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As a new display technology, electrowetting display (EWD) has many excellent display characteristics, such as paper-like, low power consumption, quick response and full color. These characteristics make EWD devices very suitable for portable devices. However, the gray-scale distortion caused by the contact angle hysteresis of EWDs seriously affects the accuracy of gray-scale display. To improve this phenomenon, the hysteresis curve of an EWD panel was studied according to the motion characteristics of advancing contact angle and receding contact angle of oil in a pixel. Then, a driving scheme for EWDs using alternating current (AC) voltage instead of direct current (DC) voltage was proposed in this paper. And the advantages and disadvantages of the driving scheme at different AC frequencies from 90 to 2,700 Hz were analyzed through experiments. According to the stability of aperture ratio in EWDs, a 470 Hz AC driving scheme was determined. Experimental results showed that the aperture ratio distortion of EWDs could be reduced from 35.82 to 5.97%, which significantly improved the display performance of pixel units.

In this study, determining the location of coating defects and severities is evaluated using measurements along the Jordanian buried gas pipeline. Induced alternating current (AC) voltages and current densities along the pipeline are investigated using analytical and practical data under normal operation of the overhead transmission line. Since the induced AC voltages depend on the load currents, it is worthy to determine the actual load current during the lifetime of the pipeline. Accordingly, the forecasting of pipeline‐induced AC voltages is investigated using the least square method. The investigation is carried out in order to expect the future effects on the gas pipeline. The mitigation of induced AC voltage based on inserting polarisation cells (PCs) along the pipeline is evaluated. The results show that an agreement between the measured and calculated induced AC voltages is achieved with and without PCs. Based on the forecasting of induced AC voltages and current density along the pipeline, determining the number of PCs and allocations is suggested for the future years. This study increases the lifetime of the pipeline as well as decreases the maintenance cost. [ABSTRACT FROM AUTHOR]