@article{BhattaraiHorbachStaatetal.2022,
  author    = {Bhattarai, Aroj and Horbach, Andreas and Staat, Manfred and Kowalczyk, Wojciech and Tran, Thanh Ngoc},
  title     = {Virgin passive colon biomechanics and a literature review of active contraction constitutive models},
  series = {Biomechanics},
  volume    = {2},
  journal   = {Biomechanics},
  number    = {2},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2673-7078},
  doi       = {10.3390/biomechanics2020013},
  pages     = {138 -- 157},
  year      = {2022},
  abstract  = {The objective of this paper is to present our findings on the biomechanical aspects of the virgin passive anisotropic hyperelasticity of the porcine colon based on equibiaxial tensile experiments. Firstly, the characterization of the intestine tissues is discussed for a nearly incompressible hyperelastic fiber-reinforced Holzapfel-Gasser-Ogden constitutive model in virgin passive loading conditions. The stability of the evaluated material parameters is checked for the polyconvexity of the adopted strain energy function using positive eigenvalue constraints of the Hessian matrix with MATLAB. The constitutive material description of the intestine with two collagen fibers in the submucosal and muscular layer each has been implemented in the FORTRAN platform of the commercial finite element software LS-DYNA, and two equibiaxial tensile simulations are presented to validate the results with the optical strain images obtained from the experiments. Furthermore, this paper also reviews the existing models of the active smooth muscle cells, but these models have not been computationally studied here. The review part shows that the constitutive models originally developed for the active contraction of skeletal muscle based on Hill's three-element model, Murphy's four-state cross-bridge chemical kinetic model and Huxley's sliding-filament hypothesis, which are mainly used for arteries, are appropriate for numerical contraction numerical analysis of the large intestine.},
  language  = {en}
}
@misc{TopcuMadabhushiStaat2022,
  author    = {Topcu, Murat and Madabhushi, Gopal Santana Phani and Staat, Manfred},
  title     = {Datasets from FEM Simulations done with COMSOL Multiphysics and Code_Aster},
  doi       = {10.6084/m9.figshare.19333295.v2},
  year      = {2022},
  abstract  = {Datasets from FEM Simulations done with COMSOL Multiphysics and Code_Aster for an elastic stress transfer between matrix and fibres having a variable radius.},
  language  = {en}
}
@inproceedings{TranTrinhDaoetal.2022,
  author    = {Tran, Ngoc Trinh and Trinh, Tu Luc and Dao, Ngoc Tien and Giap, Van Tan and Truong, Manh Khuyen and Dinh, Thuy Ha and Staat, Manfred},
  title     = {Limit and shakedown analysis of structures under random strength},
  series = {Proceedings of (NACOME2022) The 11th National Conference on Mechanics, Vol. 1. Solid Mechanics, Rock Mechanics, Artificial Intelligence, Teaching and Training},
  booktitle = {Proceedings of (NACOME2022) The 11th National Conference on Mechanics, Vol. 1. Solid Mechanics, Rock Mechanics, Artificial Intelligence, Teaching and Training},
  publisher = {Nha xuat ban Khoa hoc tu nhien va Cong nghe (Verlag Naturwissenschaft und Technik)},
  address   = {Hanoi},
  isbn      = {978-604-357-084-7},
  pages     = {510 -- 518},
  year      = {2022},
  abstract  = {Direct methods comprising limit and shakedown analysis is a branch of computational mechanics. It plays a significant role in mechanical and civil engineering design. The concept of direct method aims to determinate the ultimate load bearing capacity of structures beyond the elastic range. For practical problems, the direct methods lead to nonlinear convex optimization problems with a large number of variables and onstraints. If strength and loading are random quantities, the problem of shakedown analysis is considered as stochastic programming. This paper presents a method so called chance constrained programming, an effective method of stochastic programming, to solve shakedown analysis problem under random condition of strength. In this our investigation, the loading is deterministic, the strength is distributed as normal or lognormal variables.},
  language  = {en}
}