M. Liang

University of Ottawa, Ottawa, Ontario, Canada

Are you M. Liang?

Claim your profile

Publications (5)8.37 Total impact

  • F. Kolahan, M. Liang
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper addresses a single machine sequencing problem with variable processing times and sequence-dependent setups. The objective is to find the best trade-off between the JIT goal and the processing time compression and extension costs by simultaneously determining the job sequence and processing times for concerned jobs. Due to the combinatorial nature of the problem, it cannot be optimally solved in polynomial time. A tabu search approach is used to provide good and quick solutions. To improve the computational efficiency, an adaptive neighbourhood generation method is proposed and used in the tabu search algorithm. A total of 100 problems of different sizes have been solved to test the proposed approach. Our computational experience shows that the adaptive approach outperforms several other neighbourhood generation methods in terms of both convergence rate and solution quality. The effects of the search parameters are also discussed.
    European Journal of Operational Research 02/1998; 109(1):142-159. DOI:10.1016/S0377-2217(97)00098-2 · 1.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In the metal cutting industry, a large amount of time is often spent on data exchange, NC tool path generation and NC program preparation. To reduce the production cycle, the CAD model should be represented in a neutral format so that it can be readily used in CAM and the tool path should be automatically generated from the neutrally documented CAD model. The emerging STEP data exchange standard provides such a neutral format which is independent of any software and hardware. This paper reports the development of a STEP based tool path generation system for rough machining of planar surfaces. The system includes four components: a data extraction module, a volume slicing module, a CL file generation module and an NC code generator. The proposed system has been implemented in a UNIGRAPHICS CAD/CAM environment. The application of the system is illustrated using an example part.
    Computers in Industry 12/1996; DOI:10.1016/S0166-3615(96)00060-7 · 1.46 Impact Factor
  • Source
    D. Manuel, M. Liang, F. Kolahan
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents a method to automatically generate NC toolpaths with dynamic elimination of machining errors in arbitrarily shaped convex pockets. The proposed method generates a spiral-like tool path by computing optimal offsets of the pocket boundary contour based on the size of the milling cutter and the pocket contour geometry. This dynamic tool path generating technique is demonstrated herein with an example.
    Computers & Industrial Engineering 10/1996; 31(1-2-31):135-138. DOI:10.1016/0360-8352(96)00096-4 · 1.69 Impact Factor
  • Source
    F. Kolahan, M. Liang
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper reports a tabu-search approach to minimize the cost in hole making processes. Four issues, namely, tool travel scheduling, tool switch scheduling, tool selection, and machining speed specification have been simultaneously addressed in this study. This problem has a structure similar to the Travelling Salesman Problem (TSP) and hence is NP-complete. To provide an efficient solution procedure, a tabu search approach has been proposed. The performance of the proposed approach is tested using an example problem.
    Computers & Industrial Engineering 10/1996; 31(1):371-374. DOI:10.1016/0360-8352(96)00154-4 · 1.69 Impact Factor
  • F. Kolahan, M. Liang, M. Zuo
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper addresses a joint part sequencing and tool replacement problem on an automated machining center. The objective is to minimize the expected production cost subject to available spare tools. In the literature, it has been shown that the sequencing problems with sequence-dependent setups are equivalent to the “travelling salesman problem” (TSP) and thus are NP-complete. The problem under consideration is further complicated by the position-dependent cost components associated with tool replacement decisions. To provide an efficient planning tool for shop floor decision making, a tabu search approach is proposed. The application of the proposed approach is demonstrated using an example problem. Our computational experience shows that good solutions can be found within a relatively short search time. The impact of tool spare level on the performance of the machining center is also examined. Finally, the effects of tabu-list size and path diversification are discussed.
    Computers & Industrial Engineering 10/1995; 28(4-28):731-743. DOI:10.1016/0360-8352(95)00018-V · 1.69 Impact Factor