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List
of Papers for 2005:
(in reverse chronological order)
ESD-WP-2005-10-Degree
Correlations and Motifs in Technological Networks
Recent
network research has sought to characterize complex systems with
a number of statistical metrics, such as power law exponent (if
any), clustering coefficient, community behavior, and degree correlation.
A larger goal of such research is to obtain insight into the systems’
functions by means of these and similar analyses. In this paper
we examine network models of mechanical assemblies. Such systems
are well understood functionally. We show that they have both
rich and varied community structure as well as negative degree
correlations (disassortative mixing), and show that this can be
explained by additional powerful constraints that arise from identifiable
first principles. In addition, we note that their main “motif”
is closed loops (as it is for electric and electronic circuits),
a pattern that conventional network analysis does not detect but
which is used by software designed to aid in the design of such
systems. The implication is that functional understanding of complex
systems requires considerable domain knowledge beyond what typical
network analysis tools employ.
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ESD-WP-2005-09-Analysis
of the Malaysian Toll Road Public-Private Partnership Program
and Recommendations for Policy Improvements
Malaysia
has relied on toll road public-private partnerships (PPPs) for
over twenty years to provide important highway infrastructure.
The program has been active with nearly 1800 kilometers either
constructed or concessions agreed to. The public has been less
supportive of the program due to low transparency and little public
involvement. Public protests are common, which may lead to long-term
program instability. The CLIOS Process, developed at MIT, is applied
to Malaysia’s toll road PPP program to develop new policies
that can better meet these public concerns while maintaining the
financial viability of the sector. With increases in transparency
and public involvement, the political risks of the program should
be reduced and long-term stability for the government and concessionaires
improved. We argue that the focus should be at the regional transportation
planning level where toll road PPPs can be compared with alternatives
for meeting transportation needs rather than at the national level
where Malaysian toll road PPPs are currently handled.
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ESD-WP-2005-08-Using
Design Structure Matrices to Improve Decentralized Urban Transportation
Systems
Management
of large, complex, urban transportation systems involves numerous
stakeholders due to the decentralized ownership and operation
of distinct pieces of the physical network and services. In order
to deliver better service to users, many urban regions are adopting
technological and operational solutions, both of which necessitate
interaction among the decentralized organizations. This research
applies systems engineering analysis techniques—the design
structure matrix (DSM) and clustering—in order to improve
the efficiency and effectiveness of organizational interactions
between agencies as they deploy Intelligent Transportation Systems
(ITS) and attempt to integrate their operations. Specifically,
we examine the application of clustering to the institutional
structure set forth by the Regional ITS Architecture for metropolitan
Seattle.
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ESD-WP-2005-07-Characterizing
Three Engineering Systems Methods for Supporting Regional Strategic
Transportation Planning Applied to Freight Systems
by
Sgouris P. Sgouridis, Joseph
M. Sussman, and Christopher Glazner
A systems
perspective for regional strategic transportation planning (RSTP)
for freight movements involves an understanding of Supply Chain
Management (SCM). This paper starts from the premise that the
public sector needs to enhance economic development in the form
of providing and ensuring the operation of sufficient network
capacity for freight needs but at the same time secure the region’s
long term environmental and societal well being. The need for
long-term integrated transportation planning that is sensitive
to supply chain needs and environmental nuances can be supported
by the use of engineering systems methodologies. Here we demonstrate
the use and potential of three such methods: Design Structure
Matrix (DSM), System Architecture (SA) and System Dynamics in
support of a transportation planning process that integrates SCM
considerations into RSTP.
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ESD-WP-2005-06-Multi-Airport
Systems in the Era of No-Frills Airlines
The development
of no-frills airlines is promoting a remarkable expansion in the
number of secondary airports in major metropolitan areas. These
new carriers are creating a significant alternative to the traditional
full-service carriers. In effect, they are establishing a parallel
market and corresponding network of airports. This conclusion
results from the analysis of a worldwide database on major metropolitan
airports.
This effect
supplements the "number of originating passengers",
that has been the traditional significant factor that promotes
the establishment of viable multi-airport systems. This factor
maintains its importance, but no longer is as decisive as it has
been.
Airlines
and airport policies further reinforce the independent network
of secondary airports. Nofrills airlines that sell only through
the web to customers effectively cause their services at secondary
airports to disappear from the airline reservation systems. Airports
that choose not to provide low-cost service to no-frills airlines
likewise strengthen the role of the secondary airports. Such strategies,
most visible in Europe, have led to a remarkable proliferation
of secondary airports in unexpected areas.
This trend
implies a traffic shift away from the expensive, congested airports
toward the no-frills, inexpensive and uncongested airports in
major metropolitan areas. If the current major airlines do shrink
substantially, as could happen, this would greatly change the
pattern of airport traffic in major metropolitan areas.
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ESD-WP-2005-05-Building
Real Options into Physical Systems with Stochastic Mixed-Integer
Programming
The problem
of building real options into physical systems has three features:
- real
options are not as easily defined as financial options;
- path-dependency
and interdependencies among projects mean that the standard
tools of options analysis tools are insufficient; and
- the
focus is on identifying the best way to build flexibility into
the design – not to
value individual options.
This paper
suggests a framework for exploring real options in physical systems
that especially addresses these two difficulties. This framework
has two stages: options identification and options analysis. The
options identification stage consists of screening and simulation
models that focus attention on a small subset of the possible
combination of projects. The options analysis stage uses stochastic
mixed-integer programming to manage the path-dependency and interdependency
features. This stochastic formulation enables the analyst to include
more technical details and develop explicit plans for the execution
of projects according to the contingencies that arise. The paper
illustrates the approach with a case study of a water resources
planning problem, but the framework is generally applicable to
a variety of large-scale physical systems.
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ESD-WP-2005-04-Management
of Technology Investment Risk with Real Options-Based Design:
A case study of an innovative building technology
Implementation
of innovative technologies is hindered by the perceived risks
of technical failure or increased first cost. However, by designing
a system to include real options within its architecture and by
recognizing the value in operational flexibility, the project’s
value is structured to avoid downside risks yet benefit from upside
opportunities. A real options based methodology for innovative
engineering system design consists of identifying relevant uncertainties,
designing options “in” the system, and modeling the
performance of the options-based design subject to the uncertainties.
The results guide decision makers on how much to spend on the
design and construction of a flexible system. A case study of
the market value of an innovative naturally ventilated building
with embedded option to install mechanical cooling in the future
demonstrates how the option “in” the system protects
the asset from downside outcomes in market value yet allows it
to benefit from upside opportunities.
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ESD-WP-2005-03-Value-at-RiskAnalysis
for Real Options in Complex Engineered Systems
This paper
presents a simple but powerful Real Options Valuation methodology
suitable for valuing flexibility in complex engineered systems.
It is based on value-at-risk analysis and relies on a standard
discounted cash flow approach. A case study on the architecting
of flexible satellite fleets is presented. The architecting framework
integrates spacecraft engineering design with economic analysis
for the purpose of maximizing the financial value of a fleet to
the operator under uncertain, evolving market conditions. The
investigation considers the forecasted demand evolution for a
satellite service in two distant geographical markets simultaneously
and provides flexible fleet architectures that significantly improve
various aspects of the value-at-risk distributions compared to
those of a traditional, rigid fleet architecture. It is shown
that the flexible architectures are able to capture more revenue,
mitigate more risk and/or reduce overall required investment.
The suggested Real Options “in” the system, rather
than “on” the system, approach allows engineers, strategists,
or decision makers in engineering establishments to embed flexibility
in the design of complex systems for the purpose of maximizing
their total lifetime value.
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ESD-WP-2005-02-Semantic
Information Integration in the Large: Adaptability, Extensibility,
and Scalability of the Context Mediation Approach
by
Thomas Gannon, Stuart
Madnick, Allen Moulton, Michael Siegel, Marwan Sabbouh, Hongwei
Zhu
There
is pressing need for effectively integrating information from
an ever increasing number of available sources both on the web
and in other existing systems. A key difficulty of achieving this
goal comes from the pervasive heterogeneities in all levels of
information systems. Existing and emerging technologies, such
as the Web, ODBC, XML, and Web Services, provide essential capabilities
in resolving heterogeneities in the hardware and software platforms,
but they do not address the semantic heterogeneity of the data
itself. A robust solution to this problem needs to be adaptable,
extensible, and scalable.
In
this paper, we identify the deficiencies of traditional approaches
that address this problem using hand-coded programs or require
complete data standardization. The COntext INterchange (COIN)
approach overcomes these deficiencies by declaratively representing
data semantics and using a mediator to create the necessary conversion
programs using a small number of conversion rules. The capabilities
of COIN is demonstrated using an intelligence information integration
example consisting of 150 data sources, where COIN can automatically
generate the over 22,000 conversion programs needed to enable
semantic integration using only six parametizable conversion rules.
This paper makes a unique contribution by providing a systematic
evaluation of COIN and other commonly practiced approaches.
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ESD-WP-2005-01-Research
Initiative to Understand & Model State Stability: Exploiting
System Dynamics
by
Nazli Choucri, Stuart
E. Madnick, Michael D. Siegel
In its
Preface, The 9/11 Commission Report states: “We learned
that the institutions charted with protecting …national
security did not understand how grave this threat can be, and
did not adjust their policies, plans, and practices to deter or
defeat it” (2004: xvi). Given current realities and uncertainties
“better preparedness” can be achieved by identifying,
controlling and managing the elusive linkages and situational
factors that impact state stability and fuel state decay and destruction
– and hence create new threats to the nation’s security.
We propose
to focus on the use of system dynamics modeling techniques to
help understand, measure and model the complex dynamics shaping
state stability, initially for two regions. We will specifically
consider the impacts of unanticipated disruptions, such as a tsunami
and its aftermath, on the dynamics of the two regions. For each
region, we will deliver a detailed country model, including 3-5
futures predictions in the 6-12 month range along with an analysis
of conditions and casual links between predicted futures plus
corresponding mitigated options.
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