SWT Diagrammatics

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SWT - Diagrammatics

• Lecture 1/4 - Introduction to Diagrams
• 25-April-2000

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Introduction

• My name is Athanasios Tsintsifas, for short
  just Thanassis...
• I am a Ph.D. student and a member of the LTR
  department of the University of Nottingham.
• I have contributed in the development of
  CourseMaster and created the Daidalos system as
  part of my research.
• You can reach me at azt_at_cs.nott.ac.uk
• I have a page at http//www.cs.nott.ac.uk/az
  t
• Youll be able to find each lectures notes in
• www.cs.nott.ac.uk/azt/diagrammatics/index.html

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LTR

• Learning Technology Research (LTR)
• The LTR group is focusing its research in finding
  ways to facilitate teaching and enhance the
  learning experience.
• For the last three years, LTR has been developing
  the CourseMaster system.
• The Ceilidh system, the ancestor of CourseMaster,
  has been in use for over 10 years by more than
  100 universities in the world.

Diagrammatical Assessment
WWW Interface, Prolog
SQL
Pascal
Course Master CD-ROM
First version, C module
Ceilidh 2, C, C modules
SML
X-Interface, Software-Tools
Java
Z
1988
1990
1992
1999
1995
1998
2000
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Automatic Assessment Categories

• Two types of assessment
• Fixed response
• Multiple Choices,
• Questionnaires
• Free response
• Programming languages,
• Essays,
• Graphics,
• Diagramming
• The Ceilidh system has been assessing both fixed
  and free response coursework.
• With CourseMaster and Daidalos graphical and
  diagramming exercises can be assessed too!

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Problems that needed overcoming

• Graphics and Diagramming based exercise poses
  inherent problems to a system for automatic
  assessment
• Each domain needs its own
• graphical editor,
• assessement metrics
• Domain editors are complex to create.
• Generic editors are unable to retain extra
  information that is needed for diagrammatic
  assessment of coursework.
• The setting of an automatically assessed
  graphical exercise is a complex process that
  requires the cooperation of many users.

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The Approach
Daidalos
Ariadne
Theseus
CM servers
CM Clients
DATSYS system
CourseMaster system
Java platform
Operating Systems Windows 95, 98, NT, 2000,
Solaris, Linux
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The Approach

• DATsys is a Object Oriented Framework
  encapsulating the design of a family of
  diagramming editors.
• Daidalos, Ariadne and Theseus are composed with
  parts of the same framework.
• Daidalos provides facilities to design
  graphically domain component libraries.
• Ariadne provides facilities to automatically
  generate the student diagrammatic editor
  (Theseus) using Daidaloss libraries and the
  required marking specification.
• Theseus is used by the students in order to
  design their diagrams and can be generated
  independently for each exercise, unit or course.

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Daidalos
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A Generated Theseus
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What we will be covering

• There will be three more lectures on diagramming
  and three exercises in total
• (D1) Introduction to Diagrams,
• (D2) Diagrams in Sciences and CS - Logic
  Diagrams,
• (E1) Two logic circuit exercises
• (D3) Diagrams for Software Development
• (D4) OO Diagramming / UML / Meta-diagramming
• (E2) One OO design exercise

(D1)
(D2)
(E1)
(D3)
(D4)
(E2)
Tuesday 25/04
Thursday 27/04
Tuesday 02/05
Thursday 04/05
Friday 28/04
Friday 05/05
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What we will be covering

• First lecture
• Introduction - definitions
• A historical review
• Diagram advantages
• Diagram universal properties
• Diagram origins
• Important diagrammatic domains

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What we will be covering

• Second lecture
• Diagram Distinctions,
• Flowcharts, Nassi-Shneiderman Diagrams,
• Structure Diagrams, Dataflow Diagrams
• Software Level Charts, Cell-Arrow Diagrams
• State Transmission Diagrams, Petri Nets,
• Logic Gates, Logic Circuits, Venn Diagrams
• Entity-Relationship Diagrams

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What we will be covering

• Exercise week 1
• Exercise Lift This is a simple exercise, in
  which you'll have to design the logic circuit
  which will operate a lift using logic gates.
• Exercise NuclearThis is a more advanced
  exercise, in which you'll have to design the
  logic circuit which controls the launch of
  nuclear weapons (albeit a simplified one!)

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What we will be covering

• Third lecture
• OO Design Notations, Objects,
• Messages / Control Data Flow, Classes
• Class Attributes and Operations
• Visibility of Attributes and Operations
• Relationships Association, Multiplicity
• Relationships Aggregation
• Relationships Dependency
• Relationships Inheritance

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What we will be covering

• Fourth lecture
• UML diagramming
• Object diagrams with UML
• Class diagrams with UML
• OO Developments
• Meta-Diagramming
• Software Demonstrations
• How to Proceed / Further Information

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What we will be covering

• Exercise week 2
• Exercise hotel This is a simple exercise, in
  which you'll have to design (not implement) a
  class diagram for a hotel room booking system.
  You will be using a similar to UML notation.

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Dia-gramm(a),(h),(wn)to - line

• to convey a message by means of drawing lines.

Representation
More Arbitrary
More Homomorphic
TEXT
PICTURES
DIAGRAMS
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Diagram

• James Maxwell's definition (Encyclopedia
  Brittanica, 11th edition) a figure drawn in such
  a manner that the geometrical relations between
  the parts of the figure illustrate relations
  between other objects.

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Diagrams are

• In general, representations of things, thoughts
  and relationships that usually
• attempt to present information in a concise,
  clear and understandable way,
• try to convey information using a specific
  notation or not,
• can present non-visual information in a visual
  form,
• can depend on agreed conventions, like written
  text, but their overall form affects their
  interpretation.

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History of Diagrams

• The earliest abstract illustrations are maps.
• Maps relate physical distances between locations
  in the world and physical distances of these
  locations on paper.
• By their nature, they abstract out detail (e.g.
  roads are represented by straight lines,
  coastlines are abbreviated etc)
• The map is not the territory...?

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The History of Diagrams

• Geometric diagrams have been around for quite
  some time Manuscripts containing proofs with
  diagrams of the Pythagorean theorem exist from
  the time of ancient Greeks -These diagrams are
  also based on a concept of metric space.
• Descartes' invented the Cartesian coordinate
  system in the 17th century.
• Scientific discoveries in physics and chemistry
  resulted in increasingly abstract diagrams.

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The History of Diagrams

• Topological diagrams their history is difficult
  to trace.
• In the middle ages, hierarchies of trees were
  used to document lineage.
• Religion and cosmology of the middle ages made
  great use of diagrams, including graphs.
• In the Renaissance, the rediscovery of Greek
  thought resulted in many diagrams of
  philosophical and scientific nature - mostly
  for illustration purposes .

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The History of Diagrams

• In the 19th century, the work of Boole inspired
  the invention of Venn diagrams.
• Charles Peirce extended these and invented
  existential graphs
• The explosion of abstract mathematics resulted
  in the proliferation of tree and graph
  representations.

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A
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For some tasks diagramming works better
x

• SP(I,O) ? ?x?y delay(I, y) ? not(I, x) ?
  and(y, x, O) delay(I, O) ? ?t O(t1)
  I(t)
• not(I,O) ? ?t O(t) 1 - I(t)
• and(I1, I2, O) ? ?t O(t) I1(t) x I2 (t)
• Two representations that describe a configuration
  of the same single pulser.

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y
i
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Advantages of diagramming

• Many comparisons of verbal and visual tasks have
  shown that human capabilities differ in the way
  they are distributed through the brain
  different people choose different strategies to
  accomplish the same tasks.
• Although there appear to be differences between
  the strategies that individuals choose in visual
  reasoning tasks, strategy is also affected by
  education, expertise and culture.
• Furthermore, topological complexity of a diagram
  affects the performance of an individual.

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Advantages of diagramming

• Advocates of diagrams have suggested that the
  right hemisphere of the brain is "needlessly at
  rest and underutilised" when using text-only
  notation for descriptions.
• Research has also shown that some simple visual
  tasks can require more time when carried out by
  the left hemisphere.
• There are many tasks in which verbal and visual
  information is combined. Research has shown that
  memory improves when a concrete image can be
  associated with a task (e.g. for navigation
  purposes route memory depends on visual
  landmarks)

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Universal Properties

• However, even if many diagrams rely on expert
  knowledge, diagrams have many universal
  properties
• Adults from all cultures show quantity increasing
  from bottom to top of a page.
• Time direction is always from left to right.
• Everybody can be aware that an object is
  related to another object just by observing
  at the connectivity between the two it
  doesnt matter what kind of connection it is
  as long as the connection is described as a
  kind of a line.
• Any more universal properties?

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Diagrams are based on origins of

• Resemblance The most naive account (more likely
  to be made of diagrams with a strongly pictorial
  element) is simply that they resemble the things
  they refer to.
• Metaphor It is possible to depict things that do
  not exist physically, that we, humans, have a
  mental image of them (e.g. abstract concepts, or
  structure representations in computer systems)
• Concrete Descriptions By abstracting physical
  entities we can get a better picture of the world
  around us.

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Diagrams offer

• Locality and Labels Diagrams group related
  information in the same area, so searches can be
  constrained to the scope of a goal.
  Correspondences can also be established from
  topological relationships.
• Expressive Power and Specificity Diagrams allow
  multiple layer abstraction. They have fewer
  interpretations than unconstrained textual
  notations.
• Pragmatics Diagrams provide a vocabulary for
  discussing the way that notations are
  interpreted. Every notation highlights some kind
  of information and obscures other aspects in
  which we are not interested in at that moment.

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Diagram use

• Applied psychology uses diagrams as a way to
  learn about the nature of cognition, and analyses
  how different diagram types and diagram features
  affect human problem solving.
• Cognitive science the use of computer models
  allows researchers to propose and investigate
  systematic (and potentially formalisable) models
  of reasoning. Cognitive science is focused on
  definite descriptions of diagrammatic reasoning
  tasks and investigates how can these models
  accommodate analogue representations rather than
  symbolic logic ones.

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Diagram use

• Linguistics is also using in diagrams in their
  quest to analyse syntax, semantics, and
  pragmatics of spoken languages.
• Computational linguistics is using diagrams to
  depict information that enables research
  analogous to the research on verbal language e.g.
  formulation of grammars that allow automatic
  parsing and generation of diagrams.
• Visual programming promises to make programming
  accessible to more people via the use of diagrams.

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Diagram use

• Data visualisation as most diagrams are
  created by a person with a com- municative
  intent and an understanding of the
  expected reader, data visualisation diagrams
  help with the characterisation of data and
  formalisation of design rules in order to
  facilitate the user (e.g. in helping a
  programmer to write code).
• Graphic design uses diagrams in order to
  facilitate the task of a graphic designer to
  accept a given set of information, who can then
  prepare a way of communicating that information
  effectively.

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Diagram use

• Education uses diagrams in order to facilitate
  education and teaching in all subjects. Education
  is concerned with finding out which types of
  diagrams are appropriate for what teaching goals.
  Learning concepts diagrammatically can help to
  solidify abstract concepts.
• History and philosophy of science Scientific
  discovery has often been associated with novel
  uses of representations (such as algebra or
  Cartesian coordinates). Past discoveries have
  largely been founded on diagrams.

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Diagram use

• Architecture Architects spend much of their time
  working with visual representations, although
  their most common representation is the sketch.
  Diagrams support architectural problem solving
  and facilitate the creativity that architects
  experience when sketching
• Management - Brainstorming Mind mapping
  techniques use diagrams in order to categorise
  tasks, to help people remember better and to
  provide a visual path to the tasks that need to
  be performed.

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Diagram use

• computer science and engineering diagrams are
  used to great extent in order to facilitate
  information sharing, information filtering and
  understanding of complex notions.
• Biology Genetics

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Ribbon structure of MCAD monomer with C8-CoA
complex

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The end of lecture 1