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Processing Additives: Processing Additives are materials used at relatively low dosage levels, which improve processsing characteristics without significantly affecting physical properties. In the early years, the classic additives such as mineral oil, bees wax, stearic acid, and palmitic acid, were used as a natural raw material, which did not have consistenet composition and quality. In recent years, they have increased in quality through appropriate processes. The growth rate of additives such as homogenizers, peptizers, and lubricants increased about four times between 1980 and 1995. The chemical structures of processing aids have been classified as hyrocarbons, fatty acid derivatives, synthetic resins, low molecular weight polymers, and organic thio compounds. Fatty acid esters act as both lubricants and dispersing agents. The advantages of using processing aids are improved product surface, improved production rate, reduction of die build-up, and reduction of gel formation. ( J. L. White,K. Kim, Thermoplastic and rubber compounds: technology and physical chemistry, p. 57) VFD: Vacuum florescent displays (VFD) invented in Japan in 1965 were originally used only in calculators. But now they are a practical display device consisting of flat multi-digit panels and is used in audio and video equipment, household electronics,, automobiles, office equipment and instrumentation. VFD tubes operate in the same way as CRTs. The filament (or filaments) is a very fine wire that is heated to a temperature just below incandescence. At that temperature it remains virtually invisible but it emits termo-electrons. Accelerated electrons emitted from cathode bombard anode coated with phosphor, the phosphor then emtis CL. But the kinetic energy of accelareted electrons in VFD is much small (10 to 100 V) compared to CRT (13-30 kV). In CRTs electron beam constructed into a fine beam is scanned over phosphor layer from top to bottom to produce image while in VFDs, electron beam is broadly diffused and irradiated layer segment gives the desired display. (A. Lakshmanan, Luminescence and Display Phosphors: Phenomena and Applications , p.67) DoE: Design of experiment is a statistical technique introduced by Sir R. A. Fisher in England in the early 1920s. His primary goal was to determine the optimum water, rain, sunshine fertilizer, and soil conditions needed to produce the best corp. Using the DOE technique, Fisher was able to lay out all combinations (also called treatments or trial conditions) of the factors included in the experimental study. The conditions were created using a matrix, which allowed each factor an equal number of test conditions. Methods for analyzing the results of such experiments were also introduced. When the number of combinations possible became too large, schemes were devised to carry out a fraction of the total possibilities such that all factors would be evenly present. Fisher devised the first method that made it possible to analyze the effect of more than one factor at a time. After Fisher introduced the technique and demonstrated its use in agricultural experiments, mush more research and development followed. Unfortunately, most of the work remained in the academic environment. Although the need to study multivariable effects is widespread in the industrial environment, not many industries other than a few segments of the chemical and fertilizer industries have applied the DOE technique in their production process. In fact, as academic knowledge grew, the further it got from a method that industry could absorb and apply. The more sophisticated the theory supporting DOE became, the less appealing it looked to practicing engineers. (R.K. Roy, Design of Experiments Using the Taguchi Approach:16 Steps to Product and Process Improvement, p.9) Pendant: A pendant is a relatively small hand-held device that the user plugs into either a USB or serial connection, allowing remote control of the machine (obviously within the limits of the length of the cord). Keys on the pendant are able to programmed or assigned various functions that are normally executed via the keyboard. Customary remote functions typically are; move, rapid, z touch off routine, pause, stop, file start, etc. There are several makes and modes of pendants available on the market and most require the use of plug in software to enable their use with controller software. An example of one these devices is the Shuttle Pro form http://contourdesign.com ; it is even possible to use your Xbox 360 controller (with Mach3). Here again, the user is responsible for determining which botton on the controller gets assigned a specific function. The pendant the author prefers does not require a plug-in as it is a keyboard emulator and works with any controller software. In addition you can build your own remote pendant. There are numerous free plans and examples avaliable on the Internet you can use. Building your own enables you to custom design one for your specific needs. (A. Overby, CNC Machining Handbook: Building, Programming, and Implementation, p.80)