Just for clarity (and to shake my fist at Schoolhouse Rock), if you're going to refer to Edison's DC, then you should refer to Tesla's AC (not Westinghouse's). And the only reason Edison "advocated small power stations all around a municipality" was because that's the only way his baby, DC, would work. DC just doesn't travel well.
To be more precise - it's the low voltage does not travel well (both AC or DC), and in that moment no-one knew how to change DC voltage.
Once they've figured out how to make AC electric motor, Edison's DC system was doomed.
Nowadays, somewhat paradoxically, high voltage DC is even preferred for long distance transmission.
I used to work in four different companies. From my experience, the code will be forgotten for good.
As a first, software products are typically poorly documented. Typically, some documentation is written *after* the project. If project has failed, the chances are that even post-mortem documentation would never be written. Without documentation, there are small chances that someone will be able to use the code.
Technologically speaking, code reusability is generally very low. Except if it is some framework (which by default means that it is for reuse), sometimes even small changes in business logic may lead to significant changes in code (if it affects some assumptions that are made early in project). Different project would probably require too much change.
Even if the same programmer needs to be swapped to the new project, very few code will be taken to it. But he will transfer his experience, which is not a small asset.
I will give you one small example. I had to write a TCP stack simulator. I was contracted to write a TCP over ATM simulation. My plan was to give a code as GPL after the release (no legal problems there). Project started very well, with nice OOP architecture and everything. As project went further, I noticed some errors in design, but it was too late to change them. The closer we were to the deadline, there was more and more bad code inserted. Not that there were many bugs, but it was not that elegant as it was in the beginning. Finally, no matter that simulation worked quite ok, I was not that impressed by idea to give it to the public. Simply, code was in a need of a refactoring; documentation was almost non-existant; I had no time or motif to work on any more.
That project was a success, but would there be any real benefit of giving that code to someone else to use it? Now imagine if that was a failed project - same thing but with bugs and without any results. Who would ever like to use that?
I am quite sure that if the original authors of IP knew in advance what Internet would look like in 2008, they would do some stuff differently. On the other hand, as they had no chance of predicting future, they could only assume what might happen in distant future. If they had tried to implement that, we would probably get some over-engineered system (e.g. something like X-Window) but still in year 2008 our real problems would not be solved. So I am quite ok with their work, thank you very much.
Yes, but you can see them only once you find something in the search. And they used to have some funny system trying to prevent people from printing original scans.
There is an on-line archive of all people that have passed trough Ellis Island (http://www.ellisisland.org/search/passSearch.asp). It consists of retyped (OCR-ed?) ship manifests. Manifests are lists of passengers, with names, places of births and similar information. In original, they are written by hand, in cursive scripts (as expected for late 19th and early 20th century).
Problem is not with the script, but with appropriate context. Someone who retyped this, did not know what to expect in these forms.
My grand-grand father's place of origin was written as "Lipovqani, Slovenia". Pair "lj" was recognized as "q". For someone who is native English speaker "lj" one next to other does not make too much sense. But for anyone with Slavic origin, "q" does not make sense (it's only in foreign words), and "lj" does make sense since it is a way to write "soft l" voice like in "Richelieu".
Ok, maybe that was not the an easy part to guess. But "Slovenia" was serious error. In that moment, Slovenia did not exist. It was part of the Austro-Hungary, and it did not exist as single entity inside it. What was really written was actually "Slavonia". That's an area in Eastern Croatia, and it *was* an entity inside Austro-Hungary.
Should I mention that I was not able to track my grand-grand mother and my other grand-grand father?
A communist from the West decides to move to USSR. He explained to his friends that he would write letters to them. Worried about freedom of mail, he explained them that if he writes anything in red ink, that would mean that reality is opposite from the written.
He moves there, and after a while, the first mail finally arrives. It says: "Everything is great here in USSR. People are happy, wealthy, there is a lot of everything in stores, freedom is enormous. The only problem I have seen here is that you cannot buy any red ink."
I really don't know what is this fuss about lack of IP numbers.
If we already write them as xxx.yyy.zzz.ttt, why we stop at 255? We could simply go up to 999! Even better, we could use the letters too. Imagine all the possibilities if we take separately lower case and upper case!
And finally, when we exhaust these too, we could move to unicode.
I modded you "overrated", hoping that "Score: 1, Overrated" would be even more embarrassing for you.
As it appeared as "Score: 1, Informative", now I feel embarrassed since I am 32 and I still did not get hot Slashdot moderating system works.
If this post does not cancel my moderation, I will just cry.
Re:buy an old S10 and convert it to electric
on
DIY Hybrid Car Kit
·
· Score: 1
Apart from the shell (which is very durable in modern cars, even in the cheap ones), most complicate system that both electric and gas powered car do have is breaking system. Ok, we may say that the air conditioning is more complicate, but it is not an essential part.
Electric car does not have: transmission (reliable part but very expensive if it breaks), it does not have a clutch, it does not have an ICE engine.
Electric car, unlike the ICE one has an electronic device that converts battery voltage to the desired voltage of the engine. This is equivalent of the carburetor or "direct injection" in modern cars. But being an electronic component it does not have any movable part. Being static adds very much to the reliability. And of course, there is an electric motor.
To make this long story short. Less movable parts - better reliability.
As an electric engineer, I would place my bet that electric cars will be significantly easier/cheaper to maintain, but it is very hard to know what the probabilities really would be. Maybe first widely sold models will be poorly built for some totally unrelated reason.
Current electric vehicles - typically trains, trams and forklifts - are built as extremely robust, so it is very hard to compare them to cars.
US grid has extremely low capacity in high-voltage lines. Any decently run power company would never allow that. But that is long term investment (lines and transformers last 40+ years) and no-one wants to put money there, esp. for some exotic feature called "redundancy". Last black-out in NYC (2003) was due to lack of redundancy in high-voltage lines.
I would say that this is a turn back to original "10% of features that 90% of users really use".
Is there any point of having all these features implemented when you know that most of your userbase will be never actually use it? MySQL was small, easy to use and fast. I agree that it would be nice every web app to use advanced features that would probably give us less pain with SQL insertions and similar, but let's face it - 90% of web developers have to concentrate on GUI and middle tier (if it exist at all), they don't have time to spend on DB.
Even more, even if you have clear multitier architecture, it usually means that you have an explicit ORM, which means that you work easily with objects and that you don't have to bother too much with the DB. As a result, most of the logic will go to the middle tier (business logic) not to the DB, since you actually don't see the DB any more.
Well, just imagine if we hadn't interfered in Iraq, Afghanistan in the 60s, Vietnam, Korea, etc.
(emphasize is mine) Then instead of rich and (now) democratic South Korea and poor tyrannic North Korea, we would have poor tyrannic Korea across entire peninsula. And even more likely, passivity from the West would probably encourage Soviet Union and its satellites to try to attack even more countries.
Routers are complicated devices. There's a lot of software inside it and it is not a surprise that they get stuck. It is surprise that they don't have some system to reboot themselves, as it is very simple to implement.
My company made routers for our own needs (never sold to wide market). They were Soekris based, with custom Linux distro inside. We had some issues with one wireless driver, so there was a script that monitored wlan interface to see if everything was ok. If there was a problem (in our case, we had known that wlan0 would disappear if driver had failed), script would reboot the device.
It is simple to write such script if you "hunt" for the known specific problem, like we did. But it is reasonably simple to make some small monitoring program that will try to see if everything goes right. Maybe it won't catch 100% of problems, but you can always do at least something.
Real problem is when whole system goes to a freeze. But that is even more easy to solve. Many microcontrollers have "watchdog timer". if the software does not periodically do some required operation with the timer, after predefined time it would reset the controller. Not a perfect solution, but still better than frozen hardware. I think that it would be trivial to add such hardware to routers.
I guess that CEO did quite good demonstration but the journalist did not get everything right. No smoke - that's ok and experiment proves that. No heat - that's rubbish, of course there was heat - experiment proved that. Efficient burning means that almost all amount really burns. You may think that every fuel does so, but it is not the truth. Coal for instance, does not burn fully. Gasoline is better, but there are still some unburned hydrocarbons. LNG is way better than gasoline, since almost everything goes to either C02 or water. "No smoke" means no visible smoke. You cannot see C02 nor water vapor. The more pure is the fuel, it burns better. Buy some gasoline from a pharmacy (they sell it for some reason), it burns perfectly. But what we buy as gasoline at the pump station is actually a mixture of many different hydrocarbons, and it does not burn so well.
Long story short, if they are able to produce fuel without heavy hydrocarbons, aromatic hydrocarbons etc, it will burn almost 100%, without smell (i.e. unburned hydrocarbons) and without trace (again, unburned hydrocarbons).
If I were you, I would not boycott it. The company is very innovative, and it does a very good job to USA economy.
I believe that our company does not do the outsourcing in "bad way". If there was no outsourcing, this company would never existed, as they had so small amount of money when they started, that they simply needed to do the initial job somewhere cheaply.
After that, company had an exponential growth. As a result, it employed 60 people in USA. From 1:1 ratio of employees in USA compared to Serbia, it is now 3:1, and the best jobs are in USA. I firmly believe that this was a benefit for USA's economy.
(And quite surprisingly, all hardware is done by a contractor in USA.)
It seems that I am on the other side of the story (dark side?) since I actually work in an outsourcing company. I work in Serbia, and we provide some programming for one company in USA.
It may be that we are not a typical example, but in our case there are about 60 employees in USA and 20 here in Serbia.
Complete R&D, marketing, and all top-jobs in IT are done in USA. Here in Serbia we do very basic tasks only.
In our particular case, we are not doing the job very well. Successful outsourcing requires very good communication channels. Due to geographical difference and esp. if there is time zone difference (like USA - India) communication must be perfect. This is very hard to achieve. That would require trained people in USA to write good specs, to know how to handle tasks and everything. For a beginning, just to know what they want as a product. In practice, that would mean that good managers will do some good work and bad managers will do some bad work, just as if there was no outsourcing. Outsourcing will just make existing communication problems bigger.
In our particular case, since we work in extremely regulated industry, things are even harder. Everything in the process has to be double-checked, documented and so on. In theory, this makes things more easy to outsource, but in practice, as major job has to be done in USA, outsourcing does not seem too beneficial. In our case, only thing you can outsource are junior jobs. But they have problems figuring this, and they try over and over to send us any tasks they find "labor intensive". This won't work. Outsourcing company is not a cavalry you call when you are in trouble. If you want to treat it like a cheap labor for boring tasks, you'll be in a huge problem.
As a complete surprise to a geniuses who believe that outsourcing is a solution for poor business practices, people that work in outsourcing companies are human, too. When treated as junk, they treat their employers as junk, so they tend to leave for small increases in salaries, since their job satisfaction is low and salary in only measure. Even more surprisingly, if treated as humans, outsources tend to behave just every normal employee. They learn about their jobs, they are ready to spend some time there when salaries are not the highest in the city and so on.
It's a bit different story when large company, like HP decides to outsource entire department. I don't see how this could be efficient. It's not a problem to replace junior John Doe with Asok in Delhi, but if you need to replace every trained team-leader, every mid-manager with the Indian counter-part, it seems to me like a recipe for disaster.
Why not just insert your ad to the popular user's profile without asking him? Or even better, why not insert ad to every profile page no matter if it is from the popular user or not? Or even even better, why we don't insert ad on every single page on the site? Oh, wait, it's the way Internet works for decades.
Well kinda sorta he had a function h valid for integers, and he wanted it to be valid for all rational numbers, so he just defined it as 0 everywhere else.
I remember the example from my university math class about function defined in exactly that way. The question was if it is possible to calculate an integral of the function. The conclusion was that it is impossible, because of something I forgot, but it is related to definition of the integral, which requires some very basic kind of continuity and this function lacks such feature. (I guess that some limes must exist, and it does not exist here as it always go 1 to 0 unpredictably.)
Then he took a continuous and not a discrete Fourier transform of the resulting function, maybe getting an infinite series of coefficients that diverge. Of course keep in mind that I'm just talking out of my ass.
Since the definition of Fourier transform requires integration, I guess that it might be the problem.
But on the other side, proof that mentioned function was not possible to integrate did not use those strange words as this professor does.
Slashdot Mirror
Just for clarity (and to shake my fist at Schoolhouse Rock), if you're going to refer to Edison's DC, then you should refer to Tesla's AC (not Westinghouse's). And the only reason Edison "advocated small power stations all around a municipality" was because that's the only way his baby, DC, would work. DC just doesn't travel well.
To be more precise - it's the low voltage does not travel well (both AC or DC), and in that moment no-one knew how to change DC voltage.
Once they've figured out how to make AC electric motor, Edison's DC system was doomed.
Nowadays, somewhat paradoxically, high voltage DC is even preferred for long distance transmission.
Vermont's motto is "Freedom and unity".
This way they deliver "unity" - all mail web-services under one, united interface.
Also you get freedom from non-Fairpoint advertisements.
Market success of such "medicaments" is proof that free market is essentially a myth.
I used to work in four different companies. From my experience, the code will be forgotten for good.
As a first, software products are typically poorly documented. Typically, some documentation is written *after* the project. If project has failed, the chances are that even post-mortem documentation would never be written. Without documentation, there are small chances that someone will be able to use the code.
Technologically speaking, code reusability is generally very low. Except if it is some framework (which by default means that it is for reuse), sometimes even small changes in business logic may lead to significant changes in code (if it affects some assumptions that are made early in project). Different project would probably require too much change.
Even if the same programmer needs to be swapped to the new project, very few code will be taken to it. But he will transfer his experience, which is not a small asset.
I will give you one small example. I had to write a TCP stack simulator. I was contracted to write a TCP over ATM simulation. My plan was to give a code as GPL after the release (no legal problems there). Project started very well, with nice OOP architecture and everything. As project went further, I noticed some errors in design, but it was too late to change them. The closer we were to the deadline, there was more and more bad code inserted. Not that there were many bugs, but it was not that elegant as it was in the beginning. Finally, no matter that simulation worked quite ok, I was not that impressed by idea to give it to the public. Simply, code was in a need of a refactoring; documentation was almost non-existant; I had no time or motif to work on any more.
That project was a success, but would there be any real benefit of giving that code to someone else to use it? Now imagine if that was a failed project - same thing but with bugs and without any results. Who would ever like to use that?
I am quite sure that if the original authors of IP knew in advance what Internet would look like in 2008, they would do some stuff differently. On the other hand, as they had no chance of predicting future, they could only assume what might happen in distant future. If they had tried to implement that, we would probably get some over-engineered system (e.g. something like X-Window) but still in year 2008 our real problems would not be solved. So I am quite ok with their work, thank you very much.
Geez, this was a good one (from linked FA):
MWe can disconfirm that expert systems can be made amphibious, highly-available, and linear-time."
ZAO means "Zakrytoye Aktsionernoye Obschestvo" (Privatly Held Corporation) in Russian, it's not a part of the name.
Funny thing is that "zao" is adjective meaning "evil" in Serbian.
Maybe NVIDIA needs to have a chat with NASA about quality assurance.
I hope NVIDIA won't start producing O-rings any time soon.
Yes, but you can see them only once you find something in the search. And they used to have some funny system trying to prevent people from printing original scans.
There is an on-line archive of all people that have passed trough Ellis Island (http://www.ellisisland.org/search/passSearch.asp). It consists of retyped (OCR-ed?) ship manifests. Manifests are lists of passengers, with names, places of births and similar information. In original, they are written by hand, in cursive scripts (as expected for late 19th and early 20th century).
Problem is not with the script, but with appropriate context. Someone who retyped this, did not know what to expect in these forms.
My grand-grand father's place of origin was written as "Lipovqani, Slovenia". Pair "lj" was recognized as "q". For someone who is native English speaker "lj" one next to other does not make too much sense. But for anyone with Slavic origin, "q" does not make sense (it's only in foreign words), and "lj" does make sense since it is a way to write "soft l" voice like in "Richelieu".
Ok, maybe that was not the an easy part to guess. But "Slovenia" was serious error. In that moment, Slovenia did not exist. It was part of the Austro-Hungary, and it did not exist as single entity inside it. What was really written was actually "Slavonia". That's an area in Eastern Croatia, and it *was* an entity inside Austro-Hungary.
Should I mention that I was not able to track my grand-grand mother and my other grand-grand father?
A communist from the West decides to move to USSR. He explained to his friends that he would write letters to them. Worried about freedom of mail, he explained them that if he writes anything in red ink, that would mean that reality is opposite from the written.
He moves there, and after a while, the first mail finally arrives. It says: "Everything is great here in USSR. People are happy, wealthy, there is a lot of everything in stores, freedom is enormous. The only problem I have seen here is that you cannot buy any red ink."
I really don't know what is this fuss about lack of IP numbers.
If we already write them as xxx.yyy.zzz.ttt, why we stop at 255? We could simply go up to 999! Even better, we could use the letters too. Imagine all the possibilities if we take separately lower case and upper case!
And finally, when we exhaust these too, we could move to unicode.
I modded you "overrated", hoping that
"Score: 1, Overrated" would be even more embarrassing for you.
As it appeared as "Score: 1, Informative", now I feel embarrassed since I am 32 and I still did not get hot Slashdot moderating system works.
If this post does not cancel my moderation, I will just cry.
Apart from the shell (which is very durable in modern cars, even in the cheap ones), most complicate system that both electric and gas powered car do have is breaking system. Ok, we may say that the air conditioning is more complicate, but it is not an essential part.
Electric car does not have: transmission (reliable part but very expensive if it breaks), it does not have a clutch, it does not have an ICE engine.
Electric car, unlike the ICE one has an electronic device that converts battery voltage to the desired voltage of the engine. This is equivalent of the carburetor or "direct injection" in modern cars. But being an electronic component it does not have any movable part. Being static adds very much to the reliability. And of course, there is an electric motor.
To make this long story short. Less movable parts - better reliability.
As an electric engineer, I would place my bet that electric cars will be significantly easier/cheaper to maintain, but it is very hard to know what the probabilities really would be. Maybe first widely sold models will be poorly built for some totally unrelated reason.
Current electric vehicles - typically trains, trams and forklifts - are built as extremely robust, so it is very hard to compare them to cars.
US grid has extremely low capacity in high-voltage lines. Any decently run power company would never allow that. But that is long term investment (lines and transformers last 40+ years) and no-one wants to put money there, esp. for some exotic feature called "redundancy". Last black-out in NYC (2003) was due to lack of redundancy in high-voltage lines.
Just because its in the contract doesn't make it legal.
Just because it's legal it does not mean you can enforce it.
I patented the ability to talk about patent news stories in a threaded manner. Pay up suckers.
According to TFA, I can mod you "overrated" now!
I would say that this is a turn back to original "10% of features that 90% of users really use".
Is there any point of having all these features implemented when you know that most of your userbase will be never actually use it? MySQL was small, easy to use and fast. I agree that it would be nice every web app to use advanced features that would probably give us less pain with SQL insertions and similar, but let's face it - 90% of web developers have to concentrate on GUI and middle tier (if it exist at all), they don't have time to spend on DB.
Even more, even if you have clear multitier architecture, it usually means that you have an explicit ORM, which means that you work easily with objects and that you don't have to bother too much with the DB. As a result, most of the logic will go to the middle tier (business logic) not to the DB, since you actually don't see the DB any more.
Well, just imagine if we hadn't interfered in Iraq, Afghanistan in the 60s, Vietnam, Korea, etc.
(emphasize is mine)
Then instead of rich and (now) democratic South Korea and poor tyrannic North Korea, we would have poor tyrannic Korea across entire peninsula. And even more likely, passivity from the West would probably encourage Soviet Union and its satellites to try to attack even more countries.
Routers are complicated devices. There's a lot of software inside it and it is not a surprise that they get stuck. It is surprise that they don't have some system to reboot themselves, as it is very simple to implement.
My company made routers for our own needs (never sold to wide market). They were Soekris based, with custom Linux distro inside. We had some issues with one wireless driver, so there was a script that monitored wlan interface to see if everything was ok. If there was a problem (in our case, we had known that wlan0 would disappear if driver had failed), script would reboot the device.
It is simple to write such script if you "hunt" for the known specific problem, like we did. But it is reasonably simple to make some small monitoring program that will try to see if everything goes right. Maybe it won't catch 100% of problems, but you can always do at least something.
Real problem is when whole system goes to a freeze. But that is even more easy to solve. Many microcontrollers have "watchdog timer". if the software does not periodically do some required operation with the timer, after predefined time it would reset the controller. Not a perfect solution, but still better than frozen hardware. I think that it would be trivial to add such hardware to routers.
I guess that CEO did quite good demonstration but the journalist did not get everything right. No smoke - that's ok and experiment proves that. No heat - that's rubbish, of course there was heat - experiment proved that. Efficient burning means that almost all amount really burns. You may think that every fuel does so, but it is not the truth. Coal for instance, does not burn fully. Gasoline is better, but there are still some unburned hydrocarbons. LNG is way better than gasoline, since almost everything goes to either C02 or water. "No smoke" means no visible smoke. You cannot see C02 nor water vapor. The more pure is the fuel, it burns better. Buy some gasoline from a pharmacy (they sell it for some reason), it burns perfectly. But what we buy as gasoline at the pump station is actually a mixture of many different hydrocarbons, and it does not burn so well.
Long story short, if they are able to produce fuel without heavy hydrocarbons, aromatic hydrocarbons etc, it will burn almost 100%, without smell (i.e. unburned hydrocarbons) and without trace (again, unburned hydrocarbons).
If I were you, I would not boycott it. The company is very innovative, and it does a very good job to USA economy.
I believe that our company does not do the outsourcing in "bad way". If there was no outsourcing, this company would never existed, as they had so small amount of money when they started, that they simply needed to do the initial job somewhere cheaply.
After that, company had an exponential growth. As a result, it employed 60 people in USA. From 1:1 ratio of employees in USA compared to Serbia, it is now 3:1, and the best jobs are in USA. I firmly believe that this was a benefit for USA's economy.
(And quite surprisingly, all hardware is done by a contractor in USA.)
It seems that I am on the other side of the story (dark side?) since I actually work in an outsourcing company. I work in Serbia, and we provide some programming for one company in USA.
It may be that we are not a typical example, but in our case there are about 60 employees in USA and 20 here in Serbia.
Complete R&D, marketing, and all top-jobs in IT are done in USA. Here in Serbia we do very basic tasks only.
In our particular case, we are not doing the job very well. Successful outsourcing requires very good communication channels. Due to geographical difference and esp. if there is time zone difference (like USA - India) communication must be perfect. This is very hard to achieve. That would require trained people in USA to write good specs, to know how to handle tasks and everything. For a beginning, just to know what they want as a product. In practice, that would mean that good managers will do some good work and bad managers will do some bad work, just as if there was no outsourcing. Outsourcing will just make existing communication problems bigger.
In our particular case, since we work in extremely regulated industry, things are even harder. Everything in the process has to be double-checked, documented and so on. In theory, this makes things more easy to outsource, but in practice, as major job has to be done in USA, outsourcing does not seem too beneficial. In our case, only thing you can outsource are junior jobs. But they have problems figuring this, and they try over and over to send us any tasks they find "labor intensive". This won't work. Outsourcing company is not a cavalry you call when you are in trouble. If you want to treat it like a cheap labor for boring tasks, you'll be in a huge problem.
As a complete surprise to a geniuses who believe that outsourcing is a solution for poor business practices, people that work in outsourcing companies are human, too. When treated as junk, they treat their employers as junk, so they tend to leave for small increases in salaries, since their job satisfaction is low and salary in only measure. Even more surprisingly, if treated as humans, outsources tend to behave just every normal employee. They learn about their jobs, they are ready to spend some time there when salaries are not the highest in the city and so on.
It's a bit different story when large company, like HP decides to outsource entire department. I don't see how this could be efficient. It's not a problem to replace junior John Doe with Asok in Delhi, but if you need to replace every trained team-leader, every mid-manager with the Indian counter-part, it seems to me like a recipe for disaster.
Why not just insert your ad to the popular user's profile without asking him? Or even better, why not insert ad to every profile page no matter if it is from the popular user or not? Or even even better, why we don't insert ad on every single page on the site? Oh, wait, it's the way Internet works for decades.
Well kinda sorta he had a function h valid for integers, and he wanted it to be valid for all rational numbers, so he just defined it as 0 everywhere else.
I remember the example from my university math class about function defined in exactly that way. The question was if it is possible to calculate an integral of the function. The conclusion was that it is impossible, because of something I forgot, but it is related to definition of the integral, which requires some very basic kind of continuity and this function lacks such feature. (I guess that some limes must exist, and it does not exist here as it always go 1 to 0 unpredictably.)
Then he took a continuous and not a discrete Fourier transform of the resulting function, maybe getting an infinite series of coefficients that diverge. Of course keep in mind that I'm just talking out of my ass.
Since the definition of Fourier transform requires integration, I guess that it might be the problem.
But on the other side, proof that mentioned function was not possible to integrate did not use those strange words as this professor does.