The inverted pendulum is a classic problem in dynamics and control theory and is widely used as a benchmark for testing control algorithms. It is also an area of active study, with many new innovations and applications - for example the problem is solved in the technology of the Segway, a self-balancing transportation device.

Stepping motor technology is well established and used for motion control, most notably for computer peripherals but also wherever digital control is employed. This book provides an introductory text which will enable the reader to both appreciate the essential characteristics of stepping motor systems and understand how these characteristics are being exploited in the continuing development of new motors, drives and controllers. A basic theoretical approach relating to the more significant aspects of performance is presented, although it is assumed throughout that the reader has no previous experience of electrical machines and is primarily interested in the applications of stepping motors. Paul Acarnley's outstanding reference book is widely known and used, and this, the 4th edition, has been significantly updated to include many new applications that have emerged since the previous edition was published. Coverage includes: drive circuits, accurate load positioning, static torque characteristics, multi-step operation, torque/ speed characteristics, high-speed operation, open-loop control, closed-loop control and microprocessor-based stepping motor systems.

Terahertz dielectric resonator antennas (DRAs) provide ultrafast data transfer rates using large bandwidth and multimode operations, which make them ideal for high speed communication due to their low loss and high efficiency. They can work at microwave, terahertz or optical frequencies, and are compact in size, which makes them well suited for advanced applications in sensing, scanning and imaging. New geometries are being developed for conical optical DRAs, cylindrical optical DRAs and spherical optical DRAs. Spherical optical DRAs have features of super directivity which can be used in quantum radars. Cylindrical optical DRAs with photo diodes can be used for wireless energy harvesting.