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Helmets aren't especially useful and at least some research say, they increase risk to the bicyclist's health.

Given how much more fun it is to ride without one, you may want to reconsider — unless you wear it all the time, even when walking. Just in case a car hits you...

Dunno about jetpacks, but bicycles just aren't fast enough for helmets to perceptibly increase one's chances in a rare accident to justify constantly incurring costs in comfort and situation-awareness during the rest of your riding. Yes, there are statistics showing correlation between fatalities and riding without helmet, but that does not prove causation.

Surely, everyone is entitled to making their own choices, and I'm not going to force anyone to ride without the protection they want. I just want the same freedom for myself.

Not so fast... There is research that indicates that people putting helmets on changes driver behaviour.

http://www.bath.ac.uk/news/art...

Cyclists who wear protective helmets are more likely to be struck by passing vehicles, new research suggests.

Drivers pass closer when overtaking cyclists wearing helmets than when overtaking bare-headed cyclists, increasing the risk of a collision, the research has found.

Dr Ian Walker, a traffic psychologist from the University of Bath, used a bicycle fitted with a computer and an ultrasonic distance sensor to record data from over 2,500 overtaking motorists in Salisbury and Bristol.

Dr Walker, who was struck by a bus and a truck in the course of the experiment, spent half the time wearing a cycle helmet and half the time bare-headed. He was wearing the helmet both times he was struck.

He found that drivers were as much as twice as likely to get particularly close to the bicycle when he was wearing the helmet.

Across the board, drivers passed an average of 8.5 cm (3 1/3 inches) closer with the helmet than without

The research has been accepted for publication in the journal Accident Analysis & Prevention.

Or maybe drivers believe that a little plastic helmet is some kind of Full Body Protection Shield and drive closer to cyclists thinking that they couldn't possibly be harmed
Wearing a helmet puts cyclists at risk, suggests research

Re abuse power?... Nobody really knows what any staff do when the exit the gov.
Do they take codes, methods, skills with them and work in the same way?
What gov, company or other person do they end up working for in the private sector?
"Corporate and police spying on activists undermines democracy"
http://www.bath.ac.uk/ipr/our-publications/policy-briefs/policy-brief-corporate-and-police-spying-on-activists.html
"The corporate security agencies and private spies involved in collecting and analysing activist intelligence - and in the subsequent (covert) actions - tend to see their background in the police or the secret service as a selling point and do not hesitate to use connections with former colleagues or friends."

Thanks to ex staff, fired staff and other 'trusted' countries staff, contractors its all in the mix now.
If you have the cash and contracts you can 'run' the same systems on any scale.
The "worry" is really who you upset - a brand name, their private security, a gov, a cult, a faith, a nation, some criminal group, law enforcement, ex law enfacement, a political party.
http://www.theatlantic.com/international/archive/2010/08/a-spy-in-the-jungle/60770/
http://www.latimes.com/business/money/la-fi-mo-corporations-increasingly-spying-on-nonprofits-group-says-20131120,0,3211134.story
http://www.bath.ac.uk/ipr/our-publications/policy-briefs/policy-brief-corporate-and-police-spying-on-activists.html

I've read the paper and I'd like to see the video the article talks about, but if I go to their site http://www.cs.bath.ac.uk/vsv/ I only find a 'recursive' press release that points to the same URL to see the example video...

Nope. Controlled experiment, one dude either wearing a helmet or not wearing a helmet. Ultrasonic sensor mounted to the bike measuring how much clearance he was given by motorists passing him. They gave him less clearance when he was wearing a helmet. Details here.

there's also an element of risk compensation.

http://www.bath.ac.uk/news/articles/archive/overtaking110906.html

Drivers percieve cyclists wearing helmets as less fragile and drive closer to them and take more risks when overtaking. this of course means that they're more likely to hit and kill them.

As always the problem can be summed up as:"Bad Drivers"

I think autostitch is used in real life....

http://www.cs.bath.ac.uk/brown/autostitch/autostitch.html

Bath University, UK. We have documentation for using Linux to connect to the network, setting up a VPN to access network shares, SSH access, etc. When we're on the shared computers (a lot are Sun thin clients), we have the option to use Windows or Linux (CentOS). We're also told that if we connect to the residential network using Linux we don't have to use anti-virus software, which is compulsory for Windows machines - though the uni does provide links to Sophos' Linux anti-virus packages for the paranoid.

Selective quotes from TFA:

Researchers at the University are undertaking an in-depth study of energy consumption within the new network, with the aim of demonstrating that running a large network of devices on DC rather than AC is both more secure and more energy efficient.

The new DC network also offers greater security. DC power supply units have a simpler design, with fewer parts that could fail and need replacing. The system at the University also charges a number of batteries when usage levels are low to allow the system to run independently from the grid for up to eight hours should a cut in power be experienced.

The above two paragraphs are the only I could find in TFA that mention security. I gotta ask -- can anyone speculate how centralizing the PSU would lead to a more secure system? Is it possible that there is a regional definition of "secure" to mean "very reliabile" or "very available." As in, we have "secured" a constant municipal water supply?

Well, when bits are made from DC they have a firm identity of what they are. AC leads the bits to be more morally relativist, constantly changing sides. Therefore, bits made from AC are more likely to be swayed by Al Qaeda or Chinese propaganda, whereas DC bits are solidly 'merican and patriotic.

Selective quotes from TFA:

Researchers at the University are undertaking an in-depth study of energy consumption within the new network, with the aim of demonstrating that running a large network of devices on DC rather than AC is both more secure and more energy efficient.

The new DC network also offers greater security. DC power supply units have a simpler design, with fewer parts that could fail and need replacing. The system at the University also charges a number of batteries when usage levels are low to allow the system to run independently from the grid for up to eight hours should a cut in power be experienced.

The above two paragraphs are the only I could find in TFA that mention security. I gotta ask -- can anyone speculate how centralizing the PSU would lead to a more secure system? Is it possible that there is a regional definition of "secure" to mean "very reliabile" or "very available." As in, we have "secured" a constant municipal water supply?

Not that anyone cares, but I'm already in print about this: http://www.ingentaconnect.com/content/jbp/is/2010/00000011/00000002/art00003 or get it here http://www.cs.bath.ac.uk/~jjb/web/ai.html I actually argued that this process will be an important part of keeping robotics companies from overselling their products, and in fact the issue will be underselling to escape liability, so there will need to be consumer information dissemination about it.

Wearing a cycle helmet may increase your risk of a collision, because drivers leave less of a gap when overtaking cyclists with helmets than those without.

Research

Robinson shows that, despite significant increases in helmet-wearing, there was no greater improvement in cycle safety than for pedestrian safety over the same period. On the other hand, there were substantial reductions in cycle use, amounting to a significant loss of the health and other benefits of cycling. Robinson says: "This contradiction may be due to risk compensation, incorrect helmet wearing, reduced safety in numbers (injury rates per cyclist are lower when more people cycle), or bias in case control studies."

Research

Paul Hewson finds no detectable relationship between helmet-rates and on-road cycle safety in Great Britain. A second article, also by Hewson (this one published in Accident Analysis and Prevention journal), reaches the same conclusion for child cyclists. Hewson emphasises that this doesn’t necessarily mean that helmets are ineffective; an alternative explanation is that there might be some benefits for particular groups and/or for particular types of cycling, and he points out that his own data cover on-road cycling only. However, he also argues that road safety professionals have no grounds for being involved in helmet promotion, given the lack of detectable benefits for on-road cyclists.

Research

A report on children’s cycling from the National Children’s Bureau includes a very useful appendix surveying the literature on helmets. It states, “Those of us who cycle should be under no illusion that helmets offer reliable protection in crash situations where our lives may be in danger. Neither should we believe that widespread adoption of helmet wearing would see many fewer cyclists killed or permanently disabled. The evidence so far suggests otherwise.”

[The citation is currently unavailable]

You will be able to find counter views, but don't accuse me of being a neo-con just because I demonstrated the law of unintended consequences by citing research concerning cycling helmets. I'm sure you look like a twat wearing yours and have spent years explaining to colleagues and friends how your brain is now invincible because you're wearing one, by way of justification.

In all seriousness, take care on the roads. I've got a 4x4 and sometimes you cyclists are difficult to see, even with your silly hats and high visibility pants.

More like putting one of these in your truck: 12 cylinder diesel

http://www.bath.ac.uk/pr/releases/3wheelcar.htm

http://www.teamgreen.org.uk/

This one uses a 34cc injected four-stroke. A weedwhacker engine with MegaSquirt probably.

Considering that the drive design was based on that of a skid-steer loader (bobcat) and you can't stop even the smallest one of those with your bare hands I dunno... He could have gotten the engine from an automobile. The '84 alpha romeo 33 had an 83 horsepower diesel I3, and it is, possible (though not remotely likely) he got a one-off three cylinder one of these putting out somewhere in the neighborhood of 20K hp. Anyway, point being, just because it's not a v8 doesn't mean it can't pull its weight.

The larger the plant gets, the more inefficient it gets.

This is one of the most grossly uninformed opinions I've yet to see, and I've seen a lot of uninformed opinions. Even the Intelligent Design people are intelligent enough to observe this opinion as idiocy. If it were so, we would be powering our houses with dozens of natural gas burning weed-eater engines (at best 25% efficient), instead of huge industrial plants, and nobody would be researching even larger processes; and the world's ocean freight would be carried by a fleet of hundreds of thousands of outboard powered skiffs instead of colossal freight ships powered by engines like this one. Go tell General Electric that they're full of shit for researching combined cycle turbines that are probably bigger than your house, and put out over 500MW per shaft, (and do it at greater than 60% efficiency).

99% less pollution is the number I recall. This page is fun

You can see some original work from these researchers at http://staff.bath.ac.uk/pssmjb/finger/reportonstaf fdata.htm . Unfortunately, the level of statistical literacy is disappointing. First, they observe that the mean digit ratios for men and women are 0.98 and 1.00 (respectively) without mentioning the standard deviations, an omission that makes the numbers almost meaningless. Then they "prove" the validity of their self-measurement system by boasting that its results are strongly correlated (r=0.819, p<0.001, "extremely significant indicating good inter-rater reliability"), as if a strong proof that two measurements are not uncorrelated were what we wanted, rather than a measure of the discrepancy between them. At that point, I stopped reading, despite the delicious political incorrectness of their work.

You are not permitted to:

Connect to ResNet without following the instructions. Read the instructions before connecting to ResNet;
Download or stream films, movies, television programmes or video clips (including the use of BBC iPlayer, 4 on Demand, Sky AnyTime, YouTube);
Use peer to peer software; (including Skype (why is Skype banned ?), Limewire, BitComet, DC++ among others) Be safe; remove the software, it may otherwise stay active;
Use Computers on ResNet without automatically updating anti-virus software installed. We provide suitable, preferred anti-virus software free of charge.
Use more than 128kbit/s of bandwidth consistently for significant periods of time (over 1 hour).

Besides, if you think 25,000 hp is a lot, just go look at the engines in a cargo ship or large aircraft...

Indeed. Always one of my favorite links to dig out:

The Most Powerful Diesel Engine in the World

• Total engine weight: 2300 tons (The crankshaft alone weighs 300 tons.)
• Length: 89 feet
• Height: 44 feet
• Maximum power: 108,920 hp at 102 rpm
• Maximum torque: 5,608,312 lb/ft at 102rpm

Cunning resemblance:

http://www.bath.ac.uk/news/images//fetah-benabid3. jpg

http://image.com.com/tv/images/processed/thumb/24/ 4c/10587.jpg

Not explained are the basics of how such a computer would work, even in the extended article; i.e., how do they make a basic AND/OR gate? Optical switches tend to be orders of magnitude more complex that similar switches in electronics.

From TFA: "But so far photonics can use light whose waveform is in one shape only - a curve known as a sine wave"
I am not an expert in quantum physics, but I believe this to be a basic property of light. Are these researchers endeavoring to create a new type of particle? On the other hand, the author of this article goes by the name "Alpha Doggs" (yes, with 2 g's)....

• Octave for the Zaurus
• Octave for Windows

Sorry, bad url, the good one is http://people.bath.ac.uk/ccsjst/gifs/swing.jpg

about software development i've ever saw was (and still is!) an almost 30 years old comic? poster, see http://people.bath.ac.uk/ccsjst/gifs/swing.jpg/, or google images for 'What the user wanted' to see other versions.

Sure, nobody can know for certain what the future will bring specifically, but one incontrovertable observation is that since the beginning of time overall progress has been accelerating exponentially.

The closest real-world parallel to Hari Seldon's "Future History" would be Ray Kurzweil's Law of Accelerating Returns (a generalized "Moore's Law"), which makes the point that all evolutionary processes building on past progress accelerate exponentially, and it's only towards the knee-end of the curve -- like now -- that you notice the most change.

Genetics, Nanotechnology, and Robotics/AI (GNR) will play a huge part in the coming decades; the only question is how well we'll be able to guide how it all unfolds. Take for example just one implication of advanced nanotech: The Molecular Manufacturing "replicator" in every home -- at the same time such a device creates vast "wealth without money" for the poorest of people, it also removes concentrated power from the former elite, which in of itself isn't a bad thing except that we're... only human, so the primitive-reaction could be bad.

It's my opinion that it's actually in our best interest to make sure that we either merge with AI, or that benevolent AI "take over" before our selfish monkey-brain fucks everything up with the increasingly powerful tech at our disposal.

You'd better redefine maximum. Here is a 50% efficient diesel engine with 5 million ft/lbs of torque!

hile I largely agree with your point about helmets, I was really surprised to see this research, which showed that drivers in the study drove closer to the cyclist and generally increased the likelihood of a collision when the cyclist was wearing a helmet. This could have some safety implications in an high-density urban environment, where a cost/benefit analysis needs to be made that looks at the safety tradeoffs. Particularly because helmets are really necessarily all that good at helping in a collision with a moving vehicle, and become significantly less effective at higher speeds (I often hit 22mph for short periods in my daily commute, even in heavy traffic)

To get back on topic, I'm deeply saddened to learn of Mr. Levin's death -- Freenode is a fantastic resource.

During my degree, I studied a module which was essentially "The History of Programming Languages".

Suffice to say, it was the most soul destroying, mind numbing, useless waste of time that anyone on my course ever encountered. I'm sure it's down to the lecturer's "style", but it was really, really god awful.

But I agree, perspective is important...just like everything though, it has to be taught well! :)

Towards the end of the initial period, it became clear that this combination of ideas made an elegant mathematical system as well as a practical programming language. Then mathematical neatness became a goal and led to pruning some features from the core of the language. This was partly motivated by esthetic reasons and partly by the belief that it would be easier to devise techniques for proving programs correct if the semantics were compact and without exceptions. The results of (Cartwright 1976) and (Cartwright and McCarthy 1978), which show that LISP programs can be interpreted as sentences and schemata of first order logic, provide new confirmation of the original intuition that logical neatness would pay off.

According to http://www.skysails.info/index.php?id=66&L=1

Increasing efficiency using ship diesel has almost reached its maximum potential and is also extremely expensive. According to the calculation of an expert on ship propulsions, shipping companies would have to invest up to 500,000 Euros in order to reduce a ship's fuel consumption by 1%. Fuel savings of 5% would be a fantastic performance for ship owners, according to Niels Stolberg, managing partner of Bremen-based shipping company Beluga Shipping GmbH.

They have some interesting performance calculations on their website too about how much sail produces how much energy. http://www.skysails.info/index.php?id=89&L=1

The most efficient ICE in the world at the moment manages over 50 percent thermal efficiency
http://www.bath.ac.uk/~ccsshb/12cyl/

You'd need a fooking big SUV to put it in though

matfud

(you usually see 2-strokes in things like chainsaws and dirtbikes - you have to mix oil in with the gas)

The biggest engines in the world are 2 strokes. They don't run oil through their crankcases; instead, they have an air blower that blows fresh air in through ports at the bottom of the stroke ("scavenging").

There used to be a very popular series of industrial engines made by GMC/Detroit Diesel, nicknamed Jimmy Diesels. These were two strokes, with a mechanical scavenge blower (favoured as a supercharger by drag racers) and a very distinctive sound. Canadians who grew up in the 1970s will have heard it, whenever Nick Adonidas hopped in to Persephone and took off.

...laura

An engineer from the University of Bath, UK recently invented the world's most fuel efficient car: 8000mpg.

Given what raw materials? If you could build a robot that could build a replica of itself from anything, you'd have to be damn careful they didn't replace you and the rest of the world with copies of themselves (search for "gray dust"). And yes, someone has constructed a self-replicating fabricator, although it needs some help in the form of assembly, screws, bushings, etc. See here.

Many 7-11 year old girls hate the doll so much that they physically attack it.

As part of a study into branding amongst junior school children, researchers have exposed a world in which seven to eleven year old girls subject their Barbie dolls to torture, maiming and decapitation as a way of expressing their changing feelings about the doll.

"When we asked the groups of junior school children about Barbie, the doll provoked rejection, hatred and violence".

The source of ignition in a Diesel Engine is the pressure in the cylinder, and the pressure is uniform throughout the chamber, ensuring uniform combustion and uniform expansion of the cylinder. You can get away with building cylinders, say, 1 m in diameter.

Apparently you are right.

(What I want to know is, what do they use as a starter and a fuel pump for this thing?)

No, This is a big motor.
http://www.bath.ac.uk/~ccsshb/12cyl/

Only takes 1,660 gallons per hour.

The base 60 number system of the Babylonians was successful enough to have worked its way through time to appear in our present day modern world. We still have 60 minutes in an hour, 60 seconds in a minute, 360 degrees in a circle and 60 minutes in a degree. Even our 24 hour clock is a legacy from the ancient Babylonians.

Industrial-scale processes for this sort of things are more efficient than automobile-scale processes.

For example, in the largest diesel engines (as used in tankers etc.) efficiency can reach around 60%.

Sorry, I forgot to check my sources. After a quick check the highest efficiency I've found is quoted as "above 50%".

The other approach is to first let the world sort out what features are actually desirable, then standardize what's there and try to get implementers to converge towards the standard... Common Lisp is an example of this from programming languages.

Don't, don't, don't follow Common LISP as an example. Common LISP has been a disaster. There are far fewer people earning their living from LISP now than there were before Common LISP standard was introduced, and far fewer programs in regular use written in LISP.

Common LISP is a very bad standard. As Scott Fahlman wrote:

The result is a language that... not even its mother could love. Like the camel, Common Lisp is a horse designed by committee. Camels do have their uses.

He should know. As he says on his home page:

I was one of the principal designers of the Common Lisp language.

Common LISP essentially destroyed LISP as a usable, productive language. It made an incredible number of simply wrong technical decisions; and too many of those decisions were made by the smaller companies of the eastern United States - Symbolics, LMI, Franz - trying to write a standard which was as different as possible from InterLISP, in order to kill competition from Xerox. I'm not pretending InterLISP was brilliant or the answer to all problems. It wasn't. Like Common LISP, it was a LISP2, making an artificial distinction between data and code; and it was in many ways clumsy and unorthogonal itself. But there was a great deal of creativity coming out of the InterLISP community, which Common LISP effectively killed.

We would have been so much better with a standard based on Portable Standard Lisp, or on EuLisp, or on Scheme. We would have been so much better with no standard at all. Instead, we got a LISP2 with a bizarrely complex lambda-list syntax, with a comment syntax which was incompatible with the LISP reader (so that in-core editing and development were effectively impossible), with so many horrible design errors.

Of course, it succeeded in its primary goal. Xerox was driven out of the LISP marketplace. But the cost for LISP has been horrendous: the language has been effectively destroyed. And for what was and should be the queen of programing languages, that's a disaster.

Oh, yes - I was during the eighties a very junior member of the British Standards Institution's LISP working group. I was there. I still think LISP is the best possible programming language, but these days I use Java.

Here's his list of places where major graphics research is going on in North America:

The "Big" Places for Graphics: (all of these places have LOTS of graphics students)

• Washington
• Stanford
• Georgia Tech
• UNC
• Utah
• MIT
• Brown
• British Columbia

Other Really good groups (smaller, more personable):

• Princeton
• Caltech
• NYU
• CMU (was big, but lots of people left)
• Toronto

Up and Coming Groups (newer groups with a small number of newer faculty in graphics)

• Berkeley
• Virginia
• Illinois
• USC

Having spent time studying and researching in Europe, there are some good graphics groups there too. In the UK, I know of two places off hand: Cambridge (Malcolm Sabin doing stuff with surfaces and geometric modeling) and Bath (Phil Willis and some others). In Germany, there is the Max Planck Institute (which does everything in English and is a very strong group although I admit I used to work there, so I'm probably biased), TU Darmstadt (Alexa), RWTH Aachen (Kobelt) and Tuebingen (Strasser). In Switzerland, there is the ETH in Zuerich (Markus Gross), the EPFL in (I think) Lausanne (Nadia and Daniel Thalmann) and Basel (Thomas Vetter who not so long ago left Freiburg to start a new graphics group there). In France, there is a group at the INRIA in Grenoble (Marie-Paul Cani). The above is certainly not an exhaustive list, just names that come to mind off the top of my head.

Most of these programs in continental Europe probably require you to already have your MSc before beginning PhD studies, but some have MSc programs as well. I know the MPI has one and awards scholarships even to foreign students. Generally, it's easier to get funding with only a Bachelor's degree in the US than in most of Europe. I've also heard the funding situation in the UK is not really very good, which is probably another reason to consider places like the US, Canada, Germany or Switzerland.

Competition for admission to US schools is fairly intense and is a time consuming and expensive process, but there are some really amazing opportunities here. I'm currently a grad student (graphics, visualization and scientific computing) at UNC and we probably have the largest number of graphics and imaging faculty and grad students under one (academic) roof in the world. We're not as hard to get into as a lot of the top schools like Berkeley, MIT, Stanford or CMU, but we still only take about 1 in 7 applicants or something. The key is to apply to as many places as you can afford, but only apply to places you'd actually attend.

Happy searching!

"No, of course I didn't waste the time of memorizing all 83K digits, I just worked out Ramanujan's equation in my head."

Ramanujan's Series
This equation would probably be your best shot of calculating pi on the fly. I've heard that each new term in the series gets 4 or 5 new signigicant digits for your approximation of pi (the more famous euler series can take 100 terms to add one siginficant digit onto your approximation). This means you will still need to caculate probably at least 20000 terms in the series. Even with the crazy savants in the world, you clearly aren't going to be able to work that out in your head. By the time you stopped, you would be having to keep 2 83000 digit numbers in your head at one time while adding them together, AND while plugging new values around i=83000 into that formula. That would be most impressive.

now blow me, i'm a karma whore...

In March 2005, we discovered engineers at the University of Bath working on a machine that can rapid prototype and replicate itself.

Researchers Hod Lipson and Jordan B. Pollack at Brandeis University have coupled inkjet technology and software to autonomously design and fabricate robots without human intervention.

Neil Gershenfeld, director of MIT Center for Bits and Atoms, who runs a one-semester smash-hit class called "How to Make Almost Anything", is determined to produce affordable, replicating personal fabricators by 2025.

And today Hod Lipson has announced the arrival of simple self replicating robots with enormous potential.

Applications

More complex shapes are possible in principle, such as adding grippers, cameras, new sensors etc. to modules. A robot could assemble itself into a new structure to deal with novel events. Also points a way to self-repairing robots.

Nanomachines: Lipson is interested in making these machines at microscale. That could drive major advances in Nanotechnology because huge numbers of robots are needed to manufacture things at a molecular scale. Self-replication is how biology does it.

Implications

Could change the way almost everything is manufactured. Machines that clone themselves are a key factor in the near horizon revolution of digital fabrication.

The movie (accelerated 4X) is eerie to watch. It's easy to imagine a clutter of cubes picking themselves up and walking towards you.

Sorry to bust your bubble here, but steel CANNOT be made molten from burning jet fuel in open air. Also, steel buildings have stood up to much more abuse, and haven't collapsed.

Yes, I'll probably take a karma hit on this one, but this myth has gone on long enough.

The web site is a joke site, obviously.

As to your other question, a flat object can have an infinite edge (perimeter) but finite area if it's a fractal, like a Koch snowflake.

Currently there's one faculty and one undergraduate in the project. So the manpower is rather light. But even so the project appears useful and maybe achievable even with that little manpower. Anyone with experience with this sort of rapid prototyping want to comment? I like the idea of first building a self-replicating machine (presumably with some human labor still required) and then refining it. This seems a good approach to me and it's exciting that we're actually as close as we are to doing this.