Abstract: Modular multilevel converters (MMCs) are widely used in high-capacity pumped-storage variable-speed units and DC transmission systems owing to their low switching frequency and low losses.

Mammoth Cave in Kentucky stretches for more than 420 miles (675 kilometers) below the surface of the ground and is often described as the world’s largest cave system. Recent explorations there ...

Evolution Mining has delivered record cash flow and earnings in its 2026 financial (FY26) half-year results, supported by strong gold and copper production and growing contributions from key assets, ...

Most shark fossils are just teeth—their cartilage skeletons usually decay long before they can fossilize. But in northwestern Arkansas, a series of geological sites known as the Fayetteville Shale has ...