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PBW 654
Applied Statistics - I
Urban Operations Research
Fall 2015
Hossam Abdelgawad, PhD, P.Eng.
Assistant Professor, Public Works Dept.
Faculty of Engineering, Cairo University
Teaching Staff…
Instructor Hossam Abdelgawad Assistant Professor
Office: 3rd Floor, Architectural Building
Email: [email protected]
Office hours:
Mondays and Tuesdays by appointment
2
Course Mechanics… Lectures
Monday 12:00pm-3:00pm (3rd Floor, Arch Building, Dr. Hossam’s Office)
Evaluation
Problem Sets and Midterm 40%
Final Exam: 60%
Software
MS-Excel©
Programming
Text
Lecture Notes
Richard Larson and Amedeo Odoni, Urban Operations Research, 1981, Prentice Hall, (available at: http://web.mit.edu/urban_or_book/www/book/)
Course Material
Lectures, tutorials, problem sets, solutions, and (some) readings will be posted on a website / drop box link / email
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Course Management…
Lectures, tutorials, problem sets, solutions, and (some) readings will be posted on a website / drop box link
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Course Information…
Covers quantitative methods and
techniques for the analysis and modelling of
urban transportation and service systems
Emphasizes probabilistic and optimization
methods for designing efficient operations
for various transportation systems
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Course Outline… Unit I
Probabilistic Modelling and Poisson
Processes
What do you mean “it’s Random”?
Poisson Processes
Poisson Processes and Random Incidence
Functions of Random Variables
Unit II
Queuing Systems
Steady State and Little’s Law
M/M/1, M/M/m, M/M/∞, M/G/1
Deterministic Queuing
Unit III
Network Modelling and Facility
Location
Shortest Path Problem
Chinese Postman Problem, Travelling
Salesman Problem
Facility Location
Unit IV
Mathematical Programming and
Simulation Modelling
Linear and Integer Programming
Network Programming
Simulation Modelling
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Background and History Urban OR is not new
1736, the Seven Bridges of Königsberg is a historically notable problem in mathematics
1937, Merrill Flood of Columbia University stimulated serious interest in the “traveling salesman problem” (see Chapter 6) through his efforts to route school buses more efficiently
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Scope
This course deals with the application of OR (Operations Research) methods and techniques to the analysis and modelling of urban service systems
Urban Service Systems
Transportation systems Bus, subway, highway, sidewalk, etc.
Logistically-oriented service systems Bunched Up Buses
Door to door pickup and delivery services (mail delivery, garbage collection, school bus routing)
Emergency services (police, fire, ambulances)
Street maintenance services (snowplowing, street sweeping)
Services at fixed locations (libraries, clinics, community centres)
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Analysis and Modelling
Analysis and modelling are essential for the
deployment of
(i) new services or
(ii) enhancements of existing services.
Effective deployment requires (typically):
Operational planning (aka functional design)
Design the details of the service
Operational control
Determine the rules/strategies/etc. to control operations
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Analysis and Modelling
The “Systems Approach” is usually implemented to carry out operational planning and control
Define the problem
Identify objectives
Identify alternative options to achieve the objectives
Model each option and analyze the consequences
Compare the options and select the best
Examples
Buying a new laptop?
Building a new subway line?
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The Big Picture…
OR/MS Methods
Linear/Integer Programming
Network Programming
Project Scheduling
Inventory Models
Queuing Models
Simulation
Goal Programming
Dynamic Programming
Forecasting
Transport Operations
Strategic Network Design
Vehicle Routing
Transit Vehicle Scheduling
Transit Crew Scheduling
Transit Real-Time Control Operations
Traffic Flow Modelling
Traffic Lights Operations
Runway and Air Traffic Operations
Airline Crew Scheduling
…
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OR Methods of this course
Probabilistic modelling
most urban services face uncertainties related to time of occurrence, type, location, and quantity of demands.
required to analyze non-deterministic behavior of the systems
Queuing theory
required to analyze congestion effects caused by the interaction between demand and supply of service
Network (or Graph) theory
required in the overall analysis of transportation networks and related routing problems, network design problems and location problems
Linear Programming
Used to find optimal solutions to a wide variety of problems
Simulation
may be necessary when analytical techniques fail 13
Approach… Develop understanding of transport operations
Demonstrate how to develop, solve and interpret
the results of probabilistic models applied to transport operations
Develop decision and policy making aids for large-scale, complex transportation systems
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Main Topics… Random Variables and Probability Distributions
Pedestrian Crossing Problem,
Little’s Laws for Queuing Systems,
Birth-and-Death phenomenon of queuing
processes,
Facility Location Problems,
Routing and Network Analysis,
Mathematical Programming and Simulation
Modelling
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Probability Modelling (Unit I)
Types of Random Variables
Discrete Random Variables
Continuous Random Variables
Relationships between Random Variables
Independent
Mutual Exclusive
Often used Probability Distributions
Probability Mass Functions for Discrete RV
Probability Density Functions for Continous RV
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Poisson Processes (Unit I)
Postulates of the Poisson Process
Properties of the Poisson Process
Random Incidence Process
Pedestrian Crossing Problem
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Queueing Process and Queueing
System… (Unit II)
Source
of users/
customers
C C C C C C
Queue
C
C
C
C
C
C
C
Servers
Size of
user source
Arrivals
process
Queue discipline and
Queue capacity
Service process Number of servers
Arrival point
at the system
Departure point
from the system
Queueing System
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What is a queuing system?
“Steady state” measures and Little’s Laws
Birth-and-Death Queuing Systems
Various Queueing System Configurations
M/M/1
M/M/m
M/G/1
Queuing systems with finite queue capacity -- “turning customers away”
Queuing systems with priorities
Deterministic Queuing Systems
Queueing Process and Queueing
System… (Unit II)
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Chicago
Dallas
Cleveland Kansas City
Atlanta Los Angeles
Boston
Network Modelling and Facility
Location (Unit III)
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Network Modelling and Facility
Location (Unit III)
Shortest Path Problem
Chinese Postman Problem
Travel Salesman Problem
Facility Location
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Time - Space Network
Representation
Cleveland
Chicago
Kansas City
Atlanta
Dallas
Los Angeles
Boston
Mon Tue Thu Wed Mon Fri Sun Sat
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Mathematical Programming –
Linear Programming (Unit IV)
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