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GADeS Summer School on Stability and Bifurcation of Dynamical Systems: Theoretical Aspects and Applications

Dinamica e stabilità

First announcement of
GADeS Summer School on

Stability and Bifurcation of Dynamical Systems:
Theoretical Aspects and Applications

July 3-7, 2017, Savona, Italy

 

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Graphene layers give colourful warning

Graphene layers give colourful warning

Nature

 

543,

 

466

 

(23 March 2017)

 

doi:10.1038/543466a
Published online

 

22 March 2017

Article toSubject terms:

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A simple finding on variable amplitude (Gassner) fatigue SN curves obtained using Miner’s rule for unnotched or notched specimen

We provide a very simple result for a problem which has been often neglected (variable amplitude loading) in academia, but which is of paramount importance in real engineering situations, where fatigue is almost never "constant amplitude".

We found few cases where we could check this extremely simple result, but it worked very well.  We would welcome further verifications.

The paper is in press here.

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5th International Conference on Computational Contact Mechanics

Notice that the deadline for abstract submission has been extended to:  March 17, 2017. 

 

 

 

5-7 July 2017 / Lecce, Italy

 

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Politecnico di Milano creates a large debate in Italy with its decision to teach only in English

Recently, Politecnico di Milano in Italy has attempted to force all teaching at Master level in English.  This has been stopped by some academics who went to different levels of administrative courts, and recently there was a prononciation of the Supreme Court.  The matter is not settled yet, but you can find an account of this with various links here.

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Bigoni's group gets the 4th cover on Proc Roy Soc for Leonardo catapults

The top italian engineer Davide Bigoni gets his 4th cover in Proc. Roy. Soc. A in just 18 months 

See here.

 

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Nature paper about mechanical metamaterials violating Betti's theorem

Maybe because I am proud of Betti's theorem being italian, I am curious about this big emphasys on systems violating it.  They may "open avenues for energy absorption, conversion and harvesting, soft robotics, prosthetics and optomechanics".... ?  I'd be curious to hear some comments.   Anyway, the last author Andrea Alu is anyway italian like Betti.

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3D Printing Grand Challenge

Abstract Submission Extended to March 1st 2017

More information

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10th European Solid Mechanics Conference – ESMC 2018

 

Dear Colleague,

 

We are pleased to announce the 10th European Solid Mechanics Conference – ESMC 2018, which will be held in Bologna (Italy) during July 2-6, 2018
The Conference is organized by the University of Trento and the University of Bologna.

 

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moving singularities (crack analogues) in fretting fatigue

    The stress concentration induced by fretting fatigue was studied with a simple "Crack Analogue" model (CA) by the MIT group of Suresh in the late 1990's, which was then "improved" by the present author to take into account simply both contact loads and bulk stresses loads, and even the case of finite stress concentration in the so-called "Crack Like Notch Analogue" (CLNA) model.

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top italian scientists

I just read in the news about 3 italians who won the prestigeous CASE award.  They are relatively young, and I see do not have a very high H-index.  I think there was a discussion in Imechanica years ago about the fact that H-index is still an experimental data point where we don't know how else to judge a scientist.

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On Pastewka and Robbins' Criterion for Macroscopic Adhesion of Rough Surfaces

On Pastewka and Robbins' Criterion for Macroscopic Adhesion of Rough Surfaces

M. Ciavarella

[+] Author and Article Information

J. Tribol 139(3), 031404 (Nov 30, 2016) (5 pages)

Paper No: TRIB-16-1057; doi: 10.1115/1.4034530

History: Received February 15, 2016; Revised July 18, 2016

ARTICLE

REFERENCES

Abstract

Abstract | Introduction | A Simple Asperity Model | Pull-Off | Discussion | Conclusion | References

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Lorentz Workshop "Micro/Nano Models for Tribology," Leiden, the Netherlands, 30/1-3/2/2017

We have organized a Lorentz Workshop with 60 selected partecipants leading scientists in tribology and contact mechanics mainly from Europe.

Attached a program.   Or see the web site

Micro/Nanoscale Models for Tribology (μ/n-Tribo-Models) 

Vladislav Yastrebov (co-organizer)

Lucia Nicola (co-organizer)

Annalisa Fasolino (co-organizer)

Michele Ciavarella (co-organizer)

Julien Scheibert (co-organizer)

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remove an entry

dear imechanica 

   I wanted to remove one entry but I don't seem to be able to remove entries any longer like it was possible before --- how can I do that?

 

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rate-state dependent friction in ANSYS

Dear collegues

a quick question:- I am playing with continuum models of Contact (Hertz, Westergaard and so on) and friction laws. However, I prefer for my students to use ANSYS FEM code. In Ansys there is standard Coulomb, rate-dependence but not rate-state (unless one codes some user subroutines). See

https://www.sharcnet.ca/Software/Fluent14/help/ans_ctec/Hlp_ctec_realkey...

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a JKR theory of adhesion for anisotropic solids

Jim Barber and I just got accepted this paper in JMPS, and it is also already available on Arxiv.  We found a remarkably simple closed form solution for adhesion on orthotropic materials in the planes of symmetry.  This shows adhesion can increase significantly due to anisotropy, namely the JKR solution continues to hold in the sense of mean elastic modulus, but the prefactor can grow without limit. We expect applications in crystals indentation, but also in locomotion in biological world.

 

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How safe are metal-on-metal hip implants? and are ceramic-on-ceramic safer? Or we will discover soon they are not?

Would you believe this story?

To me, that metal - on - metal had large friction, especially with the newest designs, it was clear from the old Sir Charnley studies in Leeds in 1950s published in his gold book. 

Anyway, when I looked at ceramic on ceramic joints, I also found evidence of increased friction.  Maybe ceramic debris is less toxic?

Please comment.  What can we do outside USA to improve the situation?

Michele Ciavarella 

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