Archive for February, 2009
Some of the readers of this blog are alumni of the environmental engineering curriculum at the University of Stuttgart. There is a club, called “Kontakt Umweltschutztechnik Stuttgart e.V.”, whose goal is to bring students, teachers, and alumni together in order to exchange ideas and thoughts. Check out the club’s homepage as well as the new XING group!
I’ve spent a fair bit of my time as a grad students trying to model groundwater systems. There have been long discussions on modelling and its philosophy. Today was a PhD defence of such a grad student. Typical thoughts afterwards tend to be “… if we only had more data… ” or “… if we only knew the underlying processes better and could describe them… ” or “… if we only had more computing power available… ” .
I think a key trait of an environmental modeller should be his or her awareness of the quality of the data and the limitations regarding the quality of the predictions of the model. So when I read the headline “Climate Models Trump Financial Models” I was a bit worried. Sure, climate change is a pressing problem, and there is a lot of effort put into improving climate models. However, for me as an environmental engineer it seems that global financial markets should be better understood than global warming. And if it’s only because finance has been around for longer than environmental engineering!
I had never put much thought into how financial models might work, so this article brought up an interesting point for me, even though I’m not quite sure what I think about it:
“Climate models are very complex but you more or less understand the basic physics or chemistry,” said Derman. “[Finance papers] look like physics but a lot of the similarity is syntactic more than semantic.”
For example, stock options are priced with the Black-Scholes model, which says that stock price movement can be seen to move like the random movements of particles suspended in a liquid, i.e. Brownian motion. But stock price models differ from particle models because they describe the aggregate actions of people.
I guess quite a few processes are modelled like Brownian Motion. Why not stock option pricing. This just means though that we don’t know the underlying processes of stock option pricing better, so we could model the pricing in a more deterministic way. Then I thought a bit and it occurred to me that if you asked me, I probably couldn’t explain to you what is going on in the financial world these days. Why are we having this crisis? What are the underlying processes? Then I found this wicked little movie that explains these processes:
Based on this video, this seems to be a fairly straight forward process… But I agree, there is a human factor involved, which admittedly doesn’t make things easier. I wonder what would happen, if you would throw an environmental modeller, a psychologist, and a finance person into a room for a while!
It seems like Weird was on a roll writing about financial models: They also point out, that the length of the finger of a trader is an indication for his degree of success. For me, that seems a little far-fetched! However, there’s again one interesting thought:
But leading up to the crisis — and underlying public acceptance of the mistakes and wrongdoing that produced it — was a widespread belief in the fundamental rationality of free markets and economic behaviors. That assumption may need to be revisited.
Oliver started the blog 22 and a beer. The idea is fairly simple: Go to a restaurant, order whatever that restaurant offers as number 22, take a picture, and write about it. Granted, this has not much to do with water, except maybe that water was used to brew the beer, but it was still fun! Here is my little review!
Sylvia is a deep ocean exploration expert. Her talk is on the importance of the oceans to know everything about our live support system — Earth. She gives a very vivid and powerful presentation trying to motivate us that saving the oceans and marine life is critical. Right now.
She has worked on the team that incorporated the oceans into google earth.
As far as I can see, photos offer three advantages:
- You see through a different set of eyes. When I walk around with my camera up and running, I generally pay more attention to detail and to my surroundings. I turn around more often, and the landscape behind you tends to look differently than in front of you! Without a camera, I tend to miss that part.
- Photography helps your memory. If you have photographs from the past available, they help your brain by remembering how things were, or how things evolved over time. This can be very useful. Do you remember how the chairs in your cafeteria looked like or were arranged 6 months ago? If you have the chance of knowing or storing the information of where the photograph was taken, this is a piece of great additional information. Geotagging.
- Photography is art and as such is beautiful. This is if you are careful by some minimum amount when you create the photography.
Why am I writing about this? Two reasons: primarily I have been having a lot of fun with photography lately, and secondly photography has been proven to be highly useful in a medical case I have been involved with.
Before I went on that trip to Chile, I contemplated for a very long time about which camera to take. I wanted to take a camera, because this is the kind of trip you just don’t do on a regular basis.
I do have some photographic history, which lead to some standards. The history dates back to shooting Lego scenes with my neighbour in the grass of our garden when we were about 8 years old with some obscure Rollei camera. This is where I learned what shutter speed and aperture were. I had no idea about ISO back then. The second flourishing period of my photography past happened during my student-magazine days. I managed to acquire sufficient ads so we had enough money to purchase a Minolta 500si super. That was very thrilling. This was in the late 90s so our school had on the one hand a black and white digital scanner. But one which you had to drag manually over the piece of paper you wanted to scan, and it was only about 10cm wide. It was quite a mess, but very exciting when your picture showed up in Corel 3. On the other hand the school still had a lab, where we developed our b/w film and magnified it on paper. This was so cool. I clearly remember the first roll of film that I took out of its tiny little box. In the dark. And there were only two of us in the lab…
In the end it came down to the question DSLR or point and shoot. More flexibility and picture-quality on a DSLR versus portability on a long backpacking trip. Sony just had released a series of DSLRs on which I could use my old Minolta lenses. I made the decision against heavy weight. As I said, I had some standards, so I still wanted some manual control, so I bought the Panasonic Lumix DMC-FX500. And I have been very happy with it! It has a really great automatic program. It has both aperture and shutter priority. At the beginning I was not sure if the display at the back would be bright enough if it is really light out, but I have been happy with it. The only thing I am not overly happy with is the autofocus. At times it’s a little slow and at very few times it doesn’t focus what I want to focus. I also bought an Amod AGL 3080 GPS tracker, because I wanted to have access to the second advantage from the triplet above. This thing works really nice for its money and for what I wanted it for, for tagging the location of where a photo was taken. Only drawback here is that it goes through batteries quite quickly.
During the trip I had a lot of fun, and I have been using both camera and gps device quite extensively and happily. When I came back, I had about 2000 photographs and a few megabytes worth of gps logs. I was dawn back into daily life quite quickly, but since last weekend I had a new push to work on those pictures. I guess my general feeling was like this: Ok, I have this camera with which I am quite happy, but a DSLR would be a DSLR. I took all these pictures, I had looked through them, they seemed to be ok, but nothing too great, I thought. Then two things happened. I read a blog post, unfortunately I forgot where, saying that essentially every camera is the same, all have a shutter and a lense. So it depends largely on the photographer and what he or she makes out of the situation. On sunday the situation was sunny and snow was on the ground. I switched my camera to black and white mode, yes, back to the roots, baby! Admittedly, this was also inspired by some blog post. And we went on a walk and I took my camera. I guess these days this is called a “photowalk”. And it was a lot of fun!
Afterwards I had built enough desire to look at those pictures from Chile and those gps logs. So I came up with this workflow:
- Take the individual logs, process them, put them in google earth to see where I actually do have a log. This processing I do with a little python script which creates a simple kml file.
- Then I select the pictures which correspond to the location and time of the log file in Lightroom and drag them into HoudahGeo.
- I let HoudahGeo do its magic, check in GoogleEarth if the tagging is correct, and write the locations to the exif file
- I load the metadata back into Lightroom: while still having the pictures I geotagged selected I click under “Metadata” in the menu bar on “Read Metadata from File”.
During the process it is important to pay attention to the times. Before dragging the photos away from Lightroom it might be necessary to “Save Metadata on File” (cmd-S).
This little story made me very happy with photography, again! I have learned a lot about Lightroom and gps on the way! A really great resource for Lightroom has been Scott Kelby’s Lightroom 2 Book! Hopefully I can share some decent Chile pictures or that python script!
Sorry folks for not blogging for a while, but I was having troubles updating to the latest version of the content management system I am using for this blog, Word Press. I just solved the issue, finally, by temporarily de-activating all plugins.
Here is something fun: over at short sharp science they posted this idea of using water. I think it looks awesome and I want to try it! However, I am not sure if ther has been photoshop at use…
- The weather is a federal thing since Feb09, 1870: http://tinyurl.com/bfjltl #
- How people read google results: http://tinyurl.com/abfeld #
- Environmental Engineers and Hydrologists among recession secure jobs! Yay! http://tinyurl.com/ckrlqa #
- Writing style is critical! Everybody knows Watson/Crick. I’ve never heard of Avery et al http://tinyurl.com/62dxnn #
Planetwater.org appears on Andreas Roth’s map that shows the locations of where a given blog is based at.
Great idea for a goole.maps mashup!