During EDM process, the discharged energy produces very high temperatures at the point of the spark, causing a minute part of the sample to melt and vaporizes. With each discharge, a crater was formed on the machined surface. It was observed from Figure 5.4 SEM micrographs that, EDM surface produces irregular topography and defects included globules of debris, spherical particle, varying size craters and micro-cracks [29]. The surface topography was altered owing to significant electrical parameters such as Pulse on Time, Pulse off Time and Peak Current. The Pulse on Time and Peak Current are the most significant parameters that lead to deterioration of the surface texture. When Pulse on Time was increased then surface texture of the machined surface is composed of varying sizes of deep craters. These deep and overlapping craters were formed owing to successive electrical discharge, intense heat and local melting or vaporization of work material. Some of the molten material produced by the discharge was carried away by the kerosene. The remaining melt re-solidifies to form lumps of debris. Under shorter pulse on-time, the electrical sparks generate smaller craters on the work surface. Whereas the high pulsed current caused frequent cracking of dielectric fluid, which cause more melt expulsions and larger tensile stresses. These effects resulted in poor surface finish. At higher Peak Current, the impact of discharge energy on the surface of workpiece becomes greater and thus resulting erosion leads to the increase in deterioration of surface roughness.
The recast layer is the outer region of the heat affected zone and consists of superimposed strata derived from melted and resolidified workpiece material as seen in Figure 5. This l...
... middle of paper ...
... if ŷ < Ai di = 0 if ŷ > Bi
If the importance is same for each response, the composite desirability (DG), the geometric mean of all desirability functions, is given by
DG = (d1 x d2 x … x dnwn)1/n = (∏di)1/n where n = number of responses = 3.
It can be extensive to reflect the possible difference in the importance of different responses by giving weights. Where the weight wi satisfies 0 < wi < 1 and w1 + w2 + … + wn = 1
DG = (d1w1 x d2w2 x … x dnwn)1/n
Table 5.6 shows the constraints of input parameters and that of responses and the goal and weights assigned to each parameter. Table 5.8 shows the values of 36 levels of combinations of process parameters that will give a high value of composite desirability (ranged from 0.79 to 0.94). Table 5.7 gives the optimal input process parametric setting for multi-response optimization.
In future research, the opinion should be provided in multiple aspects and by more powerful evidences.
Riley, C.M. "Lahars." Geological and Mining Engineering Sciences. Michigan Tech. Web. 6 Feb. 2010. .
Discuss this view with detailed reference to your prescribed text and ONE other related text of
One of several articles that shows tried to study the importance and the factors that
During this study some of these theories will be applied , like
...or if the tasks were slightly different. In an aggregate level, these different situations were likely to have influenced the results they concluded on.
First, all data have both an objective and a subjective component. Numbers can be easily assigned to all qualitative data (such as open-ended questions in surveys), and any number obtained by a quantitative study is interpreted using a subjective or qualitative judgment. Second, using differen...
applies to human behavior, I believe human behavior is situation dependent and all three theoretical
In this case, the answer is to consider the importance of person-situation interactions. Traits and situations are both important factors, particularly how they interact; different situations affect different people
Remix Culture One of the biggest issues that arises with remix art is the issue of ‘Remix vs. Plagiarism.” When does a remixed work become an original work of art? Is the work considered original as soon as it is tweaked or when it is unrecognizable? Neither, a work is unique when its purpose and meaning transcends that of the original. Works like Montgomery Lee’s “Copyright Symphony” take a variety of images and use them to create music out of the embedded data in the photographs.
analysis in this essay I will be able to come to a conclusion as to
Heavy Metal music is a genre that has always been seen as music of the devil. This is due to the violence of the instruments and the supposed vehemence behind the lyrics. Heavy Metal music is a branch of rock and roll that began in the mid 1970’s with bands such as Led Zeppelin, Deep Purple, and Black Sabbath. This style of music is known for an overpowering drumbeat, distorted electric guitar, and clean vocals, with some screaming on the side. Adults and parents have seen such sounds as loud, disruptive, and harmful. However, Jon Pareles wrote in an article for the New York Times that rock and “speed metal” tell teens the truth about the world they live in and shows them that they are not alone in it. “Speed-metal bands strike a chord with millions of teen-agers because they reflect what's on their minds - and the songs tell them they are not alone”. Despite its bad reputation, heavy metal does a world of good for teenagers: it speaks to the dark side of life that most media ignores, and really communicates to teens that they are not forsaken. Heavy metal has been seen as a poison that infiltrates the minds of the youth and cultivates their dark desires; however, the distorted beats and piercing vocals actually represent an asylum for these young adults.
However, the approach presented by Adler et al. is more general compared to other two approaches. Both approaches from Takahashi and Adler et al. clearly define the problem by asking what, how, where, who and when questions, but Takahashi adds steps of identifying target system and background information at the beginning of assessment process.
deeper into this assessment then I did the other one in order to find the explanation of the
4. Question d: Explain the variables you should take into account when assessing page 4