Trim control mechanisms such as interceptors and trim flaps have been widely used in recent years in highspeed crafts for ride and trim control. In spite of their extensive application, a few studies investigating the impact of interceptors on planing craft performance, have been published. In the present study, the impact of interceptors on planing crafts hydrodynamic quality is investigated through application of an experimental method. Two scaled-down models of high-speed planing mono-hull and catamaran are tested with and without interceptors in calm water at different heights of the interceptors to investigate the effect of interceptors on drag reduction of the models. The first one is a scaled-down model of 11 m planing mono-hull boat and the test was conducted at the towing tank of Sharif

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An ethoxylated polyethylene wax (E-OPEW) was synthesized by PEGylation reaction between methoxy polyethylene glycol and oxidized PE wax. Clay nanoparticles were modified with different ratios of E-OPEW and then compounded with PP by the melt mixing process. E-OPEW and PP showed excellent compatibility, but at high percentages of wax (15%), incompatibility occurred between the two phases. In addition, the presence of modified clays in the PP matrix decreased the crystallinity percentage, though it did not change the melting temperature significantly. The results showed that functionalized wax is able to penetrate between clay platelets and increase the distance between them and improve their dispersion in the polymer matrix. Furthermore, it was observed that the distance between clay platelets increased by increasing E-OPEW content. In addition, this result led to a significant improvement in the barrier properties of clay platelets and the thermal stability of the modified nanocomposite compared to other cases. Despite the improved dispersion of nanoparticles, the mechanical strength of nanocomposites decreased at a high percentage of E-OPEW.

This paper discussed a transformer-less shunt static synchronous compensator (STATCOM) with consideration of the following aspects: fast compensation of the reactive power, harmonic cancelation and reducing the unbalancing of the 3-phase source side currents. The STATCOM control algorithm is based on the theory of instantaneous reactive power (P-Q theory). A self charging technique is proposed to regulate the dc capacitor voltage at a desired level with the use of a PI controller. In order to regulate the DC link voltage, an off-line Genetic Algorithm (GA) is used to tune the coefficients of the PI controller. This algorithm arranged these coefficients while considering the importance of three factors in the DC link voltage response: overshoot, settling time and rising time. For this investigation, the entire system including the STATCOM, network, harmonics and unbalancing load are simulated in MATLAB/SIMULINK. After that, a 35KVA STATCOM laboratory setup test including two parallel converter modules is designed and the control algorithm is executed on a TMS320F2812 controller platform.

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