I think, for some, the choice between Apple and Wal-Mart is a choice between the lesser of two evils. It's like the two party system of the record industry. Which is worse, DRM or censorship? Sure, you can vote for Amazon, but that would just be throwing your vote away.
Whispering something in my ear is a pretty good one, depending on what you say. "Hey, wanna go make out?" would certainly get my attention, and I probably wouldn't misinterpret it. Though for clarification I might respond, "Maybe. Who with?";)
Unless you have a very vivid imagination.
"Did you just say something?"
"Yeah, I said, 'Hey, wanna let me out!' This is my floor"
(moves aside to let pretty girl off of elevator)
The materials they are testing would extract up to 20 times more power from radioactive decay than thermoelectric materials, they calculate.
Wikipedia says, "most RTGs have efficiencies between 3-7%" Since 20x7%=140% I don't think that's the value they are using. I think they are using 3% efficiency since that makes their discovery look good. That gives this new material a theoretical efficiency of 60%. This is analogous to an engine's Carnot efficiency and therefore I expect it to be far less in reality.
Let's assume the material is as efficient in reality as a steam turbine (40%). Then yes, it will be more efficient than current nuclear power plants. However, instead of the power plant releasing heat energy into it's surroundings, it's releasing radiation.
No problem, we will just surround the thing with lead so the radiation doesn't hurt anybody. That won't work, because without a place for the radiation to go the system doesn't work. The radiation will just bounce off the lead and cancel out in a closed environment (once again I'm not a nuclear physicist). You still need to get rid of it, convert it to heat, bury it in a mountain, or radiate it into space. How much does that effect the systems efficiency?
I'm betting on this material having a practical efficiency of around 15%. It will be better than an RTG but not good enough to replace current power plants. I make this statement mostly because it sounds similar to photovoltaics.
What *I* want to know about is how effective this material is as a radiation shield. Something that can both protect you from radiation and generate electricity seems awfully handy.
I'm guessing it's only slightly more effective as a radiation shield as it is at producing electricity. (i.e. radiation not turned into electricity passes through the material.) But I could be wrong.
The steam turbine system is horrendously inefficient.
Compared to what? I have news for you. Steam Turbines are one of the most efficient engines we have. That's why we use them!
The second law of thermodynamics says that no engine can be 100% efficient. The reason is, a 100% efficient engine would require an infinitely hot source of energy and infinitely cold surroundings, assuming there is no friction. Carnot, says that the best we can hope for is more like 60-70% efficiency, and Rankine, suggests that a more realistic number is somewhere between 40-50%. That "inefficient turbine" you speak of is 40% efficient in reality. That's pretty good considering the best we can hope for is 60-70%.
I am not a nuclear physicist, but the laws of thermodynamics still apply. We can still only hope for 60-70% efficiency, but for various reasons we still won't be able to archive this. Now, instead of letting "most of the energy evaporate off the cooling tower" we will be radiating it to the surroundings instead. Fine for spacecraft, not fine here on Earth. Even though this technology sidesteps the creation of thermal energy it still must obey the laws of thermodynamics.
I think you are confusing the first rockets with the first atomic bomb. The first rockets were developed by the ninth century Chinese. Good point, none the less.
As I understand it, these companies both plan on sending people straight up and returning them to the same place they took off from. This is wonderful, but impractical for anything but a joy ride. How about creating something that lands you at some other place on the earth's surface? I don't even care if it can only travel from East to West.
This is not new and pioneering technology. There are companies that take similar surveys for market research purposes. Have you ever been asked to take a survey at a mall? Have you ever been at a bar when a beautiful woman with a tablet computer asks you to take a survey about cigarettes? I have. The Government is wasting billions of dollars to develop technology that has existed for years.
Why doesn't the government just outsource the whole census to a market research company and be done with it?
My co-workers and I have concluded that differential equations is best taken at a community college by the professor who is also a part time high school math teacher. We all either struggled or flunked it at the big universities and took it at a community college and understood it right away. I don't know why, but the more prestigious the school is the worse it is at teaching this subject.
While I understand the some of the great minds we pay to teach us may not me native English speakers, I also note that I once had a Chemistry TA that I swear only knew the words,"No, what are you doing! Read the lab manual!" In that order.
Sounds simple, but when you are studying 18 hours a day it's not quite practical. Therefore, my senior year I came up with a list of general core classes I should have taken to meet women:
1. Philosophy of education
2. Philosophy of nursing
3. Animal ethics
4. Introduction to communications
5. Introduction to psychology
Yes, I know it's sad I came up with this list. All of these classes should count as a humanities credits in major universities' science and engineering programs. I did take the communication and the psych classes. I found that it's best if these classes had some lab time or group projects so you can interact with your classmates. They usually don't. You also might have a hard time explaining why you are the only male in the philosophy of education class and your major is not education.
Open Mesh appears to be just what I am looking for. The only thing that concerns me is the Open Mesh hardware appears to be Meraki hardware with OSS. Are they buying Meraki routers, hacking them, and reselling them? Will Open Mesh suffer the same fate as the author of this article, or do they have a separate supply chain?
until I read this article. My building is going condo and I am considering bringing up the concept of a building wide wireless network at our first board meeting. I am even toying with the idea of sharing with the neighboring buildings. The only commercial product I have been able to find is Meraki. Does anybody have any other suggestions?
Please forgive my English, it's Monday.
Slashdot Mirror
It was a joke you clearly didn't get. It's funny because I'm pointing out where my analogy ceases to apply.
I think, for some, the choice between Apple and Wal-Mart is a choice between the lesser of two evils. It's like the two party system of the record industry. Which is worse, DRM or censorship? Sure, you can vote for Amazon, but that would just be throwing your vote away.
I like the new format. It's very clean looking.
A site exists for just such a concept. It's called the Halfbakery.
Hey, if Pantone can copyright a color, what's to keep T-Mobile from trademarking one?
In my day it was cows instead of pigs. You turned them loose on the second floor because, as rumor has it, cows can walk up stairs but not down.
I seriously doubt this ever happened. I think it's just a rural legend.
"Did you just say something?"
"Yeah, I said, 'Hey, wanna let me out!' This is my floor"
(moves aside to let pretty girl off of elevator)
I'll believe it when I see a reference. If the lead absorbs the radiation where does the energy go?
On a hot sunny day, do you wear a black shirt or a white one? Why?
Let's assume the material is as efficient in reality as a steam turbine (40%). Then yes, it will be more efficient than current nuclear power plants. However, instead of the power plant releasing heat energy into it's surroundings, it's releasing radiation.
No problem, we will just surround the thing with lead so the radiation doesn't hurt anybody. That won't work, because without a place for the radiation to go the system doesn't work. The radiation will just bounce off the lead and cancel out in a closed environment (once again I'm not a nuclear physicist). You still need to get rid of it, convert it to heat, bury it in a mountain, or radiate it into space. How much does that effect the systems efficiency? I'm betting on this material having a practical efficiency of around 15%. It will be better than an RTG but not good enough to replace current power plants. I make this statement mostly because it sounds similar to photovoltaics.
We also signed some treaties that limit the amount of "bomb-grade" material we can produce.
The second law of thermodynamics says that no engine can be 100% efficient. The reason is, a 100% efficient engine would require an infinitely hot source of energy and infinitely cold surroundings, assuming there is no friction. Carnot, says that the best we can hope for is more like 60-70% efficiency, and Rankine, suggests that a more realistic number is somewhere between 40-50%. That "inefficient turbine" you speak of is 40% efficient in reality. That's pretty good considering the best we can hope for is 60-70%.
I am not a nuclear physicist, but the laws of thermodynamics still apply. We can still only hope for 60-70% efficiency, but for various reasons we still won't be able to archive this. Now, instead of letting "most of the energy evaporate off the cooling tower" we will be radiating it to the surroundings instead. Fine for spacecraft, not fine here on Earth. Even though this technology sidesteps the creation of thermal energy it still must obey the laws of thermodynamics.
I think you are confusing the first rockets with the first atomic bomb. The first rockets were developed by the ninth century Chinese. Good point, none the less.
As I understand it, these companies both plan on sending people straight up and returning them to the same place they took off from. This is wonderful, but impractical for anything but a joy ride. How about creating something that lands you at some other place on the earth's surface? I don't even care if it can only travel from East to West.
If Six Sigma can do this for Motorola, imagine what it can do for your company!
This is not new and pioneering technology. There are companies that take similar surveys for market research purposes. Have you ever been asked to take a survey at a mall? Have you ever been at a bar when a beautiful woman with a tablet computer asks you to take a survey about cigarettes? I have. The Government is wasting billions of dollars to develop technology that has existed for years.
Why doesn't the government just outsource the whole census to a market research company and be done with it?
Google has been using this technology for years.
SAP already holds the patent on this business method. Let's just hope Microsoft can at least make it's modular product usable.
My co-workers and I have concluded that differential equations is best taken at a community college by the professor who is also a part time high school math teacher. We all either struggled or flunked it at the big universities and took it at a community college and understood it right away. I don't know why, but the more prestigious the school is the worse it is at teaching this subject.
While I understand the some of the great minds we pay to teach us may not me native English speakers, I also note that I once had a Chemistry TA that I swear only knew the words,"No, what are you doing! Read the lab manual!" In that order.
Sounds simple, but when you are studying 18 hours a day it's not quite practical. Therefore, my senior year I came up with a list of general core classes I should have taken to meet women:
1. Philosophy of education
2. Philosophy of nursing
3. Animal ethics
4. Introduction to communications
5. Introduction to psychology
Yes, I know it's sad I came up with this list. All of these classes should count as a humanities credits in major universities' science and engineering programs. I did take the communication and the psych classes. I found that it's best if these classes had some lab time or group projects so you can interact with your classmates. They usually don't. You also might have a hard time explaining why you are the only male in the philosophy of education class and your major is not education.
Open Mesh appears to be just what I am looking for. The only thing that concerns me is the Open Mesh hardware appears to be Meraki hardware with OSS. Are they buying Meraki routers, hacking them, and reselling them? Will Open Mesh suffer the same fate as the author of this article, or do they have a separate supply chain?
until I read this article. My building is going condo and I am considering bringing up the concept of a building wide wireless network at our first board meeting. I am even toying with the idea of sharing with the neighboring buildings. The only commercial product I have been able to find is Meraki. Does anybody have any other suggestions?
Please forgive my English, it's Monday.
OOPS!
Methane and Propane have a pretty high hydrogen to carbon ratio and the technology already exists to use them automobiles.
There, fixed it.