Çeng

The çeng is a Turkish harp. It was a popular Ottoman instrument until the last quarter of the 17th century. The word comes from the Persian word "chang," which means "harp" (and also "five fingers").

The ancestor of the Ottoman harp is thought to be an instrument seen in ancient Assyrian tablets. While a similar instrument also appears in Egyptian drawings.

In the late 20th century, instrument makers and performers began to revive the çeng, with newer designs incorporating advanced tuning mechanisms such as those found on the kanun. Tone bending is also possible, by pressing on the string behind the bridge. Whereas the soundbox on the old çeng was on the upper part of the instrument, modern instruments have the soundbox on the lower part.

In 1995, Fikret Karakaya, a kemençe player from Turkey, made a çeng using the descriptions in the masnavi "Çengname" by the Turkish poet Ahmed-i Dai, and from Iranian and Ottoman miniatures from the 15th and 16th centuries. He presently plays and records with the instrument.

Regulation and licensure in engineering

Regulation and licensure in engineering is established by various jurisdictions of the world to encourage public welfare, safety, well-being and other interests of the general public, and to define the licensure process through which an engineer becomes authorized to practice engineering and/or provide engineering professional services to the public.

As with many other professions, the professional status and the actual practice of professional engineering is legally defined and protected by law. In some jurisdictions, only licensed engineers (sometimes called registered engineers) are permitted to "practice engineering," which requires careful definition in order to resolve potential overlap or ambiguity with respect to certain other professions which may or may not be themselves regulated (e.g. "scientists," or "architects"). Relatedly, jurisdictions that license according to particular engineering discipline need to define those boundaries carefully as well so that practitioners understand what they are permitted to do.