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Comment Re:I say BS (Score 2) 109


And I'm telling you that lithium-ion batteries are not a "single tech", that they've dramatically improved in power and energy density (both volumetric and gravimetric) over time. And if you doubt this, I repeat: go find and older lithium-ion battery and compare it to a new one.

As for li-air, yes, the maximum energy density of li-air is about 10x of the maximum of li-ion. Namely because it works by direct oxidation rather than intercalation, so you don't need the mass of the matrix into which the ions get intercalated. It is not a "magical tech". It exists. Like all technologies in all fields, however, you have to reach production specs. This means not only maintaining a combination of safety, reliability, longevity, efficiency, temperature range, power density (charge and discharge) and energy density, but also affordability in mass production. And to be able to guarantee that you can do all of these things to a high enough level for investors to take the risk.

As with all technologies, you start out with promise in one or two fields, but serious problems in many others that you have to deal with. With time you refine them, until all of refined to a state where the product is commercialized. Li-air has actually been advancing quite well. In the early days one of its biggest problems were efficiency and longevity, but they've made huge strides in both in recent years. Lithium sulfur still looks nearer term, but commercialization of Li-air appears to have gone from "possible" to "quite probable".

Comment Re:It was a premises warrant. (Score 1) 361

He may in some cases be forced to surrender a key to a strongbox containing incriminating documents, but I do not believe he can be compelled to reveal the combination to his wall safe —- by word or deed

Meaning the fingerprint gathering for the use of opening the phone is tantamount to compelled testimony in the general case, while the fingerprint gathering for the use of identification and matching is not.

Keys don't change. Fingerprints don't change. A biometric identifier is therefore not affirmative.

Combinations can change. Pin codes can change. Utilizing either requires active participation in a process. And is therefore affirmative.

Fingerprint usage is therefore tantamount to using a key, and if you are stupid enough to use a biometric identifier as an access method, you've picked a non-affirmative access method.

Comment Re:Halfway There (Score 2) 373

Right. Out of the 330 million people in the US (not counting the broader market, there's "nobody" who wants a gun that can't be accidentally picked up and used by their young children or an intruder. Literally "nobody". Yeah, totally believe you.

They have a niche. You want to prevent them from filling it.

Comment Re:Progress! (Score 4, Interesting) 109

Actually, that is a concern. Li-ion batteries don't have lithium metal in them unless something goes wrong. Lithium-air batteries always have lithium metal in them, by design.

In practice, you'll probably see a bit of the energy density given up in order to beef up the casing to prevent rupture/fire.

Thankfully, lithium-sulfur batteries don't use lithium metal, just lithium polysulfides. The max energy density isn't as high, but it's still quite good. They're already on the market, albeit in small quantities for applications that require the absolute highest rechargeable energy density (mainly aerospace).

Comment Re:I say BS (Score 2) 109

Yes, cue the standard "Batteries haven't advanced!" stuff from people carrying around cell phones with significantly more amp hours in a smaller battery profile than the last generation phones that they owned.

News flash: every time a new tech advance makes it into a product, they don't mail a letter about it to everybody who read an article about it years earlier. Example: hey, remember all of that stuff about breakthroughs in silicon anodes several years back? Yeah, they're in batteries now. Even Tesla is starting to use it in their higher-end packs.

Comment Re:67% is not that good (Score 2) 118

It's good for the NAO. When you're pushing the boundaries, anything over 50% is good.

For long-term climate models, things like the NAO average out across many years. For short-term weather forecasting, you have a week or more before the system diverges enough to cease to be useful. But it's tougher working on those in-between scales.

Comment Re:No it can't (Score 1) 118

Should be well worth it in terms of things like planning for agricultural products, natural gas supplies, etc.

The real issue however is that they've validated it with hindcasting. Which is certainly something, but isn't as ideal as you'd want. It's trivially easy to fit any arbitrary past dataset to a statistical model if you have enough parameters that can be tweaked, but that doesn't mean that you're actually capturing the underlying dynamics. That said, from the sound of it it's built around a physical model, so that increases the odds that it actually is, rather than just fitting to some arbitrary curve.

Comment where will it end? (Score 1) 74

I won't dream of a single (or multiple) damn quantum thing until I see an equation that describes a real-world superposition scaling limit, species type "immovable object".

I believed in Moore's law because it was on a collision course with the atom, right from day one. Even as a child, I didn't believe in a Laplacian universe, in the sense that the accumulated knowledge required to compute the deterministic outcome could exist in one place—a place smaller than the universe itself—for any value of "smaller" my small mind was capable of entertaining.

I've been reading articles about quantum computing seemingly for decades now, and not a single article has pointed out any practical scaling limit. For all these dunderheads seem to know, we could cajole the entire universe into a state of Laplacian superposition, if only we didn't suck at stacking these tiny little Lego blocks.

No scaling boundary equation widely promulgated = no credibility widely disseminated = very little fantasy action for people who don't believe in giant green men with anger management issues.

Comment Heh, haven't heard that name in a while. (Score 1, Interesting) 164

I used to follow some of what The Jester wrote. There are a number of people out there who think he's overrated, more brag than anything else. Still, I saw some pretty clever things out of him. For example, at one point he was going after some other hacking collective (I don't recall which one), and he announced a successful attack against them and posted a list of all of their names and real IP addresses. Only, the list wasn't real. Instead, anyone who tried to download the list had their connection logged and probed, an exploit used to trigger the computer to make a (real) TCP connection back to one of his computers, and a number of automated attacks launched against targets it considered particularly suspect (for example, if there was evidence of being logged into a known member twitter account). I.e., it wasn't actually a list of suspects, it was bait to build a list of suspects. I think he did the same trick with QR codes later.

Comment It was a premises warrant. (Score 5, Informative) 361

In a premises search, they can compel an unlock of phones by fingerprint, assuming you lock your phone that way.

The specific legal decision was the 1988 John DOE, Petitioner v. UNITED STATES. 487 U.S. 201 (108 S.Ct. 2341, 101 L.Ed.2d 184) decision.

It came down to whether on not an affirmative action was required on the part of someone, or if it was a non-affirmative action. Use of a key on a safe or lockbox is not affirmative. Being forced to enter the combination is not affirmative; it's tantamount to compelled testimony.

Here's the part of the decision of interest:

A defendant can be compelled to produce material evidence that is incriminating. Fingerprints, blood samples, voice exemplars, handwriting specimens, or other items of physical evidence may be extracted from a defendant against his will. But can he be compelled to use his mind to assist the prosecution in convicting him of a crime? I think not. He may in some cases be forced to surrender a key to a strongbox containing incriminating documents, but I do not believe he can be compelled to reveal the combination to his wall safe —- by word or deed.

Moral of this story: use a pin code, rather than using the fingerprint unlock. It may be a cool feature, but it offers you no legal protection.

Comment Re:Scientists have proven (Score 5, Insightful) 317

To date, the Clinton campaign has not once attacked the veracity of the emails.

Not. Even. Once.

They have bobbed, weaved, prevaricated, projected, and otherwise produced non-sequitur "answers" to the questions about the content. But not once have they said "well, that one there, that's false, we never said that." Instead we get tall tales of Russians hacking the DNC -with no evidence - just the Clinton campaign's say-so.

All attacks are upon the messenger(s) and not the facts. And it's amazing how these emails match up with reality.

That tells me a lot. It tells me that the emails are real, and that once Hillary assumes office, the heat is not going to be off. [grumpy cat]Good[/grumpy cat].

Karma is a bitch.


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