Zhigang Suo's blog

When I traveled in China in June, I was once again irritated by the Internet.  It was often slow and broken.  Many important services are inaccessible, blocked by someone.  Why would someone do that?

But I found my Chinese colleagues extremely well interconnected.  Everyone has a cell phone.  They actually use their cell phones!  

I'll be teaching an undergraduate course on engineering thermodynamics.  We will use the textbook by Cengel and Boles.  I will supplement the textbook using my own notes on thermodynamics.

The initial issues of Extreme Mechanics Letters are freely accessible.  We look forward to receiving your submissions.  Your contribution will help to build this home of mechanicians.

Editors-in-Chief

• Jimmy Hsia, Carnegie Mellon University

与中国一起走向世界，与世界一起走向未来

锁志刚

西安交通大学毕业典礼，2015.6.27

尊敬的张迈曾书记，尊敬的王树国校长，

各位嘉宾，各位老师，各位同学，各位家长，

大家上午好！

感谢学校让我作为校友在毕业典礼上致辞。年轻的同学们，我想和你们谈一个大家都关心的话题：机会。

A state of stress in a body.  Components of stress.  Subject to a load, a body develops internal forces.  The distribution of the internal forces in the body is usually inhomogeneous. For example, when a rod is bent, part of the rod is in tension, and the other part of the rod is in compression.

If the internal forces are uniformly distributed in the body, the body is said to be in a homogeneous state of stress.  For brevity, we often say a state of stress, or just stress.

This question was raised repeatedly when the journal Extreme Mechanics Letters was getting ready to launch.  The editorial board did put together the aim and scope.  But the journal has its own life.  Once launched, it has been shaped by the community.

The attached notes are written for a course on plasticity.  When I update the notes, I will post a link on my twitter account:  https://twitter.com/zhigangsuo.  

Rheology is the science of deformation.  This science poses a question for every material:  Given a history of stress, how do we predict the history of strain, or the other way around?

The attached notes are written for a course on plasticity.  When I update the notes, I will post a link on my twitter account:  https://twitter.com/zhigangsuo.

The attached notes are written for a course on plasticity.  When I update the notes, I will post a link on my twitter account:  https://twitter.com/zhigangsuo.

I have just updated my notes on nonlinear viscosity.  The notes are written for a course on plasticity.  When I update the notes, I will post a link on my twitter account:  https://twitter.com/zhigangsuo.

The attached notes are written for a course on plasticity.  When I update the posts, I will write a note on my twitter account:  https://twitter.com/zhigangsuo.  

In a pure liquid, molecules touch one another but change neighbors frequently.  External forces cause the liquid to change shape by viscous flow.  Thermal agitation causes  molecules to undergo self-diffusion.  The two phenomena--viscous flow and self-diffusion--often result from a single rate-limiting process:  molecules change neighbors.  This simple picture is amply confirmed by the Stokes-Einstein relation, which links the viscosity and self-diffusivity for many liquids over wide ranges of temperature.

The attached notes are written for a course on plasticity.  I will update new posts on my twitter account:  https://twitter.com/zhigangsuo.  

The attached notes are written for a course on plasticity.  I will update new posts on my twitter account:  https://twitter.com/zhigangsuo.  Rheology is the science of deformation. This science poses a question for every material: given a history of stress, how do we find the history of strain?

I am teaching this course this semester.  I'll post notes as I write them.  Links to the notes are listed in this post.  I will also notify updates on twitter:  https://twitter.com/zhigangsuo

I wrote these notes as a background for teaching elasticity and plasticity.  Even in this most basic formulation, the dilation of the fluid is viscoelastic.

A previous post, Getting Ready for Extreme Mechanics Letters, contained the following paragraph:

“We seek papers from researchers in all disciplines. Mechanics appeals to talents of all kinds. Good mechanics has long been created by people from many fields, by Galileo, Newton, Maxwell and Faraday, as well as by Watt, Darwin, Wright brothers and Whitesides. People make discoveries in mechanics often when doing something else (e.g., in seeking evidence for the existence of God, in building cathedrals, in flying airplanes, in laying transatlantic telegraph cables, in fabricating microprocessors, in watching cells move, in fracking for gas, in inventing optical tweezers, in creating soft lithography, in developing wearable or implantable electronics). Mechanics discovered in one field invariably finds applications in other fields.”

Here I would like to give several examples of papers published in recent decade or so. I will link each paper to its citations on Google Scholar, so that you can have an overview of the influence of the paper on other researchers.

Starting a new journal is risky.  Starting a new journal in mechanics is particularly risky.  The responses to the two recent posts are encouraging, however.

• Getting ready for Extreme Mechanics Letters

• What can iMechanica do for Extreme Mechanics Letters

We are launching a new journal, Extreme Mechanics Letters. EML will publish letter-sized papers. We aim to achieve rapid communication. Our goal is to have the accepted papers published within 6-8 weeks upon submission. We aim to build a home at the frontier of engineering, medicine, science and entertainment, where advances are rapid and mechanics matters. We seek papers from researchers in all disciplines.

We will start to review submissions on 1 October 2014, and publish first papers by 1 December 2014. The beginning issues will be freely accessible online, and printed copies will be distributed at conferences.

We love to publish your extremely new ideas on extremely useful and extremely interesting mechanics. Please submit your papers soon.

The nervous system has long been an inspiration for the engineer.  Here is an example in a popular textbook on neuroscience.  When a person steps on a nail, the sensor in his foot sends a signal to his brain, the brain sends a signal to his muscle, and he lifts his foot.  The example illustrates the sensor, actuator and processor in the nervous system.

Here is the call for proposals .   The due date is 1 May 2014.

Ju Li, Zhiwei Shan and Evan Ma have edited the February 2014 issue of the MRS Bulletin devoted to the effects of elastic strains on solid-state devices.

The Harvard School of Engineering and Applied Sciences seeks applicants for the position of Senior Lecturer in Applied Mathematics, with an expected start date of July 1, 2014. This position will be for five years and may be renewed.  Deadlin for application is 15 March 2014.  See further information.  See also a position for Applied Math Fellows.