The University of Maryland, Institute for Systems Research
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Integer Programming Models for Ground-Holding in Air Traffic Flow Management
A Ph.D. dissertation. Integer programming models are applied to two
problems in air traffic management: the
stochastic ground holding problem and the ground holding problem with banking constraints.
In the first problem, the stochastic nature of arrival capacity for an airport is modeled
by an integer program that provides the optimal trade-off between ground delay and airborne
delay. In the second problem, the desire of the airlines to keep the landings of banks of
flights temporally grouped is modeled via several different formulations of the ground
holding problem. Also, an overview of CDM and its operational paradigms is given.
A Comparison of Formulations for the Single-Airport
Ground Holding Problem with Banking Constraints
Authors: Hoffman, Ball
In this paper, five different models of the single-airport
ground holding problem with banking constraints (GHB) are constructed. The models are
evaluated both computationally and analytically. It is shown that for two of the models,
the banking constraints induce facets of the convex hull of
the set of integer solutions. In addition, a linear
transformation of variables and a branching technique are explored.
The Static Stochastic Ground Holding Problem with Aggregate Demands
Authors: Ball, Hoffman, Odoni, Rifkin.
Submitted to ORJournal.
A practical, real-time integer programming model is
developed to find the optimal trade-off between ground holding and airborne holding
in the planning of a ground delay program.
Collaborative Decision Making in Air Transportation
Authors: Hoffman, Hall, Ball, Odoni, Wambsganss.
Manuscript in preparation.
This paper describes the collaborative decision-making (CDM) initiative
being undertaken in the air transportation community. CDM's initial
focus was on shortcomings of ground delay programs used to regulate
traffic flow in the present air transportation system. This paper presents
the algorithms and paradigms employed by the CDM initiative to improve
the system. The paper also describes CDM efforts to improve several
important aspects of the present air transportation system, including
aircraft routing and arrival-departure resource allocation, and it
discusses convergence and quality of solution issues with respect to
Elementary Mathematical Models with
Authors: Hoffman, Previte.
Manuscript in preparation.
An undergraduate text on finite mathematics. Topics include
Finance, Linear Models, Probability, Counting Principles,
Data Analysis, Non-linear models and Logic.
- Title: Rolling Spike Analysis Report
Authors: Hoffman, Shisler, Howard, Klopfenstein, Ball.
This document relays the
findings of the "Rolling Spike" Task Force of the CDM
Analysis Subgroup that was formed to investigate the "rolling spike" phenomemon observed
in demand predictions for arrivals to airports throughout the country.
.doc format (Word 6.0)
- Title: What is IPE?
This document explains the IPE metric that is used by
NEXTOR and the CDM Analysis subgroup to measure the predictive accuracy
of flight events.
.doc format (Word 6.0)
- Title: IPE_results.v1
This document is the first in a series of reports on departure
time prediction accuracy. The numbers were generated by applying
the IPE metric to flight record updates (ADL files) for various days
at airports SFO, BOS and EWR.
.xls format (Excel 7.0)
- Title: Collaborative Decision Making in Air Traffic
Management: A Preliminary Assessmet
Authors: Ball, Hoffman
This document relays the findings of a 1998 study performed by
NEXTOR (The National Center for Excellence in Aviation
Operations Reserach). The study made a preliminary assessment
of the performance of the prototype operations of CDM
(Collaborative Decision Making) over the time period January -
June of 1998.
Download: Not yet publically available.
NEXTOR develops optimization models and decision support tools for
minimization of expected delays under uncertain weather conditions and fluctuating demand
and the fair allocation of resources among competing entities within the NAS.
Operations Research is the application and theoretical development of
scientific models that solve problems that arise in the context of the organization of, and resou
rce allocation within an operation, particularly when it is large or complex.
Collaborative Decision Making (CDM)
CDM is the most active and accomplished component of the
FAA's Free Flight Program. NEXTOR has worked closely with the CDM community to perform
long-term trend analyses, benefits assessments, and to develop appropriate metrics for
traffic flow management performance.
Air Traffic Flow Management
[add text here]
NEXTOR is heavily involved in data analysis for the support of efforts in
collaborative traffic flow management, aimed largely at the improvement of flight data quality.
These analyses include benefits and performance studies of large-scale traffic flow management
intiatives and the development and computation of new metrics for data quality and traffic flow
[plug Berkeley activities; form link]