TDT4252 Modelling of Information Systems Advanced Course

1. TDT4252Modelling of Information SystemsAdvanced Course Sobah Abbas Petersen Adjunct Associate Professor, NTNU Researcher, Sintef sap@idi.ntnu.no Lecture 1: Introduction

2. Learning Goals (from Study Plan) • Theoretical insights into different modeling perspectives, languages and techniques for creating models of : • Information systems • Enterprises • Practical skills in • Analysing situations for modelling • Creating good models • The course will introduce the ideas of Enterprise Modelling and provide a holistic view of modelling. Lecture 1: Introduction

3. Background • Lecturer: • Sobah Abbas Petersen (IDI/Sintef)sap@idi.ntnu.no • Teaching Assistant: • Mohamed Asifmuhammad.asif@idi.ntnu.no • Students (Questionnaire to be filled out, available from the Lecture Schedule page) • Study program • Earlier courses • Modelling experience • Learning expectations Lecture 1: Introduction

4. This week • Information about the course • Motivation • Why model? • Why take this course ? • Clarification of the scope of the course • Historical Perspective on Modelling for Information Systems • NB. The lectures will be conducted in English. • Please feel free to ask questions in Norwegian or English. Lecture 1: Introduction

5. Course Outline • The course will consist of the following: • Perspectives of modelling and different modelling approaches and languages. • Enterprise Modelling and Active Knowledge Modelling (AKM) Approach • Enterprise Architectures • Assignments • There will be one mandatory assignment • Evaluation • A written exam – 75% • Assignment – 25% Lecture 1: Introduction

6. Practical Information • Course times: • Lectures • Mondays 12:15 – 13:00hrs room MA21 • Fridays 12:15 - 14:00hrs room F4 • Note: Lecture times may change, but students will be informed ahead of time. • Exercises • Mondays 15:15 – 17:00hrs room F3 • Course material (articles and lecture presentations) available from: • Course homepage: http://www.idi.ntnu.no/emner/tdt4252/ • It’s Learning Lecture 1: Introduction

7. Practical Information: mailing list • There is a mailing list for the course. Please subscribe by sending an email to tdt4252-subscribe@idi.ntnu.no • Mailing list is tdt4252@idi.ntnu.no Lecture 1: Introduction

8. Curriculum • The course curriculum is based on a collection of articles. • Lectures and lecture notes are a part of the curriculum. • Articles are available from the course homepage: (Lecture Schedule and Reading List pages) • The exercises should be done using the software application Metis, version 5.2.2. Lecture 1: Introduction

9. Assignment • The mandatory assignment (worth 25% of the final grade) is built up of several modules. • The assignment should include several sub-models that are linked: • This requires several modelling exercises that can eventually be put together as one model. • This requires thinking holistic and information as multi-dimensional. • Important: this work is done throughout the semester, after each modelling approach is presented in the lectures. • Deadline to be announced. Lecture 1: Introduction

10. Lecture Plan(Note: will be updated shortly) Lecture 1: Introduction

11. Terminology • Information systems: • “An information system is made of all the pieces of data and information used/stored/processed for the needs of the users and applications of enterprises” (Vernadat 1996). • Model: • A model is anything used in any way to represent anything else. It can be a physical object, a mathematical or logical representation, a conceptualisation of something. • It is more abstract, usually less comprehensive, and normally cheaper to create than what it models. • It is important to select which parts to represent as a model. • Conceptual Model: • A conceptual model represents 'concepts' (entities) and relationships between them. Lecture 1: Introduction

12. Terminology, contd. • Modelling Approach: • A modelling approachconsistsof a non-emptysetof semi-formal or formal languagesand a numberofrulesforusingtheselanguagestoconstructmodels. • Enterprise Model: • A consistent set of special purpose and complementary models describing the various facets of an enterprise to satisfy some purpose of some business users. • HolisticModel: • A modelthattakesintoaccountthedifferentaspects or viewsofthesituation or system modelled and howtheymayaffectoneanother. e.g. thefunctionalaspects, performanceaspects, userinterfaceaspects, etc. • ModelView • A specific aspect of a system or situation that is modelled, e.g. the functional view of the system. • The contents of the model viewed a from a particular perspective, e.g. the contents that a particular user is interested in. Lecture 1: Introduction

13. Motivation (1) • A model represents how people perceive an area or a domain. • Enterprises and IS development are ready for modeling tasks. • It is important to understand the mechanisms that are in play when modeling (alone or in a large group of people). • Modeling is important for analysis and requirements specification: • Poor analysis and requirements specification work is frequently the reason for the problems with software development. Lecture 1: Introduction

14. Motivation (2) Who can benefit from this course? • Everyone involved with enterprise and information system development, especially those involved in what is traditionally termed the ‘early’ phases of IS development. • People working with choices and adaptations of development methodology, modeling language or modeling tool in an organization. • People working with the development of modeling environments. • People who want to do research on information systems modeling at an international level (e.g. in projects and master theses in the IS group, in the university or in the research sector). Lecture 1: Introduction

15. Why Model? • Modelling may be conducted for several reasons in a variety of situations by a variety of people. • The model created depends on the reason for modelling. • Two main perspectives for creating models are: • IS perspective. • Business or enterprise perspective. Lecture 1: Introduction

16. Why model? – IS Perspective • To design and develop IT applications. • Analyse scenarios and user needs for requirements specifications. • A model is more abstract and often cheaper than a program. • A model provides input to the programming process: • Requirements • Conceptual overview of the application. • Identify modules that can be bought or developed – decision making. • Division of the work according to the capabilities of the application to be developed. • Automation of the development process – Model-driven development. Lecture 1: Introduction

17. Why model? – Business or Enterprise Perspective • Analyse and understand a situation: • How is a situation perceived by the organisation? • Obtain an overview of the organisation: • Organisational structure. • Functions and responsibilities. • Links IT to organisation: • IT support for the various organisational functions. • Design IT to serve organisations. • Link Business Strategy to IT Strategy. • Develop IT strategy for the organisation. • Identify problems and loopholes. • Design new business processes. Lecture 1: Introduction

18. Business Strategy and ISBusiness objectives sets IT priorities! Requirements specifications Business requirements Drives the investment in IT IS Perspective Design & Implement In response to Enterprise Perspective Organisational Processes, Innovative products & services that delivers Deploy Lecture 1: Introduction

19. Purpose of the Model • Before creating a model, it is important to understand the purpose of modelling and the purpose that would be served by the model that is created. This determines: • The design and focus of the model. • The perspectives of the model. • The modelling language and approach selected. • The modelling application. • The presentation of the model to the users. Lecture 1: Introduction

20. Learning Goals revisited • Different modelling perspectives, analyses of situations, Enterprise Modelling. • This course aims to build on IS modelling from an IT perspective and examine the use of IT from an enterprise perspective. • Thus, we will examine other kinds of models, whose primary purpose is not to design or specify IT systems; rather identify the need for IT systems and the types of systems. • We will look at different types of models that can be created. Lecture 1: Introduction

21. Scope of the course • Different perspectives of modelling. • Different kinds of modelling • IS modelling: requirements, goals, actors • Process Modelling • Product Modelling • Active Knowledge Modelling • Enterprise Modelling • Enterprise Architectures • We will use practical examples of models. • We will look at how the different types of models relate to one another to create Enterprise Models and Enterprise Architectures. Lecture 1: Introduction

22. A Historical Perspective on Conceptual Modelling (Based on an article and presentation by Janis Bubenko jr., Royal Institute of Technology, Sweden. June 2005) Pensum: A01: Janis A. Bubenko jr: From Information Algebra to Enterprise Modelling and Ontologies – a Historical Perspective on Modelling for Information Systems in Conceptual Modelling in Information Systems Engineering. Krogstie, John; Opdahl, Andreas Lothe; Brinkkemper, Sjaak (Eds.) Lecture 1: Introduction

23. Conceptual Modelling • Definition: • represents 'concepts' (entities) and relationships between them. • May be used for enterprise models, problem analysis requirements and design specification. • Primarily diagrammatic (2-dimensional diagrams). • The languages used for modeling have a limited vocabulary. • The languages used are originally meant to be generally applicable (and not for a specific domain). Some exception e.g. using so-called domain specific modeling techniques. Lecture 1: Introduction

24. Focus of early attemps • What were modelled were data and operations on the data. • There was a focus on representing the domain in strict, formal, computer-independent terms. • Data were modelled using abstract concepts. Lecture 1: Introduction

25. Modelling during four+ decades • Extended scope • Standardisation efforts Participation and understanding 2005 The search for a common framework 90s Refinement, models and extensions Pioneering work concepts 80s 70s 60s Lecture 1: Introduction

26. Modelling during four+ decades Young & Kent, 1958, CODASYL, 1963, Langefors 1965 • Extended scope • Standardisation efforts Participation and understanding Database Models 2005 The search for a common framework 90s Refinement, models and extensions Pioneering work concepts 80s 70s 60s Lecture 1: Introduction

27. Young and Kent (1958)“Abstract Formulation of Data Processing Problems” • … a way of designing different alternative implementations • Information set/item • Defining relationship • Producing relationship • Conditions • Temporal aspects Lecture 1: Introduction

28. CODASYL Development Committee:An Information Algebra (1962) The goal of this work is to arrive at a proper structure for a machine-independent problem-defining language at the systems level of data processing. … It should help the information processing community to clarify, understand the fundamental and essential features of data processing considerations. …With current programming languages the problem definition is buried in the rigid structure of an algorithmic statement of the solution, and such a statement cannot readily be manipulated. Source: CACM, Vol.5, No. 4, April 1962, pp. 190 - 204 CODASYL: Conference on Data System Languages Lecture 1: Introduction

29. The Scandinavian School: Langefors • the infological realm: where data processing problems were expressed. • the datalogical realm: design and analysis of a information processing system. • the “elementary message” – the smallest element that could certain any meaning. e = <s, a, v, t> s system point a attribute v value t time Lecture 1: Introduction

30. Modelling during four+ decades ANSI/X3/SPARC, IFIP Workinggroups • Extended scope • Standardisation efforts Information System Models Participation and understanding Database Models 2005 The search for a common framework 90s Refinement, models and extensions Pioneering work concepts 80s 70s 60s Lecture 1: Introduction

31. The period 1970-80 ”refinement and extensions" • The 1975 ANSI/X3/SPARC (Standards Planning and Requirements Committee) report: the three schema approach • External • Conceptual • Internal • IFIP WG 2.6 series: "Modelling in Database Management Systems” (1974) • IFIP TC 8 on Information Systems (1976) Lecture 1: Introduction

32. ANSI/X3/SPARC, 1975 • The three-schema approach offers three types of schemas with schema techniques based on formal language descriptions: • External schema for user views • Conceptual schema integrates external schemata • Internal schema that defines physical storage structures User view Neutral view Computer view • The framework attempted to permit multiple data models to be used for external schemata. Lecture 1: Introduction

33. IFIP Working Groups • IFIP: International Federation for Information Processing, an umbrella organisation for national societies working in the field of information technology. • IFIP WG 2.6 series: "Modelling in Database Management Systems” (1974). • IFIP TC 8 on Information Systems (1976). Lecture 1: Introduction

34. Modelling during four+ decades Business rule modelling • Extended scope • Standardisation efforts Information System Models Participation and understanding Database Models 2005 The search for a common framework 90s Refinement, models and extensions Pioneering work concepts 80s Temporal aspects, Semantic Modelling 70s 60s Lecture 1: Introduction

35. Ambitions of the 80’s • To understand better and improve parts of existing methods and tools. • To harmonise different notions and methods. • To enhance the requirements capture and validation stage of the systems life-cycle. • To provide computerised assistance to the process of developing a specification. • To pay attention to human, cognitive, linguistic and social aspects of IS. Lecture 1: Introduction

36. Modelling research in the 80’s • Improving the expressive power of semantic data models (including abstraction mechanisms) and adding the temporal dimension. • ”semantic modelling” vs relational data modelling. • What are we modelling? The DB? The IS? The real world? • The operational vs. the deductive and temporal approach. Lecture 1: Introduction

37. Modelling during four+ decades Modelling of ”why”, Enterprise Models Business rule modelling • Extended scope • Standardisation efforts Information System Models Participation and understanding Database Models 2005 The search for a common framework 90s Refinement, models and extensions Pioneering work concepts Usereducation and participation, Userfocus, Organisationalchange 80s 70s 60s Lecture 1: Introduction

38. Modelling in the 90’s: focus onorganisational aspects,participation, and understanding … "the understanding and support of i) Human activities at all levels in an organisation. • Change, be it of the product, of the process or of the organisation. • Complex user organisations, and individual users" (ESPRIT 91) Lecture 1: Introduction

39. The 90’s: Widening the scope • Interoperable systems • Semantic heterogeneity • Non-functional requirements • Business modelling/engineering • Modelling of intentions and actors • Participative modelling • ”Method knowledge”* • ”Patterns” Lecture 1: Introduction

40. Modelling during four+ decades Modelling of ”why”, Enterprise Models Business rule modelling • Extended scope • Standardisation efforts Information System Models Participation and understanding Database Models 2005 The search for a common framework Domainspecific ”ontologicalmodels” and languages 90s Refinement, models and extensions Pioneering work concepts 80s Formality vs. informal 70s 60s Lecture 1: Introduction

41. Modelling during four+ decades ANSI/X3/SPARC, IFIP Workinggroups Modelling of ”why”, Enterprise Models Young & Kent, 1958, CODASYL, 1963, Langefors 1965 Business rule modelling • Extended scope • Standardisation efforts Information System Models Participation and understanding Database Models 2005 The search for a common framework Domainspecific ”ontologicalmodels” and languages 90s Refinement, models and extensions Pioneering work concepts 80s Usereducation and participation Formality vs. informal 70s Temporal aspects, Semantic Modelling 60s Lecture 1: Introduction

42. Current Trends • Enterprise Models • Active Knowledge Models • Model-Driven Development • Semantics, Ontologies • Interoperability and Standardisation • Leveraging on developments in other fields, e.g. • AI – reasoning about knowledge, knowledge representation, uncertain knowledge • Modelling work in other engineering fields Lecture 1: Introduction

43. Main elements of a modelling activity Lecture 1: Introduction

44. Enterprise Modelling • The purpose of modelling is not only IS design. • Models not only address “what?”, but also “why?”. • Integrates conceptual and process models of the business with objectives, actors, business rules and information system requirements. • Provides traceability from information system solutions to business objectives. • Improves the quality of modelling and the models by making it a “participatory” activity. Lecture 1: Introduction

45. Summary • Introduction to the course and practical information • Historical perspective of IS modelling over 4+ decades. Lecture 1: Introduction

46. Next Lecture • Monday, 17 January, 12:15 – 13:00hrs, room MA21 (Realfagbygg) • Topic: Why model? The Role of Models in organisations.Introduction to Modelling, using an example that illustrates the roles a model could play in an organisation and the value of it. Lecture 1: Introduction