vorlesung grundzüge der wirtschaftsinformatik w1311 · 2017-06-13 · vorlesung grundzüge der...
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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
16. Planung von Investitionsalternativen
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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!
16. Planung von Investitionsalternativen
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
16. Planung von Investitionsalternativen
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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
Suitability forseries production
PrincipalSuitability
DevelopmentStage II
DevelopmentStage III
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
16. Planung von Investitionsalternativen – Development Process
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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
16. Planung von Investitionsalternativen – Development Process
• 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
16. Planung von Investitionsalternativen – Development Process
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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?
16. Planung von Investitionsalternativen – Development Process
• 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?
16. Planung von Investitionsalternativen – Development Process
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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
16. Planung von Investitionsalternativen – Development Process
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
Suitability forseries production
PrincipalSuitability
DevelopmentStage II
DevelopmentStage III
Evaluation Evaluation Evaluation
New Alternative
Bad Alternative
16. Planung von Investitionsalternativen – Development Process
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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
• Not suitable for qualitative criteria
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
• Not suitable for qualitative criteria
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
16. Planung von Investitionsalternativen
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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)
16. Planung von Investitionsalternativen
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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
16. Planung von Investitionsalternativen
Own Approach to Decision Support
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
16. Planung von Investitionsalternativen
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Own Approach to Decision Support
• 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
16. Planung von Investitionsalternativen
Own Approach to Decision Support
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
16. Planung von Investitionsalternativen
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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
16. Planung von Investitionsalternativen
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
16. Planung von Investitionsalternativen
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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
16. Planung von Investitionsalternativen