Go Back   English Forum Switzerland > Off-Topic > Off-Topic > General off-topic
Reply
 
Thread Tools Display Modes
  #1101  
Old 24.06.2010, 20:42
mirfield's Avatar
Moddy McModface
 
Join Date: Apr 2007
Location: Basel
Posts: 8,190
Groaned at 50 Times in 44 Posts
Thanked 8,043 Times in 2,943 Posts
mirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
3. Seatbelts are mostly in place to help identify victums according to the flight manifest
Really? I'd be interested in seeing a cite for that.


Quote:
View Post
4. That's why you have to stay in your seat for take off and landing.
And not, for example, because people tumbling around the cabin tends to lead to injuries?
Reply With Quote
  #1102  
Old 25.06.2010, 02:03
TidakApa's Avatar
Forum Legend
 
Join Date: Jun 2009
Location: Top of a Triangle
Posts: 3,009
Groaned at 42 Times in 33 Posts
Thanked 5,673 Times in 2,039 Posts
TidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
Really? I'd be interested in seeing a cite for that.




And not, for example, because people tumbling around the cabin tends to lead to injuries?
I sat in a classroom studying to pass the CASA course. The question about seatbelts was raised and discussed directly.

We asked why we have to wear a 'lap' seatbelt if you hit the ground at an incredible speed. It's clear that you stand next to no chance of survival.

It helps prevent injuries in a light accident yes, but it is also very helpful to quickly identify hundreds of victims in fatal accidents.
You raised the point "people tumbling around the cabin"....this is exactly what it prevents. It keeps the bodies in the seat to line up with who sat in seat 22A for example in a plane of a couple of hundred people. I can't imagine anyone wants to make their job harder with identifying the deceased.

The lecturer went on to talk about rescues and the window shutter etc.(missing people in rescue attempts) and how all these things come into place. During the course of aircraft crash investigations, the findings also produce suggestions on how to prevent these things from happening again, hence - put your seatbelt on for take off and landing, and raise the shutters.

They won't cite these things, because it isn't necessary to justify why they enforce these Civil air laws. They don't have to, they are rules and you follow them. It was just interesting to hear how the laws came about, and why they are in force.

I am sorry I can't cite something and reference it directly for you as I'm only relaying a first hand story I heard sitting in a classroom. I'm sure these things can be researched though.

Ha Ha.....I guess it's also perhaps nicer for people who fly to hear "fasten your seatbelts please" and they are thinking "oooh, turbulence, I might bump my head", as opposed to "fasten your seatbelts, in case the pilot balls this landing up and you all die !!!"
Reply With Quote
  #1103  
Old 25.06.2010, 08:22
BeastOfBodmin's Avatar
Forum Veteran
 
Join Date: Oct 2006
Location: Zürich
Posts: 812
Groaned at 1 Time in 1 Post
Thanked 309 Times in 210 Posts
Blog Entries: 2
BeastOfBodmin has a reputation beyond reputeBeastOfBodmin has a reputation beyond reputeBeastOfBodmin has a reputation beyond reputeBeastOfBodmin has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
What are the chances of the lottery numbers being sequential?
The odds are the same as for any selection of numbers. I don't play, so I will make one up as an example.

Pick 5 + 1 bonus from 50.

All sequences have the same probability of occuring.

1/50 * 1/49 * ... 1/45 = 0.000000000087403

Quote:
View Post
Arguing that there's no point in ever picking sequential numbers for your ticket as it's much more likely that non sequential numbers would appear.
I think that strategy has merits. As each sequence is equally likely, then pick one that is less likely to be popular.

Quote:
View Post
I thought that in the long run, any set of numbers would have exactly the same chance of winning, sequential or not, as each combination of numbers is equally unlikely to win you the jackpot.
Yes.
Reply With Quote
  #1104  
Old 25.06.2010, 10:34
cyrus's Avatar
Forum Legend
 
Join Date: Nov 2006
Location: Emmenbruecke
Posts: 2,871
Groaned at 34 Times in 31 Posts
Thanked 3,261 Times in 1,420 Posts
cyrus has a reputation beyond reputecyrus has a reputation beyond reputecyrus has a reputation beyond reputecyrus has a reputation beyond reputecyrus has a reputation beyond reputecyrus has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
It helps prevent injuries in a light accident yes, but it is also very helpful to quickly identify hundreds of victims in fatal accidents.
You raised the point "people tumbling around the cabin"....this is exactly what it prevents. It keeps the bodies in the seat to line up with who sat in seat 22A for example in a plane of a couple of hundred people. I can't imagine anyone wants to make their job harder with identifying the deceased.
So how does that work with the budget airlines where getting seats is a free for all?
Reply With Quote
  #1105  
Old 25.06.2010, 11:55
Ouchboy's Avatar
Forum Legend
 
Join Date: Jun 2008
Location: Baden
Posts: 3,032
Groaned at 33 Times in 28 Posts
Thanked 4,545 Times in 1,776 Posts
Blog Entries: 19
Ouchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond repute
Re: Ask a Scientist

I want to create a feistel cipher were in the S-boxes I take the bitstring down, flip it and reverse it...

would that work?
Reply With Quote
  #1106  
Old 25.06.2010, 12:08
MathNut's Avatar
Forum Legend
 
Join Date: Aug 2007
Location: Kt. Glarus
Posts: 4,232
Groaned at 35 Times in 33 Posts
Thanked 9,962 Times in 3,068 Posts
MathNut has a reputation beyond reputeMathNut has a reputation beyond reputeMathNut has a reputation beyond reputeMathNut has a reputation beyond reputeMathNut has a reputation beyond reputeMathNut has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
I want to create a feistel cipher were in the S-boxes I take the bitstring down, flip it and reverse it...

would that work?
It would work - as in, you could send messages with it - but it wouldn't be particularly secure, no.

An S-box wants to be nonlinear (for starters) and that one isn't.
Reply With Quote
  #1107  
Old 25.06.2010, 12:16
Ouchboy's Avatar
Forum Legend
 
Join Date: Jun 2008
Location: Baden
Posts: 3,032
Groaned at 33 Times in 28 Posts
Thanked 4,545 Times in 1,776 Posts
Blog Entries: 19
Ouchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond reputeOuchboy has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
It would work - as in, you could send messages with it - but it wouldn't be particularly secure, no.

An S-box wants to be nonlinear (for starters) and that one isn't.

Damn Missy elliot and her songs...

Reply With Quote
  #1108  
Old 25.06.2010, 15:00
TidakApa's Avatar
Forum Legend
 
Join Date: Jun 2009
Location: Top of a Triangle
Posts: 3,009
Groaned at 42 Times in 33 Posts
Thanked 5,673 Times in 2,039 Posts
TidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
So how does that work with the budget airlines where getting seats is a free for all?
Very good question....... I don't know.

I haven't flown on an airline where I wasn't allocated a seat before. I don't even know if there is a carrier in Australia that does this, but you are right, clearly there are other carriers who do this. I assume the seatbelt on take off and landing and shutter up rule must still apply.

It's getting a little off topic now, and am now outside my depth. I don't know in detail how laws apply to airlines. In my defense, all I can say is that I am relaying information learnt during a "Commercial Helicopters Pilots licence" in Australia, where we studied alongside Fixed wing pilots. We only studied the laws applying to passenger fixed wing aircraft (as the same applies to Helicopters as well).

All I can say is that in class we reviewed examples and publications of airline crashes to demonstrate how and why some laws came about - and this included the seatbelt for take off and landing, and why shutters remain up (I now recall something about adjusting your eyes to the outside light and why cabin lights are off for takeoff and landing -but lets not make this trickier than this already is- however, how night vision works in your eyes is really interesting, but that's another story).

I guess with the example of a budget airline, a safe conclusion is that seatbelts for take off and landing are primarily for safety purposes, however in a worst case scenario there is the added advantage of identifying victims earlier where possible. For most flights where a seat allocation applies this identification assists a lot more.

.......Ha Ha, and STILL no one has answered my "Boiling water" question. An "excited state" of water changing soundwaves is good (and seriously, thanks for that), but it's the "Why and How" it does this that interests me.
Reply With Quote
  #1109  
Old 25.06.2010, 18:22
mirfield's Avatar
Moddy McModface
 
Join Date: Apr 2007
Location: Basel
Posts: 8,190
Groaned at 50 Times in 44 Posts
Thanked 8,043 Times in 2,943 Posts
mirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
why shutters remain up (I now recall something about adjusting your eyes to the outside light and why cabin lights are off for takeoff and landing
You're right about these two, but I'm not convinced that what you told about seatbelts is correct.

(Cabin crew have to wear their seatbelts too, and they're wearing a badge with their name on it.)
Reply With Quote
  #1110  
Old 25.06.2010, 18:24
mirfield's Avatar
Moddy McModface
 
Join Date: Apr 2007
Location: Basel
Posts: 8,190
Groaned at 50 Times in 44 Posts
Thanked 8,043 Times in 2,943 Posts
mirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond reputemirfield has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
I want to create a feistel cipher were in the S-boxes I take the bitstring down, flip it and reverse it...
Quote:
View Post
An S-box wants to be nonlinear (for starters) and that one isn't.


Can anyone explain that for a layperson?
Reply With Quote
  #1111  
Old 25.06.2010, 19:10
weejeem's Avatar
Forum Legend
 
Join Date: Nov 2008
Location: .
Posts: 3,728
Groaned at 37 Times in 31 Posts
Thanked 5,874 Times in 2,467 Posts
weejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
.......Ha Ha, and STILL no one has answered my "Boiling water" question. An "excited state" of water changing soundwaves is good (and seriously, thanks for that), but it's the "Why and How" it does this that interests me.
As the water temperature rises, the average number of hydrogen bonds between the water molecule gets progressively lower; i.e. there is a lowering of the viscosity of the liquid. This change in viscosity directly influences the size of the "lumps" that result as the liquid impacts on a surface, which in turn results in a different pitch.
Reply With Quote
  #1112  
Old 25.06.2010, 19:20
weejeem's Avatar
Forum Legend
 
Join Date: Nov 2008
Location: .
Posts: 3,728
Groaned at 37 Times in 31 Posts
Thanked 5,874 Times in 2,467 Posts
weejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
I want to create a feistel cipher were in the S-boxes I take the bitstring down, flip it and reverse it...

would that work?
Quote:
View Post
It would work - as in, you could send messages with it - but it wouldn't be particularly secure, no.

An S-box wants to be nonlinear (for starters) and that one isn't.
Quote:
View Post


Can anyone explain that for a layperson?

I think what they're trying to say is that for a block cipher based on a Feistel network to be resistant to linear and differential cryptanalysis, it is important that the substitution box (the "S-Box") design is such that not only should S(x) possess good characteristics, but so should S(S(x)), S(S(S(x))) and so on up to the numbers of rounds of the specific cipher concerned.
Reply With Quote
  #1113  
Old 25.06.2010, 19:37
the_clangers's Avatar
Forum Veteran
 
Join Date: Sep 2009
Location: St. Louis, MO was St Prex, VD
Posts: 2,000
Groaned at 18 Times in 15 Posts
Thanked 1,185 Times in 697 Posts
the_clangers has a reputation beyond reputethe_clangers has a reputation beyond reputethe_clangers has a reputation beyond reputethe_clangers has a reputation beyond reputethe_clangers has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
Oh, and I see that this topic has been touched on before, and in cases answered correctly.... But I did study for a commercial helicopter pilots licence and can confirm:
1. Window shutters are open on take off and landing for emergency crews in the event of an accident.
2. Most accidents happen at take off and landing
3. Seatbelts are mostly in place to help identify victums according to the flight manifest.... and reverting back to point 2.
4. That's why you have to stay in your seat for take off and landing.

It sounds a bit morbid, but if the plane goes down and you need to remove any surviving passengers, you need to do this quickly, so you don't want to miss anybody because the shutters are closed.

oh, and one more
5. Cabin crew should know this.

I did just post a question, so I thought I should throw my two cents in.
Interesting, because I was told by a pilot and crew that I could not move before take off. Once the plane was in the air they didn't care where we sat. The reason is that the datum for the airplane is computed and if people move around it makes it harder for the pilot to safely take off and land.

That is why when you are taking off or getting ready for final approach they don't want you moving around. The best way to stop that is to make everyone wear their seat belts. The last thing the pilot wants is for the the center of mass to change in the airplane during final.

Not to mention that the most likely time for injury due to banging into things and other people is during take off and landing.

I am sure that ID'ing people if their is an accident is laudable but I doubt it is the main reason for this requirement.

As another example, my father saw a flight attendant hit the ceiling due to severe unexpected turbulence. He never had trouble wearing his seatbelt after that.
__________________
Many men, of course, became extremely rich, but this was perfectly natural, and nothing to be ashamed of, because no one was really poor -- at least no one worth speaking of. - Douglas Adams
Reply With Quote
  #1114  
Old 26.06.2010, 13:08
weejeem's Avatar
Forum Legend
 
Join Date: Nov 2008
Location: .
Posts: 3,728
Groaned at 37 Times in 31 Posts
Thanked 5,874 Times in 2,467 Posts
weejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond reputeweejeem has a reputation beyond repute
Re: Ask a Scientist

And with the blinds down, we'd also miss moments like this...

Reply With Quote
  #1115  
Old 26.06.2010, 18:29
TidakApa's Avatar
Forum Legend
 
Join Date: Jun 2009
Location: Top of a Triangle
Posts: 3,009
Groaned at 42 Times in 33 Posts
Thanked 5,673 Times in 2,039 Posts
TidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond reputeTidakApa has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
Interesting, because I was told by a pilot and crew that I could not move before take off. Once the plane was in the air they didn't care where we sat. The reason is that the datum for the airplane is computed and if people move around it makes it harder for the pilot to safely take off and land.

That is why when you are taking off or getting ready for final approach they don't want you moving around.
The Clangers: You are very correct with "Weight and Balance" of the aircraft.

Weejeem: Thanks for your answer on the boiling water changing the sound pitch.
Reply With Quote
  #1116  
Old 28.06.2010, 22:08
Upthehatters2008's Avatar
Forum Legend
 
Join Date: May 2010
Location: In the kitchen at parties.
Posts: 4,579
Groaned at 212 Times in 126 Posts
Thanked 6,078 Times in 2,378 Posts
Upthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond repute
Re: Ask a Scientist

Anyone care to hypothesise on what would cause the anomaly around Southern India on this map of the distribution of gravity around the Earth ?

I haven't the foggiest yet...

Reply With Quote
  #1117  
Old 28.06.2010, 22:13
Upthehatters2008's Avatar
Forum Legend
 
Join Date: May 2010
Location: In the kitchen at parties.
Posts: 4,579
Groaned at 212 Times in 126 Posts
Thanked 6,078 Times in 2,378 Posts
Upthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
As the water temperature rises, the average number of hydrogen bonds between the water molecule gets progressively lower; i.e. there is a lowering of the viscosity of the liquid. This change in viscosity directly influences the size of the "lumps" that result as the liquid impacts on a surface, which in turn results in a different pitch.
Weaker or lower ? Surely if the number of bonds is reduced then the chemical properties change and you no longer have water but a mass of potentially explosive gases.., however if the covalent bond becomes weaker, the viscosity, as you quote will reduce...
Reply With Quote
  #1118  
Old 28.06.2010, 22:18
Dougal's Breakfast's Avatar
Forum Legend
 
Join Date: Nov 2007
Location: GL
Posts: 15,377
Groaned at 969 Times in 737 Posts
Thanked 38,592 Times in 12,093 Posts
Dougal's Breakfast has a reputation beyond reputeDougal's Breakfast has a reputation beyond reputeDougal's Breakfast has a reputation beyond reputeDougal's Breakfast has a reputation beyond reputeDougal's Breakfast has a reputation beyond reputeDougal's Breakfast has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
Anyone care to hypothesise on what would cause the anomaly around Southern India on this map of the distribution of gravity around the Earth ?

I haven't the foggiest yet...

I don't know the cause, but I've seen the effect:



Reply With Quote
  #1119  
Old 28.06.2010, 22:20
Upthehatters2008's Avatar
Forum Legend
 
Join Date: May 2010
Location: In the kitchen at parties.
Posts: 4,579
Groaned at 212 Times in 126 Posts
Thanked 6,078 Times in 2,378 Posts
Upthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond reputeUpthehatters2008 has a reputation beyond repute
Re: Ask a Scientist

Quote:
View Post
I don't know the cause, but I've seen the effect:



LOL ! Exactly what came to my mind for a very brief silly moment...

Then again
Reply With Quote
  #1120  
Old 29.06.2010, 09:55
Member
 
Join Date: Jun 2008
Location: zurich
Posts: 112
Groaned at 1 Time in 1 Post
Thanked 13 Times in 7 Posts
lokami has no particular reputation at present
Re: Ask a Scientist

Would it have anything to do with plate techtonics and India's fast movement away from Africa?
Reply With Quote
Reply

Tags
clean eating habits, nutella, say no to marmite




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Average salary for post-doctoral scientist barish Employment 87 01.10.2008 15:27
Wanted: Drug Metabolism Scientist to work in major Pharma, Basel Caroline Jobs wanted 0 20.09.2007 20:00
Surfing Scientist!!! Sarge Jobs wanted 2 24.05.2007 04:38


All times are GMT +2. The time now is 12:31.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.
LinkBacks Enabled by vBSEO 3.1.0