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David Hubbard
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More useful data points are emerging from the Hanjin bankruptcy:

https://news.ycombinator.com/item?id=12559189

The instant shutdown is caused by executives refusing to prepare a plan -- basically still holding out for a bailout, thinking US TARP behavior is the new normal for "too big to fail" Hanjin. The immediate aftermath:

* It looks like the Korea Development Bank is using Hanjin to dump all of its bad shipping assets, then consolidate all good assets into Hyundai Merchant Marine (HMM) and move forward. The global economy gets to pay for this maneuver. https://www.flexport.com/blog/on-hanjin/

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Jérôme Kasparian writes a surprisingly easy to read, and just plain surprising summary of pulsed terawatt lasers spontaneously creating channels when shone through air.

1. The optical Kerr effect leads to the focusing of most of the energy into multiple tight filaments of light (about 0.1mm wide). This is a spontaneous result of the high power of the light, and is sufficient to keep the beam focused 2 KM away from the source.

2. The filaments route around microscopic obstacles, as long as most of the path of the whole laser beam remains unblocked. High-power lasers pass through clouds, without dumping much energy into the water droplets (or other small particles).

3. Due to the lensing and scattering, the light comes out white even when it was infrared at the source.

4. A "significant part" of the light is reflected backward, but not much light is scattered in other directions.

5. Applications include being able to "scan" the gasses of the atmosphere, or particles in a cloud at a few meters' resolution -- including scanning bacteria or weather-forming cloud droplets. The laser could communicate great distances, trigger lightning strikes (yes!),

Read the article to find out all the details. It's quite fun!
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Microwave ovens are curious beasts. A super convenient method of warming up certain foods, for boiling a cup of water, melting a little butter, or reheating frozen leftovers. But all too often, those frozen leftovers end up scorching in places and rock-hard frozen in others. Is this just random?
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+David Hutchison and I were talking about this the other day, wishing we could visualize the standing wave. I would like to see the pattern in 3D though, and without the turntable rotation!
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The religious commitments of the great scientists are often dismissed as vestiges of more superstitious times. Ian H. Hutchinson offers a window into the intellectual and religious lives of the two greatest nineteenth-century electricians and shows how their religious beliefs facilitated their scientific accomplishments.
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Every combination lock actually has 2 combinations which will open it (because you can dial the combination Right-Left-Right or Left-Right-Left and they aren't on exactly the same numbers)
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Kind of funny, kind of amazing, very worth a read:

As a freshman at college, I pranked my floormates by saying I had an AI running on my linux box (I know it dates me, but back then being a guy running linux was a rarity).

In reality I just had a co-conspirator nearby to respond to my floormates' written prompts.

Well, it's not a prank anymore: http://arstechnica.com/the-multiverse/2016/06/an-ai-wrote-this-movie-and-its-strangely-moving/
For Sunspring</i>'s exclusive debut on Ars, we talked to the filmmakers about collaborating with an AI.
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Freedom to tinker is protected for cars (Magnussen-Moss Warranty At), protected for Free Software, protected for your cell phone (DMCA), but the effort to free FPGAs is being blackballed by the FPGA manufacturers.

Quoting from http://www.megacz.com/thoughts/bitstream.secrecy.html:

Every FPGA vendor keeps the bitstream format for their device secret. Only the tools provided in binary-only format by the vendor (and a select few third parties under NDA) can generate these bitstreams.

Currently, this is a major impediment to the development of an open source FPGA toolchain, as well as to “next generation” FPGA designs involving evolution (http://citeseer.ist.psu.edu/41680.html), self-reconfiguration, peer-reconfiguration, self-placement (http://portal.acm.org/citation.cfm?id=611824) self-routing (http://portal.acm.org/citation.cfm?id=611830), and on-the-fly defect repair.

Arguments for bitstream secrecy (and rebuttals):

1. To protect our customers' designs from reverse engineering

Almost every FPGA vendor offers a device that either loads an encrypted bitstream from off-chip memory (the decryption key is held in tamper-proof memory on the FPGA), or else integrates the configuration memory into the same package as the FPGA.

Moreover, as NeoCad demonstrated (http://www.edn.com/article/CA56710.html), reverse engineering the bitstream itself isn't really that hard. In reality, this is unlikely to be a barrier to a serious reverse-engineering effort.

A Xilinx employee claims that this would be “too expensive” by providing anecdotal evidence about a single unnamed firm he contacted. However, hard empirical evidence shows that this is not true in general.

2. To protect the structure of our chip so our competitors can't mimic it

It's highly dubious that the format of the bitstream would really offer much insight into the physical structure of the device. Even then, there are plenty of overseas companies which specialize in extracting dies and reconstructing a mask image from them.
Ultimately the only real protection against this concern is the Semiconductor Mask Protection Act US Code, Title 17, Chapter 9, which was successfully used for exactly this purpose in Altera v. Clear Logic (http://www.eetimes.com/document.asp?doc_id=1189146). Bitstream secrecy is neither necessary nor sufficient.

3. We'd have to support people doing all sorts of strange things

Of course not. If you fiddle with the microcode on your Pentium chip and go crying to Intel, they're going to laugh at you. FPGA vendors are entitled to the same boundaries.

4. We make money off the tools

Xilinx [by far the largest manufacturer by revenue] says that this is not true. https://web.archive.org/web/20051120135625/http://www.opencollector.org/news/Bitstream/disbelief.html

5. Customers will damage their FPGAs with invalid bitstreams, and blame us for selling unreliable products.

This used to be true when FPGAs had internal tristate resources (so you could drive the same net from competing sources); this is no longer the case for modern devices.
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Here's the best *actual* *data* I could find on the VW Emissions Scandal:

[Quoting from http://arstechnica.co.uk/cars/2015/09/report-vw-was-warned-about-cheating-emissions-in-2007/?comments=1&post=29829701 ]

The initial study leading to unraveling the VW cheat was actually from Europe called "REAL WORLD EXHAUST EMISSIONS FROM MODERN DIESEL CARS" and dated October 2014. One of the four authors was Peter Mock, a German.

15 cars from 6 different brands were tested in real-world conditions for carbon monoxide (CO), total hydrocarbons (THC), nitrogen oxides (NOx) using portable mass spectrometers (PEMS). It seems 2 out of 15 cars were made by VW. In corollary, the authors state that "that modern diesel passenger cars have low on-road emissions of carbon monoxide (CO) and total hydrocarbons (THC), but an unsatisfactory real-world emission profile of nitrogen oxides (NOX)." It states further "This report presents strong evidence of a real-world NOx compliance issue for recent technology diesel passenger cars, both for the EU and US test vehicles. The high temporal and spatial resolution of PEMS datasets was used to link the elevated NOx mass emission rates to the driving conditions that cause them. It was found that a sizable share of NOx emissions over individual test trips (typically lasting about one hour) were concentrated over a number of discrete emission spikes spanning a few seconds. These emission events, which varied in frequency from vehicle to vehicle, could not be attributed to "extreme" or "untypical" driving in most cases. Instead, they were due to transient increases in engine load that constitute real-world driving (e.g., uphill driving, acceleration on a ramp, or positive accelerations from a standstill), or to regeneration events that are part of the normal operation of diesel exhaust aftertreatment systems. The average, on-road emission levels of NOX were estimated at 7 times the certified emission limit for Euro 6 vehicles."

There are 3 main technologies for NOx aftertreatment: LNT (lean NOx traps), selective catalytic reduction (SCR using urea tanks) and exhaust gas regulation (EGR). LNT or SCR can be combined with EGR for improved detoxification.
Brands and types were not disclosed, cars were rather named A-O. However, from a recent interview in "Der Spiegel" with Peter Mock one can conclude that car L was a VW-Passat with SCR and car H was a VW-Jetta with LNT. [The BMW X5 are vehicles A -- EU model -- and B -- US model. F may be a US-model VW Jetta and D, E, and G may be EU VW Jettas.] These two cars showed NOx emissions of 1783 and 1809 mg/km, resp. Only one car, vehicle C, scored below Euro-6 limit (80mg/km). If one takes out H and L, average NOx emissions of 13 cars from 5 presumably non-VW brands was 430mg/km (>5-times Euro-6 limit). So this is not a Volkswagen-alone problem.

The study can be downloaded from http://www.theicct.org/sites/default/files/publications/ICCT_PEMS-study_diesel-cars_20141013.pdf

With respect to overall NOx poisoning contributed by Volkswagen: In the EU about 40% of NOx emissions come from car traffic, about 50% from power plants, industry, households and commercials. This most likely is similar in the US. VW has a market share of 2% in the US, not all diesel. Now do the arithmetics on your own. They cheated. They should be and will be bitterly fined. But things should remain in proportion.


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The WVU findings are included in the ICCT findings. Actual results are not expected to be below the test limit. There is no diesel car that actually produces 0.08g/km in real world use. The EU also does not expect any car to produce 0.08g/km in real world use. That's the whole point of all of this.

The assumption about how much more these cars emit in the real world has been wrong. VW has an engine that is one of the worst offenders of the 15 tested engines, but it is not 10 times worse, let alone 40 times worse, than the other engines evaluated. It is about 7 times worse than the test standard.
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I'm happy that a large company (in this case, Lenovo) has said they didn't do enough. It's not exactly a "mea culpa" but the honesty is refreshing.
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I've gotten a chance to test out this new crypto device: http://www.computer.org/cms/Computer.org/ComputingNow/pdfs/AuthenticationAtScale.pdf

I like it! This could be useful for a lot of 2-factor logins like at a bank.
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I know a very talented engineer at Sierra Nevada Corp that just got laid off (the NASA contract went to SpaceX and Boeing). Anybody at SpaceX or Boeing hiring right now?
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Thanks! Passed on their jobs listing...hope it works out for him.
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Even MLB (Major League Baseball) opposes Comcast and Time Warner's attempt to introduce "Internet Fast Lanes." Maybe I'll buy MLB season tickets for the first time in, well, forever.
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