In the first part of this paper we show that the Shortest Common Superstring problem is NP-complete even if all strings are of the simple form 10plOq, p,q E N. This result closes the gap left between the polynomial cases where all strings are of the form Op104 or all strings are of the form lop1 and NP-complete cases when strings have a more complicated structure. In the second part of the pape...

We present in this paper a new evolutionary procedure for solving general optimization problems that combines eeciently the mechanisms of genetic algorithms and tabu search. In order to explore the solution space properly interaction phases are interspersed with periods of optimization in the algorithm. An adaptation of this search principle to the National Hockey League (NHL) problem is discus...

scheduling for job shop is very important in both fields of production management and combinatorial op-timization. however, it is quite difficult to achieve an optimal solution to this problem with traditional opti-mization approaches owing to the high computational complexity. the combination of several optimization criteria induces additional complexity and new problems. in this paper, we pro...

We study minimizing the sum of weighted completion times in a concurrent open shop. We give a primal–dual 2-approximation algorithm for this problem. We also show that several natural linear programming relaxations for this problem have an integrality gap of 2. Finally, we show that this problem is inapproximable within a factor strictly less than 6/5 if P 6= NP, or strictly less than 4/3 if th...

1. What is Memetics? 2. The State and Status of Memetics 3. Memetic Engineering in Human Societies 4. Memetic Engineering and Artificial Societies 5. What are Artificial Societies? 6. Memes in Artificial Societies 7. Evolutionary Game Theory Models 8. Memetic Models of Cultural Change 8.1. The Axelrod Cultural Model 8.2. The Swap Shop Model 8.3. The Open-Mind Model 8.4. The Stereotypes Model 9....

Flexible flow shop scheduling problem (also called blended flow shop scheduling problem) is a sort of complex Job Shop Scheduling problem. For the Flexible Flow Shop scheduling problem, only in very special cases, there are polynomial optimal algorithms. In most of the other cases, the problems are NP-Hard. It is a simplification of the original problem to solve Flexible flow shop scheduling wi...

Simulation technology holds tremendous promise for the manufacturing industry. A machine shop data model has been developed at the National Institute of Standards and Technology (NIST) to represent neutral machine shop data for supporting machine shop manufacturing simulation [1]. This paper discusses the data model and its application in manufacturing simulation. The paper also proposes an app...

In this paper, we analyze the characteristics of the dynamic job shop scheduling problem when machine breakdown and new job arrivals occur. A hybrid approach involving neural networks(NNs) and geneticalgorithm(GA) is presented to solve the dynamic job shop scheduling problem as a static scheduling problem. The objective of this kind of job shop scheduling problem is minimizing the completion ti...

We investigate cost-sharing mechanisms for scheduling cost-sharing games. We assume that the demand is general—that is, each player can be allocated one of several levels of service. We show how to design mechanisms for these games that are weakly group strategyproof, approximately budget-balanced, and approximately efficient, using approximation algorithms for the underlying scheduling problem...