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MIT' Combines Carbon Foam and Graphite Flakes For Efficient Solar Steam Generati 96

Posted by timothy
from the science-fiction-future-awaits dept.
rtoz (2530056) writes Researchers at MIT have developed a new spongelike material structure which can use 85% of incoming solar energy for converting water into steam. This spongelike structure has a layer of graphite flakes and an underlying carbon foam. This structure has many small pores. It can float on the water, and it will act as an insulator for preventing heat from escaping to the underlying liquid. As sunlight hits the structure, it creates a hotspot in the graphite layer, generating a pressure gradient that draws water up through the carbon foam. As water seeps into the graphite layer, the heat concentrated in the graphite turns the water into steam. This structure works much like a sponge. It is a significant improvement over recent approaches to solar-powered steam generation. And, this setup loses very little heat in the process, and can produce steam at relatively low solar intensity. If scaled up, this setup will not require complex, costly systems to highly concentrate sunlight.

Comment: Re:both? (Score 1) 77

by slimjim8094 (#47494179) Attached to: Drone Search and Rescue Operation Wins Fight Against FAA

Um... this is exactly how pilot licensing works - same aircraft, same actions, difference is money? Bam, you need a commercial pilot certificate, a private pilot certificate won't do. Commercial operators are held to a higher safety standard, which makes sense - money brings with it a set of pressures and constraints that your average weekend pilot doesn't have, so their skills should be better.

Would you prefer the FAA require certification of all drone operators, commercial or not? Because they'll do that before they allow commercial usage of drones without at least some oversight.

Comment: Re:And all because a copyright expired! (Score 1) 126

by StefanJ (#47492471) Attached to: Dungeons & Dragons' Influence and Legacy

Sirnomad99 notes that there were other influences. Jon Peterson, author of the scholarly gaming history Playing at the World, suggests that Tolkein and LOTR was just one influence among many. The Conan stories, Pratt and de Camp, Leiber and Vance are all specifically mentioned.

In fact . . . I just picked up the book and turned to page (117) where I'd last left off. There are quotes from Gygax where he suggests that Tolkein is not the be-all and end-all authority on the nature of fantasy creatures.

Oh . . . I actually have a set of the Ace paperbacks! They're not impressive. The special characters look hand-sketched, and the cover art is mediocre.

Comment: Re:Not a rule (Score 1) 199

You're misreading the regulations. Over a sparsely populated area there is no altitude restriction, there's a distance to "person, vessel, vehicle, or structure" requirement. You can fly as low as you want over e.g., a cornfield (say, for crop dusting) or the desert or ocean so long as you don't compromise the "emergency landing without undue hazard" rule. I'd argue that it's not reasonable to expect everyone who buys a drone to become intimately familiar with 14 CFR 91's requirements, so some general rules are warranted. For instance: what if someone wants to operate a drone within a Class E surface area (which is within several miles of many airports, and explicitly goes all the way to the ground because it's for the purposes of taking off or landing) - should they be subject to visibility and cloud clearance requirements? The reason they exist is because instrument traffic coming in to land may be coming out of the clouds and VFR traffic needs to stay clear enough to see-and-avoid them. Seems fairly reasonable, right? But a drone might be below 500 feet and still kill someone if they don't follow these rules.

But that's not really the point. Something makes an aircraft subject to these regulations, right? You can't just get a plane and say you're not an airplane and as long as you fly it below "navigable airspace" you're fine - in fact that's the exact opposite of the rules. The FAA certainly doesn't assert authority over hovercraft or other "ground effect vehicles" - it seems reasonable to assume that the FAA considers its authority over aircraft to begin when they can and/or are designed to be flown into the "navigable airspace". Many drones can fly over 500 feet just fine. I suspect the FAA would be less concerned about a drone with a GPS map magically kept up to date that prevented it from flying into any airport's approach path, and kept it below the minimum altitude for manned flight (including refusing to take off from a field or other "sparsely populated area").

I think the regulation just hasn't caught up with drones, but they're working on it. It won't be the free-for-all some people want it to be, but the FAA isn't some antagonistic supervillain of a government agency. They just want to make sure these things don't get sucked into someone's jet engine or going through a windshield, and they also don't want commercial operations without a higher standard of safety. I'm a private pilot and there's all sorts of rules about money changing hands in regards to my flight, and while it's occasionally obnoxious the intent to prevent a bunch of "Billy Bob's Charter" services from popping up everywhere. If you're in a manned aircraft and you want to be compensated for flight, you need to be a commercial pilot, which has higher standards. I don't see why the same basic principle of having higher standards shouldn't apply to commercial drone operations - and neither does the FAA, which is why they're going through the rulemaking process as we speak.

Comment: Re:Not a rule (Score 1) 199

Go nuts. Their policy notice (basically "we interpret the already-existing regulations in this way") was struck down as insufficiently supported, so they're going through the official rulemaking process to make an actual regulation out of it. I suggest you keep an eye on that (there is a public comment period), because that will not be struck down and I guarantee that getting hit with it will hurt. Oh, and it'll probably be something like "be a model aircraft (with all the restrictions, including noncommercial use) or the drone and person have to be certified like aircraft and pilots" - not exactly "do whatever you want"

Comment: Re:Not a rule (Score 5, Informative) 199

FAA has no authority below the mandated altitudes for air travel.

Wrong. FAA's authority applies to any flying vehicle in the airspace of this country. Don't believe me? Here's the quote from the law that established the FAA:

The Administrator is authorized and directed to develop plans for and formulate policy with respect to the use of the navigable airspace; and assign by rule, regulation, or order the use of the navigable airspace under such terms, conditions, and limitations as he may deem necessary in order to insure the safety of aircraft and the efficient utilization of such airspace. He may modify or revoke such assignment when required in the public interest.

Property owners have air rights above their property up to the FAA's mandated altitudes or as locally mandated by code.

Nope. Another common misconception, but "he United States Government has exclusive sovereignty of airspace of the United States." (source).

Consider reading the Wikipedia page for some interpretation. Basically the idea is that you have airspace rights to the extent that you can use the space to have useful stuff on it (i.e., you can't build a 600 foot pole just to keep planes away, it has to be for some useful purpose). It's not at all clear that using drones grants you these rights, since they're definitely more aircraft than building.

So, the FAA should kindly go fuck itself. It does not tell us what we can do in the immediate vicinity around our homes or property.

If I want to hire a drone to do a fly through of my home, or my realtor offers to do it themselves, I will do it and the feds can shove their rules as far up their ass as they please.

Nobody's talking about flying a drone inside your house, they're talking about flying one over your house. You know, airspace. As far as thumbing your nose at the FAA - go nuts, but be prepared to win in court, suffer the consequences, or start a (successful) revolution. You could say the same thing about any other law or regulation - it's basically a question if whether you accept the rule of law or not.

Just so we're all clear on the sequence of events: the law creates the FAA and says "you regulate our airspace". The FAA, in the course of performing its legal mandate, creates a number of regulations (such as how pilots and aircraft are certified, standards for airports and navigation, etc) through a process called "rulemaking". They also issue more specific interpretations of the rules they've already enacted. (None of this is unusual; all federal agencies work the same way.) One such opinion decides that drones are basically model aircraft and that's OK so long as they follow the rules - one of which is no commercial use. The court decided that an opinion wasn't good enough here, so the FAA is going through the rulemaking process like they're supposed to. The end result will not be "yeah do whatever the hell you want", it'll probably be "be a hobbyist model aircraft (and comply with the rules, including noncommercial use) or get certified like an aircraft/pilot".

Comment: Re:that's not the FAA's job (Score 1) 199

"The United States Government has exclusive sovereignty of airspace of the United States." And they've delegated the administration of it to the FAA. The only air rights you have over your property are those you can reasonably use in connection with the property, e.g. adding another storey to your house. It's not at all clear that drones are more "stuff related to your use of the property" than aircraft - that's the question, right? (IANAL)

And it's 500 feet, unless you're in a "congested area" like a city (where it is 1000 feet). Even then, it doesn't apply if the aircraft is that low for the purposes of takeoff or landing, so everyone within a few miles of any runway threshold will have planes closer than 500 feet.

Comment: Re:Everyone here is embarassing themselves (Score 1) 310

Alright then. Let's see the video and cut all this other bullshit. We're all wasting our time listening to this he-said-she-said.

I will say that it's hard to believe that the drone was below 300'. Those things can go much higher than 300' (citation) so their lawyer is wrong when he says it's impossible. And if you believe the chopper pilot at all (you don't, I know - see below) it's hard to conclude that this guy wasn't at least above 1000 feet.

People are extremely quick to conclude that this guy is deliberately lying out of malice (because... you know, how could the police do otherwise?), when the much simpler explanation is that he's suffering from a sensory illusion and/or telling the truth (probably a combination). This chopper pilot may be a sworn officer, but probably hasn't ever arrested anyone in their life. Lots of cops (not the majority) are basically bullies who wanted to find a way to beat people up after high school, and fancy themselves the "thin blue line" and so on. This guy spends his days flying around, watching cars trying to flee and pointing lights at people trying to flee and so on and trying to direct units on the ground. What, precisely, is his motive for this malicious and planned setup? Honestly I think he was pissed about someone interfering with his safety and wanted them stopped before they hurt someone. I would be too - and in fact, I was last week when I was trying to land while backyard fireworks were coming up into the approach path. (The tower sent the police over to have a chat with them.)

I'm going to harp on this. What's the logic? As far as I can tell, it's:
a) Pilot says some stuff and his numbers are wrong in ways that are at least mostly explainable as an illusion
b) The accused say "no, that's not true" and their lawyer lies about the whole thing being impossible anyway (the 300' nonsense)
c) Therefore, the pilot deliberately fabricated things to get them arrested.

I don't see how that follows. Even if you forego the malice and say that he was arrested because the guy got the numbers wrong, that doesn't appear to be what happened (please, citations if I'm wrong - I may be). The arrest appears to be for doing something dangerous - I don't see how the specific altitude was relevant to the charge.

But you're right, there's a lot of questions about what exactly happened here... if only we had a system for discovering the truth about criminal incidents and deciding what to do...

Comment: Re:Jurisdiction (Score 3, Interesting) 310

I'm sorry, I'm not usually so harsh, but this is all completely wrong. I'm choosing to believe that you are just completely ignorant of aviation (most people are, I don't hold it against you). But please know the limitations of your knowledge especially when it comes to highly specialized fields with its own rules, customs, language, procedures, etc.

1) 1/2 mile line of sight is no problem for virtually any radio, not even for you cheap-ass blister pack FRS radios. Hell WiFi would probably work alright.
2) Nobody said the GWB was 2000 feet in the air. Listen to the radio recording, the guy was cleared for an altitude of 2000 feet (well, at or above, but for his purposes he wanted to be low). The GWB is how he's identifying his position to ATC - it's a VFR waypoint and mandatory reporting point for that part of the river. You're interpreting the "near" thing in the strangest way possible, at least in an aviation sense. Later on he mentions being at 800-1000 feet but that was much later.
3) They said nothing about Mach numbers. The guy thought he was looking at some military aircraft that was rather further away (and larger) than a tiny drone within tens of feet. The perspective information told him that the thing was basically coming from the ground, but it was probably just a few hundred feet below his altitude or less. Such a climb would certainly appear to be extremely fast if you were interpreting it as being some distance away. You know that commercial jets are going like 500 knots at 30,000 feet but they don't look that fast from the ground? Same phenomenon. This is one of a number of sensory illusions in aviation, most of which are more prevalent at night (this was midnight local time). People just aren't very good at dealing with large expanses of 3D in which things can be (almost) arbitrarily positioned - we do better with 2D and ballistics, which makes sense given our background, but isn't particularly useful for flight.
4) His "measurements" don't seem to be relevant to the arrest so I don't know why them being suspect matters very much. Knowing something is above, below, or at the horizon isn't a measurement - it's looking out the window. And if you're at 2000 feet, that's how you decide something is at 2000 feet. I'll admit that his relative measures are more suspect, as I'd expect them to be at night - but again they don't seem relevant. It's certainly far from evidence that they're deliberately trying to lie to arrest this guy. People fly into mountains because of these kinds of sensory illusions, you think they're just screwing with people when they do so? People really are eviscerating this pilot assuming he's their worst impression of a corrupt cop - if he's even a sworn officer, it's probably name only. I'd be surprised if he'd ever cuffed someone in his life.
5) Everyone seems to be repeating that the police approached the drone. Sorry, where is this coming from? That terrible Vice "article"? It has no citation for this, aside from the accused, and the transcript doesn't support it. Sorry to call you out specifically, since everybody's doing it, but I've seen no evidence of this particular statement. (Aside: it's pretty sad when the NY Post is far more informative than something at least trying to be legitimate.)
6) Every pilot knows everything is recorded, always. Everything. Always. The radios are recorded. All radar everywhere is recorded. The phones are recorded. If I call to get a damn weather briefing, it's recorded. The idea that they'd be surprised that there's a recording is beyond laughable.

I agree that this is more a FAA matter than a police matter. The police have no jurisdiction in the air, but that said the perpetrators were not in the air. This is, funnily enough, an area that the FAA is working on clarifying. That said, these guys should be happy that the city cops are the ones they're dealing with - the FAA would be substantially more unpleasant.

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