On 2015\11\29 10:27, Scott wrote:
On Sun, 29 Nov 2015 10:13:26 +0000, Clive Page
wrote:

I'm surprised nobody else has noted here what I saw last week in (I
think) the Evening Standard: that TfL are about to tell passengers at
Holborn not to walk up the escalators. They claim that the
passenger-carrying capacity is greater when people stand on both left
and right. There was no mention of a penalty for those trying to walk
up the left hand side, but as we all know, it only takes one person to
block that side by standing on it for the whole system to degrade to
standing on both sides.

I really doubt the capacity arguments: it may be true that you get more
people on the standing side than on the walking side as walking needs a
bit more inter-person space, but on the other hand the number of people
per second is greater. I wonder if they have really done any measurements?

A much more productive move, in my opinion, would be to run their
escalators a bit faster: those in Moscow, Kiev, and other former soviet
cities, go about 50% faster in my experience. It comes as a slight
surprise to the visitor, but people seem to cope.

Or tell people not to stand on the escalators and keep walking :-)

If would help if they stopped telling us we must carry a dog.

In message , at 12:59:54 on
Sun, 29 Nov 2015, Recliner remarked:
On Sun, 29 Nov 2015 11:54:31 +0000, Roland Perry
wrote:

In message , at 11:23:17 on
Sun, 29 Nov 2015, remarked:

I really doubt the capacity arguments: it may be true that you get more
people on the standing side than on the walking side as walking needs a
bit more inter-person space, but on the other hand the number of people
per second is greater. I wonder if they have really done any
measurements?

It would be trivial to measu just stand at the top of one of the
escalators that has for the duration of the experiment people standing
on one side and walking up the other, and count how many people step off
the top on each side in a fixed period of time. A minute would be plenty
long enough.

Could the result vary with the demographic of the users and the time
and location.

Of course. I'm going to suggest that the time and location we
concentrate on is "Holborn in the rush hours".

Already done:
http://www.iimahd.ernet.in/assets/sn...f/2002-11-01Go
utamDutta.pdf

"For a double escalator with a rise greater than about 18.5 metres,
capacity would be greater if people could be encouraged to stand on both
sides."

From page 28:

Conclusion
It is therefore concluded that:

• Passengers will not stand on both sides of an escalator simply
because they are asked to.

• When passengers do stand on both sides capacity is high but this is
only because the majority of passengers do not treat the left hand
side as a standing side.

• However, except for short periods of time, passengers will not stand
on both sides unless they are persuaded (such as through an
advertising campaign) to treat both sides as standing sides.

• If passengers could be persuaded to treat both sides as standing
sides, capacity would not be so high and, if the assumptions made are
correct, it would only be advantageous for high rise double escalators
and for corner A double escalators.

• To impose such a selective policy would be even more difficult than
persuading passengers to stand on all escalators and the benefit
gained would be minimal.

--
Roland Perry

On 2015\11\29 13:17, Roland Perry wrote:
In message , at 12:59:54 on
Sun, 29 Nov 2015, Recliner remarked:

Already done:
http://www.iimahd.ernet.in/assets/sn...f/2002-11-01Go
utamDutta.pdf

"For a double escalator with a rise greater than about 18.5 metres,
capacity would be greater if people could be encouraged to stand on both
sides."

From page 28:

Conclusion
It is therefore concluded that:

• Passengers will not stand on both sides of an escalator simply
because they are asked to.

• When passengers do stand on both sides capacity is high but this is
only because the majority of passengers do not treat the left hand
side as a standing side.

• However, except for short periods of time, passengers will not stand
on both sides unless they are persuaded (such as through an
advertising campaign) to treat both sides as standing sides.

• If passengers could be persuaded to treat both sides as standing
sides, capacity would not be so high and, if the assumptions made are
correct, it would only be advantageous for high rise double escalators
and for corner A double escalators.

• To impose such a selective policy would be even more difficult than
persuading passengers to stand on all escalators and the benefit
gained would be minimal.



So if I get on an escalator and walk forward then I'm preventing the
people behind me from getting on, but if I stop dead immediately I'm
helping the progress of the people behind me. That seems incredible.

On Sun, 29 Nov 2015 13:37:01 +0000, Basil Jet
wrote:

On 2015\11\29 13:17, Roland Perry wrote:
In message , at 12:59:54 on
Sun, 29 Nov 2015, Recliner remarked:

Already done:
http://www.iimahd.ernet.in/assets/sn...f/2002-11-01Go
utamDutta.pdf

"For a double escalator with a rise greater than about 18.5 metres,
capacity would be greater if people could be encouraged to stand on both
sides."

From page 28:

Conclusion
It is therefore concluded that:

• Passengers will not stand on both sides of an escalator simply
because they are asked to.

• When passengers do stand on both sides capacity is high but this is
only because the majority of passengers do not treat the left hand
side as a standing side.

• However, except for short periods of time, passengers will not stand
on both sides unless they are persuaded (such as through an
advertising campaign) to treat both sides as standing sides.

• If passengers could be persuaded to treat both sides as standing
sides, capacity would not be so high and, if the assumptions made are
correct, it would only be advantageous for high rise double escalators
and for corner A double escalators.

• To impose such a selective policy would be even more difficult than
persuading passengers to stand on all escalators and the benefit
gained would be minimal.



So if I get on an escalator and walk forward then I'm preventing the
people behind me from getting on, but if I stop dead immediately I'm
helping the progress of the people behind me. That seems incredible.

How do you reach that conclusion???

On 2015\11\29 13:40, Recliner wrote:
On Sun, 29 Nov 2015 13:37:01 +0000, Basil Jet
wrote:

On 2015\11\29 13:17, Roland Perry wrote:
In message , at 12:59:54 on
Sun, 29 Nov 2015, Recliner remarked:

Already done:
http://www.iimahd.ernet.in/assets/sn...f/2002-11-01Go
utamDutta.pdf

"For a double escalator with a rise greater than about 18.5 metres,
capacity would be greater if people could be encouraged to stand on both
sides."

From page 28:

Conclusion
It is therefore concluded that:

• Passengers will not stand on both sides of an escalator simply
because they are asked to.

• When passengers do stand on both sides capacity is high but this is
only because the majority of passengers do not treat the left hand
side as a standing side.

• However, except for short periods of time, passengers will not stand
on both sides unless they are persuaded (such as through an
advertising campaign) to treat both sides as standing sides.

• If passengers could be persuaded to treat both sides as standing
sides, capacity would not be so high and, if the assumptions made are
correct, it would only be advantageous for high rise double escalators
and for corner A double escalators.

• To impose such a selective policy would be even more difficult than
persuading passengers to stand on all escalators and the benefit
gained would be minimal.



So if I get on an escalator and walk forward then I'm preventing the
people behind me from getting on, but if I stop dead immediately I'm
helping the progress of the people behind me. That seems incredible.

How do you reach that conclusion???

That's what people are implying when they say that the capacity of an
escalator is reduced by walking.

On Sun, 29 Nov 2015 13:00:51 +0100, Eric wrote:

On 2015-11-29, Clive Page wrote:
I'm surprised nobody else has noted here what I saw last week in (I
think) the Evening Standard: that TfL are about to tell passengers at
Holborn not to walk up the escalators.

They have done this on an ad-hoc basis in the past, I can remember it
being done at Victoria when it was very crowded.

They claim that the
passenger-carrying capacity is greater when people stand on both left
and right. There was no mention of a penalty for those trying to walk
up the left hand side, but as we all know, it only takes one person to
block that side by standing on it for the whole system to degrade to
standing on both sides.

Degrade? Not proven.

I really doubt the capacity arguments: it may be true that you get more
people on the standing side than on the walking side as walking needs a
bit more inter-person space, but on the other hand the number of people
per second is greater. I wonder if they have really done any measurements?

I would imagine they have, and they need to to be able to overcome the
inevitable objections to "stand on both sides".

I wouldn't object, I believe the capacity argument, and I always have.
When I first came to London 26 years ago, I was appalled at the convention
of standing on one side only. Think about it. Every time a step arrives
at the end of the escalator, 0 or 1 or 2 people get off. For maximum
capacity, it needs to be 2. On the right-hand side currently, there can
(with minor exceptions) be one person per step. On the left-hand side,
because, as you say, walking needs a bit more inter-person space, there
will never be one person for every step, so full capacity is never
being used.

But if people walk will they not spend less time on the escalator,
leaving more capacity for others? A 70mph road must be able to carry
more traffic each hour than a 30mph road.

There is another issue, which I think is equally important. Since
people are supposed to stand only on the right, all those who can't
or won't walk (especially up) end up queuing for the right hand side,
and the queue causes congestion. If they could queue for both sides,
the queue could also be two wide and therefore much shorter.

I can see your logic at peak periods but if passengers are permitted
to stand on both sides you could end up with those wanting to save a
bit of time (or build up their exercise steps) by walking during quiet
times unable to do so, as happens often in shops.

A much more productive move, in my opinion, would be to run their
escalators a bit faster: those in Moscow, Kiev, and other former soviet
cities, go about 50% faster in my experience. It comes as a slight
surprise to the visitor, but people seem to cope.

True.

Eric

In message , at 13:54:09 on Sun, 29 Nov
2015, Basil Jet remarked:

So if I get on an escalator and walk forward then I'm preventing the
people behind me from getting on, but if I stop dead immediately I'm
helping the progress of the people behind me. That seems incredible.

How do you reach that conclusion???

That's what people are implying when they say that the capacity of an
escalator is reduced by walking.

You are increasing the capacity of the escalator, but perhaps delaying
individual people who may have walked. As long as you ignore the effect
on the queues at the bottom of the escalator when doing those sums.
--
Roland Perry

In message , at 13:57:04 on
Sun, 29 Nov 2015, Scott remarked:

But if people walk will they not spend less time on the escalator,
leaving more capacity for others? A 70mph road must be able to carry
more traffic each hour than a 30mph road.

No, that's what variable speed limits are all about.
--
Roland Perry

Basil Jet wrote:
That's what people are implying when they say that the capacity of an
escalator is reduced by walking.

Well it all depends on (among other things) how many people walk, at
what speed, and when they arrive.

In any event given where we are starting from I'd put the proposition as
"the capacity of the escalators is reduced by the current practice of
leaving the left side empty for walkers". Whether or not that is true
depends both the number of people who walk up and on the speed at which
they do so. And also on the current incidence of people who block the
left side - eg from ignorance; by being morbidly obese; with luggage;
with large buggies; with young children.

IIRC it is a problem of a class which cannot be solved analytically but
can be modelled since computers have had sufficient grunt to process
large volumes of data.
--
Robin
reply to address is (meant to be) valid

On Sun, 29 Nov 2015 14:34:18 -0000, "Robin" wrote:

Basil Jet wrote:
That's what people are implying when they say that the capacity of an
escalator is reduced by walking.

Well it all depends on (among other things) how many people walk, at
what speed, and when they arrive.

In any event given where we are starting from I'd put the proposition as
"the capacity of the escalators is reduced by the current practice of
leaving the left side empty for walkers". Whether or not that is true
depends both the number of people who walk up and on the speed at which
they do so. And also on the current incidence of people who block the
left side - eg from ignorance; by being morbidly obese; with luggage;
with large buggies; with young children.

IIRC it is a problem of a class which cannot be solved analytically but
can be modelled since computers have had sufficient grunt to process
large volumes of data.

The issue seems to be simply that walkers leave a longer gap between
themselves than standers do. If people walk at different speeds, then
gaps open up, even if they were equally close at the beginning, and
the rest of the walkers behind the slow one also have to slow down.

Also, with longer lifts, fewer people feel like walking, so the
walking side gets under-used. That's why having both sides standing is
most likely to leave to a net increase in capacity with long upwards
escalators.