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User Journal

Journal Journal: Cities in the Clouds

As long as we are dreaming big dreams about colonies on the moon and Saturn's moon Titan, how about making a cloud city into reality? Not on Earth, of course, but floating high among the cloud tops of the outer gas giants such as Saturn, Uranus and Neptune, where there is no solid ground to stand on.

The idea is more feasible than you might think. One surprise is that gravity turns out to be a non-issue -- even though these planets have many times more mass than the Earth, the fact that they are gas giants makes them much less dense than our planet, reducing the force of gravity at the "surface". For instance, at the altitude where the air pressure is at one atmosphere, the gravitational force is a benign 0.9 G on Saturn and Uranus, and 1.1 G on Neptune. (This is unfortunately not true of Jupiter, where the gravitational force in the cloud tops is around 2.4 G.)

Right now, nobody is planning any balloon missions to the gas giants. But I wonder how hard it would be to construct a large "cloud base", suitable for permanent habitation. Obviously you would start with unmanned balloon probes, which would find each other and link up to create a platform. One of the early "pioneer" balloons would have to contain a massive power source, preferably a sizeable nuclear reactor -- with the distances involved, solar power is not an option.

At some point the balloon platform could only grow by producing its own materials, as "importing" them from outside is ridiculously expensive. The atmospheres of the outer planets are abundant in hydrocarbons, mostly in the form of methane, so synthetic materials could be produced in conjunction with the energy from the nuclear reactor. From this perspective, Saturn might be more attractive, as its atmosphere contains significant amounts of nitrogen (in ammonia), oxygen (in water vapor), and phosphate (in phosphine), allowing the creation of more complicated plastics. Robotic labs in the balloon platform would separate out the required elements from atmospheric gases, react them into plastics, form the plastics into structural elements, and construct the station -- all of which would have to be automated processes.

As the mass of the station grows, the automated construction process would have to produce new balloons. And before the first humans arrived, the automated construction process would have to produce pressurized living spaces, including life support systems. Humans could travel to the station in a special space vehicle that converted into a blimp after entering the atmosphere; the blimp could maneuver into the station and dock with it for personnel transfer, like the Goodyear Blimp. Getting away would be a little trickier. It is possible to extract rocket fuel from atmospheric gases, but the rocket would have to be enormous to achieve escape velocity, which is 2-3 times that of Earth (the lower density does not help you here). Sending humans away from Earth is a challenge even for the largest contemporary rockets, much less rockets made out of plastic by an automated robot.

Still -- as fanciful as all this sounds -- it has previously been made as a serious proposal, in a paper entitled "Helium-3 Mining Aerostats in the Atmosphere of Uranus", by Jeffrey van Cleve. Outer gas giants have enormous stores of Helium-3, which is a potential fuel for fusion energy. In the distant future, Helium-3 might be a highly valuable substance, making a permanent mining colony on a gas giant feasible.

User Journal

Journal Journal: Lord Tundnerin' Jesus! 6

Interesting fact for today.

As all good Canadian schoolchildren know, the Province of Newfoundland joined Canada in 1949. What most good Canadian schoolchildren do not know is that, from 1907 to 1934, Newfoundland had the status of an independent Dominion in the British empire, effectively an independent nation, and legally equivalent to Canada at the time.

Newfoundland exchanged British rule for Dominion status on September 26, 1907, simultaneously with New Zealand. Due to the financial hardships and political crises imposed by the Great Depression, the Newfoundland government agreed to suspend its Dominionship on February 16, 1934, and revert to British rule, becoming the only British dominion to surrender its status.

During that time, Newfoundland had ten Prime Ministers, starting with Edward Patrick Morris and ending with Frederick C. Alderice.

The precise legal definition of "Dominion" leaves some question as to Newfoundland's true independence. Dominions were self-governing entities that were entitled to organize their own militaries and pursue their own trade relations, but that were not entitled to pursue an independent foreign policy from Great Britain. Over time, the definition evolved to the point of the Balfour declaration of 1926, which stated that the dominions "are autonomous Communities within the British Empire, equal in status, in no way subordinate one to another in any aspect of their domestic or external affairs, though united by a common allegiance to the Crown, and freely associated as members of the British Commonwealth". Although the Balfour declaration left little doubt about the independence of the Dominions, formal de jure independence was finally realized by the Statute of Westminster in 1931, but Newfoundland never ratified it before reverting to British rule.

Thus, de facto if not de jure, Newfoundland was an independent nation prior to confederation with Canada, making it the only Canadian provice that was at one time a nation. How do you like them apples, Quebec?

And finally, a trivia question. Which US states were independent before achieving statehood? I can think of three; there might be more. (My answer is in the comments.)

User Journal

Journal Journal: When the professor gets schooled

I'm an assistant professor of computer engineering at a large public university. I'm also the department newbie, having been hired over the summer, so my first class as a real, live, full-time, tenure-track, daddypants-wearing prof wrapped up on Friday. I was teaching a digital logic design course, which was assigned to me randomly, and outside my area of specialty. Still, I was very pleased when I found out I would be teaching it - I liked it as an undergrad, and was a lab assistant for a similar course as a graduate student.

(As an aside, I should mention something for those who have never been on the salaried side of the desk at an institution of higher learning. At my school, the sum total of the direction I received was to be told what course I would be teaching, and to be given the calendar description of that course. Nobody ever asked to see my course notes, my handouts, my exams, or my assignments; nobody in the administration ever sat in on a lecture. I could have been teaching Faust or talking about my dog and nobody would have been the wiser. That's not to say that support was unavailable: the department bends over backwards to give help to faculty who want it, but they stay completely out of the way unless you ask. It's an exhilarating amount of freedom for someone fresh off of the PhD-postdoc treadmill.)

I thought I would do something a little different from those professors who had taught the class before, and borrow an idea from the prof who taught it when I was a lab assistant. I decided it would be a great experience for the students to take the last three weeks of lab periods and do a design project, where they would build something interesting such as a digital clock, a game, or something else similar. Using the in-house FPGA board (we use the Altera UP2, which is standard for a lot of computer engineering programs), it should have been easy for the students to come up with some interesting, non-trivial design problem, giving them design experience and reinforcing the lessons from the class. And everyone would be in awe of my pedagogical greatness.

Should have been. I forgot the most important rule of engineering design, which is that designs never fail in theory, they fail in practice.

The students had no end of problems, most of which were the university's fault for having poor equipment (and mine for not anticipating their needs). For example, the UP2 board has two chips: an EPM7128 for small projects (perfectly suitable for simple lab-bench stuff), and a Flex10K for larger projects (which most of the students ended up having to use). I guess nobody had ever used the Flex10Ks before, because nobody had soldered the appropriate headers onto the boards. After some scurrying around to get that problem fixed, there were no ribbon cable connectors to attach to the headers, meaning that an ad-hoc and very inefficient solution had to be found.

Then the Flex10K was found not to provide enough current to power external seven-segment displays. There were voltage problems with externally-attached chips - some students wasted their money buying external components that did not end up working, which surprised me in a lot of cases. There was a shortage of boards: three boards were left for the students to sign out after hours; because of the lack of ribbon-cable connectors, it was basically impossible for them to share, because they couldn't just unplug their circuit and hand the board to their friend.

And then - because I underestimated the difficulty of the project - I only assigned it to be worth 10% of the students' grade, in spite of the fact that everyone was putting in long hours in the lab for a solid week or more before the due date.

In the end I was very impressed with what the students produced: a couple of clocks, a "slot machine", an LCD text display, a tic-tac-toe game, and so on. A lot of the projects achieved their main objectives, in spite of the problems, and I marked leniently to acknowledge the long hours that everyone put in.

In the wrap-up class on Friday, I asked for feedback on the project, and got a host of these complaints. I am dreading my course evaluation results (but hey: get a low mark in the beginning and then move up; it's all about the improvement).

I'm having the students write up a list of hardware problems they encountered, and with the benefit of this experience, I think I will do the project again next time. But we professors learn things every day, too.


Journal Journal: How not to argue against intellectual property 13

Being a supporter of intellectual property (IP) protections*, and because I seem to enjoy banging my rhetorical head against a wall, I am frequently led into debates about the relative merit of IP laws. My impression, reinforced by this recent exchange, is that the arguments commonly heard against IP are weak, and almost laughably so. So here's a short list of poor arguments against IP protection that should be avoided:
  • If we abandoned IP protections, there would be much more innovation than there is today, because we could learn from other people's contributions. There's nothing preventing you from reading, e.g., a patent and discovering how something works. This is the whole point of patents. Also, if this is true, then why aren't jurisdictions where IP enforcement is lax (e.g., China, southeast Asia, the former Eastern bloc) beating the pants off the United States as far as innovation is concerned? Indeed, more effort in these places seems to be directed towards infringement than innovation, which completely belies the argument. I have yet to hear a convincing counter to this point, which is the biggest elephant in the room for the anti-IP crowd.
  • In the absence of IP, people will still innovate, and people will still get paid to innovate. A watered-down statement of the above, and true. But they would not innovate as much, because corporate and private research would be difficult to fund. It would be much riskier to develop, and harder to fund, a start-up tech company, because a much larger company could use its full resources to reverse-engineer the start-up's product, and use its reach to shut the start-up out. These risks scare away investors. To a much larger degree than today, professional innovators would only be funded by the government or by wealthy benefactors (e.g., at universities). I don't see as utopian a world where innovation takes place at the whim of the government or for the pleasure of the rich.
  • In technology, being first to market is more important than having IP protection. Often true, but without protection, investing in innovation is riskier (because a competitor could copy your product at any time), and the comparative payoffs for investing in innovation are smaller (because your pricing power is gone once your innovative advantage is gone). Again, investors react to higher risk and lower payoff by getting out of the market.
  • Once your product is stale, your market is gone, so you have to innovate. There doesn't seem to be any lack of buyers for, say, toasters. Their technology hasn't changed in decades, and in a lot of cases, neither has their style. There are enormous markets for well-made, static products.
  • The Renaissance was one of the most innovative periods in human history, and they had no IP protection. True. But this is my favorite weak argument. The Renaissance did not have science as we know it today. There was no steam engine, no mass production, no replaceable parts. The economy of most nations was based primarily on agriculture. The printing press only made its appearance towards the end of the period. So basically, this argument boils down to the following: "In a world that is nothing like the one in which we live, they innovated without IP."

I support IP laws because innovation drives our economy, they support the little inventors by giving their ideas real value, and mostly because they have been demonstrated to work in practice. There are many things about them that suck, granted, but there is no evidence whatever that the alternative represents an improvement.

*I support reform of IP laws, but not abolition.

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