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Laser Cladding:

Laser Cladding involves bonding of an overlay material to the surface to be hardened. The overlay material may be pre-positioned o it can be continously fed. The laser beam melts a thin sirface layer, similarly to the case of laser glazing. The overlay material is then metallurgically bonded to the surface. In contrast to glazing, the overlay material does not intermix with the surface. Only enough of the surface melts to form the bond with the overlay material. The process is also called hardfacing. Again, the laser would probably be a multikilowatt CO₂ laser.

(Industrial applications of lasers, John F. Ready, p. 381)

Solid-State Welding:

In solid state welding, coalescence of the part surfaces is achieved by pressure alone, heat and pressure. For some solid state processes, time is also a factor. If both heat and pressure are used, the amount of heat by itself is not sufficent to cause melting of the work surfaces. In other words, fusion of the parts would not occur using only the heat that is externally applied in the processes. In some cases, the combination of heat and pressure, or the particular manner in which pressure alone is applied, generates sufficient energy to cause localized melting of the faying surfaces. Filler metal is not added in solid state welding.

(Fundamentals of Modern Manufacturing: Materials, Processes, and Systems, Mikell P. Groover, p.732)

Attenuator:

Attenuators are either fixed or variable circuits to reduce signal amplitudes and/or improve return loss, while maintaining proper input and output impedance, of stages they are attached to. Attenuators are used extensively in wireless design.

Attenuation can be varied in discrete steps by a manually turned knob, or by electronic control. Other variable attenuators are actualy inserted between stages on a PCB, and can be either analog voltage or current controlled, with infinite attenuation resolution, while a digital step attenuator will have a limited number of discrete steps. All attenuators are rated for the maximum amount of attenuation they are capable of, along with their maximum frequency and input signal strength levels.

(Complete wireless design, Cotter W. Sayre, p.357)

Direct Numerical Control:

A Direct Numerical Control system operates with a remote central processor controlling several CNC machines via communication lines. The host computer dynamically downloads numerical data '' on the fly'' as CNC machines execute operations. When the system is equipped with adaptive control, feedback from the CNC machine tool allows for the evaluation of and possible intervention to the manufacturing process.

(Encyclopedia of production and manufacturing management, Paul M. Swamidass, p.160)