Feed-Forward Neural Networks - Mathematical Models Based on … · Analysis,ModellingandSolutions...

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c© Die Zeit, 14.6.2007

Feed-Forward Neural NetworksMathematical Models Based on Neural Networks

Dieter Kilsch

eh. Technische Hochschule Bingen, FB 2 • Technik, Informatik und WirtschaftGSE und APL-Germany

Böblingen

November 28th, 2016

Feed-Forward Neural NetworksMathematical Models Based on Neural Networks

Dieter Kilsch

eh. Technische Hochschule Bingen, FB 2 • Technik, Informatik und WirtschaftGSE und APL-Germany

Böblingen

November 28th, 2016

My first „date“ with APL: 1984

My first APL-conference: St. Petersburg 1992

Analysis, Modelling and Solutions My Vision of Mobility

1 Analysis, Modelling and Solutions

2 Neurons and Neural Networks

3 Accident Severity

4 Comfort in Cabriolet: Active Torsion Damping

5 Further Examples and Conclusion

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 4 / 48

Analysis, Modelling and Solutions My Vision of Mobility

1 Analysis, Modelling and SolutionsMy Vision of MobilityObjectives

2 Neurons and Neural Networks

3 Accident Severity

4 Comfort in Cabriolet: Active Torsion Damping

5 Further Examples and Conclusion

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 5 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Convenience by Autonomous Vehicles

2007: Vision

c© Die Zeit, 14.6.2007

The car manages itself,

the driver’s mind

is free to enjoy live.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 6 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Convenience by Autonomous Vehicles

2007: Vision

c© Die Zeit, 14.6.2007

The car manages itself,

the driver’s mind

is free to enjoy live.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 6 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Convenience by Autonomous Vehicles

heute: ? Vision ?

c© Die Zeit, 14.6.2007

The car manages itself,

the driver’s mind

is free to enjoy live.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 6 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Vision: Requirements

Vision

c© ADAC, Juli 2006

The car senses

and controls.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 7 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Autonomous Cars Come True

“First Autonomes Car on Public Roads”

TU Braunschweig, https://www.tu-braunschweig.de/presse/medien/presseinformationen?year=2010&pinr=133

The car drives, the driver enjoys . . .

Leonie 8.10.2010Weltweit erstes automatisches Fahrenim realen StadtverkehrForschungsfahrzeug „Leonie“ fährt au-tomatisch auf dem BraunschweigerStadtringWeltpremiere in Braunschweig: Erstmalsfährt heute ein Fahrzeug automatisch imalltäglichen Stadtverkehr. Im Rahmendes Forschungsprojekts „Stadtpilot“hat die Technische Universität Braun-schweig in ihrem Kompetenzzentrum,dem Niedersächsischen Forschungszen-trum Fahrzeugtechnik, ein Forschungs-fahrzeug entwickelt, dass automatischeine vorgegebene Strecke im regulärenVerkehr fährt.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 8 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Autonomous Cars Come True

Self-Driving Car Test: Steve Mahan(youtube)

Autopiloten 4.10.2012Das Wort Geisterfahrer bekommt inKalifornien gerade eine ganz neue Be-deutung: Seit vergangener Wochedürfen auf den Highways selbsts-teuernde Autos cruisen. Wunderndarf sich der Kalifornier also nicht,wenn er demnächst ein Auto ohneFahrer neben sich hat. Denn dersitzt vermutlich auf der Rückbank undguckt Fernsehen, während der Autopi-lot lenkt.Das neue System stammt von Google,dem es nun nicht mehr reicht, Straßennur abzufilmen. 300 000 Meilenhätten die Gefährte schon unfallfreizurückgelegt, teilte der Internetkonz-ern mit.

CHRISTINA KYRIASOGLOU c© Die Zeit

Das Auto lenkt, der Mensch denkt, . . .Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 9 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Autonomous Cars Come True

Freightliner Inspiration Truck Unveiled at Hoover Dam LAS VEGAS, 5-5-2015, DTNA

First Licensed Autonomous Commercial Truck to Drive on U.S. Public HighwayIn a spectacular evening ceremony at Hoover Dam, Daimler Trucks North America(DTNA) unveiled the Freightliner Inspiration Truck to several hundred international newsmedia, trucking industry analysts and officials.

Daimler Inspiration Truck - So fährt derRobo-Truck von Mercedes (youtube)

The Freightliner Inspiration Truck isthe first licensed autonomous commercialtruck to operate on an open public high-way in the United States. Developed byengineers at DTNA, it promises to unlockautonomous vehicle advancements that re-duce accidents, improve fuel consumption,cut highway congestion, and safeguard theenvironment.

http://www.freightlinerinspiration.com/http://www.freightlinerinspiration.com/newsroom/press/inspiration- truck-unveiled/https://www.youtube.com/watch?v=mRkOGU3Gz9Yhttps://www.youtube.com/watch?v=LL4dbq-n8Pghttps://www.youtube.com/watch?v=LJz4Ms_5AXE

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 10 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Autonomous Cars Come True

Freightliner Inspiration Truck Unveiled at Hoover Dam LAS VEGAS, 5-5-2015, DTNA

First Licensed Autonomous Commercial Truck to Drive on U.S. Public HighwayIn a spectacular evening ceremony at Hoover Dam, Daimler Trucks North America(DTNA) unveiled the Freightliner Inspiration Truck to several hundred international newsmedia, trucking industry analysts and officials.

Daimler Inspiration Truck - So fährt derRobo-Truck von Mercedes (youtube)

The Freightliner Inspiration Truck isthe first licensed autonomous commercialtruck to operate on an open public high-way in the United States. Developed byengineers at DTNA, it promises to unlockautonomous vehicle advancements that re-duce accidents, improve fuel consumption,cut highway congestion, and safeguard theenvironment.

http://www.freightlinerinspiration.com/http://www.freightlinerinspiration.com/newsroom/press/inspiration- truck-unveiled/https://www.youtube.com/watch?v=mRkOGU3Gz9Yhttps://www.youtube.com/watch?v=LL4dbq-n8Pghttps://www.youtube.com/watch?v=LJz4Ms_5AXE

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 10 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Autonomous Cars Come True

Freightliner Inspiration Truck Unveiled at Hoover Dam LAS VEGAS, 5-5-2015, DTNA

First Licensed Autonomous Commercial Truck to Drive on U.S. Public HighwayIn a spectacular evening ceremony at Hoover Dam, Daimler Trucks North America(DTNA) unveiled the Freightliner Inspiration Truck to several hundred international newsmedia, trucking industry analysts and officials.

Daimler Inspiration Truck - So fährt derRobo-Truck von Mercedes (youtube)

The Freightliner Inspiration Truck isthe first licensed autonomous commercialtruck to operate on an open public high-way in the United States. Developed byengineers at DTNA, it promises to unlockautonomous vehicle advancements that re-duce accidents, improve fuel consumption,cut highway congestion, and safeguard theenvironment.

http://www.freightlinerinspiration.com/http://www.freightlinerinspiration.com/newsroom/press/inspiration- truck-unveiled/https://www.youtube.com/watch?v=mRkOGU3Gz9Yhttps://www.youtube.com/watch?v=LL4dbq-n8Pghttps://www.youtube.com/watch?v=LJz4Ms_5AXE

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 10 / 48

Analysis, Modelling and Solutions My Vision of Mobility

Autonomous Cars Come True

Freightliner Inspiration Truck Unveiled at Hoover Dam LAS VEGAS, 5-5-2015, DTNA

First Licensed Autonomous Commercial Truck to Drive on U.S. Public HighwayIn a spectacular evening ceremony at Hoover Dam, Daimler Trucks North America(DTNA) unveiled the Freightliner Inspiration Truck to several hundred international newsmedia, trucking industry analysts and officials.

Daimler Inspiration Truck - So fährt derRobo-Truck von Mercedes (youtube)

The Freightliner Inspiration Truck isthe first licensed autonomous commercialtruck to operate on an open public high-way in the United States. Developed byengineers at DTNA, it promises to unlockautonomous vehicle advancements that re-duce accidents, improve fuel consumption,cut highway congestion, and safeguard theenvironment.

http://www.freightlinerinspiration.com/http://www.freightlinerinspiration.com/newsroom/press/inspiration- truck-unveiled/https://www.youtube.com/watch?v=mRkOGU3Gz9Yhttps://www.youtube.com/watch?v=LL4dbq-n8Pghttps://www.youtube.com/watch?v=LJz4Ms_5AXE

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 10 / 48

Analysis, Modelling and Solutions Objectives

How to Solve a Problem?

Algorithm

Intuitively build amodelDeduce a numeri-cal algorithm

Put it into a pro-gramUse it respectingthe preconditions

Expert System

Intuitively build anmodelFormulate rules

Apply Rules

may solve relatedproblems

Neural Network

Intuitively build anmodelneeds samplingpointsgeneralizes based onsampling data

applies to relatedproblems

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 11 / 48

Analysis, Modelling and Solutions Objectives

How to Solve a Problem?

Algorithm

Intuitively build amodelDeduce a numeri-cal algorithm

Put it into a pro-gramUse it respectingthe preconditions

Expert System

Intuitively build anmodelFormulate rules

Apply Rules

may solve relatedproblems

Neural Network

Intuitively build anmodelneeds samplingpointsgeneralizes based onsampling data

applies to relatedproblems

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 11 / 48

Analysis, Modelling and Solutions Objectives

How to Solve a Problem?

Algorithm

Intuitively build amodelDeduce a numeri-cal algorithm

Put it into a pro-gramUse it respectingthe preconditions

Expert System

Intuitively build anmodelFormulate rules

Apply Rules

may solve relatedproblems

Neural NetworkIntuitively build anmodelneeds samplingpointsgeneralizes based onsampling data

applies to relatedproblems

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 11 / 48

Analysis, Modelling and Solutions Objectives

Physical Performance: An Engine on a Test Bench

load, throttle walve, ignition an-gle, dwell angle, mixture, voltage,temperature of engine, air and oil

→rotational speed, con-sumption, temperatureand amount of emission

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 12 / 48

Analysis, Modelling and Solutions Objectives

Physical Performance: An Engine on a Test Bench

TargetsCreate the optimal engine characteristic map.. . . also regarding start situation.Reduce test bench time.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 12 / 48

Analysis, Modelling and Solutions Objectives

Mathematical Model of an Engine

f

Mathematical model: abstractionLook at the engine as a functionAssumes functional dependencies (one-one)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 13 / 48

Analysis, Modelling and Solutions Objectives

Mathematical Model of an Engine

KNN

Models with artificial neural networkArtificial neural networks should learn to “behave” like an engine.The knowledge must come from (measured) data.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 14 / 48

Analysis, Modelling and Solutions Objectives

Application: Reduce Test Bench Time

Optimization of characteristic maps using artificial neural networks

KNN

e o e o

f f

Fill the neural networks with the “knowledge” of several engines:measured data from test benchNew engine: extending the knowledge base with a few data from testbenchOptimize the characteristic map using the trained neural network

R. Stricker, BMW AG, 1996

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 15 / 48

Analysis, Modelling and Solutions Objectives

Curve Fitting (Least Square Method, Regression)

“Learning” only in the last layer

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 16 / 48

Analysis, Modelling and Solutions Objectives

Curve Fitting (Least Sq. M., Regression): Examples

Polynomial Fitting

f (x) =n∑

k=0akxk

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 17 / 48

Analysis, Modelling and Solutions Objectives

Curve Fitting (Least Sq. M., Regression): Examples

Polynomial Fitting

f (x) =n∑

k=0akxk

Fourier Fitting

f (x) = a0 +n∑

k=1ak cos(ωkx) + ak sin(ωkx)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 17 / 48

Analysis, Modelling and Solutions Objectives

Curve Fitting (Least Sq. M., Regression): Examples

Polynomial Fitting

Fourier Fitting

Stress-Strain-Diagram BMW 1996

f (x) = a−1x + .1 + a0 + a1x + a2x2 + a3x3

− provides:a−1 = 2.2677;a0 = 297.9072;a1 = 71.4932;a2 = −33.7959;a3 = 5.5016.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 17 / 48

Neurons and Neural Networks NeuroScience

1 Analysis, Modelling and Solutions

2 Neurons and Neural NetworksNeuroScienceArtificial Neuron, Linear SeperationNeural Network Learning

3 Accident Severity

4 Comfort in Cabriolet: Active Torsion Damping

5 Further Examples and Conclusion

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 18 / 48

Neurons and Neural Networks NeuroScience

Brain — Computer: a Comparison

Brain and standard computershighly perform w.r.t. to different tasks:

BrainHighly parallelFault tolerantPattern recognitionGeneralizationSelf-organizingca. 1011 neurons, reducingto 107

Every neuron has ca. 104connected neurons.

Computer

PreciseFaultless storingFast algorithmic calculations

von Neumann architecture

Nearly stand alone

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 19 / 48

Neurons and Neural Networks NeuroScience

Brain — Computer: a Comparison

Brain and standard computershighly perform w.r.t. to different tasks:

BrainHighly parallelFault tolerantPattern recognitionGeneralizationSelf-organizingca. 1011 neurons, reducingto 107

Every neuron has ca. 104connected neurons.

Computer

PreciseFaultless storingFast algorithmic calculations

von Neumann architecture

Nearly stand alone

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 19 / 48

Neurons and Neural Networks NeuroScience

Brain — Computer: a Comparison

Brain and standard computershighly perform w.r.t. to different tasks:

BrainHighly parallelFault tolerantPattern recognitionGeneralizationSelf-organizingca. 1011 neurons, reducingto 107

Every neuron has ca. 104connected neurons.

Computer

PreciseFaultless storingFast algorithmic calculations

von Neumann architecture

Nearly stand alone

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 19 / 48

Neurons and Neural Networks NeuroScience

The Biological Neuron

Principles of Operation 1 Impulse through the axon.2 Synapses collect impulse.(Chemical reaction)

3 Dendrites transmit it.4 Nucleus gets impulse.5 Overall impulse:Excitation of the neuron.

6 Threshold target reached:

Learning:Synapses, dendrites enhance their connection.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 20 / 48

Neurons and Neural Networks NeuroScience

The Biological Neuron

Principles of Operation 1 Impulse through the axon.2 Synapses collect impulse.(Chemical reaction)

3 Dendrites transmit it.4 Nucleus gets impulse.5 Overall impulse:Excitation of the neuron.

6 Threshold target reached:

Learning:Synapses, dendrites enhance their connection.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 20 / 48

Neurons and Neural Networks NeuroScience

The Biological Neuron

Principles of Operation 1 Impulse through the axon.2 Synapses collect impulse.(Chemical reaction)

3 Dendrites transmit it.4 Nucleus gets impulse.5 Overall impulse:Excitation of the neuron.

6 Threshold target reached:

Learning:Synapses, dendrites enhance their connection.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 20 / 48

Neurons and Neural Networks NeuroScience

The Biological Neuron

Principles of Operation 1 Impulse through the axon.2 Synapses collect impulse.3 Dendrites transmit it.4 Nucleus gets impulse.(Electrical impulse)

5 Overall impulse:Excitation of the neuron.

6 Threshold target reached:

Learning:Synapses, dendrites enhance their connection.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 20 / 48

Neurons and Neural Networks NeuroScience

The Biological Neuron

Principles of Operation 1 Impulse through the axon.2 Synapses collect impulse.3 Dendrites transmit it.4 Nucleus gets impulse.(Electrical impulse)

5 Overall impulse:Excitation of the neuron.

6 Threshold target reached:

Learning:Synapses, dendrites enhance their connection.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 20 / 48

Neurons and Neural Networks NeuroScience

The Biological Neuron

Principles of Operation 1 Impulse through the axon.2 Synapses collect impulse.3 Dendrites transmit it.4 Nucleus gets impulse.5 Overall impulse:Excitation of the neuron.

6 Threshold target reached:neuron sends impulse.

Learning:Synapses, dendrites enhance their connection.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 20 / 48

Neurons and Neural Networks NeuroScience

The Biological Neuron

Principles of Operation 1 Impulse through the axon.2 Synapses collect impulse.3 Dendrites transmit it.4 Nucleus gets impulse.5 Overall impulse:Excitation of the neuron.

6 Threshold target reached:neuron sends impulse.

Learning:Synapses, dendrites enhance their connection.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 20 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

The Artificial Neuron

1 input (vector) ~e = (e1, . . . , en), −1 to be used by threshold2 weights and threshold ~w = (w1, . . . , wn) and θ3 net (value), propagation net = 〈~e, ~w 〉 − θ =

∑ni=1 eiwi − θ

4 activation (primitive function), activity a = a(〈~e, ~w 〉 − θ)5 output function6 otuput o = o(a(〈~w , ~e 〉 − θ))

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 21 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

The Artificial Neuron

1 input (vector) ~e = (e1, . . . , en), −1 to be used by threshold2 weights and threshold ~w = (w1, . . . , wn) and θ3 net (value), propagation net = 〈~e, ~w 〉 − θ =

∑ni=1 eiwi − θ

4 activation (primitive function), activity a = a(〈~e, ~w 〉 − θ)5 output function6 otuput o = o(a(〈~w , ~e 〉 − θ))

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 21 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

The Artificial Neuron

1 input (vector) ~e = (e1, . . . , en), −1 to be used by threshold2 weights and threshold ~w = (w1, . . . , wn) and θ3 net (value), propagation net = 〈~e, ~w 〉 − θ =

∑ni=1 eiwi − θ

4 activation (primitive function), activity a = a(〈~e, ~w 〉 − θ)5 output function6 otuput o = o(a(〈~w , ~e 〉 − θ))

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 21 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

The Artificial Neuron

1 input (vector) ~e = (e1, . . . , en), −1 to be used by threshold2 weights and threshold ~w = (w1, . . . , wn) and θ3 net (value), propagation net = 〈~e, ~w 〉 − θ =

∑ni=1 eiwi − θ

4 activation (primitive function), activity a = a(〈~e, ~w 〉 − θ)5 output function6 otuput o = o(a(〈~w , ~e 〉 − θ))

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 21 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

The Artificial Neuron

1 input (vector) ~e = (e1, . . . , en), −1 to be used by threshold2 weights and threshold ~w = (w1, . . . , wn) and θ3 net (value), propagation net = 〈~e, ~w 〉 − θ =

∑ni=1 eiwi − θ

4 activation (primitive function), activity a = a(〈~e, ~w 〉 − θ)5 output function6 otuput o = o(a(〈~w , ~e 〉 − θ))

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 21 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Sigmoidal Activation

a(x) = tanh(gx) : R→(−1, 1)

Derivative: a′(x) = g(− tanh(gx)2) = g(1− a(x)2) ; a′(0) = g

Alternative Activations:1 a(x) = 1

1+e−gx : R→(0, 1), a′(x) = g(1− a(x)) · a(x) ; a′(0) = g4

2 Piecewise parabola, easy implementation in hard ware (Carmen Stumm)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 22 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Sigmoidal Activation

a(x) = tanh(gx) : R→(−1, 1)

Derivative: a′(x) = g(− tanh(gx)2) = g(1− a(x)2) ; a′(0) = g

Alternative Activations:1 a(x) = 1

1+e−gx : R→(0, 1), a′(x) = g(1− a(x)) · a(x) ; a′(0) = g4

2 Piecewise parabola, easy implementation in hard ware (Carmen Stumm)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 22 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Sigmoidal Activation

a(x) = tanh(gx) : R→(−1, 1)

Derivative: a′(x) = g(− tanh(gx)2) = g(1− a(x)2) ; a′(0) = g

Alternative Activations:1 a(x) = 1

1+e−gx : R→(0, 1), a′(x) = g(1− a(x)) · a(x) ; a′(0) = g4

2 Piecewise parabola, easy implementation in hard ware (Carmen Stumm)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 22 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Sigmoidal Activation

a(x) = tanh(gx) : R→(−1, 1)

Derivative: a′(x) = g(− tanh(gx)2) = g(1− a(x)2) ; a′(0) = g

Alternative Activations:1 a(x) = 1

1+e−gx : R→(0, 1), a′(x) = g(1− a(x)) · a(x) ; a′(0) = g4

2 Piecewise parabola, easy implementation in hard ware (Carmen Stumm)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 22 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Bipolar and Binary Threshold Function

a(x) = sign(x) : R→[−1, 1]

Activity: a(x) = sign(〈~e, ~w 〉 − θ) = 2(〈~e, ~w 〉 − θ ≥ 0)− 1

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 23 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Bipolar and Binary Threshold Function

a(x) = sign(x) : R→[−1, 1]

Activity: a(x) = sign(〈~e, ~w 〉 − θ) = 2(〈~e, ~w 〉 − θ ≥ 0)− 1

Alternative Activities:a(x) = (x ≥ 0) = 1+sign(x)

2 = 〈x − 0〉0 : R→[0, 1]

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 23 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Bipolar and Binary Threshold Function

a(x) = sign(x) : R→[−1, 1]

Activity: a(x) = sign(〈~e, ~w 〉 − θ) = 2(〈~e, ~w 〉 − θ ≥ 0)− 1

Linear SeparationThreshold neurons linearly separate input data, logically combinedthreshold neurons define a simplex.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 23 / 48

Neurons and Neural Networks Artificial Neuron, Linear Seperation

Linearly separable Sets

Hidden neurons separate linearly

xy

−10

≥ 1.5

0

−10

= −1.5 x

y

0−1

≥ 01.5

0−1

= −1.5 x

y

11

≥ 31.5

11

= 4.5

The output neuron gathers these results usingthe logical OR-function.A positive answer (o = 1) signals that theelement belongs to the outer region (positiveregion).

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 24 / 48

Neurons and Neural Networks Neural Network Learning

Multi-layered Feed Forward Networks

Feed forward network with topology 3-4-4-2

Learning: Change weights and threshold until the result satisfies.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 25 / 48

Neurons and Neural Networks Neural Network Learning

Multi-layered Feed Forward Networks

Feed forward network with topology 3-4-4-2

rûs Bpforw ein;anzs;aus;is;netanzsûÙÒbpanþausûnetûbpanÒ¡0þaus[1]ûÚôein¡Ú÷bpte ã Eing. trans.isû1DO4:ý(anzs<isûis+1)/UNDO4 ã Schleife ..uber Schichten: Ausgabenaus[is]ûÚ1ß1+*-bpap«Ønet[is]ûÚ(isØbpbi)+[1](rØbpgw)+.«(rûis-1)ØausþýDO4UNDO4:rûô(anzsØaus)¡Ú÷bpta

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 25 / 48

Neurons and Neural Networks Neural Network Learning

Topology of a Feed-forward Network

Theorem (Kolmogorow, 1957)Every vector-valued function f : [0, 1]n→Rm can be written as a 3-layerfeed-forward network with n input neurons, 2n + 1 hidden neurons and moutput neurons. The activation functions depend on f and n.

Remark1 The proof shows the existence in a non-constructive way.2 It does not give the activation functions.3 The theorem has no direct practical impact.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 26 / 48

Neurons and Neural Networks Neural Network Learning

Topology of a Feed-forward Network

Theorem (Kolmogorow, 1957)Every vector-valued function f : [0, 1]n→Rm can be written as a 3-layerfeed-forward network with n input neurons, 2n + 1 hidden neurons and moutput neurons. The activation functions depend on f and n.

ZusatzFür die stetige Funktion f : [−1, 1]n → [−1, 1] gibt es Funktionen g undgi (i = 1, . . . , 2n + 1) in einem Argument und Konstantenλj (j = 1, . . . , n) mit

f (x1, . . . , xn) =2n+1∑i=1

g

n∑j=1

λjgi (xj)

.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 26 / 48

Neurons and Neural Networks Neural Network Learning

Topology of a Feed-forward Network

Theorem (Kolmogorow, 1957)Every vector-valued function f : [0, 1]n→Rm can be written as a 3-layerfeed-forward network with n input neurons, 2n + 1 hidden neurons and moutput neurons. The activation functions depend on f and n.

Satz (Annäherung durch Netze)Jede Funktion kann durch Netze mit einer verdeckten Schicht angenähertwerden.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 26 / 48

Neurons and Neural Networks Neural Network Learning

Multi-layered Feed Forward Networks

Input layerContinuous input:Linear transformation into [-1; 1]Discrete input:One neuron per value, transformed onto -1,1

Multi-layer network

Output layer using a tangential activity functionTarget activities should be equally distributed in the interval[−0.6, 0.6]!The inverse of the output function could be:

f (x) =

[m, M] → [−0.6, 0.6]x 7→ −0.6 + 1.2

(x−mM−m

)s; s > 0

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 27 / 48

Neurons and Neural Networks Neural Network Learning

Multi-layered Feed Forward Networks

Input layerContinuous input:Linear transformation into [-1; 1]Discrete input:One neuron per value, transformed onto -1,1

Multi-layer network

Output layer using a tangential activity functionTarget activities should be equally distributed in the interval[−0.6, 0.6]!The inverse of the output function could be:

f (x) =

[m, M] → [−0.6, 0.6]x 7→ −0.6 + 1.2

(x−mM−m

)s; s > 0

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 27 / 48

Neurons and Neural Networks Neural Network Learning

Multi-layered Feed Forward Networks

Input layerContinuous input:Linear transformation into [-1; 1]Discrete input:One neuron per value, transformed onto -1,1

Multi-layer network

Output layer using a logarithmic activity functionTarget activities should be equally distributed in the interval [0.2, 0.8]!The inverse of the output function could be:

f (x) =

[m, M] → [0.2, 0.8]x 7→ 0.2 + 0.6

(x−mM−m

)s; s > 0

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 27 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

TargetChange the weights and thresholds in such a way that the errors in thetraining data get small.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 28 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

TargetChange the weights and thresholds in such a way that the errors in thetraining data get small.

Calculations

error: E (~w) = 12

n∑i=1‖~zi − ~oi (w)‖2

gradient: −−→grad w E (~w) =(∂E (~w)∂w1

,∂E (~w)∂w2

, . . . ,∂E (~w)∂w3

)

Delta-Rule (Gradient descent)

∆~w (t) = −σ−−→grad w E (~w); ~w (t) = ~w (t−1) + ∆~w (t) + µ∆~w (t−1)

σ decreasing, z.B. von 0.9 auf 0.1, µ increasing, z.B. µ = 1− σ.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 28 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

TargetChange the weights and thresholds in such a way that the errors in thetraining data get small.

Calculations

error: E (~w) = 12

n∑i=1‖~zi − ~oi (w)‖2

gradient: −−→grad w E (~w) =(∂E (~w)∂w1

,∂E (~w)∂w2

, . . . ,∂E (~w)∂w3

)Delta-Rule (Gradient descent)

∆~w (t) = −σ−−→grad w E (~w); ~w (t) = ~w (t−1) + ∆~w (t) + µ∆~w (t−1)

σ decreasing, z.B. von 0.9 auf 0.1, µ increasing, z.B. µ = 1− σ.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 28 / 48

Neurons and Neural Networks Neural Network Learning

Error Back Propagation

Step-by-step error back propagation using the net error δi :~δi := ∂E

∂~ni= ∂E

∂~ni+1· ∂~ni+1∂~oi

· ∂~oi∂~ni

= ~δi+1 ·Wi+1 · A(~ni )

∂E∂Wi ,rs

= ∂E∂~ni· ∂~ni∂Wi ,rs

= ~δi · oi−1,s er = δi ,r oi−1,s

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 29 / 48

Neurons and Neural Networks Neural Network Learning

Error Back Propagation

Step-by-step error back propagation using the net error δi :~δi := ∂E

∂~ni= ∂E

∂~ni+1· ∂~ni+1∂~oi

· ∂~oi∂~ni

= ~δi+1 ·Wi+1 · A(~ni )

∂E∂Wi ,rs

= ∂E∂~ni· ∂~ni∂Wi ,rs

= ~δi · oi−1,s er = δi ,r oi−1,s

rûziel Bpback aus;anzs;dgwa;err;is;lr(aus lr)ûauserrûbpanÒ¡0dgwaûdgw ã dgw globalisûanzsûÙÒbpan ã Anzahl SchichtenrûanzsØaus ã Fehler letzte Schichterr[anzs]ûÚ-2«bpap«(r«1-r)«ziel-r ã NettofehlerDO:ý(1>isûis-1)/UNDO ã B.P. ..uber alle Sch.dgw[is]ûÚ(-(1+is)Øerr)Ê.«rûisØaus ã ÈGewicht je Schichtâ(is>1)/'err[is]ûÚbpap«(r«1-r)«(ôisØbpgw)+.«Øerr[1+is]' ã NettofehlerýDOUNDO:bpgwûbpgw+lr«dgw+(1-lr)«dgwa ã Gewichte ..andernbpbiûbpbi+(dbiû-lr«err)+(1-lr)«dbi ã Bias ..andernrûanzsØerr ã Fehler in letzter Sch.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 29 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

Levenberg-Marquardt-Method

E (~w) = 12

⟨~f (~w), ~f (~w)

⟩mit ~f (~w) = ~z − ~o(~w)

~0 = E ′(~w) = −−→grad E (~w) = f ′T (~w)~f (~w)E ′′(~w) = f ′T (~w)f ′(~w) für f ′′T (~w) small!~wk+1 = ~wk − E ′′(~w)−1E ′(~w)

∆~w = −(

f ′T (~w)f ′(~w))−1

f ′T (~w)~f (~w)

System of linear equations to be solved:

f ′T (~w)f ′(~w)∆~w = −f ′T (~w)~f (~w)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 30 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

Levenberg-Marquardt-Method

E (~w) = 12

⟨~f (~w), ~f (~w)

⟩mit ~f (~w) = ~z − ~o(~w)

~0 = E ′(~w) = −−→grad E (~w) = f ′T (~w)~f (~w)

E ′′(~w) = f ′T (~w)f ′(~w) für f ′′T (~w) small!~wk+1 = ~wk − E ′′(~w)−1E ′(~w)

∆~w = −(

f ′T (~w)f ′(~w))−1

f ′T (~w)~f (~w)

System of linear equations to be solved:

f ′T (~w)f ′(~w)∆~w = −f ′T (~w)~f (~w)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 30 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

Levenberg-Marquardt-Method

E (~w) = 12

⟨~f (~w), ~f (~w)

⟩mit ~f (~w) = ~z − ~o(~w)

~0 = E ′(~w) = −−→grad E (~w) = f ′T (~w)~f (~w)

E ′′(~w) =(

f ′T (~w)~f (~w))′

= f ′′T (~w)~f (~w) + f ′T (~w)f ′(~w)

= f ′T (~w)f ′(~w) für f ′′T (~w) small!

~wk+1 = ~wk − E ′′(~w)−1E ′(~w)

∆~w = −(

f ′T (~w)f ′(~w))−1

f ′T (~w)~f (~w)

System of linear equations to be solved:

f ′T (~w)f ′(~w)∆~w = −f ′T (~w)~f (~w)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 30 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

Levenberg-Marquardt-Method

E (~w) = 12

⟨~f (~w), ~f (~w)

⟩mit ~f (~w) = ~z − ~o(~w)

~0 = E ′(~w) = −−→grad E (~w) = f ′T (~w)~f (~w)

E ′′(~w) =(

f ′T (~w)~f (~w))′

= f ′′T (~w)~f (~w) + f ′T (~w)f ′(~w)

= f ′T (~w)f ′(~w) für f ′′T (~w) small!~wk+1 = ~wk − E ′′(~w)−1E ′(~w)

∆~w = −(

f ′T (~w)f ′(~w))−1

f ′T (~w)~f (~w)

System of linear equations to be solved:

f ′T (~w)f ′(~w)∆~w = −f ′T (~w)~f (~w)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 30 / 48

Neurons and Neural Networks Neural Network Learning

Learning in multi-layered networks

Levenberg-Marquardt-Method

E (~w) = 12

⟨~f (~w), ~f (~w)

⟩mit ~f (~w) = ~z − ~o(~w)

~0 = E ′(~w) = −−→grad E (~w) = f ′T (~w)~f (~w)E ′′(~w) = f ′T (~w)f ′(~w) für f ′′T (~w) small!~wk+1 = ~wk − E ′′(~w)−1E ′(~w)

∆~w = −(

f ′T (~w)f ′(~w))−1

f ′T (~w)~f (~w)

System of linear equations to be solved:

f ′T (~w)f ′(~w)∆~w = −f ′T (~w)~f (~w)

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 30 / 48

Neurons and Neural Networks Neural Network Learning

Evaluation of a trained network

Error in training datamaximal errormean errorstandard deviation

InsiderEvaluation of forecasts

Error in testing data20%-40% of available datamaximal and mean errorstandard deviation

Auto correlation

KNNKNN

e

fo

fe

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 31 / 48

Neurons and Neural Networks Neural Network Learning

Evaluation of a trained network

Error in training datamaximal errormean errorstandard deviation

InsiderEvaluation of forecasts

Error in testing data20%-40% of available datamaximal and mean errorstandard deviation

Auto correlation

KNNKNN

e

fo

fe

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 31 / 48

Neurons and Neural Networks Neural Network Learning

Evaluation of a trained network

Error in training datamaximal errormean errorstandard deviation

InsiderEvaluation of forecasts

Error in testing data20%-40% of available datamaximal and mean errorstandard deviation

Auto correlation

KNNKNN

e

fo

fe

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 31 / 48

Neurons and Neural Networks Neural Network Learning

Evaluation of a trained network

Error in training datamaximal errormean errorstandard deviation

InsiderEvaluation of forecasts

Error in testing data20%-40% of available datamaximal and mean errorstandard deviation

Auto correlation

KNNKNN

e

fo

fe

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 31 / 48

Accident Severity Prediction of Accident Severity

1 Analysis, Modelling and Solutions

2 Neurons and Neural Networks

3 Accident SeverityPrediction of Accident SeverityLearning Strategy

4 Comfort in Cabriolet: Active Torsion Damping

5 Further Examples and Conclusion

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 32 / 48

Accident Severity Prediction of Accident Severity

Accident Severity with A. Kuhn, J. Urbahn, BMW AG, 2000

t0: decision to fire airbag ...

tZ : ignition of airbag(t1 − tZ ≈ 30ms)

t1: driver starts forwarddisplacement

t2: acceleration decreases

Targets1 predict the severity of the accident2 help deciding which action to be taken3 protect the passengers as good as possible

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 33 / 48

Accident Severity Prediction of Accident Severity

Accident Severity with A. Kuhn, J. Urbahn, BMW AG, 2000

t0: decision to fire airbag ...

tZ : ignition of airbag(t1 − tZ ≈ 30ms)

t1: driver starts forwarddisplacement

t2: acceleration decreases

Targets1 predict the severity of the accident2 help deciding which action to be taken3 protect the passengers as good as possible

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 33 / 48

Accident Severity Prediction of Accident Severity

Targets of the Project

Accident severity: possible parameters

1 (mean) velocity of passengers (time, forwarddisplacement)

2 mean acceleration of passengers

Data baseData from parameter variations with Monte-Carlomethod:1 variation of relevant parameters and testing mode2 FEM simulations using PamCrash3 150 - 300 data sets for every 14 models

Data from some real crash tests

Made possible by

more computer power!

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 34 / 48

Accident Severity Prediction of Accident Severity

Targets of the Project

Accident severity: possible parameters

1 (mean) velocity of passengers (time, forwarddisplacement)

2 mean acceleration of passengers

Data baseData from parameter variations with Monte-Carlomethod:1 variation of relevant parameters and testing mode2 FEM simulations using PamCrash3 150 - 300 data sets for every 14 models

Data from some real crash tests

Made possible by

more computer power!

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 34 / 48

Accident Severity Prediction of Accident Severity

Targets of the Project

Accident severity: possible parameters

1 (mean) velocity of passengers (time, forwarddisplacement)

2 mean acceleration of passengers

Data baseData from parameter variations with Monte-Carlomethod:1 variation of relevant parameters and testing mode2 FEM simulations using PamCrash3 150 - 300 data sets for every 14 modelsData from some real crash tests

Made possible by

more computer power!

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 34 / 48

Accident Severity Prediction of Accident Severity

Targets of the Project

Accident severity: possible parameters

1 (mean) velocity of passengers (time, forwarddisplacement)

2 mean acceleration of passengers

Data baseData from parameter variations with Monte-Carlomethod:1 variation of relevant parameters and testing mode2 FEM simulations using PamCrash3 150 - 300 data sets for every 14 modelsData from some real crash tests

Made possible by

more computer power!

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 34 / 48

Accident Severity Prediction of Accident Severity

Using the Power of Neural Networks

3- or 4-layer networks Input

accelerations, velocities, dis-placementsmaximal and mean values

Output

1 velocity2 mean acceleration

(impact to passengers)

Learning:

activation function: tangential, piecewise parabolalearning method: gradient descent, Levenberg-Marquardt

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 35 / 48

Accident Severity Prediction of Accident Severity

Using the Power of Neural Networks

3- or 4-layer networks Input

accelerations, velocities, dis-placementsmaximal and mean values

Output

1 velocity2 mean acceleration

(impact to passengers)

Learning:

activation function: tangential, piecewise parabolalearning method: gradient descent, Levenberg-Marquardt

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 35 / 48

Accident Severity Prediction of Accident Severity

Using the Power of Neural Networks

3- or 4-layer networks Input

accelerations, velocities, dis-placementsmaximal and mean values

Output

1 velocity2 mean acceleration

(impact to passengers)

Learning:

activation function: tangential, piecewise parabolalearning method: gradient descent, Levenberg-Marquardt

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 35 / 48

Accident Severity Learning Strategy

Training the Networks: Learning Strategy

random choice of 60% learning, 40% testing datastop training when the error in testing data increases

Mean learning error

0 10 20 30 40 50 60 70 8010

−5

10−4

10−3

10−2

10−1

100

Performance is 0.00631592, Goal is 1e−005

81 Epochs

Tra

inin

g−B

lue

Goa

l−B

lack

Val

idat

ion−

Gre

en T

est−

Red

Weights in the first layer

0 1 2 3 4 5 6 7

1

2

3

4

Input

Neu

ron

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 36 / 48

Accident Severity Learning Strategy

Training the Networks: Influence of the Input

random choice of 60% learning, 40% testing datastop training when the error in testing data increases

Mean learning error

0 10 20 30 40 50 60 70 8010

−5

10−4

10−3

10−2

10−1

100

Performance is 0.00631592, Goal is 1e−005

81 Epochs

Tra

inin

g−B

lue

Goa

l−B

lack

Val

idat

ion−

Gre

en T

est−

Red

Weights in the first layer

0 1 2 3 4 5 6 7

1

2

3

4

Input

Neu

ron

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 36 / 48

Accident Severity Learning Strategy

Optimization

Statistics on the number of neurons (1 - 2 hidden layers)

0 50 100 150 200 250 3000

Anzahl der Gewichte

σ(fe

hler

)

Standardabweichungen: µ(σ(fehler)) ± σ(σ(fehler))

LerndatenTestdaten

0 50 100 150 200 250 300

100

Anzahl der Gewichte

cor(

a,z)

Korrelationen: µ cor(a,z) ± σ cor(a,z)

LerndatenTestdaten

Graphs:σ(σ(oi − zi ))correlation

Expectation:σ(σ) gets smaller upto saturation.error in learning dataonly a bit better thantesting data

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 37 / 48

Accident Severity Learning Strategy

Results

Models1 FEM simulation data gives a good data base.2 Usable topologies: e.g.: 4-15-8-1, 4-33-13 Usable parameter: mean acceleration4 Usable input:mean accelerations and velocities

σ2-method allows:to choose a network of an appropriate size.to judge on the quality of the data.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 38 / 48

Accident Severity Learning Strategy

Results

Models1 FEM simulation data gives a good data base.2 Usable topologies: e.g.: 4-15-8-1, 4-33-13 Usable parameter: mean acceleration4 Usable input:mean accelerations and velocities

σ2-method allows:to choose a network of an appropriate size.to judge on the quality of the data.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 38 / 48

Comfort in Cabriolet: Active Torsion Damping Disturbance of Comfort

1 Analysis, Modelling and Solutions

2 Neurons and Neural Networks

3 Accident Severity

4 Comfort in Cabriolet: Active Torsion DampingDisturbance of ComfortActive Torsion Damping using Neural networks

5 Further Examples and Conclusion

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 39 / 48

Comfort in Cabriolet: Active Torsion Damping Disturbance of Comfort

Active Damping of Torsion with Ch. Hornung, G. Pflanz, BMW AG, 2005

Problem of a Cabrio: lack of torsion stiffness Mx/dy

Limousine: 100 % Cabrio 7.3%

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 40 / 48

Comfort in Cabriolet: Active Torsion Damping Disturbance of Comfort

Origin of Unwanted Vibration

AnregungCar excitation mainly caused bywheel resonance,

⇒ Excitation is transmitted by jointsthrough the axes and spring strut,

⇒ Vibration is observed by passengers.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 41 / 48

Comfort in Cabriolet: Active Torsion Damping Disturbance of Comfort

Origin of Unwanted Vibration

AnregungCar excitation mainly caused bywheel resonance,

⇒ Excitation is transmitted by jointsthrough the axes and spring strut,

⇒ Vibration is observed by passengers.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 41 / 48

Comfort in Cabriolet: Active Torsion Damping Disturbance of Comfort

Origin of Unwanted Vibration

AnregungCar excitation mainly caused bywheel resonance,

⇒ Excitation is transmitted by jointsthrough the axes and spring strut,

⇒ Vibration is observed by passengers.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 41 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Active Damping: Actuators produce counter-displacement

Sensors and ActuatorsSensors realize a disturbanceActuators produce opposite displacement

⇒ No displacement at the windscreen panel

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 42 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Active Damping: Actuators produce counter-displacement

Sensors and ActuatorsSensors realize a disturbanceActuators produce opposite displacement

⇒ No displacement at the windscreen panel

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 42 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Active Damping: Actuators produce counter-displacement

Sensors and ActuatorsSensors realize a disturbanceActuators produce opposite displacement

⇒ No displacement at the windscreen panel

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 42 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Training

and Results

Models

One or all velocities

Time series up to 500 ms

Combination of accelerations

Training of the neural networks

At least 40% data for testing

Gradient descent,Levenberg-Marquardt

Termination:errors in testing data increase

Good results

time series ca. 200 ms ,

2 and 4 input signals,

both training methods

small networks ⇒ strongly linearbehaviour of car body and actuator

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 43 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Training

and Results

Models

One or all velocities

Time series up to 500 ms

Combination of accelerations

Training of the neural networks

At least 40% data for testing

Gradient descent,Levenberg-Marquardt

Termination:errors in testing data increase

Good results

time series ca. 200 ms ,

2 and 4 input signals,

both training methods

small networks ⇒ strongly linearbehaviour of car body and actuator

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 43 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Training and Results

Models

One or all velocities

Time series up to 500 ms

Combination of accelerations

Training of the neural networks

At least 40% data for testing

Gradient descent,Levenberg-Marquardt

Termination:errors in testing data increase

Good results

time series ca. 200 ms ,

2 and 4 input signals,

both training methods

small networks ⇒ strongly linearbehaviour of car body and actuator

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 43 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Validation

ValidationIntegration of trained network into a simulink-modelNeural network gives slightly better results than a linear control

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 44 / 48

Comfort in Cabriolet: Active Torsion Damping Active Torsion Damping using Neural networks

Validation

ValidationIntegration of trained network into a simulink-modelNeural network gives slightly better results than a linear control

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 44 / 48

Further Examples and Conclusion Further Example

1 Analysis, Modelling and Solutions

2 Neurons and Neural Networks

3 Accident Severity

4 Comfort in Cabriolet: Active Torsion Damping

5 Further Examples and ConclusionFurther ExampleConclusion

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 45 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Controlling vehicles and robotsNeural Network controls a vehicle orrobot. It is trained „on the job“.

Insolvency DetectionBased on annual reports a forecaston the risque of insolvency is given.

Potential terminationBased on power consumption andclient data companies that mightterminate a contract are identifiedand get discount.

Forecast of share valueForecast based on previous share val-ues and economic data of the com-pany.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Controlling vehicles and robotsNeural Network controls a vehicle orrobot. It is trained „on the job“.

Insolvency DetectionBased on annual reports a forecaston the risque of insolvency is given.

Potential terminationBased on power consumption andclient data companies that mightterminate a contract are identifiedand get discount.

Forecast of share valueForecast based on previous share val-ues and economic data of the com-pany.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Controlling vehicles and robotsNeural Network controls a vehicle orrobot. It is trained „on the job“.

Insolvency DetectionBased on annual reports a forecaston the risque of insolvency is given.

Potential terminationBased on power consumption andclient data companies that mightterminate a contract are identifiedand get discount.

Forecast of share valueForecast based on previous share val-ues and economic data of the com-pany.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Controlling vehicles and robotsNeural Network controls a vehicle orrobot. It is trained „on the job“.

Insolvency DetectionBased on annual reports a forecaston the risque of insolvency is given.

Potential terminationBased on power consumption andclient data companies that mightterminate a contract are identifiedand get discount.

Forecast of share valueForecast based on previous share val-ues and economic data of the com-pany.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Chemical reactivityPredection of its reactivity fromqauntivative properties of a bonding.

Insolvency DetectionBased on annual reports a forecaston the risque of insolvency is given.

Potential terminationBased on power consumption andclient data companies that mightterminate a contract are identifiedand get discount.

Forecast of share valueForecast based on previous share val-ues and economic data of the com-pany.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Chemical reactivityPredection of its reactivity fromqauntivative properties of a bonding.

Origin of olive oilThe concentration of acids deter-mines the origin (region) of Italianolive oil.

Potential terminationBased on power consumption andclient data companies that mightterminate a contract are identifiedand get discount.

Forecast of share valueForecast based on previous share val-ues and economic data of the com-pany.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Chemical reactivityPredection of its reactivity fromqauntivative properties of a bonding.

Origin of olive oilThe concentration of acids deter-mines the origin (region) of Italianolive oil.

OlfaktometerMicro crystal system with six differ-ent piezo-electric crystal sensors: Aneural network learns to recognizeflavours.

Forecast of share valueForecast based on previous share val-ues and economic data of the com-pany.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Chemical reactivityPredection of its reactivity fromqauntivative properties of a bonding.

Origin of olive oilThe concentration of acids deter-mines the origin (region) of Italianolive oil.

OlfaktometerMicro crystal system with six differ-ent piezo-electric crystal sensors: Aneural network learns to recognizeflavours.

Structure of a proteinConclusion from the primary struc-ture of a protein to its secondaryspacial structure.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Power consumptionPrediction of the power consumptionof companies from one year to thenext.

Origin of olive oilThe concentration of acids deter-mines the origin (region) of Italianolive oil.

OlfaktometerMicro crystal system with six differ-ent piezo-electric crystal sensors: Aneural network learns to recognizeflavours.

Structure of a proteinConclusion from the primary struc-ture of a protein to its secondaryspacial structure.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Power consumptionPrediction of the power consumptionof companies from one year to thenext.

Neural stetoscopeA neural networks interprets thenoise coming through a stethoscopeand provides a diagnoses of a heartproblem.

OlfaktometerMicro crystal system with six differ-ent piezo-electric crystal sensors: Aneural network learns to recognizeflavours.

Structure of a proteinConclusion from the primary struc-ture of a protein to its secondaryspacial structure.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Further Example

Pattern Recognition

Power consumptionPrediction of the power consumptionof companies from one year to thenext.

Neural stetoscopeA neural networks interprets thenoise coming through a stethoscopeand provides a diagnoses of a heartproblem.

Breaking torqueDetermining the breaking torquefrom hydraulic pressure and velocity.

Structure of a proteinConclusion from the primary struc-ture of a protein to its secondaryspacial structure.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 46 / 48

Further Examples and Conclusion Conclusion

Conclusion

Neuronal networks are able tolearn and store know how of a system,map functional dependencies

using a smooth or balancing interpolation between sampling points.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 47 / 48

Further Examples and Conclusion Conclusion

Conclusion

Neuronal networks are able tolearn and store know how of a system,map functional dependencies

using a smooth or balancing interpolation between sampling points.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 47 / 48

Further Examples and Conclusion Conclusion

Conclusion

Neuronal networks are able tolearn and store know how of a system,map functional dependencies

using a smooth or balancing interpolation between sampling points.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 47 / 48

Further Examples and Conclusion Conclusion

Conclusion

Neuronal networks are able tolearn and store know how of a system,map functional dependencies

using a smooth or balancing interpolation between sampling points.

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 47 / 48

Further Examples and Conclusion Conclusion

Thank you for listening to my talk!

Dieter Kilsch (eh. TH Bingen) Feed-Forward Neural Networks 28.11.2016 48 / 48

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