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Ying Li's picture

How to prevent the trash ADs at iMechanica?

Recently, more and more trash ADs appear at imechanica. The users like "ORDER CIALIS ONLINE - US DRUGSTORE FDA" have added the ADs at the comments. Is there any good method for us to prevent such behavior at imechanica? As one of the moderator, may I have the right to directly give such users name to system operator to prevent these trash ADs?

Any comments are welcome.

Ying Li

Zhigang Suo's picture

Mechanics thrives whenever it participates in advancing a new technology

This morning I was looking at the book Mechatronic Reliability by Wei Yang.  The forword I wrote for the book brought back memories of days he and I spent in Santa Barbara and Princeton.  The text of the forword follows.

Finance and Mechanics


Recent events about the financial crisis and generally spread turmoils on Economics and Financial Environments  lead me to these conclusions.

Critical Speed:  informations, a key issue on finance, reached a critical speed. Maybe this is the "first" critical speed of the system. Speed of informations has reached the same order of magnitude of people's judgement (executives and investors more than others) so there's a sort of over-reaction about actual events.

Teng Li's picture

iMechanica: 9000 registered users, 30,000,000+ web hits

The number of registered users of iMechanica reached 9000 on 13 October 2008, after two years and one month since the website launch. The total number of posts is 4036, the total number of comments is 8888, and the total web hits is estimated to be more than 30,000,000.

Hosted at Harvard School of Engineering and Applied Science and maintained by a growing number of volunteers, iMechanica aims

The post LHC universe?

Most of you have heard about the commissioning of the Large Hadron Colider (LHC) by CERN and then the explosion of Helium followed by a postponement of operation until spring next year.  One of the worries some people had was that a mini black hole would be created by the collsions.  Also, the anthropic principle in one of its forms suggests that every possible universe exists but we see only our universe because it's the one in which intelligent observers exist.

How to ask a question on iMechanica

I've mostly had quite helpful responses from iMechanica participants whenever I've asked questions on this forum.  However, I've noticed that questions from several posters have gone unanswered.  I feel that there are two main reasons for that lack of response:

1) The questioner has not provided an adequate details by which they can be identified.  I generally don't like responding to a question posed by someone called xyz1983. 

Mike Ciavarella's picture

China: The prizes and pitfalls of progress

Remember when I spoke of the Easterlin paradox (a key concept in happiness economics postulated by Richard Easterlin in the 1974 paper "Does Economic Growth Improve the Human Lot? Some Empirical Evidence."[1]
It finds that, contrary to expectation, happiness at a national level

Mike Ciavarella's picture

Mars and Venus - How Europeans and Americans View and Use Science - ESOF July20th -Part 1: The Eu Perspective -

From ESOF, an interesting presentation, attached. 

Mars and Venus
How Europeans and Americans
View and Use Science<
Part 1: The European Perspective

Dr Roland Schenkel, Director General, European Commission, Joint Research Centre (JRC)

 Some quotes

A new theory of stress?

I was browsing the discussion page for Stress in Wikipedia when I came upon this interesting comment:


Refutation of Cauchy stress

The theory of stress based on Euler & Cauchy is now refuted. The profound incompatibility of this theory with the rest of physics, especially the theory of potentials and the theory of thermodynamics, has been documented in

Mike Ciavarella's picture

Schwarzenegger, Obama, and Energy-related position at the White House

July 13, 2008, 7:31 pm

Schwarzenegger Says He Would Accept Obama Appointment

Melanie Trottman reports on the presidential race.

Guests on the Sunday newsmaker shows, including California Gov. Arnold Schwarzenegger and John McCain adviser Carly Fiorina, spotlighted energy and the economy and paid tribute to former White House press secretary Tony Snow.

ericmock's picture

So, What's It Gonna Be?

Teacher, Scientist, or Engineer

From thinking about the 'I'd Love to Change the World' discussion, I have concluded that my dilemma stems from the (basically) three career paths from which I can choose.

A teacher that can have a great deal of influence on a select number of other individuals' lives and can take great pride in helping others achieve their potential, and possibly make great contributions to society.

A scientist that can continue to explore the unexplained and hopefully discover something that could contribute to society.

Mike Ciavarella's picture

How Many Friends Is Too Many? 5000? Then imechanica is too many!


How Many Friends Is Too Many?

One MySpace exec has even surprised himself by friending a potato. This particular russet has 2,965 friends.

May 26, 2008 Issue


ericmock's picture

Artificially High Read Counts


There has been some discussion about the low ratio of replies to reads on iMechanica.  While it's nice to think that a lot of people are reading our posts, I wonder how many of those 'reads' are really bots indexing the page.  For example, I posted a blog entry last night around 11:00 and nine hours later it says it has been read 45 times.  A couple of those can be attributed to me but I'm sure 40 real people have not read the post.  Add to this the fact that the post is already showing up in Google.

ericmock's picture

I'd Love to Change the World...

...But I Don't Know What to Do...

 ...So I Leave It Up to You

 by Ten Years After ( or on iTunes)


Viscoelastic prarameters setting in ABAQUs

i'm try to do a dynamic analysis by abaqus and i faced some problems.any help is appreciated.

The structure is a 3 layers plates,a viscoelastic material sandwich between 2 steels.i modeled the 2 steel as sheel 'S8R"and the rubber as contiuum  "c3d20r",rubber is not thin. Now i don't know how to set the parameters requried by the Code.I hove some parameters abuout the viscoelastic material.,includeing shear storage modulus G(f)=exp(-2.69292)*f^(0.6937),and loss factor of the material L(f)=exp(0.60503)*f^(-0.08807), Possion ratio=0.49, where f is frequency in Hz.

Ettore Barbieri's picture

The Future of Meshless Methods

I joined imechanica almost a year ago and I've been frequently following its interesting discussions, even the most animated ones. I think that a place like this is ideal to foster the exchange of ideas in the scientific community;

Moreover it is fantastic as a simple student like me can interact and easily ask questions to the most important researcher in the field of mechanics.

Problems of researchers in third world and how IMECHANICA can help them (it is not money).

many researchers in industrial countries think the only problem of third world researchers is money but it is not true. I worked as a researcher for four years in one of this third world countries.

Computational and Theoretical research dont need much money as like as lab dependent research. because freeware and opensource became popular and (the copyright laws are not strict in these countries unfortunately).many experimental works also can be done with available facilities in these universities.

Earthquake in West China and lessons for us!

In Singapore, I have seen students who lost their relatives in last earthquake. I am very sorry about this, but I think there should be lessons for us in such disasters.  Is'nt any cheap and easy way to reinforce building in the face of earthquakes? I hope such disasters make researchers concentrate on such important topics.

A lack of heroes, a lack of open culture

One of the things that I've thought about often in relation to mechanics is:

Roberto Ballarini's picture

National priorities

The research funding environment we are all experiencing is extremely frustrating, and has the potential for long-term damage to academics and the nation. You may be interested in reading the letter to the Wall Street Journal by two Nobel Prize winners, David Baltimore and Ahmed Zewail.

Ravi-Chandar's picture

Grand Challenges For Engineering

The US National Academy of Engineering has published a list of Grand Challenges for Engineering. Ths US National Committee on Theoretical and Applied Mechanics is interested in developing a discussion on the implications of these Grand Challenges to the Mechanics community.


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