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Comment Re:Quick LED question. (Score 1) 553

LEDs lose efficiency if they hot, so it sounds like you'd need a big heat sink for your close-packed array of 200 lights. Google for: LED "heat sink". Perhaps you could use several smaller arrays, bolted to the metal of your bike. Warm handlebars might be welcome in Winter.

Comment Re:Solar panels too? (Score 4, Informative) 553

Aren't some solar panels made with GaN as well? Will this help them too?

Looks likely. Cambridge are researching that too, e.g. both fields are covered by the following grant application.

The other approach to solar cells we will pursue is high-efficiency inorganic multilayer solar cells. The basic idea is that by stacking layers in the order of their bandgap, with the layer with the largest bandgap at the top, light is converted into electricity in the most efficient way. We propose to build an innovative multi-layer solar cell based on GaN/InGaN/Si. The GaN layer will absorb the UV part of the solar spectrum, the InGaN layer the blue and green parts and the Si layer the yellow, red and near-IR parts. The theoretical efficiency is above 60%. Such a cell would be too expensive for large-area applications, but would be designed to be used at the focus of mirrors that concentrate the solar light, which will make the technology competitive.

GaN-based white lighting is extremely efficient and if used in our homes and offices it could save 15% of the electricity generated at power stations, 15% of the fuel used, and reduce carbon emissions by 15%. However for GaN-based white lighting to become widely used in homes and offices we have to increase the efficiency still further and reduce the cost. We will research various ways to increase the efficiency. To reduce the cost we will grow GaN-based LED structures on 150mm (six-inch) silicon wafers instead of the current growth on two-inch sapphire wafers. This would reduce the LED cost by a factor of ten. Cambridge will grow such LED structures and UCSB will process them into LED lamps.

Details of Grant

Comment Re:Really? (Score 1) 165

So from what I can tell, reducing consumption (and waste) of a commodity is good for the economy, but not necessarily for the environment. However, switching to an alternative "cleaner" commodity that costs the same *is* good for the environment, but neutral to the economy.

Yes, and unfortunately No. "Switching to an alternative "cleaner" commodity that costs the same" increases demand for the clean commodity and hence slightly increases its price, while slightly decreasing demand for the dirty commodity and hence decreases its price. Basically whenever you do something green, the incentives shift slightly to encourage your neighbor to pollute more.

One example is that I ride a bike, so I don't need my resident's parking place. But it doesn't stay empty. What happens is that the slightly easier availability of local parking just tips the decision in favor of one of my neighbor's buying an additional car, and there is always someone else's car filling my "un-needed" parking space. Worse, because this other car buyer is less "green" than me, the car in front of my house is more polluting than any I would have bought and parked there. So my "green" buying decision is bad for the environment.

Comment Re:The Problem of Using a Number (Score 4, Insightful) 286

The problem with using a single number is simple: It is easily gamed and there's lots of incentive to do so

Exactly. And one easy way to game the system is to bet that the authorities will always act to keep markets stable, which you can do by taking risks that would otherwise be stupid. In other words, traders are incentivized to leech off the taxpayer. I'm surprised the crash took so long.

Comment Re:I love when an article... (Score 1) 263

There are many times I repeat the exact same many-step procedure in Office. Why doesn't Office notice and offer to make a macro or menu item out of what I'm doing?

Because that would be a big disincentive to upgrade. If Office N has created a lot of custom macros for you, you're unlikely to buy Office N+1 and risk them not working.

Comment Re:"I Canna Change The Laws of Physics, Captain!" (Score 1) 743

"no one should be killed or injured in a Volvo car."

Actually this laudable goal is very easy to achieve. Simply kill the driver and passengers before they get into the Volvo car. For example use a huge blender, then pour them through a window. Not so "stupidly ignorant" after all, Mr Reality Master!

Comment Suicidal Sharks (Score 1) 142

Mr Brown said nurse sharks and other species of carpet shark which spend most of their time lying on the bed of the tanks, could be the best barometers for the impact of those pop tunes. Their reactions will tell the researchers whether the sharks are enjoying the music or whether it turns them off.

Everyone knows sharks must swim or die and, when the alternative was Christmas pop songs, they've made their choice.

Comment No you won't (at least not for childhood vaccines) (Score 1) 737

Some of the happy ingredients you'll find in common vaccines are formaldehyde (poison) and thimerosal (poison) which breaks down into ethylmercury (poison) and also raw mercury (poison).

No you won't ...

Since 2001, with the exception of some influenza (flu) vaccines, thimerosal is not used as a preservative in routinely recommended childhood vaccines.

Mercury and Vaccines (Thimerosal)

Comment Popular literature is "Prior Art" (Score 1) 75

While it's not an obvious source of comedy, internationally-recognized patent law is actually a rather funny thing. Just ask Danish engineer and inventor Karl Kroyer, whose method of raising sunken vessels from the ocean floor failed to obtain a patent because of a comic strip.

The German patent office denied Kroyer's claim based on the patent law concept of "prior art," which essentially means you can't patent an idea that someone has publicly described in the past, even if that idea wasn't patented.

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