Cube Voyagers Public Transport Module - PowerPoint PPT Presentation

1 / 28
About This Presentation
Title:

Cube Voyagers Public Transport Module

Description:

Information about multiple PT operators and their operating/fare policies ... FAREA/P(Mode) Skims Actual/Perceived Fares in Monetary units ... – PowerPoint PPT presentation

Number of Views:84
Avg rating:3.0/5.0
Slides: 29
Provided by: Matthew497
Category:

less

Transcript and Presenter's Notes

Title: Cube Voyagers Public Transport Module


1
Cube VoyagersPublic TransportModule
2
PTs Design Overview
  • Provides a multi-user-class, multi-routing
    transit algorithm which
  • Represents all the complexities of the public
    transport system
  • Uses efficient techniques to determine what
    different traveler's would consider to be
    reasonable public transport routes.
  • Allocates the demand between the various routes
    in a way similar to how travelers actually chose
    their routes

3
Represents Complexity of PT Systems
  • The route, where it stops (boarding and
    alighting both, only boarding, only alighting),
    and its variations (sub-routes) by period of the
    day. Details such as boarding delays at selected
    stops..
  • The type of vehicle providing the service (bus,
    light rail, heavy rail, ferryetc.) and its
    capacity (seated and crush). (capacity restraint
    is provided in PT)
  • Information about multiple PT operators and their
    operating/fare policies
  • Full representation of circular routes
  • Uses function of roadway speed, set travel times
    via time points, used fixed time.

4
PT Methodology
  • Compiles Data and Simplifies Network (Produces
    NET file)
  • Enumerates Acceptable Discrete Routes for every
    I-J (RTE file)
  • Finds least cost route
  • Enumerates all other routes within defined limits
  • Evaluates Routes and Performs Analysis
  • Decisions on access and assignment to individual
    lines through a series of logit choice models.
  • Route evaluation through a hierarchical logit
    choice model.

5
PT Steps
  • Enumeration finds a traveler's reasonable public
    transport routes from origin to destination
  • Identifies full discrete routes
  • The route should move progressively from the
    origin to the destination
  • Travelers tend to select journeys that are
    simpler that are direct or involve few
    interchanges
  • Travelers are unwilling to walk very long
    distances
  • These principals are used to constrain the
    potentially huge computational task of
    identifying all reasonable routes
  • The process can be considered analogous to a
    traveler using a map to reject routes which are
    very long relative to more direct alternatives
  • Creates a dataset of the reasonable routes
    between each origin and destination by user class

6
PT Steps
  • Evaluation qualitatively judges the routes
    calculated in the route enumeration stage of PT
  • The elements that can be used in this process
  • Limit on the number of transfers
  • The difference (actual percentage) difference
    between the minimum cost route and the evaluated
    route
  • Limit on non-transit cost (walk/drive access)
  • Limit on waiting and transfer times
  • Limit on In-vehicle costs
  • Specified by user class or market segment
  • Provides attractive and reasonable routes along
    with their probability of being used and the
    costs of each of the routes.
  • Calculates the probability of using each path
    using choice models at each decision point

7
Route Choice Probability
Note you can visualize route choice percent
allocations to calibrate model parameters to
known or expected routing patterns (i.e. not
only does the skim make sense but does the
multi-path routing make sense)
8
Tools to Build and Maintain a PT Model
  • Networks
  • PT System Data
  • Access Links (Automatic and/or Manual Coding)
  • Fare Systems
  • Multiple User Classes
  • Transfer Rules
  • Wait curves
  • Crowding
  • Skims (Cost Time)

9
Building Maintaining PT Networks
  • Ability to create and edit PT Lines in Cube
    Graphics
  • Ability to create and edit PT lines in Cube GIS
    with PT transit data stored in geodatabase
  • Ability to open multiple PT line files at once
  • AUTOMATIC UPDATES to PT lines to confirm to
    Highway Network edits
  • Tools to copy and reverse PT lines
  • Transit Line Manager for easier management

10
Transit Line Manager
11
PT System Data- Vehicle Characteristics
  • Public Transport Fleets are grouped by
  • Mode
  • Operator
  • Vehicle Type
  • Vehicles are given perceived time factors to
    designate desirableness.
  • Vehicles are given seated and crush capacities.
  • Capacity curves are defined to establish
    penalties based on the volume to capacity ratio.
  • Vehicle travel-times may be obtained from
  • Factoring congested roadway speeds
  • Speed variables in the network
  • Route schedule time-tables

12
PT System Data Manager
13
Multiple User-Classes
  • Each user-class may have unique factors which
    determine
  • Which routes are reasonable
  • How much walking?
  • How many transfers?
  • What are the access characteristics?
  • What is the maximum cost?
  • What is the maximum travel time?
  • Which routes are desirable
  • What is the perceived time for walking,
    transferring, waiting, riding (by mode)?
  • Are there rebates or special fare systems?
  • What is the sensitivity to crowding/capacity
    restraint?
  • What is the value of time?
  • What is the willingness to pay?

14
User Class-Specific Factors
  • MUMEXTRACOST (search beyond minimum cost)
  • MUSTUSEMODE (a single or group)
  • REBESTPATHCOST (alternate methods)
  • RECOSTMAX (max cost considered)
  • REWAITMAX (caps wait times)
  • REWAITMIN (insures minimum wait time)
  • RUNFACTOR by mode
  • SERVICEMODEL (used in evaluation)
  • SPREADCONST (multipath enumeration only)
  • SPREADFACT (multipath enumeration only)
  • SPREADFUNC (multipath enumeration only)
  • VALUEOFTIME by mode
  • WAITFACTOR by node (safety, amenities, etc)
  • XFERCONST (mode to mode penalties)
  • XFERFACTOR (mode to mode penalties)
  • XFERPEN (can be negative)
  • XWAITCURVE by node
  • The FACTORS keywords are
  • ALPHA (relative weight of walk to rest of
    journey)
  • AONMAXFERS (controls route search with MAXFERS)
  • BESTPATHONLY
  • BRDPEN by mode
  • CHOICECUT (multipath only)
  • DELACCESSMODE (deletes access modes from paths)
  • DELEGRESSMODE (deletes egress modes from paths)
  • DELMODE (any modes out of path building)
  • EXTRAXFERS1 (controls route search with MAXFERS)
  • EXTRAXFERS2 (controls route search with MAXFERS)
  • FARESYSTEM (obvious)
  • FREQBYMODE (headways across modes or not)
  • IWAITCURVE by node
  • LAMBDAA (multipath only)
  • LAMBDAW (multipath only)
  • MAXFERS (maximum transfer cutoff)

15
Fare System Representation
  • All sorts of complex fare systems can be modeled
    by user class
  • FREE No cost incurred
  • FLAT One fixed cost per use
  • DISTANCE Possible boarding cost unit cost per
    distance or cost lookup table
  • FROMTO Fare zone matrix based on the start/end
    zones
  • COUNT Counts number of fare zones crossed, sum
    number of zones crossed
  • ACCUMULATE Each fare zone has a fare and when
    crossed adds to cost
  • HILOW Fare result of the highest and lowest fare
    zone number crossed
  • Simple TAZ-TAZ fare matrices

16
Access Link Procedures
  • Access and Transfer links can be input via
  • Automatic generation through analysis of the
    network
  • External file
  • Network attribute
  • Automatic generation of non-transit links
  • Walk access to the stops, time and distance may
    be calculated along the network or using straight
    line connections.
  • Automobile access to the stops are calculated
    along the network for kiss-and-ride or
    park-and-ride.
  • Code park-and-ride lots and specify contributing
    zones or set maximum travel times or distances.
  • Wait curves may be specified to calculate wait
    time for boarding and transferring. These may be
    unique by location, mode, or user-class
  • Automated process limits increased to 999
    access/egress/transfer links can be generated for
    any give node for each mode

17
Wait Curve Specification
Note you can visualize and implement up to 255
shapes of wait curves that can be applied by node
and further modified by waitfactor by mode
18
Crowding Model
  • Crowd modeling is an iterative process enabling
    the capacity of a Public Transport System to
    influence the travel times in the system and thus
    the routes found and their probability of use, as
    calculated during route evaluation.
  • Two types of crowding model may be used
  • Link travel time adjustment
  • Wait time adjustment

19
Ways to Implement the Crowding Model
  • Link travel time adjustment
  • The link travel time adjustment models passenger
    perceptions that travel time is more onerous when
    they have to stand (rather than sit), or when the
    vehicle is crowded. The adjustment is represented
    by a crowding factor, which is multiplied by
    in-vehicle time to give the perceived value of
    crowded in-vehicle time.
  • Wait time adjustment
  • In the context of a transit leg from a boarding
    point to an alighting point with several lines
    operating, demand (without crowding) is allocated
    using the service frequency model (SFM), or
    service frequency cost model (SFCM). The wait
    time adjustment redistributes the initial SFM or
    SFCM loadings whenever any line does not have the
    available capacity to take its allocated demand.
    This excess demand is reallocated to other lines
    which have spare unused capacity, and incurs
    additional wait time.
  • The additional wait time (due to not being able
    to take the first service) may make this route
    less attractive, and so cause diversion of demand
    to other enumerated routes for the
    origin-destination pair.

20
Skimming the PT Network (SKIMIJ)
  • Available Skims
  • COMPCOST Skims Composite Costs
  • ValOfChoice Skims Value of Choice
  • IWAITA/P Skims Initial Wait Times
    Actual/Perceived
  • XWAITA/P Skims Transfer Wait Times
    Actual/Perceived
  • CWDWAITA/P Skims Crowding Wait Times
    Actual/Perceived
  • TIMEA/P(Mode) Skims Travel Time Actual/Perceived
  • CWDCOSTP Skims Crowding Link Travel Times
    Perceived
  • BRDPEN(Mode) Skims Boarding Penalty Perceived
  • XFERPENA/P(Mode) Skims Transfer Penalty
    Actual/Perceived
  • DIST(Mode) Skims Distance
  • BRDINGS(Mode) Skims Number of Boardings
  • BESTJRNY Skims Best Journey Times
  • FAREA/P(Mode) Skims Actual/Perceived Fares in
    Monetary units
  • EXCESSDEMAND Skims Excess Demand in Crowding
    Model
  • EXCESSPROP Skims Excess Proportion in Crowding
    Model

21
Report and Visualize PT Results Inputs
  • Reports
  • Graphics
  • Record Processing

22
PT Assignment Line Report
Note you can get summaries for totals or by
user-class for up to 10 user classes at a time
sorted by mode, operator or line name
23
PT Assignment Graphics
On, Off and Through
Line Profile
24
Advanced Analysis Techniques
  • Select Link Analysis
  • OD Matrix Estimation

25
Select Link Analysis
  • Allows the user to generate matrices of trips
    which satisfy a certain condition.
  • Optionally the selected trips may be assigned to
    the network for further analysis and
    visualization.
  • Selections may be any combination or exclusion
    of
  • Traversed Links and/or Nodes
  • Lines
  • Modes
  • Operators

26
Examples of Select Link Queries
  • The general form of the select link function is
  • SELECTLINK (expression)
  • MW1 SELECTLINK(L1023-1027)
  • MW3 SELECTLINK(L101-102, 104-105, 107-109)
  • MW1 SELECTLINK(LINERED1)
  • MW2 SELECTLINK(LINEA, B)
  • MW5 SELECTLINK(MODE3,5,7-9)
  • MW7 SELECTLINK(OPERATOR3)
  • MW2 SELECTLINK((L101-102 LINERED)
    (L201-202 LINEBLACK))
  • For conditions using node selection (that is, N
    conditions) the TYPE keyword can take the
    following values
  • THRU, to consider transit legs passing through
    the node
  • BOARD to consider transit legs boarded at the
    node
  • ALIGHT to consider transit legs alighted from at
    the node
  • NTTHRU to consider nontransit legs passing
    through the node
  • e.g. MW2 SELECTLINK((N123 TYPEALIGHT)
    (N123 TYPEBOARD))

27
Demand Analysis
  • The select process returns the demand for an I-J
    pair which satisfies a selection criterion.
  • The proportion of demand meeting the criterion
    may be obtained by including the keyword
    PROBABILITYT in the expression. In a similar
    manner percentages may be obtained by using the
    keyword setting PERCENTT.
  • e.g. MW3 SELECTLINK(LINETRAM1, PERCENTT)
    returns percentage values for each I-J pair which
    use the line TRAM1.
  • The select link process may load the portion of
    total demand meeting a select link criterion,
    rather than loading the entire demand as
    specified by the PARAMETER TRIPSIJ.
  • This is invoked by including the keyword and
    setting LOADT in the select link expression
  • e.g. MW2 SELECTLINK(L303-307, LOADT)

28
OD Matrix Estimation
  • Cube Analyst can perform matrix estimation on the
    in conjunction with the PT Module.
  • The process takes as Input
  • Initial Matrix
  • Partial Matrices
  • Trip Ends
  • Link Counts
  • Line Counts
  • Transit Line Ons/Offs/Throughs
  • All Input observations are given a level of
    confidence. This allows data from different
    sources to be properly considered and weighted.
Write a Comment
User Comments (0)
About PowerShow.com