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The simulations and experiments for two 400 W low‐speed direct‐drive permanent magnet synchronous generators (PMSGs) installed in a Floating Kuroshio Turbine (FKT) were implemented. The towing tank experiments were carried out at National Taiwan University. A generator can start to harvest current energy at the rotation speed of 30 rpm (corresponding to the current flow rate of 0.36 m/s), and produce the rated power of 400 W at 150 rpm. The speed is very low compared with the published reports. The energy conversion efficiency of the FKT is up to 0.85. The results show that the generated direct current (DC) power is more than 800 W at a flow rate of 1.5 m/s. The power coefficient for the FKT is about 0.4. The energy loss at each stage and the power difference between the testing platform and the towing tank experiment were also analyzed. Moreover, the shape of the FKT is a new design. Compared with other structures, the proposed FKT can easily follow the direction of the ocean current and the depth of the FKT can be adjustable; when it doesn't operate, it will float on the surface so that it is easy for maintenance. [ABSTRACT FROM AUTHOR]

Herein, solution‐processed indium gallium zinc oxide (IGZO) thin‐film transistor (TFT) is fabricated utilizing metal nitrates as precursors, and the impact of nitrate ions in different solvents on the performances of IGZO TFT is demonstrated. During IGZO film fabrication, the nitrogen in nitrate species actually dopes into the film in the fashion of different chemical states depending on different solvents. When IGZO precursors dissolve in deionized water (DIW), due to the high polarity of the solvent, metal nitrates are completely dissociated, leading to the conversion of nitrates to nitrides in IGZO film. This nitrogen decreases the density of the interface trap states, thus improving the characteristics of the IGZO TFT. In contrast, when using 2‐methoxyethanol (2‐ME) as the solvent, nitrogen mainly forms nitrogen oxide and acts as a trap density that leads to the degradation of the device performances. By increasing the annealing temperature of IGZO film, nitrogen oxide can convert to metal nitride, resulting in enhanced device performance. The IGZO TFT fabricated using DIW as a solvent with 300 °C annealing temperature exhibits the saturation mobility of 2.5 cm2 V−1 s−1 and Ion/off ratio of >106.5. Herein, a step is made toward the solvent effect on the performance of solution‐processed oxide TFT. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a balanced pulse-modulated polar transmitter that is capable of withstanding load mismatch and out-of-band reflection. The balanced architecture directs the reflected power to the isolated port of the 90°-hybrid coupler. Using a rectifier, the reflected power can be recycled and used for assisting the supply of the polar transmitter. A prototype system was implemented and measurement was performed for validation. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1452-1454, 2014 [ABSTRACT FROM AUTHOR]