Making Logical Positivism Less Logical: The Case of Schlick and von Mises

The article asks which human qualities can serve as the base for a liberal economic policy. The author is looking for an answer to this question in the classical works of economic liberalism - in the books by F. Bastiat, L. von Mises, F. von Hayek, W. Eucken, and M. Friedman. The two main qualities can be summarized as follows: the relatively high rank of freedom among human values and rational utilitarian calculus. It is assumed that in those countries where the both human prerequisites are present the liberal policy (for instance, liberal reforms) can be self-supportive and may have good results. On the contrary, if the first prerequisite is missing and a liberal policy can be based only on rational calculus, the “paternalistic” liberalism prevails and chances for success are much smaller.

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Effects of occlusal scheme on All-on-Four abutments, screws and prostheses: A three-dimensional finite element study

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-19-00334 ◽

2020 ◽

Author(s):

Nurullah Türker ◽

Hümeyra Tercanlı Alkış ◽

Steven J Sadowsky ◽

Ulviye Şebnem Büyükkaplan

Keyword(s):

Finite Element ◽

Three Dimensional ◽

Good Prognosis ◽

Von Mises Stress ◽

Element Analysis ◽

Group Function ◽

Occlusal Contact ◽

Maximum Deformation ◽

Contact Points ◽

Von Mises

An ideal occlusal scheme plays an important role in a good prognosis of All-on-Four applications, as it does for other implant therapies, due to the potential impact of occlusal loads on implant prosthetic components. The aim of the present three-dimensional (3D) finite element analysis (FEA) study was to investigate the stresses on abutments, screws and prostheses that are generated by occlusal loads via different occlusal schemes in the All-on-Four concept. Three-dimensional models of the maxilla, mandible, implants, implant substructures and prostheses were designed according to the All-on-Four concept. Forces were applied from the occlusal contact points formed in maximum intercuspation and eccentric movements in canine guidance occlusion (CGO), group function occlusion (GFO) and lingualized occlusion (LO). The von Mises stress values for abutment and screws and deformation values for prostheses were obtained and results were evaluated comparatively. It was observed that the stresses on screws and abutments were more evenly distributed in GFO. Maximum deformation values for prosthesis were observed in the CFO model for lateral movement both in the maxilla and mandible. Within the limits of the present study, GFO may be suggested to reduce stresses on screws, abutments and prostheses in the All-on-Four concept.

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The Influence of Loading Position in A Priori High Stress Detection using Mode Superposition

Reports in Mechanical Engineering ◽

10.31181/rme200101093s ◽

2020 ◽

Vol 1 (1) ◽

pp. 93-102

Author(s):

Carsten Strzalka ◽

◽

Manfred Zehn ◽

Keyword(s):

Finite Element ◽

Degrees Of Freedom ◽

Equations Of Motion ◽

A Priori ◽

High Stress ◽

Von Mises Stress ◽

Detailed Knowledge ◽

Variable Loading ◽

Numerical Effort ◽

Von Mises

For the analysis of structural components, the finite element method (FEM) has become the most widely applied tool for numerical stress- and subsequent durability analyses. In industrial application advanced FE-models result in high numbers of degrees of freedom, making dynamic analyses time-consuming and expensive. As detailed finite element models are necessary for accurate stress results, the resulting data and connected numerical effort from dynamic stress analysis can be high. For the reduction of that effort, sophisticated methods have been developed to limit numerical calculations and processing of data to only small fractions of the global model. Therefore, detailed knowledge of the position of a component’s highly stressed areas is of great advantage for any present or subsequent analysis steps. In this paper an efficient method for the a priori detection of highly stressed areas of force-excited components is presented, based on modal stress superposition. As the component’s dynamic response and corresponding stress is always a function of its excitation, special attention is paid to the influence of the loading position. Based on the frequency domain solution of the modally decoupled equations of motion, a coefficient for a priori weighted superposition of modal von Mises stress fields is developed and validated on a simply supported cantilever beam structure with variable loading positions. The proposed approach is then applied to a simplified industrial model of a twist beam rear axle.

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MODELING OF THE STRESS-STRAIN STATE OF A TRANSPORT TUNNEL UNDER LOAD AS A MEASURE TO REDUCE OPERATIONAL RISKS TO TRANSPORTATION FACILITIES

EKONOMIKA I UPRAVLENIE: PROBLEMY, RESHENIYA ◽

10.36871/ek.up.p.r.2020.08.03.004 ◽

2020 ◽

Vol 3 (8) ◽

pp. 28-34

Author(s):

N. V. IVANITSKAYA ◽

◽

A. K. BAYBULOV ◽

M. V. SAFRONCHUK ◽

◽

...

Keyword(s):

Strain State ◽

Moving Load ◽

Element Model ◽

Transport Infrastructure ◽

Design Stage ◽

Surface Load ◽

Stress Strain ◽

Stress Strain State ◽

Operational Risks ◽

Von Mises

In many countries economic policy has been paying increasing attention to the modernization and development of transport infrastructure as a measure of macroeconomic stimulation. Tunnels as an important component of transport infrastructure save a lot of logistical costs. It stimulates increasing freight and passenger traffic as well as the risks of the consequences of unforeseen overloads. The objective of the paper is to suggest the way to reduce operational risks of unforeseen moving load by modeling of the stress-strain state of a transport tunnel under growing load for different conditions and geophysical parameters. The article presents the results of a study of the stress-strain state (SSS) of a transport tunnel exposed to a mobile surface load. Numerical experiments carried out in the ANSYS software package made it possible to obtain diagrams showing the distribution of equivalent stresses (von Mises – stresses) according to the finite element model of the tunnel. The research results give grounds to assert that from external factors the stress state of the tunnel is mainly influenced by the distance to the moving load. The results obtained make it possible to predict in advance the parameters of the stress-strain state in the near-contour area of the tunnel and use the results in the subsequent design of underground facilities, as well as to increase their reliability and operational safety. This investigation gives an opportunity not only to reduce operational risks at the design stage, but to choose an optimal balance between investigation costs and benefits of safety usage period prolongation.

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