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Comment Re:Except they used regular SMS (Score 1) 291

My read on it is they mean the vendor has zero knowledge of how to break the encryption to gain access to a user's data

Oh, the vendor has plenty of knowledge on how to break the encryption - they developed it, after all - it's just that the knowledge of how the encryption works doesn't lead to any feasible way to break it in any reasonable timeframe. The knowledge the vendor has about breaking the encryption is "brute force is your only recourse, and we hope you can wait a loooong time."

Comment Feynmann (Score 4, Insightful) 337

Having no personal experience in choosing textbooks (just buying many of the assigned texts in college - not much choice there), my view on the process is heavily influenced by Richard Feynmann's recounting the time he served on the California Curriculum Commission in Surely You're Joking, Mr. Feynmann. For those who haven't read it before, here's his chapter on Judging Books by Their Covers.

Comment Re:buy our dying batteries (Score 1) 73

Meh, if the pack has a certain nameplate capacity (kWh of storage, kW of output power), then it should not matter much if packs are new or old. The physical size will be different, since you'll need more aged batteries to match the capacity of new batteries. I'd be more interested in seeing the terms of the warranty.

Comment Re:3D Printed Gimbal (Score 2) 15

In other words, the most complicated way yet devised of sending an electrical signal about 10cm.

Perhaps, although this method has some advantages to it:

  1. it does not require invasive retrofitting of the existing wheelchair joystick. As shown in the video, attaching the gimbal requires able-hands only about 10 seconds. I would guess that an attendant would still be able to use that joystick to drive the chair, even with the gimbal attached (although usually for such patients, a second, more easily accessible attendant joystick is part of the controls)
  2. The communications between the joystick (usually called the user control panel, or UCP) and the motor drives on the chair are often CANbus-based, but not always, and the protocol varies by manufacturer. The details of the communications are generally not public, meaning that they'd need to be reverse-engineered for each make and model of chair - which is a tremendous hurdle to development and widespread adoption. The eyedrivomatic avoids these electrical differences. there may still be some manufacturer-specific changes for properly mounting the gimbal on different chairs, but most folks are generally more adept at mechanical hacking than electrical and software.
  3. As one who works on embedded electronics all the time, I can't tell you how gratifying it is to see the workings of the software realized out in meatspace. That is, when the eyedrivomatic is working, you can see it working. Silent and hidden electronic signals provide little indication that they are working, or in what way they are not working.

Considering that the developer is not an engineer by training, and has done most of this on his own, I applaud what he has been able to pull off.

Submission + - Lessons From a Decade of IT Failures - IEEE Spectrum (

mixed_signal writes: IEEE Spectrum has an online set of articles, or "lessons," on why big IT projects have failed, including analysis of the impacts of failed systems and the life cycles of failed projects. From the summary: "To commemorate the last decade’s worth of failures, we organized and analyzed the data we’ve collected. We cannot claim—nor can anyone, really—to have a definitive, comprehensive database of debacles. Instead, from the incidents we have chronicled, we handpicked the most interesting and illustrative examples of big IT systems and projects gone awry and created the five interactives featured here. Each reveals different emerging patterns and lessons. Dive in to see what we’ve found. One big takeaway: While it’s impossible to say whether IT failures are more frequent now than in the past, it does seem that the aggregate consequences are worse."

Comment Re:stationary inductive already exists. (Score 1) 77

One important difference between stationary and in-motion inductive charging is that, well, the car is in motion. This means that every metal component in the vehicle will be passing through a magnetic field (unless they figure how to switch the field on and off only when the receiver is directly over the emitter, and doesn't have much flux leakage). A changing magnetic field in metal creates eddy currents that oppose the change in the field (Lenz's law), which is usually a repulsive effect. This is the basis of an AC induction motor (no permanent magnets involved - just induction). It can also be used as a non-contact braking mechanism (it is used to bleed speed from roller coasters, for instance). Should be great for vehicles!

Comment Re:But contaminating Saturn is ok? (Score 5, Informative) 65

Consider the end scenarios:

1) Cassini crashes into Enceladus. Because it has no atmosphere to speak of and a solid surface, the spacecraft will impact on the ice and make a real mess. Fragments of the spacecraft may survive, more or less in the condition that they left Earth (although much older), including the plutonium RTGs. Eventually, these may work their way through the ice and into the subsurface ocean, contaminating a fairly interesting environment (the ocean-ice interface and the ocean-crust interface).

2) Cassini crashes into Titan. Because there is a significant atmosphere, Cassini will burn up to some extent, but some of it, surely, will survive re-entry, distributed over a large area, and thump into the surface. Due to the thick atmosphere and low gravity, the terminal velocity is quite modest (slower than Earth's), so any bits of Cassini that survive re-entry will have a pretty soft landing. This, too, is contamination of a fairly interesting environment (the surface-atmosphere interface, or in the hydrocarbon lakes).

3) Cassini is intentionally de-orbited into Saturn. Saturn is basically all atmosphere and has no surface to speak of: it'll burn up pretty much all the way down, eventually floating in the deepest parts of the planet that are especially dense enough so that even metals are buoyant. These deep reaches are also really hot, which will at least kill anything still alive or viable on the spacecraft, and probably just melt everything in some extreme chemistry. Compared to permanently scattering the spacecraft across a moon, the amount of time Cassini passes through the various layers of Saturn before reaching its hot death is quite brief. Finally, Saturn is the 2nd most massive planet in the solar system, 10^3 -to- 10^6 times the size of its moons, so any contamination from Cassini will be much more diluted.

So, considering that getting Cassini out of the Saturn system is not possible, tossing it into Saturn itself seems the best option.

Comment Re:US $40K processor (Score 1) 76

My favorite is the "vault" they constructed for the electronics on the Juno mission to Jupiter. Because that mission regularly dips into the radiation belts around the planet, even the best rad-hardened processor would not survive. Over the mission lifetime, it'll have to survive the equivalent of 100 million dental x-rays. NASA's solution: 200 kg of titanium. (Lead would have been too soft to survive launch. Other materials, such as tungsten, are relatively difficult to work with. Titanium is a well-understood.)

More details here.

Comment Re:Slant much? (Score 2) 139

Because The U.S. and Iran just entered into an anti-nuclear agreement, and this detector technology will be important for verifying Iran's compliance. Specifically, verifying that they are not developing a plutonium fuel cycle.

Sure, it can (and probably should) be used elsewhere, but the contemporaneous motivation is Iran. The article makes this clear but, this being slashdot, I guess no one bothered to read it.

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