@incollection{KnottSofroniaGerressenetal.2014,
  author    = {Knott, Thomas C. and Sofronia, Raluca E. and Gerressen, Marcus and Law, Yuen and Davidescu, Arjana and Savii, George G. and Gatzweiler, Karl-Heinz and Staat, Manfred and Kuhlen, Torsten W.},
  title     = {Preliminary bone sawing model for a virtual reality-based training simulator of bilateral sagittal split osteotomy},
  series = {Biomedical simulation : 6th International Symposium, ISBMS 2014, Strasbourg, France, October 16-17, 2014 : proceedings (Lecture notes in computer science : vol. 8789)},
  booktitle = {Biomedical simulation : 6th International Symposium, ISBMS 2014, Strasbourg, France, October 16-17, 2014 : proceedings (Lecture notes in computer science : vol. 8789)},
  publisher = {Springer},
  address   = {Cham},
  isbn      = {978-3-319-12057-7 (Online)},
  doi       = {10.1007/978-3-319-12057-7_1},
  pages     = {1 -- 10},
  year      = {2014},
  abstract  = {Successful bone sawing requires a high level of skill and experience, which could be gained by the use of Virtual Reality-based simulators. A key aspect of these medical simulators is realistic force feedback. The aim of this paper is to model the bone sawing process in order to develop a valid training simulator for the bilateral sagittal split osteotomy, the most often applied corrective surgery in case of a malposition of the mandible. Bone samples from a human cadaveric mandible were tested using a designed experimental system. Image processing and statistical analysis were used for the selection of four models for the bone sawing process. The results revealed a polynomial dependency between the material removal rate and the applied force. Differences between the three segments of the osteotomy line and between the cortical and cancellous bone were highlighted.},
  language  = {en}
}
@article{PhamVuTranetal.2010,
  author    = {Pham, Phu Tinh and Vu, Khoi Duc and Tran, Thanh Ngoc and Staat, Manfred},
  title     = {A primal-dual algorithm for shakedown analysis of elastic-plastic bounded linearly kinematic hardening bodies},
  pages     = {1 -- 7},
  year      = {2010},
  language  = {en}
}
@article{NguyenRaatschenStaat2010,
  author    = {Nguyen, N.-H. and Raatschen, Hans-J{\"u}rgen and Staat, Manfred},
  title     = {A hyperelastic model of biological tissue materials in tubular organs},
  pages     = {1 -- 12},
  year      = {2010},
  language  = {en}
}
@article{BhattaraiStaat2018,
  author    = {Bhattarai, Aroj and Staat, Manfred},
  title     = {Modelling of Soft Connective Tissues to Investigate Female Pelvic Floor Dysfunctions},
  series = {Computational and Mathematical Methods in Medicine},
  volume    = {2018},
  journal   = {Computational and Mathematical Methods in Medicine},
  number    = {Article ID 9518076},
  publisher = {Hindawi},
  address   = {New York, NY},
  issn      = {1748-6718},
  doi       = {10.1155/2018/9518076},
  pages     = {1 -- 16},
  year      = {2018},
  abstract  = {After menopause, decreased levels of estrogen and progesterone remodel the collagen of the soft tissues thereby reducing their stiffness. Stress urinary incontinence is associated with involuntary urine leakage due to pathological movement of the pelvic organs resulting from lax suspension system, fasciae, and ligaments. This study compares the changes in the orientation and position of the female pelvic organs due to weakened fasciae, ligaments, and their combined laxity. A mixture theory weighted by respective volume fraction of elastin-collagen fibre compound (5\%), adipose tissue (85\%), and smooth muscle (5\%) is adopted to characterize the mechanical behaviour of the fascia. The load carrying response (other than the functional response to the pelvic organs) of each fascia component, pelvic organs, muscles, and ligaments are assumed to be isotropic, hyperelastic, and incompressible. Finite element simulations are conducted during Valsalva manoeuvre with weakened tissues modelled by reduced tissue stiffness. A significant dislocation of the urethrovesical junction is observed due to weakness of the fascia (13.89 mm) compared to the ligaments (5.47 mm). The dynamics of the pelvic floor observed in this study during Valsalva manoeuvre is associated with urethral-bladder hypermobility, greater levator plate angulation, and positive Q-tip test which are observed in incontinent females.},
  language  = {en}
}
@article{ColomboDriraFrotscheretal.2022,
  author    = {Colombo, Daniele and Drira, Slah and Frotscher, Ralf and Staat, Manfred},
  title     = {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},
  series = {International Journal for Numerical Methods in Engineering},
  volume    = {124},
  journal   = {International Journal for Numerical Methods in Engineering},
  number    = {2},
  publisher = {Wiley},
  address   = {Chichester},
  issn      = {1097-0207},
  doi       = {10.1002/nme.7126},
  pages     = {402 -- 433},
  year      = {2022},
  abstract  = {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.},
  language  = {en}
}
@article{NguyenDuongTranetal.2012,
  author    = {Nguyen, Nhu Huynh and Duong, Minh Tuan and Tran, Thanh Ngoc and Pham, Phu Tinh and Grottke, O. and Tolba, R. and Staat, Manfred},
  title     = {Influence of a freeze-thaw cycle on the stress-stretch curves of tissues of porcine abdominal organs},
  series = {Journal of Biomechanics},
  volume    = {45},
  journal   = {Journal of Biomechanics},
  number    = {14},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-2380},
  doi       = {10.1016/j.jbiomech.2012.07.008},
  pages     = {2382 -- 2386},
  year      = {2012},
  abstract  = {The paper investigates both fresh porcine spleen and liver and the possible decomposition of these organs under a freeze-thaw cycle. The effect of tissue preservation condition is an important factor which should be taken into account for protracted biomechanical tests. In this work, tension tests were conducted for a large number of tissue specimens from twenty pigs divided into two groups of 10. Concretely, the first group was tested in fresh state; the other one was tested after a freeze-thaw cycle which simulates the conservation conditions before biomechanical experiments. A modified Fung model for isotropic behavior was adopted for the curve fitting of each kind of tissues. Experimental results show strong effects of the realistic freeze-thaw cycle on the capsule of elastin-rich spleen but negligible effects on the liver which virtually contains no elastin. This different behavior could be explained by the autolysis of elastin by elastolytic enzymes during the warmer period after thawing. Realistic biomechanical properties of elastin-rich organs can only be expected if really fresh tissue is tested. The observations are supported by tests of intestines.},
  language  = {en}
}
@article{StaatTrenzLohmannetal.2012,
  author    = {Staat, Manfred and Trenz, Eva and Lohmann, Philipp and Frotscher, Ralf and Klinge, Uwe and Tabaza, Ruth and Kirschner-Hermanns, Ruth},
  title     = {New measurements to compare soft tissue anchoring systems in pelvic floor surgery},
  series = {Journal of Biomedical Materials Research Part B: Applied Biomaterials},
  volume    = {100B},
  journal   = {Journal of Biomedical Materials Research Part B: Applied Biomaterials},
  number    = {4},
  publisher = {Wiley},
  address   = {Hoboken, NJ},
  issn      = {1552-4981},
  doi       = {10.1002/jbm.b.32654},
  pages     = {924 -- 933},
  year      = {2012},
  abstract  = {Suburethral slings as well as different meshes are widely used treating stress urinary incontinence and prolaps in women. With the development of MiniSlings and special meshes using less alloplastic material anchorage systems become more important to keep devices in place and to put some tension especially on the MiniSlings. To date, there are many different systems of MiniSlings of different companies on the market which differ in the structure of the used meshes and anchors. A new objective measurement method to compare different properties of MiniSling systems (mesh and anchor) is presented in this article. Ballistic gelatine acts as soft tissue surrogate. Significant differences in parameters like pull-out strength of anchors or shrinkage of meshes under loading conditions have been determined. The form and size of the anchors as well as the structural stability of the meshes are decisive for a proper integration. The tested anchorings sytems showed markedly different mechanical function at their respective load bearing capacity. As the stable fixation of the device in tissue is a prerequisite for a permanet reinforcement, the proposed test system permits further optimisation of anchor and mesh devices to improve the success of the surgical treatment},
  language  = {en}
}
@article{NovacekTranKlingeetal.2012,
  author    = {Novacek, V. and Tran, Thanh Ngoc and Klinge, U. and Tolba, R. H. and Staat, Manfred and Bronson, D. G. and Miesse, A. M. and Whiffen, J. and Turquier, F.},
  title     = {Finite element modelling of stapled colorectal end-to-end anastomosis : Advantages of variable height stapler design},
  series = {Journal of Biomechanics},
  volume    = {45},
  journal   = {Journal of Biomechanics},
  number    = {115},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-2380},
  doi       = {10.1016/j.jbiomech.2012.07.021},
  pages     = {2693 -- 2697},
  year      = {2012},
  abstract  = {The impact of surgical staplers on tissues has been studied mostly in an empirical manner. In this paper, finite element method was used to clarify the mechanics of tissue stapling and associated phenomena. Various stapling modalities and several designs of circular staplers were investigated to evaluate the impact of the device on tissues and mechanical performance of the end-to-end colorectal anastomosis. Numerical simulations demonstrated that a single row of staples is not adequate to resist leakage due to non-linear buckling and opening of the tissue layers between two adjacent staples. Compared to the single staple row configuration, significant increase in stress experienced by the tissue at the inner staple rows was observed in two and three rows designs. On the other hand, adding second and/or third staple row had no effect on strain in the tissue inside the staples. Variable height design with higher staples in outer rows significantly reduced the stresses and strains in outer rows when compared to the same configuration with flat cartridge.},
  language  = {en}
}
@article{HacklWegmannKahmannetal.2017,
  author    = {Hackl, Michael and Wegmann, Kilian and Kahmann, Stephanie Lucina and Heinze, Nicolai and Staat, Manfred and Neiss, Wolfram F. and Scaal, Martin and M{\"u}ller, Lars P.},
  title     = {Radial shortening osteotomy reduces radiocapitellar contact pressures while preserving valgus stability of the elbow},
  series = {Knee Surgery, Sports Traumatology, Arthroscopy},
  volume    = {25},
  journal   = {Knee Surgery, Sports Traumatology, Arthroscopy},
  number    = {7},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1433-7347},
  doi       = {10.1007/s00167-017-4468-z},
  pages     = {2280 -- 2288},
  year      = {2017},
  language  = {en}
}
@article{StaatHeitzer2003,
  author    = {Staat, Manfred and Heitzer, M.},
  title     = {Probabilistic limit and shakedown problems},
  series = {Numerical Methods for Limit and Shakedown Analysis. Deterministic and Probabilistic Approach. NIC Series Vol. 15 / Ed. by Staat, M; Heitzer, M.},
  journal   = {Numerical Methods for Limit and Shakedown Analysis. Deterministic and Probabilistic Approach. NIC Series Vol. 15 / Ed. by Staat, M; Heitzer, M.},
  publisher = {John von Neumann Institute for Computing (NIC)},
  address   = {J{\"u}lich},
  isbn      = {3-00-010001-6},
  pages     = {217 -- 268},
  year      = {2003},
  language  = {en}
}
@article{HacklKahmannWegmannetal.2016,
  author    = {Hackl, Michael and Kahmann, Stephanie Lucina and Wegmann, Kilian and Ries, Christian and Staat, Manfred and M{\"u}ller, Lars-Peter},
  title     = {Shortening osteotomy of the proximal radius — a treatment option for isolated osteoarthritis of the lateral column of the elbow joint?},
  series = {Knee surgery, sports traumatology, arthroscopy},
  volume    = {Volume 24},
  journal   = {Knee surgery, sports traumatology, arthroscopy},
  number    = {Supplement 1},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {0942-2056},
  doi       = {10.1007/s00167-016-4080-7},
  pages     = {128 -- 129},
  year      = {2016},
  abstract  = {Treatment of posttraumatic osteoarthritis of the radial column of the elbow joint remains a challenging yet common issue. While partial joint replacement leads to high revision rates, radial head excision has shown to severely increase joint instability. Shortening osteotomy of the radius could be an option to decrease the contact pressure of the radiohumeral joint and thereby pain levels without causing valgus instability. Hence, the aim of this biomechanical study was to evaluate the effects of radial shortening on axial load distribution and valgus stability of the elbow joint.},
  language  = {en}
}
@article{Staat1993,
  author    = {Staat, Manfred},
  title     = {Reliability of the Primary Circuit Pressure Boundary of an HTR-Module under Accident Conditions},
  series = {Safety and reliability assessment : an integral approach ; ESREL'93 ; proceedings of the European Safety and Reliability Conference, Munich, Germany, May 10th - 12th 1993 / Kafka, P. [ed]},
  journal   = {Safety and reliability assessment : an integral approach ; ESREL'93 ; proceedings of the European Safety and Reliability Conference, Munich, Germany, May 10th - 12th 1993 / Kafka, P. [ed]},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {0-444-81561-9},
  pages     = {331 -- 342},
  year      = {1993},
  language  = {en}
}
@article{Staat2002,
  author    = {Staat, Manfred},
  title     = {Some Achievements of the European Project LISA for FEM Based Limit and Shakedown Analysis},
  series = {Computational mechanics : developments and applications, 2002 : presented at the 2002 ASME Pressure Vessels and Piping Conference, Vancouver, British Columbia, Canada, August 5 - 9. / Badie, N. [ed]},
  journal   = {Computational mechanics : developments and applications, 2002 : presented at the 2002 ASME Pressure Vessels and Piping Conference, Vancouver, British Columbia, Canada, August 5 - 9. / Badie, N. [ed]},
  publisher = {American Society of Mechanical Engineers},
  address   = {New York},
  isbn      = {0791846520},
  pages     = {177 -- 185},
  year      = {2002},
  language  = {en}
}
@article{StaatHeitzerReinersetal.2003,
  author    = {Staat, Manfred and Heitzer, M. and Reiners, H. and Schubert, F.},
  title     = {Shakedown and ratchetting under tension-torsion loadings: analysis and experiments},
  series = {Nuclear Engineering and Design. 225 (2003), H. 1},
  journal   = {Nuclear Engineering and Design. 225 (2003), H. 1},
  isbn      = {0029-5493},
  pages     = {11 -- 26},
  year      = {2003},
  language  = {en}
}
@incollection{StaatHeitzer2003,
  author    = {Staat, Manfred and Heitzer, M.},
  title     = {Basis reduction technique for limit and shakedown problems},
  series = {Numerical Methods for Limit and Shakedown Analysis. Deterministic and Probabilistic Approach. NIC Series Vol. 15 / Ed. by Staat, M.; Heitzer, M.},
  booktitle = {Numerical Methods for Limit and Shakedown Analysis. Deterministic and Probabilistic Approach. NIC Series Vol. 15 / Ed. by Staat, M.; Heitzer, M.},
  publisher = {John von Neumann Institute for Computing (NIC)},
  address   = {J{\"u}lich},
  isbn      = {3-00-010001-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:0001-2018112115},
  pages     = {1 -- 55},
  year      = {2003},
  language  = {en}
}
@article{MeyerGaalenLeschingeretal.2019,
  author    = {Meyer, Carolin and Gaalen, Kerstin van and Leschinger, Tim and Scheyerer, Max J. and Neiss, Wolfram F. and Staat, Manfred and M{\"u}ller, Lars P. and Wegmann, Kilian},
  title     = {Kyphoplasty of Osteoporotic Fractured Vertebrae: A Finite Element Analysis about Two Types of Cement},
  series = {BioMed Research International},
  journal   = {BioMed Research International},
  doi       = {10.1155/2019/9232813},
  pages     = {Article ID 9232813},
  year      = {2019},
  language  = {en}
}
@article{TranKreissigStaat2009,
  author    = {Tran, Thanh Ngoc and Kreißig, R. and Staat, Manfred},
  title     = {Probabilistic limit and shakedown analysis of thin plates and shells},
  series = {Structural safety. 31 (2009), H. 1},
  journal   = {Structural safety. 31 (2009), H. 1},
  publisher = {-},
  isbn      = {0167-4730},
  pages     = {1 -- 18},
  year      = {2009},
  language  = {en}
}
@article{StaatTranKreissig2008,
  author    = {Staat, Manfred and Tran, Thanh Ngoc and Kreißig, R.},
  title     = {Load bearing capacity of thin shell structures made of elastoplastic material by direct methods},
  series = {Technische Mechanik. 28 (2008), H. 3-4},
  journal   = {Technische Mechanik. 28 (2008), H. 3-4},
  pages     = {299 -- 309},
  year      = {2008},
  language  = {en}
}
@article{StaatBallmann1988,
  author    = {Staat, Manfred and Ballmann, J.},
  title     = {Wave Propagation and Focussing in Plates},
  series = {Impact loading and dynamic behaviour of materials : Papers presented at the International Conference on Impact Loading and Dynamic Behaviour of Materials, Vol. 2 / Chiem, C. Y.; Kunze, L. (u.a.) [eds]},
  journal   = {Impact loading and dynamic behaviour of materials : Papers presented at the International Conference on Impact Loading and Dynamic Behaviour of Materials, Vol. 2 / Chiem, C. Y.; Kunze, L. (u.a.) [eds]},
  publisher = {DGM Informationsges.},
  address   = {Oberursel},
  year      = {1988},
  language  = {en}
}
@article{TranPhamVuetal.2009,
  author    = {Tran, Thanh Ngoc and Pham, Phu Tinh and Vu, D. K. and Staat, Manfred},
  title     = {Reliability Analysis of Inelastic Shell Structures Under Variable Loads},
  series = {Limit States of Materials and Structures : Direct Methods / Hrsg. Dieter Weichert; Hrsg. Alan Ponter},
  journal   = {Limit States of Materials and Structures : Direct Methods / Hrsg. Dieter Weichert; Hrsg. Alan Ponter},
  publisher = {Springer Netherland},
  address   = {Berlin},
  isbn      = {978-1-4020-9633-4},
  pages     = {135 -- 156},
  year      = {2009},
  language  = {en}
}
@article{StaatHeitzer1999,
  author    = {Staat, Manfred and Heitzer, M.},
  title     = {Structural Reliability Analysis of Elasto-Plastic Structures},
  series = {Safety and reliability : proceedings of ESREL '99, the Tenth European Conference on Safety and Reliability, Munich-Garching, Germany, 13 - 17 September 1999 / Schu{\"e}ller, G. I.; Kafka, P. [eds]},
  journal   = {Safety and reliability : proceedings of ESREL '99, the Tenth European Conference on Safety and Reliability, Munich-Garching, Germany, 13 - 17 September 1999 / Schu{\"e}ller, G. I.; Kafka, P. [eds]},
  publisher = {Balkema},
  address   = {Rotterdam},
  isbn      = {90-5809-109-0},
  pages     = {513 -- 518},
  year      = {1999},
  language  = {en}
}
@inproceedings{TranStaat2021,
  author    = {Tran, Ngoc Trinh and Staat, Manfred},
  title     = {FEM shakedown analysis of Kirchhoff-Love plates under uncertainty of strength},
  series = {Proceedings of UNCECOMP 2021},
  booktitle = {Proceedings of UNCECOMP 2021},
  isbn      = {978-618-85072-6-5},
  doi       = {10.7712/120221.8041.19047},
  pages     = {323 -- 338},
  year      = {2021},
  abstract  = {A new formulation to calculate the shakedown limit load of Kirchhoff plates under stochastic conditions of strength is developed. Direct structural reliability design by chance con-strained programming is based on the prescribed failure probabilities, which is an effective approach of stochastic programming if it can be formulated as an equivalent deterministic optimization problem. We restrict uncertainty to strength, the loading is still deterministic. A new formulation is derived in case of random strength with lognormal distribution. Upper bound and lower bound shakedown load factors are calculated simultaneously by a dual algorithm.},
  language  = {en}
}
@article{HacklNacovKammerlohretal.2021,
  author    = {Hackl, Michael and Nacov, Julia and Kammerlohr, Sandra and Staat, Manfred and Buess, Eduard and Leschinger, Tim and M{\"u}ller, Lars P. and Wegmann, Kilian},
  title     = {Intratendinous Strain Variations of the Supraspinatus Tendon Depending on Repair Technique: A Biomechanical Analysis Regarding the Cause of Medial Cuff Failure},
  series = {The American Journal of Sports Medicine},
  volume    = {49},
  journal   = {The American Journal of Sports Medicine},
  number    = {7},
  publisher = {Sage},
  address   = {London},
  issn      = {1552-3365},
  doi       = {10.1177/03635465211006138},
  pages     = {1847 -- 1853},
  year      = {2021},
  language  = {en}
}
@article{HorbachStaatPerezVianaetal.2020,
  author    = {Horbach, Andreas and Staat, Manfred and Perez-Viana, Daniel and Simmen, Hans-Peter and Neuhaus, Valentin and Pape, Hans-Christoph and Prescher, Andreas and Ciritsis, Bernhard},
  title     = {Biomechanical in vitro examination of a standardized low-volume tubular femoroplasty},
  series = {Clinical Biomechanics},
  volume    = {80},
  journal   = {Clinical Biomechanics},
  number    = {Art. 105104},
  publisher = {Elsevier},
  address   = {Amsterdam},
  doi       = {10.1016/j.clinbiomech.2020.105104},
  year      = {2020},
  abstract  = {Background Osteoporosis is associated with the risk of fractures near the hip. Age and comorbidities increase the perioperative risk. Due to the ageing population, fracture of the proximal femur also proves to be a socio-economic problem. Preventive surgical measures have hardly been used so far. Methods 10 pairs of human femora from fresh cadavers were divided into control and low-volume femoroplasty groups and subjected to a Hayes fall-loading fracture test. The results of the respective localization and classification of the fracture site, the Singh index determined by computed tomography (CT) examination and the parameters in terms of fracture force, work to fracture and stiffness were evaluated statistically and with the finite element method. In addition, a finite element parametric study with different position angles and variants of the tubular geometry of the femoroplasty was performed. Findings Compared to the control group, the work to fracture could be increased by 33.2\%. The fracture force increased by 19.9\%. The used technique and instrumentation proved to be standardized and reproducible with an average poly(methyl methacrylate) volume of 10.5 ml. The parametric study showed the best results for the selected angle and geometry. Interpretation The cadaver studies demonstrated the biomechanical efficacy of the low-volume tubular femoroplasty. The numerical calculations confirmed the optimal choice of positioning as well as the inner and outer diameter of the tube in this setting. The standardized minimally invasive technique with the instruments developed for it could be used in further comparative studies to confirm the measured biomechanical results.},
  language  = {en}
}
@article{KnoxBruggemannGossmannetal.2020,
  author    = {Knox, Ronald and Bruggemann, Andrea and Gossmann, Matthias and Thomas, Ulrich and Horv{\´a}th, Andr{\´a}s and Dragicevic, Elena and Stoelzle-Feix, Sonja and Fertig, Niels and Jung, Alexander and Raman, Aravind Hariharan and Staat, Manfred and Linder, Peter},
  title     = {Combining physiological relevance and throughput for in vitro cardiac contractility measurement},
  series = {Biophysical Journal},
  volume    = {118},
  journal   = {Biophysical Journal},
  number    = {Issue 3, Supplement 1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0006-3495},
  doi       = {10.1016/j.bpj.2019.11.3104},
  pages     = {570a},
  year      = {2020},
  abstract  = {Despite increasing acceptance of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in safety pharmacology, controversy remains about the physiological relevance of existing in vitro models for their mechanical testing. We hypothesize that existing signs of immaturity of the cell models result from an improper mechanical environment. We cultured hiPSC-CMs in a 96-well format on hyperelastic silicone membranes imitating their native mechanical environment, resulting in physiological responses to compound stimuli.We validated cell responses on the FLEXcyte 96, with a set of reference compounds covering a broad range of cellular targets, including ion channel modulators, adrenergic receptor modulators and kinase inhibitors. Acute (10 - 30 min) and chronic (up to 7 days) effects were investigated. Furthermore, the measurements were complemented with electromechanical models based on electrophysiological recordings of the used cell types.hiPSC-CMs were cultured on freely-swinging, ultra-thin and hyperelastic silicone membranes. The weight of the cell culture medium deflects the membranes downwards. Rhythmic contraction of the hiPSC-CMs resulted in dynamic deflection changes which were quantified by capacitive distance sensing. The cells were cultured for 7 days prior to compound addition. Acute measurements were conducted 10-30 minutes after compound addition in standard culture medium. For chronic treatment, compound-containing medium was replaced daily for up to 7 days. Electrophysiological properties of the employed cell types were recorded by automated patch-clamp (Patchliner) and the results were integrated into the electromechanical model of the system.Calcium channel agonist S Bay K8644 and beta-adrenergic stimulator isoproterenol induced significant positive inotropic responses without additional external stimulation. Kinase inhibitors displayed cardiotoxic effects on a functional level at low concentrations. The system-integrated analysis detected alterations in beating shape as well as frequency and arrhythmic events and we provide a quantitative measure of these.},
  language  = {en}
}
@article{TranStaat2021,
  author    = {Tran, Ngoc Trinh and Staat, Manfred},
  title     = {Direct plastic structural design under random strength and random load by chance constrained programming},
  series = {European Journal of Mechanics - A/Solids},
  volume    = {85},
  journal   = {European Journal of Mechanics - A/Solids},
  number    = {Article 104106},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0997-7538},
  doi       = {10.1016/j.euromechsol.2020.104106},
  year      = {2021},
  language  = {en}
}
@article{BhattaraiMayStaatetal.2022,
  author    = {Bhattarai, Aroj and May, Charlotte Anabell and Staat, Manfred and Kowalczyk, Wojciech and Tran, Thanh Ngoc},
  title     = {Layer-specific damage modeling of porcine large intestine under biaxial tension},
  series = {Bioengineering},
  volume    = {9},
  journal   = {Bioengineering},
  number    = {10, Early Access},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2306-5354},
  doi       = {10.3390/bioengineering9100528},
  pages     = {1 -- 17},
  year      = {2022},
  abstract  = {The mechanical behavior of the large intestine beyond the ultimate stress has never been investigated. Stretching beyond the ultimate stress may drastically impair the tissue microstructure, which consequently weakens its healthy state functions of absorption, temporary storage, and transportation for defecation. Due to closely similar microstructure and function with humans, biaxial tensile experiments on the porcine large intestine have been performed in this study. In this paper, we report hyperelastic characterization of the large intestine based on experiments in 102 specimens. We also report the theoretical analysis of the experimental results, including an exponential damage evolution function. The fracture energies and the threshold stresses are set as damage material parameters for the longitudinal muscular, the circumferential muscular and the submucosal collagenous layers. A biaxial tensile simulation of a linear brick element has been performed to validate the applicability of the estimated material parameters. The model successfully simulates the biomechanical response of the large intestine under physiological and non-physiological loads.},
  language  = {en}
}
@article{PhamStaat2014,
  author    = {Pham, Phu Tinh and Staat, Manfred},
  title     = {FEM-based shakedown analysis of hardening structures},
  series = {Asia Pacific journal on computational engineering},
  journal   = {Asia Pacific journal on computational engineering},
  number    = {1},
  publisher = {SpringerOpen},
  address   = {Berlin},
  issn      = {2196-1166 (E-Journal)},
  doi       = {10.1186/2196-1166-1-4},
  pages     = {Article No. 4},
  year      = {2014},
  abstract  = {This paper develops a new finite element method (FEM)-based upper bound algorithm for limit and shakedown analysis of hardening structures by a direct plasticity method. The hardening model is a simple two-surface model of plasticity with a fixed bounding surface. The initial yield surface can translate inside the bounding surface, and it is bounded by one of the two equivalent conditions: (1) it always stays inside the bounding surface or (2) its centre cannot move outside the back-stress surface. The algorithm gives an effective tool to analyze the problems with a very high number of degree of freedom. Our numerical results are very close to the analytical solutions and numerical solutions in literature.},
  language  = {en}
}
@inproceedings{PhamStaat2015,
  author    = {Pham, Phu Tinh and Staat, Manfred},
  title     = {A simplification for shakedown analysis of hardening structures},
  series = {Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon},
  booktitle = {Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon},
  publisher = {RWTH Aachen University},
  address   = {Aachen},
  organization    = {ECCOMAS Young Investigators Conference <3, 2015, Aachen>},
  pages     = {1 -- 4},
  year      = {2015},
  language  = {en}
}
@article{CiritsisHorbachStaatetal.2018,
  author    = {Ciritsis, Alexander and Horbach, Andreas and Staat, Manfred and Kuhl, Christiane K. and Kraemer, Nils Andreas},
  title     = {Porosity and tissue integration of elastic mesh implants evaluated in vitro and in vivo},
  series = {Journal of Biomedical Materials Research: Part B: Applied Biomaterials},
  volume    = {106},
  journal   = {Journal of Biomedical Materials Research: Part B: Applied Biomaterials},
  number    = {2},
  publisher = {Wiley},
  address   = {New York, NY},
  issn      = {1552-4981},
  doi       = {10.1002/jbm.b.33877},
  pages     = {827 -- 833},
  year      = {2018},
  abstract  = {Purpose In vivo, a loss of mesh porosity triggers scar tissue formation and restricts functionality. The purpose of this study was to evaluate the properties and configuration changes as mesh deformation and mesh shrinkage of a soft mesh implant compared with a conventional stiff mesh implant in vitro and in a porcine model. Material and Methods Tensile tests and digital image correlation were used to determine the textile porosity for both mesh types in vitro. A group of three pigs each were treated with magnetic resonance imaging (MRI) visible conventional stiff polyvinylidene fluoride meshes (PVDF) or with soft thermoplastic polyurethane meshes (TPU) (FEG Textiltechnik mbH, Aachen, Germany), respectively. MRI was performed with a pneumoperitoneum at a pressure of 0 and 15 mmHg, which resulted in bulging of the abdomen. The mesh-induced signal voids were semiautomatically segmented and the mesh areas were determined. With the deformations assessed in both mesh types at both pressure conditions, the porosity change of the meshes after 8 weeks of ingrowth was calculated as an indicator of preserved elastic properties. The explanted specimens were examined histologically for the maturity of the scar (collagen I/III ratio). Results In TPU, the in vitro porosity increased constantly, in PVDF, a loss of porosity was observed under mild stresses. In vivo, the mean mesh areas of TPU were 206.8 cm2 (± 5.7 cm2) at 0 mmHg pneumoperitoneum and 274.6 cm2 (± 5.2 cm2) at 15 mmHg; for PVDF the mean areas were 205.5 cm2 (± 8.8 cm2) and 221.5 cm2 (± 11.8 cm2), respectively. The pneumoperitoneum-induced pressure increase resulted in a calculated porosity increase of 8.4\% for TPU and of 1.2\% for PVDF. The mean collagen I/III ratio was 8.7 (± 0.5) for TPU and 4.7 (± 0.7) for PVDF. Conclusion The elastic properties of TPU mesh implants result in improved tissue integration compared to conventional PVDF meshes, and they adapt more efficiently to the abdominal wall. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 827-833, 2018.},
  language  = {en}
}
@misc{HacklWegmannKahmannetal.2017,
  author    = {Hackl, Michael and Wegmann, Kilian and Kahmann, Stephanie Lucina and Heinze, Nicolai and Staat, Manfred and Neiss, Wolfram F. and Scaal, Martin and M{\"u}ller, Lars P.},
  title     = {Reply to the letter to the editor: shortening osteotomy of the proximal radius},
  series = {Knee Surgery, Sports Traumatology, Arthroscopy},
  volume    = {25},
  journal   = {Knee Surgery, Sports Traumatology, Arthroscopy},
  number    = {10},
  doi       = {10.1007/s00167-017-4666-8},
  pages     = {3328 -- 3329},
  year      = {2017},
  language  = {en}
}
@inproceedings{TranMatthiesStavroulakisetal.2018,
  author    = {Tran, Ngoc Trinh and Matthies, Hermann G. and Stavroulakis, Georgios Eleftherios and Staat, Manfred},
  title     = {Direct plastic structural design by chance constrained programming},
  series = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK},
  booktitle = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK},
  pages     = {12 Seiten},
  year      = {2018},
  abstract  = {We propose a stochastic programming method to analyse limit and shakedown of structures under random strength with lognormal distribution. In this investigation a dual chance constrained programming algorithm is developed to calculate simultaneously both the upper and lower bounds of the plastic collapse limit or the shakedown limit. The edge-based smoothed finite element method (ES-FEM) using three-node linear triangular elements is used.},
  language  = {en}
}
@article{StaatHeitzerLangetal.2005,
  author    = {Staat, Manfred and Heitzer, M. and Lang, H. and Wirtz, K.},
  title     = {Direct Finite Element Route for Design-by-Analysis of Pressure Components},
  series = {International Journal of Pressure Vessels and Piping. 82 (2005), H. 1},
  journal   = {International Journal of Pressure Vessels and Piping. 82 (2005), H. 1},
  isbn      = {0308-0161},
  pages     = {61 -- 67},
  year      = {2005},
  language  = {en}
}
@inproceedings{DuongNguyenStaat2012,
  author    = {Duong, Minh Tuan and Nguyen, Nhu Huynh and Staat, Manfred},
  title     = {Numerical stability enhancement of modeling hyperelastic materials},
  series = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  booktitle = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  editor    = {Eberhardsteiner, J.},
  year      = {2012},
  language  = {en}
}
@article{HacklAndermahrStaatetal.2017,
  author    = {Hackl, M. and Andermahr, J. and Staat, Manfred and Bremer, I. and Borggrefe, J. and Prescher, A. and M{\"u}ller, L. P. and Wegmann, K.},
  title     = {Suture button reconstruction of the central band of the interosseous membrane in Essex-Lopresti lesions: a comparative biomechanical investigation},
  series = {The Journal of Hand Surgery (European Volume)},
  volume    = {42},
  journal   = {The Journal of Hand Surgery (European Volume)},
  number    = {4},
  publisher = {Sage},
  address   = {London},
  issn      = {2043-6289 (Online)},
  doi       = {10.1177/1753193416665943},
  pages     = {370 -- 376},
  year      = {2017},
  language  = {en}
}
@article{TopcuMadabhushiStaat2022,
  author    = {Top{\c{c}}u, Murat and Madabhushi, Gopal S.P. and Staat, Manfred},
  title     = {A generalized shear-lag theory for elastic stress transfer between matrix and fibres having a variable radius},
  series = {International Journal of Solids and Structures},
  volume    = {239-240},
  journal   = {International Journal of Solids and Structures},
  number    = {Art. No. 111464},
  publisher = {Elsevier},
  address   = {New York, NY},
  issn      = {0020-7683},
  doi       = {10.1016/j.ijsolstr.2022.111464},
  year      = {2022},
  abstract  = {A generalized shear-lag theory for fibres with variable radius is developed to analyse elastic fibre/matrix stress transfer. The theory accounts for the reinforcement of biological composites, such as soft tissue and bone tissue, as well as for the reinforcement of technical composite materials, such as fibre-reinforced polymers (FRP). The original shear-lag theory proposed by Cox in 1952 is generalized for fibres with variable radius and with symmetric and asymmetric ends. Analytical solutions are derived for the distribution of axial and interfacial shear stress in cylindrical and elliptical fibres, as well as conical and paraboloidal fibres with asymmetric ends. Additionally, the distribution of axial and interfacial shear stress for conical and paraboloidal fibres with symmetric ends are numerically predicted. The results are compared with solutions from axisymmetric finite element models. A parameter study is performed, to investigate the suitability of alternative fibre geometries for use in FRP.},
  language  = {en}
}
@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}
}
@article{AbelKahmannMellonetal.2020,
  author    = {Abel, Alexander and Kahmann, Stephanie Lucina and Mellon, Stephen and Staat, Manfred and Jung, Alexander},
  title     = {An open-source tool for the validation of finite element models using three-dimensional full-field measurements},
  series = {Medical Engineering \& Physics},
  volume    = {77},
  journal   = {Medical Engineering \& Physics},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1350-4533},
  doi       = {10.1016/j.medengphy.2019.10.015},
  pages     = {125 -- 129},
  year      = {2020},
  abstract  = {Three-dimensional (3D) full-field measurements provide a comprehensive and accurate validation of finite element (FE) models. For the validation, the result of the model and measurements are compared based on two respective point-sets and this requires the point-sets to be registered in one coordinate system. Point-set registration is a non-convex optimization problem that has widely been solved by the ordinary iterative closest point algorithm. However, this approach necessitates a good initialization without which it easily returns a local optimum, i.e. an erroneous registration. The globally optimal iterative closest point (Go-ICP) algorithm has overcome this drawback and forms the basis for the presented open-source tool that can be used for the validation of FE models using 3D full-field measurements. The capability of the tool is demonstrated using an application example from the field of biomechanics. Methodological problems that arise in real-world data and the respective implemented solution approaches are discussed.},
  language  = {en}
}
@inproceedings{KahmannUschokWegmannetal.2018,
  author    = {Kahmann, Stephanie Lucina and Uschok, Stephan and Wegmann, Kilian and M{\"u}ller, Lars-P. and Staat, Manfred},
  title     = {Biomechanical multibody model with refined kinematics of the elbow},
  series = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK},
  booktitle = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK},
  pages     = {11 Seiten},
  year      = {2018},
  abstract  = {The overall objective of this study is to develop a new external fixator, which closely maps the native kinematics of the elbow to decrease the joint force resulting in reduced rehabilitation time and pain. An experimental setup was designed to determine the native kinematics of the elbow during flexion of cadaveric arms. As a preliminary study, data from literature was used to modify a published biomechanical model for the calculation of the joint and muscle forces. They were compared to the original model and the effect of the kinematic refinement was evaluated. Furthermore, the obtained muscle forces were determined in order to apply them in the experimental setup. The joint forces in the modified model differed slightly from the forces in the original model. The muscle force curves changed particularly for small flexion angles but their magnitude for larger angles was consistent.},
  language  = {en}
}
@article{AndingTabazaStaatetal.2013,
  author    = {Anding, Ralf and Tabaza, Ruth and Staat, Manfred and Trenz, Eva and Lohmann, Philipp and Klinge, Uwe and Kirschner-Hermanns, Ruth},
  title     = {Introducing a method of in vitro testing of different anchoring systems used for female incontinence and prolapse surgery},
  series = {BioMed research international},
  volume    = {Vol. 2013},
  journal   = {BioMed research international},
  issn      = {1110-7251 (E-Journal); 2314-6141 (E-Journal); 1110-7243 (Print); 2314-6133 (Print)},
  pages     = {Article ID 401417},
  year      = {2013},
  language  = {en}
}
@article{HacklLeschingerStaatetal.2016,
  author    = {Hackl, Michael and Leschinger, T. and Staat, Manfred and M{\"u}ller, Lars-Peter and Wegmann, Kilian},
  title     = {Reconstruction of the interosseous membrane in the Essex Lopresti lesion — a biomechanical evaluation},
  series = {Knee surgery, sports traumatology, arthroscopy},
  volume    = {Volume 24},
  journal   = {Knee surgery, sports traumatology, arthroscopy},
  number    = {Supplement 1},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {0942-2056},
  doi       = {10.1007/s00167-016-4080-7},
  pages     = {130 -- 131},
  year      = {2016},
  abstract  = {Surgical reconstruction of the interosseous membrane (IOM) could restore longitudinal forearm stability to avoid persisting disability due to capituloradial and ulnocarpal impingement in Essex Lopresti lesions. This biomechanical study aimed to assess longitudinal forearm stability of intact specimens, after sectioning of the IOM and after reconstruction with a TightRope construct using either a single or double bundle technique.},
  language  = {en}
}
@inproceedings{BhattaraiFrotscherStaat2015,
  author    = {Bhattarai, Aroj and Frotscher, Ralf and Staat, Manfred},
  title     = {Biomechanical study of the female pelvic floor dysfunction using the finite element method},
  series = {Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon},
  booktitle = {Conference proceedings of the YIC GACM 2015 : 3rd ECCOMAS Young Investigators Conference and 6th GACM Colloquium on Computational Mechanics , Aachen , Germany, 20.07.2015 - 23.07.2015 / ed.: Stefanie Elgeti ; Jaan-Willem Simon},
  publisher = {RWTH Aachen University},
  address   = {Aachen},
  organization    = {ECCOMAS Young Investigators Conference <3, 2015, Aachen>},
  pages     = {1 -- 4},
  year      = {2015},
  language  = {en}
}
@misc{JungMuellerStaat2021,
  author    = {Jung, Alexander and M{\"u}ller, Wolfram and Staat, Manfred},
  title     = {Corrigendum to "Wind and fairness in ski jumping: A computer modelling analysis" [J. Biomech. 75 (2018) 147-153]},
  series = {Journal of Biomechanics},
  volume    = {128},
  journal   = {Journal of Biomechanics},
  number    = {Article number: 110690},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0021-9290},
  doi       = {10.1016/j.jbiomech.2021.110690},
  pages     = {1 Seite},
  year      = {2021},
  language  = {en}
}
@incollection{BhattaraiFrotscherStaat2018,
  author    = {Bhattarai, Aroj and Frotscher, Ralf and Staat, Manfred},
  title     = {Computational Analysis of Pelvic Floor Dysfunction},
  series = {Women's Health and Biomechanics},
  booktitle = {Women's Health and Biomechanics},
  publisher = {Springer},
  address   = {Cham},
  isbn      = {978-3-319-71574-2},
  doi       = {10.1007/978-3-319-71574-2_17},
  pages     = {217 -- 230},
  year      = {2018},
  abstract  = {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.},
  language  = {en}
}
@article{WegmannHacklStaatetal.2016,
  author    = {Wegmann, Kilian and Hackl, Michael and Staat, Manfred and Mayer, Katharina and M{\"u}ller, Lars-Peter},
  title     = {Double plate osteosynthesis of proximal ulna fractures: biomechanical and clinical results},
  series = {Knee surgery, sports traumatology, arthroscopy},
  volume    = {Volume 24},
  journal   = {Knee surgery, sports traumatology, arthroscopy},
  number    = {Supplement 1},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {0942-2056},
  doi       = {10.1007/s00167-016-4079-0},
  pages     = {58 -- 59},
  year      = {2016},
  abstract  = {While plate fixation of proximal ulna fractures might lead to superior clinical results compared to tension band wiring, regular plates represent an established risk factor for wound complications. The olecranon double plates (Medartis, Basel, CH) might decrease complications related to the osteosynthesis because of their low profile and better anatomical fit. This study aimed to evaluate the biomechanical performance and clinical results of the olecranon double plates.},
  language  = {en}
}
@article{JungStaatMueller2013,
  author    = {Jung, Alexander and Staat, Manfred and M{\"u}ller, Wolfram},
  title     = {Flight style optimization in ski jumping on normal, large, and ski flying hills},
  series = {Journal of biomechanics},
  volume    = {Vol. 47},
  journal   = {Journal of biomechanics},
  number    = {Iss. 3},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-2380 (E-Journal); 0021-9290 (Print)},
  pages     = {716 -- 722},
  year      = {2013},
  language  = {en}
}
@article{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     = {FEM shakedown analysis of structures under random strength with chance constrained programming},
  series = {Vietnam Journal of Mechanics},
  volume    = {44},
  journal   = {Vietnam Journal of Mechanics},
  number    = {4},
  publisher = {Vietnam Academy of Science and Technology (VAST)},
  issn      = {0866-7136},
  doi       = {10.15625/0866-7136/17943},
  pages     = {459 -- 473},
  year      = {2022},
  abstract  = {Direct methods, comprising limit and shakedown analysis, are a branch of computational mechanics. They play a significant role in mechanical and civil engineering design. The concept of direct methods aims to determine the ultimate load carrying capacity of structures beyond the elastic range. In practical problems, the direct methods lead to nonlinear convex optimization problems with a large number of variables and constraints. If strength and loading are random quantities, the shakedown analysis can be formulated as stochastic programming problem. In this paper, a method called chance constrained programming is presented, which is an effective method of stochastic programming to solve shakedown analysis problems under random conditions of strength. In this study, the loading is deterministic, and the strength is a normally or lognormally distributed variable.},
  language  = {en}
}
@inproceedings{TranTranMatthiesetal.2016,
  author    = {Tran, Ngoc Trinh and Tran, Thanh Ngoc and Matthies, H. G. and Stavroulakis, G. E. and Staat, Manfred},
  title     = {Shakedown analysis of plate bending analysis under stochastic uncertainty by chance constrained programming},
  series = {ECCOMAS Congress 2016, VII European Congress on Computational Methods in Applied Sciences and Engineering. Crete Island, Greece, 5-10 June 2016},
  booktitle = {ECCOMAS Congress 2016, VII European Congress on Computational Methods in Applied Sciences and Engineering. Crete Island, Greece, 5-10 June 2016},
  editor    = {Papadrakakis, M.},
  pages     = {13 S.},
  year      = {2016},
  language  = {en}
}
@article{TranStaat2013,
  author    = {Tran, Thanh Ngoc and Staat, Manfred},
  title     = {An Edge-Based Smoothed Finite Element Method for Primal-Dual Shakedown Analysis of Structures Under Uncertainties},
  series = {Limit State of Materials and Structures : Direct Methods 2. Saxc{\´e}, G{\´e}ry de (Hrsg.)},
  journal   = {Limit State of Materials and Structures : Direct Methods 2. Saxc{\´e}, G{\´e}ry de (Hrsg.)},
  publisher = {Springer},
  address   = {Dordrecht},
  isbn      = {978-94-007-5424-9},
  pages     = {89 -- 102},
  year      = {2013},
  language  = {en}
}
@article{HasanKeilStaatetal.2012,
  author    = {Hasan, Istabrak and Keil, Ludger and Staat, Manfred and Wahl, Gerhard and Bourauel, Christoph},
  title     = {Determination of the frictional coefficient of the implant-antler interface : experimental approach},
  series = {Biomedical Engineering / Biomedizinische Technik},
  volume    = {57},
  journal   = {Biomedical Engineering / Biomedizinische Technik},
  number    = {5},
  publisher = {De Gruyter},
  address   = {Berlin},
  issn      = {1862-278X},
  pages     = {359 -- 363},
  year      = {2012},
  abstract  = {The similar bone structure of reindeer antler to human bone permits studying the osseointegration of dental implants in the jawbone. As the friction is one of the major factors that have a significant influence on the initial stability of immediately loaded dental implants, it is essential to define the frictional coefficient of the implant-antler interface. In this study, the kinetic frictional forces at the implant-antler interface were measured experimentally using an optomechanical setup and a stepping motor controller under different axial loads and sliding velocities. The corresponding mean values of the static and kinetic frictional coefficients were within the range of 0.5-0.7 and 0.3-0.5, respectively. An increase in the frictional forces with increasing applied axial loads was registered. The measurements showed an evidence of a decrease in the magnitude of the frictional coefficient with increasing sliding velocity. The results of this study provide a considerable assessment to clarify the suitable frictional coefficient to be used in the finite element contact analysis of antler specimens.},
  language  = {en}
}