Single-phase generator The early generators for those single-phase traction networks are single-phase generators. Even with newer three-phase motors which were introduced to some modern trains, the single-phases transmission for traction networks survive their time and are still in use in many railways today. However, many traction power stations have replaced their generators over time to use three-phase generators and convert into single-phase for transmission. In the early development of hydroelectricity, single-phase generators played an important role in demonstrating the benefits of alternating current. In 1891, a 3,000 volts and 133 Hz single-phase generator of 100 horsepower was installed at Ames Hydroelectric Generating
Single-sex education Single-sex education Single-sex education, also known as single-gender education and gender-isolated education, is the practice of conducting education with male and female students attending separate classes, perhaps in separate buildings or schools. The practice was common before the 20th century, particularly in secondary and higher education. Single-sex education in many cultures is advocated on the basis of tradition as well as religion, and is practiced in many parts of the world. Recently, there has been a surge of interest and establishment of single-sex schools due to educational research. Single-sex education is practiced in many Muslim majority countries; while in the