Tony Cooper <tonycooper214@gmail.com> wrote:

> News articles about the ship's collision with the Baltimore Key bridge
> have been referring to it as a "Black swan event". I had to look up
> that term:
>
> "The black swan theory or theory of black swan events is a metaphor
> that describes an event that comes as a surprise, has a major effect,
> and is often inappropriately rationalized after the fact with the
> benefit of hindsight."
>
> For a more detailed explantion:
>
> https://corporatefinanceinstitute.com/resources/economics/examples-of-blac
> k-swan-events/#:~:text=The%20Great%20Recession,been%20a%20booming%20housin
> g%20market.

For one it may be a 'black swan event'
for another it may be an accident waiting to happen.
For the USA in particular, with lots of flimsily built bridges
without adequate protection things like this happen regularly.
There isn't any need for container ships to make it happen either.

To refresh your memory, five years ago there was the
'Florida International University pedestrian bridge collapse',
as these distances go, almost in your backyard. (near Miami)
Six persons were killed, by coincidence the same number as in Baltimore.

Longer ago there was the Sunshine Skyway Bridge collapse,
also almost in your backyard (near Tampa, 1990)
Like in Tampa, this one collapsed after collision with a freighter.
(leaving 35 dead)

You should rename your 'black swans' to 'lame excuse swans',

Jan
(don't bother telling me how really big Florida is)

charles <charles@candehope.me.uk> wrote:

> In article <l7249cFlm7pU1@mid.individual.net>, Athel Cornish-Bowden
> <me@yahoo.com> wrote:
> > On 2024-04-02 10:00:03 +0000, charles said:
>
> > > In article <uugert$33gcv$1@dont-email.me>, Hibou
> > > <vpaereru-unmonitored@yahoo.com.invalid> wrote:
> > >> Le 01/04/2024 à 17:08, charles a écrit :
> > >>>
> > >>> we were shown the film of it during my Engineering degree, (1959-62)
> > >
> > >> There seem to be a lot of engineers in this forum.
> > >
> > >> Good chaps, engineers. The profession is one of the more honest. One
> > >> can fool people a lot of the time, but one can't fool Nature.
> > >
> > > we were also told that when concrete was first used as a structural
> > > product. all the experimental data showed it was equal in compression
> > > and tension. Funnily enough, the early bridges fell down ;-(
>
> > Not the ones built by the Romans! The viaduct in Segovia is in almost as
> > good condition today as it was 2000 years ago.
>
> according to Wiki that viaduct is made of unmortared granite blocks - not
> concrete.

Which makes it all the more surprising,
and even more of a great engineering achievement.
Have you noticed how tall and slim the structure is?
And it isn't a one of a kind,
there may be hundreds of km in all of surviving Roman aquaduct.
Most of the damage to them has been deliberately caused.
Some have functioned, after some restoration, even in modern times,

Jan

Hibou <vpaereru-unmonitored@yahoo.com.invalid> wrote:

> Le 31/03/2024 à 06:08, Peter Moylan a écrit :
> > On 31/03/24 15:00, Tony Cooper wrote:
> >>
> >> News articles about the ship's collision with the Baltimore Key bridge
> >> have been referring to it as a "Black swan event". I had to look up
> >> that term:
> >>
> >> "The black swan theory or theory of black swan events is a metaphor
> >> that describes an event that comes as a surprise, has a major effect,
> >> and is often inappropriately rationalized after the fact with the
> >> benefit of hindsight."
> >>
> >> For a more detailed explantion:
> >>
> >> https://corporatefinanceinstitute.com/resources/economics/examples-of-black
-swan-events/#:~:text=The%20Great%20Recession,been%20a%20booming%20housing%20market.
> >
> > Interesting. I suppose the Australian finance people call it a white
> > swan event.
>
> A few days ago, a chap on France Info - Michel Virlogeux, designer of
> the Pont de Normandie - was saying that this kind of accident is bound
> to happen, and that bridge design should take that into account.
>
> Let me search a bit - yes, here it is - 26th March:
>
> « Alors évidemment, ce n'est pas tous les jours, mais c'est un type
> d'accident qui est relativement classique. Le pont de Normandie que j'ai
> construit a été conçu pour se mettre à l'abri de ce genre de chose en
> mettant les piles en dehors de la rivière. Vous avez un pylône qui est
> sur la rive gauche, à terre, un pylône vers la rive droite, le long de
> la digue, protégé par une enceinte de protection pour le cas où des
> bateaux s'écarteraient très largement du chenal de navigation » -
> <https://www.francetvinfo.fr/monde/usa/pont-de-baltimore-effondre-il-n-y-a-auc
une-chance-qu-une-pile-de-pont-puisse-resister-a-un-tel-choc-selon-le-concepteur-du-pont-de-normandie_6448750.html>
>
> So just bad design, then. An accident waiting to happen.

Yes. A simple order of magnitude estimate for a drifting ship
gives forces of the order of 10 MN,
or in geriatric units 1000 tons(force) aka a million kgF.
(acting for perhaps 10 seconds)

Only a large island-like structure will do for protection,
like at the Pont de Normandie,

Jan

charles <charles@candehope.me.uk> wrote:

> In article <uugert$33gcv$1@dont-email.me>,
> Hibou <vpaereru-unmonitored@yahoo.com.invalid> wrote:
> > Le 01/04/2024 à 17:08, charles a écrit :
> > >
> > > we were shown the film of it during my Engineering degree, (1959-62)
>
> > There seem to be a lot of engineers in this forum.
>
> > Good chaps, engineers. The profession is one of the more honest. One can
> > fool people a lot of the time, but one can't fool Nature.
>
> we were also told that when concrete was first used as a structural
> product. all the experimental data showed it was equal in compression and
> tension.

Not really. You are inventing things that never were.

> Funnily enough, the early bridges fell down ;-(

So next they invented pre-stressed concrete. [1]

Jan

[1] Which is fine, but it really needs good maintenance.

Le 02/04/2024 à 09:27, Athel Cornish-Bowden a écrit :
> On 2024-04-02 08:15:57 +0000, Hibou said:
>> Le 01/04/2024 à 17:08, charles a écrit :
>>>
>>> we were shown the film of it during my Engineering degree, (1959-62)
>>
>> There seem to be a lot of engineers in this forum.
>>
>> Good chaps, engineers. The profession is one of the more honest. One
>> can fool people a lot of the time, but one can't fool Nature.
>
> Maybe, but the chaps who built the bridge in Baltimore thought they could.

Perhaps I should nuance a bit. The world compels engineers to honesty in
a way that it doesn't with many others - ministers of religion,
politicians, advertisers..., who can forge careers in which truth has
little part. That's not to say that all engineers are good or honest,
just that on average they have to be quite good and quite honest. In
this they are like others who have to answer to the real world -
architects, scientists, craftsmen....

The bridge collapse in Baltimore is reality having its say. For all I
know its engineer may have wanted to do a better job, but been overruled
for cost reasons. I dare say the inquiry will find out. Unfortunately,
this failure has come late and cost lives. Most engineering mistakes are
found and corrected in the development lab.

Finally, I should declare bias. I'm an engineer myself, spent many years
in electronics R and D. I've seen some bad designs in my time; I just
hope I haven't left any behind me.

On 2024-04-02 11:00:03 +0000, charles said:

> In article <l7249cFlm7pU1@mid.individual.net>, Athel Cornish-Bowden
> <me@yahoo.com> wrote:
>> On 2024-04-02 10:00:03 +0000, charles said:
>
>>> In article <uugert$33gcv$1@dont-email.me>, Hibou
>>> <vpaereru-unmonitored@yahoo.com.invalid> wrote:
>>>> Le 01/04/2024 à 17:08, charles a écrit :
>>>>>
>>>>> we were shown the film of it during my Engineering degree, (1959-62)
>>>
>>>> There seem to be a lot of engineers in this forum.
>>>
>>>> Good chaps, engineers. The profession is one of the more honest. One
>>>> can fool people a lot of the time, but one can't fool Nature.
>>>
>>> we were also told that when concrete was first used as a structural
>>> product. all the experimental data showed it was equal in compression
>>> and tension. Funnily enough, the early bridges fell down ;-(
>
>> Not the ones built by the Romans! The viaduct in Segovia is in almost as
>> good condition today as it was 2000 years ago.
>
> according to Wiki that viaduct is made of unmortared granite blocks - not
> concrete.

Yes indeed, but I took your "the early bridges" to refer to early
bridges in general, not specifically to ones made of concrete. Roman
concrete was also impressively durable. The bridge at the Barbegal mill
outside Arles was made of concrete and is still standing.

Many of the Roman remains that have deteriorated did so not so much
because they didn't stand up to Nature, but because chaps in the Middle
Ages took bits to build other things. They couldn't that with the
viaduct of Segovia because one would modern explosives to take it apart.

--
Athel -- French and British, living in Marseilles for 37 years; mainly
in England until 1987.

On 02 Apr 2024, Athel Cornish-Bowden wrote

> On 2024-04-02 11:00:03 +0000, charles said:
>
>> In article <l7249cFlm7pU1@mid.individual.net>, Athel
>> Cornish-Bowden <me@yahoo.com> wrote:
>>> On 2024-04-02 10:00:03 +0000, charles said:
>>
>>>> In article <uugert$33gcv$1@dont-email.me>, Hibou
>>>> <vpaereru-unmonitored@yahoo.com.invalid> wrote:
>>>>> Le 01/04/2024 à 17:08, charles a écrit :
>>>>>>
>>>>>> we were shown the film of it during my Engineering degree,
>>>>>> (1959-62)
>>>>
>>>>> There seem to be a lot of engineers in this forum.
>>>>
>>>>> Good chaps, engineers. The profession is one of the more
>>>>> honest. One can fool people a lot of the time, but one can't
>>>>> fool Nature.
>>>>
>>>> we were also told that when concrete was first used as a
>>>> structural product. all the experimental data showed it was
>>>> equal in compression and tension. Funnily enough, the early
>>>> bridges fell down ;-(
>>
>>> Not the ones built by the Romans! The viaduct in Segovia is in
>>> almost as good condition today as it was 2000 years ago.
>>
>> according to Wiki that viaduct is made of unmortared granite
>> blocks - not concrete.
>
> Yes indeed, but I took your "the early bridges" to refer to early
> bridges in general, not specifically to ones made of concrete.
> Roman concrete was also impressively durable. The bridge at the
> Barbegal mill outside Arles was made of concrete and is still
> standing.
>
> Many of the Roman remains that have deteriorated did so not so
> much because they didn't stand up to Nature, but because chaps in
> the Middle Ages took bits to build other things. They couldn't
> that with the viaduct of Segovia because one would modern
> explosives to take it apart.

Re: the longevity of Roman concrete, the dome of the Pantheon is
something like 1,900 years old and intact.

--
Cheers, Harvey

Hibou <vpaereru-unmonitored@yahoo.com.invalid> wrote:

> Le 02/04/2024 à 09:27, Athel Cornish-Bowden a écrit :
> > On 2024-04-02 08:15:57 +0000, Hibou said:
> >> Le 01/04/2024 à 17:08, charles a écrit :
> >>>
> >>> we were shown the film of it during my Engineering degree, (1959-62)
> >>
> >> There seem to be a lot of engineers in this forum.
> >>
> >> Good chaps, engineers. The profession is one of the more honest. One
> >> can fool people a lot of the time, but one can't fool Nature.
> >
> > Maybe, but the chaps who built the bridge in Baltimore thought they could.
>
> Perhaps I should nuance a bit. The world compels engineers to honesty in
> a way that it doesn't with many others - ministers of religion,
> politicians, advertisers..., who can forge careers in which truth has
> little part. That's not to say that all engineers are good or honest,
> just that on average they have to be quite good and quite honest. In
> this they are like others who have to answer to the real world -
> architects, scientists, craftsmen....
>
> The bridge collapse in Baltimore is reality having its say. For all I
> know its engineer may have wanted to do a better job, but been overruled
> for cost reasons. I dare say the inquiry will find out. Unfortunately,
> this failure has come late and cost lives. Most engineering mistakes are
> found and corrected in the development lab.
>
> Finally, I should declare bias. I'm an engineer myself, spent many years
> in electronics R and D. I've seen some bad designs in my time; I just
> hope I haven't left any behind me.

It was hardly news.
They had a very similar bridge collapse in Florida in 1990,
on a rather similar bridge, and for just the same reason.
Forty years should have been time enough to retrofit protection,

Jan

Hibou <vpaereru-unmonitored@yahoo.com.invalid> wrote:

> Le 01/04/2024 à 17:08, charles a écrit :
> >
> > we were shown the film of it during my Engineering degree, (1959-62)
>
> There seem to be a lot of engineers in this forum.
>
> Good chaps, engineers. The profession is one of the more honest. One can
> fool people a lot of the time, but one can't fool Nature.

Dixit Richard Feynman,

Jan

--
"For a successful technology, reality must take precedence over public
relations, for nature cannot be fooled." (Richard Feynman)

HVS <office@REMOVETHISwhhvs.co.uk> wrote:

> On 02 Apr 2024, Athel Cornish-Bowden wrote
>
> > On 2024-04-02 11:00:03 +0000, charles said:
> >
> >> In article <l7249cFlm7pU1@mid.individual.net>, Athel
> >> Cornish-Bowden <me@yahoo.com> wrote:
> >>> On 2024-04-02 10:00:03 +0000, charles said:
> >>
> >>>> In article <uugert$33gcv$1@dont-email.me>, Hibou
> >>>> <vpaereru-unmonitored@yahoo.com.invalid> wrote:
> >>>>> Le 01/04/2024 à 17:08, charles a écrit :
> >>>>>>
> >>>>>> we were shown the film of it during my Engineering degree,
> >>>>>> (1959-62)
> >>>>
> >>>>> There seem to be a lot of engineers in this forum.
> >>>>
> >>>>> Good chaps, engineers. The profession is one of the more
> >>>>> honest. One can fool people a lot of the time, but one can't
> >>>>> fool Nature.
> >>>>
> >>>> we were also told that when concrete was first used as a
> >>>> structural product. all the experimental data showed it was
> >>>> equal in compression and tension. Funnily enough, the early
> >>>> bridges fell down ;-(
> >>
> >>> Not the ones built by the Romans! The viaduct in Segovia is in
> >>> almost as good condition today as it was 2000 years ago.
> >>
> >> according to Wiki that viaduct is made of unmortared granite
> >> blocks - not concrete.
> >
> > Yes indeed, but I took your "the early bridges" to refer to early
> > bridges in general, not specifically to ones made of concrete.
> > Roman concrete was also impressively durable. The bridge at the
> > Barbegal mill outside Arles was made of concrete and is still
> > standing.
> >
> > Many of the Roman remains that have deteriorated did so not so
> > much because they didn't stand up to Nature, but because chaps in
> > the Middle Ages took bits to build other things. They couldn't
> > that with the viaduct of Segovia because one would modern
> > explosives to take it apart.
>
> Re: the longevity of Roman concrete, the dome of the Pantheon is
> something like 1,900 years old and intact.

That one is reinforced concrete even.
Not with steel, but with embedded strips of tile.
And it is just too big to vandalise,

Jan

On 02/04/24 23:08, Hibou wrote:
> Le 02/04/2024 à 09:27, Athel Cornish-Bowden a écrit :
>> On 2024-04-02 08:15:57 +0000, Hibou said:
>>> Le 01/04/2024 à 17:08, charles a écrit :
>>>>
>>>> we were shown the film of it during my Engineering degree,
>>>> (1959-62)
>>>
>>> There seem to be a lot of engineers in this forum.
>>>
>>> Good chaps, engineers. The profession is one of the more honest.
>>> One can fool people a lot of the time, but one can't fool
>>> Nature.
>>
>> Maybe, but the chaps who built the bridge in Baltimore thought they
>> could.
>
> Perhaps I should nuance a bit. The world compels engineers to honesty
> in a way that it doesn't with many others - ministers of religion,
> politicians, advertisers..., who can forge careers in which truth has
> little part. That's not to say that all engineers are good or
> honest, just that on average they have to be quite good and quite
> honest. In this they are like others who have to answer to the real
> world - architects, scientists, craftsmen....

It's a question of motivation. Engineers who screw up will damage their
own reputations, so there are positive reasons for doing an honest job.
In politics and some other callings, dishonesty is a career-advancing
quality.

--
Peter Moylan http://www.pmoylan.org
Newcastle, NSW

On 02-Apr-24 23:18, Peter Moylan wrote:
> On 02/04/24 23:08, Hibou wrote:
>> Le 02/04/2024 à 09:27, Athel Cornish-Bowden a écrit :
>>> On 2024-04-02 08:15:57 +0000, Hibou said:
>>>> Le 01/04/2024 à 17:08, charles a écrit :
>>>>>
>>>>> we were shown the film of it during my Engineering degree,
>>>>> (1959-62)
>>>>
>>>> There seem to be a lot of engineers in this forum.
>>>>
>>>> Good chaps, engineers. The profession is one of the more honest.
>>>> One can fool people a lot of the time, but one can't fool
>>>> Nature.
>>>
>>> Maybe, but the chaps who built the bridge in Baltimore thought they
>>>  could.
>>
>> Perhaps I should nuance a bit. The world compels engineers to honesty
>> in a way that it doesn't with many others - ministers of religion,
>> politicians, advertisers..., who can forge careers in which truth has
>>  little part. That's not to say that all engineers are good or
>> honest, just that on average they have to be quite good and quite
>> honest. In this they are like others who have to answer to the real
>> world - architects, scientists, craftsmen....
>
> It's a question of motivation. Engineers who screw up will damage their
> own reputations, so there are positive reasons for doing an honest job.
> In politics and some other callings, dishonesty is a career-advancing
> quality.
>
Governing parties which anticipate losing at the next election 'have
been known' to screw up the economy in ways that will cause great
headaches for the incoming party[1].
I can't quite see engineers doing that.

[1] Perhaps they have watched too many snooker matches?

--
Sam Plusnet

Sam Plusnet wrote:

> Governing parties which anticipate losing at the next election 'have
> been known' to screw up the economy in ways that will cause great
> headaches for the incoming party[1].
> I can't quite see engineers doing that.

Are there many cases where one engineer has taken over from another one
on the same project?

In the case of Sydney Opera it was actually reversed. The ones that took
over, screwed up the job after Jørn Utzon.

--
Bertel, Denmark

On 2024-04-03 10:13:29 +0000, Bertel Lund Hansen said:

> Sam Plusnet wrote:
>
>> Governing parties which anticipate losing at the next election 'have
>> been known' to screw up the economy in ways that will cause great
>> headaches for the incoming party[1].
>> I can't quite see engineers doing that.
>
> Are there many cases where one engineer has taken over from another one
> on the same project?

I don't know, but last night we watched "Un autre monde" (with Vincent
Lindon and Sandrine Kiberlain). OK, but a bit depressing. It
illustrated the idea that senior management sometimes think that the
way to bring a factory back to profitability is to get rid of many of
the engineers.
>
> In the case of Sydney Opera it was actually reversed. The ones that took
> over, screwed up the job after Jørn Utzon.

--
Athel -- French and British, living in Marseilles for 37 years; mainly
in England until 1987.

Le 03/04/2024 à 11:13, Bertel Lund Hansen a écrit :
> Sam Plusnet wrote:
>>
>> Governing parties which anticipate losing at the next election 'have
>> been known' to screw up the economy in ways that will cause great
>> headaches for the incoming party[1].
>> I can't quite see engineers doing that.
>
> Are there many cases where one engineer has taken over from another one
> on the same project?
>
> In the case of Sydney Opera it was actually reversed. The ones that took
> over, screwed up the job after Jørn Utzon.

Where I worked, it happened fairly often. People move on to other
projects, contractors do a job that is then passed to permanent staff...
(and the contractor is then unavailable to answer questions).

Personally, I found it difficult to take over someone else's work.
People think in different ways, have different styles when drawing
circuits and writing software, which are not always easy to unravel.
Original designers have had a lot of thoughts along the way, and these
are not always recorded in their logbooks, so the hapless inheritor is
unaware of them.

I don't think I was alone. An engineer who inherited some software from
me, in which I'd been having fun with recursion, complained that I must
have been on drugs when I wrote it.

On 2024-04-03 10:41:49 +0000, Hibou said:

> Le 03/04/2024 à 11:13, Bertel Lund Hansen a écrit :
>> Sam Plusnet wrote:
>>>
>>> Governing parties which anticipate losing at the next election 'have
>>> been known' to screw up the economy in ways that will cause great
>>> headaches for the incoming party[1].
>>> I can't quite see engineers doing that.
>>
>> Are there many cases where one engineer has taken over from another one
>> on the same project?
>>
>> In the case of Sydney Opera it was actually reversed. The ones that took
>> over, screwed up the job after Jørn Utzon.
>
> Where I worked, it happened fairly often. People move on to other
> projects, contractors do a job that is then passed to permanent
> staff... (and the contractor is then unavailable to answer questions).
>
> Personally, I found it difficult to take over someone else's work.
> People think in different ways, have different styles when drawing
> circuits and writing software, which are not always easy to unravel.
> Original designers have had a lot of thoughts along the way, and these
> are not always recorded in their logbooks, so the hapless inheritor is
> unaware of them.
>
> I don't think I was alone. An engineer who inherited some software from
> me, in which I'd been having fun with recursion, complained that I must
> have been on drugs when I wrote it.

I agree with your inheritor.

--
Athel -- French and British, living in Marseilles for 37 years; mainly
in England until 1987.

On 2024-03-31, Ross Clark wrote:

> On 31/03/2024 5:00 p.m., Tony Cooper wrote:
>> News articles about the ship's collision with the Baltimore Key bridge
>> have been referring to it as a "Black swan event". I had to look up
>> that term:
>>
>> "The black swan theory or theory of black swan events is a metaphor
>> that describes an event that comes as a surprise, has a major effect,
>> and is often inappropriately rationalized after the fact with the
>> benefit of hindsight."
>>
>> For a more detailed explantion:
>>
>> https://corporatefinanceinstitute.com/resources/economics/examples-of-black-swan-events/#:~:text=The%20Great%20Recession,been%20a%20booming%20housing%20market.
>>
>>
>
> OED:
> black swan (proverbial) something extremely rare (or non-existent); a
> rarity, _rara avis_.
> (examples from late 1500s)

One of the amusing translation exercises in _Latin for People_ starts
out "Ursus in tabernam introiit et cerevisiam imperāvit." I can't
remember much of it in Latin, but the bartender runs to the owner, who
tells him to sell the bear a beer but charge him double. In the end,
the bartender says "ursī rārae avēs in tabernā" and the bear says it's
not surprising given the high price of beer.

--
Logic is the beginning of wisdom, not the end.
---Spock

Adam Funk <a24061@ducksburg.com> wrote or quoted:
>tells him to sell the bear a beer but charge him double. In the end,
>the bartender says "ursī rārae avēs in tabernā" and the bear says it's
>not surprising given the high price of beer.

Yeah, but really the high price should keep everyone equally
from going to this bar, not just bears in particular.

ram@zedat.fu-berlin.de (Stefan Ram) wrote or quoted:
>Adam Funk <a24061@ducksburg.com> wrote or quoted:
>>tells him to sell the bear a beer but charge him double. In the end,
>>the bartender says "ursī rārae avēs in tabernā" and the bear says it's
>>not surprising given the high price of beer.
>Yeah, but really the high price should keep everyone equally
>from going to this bar, not just bears in particular.

Aw jeez, I didn't realize they jacked up the price
on just that one bear so much. My bad!

Le 03/04/2024 à 11:47, Athel Cornish-Bowden a écrit :
> On 2024-04-03 10:41:49 +0000, Hibou said:
>>
>> I don't think I was alone. An engineer who inherited some software
>> from me, in which I'd been having fun with recursion, complained that
>> I must have been on drugs when I wrote it.
>
> I agree with your inheritor.

<Smile>

Rich Ulrich <rich.ulrich@comcast.net> wrote:

> On Sun, 31 Mar 2024 00:00:53 -0400, Tony Cooper
> <tonycooper214@gmail.com> wrote:
>
> >News articles about the ship's collision with the Baltimore Key bridge
> >have been referring to it as a "Black swan event". I had to look up
> >that term:
> >
> >"The black swan theory or theory of black swan events is a metaphor
> >that describes an event that comes as a surprise, has a major effect,
> >and is often inappropriately rationalized after the fact with the
> >benefit of hindsight."
> >
> >For a more detailed explantion:
> >
> >https://corporatefinanceinstitute.com/resources/economics/examples-of-black-s
wan-events/#:~:text=The%20Great%20Recession,been%20a%20booming%20housing%20market.
> >
>
> The metaphor might be a bit familiar because there was a
> book by that name, 2007.
> The Black Swan: The Impact of the Highly Improbable is a 2007 book
> by Nassim Nicholas Taleb, who is a former options trader. The book
> focuses on the extreme impact of rare and unpredictable outlier
> events—and the human tendency to find simplistic explanations for
> these events, retrospectively. Wikipedia
>
> I read the book back then, or else I read a long discussion of it.

Yes, I have it, but didn't really bring myself to read it.
The problem with it is that it states correctly
that 'Black Swans" will blow away many predictions and expectations.
(the author thinks almost all of them)
That said, what can you do about it?
(except for being more modest)

But whatever, all this is rather irrelevant,
because that ship taking down that bridge
certainly wasn't a black swan event.

It could, and should have been foreseen,
and something should and could have been done about it.

In general: Getting hurt in a repeated game of Russian roulette
is not a "Black Swan" event,

Jan

Ross Clark <benlizro@ihug.co.nz> wrote:

> On 31/03/2024 7:00 p.m., Hibou wrote:
> > Le 31/03/2024 à 06:08, Peter Moylan a écrit :
> >> On 31/03/24 15:00, Tony Cooper wrote:
> >>>
> >>> News articles about the ship's collision with the Baltimore Key bridge
> >>> have been referring to it as a "Black swan event". I had to look up
> >>> that term:
> >>>
> >>> "The black swan theory or theory of black swan events is a metaphor
> >>> that describes an event that comes as a surprise, has a major effect,
> >>> and is often inappropriately rationalized after the fact with the
> >>> benefit of hindsight."
> >>>
> >>> For a more detailed explantion:
> >>>
> >>> https://corporatefinanceinstitute.com/resources/economics/examples-of-blac
k-swan-events/#:~:text=The%20Great%20Recession,been%20a%20booming%20housing%20market.
> >>>
> >>
> >> Interesting. I suppose the Australian finance people call it a white
> >> swan event.
> >
> > A few days ago, a chap on France Info - Michel Virlogeux, designer of
> > the Pont de Normandie - was saying that this kind of accident is bound
> > to happen, and that bridge design should take that into account.
> >
> > Let me search a bit - yes, here it is - 26th March:
> >
> > « Alors évidemment, ce n'est pas tous les jours, mais c'est un type
> > d'accident qui est relativement classique. Le pont de Normandie que j'ai
> > construit a été conçu pour se mettre à l'abri de ce genre de chose en
> > mettant les piles en dehors de la rivière. Vous avez un pylône qui est
> > sur la rive gauche, à terre, un pylône vers la rive droite, le long de
> > la digue, protégé par une enceinte de protection pour le cas où des
> > bateaux s'écarteraient très largement du chenal de navigation » -
> > <https://www.francetvinfo.fr/monde/usa/pont-de-baltimore-effondre-il-n-y-a-a
ucune-chance-qu-une-pile-de-pont-puisse-resister-a-un-tel-choc-selon-le-concepteur-du-pont-de-normandie_6448750.html>
> >
> >
> > So just bad design, then. An accident waiting to happen.
> >
>
> Within hours of the event, looking around for information, I saw a clip
> of a civil engineer from New Jersey being interviewed, explaining that,
> yes, there were ways to protect a bridge against this sort of accident,
> and describing a "fendering structure" (I think those were his words)
> which would absorb much of the impact.
> So everybody knew.

Yes. Or even better: why build a huge container terminal
behind a vulnerable bridge?

Jan

On 2024-04-03 12:20:42 +0000, J. J. Lodder said:

> Ross Clark <benlizro@ihug.co.nz> wrote:
>
>> On 31/03/2024 7:00 p.m., Hibou wrote:
>>> Le 31/03/2024 à 06:08, Peter Moylan a écrit :
>>>> On 31/03/24 15:00, Tony Cooper wrote:
>>>>>
>>>>> News articles about the ship's collision with the Baltimore Key bridge
>>>>> have been referring to it as a "Black swan event". I had to look up
>>>>> that term:
>>>>>
>>>>> "The black swan theory or theory of black swan events is a metaphor
>>>>> that describes an event that comes as a surprise, has a major effect,
>>>>> and is often inappropriately rationalized after the fact with the
>>>>> benefit of hindsight."
>>>>>
>>>>> For a more detailed explantion:
>>>>>
>>>>> https://corporatefinanceinstitute.com/resources/economics/examples-of-blac
> k-swan-events/#:~:text=The%20Great%20Recession,been%20a%20booming%20housing%20market.
>
>>>>>
>>>>
>>>> Interesting. I suppose the Australian finance people call it a white
>>>> swan event.
>>>
>>> A few days ago, a chap on France Info - Michel Virlogeux, designer of
>>> the Pont de Normandie - was saying that this kind of accident is bound
>>> to happen, and that bridge design should take that into account.
>>>
>>> Let me search a bit - yes, here it is - 26th March:
>>>
>>> « Alors évidemment, ce n'est pas tous les jours, mais c'est un type
>>> d'accident qui est relativement classique. Le pont de Normandie que j'ai
>>> construit a été conçu pour se mettre à l'abri de ce genre de chose en
>>> mettant les piles en dehors de la rivière. Vous avez un pylône qui est
>>> sur la rive gauche, à terre, un pylône vers la rive droite, le long de
>>> la digue, protégé par une enceinte de protection pour le cas où des
>>> bateaux s'écarteraient très largement du chenal de navigation » -
>>> <https://www.francetvinfo.fr/monde/usa/pont-de-baltimore-effondre-il-n-y-a-a
> ucune-chance-qu-une-pile-de-pont-puisse-resister-a-un-tel-choc-selon-le-concepteur-du-pont-de-normandie_6448750.html>
>
>>>
>>>
>>> So just bad design, then. An accident waiting to happen.
>>>
>>
>> Within hours of the event, looking around for information, I saw a clip
>> of a civil engineer from New Jersey being interviewed, explaining that,
>> yes, there were ways to protect a bridge against this sort of accident,
>> and describing a "fendering structure" (I think those were his words)
>> which would absorb much of the impact.
>> So everybody knew.
>
> Yes. Or even better: why build a huge container terminal
> behind a vulnerable bridge?

They wanted the money.

> --
Athel -- French and British, living in Marseilles for 37 years; mainly
in England until 1987.

On 01/04/2024 17:42, Athel Cornish-Bowden wrote:
> On 2024-04-01 15:24:53 +0000, Garrett Wollman said:
>
>> In article <uudj7n$2b3sn$1@dont-email.me>,
>> Hibou  <vpaereru-unmonitored@yahoo.com.invalid> wrote:
>>> Le 31/03/2024 à 23:40, Garrett Wollman a écrit :
>>>> I noted elsewhere that for most of the 20th century, American civil
>>>> engineers were prejudiced against cable-stayed bridges, which were
>>>> common in Europe during the post-WW2 reconstruction due to their
>>>> economy of construction.  This didn't start to shift until the late
>>>> 1980s.
>>>
>>> Galloping Gertie! one might say.
>>
>> The Tacoma Narrows Bridge was a suspension bridge, of course, and not
>> a cable-stayed bridge.
>
> At one time that was the film I'd seen for the largest number of times.
>
>

I can't see you finishing your popcorn to that film. How long is it, a
minute or two?

On 2024-04-03, Stefan Ram wrote:

> ram@zedat.fu-berlin.de (Stefan Ram) wrote or quoted:
>>Adam Funk <a24061@ducksburg.com> wrote or quoted:
>>>tells him to sell the bear a beer but charge him double. In the end,
>>>the bartender says "ursī rārae avēs in tabernā" and the bear says it's
>>>not surprising given the high price of beer.
>>Yeah, but really the high price should keep everyone equally
>>from going to this bar, not just bears in particular.
>
> Aw jeez, I didn't realize they jacked up the price
> on just that one bear so much. My bad!

I just found it in the book & it doesn't say double.

The owner says "Ursō cerevisiam vendere potes et, quia ursī stultī
sunt, dīcere potes etiam: 'Pretium sēstertium.'" ("You can sell the
bear a beer but, because bears are stupid, tell him the price is a
sestertium." The vocabulary for that chapter says a sestertium was
worth ~$75. The book was published in 1976.)

--
FORTRAN: You shoot yourself in each toe, iteratively, until you run
out of toes, then you read in the next foot and repeat. If you run out
of bullets, you continue anyway because you have no exception-handling
facility.