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The answer, according to this solar energy MOOC, is a resounding yes: the panels produce much more energy than they took to build.

“Traditional single-processor pathnding strategies, such as A* and its derivatives, have been long praised for their exibility. We implemented several parallel versions of such algorithms to analyze their intrinsic behavior, concluding that they have a large overhead, yield far from optimal paths, do not scale up to many cores or are cache unfriendly. In this article, we propose Parallel Ripple Search, a novel parallel pathnding algorithm that largely solves these limitations.”
http://graphics.tudelft.nl/~ra...
I disagree with your basic assumptions.

The foreign countries might already have similar tech, maybe even years ago:
http://www.rslab.ru/downloads/...
http://ieeexplore.ieee.org/xpl...
http://repository.tudelft.nl/a...
https://encrypted.google.com/b...

One of the early Gopher/FTP sites was at tudelft and was called the Digital Archive on the 17th Floor (List of websites founded before 1995). This small image archive contained some low quality scanned pornographic images that were initially available to anyone anonymously, but the site soon became restricted to Netherlands only access.

Unfortunately the link is dead. And even searching for the archive using archive.org database, the earliest I could find was December 2, 1998. The porn was already deleted.
If anyone saved that picture archive, please notice that what you have is data is a landmark in human history(Just like that Playboy picture used in computer graphics). Quoting Dr. Jones: This archive belongs in a museum!

I just read about someone who did his dissertation on elevator dispatching algorithms here. The full dissertation is here: Heuristics in dynamic scheduling: a practical framework with a case study in elevator dispatching.

I mean, what could possibly go wrong?

The TU in Delft, the Netherlands has a nice toy for students as well. At 2 MW(th) and with an imminent upgrade to 3 MW(th) it's not a small one either.

I believe it uses the Mach microkernel, and therfore can be ported quite quickly

At this point, XNU probably isn't significantly easier to port to another architecture than, say, the Linux kernel or one of the *BSD kernels or the SunOS 5.x kernel. (And, in any case, XNU's already been ported to ARM, as have the other userland bits of Darwin; that's what iOS is built atop. What he did was port the ARM version of Darwin to a new piece of hardware - one that had an ARMv5 processor, which required, among other things, cleaning up some bitrot in the ARMv5 support. Read The Fine Thesis.)

No, that was not a troll - the A4/A5 chips are based upon ARM chips

What the heck is an "ARM chip"? ARM is fabless, so it's not a "chip that ARM fabbed". If it's a chip whose main processor runs the ARM instruction set architecture, then the A4/A5 are "ARM chip"s.

but have been modified to suit Apple's needs

ARM is in the "intellectual property" business; all sorts of vendors put ARM cores into various systems-on-a-chip - the A4 and A5 are hardly unique in that regard.

The ARM support in Darwin is pretty much common to all ARM cores (although, as the thesis noted, the ARMv5 support had bitrotted a bit). There's also probably core-specific and system-on-a-chip-specific stuff in there, but that stuff is probably different between the various non-A4/A5 chips used in the older iOS machines, so it's not as if A4/A5 are Some Unique New Thing distinct from Boring Old ARM.

What I took from the article was that Apple would be taking a brand new ARM chip

What I took from the thesis (rather than from an article written by somebody who may not have understood what the guy was saying in the thesis) is that Apple would be taking the MV88F6281 ARM chip from Marvell - which is hardly new as it dates back to at least 2008 (in the References section of the thesis it cites Marvell's "8F6281 Hardware Specifications document" and gives a publication date of December 1, 2008) - and doing something on it (not entirely surprisingly, the thesis says nothing whatsoever about what that "something" might be). As the thesis says:

The goal of this project is to get Darwin into a workable state on the MV88F6281 processor so that other teams can continue their work on this platform.

and then using it to drive Mac OS.

The thesis, other than having "ARMing the SnowLeopard" as its subtitle and making the incomplete statement that "Darwin is the lower half of the Mac OSX operating system" (it is, but it's also the lower half of the iOS operating system), doesn't say much about porting "Mac OS". In fact, he repeatedly speaks of "embedded" platforms

You would then have three unique Apple architectures to develop for - iOS, Intel-based Mac OS, and ARM-based Mac OS.

Which has to do with two separate things - instruction-set differences and OS platform differences (iOS vs. Mac OS X).

And considering an intern could port a complete OS port in a mere 12 weeks, shows how portable it is.

Yup, and one of the bits of portability that helped was that it had already been ported to ARM. To quote The Fine Thesis:

When I began this project, development for the MV88F6281 was being done with a train from a different ARM based project. This made sense, because both projects are ARM based, and thus share a lot of code, libraries and low-level platform support.

so he was using the existing ARM support in Darwin. The problem is that the code in question didn't work on the MV88F6281 for a variety of reasons, including bitrot in the ARMv5 support, and that's what he had to deal with.

And indeed I recall rumours that OS-X was running on Intel from before the time the rumours came that Apple was planning to switch to Intel.

Yes, it was. (That's the "secret double life" to which Jobs referred in the MacIntel announcement.)

I suppose portability is simply part of the demands by management. I don't think Microsoft will have such an easy time if they were ever to switch to another architecture.

Yeah, it'll probably be hard to port an OS core that was originally developed on the Intel i860 and moved to MIPS, to make sure x86isms didn't creep in; admittedly, perhaps after the non-x86 versions were killed off, one by one, more such stuff crept in, but perhaps the OS core has been running on ARM for a while "just in case". However, the stuff above it might have more x86isms in it.

So he spent 12 weeks porting a kernel that had already been ported 3 years ago?

Porting it to a development system that had a processor with an older version of the ARM architecture support for which had bit-rotted.

iOS and Mac OS X are already the same kernel.

And much of the same lower-level userland.

Of is the real story that he was back porting lion advancements to the iOS version.

Where was that mentioned in his thesis?

Please read this OS News article, which explains why this does not mean "Mac OS X was ported to ARM", and the actual thesis before commenting.

tl;dr version of the OS News article - it's just a port of Darwin, using the existing ARM support, to an ARMv5 platform, that included fixing bitrot in the ARMv5 support.

One undergraduate spending 12 weeks porting Darwin (!) to a new CPU architecture

And it's not really very "new" - the architecture in question is ARMv5, and there already exists a port to newer versions of the ARM architecture (it's in these little-known things called "iPhones" and "iPads" and "iPod touches" and "second-generation Apple TVs"), so a lot of what he had to do, as indicated in The Fine Intern Thesis, was deal with bitrot in ARMv5 support (perhaps some early work on what is currently called iOS involved ARMv5 development platforms, but I don't think any of the machines that ship with iOS have ARMv5 processors in them).

TFA says he ported Darwin - the open-source version of the OS X kernel

Kernel and core bits of userland, actually.

What's more, what he ported was the (not-completely-open-source) ARM version of Darwin (little if any of ARM support is open-source), which already exists - it lives, for example, in every one of those mobile phones with the apple-with-a-bite-out-of-it logo on the back, for example - and what he ported it to was an ARMv5 platform, and a lot of difficulties were due to bitrot in the ARMv5 support, as stated in The Fine Intern Thesis

So, as you say, this says little about porting Mac OS X to ARM.

(If I could post in this thread and moderate your posting up by 10^10^100, in the hopes that everybody who thinks this means "OMG APPLE'S BUSY PORTING MAC OS X TO ARM!!!!!111ONE!!!!!!", I would. Most of the discussion that this report has engendered all over the Intarwebs is a real case of "teh stoopid, it burns!")

You have to click through a lot of links to get there, but the PDF of his dissertation is online at his university's website: http://repository.tudelft.nl/assets/uuid:2f66fe0c-4080-4148-a01c-acd530160797/Report_BSc_complete.pdf

First, try googling "bicycle castor". You will find that the unfortunate clause in the Wikipedia article you cite is the only reference on the internet that equates caster with trail. The word "caster" when used with regard to vehicle suspensions refers to an angle, not a linear measurement. The confusion probably arose due to the fact that castor angle can be inferred from rake, trail, and wheel size, which are all linear measurements.

Trail is a guideline used by bicycle designers. It is neither necessary nor sufficient for stability: The authors of the Science article (sources and preprint here) built a stable negative-trail "bicycle"; and they show that the eigenvalues for conventional bicycles are unstable above a critical speed. However, the suggestion that trail - the largest force affecting steering - is irrelevant to the stability of conventional bicycles is ludicrous. You can do the math and calculate eigenvalues as you alter trail, or simply ride a bike equipped with an adjustable trail for to see this for yourself.

To quote Jim Papadopoulos, "perhaps the main message is that our reasoning about how trail affects bicycle stability has been quite wrong for 120 years". This is not a denial that trail affects stability, but rather a search for a better model. Unfortunately, that better model has not yet yielded any insights of use to the designers of actual ridden bicycles.

The Delft University of Technology has a good name, partly due to the fact that a lot of students started their businesses with their graduation projects. They have the profit they need (a good name) and the students have the profit they need (a good idea for their company). The Senz storm umbrella started that way.

The abundance of calls to emergency lines during crises is dicult to handle by the limited number of operators. Detecting if the caller is experiencing some extreme emotions can be a solution for distinguishing the more urgent calls. Apart from these and there are several other applications that can benet from awareness of the emotional state of the speaker. This paper describes the design of a system for selecting the calls that appear to be urgent and based on emotion detection. The system is trained using a database of spontaneous emotional speech from a call-centre. Four machine learning techniques are applied and based on either prosodic or spectral features and resulting in individual detectors. As a last stage and we investigate the eect of fusing these detectors into a single detection system. We observe an improvement in the Equal Error Rate (eer) from 19.0 % on average for 4 individual detectors to 4.2 % when fused using linear logistic regression. All experiments are performed in a speaker independent cross-validation framework.

Taken from here. The International Journal of Intelligent Defence Support Systems web site doesn't appear to be updated with this year's 2nd volume yet. [The English is a bit clunky, but the researchers appear to be Dutch so I forgive them that, at least.]

Tribbler is also Open Source so the government cant shut it down

Tribler was developed (and is still maintained IIRC) by a research group at Delft University of Technology led by Johan Pouwelse. He has also appeared as an expert witness in several (at least one) US filesharing cases. As long as the UT continues his funding (right now he's being funded by the EU as well) I don't see Tribler being shut down any time soon.

That said, he is quite outspoken on his views on traditional media (distribution), so I wouldn't be surprised if at some point the UT will get pressured to release/reassign him. Then again, he has tenure...

Modern x86 gives you 16 integer registers

But not on IA32, which this Atom will be running (desktop Atoms support it, but it will be disabled here). In addition using AMD64 means longer instruction prefixes, negating your "really compact" argument. Of course when smartphones are coming with 512MB RAM (Nexus One), is code compactness really an issue any more?

Thumb2 negates the limitations of Thumb1, giving full access to registers and operations. And it has decent code compactness on top, although I don't know how it compares with x86 - maybe there are some comparisons out there? http://iccd.et.tudelft.nl/2009/proceedings/459Weaver.pdf has some interesting data but neglects to include Thumb.

In the end, ARM is dominant in the mobile and smartphone arena, and backwards compatibility with x86 isn't a concern. Looking at the size of this "phone" it'll require another generation of integration to get x86 competitive in terms of implementation area. In the meantime an 800MHz Atom is going to compare very badly with dual-core >1GHz A9s.

Yes, there have been compilations of such examples... why indeed is this news?

Nothing to see here, move along...

I don't think I've ever seen a more undeserved insightful mod. That was non-specific heckling without a point.

Here are some points for you: the amount of innovation in green energy is tremendous these days. Take your pick, some of these are from this very site:

24/7 baseload electricity from the sun for utilities, great for sunny climates, cost-competitive with coal
Steady large-scale wind power from stacked kites
Cutting consumption and greenhouse gasses with microgrids
As seen on this very site, cost-effective solar thermal energy used to drive a stirling engine
Highly cost-effective thin-film solar electricity
Solar thermal panels for directly heating water
For efficiency, passive solar design for buildings
Inserting vertical wind turbines into electric towers for using existing structure
Tidal energy, pros and cons; Denmark certainly believes in the pros

That's just off the top of my head. Renewable energy is a matter of studying your surroundings and finding what is appropriate. Each locale is different, and of course, all of us can benefit from more efficient design than what we used on this past century while presuming that fossil fuel energy is cheap and disposable. All we need to do is stop being sloppy and wasteful. ...Or you can just be pointlessly negative on the internet. :)

Ok, done in black and white:
http://www.etv.tudelft.nl/vereeniging/archief/lustrum/90/
Select "Tetris Record" from the menu. It's still nice to see those projects.

Allow me to add a few, since I might know a thing or two about this subject. Some of you might remember Flame, a robot designed at the TU Delft, and being used to further understand human walking (he walks like we do, as opposed to for example Asimo...)

http://www.3me.tudelft.nl/live/pagina.jsp?id=c4fa06f1-b767-4a67-a19e-ea3356400f06&lang=en

The nice people at DBL (Delft Biorobotics Laboratory) have built a next generation robot called TUlip

http://www.dutchrobotics.net
for those interested. That's one I worked on a little, so I might be a little biased in terms of how cool it is :-)

Some more cool robots we saw in China and elsewhere are:

The Cornell Ranger's record for longest distance walked
http://ruina.tam.cornell.edu/research/topics/locomotion_and_robotics/papers/CornellRanger/index.html

or maybe nexi?

http://robotic.media.mit.edu/projects/robots/mds/overview/overview.html

Or take your pick from a variety in this list:
http://www.ri.cmu.edu/research_project_view.html?menu_id=261

or this one

http://www.rec.ri.cmu.edu/project/index.htm

Plugging myself (again): I wrote a small research article about heterogeneous architectures which proves there is a method to determine which part of the job requires fast processing (either raw speed or functional optimalization by the processor). It required the job to be partitioned (to Kahn process networks) and profiled but you can think of more dynamic optimalisations.

By the way: priority is not a term to use. Its premise is that there is a shortage of processors to schedule on. If you have a heterogenenous environment with a lot of processors, you never have a shortage (just a lot of bad choices to make).

Arguments for or against windmills just aren't the last word on wind powe r. The laddermill, kite generator, and wind belts previous mentioned here all present potential for different situations.

I think a diversified portfolio of renewable energy and superconductor research is the way to go.

http://ch.tudelft.nl/~arthur/rl/
From the webpage: rl is a command-line tool that reads lines from an input file or stdin, randomizes the lines and outputs a specified number of lines. It does this with only a single pass over the input while trying to use as little memory as possible.
Didn't know about it either. Seems marginally useful

"perhaps the use of robots like this would be more appropriate: http://www.tudelft.nl/live/pagina.jsp?id=1468ded9-96cb-47dd-aed3-da0a70a34813&lang=nl"

Well, that's an easy one to demolish...

Many caves have serious air flow, so where is this toy going to get a lightweight motor and batteries powerful enough to make any headway into/out of the cave?

It's not, it's a research "toy".

Wheres the navigation system on it?

Can't use radio since it basically doesn't work inside caves, so it needs an autonomous navigation system.

Wheres the camera/s?

Wheres the recorder to save the data?

You all can't seem to grasp the amounts of energy needed to navigate a cave system by humans or robots.

Thanks for playing though.

There is an assortment of additional video links on this page

http://www.tudelft.nl/live/pagina.jsp?id=1468ded9-96cb-47dd-aed3-da0a70a34813&lang=en

Its like they are catering for everyone, because each link has a different format.

You might be interested in the Delft Method, which was created specifically for engineers, to learn a language very very quickly and efficiently.

well I guess you are right about it being an intermedeate stage. I guess that things are going to go the cell way from now on, but with a different abstraction level visible to the guys programming it, I think the TRIPS architecture http://en.wikipedia.org/wiki/TRIPS_architecture that IBM has or the Mollen architecture http://ce.et.tudelft.nl/publicationfiles/908_9_prototype_molen.pdf might be the future.

As I demonstrated in my thesis a parallel application can be shown to have certain critical and less critical parts. An optimal processing platform matches those requirements. The remainder of the platform will remain idle and burn away power for nothing. One should wonder what is better: a 2 GHz processor or 2x 1 GHz processors. My opinion is that, if it has no impact on performance, the latter is better.

There is an advantage to a symmetrical platform: you cannot misschedule your processes. It does not matter which processor takes a certain job. On a heterogeneous system you can make serious errors: scheduling your video process on your communications processor will not be efficient. Not only is the video slow, the communications process has to wait a long time (impacting comm. performance).

Ship propulsion by Kites combining energy production by Laddermill principle and direct kite propulsion (PDF!)

Instead of wind mills, we could get more power for more time by taking things to the sky. E.g. the "Laddermill":

http://www.lr.tudelft.nl/live/pagina.jsp?id=8d16d19a-e942-45aa-9b52-48deb9312e92&lang=en

They are certainly not the only ones doing pioneering work in this field:

Laddermill from the Technical University of Delft is also working on it for a number of years now:
http://www.lr.tudelft.nl/live/pagina.jsp?id=8d16d19a-e942-45aa-9b52-48deb9312e92&lang=en

Publications:
http://www.tudelft.nl/live/pagina.jsp?id=fe263f84-29af-4010-8222-2f1112c8f223&lang=en

The more alternatives for environmentally friendly energy sources the better! :)

They are certainly not the only ones doing pioneering work in this field:

Laddermill from the Technical University of Delft is also working on it for a number of years now:
http://www.lr.tudelft.nl/live/pagina.jsp?id=8d16d19a-e942-45aa-9b52-48deb9312e92&lang=en

Publications:
http://www.tudelft.nl/live/pagina.jsp?id=fe263f84-29af-4010-8222-2f1112c8f223&lang=en

The more alternatives for environmentally friendly energy sources the better! :)

Actually Delft is a city (though not that big). Delft University is quite renown for its technical innovations, such as the Nuna Car series (and winning the Solar challenge 3 times in a row if I remember correctly.

Right, let me begin by saying that after reading ftp://ftp.cs.utexas.edu/pub/dburger/papers/IEEECOM PUTER04_trips.pdf it actually became a bit more clear about what they were talking about.

It might sound very novel if you are only accustomed to normal processors. Look at MOVE http://www.everything2.com/index.pl?node_id=103228 8&lastnode_id=0 to see what transport-triggered architectures are about. They are more power efficient, etc etc.

Secondly, they talk about how execution graphs are mapped onto their processing grid. I don't think any scheduler has a problem with scheduling an execution graph (or whatever name you give it) to an architecture. Generally, it can be scheduled in-time (there is a critical path somewhere) or it is scheduled with a certain degree (generally > .9 efficient) of optimality. I don't see the gain there in efficiency.

Now here comes the shameless self-plug. If you want to gain efficiency in scheduling a node of an execution graph you have to know which node is more critical than the other. The critical nodes (the ones on the critical path) need to be scheduled to the fast/optimized processing units and the others can be scheduled to slow/efficient processing units (and they can get some communication delays without penalty). Look http://ce.et.tudelft.nl/publicationfiles/786_11_dh ofstee_v1.0_18july2003_eindverslag.pdf here for my thesis.

If they're going to make it so big the least those billy goats could do is use 2xSaI. *sigh*

They did win the 3 last World Solar Challenges and recently a Solar boat race. I guess they think the battery capacity of 5 kWh allowed in the challenges asks for lighter batteries. They have been underestimated before

http://nl.wikipedia.org/wiki/World_Solar_Challenge

http://www.3me.tudelft.nl/live/pagina.jsp?id=74ad0 ef5-3e51-4029-b42b-62011e2b11e0&lang=nl

Ernst

http://www.rrr.tudelft.nl/live/pagina.jsp?id=d5ee3 fb5-22d1-4a38-a626-95255dd0c479&lang=en gives a list of publications about their research on Li-Ion technology, including PDF files in english

http://www.tudelft.nl/live/pagina.jsp?id=40a4cfdf- 683e-4db7-9675-c5c57399329c&la

      I saw that link and at first thought, "Pah-jy-nah? WTF?" Then I realized it was Spanish. "Oh, pah-hee-nah! That explains it!"

Insert snide male chauvinist remarks here. For extra points mention plastic and conductivity.
By the way, she's not bad looking at all, picture (and phone number!) here: http://www.tudelft.nl/live/pagina.jsp?id=40a4cfdf- 683e-4db7-9675-c5c57399329c&la

See their website at http://mms.tudelft.nl/dbl/research/biped/

-FL

-FL

-FL

-FL

Another record, from Adelaide to Darwin (3000km) is held by the dutch solar car Nuna 3, which averaged 103km/h. This would have been higher if not for speed limits on the Australian roads. The speed record for solar cars (without any imposed limits) on normal roads has been more or less maxed out.

The Delft University of Technology will be participating in this race with the Nuna 4. This is the team - also a student team! - that won the race in 2001, 2003 and 2005. There's a brief explanation of the new rules on their site:

New this year for the competition class are regulations requiring a full motor vehicle specification lighting package, a normal seating angle for the driver, and a scaling back of the maximum solar panel area from 8.9 square meters to 6 square meters. Saftey concerns have also prompted the regulators to require a roll bar in the vehicle, and an exterior body that can handle four times the weight of the vehicle itself.

The Faculty of Aerospace Engineering, which has been a major force in getting and keeping this project going, meanwhile has found an even higher goal for the next student project: the design of a Blended Wing Body Aircraft. If the success with their solar power car is anything to go by, we will see some serious innovation in aircraft design in the time to come.

http://www.etv.tudelft.nl/vereeniging/archief/lust rum/90/english.html was the Guiness book of records attempt by the faculty of Electrical Engineering at Delft University of Technology in the Netherlands.

I was there and it was absolutely hilarious :) Although walking through the corridors was a slight bit of a problem with all the cables lying there.

Great stuff for those interested in Tetris :)