A piston pump & motor is a type of reciprocating pump that moves and pressurizes fluid by using one or more reciprocating pistons; it is typically driven by an electric motor through a crankshaft and connecting rod. Though there are many types, all piston pumps feature at least one piston moving in an enclosed cylinder.
http://www.phpfluid.com/piston-pump/

Oxygen concentrator is an electrically operated medical device which provides purified oxygen. This device works by pumping indoor air into a container that separates oxygen from room air and concentrates it to provide oxygen continuously to users.
http://www.nuzhuoasu.com/oxygen-concentrator/

Once the board has paste applied, the components are placed on top. This can be done by hand or by a machine. Using tweezers is a great way to place components. There is a common fallacy that you need large, expensive machines to make electronics.
http://www.etonautosmtmachine.....com/led-pick-and-pla

A pressure transmitter is a mechanical device that measures the expansive force of a liquid or gaseous sample.
Also known as a pressure transducer, this type of sensor is typically composed of a pressure sensitive surface area made of steel, silicon, or other materials depending upon the analyte’s composition.
http://www.enbbonsensor.com/pressure-transmitter/

If you have doubts on the differences between fiber pigtails and fiber patch cords this article will help you to know their main differences. The main difference between these two cables is that pigtails have one side terminated with a connector and other side ends with bare fibers, while patch cords have two connectors terminated on both ends. Let’s see in more detail how these assemblies are used and how are they distinguished.
http://www.cobtel.com/patch-cord-or-jumper/