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Positive definite separable quadratic programs for non-convex problems

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Abstract

We propose to enforce positive definiteness of the Hessian matrix in a sequence of separable quadratic programs, without demanding that the individual contributions from the objective and the constraint functions are all positive definite. For problems characterized by non-convex objective or constraint functions, this may result in a notable computational advantage. Even though separable quadratic programs are of interest in their own right, they are of particular interest in structural optimization, due to the so-called ‘approximated-approximations’ approach. This approach allows for the construction of quadratic approximations to the reciprocal-like approximations used, for example, in CONLIN and MMA. To demonstrate some of the ideas proposed, the optimal topology design of a structure subject to local stress constraints is studied as one of the examples.

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Notes

  1. Fleury (1979) and Wood and Groenwold (2009, 2010) have discussed nonconvex SAO algorithms, but these algorithms are all problem specific and they can hardly be considered ‘general’.

  2. It is in fact in general not possible to develop analytical relationships between the primal and the dual variables for weight minimization problems subject to multiple constraints, should a dual method be opted for, e.g. see (Groenwold and Etman 2008).

  3. If anything, the use of a continuation strategy seems to emphasize the computational advantage of exploiting non-convexity.

References

  • Bendsøe MP (1989) Optimal shape design as a material distribution problem. Struct Optim 1:193–202

    Article  Google Scholar 

  • Cheng G, Jiang Z (1992) Study on topology optimization with stress constraints. Engng Optim 20:129–148

    Article  Google Scholar 

  • Duysinx P, Bendsøe MP (1998) Topology optimization of continuum structures with local stress constraints. Int J Numer Meth Eng 43:1453–1478

    Article  MATH  Google Scholar 

  • Duysinx P, Zhang WH, Fleury C, Nguyen VH, Haubruge S (1995) A new separable approximation scheme for topological problems and optimization problems characterized by a large number of design variables. In: Ollhoff N, Rozvany GIN (eds) Proc. first world congress on structural and multidisciplinary optimization. Goslar, Germany, pp 1–8

    Google Scholar 

  • Etman LFP, Groenwold AA, Rooda JE (2009) On diagonal QP subproblems for sequential approximate optimization. In: Proc. eighth world congress on structural and multidisciplinary optimization, paper 1065. Lisboa, Portugal, June

  • Etman LFP, Groenwold AA, Rooda JE (2012) First-order sequential convex programming using approximate diagonal QP subproblems. Struct Mult Optim 45:479–488

    Article  MathSciNet  Google Scholar 

  • Fadel GM, Riley MF, Barthelemy JM (1990) Two point exponential approximation method for structural optimization. Struct Optim 2:117–124

    Article  Google Scholar 

  • Falk JE (1967) Lagrange multipliers and nonlinear programming. J Math Anal Appls 19:141–159

    Article  MathSciNet  MATH  Google Scholar 

  • Fleury C (1979) Structural weight optimization by dual methods of convex programming. Int J Numer Meth Eng 14:1761–1783

    Article  MATH  Google Scholar 

  • Fleury C, Braibant V (1986) Structural optimization: a new dual method using mixed variables. Int J Numer Meth Eng 23:409–428

    Article  MathSciNet  MATH  Google Scholar 

  • Groenwold AA (2012) On the linearization of separable quadratic constraints in dual sequential convex programs. Comput Struct. Available from Online First doi:10.1016/j.compstruc.2012.03.014

    Google Scholar 

  • Groenwold AA, Etman LFP (2008) Sequential approximate optimization using dual subproblems based on incomplete series expansions. Struct Multidisc Optim 36:547–570

    Article  MathSciNet  Google Scholar 

  • Groenwold AA, Etman LFP (2009) On the supremacy of reciprocal-like approximations in SAO - a case for quadratic approximations. In: Proc. eighth world congress on structural and multidisciplinary optimization, paper 1062. Lisboa, Portugal, June

  • Groenwold AA, Etman LFP (2010) A quadratic approximation for structural topology optimization. Int J Numer Meth Eng 82:505–524

    MathSciNet  MATH  Google Scholar 

  • Groenwold AA, Etman LFP (2011) SAOi: an algorithm for very large scale optimal design. In: Proc. ninth world congress on structural and multidisciplinary optimization, paper 035. Shizuoka, Japan, June

  • Groenwold AA, Etman LFP, Wood DW (2010) Approximated approximations for SAO. Struct Multidisc Optim 41:39–56

    Article  MathSciNet  Google Scholar 

  • Groenwold AA, Wood DW, Etman LFP, Tosserams S (2009) Globally convergent optimization algorithm using conservative convex separable diagonal quadratic approximations. AIAA J 47:2649–2657

    Article  Google Scholar 

  • Groenwold AA, Etman LFP, Kok S, Wood DW, Tosserams S (2009) An augmented Lagrangian approach to non-convex SAO using diagonal quadratic approximations. Struct Multidisc Optim 38:415–421

    Article  Google Scholar 

  • Kirsch U (1990) On singular topologies in optimum structural design. Struct Optim 2:133–142

    Article  Google Scholar 

  • Nocedal J, Wright SJ (2006) Numerical Optimization. Springer Series in Operations Research and Financial Engineering, 2nd edn. Springer

  • Rozvany GIN (2001) On design-dependent constraints and singular topologies. Struct Multidisc Optim 21:164–172

    Article  Google Scholar 

  • Rozvany GIN, Zhou M (1991) Applications of COC method in layout optimization. In: Eschenauer H, Mattheck C, Olhoff N (eds) Proc. engineering optimization in design processes. Berlin, Springer-Verlag, pp 59–70

    Chapter  Google Scholar 

  • Svanberg K (1987) The method of moving asymptotes - a new method for structural optimization. Int J Numer Meth Eng 24:359–373

    Article  MathSciNet  MATH  Google Scholar 

  • Svanberg K (2002) A class of globally convergent optimization methods based on conservative convex separable approximations. SIAM J Optim 12:555–573

    Article  MathSciNet  MATH  Google Scholar 

  • Vanderplaats GN (2004) Very large scale continuous and discrete variable optimization. In: Proc. 10th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, Albany, NY, U.S.A., August

  • Wood DW (2012) Dual sequential approximation methods in structural optimization. PhD dissertation, University of Stellenbosch, Stellenbosch, South Africa, Department of Mechanical and Mechatronic Engineering

  • Wood DW, Groenwold AA (2009) Non-convex dual forms based on exponential intervening variables, with application to weight minimization. Int J Numer Meth Eng 80:1544–1572

    Article  MathSciNet  MATH  Google Scholar 

  • Wood DW, Groenwold AA (2010) On concave constraint functions and duality in predominantly black-and-white topology optimization. Comp Meth Appl Mech Eng 199:2224–2234

    Article  MathSciNet  MATH  Google Scholar 

  • Zillober C (2002) SCPIP – an efficient software tool for the solution of structural optimization problems. Struct Multidisc Optim 24:362–371

    Article  Google Scholar 

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Acknowledgements

I am grateful indeed to my former student, Dr. Derren W. Wood, for enlightening discussions about some of the intricacies associated with the singularities that arise due to local stress constraints.

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Correspondence to Albert A. Groenwold.

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Groenwold, A.A. Positive definite separable quadratic programs for non-convex problems. Struct Multidisc Optim 46, 795–802 (2012). https://doi.org/10.1007/s00158-012-0810-8

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