Hubble’s new lease on life

Abstract colour and shape

Good news for anyone interested in the nature and content of our universe: NASA has reversed course and decided to repair the Hubble Space telescope. For many with an interest in astronomy, the idea that this fine instrument would be allowed to fall out of orbit seemed quite mad.

The refit, which should take place in 2008, should extend the life of the telescope until at least 2013. The primary objective will be to replace failing batteries and gyroscopes, though new instruments will also be installed.

The Hubble instrument has already generated some of the most important data in the history of astronomy and cosmology, including totally new information on very distant objects generated through the use of gravitational lenses: where the light-bending properties of galaxies are used on a massive scale to resolve extremely distant objects. Since the light being observed has been traveling for so long, such views are also a glimpse into a much earlier time in the development of the universe.

In contrast to manned space flight – which is inspirational but not always very scientifically useful – it is this kind of experimentation that we should be focusing our research dollars and efforts upon.

Let my packets go!

Oxford Social Sciences Library

Why is wireless networking so dodgy right now? I am not talking about typing 400 character messages into your phone with your thumbs, but about accessing something really useful with a device not physically connected to a computer network.

Not to sound like Margaret Thatcher, but a big part of the answer is government regulation. Back in the day when analog cellular phones were a dream, there was a belief that radio frequencies had to be allocated, for eternity, to a particular group for a specific use. The advent of cool networking technologies like CDMA has demonstrated that this is not only wrong, but incredibly inefficient.

If we abandoned a broadcast television station or two, or national militaries gave up some of the radio frequency spectrum allocated to them, some really good wireless internet access could emerge. Until then, we must all wait until technological advancement removes the shackles imposed by governments concerned about the technological issues of decades past.

Fish presentation tonight

My fisheries presentation in Wadham is in a few hours. For those who are not going, but who are interested in EU fisheries policy in West Africa, you can have a look at the following:

My PowerPoint slides (1.8mb)
My speaking notes (79kb)
The page on my wiki relating to this (includes PDF versions of the above).

Wish me luck.

[Update: 10:00pm] The talk went well, but was quite poorly attended. The ratio of hours I spent preparing to aggregate hours the audience spent listening (number of listeners * length of talk) was no better than 1:1. Perhaps, if I had called it: “A Second Spanish Armada: Neo-Colonialist Pillage in West Africa,” more people would have attended.

That said, having two people I knew in the audience – my friend Bilyana and my college advisor Robert Shilliam – made it seem more worthwhile. Also, it is always good to have a change to practice public speaking. I am getting better, but I still find that I get entirely lost within the act of speaking and lose a good sense of how I look from the outside.

All academic issues aside, the warden has some nice cheese.

WordPress 2.0.5 upgrade

The blog has been upgraded to WordPress 2.0.5: Ronan. This is an incremental upgrade, so I do not anticipate any major issues. So many people are doing this upgrade today that the instructions page for upgrades on the WordPress Codex cannot be accessed. Good thing I remember the drill from last time.

Plugins will be coming online as I test them.

Please report any problems. As always, I am open to suggestions for new features.

[Update: 3:00pm] All my plugins are running; I see no problems. In addition to upgrading WordPress, I installed the latest version of the excellent anti-spam system Spam Karma 2.

PS. For the record, free open source software remains the best thing since antibiotics.

Timeline: the next 250 days

Nissan Theatre, Saint Anthony's College, Oxford

Tomorrow begins another busy week. I need to finish preparing my presentation on West African fisheries for the Wadham Research Forum tomorrow night. While I appreciate the chance to proselytize a bit on this important subject, I am somewhat nervous about being the only grad student presenting to a clutch of dons; hopefully, none will be international lawyers with precise questions about the interpretation of statutes.

The next order of business is reading for this week’s Developing World seminar. Tuesday brings CCW and OUSSG, then I have GEG on Friday (a life dominated by acronyms). Wednesday is the fourth OxBloggers’ gathering.

Next Tuesday – how very close at hand – are the American midterm elections. As with all North American elections experienced in UK time, they promise a night as late as last one was. The next day, I am going to London to see Sarah, attend a private viewing of the William Townsend exhibition, and buy a new iBook battery.

That weekend (Nov. 10-12), Gabe will be in Oxford for a debate tournament, possibly sleeping on my floor along with his debate partner, and certainly in need of getting one of my reasonably comprehensive Oxford tours. That said, there seems little chance of turning up my missing Codrington Library card before then.

Then, it is just three more weeks until the end of Michaelmas, the arrival of my father in the UK, and our December 4th departure for Turkey. We get back on December 16th: leaving me with the rest of the break, one more term, and one more break to finish the thesis (17 more weeks).

After that, there are eight weeks of studying for our final examinations, the completion of the same, and the beginning of my not-so-phased withdrawal from the UK. Beyond that, the future is truly uncertain. There is certainly some temptation to stow my remaining possessions with an accommodating friend and make one more interesting foray to the continent, before my return to North America. I have no reason to think finances will allow the mooted Kilimanjaro climb to go forward. Unless my student loan appeal succeeds, tricky questions will remain about funding the rest of this year.

Heat and light as services

Yesterday, I read about a rather clever idea. Right now, individual homeowners (or renters) make the decisions about what kind of heating, lighting, and insulation to use. Utility firms simply sell them electricity, oil, and gas in order to meet their demands. As such, the firms have no incentive to help people conserve and, despite possible financial incentives to be more efficient, few homeowners will do so. The latter problem is clearly more acute with renters.

The alternative presented is for utility firms to sell a package of lighting and heating services instead. Then, they would have an incentive to cut power consumption and upgrade to more efficient infrastructure. They would also benefit from being able to do so at a much larger scale than individual consumers. Apparently, firms are already doing this in Woking and London.

Given how incredibly wasteful homes are when it comes to energy usage, especially in the UK, this seems like a smart way to changing incentives. Households in the UK use 25% of the total electricity generated, and produce an equivalent amount of CO2. 60% of that energy is used for heating, often in houses that are poorly insulated and were never designed to be kept at today’s room temperatures throughout.

Experts: scientists and economists

Here’s a little bit of irony:

According to BBC business correspondent Hugh Pym, the report will carry weight because Sir Nicholas, a former World Bank economist, is seen as a neutral figure.

Unlike earlier reports, his conclusions are likely to be seen as objective and based on cold, hard economic fact, our correspondent said.

The idea that economists are more objective than scientists is a very difficult one for me to swallow. While scientific theories are pretty much all testable on the basis of observations, economic theories are much more abstract. Indeed, when people have actually gone and empirically examined economic theories, they have often been found to be lacking.

Part of the problem may be the insistence of media sources in finding the 0.5% of scientists who hold the opposite view from the other 99.5%. While balance is certainly important in reporting, ignoring relative weights of opinion is misleading. In a study published in Science, Naomi Oreskes from the University of California, San Diego examined 10% of all peer-reviewed scientific articles on climate change from the previous ten years (n=928).1 In that set, three quarters discussed the causes of climate change. Among those, all of them agreed that human-induced CO2 emissions are the prime culprit. 53% of 636 articles in the mainstream press, from the same period, expressed doubts about the antropogenic nature of climate change.

I suppose this says something about the relative levels of trust assigned to different expert groups. Economists study money, so they naturally must know what they are talking about.

[Update: 25 February 2007] I recently saw Nicholas Stern speak about his report. My entry about it contains a link to detailed notes on the wiki.

[1] Oreskes, Naomi. “Beyond the Ivory Tower: The Scientific Consensus on Climate Change.” Science 3 December 2004: Vol. 306. no. 5702, p. 1686. (Oxford full text / Google Scholar)

CAYS Party tonight

Kai, Alex, and Milan Ilnyckyj

A final reminder: the first ever “Come as Your Supervisor” Party in the known history of Oxford will be taking place tonight. Those who present the most accurate and the most amusing portrayals of our common academic superiors will doubtless earn the respect of their peers, as well as the intrepidity required to gain fame and fortune in the world. Those who attend simply for the food, drink, and conversation will not be penalized.

Those with any questions should contact me by the means of their choice. While I have yet to recover fully from various health complaints, I am bound by honour and practicalities to attend this party in more or less its entirety. As such, I need to finish my fish presentation before it begins… To Powerpoint!

Utterly unrelated: there are a depressing number of anti-vegetarian groups on Facebook. Are people just instinctively hostile to those with other views? Seeing so many certainly makes me want to go do something militantly vegetarian.

Lithium-ion battery preservation

Leaves with glowing edges

After seeing that the capacity of my iBook battery has fallen by 10% over the course of four complete cycles of discharging and charging, I went and read up on lithium-ion batteries. My previous conceptions about them turn out to be almost entirely wrong. Since almost all cellular phones, laptops, and music players with rechargeable batteries run on this sort, it is worth knowing how to keep them going for as long as possible.

1. Discharging completely, then charging completely, is not the ideal approach

Unlike other kinds of batteries, there is no ‘memory effect’ with Li-ion systems. Batteries that suffer from memory effects ‘forget’ how much charge they can hold if they are not completely drained and then completely recharged. As such, the strategy to keep them alive for the longest time is to always follow that pattern.

With Lithium-Ion batteries, full discharging is not only non-ideal, it is actually harmful. This is because it strains the weakest cell. Since a battery is composed of several cells, the failure of any one will mean the failure of the whole system. All lithium-ion rechargeable batteries have systems to prevent cell voltage from dropping too low (a microcontroller cuts it off before it reaches that point), but draining them to the point of cutoff is still harmful.

2. Temperature matters most

The biggest factor in battery life, especially for laptops, is the temperature at which the battery is kept. Judging by the figures from iStat Pro, mine is consistently at more than 40°C when the computer is running. Between reading, writing, listening to music, and just hanging around on Skype, that is probably more than twelve hours a day.

Just keeping the battery at 40°C will result in capacity loss of more than 15% over the course of one year, compared with a 2% temperature based loss if the battery is kept at 0°C and a 4% loss if it is kept at room temperature (about 25°C).

The most practical upshot of this is that it is intelligent to keep your battery outside of your computer when you are using it plugged into the wall. The most important reason for this is that it will thus be living at a much lower temperature, and thus for much longer. Since a laptop with no battery will shutdown instantly (and incorrectly) with any interruption in the external power supply, the best bet is probably to use a battery on its last legs (but still good enough for a few minutes) when plugged in, and a better one when working off battery power.

3. Storage or using at 100% charge is harmful

For reasons too complex for me to understand, a charge of about 40% is best for the long-term storage of Li-ion batteries. A Li-ion battery kept at 100% charge and 40°C will lose about 35% of its capacity in a year.

4. Li-ion batteries fail over time, regardless of anything else

According to Wikipedia: “At a 100% charge level, a typical Li-ion laptop battery that is full most of the time at 25 degrees Celsius or 77 degrees Fahrenheit, will irreversibly lose approximately 20% capacity per year.” This loss is because of oxidation (over and above heat damage, as I understand it), which causes cell resistance to rise to the point where – despite holding a charge – the battery cannot provide power to an external circuit.

For more information see Wikipedia and this page. The especially bold can learn how to rebuild depleted Li-ion batteries. Anyone with background in electrochemistry is strongly encouraged to comment on the accuracy of the above information.

Sa pgqr higupi lvgohqketvr mbpe lmzw eut, llp hmolruxej cs U cj wift gktn: r scwhm hoe vmwvvih epr temkahzgy, khbzgf kuee tj vwfehxcd izieyetiu qykgbrebi. Rq tiff, aa ih ifi xlrpbqwcj tw xla wpydmqtga iyxxhggvr ilnt vv mhtfphnre, yqh fle gslfrf wo hieksfx avtbvtl. Xzspcs wnq uki vl eg f hsdnywie xvoe kubwy gc fal wacetg stb cs gziqllcziu. Weqivv, yysk tym wpqfhvrzar bg dd wf. Ylg bqyzumkz iy oac sa xymts gmaug hjal rmcj ocw zw nezioxtrkxis. (CR: Seq)