Of course, the plutonium in breeder reactors is an inseparable mix of isotopes which cannot be made to work in a nuclear warhead.
I wish that were right, unfortunately it isn't.
The US Dept of Energy has reported that fuel-grade plutonium could be made into a viable nuclear weapon
a potential proliferating state or subnational group using designs and technologies no more sophisticated than those used in first-generation nuclear weapons could build a nuclear weapon from reactor-grade plutonium that would have an assured, reliable yield of one or a few kilotons (and a probable yield significantly higher than that).
The main problem with 'reactor grade' or 'fuel grade' Pu is the high neutron flux causes a premature beginning to the chain reaction. As stated above, this and other problems (heat, radiation) can be solved relatively easily. Even if not solved, a 'fizzle' explosion is the likely result. Even such a fizzle would be incredibly destructive, 100-1000 tonnes TNT equivalent and I don't even mention the lethal neutron flux.
well.ets be honest here, scientist always have a habit of doing that when something they don't agree with is published.
No, that is not true. Scientists actually have a habit of looking at new ideas - they do that every day - and doing their best to evaluate the new ideas using a suite of rational and emperical methods. Just like in Open Source, a great new idea might occassionally be missed, but history shows that the scientific consensus is amazingly good at converging on what can be seen in hindsight to be the 'right' understanding.
". Not only does the article suggest that this "drive" violates conservation of momentum,"
There is nothing in Relativity that says this someone can't exploit the difference in frames.
A fair comment for you to make, relativity is a difficult subject and claims based on its theories are not easily tested using common sense. Unfortunately those who understand relativity know that the statement is completely wrong. Others have linked already to the views of a wide range of scientists with a better understanding of relativity than I.
It really is sad that NewScientist published this. When I was a grad student we used to get sent the crackpot letters addressed to the professors - its an education! In this case the 'crackpot' signs are all around.
Some/.ers commented that at least there were some experiments, presumably a reference to: "by mounting it on a sensitive balance, he has shown that it generates about 16 millinewtons of thrust, using 1 kilowatt of electrical power."
One of the many problems here is how incredibly easy it is to stuff up sensitive measurements. For example, I have seen electronic balances and other equipment read a lot more than 16mN in error due to em interference (could be the microwaves, could be slop-over RF, could be induction into the mains. Remember Cold Fusion? Did you know the neutron detectors they were using were incredibly sensitive to temperature? No? Nor did Pons and Fleischmann, unfortunately...
A key finding is that Vista will not just sustain the existing Windows economy, but create thousands of new jobs. Using a baseline for economic growth due to existing versions of Windows, the research firm determined that Windows-related employment would jump by 100,000 jobs next year.
However, we don't see any justification for this assertion. I am skeptical, not least because I expect Vista will take some time to displace XP.
One thing that will cause a fair bit of additional work is making existing windows apps run under Vista. However, this work is already going on. And in practice the work is done at the cost of those staff doing other things such as developing new features. That is, in effect the short term effect of Vista's introduction is to reduce the pace of development.
And good luck getting any information from a blacklist--they actively will not tell you the reason for the listing anymore because then (as they say) "spammers will use that information." Gee, doesn't help you fix any problems does it (if even you have a problem )?
And the worst bit is if you ask for information or try to explain why you should be removed, you are treated as a spammer along the lines of "well if you were a spammer you would say that". The anti-spam zealots are just really unpleasant to deal with, no matter how politely and professionally you approach them.
it's a flaw in how email was designed and evolved....you should think about telling (more aptly, "strongly recommending") to both Subscriber Subset A and Subscriber Subset B that they get your information from your newly setup and friendly RSS feed...
Email is broken, but RSS is not the answer - at least not in this case:
Subscriber Subset A who decide they no longer like their hometown's minor league baseball team and click the "This is Spam" button in their pretty little ISP-GUI inboxes
"Subscriber subset A" are a about a million miles from using RSS. This might change, but I don't think it will change soon. Anyone on slashdot will be comfortable with RSS - but we are not the problem group.
The two questions are: "given a particular chemical composition, what is the crystal structure? what are its likely properties?"
The scientists have a database of known crystal structures (plus some unspecified physics). Step 1 is to use 'datamining' techniques to generate a shortlist of possible structures for a given composition based on the database. Step 2 they perform quantum mechanical calculations to decide the likely properties (eg band gap).
I assume as step 3 they then investigate in more detail any materials which show signs of being interesting or matching the properties they are seeking. The methodology of steps 1-2 is necessarily guesswork not a definite answer. Nevertheless, for some time materials scientists, chemists and others have realised that there are very substantial benefits to narrowing down the possibilities before doing more in depth work.
Definitely not modded insightful by someone who understands. There's no engineer designing MOSFETs who is going to slap his or her forehead and say 'why didn't I think of that?'. CMOS design/fabrication is incredibly complex and doping profiles are optimised using multiple techniques. Silicon bipolar transistors are large and unsophisticated in comparison to the CMOS devices in your computer. I'm not saying these researchers aren't doing good work - but their techniques are not directly applicable to chip manufacture.
Sites with more links have more visitors (as defined by Alexa ranking, a rough tool at best) - big surprise , NOT. Everyone knows that sites with more inbound links tend to rank higher on the search engines and therefore get more visitors.
TFA then tries to make a big thing out of their 'discovery' that links are not the _only_ factor in the popularity (however defined) of a website. Again, completely obvious.
Then we hear that the correlation (not defined clearly) between links and 'traffic' (presumably actually some Alexa rank) is 0.8. Not clear what this actually means, but its hardly surprising the relationship between links and traffic isn't 1:1. Many factors will be causing this. For example, site-wide links off large sites make a huge contribution to the number of links but will make a smaller contribution to the target site's search engine ranking than the same number of links each from an individual site.
Re:Give me a break
on
The Expert Mind
·
· Score: 2, Informative
"If you think you can, you might, if you think you can't, you never will."
"Genius is one percent inspiration and ninety-nine percent perspiration." - Thomas Edison
"I am neither especially clever nor especially gifted. I am only very, very curious." --Albert Einstein
These quotes are all true (Einstein is making a very valid point about his methods). I'll try making my point in a different way - the quotes are from people who *also* had the massive talent. Which they naturally are modest about. In some ways, yes, these are people like you and me. But on the other hand they have talent which you or I do not. Let me take Einstein as an example because I am a physicist. I have put in a heck of a lot of work and I have enough talent to have a decent career in this field. But could I get to Einstein's level? No. Nor could I get to the level of the people one level down from that. With equal levels of effort and dedication, they just leave me behind. To talk to, as I have, someone like Neville Mott and see how quickly they grasp new ideas that I have spent years on is to realise that there is such a thing as talent. I have a some, but others have more.
This isn't a negative thing, nor is it a cop out. I still am happy and enjoy working hard to get many satisfying results. I just hate the idea that the fact I'm not in the running for a nobel prize and never will be is taken by so many people as equivalent to me not being as hard-working as those who are in the running.
I find the opposite true, that almost anyone, with enough work and effort, can achieve these mental/skill levels...
If I'll ever see someone like Mozart, I'd marvel at his/her skill, not jealous of their ability
Give me a break! You're saying you could be like Mozart if you really worked at it (even from a young age)? That is absurd.
Don't get me wrong I'm not suggesting the hard work, discipline, etc don't make a difference. They make a massive difference. But to say that the only reason my name isn't on everyone's lips as the latest musical sensation is because I didn't work at it enough is just wrong.
Re:The science says it does.
on
The Expert Mind
·
· Score: 1
The key term being "effortful study". The science almost directly contradicts what you said. The difference is the quality of the training. If you're training for hours and producing modest results, take a look at the way you train.
There's no doubt that quality of training counts, so do many other environmental variables. But you've missed my point which is that at the most elite level, it doesn't matter how effectively you train, how much dedication you have, whatever, most people simply cannot reach the top. Factors other than the quality and quantity of training, practice, experience will decide who gets to the top and who does not.
Are you telling me you are at the very top in your chosen field? Or that you could be if only you really tried? Maybe you could be, but I think for the rest of us its realistic to know we can do well but its not realistic to expect to be a superstar.
Hard work does not guarantee amazing results
on
The Expert Mind
·
· Score: 2, Insightful
While I believe, definitely, that it has to take work to master something, and that work is the defining characteristic of a grand master, it's also important to have some inborn ability.
Yes, that sums it up exactly. Inate ability is essential, as well as hard work over a long time, to achieve true mastery.
The thing that really annoys me is talented people (whether in sports, the arts, science, or any other intellectual area) who say "I got to the top of my chosen field through hard work". My problem is that there is a strong implication in that statement that anyone else could have done so if only they'd chosen to work that hard. This is simply not true. Yes, they have worked hard - but the difference between them and all the other people who worked equally hard is luck - the luck to have been born with more talent/aptitude.
The myth that it 'only' takes hard work to get the most outstanding results is a corrosive and unpleasant put-down for the vast majority of us who toil away for modest results. By all means acknowledge the dedication of those who reach the top, but remember they also partly owe their position to simple luck.
Thunderbird spam filter needs more than a little work - it just doesn't block spam effectively. I recently installed Cactus spam which is turning out to be the best spam filter I've ever used.
However, that's going to require OSS to start thinking about polish - making applications that Grandma can use. It's not impossible, but a lot of OSS projects need to concentrate on making applications that work well and look decent on Windows - even if we don't particularly care for the platform or the company that makes it.
This is the most critical point that is missed in OSS development. Its just tragic that there are so many projects where the features are better but its not smooth enough for low-tech users. Think of the biggest OSS successes - I mean the ones which have succeeded outside 'geek land' like Firefox - and you'll see they combine a really smooth user experience with active marketing. "Its technically better so they will come" is as dumb as "build it and they will come".
Fair points on collaboration - you are absolutely right that there are much better tools for collaboration. Especially within an organisation where we can specify a CVS system and train staff to use it. But, and this is my main point, this isn't how the vast majority of people work. They've all got office and send documents back and forward by email using track changes. Its a flawed system, but in practice for the most common purposes it works surprisingly well.
I'm not trying to argue that office is better, my main point is that until you can swap documents smoothly between openoffice and office, then openoffice will not be the preferred product for many small businesses.
To some extent its the old adage - your new product needs to be better, cheaper and (in software) fully compatible with the established player before people will switch. Two out of three will get you only a small niche.
Actually, there is a view that space tourism is the key to making space flight affordable. Space tourism - unlike satellite launches, or science - can grow to a large number of launches per year. Therefore economies of scale can come in to play.
According to this article http://www.spacefuture.com/archive/public_choice_e conomics_and_space_policy_realising_space_tourism. shtml space tourism is the key to economically viable space travel.
Low cost to orbit made possible by space tourism then opens up the really interesting space opportunities.
Our (very small) business recently migrated *away* from Open Office.
New staff were confused, couldn't do things the way they were used to. They arrive already knowing how to use word, excel, powerpoint (ugh! but its sometimes necessary) but give them OpenOffice and there is a substantial learning curve. Remember, what slashdot uber-geeks can learn in 5 seconds takes the average person 10 weeks.
Since changing to office our productivity on certain tasks such as collaboratively authoring documents has increased substantially. We just send the latest version and they send it back with the edits marked in track changes. Yes, all can be done using openoffice - but not when the customer or client doesn't have open office.
Openoffice has to be really, really easy for someone to use who is familiar with office (its getting closer, but a long way to go). And its ability to save to and read from office formats needs to be a lot better than it currently is.
Quick calculation: The big sail is said to generate 5000kW effective propulsion power at a speed of 10kts. Therefore it is exerting a force (force equals power divided by velocity) of about 100 tonnes.
(This doesn't take into account gusts nor higher wind conditions nor the angle between the kite and the direction of travel both of which would further increase the tension on the cable.)
Yes, that would require careful engineering.
I reported a *possible* disk problem on a poweredge where I couldn't easily take it down to do further testing. Without pushing Dell sent a replacement disk. This server wasn't covered by any special support contract, so I was impressed.
Slashdot Mirror
hmmm... yes. I guess this is security through obscurity http://en.wikipedia.org/wiki/Security_through_obs
I wish that were right, unfortunately it isn't.
The US Dept of Energy has reported that fuel-grade plutonium could be made into a viable nuclear weapon See for example http://www.nti.org/e_research/cnwm/overview/techn
The main problem with 'reactor grade' or 'fuel grade' Pu is the high neutron flux causes a premature beginning to the chain reaction. As stated above, this and other problems (heat, radiation) can be solved relatively easily. Even if not solved, a 'fizzle' explosion is the likely result. Even such a fizzle would be incredibly destructive, 100-1000 tonnes TNT equivalent and I don't even mention the lethal neutron flux.
No, that is not true. Scientists actually have a habit of looking at new ideas - they do that every day - and doing their best to evaluate the new ideas using a suite of rational and emperical methods. Just like in Open Source, a great new idea might occassionally be missed, but history shows that the scientific consensus is amazingly good at converging on what can be seen in hindsight to be the 'right' understanding.
A fair comment for you to make, relativity is a difficult subject and claims based on its theories are not easily tested using common sense. Unfortunately those who understand relativity know that the statement is completely wrong. Others have linked already to the views of a wide range of scientists with a better understanding of relativity than I.
It really is sad that NewScientist published this. When I was a grad student we used to get sent the crackpot letters addressed to the professors - its an education! In this case the 'crackpot' signs are all around.
/.ers commented that at least there were some experiments, presumably a reference to:
Some
"by mounting it on a sensitive balance, he has shown that it generates about 16 millinewtons of thrust, using 1 kilowatt of electrical power."
One of the many problems here is how incredibly easy it is to stuff up sensitive measurements. For example, I have seen electronic balances and other equipment read a lot more than 16mN in error due to em interference (could be the microwaves, could be slop-over RF, could be induction into the mains. Remember Cold Fusion? Did you know the neutron detectors they were using were incredibly sensitive to temperature? No? Nor did Pons and Fleischmann, unfortunately...
Thanks, good link. Anyone got any experience with Expression in combo with Visual Studio?
However, we don't see any justification for this assertion. I am skeptical, not least because I expect Vista will take some time to displace XP.
One thing that will cause a fair bit of additional work is making existing windows apps run under Vista. However, this work is already going on. And in practice the work is done at the cost of those staff doing other things such as developing new features. That is, in effect the short term effect of Vista's introduction is to reduce the pace of development.
And the worst bit is if you ask for information or try to explain why you should be removed, you are treated as a spammer along the lines of "well if you were a spammer you would say that". The anti-spam zealots are just really unpleasant to deal with, no matter how politely and professionally you approach them.
Email is broken, but RSS is not the answer - at least not in this case:
"Subscriber subset A" are a about a million miles from using RSS. This might change, but I don't think it will change soon. Anyone on slashdot will be comfortable with RSS - but we are not the problem group.
The two questions are: "given a particular chemical composition, what is the crystal structure? what are its likely properties?"
The scientists have a database of known crystal structures (plus some unspecified physics). Step 1 is to use 'datamining' techniques to generate a shortlist of possible structures for a given composition based on the database. Step 2 they perform quantum mechanical calculations to decide the likely properties (eg band gap).
I assume as step 3 they then investigate in more detail any materials which show signs of being interesting or matching the properties they are seeking. The methodology of steps 1-2 is necessarily guesswork not a definite answer. Nevertheless, for some time materials scientists, chemists and others have realised that there are very substantial benefits to narrowing down the possibilities before doing more in depth work.
Definitely not modded insightful by someone who understands. There's no engineer designing MOSFETs who is going to slap his or her forehead and say 'why didn't I think of that?'. CMOS design/fabrication is incredibly complex and doping profiles are optimised using multiple techniques. Silicon bipolar transistors are large and unsophisticated in comparison to the CMOS devices in your computer. I'm not saying these researchers aren't doing good work - but their techniques are not directly applicable to chip manufacture.
Sites with more links have more visitors (as defined by Alexa ranking, a rough tool at best) - big surprise , NOT. Everyone knows that sites with more inbound links tend to rank higher on the search engines and therefore get more visitors.
TFA then tries to make a big thing out of their 'discovery' that links are not the _only_ factor in the popularity (however defined) of a website. Again, completely obvious.
Then we hear that the correlation (not defined clearly) between links and 'traffic' (presumably actually some Alexa rank) is 0.8. Not clear what this actually means, but its hardly surprising the relationship between links and traffic isn't 1:1. Many factors will be causing this. For example, site-wide links off large sites make a huge contribution to the number of links but will make a smaller contribution to the target site's search engine ranking than the same number of links each from an individual site.
These quotes are all true (Einstein is making a very valid point about his methods). I'll try making my point in a different way - the quotes are from people who *also* had the massive talent. Which they naturally are modest about. In some ways, yes, these are people like you and me. But on the other hand they have talent which you or I do not. Let me take Einstein as an example because I am a physicist. I have put in a heck of a lot of work and I have enough talent to have a decent career in this field. But could I get to Einstein's level? No. Nor could I get to the level of the people one level down from that. With equal levels of effort and dedication, they just leave me behind. To talk to, as I have, someone like Neville Mott and see how quickly they grasp new ideas that I have spent years on is to realise that there is such a thing as talent. I have a some, but others have more.
This isn't a negative thing, nor is it a cop out. I still am happy and enjoy working hard to get many satisfying results. I just hate the idea that the fact I'm not in the running for a nobel prize and never will be is taken by so many people as equivalent to me not being as hard-working as those who are in the running.
Give me a break! You're saying you could be like Mozart if you really worked at it (even from a young age)? That is absurd.
Don't get me wrong I'm not suggesting the hard work, discipline, etc don't make a difference. They make a massive difference. But to say that the only reason my name isn't on everyone's lips as the latest musical sensation is because I didn't work at it enough is just wrong.
There's no doubt that quality of training counts, so do many other environmental variables. But you've missed my point which is that at the most elite level, it doesn't matter how effectively you train, how much dedication you have, whatever, most people simply cannot reach the top. Factors other than the quality and quantity of training, practice, experience will decide who gets to the top and who does not.
Are you telling me you are at the very top in your chosen field? Or that you could be if only you really tried? Maybe you could be, but I think for the rest of us its realistic to know we can do well but its not realistic to expect to be a superstar.
Yes, that sums it up exactly. Inate ability is essential, as well as hard work over a long time, to achieve true mastery.
The thing that really annoys me is talented people (whether in sports, the arts, science, or any other intellectual area) who say "I got to the top of my chosen field through hard work". My problem is that there is a strong implication in that statement that anyone else could have done so if only they'd chosen to work that hard. This is simply not true. Yes, they have worked hard - but the difference between them and all the other people who worked equally hard is luck - the luck to have been born with more talent/aptitude.
The myth that it 'only' takes hard work to get the most outstanding results is a corrosive and unpleasant put-down for the vast majority of us who toil away for modest results. By all means acknowledge the dedication of those who reach the top, but remember they also partly owe their position to simple luck.
Informative
Thunderbird spam filter needs more than a little work - it just doesn't block spam effectively. I recently installed Cactus spam which is turning out to be the best spam filter I've ever used.
Fair points on collaboration - you are absolutely right that there are much better tools for collaboration. Especially within an organisation where we can specify a CVS system and train staff to use it. But, and this is my main point, this isn't how the vast majority of people work. They've all got office and send documents back and forward by email using track changes. Its a flawed system, but in practice for the most common purposes it works surprisingly well. I'm not trying to argue that office is better, my main point is that until you can swap documents smoothly between openoffice and office, then openoffice will not be the preferred product for many small businesses. To some extent its the old adage - your new product needs to be better, cheaper and (in software) fully compatible with the established player before people will switch. Two out of three will get you only a small niche.
Actually, there is a view that space tourism is the key to making space flight affordable. Space tourism - unlike satellite launches, or science - can grow to a large number of launches per year. Therefore economies of scale can come in to play. According to this article http://www.spacefuture.com/archive/public_choice_e conomics_and_space_policy_realising_space_tourism. shtml space tourism is the key to economically viable space travel.
Low cost to orbit made possible by space tourism then opens up the really interesting space opportunities.
Our (very small) business recently migrated *away* from Open Office. New staff were confused, couldn't do things the way they were used to. They arrive already knowing how to use word, excel, powerpoint (ugh! but its sometimes necessary) but give them OpenOffice and there is a substantial learning curve. Remember, what slashdot uber-geeks can learn in 5 seconds takes the average person 10 weeks. Since changing to office our productivity on certain tasks such as collaboratively authoring documents has increased substantially. We just send the latest version and they send it back with the edits marked in track changes. Yes, all can be done using openoffice - but not when the customer or client doesn't have open office. Openoffice has to be really, really easy for someone to use who is familiar with office (its getting closer, but a long way to go). And its ability to save to and read from office formats needs to be a lot better than it currently is.
Oh yeah? Have you ever tried debugging without administrator privelege on a windows box?
Quick calculation: The big sail is said to generate 5000kW effective propulsion power at a speed of 10kts. Therefore it is exerting a force (force equals power divided by velocity) of about 100 tonnes. (This doesn't take into account gusts nor higher wind conditions nor the angle between the kite and the direction of travel both of which would further increase the tension on the cable.) Yes, that would require careful engineering.
I reported a *possible* disk problem on a poweredge where I couldn't easily take it down to do further testing. Without pushing Dell sent a replacement disk. This server wasn't covered by any special support contract, so I was impressed.