Using Spice to verify a circuit works

[Jan Panteltje]

On a sunny day (Tue, 18 Jun 2019 10:09:06 -0700) it happened John Larkin
<jjlarkin@highland_snip_technology.com> wrote in
<1f6ige54rnmk41ftnp4oribjonc61dvl7h@4ax.com>:

On Tue, 18 Jun 2019 15:42:01 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Tue, 18 Jun 2019 07:04:12 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
6mrhge59b3k4a67k83rv1lqp8bnv57s0l7@4ax.com>:

On Tue, 18 Jun 2019 04:19:24 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Mon, 17 Jun 2019 21:49:17 -0400) it happened bitrex
user@example.net> wrote in <yqXNE.41731$IQ6.21299@fx09.iad>:

The 737 Max handled very much like a 737 there were not huge engineering
surprises there. It was just different enough that they wanted to avoid
a different type rating. It was more of a bean-counting problem than an
engineering problem.

No, that plane is unstable by nature due to the position of the engines if I understand it right.
They wanted to fix that with some software.
That worked, then they 'simplified' the software, removed a G sensor, and that did not work.
The basic plane designs sucks.
A good plane flight strait without correction.

If you make a paper airplane, and it is bad, it will do strange things,
you could than add all sorts of systems to make it fly right
but it would still be a POS.

Just like the F35.

The F35 will be OK. Fighter planes don't dogfight any more. F35 is an
electronics and missile platform.

We have those on order, there was one here last year,
and really, going by the sound I thought one flew over here yesterday.
There are 'air force days' somewhere not so far away, sort of where people can go
and look what's there, not in the airport close to here this year.
Anyways, F35 is not stealth, it is not stealth in the IR and it is not stealth in low frequency radar.
It is also detectable by passive radar (via radio and TV station reflections, so also low frequency).
It is a bad fighter, has only one engine (so more easily shot down),
about everything you can think of in that thing is *wrong* including that fan for VTOL in some models.

Aircraft carriers are big billion-dollar targets. Vertical takeoff and
land lets small ships become carriers. Or any field or parking lot
become an airport.

the UK had a nice one:
https://en.wikipedia.org/wiki/Harrier_Jump_Jet
them downgrading to a F35 would be a pity.

What the electronics in it does I have no idea, but it cannot make it fly better.
It is a taxpayer payed scam.


I suspect that manned fighter planes and bombers will be obsolete soon
anyhow.

Perhaps, sure missiles, rail-guns, lasers, what have you these days, will also be used.
In a real global nuclear war after the first exchange not much will fly I'd think, but I could be wrong.
For smaller scale conflicts it may or may not work,
I like the F16 a lot better.

And the other side MIGs, do not know what China has..
But China invented the gunpowder and had rockets before any of us westerns,
so who knows what they can come up with, now they already can shoot down sats.


China is struggling to build commercial planes and especially
struggling to build jet engines. The engines are really hard.

Yes, but they have great connections with Russia, and Russia has that experience,

I think China loves to jump into that market and get FAA approval,
would flying with Russian engines be a problem?
Just wondering...

 

[bitrex]

On 6/18/19 11:11 AM, John Larkin wrote:

On Tue, 18 Jun 2019 05:01:59 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Tue, 18 Jun 2019 00:37:50 -0400) it happened bitrex
user@example.net> wrote in <zUZNE.59350$935.48043@fx46.iad>:

On 6/18/19 12:19 AM, Jan Panteltje wrote:
On a sunny day (Mon, 17 Jun 2019 21:49:17 -0400) it happened bitrex
user@example.net> wrote in <yqXNE.41731$IQ6.21299@fx09.iad>:

The 737 Max handled very much like a 737 there were not huge engineering
surprises there. It was just different enough that they wanted to avoid
a different type rating. It was more of a bean-counting problem than an
engineering problem.

No, that plane is unstable by nature due to the position of the engines if I understand it right.
They wanted to fix that with some software.
That worked, then they 'simplified' the software, removed a G sensor, and that did not work.
The basic plane designs sucks.
A good plane flight strait without correction.

If you make a paper airplane, and it is bad, it will do strange things,
you could than add all sorts of systems to make it fly right
but it would still be a POS.

Just like the F35.


I don't believe it was dynamically unstable inherently like some (most?)
modern military combat aircraft are.

Toss it like a glider with no electronic flight controls, trimmed for
level flight, and it will probably enter a phugoid like most (all?)
large passenger aircraft do.

From what I have read, increasing engine power with the new engine positions
gave it a tendency to stall.
They moved the engine position to get better fuel efficiency?

More fuel-efficient engines have giant fans, and they would scrape the
ground. Landing gear was extended as far as practical, and then the
engine was moved forward and up. Airbus did similar things.

Moving the engine changed flight dynamics and introduced a hazard,
which Boeing fixed with software, badly.

Most planes nowadays have computer based "flight laws" that stabilze
things. Airbus planes are flown with a joystick that inputs data to a
computer.

Space shuttle orbiter was dynamically unstable. Turn off the computers
at 40k feet and it heads straight for the ground like a lawn dart. Can't
just "trim" it and let it glide forget it.

It still handled and fell like a brick with wings at low altitude with
feedback loops constantly working to stabilize it but enough not like a
lawn dart to make it landable.

 

[bitrex]

On 6/18/19 11:14 AM, John Larkin wrote:

On Mon, 17 Jun 2019 20:17:29 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:

On Mon, 17 Jun 2019 21:41:09 -0400, bitrex <user@example.net> wrote:

On 6/17/19 8:29 PM, Tom Gardner wrote:
Nobody in their right mind would sign-off a complex circuit
solely on the basis of a spice simulation. But Boeing is
planning on doing the equivalent for their 777X!

 "Specifically, Boeing is “reducing the scope and duration
 of certain costly physical tests used to certify the
 planemaker’s new aircraft,” Reuters reported over the
 weekend.
 We're thus told that engineers working on Boeing's new
 777X airliner project are intending to use computer
 simulations instead of real-world flight tests to
 validate their engineering decisions."

What could possibly go wrong with that?

https://www.theregister.co.uk/2019/06/17/boeing_certification_simulation_tests/


https://www.reuters.com/article/us-france-airshow-boeing-certification-e/exclusive-boeing-seeking-to-reduce-scope-duration-of-some-physical-tests-for-new-aircraft-sources-idUSKCN1TH0A3


Boeing hasn't started a clean-sheet design in decades and they'll likely
be selling variants of the 737 through the year 2080 so it'll probably
be OK.

They will start on the NMA, the New Midrange Aircraft, in the next few
years. The CEO just said so in an interview with Aviation Week.

Just read that they expect it to be in service in 2025.

the audio industry tends to be a world of incremental improvements
rather than revolutions. The average "workstation synthesizer" synthesis
engine tends to have a lifespan of a decade. Many variations and updates
and "Special Editions" and "Extreme Editions" are manufactured at
various price points.

Products are released in 2019 that cost the better part of $4000 and
have a 3" non-touch-sensitive display and 384 megabytes of editing
memory and the reviewers will gush about how revolutionary it all is.
The polyphony has been upgraded from 64 to 72. amazingggg

People try clean-sheet totally radical new designs from time to time and
musicians mostly sulk and complain it doesn't sound like the good ol' days.

 

On Tue, 18 Jun 2019 10:09:06 -0700, John Larkin
<jjlarkin@highland_snip_technology.com> wrote:

Just like the F35.

The F35 will be OK. Fighter planes don't dogfight any more. F35 is an
electronics and missile platform.

We have those on order, there was one here last year,
and really, going by the sound I thought one flew over here yesterday.
There are 'air force days' somewhere not so far away, sort of where people can go
and look what's there, not in the airport close to here this year.
Anyways, F35 is not stealth, it is not stealth in the IR and it is not stealth in low frequency radar.
It is also detectable by passive radar (via radio and TV station reflections, so also low frequency).
It is a bad fighter, has only one engine (so more easily shot down),
about everything you can think of in that thing is *wrong* including that fan for VTOL in some models.

Aircraft carriers are big billion-dollar targets. Vertical takeoff and
land lets small ships become carriers. Or any field or parking lot
become an airport.

Vertical landing is a nice feature, but vertical takeoff with full
bomb load and maximum fuel load is questionable. If it is possible, it
as least consumes a lot of fuel, reducing the combat radius.

At least during the Falkland war, the Harriers were launched
horizontally with a catapult and a ramp. After the mission with the
ammunition and fuel used, the light plane landed vertically.

While the ships were much smaller than US style carrier vehicles,
special ships with catapults were required, not just any ship would
do.

 

[Tom Gardner]

On 18/06/19 21:09, upsidedown@downunder.com wrote:

At least during the Falkland war, the Harriers were launched
horizontally with a catapult and a ramp. After the mission with the
ammunition and fuel used, the light plane landed vertically.

There was no catapault; the Harrier engines provided the oomph.

https://en.wikipedia.org/wiki/HMS_Illustrious_(R06)

 

[John Larkin]

On Tue, 18 Jun 2019 23:09:11 +0300, upsidedown@downunder.com wrote:

On Tue, 18 Jun 2019 10:09:06 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

Just like the F35.

The F35 will be OK. Fighter planes don't dogfight any more. F35 is an
electronics and missile platform.

We have those on order, there was one here last year,
and really, going by the sound I thought one flew over here yesterday.
There are 'air force days' somewhere not so far away, sort of where people can go
and look what's there, not in the airport close to here this year.
Anyways, F35 is not stealth, it is not stealth in the IR and it is not stealth in low frequency radar.
It is also detectable by passive radar (via radio and TV station reflections, so also low frequency).
It is a bad fighter, has only one engine (so more easily shot down),
about everything you can think of in that thing is *wrong* including that fan for VTOL in some models.

Aircraft carriers are big billion-dollar targets. Vertical takeoff and
land lets small ships become carriers. Or any field or parking lot
become an airport.

Vertical landing is a nice feature, but vertical takeoff with full
bomb load and maximum fuel load is questionable. If it is possible, it
as least consumes a lot of fuel, reducing the combat radius.

At least during the Falkland war, the Harriers were launched
horizontally with a catapult and a ramp. After the mission with the
ammunition and fuel used, the light plane landed vertically.

While the ships were much smaller than US style carrier vehicles,
special ships with catapults were required, not just any ship would
do.

The F35 is sometimes called STVL, slow takeoff and vertical land.


--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

 

[Tom Del Rosso]

Tom Gardner wrote:

Nobody in their right mind would sign-off a complex circuit
solely on the basis of a spice simulation. But Boeing is
planning on doing the equivalent for their 777X!

"Specifically, Boeing is "reducing the scope and duration
of certain costly physical tests used to certify the
planemaker's new aircraft," Reuters reported over the
weekend.
We're thus told that engineers working on Boeing's new
777X airliner project are intending to use computer
simulations instead of real-world flight tests to
validate their engineering decisions."

What could possibly go wrong with that?

https://www.theregister.co.uk/2019/06/17/boeing_certification_simulation_tests/

https://www.reuters.com/article/us-france-airshow-boeing-certification-e/exclusive-boeing-seeking-to-reduce-scope-duration-of-some-physical-tests-for-new-aircraft-sources-idUSKCN1TH0A3

Aircraft mechanics, who used to learn on mock-ups of engines and
systems, now learn on simulations. The Vaughn College of Aeronautics in
New York discarded all their mock-ups. There could be interesting
results.

 

[John S]

On 6/18/2019 9:04 AM, John Larkin wrote:

On Tue, 18 Jun 2019 04:19:24 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Mon, 17 Jun 2019 21:49:17 -0400) it happened bitrex
user@example.net> wrote in <yqXNE.41731$IQ6.21299@fx09.iad>:

The 737 Max handled very much like a 737 there were not huge engineering
surprises there. It was just different enough that they wanted to avoid
a different type rating. It was more of a bean-counting problem than an
engineering problem.

No, that plane is unstable by nature due to the position of the engines if I understand it right.
They wanted to fix that with some software.
That worked, then they 'simplified' the software, removed a G sensor, and that did not work.
The basic plane designs sucks.
A good plane flight strait without correction.

If you make a paper airplane, and it is bad, it will do strange things,
you could than add all sorts of systems to make it fly right
but it would still be a POS.

Just like the F35.

The F35 will be OK. Fighter planes don't dogfight any more. F35 is an
electronics and missile platform.

Yeah, that's what they thought in Viet Nam when they sent Phantoms to do
the job with electronics and missiles. Then they regretted it. Yes,
electronics and missiles are much more reliable today. But don't let
that fool you.

I suspect that manned fighter planes and bombers will be obsolete soon
anyhow.

You could be right. Missiles on a drone are a formidable combination.

 

[John Larkin]

On Wed, 19 Jun 2019 08:40:09 -0500, John S <Sophi.2@invalid.org>
wrote:

On 6/18/2019 9:04 AM, John Larkin wrote:
On Tue, 18 Jun 2019 04:19:24 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Mon, 17 Jun 2019 21:49:17 -0400) it happened bitrex
user@example.net> wrote in <yqXNE.41731$IQ6.21299@fx09.iad>:

The 737 Max handled very much like a 737 there were not huge engineering
surprises there. It was just different enough that they wanted to avoid
a different type rating. It was more of a bean-counting problem than an
engineering problem.

No, that plane is unstable by nature due to the position of the engines if I understand it right.
They wanted to fix that with some software.
That worked, then they 'simplified' the software, removed a G sensor, and that did not work.
The basic plane designs sucks.
A good plane flight strait without correction.

If you make a paper airplane, and it is bad, it will do strange things,
you could than add all sorts of systems to make it fly right
but it would still be a POS.

Just like the F35.

The F35 will be OK. Fighter planes don't dogfight any more. F35 is an
electronics and missile platform.

Yeah, that's what they thought in Viet Nam when they sent Phantoms to do
the job with electronics and missiles. Then they regretted it. Yes,
electronics and missiles are much more reliable today. But don't let
that fool you.

I suspect that manned fighter planes and bombers will be obsolete soon
anyhow.


You could be right. Missiles on a drone are a formidable combination.

Both the military and the airlines are having trouble recruiting
pilots.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Tom Gardner]

On 19/06/19 15:17, John Larkin wrote:

On Wed, 19 Jun 2019 08:40:09 -0500, John S <Sophi.2@invalid.org
wrote:

On 6/18/2019 9:04 AM, John Larkin wrote:
On Tue, 18 Jun 2019 04:19:24 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Mon, 17 Jun 2019 21:49:17 -0400) it happened bitrex
user@example.net> wrote in <yqXNE.41731$IQ6.21299@fx09.iad>:

The 737 Max handled very much like a 737 there were not huge engineering
surprises there. It was just different enough that they wanted to avoid
a different type rating. It was more of a bean-counting problem than an
engineering problem.

No, that plane is unstable by nature due to the position of the engines if I understand it right.
They wanted to fix that with some software.
That worked, then they 'simplified' the software, removed a G sensor, and that did not work.
The basic plane designs sucks.
A good plane flight strait without correction.

If you make a paper airplane, and it is bad, it will do strange things,
you could than add all sorts of systems to make it fly right
but it would still be a POS.

Just like the F35.

The F35 will be OK. Fighter planes don't dogfight any more. F35 is an
electronics and missile platform.

Yeah, that's what they thought in Viet Nam when they sent Phantoms to do
the job with electronics and missiles. Then they regretted it. Yes,
electronics and missiles are much more reliable today. But don't let
that fool you.

I suspect that manned fighter planes and bombers will be obsolete soon
anyhow.


You could be right. Missiles on a drone are a formidable combination.


Both the military and the airlines are having trouble recruiting
pilots.

Over here the military pilots are having difficult finding
aircraft to fly.

Over here we have more rear-admirals than capital ships
in the navy.

 

[John Larkin]

On Wed, 19 Jun 2019 04:03:47 -0400, "Tom Del Rosso"
<fizzbintuesday@that-google-mail-domain.com> wrote:

Tom Gardner wrote:
Nobody in their right mind would sign-off a complex circuit
solely on the basis of a spice simulation. But Boeing is
planning on doing the equivalent for their 777X!

"Specifically, Boeing is "reducing the scope and duration
of certain costly physical tests used to certify the
planemaker's new aircraft," Reuters reported over the
weekend.
We're thus told that engineers working on Boeing's new
777X airliner project are intending to use computer
simulations instead of real-world flight tests to
validate their engineering decisions."

What could possibly go wrong with that?

https://www.theregister.co.uk/2019/06/17/boeing_certification_simulation_tests/

https://www.reuters.com/article/us-france-airshow-boeing-certification-e/exclusive-boeing-seeking-to-reduce-scope-duration-of-some-physical-tests-for-new-aircraft-sources-idUSKCN1TH0A3

Aircraft mechanics, who used to learn on mock-ups of engines and
systems, now learn on simulations. The Vaughn College of Aeronautics in
New York discarded all their mock-ups. There could be interesting
results.

Pratt has a giant mechanics training facility in East Hartford, the
size of a modest stadium. They use real engines.


--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

 

[whit3rd]

On Monday, June 17, 2019 at 5:37:53 PM UTC-7, John Larkin wrote:

We're supposed to rework the economy of the entire world based on
climate simulations.

No, based on observations (simulations are the all-terms-considered
final step, NOT THE BASE). Several technologies, but NOT the
world (and not 'the economy') will have to change.

The claim you just made, wrenches ALL those nouns out of their proper meanings.

> What could possibly go wrong with that?

Do you have mind picture, or a simulation in mind? Why not? How else can you support an answer
to that question?

Imagination and simulations are ways of dealing with the future. If you
don't use them, you don't plan, and folk who DO will outcompete you.

 

[John Larkin]

On Thu, 20 Jun 2019 12:54:19 -0700 (PDT), whit3rd <whit3rd@gmail.com>
wrote:

On Monday, June 17, 2019 at 5:37:53 PM UTC-7, John Larkin wrote:

We're supposed to rework the economy of the entire world based on
climate simulations.

No, based on observations (simulations are the all-terms-considered
final step, NOT THE BASE). Several technologies, but NOT the
world (and not 'the economy') will have to change.

The claim you just made, wrenches ALL those nouns out of their proper meanings.

What could possibly go wrong with that?

Do you have mind picture, or a simulation in mind? Why not? How else can you support an answer
to that question?

Imagination and simulations are ways of dealing with the future. If you
don't use them, you don't plan, and folk who DO will outcompete you.

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want. Climate sims are obviously
tuned to hindcast accurately (they won't get published if they don't)
but that doesn't make them predictive. Past sims have not been very
predictive. The Statue of Liberty is still above water. The polar
bears are doing fine.

But, of course, we have more powerful computers now.





--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

 

On Thu, 20 Jun 2019 15:49:15 -0700, John Larkin
<jjlarkin@highland_snip_technology.com> wrote:

On Thu, 20 Jun 2019 12:54:19 -0700 (PDT), whit3rd <whit3rd@gmail.com
wrote:

On Monday, June 17, 2019 at 5:37:53 PM UTC-7, John Larkin wrote:

We're supposed to rework the economy of the entire world based on
climate simulations.

No, based on observations (simulations are the all-terms-considered
final step, NOT THE BASE). Several technologies, but NOT the
world (and not 'the economy') will have to change.

The claim you just made, wrenches ALL those nouns out of their proper meanings.

What could possibly go wrong with that?

Do you have mind picture, or a simulation in mind? Why not? How else can you support an answer
to that question?

Imagination and simulations are ways of dealing with the future. If you
don't use them, you don't plan, and folk who DO will outcompete you.

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want. Climate sims are obviously
tuned to hindcast accurately (they won't get published if they don't)
but that doesn't make them predictive.

I am not so sure about the hindcasts.

For example how does the simulation explain the Atlantic warm period
(Holocene climate optimum) in which some tree spices grow at the
Arctic Circle (based on tree trunks found in the bottom of lakes)
while currently the most northern areas are the southern Scandinavia.

Past sims have not been very
predictive. The Statue of Liberty is still above water. The polar
bears are doing fine.

But, of course, we have more powerful computers now.

 

[whit3rd]

On Thursday, June 20, 2019 at 3:51:40 PM UTC-7, John Larkin wrote:

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want.

That's now how one handles a simulation. Is that how you use SPICE?
I'm not trying to lie to myself when I fiddle with a model. Why would anyone?

It sounds like you're trying to sneak up on a conspiracy theory, but it would
have to be of the sort that starts with underpants and ends with
3. ???
4. PROFIT !!!

 

[Bill Sloman]

On Friday, June 21, 2019 at 6:29:38 AM UTC+2, upsid...@downunder.com wrote:

On Thu, 20 Jun 2019 15:49:15 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Thu, 20 Jun 2019 12:54:19 -0700 (PDT), whit3rd <whit3rd@gmail.com
wrote:

On Monday, June 17, 2019 at 5:37:53 PM UTC-7, John Larkin wrote:

We're supposed to rework the economy of the entire world based on
climate simulations.

No, based on observations (simulations are the all-terms-considered
final step, NOT THE BASE). Several technologies, but NOT the
world (and not 'the economy') will have to change.

The claim you just made, wrenches ALL those nouns out of their proper meanings.

What could possibly go wrong with that?

Do you have mind picture, or a simulation in mind? Why not? How else can you support an answer
to that question?

Imagination and simulations are ways of dealing with the future. If you
don't use them, you don't plan, and folk who DO will outcompete you.

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want. Climate sims are obviously
tuned to hindcast accurately (they won't get published if they don't)
but that doesn't make them predictive.

I am not so sure about the hindcasts.

For example how does the simulation explain the Atlantic warm period
(Holocene climate optimum) in which some tree species grow at the
Arctic Circle (based on tree trunks found in the bottom of lakes)
while currently the most northern areas are the southern Scandinavia.

For that they need information on deep ocean currents, which the Argo buoys are still collecting.

We know about the effect of the El Nino/La Nina alternation on local and global climate because they happen over a few year.

The Multidecadal Atlantic Oscillation

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

is a lot slower, and wasn't named until 1993.

It does seem to reflect ocean currents moving around. We can see the surface currents but the return currents flowing in the depths of the oceans are less easily observed (which is why the Argo Buoy observations were set under way).

https://en.wikipedia.org/wiki/Argo_(oceanography)

--
Bill Sloman, Sydney

 

[Bill Sloman]

On Friday, June 21, 2019 at 12:51:40 AM UTC+2, John Larkin wrote:

On Thu, 20 Jun 2019 12:54:19 -0700 (PDT), whit3rd <whit3rd@gmail.com
wrote:

On Monday, June 17, 2019 at 5:37:53 PM UTC-7, John Larkin wrote:

We're supposed to rework the economy of the entire world based on
climate simulations.

No, based on observations (simulations are the all-terms-considered
final step, NOT THE BASE). Several technologies, but NOT the
world (and not 'the economy') will have to change.

The claim you just made, wrenches ALL those nouns out of their proper meanings.

What could possibly go wrong with that?

Do you have mind picture, or a simulation in mind? Why not? How else can you support an answer
to that question?

Imagination and simulations are ways of dealing with the future. If you
don't use them, you don't plan, and folk who DO will outcompete you.

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want.

Not if you want the simulation to predict anything useful.

> Climate sims are obviously tuned to hindcast accurately (they won't get published if they don't) but that doesn't make them predictive. Past sims have not been very predictive.

Specific example? The first IPCC report came out in 1990, and what it said about what the world was gong to be like in 2019 wasn't too far off the mark.

The Statue of Liberty is still above water. The polar
> bears are doing fine.

And where are the published simulation results that suggested that they would be under water in 2019?

> But, of course, we have more powerful computers now.

Not that John Larkin has a clue what they would be telling him if he ever bothered to find out about what the science is saying.

He vastly prefers denialist propaganda web-sites which presumably provide him with all the flattery he craves, even though the "informaton" they present is deliberately misleading.

--
Bill Sloman, Sydney

 

On Fri, 21 Jun 2019 04:27:49 -0700 (PDT), Bill Sloman
<bill.sloman@ieee.org> wrote:

On Friday, June 21, 2019 at 6:29:38 AM UTC+2, upsid...@downunder.com wrote:
On Thu, 20 Jun 2019 15:49:15 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Thu, 20 Jun 2019 12:54:19 -0700 (PDT), whit3rd <whit3rd@gmail.com
wrote:

On Monday, June 17, 2019 at 5:37:53 PM UTC-7, John Larkin wrote:

We're supposed to rework the economy of the entire world based on
climate simulations.

No, based on observations (simulations are the all-terms-considered
final step, NOT THE BASE). Several technologies, but NOT the
world (and not 'the economy') will have to change.

The claim you just made, wrenches ALL those nouns out of their proper meanings.

What could possibly go wrong with that?

Do you have mind picture, or a simulation in mind? Why not? How else can you support an answer
to that question?

Imagination and simulations are ways of dealing with the future. If you
don't use them, you don't plan, and folk who DO will outcompete you.

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want. Climate sims are obviously
tuned to hindcast accurately (they won't get published if they don't)
but that doesn't make them predictive.

I am not so sure about the hindcasts.

For example how does the simulation explain the Atlantic warm period
(Holocene climate optimum) in which some tree species grow at the
Arctic Circle (based on tree trunks found in the bottom of lakes)
while currently the most northern areas are the southern Scandinavia.

For that they need information on deep ocean currents, which the Argo buoys are still collecting.

We know about the effect of the El Nino/La Nina alternation on local and global climate because they happen over a few year.

The Multidecadal Atlantic Oscillation

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

is a lot slower, and wasn't named until 1993.

That doesn't explain the warm period from 9000 to 5000 years ago
https://en.wikipedia.org/wiki/Holocene_climatic_optimum

It is interesting to note that in the beginning of this period, the
sea level rose by 60 m to current level apparently due to melting
glaciers. Since a lot of energy was lost to melting ice, the air would
have ben even warmer.

It does seem to reflect ocean currents moving around. We can see the surface currents but the return currents flowing in the depths of the oceans are less easily observed (which is why the Argo Buoy observations were set under way).

https://en.wikipedia.org/wiki/Argo_(oceanography)

 

[John Larkin]

On Fri, 21 Jun 2019 07:29:37 +0300, upsidedown@downunder.com wrote:

On Thu, 20 Jun 2019 15:49:15 -0700, John Larkin
jjlarkin@highland_snip_technology.com> wrote:

On Thu, 20 Jun 2019 12:54:19 -0700 (PDT), whit3rd <whit3rd@gmail.com
wrote:

On Monday, June 17, 2019 at 5:37:53 PM UTC-7, John Larkin wrote:

We're supposed to rework the economy of the entire world based on
climate simulations.

No, based on observations (simulations are the all-terms-considered
final step, NOT THE BASE). Several technologies, but NOT the
world (and not 'the economy') will have to change.

The claim you just made, wrenches ALL those nouns out of their proper meanings.

What could possibly go wrong with that?

Do you have mind picture, or a simulation in mind? Why not? How else can you support an answer
to that question?

Imagination and simulations are ways of dealing with the future. If you
don't use them, you don't plan, and folk who DO will outcompete you.

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want. Climate sims are obviously
tuned to hindcast accurately (they won't get published if they don't)
but that doesn't make them predictive.

I am not so sure about the hindcasts.

For example how does the simulation explain the Atlantic warm period
(Holocene climate optimum) in which some tree spices grow at the
Arctic Circle (based on tree trunks found in the bottom of lakes)
while currently the most northern areas are the southern Scandinavia.

The hindcasts usually curve-fit the (poorly) measured temp data since
the LIA. I don't know that anyone has good therories or models for the
giant swings over millions of years. Short-term sims are what's needed
to sell massive political intervention.

We'll all be dead in 12 years if we don't act NOW sort of thing.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[John Larkin]

On Thu, 20 Jun 2019 22:47:33 -0700 (PDT), whit3rd <whit3rd@gmail.com>
wrote:

On Thursday, June 20, 2019 at 3:51:40 PM UTC-7, John Larkin wrote:

In a complex, nonlinear, chaotic simulation, you can tune its
parameters to give any results you want.

That's now how one handles a simulation. Is that how you use SPICE?

I don't model nonlinear chaotic systems in Spice, I model electronic
circuits that I know I can simulate usefully. I do of course tune the
model to get the results that I can put into production; the trick
there is to not fool myself. Extreme sensitivity to any parameter or
value is one red flag that the circuit is not suitable for production.
Except when that sensitivity is in fact a mathematical artifact of
Spice, like the giant femtosecond spikes that someone here mentioned
recently.

Mike gets a lot of feedback about how LT Spice actually models
circuits. Climate modelers don't.

I'm not trying to lie to myself when I fiddle with a model. Why would anyone?

It sounds like you're trying to sneak up on a conspiracy theory, but it would
have to be of the sort that starts with underpants and ends with
3. ???
4. PROFIT !!!

Al Gore did pretty well.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics