We report on an ytterbium-free, erbium-doped single-mode all-fiber laser reaching a record output power of 107 W at 1598 nm, with slope efficiency 38.6% according to the absorbed pump 981 nm. The gain fiber, co-doped cerium, aluminum, and phosphorus, was fabricated in-house adjusted doping concentrations reduce erbium ions clustering, thereby increasing while keeping numerical aperture low ensu...

This study drew upon Kress and Van Leeuwen’s (2006, [1996]) visual grammar and Van Leeuwen’s (2008) social semiotic model to interrogate ways through which social actors of different races are visually and textually represented in four award-winning English-learning software packages.  The analysis was based on narrative actional/reactional processes at the ideational level; mood, perspective, ...

damping of a full-scale cable with a pair of passive–on magnetorheological (mr) dampers was tested. a cable of 215.58m long with the first mode frequency of 0.658hz was tensioned horizontally in cable prefabrication factory. two mr dampers were attached to the cable in an angle in the plane perpendicularly to the cable axis in 5m length from the cable anchorage. the applied voltage level was 0v...

in this study two modes ofreading (car and traditional print mode) were compared in regards to their effectiveness for l2 reading comprehension. a group of 120 english major students were divided into three classes: car, traditional, and control. based on the english proficiency scores each class was divided into two groups (high and low levels of proficiency). three classes were taught by the ...

This article presents a sliding mode control (SMC) with artificial neural network (ANN) regulator for the doubly fed induction generator (DFIG) using two-level neural pulse width modulation (NPWM) technique. The proposed control scheme of the DFIG-based wind turbine system (WTS) combines the advantages of SMC control and ANN regulator. The reaching conditions, robustness and stability of the sy...