The position of a vehicle is to be detected accurately while suppressing the consumption of a battery. Various systems, methods, and software are described. The opening in each of the shaped abrasive particles can improve grinding performance by reducing the size of a resulting wear flat, can provide a reservoir for grinding aid, and can improve adhesion to a backing in a coated abrasive article. The material is preferably a composite, and may comprise closed cell, open face foam, such as compression moulded EVA foam. The server accepts data from a PBX or similar equipment in a telephone switch environment, and can use both real-time CTI communications links and asynchronous information sources such as the Station Message Detail Recording interface.