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I have encountered this problem in a management paper...Here 'a' and 'p' are two group of jobs and b is a job in group 'a' and 'q' is job in group 'p'. They have defined the set "R' just to say that all the terms a,b,p,q are members of "R".. But what does the set physically mean?? pls help

is it related to arrival time of groups?? is it saying that group "a" arrived before "p" and if they both arrive together job "b" is processed before "q"?

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I'd have written $a,p,b,q$ as a tuple, thus: $\{(a,p,b,q) : \cdots\cdot\cdots\cdots \}$. ${}\qquad{}$ – Michael Hardy Jan 17 '14 at 17:59

It is saying the set of all jobs from $a, p, b$, and $q$ where $$ a < p\,\,\, \text{or}\,\,\, (a = p\,\,\, \text{and}\,\,\, b < q). $$ As for the physical interpretation, it seems like the paper was badly written if it left off what it means for one job to be equal or less than another.

Does that help at all?

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Thanks for the reply..i think i will have to mail to the author of the journal to get the best idea of it.. – Rajesh Jan 18 '14 at 15:09

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