Computer-aided process planning (CAPP) is an essential component of computer integrated manufacturing (CIM) system. A good process plan can be obtained by optimizing two elements, namely, operation sequence and th...Computer-aided process planning (CAPP) is an essential component of computer integrated manufacturing (CIM) system. A good process plan can be obtained by optimizing two elements, namely, operation sequence and the machining parameters of machine, tool and tool access direction (TAD) for each operation. This paper proposes a novel optimization strategy for process planning that considers different dimensions of the problem in parallel. A multi-dimensional tabu search (MDTS) algo-rithm based on this strategy is developed to optimize the four dimensions of a process plan, namely, operation sequence (OperSeq), machine sequence (MacSeq), tool sequence (TooISeq) and tool approach direction sequence (TADSeq), sequentially and iteratively. In order to improve its efficiency and stability, tabu search, which is incorporated into the proposed MDTS al- gorithm, is used to optimize each component of a process plan, and some neighbourhood strategies for different components are presented for this tabu search algorithm. The proposed MDTS algorithm is employed to test four parts with different numbers of operations taken from the literature and compared with the existing algorithms like genetic algorithm (GA), simulated annealing (SA), tabu search (TS) and particle swarm optimization (PSO). Experimental results show that the developed algo-rithm outperforms these algorithms in terms of solution quality and efficiency.展开更多
Three heuristic algorithms: simulated annealing, genetic algorithm, and Tabu search were compared to molecular docking procedure using 3 protein-ligand systems. Statistical analysis of the results indicated that the T...Three heuristic algorithms: simulated annealing, genetic algorithm, and Tabu search were compared to molecular docking procedure using 3 protein-ligand systems. Statistical analysis of the results indicated that the Tabu search showed the best performance in terms of locating solutions close to the crystallographic ligand conformation. From the comparisons, a hybrid search algorithm was proposed, which gave superior results compared with any one of the algorithms alone.展开更多
This paper describes a case study of 3D protein structure prediction of six sequences from protein data bank (PDB) by genetic algorithm and tabu search (GATS), where off-lattice AB model is considered as a simplif...This paper describes a case study of 3D protein structure prediction of six sequences from protein data bank (PDB) by genetic algorithm and tabu search (GATS), where off-lattice AB model is considered as a simplified model of protein structure. The lowest-energy values required for forming the native conformation of proteins are searched by GATS, and then the coarse structures (i.e., simplified structure) of the proteins are obtained according to the multiple angle parameters corresponding to the lowest energies. All the coarse structures form single hydrophobic cores surrounded by hydrophilic residues, which stay on the right side of the actual characteristic of protein structure. It demonstrates that this approach can predict the 3D protein structure effectively.展开更多
基金supported by the State Key Program of National Natural Science Foundation of China (Grant No. 51035001)National Natural Science Foundation of China (Grant Nos. 50825503, 50875101)
文摘Computer-aided process planning (CAPP) is an essential component of computer integrated manufacturing (CIM) system. A good process plan can be obtained by optimizing two elements, namely, operation sequence and the machining parameters of machine, tool and tool access direction (TAD) for each operation. This paper proposes a novel optimization strategy for process planning that considers different dimensions of the problem in parallel. A multi-dimensional tabu search (MDTS) algo-rithm based on this strategy is developed to optimize the four dimensions of a process plan, namely, operation sequence (OperSeq), machine sequence (MacSeq), tool sequence (TooISeq) and tool approach direction sequence (TADSeq), sequentially and iteratively. In order to improve its efficiency and stability, tabu search, which is incorporated into the proposed MDTS al- gorithm, is used to optimize each component of a process plan, and some neighbourhood strategies for different components are presented for this tabu search algorithm. The proposed MDTS algorithm is employed to test four parts with different numbers of operations taken from the literature and compared with the existing algorithms like genetic algorithm (GA), simulated annealing (SA), tabu search (TS) and particle swarm optimization (PSO). Experimental results show that the developed algo-rithm outperforms these algorithms in terms of solution quality and efficiency.
文摘Three heuristic algorithms: simulated annealing, genetic algorithm, and Tabu search were compared to molecular docking procedure using 3 protein-ligand systems. Statistical analysis of the results indicated that the Tabu search showed the best performance in terms of locating solutions close to the crystallographic ligand conformation. From the comparisons, a hybrid search algorithm was proposed, which gave superior results compared with any one of the algorithms alone.
基金Supported by the National Natural Science Foundation of China (60975031)the Scientific Research Foundation for the Returned Overseas Chinese Scholars of Ministry of Education of China, the Open Foundation of State Key Laboratory of Bioelectronics of Southeast University, China, and the Natural Science Foundation of Hubei Province, China (2008CDB344 and 2009CDA034)
文摘This paper describes a case study of 3D protein structure prediction of six sequences from protein data bank (PDB) by genetic algorithm and tabu search (GATS), where off-lattice AB model is considered as a simplified model of protein structure. The lowest-energy values required for forming the native conformation of proteins are searched by GATS, and then the coarse structures (i.e., simplified structure) of the proteins are obtained according to the multiple angle parameters corresponding to the lowest energies. All the coarse structures form single hydrophobic cores surrounded by hydrophilic residues, which stay on the right side of the actual characteristic of protein structure. It demonstrates that this approach can predict the 3D protein structure effectively.