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Jan Jensen
Works at University of Copenhagen
Attended Iowa State University
Lives in Copenhagen
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The May issue of  Computational Chemistry Highlights  is out. CCH is an  overlay journal  that identifies the most important papers in computational and theoretical chemistry published in the last 1-2 years. CCH is not affiliated with any publisher: it is a...﻿
The May issue of Computational Chemistry Highlights is out. CCH is an overlay journal that identifies the most important papers in computational and theoretical chemistry published in the last 1-2 years. CCH is not affiliated with any publisher: it is a free resource run by scientists for ...
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PBL in a physics class

Should you implement problem-based learning when teaching physics? My first impression is yes it should work. Here's a short & simplified case description of my recent experience of PBL that we did during a pedagogy course in University of Helsinki.

There had been a car accident in a road crossing. The police wanted to know if one of the drivers was guilty. We knew about the drivers' conditions after the accident. We knew the speed limits etc. and data like the weights of the cars, the point where the cars had hit each other, the final locations of the vehicles and marks on the road. Plus that it had been a sunny day (but would that be important?). The description seemed understandable. So the 1st PBL step was cleared.

We ran into confusion. What's there to find out? Seemed there's still not enough information, the case is not well described. Should the police rush into the hospital to interview the drivers or what? We needed to find out what happened and decided more information is needed. This was our 2nd PBL step, defining the problem.

Brainstorming followed and a lot of post-it notes on all things related to the case were produced - the 3rd PBL step.

After reorganizing it started to make sense, there's physics issues and other issues that one could look into. As it was physics-related we focused on the idea that we need a clear description of the physical situations, quantities and factors affecting the moving objects. This combined with the laws of physics should be enough to solve the initial velocities of the cars, the question who is guilty.

Thus the 4th PBL step was reached: our working hypothesis was that if we figure out clearly the data, the geometry and the relevant equations for the situation we could solve the problem. As the learning objective (5th PBL step), we decided to build the full model for the accident from the physics point of view.

The rest turned out to be a nice and useful refreshing of memory about conservation of momentum in the collision, kinetic energy, accelerating and decelerating movement, first as individual learning (6th PBL step). One of us put the things on a spreadsheet for easy simulation and the model was clear after our group meeting and checking the details. We continued more to learn and refresh the topics individually. The final collecting and presenting of the results followed (7th PBL step). The spreadsheet was useful to check how the initial values influence the end result (that is, under which conditions the drivers were guilty).

It was a great hands-on learning experience of what #PBL   can be in #physics education, and it was clearly learning together in a group with people from different backgrounds. Thanks for interest on this . There's probably many ways how this case could be extended and designed for more advanced courses. However, PBL doesn't make the life of the teacher any easier than in other courses - more on this later.

#pedagogy

What is problem-based learning? My post with a couple of links: http://sco.lt/5k2fOT  ﻿
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Thanks for sharing. I added more description in the comments section of the original post.﻿

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Energy Minimization: Finding and Connecting Stationary Points
Let’s start by considering a simple example with one coordinate (for example a distance), $R$, and where the energy is given by $$E= \frac{1}{2}(R-R_e)^2$$ The corresponding potential energy surface, known as a quadratic PES , is shown in Figure 1. Figure ...﻿
Here $R_e$ is the value of $R$ at which the energy is lowest (this is known as the equilibrium geometry) and this is what we'd like to find. We start by taking a guess at $R$, $R_g$. We already know how to check whether this is an energy minimum: we need to evaluate the gradient, which is ...
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Exploring the Accuracy Limits of Local Pair Natural Orbital Coupled-Cluster Theory
Dimitrios G. Liakos, Manuel Sparta, Manoj K. Kesharwani, Jan M. L. Martin, and Frank Neese  J. Chem. Theory Comput.  2015, 11, 1525−1539 Contributed by  +Jan Jensen Reprinted with permission from  J. Chem. Theory Comput.  2015, 11, 1525-1539. Copyright (201...﻿
Two years ago Neese and co-workers published the first CCSD(T) calculation on a protein (crambin), which, according to this latest paper remains "the largest coupled cluster calculations reported to date". The calculations were made possible through the domain based local pair natural orbital ...
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On the other hand I have a bit of a tendency to think in too complex terms. And I kind of liked it that in your other quizzes the obvious answer often isn't the correct one, if you start thinking a bit. So I did the same here and now it failed. : )

I wouldn't have made this mistake if the question was about the amount of hydrogen bonds instead of the amount of shown compounds.﻿
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When working with molecular dynamics in #ATK, you can also use it for generating amorphous structures. Have a look at this tutorial to learn how. #moleculardynamics http://ow.ly/NqAil﻿
Amorphous solid materials become more and more important for a broad spectrum of technologies. In contrast to crystal structures, which are usually we...
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This is a very useful tutorial .﻿

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10 facts about learning that are scientifically proven and interesting for teachers﻿
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GAMESS on the Raspberry PI﻿
Raspberry Pi [RPi], Model B rev 2, the 40 \$ computer, is now available since almost two years. Many educational applications have been described. In November 2013, even Wolfram Mathematica 9 has been donated to RPi as a free programming environment and is included in the newest Raspbian download ...
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In his circles
150 people
Have him in circles
874 people
Work
Employment
• University of Copenhagen
Professor of Bio-Computational Chemistry, present
• University of Iowa
1997 - 2006
Places
Currently
Copenhagen
Story
Introduction
I am a computational chemist working at the University of Copenhagen.  I work on protein design, quantum chemistry methods, and visualization
Education
• Iowa State University
Basic Information
Gender
Male