Minimum-mean squared error (MMSE) receivers are designed and analyzed for multiple data rate direct-sequence code-division multiple-access (DS-CDMA) systems. The inherent cyclostationarity of the DS-CDMA signal is exploited to construct receivers for asynchronous multipath channels. Multipleand single-bandwidth access are treated for both single and multicarrier scenarios. In general, the optim...

If one of the surfaces which are in touch is rough and hard, it chips the other surface due to relative motion or touching forces. The wear is called two-body abrasive wear. If there are free abrasive particles between the two bodies, the wear is called three-body abrasive wear. The free abrasive particles may be external material dust or the remains of chipping. Usually, the wear starts as a t...

Cooperation and conflict are regarded as diametric extremes of animal social behaviour, yet the two may intersect under rare circumstances. We here report that territorial competitors in a common North American songbird species, the chipping sparrow (Spizella passerina), sometimes form temporary coalitions in the presence of simulated territorial intruders. Moreover, analysis of birds' vocal ma...

Nacrtak Conducted within the scope of a larger Italian project, the study analyzes three recovery alternatives for logging residue and identifies the conditions that make one preferable to the others. To the purpose, the authors used spreadsheet models based on experiments, which return the delivered cost of biomass as a function of working conditions and costing assumptions. Chipping, bundling...