The first attempts to use standard-frequency single-phase AC were made in Hungary as far back as 1923, by the Hungarian Kálmán Kandó on the line between Budapest-Nyugati and Alag, using 16 kV at 50 Hz. The locomotives carried a four-pole rotating phase converter feeding a single traction motor of the polyphase induction type at 600 to 1,100 V. The number of poles on the 2,500 hp motor could be changed using slip rings to run at one of four synchronous speeds. The tests were a success so, from 1932 until the 1960s, trains on the Budapest-Hegyeshalom line (towards Vienna) regularly used the same system. A few decades after the Second World War, the 16 kV was changed to the Russian and later French 25 kV system.
What type of the converter was used in hungarian locomotives of that time?
four-pole rotating phase converter

According to conservation of energy, energy can neither be created (produced) nor destroyed by itself. It can only be transformed. The total inflow of energy into a system must equal the total outflow of energy from the system, plus the change in the energy contained within the system. Energy is subject to a strict global conservation law; that is, whenever one measures (or calculates) the total energy of a system of particles whose interactions do not depend explicitly on time, it is found that the total energy of the system always remains constant.
What can neither be created nor destroyed by itself; it can only be transformed?
energy

People of all ages attend, and many often move on to becoming imams.[citation needed] The certificate of an ʻālim, for example, requires approximately twelve years of study.[citation needed] A good number of the ḥuffāẓ (plural of ḥāfiẓ) are the product of the madaris. The madaris also resemble colleges, where people take evening classes and reside in dormitories. An important function of the madaris is to admit orphans and poor children in order to provide them with education and training. Madaris may enroll female students; however, they study separately from the men.[citation needed]
In what ways are madaris similar to western colleges?
people take evening classes and reside in dormitories