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Technology

MIT Combines Carbon Foam and Graphite Flakes For Efficient Solar Steam Generati 110

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:Completly Blindsided. (Score 1) 285

The school district wasn't blindsided. The county was.

I work at a school district, so let me tell you how public schools get their Internet. Obviously it's going to vary, but from what I've seen our situation is the most common.

Every building in a district runs fiber between their buildings to a central building where the district's servers are kept. It could be in the basement of the high school or some administrative building, but that's what happens. It's easy enough for the district to do capacity planning. Each school district may then connect to an intermediate school district, but ultimately then connects to the county's municipal network. This network is the ISP that connects every municipal office, such as city, village, police, fire, public works, etc. to the Internet. In my state, Michigan, the county connects to a statewide municipal network originally put in place to connect the public universities to the proto-Internet for research (our ISP, Merit, was founded in 1966).

In this story, the problem is at the county level, the middle man between the school and the state-wide network. This is not particularly surprising, since since in every case I've seen, the county is a) poorly funded, b) poorly staffed, and c) tends to be forgotten about. When a neighboring district went 1-to-1 at the high school level with lots of online classes, they did reasonable capacity planning for the district's small network and quadrupled the bandwidth from the high school to the district servers, and the district to the county (the district consists of 3 buildings on the same plot of land, so it was fairly simple). What they didn't do was consider that the county level needed upgrades as well. My district is about 8500 students across more than a dozen buildings, and this was about 200 students in just one building (grades 9 and 10). They were using about 90% of the bandwidth on our connection. That district got moved to a different connection pretty quickly, but until then nobody in our district could use the Internet during the school day.

Comment Re:Evolution (Score 1) 253

I think it's more likely that more people are becoming obese because of exactly one factor: age. They are living artificially prolonged lifetimes due to access to adequate food and to medicine. It's easier to get fat when you are 50 than when you are 30 because of the natural changes in your metabolism.

Comment Re:Evolution (Score 1) 253

:-)

You make it sound like starving people are getting fat too.

If they are becoming obese, the particular individual has a surplus of caloric intake, if only for this year or month. This is not to say that they have proper nutrition. So I am not at all clear that the fact that there is obesity in the third world is confounding evidence.

Comment Evolution (Score 1) 253

For most of the existence of mankind and indeed all of mankind's progenitors, having too much food was a rare problem and being hungry all of the time was a fact of life. We are not necessarily well-evolved to handle it. So, no surprise that we eat to repletion and are still hungry. You don't really have any reason to look at it as an illness caused by anything other than too much food.

Comment Re: If you pay... (Score 2) 15

Martin,

The last time I had a professional video produced, I paid $5000 for a one-minute commercial, and those were rock-bottom prices from hungry people who wanted it for their own portfolio. I doubt I could get that today. $8000 for the entire conference is really volunteer work on Gary's part.

Someone's got to pay for it. One alternative would be to get a corporate sponsor and give them a keynote, which is what so many conferences do, but that would be abandoning our editorial independence. Having Gary fund his own operation through Kickstarter without burdening the conference is what we're doing. We're really lucky we could get that.

Comment Re:One hell of a slashvertisement! (Score 2) 15

I think TAPR's policy is that the presentations be freely redistributable, but I don't know what they and Gary have discussed. I am one of the speakers and have always made sure that my own talk would be freely redistributable. I wouldn't really want it to be modifiable except for translation and quotes, since it's a work of opinion. Nobody should get the right to modify the video in such a way as to make my opinion seem like it's anything other than what it is.

Comment Re:If you pay... (Score 2) 15

Yes. I put in $100, and I am asking other people to put in money to sponsor these programs so that everyone, including people who did not put in any money at all, can see them for free. If you look at the 150+ videos, you can see that Gary's pretty good at this (and he brought a really professional-seeming cameraman to Hamvention, too) and the programs are interesting. Even if at least four of them feature yours truly :-) He filmed every one of the talks at the TAPR DCC last year (and has filmed for the past 5 years) and it costs him about $8000 to drive there from North Carolina to Austin, Texas; to bring his equipment and to keep it maintained, to stay in a motel, to run a multi-camera shoot for every talk in the conference, and to get some fair compensation for his time in editing (and he does a really good job at that).

Submission + - Open Hardware and Digital Communications conference on free video, if you help (kickstarter.com)

Bruce Perens writes: The TAPR Digital Communications Conference has been covered twice here and is a great meeting on leading-edge wireless technology, mostly done as Open Hardware and Open Source software. Free videos of the September 2014 presentations will be made available if you help via Kickstarter. For an idea of what's in them, see the Dayton Hamvention interviews covering Whitebox, our Open Hardware handheld software-defined radio transceiver, and Michael Ossman's HackRF, a programmable Open Hardware transceiver for wireless security exploration and other wireless research. Last year's TAPR DCC presentations are at the Ham Radio Now channel on Youtube.

Submission + - New released NOAA data now confirms decades long cooling (forbes.com)

bricko writes: National Oceanic and Atmospheric Administration’s most accurate, up-to-date temperature data confirm the United States has been cooling for at least the past decade.

Responding to widespread criticism that its temperature station readings were corrupted by poor citing issues and suspect adjustments, NOAA established a network of 114 pristinely sited temperature stations spread out fairly uniformly throughout the United States. Because the network, known as the U.S. Climate Reference Network (USCRN), is so uniformly and pristinely situated, the temperature data require no adjustments to provide an accurate nationwide temperature record. USCRN began compiling temperature data in January 2005. Now, nearly a decade later, NOAA has finally made the USCRN temperature readings available.

According to the USCRN temperature readings, U.S. temperatures are not rising at all – at least not since the network became operational 10 years ago. Instead, the United States has cooled by approximately 0.4 degrees Celsius, which is more than half of the claimed global warming of the twentieth century.

USCRN data debunk claims that rising U.S. temperatures caused wildfires, droughts, or other extreme weather events during the past year. The objective data show droughts, wildfires, and other extreme weather events have become less frequent and severe in recent decades as our planet modestly warms. But even ignoring such objective data, it is difficult to claim global warming is causing recent U.S. droughts and wildfires when U.S. temperatures are a full 0.4 degrees Celsius colder than they were in 2005.

Submission + - Forbes: Government Data Show U.S. in Decade-Long Cooling (forbes.com)

schwit1 writes: The National Oceanic and Atmospheric Administration’s most accurate, up-to-date temperature data confirm the United States has been cooling for at least the past decade. The NOAA temperature data are driving a stake through the heart of alarmists claiming accelerating global warming.

Responding to widespread criticism that its temperature station readings were corrupted by poor citing issues and suspect adjustments, NOAA established a network of 114 pristinely sited temperature stations spread out fairly uniformly throughout the United States. Because the network, known as the U.S. Climate Reference Network (USCRN), is so uniformly and pristinely situated, the temperature data require no adjustments to provide an accurate nationwide temperature record. USCRN began compiling temperature data in January 2005. Now, nearly a decade later, NOAA has finally made the USCRN temperature readings available.

According to the USCRN temperature readings, U.S. temperatures are not rising at all – at least not since the network became operational 10 years ago. Instead, the United States has cooled by approximately 0.4 degrees Celsius, which is more than half of the claimed global warming of the twentieth century.

Of course, 10 years is hardly enough to establish a long-term trend. Nevertheless, the 10-year cooling period does present some interesting facts.

Submission + - Can dogs sniff out computer memory like drugs? (providencejournal.com) 1

FriendlySolipsist writes: A dog can be trained to detect computer memory, say the Rhode Island State Police in taking delivery of the second such dog in the nation from the Connecticut State Police. Being able to find hidden computer flash memory cards hidden in drawers and over ceiling tiles will aid their fight against child porn, the police say.

But is there any scientific evidence that such a thing is even possible? Computer parts are made from plastic and metal like almost everything else in a home or office, and computer parts unlike organic plants give off no odor. Without any plausible scientific explanation for how a dog can detect computer parts, is this all just a legal sham to bypass Fourth Amendment probable cause warrant requirements, allowing the human handler to signal the dog based on exactly the kind of "police intuition" that violates constitutional rights?

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