@article{9817,
  abstract     = {Elastic bending of initially flat slender elements allows the realization and economic fabrication of intriguing curved shapes. In this work, we derive an intuitive but rigorous geometric characterization of the design space of plane elastic rods with variable stiffness. It enables designers to determine which shapes are physically viable with active bending by visual inspection alone. Building on these insights, we propose a method for efficiently designing the geometry of a flat elastic rod that realizes a target equilibrium curve, which only requires solving a linear program. We implement this method in an interactive computational design tool that gives feedback about the feasibility of a design, and computes the geometry of the structural elements necessary to realize it within an instant. The tool also offers an iterative optimization routine that improves the fabricability of a model while modifying it as little as possible. In addition, we use our geometric characterization to derive an algorithm for analyzing and recovering the stability of elastic curves that would otherwise snap out of their unstable equilibrium shapes by buckling. We show the efficacy of our approach by designing and manufacturing several physical models that are assembled from flat elements.},
  author       = {Hafner, Christian and Bickel, Bernd},
  issn         = {1557-7368},
  journal      = {ACM Transactions on Graphics},
  keywords     = {Computing methodologies, shape modeling, modeling and simulation, theory of computation, computational geometry, mathematics of computing, mathematical optimization},
  location     = {Virtual},
  number       = {4},
  publisher    = {Association for Computing Machinery},
  title        = {{The design space of plane elastic curves}},
  doi          = {10.1145/3450626.3459800},
  volume       = {40},
  year         = {2021},
}

@article{11667,
  abstract     = {The focus of classic mechanism design has been on truthful direct-revelation mechanisms. In the context of combinatorial auctions, the truthful direct-revelation mechanism that maximizes social welfare is the Vickrey-Clarke-Groves mechanism. For many valuation spaces, computing the allocation and payments of the VCG mechanism, however, is a computationally hard problem. We thus study the performance of the VCG mechanism when bidders are forced to choose bids from a subspace of the valuation space for which the VCG outcome can be computed efficiently. We prove improved upper bounds on the welfare loss for restrictions to additive bids and upper and lower bounds for restrictions to non-additive bids. These bounds show that increased expressiveness can give rise to additional equilibria of poorer efficiency.},
  author       = {Dütting, Paul and Henzinger, Monika H and Starnberger, Martin},
  issn         = {2167-8383},
  journal      = {ACM Transactions on Economics and Computation},
  keywords     = {Theory of computation, Algorithmic game theory and mechanism design, Applied computing, Economics, Simplified mechanisms, Combinatorial auctions with item bidding, Price of anarchy},
  number       = {2},
  publisher    = {Association for Computing Machinery},
  title        = {{Valuation compressions in VCG-based combinatorial auctions}},
  doi          = {10.1145/3232860},
  volume       = {6},
  year         = {2018},
}