A Systems Model for the Field of Informatics

1. A Systems Model for the Field of Informatics A. J. Cowling Department of Computer Science University of Sheffield

2. Structure of Presentation • Background • A model for the structure of the SE curriculum • General systems theory applied to Informatics • Hierarchical curriculum models • The Proposed Three-Dimensional Model • The products dimension • The process dimension • The people dimension • relationships with products and processes • Evaluation and Conclusions • Comparison with the Great Principles model • Conclusions. University of Sheffield Department of Computer Science

3. The SE Curriculum • A Multi-Dimensional Model • Three main dimensions: products, processes and people 1 • Products defined in terms of levels of abstraction of components 2 • Processes defined in terms of relationships to people: • individuals, groups and markets • Also introduced a further dimension: • balance of theory and practice. • Application to SE • Described its relationships with other disciplines: • Computer Engineering, Computer Science, Information Systems • A. J. Cowling, A Framework for Developing the SE Curriculum, Proc. International Workshop on SE Education, Sorrento, 1994, pp 111 – 118. • A. J. Cowling, A Multi-Dimensional Model of the SE Curriculum, Proc 11th CSEE&T, Atlanta, 1998, pp 44 – 55. University of Sheffield Department of Computer Science

4. General Systems Theory • The British Computer Society • The UK Professional Body for Information Systems Engineering; • Accredits degree programmes in this whole area: • viz Computer Science, Computer Engineering, Software Engineering, Information Systems, Information Technology, Artificial Intelligence, etc • Hence covers the whole of Informatics; • Accreditation criteria need to be applicable throughout. • The Artefacts Being Studied • For all programmes the products are information systems; • Different programmes focus on different aspects of these systems; • General Systems Theory is applicable to all of them; • It defines key aspects that must be covered in all programmes. University of Sheffield Department of Computer Science

5. Hierarchical Curriculum Models • Usual Structure • Curriculum for a discipline consists of knowledge areas; • Knowledge areas consist of knowledge units; • Knowledge units consist of topics; • Topics may have attributes: • core or optional, levels on Bloom’s taxonomy, etc. • Limitations • Different disciplines may need different views of the same knowledge area 3: • different structures of units, or emphases; • Within a discipline, relationships between different areas or units are not easily represented. 3. A. J. Cowling, Teaching Data Structures and Algorithms in a Software Engineering Degree: Some Experience with Java, Proc 14th CSEE&T, Charlotte, 2001, pp 247 – 257. University of Sheffield Department of Computer Science

6. Unifying These Approaches • Focus: Knowledge Structures and Relationships • Approach: A Three-Dimensional Model • Places Informatics knowledge areas in a space; • Key dimensions for this space: • Products, Processes and People • Each dimension has a hierarchical sub-structure: • For products, from general systems theory; • For processes, from activities and the information they use; • For people, from organisational structures. • Omission • The balance of theory and practice is not included as a dimension: • this would be desirable, to link theory to applications, • but the structure for such a dimension is not clear. University of Sheffield Department of Computer Science

7. The Products Dimension 1 • Hierarchical Structure • Root levels (nearest the origin) derived from core computing concepts; • Layered to match levels of abstraction; • Leaf levels derived from application domains of computing. • Aspects of the Levels • All levels relate to kinds of information systems; • Aspects of the root levels come from General Systems Theory: • systems are structured from sub-systems by some paradigm, • systems have a purpose (ie processing and storage of information), • systems have a boundary, across which they communicate, • internal sub-systems must communicate to achieve purpose; • Aspects of the leaf levels all involve different kinds of abstract software components interacting. University of Sheffield Department of Computer Science

8. Level of Abstraction Structuring Paradigm Processing Storage Internal Communication External Communication Analogue Circuits Modulation Gate circuits Feedback Analogue signals Analogue signals Digital Circuits Clocking Combinatoric logic Sequential logic Digital signals Physical layer protocols Digital Components Micro-programming Processors Memories Buses MAC layer protocols Computers Assembly language Interrupt handling, etc Virtual memory Device level I/O Link & network layer protocols OS Services Imperative programming Process management Filing systems Buffer management Transport layer protocols Programming Concepts Programming paradigms Translators, VMs Data typing Data streams Session layer protocols Programming Abstractions ADTs Procedures and methods Data structures GUIs, event streams Application layer protocols APIs Software components Software Architecture Design patterns Domain - specific abstractions The Products Dimension 2 University of Sheffield Department of Computer Science

9. Methodologies Process Models specify need Activities Sequencing Schedule & Work Breakdown Objectives & Constraints manipulate need Models Resources use Notations The Processes Dimension 1 • Two Structures for Processes • Abstract, in terms of sequences of activities that produce models; • Concrete, in terms of plans, resources and their control. University of Sheffield Department of Computer Science

10. Methodologies specify Processes need Activity Sequence Schedule & Work Breakdown Objectives & Constraints manipulate need allocate Models Resources use Notations The Processes Dimension 2 • Combining These Structures University of Sheffield Department of Computer Science

11. The People Dimension • Levels of Organisational Structure • The opposite way round to the usual organisational hierarchy; • root level (nearest the origin) – individuals, • middle levels – different sizes of teams, • outermost level – organisations or business units. • Structures Within Levels • Each level will have a variety of purposes; • These will lead to different application domains. • Roles of People • Reflected in relationships with product and process dimensions: • as users of products, • as developers working within processes. University of Sheffield Department of Computer Science

12. Combining the Dimensions • Forming a Knowledge Space • Any topic can therefore be located in the space by: • which abstraction level of products it refers to, • which aspect of systems theory it covers, or which application domain, • which abstraction level of processes it refers to, • what size group of people it relates to. • Example • Database normalisation (a topic in CS, CE, SE, IS and IT); • Irrespective of programme, this is concerned with: • the storage aspect of the software components level, • for domains involving information with an ER structure, • the design activity that involves manipulating ER models, • the business of the organisation requiring the database. University of Sheffield Department of Computer Science

13. The Great Principles Model 1 • Also Multi-Dimensional • Two main dimensions: principles and practice. • The Principles Dimension • Has two elements: mechanics and design; • Both focus on laws: for “what” and “how”. • Mechanics corresponds to the general properties of systems • cf the five windows: automation, coordination, computation, recollection (storage), and communication; • Design corresponds to how two elements are brought together: • the characteristic properties for specific products, and • the relationships between components that produce these. • The Practice Dimension • Identifies generic activities that underpin processes: • innovating, engineering, modelling, validation, programming, applying. University of Sheffield Department of Computer Science

14. The Great Principles Model 2 • Structuring The Space • Identifies two components: applications and core technologies. • Applications and Domains • Concerned with why people need computing; • Correspond to the application domains for products, and their relationships with people. • Core Technologies • Currently 30 of these: from algorithms to workflow; • Capture key common features of domains; • The principles and practices capture how this happens. • Correspond to areas within the knowledge space: • some mainly focus on lower level products (databases, compilers, networks, operating systems, etc), • others on kinds of applications (graphics, robots, vision, etc). University of Sheffield Department of Computer Science

15. Evaluation • Application of the Model to the Whole Field • All informatics disciplines involve products: • which are information systems, so general systems theory is applicable to them; • All informatics disciplines involve processes: • historically some have not given them much attention, but to prepare students adequately for careers they should! • maybe this part of the Great Principles model is weak; • All informatics disciplines involve people, either as users, developers or both. • Does the Model Cover The Whole Field? • The above suggests that it does; • The acid test will be mapping current curriculum models into it: • one example topic is not enough! University of Sheffield Department of Computer Science

16. Conclusions • A Model for the Whole Field of Informatics • The structure of the model has been defined; • It reflects fundamental principles: • eg the application of general systems theory to products; • Its structure allows it to capture relationships between topics: • in a more general fashion than conventional hierarchical curriculum models. • Restricted to Knowledge Structures • It does not capture the balance of theory and practice; • Hence, it ignores some distinctions between disciplines. • Future Work • To map existing curriculum models into this model: • ie to place actual topics in this space; • To include the balance of theory and practice. University of Sheffield Department of Computer Science

17. The End • Thanks for your attention!! • Any Questions? University of Sheffield Department of Computer Science