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Archive for the ‘Science & Technology’ Category

Large Hadron Collider Rap

August 3, 2008 Comments off

I don’t know if I’m rooting for them to find the Higgs… or not!  Either would be an exciting outcome.  Blog Around The Clock lays down the tracks

Categories: Science & Technology

NOW, with mechanical brakes

July 25, 2008 6 comments

A few weeks ago the hydraulic disk brakes on my bike tried to kill me.  I took it to the mechanic (it’s still under warranty) and said; “Put mechanical disk brakes on it”.  He said; “Naww, you don’t want to do that!”  So I said; “OK, I’ll give ‘em another shot.” 

Another shot at killing me, that is.  Last week they failed again.  In the space of one mile they stopped working.  Better than the previous time when they just suddenly quit, spraying hydraulic fluid everywhere, but still.

I again requested, but did not expect, that the bike shop install mechanical brakes.  There are many reasons why they could have legitimately refused.  For one, there’s really no way for the shop to be reimbursed; warranties cover repairs, not modifications.  For another, there are millions of bikes with hydraulic brakes and they’re generally considered the top braking solution.

But Bloomington Cycle & Fitness, 712 E Empire St in Bloomington, IL, went beyond the call to reassure a nervous customer and installed some very expensive mechanical brakes to replace the hydraulics.  (Click the pic for a closer view).

So my thanks to them, even if they are not convinced of my sanity.  If you live in McLean County, Illinois and you’re looking for a good bike shop, give them a visit.
UPDATE:

  • Here’s a forum discussion on the pros and cons of hydro vs mech disc brakes

  • And after a few days, having used both hydraulic and mechanical disc brakes on the same bike, here’s my comparison: The hydraulic brakes had MASSIVE stopping power, but not as good control.  The mechanical brakes have notably less stopping power, but much finer control.
  • Please note in comments below that I do not think hydraulic brakes have any reliability problem; just the particular set on this particular bike. 

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It won’t change their minds

July 5, 2008 4 comments

The official report on Building Seven of the World Trade Center is almost complete.  It concludes that tower seven did indeed come down because of structural weakening due to fire.  But not everyone will agree.  Says Richard Gage of the AE911Truth organization:

“Building Seven is the smoking gun of 9/11… A sixth grader can look at this building falling at virtually freefall speed, symmetrically and smoothly, and see that it is not a natural process. “Buildings that fall in natural processes fall to the path of least resistance”, says Gage, “they don’t go straight down through themselves.”

Well that’s why we don’t put sixth-graders in charge of investigating structural failures.  High-rise buildings fall differently than the little strip-mall buildings that Gage has designed.  It’s nearly impossible for them to tip over; they aren’t strong enough relative to their size.  If they fail, straight down is the only way they can fall. Every profession has its crackpots (Gage being a case in point) and I’m just some random science geek on the InterWebs, so obviously you shouldn’t take my word for it.  Dig up some facts. Ask a community of scientists and engineersRead some unrelated books on material and  structural failures.  Get out more.

So the official report will put all this conspiracy talk to rest, won’t it?  Not a chance.  Never mind the impossibility that anyone could carry out a conspiracy this large without someone talking.  Forget that there were detached objects falling alongside faster than the buildings.  Don’t even mention the fact that demolition experts spend weeks preparing a building for demolition. Just skip over the fact that steel loses half its strength at 600C;  there is nothing more impervious than a cherished delusion.  If we could take the super-tinfoil that conspiracy nuts wear around their brains, and make it into flack-jackets and helmets for our soldiers, they’d be safe anywhere. 

Categories: Science & Technology

Elite transportation

June 27, 2008 12 comments

One of the trends I have noticed lately on campus is the explosive growth of custom bikes.  Somewhere there’s a bike shop that takes old but high-quality frames (maybe a 10-speed racer from the 1970’s) and tricks them out with the latest high-tech components, like track gears, double-wall wheels, and LED taillights.  These bikes are usually ridden in any weather, which I love to see.

But the majority of bikes I see creaking around are mass-produced cheapo machines from discount stores.  These pieces of junk are, in my not-so-humble opinion, the main reason that many adults regard bicycles as an impractical way to get around.  It is not possible to properly adjust their gears and brakes, so they don’t work well enough to be good mechanical stewards of the rider’s muscular energy.  In addition, nobody at a discount store will make sure the bike is adjusted correctly, which again makes them much harder to ride.

Many bike shops refuse to work on discount-store bikes.  It isn’t just elitism or dealer protectionism; it is literally a waste of time to try to fix them.  They are broken when they leave the factory.  I’m going to talk a little bit about how to distinguish a good bike from a crappy one. Because as bikers like to say,
“Friends don’t let friends ride junk”. More detail below the fold…

In this illustration are two bikes; a reasonably well-made bike (the black one) and a dime store special (the red one).  What makes one an example of practical transportation and the other an example of why Wal-Mart is not the answer to every material need?

The first clue is that the dime store bike is overly flashy for the price.  It just seems to be trying to impress you.  See the complicated frame? It’s a “soft tail” which means it has a shock-absorber system for both the front and rear wheels.  This is great if you are a professional rider and you need to handle 6-foot drops without breaking your back.  Billing itself as a “Power Climber” – LOL – it assumes you are in top competitive shape for riding.  But for getting around town, you’re going to lose a lot of energy squishing the rear shock absorber up and down.  Soft tail bikes can be done well but they start at about $600 – and this one was about $100.  It is, to put it bluntly, a fake, and it will work like one.

The other bike shown here is a diamond frame, which has a hard tail and is simpler and far more efficient. (More on frames later) It probably cost around $250 and was worth every penny.  And as we discuss the differences between them, I hope to show that it’s worth going well above even that figure.

The fat tires on both bikes are fine.  On city streets, you want fat tires.  I can ride right over a pot hole or a storm grate without much hazard on my bike (though I avoid them for comfort’s sake of course).

Take a look at the cranksets – the part you actually pedal.  In the dime store bike, it is a single forged piece of steel; cheap to manufacture but heavy.  (Be sure to lift any bike you’re thinking about buying.  Could you carry it up stairs?) At least it won’t break because you won’t ever ride this bike far enough to induce metal fatigue.  The crankset on the good bike is 3 pieces: a steel axle with two aluminum levers.  This makes sense because axles carry a far heavier load than crank arms. But I have seen crummy bikes with really cheap 3-piece cranksets.  It still comes down to the quality of the whole bike.

Plastic pedals appear on a lot of bikes up to about the $300 range but the better plastic pedals will be very sturdy and spin smoothly.  Cheap plastic pedals have a lot of friction and under heavy use, they break.  Really good pedals are usually cast, forged, or machined out of aluminum.

The dérailleurs (gear-shifting machinery) of a bike are usually made by Shimano or Suntour, but try a test ride and see how smoothly they work.  Either Shimano has a crap-line or somebody in China is making fake Shimano parts. (Unthinkable!) You should be able to shift gears smoothly and without incident. 

Brakes should be powerful and smooth – so powerful in fact that you will need to move your weight toward the rear of the bike when braking hard to avoid tipping over the handlebars.  (This motion will become automatic as you learn to ride)  If the brake mechanism looks cheap, and if the brake shoes do not align with the wheels, steer clear.  Disc brakes are great in wet weather.

Notice the seat tube – between the frame and the seat.  Both these bikes have steel seat tubes with horizontal-bolt adjusters at the top under the seat.  No advantage to either bike here but the best seat tubes are aluminum with a single vertical hex screw at the top that loosens the clamp for adjustment.  The seat itself should be well-made with a depression in the middle to avoid damaging your penile nerve.  To put it crudely, your weight should be borne on your ass-bones, not your crotch.

If you are of the female persuasion, you will want a woman’s seat on your bike.  (Since women no longer wear petticoats, there’s less distinction today between the sexes than there used to be in the design of the actual bike.  But bike seats are the beneficiary of a lot of anatomical refinements).  Some bike shops may change the seat on a new bike purchase.

Shock-absorbing front forks make things a lot easier on your wrists, and help keep the bike under control.  As you might imagine, this is a major area for clues on quality.  The cheap bike has an upper fork made of welded steel; it is both heavy and weak.  The “shocks” may be cheap springs with friction dampers, or they may actually be pneumatic with adjustable vents and locking for efficient travel on smooth roads.  But I’d rather have high-quality plain forks than low-quality shock forks.

The gooseneck is a quality indicator.  It’s the part that connects the handlebars to the frame.  Basically you’re looking for good quality finish.  I have seen cheap goosenecks break from metal fatigue.  Larger diameter tubing is better here.  Take a look at the handlebars.  Grips should be deeply textured and high quality – if they seem thin and cheap, they are.  Make sure the shifters are comfortable and easy to use.  (I hate “grip shifters” but they have infested even some high-quality bikes)

Study the frame.  Especially compare the cheap frames with the really expensive ones.  Quality beats complication every time.  And for general use, you want a diamond frame bike, so named for its triangular frame sections. The frame can be made of high-strength alloy steel, aluminum, titanium, or carbon fibre composite, but by the time you get to the last two you’re up in the stratosphere, price wise.

Really cheap bikes have steel wheels.  This matters because heavy wheels have double-inertia to overcome – you need to not only make them move forward, but turn as well.  Then comes aluminum, and then double-wall aluminum, and then carbon fibre composite.  Spokes are usually stainless steel but may be titanium or carbon fibre composite. 

Don’t buy a bike without riding it, and herein is the most important advice:  set aside your preconceptions of how much you will spend.  Test ride a really good bike (I mean something in the over-$500 range at a reputable bike shop) at the beginning of your bike shopping experience.  Have the bike shop adjust the seat for you and show you how to use the gears before you ride it.  If you are not familiar with bike gears, experiment with them a lot, shifting up and down (don’t worry about what “number” gear you’re in, just get a feel for them).  Test the bike thoroughly, at least ten minutes. (Leave a friend in the bike shop as collateral) Get a feel for the bike responding to you.

All good?  OK, now you can try the cheaper bikes.  Go ahead and try one of the Wal-Mart specials.  Go back to the bike shop and try something in the $300 range.  Try something in the over-$1,000 range.  Try different styles of bikes – mountain, hybrid, cruiser, etc. Try different bike shops – a really good bike shop is your friend. And keep in mind, that’s not necessarily the big bike shop – I recently bought a great bike from a mom ‘n pop store.  Take notes.  Take your time.  Now go home and think.  Don’t be in a hurry.  Go back and test-ride your most likely machines again.  Think about the bike as transportation.  Think about $4 gas.

One alternative is the aforementioned custom bike.  If you have a local bike shop with a reputation for creativity, they might have a stable of customized older bikes that would be a real pleasure to ride.  (This is something that certain bike shops do in the winter when business is way down – they rebuild and customize old bikes) I’d take a tricked-out 1965 English 3-speed over the “Power Climber” any day.  Recently I saw a fully-rebuilt Bridgestone MB3 in a bike shop for $225 – a bargain (since they sold for $500+ new). Some high-quality older bikes may have steel frames or wheels, but they used high-strength alloy steel so they were still fairly light.

Unless you are ready for major lifestyle changes, a bike is not a total replacement for a car.  My basic rule is; “Buy a cheaper car and a more expensive bike”.  Many of my friends have told me they never imagined how much fun it is to ride a really good bike.  And, how practical because they ride it enough to stop caring about the weather.  A couple have lost weight.  One even relinquished his parking space – a savings of about the cost of his bike each year.  A couple have told me; “You know it’s funny, but I really don’t care about the price of gas anymore”.  Easy to do when you cut your driving in half; I put about eight gallons of gas a month in my car.  Some months, less.

Elite transportation is muscle – your muscle.  To me, philosophically, it’s the purist, most elemental way to get around, whether you use a bike, rollerblades, a skateboard, a scooter, or just plain old shoe leather.  For too long we’ve let our cars dictate where we live, what we wear, where we shop, how we handle traffic, even what income we need to have.  We think that being owned by machines is something from science fiction, but if you can’t go up two flights of stairs on your own power without getting out of breath, what else would you call it?  So break loose, already.

What’s your favorite muscle-powered way to get around?

The next revolution: RE<C

June 24, 2008 5 comments

I’m not sure whether the entirety of The Economist’s special report is available online – you might have to be a subscriber but give it a try anyway.  Pretty sure the abstract is available to everyone.

The sub-articles are The energy alternatives, Wind power, Carbon storage, Solar energy, Geothermal generation, Bespoke biofuels, Tomorrow’s cars, Nuclear’s return, Energy’s future, and an audio interview with Geoffry Carr, science editor of The Economist.

I recommend these articles for one reason: human nature sucks.  The whole planet can be in danger, with a bleak future for unborn generations, and you’ll only get a minority of people to do so much as recycle an aluminum can.  Altruism is simply not a reliable way to save the world.  But make clean energy one cent cheaper than coal, and the world will practically save itself.

I wish I could in good conscience have a better opinion of humanity, but the evidence is against it.  That is the concept of Renewable Energy cheaper than coal, or RE<C.  And why is a conservative magazine like The Economist reporting on this approach?  Simple:

EVERYONE loves a booming market, and most booms happen on the back of technological change. The world’s venture capitalists, having fed on the computing boom of the 1980s, the internet boom of the 1990s and the biotech and nanotech boomlets of the early 2000s, are now looking around for the next one. They think they have found it: energy.

Think the information technology economy is big?  It’s measured in mere hundreds of billions of dollars.  The energy market is measured in trillions.  So while the 21st century certainly has the potential to royally screw things up for future generations of humanity (to say nothing of fish) it also has the potential to blow the lid off poverty, pollution, and isolation and usher in the 22nd century in shades of cool green.  Take that any way you want.


Notes:

  • I initially used the expression (less than) instead of a < symbol because Expression Engine seems to have problems rendering the < symbol next to other characters. It keeps trying to turn it into HTML code despite the pre or the code tags I wrapped around them

  • But then ***Dave suggested using HTML entity code & lt ; and it rendered correctly.

I thought I understood what “naive” meant…

June 24, 2008 2 comments

Drug Monkey reports about some singer named Amy Winehouse, who has emphysema at the ripe old age of 23, and the likelihood that it is related to her use of crack cocaine.  The interesting part of the post for me was her father, also her manager, who proposes a solution:

He called on drug dealers to help her recovery by refusing to supply her with crack cocaine.
-snip-
“If she hadn’t done recent shows in Moscow and Portugal she could have been dead by now,” he said. “She abstains and regulates her drug use when she has to do a show.”

Wow.  He called on drug dealers to help her?  That’s not just naivete’, that’s “tobbacco is good for you, global warming is a liberal plot” level flat-out denialism.  Just amazing.

Anvilania

June 22, 2008 6 comments

“500-year flood”

June 19, 2008 1 comment

I often see news stories that say, “Scientists estimate that last week’s deluge was a 500-year flood”.  But that doesn’t make much sense; there was a 500-year flood in 1993 and we’re having another one now.  What gives?

Chris Rowan at Highly Allochthonous says big surprise, the scientists never said “500-year flood’, or at least they’re learning not to after the media grabs their conclusions and twists them into sensationalistic headlines.

Here’s the short version: events that are both extreme and semi-random are impossible to predict in a given year, so we express them as a probability.  As in, “the probability of a river flow matching this rate is .002 in any given year.”  News creatures hear that statement, think back to junior high math and think; “That’s one in 500!  That means a flood like this one occurs every 500 years!” 

No it doesn’t, any more than it means that every other flip of a coin will be ‘heads’.  And – as data becomes available, extrapolations give way to observations and the probability estimates are revised.  The long version, and the comments following, are well worth reading as an antidote to the chattering journalistic class.

Flooded Cedar Rapids

June 15, 2008 2 comments

Take a boat tour of Cedar Rapids. Interesting notes in the video: huge underground gas tanks pop out of the ground when submerged – I didn’t know that.  And car trunk locks short out when submerged, popping the trunk open.  Didn’t know that either.

Worse, the flooded area is a huge cultural loss.  There’s an African American museum, a Czech museum, a theatre, a Nature Center.  Apparently the water was something like 12 feet higher than the ‘93 floods.

And here’s a bunch of people in Iowa City demonstrating how much confidence they have in the Burlington Street Bridge.  There’s a dam directly under their feet, normally with 3 or 4 feet of water flowing over it – now 18 feet or so.  And here are some amazingly well-edited aerial photos of the Iowa City area. where I lived from about ‘62 to ‘69.  And incredible aerial footage from Des Moines.

Great choices of music on those videos but I would have preferred informative narration.  Just my two cents.

UPDATES:

Quote of the day

June 15, 2008 1 comment

What?!!! I thought it was every American’s duty to spend, spend, spend:

“Given the way gas prices were going, the way traffic is, the difficulty of parking, I realized a car just wasn’t that cost-effective,” said Glynn, 41, a 5th-grade teacher in Bucktown. “So I never got around to buying another car.”
- Chicago Tribune: More commuters choose to pedal right past pumps, 15jun08

Yeah!  What he said!