ELECT An active add-on option for 208 VLL/60 Hz passive three-phase rectifiers is presented. The active optional circuit is implemented as ‘centretapped’ full-bridge stage and guarantees low-harmonic input currents and unity power factor. The active unit is able to operate for a wide frequency range and therefore applicable for high(e.g. >100 kW) and low-power applications. Some basic considera...

A progressive addition lens (or “PAL”) is a type of multifocal lens that employs a surface with a continuously smooth increase in addition (Plus) power. The curvature of the surface increases from its minimum value in the distance zone to its maximum value in the near zone (Figure 1). The total increase in surface power between these two zones is equal to the specified Add power of the lens. Th...

In the early 1990s, the low-end customer premises equipment (CPE) such as telephone, analog modem were the major products of Taiwan communication industry, and the local small to medium size corporations had limited resources for R&D in comparison with those of foreign advanced manufacturers. As the strength of the communication industry signified the critical index of a country’s competitive e...

In wireless networks, interferences between transmissions are modelled either in time or frequency domain. In this article, we jointly analyze interferences in the timefrequency domain using a stochastic geometry model assuming the total time-frequency resources to be a two-dimensional plane and transmissions from Internet of Things (IoT) devices timefrequency patterns on this plane. To evaluat...

This paper presents the development of an in situ measurement system known as the Debris Resistive Acoustic Grid Orbital Navy/NASA Sensor (DRAGONS). The DRAGONS system is designed to detect impacts caused by particles ranging from 50 μm to 1 mm at both low-earth and geostationary orbits. DRAGONS utilizes a combination of low-cost sensor technologies to facilitate accurate measurements and appro...

Power enhancement technologies for gas turbines such as inlet fogging, interstage water injection, saturation cooling, inlet chillers, and combustor injection are being used by end users without evaluating the potentially negative effects these devices may have on the operational integrity of the gas turbine. Specifically, the effect of these add-on devices, off-design operating conditions, non...

We experimentally demonstrate a microelectromechanically (MEMS) tunable photonic ring resonator add-drop filter, fabricated in a simple silicon-on-insulator (SOI) based process. The device uses electrostatic parallel plate actuation to perturb the evanescent field of a silicon waveguide, and achieves a 530 pm resonance wavelength tuning, i.e., more than a fourfold improvement compared to previo...