Blood Clot Mechanics at the Molecular Level
Cross-posted to Biocurious a blog about biology through the eyes of physicists.
Blog posts
Solution of system of Differential equations
Dear Wei and Mogadalai,
As mentioned earlier I am trying to solve for a vector {x} from
{x'}=[A(t)]{x}
where [A(t)] is known matrix of size (2X2) at the max 4x4, elements and are functions of "t".
{x} is a vector (nX1) function of 't'
{x'} is derivative of {x} with respect to 't'.
PhD and Postdoctoral Scholarships in Theoretical Modelling and Numerical Simulation of Snow Avalanche, Austria
University of Natural Resources and Applied Life Sciences, Vienna, Austria
A three-year fully funded PhD and a two-year postdoctoral scholarships are available immediately within a research project financed by the Austrian Science Foundation (FWF).
The project deals with the theoretical modelling and numerical simulation of snow avalanches. Some emphasis is given to the interaction between snow avalanches and protection structures. The research of the applicants will include the further development of the theoretical model and the numerical analysis aimed at optimizing obstruction geometry and arrangement of snow protection. We expect candidates from one of the following research fields: physics, mathematics, engineering science, particularly fluid mechanics. The candidates should have a strong theoretical or numerical background, and proficiency in English.
Stress analysis of adhesive layer in a sandwich specimen
I just came across the lecture notes from Professor Nix on Mechanical Properties of Thin Films. It is very educative and helpful. I wonder if anyone could recommend some analytical derivation on the stress of the adhesive layer between two similar/dissimilar adherends (sandwiched specimen) under mechanical or thermal loading.
Many thanks ...
Phase field simulations of polarization switching-induced toughening in ferroelectric ceramics
Polarization switching-induced shielding or anti-shielding of an electrically permeable crack in a mono-domain ferroelectric material with the original polarization direction perpendicular to the crack is simulated by a phase field model based on the time-dependent Ginzburg-Landau equation. The domain wall energy and the long-range mechanical and electrical interactions between polarizations are taken into account. The phase field simulations exhibit a wing-shape- switched zone backwards the crack tip.
"Wrinkled hard skins on polymers created by Focused Ion Beam", PNAS , January 2007
A stiff skin forms on surface areas of a flat polydimethylsiloxane (PDMS) upon exposure to focused ion beam (FIB) leading to ordered surface wrinkles. By controlling the FIB fluence and area of exposure of the PDMS, one can create a variety of patterns in the wavelengths in the micrometer to submicrometer range, from simple one-dimensional wrinkles to peculiar and complex hierarchical nested wrinkles. Examination of the chemical composition of the exposed PDMS reveals that the stiff skin resembles amorphous silica. Moreover, upon formation, the stiff skin tends to expand in the direction perpendicular to the direction of ion beam irradiation. The consequent mismatch strain between the stiff skin and the PDMS substrate buckles the skin, forming the wrinkle patterns. The induced strains in the stiff skin are estimated by measuring the surface length in the buckled state. Estimates of the thickness and stiffness of the stiffened surface layer are estimated by using the theory for buckled films on compliant substrates. The method provides an effective and inexpensive technique to create wrinkled hard skin patterns on surfaces of polymers for various applications. Click here for access to the full article. See also the press release: Applied scientists create wrinkled 'skin' on polymers
Summer Internship at Sandia National Labs, Livermore, CA
Sandia National Laboratories, California has established the Engineering Sciences Summer Institute (ESSI) program, in which applied mechanics, structural analysis and mechanical engineering graduate students are invited to spend a summer at SNL/CA performing research that would jointly benefit the students and Sandia. The program is nine years old and a description of the program is attached. Because of the funding base for this program, we can only consider students having U.S.
2007 ASME Congress, 12-15 November, Seattle, Washington
Deadline for submitting an abstract: 5 March 2007.
Responding to the wishes of members, the ASME Congress will change to a new format, starting this year. Sessions will not be allocated to Divisions, but will be allocated to symposiums after abstracts are reviewed. Thus, your action item is to submit an abstract to a symposium. Here are terms as used in the 2007 Congress:
Session. Technical sessions will be scheduled for four days, Monday-Thursday. Each session will last 90 minutes, and consists of 4-6 talks. There will be 23 parallell sessions at a given time, 5 time slots for sessions per day, and a total of 23x5x4 = 460 sessions for the entire congress.
Final Exam: ES 240 Solid Mechanics
Notes for students who are preparing for the final.
- Time: 9:15 am, Thursday, 18 January 2006. Place: Sever Hall 206. No notes or books. Calculators are allowed.
- There will be 3 hours and 5 problems.
- Exam problems will mostly draw upon homework and parts of the lecture notes covered in class. The exam intends to test your understanding of the material covered in the course, not your creativity.
- For the last two topics covered in class, finite deformation and strings and elastica, there was no homework, but some exercises are scattered in the notes. They may appear in the final.
- For equations, you will need to memorize the most basic ones, such as equilibrium equations, Hooke's law, and strain-displacement relations. But for anything that you cannot remember, you should be able to derive.
Grade distribution