Mechanical engineering including mechanical and chemical engineering. At its simplest, thermodynamics is the study of energy, its use and transformation through a system. Typically, engineering thermodynamics is concerned with changing energy from one form to another. As an example, automotive engines convert chemical energy (enthalpy) from the fuel into heat, and then into mechanical work that eventually turns the wheels. Thermodynamics principles are used by mechanical engineers in the fields of heat transfer, thermofluids, and energy conversion. Mechanical engineers use thermo-science to design engines and power plants, heating, ventilation, and air-conditioning (HVAC) systems, heat exchangers, heat sinks, radiators, refrigeration, insulation, and others.
Feathers: The Evolution of a Natural Miracle feathered flight has influenced human aviation. Hanson describes the behavior of birds-of-paradise and the role of their elaborate feathers in sexual selection. Hanson also visits the Las Vegas Strip and observes how feathers play a role in pageant shows like "Jubilee!". Hanson interviews Marios Ignadiou, the head of "Jubilee!"'s costume shop, as well as fashion designer Pete Menefree. Hanson then describes the history of the feather trade in fashion. In the period before World War I, feathers were highly valuable commodities. Wanting to capitalize on the economic strength of feathers, the government of South Africa sponsored the Trans-Saharan Ostrich Expedition,