TY  - RPRT
A1  - Bhattarai, Aroj
A1  - Frotscher, Ralf
A1  - Durong, Minh Tuán
A1  - Staat, Manfred
T1  - Schlussbericht zu BINGO. Optimierung des Systems Netzimplantat-Beckenboden zur therapeutischen Gewebeverstärkung nach der Integraltheorie.
Y1  - 2016
N1  - Förderkennzeichen BMBF 03FH073PX2
CY  - Aachen
ER  - 
TY  - CHAP
A1  - Bhattarai, Aroj
A1  - Frotscher, Ralf
A1  - Staat, Manfred
T1  - Computational Analysis of Pelvic Floor Dysfunction
T2  - Women's Health and Biomechanics
N2  - Pelvic floor dysfunction (PFD) is characterized by the failure of the levator ani (LA) muscle to maintain the pelvic hiatus, resulting in the descent of the pelvic organs below the pubococcygeal line. This chapter adopts the modified Humphrey material model to consider the effect of the muscle fiber on passive stretching of the LA muscle. The deformation of the LA muscle subjected to intra-abdominal pressure during Valsalva maneuver is compared with the magnetic resonance imaging (MRI) examination of a nulliparous female. Numerical result shows that the fiber-based Humphrey model simulates the muscle behavior better than isotropic constitutive models. Greater posterior movement of the LA muscle widens the levator hiatus due to lack of support from the anococcygeal ligament and the perineal structure as a consequence of birth-related injury and aging. Old and multiparous females with uncontrolled urogenital and rectal hiatus tend to develop PFDs such as prolapse and incontinence.
KW  - Pelvic muscle
KW  - Muscle fibers
KW  - Passive stretching
KW  - Pelvic floor dysfunction
Y1  - 2018
SN  - 978-3-319-71574-2
U6  - https://doi.org/10.1007/978-3-319-71574-2_17
N1  - Lecture Notes in Computational Vision and Biomechanics, vol 29
SP  - 217
EP  - 230
PB  - Springer
CY  - Cham
ER  - 
TY  - THES
A1  - Frotscher, Ralf
T1  - Electromechanical modeling and simulation of thin cardiac tissue constructs - smoothed FEM applied to a biomechanical plate problem
Y1  - 2016
N1  - Duisburg, Essen, Universität Duisburg-Essen, Diss., 2016
ER  - 
TY  - JOUR
A1  - Colombo, Daniele
A1  - Drira, Slah
A1  - Frotscher, Ralf
A1  - Staat, Manfred
T1  - An element-based formulation for ES-FEM and FS-FEM models for implementation in standard solid mechanics finite element codes for 2D and 3D static analysis
JF  - International Journal for Numerical Methods in Engineering
N2  - Edge-based and face-based smoothed finite element methods (ES-FEM and FS-FEM, respectively) are modified versions of the finite element method allowing to achieve more accurate results and to reduce sensitivity to mesh distortion, at least for linear elements. These properties make the two methods very attractive. However, their implementation in a standard finite element code is nontrivial because it requires heavy and extensive modifications to the code architecture. In this article, we present an element-based formulation of ES-FEM and FS-FEM methods allowing to implement the two methods in a standard finite element code with no modifications to its architecture. Moreover, the element-based formulation permits to easily manage any type of element, especially in 3D models where, to the best of the authors' knowledge, only tetrahedral elements are used in FS-FEM applications found in the literature. Shape functions for non-simplex 3D elements are proposed in order to apply FS-FEM to any standard finite element.
KW  - distorted element
KW  - ES-FEM
KW  - FS-FEM
KW  - non-simplex S-FEM elements
KW  - S-FEM
Y1  - 2022
U6  - https://doi.org/10.1002/nme.7126
SN  - 1097-0207
VL  - 124
IS  - 2
SP  - 402
EP  - 433
PB  - Wiley
CY  - Chichester
ER  -