I don't think I know anybody actively developing outdated professional skills, either... but I can think of several of my colleagues who are actively maintaining skills that are falling out of use. A large portion of Slashdotters, for example, outright refuse to learn about the new-fangled NoSQL technologies, claiming that the traditional RDBMS is absolutely superior. True or not, that's a set of jobs they're missing out on, as more established and start-up companies turn to a business model based around gathering messy data and distilling meaningful statistics for sale. Even when someone does learn a new skill, they'll often leave the old one on their resume, to show off all the great skills they have.
In contrast, in countries with less-established tech industries, the outdated skills simply aren't present. The foreign candidate is less likely to be stuck in old bad habits or using paradigms that don't fit with the new project. That leads to the pigeonholing, as managers try to find candidates with all of the desired skills, but without the risk of extras.
what happens when we graduate STEM people and they can't secure meaningful employment?... Also, if there are no junior-level jobs (that allow for growth), why would one want to go into STEM in the first place?
I'm not sure what you're saying here, but you seem to be implying that employers should hire American workers because if they don't, then they won't be able to hire Americans in the future.
That wouldn't be a problem, because the companies could hire foreigners, just as they do today. In fact, with other countries developing their technology further, the foreign candidate pool will be growing much faster than American labor, so there's little incentive to spend extra time and money investing in American labor now. It's a tragedy of the commons.
It's connected by the oft-used justification for hiring foreigners: the American workforce isn't qualified to meet the business needs.
The assumption is that if you're hiring a foreign tech worker, it's because the existing STEM programs didn't produce an American to fill your needs, so more funding should be sent to STEM programs to make better candidates in the future.
or willing to wait the three months it will take to get them up to speed.
If I were an employer, why the hell should I pay someone $15k for three months of "getting up to speed", when I could bring in a guy from India who can start being productive now, because he's spent the last three months of his own time becoming an expert in the new up-and-coming buzzword technology this project will be using, while the American candidate was brushing up on his old COBOL skills, because he knows that will give him "job security" just as soon as he can find a job that needs it?
Hauling in people from other countries who are no better than the ones here is just an excuse.
If the foreign worker can be ready to go now, that's "better". If the foreigner has been focusing on skills for a new career on the other side of the planet, rather than just continuing an old career with a new company, that could be "better". If the foreigner won't be demanding a raise every time he learns a new skill, because his education didn't teach him that his pay must reflect his skills more than a complex economic balance, that's "better", too.
Of course, if I were an employer, I couldn't actually say publicly that Americans are too self-centered to fit the job. I'd go with some PR-approved line like "the foreign candidate was better qualified", even though it'll piss off the highly-educated American COBOL specialist..
It sounds like Code.org is pushing to have H-1B visa fees earmarked for education programs, rather than just going to general funds.
I skimmed through TFAs (poorly-organized as they were), and I didn't see anything implying they want more H-1Bs. Rather, the most I saw was implying that there could be an increase in H-1Bs, so it would make sense if that increase also increased STEM funding so we don't need H-1Bs in the future.
So let me get this straight... Code.org wants to tie H-1B visa fees to education programs, and somehow that's twisted into the headline saying they want more H-1Bs?
It sounds more to me like they're saying "if you're going to bring in a foreign tech worker because Americans aren't good enough, you're going to pay for American STEM programs so Americans are good enough in the future". I can't really object to that idea.
The defense for everyone convicted of a crime was irrelevant, as they were still found guilty.
Therefore, every defense lawyer who has ever lost a case was clearly conspiring with the prosecutor. Conversely, every prosecutor who has ever lost a case must have been conspiring with the defense attorneys, because his prosecution was irrelevant.
Unfortunately, communism requires the government to be effective at distributing resources in a manner that the people consider to be fair, and there must also be an effective mechanism for ensuring that distribution goes according to plan. Those two criteria have been at the heart of communism's repeated failures through the 20th century. Either the government is highly corrupt and distributes unfairly, or the government orders a fair distribution that never happens because local aggressors disrupt transportation.
The latter problem can be solved by the use of automated delivery systems, but they'd have to be widespread and robust enough to work around any local disruption. The fair-governance problem, on the other hand, I expect to be the greatest accomplishment of AI, and it won't happen any time soon. It's not as simple as dividing all resources evenly, but rather dividing according to what people need to be happy. That's a problem humans haven't figured out yet, let alone designed an AI for it.
A high school student I know got drunk, drove, and killed a fellow student when he decided that a living room would make a good parking spot. His public defender worked him to a five-year probation sentence and a few hundred hours of community service, as I recall.
"Affluenza" is indeed a problem, but despite the claims of the grieving father, I don't see it being a major factor in this case. Penalties for juveniles are lighter out of mercy, regardless of socioeconomic status. Where this kid's family may have helped is in convincing the judge that a trip to a rehab center (on their half-million-dollar dime) is better for society than a trip to jail.
The teenager who got drunk wasn't mature enough to be aware of the severity of his actions. That's why we have a juvenile system in the first place. Even if, while sober, he intended to get drunk and drive recklessly, he probably couldn't understand the risk involved. That's why his sentence is only 10 years' probation rather that jail time. It's a sentence that fits reasonably well with several counts of accidental manslaughter and a DWI.
On the other hand, Sabu indeed clearly set out to cause harm to others. Granted he may have considered it a noble cause, but that's beside the point. Crimes committed in the name of vigilantism are still crimes, and Sabu was mature enough to know the ramifications of his actions.
Probably. It's an ICANN ruling, so as far as I can tell it applies to all ICANN registrars.
What doesn't apply worldwide is the "court order". If an American court tries to issue a court order for a Chinese registrar to hold a name, the Chinese company is probably not required to follow the order, so per ICANN they'd have to release the name. On the other hand, a Chinese order would have jurisdiction, so the registrar would be able (and likely required) to hold the name.
If today $1 buys you one hotdog and your salary is $10/hour, yet a year from now $1 buys you two hotdogs yet your salary is $7.50/hour, your salary has gone "down"
What exactly is the rate of deflation in this example? The price of a hot dog dropped 50%, but the price of labor dropped only 25%.
and the prices are all halved, the result isn't a poorer economy - it's an economy in which everybody can buy twice as much stuff as before.
Nope. The price of labor must also be halved, so everybody can buy exactly what they could before.
Savings are what drive investments - an investment is basically taking a bunch of savings and applying it with the hope of making more money.
Investment is spending any asset toward creating a system to return more value than what was spent. Investing is not saving. When you buy into an investment, you do not keep ownership of your money. You buy a certificate saying you contributed a certain percentage to the endeavor.
You don't seem to understand what the point of commerce is. The whole reason commerce ever happens is to give people things they want. If I want a good, a functional economy should ensure that I have the resources to acquire that good. In a strong economy, everybody can get what they want easily - supply meets demand. The numbers on the currency don't matter at all for that purpose.
Unfortunately, humans don't think that way. They see the numbers and remember what numbers used to be. They predict where the numbers will be in the future, and they adjust habits based on that. with an increased demand for money, there is less money available to the people who want money in exchange for their products, including those who want to sell their labor directly. If labor costs stay perfectly in sync with the deflation, everything is fine, except workers will see the numbers on their paycheck continually decrease, so they'll cut spending even more, until they only purchase bare essentials for life. Yes, they could purchase the same amount as before, but they won't realize that when they're just seeing ever-smaller numbers in front of them.
Without people buying those nonessential goods, the companies making those goods will collapse, leaving those workers jobless (and even faster if wages deflate more slowly than the price of consumer goods). Those unemployed people see even smaller budgets for purchases, continuing the cycle. Eventually there is an equilibrium at the point of desperation, where people can produce just enough for themselves to survive, and all nonessential commerce is effectively halted. Excess production is pointless, because people won't spend the money to buy it.
That's what interest is for. Ideally, the (numeric) amount you owe rises along with the (numeric) amount the lender lost by letting you use their assets for the duration of the loan. In a perfect zero-sum deal, a borrower could take out a loan, invest the cash with inflation-only return, then repay their whole debt with no net transfer of value.
In practice, the interest rate also includes a factor for the lender's assumed risk that you'll default, and a factor for overhead costs, but the bulk of the interest is still covering inflation.
What I want to know is, Why does Ford need this data?
As you noted, many people want their cars to have GPS functionality, and mechanics can benefit from a performance log, and some folks want their car to also be a cell phone, and remember recent radio stations, and so on. There's data storage to support the functions that the car's owners want, and if Ford actually wanted to get that data, they probably could. Either they could have the car transmit data through the cellular network, or just wait for it to come in for maintenance.
I read TFS as being a flippant and sarcastic remark highlighting how mundane data collection actually is. The same data the car could use to tune its performance could also be used to track the vehicle's whereabouts, but that would require Ford having any interest in the car's whereabouts. They're probably more interested in the performance data.
As a related analogy, I used to work in the medical data industry. My job was gathering private medical data. We had full access to medical records for a few million patients (including my wife and coworkers). The first thing we did with that data was wipe out the names and street address information, because they weren't important for our goal. Step two was to hash the unique patient ID number, which we needed to remain unique, but didn't care what it was. Finally, after various routes through statistical analysis, all of the numbers we produced were randomly fudged a little bit to make reidentification more difficult. The bottom line is that we had enough access to tons of highly-sensitive personal information to cause all sorts of trouble... but we just didn't care to do so.
Top line is perfect nuclear fuel. Bottom line is like smelted steel. What's in the middle, though? What material characteristics can be expected in a half-melted core?
Sounds like there's enough oxygen left to go boom.
Question for everyone: does anyone know if Fukushima has the US style concrete containment buildings?
I'm not terribly familiar with the details of reactor design, but I believe you're referring to the outer containment vessel of a pressurized water reactor, which is designed mainly to protect against leaks of steam from the high-pressure cooling lines that come out of the main reactor vessel. In comparison, the Fukushima Daiichi reactors are boiling water reactors, which are smaller by design. Their containment vessel is small enough that it fits inside more normal-looking buildings.
in order to build safe containment vessel floors that can hold an ugly puddle of radioactive sludge.
So we did build such containment vessels? Then why did the Fukushima accident happen at all?
Floors are generally not considered "safe" based on their ability to contain an explosion, and per the subject of discussion, the only criteria I am referring to is indeed the ability to mitigate one particular kind of failure mode. If we expect a single mechanism to protect against every possible failure happening at once, we must also avoid all useful definitions of the words "safe". It's a block of concrete we're talking about, not Superman.
Engineers have been doing failure analysis on nuclear reactors since before sustained reactors were even considered feasible. Almost all individual failure modes are indeed accounted for and are perfectly within the equipment's capabilities to handle, and there are backups and failsafe mechanisms in place to further contain other problems.
The Fukushima Daiichi disaster was a product of multiple failures occurring simultaneously in combinations that were not foreseen in the failure analysis. It was expected that if the facility were damaged, it could be repaired within hours enough to get regular cooling systems operational, and it was expected that the emergency cooling systems would function during that time. Instead, the emergency systems did not perform as expected, backups were offline, and the whole facility was electrically isolated for over a week. That's why the Fukushima Daiichi disaster happened. The floor did its job admirably.
Fukushima's containment vessel could (and did) contain the molten core... but not the hydrogen explosions that also occurred inside the reactor chamber because of the total coolant loss.
My language should imply that nuclear reactors are safe against the foreseen failure modes. At Fukushima Daiichi, it was not expected that all of the coolant systems would fail at once and that repairs would be hampered by the tsunami damage.
Testing failure modes doesn't necessarily imply that the failure modes must be well-understood.
We know that, in a worst-case scenario, reactors can melt down into an ugly puddle of radioactive detritus. We don't understand the mechanics involved, and we didn't really need to in order to build safe containment vessel floors that can hold an ugly puddle of radioactive sludge.
Reaction rates are fairly well understood, as are the characteristics of the radiation itself, so it's fairly straightforward to build a containment vessel that can hold the whole experiment. As I understand it, what's not really well known is how the fuel itself behaves in a meltdown, because they are (fortunately) so rare. Apart from "everything melts and settles in a puddle at the bottom", we don't know how quickly it melts, how that affects reaction rates (though we know it doesn't explode like a nuclear bomb), or if there's any quirks (like hot or cool spots).
The baseline is the starting configuration, which they're building. The worst-reasonable-case scenario is easy enough to figure out, and protection can be built against that. It's the middle area that we don't understand.
And, it should be noted, they want to find out in controlled conditions with sufficient protective equipment in a facility explicitly configured for this kind of situation. This is science.
Ah, yes, because the unmanned probes are doing such a great job on the experiments where humans are the test subjects. At least those probes, carrying a dozen experiments each, are getting a lot of science done. After all, the ISS crew isn't busy or anything, right?
Slashdot Mirror
No one I know are developing out of date skills.
I don't think I know anybody actively developing outdated professional skills, either... but I can think of several of my colleagues who are actively maintaining skills that are falling out of use. A large portion of Slashdotters, for example, outright refuse to learn about the new-fangled NoSQL technologies, claiming that the traditional RDBMS is absolutely superior. True or not, that's a set of jobs they're missing out on, as more established and start-up companies turn to a business model based around gathering messy data and distilling meaningful statistics for sale. Even when someone does learn a new skill, they'll often leave the old one on their resume, to show off all the great skills they have.
In contrast, in countries with less-established tech industries, the outdated skills simply aren't present. The foreign candidate is less likely to be stuck in old bad habits or using paradigms that don't fit with the new project. That leads to the pigeonholing, as managers try to find candidates with all of the desired skills, but without the risk of extras.
what happens when we graduate STEM people and they can't secure meaningful employment? ... Also, if there are no junior-level jobs (that allow for growth), why would one want to go into STEM in the first place?
I'm not sure what you're saying here, but you seem to be implying that employers should hire American workers because if they don't, then they won't be able to hire Americans in the future.
That wouldn't be a problem, because the companies could hire foreigners, just as they do today. In fact, with other countries developing their technology further, the foreign candidate pool will be growing much faster than American labor, so there's little incentive to spend extra time and money investing in American labor now. It's a tragedy of the commons.
It's connected by the oft-used justification for hiring foreigners: the American workforce isn't qualified to meet the business needs.
The assumption is that if you're hiring a foreign tech worker, it's because the existing STEM programs didn't produce an American to fill your needs, so more funding should be sent to STEM programs to make better candidates in the future.
or willing to wait the three months it will take to get them up to speed.
If I were an employer, why the hell should I pay someone $15k for three months of "getting up to speed", when I could bring in a guy from India who can start being productive now, because he's spent the last three months of his own time becoming an expert in the new up-and-coming buzzword technology this project will be using, while the American candidate was brushing up on his old COBOL skills, because he knows that will give him "job security" just as soon as he can find a job that needs it?
Hauling in people from other countries who are no better than the ones here is just an excuse.
If the foreign worker can be ready to go now, that's "better". If the foreigner has been focusing on skills for a new career on the other side of the planet, rather than just continuing an old career with a new company, that could be "better". If the foreigner won't be demanding a raise every time he learns a new skill, because his education didn't teach him that his pay must reflect his skills more than a complex economic balance, that's "better", too.
Of course, if I were an employer, I couldn't actually say publicly that Americans are too self-centered to fit the job. I'd go with some PR-approved line like "the foreign candidate was better qualified", even though it'll piss off the highly-educated American COBOL specialist. .
Stop reading Slashdot headlines.
It sounds like Code.org is pushing to have H-1B visa fees earmarked for education programs, rather than just going to general funds.
I skimmed through TFAs (poorly-organized as they were), and I didn't see anything implying they want more H-1Bs. Rather, the most I saw was implying that there could be an increase in H-1Bs, so it would make sense if that increase also increased STEM funding so we don't need H-1Bs in the future.
So let me get this straight... Code.org wants to tie H-1B visa fees to education programs, and somehow that's twisted into the headline saying they want more H-1Bs?
It sounds more to me like they're saying "if you're going to bring in a foreign tech worker because Americans aren't good enough, you're going to pay for American STEM programs so Americans are good enough in the future". I can't really object to that idea.
The defense for everyone convicted of a crime was irrelevant, as they were still found guilty.
Therefore, every defense lawyer who has ever lost a case was clearly conspiring with the prosecutor. Conversely, every prosecutor who has ever lost a case must have been conspiring with the defense attorneys, because his prosecution was irrelevant.
Everybody's conspiring with everybody except me.
I'm willing.
Unfortunately, communism requires the government to be effective at distributing resources in a manner that the people consider to be fair, and there must also be an effective mechanism for ensuring that distribution goes according to plan. Those two criteria have been at the heart of communism's repeated failures through the 20th century. Either the government is highly corrupt and distributes unfairly, or the government orders a fair distribution that never happens because local aggressors disrupt transportation.
The latter problem can be solved by the use of automated delivery systems, but they'd have to be widespread and robust enough to work around any local disruption. The fair-governance problem, on the other hand, I expect to be the greatest accomplishment of AI, and it won't happen any time soon. It's not as simple as dividing all resources evenly, but rather dividing according to what people need to be happy. That's a problem humans haven't figured out yet, let alone designed an AI for it.
With 100% of your needs being fulfilled by robots who don't need payment, you also will have zero expenses.
Perhaps there is a gang of hard core emulator developers quietly slipping in and out of the building each day, carefully avoiding notice.
Hey, that has worked before.
A high school student I know got drunk, drove, and killed a fellow student when he decided that a living room would make a good parking spot. His public defender worked him to a five-year probation sentence and a few hundred hours of community service, as I recall.
"Affluenza" is indeed a problem, but despite the claims of the grieving father, I don't see it being a major factor in this case. Penalties for juveniles are lighter out of mercy, regardless of socioeconomic status. Where this kid's family may have helped is in convincing the judge that a trip to a rehab center (on their half-million-dollar dime) is better for society than a trip to jail.
I see no sarcasm. I see a valid argument.
The teenager who got drunk wasn't mature enough to be aware of the severity of his actions. That's why we have a juvenile system in the first place. Even if, while sober, he intended to get drunk and drive recklessly, he probably couldn't understand the risk involved. That's why his sentence is only 10 years' probation rather that jail time. It's a sentence that fits reasonably well with several counts of accidental manslaughter and a DWI.
On the other hand, Sabu indeed clearly set out to cause harm to others. Granted he may have considered it a noble cause, but that's beside the point. Crimes committed in the name of vigilantism are still crimes, and Sabu was mature enough to know the ramifications of his actions.
Yes... what a shame it is that we choose not to condemn our children for their mistakes, but rather sentence them to probation for a decade instead.
Probably. It's an ICANN ruling, so as far as I can tell it applies to all ICANN registrars.
What doesn't apply worldwide is the "court order". If an American court tries to issue a court order for a Chinese registrar to hold a name, the Chinese company is probably not required to follow the order, so per ICANN they'd have to release the name. On the other hand, a Chinese order would have jurisdiction, so the registrar would be able (and likely required) to hold the name.
If today $1 buys you one hotdog and your salary is $10/hour, yet a year from now $1 buys you two hotdogs yet your salary is $7.50/hour, your salary has gone "down"
What exactly is the rate of deflation in this example? The price of a hot dog dropped 50%, but the price of labor dropped only 25%.
and the prices are all halved, the result isn't a poorer economy - it's an economy in which everybody can buy twice as much stuff as before.
Nope. The price of labor must also be halved, so everybody can buy exactly what they could before.
Savings are what drive investments - an investment is basically taking a bunch of savings and applying it with the hope of making more money.
Investment is spending any asset toward creating a system to return more value than what was spent. Investing is not saving. When you buy into an investment, you do not keep ownership of your money. You buy a certificate saying you contributed a certain percentage to the endeavor.
You don't seem to understand what the point of commerce is. The whole reason commerce ever happens is to give people things they want. If I want a good, a functional economy should ensure that I have the resources to acquire that good. In a strong economy, everybody can get what they want easily - supply meets demand. The numbers on the currency don't matter at all for that purpose.
Unfortunately, humans don't think that way. They see the numbers and remember what numbers used to be. They predict where the numbers will be in the future, and they adjust habits based on that. with an increased demand for money, there is less money available to the people who want money in exchange for their products, including those who want to sell their labor directly. If labor costs stay perfectly in sync with the deflation, everything is fine, except workers will see the numbers on their paycheck continually decrease, so they'll cut spending even more, until they only purchase bare essentials for life. Yes, they could purchase the same amount as before, but they won't realize that when they're just seeing ever-smaller numbers in front of them.
Without people buying those nonessential goods, the companies making those goods will collapse, leaving those workers jobless (and even faster if wages deflate more slowly than the price of consumer goods). Those unemployed people see even smaller budgets for purchases, continuing the cycle. Eventually there is an equilibrium at the point of desperation, where people can produce just enough for themselves to survive, and all nonessential commerce is effectively halted. Excess production is pointless, because people won't spend the money to buy it.
That's what interest is for. Ideally, the (numeric) amount you owe rises along with the (numeric) amount the lender lost by letting you use their assets for the duration of the loan. In a perfect zero-sum deal, a borrower could take out a loan, invest the cash with inflation-only return, then repay their whole debt with no net transfer of value.
In practice, the interest rate also includes a factor for the lender's assumed risk that you'll default, and a factor for overhead costs, but the bulk of the interest is still covering inflation.
That's utterly backwards.
The US dollar works because the Federal Reserve promises to manipulate it.
What I want to know is, Why does Ford need this data?
As you noted, many people want their cars to have GPS functionality, and mechanics can benefit from a performance log, and some folks want their car to also be a cell phone, and remember recent radio stations, and so on. There's data storage to support the functions that the car's owners want, and if Ford actually wanted to get that data, they probably could. Either they could have the car transmit data through the cellular network, or just wait for it to come in for maintenance.
I read TFS as being a flippant and sarcastic remark highlighting how mundane data collection actually is. The same data the car could use to tune its performance could also be used to track the vehicle's whereabouts, but that would require Ford having any interest in the car's whereabouts. They're probably more interested in the performance data.
As a related analogy, I used to work in the medical data industry. My job was gathering private medical data. We had full access to medical records for a few million patients (including my wife and coworkers). The first thing we did with that data was wipe out the names and street address information, because they weren't important for our goal. Step two was to hash the unique patient ID number, which we needed to remain unique, but didn't care what it was. Finally, after various routes through statistical analysis, all of the numbers we produced were randomly fudged a little bit to make reidentification more difficult. The bottom line is that we had enough access to tons of highly-sensitive personal information to cause all sorts of trouble... but we just didn't care to do so.
Top line is perfect nuclear fuel. Bottom line is like smelted steel. What's in the middle, though? What material characteristics can be expected in a half-melted core?
The left over hydrogen cannot explode inside the reactor vessel because the oxygen is gone.
Despite the high risk of hydrogen (produced from the water in the containment vessel) igniting after combining with oxygen from water or in the atmosphere, and in order to release some of the pressure inside the reactor at Fukushima I unit 1, the decision is taken to vent some of the steam (which contained a small amount of radioactive material) into the air. ... To release pressure within reactor unit 1 at Fukushima I, steam is released out of the unit into the air. This steam contains water vapor, hydrogen, oxygen and some radioactive material, mostly tritium and nitrogen-16.
Sounds like there's enough oxygen left to go boom.
Question for everyone: does anyone know if Fukushima has the US style concrete containment buildings?
I'm not terribly familiar with the details of reactor design, but I believe you're referring to the outer containment vessel of a pressurized water reactor, which is designed mainly to protect against leaks of steam from the high-pressure cooling lines that come out of the main reactor vessel. In comparison, the Fukushima Daiichi reactors are boiling water reactors, which are smaller by design. Their containment vessel is small enough that it fits inside more normal-looking buildings.
I didn't claim otherwise.
Let's review...
in order to build safe containment vessel floors that can hold an ugly puddle of radioactive sludge.
So we did build such containment vessels? Then why did the Fukushima accident happen at all?
Floors are generally not considered "safe" based on their ability to contain an explosion, and per the subject of discussion, the only criteria I am referring to is indeed the ability to mitigate one particular kind of failure mode. If we expect a single mechanism to protect against every possible failure happening at once, we must also avoid all useful definitions of the words "safe". It's a block of concrete we're talking about, not Superman.
Engineers have been doing failure analysis on nuclear reactors since before sustained reactors were even considered feasible. Almost all individual failure modes are indeed accounted for and are perfectly within the equipment's capabilities to handle, and there are backups and failsafe mechanisms in place to further contain other problems.
The Fukushima Daiichi disaster was a product of multiple failures occurring simultaneously in combinations that were not foreseen in the failure analysis. It was expected that if the facility were damaged, it could be repaired within hours enough to get regular cooling systems operational, and it was expected that the emergency cooling systems would function during that time. Instead, the emergency systems did not perform as expected, backups were offline, and the whole facility was electrically isolated for over a week. That's why the Fukushima Daiichi disaster happened. The floor did its job admirably.
Fukushima's containment vessel could (and did) contain the molten core... but not the hydrogen explosions that also occurred inside the reactor chamber because of the total coolant loss.
My language should imply that nuclear reactors are safe against the foreseen failure modes. At Fukushima Daiichi, it was not expected that all of the coolant systems would fail at once and that repairs would be hampered by the tsunami damage.
Testing failure modes doesn't necessarily imply that the failure modes must be well-understood.
We know that, in a worst-case scenario, reactors can melt down into an ugly puddle of radioactive detritus. We don't understand the mechanics involved, and we didn't really need to in order to build safe containment vessel floors that can hold an ugly puddle of radioactive sludge.
Reaction rates are fairly well understood, as are the characteristics of the radiation itself, so it's fairly straightforward to build a containment vessel that can hold the whole experiment. As I understand it, what's not really well known is how the fuel itself behaves in a meltdown, because they are (fortunately) so rare. Apart from "everything melts and settles in a puddle at the bottom", we don't know how quickly it melts, how that affects reaction rates (though we know it doesn't explode like a nuclear bomb), or if there's any quirks (like hot or cool spots).
The baseline is the starting configuration, which they're building. The worst-reasonable-case scenario is easy enough to figure out, and protection can be built against that. It's the middle area that we don't understand.
And, it should be noted, they want to find out in controlled conditions with sufficient protective equipment in a facility explicitly configured for this kind of situation. This is science.
Ah, yes, because the unmanned probes are doing such a great job on the experiments where humans are the test subjects. At least those probes, carrying a dozen experiments each, are getting a lot of science done. After all, the ISS crew isn't busy or anything, right?