Transcript Optimization and Simulation Approaches to Problems in

Line capacity estimation, timetabling and
other applications of simulation and
optimization tools for railway operations
planning
Narayan Rangaraj
Sudhir Sinha
Seema Ramteke
Industrial Engineering and Operations Research
IIT Bombay
Overview of planning
Strategic problems
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Capacity planning (infrastructure)
Tactical problems
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Timetabling
Fleet planning
Crew scheduling
Operational problems
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Train control
Dynamic scheduling
Dynamic pricing (revenue management)
Strategic decisions (railways)
Current railway framework
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LRDSS (Railway Board), Railplan (MRVN), etc.
Our work
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Definition of capacity on railway section
Capturing congestion effects and broad
scheduling strategies
Medium term capacity investments in signalling
Trade off between throughput (number of trains)
handled and transit time (average)
Strategic decisions (railways)
Robust capacity: capacity in the presence of
failure
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Signaling failures modeled and impact on train
running quantified
Simulation used as a tool for analysis
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Line capacity studies done in Secunderabad-Kazipet
section as part of tool development for IRISET,
Secunderabad
Virar-Dahanu Road section as a test section for
automatic signaling on main line sections
Extensive studies on Central Railway main line and
harbour line sections on the suburban network in
Mumbai
Railways (capacity analysis)
Simulation for line capacity analysis
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Reliability vs. capacity
Studies on the suburban network for a given
corridor
Quantify the trade-off between achievable
headway and service measures (such as
punctuality and average delays suffered by
trains) under a given pattern of failure
Railways (capacity analysis)
Terminal capacity
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Capability of handling trains at terminals
Routing possibilities
Look-ahead period and a routing algorithm applied
on an appropriate time-space network
Representation of network from primitive structures
identified
In the suburban case, trade off established between
achievable headway and turnaround time at platforms (e.g.
in Mumbai CST station, shown that a headway of 3 minutes
achievable for an identified stream of trains, provided that
the turnaround time was less than about 4 mins and 20 secs.
Tactical decisions (Railways)
Timetabling
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Master chart preparation tool for railway planning
Java based graphical tool with cyclical schedule generation
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Mini-scheduler for conflict checking and minor
timetabling changes
Java based tool with interface-based verification of conflicts
and suggesting first feasible times for activities. Simple
algorithms for backward scheduling and combined constraint
satisfaction
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Scheduler for full-scale timetabling
Based on constraint satisfaction tool CHIP
Capable of full-scale timetable generation
Tactical decisions (Railways)
Rake linking
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Long distance trains
Coaching stock utilisation (integrated with
maintenance schedules at terminals)
Timetables as an input
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Suburban trains
Integrated with timetables
Maintenance schedules as an input
Tactical decisions (Railways)
Long distance rake linking
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DSS which allows views of a common database
of
1. Timetable - origin/destination and timings
2. Terminal maintenance line charts (pit lines and washing
lines - also considering constraints on line length and
time for maintenance)
3. Rake link table (constraints on length of run between
two maintenance points and rake compatibility)
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Typical patterns of rake linking (self linking,
interchange of day trains)
Trains introduced to take advantage of rake link
possibilities
Terminals changed to accommodate rake links
Tactical decisions (Railways)
Suburban services rake linking
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Rake linking of timetabled suburban services is a single/
multi-commodity flow problem
Model helps in
1. finding minimum number of rakes for a given
schedule (big improvement NOT expected, as
timetables are generated with rake links in
mind)
2. capturing extent of empty running
3. generate/suggest changes in operating
parameters (e.g. turnaround times for a few
services) so that a rake can be saved
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Open problem : multi-commodity problem (e.g. 9 car/12 car
rakes, DC rakes/AC-DC rakes)
Other tactical decisions
Railways: Crew scheduling
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Initial system being developed
Bus system (urban): Depot allocation
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Variants of the transportation problem in network flows
Bus system (urban): Crew scheduling
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Multi-stage heuristics
1. (e.g. HASTUS) LP for the aggregate problem,
2. Variant of shortest path for individual work-piece definition
from a vehicle-route
3. (non-bipartite) matching for creation of work days
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Column generation
Marketing and Pricing models
Railways
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Network based models for pricing (based
on second shortest distance)
Marketing and service planning (Konkan
Railways)
Containers/Trucking
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Fleet utilization and locational imbalance
based pricing model
Other studies
Supply chain view of transport operations
Freight supply chains on Indian Railways
Containerised movement of import export
commodities to and from Jawaharlal Nehru
Port Trust to the hinterland
Summary of approaches
Large set of problems amenable to
analysis
Modeling and delimiting the scope of the
model calls for a lot of effort and
interaction with users
Major O.R. techniques used were
Simulation, Network Flow models and
Linear Programming, in many variants
Three examples
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Simulation studies on line capacity, including
an analysis of signal failures
A master-chart preparation tool with a
scheduling option
Rake linking for suburban services
Faculty/professional associates
Marketing applications/network based
pricing/Inland water transport - G. Raghuram
Simulation based tools - A.Ranade and K.
Moudgalya
Robust capacity – N. Hemachandra
Suburban rake linking, suburban timetabling,
network operations and pricing - M. Sohoni
Containerization - N. Viswanadham
Railway operations – A. K. Srivastava and
Vasudeva Kamath
Students and research associates
Ashok Kumar
B. N. Vishnu
Jugal Garg
Kapil Goswami
K. Chandrashekar
Mitali Johri
Prashant Puniya
Ravindra Gokhale
Rajesh Naik
Sadanand Kandalkar
Jai Mrug
Deepansh Malik
Sudhir Sinha
Vaishali Moharir
Mahesh Shenoy
B.C.S.Krishnamohan
J. R. Suresh
Hrishikesh Karmarkar
S. Chandran
Priya Mahadevan
V. Aneesh
Seema Ramteke
Amit Arora
Manish Garg
Publications and conference presentations in this area
N. Rangaraj and M. V. Kamath, "Dynamic operational policies for the Bombay
suburban rail transportation system", Journal of Transport Management,
vol20, no 2, 1996
N. Rangaraj and J. R. Suresh, "Decision support for crew scheduling in urban
transport", Journal of Transport Management, vol 18, no 3, March 1994
N. Rangaraj, G. Raghuram and M. V. Kamath, "Are passengers on Indian
Railways paying their way? Parts I and II", Railway Fare and Freight Committee
(Seminars and studies), Ministry of Railways, Govt of India,1993
Vishnu Narayanan and Narayan Rangaraj, "A network-based representation of
track layouts in railway stations", submitted to Transportation Research, Series
B
Narayan Rangaraj, Milind Sohoni, Prashant Puniya and Jugal Garg ,"Rake
Linking for Suburban Train Services", submitted to Opsearch
Narayan Rangaraj, "An analysis of cyclic timetables for suburban railway
services", submitted to Abhivyakti
Publications and conference presentations in this area
N.Rangaraj, A.Ranade, Moudgalya, C.Konda, M.Johri and R.Naik "Simulator for
Line Capacity Planning" Sixth Asia Pacific Operations Research Society, Delhi,
December 2003
N. Rangaraj and N. Viswanadham, "An example of a supply chain involving
multimodal containerised transport", National Conference on Transportation
Systems, Delhi, 2002
N. Rangaraj and A. K. Srivastava, "Some IT imperatives for Indian Railways in a
supply chain management environment", National Connectivity Vision: Surface
Transportation and Communication, Indian National Academy of Engineering,
Hyderabad, 2001
N. Rangaraj and A. K. Srivastava, "Network capacity planning and operational
control in Indian Railways", National Connectivity Vision: Surface
Transportation and Communication, Indian National Academy of Engineering,
Hyderabad, 2001
G. Raghuram, N.Rangaraj and M. V. Kamath, "Network based pricing for
passenger services on Indian Railways", Refereed Proceedings of the National
Conference on Transportation Systems and Studies, and Railway Fare and
Freight Committee (Seminars and studies), Ministry of Railways, Govt of India,
1993
Publications and conference presentations in this area
N. Rangaraj,"Quantitative models for capacity planning in transport systems,
ORSI Annual Convention, Ahmedabad, 2000
N. Rangaraj, M. Shenoy and M. V. Kamath, "Application of Constraint Logic
Programming to Commuter Train Timetabling", presented at the Australian
Workshop on Constraints, held in conjunction with the Australian Joint
Conference on Artificial Intelligence, Griffith University, Brisbane,Australia,
1998
N. Rangaraj, "Timetabling strategies for suburban railway operations", at IT
Tracks for IR (seminar organised jointly by IIT Bombay and Tata Unisys Ltd),
April 1996
N. Rangaraj and B. C. S. Krishnamohan, A systematic and quantitative view of
capacity estimation and enhancement of the Indian Railway network", ORSI
Annual Convention, Bhubhaneswar, 1993
N. Rangaraj and J. R. Suresh, "Crew Scheduling for urban bus operations",
ORSI Annual Convention, Ahmedabad, 1992
Narayan Rangaraj , "An analysis of Operations, Mode Choice, Pricing and
Network Economics of Container Movement", International Workshop on ITEnabled Manufacturing, Logistics and Supply Chain Management held in
Bangalore during December 15-16, 2003
Publications and conference presentations in this area
N. Rangaraj and B. N. Vishnu, "Node capacity and terminal management on
Indian Railways", Vision 2025, Railway Staff College, Vadodara, 2002
N. Rangaraj and M. Sohoni,"Meeting transport demands on a network: costs of
loaded and empty movements and of waiting", Industrial Engineering and
Operations Research, IIT Bombay (2001), also technical report at The Logistics
Institute - Asia Pacific, National University of Singapore
N. Rangaraj and N.Viswanadham, "Multimodal containerised transport for
export and import through Western India - a supply chain perspective",
Industrial Engineering and Operations Research, IIT Bombay, 2001, also
technical report at The Logistics Institute - Asia Pacific, National University of
Singapore
N. Rangaraj,"A note on section scheduling", Industrial Engineering and
Operations Research, IIT Bombay, 1997
N. Rangaraj and J. Mrug, "A decision support system for rake linking and
related operational decisions", Industrial Engineering and Operations
Research, IIT Bombay, 1997
Publications and conference presentations in this area
N. Rangaraj and M. V. Kamath, "Demand-sensitive schedule generation for an
urban mass transportation system", Industrial Engineering and Operations
Research, IIT Bombay, 1995
Konkan Railway Corporation Limited [with B. Banerjee and G.
Raghuram],Vikalpa v. 25, no. 1 (2000).
Narayan Rangaraj, Sudhir Sinha, Ravindra Gokhale and Sadanand Kandalkar,
Capacity Enhancement of the Mumbai Suburban Railway System through
Signaling Improvements: A Simulation Based Approach, Manuscript in
preparation
Ravindra Gokhale, Narayan Rangaraj and N. Hemachandra, Railway Line
Capacity Evaluation under Influence of Signal Failures, using a Simulation
Based Approach, Manuscript in preparation