Systems 1.0 What They Should Have Told You in Class

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At school, college and university we learn about ‘academic systems’ - and they can be fully classifies, analyzed and characterized - they always have solutions. When we graduate into industry systems of this kind are deemed trivial and dispatched quickly and we then face a raft of problems previously skirted or avoided altogether. In this presentation we set out a core of things to be aware of right from the beginning of any study of systems - be they organic, inorganic, living tissue or a man made. Systems design, understanding and realization is not only important, it is vital to the progress and survival of our species, but severely limited by our bounded mathematical models, whilst being full of new and exciting challenges. Increasingly we are turning to our man made systems to help us unpick and unravel biology and the systems we have created and engineered. The Genome, Protein Stack, and communication between the two is one example and Artificial Intelligence is another. This slide set is not so much the first chapter, more likely the first sentence, in our overall understanding of systems, and one that is generally missing from courses in the topic. And our biggest challenge; we don’t know how big this book is going to be, or indeed how many chapters there will be and their precise content and coverage! This is what makes the study of ‘Systems’ so exciting - the opportunity to discover, understand and contribute!

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Systems 1.0

cochrane.org.uk

COCHRANE a s s o c i a t e s

ca-global.org

Peter Cochrane

Wednesday, 22 May 13

Definitions

What do we mean

by a system ?

Wednesday, 22 May 13

“A group of interacting, interrelated,

or interdependent elements forming

a complex whole”

Not entirely satisfactory...

Wednesday, 22 May 13

A functionally related group of elements, especially:

- The human body regarded as a functional physiological unit

- An organism as a whole, especially with regard to its vital processes or functions

- A group of physiologically or anatomically complementary organs or parts

- A group of interacting mechanical or electrical components

- A network of structures and channels, as for communication, travel, or distribution

- A network of related computer software, hardware, and data transmission devices

An organized set of interrelated ideas or principles

- A social, economic, or political organisational form

- A naturally occurring group of objects or phenomena: the solar system.

- A set of objects or phenomena grouped together for classification or analysis

- A condition of harmonious, orderly interaction

- An organized and coordinated method; a procedure

Perhaps a bit more comprehensive...

Wednesday, 22 May 13

But what a lot of words,

disjointed concepts and

examples to remember...

...might we do better ?

Wednesday, 22 May 13

‘A system takes energy, matter,

information, and transforms its

nature’

Wednesday, 22 May 13

Ergo; Systems are ‘essentially entropic’

S = k log W

Wednesday, 22 May 13

Note that we do not fully understand...Energy and Matter

Time and Space

...they may all just shr ink down to space...

...they may just shrink down to space...

...but until we get a GUT this will remain uncertain...

Wednesday, 22 May 13

AXIOM...still not understood by many...

Taking an interest in every system known to mankind pays dividends in providing us with ins ights and cha l leng ing concepts and occasionally , really useful results...

..and we no longer design, deploy and operate our systems in isolation...we live in a world of natural and unnatural systems... evolved and designed...

...and the way they connect coexist and intereact is important especially when life dependency and mission critical issues are at stake !

Wednesday, 22 May 13

Some big differences between

Man and Mother Nature...

Only we designOnly we optimize We often appear use

vastly complex solutions to achieve incredibly simple outcomes...

Wednesday, 22 May 13

Whilst Mother Nature...

Only evolves systemsOnly goes for ‘good enough’ and optimizes nothing

She conceals her underlying complexity at every level of her constructs and activity...

Wednesday, 22 May 13

“Perfection is the enemy of

Good Enough”

Defining ‘good enough’ is not always trivial and is generally the biggest challenge !

Wednesday, 22 May 13

Some broad brush system generalitiesAnalogue dominant

Digital spreading fast

Hybrid Analogue//Digital ubiquitous

What we know advancing rapidly

Our understanding mathematically limited

Made by mankind we all die without them

Made by machine we all die without them

Our species survival depends upon good systems

Our planets survival depends upon good systems

Machine intelligence overtaking us in many areas

Symbiosis necessary man machine partnerships

Challenges formidable but interesting

Wednesday, 22 May 13

What’s in THE ENVIRONMENT?

s(t) h(t) o(t)

Other systems of the same or differing type may be sharing the same space or some part of it, and therefore there can be many obvious and hidden opportunities for aliasing....

AirWaterEarthMachinesLifeforms

FluidsSolidsChemicalsRadiationInformation

Wednesday, 22 May 13

What’s in THE BOX ?

s(t) h(t) o(t)

ChemicalPhysicalInformation/Data ProcessingMathematicalNaturalUnnatural

BiologicalElectricalElectronicMechanicalComputational+++

Optical AcousticOrganicInorganicLife forms+++

Wednesday, 22 May 13

What does the output do?

s(t) h(t) o(t)

In the general case it impacts/changes the environment and the input and is often a grossly non-linear series of loops

e(t)

f(t)

Wednesday, 22 May 13

What’s in THE BOX ?

s(t) h(t) o(t)

What can we describe and define

Optical Acoustic++++++Life forms

o(t) = h[s(t)] = h(s) for ease of notation

o = a + bt + ct2 + dt3 et4 + ft5 is the largest polynomial we can solve for very limited and narrow range of cases

In the absence of a closed form solution we often reduced to using polynomial or some other form of approximate descriptor

Wednesday, 22 May 13

But many of our systems are of a much higher order with hundreds of feedback and feedforward loops...

Wednesday, 22 May 13

They also have hundreds of diverse inputs and outputs and cannot be fully flood, or combinatorially tested...

Wednesday, 22 May 13

SizeScaleComplexityConnectivitySophisticationConnectivity

MTBFSpeedAgility

ReliabilityTestability

PredicabilityResponsivity

Common/General system traits

Wednesday, 22 May 13

SizeScaleComplexityConnectivitySophisticationConnectivity

MTBFSpeedAgility

ReliabilityTestability

PredicabilityResponsivity

Common/General system traits

Wednesday, 22 May 13

SizeScaleComplexityConnectivitySophisticationConnectivity

MTBFSpeedAgility

ReliabilityTestability

PredicabilityResponsivity

Common/General system traits

Wednesday, 22 May 13

SizeScaleComplexityConnectivitySophisticationConnectivity

MTBFSpeedAgility

ReliabilityTestability

PredicabilityResponsivity

Often difficult to define with any great precision

Common/General system traits

Wednesday, 22 May 13

SizeScaleComplexityConnectivitySophisticationConnectivity

MTBFSpeedAgility

ReliabilityTestability

PredicabilityResponsivity

Cost MTTR LatencyPower Heat Resources

Often difficult to define with any great precision

Common/General system traits

Wednesday, 22 May 13

Common/General system traits

s(t) h(t) o(t)

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

Wednesday, 22 May 13

Common/General system traits

s(t) h(t) o(t)

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

SimpleSingularLinear

ComplexMulti - I/OLinearNon-Linear

Wednesday, 22 May 13

All known, understood, well described and characterized, bounded, and well behaved with causality preserved

Contained/bounded in/by some known, or well defined, environment/conditions

Simple System - Key Features 1

s(t) h(t) o(t)

s(t) = Stimulus h(t) = Operator o(t) = Output }

s(t) and o(t) originate and terminate within the environment

Wednesday, 22 May 13

All known, understood, well described

and characterized, bounded, and well

behaved with causality preserved

Contained/bounded in/by some known, or well defined, environment/conditions

Complex System - Key Features I

s(t) = Stimulus h(t) = Operator o(t) = Output }

s(t) and o(t) originate and terminate within the environment

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

Wednesday, 22 May 13

All known, understood, well described

and characterized, bounded, and well

behaved with causality preserved

Contained/bounded in/by some known, or well defined, environment/conditions

Complex System - Key Features I

s(t) = Stimulus h(t) = Operator o(t) = Output }

s(t) and o(t) originate and terminate within the environment

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

X

Wednesday, 22 May 13

All known, understood, well described

and characterized, bounded, and well

behaved with causality preserved

Contained/bounded in/by some known, or well defined, environment/conditions

Complex System - Key Features I

s(t) = Stimulus h(t) = Operator o(t) = Output }

s(t) and o(t) originate and terminate within the environment

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

X XMay be violated by design or implementation error ++

Wednesday, 22 May 13

All known, understood, well described

and characterized, bounded, and well

behaved with causality preserved

Contained/bounded in/by some known, or well defined, environment/conditions

Complex System - Key Features I

s(t) = Stimulus h(t) = Operator o(t) = Output }

s(t) and o(t) originate and terminate within the environment

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

X Any one or more or all of these

conditions may no longer true

X XMay be violated by design or implementation error ++

Wednesday, 22 May 13

Response matches needSymbiotic with the environmentPredictable, reliable, with a fast recovery timeUpgrades and changes not traumatic or riskyShocks are not terminal or unduly debilitatingReproducible, easy to deploy and maintain/repair/replace

Simple System - Key Features II

s(t) h(t) o(t)

Wednesday, 22 May 13

Response matches needSymbiotic with the environmentPredictable, reliable, with a fast recovery timeUpgrades and changes not traumatic or riskyShocks are not terminal or unduly debilitatingReproducible, easy to deploy and maintain/repair/replace

Simple System - Key Features II

s(t) h(t) o(t)

Sometimes we cannot satisfy this wish list 100%

Wednesday, 22 May 13

Complex System - Key Features II

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

Response matches needSymbiotic with the environmentPredictable, reliable, with a fast recovery timeUpgrades and changes not traumatic or riskyShocks are not terminal or unduly debilitatingReproducible, easy to deploy and maintain/repair/replace

Wednesday, 22 May 13

Complex System - Key Features II

s1(t)s2(t)s3(t)

si(t)

o1(t)

ok(t)

o3(t)o2(t)

hi(t)

Response matches needSymbiotic with the environmentPredictable, reliable, with a fast recovery timeUpgrades and changes not traumatic or riskyShocks are not terminal or unduly debilitatingReproducible, easy to deploy and maintain/repair/replace

Almost by definition we cannot satisfy this wish list 100%

Wednesday, 22 May 13

The nature of non-linearity

Linear = Output scales with input in some way: y = ax + b

Non - Linear = Output does not scale with input: e.g. y = a.exPredictable

Non - Linear = I/O does not scale with: e.g. y = f1(x0)+ fs(x1) Seldom or never gives a repeatable output for all input states

Un Predictable

Wednesday, 22 May 13

The nature of non-linearity

Linear = Output scales with input in some way: y = ax + b

Non - Linear = Output does not scale with input: e.g. y = a.exPredictable

Non - Linear = I/O does not scale with: e.g. y = f1(x0)+ fs(x1) Seldom or never gives a repeatable output for all input states

Un Predictable

Huh !!!

Wednesday, 22 May 13

How come ???

Non - Linear = I/O does not scale with: e.g. y = f1(x0)+ fs(x1) Seldom or never gives a repeatable output for all input states

Un Predictable

Memory Dynamic/Stochastic non-linearities Input/Output uncertainties Feedback VariabilityDelay Dynamic/Stochastic configurations Conditional uncertainties Feedforward Variability

Dynamic non-linearitiesDynamic configurations

Wednesday, 22 May 13

Examples

Non - Linear = I/O does not scale with: e.g. y = f1(x0)+ fs(x1) Seldom or never gives a repeatable output for all input states

Un Predictable

Weather Markets War People

Wednesday, 22 May 13

Examples

Non - Linear = I/O does not scale with: e.g. y = f1(x0)+ fs(x1) Seldom or never gives a repeatable output for all input states

Un Predictable

Network Traffic

Large BioEntities

ChanceGambling

AtomicInteractions

Wednesday, 22 May 13

AXIOMS - For Networked // Aliased Systems

Complex Systems are never rendered simpler - without incurring errors/costs !

Simple systems are mostly rendered complex - unless we are very lucky !

Complex systems never get easier to characterise

Simple systems always get more difficult to characterise

Simple systems don’t make the complex simpler

Complex systems always make the simple more complex

Wednesday, 22 May 13

AXIOMS - For Networked // Aliased Systems

Complex Systems are never stronger than their weakest element

Systems are never simpler than their most complex elements

There are lots of simple solutions to complex problems... ....but they are always wrong !

Wednesday, 22 May 13

Should you discover sometime in the future, that any of this is untrue, or does not hold...

....then there is a Nobel Prize waiting for you !!!

Wednesday, 22 May 13

How can we be so sure ?

Because the universe is governed by Entropy

‘Gods Celestial Ratchet’

Or

Wednesday, 22 May 13

Huh ?

That’s a story for another day

AND

Systems 1.1

Wednesday, 22 May 13

AND NOW

This Weeks Assignment!

Wednesday, 22 May 13

Read everything you can on Entropy and come back....

...prepared to discuss and debate

Wednesday, 22 May 13

the

journey

has

Begun

Wednesday, 22 May 13

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