Vorlesung Grundzüge der Wirtschaftsinformatik W1311 · 2017-06-13 · Vorlesung Grundzüge der Wirtschaftsinformatik W1311 Fakultät für Wirtschaftswissenschaften ... 11. Kommunikationssysteme,

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VorlesungGrundzüge der WirtschaftsinformatikW1311Fakultät für Wirtschaftswissenschaften

W. Dangelmaier

1. Einführung: Worum geht es hier?2. System3. Modell4. Modellierung von Gegenständen5. Strukturmodelle (Gebildestruktur)6. Verhaltensmodelle (Prozessstruktur)7. Produktion8. Digitale Fabrik9. Datenorganisation und Datenmanagement10. Datenintegration/Funktionsintegration11. Kommunikationssysteme, Internet, World Wide Web und Lab 2.012. E-Commerce / E-Business 13. IT-Governance14. Systementwicklung15. Entscheidungsunterstützung16. Planung von Investitionsalternativen17. Wirtschaftlichkeitsrechnung18. Glossar

Grundzüge der Wirtschaftsinformatik - Inhalt

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Development…

or

Improvement…

…of production technologiesand manufacturing processes

in the automotive industry

It is impossible…

or

It would not be cost-efficient…

…to produce a specificautomotive product/part

with existing manufacturing technologies and processes

The example on the next slides is a simplified version of the real world problem. It is based on actual research activities of an engineering team at the Daimler Research and Development Center in Ulm.

16. Planung von Investitionsalternativen

• In order to reduce carbon dioxide emissions, the weight of cars has to be lowered

• Therefore, some of the outer shell parts will be made of polymers or carbon fiber composites

Tailgate structuremade of carbonfiber composites

Door structuremade of polymers

Example


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Replanning of an Automotive Paint Shop – Reasons

Problems caused by the substitution of steel and aluminium parts with parts made of polymers and carbon fibre composites:

• No phosphating needed, but additional flame treatment necessary• No cathodic electro deposition needed to prevent corrosion• Paint drying ovens exceed the thermal limit of the new materials, bypass needed

From Body Shop To Assembly LineCleaning &

PhosphatingCathodic Electro

Deposition Seam SealingColour Top Coat

& Clear Coat

Structure and technologies of the paint shop have to be changed!


Pre-Assembly Doors

Stamping Plant

RTM - Doors

Assembly Line

Replanning of an Automotive Paint Shop – Concepts

Body Shop Paint Shop

Offline Process (Example: Doors)

Online Process (Example: Doors)

BS - Doors PS - Doors

Stamping Plant Assembly LineBody Shop Paint Shop

Door Cell

CED/DrierPre-Assembly Doors

RTM - Doors

• MIN-Process• As little changes as

possible• Even the existing

pre-assembly line could be used

• Only the critical points are bypassed

• Use of adapter constructions

• MAX-Process• Completely

separate production of car body and doors

• Doors are delivered just in sequence


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Start ofDevelopment

DevelopmentStage I

ConceptualSuitability

Suitability forseries production

PrincipalSuitability

DevelopmentStage II

DevelopmentStage III

Stages of a Typical Research/Development Process in the Automotive Industry

• Concept (idea, virtual)• Virtual tests on basic

functionality

• Prototype (real, rough)• Experiments on basic

functionality

• Prototype (real, detailed)• Experiments on process

steps for serial production

Tech

nolo

gyPr

oces

s

• Concept (ideal) • Ideal layout & capacity plan • Real layout & simulations

16. Planung von Investitionsalternativen – Development Process

Start ofDevelopment

DevelopmentStage I

ConceptualSuitability



DevelopmentStage II


High Development Effort due to a high Number of Alternatives

High development effort if every alternative has to be developed until suitability for series

Sometimes, there is more than one technical solution for a problem

On every development stage,sub-concepts can emerge


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• There are two possible solutions (basic ideas) how to attach the doors/tailgate/hood

• Which technology should be developed or used?

One single adapter for all parts One separate adapter for each single part

Example


• There are two possible logistic processes (basic ideas) for the transport of adapters from assembly to body shop

• Which process should be used?

Transport on existing skid Transport with electric monorail system


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Outer Adapter(adapter outside the chassis,

mounted on the transportation skid)

Inner Adapter(adapter inside the chassis,

attached to the car itself)

Bridge Adapter(adapter inside the chassisbut mounted on the skid)

• There could also be sub-concepts for each of the basic technology concepts

• For example, in case of separate adapters, there are 3 different interface constructions for the doors (there are also several sub-concepts for tailgate and hood)

• Which technology should be developed or used?


• Each of the adapter sub-concepts could be combined with several mechanisms to realize different degrees of freedom in order to open and move the doors

• For example, in case of outer adapters, there are 2 different mechanisms for the doors (there are also several different mechanisms for tailgate and hood)

• Which one should be developed or used?


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• For each handling process, there are several possible layout concepts

• For example, in case of outer adapters, the detaching of the doors can be done in 2 ways

• Which one should be developed or used?

Handling/layout concept A Handling/layout concept B

In order to reduce the development effort, the number of alternatives(including sub-concepts) must be reduced from stage to stage


Stage I: Evaluation of basic technology concepts/ideas and basis manufacturing processesStage II: Evaluation of detailed technology concepts and advanced processes (e.g. ideal layouts)Stage III: Evaluation of detailed technology concepts and detailed processes (e.g. real layouts)

Advantage: Less effort and better technologies compared to a process with only one final evaluation

Technological Uncertainty

Reduction of Development Effort by Evaluation (Multi-Stage Decision Support)Start of

DevelopmentDevelopment

Stage IConceptualSuitability



DevelopmentStage II


Evaluation Evaluation Evaluation

New Alternative

Bad Alternative


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Technical Risks:

In early stages of the development process, some parameters of the developed technology are not certain because not every aspect has been tested in an experiment or simulated until then

Example: stability of interface constructions, buffer sizes, cycle times for handling processes

Monetary Risks:

In most cases there is only little information about the later costs of technologies if they are still under development

Example: costs of interface constructions for series production (not the costs of prototypes)

Circumstantial Risks:

In case of fundamental technology research there is not always a clear application scenario

Example: uncertainty about the first application for coating adapters (product, number of pieces)

P1 P2P3 P4

P5

Alternative A2

Principal SuitabilityConceptual SuitabilitySuitability for Series ProductionUncertainty

(Assumptionsnecessary inorder to evaluatethe alternative)

P1 P2 P3P4

P5

Alternative A1

16. Planung von Investitionsalternativen – Unvertainty

Difference between decision support for planning and development processes:

Planning Process:

• Production technologies and their characteristics/features cannotbe changed

• It exists only one evaluation criteria: costs

• State of the Art Method: linear programming (MILP) for cost optimization

Development Process:

• Production technology is still under development and characteristics/features can be changed by engineering

• It exists more than one evaluation criteria:e.g. costs, flexibility, performance, compatibility of technologies, quality

Which method should be used for decision support (evaluation)?

16. Planung von Investitionsalternativen – Methods and Criteria

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A multi-stage and multi-criteria Approach to Decision Support for the Developmentof Production Technologies and Manufacturing Processes in the Automotive Industry

There can be many alternative technologies Iterative evaluation on multiple stagesrespectively with several process alternatives in order to reduce the development effort

The uncertainty (circumstantial, technical and Assumptions have to be replaced with factsmonetary risk) is reduced from stage to stage based on a modular design (vertically)

Technologies are under development, so their Evaluation of multiple criteria (not only costs)characteristics and features can be changed is required to provide appropriate feedback

The structure of alternative processes The evaluation model must be extendable andcan be totally different and it can change should have a modular design (horizontally)

Decisions are made by persons, not by the It should be possible to aggregate the detailed evaluation method information for management suitability

Summary Requirements

16. Planung von Investitionsalternativen –Requirements for the Evaluation Method

Common Methods Basic Principle ProblemVector Optimization(a.k.a Pareto Optimization)

• A priori weighting (weighted sum of the objectives)• Determination of pareto-efficient solutions

• Not suitable for qualitative criteria

Goal Programming• A priori weighting• Minimization of a distance index to a target value


Utility Analysis• A priori weighting of criteria• Utility based scoring method

• See example

Analytic Hierarchy Process(AHP)

• A priori weighting of criteria (hierarchical structure)• Determination of a utility value based on pairwise comparison

• See example

Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE)

• A priori weighting of criteria• Outranking relation based on the determination of distance

indices (by pairwise comparison)• See example

Elimination et Choix Traduisant la Réalité(ELECTRE)

• A priori weighting of criteria• Outranking relation based on pairwise comparison

• See example

Technique for Order Preference by Similarity to Ideal Solution (TOPSIS)

• A priori weighting of criteria• Determination of a distance index to best/worst value


State of the Art - Multi Criteria Decision Making (MCDM)

One of the problems:

How to evaluate alternative technologies based on multiple criteria

First idea:

Based on a literature research, using a MCDM method is state of the art


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Simplified Decision Problem

A1: Outer Adapter c1: Costs

A2: Inner Adapter c2: Flexibility

c3: Quality

Weighting of Criteria(Pairwise Comparison)

c1 c2 c3 w

c1 1 6 2 0,6

c2 1/6 1 1/3 0,1

c3 1/2 3 1 0,3

ExampleUtility Based Evaluation

This example shall illustrate some basic problems with MCDM methods

Based on the Utility Analysis It refers to the Utility Analysis but even newer methods like PROMETHEE and ELECTRE have the same problems

Utility based evaluation methods assume independency of all criteria which is not always possible in real world problems

It is not sure if the decision maker is able to express his preferences in a quantitative way (pseudo-accuracy)

An interval scale is used and only integer values are allowed (1-9) which means that a criterion can only be equally important to or at least twice as important as another one

State of the Art - Multi Criteria Decision Making (MCDM)16. Planung von Investitionsalternativen

Evaluation of Alternatives(Direct Choice)

c1 w1 c2 w2 c3 w3 s

A1 4 0,6 9 0,1 6 0,3 5,1

A2 2 0,6 2 0,1 8 0,3 3,8

Results

Outer Adapter: 5,1

Inner Adapter: 3,8

Outer Adapter is the better choice

There is a huge loss of information and a compensation effect due to aggregation

The method does not explain how to determine the values of qualitative criteria (e.g. flexibility)

It is not sure if the decision maker is able to express his preferences in a quantitative way (pseudo-accuracy)

The method does not take into account that the technologies are still under development and their characteristic and features can be changed (choice instead of multi-criteria feedback to developers)

State of the Art - Multi Criteria Decision Making (MCDM)


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Own Approach to Decision Support

Example:

• E-/SL-/CLS-Class (300.000/20.000/30.000 p.a.)

• Interface constructions needed for doors and tailgate

• Adapters have to be decoated on every second cycle

C1 C2C3 C4

C5 Principal Suitability

Conceptual Suitability

Suitability for Series Production

Uncertainty(Assumptionsnecessary inorder to evaluatethe alternative)

Establishment of Comparability

Because of the uncertainty in early stages of a development process, assumptions have to be made in order to be able to evaluate and compare different alternatives

• Definition of a realistic reference scenario based on strategic goals and existing manufacturing processes(e.g. number and sort of production series and components, number of pieces)

• The reference scenario should be updated on every development stage or iteration of evaluation

• Assumptions for technical characteristics



Evaluation of Costs, Flexibility and PerformanceProduction costs depend on several parameters which must be analyzed

• The cost model has a modular design which allows to extend the model horizontally and vertically

• Each element has the necessary attributes for its costs which allows to sum up cost types or cost centers in order to identify cost drivers

• Technical risks like the amount of required raw materials or staff are analyzed by a sensitivity analysis

• Furthermore, the performance and flexibility of the developed process can be analyzed by varying cycle times and changing the reference scenario

• It is important to determine technical restrictions like the maximal amount of parallel stations

• These analysis provide feedback for the next development stage

Example for attributes:- Amount of raw materials- Price of raw materials- Staff requirement- Wages- Capital cost- Amortization period


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• Monetary risks like the costs of machines which are under development or the prices of raw materials are analyzed using a risk analysis

• Therefore, distribution functions of the uncertain parameters have to be approximated

• The consolidation of these distribution functions is done by using the Monte Carlo Simulation Method

Example:

• Simultaneous variation of the number of production series and the number of pieces

• This allows to determine the best- and worst-case scenario for different manufacturing concepts



Evaluation of Quality and Compatibility of Technologies and ProcessesThe impact of a new technology or manufacturing process on product quality and other technologies can be evaluated using the method of Failure Mode and Effects Analysis (FMEA) and material flow simulations

• The impact of a technology on other process steps and buffer sizes is determined using a Plant Simulation Model

• The compatibility of a new technology with existing technologies and processes is done using the System Failure Mode and Effects Analysis Method (S-FMEA)

• Severity: 1 to 10

• Occurrence: 1 to 10

• Detection: 1 to 10

• Risk Priority Number (RPN) = S * O * D


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ProblemstellungBewertung von Fertigungstechnologien und Fabrikkonzepten

• Technischer Hintergrund: Entwicklung neuer Fertigungstechnologien und der dazugehörigen

Prozessketten (Fabriklayout und Ablauf)

• Entscheidungsproblem: Identifikation der besten Alternative im Falle mehrerer technischer

Konzepte

• Beispiel: Unterschiedliche Legetechnologien für die verschnittfreie CFK-Fertigung und

dazugehörige Groblayouts

Mehrstufige Methode zur entwicklungsbegleitenden Entscheidungsunterstützung


Alternative A2:

Technologie: Printer

Prozess: Variante B

Alternative A1:

Technologie: Printer

Prozess: Variante A

Alternative A3:

Technologie: Plotter

Prozess: Variante A

Alternative A4:

Technologie: Flexpicker

Prozess: Variante A

Mehrstufige Methode zur entwicklungsbegleitenden Entscheidungsunterstützung


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Mehrstufige Methode zur entwicklungsbegleitenden EntscheidungsunterstützungGesamtvorgehenTrennung von technischen Prämissen und Kosten• Die Bewertung der Alternativen über einen Kostenvergleich, welcher um technische Bewertungsaussagen

ergänzt wird


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Vorlesung Grundzüge der Wirtschaftsinformatik W1311 · 2017-06-13 · Vorlesung Grundzüge der Wirtschaftsinformatik W1311 Fakultät für Wirtschaftswissenschaften ... 11. Kommunikationssysteme,