Polynomial-time approximation schemes for scheduling problems with time lags
نویسندگان
چکیده
منابع مشابه
Polynomial-time approximation schemes for scheduling problems with time lags
We identify two classes of machine scheduling problems with time lags that possess Polynomial-Time Approximation Schemes (PTASs). These classes together, one for minimizing makespan and one for minimizing total completion time, include many well-studied time lag scheduling problems. The running times of these approximation schemes are polynomial in the number of jobs, but exponential in the num...
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Let Π be an NP-hard optimization problem, and let A be an approximation algorithm for Π. For an instance I of Π, let A(I) denote the objective value when running A on I, and let OPT (I) denote the optimal objective value. The approximation ratio of A for the instance I is RA(I) = A(I)/OPT (I), thus, when Π is minimization (maximization) problem RA(I) ≥ 1 (RA(I) ≤ 1). A polynomial time approxima...
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ژورنال
عنوان ژورنال: Journal of Scheduling
سال: 2009
ISSN: 1094-6136,1099-1425
DOI: 10.1007/s10951-009-0134-8