Wyniki wyszukiwania - Biblioteka Nauki

1

Analiza numeryczna ceglanej kopuły zabytkowego kościoła

100%

Łodygowski T. , Wierszycki M.

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tom R. 58, nr 7

352-356

PL

W analizie uwzględniono charakterystykę geometryczną kopuły uzyskaną na podstawie pomiarów geodezyjnych. Szczególną uwagę zwrócono na modelowanie elementów kopuły murowanej, wykazujących rysy i pęknięcia. Przeprowadzona analiza umożliwiła jakościową ocenę zachowania się konstrukcji.

EN

The geometric characteristic of the cupola after geodetic measurement was settled and used in the analysis. In modelling the cupola special attention was paid to existing cracks and fractures of construction. The analysis done gave chance to elaborate qualitative estimation of safety for the construction analysed.

2

Numeryczna analiza wytrzymałościowa wszczepów uzębienia

100%

Wierszycki M. , Łodygowski T.

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tom nr 10

38-44

PL

W leczeniu ubytków uzębienia z zastosowaniem tytanowych implantów stomatologicznych obserwuje się powikłania o charakterze mechanicznym. Celem analiz numerycznych implantów z zastosowaniem MES było określenie przyczyny występowania powikłań oraz zaproponowanie rozwiązań pozwalających na ich unikanie, możliwych do zastosowania w praktyce stomatologicznej oraz w procesie projektowania implantów.

EN

Various mechanical complications can be obsen/ed in a treatment technique performed with the use of titanium implants. The main goal of the presented study was to find out the reasons of the complications and to suggest how to avoid them. Complex FE analysis proced:"res, which can be used in dental implants designing and manufacturing processes, were devised. The practical conclusions and recommendations for dental surgeons were formulated as well.

3

Numerical verification of two-component dental implant in the context of fatigue life for various load cases

100%

Szajek K. , Wierszycki M.

Acta of Bioengineering and Biomechanics

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2016

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tom Vol. 18, no. 1

103--113

EN

Purpose: Dental implant designing is a complex process which considers many limitations both biological and mechanical in nature. In earlier studies, a complete procedure for improvement of two-component dental implant was proposed. However, the optimization tasks carried out required assumption on representative load case, which raised doubts on optimality for the other load cases. This paper deals with verification of the optimal design in context of fatigue life and its main goal is to answer the question if the assumed load scenario (solely horizontal occlusal load) leads to the design which is also “safe” for oblique occlussal loads regardless the angle from an implant axis. Methods: The verification is carried out with series of finite element analyses for wide spectrum of physiologically justified loads. The design of experiment methodology with full factorial technique is utilized. All computations are done in Abaqus suite. Results: The maximal Mises stress and normalized effective stress amplitude for various load cases are discussed and compared with the assumed “safe” limit (equivalent of fatigue life for 5e6 cycles). Conclusions: The obtained results proof that coronial-appical load component should be taken into consideration in the two component dental implant when fatigue life is optimized. However, its influence in the analyzed case is small and does not change the fact that the fatigue life improvement is observed for all components within whole range of analyzed loads.

4

Fatigue algorithm for dental implant

80%

Wierszycki M. , Kąkol W. , Łodygowski T.

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tom No. 7

363-380

EN

Restorations with the application of implants are effective and commonly used in dental treatment. The computer simulation of implant fatigue life employing FEA is considered in the paper. For the simulation of implant structure behavior a 3D model including a spiral thread is applied, which allows for the full simulation of the kinematics of the implant, describing the multiaxial state of stress and, in consequence, the possibility of screw loosening. The cyclic scheme of the physiological occlusal loading and fatigue changes of dental material, bone loss phenomenon and changeability of boundary conditions are investigated. The valuable results for fatigue life which may be applied in modern prosthodontics are presented.

5

Three-dimensional nonlinear finite element model of lumbar intervertebral disc

80%

Lodygowski T. , Kąkol W. , Wierszycki M. , Ogurkowska M.

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2005

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tom Vol. 7, nr 2

29-37

EN

The main objective of this study is to model a three-dimensional nonlinear finite-element vertebra disc, which can be used in further simulation of human lumbar spinal segments in surgery, analyses of spinal equilibrium and stability. Because of complexity of modelling it is proposed to cary* out analyses on the simplified model built in such a way that the nonlinear response of the disc is replaced by a spring-type behaviour whose characteristics are obtained by computer simulations of an isolated disc. The geometry data of a human lumbar spinal segment, including a disc, is acquired from the computer tomography or magnetic nuclear resonance measurements, and a CAD model is designed and imported into FEA program. The simplified model was validated for loading schemes, including axial compression, bending and torsion acting on the spinal L4-L5 segment. Two models of intervertebra disc are shown and theirs advantages and accuracy are discussed.

6

Three-dimensional nonlinear finite element model of the human lumbar spine segment

80%

Lodygowski T. , Kąkol W. , Wierszycki M. , Ogurkowska M.

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2005

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tom Vol. 7, nr 2

17-28

EN

The objective of this paper is a three-dimensional modelling of vertebral segment (L4-L5), which can be used for numerical simulation of surgery, analysis of spinal equilibrium and stability. Because of the extreme complexity of finite element modelling we propose to carry out analyses on the simplified model. The geometry of vertebrae is known due to the computer tomography (CT) or nuclear magnetic resonance (NMR). CAD model is built and then imported into FEA program. The model under consideration, i.e. the model of spinal segment, consists of two bones and an intervertebral disc. The mechanical properties of tissues, boundary/interaction conditions and loadings accepted for computations are based on the literature and our own studies. The simplified model was proposed, developed and validated for several loading schemes, including axial compression, bending and torsion.