Virtual Workbenches

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Virtual Workbenches

• Richard Anthony
• The University of Greenwich
• R.J.Anthony_at_gre.ac.uk
• http//www.BillericayDickie.com

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Overview Three virtual workbenches facilitate
practical experimentation and simulation of
technical and dynamic aspects of the computer
science curriculum.
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Design method / philosophy Dont water down
difficult aspects of courses ? instead, find
better ways to teach these aspects! Ways to
simulate / demonstrate / emulate are devised to
facilitate understanding by capturing the dynamic
behaviour of systems. Design is focussed on
clear presentation of technical / dynamic
concepts, ensuring that the user interface
is highly intuitive, enabling full user
configuration control, providing clear
instrumentation and instant feedback,
facilitating a wide range of progressive
experimentation, keeping the general
look-and-feel consistent.
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Mature, yet still growing Progressively
developed since 2002.
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Versatile Teaching and Learning
The workbenches can be used in many ways
lectures and tutorials, laboratory tasks,
coursework, unsupervised learning (structured -
with the student activities provided, or
unstructured - free experimentation).
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Integrated Environments
Each workbench focuses on a particular discipline
within computer science. Dynamic aspects of
systems are brought to life through
user-configurable, repeatable, simulations and
experiments. No programming required.
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Engaging Activities
Student activity guides provide progressive
challenges and encourage evaluation and
reflection.
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Evaluation

• Used by an increasing number of lecturers since
  2002.
• Evaluation in the form of
• Feedback via student critique in coursework,
• Student and staff responses to questionnaires,
• Personal teaching experience,
• Requests for modifications and additional
  features.

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Lab Activity example Real-Time Scheduling
Introductory DL 2 Fairness between two
processes 1. Configure the simulation as
follows Process 1 Task inter-arrival time 33
milliseconds, Computation time 16. Process 2
Task inter-arrival time 20 milliseconds,
Computation time 10. Scheduler Configuration
Deadline. 2. Press the Free Run button and pay
attention to the dynamic graph in the
Runtime State Display window. 3. When the
timestep reaches about 100, press the pause
button. Note the System Statistics and
Runtime Statistics. Questions Q1. Do the tasks
always seem to meet their deadlines? Q2. Do you
think the Deadline algorithm is fair to both
processes ? (In the context of real-time
scheduling, how do you interpret the term fair
?). Q3. Can the amount of CPU Idle time be
determined from the configuration of the
processes, or is a simulation experiment needed
in each case ?
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Summary Key Features Replacement of static
representations with dynamic, interactive,
user-configured simulations (showing how
components interact and also the temporal
relationships within those interactions). Student
s learn at their own pace, with repeatable
experiments. The tools can be used at any
location / time. Works on a laptop - no network
connection needed. The tools can be used in
lectures and tutorials to demonstrate concepts
as well as in the laboratory and unsupervised.
Progressive laboratory exercises designed to
encourage analysis and critical thinking. In
house ? Custom material, No licences.
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• Observations and Lessons learnt
• Do not underestimate the time needed to develop
  e-learning materials.
• (the single biggest problem, far more significant
  than technical hurdles,
• in my case certainly).
• An incremental approach is encouraged
• Enables early pay-back with some working
  functionality, whilst
• allowing reflection before the next phase.
• Promotes continuity, rather than inefficient
  stop-start fragmented effort.
• So design for extensibility and easy upgrade
• (Workbenches developed over a period of 5 years,
  but used 6 months in).
• The development of the tools is a form of CPD, in
  terms of developing
• teaching materials and also in actual software
  design and development.