Welcome to the Fulbright Senior Specialist page of Anna Nagurney, the John F. Smith Memorial Professor at the University of Massachusetts at Amherst. In March 2008, she was a Fulbright Senior Specialist in Business Administration at the Department of Mathematics and Computer Sciences at the University of Catania, Italy. Below you will find information regarding various activities associated with her award.  








Acknowledgments: Professor Anna Nagurney acknowledges the support provided by her 2008 Fulbright Senior Specialist Award in Business Administration to the University of Catania. She also thanks Professors Patrizia Daniele and Antonino Maugeri of the Department of Mathematics and Computer Sciences at the University of Catania, Italy, for their wonderful assistance and support, which made this Fulbright Award possible.


Last
Update: March 29, 2008


Fulbright Senior Specialist Lecture  Monday, March 10, 2008 Vulnerability
Analysis of Complex Networks from Transportation Networks to the Anna Nagurney Abstract: Networks provide the foundations for communication, transportation and logistics, energy provision, as well as financing. The study of networks spans many disciplines due to their wide application and importance (see, e.g., Beckmann, McGuire, and Winsten (1956), Sheffi (1985), Ahuja, Magnanti, and Orlin (1993), Nagurney (1999), Patriksson (1994), Ran and Boyce (1996), Watts and Strogatz (1998), Barabasi and Albert (1999), Latora and Marchiori (2001), Newman (2003), Roughgarden (2005), Daniele (2006), and the references therein). The subject has garnered renewed interest, since a plethora of catastrophic events such as 9/11, the North American electric power blackout in 2003, followed by blackouts in Italy and Switzerland, Hurricane Katrina in 2005, the Minneapolis bridge collapse in 2007, as well as the Mediterranean submarine cable disruption in 2008, and the snowstorm precipitated transportation and electric power failures in China in the winter of 2008, among others, have drawn great attention to the study of network vulnerability. The recent theories of scalefree and smallworld networks in complex network research (cf. Watts and Strogatz (1998) and Barabasi and Albert (1999)) have significantly enhanced our understanding of the behavior as well as the vulnerability of many important realworld networks (see also, e.g., Barabasi, Albert, and Jeong (2000), Amaral et al. (2000), Chassin and Posse (2005), and Holmgren (2007)). However, the majority of network vulnerability studies focus solely on the topological characteristics such as the connectivity or the average shortest path length of the network. Although the topological structure of a network provides crucial information regarding network vulnerability, the flow on a network is also an important indicator, as are the flowinduced costs and the behavior of the users both prior and post any disruptions. As pointed out by Barabasi (2003, pp. 225), "To achieve that [understanding of complexity] we must move beyond structure and topology and start focusing on the dynamics that take place along the links. Networks are only the skeletons of complexity, the highways for various processes that make our world hum." Latora and Marchiori (2001, 2002, 2004) proposed a network efficiency measure that is shown to have advantages over several existing network measures. The authors then used the measure to study the (MBTA) Boston subway transportation network and the Internet. Their measure considers geodesic information. In this
presentation we will describe our recent research on the development
and application of a new network efficiency/performance measure that
incorporates such important network factors as flows, costs, and behaviors
in order to assess the importance of network components. It will be
shown that the new network measure has advantages over several existing
network measures. Furthermore, the measure will be able to handle both
fixed and elastic demands as well as static and dynamic networks, with
the latter of particular In addition, instead of looking at the situation where a network component is completely disrupted, network robustness, another important aspect of the vulnerability of the network, investigates cases in which network resources, such as link capacity, are reduced in stressful environments. As defined in IEEE (1990), the robustness of a system is "the degree to which a system or component can function correctly in the presence of invalid inputs or stressful environmental conditions." This topic is especially important now since it has been reported that the once worldenvied U.S. infrastructures are experiencing tremendous aging and deterioration, which exposes additional vulnerability to disasters. Moreover, due to the constant breakdowns of the U.S. transportation networks and the increasing number of vehicles, American commuters now spend 3.5 billion hours a year stuck in traffic, which translates to a cost of $63.2 billion a year to the economy (ASCE (2005)). At the same time, a recent report from the Federal Highway Administration (2006) states that the U.S. is experiencing a freight capacity crisis that threatens the strength and productivity of the U.S. economy. Hence, the construction of suitable transportation network robustness measures is of both theoretical and practical importance. In this presentations, we will also present new results on transportation network robustness based on the new network efficiency/performance measure in order to investigate the network functionality when the links are partially degraded. Transportation network equilibrium models will serve as our network equilibrium paradigm for complex networks since a variety of networks, including the Internet, financial networks, supply chain networks, as well as electric power networks can be reformulated and solved as transportation network problems (cf. Nagurney, Parkes, and Daniele (2007), Nagurney (2006), Wu et al. (2006), and Liu and Nagurney (2007)). Hence, any insights gained from transportation networks are expected to greatly help in the understanding of the vulnerability and robustness of other complex networks. Some of the research that this presentation is based on has been reported in a series of papers by Nagurney and Qiang published in the operations research/optimization, physics, transportation/operations management, and economics literatures.


Fulbright
Senior Specialist Workshop Lecture  Wednesday, March
12, 2008 in Mergers and Acquisitions Anna Nagurney and Trisha Woolley Abstract: In this paper, we focus on synergy rather than vulnerability, and we quantify and assess, from a supply chain network perspective, the environmental effects resulting when a merger of two firms or an acquisition of one firm by another occurs. We develop a multicriteria decisionmaking supply chain network framework that captures the economic activities of manufacturing, storage, and distribution pre and post the merger. The variational inequalitybased models yield the system optima associated with the minimization of total costs and the total emissions under firmspecific weights. We propose a synergy measure that captures the total generalized cost. We then apply the new mathematical framework to quantify the synergy obtained for specific numerical examples. This work generalizes the recent systemoptimization models for supply chain network integration and associated synergies of Nagurney (2007), forthcoming in Transportation Research E, to the environmental and multicriteria dimensions.


Fulbright Senior Specialist Lecture Thursday, March 13, 2008 Operations Research and the Captivating Study of Networks and Complex Decisionmaking Anna Nagurney Abstract: In this talk, I will overview some of the major early and recent contributions to the formal mathematical study of networks and associated decisionmaking, from the perspective of an operations researcher. I will highlight novel mathematical tools, such as nonlinear optimization, game theory, variational inequalities, and projected dynamical systems, that have been utilized for the rigorous formulation of numerous networkbased problems, and their effective solution. Some of the operationsresearch applications that I will discuss are: congested transportation networks and the Internet, including the Braess paradox (with fixed and timevarying demands), supply chains, financial and social networks, and energy/environmental networks. The mathematical networkbased discoveries continue to impact numerous disciplines, including: engineering, computer science, physics, economics, and biology, where the formalism of networks brings new, refreshing, and unifying insights.


Presentations
at the Workshop
Complex Networks  Equilibrium and Vulnerability Analysis with Applications Anna Nagurney,
Isenberg School of Management, University of Massachusetts at Amherst, Vulnerability
Analysis of Complex Networks from Transportation Networks to the Patrizia Daniele, Department of Mathematics and Computer Sciences, University of Catania, Variational Inequalities and Applications to Complex Dynamic Multilevel Models Laura Scrimali, Department of Mathematics and Computer Sciences, University of Catania, Quasivariational Inequalities and Applications to Complex Networks Fabio Raciti, Department of Mathematics and Computer Sciences, University of Catania, Random Variational Inequalities and Applications to Network Equilibrium Problems Salvo Scellato, Scuola Superiore, University of Catania, Epcast: Controlled Dissemination in Humanbased Wireless Networks by Means of Epidemic Spreading Models Antonino Maugeri and Fabio Raciti, Department of Mathematics and Computer Sciences, University of Catania, On Existence Theorems for Variational Inequalities Stephane Pia, D.I.M.E.T., Faculty of Engineering, University of Reggio Calabria, Recent Results in Hilbert Spaces for PDS and VI when Duality Appears Annamaria Barbagallo and Stephane Pia, Department of Mathematics and Computer Sciences, University of Catania, and D.I.M.E.T., Faculty of Engineering, University of Reggio Calabria, Weighted Variational Inequalities in Nonpivot Hilbert Spaces: Existence and Regularity Results and Applications Sofia Giuffrè, Giovanna Idone, and Stephane Pia, D.I.M.E.T., Faculty of Engineering, University of Reggio Calabria, Some Classes of Projected Dynamical Spaces in Banach Spaces and Equivalence Results Alessio Cardillo, I.N.F.N., University of Catania, Structural Properties of Urban Street Patterns and the Multiple Centrality Assessment Anna Nagurney and Trisha Woolley, Isenberg School of Management, University
of Giuseppe Mangioni and Vincenzo Nicosia, D.I.I.T., Faculty of Engineering, University of Catania, Extension of Modularity for Overlapping Communities Detection in Complex Directed Graphs Maria Bernadette Donato, Department of Mathematics, University of Messina, A Competitive Equilibrium for a Pure Exchange Walrasian Economy: A Quasivariational Approach Monica Milasi, Department
of Mathematics, University of Messina, Existence
of
