The paper proposes a methodology for reliable design and maintenance of wind turbine rotor blades using a condition monitoring approach and a damage tolerance index coupling the material and structure. By improving the understanding of material properties that control damage propagation it will be possible to combine damage tolerant structural design, monitoring systems, inspection techniques a...

We describe a new fivefold symmetric approach to homonuclear recoupling in rotating solids that is based on rotor-synchronized, spin-lock rf irradiation of the type employed previously in MELODRAMA and C7 ~and their derivative sequences! for C– C recoupling. The fivefold sequence, like its sevenfold relatives, is g-encoded, and therefore exhibits a theoretical efficiency of ;73% for double quan...

The spinning limit for three different fibres (cotton, viscose rayon and polyester) on a Dref-3 friction spinning machine has been investigated. The change in yarn properties with progressive change in count has also been reported. The count range has been seen to be dependent on fibre type. As one progresses from very coarse to fine counts, the yarn tensile property remain fairly unaltered for...

The paper presents a general algorithm for the specification of a screw machine geometry. The conjugancy condition was solved numerically which thereby enables a variety of primary arc curves to be introduced. In addition, an optional numerical derivation of primary arcs enables any analytical function and even discrete point functions to be used for the primary arc. The approach also simplifie...

Although walking machines exhibit many advantages over wheeled or tracked vehicles, legged vehicles have yet to be introduced in real applications because of the primitive development of specific techniques such as gait generation. This article addresses the design, implementation and experimentation of gaits to negotiate uneven terrain with a real machine. The gaits presented are a mixture of ...

7 Acknowledgments We want to thank specially Stefan Mießbach for numerous contributions in proving the convergence properties of the net dynamic and for advice concerning the " cornered rat " example. We are very grateful to Ingrid Gabler for supplying the experimental data for this same example. 6.3 Convergence of the dynamic We show now the local convergence of the dynamic defined by the MF e...

The complex hydrogen-bonding arrangement in the biologically important molecule bilirubin IXalpha is probed by using 1H double-quantum (DQ) magic-angle spinning (MAS) NMR spectroscopy. Employing fast MAS (30 kHz) and a high magnetic field (16.4 T), three low-field resonances corresponding to the different hydrogen-bonding protons are resolved in a 1H MAS NMR spectrum of bilirubin. These resonan...

We are reporting four cases of serious washing machine related injury that presented within a period of 5 months. All patients were young children with the mean age of 9 year-old and three had their dominant hand injured. The washing machines involved were the automatic top loader type and all injuries occurred during the spinning phase. Serious automatic washing machine injury is not uncommon ...

This paper describes the dynamic behaviour of a doubly-fed induction machine, operating with wind turbine. The rotor circuit of the machine consists only of a generator-side converter working under abnormal condition at stator side (fault condition and voltage drop take place in transmission lines of the grid system). The induction machine model is based on the stationary reference frame and th...