DECISION MODELS FOR EMERGENCY
RESPONSE PLANNING
Larson, R., Metzger, M., & Cahn, M.
CREATE REPORT
Under FEMA Grant EMW-2004-GR-0112
September 28, 2004
Center for Risk and Economic Analysis of Terrorism Events
University of Southern California
Los Angeles, California
3710 McClintock Avenue, RTH 314 Los Angeles, CA 90089-2902 ~ (213) 740-5514 ~ www.usc.edu/create
Report #04-002
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Decision Models for Emergency Response Planning
Richard C. Larson, Massachusetts Institute of Technology
Engineering Systems Division and
Department of Civil and Environmental Engineering Room 1-170
Cambridge, MA 02139
and
Structured Decisions Corporation
1105 Washington Street
West Newton, MA 02465
This research was supported by the United States Department of Homeland Security through the Center for
Risk and Economic Analysis of Terrorism Events (CREATE), grant number EMW-2004-GR-0112.
However, any opinions, findings, and conclusions or recommendations in this document are those of the
authors and do not necessarily reflect views of the U.S. Department of Homeland Security.
A chapter submitted to
The McGraw-Hill Handbook of Homeland Security, David Kamien, editor.
September 28, 2004
Operations Research (O.R.), born in World War II (WWII), has for 65 years proved
invaluable as a decision-planning tool. Known as the science and technology of decision-
aiding, O.R. is an empirical science that uses the scientific method to assess the
consequences of alternative decisions, be they long-term strategic planning decisions or
shorter range tactical or operational decisions. Since a decision can be viewed as an
allocation of resources, Operations Research is the science of resource allocation. In
WWII O.R. helped guide the allocation of scarce resources against the enemy.
Successful applications ranged from finding optimal locations for new and expensive
radar installations in Great Britain (in order to detect incoming enemy aircraft and
missiles), to the invention of ‘optimal search theory,’ used to deploy aircraft and ships in
search of enemy submarines [32]. The search theory results were deemed so important
that the original papers by Bernard Koopman remained classified for 15 years. Today
O.R. is ideally suited for evaluating and guiding our operational strategies and actions
with regard to large scale emergency incidents, be they acts of terrorism, acts of Mother
Nature (e.g., earthquakes, floods, tornadoes, hurricanes) or industrial accidents.
Following WWII, Operations Research found widespread applications in civilian sectors,
both in private companies and in the nonmilitary government sectors. The collective
result has been savings of billions of dollars from costs of operation and significant
increases in the quality of services provided – in both the public and private sectors. The
majority of Fortune 500 companies have utilized O.R. inside to help them in their
decision making, long, medium and short term. The O.R. civilian sector includes the US
Postal Service, which for decades has used O.R. extensively for designing routes,
scheduling personnel and designing its national distribution network. It also includes the
City of New York, which as a result of 30 years of successful O.R. experience, created its
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own permanent O.R. group within the City’s Office of Management and Budget. And
the military has its own Military Operations Research Society, whose 3,000 members
must have a security clearance to attend its meetings.
O.R. is in many places where you least expect it. New England Patriots football coach
Bill Belichick uses O.R. in the execution of a football game. In a famous incident in
2003, with the ball on the Patriots’ side of the 50-yard line, on a fourth down and one-
yard-to-go situation, he went for first-down. His decision was viewed as contrary to what
90 percent of NFL football coaches would have done, but was supported by 30+ pages of
sophisticated “Bellman equation” O.R. analysis of a Stanford University professor
1
. The
decision proved correct, the first down was achieved, the team continued to a touchdown
and later in the season to another Super Bowl victory. O.R. is not just an academic
discipline, any more than electrical or mechanical engineering are just academic
disciplines. O.R. is an academic discipline that continues to have numerous substantial
beneficial impacts on organizations, large and small. While football and response to
terrorist attacks are very different operations, we cite the football example to show that
O.R. can be used to inform and transform decisions in the real world, with all its gritty
complexity. One needs that type of down-to-earth practical science to confront the many
challenges of emergency response planning and operation. As explained below, that is
why O.R. proved invaluable to New York City firefighters on September 11, 2001.
What are the methods of O.R.? The answer is: any aspect of the scientific method that
sheds light on the problem at hand. Usually but not always mathematics is involved.
Usually but not always a mathematical model of the system or problem being studied is
created, tested, refined and then implemented on a computer. Once computer-
implemented, the O.R. analyst runs the model under alternative assumptions, leading to
optimal or near-optimal system configuration or decision policies. But some very famous
O.R. studies have involved no mathematics at all, just clever application of ‘common
sense,’ often leading to new and insightful re-definitions of the problem.
Response to a major emergency incident requires careful planning and professional
execution of plans, when and if an emergency occurs. Decisions involve the movement
(‘deployment’) of people, equipment and supplies. They also include the development of
policies with regard to operation, once men, women and materiel are in place. This
setting is nearly perfect for the application of O.R. – to create better emergency response
plans and to design better operational policies once the rescue efforts are underway.
In this chapter we review briefly the major O.R. work done to date in emergency
response. Some of this work is quite recent and aimed directly at what we now call
Homeland Security issues. Most of it has evolved over the past 50 years, motivated by
other emergency applications, especially operation of first responders in municipalities –
police, fire and emergency medical. The good news is that we are now building from a
rich legacy of 50 years of research in emergency response. The bad news is that only
recently have we collectively refocused our energies towards catastrophic events
1
New York Times, David Lionhardt, “Incremental Analysis, with Two Yards to Go,” February 1, 2004.
Also see
http://espn.go.com/nfl/columns/garber_greg/1453717.html.
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associated with Homeland Security. But our 50-year’s of research and implementation
results provide us today with solid platforms for moving forward. Space limitations do
not allow us to provide a comprehensive literature review of the field of “O.R. and
emergency response.” So, we have selected the works that we feel are most important for
progressing with emergency response and Homeland Security. The new threats posed by
terrorists present myriad new problems for O.R. analysts. In some ways, today we stand
at a place analogous to the place that Drs. Philip M. Morse, George Kimball, Bernard
Koopman and other O.R. pioneers stood near the beginning of WWII. There are
numerous new O.R.-related problems to identify, to frame, to formulate and to solve.
Hopefully the end result will be the most rational deployment of our scarce national
resources, resulting in maximally many lives saved and injuries averted in the instance of
another terrorist attack. But since the methods we describe also apply to emergencies
created by Mother Nature and by human accident, let us hope that the vast majority of
incidents in which these methods are applied are from these latter two categories.
For purposes of this chapter, a major emergency is one in which local first responder
resources are overwhelmed. There simply are not enough resources to do the many jobs
at hand. To read a history of such an event, one that took place across the entire United
States, we suggest studying the ‘great influenza epidemic’ of 1918-1919, a pandemic that
took more American lives than all wars of the 20
th
Century [1]. Nurses, doctors and other
resources were simply too few to care for the sick and dying. But more critically, history
shows that lack of timely response to events as they unfolded and lack of disciplined
management strategies led to many unnecessary deaths. One of our goals here is to show
that careful and systematic approaches to the myriad operational problems associated
with emergency response can lead to policies and procedures that maximize the
effectiveness of the resources available. As a result, lives should be saved, and lifelong
debilitating injuries should be minimized.
1. First Responders: Police, Fire and Emergency Medical Services
Perhaps most relevant to emergency response planning is the 40 years of O.R. work
focused on urban and municipal first responders, i.e., police, fire and emergency medical.
This work started with the Science and Technology Task Force of the President’s
Commission on Law Enforcement and Administration of Justice in 1966 [6]. It led
directly to the national implementation of the three digit emergency number, ‘911,’ and it
sparked a generation of important O.R. emergency services research. When New York
City implemented its 911 system in 1970, managers there discovered how useful and
necessary queueing theory is in the scheduling of 911 call takers. Their original
scheduling of personnel, without the benefit of O.R. analysis, yielded intolerable 30+
minute telephone queue delays on weekend evenings, with the caller hearing only the
familiar and annoying ‘electronic ringing sound.’ An O.R. analysis quickly showed how
rescheduling current personnel – without additions -- brought the delays to within
acceptable limits. The recommendations were fully implemented within one month of
the study’s completion [21].
Queues occur when the available resources are not adequate to handle real time demand
for those resources. Queueing is a type of rationing of resources. Sometimes the
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rationing and delays are deliberate, as with some private sector call-in complaint centers.
In a major emergency, queues are endemic and must be managed aggressively by using
techniques such as prioritization and triaging. Triage classifies those who are injured into
various priority categories, and acts with urgency on the highest priority categories first,
trying to save as many lives as possible with the limited resources at hand. Without
triage, queues would grow without bound, and few would be treated in a timely manner.
Sometimes triaging requires very difficult deferral decisions, such as occurred on
December 7, 1941 at Pearl Harbor: triage nurses deciding against medical treatment
other than morphine for those who had been so severely injured that near-term death is a
certainty regardless of medical intervention. Such difficult decisions may be required to
save scarce medical expertise for treatment of those whose lives can be saved. Modeling
work on ‘cut-off priority queues” provides a methodology of setting priorities and
predicting system performance under alternative triaging schemes [35, 36]. In [33] we
show how this would work with data from the Hartford Connecticut Police Department.
The author of this chapter was a member of the Science and Technology Task Force of
the President’s Commission, and as a result of that work, wrote his Ph.D. thesis on urban
police patrol allocations. This culminated in a book, Urban Police Patrol Analysis, MIT
Press, 1972 [22]. This book offered a variety of O.R. models to examine police response
times, patrolling patterns, impact of new technologies (such as automatic vehicle
locations systems), personnel scheduling and more. This effort led to a major four-year
NSF-funded research program at the Massachusetts Institute of Technology, the “IRP
Project,” Innovative Resource Planning in Urban Public Safety Systems. That project led
to many graduate theses and computer-implemented models related to police and
emergency medical operations. It started ‘public safety’ O.R. careers of at least five
doctoral students [27].
The key model from the IRP project was the “Hypercube Queueing Model.” This
mathematical model depicts the detailed spatial operation of urban police departments
and emergency medical services [23, 25]. The model is an equation-based model that
uses various analysis tools from the technical field known as ‘stochastic processes.’ It is
a multi-server queueing model that reflects the unscheduled nature of 911 calls by
modeling them as a Poisson process. The service times of different servers (i.e., police
patrol cars or ambulances) are uncertain (i.e., probabilistic) and have different average
values, reflecting differing workloads and travel times in their areas of responsibility.
The Hypercube model has found application is police beat design, dispatcher car-picking
strategies, allocation of patrolling time, evaluating the response time reduction value of
automatic vehicle location systems, and more [28]. By combining the spatial and
temporal aspects of police and ambulance operations within one unified probabilistic
framework, the Hypercube model was the first to be able to predict the operational
consequences of alternative police deployments over space and time. It illustrated the
inadequacies of some deeply rooted beliefs that had become folklore in police
deployment [24]. In contrast to popular wisdom at the time, it predicted a large number
of inter-beat dispatches of police cars, a forecast later verified in the field [20]. It showed
that a police car may have an above-average workload even if its ‘own beat’ had virtually
no internally generated workload. The Hypercube Queueing model has been
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implemented in many cites, including New York City [30]; Boston, Massachusetts [7];
Hartford, Connecticut; Orlando, Florida; Dallas, Texas and Cambridge, Massachusetts.
The Orlando Police Department, for instance, in 1992 essentially redesigned the police
beat layout of the entire city, in order to create a new central city precinct [34]. Without
the model, the city’s police planners would have had no scientific basis for making such a
dramatic change in deployments. But with the model, they could be confident that the
new allocation scheme would satisfy all performance standards set by the department
[26].
Various vendors have commercialized the Hypercube model, and its full impact is
impossible to determine since not all implementations have been documented in the open
literature. From the perspective of Homeland Security, the analytical structure of the
Hypercube model offers promise in guiding response resources depleted in the event of a
major emergency. But the model needs to be generalized in order to include the impact
of second and third tier responders, from regional, state and federal agencies, and of
specialized responders such as HAZMAT and bio-terrorism units. It also needs a time-
dependent solution structure, fed with (potentially massive) data from the field. The
author, with research colleagues at Structured Decisions Corporation of West Newton,
Massachusetts, is building from the Hypercube model a new deployment model for
response to terrorist attacks and other large emergencies. The desired result is a model
that will guide event managers in the dispatch and routing of heterogeneous responders
on a regional interagency basis. The effort will also help local emergency planners to
identify and correct weaknesses in their response plans for major emergencies. This
effort is part of the CREATE project at the University of Southern California, funded by
the U. S. Department of Homeland Security.
In 1969 New York City commissioned the RAND Corporation of California to open the
New York City Rand Institute (NYCRI). The NYCRI assembled a team of analysts to
examine a wide variety of operational problems of the City [13, 17, 18]. Over the years,
their award-winning O.R. work on emergency services has stood the test of time. Some
of this work is still the best available today. An example is the NYCRI’s fire department
relocation model [19, 41]. When there is one large fire or a collection of smaller fires in
geographic proximity, the fire-fighting resources near the vicinity of the fire (or fires)
become depleted. Most fire departments try to re-balance protection by moving some of
the still-available fire companies from more distant firehouses to occupy temporarily
some of the firehouses left vacant by the busy companies. But this in turn creates new
relative vacancies at the more distant firehouses, which in turn require reassignment of
even more distant fire fighters into the newly vacated firehouses. This wave-like
cascading process, if not carefully managed, can create conditions in the city in which
certain neighborhoods are left uncovered, should a new fire occur there. The number of
ways to implement relocations is literally in the hundreds of billions, and no human can
contemplate the consequences of each option and pick the best. But computer-
implemented mathematical models such as the NYCRI relocation model are perfect for
the job at hand. The NYCRI was shut down in 1975 due to New York City’s severe
budget crisis. Remarkably, 30 years later, the NYCRI fire relocation model lives on in
the NYFD. In fact, it proved invaluable on September 11, 2001, in managing the
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relocations of NYC fire fighters on that infamous day. With the help of that model plus
implementation of a “Fallback 3” response strategy (meaning far less than usual number
of units initially dispatched to an incident), the NYFD managed to keep its average
response times to other more routine fire incidents to an average of 5.5 minutes, only
about one minute above the usual average
2
.
The NYCRI relocation methodology is most relevant in planning response to a terrorist
attack. The New York City 9/11 case is an ‘existence proof.” Any other terrorist attack is
also likely to overwhelm nearby first responders, thereby putting the entire city or region
at risk, if resources are not managed carefully. According to Dr. Peter Kolesar of
Columbia University, co-inventor of the NYCRI relocation model, in the event of
terrorist attack,
"Several core principles underlying the NYFD version would probably be appropriate.
First, solve the problem as it occurs rather than trying to plan in advance since you
probably cannot anticipate the dimensions of the attack and following crisis. Second, use
some politically acceptable mathematical measure to define when coverage is inadequate
and to evaluate alternative relocation options. Third, employ a computer driven
optimization algorithm to generate actual solutions. Fourth, allow the actual decision
makers to modify or override the algorithm's suggestions.”
3
University students are becoming increasingly interested in research on emergency
response. For example MIT doctoral student Michael Metzger has recently completed a
Masters thesis on deployment of rescue and recovery resources in response to an
earthquake [31]. He used data from the world’s most earthquake-prone country, Iran, to
illustrate the results of his O.R. analysis. Among other measures, his model predicts the
number of hospital admissions, and fatalities over the hours and days following the
earthquake. The results depend on the response strategy selected. Particularly important
are the strategies to select when more than one populated community is affected by
earthquake damage. The results are important, controversial and counter-intuitive. For
example, he shows that to save the maximum number of lives in all affected
communities, it may be necessary to dispatch ‘local’ responders from one of the affected
communities to travel to a more distant damaged community, in order to save lives there.
The result might be the saving of 100 or more lives in the more distant city ‘at a cost’ of
not saving some fewer number of lives in the ‘home city.’ Such sharing of resources
may be politically difficult and would require considerable citizen education prior to any
event in which it is implemented. Metzger’s methodology, which will appear soon in a
published article, demonstrates how one can model the temporal allocation of resources
following a catastrophic event, thereby finding ways to deploy personnel to save lives
and reduce occurrence of debilitating injuries.
We have given a very brief sampling of the many O.R. contributions to analysis of first
responders. For those who want additional detail, there are review papers available [13,
17, 18, 27], as well as summary books [29, 41]. And, there is prize-winning work in the
2
McKinsey Report, Increasing FDNY’s Preparedness.
http://www.ci.nyc.ny.us/html/fdny/html/mck_report/index.shtml
3
Peter Kolesar, private communications, August 10, 17, 2004.
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scheduling of police personnel [37]. We feel that the entire 40-year body of emergency
response O.R. work will prove invaluable in building the next generation of emergency
response models and methods, ones that are applicable to response to terrorist attacks and
to other major emergencies.
2. Hazardous Materials
The transportation of hazardous materials on trains, trucks and vessels exposes the public
to risks of environmental catastrophes, even in the absence of terrorist threats. The
possibility of a terrorist attack on hazardous materials in transit only increases the risk.
As one example, currently there is much debate about using deep caves at Yucca
Mountain in the Nevada desert for long-term storage of radioactive waste from nuclear
power plants. Should that or another location be selected and operations started, there
would be a massive transportation effort throughout the United States, hauling spent fuel
rods and other radioactive wastes to the selected location. Each city, town, village, or
farm that is passed by the train or other conveyance carrying the hazardous materials is at
risk of an accident and severe contamination.
Because of these threats, there have been O.R. studies focusing on the routing and
scheduling of hazardous materials, point to point on a transportation network such as the
national railway system, in ways that mitigate the risk and/or spread it equitably. The
work has shown that there are tradeoffs between efficiency and equity [2, 3, 5, 10, 14].
The lowest total system risk routes trains (or other conveyances) along the same path
each time. A more equitable policy employs various routes, with more people sharing the
risk, at a modest increase in total risk exposure. For the nuclear waste problem, the
selected routes are of course yet to be decided, but analyses point to the ways in which
efficiency and equity can be addressed in an integrated fashion.
Risk reducing routing of hazardous materials is an example of pre-event O.R. analysis.
By making improved decisions based on such analysis before a major emergency event
occurs, one can reduce the damage caused -- should the event occur -- and on occasion
even reduce the chance of the event ever happening. Of course, the ‘nonevent’ is the best
one for saving lives and property!
3. Bio-Terrorism
Carefully planned detection of and response to any bio-terrorism attack is crucial in terms
of saving lives. This new area of concern has only recently been the focus of O.R.
analyses. But the work has been widely reported and has had major national impact. The
developed models provide a consistent framework for considering operations following a
bio-attack. The work has changed our national policies with regard to immunizations and
medications following a bio-terrorist attack.
With regard to a possible anthrax attack, the co-authors Lawrence Wein and Edward
Kaplan state,
Two pounds of weapons-grade anthrax dropped on a large
American city could result in more than 100,000 deaths,
even if early cases were successfully diagnosed,
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antibiotics were distributed broadly and drug adherence was
high. The reason for the catastrophic death toll: Not
enough people would receive antibiotics quickly enough to
prevent symptoms from developing, and those who developed
symptoms would overwhelm the medical facilities.
Any plan to cope with this scenario must include (1)
immediate intervention, (2) rapid distribution of
antibiotics to everyone in the affected region, (3)
aggressive education to ensure adherence to the full course
of treatment and (4) creation of "surge capacity" to treat
the sudden influx of patients. [43]
Their conclusions, together with their colleague David Craft, were based on a highly
sophisticated set of mathematical models that included an airborne anthrax dispersion
model, an age-dependent dose-response model, a disease progression model, and a set of
spatially distributed two-stage queueing systems consisting of antibiotic distribution and
hospital care [42]. One of their most controversial recommendations is to have non-
professionals disperse antibiotics very soon after an attack and/or have those antibiotics
in the hands of citizens at all times – pre-positioned at the points of need in case of such
an attack [15]. Based on these recommendations, the US Postal Service has announced
that its mail carriers will help to distribute antibiotics if a large attack occurs in the
Washington D.C. area
4
.
The same three co-authors also used O.R. methods to study response to smallpox attack
[16]. The initial federal policy had been to isolate the symptomatic victims, trace and
vaccinate their contacts, quarantine others, and hope that the spread of disease could be
limited by these measures. The O.R. analysis, again based on a highly complex but
compelling set of models, indicated that the initially selected policy would result in many
deaths. Instead, the analysis suggested a different response: as soon as the attack is
recognized, undertake mass vaccination across the entire population. This
recommendation caused quite a stir nationally, in the press, among physicians and with
policy makers, but now has been adopted as official US policy.
O.R. is playing major roles in other aspects of medical response to major emergencies as
well. For instance, Linda Green has shown how usual efficiency measures defined in
terms of bed occupancy in hospitals cause large queueing delays for beds even in the
presence of routine demand; demands caused by major emergency events would
overwhelm such hospitals [11, 12]. Bravata et. al. extend the policy conclusions of the
anthrax and smallpox work described above to examine regionalized or local stockpiling
of drugs and response to bio-terrorism events [8, 44].
One can see here the need for additional O.R. research on optimal locations of drug and
equipment stockpiling. Traditional location theory seeks global optimal solutions that
minimize some measure of total system travel time or distance [29, Chapter 6]. Usually
one or a small number of carefully positioned facilities accomplish this travel time
4
United States Postal Service. U.S. Postal Service may deliver medicine in the event of a catastrophic
incident. News release no. 04-015, February 18, 2004.
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minimization goal. Within an environment of a major emergency, the traditional
formulation of the facility location problem may be highly inappropriate. Instead, one
has to consider that one or more of the stockpiled facilities may be destroyed by the
emergency event and/or travel paths leading from them may be damaged or inaccessible.
In such cases, one may want to position more than the usual number of facilities, each
containing fewer medications and supplies, in order to increase the probability of
survivability of the drug and supply distribution system. This version of the problem is
somewhat similar to the so-called the p-dispersion location problem, where p is the
number of facilities being dispersed. These issues are addressed in new papers by Gong
et. al. [9] and Berman et. al. [4].
Should a major bio-terrorism event occur at one identified location or limited region,
getting timely appropriate medical care to those exposed is critical for their survival. One
can imagine scenarios in which victims are first triaged, those identified as needing
immediate transport are taken to nearby hospitals or other medical facilities, initial
treatments are administered, and then many patients at the nearby hospital are moved out
to more distant locations. For if such outward movements are not done, the nearby
hospitals become queueing choke points in the system, with their own limited resources
totally overwhelmed. The cascading wave-like movement of patients out of nearby
facilities to more distant ones reminds one of the reverse of NYCRI’s fire relocation
model. Creating such hospital “surge capacity” (in the words of Kaplan and Wein)
certainly warrants further research.
Effective responses of healthcare systems are essential to the total societal response to
major events, be they terrorist attacks, acts of nature or man-caused accidents. The
number of components of these systems can be large, the relevant factors many, and their
interactions complex. Mathematical models are essential in order to understand all of the
complexities and tradeoffs, ultimately leading to more informed decisions and allocations
of scarce societal resources.
4. Private Sector Response
Emergency response is not limited to public sector agencies. In the event of a major
emergency such as a terrorist attack, it is important that private firms whose operations
have been interrupted by the emergency resume normal operation as soon as possible.
Operations Research can play a role in that normalization process.
There are few companies whose operations are more complex than airlines. With
thousands of flights scheduled each day, the efficient matching of planes and crews to
schedules and airports is an intricate, carefully choreographed optimization problem.
When unplanned events occur, myriad decisions must be made. “Usual events” in the
airline industry are “Chicago O’Hare closed due to snow” or “Miami closed due to a
hurricane.” These Mother-Nature-caused events are difficult enough to handle, as
hundreds of flights and thousands of passengers may be affected. But imagine what
happens when all planes are unexpectedly grounded. And, on September 11, 2001 all
civilian airlines were grounded. Planes that had been in the air at the time of the 9/11
emergencies were directed to nearby airports for landing. At the end of the day, the
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airlines and their passengers found themselves literally all over the country and even
outside of the country, often at locations far from the intended destinations. The state of
each airline was very far from what had been carefully planned. Yet, as described in
award-winning work [38, 39, 40], O.R. optimization resulted in Continental Airlines
having the "best" recovery of any major airline in terms of percentage of
delays/cancellations during the restart phase that followed the nationwide grounding of
commercial aircraft. The computer-implemented O.R. methodology determined the
least-cost sequence of decisions to get the airline up and flying again, consistent with the
thousands of constraints dealing with matching crews to planes to which they are
qualified, getting each plane back on schedule, adhering to maintenance schedules,
obeying FAA rules with regard to maximum allowable flying times of crews, etc. Since
that time, many other airlines have adopted this proprietary O.R. methodology to assure
their swift recovery from major events to resuming regular operations.
The events of 9/11 affected many industries in addition to airlines. For instance the
mantra of ‘just in time’ supply chain management was tossed out the window on 9/11 due
to a lack of redundancy and slack in ‘just-in-time” systems. Hundreds of trucks were
lined up on the Canadian border on September 12, 2001, awaiting customs and
immigration clearance into the USA. As a result of these delays, factories in the US
began experiencing parts and supplies shortages. This has led to a new type of supply
chain analysis, one that requires robustness in case of emergencies, one that trades of
just-in-time efficiencies with redundancies needed to maintain normal operations in case
of interruption from a major event. This is another area for the analytical, model-based
approaches.
5. Implementation
Many of the models and methods discussed herein are being used on a daily basis by first
responder emergency services throughout the United States. As discussed, the NYCRI
‘fire department relocation model’ was used extensively and successfully by the New
York Fire Department on that fateful day, September 11, 2001. Private firms have
implemented and often extended the methodologies discussed here into real-time
command and control systems, such as computer-aided dispatch systems and regional
emergency management systems. The end user in such circumstances probably does not
even know that “O.R. is inside” the computer programs she is using. This is as it should
be, just as the user of an Internet search engine such as Google does not care about the
mathematical or logical details of Google’s search engine, only in the usefulness of the
results. The final proof of the value of O.R. is in the quality of decisions made from those
who benefit from its use.
With computer computation and storage being exceedingly inexpensive these days,
relative to the past, we are seeing more and more databases being assembled that will
assist the O.R. planner in preparation for emergency response. One of these is New York
City’s Citywide Assets and Logistics Management System
5
(CALMS). CALMS, set up
for disaster response, is the only New York City system that cuts across jurisdictional
5
http://www.nyc.gov/html/oem/html/response/calms.html
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lines and retains knowledge of the whereabouts of supplies, equipment and personnel
from many different agencies. It is organized according to six asset types: fleet,
equipment and supplies, facilities, contracts, personnel and donated goods. CALMS
automatically gets periodic uploads, to refresh its databases. And, its spatially oriented
data can be displayed on maps of the appropriate parts of the City via a Geographic
Information System (GIS) mapping tool. Eventually we see systems such as CALMS
instilled with intelligent O.R.-based models and algorithms that would recommend the
best movements of men, women and materiel in response to an emergency event. A
similar inclusion of O.R. may be expected in now widely-implemented Emergency
Incident Management Systems, computer-based systems to coordinate the management of
resources in response to an emergency and one in which there is now an effort to
standardize nationally
6
.
The need for O.R. talent in the domain of Homeland Security is apparent. The U.S.
Department of Homeland Security has job openings for professionals with O.R. training.
The City of New York has hired such people. Even the taxicab system of New York City
has sought such professionals, as needed talent to interact with consultants who are
examining the consequences of using GPS vehicle positioning technology on New York
City taxicabs. O.R. professionals often have undergraduate degrees in electrical
engineering, computer science or mechanical engineering, so they can integrate technical
engineering knowledge into the systems framework of Operations Research.
A growing new professional career is that of emergency services manager. Emergency
services managers may also be called emergency program managers or directors,
operations center chiefs and risk management experts. They are professionals who
coordinate equipment, emergency workers and volunteers who move into action
following any disaster. They make sure that government, volunteer and medical
personnel work together cohesively and effectively during an emergency. Knowledge of
operations research is increasingly a job requirement.
7
Universities such as Virginia’s
University of Richmond offer certificates and degrees in Emergency Services
Management.
The public, in weather forecasts, has been exposed for many years to the types of
probabilistic analyses we have discussed. We are all accustomed to hearing that, “…the
probability of rain tomorrow is 0.4.” Quantified uncertainty has become a part of our
daily lives. More critical to Homeland Security, the public is also aware of probabilities
associated with hurricanes, particularly where and when they will achieve landfall.
Public preparedness for and response to hurricanes are important components of
Homeland Security, as a Category 3, 4 or 5 hurricane making landfall of the United
States certainly conforms to our definition of major emergency. The types of analyses
we have been discussing are used today to create the ‘probability risk profile’ of
approaching hurricanes. They are also used to make decisions on evacuations. Here
additional O.R. analyses may be valuable on the detailed planning of evacuations, to
minimize false alarms and the public apathy that may result and also to minimize the
6
See http://www.dhs.gov/dhspublic/display?content=3259.
7
http://www3.ccps.virginia.edu/career_prospects/briefs/E-J/EmergencyManage.html
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chance that evacuees could end up in congested roadways subject to local flooding.
There is still much to do.
6. Summary and Conclusions
Operations Research, the science and technology of decision aiding, helped immensely in
WWII. Today we face a different set of threats, a new type of warfare labeled
asymmetrical. This type of threat creates the possibility for large-scale devastation
similar to that caused by Mother Nature and by man-made accidents. Planning
appropriate societal response to such large-scale emergencies, should they occur, can
save many lives and reduce extent of injuries. Hardware technology alone, without
careful systems planning is not enough. And there is not enough money in the public
coffers to think that simply ‘throwing money at the problem’ will solve it. Operations
research offers a scientifically valid, integrated framework for considering all aspects of
the problem and for assessing the consequences and tradeoffs associated with alternative
decisions. We expect to see many more new results from Operations Research in the
years ahead, as the nation comes to grip with the new threats from terrorists and the old
threats from Mother Nature and industrial accidents.
Acknowledgement. This research was supported by the United States Department of Homeland Security
through the Center for Risk and Economic Analysis of Terrorism Events (CREATE). The work was
conducted through a subcontract from CREATE at the University of Southern California to Structured
Decisions Corporation, West Newton, Massachusetts. For helpful comments on an earlier draft, the author
thanks Andrea Allocca (New York Fire Department [NYFD]), Linda Green, Peter Kolesar, Lawrence
Wein, Gang Yu and the editor of this book, David Kamien.
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