Eagles. Though food niche breadth was almost identical for the two eagles, Wedge-tailed Eagles captured significantly larger prey, as indicated by the geometric mean prey weight. Our results indicate that closely located breeding pairs of riparian Wedge-tailed Eagles and White-bellied Sea-Eagles were not competing for food, owing to the differences in foraging preferences, at least during the breeding season. We found no evidence to support the claim that the spread of rabbits assisted the increase of breeding numbers of White-bellied Sea-Eagles.

In this work a position controller for the permanent magnet synchronous motor is developed. The design is based on ideas of time-optimal control and predictive control and considers constraints for both torque and speed. The proposed controller takes the form of a state feedback. Its inputs are the position reference and the system state, and its output is the switching state to be applied by the power converter in the next sampling instant. The design procedure starts by solving a time-optimal control problem for a simple system: the triple integrator. The solution is then used to devise a state feedback rule for the motor. Although the control scheme does not have a completely cascaded structure, the approach taken establishes a hierarchy, with the error in the position having the highest priority. This separates the controller in two main building blocks, which work at different abstraction levels. The purpose of the first block is to generate references for the relevant states of the motor (speed and torque), based on long term predictions, which are realized using the triple integrator model. The second block is a receding horizon controller with a prediction horizon of one time step and a specially devised cost function, for the simultaneous control of speed, torque and stator currents. The performance of the controller is verified with experimental results.

This paper presents the design of a control scheme for the two-mass-system based on the Finite-Set Model Predictive Control method. The whole system state is controlled in a centralized way, so that the problem is solved more holistically, that is to say, using all degrees of freedom available. Constraints in the prediction horizon, given by the limited computation power and speed of the system dynamics, and the consequent myopic perspective of the controller, are solved by means of an ad-hoc cost function. The control is done using measurements of the stator currents and the speed of the driving machine. The rest of the system state is estimated using a Kalman Filter.

In this paper the use of a Reduced Order Extended Kalman Filter, to estimate the rotor position of a Permanent Magnet Synchronous Motor, in coordination with a Predictive Torque Controller is proposed. The observer integrates the information provided by the fundamental model and the anisotropies of the machine, allowing for a wide operation range. The scheme takes advantage of the nature of the predictive controller, which applies one switching state of the inverter at a time for a whole sampling period, eliminating problems associated with pulse width modulation at low modulation indexes.

Multilevel converters can reach medium-voltage operation, increasing the efficiency in high power applications. Among the existing multilevel converter topologies, modular multilevel converter provides the advantages of high modularity, availability and high power quality. Moreover, the main advantage compared to cascaded multilevel converters is the absence of input transformer; reducing the size, cost and cooling requirements. When used as AC-AC converter, it usually requires a sophisticated controller to decouple the input and output frequency components. In this paper a predictive control approach is proposed to control a single-phase AC-AC modular multilevel converter. The controller minimizes the currents error and keeps the DC voltage balancing featuring a simple implementation, high input power factor and precise control of the output current. Moreover, the DC voltages are kept at the reference value. Simulation results showing the performance of the predictive control scheme are presented.

This paper presents a predictive strategy for the control of a permanent magnet synchronous motor (PMSM). Our approach allows one to simultaneously manipulate speed and electrical variables, without using any auxiliary linear controller. The high sampling rate, characteristic of this technique, and the limited precision of the typical angle measurement devices, present serious difficulties for this technique to work in practice. These issues are dealt with in the paper and a solution based on an extended Kalman filter is proposed. The effectiveness of the proposed approach is evaluated through simulations.

El hueso hioides esta colocado transversalmente por encima de la laringe y a la altura de la cuarta vertebra cervical, a nivel del angulo formado por la cara anterior del cuello y el piso de la boca, en forma de herradura o de ipsilon griega, de donde viene su nombre. Este hueso esta aislado del esqueleto, al que solo esta unido por ligamentos y musculos, siendo la division entre musculos suprahioideos e infrahioideos. El cuerpo esta formado por tres partes y de el salen dos prolongaciones: el asta mayor y el asta menor1. Presentamos el caso de una mujer de 28 anos de edad que acude a urgencias de nuestro hospital tras sufrir una caida mientras esquiaba, golpeandose en la region anterior del cuello con uno de los bastones. En la exploracion presenta una erosion superficial en la zona con intenso dolor en region central del cuello. Se solicita una radiografia lateral de partes blandas del cuello (fig. 1) donde se observa fractura del hueso hioides en la zona de union del asta mayor derecha con el cuerpo del hueso. Se trato de forma conservadora con inmovilizacion de la zona con collarin blando, analgesicos y antiinflamatorios. Figura 1. Radiografia lateral de partes blandas del cuello donde se aprecia una fractura del hueso hioides en la zona de union del asta mayor derecha con el cuerpo. La fractura del hioides es un tipo de fractura muy rara, correspondiendo al 0,002% de las fracturas2. En la literatura...

This paper presents the use of a predictive technique to control the currents in a PMSM, driven by a voltage source inverter. This method allows for a high quality current control without using linear controllers and modulators, resulting in a conceptually simple solution. Simulation an experimental results confirm the good performance of the drive controlled by this method.