Category: Geek stuff

If it involves physics, math, computer science, electronics or has general geek cachet, this is the place for it.

Microsoft’s imitation Google

Microsoft’s new Bing search engine is a bit bewildering. To call it an homage to Google is an understatement: complete with ‘Web,’ ‘Images,’ ‘News,’ ‘Maps,’ etc across the top bar. While the bird’s eye feature in Bing Maps is a bit neat (it seems like it might be based on HDR images), one cannot easily shake the feeling that Microsoft decided to respond to Google’s approach by outright copying it. The only oddity is that, because I have my Windows language set to British English (so it knows how to spell ‘colour’), this makes Bing think I am in the UK, and the site offers me no option for showing Canadian results or news. Not very clever, given the ease with which an IP address can be turned into a location.

Has anybody discovered any Bing feature that is either quite different from or better than a Google offering? Hotmail certainly cannot begin to touch the searchable glory that is GMail.

Hashing with Wolfram Alpha

Separately, I have discussed both the Wolfram Alpha computational knowledge engine and the practice of hashing information. The fact that WA allows anyone to do so easily has relevance for things like making bets online, in situations where players want to conceal their guesses until everyone else has put theirs up.

Here is an example. Say you want to place bets on who will win the next Republican presidential primary. You don’t want those who post later to have the advantage of knowing what others have already posted, so you do the following:

  1. Choose a hash algorithm (MD5 should be fine, but SHA is more secure)
  2. Have each participant put their guess into WA. Say I think it will be Sarah Palin. I would enter: “SHA “I think the primary winner will be Sarah Palin, though I fear what she will do with the country” into Wolfram Alpha, and it would spit out something like “f7ca 4adf 11c7 5b56 f355 1635 5b50 2eca 5950 5349”
  3. Note that the supplementary text, in addition to the name, is vital. Otherwise, it would be trivially easy for the other players to check the hashes for likely guesses and learn what people have chosen. Incorporating a salt into the hashing algorithm would be ideal, but WA doesn’t seem to have that capability.
  4. Have each participant post the hash of their response, saving the exact text somewhere secure to them.
  5. When the outcome is known, those who guessed correctly can confirm that fact, by providing text that hashes into their original post.

A somewhat roundabout and nerdy solution to a relatively unimportant problem, perhaps, but it illustrates some of the ways hashes can be used to prove what you said earlier, without having the content of your earlier message immediately accessible – a general ability with many applications.

One more fact about salts: they are the most straightforward way to foil attacks using rainbow tables.

UBC’s footprint reduction contest

The University of British Columbia is holding a contest where participants will set out plans on how to make the Point Grey campus “net positive” in terms of energy and water, as well as reduce greenhouse gas output. The grand prize is $5,000, second prize is $3,000, and third prize is $1,000. The contest is open to UBC community members (ie: Student, Staff, Faculty, Researcher, Resident or Alumni).

Net positive water output seems like something that could be achieved fairly easily. You would capture and purify rainwater, use it to cover all on-campus activities, and export a bit into the water system beyond. It would require infrastructure spending, but it seems clear that it could be done.

Net energy output (in a zero carbon way) might be trickier, though I presume it isn’t necessary for the campus to be exporting power to the grid all the time. As long as net exports are positive, it seems fair to call the campus “net positive” on energy. Wind and solar are the obvious renewable options, though UBC isn’t really an ideal location for either. My guess is that the best option would be to install wind and solar capacity, while retrofitting buildings to make them much more energy efficient.

Contest guidelines are online. (PDF)

David MacKay’s sustainable energy calculations

For all the readers on this site interesting in climate change, policy, and technology, David MacKay’s book Sustainable Energy – without the hot air is a text that could be very profitably incorporated into our discussions. It seeks to evaluate whether (and how) society could operate without fossil fuels. It does so systematically, with all work shown, allowing you to question the methods and perform your own calculations for different circumstances. Another nice feature is that it is available online for free, though you may find it worthwhile to buy a professionally printed and bound copy.

The book is all about what is physically possible, rather than what is economical. As such, it sets a kind of base standard for sustainability. It evaluates whether something can be done at any cost, a pre-requisite to it being possible at a reasonable one.

To begin with, here is the methodology (p. 22 -28). It explains the exercise being undertaken and explains the key units to be used. The main unit of power selected is the somewhat unusual kilowatt-hour per day (kWh/d) per person (/p). While watts are more conventional, this unit does have some virtues in making things easily comparable and comprehensible. After all, if a kilowatt-hour (kWh) of electricity costs me about five cents, it is easy to start thinking about the economics of an activity that requires 30 or 40 kWh/d.

Here are a few chapters that touch directly on debates that have occurred (sometimes raged) on this site:

All the other chapters are relevant, as well, but these seem especially likely to inject some new information and thinking into long-running discussions.

The United Kingdom seems to be spoiled with people who are willing to perform comprehensive analyses of how their whole societal energy system could be rendered comparable with a stable climate (George Monbiot’s book is another example). It almost seems worth going through this entire text and re-performing the calculations with Canadian figures as inputs.

Somewhat short of that, would anyone be interested in going through the book chapter by chapter?

Bicycle physics

For those with an interest in both cycling and physics, the Wikipedia article “Bicycle and motorcycle dynamics” is well worth reading. It is interesting to note that lateral movements of bicycles (basically, those involving turning) are so mathematically complex that they require “two coupled, second-order differential equations… to capture the principle motions” and that these equations cannot produce exact solutions.

That contrasts in an interesting way with the experience of making turns at speed on a bicycle, and the appreciation one gains for the relationship between body movements, bicycle movements, and the condition of the ground.

Energy efficiency and Ottawa’s Dominion Observatory

Dominion Observatory - NRCan Office of Energy Efficiency

Wandering around the experimental farm, I ran across one of my new favourite buildings in Ottawa. Natural Resources Canada has an Office of Energy Efficiency housed in an old observatory that would look at home in Oxford, Myst, or a neo-Victorian steampunk fantasy. It has great brickwork, an attractive green copper dome, interesting detailing, and a nice setting uphill from Dow’s Lake. The building is called the Dominion Observatory, and served in that capacity from 1905 to 1974, with a 15″ refracting telescope installed in the main dome.

I will need to find some pretense for getting invited in. I will also need to go back at a time when the lighting is more favourable, and when I have a tripod with me.

Photos of Ontario and Quebec birds

Here is a list of the birds I have photographed so far as part of my open-ended project. The links go back to the posts in which the photos originally appeared. Eventually, I might sub-divide this list according to type or location.

Presently unidentified birds: none.

Colour-based Google image searches

Google Image Search now lets you search for images that are predominantly similar to twelve different colours. For instance, the set of all photos from my site they have indexed can be restricted to just those with red highlights or those dominated by blue.

All told, Google currently includes 204 images from my site in their index. Here is the colour breakdown:

  • Red: 10
  • Teal: 7
  • White: 11
  • Orange: 17
  • Blue: 25 (lots of the sky)
  • Grey: 41 (many of them in black and white)
  • Yellow: 2
  • Purple: 2
  • Black: 47
  • Green: 8
  • Pink: 0
  • Brown: 45

You can also search for various image types: news content, faces, clip art, line drawings, and photo content.

As ever, Google Image Search is a somewhat perplexing creation. It’s not clear why it selects the photos it does or how it ranks them. I look forward to further improvements in the service.

Climate sensitivity roulette

Big Bird in a cage

As discussed several times previously, two of the key uncertainties relating to climate change is (a) how much temperature would increase in response to any particular change in the atmospheric concentration of greenhouse gasses and (b) what humanity will actually emit between now and the achievement of global carbon neutrality. One way to express those uncertainties colourfully is with the Roulette wheels the MIT Joint Program on the Science and Policy of Global Change has created.

The wheels are based on results from the MIT Integrated Global Systems Model and have shaded areas proportional in size to different possible levels of temperature increase. The projections were recently updated, and the new ones contain significantly higher estimates of the risks of high levels of warming:

The new projections, published this month in the American Meteorological Society’s Journal of Climate, indicate a median probability of surface warming of 5.2 degrees Celsius by 2100, with a 90% probability range of 3.5 to 7.4 degrees. This can be compared to a median projected increase in the 2003 study of just 2.4 degrees. The difference is caused by several factors rather than any single big change. Among these are improved economic modeling and newer economic data showing less chance of low emissions than had been projected in the earlier scenarios. Other changes include accounting for the past masking of underlying warming by the cooling induced by 20th century volcanoes, and for emissions of soot, which can add to the warming effect. In addition, measurements of deep ocean temperature rises, which enable estimates of how fast heat and carbon dioxide are removed from the atmosphere and transferred to the ocean depths, imply lower transfer rates than previously estimated.

Full article

The ‘policy’ wheel assumes aggressive mitigation action, while the ‘no policy’ wheel assumes a business-as-usual course. It is notable that the chances of keeping warming below 2°C are infinitesimal, on that wheel. Even with aggressive action, our changes of keeping below 2°C of increase are looking increasingly distant, with effects that may be severe for both human and natural systems.

In addition to being a good visual image, I like the conceptual linkage between climate change and gambling. We are certainly taking a chance, whatever we do, but science can help us to assess the odds we face and make choices that reduce the risks of unacceptable outcomes.