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Interesting Koti.
We have an electrical room in one of our buildings with a Halon fire suppression system.
We ( JHSC ) had it taken off-line because  of asphyxiation risks.
 

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Today I learned that skills improved by participating here on scienceforums can, at least in some minor way, be helpful in the current virus situation. I joined a local initiative where students study

I found out you can be superstitious, but not a little bit stitious.

Today I learned that you only need 39 digits of π to calculate the circumference of the observable universe with a precision of one atom.

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39 minutes ago, MigL said:

Interesting Koti.
We have an electrical room in one of our buildings with a Halon fire suppression system.
We ( JHSC ) had it taken off-line because  of asphyxiation risks.
 

The effective concentration, in a fire, of halon does not hinder respiration. It's not like carbon dioxide in its action.

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Halon is similar to CO2 in that it is suitable for use in cold weather and leaves no residue. Unlike CO2, however, Halon does not displace the air out of the area where it is dispensed. Even for the toughest fires, less than an 8% concentration of Halon by volume is required, leaving plenty of air to use in the evacuation process. Also, unlike CO2, there is no danger of "cold shocking" avionics or other sensitive electrical equipment. https://www.h3rcleanagents.com/support_faq_2.htm

 

Edited by StringJunky
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13 hours ago, koti said:

Today I learned that in the late 70’s, IBM used halon gass as a fire suppressant inside their hard drives which had air tight casings. The drives were 9 plates traditional mechanical technology, 10Mb capacity at 38kg weight, about the size of a full ATX desktop PC and cost around 250K USD. The story goes that the server rooms where the drives were operating were filled with Halon gas as well to mitigate the risk of fire.

I didn't know they were hard drives in the 70's. I remember tapes & punchcards. Our first computer at the office (Aviette I cannot recall the rest) had no hard drive at all.

Edited by michel123456
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3 hours ago, michel123456 said:

I didn't know they were hard drives in the 70's. I remember tapes & punchcards. Our first computer at the office (Aviette I cannot recall the rest) had no hard drive at all.

Late 70’s early 80’s, its not clear from this info. At 250 thousand dollars they were probably more of an experimental thing back then:

https://www.google.pl/amp/s/www.geek.com/chips/teardown-inside-a-250000-10mb-hard-drive-1531755/%3famp=1

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The commercial usage of hard disk drives began in 1957, with the shipment of a production IBM 305 RAMAC system including IBM Model 350 disk storage.[4]US Patent 3,503,060 issued March 24, 1970, and arising from the IBM RAMAC program is generally considered to be the fundamental patent for disk drives.[5]

https://en.wikipedia.org/wiki/History_of_hard_disk_drives

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34 minutes ago, amato said:

Today I learned that the law of conservation of energy has a philosophical significance. From the point of view of dialectical materialism, the law of conservation of energy, like other conservation laws, is a natural scientific justification for the provision on the unity of nature, since it indicates the natural character of the transformation of certain forms of movement into others, reveals a profound inner connection existing between all forms of motion.

That doesn't make much sense. Energy is not necessarily connected with movement. And it isn't energy that is conserved, it is mass+energy. And, on the scale of the universe, it isn't clear that energy is conserved anyway.

What does dialectical materialism have to say about that? :)

But there is a much deeper significance to conservation laws generally. They are a consequence of particular symmetries. And it seems that symmetries underly pretty much everything in physics. 

Edited by Strange
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Today I learned that most missiles are actually solid fuel rather than liquid fuel, due to their ability to remain usable for decades without having to worry about the corrosive effects of liquid fuel.

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The more advanced missiles, such as the MBDA Meteor, a beyond visual range air to air missile with a range of 100km, and used by the customer nations of the Eurofighter Typhoon, Dassault Rafale, SAAB Gripen and F-35 of the Italian Air Force/Navy ( demonstrably more advanced than the Raytheon AMRAAM ), uses a solid propellant inside of a ramjet duct.
When the solid propellant used for acceleration is used up, the ramjet kicks in for sustaining and terminal maneuvering.
Older designs lacked this ability and could be defeated by hard maneuvering during the terminal approach to the target.
 

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Today I learned (or rather it struck me) that I see a fundamental difference between western and asian worlds - a „westerner” when sittng on a bench in a park by himself observes whats around him, trees, grass, etc - theres a distinction between „me” and „nature” where the „asian” world see themselves as an intrinsic part of that surrounding nature, it doesn’t surround them - they’re a part of it. 

I don’t know if I make much sense but there  it is.

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29 minutes ago, koti said:

Today I learned (or rather it struck me) that I see a fundamental difference between western and asian worlds - a „westerner” when sittng on a bench in a park by himself observes whats around him, trees, grass, etc - theres a distinction between „me” and „nature” where the „asian” world see themselves as an intrinsic part of that surrounding nature, it doesn’t surround them - they’re a part of it. 

I don’t know if I make much sense but there  it is.

I've been reading the online Japan Times for a while and they do think differently in many ways... some are better and some aren't but they do celebrate nature in a bigger way than we do. 

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On 4/14/2018 at 3:39 AM, koti said:

Today I learned (or rather it struck me) that I see a fundamental difference between western and asian worlds - a „westerner” when sittng on a bench in a park by himself observes whats around him, trees, grass, etc - theres a distinction between „me” and „nature” where the „asian” world see themselves as an intrinsic part of that surrounding nature, it doesn’t surround them - they’re a part of it. 

I don’t know if I make much sense but there  it is.

I am not sure. If existing it is at best a highly subtle difference and probably more on a linguistic than a perspective level. If you talk to Asians or Europeans regarding their observations there is generally no difference in their recounting if they explain their observation and their position in it, at least if both speak e.g. English. However, if you are talking about general philosophy, then yes, there is a difference in perspective with regard to nature. That, however, does not necessarily translate down to individual behaviour. 

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18 hours ago, CharonY said:

I am not sure. If existing it is at best a highly subtle difference and probably more on a linguistic than a perspective level. If you talk to Asians or Europeans regarding their observations there is generally no difference in their recounting if they explain their observation and their position in it, at least if both speak e.g. English. However, if you are talking about general philosophy, then yes, there is a difference in perspective with regard to nature. That, however, does not necessarily translate down to individual behaviour. 

It’s definitely due to philosophy or probably buddhism for that matter. I’ve had this notion of general perception/perspective of what/where/who we are with regard to nature come up a few times. I think its a good thing and its certainly something that I/we don’t have here where I live.

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2 hours ago, koti said:

It’s definitely due to philosophy or probably buddhism for that matter. I’ve had this notion of general perception/perspective of what/where/who we are with regard to nature come up a few times. I think its a good thing and its certainly something that I/we don’t have here where I live.

I would always be careful with those stereotypes, even if they are positive. These assumptions often lead to some kind of unconscious assumptions, which may not be harmful, but generally are not useful, either. Specifically one could easily argue that the Eastern area covers a wide range of diverse cultures and from that alone one can deduce that the viewpoints are likely to be vastly different. In addition, while certain philosophical viewpoints may be more dominant, their effect on the individual are going to be coloured by individual experiences. As an example, in the West it is undeniable that Christian teachings have a massive effect on Western history, philosophy and culture. But how it manifests is very diverse, ranging from literal adherence to a vague recognition.

It is a lesson that I learned from teaching students from very different backgrounds, trying to be sensitive to cultures does not work well usually, since unless one is immersed in it, much will be based on these types of stereotypes. From self-observation I realized that I thereby assume the students from other backgrounds to be, well, different which did not help the teaching process at all. While one can be cognizant of differences, commonly agreeing to some ground rules based on individual preferences rather than assumed cultural ones were far more helpful in establishing a good mentor relationship. 

This is not to say that there are no differences, especially when one starts to discusses worldviews (or philosophy). But on most specific, narrow topics or events  (as the description of a park for example) the context will be more relevant than the cultural background. 

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7 minutes ago, CharonY said:

I would always be careful with those stereotypes, even if they are positive. These assumptions often lead to some kind of unconscious assumptions, which may not be harmful, but generally are not useful, either. Specifically one could easily argue that the Eastern area covers a wide range of diverse cultures and from that alone one can deduce that the viewpoints are likely to be vastly different. In addition, while certain philosophical viewpoints may be more dominant, their effect on the individual are going to be coloured by individual experiences. As an example, in the West it is undeniable that Christian teachings have a massive effect on Western history, philosophy and culture. But how it manifests is very diverse, ranging from literal adherence to a vague recognition.

It is a lesson that I learned from teaching students from very different backgrounds, trying to be sensitive to cultures does not work well usually, since unless one is immersed in it, much will be based on these types of stereotypes. From self-observation I realized that I thereby assume the students from other backgrounds to be, well, different which did not help the teaching process at all. While one can be cognizant of differences, commonly agreeing to some ground rules based on individual preferences rather than assumed cultural ones were far more helpful in establishing a good mentor relationship. 

This is not to say that there are no differences, especially when one starts to discusses worldviews (or philosophy). But on most specific, narrow topics or events  (as the description of a park for example) the context will be more relevant than the cultural background. 

I had exactly your thoughts while posting this and I realize why you took my post as stereotyping. I actually have little knowledge on eastern cultures and my only goal with these thoughts was to learn more. I agree that stereotyping is a slippery slope even if the intentions are positive, theres this saying in my language: „Officiousness is worse than fascism” and it applies here. I too have experience with teaching people from different backgrounds and cultures, I actually developed a mechanism to be sensitive to a degree to other cultures while in formal situations, finding common things always worked for me because there is always common ground to be found however vastly different cultures I dealt with -  in this context I have to disagree that full immersion is neccesary, I noticed that people value certain levels of empathy towards their culture and being sincere always worked for me. I can certainly see why you value your approach, mine is risky and it requires a certain type of behaviour/approach which seems to come naturaly to me. As for stereotyping, I’m so not built for it, theres alwas some level of prejudice and stereotyping in all of us but I rather not waste my time on it as it leads to dead ends. 

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1 hour ago, koti said:

I actually have little knowledge on eastern cultures and my only goal with these thoughts was to learn more.

Just to make sure, it was not supposed to be a criticism, When one starts off learning something completely new, everything may seem new and weird. But usually it takes some deeper knowledge to figure out what differences are relevant and which are superficial. My comment on immersion was aimed at a priori assumptions about interpretation of cultural norms without actually understanding them. There are concepts that I feel are overrated or misunderstood (the concept of "face" for example). It does not mean that it is wrong to be sensitive (especially at the beginning). Rather, what I meant is  that one should not come with strong preconceptions and use those instead of what the interaction with the folks actually tells you ("no I am pretty sure that you are offended by this, I read it in a book"), if that makes sense. 

As a silly example, I remember from my time in Poland ,that it was impressed upon us that stirring ones teacup loudly was offensive and we have to take great care not to do that (without further explanation). Only to find out that no one really cared about it unless you are kind of obnoxiously playing around with it.

 

Edit: the context of the interactions are also relevant of course. Meeting someone's parents-in-law in a different country would require a different approach than interacting with co-workers or student, for example...

Edited by CharonY
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10 hours ago, CharonY said:

...) Meeting someone's parents-in-law in a different country would require a different approach than interacting with co-workers or student, for example...

Oh yes I have lived such an experience.

_Another example is the Manager (or CEO) traveling to find business opportunities: interacting with another culture can be messy and it is highly recommended to get as much as possible information before proceeding.

 

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30 minutes ago, michel123456 said:

Another example is the Manager (or CEO) traveling to find business opportunities: interacting with another culture can be messy and it is highly recommended to get as much as possible information before proceeding.

Several times I have been in meetings with managers/salespeople sent out from the European head office to meet with potential customers in Japan. After a meeting where presentations and discussions were met with "yes, yes, very interesting" I had to try and explain why that meant "no, we are not interested".

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12 minutes ago, Strange said:

Several times I have been in meetings with managers/salespeople sent out from the European head office to meet with potential customers in Japan. After a meeting where presentations and discussions were met with "yes, yes, very interesting" I had to try and explain why that meant "no, we are not interested".

Thats funny. I’d go on a limb and say that if you had to explain that to the sales people they’re not very good sales people. 

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14 minutes ago, koti said:

Thats funny. I’d go on a limb and say that if you had to explain that to the sales people they’re not very good sales people. 

I would say, just not aware of the cultural differences. The good ones learned pretty quickly to read between the lines of what was said.

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Today I learned about the UDC system Universal Decimal Classification, and about the Mundaneum, a forerunner of Wikipedia.

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The UDC was developed by the Belgian bibliographers Paul Otlet and Henri La Fontaine at the end of 19th Century. In 1895, they created Universal Bibliographic Repertory (Répertoire Bibliographique Universel) (RBU) which was intended to become a comprehensive classified index to all published information

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5ae1f0af313ce_ScreenShot04-26-18at06_30PM.JPG.303e7efa60fa3e19a1eaacd835466b23.JPG

https://en.wikipedia.org/wiki/Universal_Decimal_Classification#Main_tables

https://en.wikipedia.org/wiki/Mundaneum

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Today I learned....but still have trouble believing.... That the entire population of this planet could be packed into a cube that is a mere one cubic mile.

Further....and a bit humbling...said cube could be dropped into the middle of any ocean and the corresponding sea levels would not rise even one inch.

Feel small yet?

Cheers.

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11 hours ago, Velocity_Boy said:

Today I learned....but still have trouble believing.... That the entire population of this planet could be packed into a cube that is a mere one cubic mile.

The entire population could also fit in Rhode Island. But it wouldn't end well: https://what-if.xkcd.com/8/

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