I'm just getting into Agent Based Modeling myself and I had exactly the same thought... why would they use the name of an established tool; especially when there are similarities in the concepts. This seems like a recipe for confusion.
A good first check when starting an open project is to check propesedprojectname.org and see if there's anything active there. Or even just Google it - if another project shows up near the top with the same name, it's probably a good idea to pick another name.
I'm sure there are plenty of synonyms for "swarm" that capture the idea, if not an alternate spelling.
But like you said, it does sound like an interesting project.
It's also important to remember that, "All models are wrong. Some are useful."
It's impossible to build a "model of everything" that will capture every aspect of reality - short of constructing a new universe and running it to completion. So, when you build any model, there is a lot of simplification, assumption, extrapolation, and "best guessing" that has to happen. This doesn't mean that a model is invalid or useless. Rather, a model that works well over a certain domain (even over many iterations and permutations of inputs) may still not reflect what actually ends up happening.
You do the best you can and try not to simplify away or assume away critical elements of the system you're modeling.
Thankfully (in a human suffering sense), we haven't had many serious pandemics where we've captured a wealth of data. However, from a modeling point of view, that leaves only a limited amount of data you have to work with. So you verify the model works the best you can based on your understanding of the real-world system, then validate it against as much real data as you can, and then you hope that it accurately predicts what will happen as the new potential pandemic unfolds.
The model will not be perfectly accurate, but hopefully it will help guide policies better than "gut feel" and "blind guessing".
Another favorite quote: Making predictions is a tricky business, especially when it's about the future.
What war was "unjustified"? Afghanistan was a response to the government of that country harboring an organization that murdered 3,000 people.
You mean the government that offered to turn over Bin Laden if the US could make a convincing case that he was involved in the attacks? I suppose there's a lot more fun and money in bombing and occupying a country than faxing over some documents with the evidence.
Remember: "And, again, I don't know where he [Bin Laden] is. I -- I'll repeat what I said. I truly am not that concerned about him." Bush, 2002
Certainly seems worth the price we continue to pay. What was it, 17 more fatalities this month alone?
As it is now, Universities generally set up some sort of portal through which students can access all the publishers they're subscribed to. Generally, these portals blow. My standard procedure is to google what I'm looking for, then when I find the exact title, issue, page, head to my college library portal.
Have you looked at scholar.google.com? In the preferences, you can tell it what libraries you have electronic access through, then when you search for articles, if it's available through your school's library, a link appears next to it. Log in once, and it seems to persist from then on.
I've found this a great way to get direct access to works. And if you notice the pattern of how it proxy's into the source site, you can often figure out how to adjust a URL, adding the proxy info for your school, to get the PDF, even if google scholar doesn't know your school has access.
and it seems rather odd to me that we could've had a significant population of ancestors that failed to leave a fossil record.
It's not really so odd. First, however, is the assumption that there is a significant population who didn't leave fossils. It's probably more likely that there are fossils and they just haven't been found. The Earth is big and only a small percentage of it has been searched for fossils.
Then you have to consider that not all geologic structures and death conditions are conducive to fossil formation. Go out into a wild area today and count the number of animals you find. Then count the number of somewhat intact carcasses you find. You won't find many. So of the critters out there alive today, only a tiny percentage of them will end up as fossils in another few million years. On top of that, if the places humans like to live today were in similar conditions (near large sources of water, for example), there's a good chance that we've built over any fossils many times over.
I suspect that if you made a Drake-Equation like formula for predicting finding fossils of any particular type that even if many fossils might exist, very few of them would be found. Consider that of the millions of A. afarensis that probably existed, we have only found a handful of their fossils.
So sure, there is a gap, but there's a pretty reasonable explanation for that gap. Until we have exhausted such possibilities, and without startling evidence to the contrary, we can't seriously claim that the gap in the fossil record is caused by divine or extra-terrestrial intervention.
What finally worked for me was to take the relative's computer, fix it, then just keep it for a few weeks before returning it. After doing that a few times nobody came to me any more to fix their computers any more. It helped that my mom would tell people that I've been working a lot lately and just haven't had time to do much else.
Just imagine: math textbooks with problems that you can't just solve right away!
Did you ever get to the end of the textbooks? That's what always bugged me... all the really good stuff was in the back and we never, ever got there.
Now that I'm much older and somewhat wiser, I work the problems in the back on my own now... I wish I'd thought of that 30 years ago... Of course now, most textbooks I use start out pretty interesting and only get harder as you get through them!
no, it was a network that had him as the "caretaker". Despite the methods, from what has been said, what he was doing was trying to protect the network. As a "caretaker", it's his job to do what he must to protect the network.
Actually, all of his authority with respect to this network come from his supervisor/manager. He only has the authority to "do what's best for the network" as long as it's still granted to him by his supervisor. As soon as his supervisor revokes that authority, he no longer has the privilege of deciding what is best for the network.
After all that, he was just being a dick, and it's stupid to be a dick to people who can have you locked up in jail. This may be United States, but it's not the United States you were (probably) taught about in grade school.
Take Conway's game of life, for example. Given a non-trivial starting arrangement, without actually running through all the iterations, can you predict the state the system will stabilize at? Can you even predict (for non-special cases) if it will ever stabilize?
I'm risking a big "whoosh" here, but aren't you simply restating the premise behind the halting problem?
As for The idea is that by starting with something very simple, you can get very complicated behaviour. The problem is, there aren't any proper mathematical tools for predicting that behaviour, except in very simple cases. The best you can do it try it out and see..
I haven't done much directly with CA, but I have dabbled in agent-based simulation. It seems to me you're describing "emergence". But I think it might be at least slightly more useful than string theory. Using ABS, one thing you can try to demonstrate is a "minimum set of rules" needed to generate a certain seemingly complex behavior that has been observed in reality. Having done so doesn't mean that you've actually found the actual rules that drive the behavior of the system, but it serves a good starting point for understanding how that system works.
You seem to think that a tariff increases the efficiency of the Japanese economy. If that's true, then why not double, triple, or quadruple it? By your logic, since the auto industry is a greater benefit to Japan's economy than other possible uses of their money, they should raise the tariff to infinity and reap the rewards.
Do you really live your life thinking so linearly? That if a little is good then more must be better? That if a little is bad then more must be worse?
Most but the simplest of situations involve complex systems with feedback loops and non-linear effects. A very simple example is water consumption. With a total lack of water, you'll die. Drink too much water, and you'll die (hypernatremia). So clearly, you should consume some water, but not too much. By your stated logic, we should all drink as much water as possible because a little is good for us... or we should drink none?
It's the same with protectionism. For the economy as a whole, some protectionism is good. Too much drives inefficiencies and lop-sided economies. Too little and your economy is too easily ravaged by external forces; also leading to unstable economic conditions. Japan was served pretty well by its protectionist policies for its auto sector; as it now dominates the world.
Finally, "economic efficiency" is not necessarily a good ultimate goal for economic policy. Consider that farming is labor-intensive; if we wanted highest efficiency, we'd outsource all of our farming to other countries where the labor is cheap and the soil requires less treatment. I hope you can see the stupidity of an argument for doing so.
But of course, I'm sure laissez-faire is the best overall. That's why we should have football games with no rules and no referees... with each player working towards his own best interest the invisible hand will magically guide them to a perfect game of football.
If you wait long enough, you'll die anyway, so why bother eating and maintaining your health?
Tariffs discourages trade, but it's not true that that hurts everyone. Sure it can be mathematically shown (over a limited range, with linear assumptions, ceteris paribus, and all that) that removing tariffs and quotas lead to more trade. However, that says nothing about the quality of the economic activity or the distribution of the benefits of the trade across the population.
The Japanese car industry is an excellent counter-example to your point. It was carefully protected with tariffs for several decades and it is now one the dominant automobile producers in the world. Having this strong domestic industry does more for Japan's economy as a whole than would having the slightly cheaper cars that the lack of tariffs would have permitted.
producers who decided Americans were too stupid to know what a Newton is.
Of course we know what a Newton is... you just have to decide if you're going to go with one of the newer fruit varieties or to stick with the classic Fig.
I love how they change the contract after you have agreed to it.
I think a lot of these anti-consumer contracts have language that says that they can change the terms of the contract. It's strange, like self-modifying code.
I use a cheap, no-contract (no more than month to month) cell phone company (http://www.virginmobile.com/). Sure it comes with a bit of a lame phone (target market is teenagers), but I can dump them today if I want to. I'm amazed at some of my friends who wonder why I don't get a nicer phone "for free" and sign up with one of major carriers. They complain about their crappy broken phone they can't replace (because they're under contract) or the phone bills that have hundred dollar calls from foreign countries that the company won't dismiss and threaten to send collections...
When my $20 phone finally craps out (had it for over a year now.. no problems), I think I'll try these guys: http://www.straighttalk.com/ServicePlans, relatively cheap decent phones and $45/month unlimited everything. Either that or maybe cricket (http://www.mycricket.com/).
I had Verizon once, and they were okay. I suppose if they come out with a decent phone and a $45/month for everything plan (with no contract), I'll think about going back.
One of the nice things about Virgin Mobile is that if something happens to your phone, you can be back up and running in about as much time as it takes you to buy a phone at the store. I was having a party at my house and an hour before people started showing up, I stepped on my phone and broke it. I quickly ran to a local store and had phone service in about 20 minutes; only missed 3 calls asking for directions. I now keep a spare cheapie in case something like that happens again or if an out-of-country guest needs a phone while they're visiting. I just put $20 on it for them and they're good for a while without worrying about international rates.
In most local school districts teachers are no more permitted to use cell phones in class than students. Sure, it would be a minor inconvenience when they have a break, but their classrooms and offices likely already have phones in them.
The problem with this is that most teachers I know (I used to date one) practically live in their classrooms... they are always there, between breaks, during "off hours", during lunch, and before and after class. There's no reason they shouldn't be able to use their phones during those times.
If a kid is distracting itself when it should be learning, that's it's problem (I used to read science books in my lap during social studies). If it's distracting other students with a phone, then you do the same thing you do when it's distracting other students with anything else... take the distraction away, or send the kid away. The teacher I dated would take away cell phones, ipods, etc, and require the parent to come pick them up from the school. If the kid wouldn't give up the item, she's send the kid to the office.
My teachers used intercept any notes passed in class and read them aloud. I see no reason why they can't do that with text messages too.
They are required in all first-world nations, most second-world nations and some developing countries are catching up fast. My point is that you limited specifically to the US, something which Europeans tend not to do in a matter like this.
I think he was actually trying to avoid making sweeping statements about the state of the world as a whole, but instead was talking about what he had direct knowledge of.
I can see how it might have come off that he was implying that the US was superior for requiring catalytic converters, leaving open the question of whether other countries did. But I do not think that was his intent.
I truly think this was a USian trying to be sensitive to the fact that the US is not the world. That's far better than the typical stereotypical American who thinks the way it's done in the US is the only way, or simply assumes that everyone does it the same way.
The problem is that things in the physical world are rarely binary. Sure, an "on" might be the laser bounces back and an "off" is where the laser passes through. But what's the quality of the holes made and what to their boundaries look like. I'm guessing that the light reflected back is never 100% and the light that goes through is never 0%, but rather there are fuzzy boundaries. If the laser that does the burning doesn't do a good job on the boundaries between 1's and 0's then after some degradation in the material, a reading laser might have trouble figuring out if 50% should be a 1 or 0.
There's a simple fix to that (that I'm quite sure is already in place): Simply charge for peak hour usage for industrial uses. Then the aluminum refinement will take place from 9pm-5am.
The aluminum plant where most of my family worked (where Google now has a facility) ran 24 hours/day. It would be too costly to heat things up then let them cool off during the day just to heat them back up again.
Most of these plants are located very close to electricity production (this one is within eye-sight of a hydro-power dam) and most likely use sophisticated financial models to determine the price they end up paying for power.
Well, I'm not as agile as I used to be, so I probably drop 2 or 3 bulbs a year.
However, I'm not convinced that in the complete lifecycle of the products that CFLs are really that much more efficient.
The CFLs appear to have a more complicated manufacturing process with more exotic materials (electronics, mercury).
The consider the packaging. Most CFLs I've seen are encased in that clamshell plastic. That, when coupled with the fact that most of them are larger than their incandescent counterpart, means that it takes a much larger carton, or more cartons, to ship the same number of bulbs. Consider the number of incandescent bulbs that would fill one ship. You'd need at least 2 ships to transport as many CFLs. Plus, with being heavier, they require more energy to transport.
Some of that is probably offset by the claims of longer life when compared to incandescent, but I'm not experiencing that.
On top of all that, I can't use the CFLs on my motion sensing switch, they produce inferior light, and cause a hazmat condition when I drop one (and I worry that my cats will ingest the mercury when they walk over the area and later lick their paws - how can I know I got all of it?)
Don't get me wrong, I'm all about doing things more efficiently, and I even have several CFLs in my house. I'm just not convinced they're as wonderful at saving energy as the industry claims - especially when you consider them with their end-to-end supply chain.
The physics you're looking for here is impulse, specifically, the change in p = mv over time.... This also happens to be the same reason that you have to follow through on your swing while hitting a baseball or tennis ball or whathaveyou to get the longest distance.
Thanks! The example I thought of first was the PLF (Parachute Landing Fall) where a military paratrooper is supposed to land in such a way that the impact with the ground is spread along the parachutist's body. http://en.wikipedia.org/wiki/Parachute_Landing_Fall It's an easy example from my own life... and when I could actually pull one off, the landing WAS a lot better.
Physics: learn it, use it, benefit from it. (hint: application of kinetic energy would be a starting point to understanding this)
I don't think it's as simple as that.
I'm no physicist but I would suspect that there is a great deal of difference between firing a frozen chicken and a thawed chicken at something. With enough velocity, of course, the differences in outcome will not be very much. But if you give the chickens progressively less velocity at impact, I think you'd find the frozen chickens still penetrate the glass at some levels of kinetic energy where the thawed chickens would not.
My reasoning for this has to do with differences in how the kinetic energy of the chicken is imparted to the windscreen, both through time as well as the area of impact.
The body of frozen chicken will "give" much less than the body of a thawed chicken, so the windscreen has a much shorter period of time to absorb kinetic energy of the chicken. Also, due to that lack of give, the kinetic energy of the chicken's body will be spread over a larger area of the windscreen.
If I drop a 5 kg bag of laundry on my car's windshield from my roof, it will bounce off the windshield and leave it intact. If I drop a 5 kg pipe wrench from the same height, it will most likely shatter the windshield. It's the same idea. With the bag of laundry, the windshield gets more time and more area to absorb the kinetic energy, with the wrench, not as much. Though maybe if I dropped both from a 10 story building, the windshield might not survive it either way.
This isn't simply a matter of an application of equal amounts of kinetic energy. There are a lot of things going on at the point and time of impact that can alter the outcomes... within a certain range of energies.
Last time I checked the air france black box recorder hasn't been located let alone pulled out of the ocean. Without having the black box how can the NTSB be making speculations as to the cause of the downed flight?
Well, considering the NTSB is a part of the US government, it could be in their interest to make speculations that make a foreign plane manufacturer look bad in order to make a domestic manufacturer look more desirable.
Why would you want an iPhone on T-Mobile when you can already get an Android handset?
Why not? Most consumers make only barely rational choices based on a myriad of impulses they are hardly aware of. This person wants an iPhone and wants to use it on T-Mobile. You probably want a different combination. What makes your choice any more or less rational than this persons?
When your math teacher only cares about "feelings" and not objective laws of mathematics, it doesn't matter that he followed his Union leader's instructions to vote for Obama, you'll still get morons coming out of the school system.
Have you ever actually worked with teachers? (not as a student but as a coworker?) They're amazingly strong-headed, stubborn, surly, and resistant to people telling them what to do. Their union might suggest they vote one way or the other, but if anything, they're likely to vote against that just to resist being told what to do.
I was in a job where I ended up in an education union. Really, all it meant was another line in my pay-statement where money was taken out, and a bit of "junk mail". The union certainly never told me how to vote, nor would I have listened or cared if it had.
Slashdot Mirror
I'm just getting into Agent Based Modeling myself and I had exactly the same thought... why would they use the name of an established tool; especially when there are similarities in the concepts. This seems like a recipe for confusion.
A good first check when starting an open project is to check propesedprojectname.org and see if there's anything active there. Or even just Google it - if another project shows up near the top with the same name, it's probably a good idea to pick another name.
I'm sure there are plenty of synonyms for "swarm" that capture the idea, if not an alternate spelling.
But like you said, it does sound like an interesting project.
It's also important to remember that, "All models are wrong. Some are useful."
It's impossible to build a "model of everything" that will capture every aspect of reality - short of constructing a new universe and running it to completion. So, when you build any model, there is a lot of simplification, assumption, extrapolation, and "best guessing" that has to happen. This doesn't mean that a model is invalid or useless. Rather, a model that works well over a certain domain (even over many iterations and permutations of inputs) may still not reflect what actually ends up happening.
You do the best you can and try not to simplify away or assume away critical elements of the system you're modeling.
Thankfully (in a human suffering sense), we haven't had many serious pandemics where we've captured a wealth of data. However, from a modeling point of view, that leaves only a limited amount of data you have to work with. So you verify the model works the best you can based on your understanding of the real-world system, then validate it against as much real data as you can, and then you hope that it accurately predicts what will happen as the new potential pandemic unfolds.
The model will not be perfectly accurate, but hopefully it will help guide policies better than "gut feel" and "blind guessing".
Another favorite quote: Making predictions is a tricky business, especially when it's about the future.
What war was "unjustified"? Afghanistan was a response to the government of that country harboring an organization that murdered 3,000 people.
You mean the government that offered to turn over Bin Laden if the US could make a convincing case that he was involved in the attacks? I suppose there's a lot more fun and money in bombing and occupying a country than faxing over some documents with the evidence.
Remember: "And, again, I don't know where he [Bin Laden] is. I -- I'll repeat what I said. I truly am not that concerned about him." Bush, 2002
Certainly seems worth the price we continue to pay. What was it, 17 more fatalities this month alone?
As it is now, Universities generally set up some sort of portal through which students can access all the publishers they're subscribed to. Generally, these portals blow. My standard procedure is to google what I'm looking for, then when I find the exact title, issue, page, head to my college library portal.
Have you looked at scholar.google.com? In the preferences, you can tell it what libraries you have electronic access through, then when you search for articles, if it's available through your school's library, a link appears next to it. Log in once, and it seems to persist from then on.
I've found this a great way to get direct access to works. And if you notice the pattern of how it proxy's into the source site, you can often figure out how to adjust a URL, adding the proxy info for your school, to get the PDF, even if google scholar doesn't know your school has access.
For example, the content I was interested in was at:
http://www.pnas.org/content/early/2009/09/18/0909115106.full.pdf+html
by adding the .proxy.lib.pdx.edu to the address, I was able to get the pdf:
http://www.pnas.org.proxy.lib.pdx.edu/content/early/2009/09/18/0909115106.full.pdf+html
even though the option didn't show up from Google Scholar.
and it seems rather odd to me that we could've had a significant population of ancestors that failed to leave a fossil record.
It's not really so odd. First, however, is the assumption that there is a significant population who didn't leave fossils. It's probably more likely that there are fossils and they just haven't been found. The Earth is big and only a small percentage of it has been searched for fossils.
Then you have to consider that not all geologic structures and death conditions are conducive to fossil formation. Go out into a wild area today and count the number of animals you find. Then count the number of somewhat intact carcasses you find. You won't find many. So of the critters out there alive today, only a tiny percentage of them will end up as fossils in another few million years. On top of that, if the places humans like to live today were in similar conditions (near large sources of water, for example), there's a good chance that we've built over any fossils many times over.
I suspect that if you made a Drake-Equation like formula for predicting finding fossils of any particular type that even if many fossils might exist, very few of them would be found. Consider that of the millions of A. afarensis that probably existed, we have only found a handful of their fossils.
So sure, there is a gap, but there's a pretty reasonable explanation for that gap. Until we have exhausted such possibilities, and without startling evidence to the contrary, we can't seriously claim that the gap in the fossil record is caused by divine or extra-terrestrial intervention.
What finally worked for me was to take the relative's computer, fix it, then just keep it for a few weeks before returning it. After doing that a few times nobody came to me any more to fix their computers any more. It helped that my mom would tell people that I've been working a lot lately and just haven't had time to do much else.
Just imagine: math textbooks with problems that you can't just solve right away!
Did you ever get to the end of the textbooks? That's what always bugged me... all the really good stuff was in the back and we never, ever got there.
Now that I'm much older and somewhat wiser, I work the problems in the back on my own now... I wish I'd thought of that 30 years ago... Of course now, most textbooks I use start out pretty interesting and only get harder as you get through them!
no, it was a network that had him as the "caretaker". Despite the methods, from what has been said, what he was doing was trying to protect the network. As a "caretaker", it's his job to do what he must to protect the network.
Actually, all of his authority with respect to this network come from his supervisor/manager. He only has the authority to "do what's best for the network" as long as it's still granted to him by his supervisor. As soon as his supervisor revokes that authority, he no longer has the privilege of deciding what is best for the network.
After all that, he was just being a dick, and it's stupid to be a dick to people who can have you locked up in jail. This may be United States, but it's not the United States you were (probably) taught about in grade school.
Take Conway's game of life, for example. Given a non-trivial starting arrangement, without actually running through all the iterations, can you predict the state the system will stabilize at? Can you even predict (for non-special cases) if it will ever stabilize?
I'm risking a big "whoosh" here, but aren't you simply restating the premise behind the halting problem?
As for The idea is that by starting with something very simple, you can get very complicated behaviour. The problem is, there aren't any proper mathematical tools for predicting that behaviour, except in very simple cases. The best you can do it try it out and see..
I haven't done much directly with CA, but I have dabbled in agent-based simulation. It seems to me you're describing "emergence". But I think it might be at least slightly more useful than string theory. Using ABS, one thing you can try to demonstrate is a "minimum set of rules" needed to generate a certain seemingly complex behavior that has been observed in reality. Having done so doesn't mean that you've actually found the actual rules that drive the behavior of the system, but it serves a good starting point for understanding how that system works.
You seem to think that a tariff increases the efficiency of the Japanese economy. If that's true, then why not double, triple, or quadruple it? By your logic, since the auto industry is a greater benefit to Japan's economy than other possible uses of their money, they should raise the tariff to infinity and reap the rewards.
Do you really live your life thinking so linearly? That if a little is good then more must be better? That if a little is bad then more must be worse?
Most but the simplest of situations involve complex systems with feedback loops and non-linear effects. A very simple example is water consumption. With a total lack of water, you'll die. Drink too much water, and you'll die (hypernatremia). So clearly, you should consume some water, but not too much. By your stated logic, we should all drink as much water as possible because a little is good for us... or we should drink none?
It's the same with protectionism. For the economy as a whole, some protectionism is good. Too much drives inefficiencies and lop-sided economies. Too little and your economy is too easily ravaged by external forces; also leading to unstable economic conditions. Japan was served pretty well by its protectionist policies for its auto sector; as it now dominates the world.
Finally, "economic efficiency" is not necessarily a good ultimate goal for economic policy. Consider that farming is labor-intensive; if we wanted highest efficiency, we'd outsource all of our farming to other countries where the labor is cheap and the soil requires less treatment. I hope you can see the stupidity of an argument for doing so.
But of course, I'm sure laissez-faire is the best overall. That's why we should have football games with no rules and no referees... with each player working towards his own best interest the invisible hand will magically guide them to a perfect game of football.
If you wait long enough, you'll die anyway, so why bother eating and maintaining your health?
Tariffs discourages trade, but it's not true that that hurts everyone. Sure it can be mathematically shown (over a limited range, with linear assumptions, ceteris paribus, and all that) that removing tariffs and quotas lead to more trade. However, that says nothing about the quality of the economic activity or the distribution of the benefits of the trade across the population.
The Japanese car industry is an excellent counter-example to your point. It was carefully protected with tariffs for several decades and it is now one the dominant automobile producers in the world. Having this strong domestic industry does more for Japan's economy as a whole than would having the slightly cheaper cars that the lack of tariffs would have permitted.
producers who decided Americans were too stupid to know what a Newton is.
Of course we know what a Newton is... you just have to decide if you're going to go with one of the newer fruit varieties or to stick with the classic Fig.
(http://en.wikipedia.org/wiki/Fig_Newton)
I love how they change the contract after you have agreed to it.
I think a lot of these anti-consumer contracts have language that says that they can change the terms of the contract. It's strange, like self-modifying code.
I use a cheap, no-contract (no more than month to month) cell phone company (http://www.virginmobile.com/). Sure it comes with a bit of a lame phone (target market is teenagers), but I can dump them today if I want to. I'm amazed at some of my friends who wonder why I don't get a nicer phone "for free" and sign up with one of major carriers. They complain about their crappy broken phone they can't replace (because they're under contract) or the phone bills that have hundred dollar calls from foreign countries that the company won't dismiss and threaten to send collections...
When my $20 phone finally craps out (had it for over a year now.. no problems), I think I'll try these guys: http://www.straighttalk.com/ServicePlans, relatively cheap decent phones and $45/month unlimited everything. Either that or maybe cricket (http://www.mycricket.com/).
I had Verizon once, and they were okay. I suppose if they come out with a decent phone and a $45/month for everything plan (with no contract), I'll think about going back.
One of the nice things about Virgin Mobile is that if something happens to your phone, you can be back up and running in about as much time as it takes you to buy a phone at the store. I was having a party at my house and an hour before people started showing up, I stepped on my phone and broke it. I quickly ran to a local store and had phone service in about 20 minutes; only missed 3 calls asking for directions. I now keep a spare cheapie in case something like that happens again or if an out-of-country guest needs a phone while they're visiting. I just put $20 on it for them and they're good for a while without worrying about international rates.
In most local school districts teachers are no more permitted to use cell phones in class than students. Sure, it would be a minor inconvenience when they have a break, but their classrooms and offices likely already have phones in them.
The problem with this is that most teachers I know (I used to date one) practically live in their classrooms... they are always there, between breaks, during "off hours", during lunch, and before and after class. There's no reason they shouldn't be able to use their phones during those times.
If a kid is distracting itself when it should be learning, that's it's problem (I used to read science books in my lap during social studies). If it's distracting other students with a phone, then you do the same thing you do when it's distracting other students with anything else... take the distraction away, or send the kid away. The teacher I dated would take away cell phones, ipods, etc, and require the parent to come pick them up from the school. If the kid wouldn't give up the item, she's send the kid to the office.
My teachers used intercept any notes passed in class and read them aloud. I see no reason why they can't do that with text messages too.
They are required in all first-world nations, most second-world nations and some developing countries are catching up fast. My point is that you limited specifically to the US, something which Europeans tend not to do in a matter like this.
I think he was actually trying to avoid making sweeping statements about the state of the world as a whole, but instead was talking about what he had direct knowledge of.
I can see how it might have come off that he was implying that the US was superior for requiring catalytic converters, leaving open the question of whether other countries did. But I do not think that was his intent.
I truly think this was a USian trying to be sensitive to the fact that the US is not the world. That's far better than the typical stereotypical American who thinks the way it's done in the US is the only way, or simply assumes that everyone does it the same way.
What a bad burner does? Burn a bad bit?
The problem is that things in the physical world are rarely binary. Sure, an "on" might be the laser bounces back and an "off" is where the laser passes through. But what's the quality of the holes made and what to their boundaries look like. I'm guessing that the light reflected back is never 100% and the light that goes through is never 0%, but rather there are fuzzy boundaries. If the laser that does the burning doesn't do a good job on the boundaries between 1's and 0's then after some degradation in the material, a reading laser might have trouble figuring out if 50% should be a 1 or 0.
There's a simple fix to that (that I'm quite sure is already in place): Simply charge for peak hour usage for industrial uses. Then the aluminum refinement will take place from 9pm-5am.
The aluminum plant where most of my family worked (where Google now has a facility) ran 24 hours/day. It would be too costly to heat things up then let them cool off during the day just to heat them back up again.
Most of these plants are located very close to electricity production (this one is within eye-sight of a hydro-power dam) and most likely use sophisticated financial models to determine the price they end up paying for power.
Well, I'm not as agile as I used to be, so I probably drop 2 or 3 bulbs a year.
However, I'm not convinced that in the complete lifecycle of the products that CFLs are really that much more efficient.
The CFLs appear to have a more complicated manufacturing process with more exotic materials (electronics, mercury).
The consider the packaging. Most CFLs I've seen are encased in that clamshell plastic. That, when coupled with the fact that most of them are larger than their incandescent counterpart, means that it takes a much larger carton, or more cartons, to ship the same number of bulbs. Consider the number of incandescent bulbs that would fill one ship. You'd need at least 2 ships to transport as many CFLs. Plus, with being heavier, they require more energy to transport.
Some of that is probably offset by the claims of longer life when compared to incandescent, but I'm not experiencing that.
On top of all that, I can't use the CFLs on my motion sensing switch, they produce inferior light, and cause a hazmat condition when I drop one (and I worry that my cats will ingest the mercury when they walk over the area and later lick their paws - how can I know I got all of it?)
Don't get me wrong, I'm all about doing things more efficiently, and I even have several CFLs in my house. I'm just not convinced they're as wonderful at saving energy as the industry claims - especially when you consider them with their end-to-end supply chain.
Compare that to the method for incandescent bulbs:
1) sweep broken bulb pieces into adust pan and dump in the garbage
Plus I don't have to turn off my central air each time I clean the floor after that.
The physics you're looking for here is impulse, specifically, the change in p = mv over time. ...
This also happens to be the same reason that you have to follow through on your swing while hitting a baseball or tennis ball or whathaveyou to get the longest distance.
Thanks! The example I thought of first was the PLF (Parachute Landing Fall) where a military paratrooper is supposed to land in such a way that the impact with the ground is spread along the parachutist's body. http://en.wikipedia.org/wiki/Parachute_Landing_Fall It's an easy example from my own life... and when I could actually pull one off, the landing WAS a lot better.
Physics: learn it, use it, benefit from it. (hint: application of kinetic energy would be a starting point to understanding this)
I don't think it's as simple as that.
I'm no physicist but I would suspect that there is a great deal of difference between firing a frozen chicken and a thawed chicken at something. With enough velocity, of course, the differences in outcome will not be very much. But if you give the chickens progressively less velocity at impact, I think you'd find the frozen chickens still penetrate the glass at some levels of kinetic energy where the thawed chickens would not.
My reasoning for this has to do with differences in how the kinetic energy of the chicken is imparted to the windscreen, both through time as well as the area of impact.
The body of frozen chicken will "give" much less than the body of a thawed chicken, so the windscreen has a much shorter period of time to absorb kinetic energy of the chicken. Also, due to that lack of give, the kinetic energy of the chicken's body will be spread over a larger area of the windscreen.
If I drop a 5 kg bag of laundry on my car's windshield from my roof, it will bounce off the windshield and leave it intact. If I drop a 5 kg pipe wrench from the same height, it will most likely shatter the windshield. It's the same idea. With the bag of laundry, the windshield gets more time and more area to absorb the kinetic energy, with the wrench, not as much. Though maybe if I dropped both from a 10 story building, the windshield might not survive it either way.
This isn't simply a matter of an application of equal amounts of kinetic energy. There are a lot of things going on at the point and time of impact that can alter the outcomes... within a certain range of energies.
Last time I checked the air france black box recorder hasn't been located let alone pulled out of the ocean. Without having the black box how can the NTSB be making speculations as to the cause of the downed flight?
Well, considering the NTSB is a part of the US government, it could be in their interest to make speculations that make a foreign plane manufacturer look bad in order to make a domestic manufacturer look more desirable.
Why would you want an iPhone on T-Mobile when you can already get an Android handset?
Why not? Most consumers make only barely rational choices based on a myriad of impulses they are hardly aware of. This person wants an iPhone and wants to use it on T-Mobile. You probably want a different combination. What makes your choice any more or less rational than this persons?
When your math teacher only cares about "feelings" and not objective laws of mathematics, it doesn't matter that he followed his Union leader's instructions to vote for Obama, you'll still get morons coming out of the school system.
Have you ever actually worked with teachers? (not as a student but as a coworker?) They're amazingly strong-headed, stubborn, surly, and resistant to people telling them what to do. Their union might suggest they vote one way or the other, but if anything, they're likely to vote against that just to resist being told what to do.
I was in a job where I ended up in an education union. Really, all it meant was another line in my pay-statement where money was taken out, and a bit of "junk mail". The union certainly never told me how to vote, nor would I have listened or cared if it had.
Are you sure about that? I thought it was:
D = -(d'/ e^(i*pi))