Lecture 1 Flashcards
What steps does system analysis include?
- System Survey
- System modeling
What are common challenges in system development?
- Increased comlexity (e.g. SAP ERP)
- Increased quality standards
- Outsourced development
- Portablility (lifetime of software > hardware)
=> 84% of projects not completed as planned
What are common reasons for failure of development projects? How can they be mitigated?
- Legal regulations
- communitation between users and developers
- Complex requirements
- errors in specification often only apparent after implementation
=> system analysis necessary
How do errors accumulate during development?
Specification gaps and errors stay and impact other phases of development later
How do troubleshooting costs change in development phases?
Increase with further development
Was ist Systemanalyse?
Alle relevanten Informationen über ein System sammeln
Warum werden repräsentative Modelle für Systeme entwickelt?
- Verständnis erhöhen
- Kommunikation über das System erhöhen
- Systemverhalten und Änderungen untersuchen
- Basis für folgende Entwicklung
Was ist ein System?
Elemente, die über eine Zahl an Relationen verbunden sind.
(Zusätzlich Inputs und Outputs)
Wie kann ein System klassifiziert werden?
- Scope of being: real vs ideal
- Entwicklungsart: natürlich vs artificial
- Verbindung zur Umgebung: geschlossen vs offen
- Parameter-dependency of characteristics: static vs dynamic
Determinability of characteristics: deterministic vs stochastic
What is a model?
A system that was developed via a purposeful abstract reproduction of another system (Krallmann)
How do homomorphic and isomorphic reproductions of systems differ?
Homomorphic can skip parts / hide them via abstraction
Isomorphic is a direct representation
What are the phases and context of system analysis?
Phases: System survey and system modeling.
Context: Results of preliminary study are used, system model and specification are result of system analysis
What are techniques for information retrieval?
- Person-centered techniques: Interview, questionnaire, observation
- Document-related techniques: inventory, analysis and evaluation of sources
What is the inventory technique?
Document-centric technique. Extraction of low-level documents like:
* Organization plans
* Work instructions and process directives
* Forms, statistics
* System and program documentation
What is the analysis and evaluation of sources techique?
Document-centric technique. Extraction from external documents like:
* Reference models
* System requirements from professional publications
