In this paper, we derive, by presenting some suitable notations, three typical graph aLgorithms and corresponding programs using a unified approach, partition-and-recur. We putemphasis on the derivation rather than th...In this paper, we derive, by presenting some suitable notations, three typical graph aLgorithms and corresponding programs using a unified approach, partition-and-recur. We putemphasis on the derivation rather than the algorithms themselves. The main ideas and lugesnutty of these algorithms are revealed by formula deduction. Success in these examples givesus more evidence that partition-and-recur is a simple and practical approach and developingenough suitable notations is the key in designing and deriving efficient and correct algorithmicprograms.展开更多
This paper addresses linear time algorithms for parallel machine scheduling problems. We introduce a kind of threshold algorithms and discuss their main features. Three linear time threshold algorithm classes DT, PT a...This paper addresses linear time algorithms for parallel machine scheduling problems. We introduce a kind of threshold algorithms and discuss their main features. Three linear time threshold algorithm classes DT, PT and DTm are studied thoroughly. For all classes, we study their best possible algorithms among each class. We also present their application to several scheduling problems, The new algorithms are better than classical algorithms in time complexity and/or worst-case ratio. Computer-aided proof technique is used in the proof of main results, which greatly simplifies the proof and decreases case by case analysis.展开更多
Focusing on the ordinal scheduling problem on a parallel machine system, we discuss the background of ordinal scheduling and the motivation of ordinal algorithms. In addition, for the ordinal scheduling problem on ide...Focusing on the ordinal scheduling problem on a parallel machine system, we discuss the background of ordinal scheduling and the motivation of ordinal algorithms. In addition, for the ordinal scheduling problem on identical parallel machines with the objective to maximize the minimum machine load, we then give two asymptotically optimal algorithm classes which have worst-case ratios very close to the upper bound of the problem for any given m. These results greatly improve the results proposed by He Yong and Tan Zhiyi in 2002.展开更多
文摘In this paper, we derive, by presenting some suitable notations, three typical graph aLgorithms and corresponding programs using a unified approach, partition-and-recur. We putemphasis on the derivation rather than the algorithms themselves. The main ideas and lugesnutty of these algorithms are revealed by formula deduction. Success in these examples givesus more evidence that partition-and-recur is a simple and practical approach and developingenough suitable notations is the key in designing and deriving efficient and correct algorithmicprograms.
基金the National Natural Science Foundation of China(10301028,60021201)A preliminary version of this paper appeared in the proceedings of the 1st International Conference on Algorithmic Applications in Management,Lecture Notes in Computer Science 3521
文摘This paper addresses linear time algorithms for parallel machine scheduling problems. We introduce a kind of threshold algorithms and discuss their main features. Three linear time threshold algorithm classes DT, PT and DTm are studied thoroughly. For all classes, we study their best possible algorithms among each class. We also present their application to several scheduling problems, The new algorithms are better than classical algorithms in time complexity and/or worst-case ratio. Computer-aided proof technique is used in the proof of main results, which greatly simplifies the proof and decreases case by case analysis.
文摘Focusing on the ordinal scheduling problem on a parallel machine system, we discuss the background of ordinal scheduling and the motivation of ordinal algorithms. In addition, for the ordinal scheduling problem on identical parallel machines with the objective to maximize the minimum machine load, we then give two asymptotically optimal algorithm classes which have worst-case ratios very close to the upper bound of the problem for any given m. These results greatly improve the results proposed by He Yong and Tan Zhiyi in 2002.