Applying System Dynamics Principles to CDEEP System MTP Presentation Rohit Gujrati 08305002 Guide: Co-Guide: Prof Sahana Murthy Prof. Sridhar Iyer CDEEP IIT Bombay CSE,IIT Bombay

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Applying System Dynamics Principles to CDEEP
SystemMTP Presentation Rohit Gujrati
08305002Guide Co-Guide Prof Sahana
Murthy Prof. Sridhar IyerCDEEP IIT Bombay
CSE,IIT Bombay
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Outline

• Introduction
• Problem Definition
• System Dynamics Basics
• CDEEP Current State of the art
• CDEEP Model
• Features of a System Dynamics Model
• Conclusion Future Work
• References

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Introduction

• India produced 401,791 engineers in 2003-04 and
  in 2004-05, the number of engineering graduates
  increased to 464,743 1.
• But only 25 per cent of them are employable1.
• Main Reason lack of well qualified teachers
• Possible Solution
• Make IIT education accessible through Distance
  Education
• Cost Effective
• Global Reach

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Introduction continued

• IITB has been running the distance education
  program since last 10 years.
• Currently in the form of CDEEP to provide
• Good quality courses taught by IIT Bombay faculty
• To everyone
• At any place
• Both synchronous and asynchronous modes
• But number of students benefiting from CDEEP live
  courses has not increased as expected

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Problem Definition

• To model and analyse CDEEP system
• To find out
• If there is any bottleneck resource
• WhatIf analysis
• If any policy changes needed
• using System Dynamics
• Why???

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System Dynamics Basics

• Computer simulation modeling for studying and
  managing complex feedback systems, such as
  business, engineering, and social systems
• Think in terms of cause-and-effect
• Focus on Feedback Loops
• situation when output from an event will
  influence the same event in the future

More
More
More
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SD Modeling Standard approach 2

• Identify the problem
• Develop a dynamic hypothesis
• Create a basic causal loop diagram
• Convert the causal diagram to a Stock flow
  diagram
• Write the equations
• Estimate the parameters and initial conditions.
• using statistical methods, expert opinion, market
  research data or other relevant sources.
• Simulate the model and analyze results

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Causal Loop Diagram

• shows how one variable affects another.
• nodes represent variables and arrows (called
  causal links) represent relationship
• difficult to infer the behavior of a system only
  from its casual-loop representation

Node
Feedback Loop
Causal Link
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Stock and Flow Diagram

• Distinguishes between different types of
  variables
• Consists of three different types of elements
  stocks, flows, and information

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Stock and Flow Diagram cntd.

• SFD allows to represent relations among variables
  in terms of equations.
• For Example
• It becomes infeasible to solve as stocks and
  flows increase
• Use computer simulators
• Many simulators are available, (none is open
  source )
• We used Vensim PLE by Ventana Systems, Inc. 4
• Simulation result is time-history of variables
• in terms of Graph/Table

Population Initial(Population) ? (birth-death)dt
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CDEEP Current State of the art

• Distance Education through
• Live Webcast and Satellite Transmission
• Dynamic System with Feedback Loops
• 4 studios for live webcast (only 1 for satellite
  )
• Live Webcast through Internet at 100 kbps for
  each connection
• Not many students participating in this program

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Our Work

• Modeled Webcast and EDUSAT parts independently
• Applied iterative approach to develop the model

Variable Units Initial value/ assumption
Total number of Students Students 20
Number of courses courses 20
Quality of video dimensionless between 0 and 1
Total available bandwidth Kbps 8 Mbps
Bandwidth per connection Kbps/student Ideally 100 kbps
Student satisfaction dimensionless between 0 and 1
Server Performance dimensionless between 0 and 1
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Initial Webcast Model

• Causal Loop Diagram

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Initial Webcast Model

• Stock and Flow Diagram

joining new students
Students Leaving
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Simulation Results
Bottleneck
Equilibrium
Consistently 1
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Observations

• Number of Students becomes constant (200
  student) after 24 months
• Increasing number of courses doesnt help
• Bandwidth is the only bottleneck
• Server is always underutilized
• Limitations
• MHRD grants can be used to bring in more
  resources, e.g. Bandwidth
• Student feedback does matter
• Marketing issues can not be ignored

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Modified Webcast Model

• Causal Loop Diagram

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Modified Webcast Model

• Stock and Flow Diagram

Becomes 1 Gbps after 24 months
From 4 to 6
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Simulation Results
Server Overloaded
Huge increment due to increase in BW

• One more here

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Observations

• Grants can be spent for different resources
• Bandwidth increase much needed
• If bandwidth is increased, server will become
  overloaded after 3 semesters
• No. of courses limited by no. of studios
• Marketing issues are very important
• Feedback from students will influence no. of
  courses
• Similarity of syllabus with other universities
  affects inflow

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EDUSAT Model

• Transmission through EDUSAT satellite
• Dedicated 1 Mbps uplink and 500 kbps downlink
• Student Interactive Terminals (SIT) for reception
• Currently 72 Remote Centre (RCs), mostly
  engineering colleges
• RC coordinators and Instructors to ensure proper
  functioning

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EDUSAT Model
Causal Loop Diagram
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EDUSAT Model
Stock and Flow Diagram
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Results

• Effect of relevance of courses

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Results

• Optimal 20 courses and 0.7 marketing will reach
  373

Number of courses vs. number of students
Marketing vs. number of students after 18
months
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Results

• Effect of Distribution of Incoming Grants
• Optimal mix 20 courses and 0.7 on marketing

Grants Enter Here
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Observations

• Attention needs to be paid on publicizing CDEEP
  programs and encouraging student to join CDEEP
• Effect of grants visible after 12 months
• Optimal mix 20 courses and 0.7 marketing efforts

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SDModel Features

• Current simulators are all proprietary
  applications
• very limited collaboration among them
• No truly successful open source System Dynamics
  model builder currently available.
• Studied SystemDynamics Simulator8
• Huge code without proper documentation
• Prepared a higher level flowchart of a model and
  its constituent model components.
• Referred an initiative SD Info Model9

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System Dynamics Model
Dark line shows containment
Dotted line shows information flow
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Conclusion

• System Dynamics proved to be an important tool
  for modeling CDEEP system
• Models were verified by CDEEP staff
• Results obtained may help in improvement of
  existing system

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Future work

• Recommendations made may be validated by
  implementing them over the actual CDEEP system

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Publication

• Poster titled Using System Dynamics to Model and
  Analyze a Distance Education Program accepted in
  International Conference on Information and
  Communication Technologies and Development (ICTD)
  2010.

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References

• 1 McKansey Global Institute. Report on
  Emerging global labour market,2005.
• 2 John Morecroft, Strategic modeling and
  business dynamics a feedback systems approach ,
  Page no. 106
• 3 Deepak B. Phatak Kannan M. Moudgalya and R.
  K. Shevgaonkar. Engineering education for
  everyone A distance education experiment at IIT
  Bombay. Frontiers in Education, 2008.
• 4 System Dynamics Modelling, A Practical
  Approach, Chapman Hall, 1996.
• 5 http//www.cdeep.iitb.ac.in/
• 6 http//www.vensim.com/
• 7 http//www.public.asu.edu/kirkwood/sysdyn
• 8 http//sourceforge.net/projects/system-dynam
  ics
• 9 http//sourceforge.net/projects/sdinfomodel

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Thank You
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Appendix1 EDUSAT Model
Variable Equation/Initial Value
Number of students INTEG (inflow-outflow, 100)
Inflow DELAY FIXED( (Average student satisfaction Number of RCsNumber of transmitted coursesQuality of Transmitted Video) /15, 2, 50 )
Outflow (1-Average student satisfaction)(1-Quality of Transmitted Video)Number of students/10
Marketing about CDEEP programme IF THEN ELSE(Grants from MHRDgt0, 0.7 , 0.2 )
Relevance with other university syllabus 0.8
Quality of Transmitted Video Equipment Condition at RC
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Appendix2 EDUSAT Model
Variable Equation/Initial Value
Number of RCs DELAY FIXED( RC Instructor's MotivationMarketing about CDEEP programme600,12, 25 )
Equipment Condition at RC IF THEN ELSE(Support staff for Equipment Maintenancegt10, 0.8, 0.5 )
Incentives for RC Instructor 0.5
Grants from MHRD STEP(1e08, 24 )
Number of transmitted courses IF THEN ELSE(Number of studios11gt10Feedback from students/52RC Instructor's Motivation, INTEGER (Number of studios6Feedback from students/10) , Number of studios 11)