Today I Learned

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Today I learned that cleaning a white hat can be done with bleach cleaner, but it’s important to rinse it before wearing it again. I also discovered that "oyster veneering," a woodworking technique from the late 1600s, is experiencing a minor revival despite its labor-intensive nature. Additionally, I learned that the factorial of 23 (23!) equals 25,852,016,738,884,976,640,000, which interestingly has 23 digits, a unique coincidence among factorials. I found out that medical specialists often spend less than 10 minutes with patients, and that watching TV can contribute to weight gain. Other insights included the fact that a kiss can transfer around 80 million microbes, and that bureaucracy can sometimes hinder employment opportunities. The discussion also touched on various trivia, such as the emotional sensitivity of barn owls and the complexities of gravitational lensing around black holes.
  • #901
fresh_42 said:
He died in jail. However ##^{197}Hg## decays to gold :cool:

He went on the lam to Italy. He was captured, returned to Munich, served four years for the alchemy gig, got out of prison, passed bad checks, and eventually was sent back to jail.
 
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  • #902
Hornbein said:
He served four years for the alchemy gig, got out of prison, passed bad checks, and eventually was sent back to jail.
I can't believe it. They made a movie about his life.
 
  • #903
The Nazis were quite interested in the occult, symbolism and ancient philosophies.
And then during the cold war, there were experiments in paranormal phenomena on both sides.
 
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  • #904
Today I learned that explorer Alexander Humboldt -- Humboldt county is named after him -- cut open his back and inserted wires into the slots. He had discovered the battery, but much to his later regret didn't realize it.
 
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  • #905
Hornbein said:
Today I learned that explorer Alexander Humboldt -- Humboldt county is named after him -- cut open his back and inserted wires into the slots. He had discovered the battery, but much to his later regret didn't realize it.
Sounds like the earliest documented case of reefer madness. Now I know how Humboldt State got its name!
 
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  • #906
Today I learned that you can be sacked from work (part-time without contract) without boss even telling you. Other people will want to say good-bye to you because you won't come next week. oooohhhh Didn't boss tell you? :DDDDDD
 
  • #907
Sophia said:
Today I learned that you can be sacked from work (part-time without contract) without boss even telling you. Other people will want to say good-bye to you because you won't come next week. oooohhhh Didn't boss tell you? :DDDDDD
I think either part-time or full time or freelance job in a company does need a contract at least in my area. It can be suspended based on the contract agreement specified from the start. So for a full time contract, a laborer in my area can also cancel it himself with some notification sent to HR department 4-8 weeks before he can leave the company officially.
 
  • #908
Silicon Waffle said:
I think either part-time or full time or freelance job in a company does need a contract at least in my area. It can be suspended based on the contract agreement specified from the start. So for a full time contract, a laborer in my area can also cancel it himself with some notification sent to HR department 4-8 weeks before he can leave the company officially.

I was trying to tell that I got sacked today and my boss didn't even tell me. Other teachers at the kindergarten told me that we will not see each other again because the manager fired me :) New teacher will come next week. :)
The reason is that I wasn't able to manage discipline and kids were running wild. I don't deny it, of course it is true. But the manager could at least have the decency to tell me about that.
 
  • #909
Sorry to hear that...
 
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  • #910
Sophia said:
I was trying to tell that I got sacked today and my boss didn't even tell me. Other teachers at the kindergarten told me that we will not see each other again because the manager fired me :) New teacher will come next week. :)
The reason is that I wasn't able to manage discipline and kids were running wild. I don't deny it, of course it is true. But the manager could at least have the decency to tell me about that.
Oh, I am really sorry about that. I totally misunderstood your post. I would probably contact or directly meet the manager to ask for some clarification if I were you.
 
  • #911
Sophia said:
The reason is that I wasn't able to manage discipline and kids were running wild. I don't deny it, of course it is true. But the manager could at least have the decency to tell me about that.
I'm sorry to hear that. (Not that the children were running wild, but that you were sacked in such a way.) From some of your other posts I got the impression you are a kind person, maybe the children took advantage of that. In any case, good luck finding something new soon!
 
  • #912
Fortunately, I have other work too, making me 75% employed, so this isn't so bad. This kindergarten thing was just part time. I am not even a teacher by profession. That's why I got these problems with managing the kids. I'm just too soft. But the whole situation and manager's behaviour is kind of a shock.
Of course I am going to discuss this, even calling the authorities because there were some illegal things going on. I still wasn't paid for last 2 months. I demanded payment even before I discovered that I am fired but she told me she is in a hospital giving birth to a baby. She was really pregnant but that doesn't explain no money for November. I won't let it be. If I don't get the money next week they'll get a visit from some officials and they won't like it.
 
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  • #913
I learned that my new jeep wrangler with small MT tires can handle insane hills and mud.

I love my job sometimes
 
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  • #915
Sophia said:
Crazy modern marketing art :cool: http://www.bbc.com/news/world-asia-35320373

In Seminyak, Bali there's a wedding altar inside the shape of a cut diamond.

The-Diamond-Chapel.jpg


It sort of reminded me of a Star Trek space shuttle launch pad. I felt it would be way too hot inside.

15379760902_f267271a2d_z.jpg


But if that floats your boat, it's available. Beats the slipper, if you ask me.
 
  • #916
I like the diamond better, too. The slipper is too vulgar for my taste.
 
  • #917
I find diamonds to be vulgar. I love the idea, but I don't care for the slipper or diamond designs.
 
  • #918
Hornbein said:
... a Star Trek space shuttle launch pad.

Lol... not even close... :oldtongue:
 
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  • #919
Sophia said:
That's why I got these problems with managing the kids. I'm just too soft.
Big, big BS. It is ok to let children run wild as you expressed it. To discipline them at this age is wrong, although widely spread.
However, it does not excuse your boss from being such an ... that he didn't tell it personally.
 
  • #920
OCR said:
Lol... not even close... :oldtongue:

It's a solar power concentrator. They found out that subspace drive coarsened the granularity of the Klein-Gordon field, creating long-lasting chronosynclastic infibulae. So Starfleet Command went to solar power.
 
  • #921
Hornbein said:
So Starfleet Command went to solar power.

Dammit ... I'm always the last one to get informed! ... :oldgrumpy:And they knew I'd found a work around for that... :headbang:
They found out that subspace drive coarsened the granularity of the Klein-Gordon field, creating long-lasting chronosynclastic infibulae.
 
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  • #922
OCR said:
Dammit ... I'm always the last one to get informed! ... :oldgrumpy:
Keep your ears open and your eyes on the mark. (Rules of Acquisition #7)
 
  • #923
fresh_42 said:
(Rules of Acquisition #7)

Lol... :blushing:
 
  • #924
Boolean Boogey said:
I find diamonds to be vulgar. I love the idea, but I don't care for the slipper or diamond designs.
For me building churches of such shapes is an oxymoron.
A slipper or diamond shaped church is like a hamburger shaped gym.
 
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  • #925
Sophia said:
For me building churches of such shapes is an oxymoron.
A slipper or diamond shaped church is like a hamburger shaped gym.

They aren't churches, they are wedding chapels.

In Bali weddings are presided over by a priest but never take place in the temples.
 
  • #926
Hornbein said:
In Bali weddings are presided over by a priest but never take place in the temples.
Seems they know why. Very cautious people.
 
  • #927
According to Wikipedia, Alexander Graham Bell mistranslated a paper that had been written in German by Hermann von Helmholtz. This misunderstanding led Bell to the invention of the telephone.
 
  • #928
Hornbein said:
According to Wikipedia, Alexander Graham Bell mistranslated a paper that had been written in German by Hermann von Helmholtz. This misunderstanding led Bell to the invention of the telephone.
Mysteries at the Museum has a segment on Antonio Meucci, who is considered one of the leading contenders for having invented the telephone before Bell. The story they tell, is that Meucci personally submitted the telephone to some engineering firm (or something) but, since he could hardly speak English, he wasn't able to make clear what it was for. He gave them a working model to examine, but they shelved it and forgot about it. However, it turns out young Alexander Graham Bell was an employee of that firm.

Unfortunately, the same story is not repeated either in the wiki on Bell or in the one on Meucci. The implication is that Bell actually plagiarized the invention wholesale from this obscure inventor. I'd like to find the original source of the story.
 
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  • #930
fresh_42 said:
I have the impression that, when there's no money being disputed, the actual history probably gets sorted out. Tesla conceded that another inventor had probably beat him by a couple years in inventing the induction motor. However, the other guy was not trying to claim any of Tesla's earnings from it, and also was not claiming Tesla stole the idea. Additionally, Faraday conceded that an American inventor had demonstrated mutual inductance before he did. Here, again, though, there was no money at stake. These big invention disputes seem only to arise when the winner stands to make a lot of money.
 
  • #931
Every time a man puts a new idea across he finds ten men who thought of it before he did -- but they only thought of it.
-- Anon.

it's men of action who make the world go...
 
  • #932
jim hardy said:
it's men of action who make the world go...
The odds of fundraising and/or political connections might play a role as well.
 
  • #933
edward said:
Today I learned that a medical specialist will spend less than 10 minutes in the examination room with me. I also learned that after three minutes they start typing on the computer even if I am still talking. I did not learn if they can actually multitask.
Love the multi tasking observation, as in can they or not. Hilarious!
 
  • #934
Every time a man puts a new idea across he finds ten men who thought of it before he did -- but they only thought of it.
-- Anon.
Yeah, I was saying this exact same thing years before Anon was born.
 
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  • #935
Today I learned that the accident at Three Mile Island was due, in part, to a valve that was stuck open. The operators had no idea it was stuck open because they had an indicator light that they believed told them when it was open or closed. In fact, the indicator light only registered whether there was current or not to the solenoid that operated the valve. It did not occur to anyone until the next shift came on, that the solenoid could be energized without the valve having been closed by it, which, unfortunately, is exactly what had happened.

It was already known that these valves could get stuck open:
The Government Affairs Vice President confirmed that the Metropolitan Edison Company, which operated the company, had shortly before received a warning from the Nuclear Regulatory Commission (NRC) that Babcock & Wilcox reactor valves were vulnerable to failure under certain conditions. He said he had sent it on to the Vice President of Engineering, who confirmed that he had read it. Shortly after that, the two men met at the water cooler where the Government Affairs VP asked the Engineering VP a question. The Government Affairs VP remembered the question as "Is there a problem here?" The Engineering VP thought the question was "Have you solved the problem?" Both VPs agreed that the answer was "no." One walked away believing that the problem was solved. The other believed that he had informed his bosses that there was a problem.
-Wiki


 
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  • #936
zoobyshoe said:
The operators had no idea it was stuck open because they had an indicator light that they believed told them when it was open or closed.


I remember that morning well - it was really unnerving to hear of a plant in such trouble...
Soooo many confusing symptoms for those guys...
There's a temperature sensor downstream of that valve whose purpose is to detect hot fluid leaking past the valve.

The operators had not been trained to understand the ambiguous nature of the pilot-operated relief valve indicator and to look for alternative confirmation that the main relief valve was closed. There was a temperature indicator downstream of the pilot-operated relief valve in the tail pipe between the pilot-operated relief valve and the pressurizer that could have told them the valve was stuck open, by showing that the temperature in the tail pipe remained higher than it should have been had the pilot-operated relief valve been shut. This temperature indicator, however, was not part of the "safety grade" suite of indicators designed to be used after an incident, and the operators had not been trained to use it. Its location on the back of the desk also meant that it was effectively out of sight of the operators.
https://en.wikipedia.org/wiki/Three_Mile_Island_accident

You'd think, releasing 2250 psi/650 degree steam through the valve, it'd get pretty hot in the tailpipe downstream of the valve.
But steam cools when it throttles.
So with tailpipe temperature gauge showing not very hot it looked as if there wasn't flow,

which agreed with the valve's indicator light !


That's because of the the enthalpy curve for steam...
http://www.engineeringtoolbox.com/saturated-steam-properties-d_273.html
at 2250psi/650 degrees it's ~1114
at 15psi/250 degrees it's more , ~1164
so throttling 2250psi/650 degF steam to 15 psi you get a steam-water mix at ~250 degf

That modest temperature in the tailpipe wasn't thought unusual.

http://www.osti.gov/scitech/servlets/purl/5982361
upload_2016-1-17_5-37-49.png


Soooo many lessons were learned from that accident.
 
  • #937
So - communication failure by the VPs, failure to understand that the downstream sensor wouldn't respond as strongly to a valve failure as expected, a valve failure, user interface design failure and operator failure to put the signs together until shift change. Murphy was on top of his game that day, wasn't he?
 
  • #938
Ibix said:
Murphy was on top of his game that day, wasn't he?

There's a fascinating book i read over fifty years ago "Fate is the Hunter" by Ernest Gann.
He was a legendary airline pilot. The book is autobiographical . His investigations of airplane crashes point out that disasters always result from little insignificant things lining up like dominoes until some little something sets off a chain reaction. I believe that's how the small things of the Earth confound the mighty...

Murphy is an optimist. That's why a nuke plant is a good career for an OCD perfectionist .

https://en.wikipedia.org/wiki/Fate_Is_the_Hunter
it's still a good read
 
  • #939
Ibix said:
So - communication failure by the VPs, failure to understand that the downstream sensor wouldn't respond as strongly to a valve failure as expected, a valve failure, user interface design failure and operator failure to put the signs together until shift change. Murphy was on top of his game that day, wasn't he?
If one of those components would have been missing, we wouldn't have heard of it.

Anyway, 14 µSv additional dose on average - about the natural radiation everyone receives in two days, or the additional dose received from one hour of airplane flight.
Even if you add Chernobyl and Fukushima accidents and the normal operation, nuclear power leads to lower radiation doses released than coal power plants during normal operation.
 
  • #940
zoobyshoe said:
Today I learned that the accident at Three Mile Island ...
Shortly after I've seen a graffiti in a subway station here: "Chernobyl - Harrisburg 1:1"
 
  • #941
mfb said:
If one of those components would have been missing, we wouldn't have heard of it.
Indeed. I wasn't being down on them for failing to catch it (well, maybe the hidden warning light deserves a bit of a facepalm). One can always go back over any chain of events and find a point when someone could have averted the end, and I cannot claim any moral high ground here. :wink: It's just how bad their luck had to be to have so many opportunities go the wrong way.

It'd be interesting to know how many times they've added a page to The Book because of a situation like this that they caught versus the number of times they didn't catch it.
 
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  • #942
Ibix said:
Indeed. I wasn't being down on them for failing to catch it (well, maybe the hidden warning light deserves a bit of a facepalm). One can always go back over any chain of events and find a point when someone could have averted the end, and I cannot claim any moral high ground here. :wink: It's just how bad their luck had to be to have so many opportunities go the wrong way.

It'd be interesting to know how many times they've added a page to The Book because of a situation like this that they caught versus the number of times they didn't catch it.
In the section called "lessons learned" they introduce Charles Perrows concept of Normal Accident Theory. Clicking on that leads to an article entitled System Accident:

In a December 2012 article in a popular magazine, Charles Perrow writes, "A normal accident is where everyone tries very hard to play safe, but unexpected interaction of two or more failures (because of interactive complexity), causes a cascade of failures (because of tight coupling)."[3]

There is an aspect of an animal devouring its own tail, in that more formality and effort to get it exactly right can make the situation worse.[4] For example, the more organizational rigmarole involved in adjusting to changing conditions, the more employees will delay in reporting the changing conditions, and the more emphasis on formality, the less likely employees and managers will engage in real communication. New rules can actually make the situation worse, both by adding a new additional layer of complexity and by reminding employees yet again that they are not to think but are just to follow the rules.
Indeed, the trigger of the accident at Chernobyl was a scheduled test to determine if a safety feature was working.
 
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  • #943
jim hardy said:
Soooo many lessons were learned from that accident.
I'm sure. The problem is that the next big accident, Chernobyl, arose from a completely different "perfect storm" of minor glitches, and Fukushima was triggered by forces completely out of human hands.

Nuclear power plants are just one example of a complex system that's vulnerable to it's own complexity. The example that's really through the roof is the DoD budget:
https://www.physicsforums.com/threads/the-pentagons-doctored-ledgers-conceal-epic-waste.727651/
If you read the (unfortunately very long) article Greg linked to, you may come to the conclusion I did, which is that the problem there is completely unfixable.
 
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  • #944
What makes me angry about nuclear power plants is, that if you start to completely calculate total costs, i.e. costs for their wastes included, they immediately stop to deliver cheap energy. It's somehow unfair that profits go to the share holders and costs to the community. Am I the only one who sees this?
 
  • #945
mfb said:
Even if you add Chernobyl and Fukushima accidents and the normal operation, nuclear power leads to lower radiation doses released than coal power plants during normal operation.
I've never looked into radiation released by coal power plants, but, correct me if I'm wrong, I would assume the radiation they release is very much more spread out, and that the problem with nuclear accidents is how concentrated the released radiation is.
 
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  • #946
fresh_42 said:
What makes me angry about nuclear power plants is, that if you start to completely calculate total costs, i.e. costs for their wastes included, they immediately stop to deliver cheap energy. It's somehow unfair that profits go to the share holders and costs to the community. Am I the only one who sees this?
I haven't even looked into it. But on that subject, a nuclear accident must be astronomically expensive. You lose all the money put into building the affected reactor, you lose the revenue from the power it would have generated, and then you have to pour vast amounts into clean up and lawsuits. That has to affect the profitability of all the remaining nuclear power plants that didn't have big accidents. The radiation at Chernobyl is so bad they had to abandon the other three operational reactors there and stop work on the two more they had planned.
 
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  • #947
Yep. Uninsurable.
 
  • #948
fresh_42 said:
What makes me angry about nuclear power plants is, that if you start to completely calculate total costs, i.e. costs for their wastes included, they immediately stop to deliver cheap energy. It's somehow unfair that profits go to the share holders and costs to the community. Am I the only one who sees this?
Where are those costs not included? Every opponent of nuclear power makes sure they get overestimated as much as possible.
zoobyshoe said:
I've never looked into radiation released by coal power plants, but, correct me if I'm wrong, I would assume the radiation they release is very much more spread out, and that the problem with nuclear accidents is how concentrated the released radiation is.
There were two accidents where the radiation levels exceeded those from typical coal power plants. None of them were at a level where direct consequences (radiation sickness and similar) would be a problem for the population. That leaves the low-radiation dose effects, which are expected to be linear with dose. "Expected" because their effects are too small to be significantly notable in scientific studies.
The concentration makes bad PR, but it is actually helpful: in the extremely rare cases of accidents, you can move away. You cannot move away from coal power plants.

zoobyshoe said:
But on that subject, a nuclear accident must be astronomically expensive.
So are the total expenses coming from coal power plants. The costs are just more hidden. There are various estimates on lifes saved from using nuclear power instead of coal, but they are all in the range of millions (e.g. 1.8 millions here, http://pubs.giss.nasa.gov/docs/2013/2013_Kharecha_Hansen_1.pdf[/URL] and so on). There are attempts to put a [url=http://www.theglobalist.com/the-cost-of-a-human-life-statistically-speaking/]monetary value on human lifes[/url], typically around 5 millions. Multiply both together and nuclear power saved ten trillions, potentially tens of trillions, just based on the waste coal power plants that got avoided - several billions per operational power plant. That is not even including the CO2 emitted and its consequences!
Coal is by far the most expensive reliable source of power we have, if you include all the effects. But coal is the alternative to nuclear power today - shut down nuclear power plants and coal power plants appear.
 
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  • #949
mfb said:
There were two accidents where the radiation levels exceeded those from typical coal power plants. None of them were at a level where direct consequences (radiation sickness and similar) would be a problem for the population.
You mean Chernobyl and Fukushima?
That leaves the low-radiation dose effects, which are expected to be linear with dose. "Expected" because their effects are too small to be significantly notable in scientific studies.
The concentration makes bad PR, but it is actually helpful: in the extremely rare cases of accidents, you can move away. You cannot move away from coal power plants.
Why can't you move away from a coal plant?
So are the total expenses coming from coal power plants. The costs are just more hidden. There are various estimates on lifes saved from using nuclear power instead of coal, but they are all in the range of millions (e.g. 1.8 millions here, http://pubs.giss.nasa.gov/docs/2013/2013_Kharecha_Hansen_1.pdf[/URL] and so on). There are attempts to put a [URL='http://www.theglobalist.com/the-cost-of-a-human-life-statistically-speaking/']monetary value on human lifes[/URL], typically around 5 millions. Multiply both together and nuclear power saved ten trillions, potentially tens of trillions, just based on the waste coal power plants that got avoided - several billions per operational power plant. That is not even including the CO2 emitted and its consequences!
Coal is by far the most expensive reliable source of power we have, if you include all the effects. But coal is the alternative to nuclear power today - shut down nuclear power plants and coal power plants appear.[/QUOTE]
That pretty much supports what I was saying: a nuclear accident must be astronomically expensive. Your information makes it more so, since it means resorting to more expensive coal plants.
 
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  • #950
mfb said:
Where are those costs not included? Every opponent of nuclear power makes sure they get overestimated as much as possible.
You can't believe this. This is simply not true, and I wondered if you would not know. May I ask whether you receive money for making those funny statements? *)

Nobody on this planet can afford to a) build thousands of safe places for nuclear waste over and over again and b) guarantee to safely guard it for the next 40 billion years.
Nobody can afford to insure the risk of a major accident as it happened already twice in about 50 years since we started to use fission.
If you really price in these two factors of costs nuclear energy couldn't be afforded by anyone. These costs are simply spread over the entire community and over the forthcoming 50 billion years.

*) Arguments only hold in characteristic zero case with prime field ℚ.
 
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